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28251dfa64
hush/shell/ash.c
Denys Vlasenko 28251dfa64 Make it possible to select "sh" and "bash" aliases without selecting ash or hush 
The same can be done for msh, but we are probably better off just deleting it
in a next versio or two.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-01-01 13:01:04 +01:00

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/* vi: set sw=4 ts=4: */
/*
* ash shell port for busybox
*
* This code is derived from software contributed to Berkeley by
* Kenneth Almquist.
*
* Original BSD copyright notice is retained at the end of this file.
*
* Copyright (c) 1989, 1991, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* Copyright (c) 1997-2005 Herbert Xu <herbert@gondor.apana.org.au>
* was re-ported from NetBSD and debianized.
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
//config:config ASH
//config: bool "ash"
//config: default y
//config: depends on !NOMMU
//config: help
//config: Tha 'ash' shell adds about 60k in the default configuration and is
//config: the most complete and most pedantically correct shell included with
//config: busybox. This shell is actually a derivative of the Debian 'dash'
//config: shell (by Herbert Xu), which was created by porting the 'ash' shell
//config: (written by Kenneth Almquist) from NetBSD.
//config:
//config:config ASH_OPTIMIZE_FOR_SIZE
//config: bool "Optimize for size instead of speed"
//config: default y
//config: depends on ASH || SH_IS_ASH || BASH_IS_ASH
//config: help
//config: Compile ash for reduced size at the price of speed.
//config:
//config:config ASH_INTERNAL_GLOB
//config: bool "Use internal glob() implementation"
//config: default y # Y is bigger, but because of uclibc glob() bug, let Y be default for now
//config: depends on ASH || SH_IS_ASH || BASH_IS_ASH
//config: help
//config: Do not use glob() function from libc, use internal implementation.
//config: Use this if you are getting "glob.h: No such file or directory"
//config: or similar build errors.
//config:
//config:config ASH_RANDOM_SUPPORT
//config: bool "Pseudorandom generator and $RANDOM variable"
//config: default y
//config: depends on ASH || SH_IS_ASH || BASH_IS_ASH
//config: help
//config: Enable pseudorandom generator and dynamic variable "$RANDOM".
//config: Each read of "$RANDOM" will generate a new pseudorandom value.
//config: You can reset the generator by using a specified start value.
//config: After "unset RANDOM" the generator will switch off and this
//config: variable will no longer have special treatment.
//config:
//config:config ASH_EXPAND_PRMT
//config: bool "Expand prompt string"
//config: default y
//config: depends on ASH || SH_IS_ASH || BASH_IS_ASH
//config: help
//config: "PS#" may contain volatile content, such as backquote commands.
//config: This option recreates the prompt string from the environment
//config: variable each time it is displayed.
//config:
//config:config ASH_BASH_COMPAT
//config: bool "bash-compatible extensions"
//config: default y
//config: depends on ASH || SH_IS_ASH || BASH_IS_ASH
//config: help
//config: Enable bash-compatible extensions.
//config:
//config:config ASH_IDLE_TIMEOUT
//config: bool "Idle timeout variable"
//config: default n
//config: depends on ASH || SH_IS_ASH || BASH_IS_ASH
//config: help
//config: Enables bash-like auto-logout after $TMOUT seconds of idle time.
//config:
//config:config ASH_JOB_CONTROL
//config: bool "Job control"
//config: default y
//config: depends on ASH || SH_IS_ASH || BASH_IS_ASH
//config: help
//config: Enable job control in the ash shell.
//config:
//config:config ASH_ALIAS
//config: bool "Alias support"
//config: default y
//config: depends on ASH || SH_IS_ASH || BASH_IS_ASH
//config: help
//config: Enable alias support in the ash shell.
//config:
//config:config ASH_GETOPTS
//config: bool "Builtin getopt to parse positional parameters"
//config: default y
//config: depends on ASH || SH_IS_ASH || BASH_IS_ASH
//config: help
//config: Enable support for getopts builtin in ash.
//config:
//config:config ASH_BUILTIN_ECHO
//config: bool "Builtin version of 'echo'"
//config: default y
//config: depends on ASH || SH_IS_ASH || BASH_IS_ASH
//config: help
//config: Enable support for echo builtin in ash.
//config:
//config:config ASH_BUILTIN_PRINTF
//config: bool "Builtin version of 'printf'"
//config: default y
//config: depends on ASH || SH_IS_ASH || BASH_IS_ASH
//config: help
//config: Enable support for printf builtin in ash.
//config:
//config:config ASH_BUILTIN_TEST
//config: bool "Builtin version of 'test'"
//config: default y
//config: depends on ASH || SH_IS_ASH || BASH_IS_ASH
//config: help
//config: Enable support for test builtin in ash.
//config:
//config:config ASH_HELP
//config: bool "help builtin"
//config: default y
//config: depends on ASH || SH_IS_ASH || BASH_IS_ASH
//config: help
//config: Enable help builtin in ash.
//config:
//config:config ASH_CMDCMD
//config: bool "'command' command to override shell builtins"
//config: default y
//config: depends on ASH || SH_IS_ASH || BASH_IS_ASH
//config: help
//config: Enable support for the ash 'command' builtin, which allows
//config: you to run the specified command with the specified arguments,
//config: even when there is an ash builtin command with the same name.
//config:
//config:config ASH_MAIL
//config: bool "Check for new mail on interactive shells"
//config: default y
//config: depends on ASH || SH_IS_ASH || BASH_IS_ASH
//config: help
//config: Enable "check for new mail" function in the ash shell.
//applet:IF_ASH(APPLET(ash, BB_DIR_BIN, BB_SUID_DROP))
//applet:IF_SH_IS_ASH(APPLET_ODDNAME(sh, ash, BB_DIR_BIN, BB_SUID_DROP, ash))
//applet:IF_BASH_IS_ASH(APPLET_ODDNAME(bash, ash, BB_DIR_BIN, BB_SUID_DROP, ash))
//kbuild:lib-$(CONFIG_ASH) += ash.o ash_ptr_hack.o shell_common.o
//kbuild:lib-$(CONFIG_SH_IS_ASH) += ash.o ash_ptr_hack.o shell_common.o
//kbuild:lib-$(CONFIG_BASH_IS_ASH) += ash.o ash_ptr_hack.o shell_common.o
//kbuild:lib-$(CONFIG_ASH_RANDOM_SUPPORT) += random.o
/*
* The following should be set to reflect the type of system you have:
* JOBS -> 1 if you have Berkeley job control, 0 otherwise.
* define SYSV if you are running under System V.
* define DEBUG=1 to compile in debugging ('set -o debug' to turn on)
* define DEBUG=2 to compile in and turn on debugging.
*
* When debugging is on (DEBUG is 1 and "set -o debug" was executed),
* debugging info will be written to ./trace and a quit signal
* will generate a core dump.
*/
#define DEBUG 0
/* Tweak debug output verbosity here */
#define DEBUG_TIME 0
#define DEBUG_PID 1
#define DEBUG_SIG 1
#define DEBUG_INTONOFF 0
#define PROFILE 0
#define JOBS ENABLE_ASH_JOB_CONTROL
#include <setjmp.h>
#include <fnmatch.h>
#include <sys/times.h>
#include <sys/utsname.h> /* for setting $HOSTNAME */
#include "busybox.h" /* for applet_names */
#if defined(__ANDROID_API__) && __ANDROID_API__ <= 24
/* Bionic at least up to version 24 has no glob() */
# undef ENABLE_ASH_INTERNAL_GLOB
# define ENABLE_ASH_INTERNAL_GLOB 1
#endif
#if !ENABLE_ASH_INTERNAL_GLOB && defined(__UCLIBC__)
# error uClibc glob() is buggy, use ASH_INTERNAL_GLOB.
# error The bug is: for "$PWD"/<pattern> ash will escape e.g. dashes in "$PWD"
# error with backslash, even ones which do not need to be: "/a-b" -> "/a\-b"
# error glob() should unbackslash them and match. uClibc does not unbackslash,
# error fails to match dirname, subsequently not expanding <pattern> in it.
// Testcase:
// if (glob("/etc/polkit\\-1", 0, NULL, &pglob)) - this returns 0 on uclibc, no bug
// if (glob("/etc/polkit\\-1/*", 0, NULL, &pglob)) printf("uclibc bug!\n");
#endif
#if !ENABLE_ASH_INTERNAL_GLOB
# include <glob.h>
#endif
#include "unicode.h"
#include "shell_common.h"
#if ENABLE_FEATURE_SH_MATH
# include "math.h"
#endif
#if ENABLE_ASH_RANDOM_SUPPORT
# include "random.h"
#else
# define CLEAR_RANDOM_T(rnd) ((void)0)
#endif
#include "NUM_APPLETS.h"
#if NUM_APPLETS == 1
/* STANDALONE does not make sense, and won't compile */
# undef CONFIG_FEATURE_SH_STANDALONE
# undef ENABLE_FEATURE_SH_STANDALONE
# undef IF_FEATURE_SH_STANDALONE
# undef IF_NOT_FEATURE_SH_STANDALONE
# define ENABLE_FEATURE_SH_STANDALONE 0
# define IF_FEATURE_SH_STANDALONE(...)
# define IF_NOT_FEATURE_SH_STANDALONE(...) __VA_ARGS__
#endif
#ifndef PIPE_BUF
# define PIPE_BUF 4096 /* amount of buffering in a pipe */
#endif
#if !BB_MMU
# error "Do not even bother, ash will not run on NOMMU machine"
#endif
/* ============ Hash table sizes. Configurable. */
#define VTABSIZE 39
#define ATABSIZE 39
#define CMDTABLESIZE 31 /* should be prime */
/* ============ Shell options */
static const char *const optletters_optnames[] = {
"e" "errexit",
"f" "noglob",
"I" "ignoreeof",
"i" "interactive",
"m" "monitor",
"n" "noexec",
"s" "stdin",
"x" "xtrace",
"v" "verbose",
"C" "noclobber",
"a" "allexport",
"b" "notify",
"u" "nounset",
"\0" "vi"
#if ENABLE_ASH_BASH_COMPAT
,"\0" "pipefail"
#endif
#if DEBUG
,"\0" "nolog"
,"\0" "debug"
#endif
};
#define optletters(n) optletters_optnames[n][0]
#define optnames(n) (optletters_optnames[n] + 1)
enum { NOPTS = ARRAY_SIZE(optletters_optnames) };
/* ============ Misc data */
#define msg_illnum "Illegal number: %s"
/*
* We enclose jmp_buf in a structure so that we can declare pointers to
* jump locations. The global variable handler contains the location to
* jump to when an exception occurs, and the global variable exception_type
* contains a code identifying the exception. To implement nested
* exception handlers, the user should save the value of handler on entry
* to an inner scope, set handler to point to a jmploc structure for the
* inner scope, and restore handler on exit from the scope.
*/
struct jmploc {
jmp_buf loc;
};
struct globals_misc {
uint8_t exitstatus; /* exit status of last command */
uint8_t back_exitstatus;/* exit status of backquoted command */
smallint job_warning; /* user was warned about stopped jobs (can be 2, 1 or 0). */
int rootpid; /* pid of main shell */
/* shell level: 0 for the main shell, 1 for its children, and so on */
int shlvl;
#define rootshell (!shlvl)
char *minusc; /* argument to -c option */
char *curdir; // = nullstr; /* current working directory */
char *physdir; // = nullstr; /* physical working directory */
char *arg0; /* value of $0 */
struct jmploc *exception_handler;
volatile int suppress_int; /* counter */
volatile /*sig_atomic_t*/ smallint pending_int; /* 1 = got SIGINT */
volatile /*sig_atomic_t*/ smallint got_sigchld; /* 1 = got SIGCHLD */
volatile /*sig_atomic_t*/ smallint pending_sig; /* last pending signal */
smallint exception_type; /* kind of exception (0..5) */
/* exceptions */
#define EXINT 0 /* SIGINT received */
#define EXERROR 1 /* a generic error */
#define EXEXIT 4 /* exit the shell */
smallint isloginsh;
char nullstr[1]; /* zero length string */
char optlist[NOPTS];
#define eflag optlist[0]
#define fflag optlist[1]
#define Iflag optlist[2]
#define iflag optlist[3]
#define mflag optlist[4]
#define nflag optlist[5]
#define sflag optlist[6]
#define xflag optlist[7]
#define vflag optlist[8]
#define Cflag optlist[9]
#define aflag optlist[10]
#define bflag optlist[11]
#define uflag optlist[12]
#define viflag optlist[13]
#if ENABLE_ASH_BASH_COMPAT
# define pipefail optlist[14]
#else
# define pipefail 0
#endif
#if DEBUG
# define nolog optlist[14 + ENABLE_ASH_BASH_COMPAT]
# define debug optlist[15 + ENABLE_ASH_BASH_COMPAT]
#endif
/* trap handler commands */
/*
* Sigmode records the current value of the signal handlers for the various
* modes. A value of zero means that the current handler is not known.
* S_HARD_IGN indicates that the signal was ignored on entry to the shell.
*/
char sigmode[NSIG - 1];
#define S_DFL 1 /* default signal handling (SIG_DFL) */
#define S_CATCH 2 /* signal is caught */
#define S_IGN 3 /* signal is ignored (SIG_IGN) */
#define S_HARD_IGN 4 /* signal is ignored permanently */
/* indicates specified signal received */
uint8_t gotsig[NSIG - 1]; /* offset by 1: "signal" 0 is meaningless */
uint8_t may_have_traps; /* 0: definitely no traps are set, 1: some traps may be set */
char *trap[NSIG];
char **trap_ptr; /* used only by "trap hack" */
/* Rarely referenced stuff */
#if ENABLE_ASH_RANDOM_SUPPORT
random_t random_gen;
#endif
pid_t backgndpid; /* pid of last background process */
};
extern struct globals_misc *const ash_ptr_to_globals_misc;
#define G_misc (*ash_ptr_to_globals_misc)
#define exitstatus (G_misc.exitstatus )
#define back_exitstatus (G_misc.back_exitstatus )
#define job_warning (G_misc.job_warning)
#define rootpid (G_misc.rootpid )
#define shlvl (G_misc.shlvl )
#define minusc (G_misc.minusc )
#define curdir (G_misc.curdir )
#define physdir (G_misc.physdir )
#define arg0 (G_misc.arg0 )
#define exception_handler (G_misc.exception_handler)
#define exception_type (G_misc.exception_type )
#define suppress_int (G_misc.suppress_int )
#define pending_int (G_misc.pending_int )
#define got_sigchld (G_misc.got_sigchld )
#define pending_sig (G_misc.pending_sig )
#define isloginsh (G_misc.isloginsh )
#define nullstr (G_misc.nullstr )
#define optlist (G_misc.optlist )
#define sigmode (G_misc.sigmode )
#define gotsig (G_misc.gotsig )
#define may_have_traps (G_misc.may_have_traps )
#define trap (G_misc.trap )
#define trap_ptr (G_misc.trap_ptr )
#define random_gen (G_misc.random_gen )
#define backgndpid (G_misc.backgndpid )
#define INIT_G_misc() do { \
(*(struct globals_misc**)&ash_ptr_to_globals_misc) = xzalloc(sizeof(G_misc)); \
barrier(); \
curdir = nullstr; \
physdir = nullstr; \
trap_ptr = trap; \
} while (0)
/* ============ DEBUG */
#if DEBUG
static void trace_printf(const char *fmt, ...);
static void trace_vprintf(const char *fmt, va_list va);
# define TRACE(param) trace_printf param
# define TRACEV(param) trace_vprintf param
# define close(fd) do { \
int dfd = (fd); \
if (close(dfd) < 0) \
bb_error_msg("bug on %d: closing %d(0x%x)", \
__LINE__, dfd, dfd); \
} while (0)
#else
# define TRACE(param)
# define TRACEV(param)
#endif
/* ============ Utility functions */
#define is_name(c) ((c) == '_' || isalpha((unsigned char)(c)))
#define is_in_name(c) ((c) == '_' || isalnum((unsigned char)(c)))
static int
isdigit_str9(const char *str)
{
int maxlen = 9 + 1; /* max 9 digits: 999999999 */
while (--maxlen && isdigit(*str))
str++;
return (*str == '\0');
}
static const char *
var_end(const char *var)
{
while (*var)
if (*var++ == '=')
break;
return var;
}
/* ============ Interrupts / exceptions */
static void exitshell(void) NORETURN;
/*
* These macros allow the user to suspend the handling of interrupt signals
* over a period of time. This is similar to SIGHOLD or to sigblock, but
* much more efficient and portable. (But hacking the kernel is so much
* more fun than worrying about efficiency and portability. :-))
*/
#if DEBUG_INTONOFF
# define INT_OFF do { \
TRACE(("%s:%d INT_OFF(%d)\n", __func__, __LINE__, suppress_int)); \
suppress_int++; \
barrier(); \
} while (0)
#else
# define INT_OFF do { \
suppress_int++; \
barrier(); \
} while (0)
#endif
/*
* Called to raise an exception. Since C doesn't include exceptions, we
* just do a longjmp to the exception handler. The type of exception is
* stored in the global variable "exception_type".
*/
static void raise_exception(int) NORETURN;
static void
raise_exception(int e)
{
#if DEBUG
if (exception_handler == NULL)
abort();
#endif
INT_OFF;
exception_type = e;
longjmp(exception_handler->loc, 1);
}
#if DEBUG
#define raise_exception(e) do { \
TRACE(("raising exception %d on line %d\n", (e), __LINE__)); \
raise_exception(e); \
} while (0)
#endif
/*
* Called when a SIGINT is received. (If the user specifies
* that SIGINT is to be trapped or ignored using the trap builtin, then
* this routine is not called.) Suppressint is nonzero when interrupts
* are held using the INT_OFF macro. (The test for iflag is just
* defensive programming.)
*/
static void raise_interrupt(void) NORETURN;
static void
raise_interrupt(void)
{
pending_int = 0;
/* Signal is not automatically unmasked after it is raised,
* do it ourself - unmask all signals */
sigprocmask_allsigs(SIG_UNBLOCK);
/* pending_sig = 0; - now done in signal_handler() */
if (!(rootshell && iflag)) {
/* Kill ourself with SIGINT */
signal(SIGINT, SIG_DFL);
raise(SIGINT);
}
/* bash: ^C even on empty command line sets $? */
exitstatus = SIGINT + 128;
raise_exception(EXINT);
/* NOTREACHED */
}
#if DEBUG
#define raise_interrupt() do { \
TRACE(("raising interrupt on line %d\n", __LINE__)); \
raise_interrupt(); \
} while (0)
#endif
static IF_ASH_OPTIMIZE_FOR_SIZE(inline) void
int_on(void)
{
barrier();
if (--suppress_int == 0 && pending_int) {
raise_interrupt();
}
}
#if DEBUG_INTONOFF
# define INT_ON do { \
TRACE(("%s:%d INT_ON(%d)\n", __func__, __LINE__, suppress_int-1)); \
int_on(); \
} while (0)
#else
# define INT_ON int_on()
#endif
static IF_ASH_OPTIMIZE_FOR_SIZE(inline) void
force_int_on(void)
{
barrier();
suppress_int = 0;
if (pending_int)
raise_interrupt();
}
#define FORCE_INT_ON force_int_on()
#define SAVE_INT(v) ((v) = suppress_int)
#define RESTORE_INT(v) do { \
barrier(); \
suppress_int = (v); \
if (suppress_int == 0 && pending_int) \
raise_interrupt(); \
} while (0)
/* ============ Stdout/stderr output */
static void
outstr(const char *p, FILE *file)
{
INT_OFF;
fputs(p, file);
INT_ON;
}
static void
flush_stdout_stderr(void)
{
INT_OFF;
fflush_all();
INT_ON;
}
/* Was called outcslow(c,FILE*), but c was always '\n' */
static void
newline_and_flush(FILE *dest)
{
INT_OFF;
putc('\n', dest);
fflush(dest);
INT_ON;
}
static int out1fmt(const char *, ...) __attribute__((__format__(__printf__,1,2)));
static int
out1fmt(const char *fmt, ...)
{
va_list ap;
int r;
INT_OFF;
va_start(ap, fmt);
r = vprintf(fmt, ap);
va_end(ap);
INT_ON;
return r;
}
static int fmtstr(char *, size_t, const char *, ...) __attribute__((__format__(__printf__,3,4)));
static int
fmtstr(char *outbuf, size_t length, const char *fmt, ...)
{
va_list ap;
int ret;
va_start(ap, fmt);
INT_OFF;
ret = vsnprintf(outbuf, length, fmt, ap);
va_end(ap);
INT_ON;
return ret;
}
static void
out1str(const char *p)
{
outstr(p, stdout);
}
static void
out2str(const char *p)
{
outstr(p, stderr);
flush_stdout_stderr();
}
/* ============ Parser structures */
/* control characters in argument strings */
#define CTL_FIRST CTLESC
#define CTLESC ((unsigned char)'\201') /* escape next character */
#define CTLVAR ((unsigned char)'\202') /* variable defn */
#define CTLENDVAR ((unsigned char)'\203')
#define CTLBACKQ ((unsigned char)'\204')
#define CTLARI ((unsigned char)'\206') /* arithmetic expression */
#define CTLENDARI ((unsigned char)'\207')
#define CTLQUOTEMARK ((unsigned char)'\210')
#define CTL_LAST CTLQUOTEMARK
/* variable substitution byte (follows CTLVAR) */
#define VSTYPE 0x0f /* type of variable substitution */
#define VSNUL 0x10 /* colon--treat the empty string as unset */
/* values of VSTYPE field */
#define VSNORMAL 0x1 /* normal variable: $var or ${var} */
#define VSMINUS 0x2 /* ${var-text} */
#define VSPLUS 0x3 /* ${var+text} */
#define VSQUESTION 0x4 /* ${var?message} */
#define VSASSIGN 0x5 /* ${var=text} */
#define VSTRIMRIGHT 0x6 /* ${var%pattern} */
#define VSTRIMRIGHTMAX 0x7 /* ${var%%pattern} */
#define VSTRIMLEFT 0x8 /* ${var#pattern} */
#define VSTRIMLEFTMAX 0x9 /* ${var##pattern} */
#define VSLENGTH 0xa /* ${#var} */
#if ENABLE_ASH_BASH_COMPAT
#define VSSUBSTR 0xc /* ${var:position:length} */
#define VSREPLACE 0xd /* ${var/pattern/replacement} */
#define VSREPLACEALL 0xe /* ${var//pattern/replacement} */
#endif
static const char dolatstr[] ALIGN1 = {
CTLQUOTEMARK, CTLVAR, VSNORMAL, '@', '=', CTLQUOTEMARK, '\0'
};
#define DOLATSTRLEN 6
#define NCMD 0
#define NPIPE 1
#define NREDIR 2
#define NBACKGND 3
#define NSUBSHELL 4
#define NAND 5
#define NOR 6
#define NSEMI 7
#define NIF 8
#define NWHILE 9
#define NUNTIL 10
#define NFOR 11
#define NCASE 12
#define NCLIST 13
#define NDEFUN 14
#define NARG 15
#define NTO 16
#if ENABLE_ASH_BASH_COMPAT
#define NTO2 17
#endif
#define NCLOBBER 18
#define NFROM 19
#define NFROMTO 20
#define NAPPEND 21
#define NTOFD 22
#define NFROMFD 23
#define NHERE 24
#define NXHERE 25
#define NNOT 26
#define N_NUMBER 27
union node;
struct ncmd {
smallint type; /* Nxxxx */
union node *assign;
union node *args;
union node *redirect;
};
struct npipe {
smallint type;
smallint pipe_backgnd;
struct nodelist *cmdlist;
};
struct nredir {
smallint type;
union node *n;
union node *redirect;
};
struct nbinary {
smallint type;
union node *ch1;
union node *ch2;
};
struct nif {
smallint type;
union node *test;
union node *ifpart;
union node *elsepart;
};
struct nfor {
smallint type;
union node *args;
union node *body;
char *var;
};
struct ncase {
smallint type;
union node *expr;
union node *cases;
};
struct nclist {
smallint type;
union node *next;
union node *pattern;
union node *body;
};
struct narg {
smallint type;
union node *next;
char *text;
struct nodelist *backquote;
};
/* nfile and ndup layout must match!
* NTOFD (>&fdnum) uses ndup structure, but we may discover mid-flight
* that it is actually NTO2 (>&file), and change its type.
*/
struct nfile {
smallint type;
union node *next;
int fd;
int _unused_dupfd;
union node *fname;
char *expfname;
};
struct ndup {
smallint type;
union node *next;
int fd;
int dupfd;
union node *vname;
char *_unused_expfname;
};
struct nhere {
smallint type;
union node *next;
int fd;
union node *doc;
};
struct nnot {
smallint type;
union node *com;
};
union node {
smallint type;
struct ncmd ncmd;
struct npipe npipe;
struct nredir nredir;
struct nbinary nbinary;
struct nif nif;
struct nfor nfor;
struct ncase ncase;
struct nclist nclist;
struct narg narg;
struct nfile nfile;
struct ndup ndup;
struct nhere nhere;
struct nnot nnot;
};
/*
* NODE_EOF is returned by parsecmd when it encounters an end of file.
* It must be distinct from NULL.
*/
#define NODE_EOF ((union node *) -1L)
struct nodelist {
struct nodelist *next;
union node *n;
};
struct funcnode {
int count;
union node n;
};
/*
* Free a parse tree.
*/
static void
freefunc(struct funcnode *f)
{
if (f && --f->count < 0)
free(f);
}
/* ============ Debugging output */
#if DEBUG
static FILE *tracefile;
static void
trace_printf(const char *fmt, ...)
{
va_list va;
if (debug != 1)
return;
if (DEBUG_TIME)
fprintf(tracefile, "%u ", (int) time(NULL));
if (DEBUG_PID)
fprintf(tracefile, "[%u] ", (int) getpid());
if (DEBUG_SIG)
fprintf(tracefile, "pending s:%d i:%d(supp:%d) ", pending_sig, pending_int, suppress_int);
va_start(va, fmt);
vfprintf(tracefile, fmt, va);
va_end(va);
}
static void
trace_vprintf(const char *fmt, va_list va)
{
if (debug != 1)
return;
vfprintf(tracefile, fmt, va);
fprintf(tracefile, "\n");
}
static void
trace_puts(const char *s)
{
if (debug != 1)
return;
fputs(s, tracefile);
}
static void
trace_puts_quoted(char *s)
{
char *p;
char c;
if (debug != 1)
return;
putc('"', tracefile);
for (p = s; *p; p++) {
switch ((unsigned char)*p) {
case '\n': c = 'n'; goto backslash;
case '\t': c = 't'; goto backslash;
case '\r': c = 'r'; goto backslash;
case '\"': c = '\"'; goto backslash;
case '\\': c = '\\'; goto backslash;
case CTLESC: c = 'e'; goto backslash;
case CTLVAR: c = 'v'; goto backslash;
case CTLBACKQ: c = 'q'; goto backslash;
backslash:
putc('\\', tracefile);
putc(c, tracefile);
break;
default:
if (*p >= ' ' && *p <= '~')
putc(*p, tracefile);
else {
putc('\\', tracefile);
putc((*p >> 6) & 03, tracefile);
putc((*p >> 3) & 07, tracefile);
putc(*p & 07, tracefile);
}
break;
}
}
putc('"', tracefile);
}
static void
trace_puts_args(char **ap)
{
if (debug != 1)
return;
if (!*ap)
return;
while (1) {
trace_puts_quoted(*ap);
if (!*++ap) {
putc('\n', tracefile);
break;
}
putc(' ', tracefile);
}
}
static void
opentrace(void)
{
char s[100];
#ifdef O_APPEND
int flags;
#endif
if (debug != 1) {
if (tracefile)
fflush(tracefile);
/* leave open because libedit might be using it */
return;
}
strcpy(s, "./trace");
if (tracefile) {
if (!freopen(s, "a", tracefile)) {
fprintf(stderr, "Can't re-open %s\n", s);
debug = 0;
return;
}
} else {
tracefile = fopen(s, "a");
if (tracefile == NULL) {
fprintf(stderr, "Can't open %s\n", s);
debug = 0;
return;
}
}
#ifdef O_APPEND
flags = fcntl(fileno(tracefile), F_GETFL);
if (flags >= 0)
fcntl(fileno(tracefile), F_SETFL, flags | O_APPEND);
#endif
setlinebuf(tracefile);
fputs("\nTracing started.\n", tracefile);
}
static void
indent(int amount, char *pfx, FILE *fp)
{
int i;
for (i = 0; i < amount; i++) {
if (pfx && i == amount - 1)
fputs(pfx, fp);
putc('\t', fp);
}
}
/* little circular references here... */
static void shtree(union node *n, int ind, char *pfx, FILE *fp);
static void
sharg(union node *arg, FILE *fp)
{
char *p;
struct nodelist *bqlist;
unsigned char subtype;
if (arg->type != NARG) {
out1fmt("<node type %d>\n", arg->type);
abort();
}
bqlist = arg->narg.backquote;
for (p = arg->narg.text; *p; p++) {
switch ((unsigned char)*p) {
case CTLESC:
p++;
putc(*p, fp);
break;
case CTLVAR:
putc('$', fp);
putc('{', fp);
subtype = *++p;
if (subtype == VSLENGTH)
putc('#', fp);
while (*p != '=') {
putc(*p, fp);
p++;
}
if (subtype & VSNUL)
putc(':', fp);
switch (subtype & VSTYPE) {
case VSNORMAL:
putc('}', fp);
break;
case VSMINUS:
putc('-', fp);
break;
case VSPLUS:
putc('+', fp);
break;
case VSQUESTION:
putc('?', fp);
break;
case VSASSIGN:
putc('=', fp);
break;
case VSTRIMLEFT:
putc('#', fp);
break;
case VSTRIMLEFTMAX:
putc('#', fp);
putc('#', fp);
break;
case VSTRIMRIGHT:
putc('%', fp);
break;
case VSTRIMRIGHTMAX:
putc('%', fp);
putc('%', fp);
break;
case VSLENGTH:
break;
default:
out1fmt("<subtype %d>", subtype);
}
break;
case CTLENDVAR:
putc('}', fp);
break;
case CTLBACKQ:
putc('$', fp);
putc('(', fp);
shtree(bqlist->n, -1, NULL, fp);
putc(')', fp);
break;
default:
putc(*p, fp);
break;
}
}
}
static void
shcmd(union node *cmd, FILE *fp)
{
union node *np;
int first;
const char *s;
int dftfd;
first = 1;
for (np = cmd->ncmd.args; np; np = np->narg.next) {
if (!first)
putc(' ', fp);
sharg(np, fp);
first = 0;
}
for (np = cmd->ncmd.redirect; np; np = np->nfile.next) {
if (!first)
putc(' ', fp);
dftfd = 0;
switch (np->nfile.type) {
case NTO: s = ">>"+1; dftfd = 1; break;
case NCLOBBER: s = ">|"; dftfd = 1; break;
case NAPPEND: s = ">>"; dftfd = 1; break;
#if ENABLE_ASH_BASH_COMPAT
case NTO2:
#endif
case NTOFD: s = ">&"; dftfd = 1; break;
case NFROM: s = "<"; break;
case NFROMFD: s = "<&"; break;
case NFROMTO: s = "<>"; break;
default: s = "*error*"; break;
}
if (np->nfile.fd != dftfd)
fprintf(fp, "%d", np->nfile.fd);
fputs(s, fp);
if (np->nfile.type == NTOFD || np->nfile.type == NFROMFD) {
fprintf(fp, "%d", np->ndup.dupfd);
} else {
sharg(np->nfile.fname, fp);
}
first = 0;
}
}
static void
shtree(union node *n, int ind, char *pfx, FILE *fp)
{
struct nodelist *lp;
const char *s;
if (n == NULL)
return;
indent(ind, pfx, fp);
if (n == NODE_EOF) {
fputs("<EOF>", fp);
return;
}
switch (n->type) {
case NSEMI:
s = "; ";
goto binop;
case NAND:
s = " && ";
goto binop;
case NOR:
s = " || ";
binop:
shtree(n->nbinary.ch1, ind, NULL, fp);
/* if (ind < 0) */
fputs(s, fp);
shtree(n->nbinary.ch2, ind, NULL, fp);
break;
case NCMD:
shcmd(n, fp);
if (ind >= 0)
putc('\n', fp);
break;
case NPIPE:
for (lp = n->npipe.cmdlist; lp; lp = lp->next) {
shtree(lp->n, 0, NULL, fp);
if (lp->next)
fputs(" | ", fp);
}
if (n->npipe.pipe_backgnd)
fputs(" &", fp);
if (ind >= 0)
putc('\n', fp);
break;
default:
fprintf(fp, "<node type %d>", n->type);
if (ind >= 0)
putc('\n', fp);
break;
}
}
static void
showtree(union node *n)
{
trace_puts("showtree called\n");
shtree(n, 1, NULL, stderr);
}
#endif /* DEBUG */
/* ============ Parser data */
/*
* ash_vmsg() needs parsefile->fd, hence parsefile definition is moved up.
*/
struct strlist {
struct strlist *next;
char *text;
};
struct alias;
struct strpush {
struct strpush *prev; /* preceding string on stack */
char *prev_string;
int prev_left_in_line;
#if ENABLE_ASH_ALIAS
struct alias *ap; /* if push was associated with an alias */
#endif
char *string; /* remember the string since it may change */
/* Remember last two characters for pungetc. */
int lastc[2];
/* Number of outstanding calls to pungetc. */
int unget;
};
struct parsefile {
struct parsefile *prev; /* preceding file on stack */
int linno; /* current line */
int pf_fd; /* file descriptor (or -1 if string) */
int left_in_line; /* number of chars left in this line */
int left_in_buffer; /* number of chars left in this buffer past the line */
char *next_to_pgetc; /* next char in buffer */
char *buf; /* input buffer */
struct strpush *strpush; /* for pushing strings at this level */
struct strpush basestrpush; /* so pushing one is fast */
/* Remember last two characters for pungetc. */
int lastc[2];
/* Number of outstanding calls to pungetc. */
int unget;
};
static struct parsefile basepf; /* top level input file */
static struct parsefile *g_parsefile = &basepf; /* current input file */
static int startlinno; /* line # where last token started */
static char *commandname; /* currently executing command */
static struct strlist *cmdenviron; /* environment for builtin command */
/* ============ Message printing */
static void
ash_vmsg(const char *msg, va_list ap)
{
fprintf(stderr, "%s: ", arg0);
if (commandname) {
if (strcmp(arg0, commandname))
fprintf(stderr, "%s: ", commandname);
if (!iflag || g_parsefile->pf_fd > 0)
fprintf(stderr, "line %d: ", startlinno);
}
vfprintf(stderr, msg, ap);
newline_and_flush(stderr);
}
/*
* Exverror is called to raise the error exception. If the second argument
* is not NULL then error prints an error message using printf style
* formatting. It then raises the error exception.
*/
static void ash_vmsg_and_raise(int, const char *, va_list) NORETURN;
static void
ash_vmsg_and_raise(int cond, const char *msg, va_list ap)
{
#if DEBUG
if (msg) {
TRACE(("ash_vmsg_and_raise(%d):", cond));
TRACEV((msg, ap));
} else
TRACE(("ash_vmsg_and_raise(%d):NULL\n", cond));
if (msg)
#endif
ash_vmsg(msg, ap);
flush_stdout_stderr();
raise_exception(cond);
/* NOTREACHED */
}
static void ash_msg_and_raise_error(const char *, ...) NORETURN;
static void
ash_msg_and_raise_error(const char *msg, ...)
{
va_list ap;
va_start(ap, msg);
ash_vmsg_and_raise(EXERROR, msg, ap);
/* NOTREACHED */
va_end(ap);
}
static void raise_error_syntax(const char *) NORETURN;
static void
raise_error_syntax(const char *msg)
{
ash_msg_and_raise_error("syntax error: %s", msg);
/* NOTREACHED */
}
static void ash_msg_and_raise(int, const char *, ...) NORETURN;
static void
ash_msg_and_raise(int cond, const char *msg, ...)
{
va_list ap;
va_start(ap, msg);
ash_vmsg_and_raise(cond, msg, ap);
/* NOTREACHED */
va_end(ap);
}
/*
* error/warning routines for external builtins
*/
static void
ash_msg(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
ash_vmsg(fmt, ap);
va_end(ap);
}
/*
* Return a string describing an error. The returned string may be a
* pointer to a static buffer that will be overwritten on the next call.
* Action describes the operation that got the error.
*/
static const char *
errmsg(int e, const char *em)
{
if (e == ENOENT || e == ENOTDIR) {
return em;
}
return strerror(e);
}
/* ============ Memory allocation */
#if 0
/* I consider these wrappers nearly useless:
* ok, they return you to nearest exception handler, but
* how much memory do you leak in the process, making
* memory starvation worse?
*/
static void *
ckrealloc(void * p, size_t nbytes)
{
p = realloc(p, nbytes);
if (!p)
ash_msg_and_raise_error(bb_msg_memory_exhausted);
return p;
}
static void *
ckmalloc(size_t nbytes)
{
return ckrealloc(NULL, nbytes);
}
static void *
ckzalloc(size_t nbytes)
{
return memset(ckmalloc(nbytes), 0, nbytes);
}
static char *
ckstrdup(const char *s)
{
char *p = strdup(s);
if (!p)
ash_msg_and_raise_error(bb_msg_memory_exhausted);
return p;
}
#else
/* Using bbox equivalents. They exit if out of memory */
# define ckrealloc xrealloc
# define ckmalloc xmalloc
# define ckzalloc xzalloc
# define ckstrdup xstrdup
#endif
/*
* It appears that grabstackstr() will barf with such alignments
* because stalloc() will return a string allocated in a new stackblock.
*/
#define SHELL_ALIGN(nbytes) (((nbytes) + SHELL_SIZE) & ~SHELL_SIZE)
enum {
/* Most machines require the value returned from malloc to be aligned
* in some way. The following macro will get this right
* on many machines. */
SHELL_SIZE = sizeof(union { int i; char *cp; double d; }) - 1,
/* Minimum size of a block */
MINSIZE = SHELL_ALIGN(504),
};
struct stack_block {
struct stack_block *prev;
char space[MINSIZE];
};
struct stackmark {
struct stack_block *stackp;
char *stacknxt;
size_t stacknleft;
};
struct globals_memstack {
struct stack_block *g_stackp; // = &stackbase;
char *g_stacknxt; // = stackbase.space;
char *sstrend; // = stackbase.space + MINSIZE;
size_t g_stacknleft; // = MINSIZE;
struct stack_block stackbase;
};
extern struct globals_memstack *const ash_ptr_to_globals_memstack;
#define G_memstack (*ash_ptr_to_globals_memstack)
#define g_stackp (G_memstack.g_stackp )
#define g_stacknxt (G_memstack.g_stacknxt )
#define sstrend (G_memstack.sstrend )
#define g_stacknleft (G_memstack.g_stacknleft)
#define stackbase (G_memstack.stackbase )
#define INIT_G_memstack() do { \
(*(struct globals_memstack**)&ash_ptr_to_globals_memstack) = xzalloc(sizeof(G_memstack)); \
barrier(); \
g_stackp = &stackbase; \
g_stacknxt = stackbase.space; \
g_stacknleft = MINSIZE; \
sstrend = stackbase.space + MINSIZE; \
} while (0)
#define stackblock() ((void *)g_stacknxt)
#define stackblocksize() g_stacknleft
/*
* Parse trees for commands are allocated in lifo order, so we use a stack
* to make this more efficient, and also to avoid all sorts of exception
* handling code to handle interrupts in the middle of a parse.
*
* The size 504 was chosen because the Ultrix malloc handles that size
* well.
*/
static void *
stalloc(size_t nbytes)
{
char *p;
size_t aligned;
aligned = SHELL_ALIGN(nbytes);
if (aligned > g_stacknleft) {
size_t len;
size_t blocksize;
struct stack_block *sp;
blocksize = aligned;
if (blocksize < MINSIZE)
blocksize = MINSIZE;
len = sizeof(struct stack_block) - MINSIZE + blocksize;
if (len < blocksize)
ash_msg_and_raise_error(bb_msg_memory_exhausted);
INT_OFF;
sp = ckmalloc(len);
sp->prev = g_stackp;
g_stacknxt = sp->space;
g_stacknleft = blocksize;
sstrend = g_stacknxt + blocksize;
g_stackp = sp;
INT_ON;
}
p = g_stacknxt;
g_stacknxt += aligned;
g_stacknleft -= aligned;
return p;
}
static void *
stzalloc(size_t nbytes)
{
return memset(stalloc(nbytes), 0, nbytes);
}
static void
stunalloc(void *p)
{
#if DEBUG
if (!p || (g_stacknxt < (char *)p) || ((char *)p < g_stackp->space)) {
write(STDERR_FILENO, "stunalloc\n", 10);
abort();
}
#endif
g_stacknleft += g_stacknxt - (char *)p;
g_stacknxt = p;
}
/*
* Like strdup but works with the ash stack.
*/
static char *
sstrdup(const char *p)
{
size_t len = strlen(p) + 1;
return memcpy(stalloc(len), p, len);
}
static inline void
grabstackblock(size_t len)
{
stalloc(len);
}
static void
pushstackmark(struct stackmark *mark, size_t len)
{
mark->stackp = g_stackp;
mark->stacknxt = g_stacknxt;
mark->stacknleft = g_stacknleft;
grabstackblock(len);
}
static void
setstackmark(struct stackmark *mark)
{
pushstackmark(mark, g_stacknxt == g_stackp->space && g_stackp != &stackbase);
}
static void
popstackmark(struct stackmark *mark)
{
struct stack_block *sp;
if (!mark->stackp)
return;
INT_OFF;
while (g_stackp != mark->stackp) {
sp = g_stackp;
g_stackp = sp->prev;
free(sp);
}
g_stacknxt = mark->stacknxt;
g_stacknleft = mark->stacknleft;
sstrend = mark->stacknxt + mark->stacknleft;
INT_ON;
}
/*
* When the parser reads in a string, it wants to stick the string on the
* stack and only adjust the stack pointer when it knows how big the
* string is. Stackblock (defined in stack.h) returns a pointer to a block
* of space on top of the stack and stackblocklen returns the length of
* this block. Growstackblock will grow this space by at least one byte,
* possibly moving it (like realloc). Grabstackblock actually allocates the
* part of the block that has been used.
*/
static void
growstackblock(void)
{
size_t newlen;
newlen = g_stacknleft * 2;
if (newlen < g_stacknleft)
ash_msg_and_raise_error(bb_msg_memory_exhausted);
if (newlen < 128)
newlen += 128;
if (g_stacknxt == g_stackp->space && g_stackp != &stackbase) {
struct stack_block *sp;
struct stack_block *prevstackp;
size_t grosslen;
INT_OFF;
sp = g_stackp;
prevstackp = sp->prev;
grosslen = newlen + sizeof(struct stack_block) - MINSIZE;
sp = ckrealloc(sp, grosslen);
sp->prev = prevstackp;
g_stackp = sp;
g_stacknxt = sp->space;
g_stacknleft = newlen;
sstrend = sp->space + newlen;
INT_ON;
} else {
char *oldspace = g_stacknxt;
size_t oldlen = g_stacknleft;
char *p = stalloc(newlen);
/* free the space we just allocated */
g_stacknxt = memcpy(p, oldspace, oldlen);
g_stacknleft += newlen;
}
}
/*
* The following routines are somewhat easier to use than the above.
* The user declares a variable of type STACKSTR, which may be declared
* to be a register. The macro STARTSTACKSTR initializes things. Then
* the user uses the macro STPUTC to add characters to the string. In
* effect, STPUTC(c, p) is the same as *p++ = c except that the stack is
* grown as necessary. When the user is done, she can just leave the
* string there and refer to it using stackblock(). Or she can allocate
* the space for it using grabstackstr(). If it is necessary to allow
* someone else to use the stack temporarily and then continue to grow
* the string, the user should use grabstack to allocate the space, and
* then call ungrabstr(p) to return to the previous mode of operation.
*
* USTPUTC is like STPUTC except that it doesn't check for overflow.
* CHECKSTACKSPACE can be called before USTPUTC to ensure that there
* is space for at least one character.
*/
static void *
growstackstr(void)
{
size_t len = stackblocksize();
growstackblock();
return (char *)stackblock() + len;
}
/*
* Called from CHECKSTRSPACE.
*/
static char *
makestrspace(size_t newlen, char *p)
{
size_t len = p - g_stacknxt;
size_t size;
for (;;) {
size_t nleft;
size = stackblocksize();
nleft = size - len;
if (nleft >= newlen)
break;
growstackblock();
}
return (char *)stackblock() + len;
}
static char *
stack_nputstr(const char *s, size_t n, char *p)
{
p = makestrspace(n, p);
p = (char *)memcpy(p, s, n) + n;
return p;
}
static char *
stack_putstr(const char *s, char *p)
{
return stack_nputstr(s, strlen(s), p);
}
static char *
_STPUTC(int c, char *p)
{
if (p == sstrend)
p = growstackstr();
*p++ = c;
return p;
}
#define STARTSTACKSTR(p) ((p) = stackblock())
#define STPUTC(c, p) ((p) = _STPUTC((c), (p)))
#define CHECKSTRSPACE(n, p) do { \
char *q = (p); \
size_t l = (n); \
size_t m = sstrend - q; \
if (l > m) \
(p) = makestrspace(l, q); \
} while (0)
#define USTPUTC(c, p) (*(p)++ = (c))
#define STACKSTRNUL(p) do { \
if ((p) == sstrend) \
(p) = growstackstr(); \
*(p) = '\0'; \
} while (0)
#define STUNPUTC(p) (--(p))
#define STTOPC(p) ((p)[-1])
#define STADJUST(amount, p) ((p) += (amount))
#define grabstackstr(p) stalloc((char *)(p) - (char *)stackblock())
#define ungrabstackstr(s, p) stunalloc(s)
#define stackstrend() ((void *)sstrend)
/* ============ String helpers */
/*
* prefix -- see if pfx is a prefix of string.
*/
static char *
prefix(const char *string, const char *pfx)
{
while (*pfx) {
if (*pfx++ != *string++)
return NULL;
}
return (char *) string;
}
/*
* Check for a valid number. This should be elsewhere.
*/
static int
is_number(const char *p)
{
do {
if (!isdigit(*p))
return 0;
} while (*++p != '\0');
return 1;
}
/*
* Convert a string of digits to an integer, printing an error message on
* failure.
*/
static int
number(const char *s)
{
if (!is_number(s))
ash_msg_and_raise_error(msg_illnum, s);
return atoi(s);
}
/*
* Produce a possibly single quoted string suitable as input to the shell.
* The return string is allocated on the stack.
*/
static char *
single_quote(const char *s)
{
char *p;
STARTSTACKSTR(p);
do {
char *q;
size_t len;
len = strchrnul(s, '\'') - s;
q = p = makestrspace(len + 3, p);
*q++ = '\'';
q = (char *)memcpy(q, s, len) + len;
*q++ = '\'';
s += len;
STADJUST(q - p, p);
if (*s != '\'')
break;
len = 0;
do len++; while (*++s == '\'');
q = p = makestrspace(len + 3, p);
*q++ = '"';
q = (char *)memcpy(q, s - len, len) + len;
*q++ = '"';
STADJUST(q - p, p);
} while (*s);
USTPUTC('\0', p);
return stackblock();
}
/* ============ nextopt */
static char **argptr; /* argument list for builtin commands */
static char *optionarg; /* set by nextopt (like getopt) */
static char *optptr; /* used by nextopt */
/*
* XXX - should get rid of. Have all builtins use getopt(3).
* The library getopt must have the BSD extension static variable
* "optreset", otherwise it can't be used within the shell safely.
*
* Standard option processing (a la getopt) for builtin routines.
* The only argument that is passed to nextopt is the option string;
* the other arguments are unnecessary. It returns the character,
* or '\0' on end of input.
*/
static int
nextopt(const char *optstring)
{
char *p;
const char *q;
char c;
p = optptr;
if (p == NULL || *p == '\0') {
/* We ate entire "-param", take next one */
p = *argptr;
if (p == NULL)
return '\0';
if (*p != '-')
return '\0';
if (*++p == '\0') /* just "-" ? */
return '\0';
argptr++;
if (LONE_DASH(p)) /* "--" ? */
return '\0';
/* p => next "-param" */
}
/* p => some option char in the middle of a "-param" */
c = *p++;
for (q = optstring; *q != c;) {
if (*q == '\0')
ash_msg_and_raise_error("illegal option -%c", c);
if (*++q == ':')
q++;
}
if (*++q == ':') {
if (*p == '\0') {
p = *argptr++;
if (p == NULL)
ash_msg_and_raise_error("no arg for -%c option", c);
}
optionarg = p;
p = NULL;
}
optptr = p;
return c;
}
/* ============ Shell variables */
/*
* The parsefile structure pointed to by the global variable parsefile
* contains information about the current file being read.
*/
struct shparam {
int nparam; /* # of positional parameters (without $0) */
#if ENABLE_ASH_GETOPTS
int optind; /* next parameter to be processed by getopts */
int optoff; /* used by getopts */
#endif
unsigned char malloced; /* if parameter list dynamically allocated */
char **p; /* parameter list */
};
/*
* Free the list of positional parameters.
*/
static void
freeparam(volatile struct shparam *param)
{
if (param->malloced) {
char **ap, **ap1;
ap = ap1 = param->p;
while (*ap)
free(*ap++);
free(ap1);
}
}
#if ENABLE_ASH_GETOPTS
static void FAST_FUNC getoptsreset(const char *value);
#endif
struct var {
struct var *next; /* next entry in hash list */
int flags; /* flags are defined above */
const char *var_text; /* name=value */
void (*var_func)(const char *) FAST_FUNC; /* function to be called when */
/* the variable gets set/unset */
};
struct localvar {
struct localvar *next; /* next local variable in list */
struct var *vp; /* the variable that was made local */
int flags; /* saved flags */
const char *text; /* saved text */
};
/* flags */
#define VEXPORT 0x01 /* variable is exported */
#define VREADONLY 0x02 /* variable cannot be modified */
#define VSTRFIXED 0x04 /* variable struct is statically allocated */
#define VTEXTFIXED 0x08 /* text is statically allocated */
#define VSTACK 0x10 /* text is allocated on the stack */
#define VUNSET 0x20 /* the variable is not set */
#define VNOFUNC 0x40 /* don't call the callback function */
#define VNOSET 0x80 /* do not set variable - just readonly test */
#define VNOSAVE 0x100 /* when text is on the heap before setvareq */
#if ENABLE_ASH_RANDOM_SUPPORT
# define VDYNAMIC 0x200 /* dynamic variable */
#else
# define VDYNAMIC 0
#endif
/* Need to be before varinit_data[] */
#if ENABLE_LOCALE_SUPPORT
static void FAST_FUNC
change_lc_all(const char *value)
{
if (value && *value != '\0')
setlocale(LC_ALL, value);
}
static void FAST_FUNC
change_lc_ctype(const char *value)
{
if (value && *value != '\0')
setlocale(LC_CTYPE, value);
}
#endif
#if ENABLE_ASH_MAIL
static void chkmail(void);
static void changemail(const char *var_value) FAST_FUNC;
#else
# define chkmail() ((void)0)
#endif
static void changepath(const char *) FAST_FUNC;
#if ENABLE_ASH_RANDOM_SUPPORT
static void change_random(const char *) FAST_FUNC;
#endif
static const struct {
int flags;
const char *var_text;
void (*var_func)(const char *) FAST_FUNC;
} varinit_data[] = {
/*
* Note: VEXPORT would not work correctly here for NOFORK applets:
* some environment strings may be constant.
*/
{ VSTRFIXED|VTEXTFIXED , defifsvar , NULL },
#if ENABLE_ASH_MAIL
{ VSTRFIXED|VTEXTFIXED|VUNSET, "MAIL" , changemail },
{ VSTRFIXED|VTEXTFIXED|VUNSET, "MAILPATH" , changemail },
#endif
{ VSTRFIXED|VTEXTFIXED , bb_PATH_root_path, changepath },
{ VSTRFIXED|VTEXTFIXED , "PS1=$ " , NULL },
{ VSTRFIXED|VTEXTFIXED , "PS2=> " , NULL },
{ VSTRFIXED|VTEXTFIXED , "PS4=+ " , NULL },
#if ENABLE_ASH_GETOPTS
{ VSTRFIXED|VTEXTFIXED , defoptindvar, getoptsreset },
#endif
#if ENABLE_ASH_RANDOM_SUPPORT
{ VSTRFIXED|VTEXTFIXED|VUNSET|VDYNAMIC, "RANDOM", change_random },
#endif
#if ENABLE_LOCALE_SUPPORT
{ VSTRFIXED|VTEXTFIXED|VUNSET, "LC_ALL" , change_lc_all },
{ VSTRFIXED|VTEXTFIXED|VUNSET, "LC_CTYPE" , change_lc_ctype },
#endif
#if ENABLE_FEATURE_EDITING_SAVEHISTORY
{ VSTRFIXED|VTEXTFIXED|VUNSET, "HISTFILE" , NULL },
#endif
};
struct redirtab;
struct globals_var {
struct shparam shellparam; /* $@ current positional parameters */
struct redirtab *redirlist;
int preverrout_fd; /* save fd2 before print debug if xflag is set. */
struct var *vartab[VTABSIZE];
struct var varinit[ARRAY_SIZE(varinit_data)];
};
extern struct globals_var *const ash_ptr_to_globals_var;
#define G_var (*ash_ptr_to_globals_var)
#define shellparam (G_var.shellparam )
//#define redirlist (G_var.redirlist )
#define preverrout_fd (G_var.preverrout_fd)
#define vartab (G_var.vartab )
#define varinit (G_var.varinit )
#define INIT_G_var() do { \
unsigned i; \
(*(struct globals_var**)&ash_ptr_to_globals_var) = xzalloc(sizeof(G_var)); \
barrier(); \
for (i = 0; i < ARRAY_SIZE(varinit_data); i++) { \
varinit[i].flags = varinit_data[i].flags; \
varinit[i].var_text = varinit_data[i].var_text; \
varinit[i].var_func = varinit_data[i].var_func; \
} \
} while (0)
#define vifs varinit[0]
#if ENABLE_ASH_MAIL
# define vmail (&vifs)[1]
# define vmpath (&vmail)[1]
# define vpath (&vmpath)[1]
#else
# define vpath (&vifs)[1]
#endif
#define vps1 (&vpath)[1]
#define vps2 (&vps1)[1]
#define vps4 (&vps2)[1]
#if ENABLE_ASH_GETOPTS
# define voptind (&vps4)[1]
# if ENABLE_ASH_RANDOM_SUPPORT
# define vrandom (&voptind)[1]
# endif
#else
# if ENABLE_ASH_RANDOM_SUPPORT
# define vrandom (&vps4)[1]
# endif
#endif
/*
* The following macros access the values of the above variables.
* They have to skip over the name. They return the null string
* for unset variables.
*/
#define ifsval() (vifs.var_text + 4)
#define ifsset() ((vifs.flags & VUNSET) == 0)
#if ENABLE_ASH_MAIL
# define mailval() (vmail.var_text + 5)
# define mpathval() (vmpath.var_text + 9)
# define mpathset() ((vmpath.flags & VUNSET) == 0)
#endif
#define pathval() (vpath.var_text + 5)
#define ps1val() (vps1.var_text + 4)
#define ps2val() (vps2.var_text + 4)
#define ps4val() (vps4.var_text + 4)
#if ENABLE_ASH_GETOPTS
# define optindval() (voptind.var_text + 7)
#endif
#if ENABLE_ASH_GETOPTS
static void FAST_FUNC
getoptsreset(const char *value)
{
shellparam.optind = number(value) ?: 1;
shellparam.optoff = -1;
}
#endif
/*
* Compares two strings up to the first = or '\0'. The first
* string must be terminated by '='; the second may be terminated by
* either '=' or '\0'.
*/
static int
varcmp(const char *p, const char *q)
{
int c, d;
while ((c = *p) == (d = *q)) {
if (c == '\0' || c == '=')
goto out;
p++;
q++;
}
if (c == '=')
c = '\0';
if (d == '=')
d = '\0';
out:
return c - d;
}
/*
* Find the appropriate entry in the hash table from the name.
*/
static struct var **
hashvar(const char *p)
{
unsigned hashval;
hashval = ((unsigned char) *p) << 4;
while (*p && *p != '=')
hashval += (unsigned char) *p++;
return &vartab[hashval % VTABSIZE];
}
static int
vpcmp(const void *a, const void *b)
{
return varcmp(*(const char **)a, *(const char **)b);
}
/*
* This routine initializes the builtin variables.
*/
static void
initvar(void)
{
struct var *vp;
struct var *end;
struct var **vpp;
/*
* PS1 depends on uid
*/
#if ENABLE_FEATURE_EDITING && ENABLE_FEATURE_EDITING_FANCY_PROMPT
vps1.var_text = "PS1=\\w \\$ ";
#else
if (!geteuid())
vps1.var_text = "PS1=# ";
#endif
vp = varinit;
end = vp + ARRAY_SIZE(varinit);
do {
vpp = hashvar(vp->var_text);
vp->next = *vpp;
*vpp = vp;
} while (++vp < end);
}
static struct var **
findvar(struct var **vpp, const char *name)
{
for (; *vpp; vpp = &(*vpp)->next) {
if (varcmp((*vpp)->var_text, name) == 0) {
break;
}
}
return vpp;
}
/*
* Find the value of a variable. Returns NULL if not set.
*/
static const char* FAST_FUNC
lookupvar(const char *name)
{
struct var *v;
v = *findvar(hashvar(name), name);
if (v) {
#if ENABLE_ASH_RANDOM_SUPPORT
/*
* Dynamic variables are implemented roughly the same way they are
* in bash. Namely, they're "special" so long as they aren't unset.
* As soon as they're unset, they're no longer dynamic, and dynamic
* lookup will no longer happen at that point. -- PFM.
*/
if (v->flags & VDYNAMIC)
v->var_func(NULL);
#endif
if (!(v->flags & VUNSET))
return var_end(v->var_text);
}
return NULL;
}
#if ENABLE_UNICODE_SUPPORT
static void
reinit_unicode_for_ash(void)
{
/* Unicode support should be activated even if LANG is set
* _during_ shell execution, not only if it was set when
* shell was started. Therefore, re-check LANG every time:
*/
if (ENABLE_FEATURE_CHECK_UNICODE_IN_ENV
|| ENABLE_UNICODE_USING_LOCALE
) {
const char *s = lookupvar("LC_ALL");
if (!s) s = lookupvar("LC_CTYPE");
if (!s) s = lookupvar("LANG");
reinit_unicode(s);
}
}
#else
# define reinit_unicode_for_ash() ((void)0)
#endif
/*
* Search the environment of a builtin command.
*/
static const char *
bltinlookup(const char *name)
{
struct strlist *sp;
for (sp = cmdenviron; sp; sp = sp->next) {
if (varcmp(sp->text, name) == 0)
return var_end(sp->text);
}
return lookupvar(name);
}
/*
* Same as setvar except that the variable and value are passed in
* the first argument as name=value. Since the first argument will
* be actually stored in the table, it should not be a string that
* will go away.
* Called with interrupts off.
*/
static void
setvareq(char *s, int flags)
{
struct var *vp, **vpp;
vpp = hashvar(s);
flags |= (VEXPORT & (((unsigned) (1 - aflag)) - 1));
vp = *findvar(vpp, s);
if (vp) {
if ((vp->flags & (VREADONLY|VDYNAMIC)) == VREADONLY) {
const char *n;
if (flags & VNOSAVE)
free(s);
n = vp->var_text;
exitstatus = 1;
ash_msg_and_raise_error("%.*s: is read only", strchrnul(n, '=') - n, n);
}
if (flags & VNOSET)
return;
if (vp->var_func && !(flags & VNOFUNC))
vp->var_func(var_end(s));
if (!(vp->flags & (VTEXTFIXED|VSTACK)))
free((char*)vp->var_text);
flags |= vp->flags & ~(VTEXTFIXED|VSTACK|VNOSAVE|VUNSET);
} else {
/* variable s is not found */
if (flags & VNOSET)
return;
vp = ckzalloc(sizeof(*vp));
vp->next = *vpp;
/*vp->func = NULL; - ckzalloc did it */
*vpp = vp;
}
if (!(flags & (VTEXTFIXED|VSTACK|VNOSAVE)))
s = ckstrdup(s);
vp->var_text = s;
vp->flags = flags;
}
/*
* Set the value of a variable. The flags argument is ored with the
* flags of the variable. If val is NULL, the variable is unset.
*/
static void
setvar(const char *name, const char *val, int flags)
{
const char *q;
char *p;
char *nameeq;
size_t namelen;
size_t vallen;
q = endofname(name);
p = strchrnul(q, '=');
namelen = p - name;
if (!namelen || p != q)
ash_msg_and_raise_error("%.*s: bad variable name", namelen, name);
vallen = 0;
if (val == NULL) {
flags |= VUNSET;
} else {
vallen = strlen(val);
}
INT_OFF;
nameeq = ckmalloc(namelen + vallen + 2);
p = memcpy(nameeq, name, namelen) + namelen;
if (val) {
*p++ = '=';
p = memcpy(p, val, vallen) + vallen;
}
*p = '\0';
setvareq(nameeq, flags | VNOSAVE);
INT_ON;
}
static void FAST_FUNC
setvar0(const char *name, const char *val)
{
setvar(name, val, 0);
}
/*
* Unset the specified variable.
*/
static int
unsetvar(const char *s)
{
struct var **vpp;
struct var *vp;
int retval;
vpp = findvar(hashvar(s), s);
vp = *vpp;
retval = 2;
if (vp) {
int flags = vp->flags;
retval = 1;
if (flags & VREADONLY)
goto out;
#if ENABLE_ASH_RANDOM_SUPPORT
vp->flags &= ~VDYNAMIC;
#endif
if (flags & VUNSET)
goto ok;
if ((flags & VSTRFIXED) == 0) {
INT_OFF;
if ((flags & (VTEXTFIXED|VSTACK)) == 0)
free((char*)vp->var_text);
*vpp = vp->next;
free(vp);
INT_ON;
} else {
setvar0(s, NULL);
vp->flags &= ~VEXPORT;
}
ok:
retval = 0;
}
out:
return retval;
}
/*
* Process a linked list of variable assignments.
*/
static void
listsetvar(struct strlist *list_set_var, int flags)
{
struct strlist *lp = list_set_var;
if (!lp)
return;
INT_OFF;
do {
setvareq(lp->text, flags);
lp = lp->next;
} while (lp);
INT_ON;
}
/*
* Generate a list of variables satisfying the given conditions.
*/
static char **
listvars(int on, int off, char ***end)
{
struct var **vpp;
struct var *vp;
char **ep;
int mask;
STARTSTACKSTR(ep);
vpp = vartab;
mask = on | off;
do {
for (vp = *vpp; vp; vp = vp->next) {
if ((vp->flags & mask) == on) {
if (ep == stackstrend())
ep = growstackstr();
*ep++ = (char*)vp->var_text;
}
}
} while (++vpp < vartab + VTABSIZE);
if (ep == stackstrend())
ep = growstackstr();
if (end)
*end = ep;
*ep++ = NULL;
return grabstackstr(ep);
}
/* ============ Path search helper
*
* The variable path (passed by reference) should be set to the start
* of the path before the first call; path_advance will update
* this value as it proceeds. Successive calls to path_advance will return
* the possible path expansions in sequence. If an option (indicated by
* a percent sign) appears in the path entry then the global variable
* pathopt will be set to point to it; otherwise pathopt will be set to
* NULL.
*/
static const char *pathopt; /* set by path_advance */
static char *
path_advance(const char **path, const char *name)
{
const char *p;
char *q;
const char *start;
size_t len;
if (*path == NULL)
return NULL;
start = *path;
for (p = start; *p && *p != ':' && *p != '%'; p++)
continue;
len = p - start + strlen(name) + 2; /* "2" is for '/' and '\0' */
while (stackblocksize() < len)
growstackblock();
q = stackblock();
if (p != start) {
memcpy(q, start, p - start);
q += p - start;
*q++ = '/';
}
strcpy(q, name);
pathopt = NULL;
if (*p == '%') {
pathopt = ++p;
while (*p && *p != ':')
p++;
}
if (*p == ':')
*path = p + 1;
else
*path = NULL;
return stalloc(len);
}
/* ============ Prompt */
static smallint doprompt; /* if set, prompt the user */
static smallint needprompt; /* true if interactive and at start of line */
#if ENABLE_FEATURE_EDITING
static line_input_t *line_input_state;
static const char *cmdedit_prompt;
static void
putprompt(const char *s)
{
if (ENABLE_ASH_EXPAND_PRMT) {
free((char*)cmdedit_prompt);
cmdedit_prompt = ckstrdup(s);
return;
}
cmdedit_prompt = s;
}
#else
static void
putprompt(const char *s)
{
out2str(s);
}
#endif
#if ENABLE_ASH_EXPAND_PRMT
/* expandstr() needs parsing machinery, so it is far away ahead... */
static const char *expandstr(const char *ps);
#else
#define expandstr(s) s
#endif
static void
setprompt_if(smallint do_set, int whichprompt)
{
const char *prompt;
IF_ASH_EXPAND_PRMT(struct stackmark smark;)
if (!do_set)
return;
needprompt = 0;
switch (whichprompt) {
case 1:
prompt = ps1val();
break;
case 2:
prompt = ps2val();
break;
default: /* 0 */
prompt = nullstr;
}
#if ENABLE_ASH_EXPAND_PRMT
pushstackmark(&smark, stackblocksize());
#endif
putprompt(expandstr(prompt));
#if ENABLE_ASH_EXPAND_PRMT
popstackmark(&smark);
#endif
}
/* ============ The cd and pwd commands */
#define CD_PHYSICAL 1
#define CD_PRINT 2
static int
cdopt(void)
{
int flags = 0;
int i, j;
j = 'L';
while ((i = nextopt("LP")) != '\0') {
if (i != j) {
flags ^= CD_PHYSICAL;
j = i;
}
}
return flags;
}
/*
* Update curdir (the name of the current directory) in response to a
* cd command.
*/
static const char *
updatepwd(const char *dir)
{
char *new;
char *p;
char *cdcomppath;
const char *lim;
cdcomppath = sstrdup(dir);
STARTSTACKSTR(new);
if (*dir != '/') {
if (curdir == nullstr)
return 0;
new = stack_putstr(curdir, new);
}
new = makestrspace(strlen(dir) + 2, new);
lim = (char *)stackblock() + 1;
if (*dir != '/') {
if (new[-1] != '/')
USTPUTC('/', new);
if (new > lim && *lim == '/')
lim++;
} else {
USTPUTC('/', new);
cdcomppath++;
if (dir[1] == '/' && dir[2] != '/') {
USTPUTC('/', new);
cdcomppath++;
lim++;
}
}
p = strtok(cdcomppath, "/");
while (p) {
switch (*p) {
case '.':
if (p[1] == '.' && p[2] == '\0') {
while (new > lim) {
STUNPUTC(new);
if (new[-1] == '/')
break;
}
break;
}
if (p[1] == '\0')
break;
/* fall through */
default:
new = stack_putstr(p, new);
USTPUTC('/', new);
}
p = strtok(NULL, "/");
}
if (new > lim)
STUNPUTC(new);
*new = 0;
return stackblock();
}
/*
* Find out what the current directory is. If we already know the current
* directory, this routine returns immediately.
*/
static char *
getpwd(void)
{
char *dir = getcwd(NULL, 0); /* huh, using glibc extension? */
return dir ? dir : nullstr;
}
static void
setpwd(const char *val, int setold)
{
char *oldcur, *dir;
oldcur = dir = curdir;
if (setold) {
setvar("OLDPWD", oldcur, VEXPORT);
}
INT_OFF;
if (physdir != nullstr) {
if (physdir != oldcur)
free(physdir);
physdir = nullstr;
}
if (oldcur == val || !val) {
char *s = getpwd();
physdir = s;
if (!val)
dir = s;
} else
dir = ckstrdup(val);
if (oldcur != dir && oldcur != nullstr) {
free(oldcur);
}
curdir = dir;
INT_ON;
setvar("PWD", dir, VEXPORT);
}
static void hashcd(void);
/*
* Actually do the chdir. We also call hashcd to let other routines
* know that the current directory has changed.
*/
static int
docd(const char *dest, int flags)
{
const char *dir = NULL;
int err;
TRACE(("docd(\"%s\", %d) called\n", dest, flags));
INT_OFF;
if (!(flags & CD_PHYSICAL)) {
dir = updatepwd(dest);
if (dir)
dest = dir;
}
err = chdir(dest);
if (err)
goto out;
setpwd(dir, 1);
hashcd();
out:
INT_ON;
return err;
}
static int FAST_FUNC
cdcmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
const char *dest;
const char *path;
const char *p;
char c;
struct stat statb;
int flags;
flags = cdopt();
dest = *argptr;
if (!dest)
dest = bltinlookup("HOME");
else if (LONE_DASH(dest)) {
dest = bltinlookup("OLDPWD");
flags |= CD_PRINT;
}
if (!dest)
dest = nullstr;
if (*dest == '/')
goto step6;
if (*dest == '.') {
c = dest[1];
dotdot:
switch (c) {
case '\0':
case '/':
goto step6;
case '.':
c = dest[2];
if (c != '.')
goto dotdot;
}
}
if (!*dest)
dest = ".";
path = bltinlookup("CDPATH");
while (path) {
c = *path;
p = path_advance(&path, dest);
if (stat(p, &statb) >= 0 && S_ISDIR(statb.st_mode)) {
if (c && c != ':')
flags |= CD_PRINT;
docd:
if (!docd(p, flags))
goto out;
goto err;
}
}
step6:
p = dest;
goto docd;
err:
ash_msg_and_raise_error("can't cd to %s", dest);
/* NOTREACHED */
out:
if (flags & CD_PRINT)
out1fmt("%s\n", curdir);
return 0;
}
static int FAST_FUNC
pwdcmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
int flags;
const char *dir = curdir;
flags = cdopt();
if (flags) {
if (physdir == nullstr)
setpwd(dir, 0);
dir = physdir;
}
out1fmt("%s\n", dir);
return 0;
}
/* ============ ... */
#define IBUFSIZ (ENABLE_FEATURE_EDITING ? CONFIG_FEATURE_EDITING_MAX_LEN : 1024)
/* Syntax classes */
#define CWORD 0 /* character is nothing special */
#define CNL 1 /* newline character */
#define CBACK 2 /* a backslash character */
#define CSQUOTE 3 /* single quote */
#define CDQUOTE 4 /* double quote */
#define CENDQUOTE 5 /* a terminating quote */
#define CBQUOTE 6 /* backwards single quote */
#define CVAR 7 /* a dollar sign */
#define CENDVAR 8 /* a '}' character */
#define CLP 9 /* a left paren in arithmetic */
#define CRP 10 /* a right paren in arithmetic */
#define CENDFILE 11 /* end of file */
#define CCTL 12 /* like CWORD, except it must be escaped */
#define CSPCL 13 /* these terminate a word */
#define CIGN 14 /* character should be ignored */
#define PEOF 256
#if ENABLE_ASH_ALIAS
# define PEOA 257
#endif
#define USE_SIT_FUNCTION ENABLE_ASH_OPTIMIZE_FOR_SIZE
#if ENABLE_FEATURE_SH_MATH
# define SIT_ITEM(a,b,c,d) (a | (b << 4) | (c << 8) | (d << 12))
#else
# define SIT_ITEM(a,b,c,d) (a | (b << 4) | (c << 8))
#endif
static const uint16_t S_I_T[] ALIGN2 = {
#if ENABLE_ASH_ALIAS
SIT_ITEM(CSPCL , CIGN , CIGN , CIGN ), /* 0, PEOA */
#endif
SIT_ITEM(CSPCL , CWORD , CWORD, CWORD ), /* 1, ' ' */
SIT_ITEM(CNL , CNL , CNL , CNL ), /* 2, \n */
SIT_ITEM(CWORD , CCTL , CCTL , CWORD ), /* 3, !*-/:=?[]~ */
SIT_ITEM(CDQUOTE , CENDQUOTE, CWORD, CWORD ), /* 4, '"' */
SIT_ITEM(CVAR , CVAR , CWORD, CVAR ), /* 5, $ */
SIT_ITEM(CSQUOTE , CWORD , CENDQUOTE, CWORD), /* 6, "'" */
SIT_ITEM(CSPCL , CWORD , CWORD, CLP ), /* 7, ( */
SIT_ITEM(CSPCL , CWORD , CWORD, CRP ), /* 8, ) */
SIT_ITEM(CBACK , CBACK , CCTL , CBACK ), /* 9, \ */
SIT_ITEM(CBQUOTE , CBQUOTE , CWORD, CBQUOTE), /* 10, ` */
SIT_ITEM(CENDVAR , CENDVAR , CWORD, CENDVAR), /* 11, } */
#if !USE_SIT_FUNCTION
SIT_ITEM(CENDFILE, CENDFILE , CENDFILE, CENDFILE),/* 12, PEOF */
SIT_ITEM(CWORD , CWORD , CWORD, CWORD ), /* 13, 0-9A-Za-z */
SIT_ITEM(CCTL , CCTL , CCTL , CCTL ) /* 14, CTLESC ... */
#endif
#undef SIT_ITEM
};
/* Constants below must match table above */
enum {
#if ENABLE_ASH_ALIAS
CSPCL_CIGN_CIGN_CIGN , /* 0 */
#endif
CSPCL_CWORD_CWORD_CWORD , /* 1 */
CNL_CNL_CNL_CNL , /* 2 */
CWORD_CCTL_CCTL_CWORD , /* 3 */
CDQUOTE_CENDQUOTE_CWORD_CWORD , /* 4 */
CVAR_CVAR_CWORD_CVAR , /* 5 */
CSQUOTE_CWORD_CENDQUOTE_CWORD , /* 6 */
CSPCL_CWORD_CWORD_CLP , /* 7 */
CSPCL_CWORD_CWORD_CRP , /* 8 */
CBACK_CBACK_CCTL_CBACK , /* 9 */
CBQUOTE_CBQUOTE_CWORD_CBQUOTE , /* 10 */
CENDVAR_CENDVAR_CWORD_CENDVAR , /* 11 */
CENDFILE_CENDFILE_CENDFILE_CENDFILE, /* 12 */
CWORD_CWORD_CWORD_CWORD , /* 13 */
CCTL_CCTL_CCTL_CCTL , /* 14 */
};
/* c in SIT(c, syntax) must be an *unsigned char* or PEOA or PEOF,
* caller must ensure proper cast on it if c is *char_ptr!
*/
/* Values for syntax param */
#define BASESYNTAX 0 /* not in quotes */
#define DQSYNTAX 1 /* in double quotes */
#define SQSYNTAX 2 /* in single quotes */
#define ARISYNTAX 3 /* in arithmetic */
#define PSSYNTAX 4 /* prompt. never passed to SIT() */
#if USE_SIT_FUNCTION
static int
SIT(int c, int syntax)
{
/* Used to also have '/' in this string: "\t\n !\"$&'()*-/:;<=>?[\\]`|}~" */
static const char spec_symbls[] ALIGN1 = "\t\n !\"$&'()*-:;<=>?[\\]`|}~";
/*
* This causes '/' to be prepended with CTLESC in dquoted string,
* making "./file"* treated incorrectly because we feed
* ".\/file*" string to glob(), confusing it (see expandmeta func).
* The "homegrown" glob implementation is okay with that,
* but glibc one isn't. With '/' always treated as CWORD,
* both work fine.
*/
# if ENABLE_ASH_ALIAS
static const uint8_t syntax_index_table[] ALIGN1 = {
1, 2, 1, 3, 4, 5, 1, 6, /* "\t\n !\"$&'" */
7, 8, 3, 3,/*3,*/3, 1, 1, /* "()*-/:;<" */
3, 1, 3, 3, 9, 3, 10, 1, /* "=>?[\\]`|" */
11, 3 /* "}~" */
};
# else
static const uint8_t syntax_index_table[] ALIGN1 = {
0, 1, 0, 2, 3, 4, 0, 5, /* "\t\n !\"$&'" */
6, 7, 2, 2,/*2,*/2, 0, 0, /* "()*-/:;<" */
2, 0, 2, 2, 8, 2, 9, 0, /* "=>?[\\]`|" */
10, 2 /* "}~" */
};
# endif
const char *s;
int indx;
if (c == PEOF)
return CENDFILE;
# if ENABLE_ASH_ALIAS
if (c == PEOA)
indx = 0;
else
# endif
{
/* Cast is purely for paranoia here,
* just in case someone passed signed char to us */
if ((unsigned char)c >= CTL_FIRST
&& (unsigned char)c <= CTL_LAST
) {
return CCTL;
}
s = strchrnul(spec_symbls, c);
if (*s == '\0')
return CWORD;
indx = syntax_index_table[s - spec_symbls];
}
return (S_I_T[indx] >> (syntax*4)) & 0xf;
}
#else /* !USE_SIT_FUNCTION */
static const uint8_t syntax_index_table[] ALIGN1 = {
/* BASESYNTAX_DQSYNTAX_SQSYNTAX_ARISYNTAX */
/* 0 */ CWORD_CWORD_CWORD_CWORD,
/* 1 */ CWORD_CWORD_CWORD_CWORD,
/* 2 */ CWORD_CWORD_CWORD_CWORD,
/* 3 */ CWORD_CWORD_CWORD_CWORD,
/* 4 */ CWORD_CWORD_CWORD_CWORD,
/* 5 */ CWORD_CWORD_CWORD_CWORD,
/* 6 */ CWORD_CWORD_CWORD_CWORD,
/* 7 */ CWORD_CWORD_CWORD_CWORD,
/* 8 */ CWORD_CWORD_CWORD_CWORD,
/* 9 "\t" */ CSPCL_CWORD_CWORD_CWORD,
/* 10 "\n" */ CNL_CNL_CNL_CNL,
/* 11 */ CWORD_CWORD_CWORD_CWORD,
/* 12 */ CWORD_CWORD_CWORD_CWORD,
/* 13 */ CWORD_CWORD_CWORD_CWORD,
/* 14 */ CWORD_CWORD_CWORD_CWORD,
/* 15 */ CWORD_CWORD_CWORD_CWORD,
/* 16 */ CWORD_CWORD_CWORD_CWORD,
/* 17 */ CWORD_CWORD_CWORD_CWORD,
/* 18 */ CWORD_CWORD_CWORD_CWORD,
/* 19 */ CWORD_CWORD_CWORD_CWORD,
/* 20 */ CWORD_CWORD_CWORD_CWORD,
/* 21 */ CWORD_CWORD_CWORD_CWORD,
/* 22 */ CWORD_CWORD_CWORD_CWORD,
/* 23 */ CWORD_CWORD_CWORD_CWORD,
/* 24 */ CWORD_CWORD_CWORD_CWORD,
/* 25 */ CWORD_CWORD_CWORD_CWORD,
/* 26 */ CWORD_CWORD_CWORD_CWORD,
/* 27 */ CWORD_CWORD_CWORD_CWORD,
/* 28 */ CWORD_CWORD_CWORD_CWORD,
/* 29 */ CWORD_CWORD_CWORD_CWORD,
/* 30 */ CWORD_CWORD_CWORD_CWORD,
/* 31 */ CWORD_CWORD_CWORD_CWORD,
/* 32 " " */ CSPCL_CWORD_CWORD_CWORD,
/* 33 "!" */ CWORD_CCTL_CCTL_CWORD,
/* 34 """ */ CDQUOTE_CENDQUOTE_CWORD_CWORD,
/* 35 "#" */ CWORD_CWORD_CWORD_CWORD,
/* 36 "$" */ CVAR_CVAR_CWORD_CVAR,
/* 37 "%" */ CWORD_CWORD_CWORD_CWORD,
/* 38 "&" */ CSPCL_CWORD_CWORD_CWORD,
/* 39 "'" */ CSQUOTE_CWORD_CENDQUOTE_CWORD,
/* 40 "(" */ CSPCL_CWORD_CWORD_CLP,
/* 41 ")" */ CSPCL_CWORD_CWORD_CRP,
/* 42 "*" */ CWORD_CCTL_CCTL_CWORD,
/* 43 "+" */ CWORD_CWORD_CWORD_CWORD,
/* 44 "," */ CWORD_CWORD_CWORD_CWORD,
/* 45 "-" */ CWORD_CCTL_CCTL_CWORD,
/* 46 "." */ CWORD_CWORD_CWORD_CWORD,
/* "/" was CWORD_CCTL_CCTL_CWORD, see comment in SIT() function why this is changed: */
/* 47 "/" */ CWORD_CWORD_CWORD_CWORD,
/* 48 "0" */ CWORD_CWORD_CWORD_CWORD,
/* 49 "1" */ CWORD_CWORD_CWORD_CWORD,
/* 50 "2" */ CWORD_CWORD_CWORD_CWORD,
/* 51 "3" */ CWORD_CWORD_CWORD_CWORD,
/* 52 "4" */ CWORD_CWORD_CWORD_CWORD,
/* 53 "5" */ CWORD_CWORD_CWORD_CWORD,
/* 54 "6" */ CWORD_CWORD_CWORD_CWORD,
/* 55 "7" */ CWORD_CWORD_CWORD_CWORD,
/* 56 "8" */ CWORD_CWORD_CWORD_CWORD,
/* 57 "9" */ CWORD_CWORD_CWORD_CWORD,
/* 58 ":" */ CWORD_CCTL_CCTL_CWORD,
/* 59 ";" */ CSPCL_CWORD_CWORD_CWORD,
/* 60 "<" */ CSPCL_CWORD_CWORD_CWORD,
/* 61 "=" */ CWORD_CCTL_CCTL_CWORD,
/* 62 ">" */ CSPCL_CWORD_CWORD_CWORD,
/* 63 "?" */ CWORD_CCTL_CCTL_CWORD,
/* 64 "@" */ CWORD_CWORD_CWORD_CWORD,
/* 65 "A" */ CWORD_CWORD_CWORD_CWORD,
/* 66 "B" */ CWORD_CWORD_CWORD_CWORD,
/* 67 "C" */ CWORD_CWORD_CWORD_CWORD,
/* 68 "D" */ CWORD_CWORD_CWORD_CWORD,
/* 69 "E" */ CWORD_CWORD_CWORD_CWORD,
/* 70 "F" */ CWORD_CWORD_CWORD_CWORD,
/* 71 "G" */ CWORD_CWORD_CWORD_CWORD,
/* 72 "H" */ CWORD_CWORD_CWORD_CWORD,
/* 73 "I" */ CWORD_CWORD_CWORD_CWORD,
/* 74 "J" */ CWORD_CWORD_CWORD_CWORD,
/* 75 "K" */ CWORD_CWORD_CWORD_CWORD,
/* 76 "L" */ CWORD_CWORD_CWORD_CWORD,
/* 77 "M" */ CWORD_CWORD_CWORD_CWORD,
/* 78 "N" */ CWORD_CWORD_CWORD_CWORD,
/* 79 "O" */ CWORD_CWORD_CWORD_CWORD,
/* 80 "P" */ CWORD_CWORD_CWORD_CWORD,
/* 81 "Q" */ CWORD_CWORD_CWORD_CWORD,
/* 82 "R" */ CWORD_CWORD_CWORD_CWORD,
/* 83 "S" */ CWORD_CWORD_CWORD_CWORD,
/* 84 "T" */ CWORD_CWORD_CWORD_CWORD,
/* 85 "U" */ CWORD_CWORD_CWORD_CWORD,
/* 86 "V" */ CWORD_CWORD_CWORD_CWORD,
/* 87 "W" */ CWORD_CWORD_CWORD_CWORD,
/* 88 "X" */ CWORD_CWORD_CWORD_CWORD,
/* 89 "Y" */ CWORD_CWORD_CWORD_CWORD,
/* 90 "Z" */ CWORD_CWORD_CWORD_CWORD,
/* 91 "[" */ CWORD_CCTL_CCTL_CWORD,
/* 92 "\" */ CBACK_CBACK_CCTL_CBACK,
/* 93 "]" */ CWORD_CCTL_CCTL_CWORD,
/* 94 "^" */ CWORD_CWORD_CWORD_CWORD,
/* 95 "_" */ CWORD_CWORD_CWORD_CWORD,
/* 96 "`" */ CBQUOTE_CBQUOTE_CWORD_CBQUOTE,
/* 97 "a" */ CWORD_CWORD_CWORD_CWORD,
/* 98 "b" */ CWORD_CWORD_CWORD_CWORD,
/* 99 "c" */ CWORD_CWORD_CWORD_CWORD,
/* 100 "d" */ CWORD_CWORD_CWORD_CWORD,
/* 101 "e" */ CWORD_CWORD_CWORD_CWORD,
/* 102 "f" */ CWORD_CWORD_CWORD_CWORD,
/* 103 "g" */ CWORD_CWORD_CWORD_CWORD,
/* 104 "h" */ CWORD_CWORD_CWORD_CWORD,
/* 105 "i" */ CWORD_CWORD_CWORD_CWORD,
/* 106 "j" */ CWORD_CWORD_CWORD_CWORD,
/* 107 "k" */ CWORD_CWORD_CWORD_CWORD,
/* 108 "l" */ CWORD_CWORD_CWORD_CWORD,
/* 109 "m" */ CWORD_CWORD_CWORD_CWORD,
/* 110 "n" */ CWORD_CWORD_CWORD_CWORD,
/* 111 "o" */ CWORD_CWORD_CWORD_CWORD,
/* 112 "p" */ CWORD_CWORD_CWORD_CWORD,
/* 113 "q" */ CWORD_CWORD_CWORD_CWORD,
/* 114 "r" */ CWORD_CWORD_CWORD_CWORD,
/* 115 "s" */ CWORD_CWORD_CWORD_CWORD,
/* 116 "t" */ CWORD_CWORD_CWORD_CWORD,
/* 117 "u" */ CWORD_CWORD_CWORD_CWORD,
/* 118 "v" */ CWORD_CWORD_CWORD_CWORD,
/* 119 "w" */ CWORD_CWORD_CWORD_CWORD,
/* 120 "x" */ CWORD_CWORD_CWORD_CWORD,
/* 121 "y" */ CWORD_CWORD_CWORD_CWORD,
/* 122 "z" */ CWORD_CWORD_CWORD_CWORD,
/* 123 "{" */ CWORD_CWORD_CWORD_CWORD,
/* 124 "|" */ CSPCL_CWORD_CWORD_CWORD,
/* 125 "}" */ CENDVAR_CENDVAR_CWORD_CENDVAR,
/* 126 "~" */ CWORD_CCTL_CCTL_CWORD,
/* 127 del */ CWORD_CWORD_CWORD_CWORD,
/* 128 0x80 */ CWORD_CWORD_CWORD_CWORD,
/* 129 CTLESC */ CCTL_CCTL_CCTL_CCTL,
/* 130 CTLVAR */ CCTL_CCTL_CCTL_CCTL,
/* 131 CTLENDVAR */ CCTL_CCTL_CCTL_CCTL,
/* 132 CTLBACKQ */ CCTL_CCTL_CCTL_CCTL,
/* 133 CTLQUOTE */ CCTL_CCTL_CCTL_CCTL,
/* 134 CTLARI */ CCTL_CCTL_CCTL_CCTL,
/* 135 CTLENDARI */ CCTL_CCTL_CCTL_CCTL,
/* 136 CTLQUOTEMARK */ CCTL_CCTL_CCTL_CCTL,
/* 137 */ CWORD_CWORD_CWORD_CWORD,
/* 138 */ CWORD_CWORD_CWORD_CWORD,
/* 139 */ CWORD_CWORD_CWORD_CWORD,
/* 140 */ CWORD_CWORD_CWORD_CWORD,
/* 141 */ CWORD_CWORD_CWORD_CWORD,
/* 142 */ CWORD_CWORD_CWORD_CWORD,
/* 143 */ CWORD_CWORD_CWORD_CWORD,
/* 144 */ CWORD_CWORD_CWORD_CWORD,
/* 145 */ CWORD_CWORD_CWORD_CWORD,
/* 146 */ CWORD_CWORD_CWORD_CWORD,
/* 147 */ CWORD_CWORD_CWORD_CWORD,
/* 148 */ CWORD_CWORD_CWORD_CWORD,
/* 149 */ CWORD_CWORD_CWORD_CWORD,
/* 150 */ CWORD_CWORD_CWORD_CWORD,
/* 151 */ CWORD_CWORD_CWORD_CWORD,
/* 152 */ CWORD_CWORD_CWORD_CWORD,
/* 153 */ CWORD_CWORD_CWORD_CWORD,
/* 154 */ CWORD_CWORD_CWORD_CWORD,
/* 155 */ CWORD_CWORD_CWORD_CWORD,
/* 156 */ CWORD_CWORD_CWORD_CWORD,
/* 157 */ CWORD_CWORD_CWORD_CWORD,
/* 158 */ CWORD_CWORD_CWORD_CWORD,
/* 159 */ CWORD_CWORD_CWORD_CWORD,
/* 160 */ CWORD_CWORD_CWORD_CWORD,
/* 161 */ CWORD_CWORD_CWORD_CWORD,
/* 162 */ CWORD_CWORD_CWORD_CWORD,
/* 163 */ CWORD_CWORD_CWORD_CWORD,
/* 164 */ CWORD_CWORD_CWORD_CWORD,
/* 165 */ CWORD_CWORD_CWORD_CWORD,
/* 166 */ CWORD_CWORD_CWORD_CWORD,
/* 167 */ CWORD_CWORD_CWORD_CWORD,
/* 168 */ CWORD_CWORD_CWORD_CWORD,
/* 169 */ CWORD_CWORD_CWORD_CWORD,
/* 170 */ CWORD_CWORD_CWORD_CWORD,
/* 171 */ CWORD_CWORD_CWORD_CWORD,
/* 172 */ CWORD_CWORD_CWORD_CWORD,
/* 173 */ CWORD_CWORD_CWORD_CWORD,
/* 174 */ CWORD_CWORD_CWORD_CWORD,
/* 175 */ CWORD_CWORD_CWORD_CWORD,
/* 176 */ CWORD_CWORD_CWORD_CWORD,
/* 177 */ CWORD_CWORD_CWORD_CWORD,
/* 178 */ CWORD_CWORD_CWORD_CWORD,
/* 179 */ CWORD_CWORD_CWORD_CWORD,
/* 180 */ CWORD_CWORD_CWORD_CWORD,
/* 181 */ CWORD_CWORD_CWORD_CWORD,
/* 182 */ CWORD_CWORD_CWORD_CWORD,
/* 183 */ CWORD_CWORD_CWORD_CWORD,
/* 184 */ CWORD_CWORD_CWORD_CWORD,
/* 185 */ CWORD_CWORD_CWORD_CWORD,
/* 186 */ CWORD_CWORD_CWORD_CWORD,
/* 187 */ CWORD_CWORD_CWORD_CWORD,
/* 188 */ CWORD_CWORD_CWORD_CWORD,
/* 189 */ CWORD_CWORD_CWORD_CWORD,
/* 190 */ CWORD_CWORD_CWORD_CWORD,
/* 191 */ CWORD_CWORD_CWORD_CWORD,
/* 192 */ CWORD_CWORD_CWORD_CWORD,
/* 193 */ CWORD_CWORD_CWORD_CWORD,
/* 194 */ CWORD_CWORD_CWORD_CWORD,
/* 195 */ CWORD_CWORD_CWORD_CWORD,
/* 196 */ CWORD_CWORD_CWORD_CWORD,
/* 197 */ CWORD_CWORD_CWORD_CWORD,
/* 198 */ CWORD_CWORD_CWORD_CWORD,
/* 199 */ CWORD_CWORD_CWORD_CWORD,
/* 200 */ CWORD_CWORD_CWORD_CWORD,
/* 201 */ CWORD_CWORD_CWORD_CWORD,
/* 202 */ CWORD_CWORD_CWORD_CWORD,
/* 203 */ CWORD_CWORD_CWORD_CWORD,
/* 204 */ CWORD_CWORD_CWORD_CWORD,
/* 205 */ CWORD_CWORD_CWORD_CWORD,
/* 206 */ CWORD_CWORD_CWORD_CWORD,
/* 207 */ CWORD_CWORD_CWORD_CWORD,
/* 208 */ CWORD_CWORD_CWORD_CWORD,
/* 209 */ CWORD_CWORD_CWORD_CWORD,
/* 210 */ CWORD_CWORD_CWORD_CWORD,
/* 211 */ CWORD_CWORD_CWORD_CWORD,
/* 212 */ CWORD_CWORD_CWORD_CWORD,
/* 213 */ CWORD_CWORD_CWORD_CWORD,
/* 214 */ CWORD_CWORD_CWORD_CWORD,
/* 215 */ CWORD_CWORD_CWORD_CWORD,
/* 216 */ CWORD_CWORD_CWORD_CWORD,
/* 217 */ CWORD_CWORD_CWORD_CWORD,
/* 218 */ CWORD_CWORD_CWORD_CWORD,
/* 219 */ CWORD_CWORD_CWORD_CWORD,
/* 220 */ CWORD_CWORD_CWORD_CWORD,
/* 221 */ CWORD_CWORD_CWORD_CWORD,
/* 222 */ CWORD_CWORD_CWORD_CWORD,
/* 223 */ CWORD_CWORD_CWORD_CWORD,
/* 224 */ CWORD_CWORD_CWORD_CWORD,
/* 225 */ CWORD_CWORD_CWORD_CWORD,
/* 226 */ CWORD_CWORD_CWORD_CWORD,
/* 227 */ CWORD_CWORD_CWORD_CWORD,
/* 228 */ CWORD_CWORD_CWORD_CWORD,
/* 229 */ CWORD_CWORD_CWORD_CWORD,
/* 230 */ CWORD_CWORD_CWORD_CWORD,
/* 231 */ CWORD_CWORD_CWORD_CWORD,
/* 232 */ CWORD_CWORD_CWORD_CWORD,
/* 233 */ CWORD_CWORD_CWORD_CWORD,
/* 234 */ CWORD_CWORD_CWORD_CWORD,
/* 235 */ CWORD_CWORD_CWORD_CWORD,
/* 236 */ CWORD_CWORD_CWORD_CWORD,
/* 237 */ CWORD_CWORD_CWORD_CWORD,
/* 238 */ CWORD_CWORD_CWORD_CWORD,
/* 239 */ CWORD_CWORD_CWORD_CWORD,
/* 230 */ CWORD_CWORD_CWORD_CWORD,
/* 241 */ CWORD_CWORD_CWORD_CWORD,
/* 242 */ CWORD_CWORD_CWORD_CWORD,
/* 243 */ CWORD_CWORD_CWORD_CWORD,
/* 244 */ CWORD_CWORD_CWORD_CWORD,
/* 245 */ CWORD_CWORD_CWORD_CWORD,
/* 246 */ CWORD_CWORD_CWORD_CWORD,
/* 247 */ CWORD_CWORD_CWORD_CWORD,
/* 248 */ CWORD_CWORD_CWORD_CWORD,
/* 249 */ CWORD_CWORD_CWORD_CWORD,
/* 250 */ CWORD_CWORD_CWORD_CWORD,
/* 251 */ CWORD_CWORD_CWORD_CWORD,
/* 252 */ CWORD_CWORD_CWORD_CWORD,
/* 253 */ CWORD_CWORD_CWORD_CWORD,
/* 254 */ CWORD_CWORD_CWORD_CWORD,
/* 255 */ CWORD_CWORD_CWORD_CWORD,
/* PEOF */ CENDFILE_CENDFILE_CENDFILE_CENDFILE,
# if ENABLE_ASH_ALIAS
/* PEOA */ CSPCL_CIGN_CIGN_CIGN,
# endif
};
#if 1
# define SIT(c, syntax) ((S_I_T[syntax_index_table[c]] >> ((syntax)*4)) & 0xf)
#else /* debug version, caught one signed char bug */
# define SIT(c, syntax) \
({ \
if ((c) < 0 || (c) > (PEOF + ENABLE_ASH_ALIAS)) \
bb_error_msg_and_die("line:%d c:%d", __LINE__, (c)); \
if ((syntax) < 0 || (syntax) > (2 + ENABLE_FEATURE_SH_MATH)) \
bb_error_msg_and_die("line:%d c:%d", __LINE__, (c)); \
((S_I_T[syntax_index_table[c]] >> ((syntax)*4)) & 0xf); \
})
#endif
#endif /* !USE_SIT_FUNCTION */
/* ============ Alias handling */
#if ENABLE_ASH_ALIAS
#define ALIASINUSE 1
#define ALIASDEAD 2
struct alias {
struct alias *next;
char *name;
char *val;
int flag;
};
static struct alias **atab; // [ATABSIZE];
#define INIT_G_alias() do { \
atab = xzalloc(ATABSIZE * sizeof(atab[0])); \
} while (0)
static struct alias **
__lookupalias(const char *name)
{
unsigned int hashval;
struct alias **app;
const char *p;
unsigned int ch;
p = name;
ch = (unsigned char)*p;
hashval = ch << 4;
while (ch) {
hashval += ch;
ch = (unsigned char)*++p;
}
app = &atab[hashval % ATABSIZE];
for (; *app; app = &(*app)->next) {
if (strcmp(name, (*app)->name) == 0) {
break;
}
}
return app;
}
static struct alias *
lookupalias(const char *name, int check)
{
struct alias *ap = *__lookupalias(name);
if (check && ap && (ap->flag & ALIASINUSE))
return NULL;
return ap;
}
static struct alias *
freealias(struct alias *ap)
{
struct alias *next;
if (ap->flag & ALIASINUSE) {
ap->flag |= ALIASDEAD;
return ap;
}
next = ap->next;
free(ap->name);
free(ap->val);
free(ap);
return next;
}
static void
setalias(const char *name, const char *val)
{
struct alias *ap, **app;
app = __lookupalias(name);
ap = *app;
INT_OFF;
if (ap) {
if (!(ap->flag & ALIASINUSE)) {
free(ap->val);
}
ap->val = ckstrdup(val);
ap->flag &= ~ALIASDEAD;
} else {
/* not found */
ap = ckzalloc(sizeof(struct alias));
ap->name = ckstrdup(name);
ap->val = ckstrdup(val);
/*ap->flag = 0; - ckzalloc did it */
/*ap->next = NULL;*/
*app = ap;
}
INT_ON;
}
static int
unalias(const char *name)
{
struct alias **app;
app = __lookupalias(name);
if (*app) {
INT_OFF;
*app = freealias(*app);
INT_ON;
return 0;
}
return 1;
}
static void
rmaliases(void)
{
struct alias *ap, **app;
int i;
INT_OFF;
for (i = 0; i < ATABSIZE; i++) {
app = &atab[i];
for (ap = *app; ap; ap = *app) {
*app = freealias(*app);
if (ap == *app) {
app = &ap->next;
}
}
}
INT_ON;
}
static void
printalias(const struct alias *ap)
{
out1fmt("%s=%s\n", ap->name, single_quote(ap->val));
}
/*
* TODO - sort output
*/
static int FAST_FUNC
aliascmd(int argc UNUSED_PARAM, char **argv)
{
char *n, *v;
int ret = 0;
struct alias *ap;
if (!argv[1]) {
int i;
for (i = 0; i < ATABSIZE; i++) {
for (ap = atab[i]; ap; ap = ap->next) {
printalias(ap);
}
}
return 0;
}
while ((n = *++argv) != NULL) {
v = strchr(n+1, '=');
if (v == NULL) { /* n+1: funny ksh stuff */
ap = *__lookupalias(n);
if (ap == NULL) {
fprintf(stderr, "%s: %s not found\n", "alias", n);
ret = 1;
} else
printalias(ap);
} else {
*v++ = '\0';
setalias(n, v);
}
}
return ret;
}
static int FAST_FUNC
unaliascmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
int i;
while ((i = nextopt("a")) != '\0') {
if (i == 'a') {
rmaliases();
return 0;
}
}
for (i = 0; *argptr; argptr++) {
if (unalias(*argptr)) {
fprintf(stderr, "%s: %s not found\n", "unalias", *argptr);
i = 1;
}
}
return i;
}
#endif /* ASH_ALIAS */
/* Mode argument to forkshell. Don't change FORK_FG or FORK_BG. */
#define FORK_FG 0
#define FORK_BG 1
#define FORK_NOJOB 2
/* mode flags for showjob(s) */
#define SHOW_ONLY_PGID 0x01 /* show only pgid (jobs -p) */
#define SHOW_PIDS 0x02 /* show individual pids, not just one line per job */
#define SHOW_CHANGED 0x04 /* only jobs whose state has changed */
#define SHOW_STDERR 0x08 /* print to stderr (else stdout) */
/*
* A job structure contains information about a job. A job is either a
* single process or a set of processes contained in a pipeline. In the
* latter case, pidlist will be non-NULL, and will point to a -1 terminated
* array of pids.
*/
struct procstat {
pid_t ps_pid; /* process id */
int ps_status; /* last process status from wait() */
char *ps_cmd; /* text of command being run */
};
struct job {
struct procstat ps0; /* status of process */
struct procstat *ps; /* status or processes when more than one */
#if JOBS
int stopstatus; /* status of a stopped job */
#endif
uint32_t
nprocs: 16, /* number of processes */
state: 8,
#define JOBRUNNING 0 /* at least one proc running */
#define JOBSTOPPED 1 /* all procs are stopped */
#define JOBDONE 2 /* all procs are completed */
#if JOBS
sigint: 1, /* job was killed by SIGINT */
jobctl: 1, /* job running under job control */
#endif
waited: 1, /* true if this entry has been waited for */
used: 1, /* true if this entry is in used */
changed: 1; /* true if status has changed */
struct job *prev_job; /* previous job */
};
static struct job *makejob(/*union node *,*/ int);
static int forkshell(struct job *, union node *, int);
static int waitforjob(struct job *);
#if !JOBS
enum { doing_jobctl = 0 };
#define setjobctl(on) do {} while (0)
#else
static smallint doing_jobctl; //references:8
static void setjobctl(int);
#endif
/*
* Ignore a signal.
*/
static void
ignoresig(int signo)
{
/* Avoid unnecessary system calls. Is it already SIG_IGNed? */
if (sigmode[signo - 1] != S_IGN && sigmode[signo - 1] != S_HARD_IGN) {
/* No, need to do it */
signal(signo, SIG_IGN);
}
sigmode[signo - 1] = S_HARD_IGN;
}
/*
* Only one usage site - in setsignal()
*/
static void
signal_handler(int signo)
{
if (signo == SIGCHLD) {
got_sigchld = 1;
if (!trap[SIGCHLD])
return;
}
gotsig[signo - 1] = 1;
pending_sig = signo;
if (signo == SIGINT && !trap[SIGINT]) {
if (!suppress_int) {
pending_sig = 0;
raise_interrupt(); /* does not return */
}
pending_int = 1;
}
}
/*
* Set the signal handler for the specified signal. The routine figures
* out what it should be set to.
*/
static void
setsignal(int signo)
{
char *t;
char cur_act, new_act;
struct sigaction act;
t = trap[signo];
new_act = S_DFL;
if (t != NULL) { /* trap for this sig is set */
new_act = S_CATCH;
if (t[0] == '\0') /* trap is "": ignore this sig */
new_act = S_IGN;
}
if (rootshell && new_act == S_DFL) {
switch (signo) {
case SIGINT:
if (iflag || minusc || sflag == 0)
new_act = S_CATCH;
break;
case SIGQUIT:
#if DEBUG
if (debug)
break;
#endif
/* man bash:
* "In all cases, bash ignores SIGQUIT. Non-builtin
* commands run by bash have signal handlers
* set to the values inherited by the shell
* from its parent". */
new_act = S_IGN;
break;
case SIGTERM:
if (iflag)
new_act = S_IGN;
break;
#if JOBS
case SIGTSTP:
case SIGTTOU:
if (mflag)
new_act = S_IGN;
break;
#endif
}
}
//TODO: if !rootshell, we reset SIGQUIT to DFL,
//whereas we have to restore it to what shell got on entry
//from the parent. See comment above
if (signo == SIGCHLD)
new_act = S_CATCH;
t = &sigmode[signo - 1];
cur_act = *t;
if (cur_act == 0) {
/* current setting is not yet known */
if (sigaction(signo, NULL, &act)) {
/* pretend it worked; maybe we should give a warning,
* but other shells don't. We don't alter sigmode,
* so we retry every time.
* btw, in Linux it never fails. --vda */
return;
}
if (act.sa_handler == SIG_IGN) {
cur_act = S_HARD_IGN;
if (mflag
&& (signo == SIGTSTP || signo == SIGTTIN || signo == SIGTTOU)
) {
cur_act = S_IGN; /* don't hard ignore these */
}
}
}
if (cur_act == S_HARD_IGN || cur_act == new_act)
return;
act.sa_handler = SIG_DFL;
switch (new_act) {
case S_CATCH:
act.sa_handler = signal_handler;
break;
case S_IGN:
act.sa_handler = SIG_IGN;
break;
}
/* flags and mask matter only if !DFL and !IGN, but we do it
* for all cases for more deterministic behavior:
*/
act.sa_flags = 0;
sigfillset(&act.sa_mask);
sigaction_set(signo, &act);
*t = new_act;
}
/* mode flags for set_curjob */
#define CUR_DELETE 2
#define CUR_RUNNING 1
#define CUR_STOPPED 0
#if JOBS
/* pgrp of shell on invocation */
static int initialpgrp; //references:2
static int ttyfd = -1; //5
#endif
/* array of jobs */
static struct job *jobtab; //5
/* size of array */
static unsigned njobs; //4
/* current job */
static struct job *curjob; //lots
/* number of presumed living untracked jobs */
static int jobless; //4
static void
set_curjob(struct job *jp, unsigned mode)
{
struct job *jp1;
struct job **jpp, **curp;
/* first remove from list */
jpp = curp = &curjob;
while (1) {
jp1 = *jpp;
if (jp1 == jp)
break;
jpp = &jp1->prev_job;
}
*jpp = jp1->prev_job;
/* Then re-insert in correct position */
jpp = curp;
switch (mode) {
default:
#if DEBUG
abort();
#endif
case CUR_DELETE:
/* job being deleted */
break;
case CUR_RUNNING:
/* newly created job or backgrounded job,
* put after all stopped jobs.
*/
while (1) {
jp1 = *jpp;
#if JOBS
if (!jp1 || jp1->state != JOBSTOPPED)
#endif
break;
jpp = &jp1->prev_job;
}
/* FALLTHROUGH */
#if JOBS
case CUR_STOPPED:
#endif
/* newly stopped job - becomes curjob */
jp->prev_job = *jpp;
*jpp = jp;
break;
}
}
#if JOBS || DEBUG
static int
jobno(const struct job *jp)
{
return jp - jobtab + 1;
}
#endif
/*
* Convert a job name to a job structure.
*/
#if !JOBS
#define getjob(name, getctl) getjob(name)
#endif
static struct job *
getjob(const char *name, int getctl)
{
struct job *jp;
struct job *found;
const char *err_msg = "%s: no such job";
unsigned num;
int c;
const char *p;
char *(*match)(const char *, const char *);
jp = curjob;
p = name;
if (!p)
goto currentjob;
if (*p != '%')
goto err;
c = *++p;
if (!c)
goto currentjob;
if (!p[1]) {
if (c == '+' || c == '%') {
currentjob:
err_msg = "No current job";
goto check;
}
if (c == '-') {
if (jp)
jp = jp->prev_job;
err_msg = "No previous job";
check:
if (!jp)
goto err;
goto gotit;
}
}
if (is_number(p)) {
num = atoi(p);
if (num > 0 && num <= njobs) {
jp = jobtab + num - 1;
if (jp->used)
goto gotit;
goto err;
}
}
match = prefix;
if (*p == '?') {
match = strstr;
p++;
}
found = NULL;
while (jp) {
if (match(jp->ps[0].ps_cmd, p)) {
if (found)
goto err;
found = jp;
err_msg = "%s: ambiguous";
}
jp = jp->prev_job;
}
if (!found)
goto err;
jp = found;
gotit:
#if JOBS
err_msg = "job %s not created under job control";
if (getctl && jp->jobctl == 0)
goto err;
#endif
return jp;
err:
ash_msg_and_raise_error(err_msg, name);
}
/*
* Mark a job structure as unused.
*/
static void
freejob(struct job *jp)
{
struct procstat *ps;
int i;
INT_OFF;
for (i = jp->nprocs, ps = jp->ps; --i >= 0; ps++) {
if (ps->ps_cmd != nullstr)
free(ps->ps_cmd);
}
if (jp->ps != &jp->ps0)
free(jp->ps);
jp->used = 0;
set_curjob(jp, CUR_DELETE);
INT_ON;
}
#if JOBS
static void
xtcsetpgrp(int fd, pid_t pgrp)
{
if (tcsetpgrp(fd, pgrp))
ash_msg_and_raise_error("can't set tty process group (%m)");
}
/*
* Turn job control on and off.
*
* Note: This code assumes that the third arg to ioctl is a character
* pointer, which is true on Berkeley systems but not System V. Since
* System V doesn't have job control yet, this isn't a problem now.
*
* Called with interrupts off.
*/
static void
setjobctl(int on)
{
int fd;
int pgrp;
if (on == doing_jobctl || rootshell == 0)
return;
if (on) {
int ofd;
ofd = fd = open(_PATH_TTY, O_RDWR);
if (fd < 0) {
/* BTW, bash will try to open(ttyname(0)) if open("/dev/tty") fails.
* That sometimes helps to acquire controlling tty.
* Obviously, a workaround for bugs when someone
* failed to provide a controlling tty to bash! :) */
fd = 2;
while (!isatty(fd))
if (--fd < 0)
goto out;
}
/* fd is a tty at this point */
fd = fcntl(fd, F_DUPFD, 10);
if (ofd >= 0) /* if it is "/dev/tty", close. If 0/1/2, dont */
close(ofd);
if (fd < 0)
goto out; /* F_DUPFD failed */
close_on_exec_on(fd);
while (1) { /* while we are in the background */
pgrp = tcgetpgrp(fd);
if (pgrp < 0) {
out:
ash_msg("can't access tty; job control turned off");
mflag = on = 0;
goto close;
}
if (pgrp == getpgrp())
break;
killpg(0, SIGTTIN);
}
initialpgrp = pgrp;
setsignal(SIGTSTP);
setsignal(SIGTTOU);
setsignal(SIGTTIN);
pgrp = rootpid;
setpgid(0, pgrp);
xtcsetpgrp(fd, pgrp);
} else {
/* turning job control off */
fd = ttyfd;
pgrp = initialpgrp;
/* was xtcsetpgrp, but this can make exiting ash
* loop forever if pty is already deleted */
tcsetpgrp(fd, pgrp);
setpgid(0, pgrp);
setsignal(SIGTSTP);
setsignal(SIGTTOU);
setsignal(SIGTTIN);
close:
if (fd >= 0)
close(fd);
fd = -1;
}
ttyfd = fd;
doing_jobctl = on;
}
static int FAST_FUNC
killcmd(int argc, char **argv)
{
if (argv[1] && strcmp(argv[1], "-l") != 0) {
int i = 1;
do {
if (argv[i][0] == '%') {
/*
* "kill %N" - job kill
* Converting to pgrp / pid kill
*/
struct job *jp;
char *dst;
int j, n;
jp = getjob(argv[i], 0);
/*
* In jobs started under job control, we signal
* entire process group by kill -PGRP_ID.
* This happens, f.e., in interactive shell.
*
* Otherwise, we signal each child via
* kill PID1 PID2 PID3.
* Testcases:
* sh -c 'sleep 1|sleep 1 & kill %1'
* sh -c 'true|sleep 2 & sleep 1; kill %1'
* sh -c 'true|sleep 1 & sleep 2; kill %1'
*/
n = jp->nprocs; /* can't be 0 (I hope) */
if (jp->jobctl)
n = 1;
dst = alloca(n * sizeof(int)*4);
argv[i] = dst;
for (j = 0; j < n; j++) {
struct procstat *ps = &jp->ps[j];
/* Skip non-running and not-stopped members
* (i.e. dead members) of the job
*/
if (ps->ps_status != -1 && !WIFSTOPPED(ps->ps_status))
continue;
/*
* kill_main has matching code to expect
* leading space. Needed to not confuse
* negative pids with "kill -SIGNAL_NO" syntax
*/
dst += sprintf(dst, jp->jobctl ? " -%u" : " %u", (int)ps->ps_pid);
}
*dst = '\0';
}
} while (argv[++i]);
}
return kill_main(argc, argv);
}
static void
showpipe(struct job *jp /*, FILE *out*/)
{
struct procstat *ps;
struct procstat *psend;
psend = jp->ps + jp->nprocs;
for (ps = jp->ps + 1; ps < psend; ps++)
printf(" | %s", ps->ps_cmd);
newline_and_flush(stdout);
flush_stdout_stderr();
}
static int
restartjob(struct job *jp, int mode)
{
struct procstat *ps;
int i;
int status;
pid_t pgid;
INT_OFF;
if (jp->state == JOBDONE)
goto out;
jp->state = JOBRUNNING;
pgid = jp->ps[0].ps_pid;
if (mode == FORK_FG)
xtcsetpgrp(ttyfd, pgid);
killpg(pgid, SIGCONT);
ps = jp->ps;
i = jp->nprocs;
do {
if (WIFSTOPPED(ps->ps_status)) {
ps->ps_status = -1;
}
ps++;
} while (--i);
out:
status = (mode == FORK_FG) ? waitforjob(jp) : 0;
INT_ON;
return status;
}
static int FAST_FUNC
fg_bgcmd(int argc UNUSED_PARAM, char **argv)
{
struct job *jp;
int mode;
int retval;
mode = (**argv == 'f') ? FORK_FG : FORK_BG;
nextopt(nullstr);
argv = argptr;
do {
jp = getjob(*argv, 1);
if (mode == FORK_BG) {
set_curjob(jp, CUR_RUNNING);
printf("[%d] ", jobno(jp));
}
out1str(jp->ps[0].ps_cmd);
showpipe(jp /*, stdout*/);
retval = restartjob(jp, mode);
} while (*argv && *++argv);
return retval;
}
#endif
static int
sprint_status48(char *s, int status, int sigonly)
{
int col;
int st;
col = 0;
if (!WIFEXITED(status)) {
if (JOBS && WIFSTOPPED(status))
st = WSTOPSIG(status);
else
st = WTERMSIG(status);
if (sigonly) {
if (st == SIGINT || st == SIGPIPE)
goto out;
if (JOBS && WIFSTOPPED(status))
goto out;
}
st &= 0x7f;
//TODO: use bbox's get_signame? strsignal adds ~600 bytes to text+rodata
col = fmtstr(s, 32, strsignal(st));
if (WCOREDUMP(status)) {
strcpy(s + col, " (core dumped)");
col += sizeof(" (core dumped)")-1;
}
} else if (!sigonly) {
st = WEXITSTATUS(status);
col = fmtstr(s, 16, (st ? "Done(%d)" : "Done"), st);
}
out:
return col;
}
static int
wait_block_or_sig(int *status)
{
int pid;
do {
sigset_t mask;
/* Poll all children for changes in their state */
got_sigchld = 0;
/* if job control is active, accept stopped processes too */
pid = waitpid(-1, status, doing_jobctl ? (WNOHANG|WUNTRACED) : WNOHANG);
if (pid != 0)
break; /* Error (e.g. EINTR, ECHILD) or pid */
/* Children exist, but none are ready. Sleep until interesting signal */
#if 1
sigfillset(&mask);
sigprocmask(SIG_SETMASK, &mask, &mask);
while (!got_sigchld && !pending_sig)
sigsuspend(&mask);
sigprocmask(SIG_SETMASK, &mask, NULL);
#else /* unsafe: a signal can set pending_sig after check, but before pause() */
while (!got_sigchld && !pending_sig)
pause();
#endif
/* If it was SIGCHLD, poll children again */
} while (got_sigchld);
return pid;
}
#define DOWAIT_NONBLOCK 0
#define DOWAIT_BLOCK 1
#define DOWAIT_BLOCK_OR_SIG 2
static int
dowait(int block, struct job *job)
{
int pid;
int status;
struct job *jp;
struct job *thisjob = NULL;
TRACE(("dowait(0x%x) called\n", block));
/* It's wrong to call waitpid() outside of INT_OFF region:
* signal can arrive just after syscall return and handler can
* longjmp away, losing stop/exit notification processing.
* Thus, for "jobs" builtin, and for waiting for a fg job,
* we call waitpid() (blocking or non-blocking) inside INT_OFF.
*
* However, for "wait" builtin it is wrong to simply call waitpid()
* in INT_OFF region: "wait" needs to wait for any running job
* to change state, but should exit on any trap too.
* In INT_OFF region, a signal just before syscall entry can set
* pending_sig variables, but we can't check them, and we would
* either enter a sleeping waitpid() (BUG), or need to busy-loop.
*
* Because of this, we run inside INT_OFF, but use a special routine
* which combines waitpid() and sigsuspend().
* This is the reason why we need to have a handler for SIGCHLD:
* SIG_DFL handler does not wake sigsuspend().
*/
INT_OFF;
if (block == DOWAIT_BLOCK_OR_SIG) {
pid = wait_block_or_sig(&status);
} else {
int wait_flags = 0;
if (block == DOWAIT_NONBLOCK)
wait_flags = WNOHANG;
/* if job control is active, accept stopped processes too */
if (doing_jobctl)
wait_flags |= WUNTRACED;
/* NB: _not_ safe_waitpid, we need to detect EINTR */
pid = waitpid(-1, &status, wait_flags);
}
TRACE(("wait returns pid=%d, status=0x%x, errno=%d(%s)\n",
pid, status, errno, strerror(errno)));
if (pid <= 0)
goto out;
thisjob = NULL;
for (jp = curjob; jp; jp = jp->prev_job) {
int jobstate;
struct procstat *ps;
struct procstat *psend;
if (jp->state == JOBDONE)
continue;
jobstate = JOBDONE;
ps = jp->ps;
psend = ps + jp->nprocs;
do {
if (ps->ps_pid == pid) {
TRACE(("Job %d: changing status of proc %d "
"from 0x%x to 0x%x\n",
jobno(jp), pid, ps->ps_status, status));
ps->ps_status = status;
thisjob = jp;
}
if (ps->ps_status == -1)
jobstate = JOBRUNNING;
#if JOBS
if (jobstate == JOBRUNNING)
continue;
if (WIFSTOPPED(ps->ps_status)) {
jp->stopstatus = ps->ps_status;
jobstate = JOBSTOPPED;
}
#endif
} while (++ps < psend);
if (!thisjob)
continue;
/* Found the job where one of its processes changed its state.
* Is there at least one live and running process in this job? */
if (jobstate != JOBRUNNING) {
/* No. All live processes in the job are stopped
* (JOBSTOPPED) or there are no live processes (JOBDONE)
*/
thisjob->changed = 1;
if (thisjob->state != jobstate) {
TRACE(("Job %d: changing state from %d to %d\n",
jobno(thisjob), thisjob->state, jobstate));
thisjob->state = jobstate;
#if JOBS
if (jobstate == JOBSTOPPED)
set_curjob(thisjob, CUR_STOPPED);
#endif
}
}
goto out;
}
/* The process wasn't found in job list */
if (JOBS && !WIFSTOPPED(status))
jobless--;
out:
INT_ON;
if (thisjob && thisjob == job) {
char s[48 + 1];
int len;
len = sprint_status48(s, status, 1);
if (len) {
s[len] = '\n';
s[len + 1] = '\0';
out2str(s);
}
}
return pid;
}
#if JOBS
static void
showjob(struct job *jp, int mode)
{
struct procstat *ps;
struct procstat *psend;
int col;
int indent_col;
char s[16 + 16 + 48];
FILE *out = (mode & SHOW_STDERR ? stderr : stdout);
ps = jp->ps;
if (mode & SHOW_ONLY_PGID) { /* jobs -p */
/* just output process (group) id of pipeline */
fprintf(out, "%d\n", ps->ps_pid);
return;
}
col = fmtstr(s, 16, "[%d] ", jobno(jp));
indent_col = col;
if (jp == curjob)
s[col - 3] = '+';
else if (curjob && jp == curjob->prev_job)
s[col - 3] = '-';
if (mode & SHOW_PIDS)
col += fmtstr(s + col, 16, "%d ", ps->ps_pid);
psend = ps + jp->nprocs;
if (jp->state == JOBRUNNING) {
strcpy(s + col, "Running");
col += sizeof("Running") - 1;
} else {
int status = psend[-1].ps_status;
if (jp->state == JOBSTOPPED)
status = jp->stopstatus;
col += sprint_status48(s + col, status, 0);
}
/* By now, "[JOBID]* [maybe PID] STATUS" is printed */
/* This loop either prints "<cmd1> | <cmd2> | <cmd3>" line
* or prints several "PID | <cmdN>" lines,
* depending on SHOW_PIDS bit.
* We do not print status of individual processes
* between PID and <cmdN>. bash does it, but not very well:
* first line shows overall job status, not process status,
* making it impossible to know 1st process status.
*/
goto start;
do {
/* for each process */
s[0] = '\0';
col = 33;
if (mode & SHOW_PIDS)
col = fmtstr(s, 48, "\n%*c%d ", indent_col, ' ', ps->ps_pid) - 1;
start:
fprintf(out, "%s%*c%s%s",
s,
33 - col >= 0 ? 33 - col : 0, ' ',
ps == jp->ps ? "" : "| ",
ps->ps_cmd
);
} while (++ps != psend);
newline_and_flush(out);
jp->changed = 0;
if (jp->state == JOBDONE) {
TRACE(("showjob: freeing job %d\n", jobno(jp)));
freejob(jp);
}
}
/*
* Print a list of jobs. If "change" is nonzero, only print jobs whose
* statuses have changed since the last call to showjobs.
*/
static void
showjobs(int mode)
{
struct job *jp;
TRACE(("showjobs(0x%x) called\n", mode));
/* Handle all finished jobs */
while (dowait(DOWAIT_NONBLOCK, NULL) > 0)
continue;
for (jp = curjob; jp; jp = jp->prev_job) {
if (!(mode & SHOW_CHANGED) || jp->changed) {
showjob(jp, mode);
}
}
}
static int FAST_FUNC
jobscmd(int argc UNUSED_PARAM, char **argv)
{
int mode, m;
mode = 0;
while ((m = nextopt("lp")) != '\0') {
if (m == 'l')
mode |= SHOW_PIDS;
else
mode |= SHOW_ONLY_PGID;
}
argv = argptr;
if (*argv) {
do
showjob(getjob(*argv, 0), mode);
while (*++argv);
} else {
showjobs(mode);
}
return 0;
}
#endif /* JOBS */
/* Called only on finished or stopped jobs (no members are running) */
static int
getstatus(struct job *job)
{
int status;
int retval;
struct procstat *ps;
/* Fetch last member's status */
ps = job->ps + job->nprocs - 1;
status = ps->ps_status;
if (pipefail) {
/* "set -o pipefail" mode: use last _nonzero_ status */
while (status == 0 && --ps >= job->ps)
status = ps->ps_status;
}
retval = WEXITSTATUS(status);
if (!WIFEXITED(status)) {
#if JOBS
retval = WSTOPSIG(status);
if (!WIFSTOPPED(status))
#endif
{
/* XXX: limits number of signals */
retval = WTERMSIG(status);
#if JOBS
if (retval == SIGINT)
job->sigint = 1;
#endif
}
retval += 128;
}
TRACE(("getstatus: job %d, nproc %d, status 0x%x, retval 0x%x\n",
jobno(job), job->nprocs, status, retval));
return retval;
}
static int FAST_FUNC
waitcmd(int argc UNUSED_PARAM, char **argv)
{
struct job *job;
int retval;
struct job *jp;
nextopt(nullstr);
retval = 0;
argv = argptr;
if (!*argv) {
/* wait for all jobs */
for (;;) {
jp = curjob;
while (1) {
if (!jp) /* no running procs */
goto ret;
if (jp->state == JOBRUNNING)
break;
jp->waited = 1;
jp = jp->prev_job;
}
/* man bash:
* "When bash is waiting for an asynchronous command via
* the wait builtin, the reception of a signal for which a trap
* has been set will cause the wait builtin to return immediately
* with an exit status greater than 128, immediately after which
* the trap is executed."
*/
dowait(DOWAIT_BLOCK_OR_SIG, NULL);
/* if child sends us a signal *and immediately exits*,
* dowait() returns pid > 0. Check this case,
* not "if (dowait() < 0)"!
*/
if (pending_sig)
goto sigout;
}
}
retval = 127;
do {
if (**argv != '%') {
pid_t pid = number(*argv);
job = curjob;
while (1) {
if (!job)
goto repeat;
if (job->ps[job->nprocs - 1].ps_pid == pid)
break;
job = job->prev_job;
}
} else {
job = getjob(*argv, 0);
}
/* loop until process terminated or stopped */
while (job->state == JOBRUNNING) {
dowait(DOWAIT_BLOCK_OR_SIG, NULL);
if (pending_sig)
goto sigout;
}
job->waited = 1;
retval = getstatus(job);
repeat: ;
} while (*++argv);
ret:
return retval;
sigout:
retval = 128 + pending_sig;
return retval;
}
static struct job *
growjobtab(void)
{
size_t len;
ptrdiff_t offset;
struct job *jp, *jq;
len = njobs * sizeof(*jp);
jq = jobtab;
jp = ckrealloc(jq, len + 4 * sizeof(*jp));
offset = (char *)jp - (char *)jq;
if (offset) {
/* Relocate pointers */
size_t l = len;
jq = (struct job *)((char *)jq + l);
while (l) {
l -= sizeof(*jp);
jq--;
#define joff(p) ((struct job *)((char *)(p) + l))
#define jmove(p) (p) = (void *)((char *)(p) + offset)
if (joff(jp)->ps == &jq->ps0)
jmove(joff(jp)->ps);
if (joff(jp)->prev_job)
jmove(joff(jp)->prev_job);
}
if (curjob)
jmove(curjob);
#undef joff
#undef jmove
}
njobs += 4;
jobtab = jp;
jp = (struct job *)((char *)jp + len);
jq = jp + 3;
do {
jq->used = 0;
} while (--jq >= jp);
return jp;
}
/*
* Return a new job structure.
* Called with interrupts off.
*/
static struct job *
makejob(/*union node *node,*/ int nprocs)
{
int i;
struct job *jp;
for (i = njobs, jp = jobtab; ; jp++) {
if (--i < 0) {
jp = growjobtab();
break;
}
if (jp->used == 0)
break;
if (jp->state != JOBDONE || !jp->waited)
continue;
#if JOBS
if (doing_jobctl)
continue;
#endif
freejob(jp);
break;
}
memset(jp, 0, sizeof(*jp));
#if JOBS
/* jp->jobctl is a bitfield.
* "jp->jobctl |= jobctl" likely to give awful code */
if (doing_jobctl)
jp->jobctl = 1;
#endif
jp->prev_job = curjob;
curjob = jp;
jp->used = 1;
jp->ps = &jp->ps0;
if (nprocs > 1) {
jp->ps = ckmalloc(nprocs * sizeof(struct procstat));
}
TRACE(("makejob(%d) returns %%%d\n", nprocs,
jobno(jp)));
return jp;
}
#if JOBS
/*
* Return a string identifying a command (to be printed by the
* jobs command).
*/
static char *cmdnextc;
static void
cmdputs(const char *s)
{
static const char vstype[VSTYPE + 1][3] = {
"", "}", "-", "+", "?", "=",
"%", "%%", "#", "##"
IF_ASH_BASH_COMPAT(, ":", "/", "//")
};
const char *p, *str;
char cc[2];
char *nextc;
unsigned char c;
unsigned char subtype = 0;
int quoted = 0;
cc[1] = '\0';
nextc = makestrspace((strlen(s) + 1) * 8, cmdnextc);
p = s;
while ((c = *p++) != '\0') {
str = NULL;
switch (c) {
case CTLESC:
c = *p++;
break;
case CTLVAR:
subtype = *p++;
if ((subtype & VSTYPE) == VSLENGTH)
str = "${#";
else
str = "${";
goto dostr;
case CTLENDVAR:
str = "\"}" + !(quoted & 1);
quoted >>= 1;
subtype = 0;
goto dostr;
case CTLBACKQ:
str = "$(...)";
goto dostr;
#if ENABLE_FEATURE_SH_MATH
case CTLARI:
str = "$((";
goto dostr;
case CTLENDARI:
str = "))";
goto dostr;
#endif
case CTLQUOTEMARK:
quoted ^= 1;
c = '"';
break;
case '=':
if (subtype == 0)
break;
if ((subtype & VSTYPE) != VSNORMAL)
quoted <<= 1;
str = vstype[subtype & VSTYPE];
if (subtype & VSNUL)
c = ':';
else
goto checkstr;
break;
case '\'':
case '\\':
case '"':
case '$':
/* These can only happen inside quotes */
cc[0] = c;
str = cc;
c = '\\';
break;
default:
break;
}
USTPUTC(c, nextc);
checkstr:
if (!str)
continue;
dostr:
while ((c = *str++) != '\0') {
USTPUTC(c, nextc);
}
} /* while *p++ not NUL */
if (quoted & 1) {
USTPUTC('"', nextc);
}
*nextc = 0;
cmdnextc = nextc;
}
/* cmdtxt() and cmdlist() call each other */
static void cmdtxt(union node *n);
static void
cmdlist(union node *np, int sep)
{
for (; np; np = np->narg.next) {
if (!sep)
cmdputs(" ");
cmdtxt(np);
if (sep && np->narg.next)
cmdputs(" ");
}
}
static void
cmdtxt(union node *n)
{
union node *np;
struct nodelist *lp;
const char *p;
if (!n)
return;
switch (n->type) {
default:
#if DEBUG
abort();
#endif
case NPIPE:
lp = n->npipe.cmdlist;
for (;;) {
cmdtxt(lp->n);
lp = lp->next;
if (!lp)
break;
cmdputs(" | ");
}
break;
case NSEMI:
p = "; ";
goto binop;
case NAND:
p = " && ";
goto binop;
case NOR:
p = " || ";
binop:
cmdtxt(n->nbinary.ch1);
cmdputs(p);
n = n->nbinary.ch2;
goto donode;
case NREDIR:
case NBACKGND:
n = n->nredir.n;
goto donode;
case NNOT:
cmdputs("!");
n = n->nnot.com;
donode:
cmdtxt(n);
break;
case NIF:
cmdputs("if ");
cmdtxt(n->nif.test);
cmdputs("; then ");
if (n->nif.elsepart) {
cmdtxt(n->nif.ifpart);
cmdputs("; else ");
n = n->nif.elsepart;
} else {
n = n->nif.ifpart;
}
p = "; fi";
goto dotail;
case NSUBSHELL:
cmdputs("(");
n = n->nredir.n;
p = ")";
goto dotail;
case NWHILE:
p = "while ";
goto until;
case NUNTIL:
p = "until ";
until:
cmdputs(p);
cmdtxt(n->nbinary.ch1);
n = n->nbinary.ch2;
p = "; done";
dodo:
cmdputs("; do ");
dotail:
cmdtxt(n);
goto dotail2;
case NFOR:
cmdputs("for ");
cmdputs(n->nfor.var);
cmdputs(" in ");
cmdlist(n->nfor.args, 1);
n = n->nfor.body;
p = "; done";
goto dodo;
case NDEFUN:
cmdputs(n->narg.text);
p = "() { ... }";
goto dotail2;
case NCMD:
cmdlist(n->ncmd.args, 1);
cmdlist(n->ncmd.redirect, 0);
break;
case NARG:
p = n->narg.text;
dotail2:
cmdputs(p);
break;
case NHERE:
case NXHERE:
p = "<<...";
goto dotail2;
case NCASE:
cmdputs("case ");
cmdputs(n->ncase.expr->narg.text);
cmdputs(" in ");
for (np = n->ncase.cases; np; np = np->nclist.next) {
cmdtxt(np->nclist.pattern);
cmdputs(") ");
cmdtxt(np->nclist.body);
cmdputs(";; ");
}
p = "esac";
goto dotail2;
case NTO:
p = ">";
goto redir;
case NCLOBBER:
p = ">|";
goto redir;
case NAPPEND:
p = ">>";
goto redir;
#if ENABLE_ASH_BASH_COMPAT
case NTO2:
#endif
case NTOFD:
p = ">&";
goto redir;
case NFROM:
p = "<";
goto redir;
case NFROMFD:
p = "<&";
goto redir;
case NFROMTO:
p = "<>";
redir:
cmdputs(utoa(n->nfile.fd));
cmdputs(p);
if (n->type == NTOFD || n->type == NFROMFD) {
cmdputs(utoa(n->ndup.dupfd));
break;
}
n = n->nfile.fname;
goto donode;
}
}
static char *
commandtext(union node *n)
{
char *name;
STARTSTACKSTR(cmdnextc);
cmdtxt(n);
name = stackblock();
TRACE(("commandtext: name %p, end %p\n", name, cmdnextc));
return ckstrdup(name);
}
#endif /* JOBS */
/*
* Fork off a subshell. If we are doing job control, give the subshell its
* own process group. Jp is a job structure that the job is to be added to.
* N is the command that will be evaluated by the child. Both jp and n may
* be NULL. The mode parameter can be one of the following:
* FORK_FG - Fork off a foreground process.
* FORK_BG - Fork off a background process.
* FORK_NOJOB - Like FORK_FG, but don't give the process its own
* process group even if job control is on.
*
* When job control is turned off, background processes have their standard
* input redirected to /dev/null (except for the second and later processes
* in a pipeline).
*
* Called with interrupts off.
*/
/*
* Clear traps on a fork.
*/
static void
clear_traps(void)
{
char **tp;
INT_OFF;
for (tp = trap; tp < &trap[NSIG]; tp++) {
if (*tp && **tp) { /* trap not NULL or "" (SIG_IGN) */
if (trap_ptr == trap)
free(*tp);
/* else: it "belongs" to trap_ptr vector, don't free */
*tp = NULL;
if ((tp - trap) != 0)
setsignal(tp - trap);
}
}
may_have_traps = 0;
INT_ON;
}
/* Lives far away from here, needed for forkchild */
static void closescript(void);
/* Called after fork(), in child */
/* jp and n are NULL when called by openhere() for heredoc support */
static NOINLINE void
forkchild(struct job *jp, union node *n, int mode)
{
int oldlvl;
TRACE(("Child shell %d\n", getpid()));
oldlvl = shlvl;
shlvl++;
/* man bash: "Non-builtin commands run by bash have signal handlers
* set to the values inherited by the shell from its parent".
* Do we do it correctly? */
closescript();
if (mode == FORK_NOJOB /* is it `xxx` ? */
&& n && n->type == NCMD /* is it single cmd? */
/* && n->ncmd.args->type == NARG - always true? */
&& n->ncmd.args && strcmp(n->ncmd.args->narg.text, "trap") == 0
&& n->ncmd.args->narg.next == NULL /* "trap" with no arguments */
/* && n->ncmd.args->narg.backquote == NULL - do we need to check this? */
) {
TRACE(("Trap hack\n"));
/* Awful hack for `trap` or $(trap).
*
* http://www.opengroup.org/onlinepubs/009695399/utilities/trap.html
* contains an example where "trap" is executed in a subshell:
*
* save_traps=$(trap)
* ...
* eval "$save_traps"
*
* Standard does not say that "trap" in subshell shall print
* parent shell's traps. It only says that its output
* must have suitable form, but then, in the above example
* (which is not supposed to be normative), it implies that.
*
* bash (and probably other shell) does implement it
* (traps are reset to defaults, but "trap" still shows them),
* but as a result, "trap" logic is hopelessly messed up:
*
* # trap
* trap -- 'echo Ho' SIGWINCH <--- we have a handler
* # (trap) <--- trap is in subshell - no output (correct, traps are reset)
* # true | trap <--- trap is in subshell - no output (ditto)
* # echo `true | trap` <--- in subshell - output (but traps are reset!)
* trap -- 'echo Ho' SIGWINCH
* # echo `(trap)` <--- in subshell in subshell - output
* trap -- 'echo Ho' SIGWINCH
* # echo `true | (trap)` <--- in subshell in subshell in subshell - output!
* trap -- 'echo Ho' SIGWINCH
*
* The rules when to forget and when to not forget traps
* get really complex and nonsensical.
*
* Our solution: ONLY bare $(trap) or `trap` is special.
*/
/* Save trap handler strings for trap builtin to print */
trap_ptr = xmemdup(trap, sizeof(trap));
/* Fall through into clearing traps */
}
clear_traps();
#if JOBS
/* do job control only in root shell */
doing_jobctl = 0;
if (mode != FORK_NOJOB && jp->jobctl && oldlvl == 0) {
pid_t pgrp;
if (jp->nprocs == 0)
pgrp = getpid();
else
pgrp = jp->ps[0].ps_pid;
/* this can fail because we are doing it in the parent also */
setpgid(0, pgrp);
if (mode == FORK_FG)
xtcsetpgrp(ttyfd, pgrp);
setsignal(SIGTSTP);
setsignal(SIGTTOU);
} else
#endif
if (mode == FORK_BG) {
/* man bash: "When job control is not in effect,
* asynchronous commands ignore SIGINT and SIGQUIT" */
ignoresig(SIGINT);
ignoresig(SIGQUIT);
if (jp->nprocs == 0) {
close(0);
if (open(bb_dev_null, O_RDONLY) != 0)
ash_msg_and_raise_error("can't open '%s'", bb_dev_null);
}
}
if (oldlvl == 0) {
if (iflag) { /* why if iflag only? */
setsignal(SIGINT);
setsignal(SIGTERM);
}
/* man bash:
* "In all cases, bash ignores SIGQUIT. Non-builtin
* commands run by bash have signal handlers
* set to the values inherited by the shell
* from its parent".
* Take care of the second rule: */
setsignal(SIGQUIT);
}
#if JOBS
if (n && n->type == NCMD
&& n->ncmd.args && strcmp(n->ncmd.args->narg.text, "jobs") == 0
) {
TRACE(("Job hack\n"));
/* "jobs": we do not want to clear job list for it,
* instead we remove only _its_ own_ job from job list.
* This makes "jobs .... | cat" more useful.
*/
freejob(curjob);
return;
}
#endif
for (jp = curjob; jp; jp = jp->prev_job)
freejob(jp);
jobless = 0;
}
/* Called after fork(), in parent */
#if !JOBS
#define forkparent(jp, n, mode, pid) forkparent(jp, mode, pid)
#endif
static void
forkparent(struct job *jp, union node *n, int mode, pid_t pid)
{
TRACE(("In parent shell: child = %d\n", pid));
if (!jp) {
/* jp is NULL when called by openhere() for heredoc support */
while (jobless && dowait(DOWAIT_NONBLOCK, NULL) > 0)
continue;
jobless++;
return;
}
#if JOBS
if (mode != FORK_NOJOB && jp->jobctl) {
int pgrp;
if (jp->nprocs == 0)
pgrp = pid;
else
pgrp = jp->ps[0].ps_pid;
/* This can fail because we are doing it in the child also */
setpgid(pid, pgrp);
}
#endif
if (mode == FORK_BG) {
backgndpid = pid; /* set $! */
set_curjob(jp, CUR_RUNNING);
}
if (jp) {
struct procstat *ps = &jp->ps[jp->nprocs++];
ps->ps_pid = pid;
ps->ps_status = -1;
ps->ps_cmd = nullstr;
#if JOBS
if (doing_jobctl && n)
ps->ps_cmd = commandtext(n);
#endif
}
}
/* jp and n are NULL when called by openhere() for heredoc support */
static int
forkshell(struct job *jp, union node *n, int mode)
{
int pid;
TRACE(("forkshell(%%%d, %p, %d) called\n", jobno(jp), n, mode));
pid = fork();
if (pid < 0) {
TRACE(("Fork failed, errno=%d", errno));
if (jp)
freejob(jp);
ash_msg_and_raise_error("can't fork");
}
if (pid == 0) {
CLEAR_RANDOM_T(&random_gen); /* or else $RANDOM repeats in child */
forkchild(jp, n, mode);
} else {
forkparent(jp, n, mode, pid);
}
return pid;
}
/*
* Wait for job to finish.
*
* Under job control we have the problem that while a child process
* is running interrupts generated by the user are sent to the child
* but not to the shell. This means that an infinite loop started by
* an interactive user may be hard to kill. With job control turned off,
* an interactive user may place an interactive program inside a loop.
* If the interactive program catches interrupts, the user doesn't want
* these interrupts to also abort the loop. The approach we take here
* is to have the shell ignore interrupt signals while waiting for a
* foreground process to terminate, and then send itself an interrupt
* signal if the child process was terminated by an interrupt signal.
* Unfortunately, some programs want to do a bit of cleanup and then
* exit on interrupt; unless these processes terminate themselves by
* sending a signal to themselves (instead of calling exit) they will
* confuse this approach.
*
* Called with interrupts off.
*/
static int
waitforjob(struct job *jp)
{
int st;
TRACE(("waitforjob(%%%d) called\n", jobno(jp)));
INT_OFF;
while (jp->state == JOBRUNNING) {
/* In non-interactive shells, we _can_ get
* a keyboard signal here and be EINTRed,
* but we just loop back, waiting for command to complete.
*
* man bash:
* "If bash is waiting for a command to complete and receives
* a signal for which a trap has been set, the trap
* will not be executed until the command completes."
*
* Reality is that even if trap is not set, bash
* will not act on the signal until command completes.
* Try this. sleep5intoff.c:
* #include <signal.h>
* #include <unistd.h>
* int main() {
* sigset_t set;
* sigemptyset(&set);
* sigaddset(&set, SIGINT);
* sigaddset(&set, SIGQUIT);
* sigprocmask(SIG_BLOCK, &set, NULL);
* sleep(5);
* return 0;
* }
* $ bash -c './sleep5intoff; echo hi'
* ^C^C^C^C <--- pressing ^C once a second
* $ _
* $ bash -c './sleep5intoff; echo hi'
* ^\^\^\^\hi <--- pressing ^\ (SIGQUIT)
* $ _
*/
dowait(DOWAIT_BLOCK, jp);
}
INT_ON;
st = getstatus(jp);
#if JOBS
if (jp->jobctl) {
xtcsetpgrp(ttyfd, rootpid);
/*
* This is truly gross.
* If we're doing job control, then we did a TIOCSPGRP which
* caused us (the shell) to no longer be in the controlling
* session -- so we wouldn't have seen any ^C/SIGINT. So, we
* intuit from the subprocess exit status whether a SIGINT
* occurred, and if so interrupt ourselves. Yuck. - mycroft
*/
if (jp->sigint) /* TODO: do the same with all signals */
raise(SIGINT); /* ... by raise(jp->sig) instead? */
}
if (jp->state == JOBDONE)
#endif
freejob(jp);
return st;
}
/*
* return 1 if there are stopped jobs, otherwise 0
*/
static int
stoppedjobs(void)
{
struct job *jp;
int retval;
retval = 0;
if (job_warning)
goto out;
jp = curjob;
if (jp && jp->state == JOBSTOPPED) {
out2str("You have stopped jobs.\n");
job_warning = 2;
retval++;
}
out:
return retval;
}
/*
* Code for dealing with input/output redirection.
*/
#undef EMPTY
#undef CLOSED
#define EMPTY -2 /* marks an unused slot in redirtab */
#define CLOSED -3 /* marks a slot of previously-closed fd */
/*
* Open a file in noclobber mode.
* The code was copied from bash.
*/
static int
noclobberopen(const char *fname)
{
int r, fd;
struct stat finfo, finfo2;
/*
* If the file exists and is a regular file, return an error
* immediately.
*/
r = stat(fname, &finfo);
if (r == 0 && S_ISREG(finfo.st_mode)) {
errno = EEXIST;
return -1;
}
/*
* If the file was not present (r != 0), make sure we open it
* exclusively so that if it is created before we open it, our open
* will fail. Make sure that we do not truncate an existing file.
* Note that we don't turn on O_EXCL unless the stat failed -- if the
* file was not a regular file, we leave O_EXCL off.
*/
if (r != 0)
return open(fname, O_WRONLY|O_CREAT|O_EXCL, 0666);
fd = open(fname, O_WRONLY|O_CREAT, 0666);
/* If the open failed, return the file descriptor right away. */
if (fd < 0)
return fd;
/*
* OK, the open succeeded, but the file may have been changed from a
* non-regular file to a regular file between the stat and the open.
* We are assuming that the O_EXCL open handles the case where FILENAME
* did not exist and is symlinked to an existing file between the stat
* and open.
*/
/*
* If we can open it and fstat the file descriptor, and neither check
* revealed that it was a regular file, and the file has not been
* replaced, return the file descriptor.
*/
if (fstat(fd, &finfo2) == 0
&& !S_ISREG(finfo2.st_mode)
&& finfo.st_dev == finfo2.st_dev
&& finfo.st_ino == finfo2.st_ino
) {
return fd;
}
/* The file has been replaced. badness. */
close(fd);
errno = EEXIST;
return -1;
}
/*
* Handle here documents. Normally we fork off a process to write the
* data to a pipe. If the document is short, we can stuff the data in
* the pipe without forking.
*/
/* openhere needs this forward reference */
static void expandhere(union node *arg, int fd);
static int
openhere(union node *redir)
{
int pip[2];
size_t len = 0;
if (pipe(pip) < 0)
ash_msg_and_raise_error("pipe call failed");
if (redir->type == NHERE) {
len = strlen(redir->nhere.doc->narg.text);
if (len <= PIPE_BUF) {
full_write(pip[1], redir->nhere.doc->narg.text, len);
goto out;
}
}
if (forkshell((struct job *)NULL, (union node *)NULL, FORK_NOJOB) == 0) {
/* child */
close(pip[0]);
ignoresig(SIGINT); //signal(SIGINT, SIG_IGN);
ignoresig(SIGQUIT); //signal(SIGQUIT, SIG_IGN);
ignoresig(SIGHUP); //signal(SIGHUP, SIG_IGN);
ignoresig(SIGTSTP); //signal(SIGTSTP, SIG_IGN);
signal(SIGPIPE, SIG_DFL);
if (redir->type == NHERE)
full_write(pip[1], redir->nhere.doc->narg.text, len);
else /* NXHERE */
expandhere(redir->nhere.doc, pip[1]);
_exit(EXIT_SUCCESS);
}
out:
close(pip[1]);
return pip[0];
}
static int
openredirect(union node *redir)
{
char *fname;
int f;
switch (redir->nfile.type) {
/* Can't happen, our single caller does this itself */
// case NTOFD:
// case NFROMFD:
// return -1;
case NHERE:
case NXHERE:
return openhere(redir);
}
/* For N[X]HERE, reading redir->nfile.expfname would touch beyond
* allocated space. Do it only when we know it is safe.
*/
fname = redir->nfile.expfname;
switch (redir->nfile.type) {
default:
#if DEBUG
abort();
#endif
case NFROM:
f = open(fname, O_RDONLY);
if (f < 0)
goto eopen;
break;
case NFROMTO:
f = open(fname, O_RDWR|O_CREAT, 0666);
if (f < 0)
goto ecreate;
break;
case NTO:
#if ENABLE_ASH_BASH_COMPAT
case NTO2:
#endif
/* Take care of noclobber mode. */
if (Cflag) {
f = noclobberopen(fname);
if (f < 0)
goto ecreate;
break;
}
/* FALLTHROUGH */
case NCLOBBER:
f = open(fname, O_WRONLY|O_CREAT|O_TRUNC, 0666);
if (f < 0)
goto ecreate;
break;
case NAPPEND:
f = open(fname, O_WRONLY|O_CREAT|O_APPEND, 0666);
if (f < 0)
goto ecreate;
break;
}
return f;
ecreate:
ash_msg_and_raise_error("can't create %s: %s", fname, errmsg(errno, "nonexistent directory"));
eopen:
ash_msg_and_raise_error("can't open %s: %s", fname, errmsg(errno, "no such file"));
}
/*
* Copy a file descriptor to be >= 10. Throws exception on error.
*/
static int
savefd(int from)
{
int newfd;
int err;
newfd = fcntl(from, F_DUPFD, 10);
err = newfd < 0 ? errno : 0;
if (err != EBADF) {
if (err)
ash_msg_and_raise_error("%d: %m", from);
close(from);
fcntl(newfd, F_SETFD, FD_CLOEXEC);
}
return newfd;
}
static int
dup2_or_raise(int from, int to)
{
int newfd;
newfd = (from != to) ? dup2(from, to) : to;
if (newfd < 0) {
/* Happens when source fd is not open: try "echo >&99" */
ash_msg_and_raise_error("%d: %m", from);
}
return newfd;
}
/* Struct def and variable are moved down to the first usage site */
struct two_fd_t {
int orig, copy;
};
struct redirtab {
struct redirtab *next;
int pair_count;
struct two_fd_t two_fd[];
};
#define redirlist (G_var.redirlist)
enum {
COPYFD_RESTORE = (int)~(INT_MAX),
};
static int
need_to_remember(struct redirtab *rp, int fd)
{
int i;
if (!rp) /* remembering was not requested */
return 0;
for (i = 0; i < rp->pair_count; i++) {
if (rp->two_fd[i].orig == fd) {
/* already remembered */
return 0;
}
}
return 1;
}
/* "hidden" fd is a fd used to read scripts, or a copy of such */
static int
is_hidden_fd(struct redirtab *rp, int fd)
{
int i;
struct parsefile *pf;
if (fd == -1)
return 0;
/* Check open scripts' fds */
pf = g_parsefile;
while (pf) {
/* We skip pf_fd == 0 case because of the following case:
* $ ash # running ash interactively
* $ . ./script.sh
* and in script.sh: "exec 9>&0".
* Even though top-level pf_fd _is_ 0,
* it's still ok to use it: "read" builtin uses it,
* why should we cripple "exec" builtin?
*/
if (pf->pf_fd > 0 && fd == pf->pf_fd) {
return 1;
}
pf = pf->prev;
}
if (!rp)
return 0;
/* Check saved fds of redirects */
fd |= COPYFD_RESTORE;
for (i = 0; i < rp->pair_count; i++) {
if (rp->two_fd[i].copy == fd) {
return 1;
}
}
return 0;
}
/*
* Process a list of redirection commands. If the REDIR_PUSH flag is set,
* old file descriptors are stashed away so that the redirection can be
* undone by calling popredir.
*/
/* flags passed to redirect */
#define REDIR_PUSH 01 /* save previous values of file descriptors */
#define REDIR_SAVEFD2 03 /* set preverrout */
static void
redirect(union node *redir, int flags)
{
struct redirtab *sv;
int sv_pos;
int i;
int fd;
int newfd;
int copied_fd2 = -1;
if (!redir) {
return;
}
sv = NULL;
sv_pos = 0;
INT_OFF;
if (flags & REDIR_PUSH) {
union node *tmp = redir;
do {
sv_pos++;
#if ENABLE_ASH_BASH_COMPAT
if (tmp->nfile.type == NTO2)
sv_pos++;
#endif
tmp = tmp->nfile.next;
} while (tmp);
sv = ckmalloc(sizeof(*sv) + sv_pos * sizeof(sv->two_fd[0]));
sv->next = redirlist;
sv->pair_count = sv_pos;
redirlist = sv;
while (sv_pos > 0) {
sv_pos--;
sv->two_fd[sv_pos].orig = sv->two_fd[sv_pos].copy = EMPTY;
}
}
do {
int right_fd = -1;
fd = redir->nfile.fd;
if (redir->nfile.type == NTOFD || redir->nfile.type == NFROMFD) {
right_fd = redir->ndup.dupfd;
//bb_error_msg("doing %d > %d", fd, right_fd);
/* redirect from/to same file descriptor? */
if (right_fd == fd)
continue;
/* "echo >&10" and 10 is a fd opened to a sh script? */
if (is_hidden_fd(sv, right_fd)) {
errno = EBADF; /* as if it is closed */
ash_msg_and_raise_error("%d: %m", right_fd);
}
newfd = -1;
} else {
newfd = openredirect(redir); /* always >= 0 */
if (fd == newfd) {
/* Descriptor wasn't open before redirect.
* Mark it for close in the future */
if (need_to_remember(sv, fd)) {
goto remember_to_close;
}
continue;
}
}
#if ENABLE_ASH_BASH_COMPAT
redirect_more:
#endif
if (need_to_remember(sv, fd)) {
/* Copy old descriptor */
/* Careful to not accidentally "save"
* to the same fd as right side fd in N>&M */
int minfd = right_fd < 10 ? 10 : right_fd + 1;
i = fcntl(fd, F_DUPFD, minfd);
/* You'd expect copy to be CLOEXECed. Currently these extra "saved" fds
* are closed in popredir() in the child, preventing them from leaking
* into child. (popredir() also cleans up the mess in case of failures)
*/
if (i == -1) {
i = errno;
if (i != EBADF) {
/* Strange error (e.g. "too many files" EMFILE?) */
if (newfd >= 0)
close(newfd);
errno = i;
ash_msg_and_raise_error("%d: %m", fd);
/* NOTREACHED */
}
/* EBADF: it is not open - good, remember to close it */
remember_to_close:
i = CLOSED;
} else { /* fd is open, save its copy */
/* "exec fd>&-" should not close fds
* which point to script file(s).
* Force them to be restored afterwards */
if (is_hidden_fd(sv, fd))
i |= COPYFD_RESTORE;
}
if (fd == 2)
copied_fd2 = i;
sv->two_fd[sv_pos].orig = fd;
sv->two_fd[sv_pos].copy = i;
sv_pos++;
}
if (newfd < 0) {
/* NTOFD/NFROMFD: copy redir->ndup.dupfd to fd */
if (redir->ndup.dupfd < 0) { /* "fd>&-" */
/* Don't want to trigger debugging */
if (fd != -1)
close(fd);
} else {
dup2_or_raise(redir->ndup.dupfd, fd);
}
} else if (fd != newfd) { /* move newfd to fd */
dup2_or_raise(newfd, fd);
#if ENABLE_ASH_BASH_COMPAT
if (!(redir->nfile.type == NTO2 && fd == 2))
#endif
close(newfd);
}
#if ENABLE_ASH_BASH_COMPAT
if (redir->nfile.type == NTO2 && fd == 1) {
/* We already redirected it to fd 1, now copy it to 2 */
newfd = 1;
fd = 2;
goto redirect_more;
}
#endif
} while ((redir = redir->nfile.next) != NULL);
INT_ON;
if ((flags & REDIR_SAVEFD2) && copied_fd2 >= 0)
preverrout_fd = copied_fd2;
}
/*
* Undo the effects of the last redirection.
*/
static void
popredir(int drop, int restore)
{
struct redirtab *rp;
int i;
if (redirlist == NULL)
return;
INT_OFF;
rp = redirlist;
for (i = 0; i < rp->pair_count; i++) {
int fd = rp->two_fd[i].orig;
int copy = rp->two_fd[i].copy;
if (copy == CLOSED) {
if (!drop)
close(fd);
continue;
}
if (copy != EMPTY) {
if (!drop || (restore && (copy & COPYFD_RESTORE))) {
copy &= ~COPYFD_RESTORE;
/*close(fd);*/
dup2_or_raise(copy, fd);
}
close(copy & ~COPYFD_RESTORE);
}
}
redirlist = rp->next;
free(rp);
INT_ON;
}
/*
* Undo all redirections. Called on error or interrupt.
*/
static int
redirectsafe(union node *redir, int flags)
{
int err;
volatile int saveint;
struct jmploc *volatile savehandler = exception_handler;
struct jmploc jmploc;
SAVE_INT(saveint);
/* "echo 9>/dev/null; echo >&9; echo result: $?" - result should be 1, not 2! */
err = setjmp(jmploc.loc); // huh?? was = setjmp(jmploc.loc) * 2;
if (!err) {
exception_handler = &jmploc;
redirect(redir, flags);
}
exception_handler = savehandler;
if (err && exception_type != EXERROR)
longjmp(exception_handler->loc, 1);
RESTORE_INT(saveint);
return err;
}
/* ============ Routines to expand arguments to commands
*
* We have to deal with backquotes, shell variables, and file metacharacters.
*/
#if ENABLE_FEATURE_SH_MATH
static arith_t
ash_arith(const char *s)
{
arith_state_t math_state;
arith_t result;
math_state.lookupvar = lookupvar;
math_state.setvar = setvar0;
//math_state.endofname = endofname;
INT_OFF;
result = arith(&math_state, s);
if (math_state.errmsg)
ash_msg_and_raise_error(math_state.errmsg);
INT_ON;
return result;
}
#endif
/*
* expandarg flags
*/
#define EXP_FULL 0x1 /* perform word splitting & file globbing */
#define EXP_TILDE 0x2 /* do normal tilde expansion */
#define EXP_VARTILDE 0x4 /* expand tildes in an assignment */
#define EXP_REDIR 0x8 /* file glob for a redirection (1 match only) */
/* ^^^^^^^^^^^^^^ this is meant to support constructs such as "cmd >file*.txt"
* POSIX says for this case:
* Pathname expansion shall not be performed on the word by a
* non-interactive shell; an interactive shell may perform it, but shall
* do so only when the expansion would result in one word.
* Currently, our code complies to the above rule by never globbing
* redirection filenames.
* Bash performs globbing, unless it is non-interactive and in POSIX mode.
* (this means that on a typical Linux distro, bash almost always
* performs globbing, and thus diverges from what we do).
*/
#define EXP_CASE 0x10 /* keeps quotes around for CASE pattern */
#define EXP_QPAT 0x20 /* pattern in quoted parameter expansion */
#define EXP_VARTILDE2 0x40 /* expand tildes after colons only */
#define EXP_WORD 0x80 /* expand word in parameter expansion */
#define EXP_QUOTED 0x100 /* expand word in double quotes */
/*
* rmescape() flags
*/
#define RMESCAPE_ALLOC 0x1 /* Allocate a new string */
#define RMESCAPE_GLOB 0x2 /* Add backslashes for glob */
#define RMESCAPE_GROW 0x8 /* Grow strings instead of stalloc */
#define RMESCAPE_HEAP 0x10 /* Malloc strings instead of stalloc */
#define RMESCAPE_SLASH 0x20 /* Stop globbing after slash */
/* Add CTLESC when necessary. */
#define QUOTES_ESC (EXP_FULL | EXP_CASE | EXP_QPAT | EXP_REDIR)
/* Do not skip NUL characters. */
#define QUOTES_KEEPNUL EXP_TILDE
/*
* Structure specifying which parts of the string should be searched
* for IFS characters.
*/
struct ifsregion {
struct ifsregion *next; /* next region in list */
int begoff; /* offset of start of region */
int endoff; /* offset of end of region */
int nulonly; /* search for nul bytes only */
};
struct arglist {
struct strlist *list;
struct strlist **lastp;
};
/* output of current string */
static char *expdest;
/* list of back quote expressions */
static struct nodelist *argbackq;
/* first struct in list of ifs regions */
static struct ifsregion ifsfirst;
/* last struct in list */
static struct ifsregion *ifslastp;
/* holds expanded arg list */
static struct arglist exparg;
/*
* Our own itoa().
*/
#if !ENABLE_FEATURE_SH_MATH
/* cvtnum() is used even if math support is off (to prepare $? values and such) */
typedef long arith_t;
# define ARITH_FMT "%ld"
#endif
static int
cvtnum(arith_t num)
{
int len;
expdest = makestrspace(sizeof(arith_t)*3 + 2, expdest);
len = fmtstr(expdest, sizeof(arith_t)*3 + 2, ARITH_FMT, num);
STADJUST(len, expdest);
return len;
}
/*
* Break the argument string into pieces based upon IFS and add the
* strings to the argument list. The regions of the string to be
* searched for IFS characters have been stored by recordregion.
*/
static void
ifsbreakup(char *string, struct arglist *arglist)
{
struct ifsregion *ifsp;
struct strlist *sp;
char *start;
char *p;
char *q;
const char *ifs, *realifs;
int ifsspc;
int nulonly;
start = string;
if (ifslastp != NULL) {
ifsspc = 0;
nulonly = 0;
realifs = ifsset() ? ifsval() : defifs;
ifsp = &ifsfirst;
do {
p = string + ifsp->begoff;
nulonly = ifsp->nulonly;
ifs = nulonly ? nullstr : realifs;
ifsspc = 0;
while (p < string + ifsp->endoff) {
q = p;
if ((unsigned char)*p == CTLESC)
p++;
if (!strchr(ifs, *p)) {
p++;
continue;
}
if (!nulonly)
ifsspc = (strchr(defifs, *p) != NULL);
/* Ignore IFS whitespace at start */
if (q == start && ifsspc) {
p++;
start = p;
continue;
}
*q = '\0';
sp = stzalloc(sizeof(*sp));
sp->text = start;
*arglist->lastp = sp;
arglist->lastp = &sp->next;
p++;
if (!nulonly) {
for (;;) {
if (p >= string + ifsp->endoff) {
break;
}
q = p;
if ((unsigned char)*p == CTLESC)
p++;
if (strchr(ifs, *p) == NULL) {
p = q;
break;
}
if (strchr(defifs, *p) == NULL) {
if (ifsspc) {
p++;
ifsspc = 0;
} else {
p = q;
break;
}
} else
p++;
}
}
start = p;
} /* while */
ifsp = ifsp->next;
} while (ifsp != NULL);
if (nulonly)
goto add;
}
if (!*start)
return;
add:
sp = stzalloc(sizeof(*sp));
sp->text = start;
*arglist->lastp = sp;
arglist->lastp = &sp->next;
}
static void
ifsfree(void)
{
struct ifsregion *p = ifsfirst.next;
if (!p)
goto out;
INT_OFF;
do {
struct ifsregion *ifsp;
ifsp = p->next;
free(p);
p = ifsp;
} while (p);
ifsfirst.next = NULL;
INT_ON;
out:
ifslastp = NULL;
}
static size_t
esclen(const char *start, const char *p)
{
size_t esc = 0;
while (p > start && (unsigned char)*--p == CTLESC) {
esc++;
}
return esc;
}
/*
* Remove any CTLESC characters from a string.
*/
static char *
rmescapes(char *str, int flag)
{
static const char qchars[] ALIGN1 = {
IF_ASH_BASH_COMPAT('/',) CTLESC, CTLQUOTEMARK, '\0' };
char *p, *q, *r;
unsigned inquotes;
unsigned protect_against_glob;
unsigned globbing;
IF_ASH_BASH_COMPAT(unsigned slash = flag & RMESCAPE_SLASH;)
p = strpbrk(str, qchars IF_ASH_BASH_COMPAT(+ !slash));
if (!p)
return str;
q = p;
r = str;
if (flag & RMESCAPE_ALLOC) {
size_t len = p - str;
size_t fulllen = len + strlen(p) + 1;
if (flag & RMESCAPE_GROW) {
int strloc = str - (char *)stackblock();
r = makestrspace(fulllen, expdest);
/* p and str may be invalidated by makestrspace */
str = (char *)stackblock() + strloc;
p = str + len;
} else if (flag & RMESCAPE_HEAP) {
r = ckmalloc(fulllen);
} else {
r = stalloc(fulllen);
}
q = r;
if (len > 0) {
q = (char *)memcpy(q, str, len) + len;
}
}
inquotes = 0;
globbing = flag & RMESCAPE_GLOB;
protect_against_glob = globbing;
while (*p) {
if ((unsigned char)*p == CTLQUOTEMARK) {
// Note: both inquotes and protect_against_glob only affect whether
inquotes = ~inquotes;
p++;
protect_against_glob = globbing;
continue;
}
if ((unsigned char)*p == CTLESC) {
p++;
#if DEBUG
if (*p == '\0')
ash_msg_and_raise_error("CTLESC at EOL (shouldn't happen)");
#endif
if (protect_against_glob) {
*q++ = '\\';
}
} else if (*p == '\\' && !inquotes) {
/* naked back slash */
protect_against_glob = 0;
goto copy;
}
#if ENABLE_ASH_BASH_COMPAT
else if (*p == '/' && slash) {
/* stop handling globbing and mark location of slash */
globbing = slash = 0;
*p = CTLESC;
}
#endif
protect_against_glob = globbing;
copy:
*q++ = *p++;
}
*q = '\0';
if (flag & RMESCAPE_GROW) {
expdest = r;
STADJUST(q - r + 1, expdest);
}
return r;
}
#define pmatch(a, b) !fnmatch((a), (b), 0)
/*
* Prepare a pattern for a expmeta (internal glob(3)) call.
*
* Returns an stalloced string.
*/
static char *
preglob(const char *pattern, int flag)
{
return rmescapes((char *)pattern, flag | RMESCAPE_GLOB);
}
/*
* Put a string on the stack.
*/
static void
memtodest(const char *p, size_t len, int syntax, int quotes)
{
char *q;
if (!len)
return;
q = makestrspace((quotes & QUOTES_ESC) ? len * 2 : len, expdest);
do {
unsigned char c = *p++;
if (c) {
if (quotes & QUOTES_ESC) {
int n = SIT(c, syntax);
if (n == CCTL
|| (((quotes & EXP_FULL) || syntax != BASESYNTAX)
&& n == CBACK
)
) {
USTPUTC(CTLESC, q);
}
}
} else if (!(quotes & QUOTES_KEEPNUL))
continue;
USTPUTC(c, q);
} while (--len);
expdest = q;
}
static size_t
strtodest(const char *p, int syntax, int quotes)
{
size_t len = strlen(p);
memtodest(p, len, syntax, quotes);
return len;
}
/*
* Record the fact that we have to scan this region of the
* string for IFS characters.
*/
static void
recordregion(int start, int end, int nulonly)
{
struct ifsregion *ifsp;
if (ifslastp == NULL) {
ifsp = &ifsfirst;
} else {
INT_OFF;
ifsp = ckzalloc(sizeof(*ifsp));
/*ifsp->next = NULL; - ckzalloc did it */
ifslastp->next = ifsp;
INT_ON;
}
ifslastp = ifsp;
ifslastp->begoff = start;
ifslastp->endoff = end;
ifslastp->nulonly = nulonly;
}
static void
removerecordregions(int endoff)
{
if (ifslastp == NULL)
return;
if (ifsfirst.endoff > endoff) {
while (ifsfirst.next) {
struct ifsregion *ifsp;
INT_OFF;
ifsp = ifsfirst.next->next;
free(ifsfirst.next);
ifsfirst.next = ifsp;
INT_ON;
}
if (ifsfirst.begoff > endoff) {
ifslastp = NULL;
} else {
ifslastp = &ifsfirst;
ifsfirst.endoff = endoff;
}
return;
}
ifslastp = &ifsfirst;
while (ifslastp->next && ifslastp->next->begoff < endoff)
ifslastp = ifslastp->next;
while (ifslastp->next) {
struct ifsregion *ifsp;
INT_OFF;
ifsp = ifslastp->next->next;
free(ifslastp->next);
ifslastp->next = ifsp;
INT_ON;
}
if (ifslastp->endoff > endoff)
ifslastp->endoff = endoff;
}
static char *
exptilde(char *startp, char *p, int flags)
{
unsigned char c;
char *name;
struct passwd *pw;
const char *home;
int quotes = flags & QUOTES_ESC;
name = p + 1;
while ((c = *++p) != '\0') {
switch (c) {
case CTLESC:
return startp;
case CTLQUOTEMARK:
return startp;
case ':':
if (flags & EXP_VARTILDE)
goto done;
break;
case '/':
case CTLENDVAR:
goto done;
}
}
done:
*p = '\0';
if (*name == '\0') {
home = lookupvar("HOME");
} else {
pw = getpwnam(name);
if (pw == NULL)
goto lose;
home = pw->pw_dir;
}
if (!home || !*home)
goto lose;
*p = c;
strtodest(home, SQSYNTAX, quotes);
return p;
lose:
*p = c;
return startp;
}
/*
* Execute a command inside back quotes. If it's a builtin command, we
* want to save its output in a block obtained from malloc. Otherwise
* we fork off a subprocess and get the output of the command via a pipe.
* Should be called with interrupts off.
*/
struct backcmd { /* result of evalbackcmd */
int fd; /* file descriptor to read from */
int nleft; /* number of chars in buffer */
char *buf; /* buffer */
struct job *jp; /* job structure for command */
};
/* These forward decls are needed to use "eval" code for backticks handling: */
#define EV_EXIT 01 /* exit after evaluating tree */
static int evaltree(union node *, int);
static void FAST_FUNC
evalbackcmd(union node *n, struct backcmd *result)
{
int pip[2];
struct job *jp;
result->fd = -1;
result->buf = NULL;
result->nleft = 0;
result->jp = NULL;
if (n == NULL) {
goto out;
}
if (pipe(pip) < 0)
ash_msg_and_raise_error("pipe call failed");
jp = makejob(/*n,*/ 1);
if (forkshell(jp, n, FORK_NOJOB) == 0) {
/* child */
FORCE_INT_ON;
close(pip[0]);
if (pip[1] != 1) {
/*close(1);*/
dup2_or_raise(pip[1], 1);
close(pip[1]);
}
/* TODO: eflag clearing makes the following not abort:
* ash -c 'set -e; z=$(false;echo foo); echo $z'
* which is what bash does (unless it is in POSIX mode).
* dash deleted "eflag = 0" line in the commit
* Date: Mon, 28 Jun 2010 17:11:58 +1000
* [EVAL] Don't clear eflag in evalbackcmd
* For now, preserve bash-like behavior, it seems to be somewhat more useful:
*/
eflag = 0;
ifsfree();
evaltree(n, EV_EXIT); /* actually evaltreenr... */
/* NOTREACHED */
}
/* parent */
close(pip[1]);
result->fd = pip[0];
result->jp = jp;
out:
TRACE(("evalbackcmd done: fd=%d buf=0x%x nleft=%d jp=0x%x\n",
result->fd, result->buf, result->nleft, result->jp));
}
/*
* Expand stuff in backwards quotes.
*/
static void
expbackq(union node *cmd, int flag)
{
struct backcmd in;
int i;
char buf[128];
char *p;
char *dest;
int startloc;
int syntax = flag & EXP_QUOTED ? DQSYNTAX : BASESYNTAX;
struct stackmark smark;
INT_OFF;
startloc = expdest - (char *)stackblock();
pushstackmark(&smark, startloc);
evalbackcmd(cmd, &in);
popstackmark(&smark);
p = in.buf;
i = in.nleft;
if (i == 0)
goto read;
for (;;) {
memtodest(p, i, syntax, flag & QUOTES_ESC);
read:
if (in.fd < 0)
break;
i = nonblock_immune_read(in.fd, buf, sizeof(buf));
TRACE(("expbackq: read returns %d\n", i));
if (i <= 0)
break;
p = buf;
}
free(in.buf);
if (in.fd >= 0) {
close(in.fd);
back_exitstatus = waitforjob(in.jp);
}
INT_ON;
/* Eat all trailing newlines */
dest = expdest;
for (; dest > (char *)stackblock() && dest[-1] == '\n';)
STUNPUTC(dest);
expdest = dest;
if (!(flag & EXP_QUOTED))
recordregion(startloc, dest - (char *)stackblock(), 0);
TRACE(("evalbackq: size:%d:'%.*s'\n",
(int)((dest - (char *)stackblock()) - startloc),
(int)((dest - (char *)stackblock()) - startloc),
stackblock() + startloc));
}
#if ENABLE_FEATURE_SH_MATH
/*
* Expand arithmetic expression. Backup to start of expression,
* evaluate, place result in (backed up) result, adjust string position.
*/
static void
expari(int flag)
{
char *p, *start;
int begoff;
int len;
/* ifsfree(); */
/*
* This routine is slightly over-complicated for
* efficiency. Next we scan backwards looking for the
* start of arithmetic.
*/
start = stackblock();
p = expdest - 1;
*p = '\0';
p--;
while (1) {
int esc;
while ((unsigned char)*p != CTLARI) {
p--;
#if DEBUG
if (p < start) {
ash_msg_and_raise_error("missing CTLARI (shouldn't happen)");
}
#endif
}
esc = esclen(start, p);
if (!(esc % 2)) {
break;
}
p -= esc + 1;
}
begoff = p - start;
removerecordregions(begoff);
expdest = p;
if (flag & QUOTES_ESC)
rmescapes(p + 1, 0);
len = cvtnum(ash_arith(p + 1));
if (!(flag & EXP_QUOTED))
recordregion(begoff, begoff + len, 0);
}
#endif
/* argstr needs it */
static char *evalvar(char *p, int flags, struct strlist *var_str_list);
/*
* Perform variable and command substitution. If EXP_FULL is set, output CTLESC
* characters to allow for further processing. Otherwise treat
* $@ like $* since no splitting will be performed.
*
* var_str_list (can be NULL) is a list of "VAR=val" strings which take precedence
* over shell varables. Needed for "A=a B=$A; echo $B" case - we use it
* for correct expansion of "B=$A" word.
*/
static void
argstr(char *p, int flags, struct strlist *var_str_list)
{
static const char spclchars[] ALIGN1 = {
'=',
':',
CTLQUOTEMARK,
CTLENDVAR,
CTLESC,
CTLVAR,
CTLBACKQ,
#if ENABLE_FEATURE_SH_MATH
CTLENDARI,
#endif
'\0'
};
const char *reject = spclchars;
int breakall = (flags & (EXP_WORD | EXP_QUOTED)) == EXP_WORD;
int inquotes;
size_t length;
int startloc;
if (!(flags & EXP_VARTILDE)) {
reject += 2;
} else if (flags & EXP_VARTILDE2) {
reject++;
}
inquotes = 0;
length = 0;
if (flags & EXP_TILDE) {
char *q;
flags &= ~EXP_TILDE;
tilde:
q = p;
if (*q == '~')
p = exptilde(p, q, flags);
}
start:
startloc = expdest - (char *)stackblock();
for (;;) {
unsigned char c;
length += strcspn(p + length, reject);
c = p[length];
if (c) {
if (!(c & 0x80)
IF_FEATURE_SH_MATH(|| c == CTLENDARI)
) {
/* c == '=' || c == ':' || c == CTLENDARI */
length++;
}
}
if (length > 0) {
int newloc;
expdest = stack_nputstr(p, length, expdest);
newloc = expdest - (char *)stackblock();
if (breakall && !inquotes && newloc > startloc) {
recordregion(startloc, newloc, 0);
}
startloc = newloc;
}
p += length + 1;
length = 0;
switch (c) {
case '\0':
goto breakloop;
case '=':
if (flags & EXP_VARTILDE2) {
p--;
continue;
}
flags |= EXP_VARTILDE2;
reject++;
/* fall through */
case ':':
/*
* sort of a hack - expand tildes in variable
* assignments (after the first '=' and after ':'s).
*/
if (*--p == '~') {
goto tilde;
}
continue;
}
switch (c) {
case CTLENDVAR: /* ??? */
goto breakloop;
case CTLQUOTEMARK:
inquotes ^= EXP_QUOTED;
/* "$@" syntax adherence hack */
if (inquotes && !memcmp(p, dolatstr + 1, DOLATSTRLEN - 1)) {
p = evalvar(p + 1, flags | inquotes, /* var_str_list: */ NULL) + 1;
goto start;
}
addquote:
if (flags & QUOTES_ESC) {
p--;
length++;
startloc++;
}
break;
case CTLESC:
startloc++;
length++;
/*
* Quoted parameter expansion pattern: remove quote
* unless inside inner quotes or we have a literal
* backslash.
*/
if (((flags | inquotes) & (EXP_QPAT | EXP_QUOTED)) ==
EXP_QPAT && *p != '\\')
break;
goto addquote;
case CTLVAR:
TRACE(("argstr: evalvar('%s')\n", p));
p = evalvar(p, flags | inquotes, var_str_list);
TRACE(("argstr: evalvar:'%s'\n", (char *)stackblock()));
goto start;
case CTLBACKQ:
expbackq(argbackq->n, flags | inquotes);
argbackq = argbackq->next;
goto start;
#if ENABLE_FEATURE_SH_MATH
case CTLENDARI:
p--;
expari(flags | inquotes);
goto start;
#endif
}
}
breakloop: ;
}
static char *
scanleft(char *startp, char *rmesc, char *rmescend UNUSED_PARAM,
char *pattern, int quotes, int zero)
{
char *loc, *loc2;
char c;
loc = startp;
loc2 = rmesc;
do {
int match;
const char *s = loc2;
c = *loc2;
if (zero) {
*loc2 = '\0';
s = rmesc;
}
match = pmatch(pattern, s);
*loc2 = c;
if (match)
return loc;
if (quotes && (unsigned char)*loc == CTLESC)
loc++;
loc++;
loc2++;
} while (c);
return NULL;
}
static char *
scanright(char *startp, char *rmesc, char *rmescend,
char *pattern, int quotes, int match_at_start)
{
#if !ENABLE_ASH_OPTIMIZE_FOR_SIZE
int try2optimize = match_at_start;
#endif
int esc = 0;
char *loc;
char *loc2;
/* If we called by "${v/pattern/repl}" or "${v//pattern/repl}":
* startp="escaped_value_of_v" rmesc="raw_value_of_v"
* rmescend=""(ptr to NUL in rmesc) pattern="pattern" quotes=match_at_start=1
* Logic:
* loc starts at NUL at the end of startp, loc2 starts at the end of rmesc,
* and on each iteration they go back two/one char until they reach the beginning.
* We try to find a match in "raw_value_of_v", "raw_value_of_", "raw_value_of" etc.
*/
/* TODO: document in what other circumstances we are called. */
for (loc = pattern - 1, loc2 = rmescend; loc >= startp; loc2--) {
int match;
char c = *loc2;
const char *s = loc2;
if (match_at_start) {
*loc2 = '\0';
s = rmesc;
}
match = pmatch(pattern, s);
//bb_error_msg("pmatch(pattern:'%s',s:'%s'):%d", pattern, s, match);
*loc2 = c;
if (match)
return loc;
#if !ENABLE_ASH_OPTIMIZE_FOR_SIZE
if (try2optimize) {
/* Maybe we can optimize this:
* if pattern ends with unescaped *, we can avoid checking
* shorter strings: if "foo*" doesnt match "raw_value_of_v",
* it wont match truncated "raw_value_of_" strings too.
*/
unsigned plen = strlen(pattern);
/* Does it end with "*"? */
if (plen != 0 && pattern[--plen] == '*') {
/* "xxxx*" is not escaped */
/* "xxx\*" is escaped */
/* "xx\\*" is not escaped */
/* "x\\\*" is escaped */
int slashes = 0;
while (plen != 0 && pattern[--plen] == '\\')
slashes++;
if (!(slashes & 1))
break; /* ends with unescaped "*" */
}
try2optimize = 0;
}
#endif
loc--;
if (quotes) {
if (--esc < 0) {
esc = esclen(startp, loc);
}
if (esc % 2) {
esc--;
loc--;
}
}
}
return NULL;
}
static void varunset(const char *, const char *, const char *, int) NORETURN;
static void
varunset(const char *end, const char *var, const char *umsg, int varflags)
{
const char *msg;
const char *tail;
tail = nullstr;
msg = "parameter not set";
if (umsg) {
if ((unsigned char)*end == CTLENDVAR) {
if (varflags & VSNUL)
tail = " or null";
} else {
msg = umsg;
}
}
ash_msg_and_raise_error("%.*s: %s%s", (int)(end - var - 1), var, msg, tail);
}
static const char *
subevalvar(char *p, char *varname, int strloc, int subtype,
int startloc, int varflags, int flag, struct strlist *var_str_list)
{
struct nodelist *saveargbackq = argbackq;
int quotes = flag & QUOTES_ESC;
char *startp;
char *loc;
char *rmesc, *rmescend;
char *str;
IF_ASH_BASH_COMPAT(char *repl = NULL;)
IF_ASH_BASH_COMPAT(int pos, len, orig_len;)
int amount, resetloc;
IF_ASH_BASH_COMPAT(int workloc;)
int zero;
char *(*scan)(char*, char*, char*, char*, int, int);
//bb_error_msg("subevalvar(p:'%s',varname:'%s',strloc:%d,subtype:%d,startloc:%d,varflags:%x,quotes:%d)",
// p, varname, strloc, subtype, startloc, varflags, quotes);
argstr(p, EXP_TILDE | (subtype != VSASSIGN && subtype != VSQUESTION ?
(flag & (EXP_QUOTED | EXP_QPAT) ? EXP_QPAT : EXP_CASE) : 0),
var_str_list);
STPUTC('\0', expdest);
argbackq = saveargbackq;
startp = (char *)stackblock() + startloc;
switch (subtype) {
case VSASSIGN:
setvar0(varname, startp);
amount = startp - expdest;
STADJUST(amount, expdest);
return startp;
case VSQUESTION:
varunset(p, varname, startp, varflags);
/* NOTREACHED */
#if ENABLE_ASH_BASH_COMPAT
case VSSUBSTR:
//TODO: support more general format ${v:EXPR:EXPR},
// where EXPR follows $(()) rules
loc = str = stackblock() + strloc;
/* Read POS in ${var:POS:LEN} */
pos = atoi(loc); /* number(loc) errors out on "1:4" */
len = str - startp - 1;
/* *loc != '\0', guaranteed by parser */
if (quotes) {
char *ptr;
/* Adjust the length by the number of escapes */
for (ptr = startp; ptr < (str - 1); ptr++) {
if ((unsigned char)*ptr == CTLESC) {
len--;
ptr++;
}
}
}
orig_len = len;
if (*loc++ == ':') {
/* ${var::LEN} */
len = number(loc);
} else {
/* Skip POS in ${var:POS:LEN} */
len = orig_len;
while (*loc && *loc != ':') {
/* TODO?
* bash complains on: var=qwe; echo ${var:1a:123}
if (!isdigit(*loc))
ash_msg_and_raise_error(msg_illnum, str);
*/
loc++;
}
if (*loc++ == ':') {
len = number(loc);
}
}
if (pos < 0) {
/* ${VAR:$((-n)):l} starts n chars from the end */
pos = orig_len + pos;
}
if ((unsigned)pos >= orig_len) {
/* apart from obvious ${VAR:999999:l},
* covers ${VAR:$((-9999999)):l} - result is ""
* (bash-compat)
*/
pos = 0;
len = 0;
}
if (len > (orig_len - pos))
len = orig_len - pos;
for (str = startp; pos; str++, pos--) {
if (quotes && (unsigned char)*str == CTLESC)
str++;
}
for (loc = startp; len; len--) {
if (quotes && (unsigned char)*str == CTLESC)
*loc++ = *str++;
*loc++ = *str++;
}
*loc = '\0';
amount = loc - expdest;
STADJUST(amount, expdest);
return loc;
#endif
}
resetloc = expdest - (char *)stackblock();
/* We'll comeback here if we grow the stack while handling
* a VSREPLACE or VSREPLACEALL, since our pointers into the
* stack will need rebasing, and we'll need to remove our work
* areas each time
*/
IF_ASH_BASH_COMPAT(restart:)
amount = expdest - ((char *)stackblock() + resetloc);
STADJUST(-amount, expdest);
startp = (char *)stackblock() + startloc;
rmesc = startp;
rmescend = (char *)stackblock() + strloc;
if (quotes) {
rmesc = rmescapes(startp, RMESCAPE_ALLOC | RMESCAPE_GROW);
if (rmesc != startp) {
rmescend = expdest;
startp = (char *)stackblock() + startloc;
}
}
rmescend--;
str = (char *)stackblock() + strloc;
/*
* Example: v='a\bc'; echo ${v/\\b/_\\_\z_}
* The result is a_\_z_c (not a\_\_z_c)!
*
* The search pattern and replace string treat backslashes differently!
* RMESCAPE_SLASH causes preglob to work differently on the pattern
* and string. It's only used on the first call.
*/
preglob(str, IF_ASH_BASH_COMPAT(
(subtype == VSREPLACE || subtype == VSREPLACEALL) && !repl ?
RMESCAPE_SLASH :) 0);
#if ENABLE_ASH_BASH_COMPAT
workloc = expdest - (char *)stackblock();
if (subtype == VSREPLACE || subtype == VSREPLACEALL) {
char *idx, *end;
if (!repl) {
repl = strchr(str, CTLESC);
if (repl)
*repl++ = '\0';
else
repl = nullstr;
}
//bb_error_msg("str:'%s' repl:'%s'", str, repl);
/* If there's no pattern to match, return the expansion unmolested */
if (str[0] == '\0')
return NULL;
len = 0;
idx = startp;
end = str - 1;
while (idx < end) {
try_to_match:
loc = scanright(idx, rmesc, rmescend, str, quotes, 1);
//bb_error_msg("scanright('%s'):'%s'", str, loc);
if (!loc) {
/* No match, advance */
char *restart_detect = stackblock();
skip_matching:
STPUTC(*idx, expdest);
if (quotes && (unsigned char)*idx == CTLESC) {
idx++;
len++;
STPUTC(*idx, expdest);
}
if (stackblock() != restart_detect)
goto restart;
idx++;
len++;
rmesc++;
/* continue; - prone to quadratic behavior, smarter code: */
if (idx >= end)
break;
if (str[0] == '*') {
/* Pattern is "*foo". If "*foo" does not match "long_string",
* it would never match "ong_string" etc, no point in trying.
*/
goto skip_matching;
}
goto try_to_match;
}
if (subtype == VSREPLACEALL) {
while (idx < loc) {
if (quotes && (unsigned char)*idx == CTLESC)
idx++;
idx++;
rmesc++;
}
} else {
idx = loc;
}
//bb_error_msg("repl:'%s'", repl);
for (loc = (char*)repl; *loc; loc++) {
char *restart_detect = stackblock();
if (quotes && *loc == '\\') {
STPUTC(CTLESC, expdest);
len++;
}
STPUTC(*loc, expdest);
if (stackblock() != restart_detect)
goto restart;
len++;
}
if (subtype == VSREPLACE) {
//bb_error_msg("tail:'%s', quotes:%x", idx, quotes);
while (*idx) {
char *restart_detect = stackblock();
STPUTC(*idx, expdest);
if (stackblock() != restart_detect)
goto restart;
len++;
idx++;
}
break;
}
}
/* We've put the replaced text into a buffer at workloc, now
* move it to the right place and adjust the stack.
*/
STPUTC('\0', expdest);
startp = (char *)stackblock() + startloc;
memmove(startp, (char *)stackblock() + workloc, len + 1);
//bb_error_msg("startp:'%s'", startp);
amount = expdest - (startp + len);
STADJUST(-amount, expdest);
return startp;
}
#endif /* ENABLE_ASH_BASH_COMPAT */
subtype -= VSTRIMRIGHT;
#if DEBUG
if (subtype < 0 || subtype > 7)
abort();
#endif
/* zero = (subtype == VSTRIMLEFT || subtype == VSTRIMLEFTMAX) */
zero = subtype >> 1;
/* VSTRIMLEFT/VSTRIMRIGHTMAX -> scanleft */
scan = (subtype & 1) ^ zero ? scanleft : scanright;
loc = scan(startp, rmesc, rmescend, str, quotes, zero);
if (loc) {
if (zero) {
memmove(startp, loc, str - loc);
loc = startp + (str - loc) - 1;
}
*loc = '\0';
amount = loc - expdest;
STADJUST(amount, expdest);
}
return loc;
}
/*
* Add the value of a specialized variable to the stack string.
* name parameter (examples):
* ash -c 'echo $1' name:'1='
* ash -c 'echo $qwe' name:'qwe='
* ash -c 'echo $$' name:'$='
* ash -c 'echo ${$}' name:'$='
* ash -c 'echo ${$##q}' name:'$=q'
* ash -c 'echo ${#$}' name:'$='
* note: examples with bad shell syntax:
* ash -c 'echo ${#$1}' name:'$=1'
* ash -c 'echo ${#1#}' name:'1=#'
*/
static NOINLINE ssize_t
varvalue(char *name, int varflags, int flags, struct strlist *var_str_list, int *quotedp)
{
const char *p;
int num;
int i;
ssize_t len = 0;
int sep;
int quoted = *quotedp;
int subtype = varflags & VSTYPE;
int discard = subtype == VSPLUS || subtype == VSLENGTH;
int quotes = (discard ? 0 : (flags & QUOTES_ESC)) | QUOTES_KEEPNUL;
int syntax;
sep = (flags & EXP_FULL) << CHAR_BIT;
syntax = quoted ? DQSYNTAX : BASESYNTAX;
switch (*name) {
case '$':
num = rootpid;
goto numvar;
case '?':
num = exitstatus;
goto numvar;
case '#':
num = shellparam.nparam;
goto numvar;
case '!':
num = backgndpid;
if (num == 0)
return -1;
numvar:
len = cvtnum(num);
goto check_1char_name;
case '-':
expdest = makestrspace(NOPTS, expdest);
for (i = NOPTS - 1; i >= 0; i--) {
if (optlist[i]) {
USTPUTC(optletters(i), expdest);
len++;
}
}
check_1char_name:
#if 0
/* handles cases similar to ${#$1} */
if (name[2] != '\0')
raise_error_syntax("bad substitution");
#endif
break;
case '@':
if (quoted && sep)
goto param;
/* fall through */
case '*': {
char **ap;
char sepc;
if (quoted)
sep = 0;
sep |= ifsset() ? ifsval()[0] : ' ';
param:
sepc = sep;
*quotedp = !sepc;
ap = shellparam.p;
if (!ap)
return -1;
while ((p = *ap++) != NULL) {
len += strtodest(p, syntax, quotes);
if (*ap && sep) {
len++;
memtodest(&sepc, 1, syntax, quotes);
}
}
break;
} /* case '*' */
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
num = atoi(name); /* number(name) fails on ${N#str} etc */
if (num < 0 || num > shellparam.nparam)
return -1;
p = num ? shellparam.p[num - 1] : arg0;
goto value;
default:
/* NB: name has form "VAR=..." */
/* "A=a B=$A" case: var_str_list is a list of "A=a" strings
* which should be considered before we check variables. */
if (var_str_list) {
unsigned name_len = (strchrnul(name, '=') - name) + 1;
p = NULL;
do {
char *str, *eq;
str = var_str_list->text;
eq = strchr(str, '=');
if (!eq) /* stop at first non-assignment */
break;
eq++;
if (name_len == (unsigned)(eq - str)
&& strncmp(str, name, name_len) == 0
) {
p = eq;
/* goto value; - WRONG! */
/* think "A=1 A=2 B=$A" */
}
var_str_list = var_str_list->next;
} while (var_str_list);
if (p)
goto value;
}
p = lookupvar(name);
value:
if (!p)
return -1;
len = strtodest(p, syntax, quotes);
#if ENABLE_UNICODE_SUPPORT
if (subtype == VSLENGTH && len > 0) {
reinit_unicode_for_ash();
if (unicode_status == UNICODE_ON) {
STADJUST(-len, expdest);
discard = 0;
len = unicode_strlen(p);
}
}
#endif
break;
}
if (discard)
STADJUST(-len, expdest);
return len;
}
/*
* Expand a variable, and return a pointer to the next character in the
* input string.
*/
static char *
evalvar(char *p, int flag, struct strlist *var_str_list)
{
char varflags;
char subtype;
int quoted;
char easy;
char *var;
int patloc;
int startloc;
ssize_t varlen;
varflags = (unsigned char) *p++;
subtype = varflags & VSTYPE;
if (!subtype)
raise_error_syntax("bad substitution");
quoted = flag & EXP_QUOTED;
var = p;
easy = (!quoted || (*var == '@' && shellparam.nparam));
startloc = expdest - (char *)stackblock();
p = strchr(p, '=') + 1; //TODO: use var_end(p)?
again:
varlen = varvalue(var, varflags, flag, var_str_list, &quoted);
if (varflags & VSNUL)
varlen--;
if (subtype == VSPLUS) {
varlen = -1 - varlen;
goto vsplus;
}
if (subtype == VSMINUS) {
vsplus:
if (varlen < 0) {
argstr(
p,
flag | EXP_TILDE | EXP_WORD,
var_str_list
);
goto end;
}
goto record;
}
if (subtype == VSASSIGN || subtype == VSQUESTION) {
if (varlen >= 0)
goto record;
subevalvar(p, var, 0, subtype, startloc, varflags,
flag & ~QUOTES_ESC, var_str_list);
varflags &= ~VSNUL;
/*
* Remove any recorded regions beyond
* start of variable
*/
removerecordregions(startloc);
goto again;
}
if (varlen < 0 && uflag)
varunset(p, var, 0, 0);
if (subtype == VSLENGTH) {
cvtnum(varlen > 0 ? varlen : 0);
goto record;
}
if (subtype == VSNORMAL) {
record:
if (!easy)
goto end;
recordregion(startloc, expdest - (char *)stackblock(), quoted);
goto end;
}
#if DEBUG
switch (subtype) {
case VSTRIMLEFT:
case VSTRIMLEFTMAX:
case VSTRIMRIGHT:
case VSTRIMRIGHTMAX:
#if ENABLE_ASH_BASH_COMPAT
case VSSUBSTR:
case VSREPLACE:
case VSREPLACEALL:
#endif
break;
default:
abort();
}
#endif
if (varlen >= 0) {
/*
* Terminate the string and start recording the pattern
* right after it
*/
STPUTC('\0', expdest);
patloc = expdest - (char *)stackblock();
if (NULL == subevalvar(p, /* varname: */ NULL, patloc, subtype,
startloc, varflags, flag, var_str_list)) {
int amount = expdest - (
(char *)stackblock() + patloc - 1
);
STADJUST(-amount, expdest);
}
/* Remove any recorded regions beyond start of variable */
removerecordregions(startloc);
goto record;
}
end:
if (subtype != VSNORMAL) { /* skip to end of alternative */
int nesting = 1;
for (;;) {
unsigned char c = *p++;
if (c == CTLESC)
p++;
else if (c == CTLBACKQ) {
if (varlen >= 0)
argbackq = argbackq->next;
} else if (c == CTLVAR) {
if ((*p++ & VSTYPE) != VSNORMAL)
nesting++;
} else if (c == CTLENDVAR) {
if (--nesting == 0)
break;
}
}
}
return p;
}
/*
* Add a file name to the list.
*/
static void
addfname(const char *name)
{
struct strlist *sp;
sp = stzalloc(sizeof(*sp));
sp->text = sstrdup(name);
*exparg.lastp = sp;
exparg.lastp = &sp->next;
}
/* If we want to use glob() from libc... */
#if !ENABLE_ASH_INTERNAL_GLOB
/* Add the result of glob() to the list */
static void
addglob(const glob_t *pglob)
{
char **p = pglob->gl_pathv;
do {
addfname(*p);
} while (*++p);
}
static void
expandmeta(struct strlist *str /*, int flag*/)
{
/* TODO - EXP_REDIR */
while (str) {
char *p;
glob_t pglob;
int i;
if (fflag)
goto nometa;
/* Avoid glob() (and thus, stat() et al) for words like "echo" */
p = str->text;
while (*p) {
if (*p == '*')
goto need_glob;
if (*p == '?')
goto need_glob;
if (*p == '[')
goto need_glob;
p++;
}
goto nometa;
need_glob:
INT_OFF;
p = preglob(str->text, RMESCAPE_ALLOC | RMESCAPE_HEAP);
// GLOB_NOMAGIC (GNU): if no *?[ chars in pattern, return it even if no match
// GLOB_NOCHECK: if no match, return unchanged pattern (sans \* escapes?)
//
// glibc 2.24.90 glob(GLOB_NOMAGIC) does not remove backslashes used for escaping:
// if you pass it "file\?", it returns "file\?", not "file?", if no match.
// Which means you need to unescape the string, right? Not so fast:
// if there _is_ a file named "file\?" (with backslash), it is returned
// as "file\?" too (whichever pattern you used to find it, say, "file*").
// You DONT KNOW by looking at the result whether you need to unescape it.
//
// Worse, globbing of "file\?" in a directory with two files, "file?" and "file\?",
// returns "file\?" - which is WRONG: "file\?" pattern matches "file?" file.
// Without GLOB_NOMAGIC, this works correctly ("file?" is returned as a match).
// With GLOB_NOMAGIC | GLOB_NOCHECK, this also works correctly.
// i = glob(p, GLOB_NOMAGIC | GLOB_NOCHECK, NULL, &pglob);
// i = glob(p, GLOB_NOMAGIC, NULL, &pglob);
i = glob(p, 0, NULL, &pglob);
//bb_error_msg("glob('%s'):%d '%s'...", p, i, pglob.gl_pathv ? pglob.gl_pathv[0] : "-");
if (p != str->text)
free(p);
switch (i) {
case 0:
#if 0 // glibc 2.24.90 bug? Patterns like "*/file", when match, don't set GLOB_MAGCHAR
/* GLOB_MAGCHAR is set if *?[ chars were seen (GNU) */
if (!(pglob.gl_flags & GLOB_MAGCHAR))
goto nometa2;
#endif
addglob(&pglob);
globfree(&pglob);
INT_ON;
break;
case GLOB_NOMATCH:
//nometa2:
globfree(&pglob);
INT_ON;
nometa:
*exparg.lastp = str;
rmescapes(str->text, 0);
exparg.lastp = &str->next;
break;
default: /* GLOB_NOSPACE */
globfree(&pglob);
INT_ON;
ash_msg_and_raise_error(bb_msg_memory_exhausted);
}
str = str->next;
}
}
#else
/* ENABLE_ASH_INTERNAL_GLOB: Homegrown globbing code. (dash also has both, uses homegrown one.) */
/*
* Do metacharacter (i.e. *, ?, [...]) expansion.
*/
static void
expmeta(char *expdir, char *enddir, char *name)
{
char *p;
const char *cp;
char *start;
char *endname;
int metaflag;
struct stat statb;
DIR *dirp;
struct dirent *dp;
int atend;
int matchdot;
int esc;
metaflag = 0;
start = name;
for (p = name; esc = 0, *p; p += esc + 1) {
if (*p == '*' || *p == '?')
metaflag = 1;
else if (*p == '[') {
char *q = p + 1;
if (*q == '!')
q++;
for (;;) {
if (*q == '\\')
q++;
if (*q == '/' || *q == '\0')
break;
if (*++q == ']') {
metaflag = 1;
break;
}
}
} else {
if (*p == '\\')
esc++;
if (p[esc] == '/') {
if (metaflag)
break;
start = p + esc + 1;
}
}
}
if (metaflag == 0) { /* we've reached the end of the file name */
if (enddir != expdir)
metaflag++;
p = name;
do {
if (*p == '\\')
p++;
*enddir++ = *p;
} while (*p++);
if (metaflag == 0 || lstat(expdir, &statb) >= 0)
addfname(expdir);
return;
}
endname = p;
if (name < start) {
p = name;
do {
if (*p == '\\')
p++;
*enddir++ = *p++;
} while (p < start);
}
if (enddir == expdir) {
cp = ".";
} else if (enddir == expdir + 1 && *expdir == '/') {
cp = "/";
} else {
cp = expdir;
enddir[-1] = '\0';
}
dirp = opendir(cp);
if (dirp == NULL)
return;
if (enddir != expdir)
enddir[-1] = '/';
if (*endname == 0) {
atend = 1;
} else {
atend = 0;
*endname = '\0';
endname += esc + 1;
}
matchdot = 0;
p = start;
if (*p == '\\')
p++;
if (*p == '.')
matchdot++;
while (!pending_int && (dp = readdir(dirp)) != NULL) {
if (dp->d_name[0] == '.' && !matchdot)
continue;
if (pmatch(start, dp->d_name)) {
if (atend) {
strcpy(enddir, dp->d_name);
addfname(expdir);
} else {
for (p = enddir, cp = dp->d_name; (*p++ = *cp++) != '\0';)
continue;
p[-1] = '/';
expmeta(expdir, p, endname);
}
}
}
closedir(dirp);
if (!atend)
endname[-esc - 1] = esc ? '\\' : '/';
}
static struct strlist *
msort(struct strlist *list, int len)
{
struct strlist *p, *q = NULL;
struct strlist **lpp;
int half;
int n;
if (len <= 1)
return list;
half = len >> 1;
p = list;
for (n = half; --n >= 0;) {
q = p;
p = p->next;
}
q->next = NULL; /* terminate first half of list */
q = msort(list, half); /* sort first half of list */
p = msort(p, len - half); /* sort second half */
lpp = &list;
for (;;) {
#if ENABLE_LOCALE_SUPPORT
if (strcoll(p->text, q->text) < 0)
#else
if (strcmp(p->text, q->text) < 0)
#endif
{
*lpp = p;
lpp = &p->next;
p = *lpp;
if (p == NULL) {
*lpp = q;
break;
}
} else {
*lpp = q;
lpp = &q->next;
q = *lpp;
if (q == NULL) {
*lpp = p;
break;
}
}
}
return list;
}
/*
* Sort the results of file name expansion. It calculates the number of
* strings to sort and then calls msort (short for merge sort) to do the
* work.
*/
static struct strlist *
expsort(struct strlist *str)
{
int len;
struct strlist *sp;
len = 0;
for (sp = str; sp; sp = sp->next)
len++;
return msort(str, len);
}
static void
expandmeta(struct strlist *str /*, int flag*/)
{
static const char metachars[] ALIGN1 = {
'*', '?', '[', 0
};
/* TODO - EXP_REDIR */
while (str) {
char *expdir;
struct strlist **savelastp;
struct strlist *sp;
char *p;
if (fflag)
goto nometa;
if (!strpbrk(str->text, metachars))
goto nometa;
savelastp = exparg.lastp;
INT_OFF;
p = preglob(str->text, RMESCAPE_ALLOC | RMESCAPE_HEAP);
{
int i = strlen(str->text);
//BUGGY estimation of how long expanded name can be
expdir = ckmalloc(i < 2048 ? 2048 : i+1);
}
expmeta(expdir, expdir, p);
free(expdir);
if (p != str->text)
free(p);
INT_ON;
if (exparg.lastp == savelastp) {
/*
* no matches
*/
nometa:
*exparg.lastp = str;
rmescapes(str->text, 0);
exparg.lastp = &str->next;
} else {
*exparg.lastp = NULL;
*savelastp = sp = expsort(*savelastp);
while (sp->next != NULL)
sp = sp->next;
exparg.lastp = &sp->next;
}
str = str->next;
}
}
#endif /* ENABLE_ASH_INTERNAL_GLOB */
/*
* Perform variable substitution and command substitution on an argument,
* placing the resulting list of arguments in arglist. If EXP_FULL is true,
* perform splitting and file name expansion. When arglist is NULL, perform
* here document expansion.
*/
static void
expandarg(union node *arg, struct arglist *arglist, int flag)
{
struct strlist *sp;
char *p;
argbackq = arg->narg.backquote;
STARTSTACKSTR(expdest);
TRACE(("expandarg: argstr('%s',flags:%x)\n", arg->narg.text, flag));
argstr(arg->narg.text, flag,
/* var_str_list: */ arglist ? arglist->list : NULL);
p = _STPUTC('\0', expdest);
expdest = p - 1;
if (arglist == NULL) {
/* here document expanded */
goto out;
}
p = grabstackstr(p);
TRACE(("expandarg: p:'%s'\n", p));
exparg.lastp = &exparg.list;
/*
* TODO - EXP_REDIR
*/
if (flag & EXP_FULL) {
ifsbreakup(p, &exparg);
*exparg.lastp = NULL;
exparg.lastp = &exparg.list;
expandmeta(exparg.list /*, flag*/);
} else {
if (flag & EXP_REDIR) { /*XXX - for now, just remove escapes */
rmescapes(p, 0);
TRACE(("expandarg: rmescapes:'%s'\n", p));
}
sp = stzalloc(sizeof(*sp));
sp->text = p;
*exparg.lastp = sp;
exparg.lastp = &sp->next;
}
*exparg.lastp = NULL;
if (exparg.list) {
*arglist->lastp = exparg.list;
arglist->lastp = exparg.lastp;
}
out:
ifsfree();
}
/*
* Expand shell variables and backquotes inside a here document.
*/
static void
expandhere(union node *arg, int fd)
{
expandarg(arg, (struct arglist *)NULL, EXP_QUOTED);
full_write(fd, stackblock(), expdest - (char *)stackblock());
}
/*
* Returns true if the pattern matches the string.
*/
static int
patmatch(char *pattern, const char *string)
{
return pmatch(preglob(pattern, 0), string);
}
/*
* See if a pattern matches in a case statement.
*/
static int
casematch(union node *pattern, char *val)
{
struct stackmark smark;
int result;
setstackmark(&smark);
argbackq = pattern->narg.backquote;
STARTSTACKSTR(expdest);
argstr(pattern->narg.text, EXP_TILDE | EXP_CASE,
/* var_str_list: */ NULL);
STACKSTRNUL(expdest);
ifsfree();
result = patmatch(stackblock(), val);
popstackmark(&smark);
return result;
}
/* ============ find_command */
struct builtincmd {
const char *name;
int (*builtin)(int, char **) FAST_FUNC;
/* unsigned flags; */
};
#define IS_BUILTIN_SPECIAL(b) ((b)->name[0] & 1)
/* "regular" builtins always take precedence over commands,
* regardless of PATH=....%builtin... position */
#define IS_BUILTIN_REGULAR(b) ((b)->name[0] & 2)
#define IS_BUILTIN_ASSIGN(b) ((b)->name[0] & 4)
struct cmdentry {
smallint cmdtype; /* CMDxxx */
union param {
int index;
/* index >= 0 for commands without path (slashes) */
/* (TODO: what exactly does the value mean? PATH position?) */
/* index == -1 for commands with slashes */
/* index == (-2 - applet_no) for NOFORK applets */
const struct builtincmd *cmd;
struct funcnode *func;
} u;
};
/* values of cmdtype */
#define CMDUNKNOWN -1 /* no entry in table for command */
#define CMDNORMAL 0 /* command is an executable program */
#define CMDFUNCTION 1 /* command is a shell function */
#define CMDBUILTIN 2 /* command is a shell builtin */
/* action to find_command() */
#define DO_ERR 0x01 /* prints errors */
#define DO_ABS 0x02 /* checks absolute paths */
#define DO_NOFUNC 0x04 /* don't return shell functions, for command */
#define DO_ALTPATH 0x08 /* using alternate path */
#define DO_ALTBLTIN 0x20 /* %builtin in alt. path */
static void find_command(char *, struct cmdentry *, int, const char *);
/* ============ Hashing commands */
/*
* When commands are first encountered, they are entered in a hash table.
* This ensures that a full path search will not have to be done for them
* on each invocation.
*
* We should investigate converting to a linear search, even though that
* would make the command name "hash" a misnomer.
*/
struct tblentry {
struct tblentry *next; /* next entry in hash chain */
union param param; /* definition of builtin function */
smallint cmdtype; /* CMDxxx */
char rehash; /* if set, cd done since entry created */
char cmdname[1]; /* name of command */
};
static struct tblentry **cmdtable;
#define INIT_G_cmdtable() do { \
cmdtable = xzalloc(CMDTABLESIZE * sizeof(cmdtable[0])); \
} while (0)
static int builtinloc = -1; /* index in path of %builtin, or -1 */
static void
tryexec(IF_FEATURE_SH_STANDALONE(int applet_no,) char *cmd, char **argv, char **envp)
{
#if ENABLE_FEATURE_SH_STANDALONE
if (applet_no >= 0) {
if (APPLET_IS_NOEXEC(applet_no)) {
clearenv();
while (*envp)
putenv(*envp++);
run_applet_no_and_exit(applet_no, argv);
}
/* re-exec ourselves with the new arguments */
execve(bb_busybox_exec_path, argv, envp);
/* If they called chroot or otherwise made the binary no longer
* executable, fall through */
}
#endif
repeat:
#ifdef SYSV
do {
execve(cmd, argv, envp);
} while (errno == EINTR);
#else
execve(cmd, argv, envp);
#endif
if (cmd != (char*) bb_busybox_exec_path && errno == ENOEXEC) {
/* Run "cmd" as a shell script:
* http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html
* "If the execve() function fails with ENOEXEC, the shell
* shall execute a command equivalent to having a shell invoked
* with the command name as its first operand,
* with any remaining arguments passed to the new shell"
*
* That is, do not use $SHELL, user's shell, or /bin/sh;
* just call ourselves.
*
* Note that bash reads ~80 chars of the file, and if it sees
* a zero byte before it sees newline, it doesn't try to
* interpret it, but fails with "cannot execute binary file"
* message and exit code 126. For one, this prevents attempts
* to interpret foreign ELF binaries as shell scripts.
*/
argv[0] = cmd;
cmd = (char*) bb_busybox_exec_path;
/* NB: this is only possible because all callers of shellexec()
* ensure that the argv[-1] slot exists!
*/
argv--;
argv[0] = (char*) "ash";
goto repeat;
}
}
/*
* Exec a program. Never returns. If you change this routine, you may
* have to change the find_command routine as well.
* argv[-1] must exist and be writable! See tryexec() for why.
*/
static void shellexec(char **, const char *, int) NORETURN;
static void
shellexec(char **argv, const char *path, int idx)
{
char *cmdname;
int e;
char **envp;
int exerrno;
int applet_no = -1; /* used only by FEATURE_SH_STANDALONE */
envp = listvars(VEXPORT, VUNSET, /*end:*/ NULL);
if (strchr(argv[0], '/') != NULL
#if ENABLE_FEATURE_SH_STANDALONE
|| (applet_no = find_applet_by_name(argv[0])) >= 0
#endif
) {
tryexec(IF_FEATURE_SH_STANDALONE(applet_no,) argv[0], argv, envp);
if (applet_no >= 0) {
/* We tried execing ourself, but it didn't work.
* Maybe /proc/self/exe doesn't exist?
* Try $PATH search.
*/
goto try_PATH;
}
e = errno;
} else {
try_PATH:
e = ENOENT;
while ((cmdname = path_advance(&path, argv[0])) != NULL) {
if (--idx < 0 && pathopt == NULL) {
tryexec(IF_FEATURE_SH_STANDALONE(-1,) cmdname, argv, envp);
if (errno != ENOENT && errno != ENOTDIR)
e = errno;
}
stunalloc(cmdname);
}
}
/* Map to POSIX errors */
switch (e) {
case EACCES:
exerrno = 126;
break;
case ENOENT:
exerrno = 127;
break;
default:
exerrno = 2;
break;
}
exitstatus = exerrno;
TRACE(("shellexec failed for %s, errno %d, suppress_int %d\n",
argv[0], e, suppress_int));
ash_msg_and_raise(EXEXIT, "%s: %s", argv[0], errmsg(e, "not found"));
/* NOTREACHED */
}
static void
printentry(struct tblentry *cmdp)
{
int idx;
const char *path;
char *name;
idx = cmdp->param.index;
path = pathval();
do {
name = path_advance(&path, cmdp->cmdname);
stunalloc(name);
} while (--idx >= 0);
out1fmt("%s%s\n", name, (cmdp->rehash ? "*" : nullstr));
}
/*
* Clear out command entries. The argument specifies the first entry in
* PATH which has changed.
*/
static void
clearcmdentry(int firstchange)
{
struct tblentry **tblp;
struct tblentry **pp;
struct tblentry *cmdp;
INT_OFF;
for (tblp = cmdtable; tblp < &cmdtable[CMDTABLESIZE]; tblp++) {
pp = tblp;
while ((cmdp = *pp) != NULL) {
if ((cmdp->cmdtype == CMDNORMAL &&
cmdp->param.index >= firstchange)
|| (cmdp->cmdtype == CMDBUILTIN &&
builtinloc >= firstchange)
) {
*pp = cmdp->next;
free(cmdp);
} else {
pp = &cmdp->next;
}
}
}
INT_ON;
}
/*
* Locate a command in the command hash table. If "add" is nonzero,
* add the command to the table if it is not already present. The
* variable "lastcmdentry" is set to point to the address of the link
* pointing to the entry, so that delete_cmd_entry can delete the
* entry.
*
* Interrupts must be off if called with add != 0.
*/
static struct tblentry **lastcmdentry;
static struct tblentry *
cmdlookup(const char *name, int add)
{
unsigned int hashval;
const char *p;
struct tblentry *cmdp;
struct tblentry **pp;
p = name;
hashval = (unsigned char)*p << 4;
while (*p)
hashval += (unsigned char)*p++;
hashval &= 0x7FFF;
pp = &cmdtable[hashval % CMDTABLESIZE];
for (cmdp = *pp; cmdp; cmdp = cmdp->next) {
if (strcmp(cmdp->cmdname, name) == 0)
break;
pp = &cmdp->next;
}
if (add && cmdp == NULL) {
cmdp = *pp = ckzalloc(sizeof(struct tblentry)
+ strlen(name)
/* + 1 - already done because
* tblentry::cmdname is char[1] */);
/*cmdp->next = NULL; - ckzalloc did it */
cmdp->cmdtype = CMDUNKNOWN;
strcpy(cmdp->cmdname, name);
}
lastcmdentry = pp;
return cmdp;
}
/*
* Delete the command entry returned on the last lookup.
*/
static void
delete_cmd_entry(void)
{
struct tblentry *cmdp;
INT_OFF;
cmdp = *lastcmdentry;
*lastcmdentry = cmdp->next;
if (cmdp->cmdtype == CMDFUNCTION)
freefunc(cmdp->param.func);
free(cmdp);
INT_ON;
}
/*
* Add a new command entry, replacing any existing command entry for
* the same name - except special builtins.
*/
static void
addcmdentry(char *name, struct cmdentry *entry)
{
struct tblentry *cmdp;
cmdp = cmdlookup(name, 1);
if (cmdp->cmdtype == CMDFUNCTION) {
freefunc(cmdp->param.func);
}
cmdp->cmdtype = entry->cmdtype;
cmdp->param = entry->u;
cmdp->rehash = 0;
}
static int FAST_FUNC
hashcmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
struct tblentry **pp;
struct tblentry *cmdp;
int c;
struct cmdentry entry;
char *name;
if (nextopt("r") != '\0') {
clearcmdentry(0);
return 0;
}
if (*argptr == NULL) {
for (pp = cmdtable; pp < &cmdtable[CMDTABLESIZE]; pp++) {
for (cmdp = *pp; cmdp; cmdp = cmdp->next) {
if (cmdp->cmdtype == CMDNORMAL)
printentry(cmdp);
}
}
return 0;
}
c = 0;
while ((name = *argptr) != NULL) {
cmdp = cmdlookup(name, 0);
if (cmdp != NULL
&& (cmdp->cmdtype == CMDNORMAL
|| (cmdp->cmdtype == CMDBUILTIN && builtinloc >= 0))
) {
delete_cmd_entry();
}
find_command(name, &entry, DO_ERR, pathval());
if (entry.cmdtype == CMDUNKNOWN)
c = 1;
argptr++;
}
return c;
}
/*
* Called when a cd is done. Marks all commands so the next time they
* are executed they will be rehashed.
*/
static void
hashcd(void)
{
struct tblentry **pp;
struct tblentry *cmdp;
for (pp = cmdtable; pp < &cmdtable[CMDTABLESIZE]; pp++) {
for (cmdp = *pp; cmdp; cmdp = cmdp->next) {
if (cmdp->cmdtype == CMDNORMAL
|| (cmdp->cmdtype == CMDBUILTIN
&& !IS_BUILTIN_REGULAR(cmdp->param.cmd)
&& builtinloc > 0)
) {
cmdp->rehash = 1;
}
}
}
}
/*
* Fix command hash table when PATH changed.
* Called before PATH is changed. The argument is the new value of PATH;
* pathval() still returns the old value at this point.
* Called with interrupts off.
*/
static void FAST_FUNC
changepath(const char *new)
{
const char *old;
int firstchange;
int idx;
int idx_bltin;
old = pathval();
firstchange = 9999; /* assume no change */
idx = 0;
idx_bltin = -1;
for (;;) {
if (*old != *new) {
firstchange = idx;
if ((*old == '\0' && *new == ':')
|| (*old == ':' && *new == '\0')
) {
firstchange++;
}
old = new; /* ignore subsequent differences */
}
if (*new == '\0')
break;
if (*new == '%' && idx_bltin < 0 && prefix(new + 1, "builtin"))
idx_bltin = idx;
if (*new == ':')
idx++;
new++;
old++;
}
if (builtinloc < 0 && idx_bltin >= 0)
builtinloc = idx_bltin; /* zap builtins */
if (builtinloc >= 0 && idx_bltin < 0)
firstchange = 0;
clearcmdentry(firstchange);
builtinloc = idx_bltin;
}
enum {
TEOF,
TNL,
TREDIR,
TWORD,
TSEMI,
TBACKGND,
TAND,
TOR,
TPIPE,
TLP,
TRP,
TENDCASE,
TENDBQUOTE,
TNOT,
TCASE,
TDO,
TDONE,
TELIF,
TELSE,
TESAC,
TFI,
TFOR,
#if ENABLE_ASH_BASH_COMPAT
TFUNCTION,
#endif
TIF,
TIN,
TTHEN,
TUNTIL,
TWHILE,
TBEGIN,
TEND
};
typedef smallint token_id_t;
/* Nth bit indicates if token marks the end of a list */
enum {
tokendlist = 0
/* 0 */ | (1u << TEOF)
/* 1 */ | (0u << TNL)
/* 2 */ | (0u << TREDIR)
/* 3 */ | (0u << TWORD)
/* 4 */ | (0u << TSEMI)
/* 5 */ | (0u << TBACKGND)
/* 6 */ | (0u << TAND)
/* 7 */ | (0u << TOR)
/* 8 */ | (0u << TPIPE)
/* 9 */ | (0u << TLP)
/* 10 */ | (1u << TRP)
/* 11 */ | (1u << TENDCASE)
/* 12 */ | (1u << TENDBQUOTE)
/* 13 */ | (0u << TNOT)
/* 14 */ | (0u << TCASE)
/* 15 */ | (1u << TDO)
/* 16 */ | (1u << TDONE)
/* 17 */ | (1u << TELIF)
/* 18 */ | (1u << TELSE)
/* 19 */ | (1u << TESAC)
/* 20 */ | (1u << TFI)
/* 21 */ | (0u << TFOR)
#if ENABLE_ASH_BASH_COMPAT
/* 22 */ | (0u << TFUNCTION)
#endif
/* 23 */ | (0u << TIF)
/* 24 */ | (0u << TIN)
/* 25 */ | (1u << TTHEN)
/* 26 */ | (0u << TUNTIL)
/* 27 */ | (0u << TWHILE)
/* 28 */ | (0u << TBEGIN)
/* 29 */ | (1u << TEND)
, /* thus far 29 bits used */
};
static const char *const tokname_array[] = {
"end of file",
"newline",
"redirection",
"word",
";",
"&",
"&&",
"||",
"|",
"(",
")",
";;",
"`",
#define KWDOFFSET 13
/* the following are keywords */
"!",
"case",
"do",
"done",
"elif",
"else",
"esac",
"fi",
"for",
#if ENABLE_ASH_BASH_COMPAT
"function",
#endif
"if",
"in",
"then",
"until",
"while",
"{",
"}",
};
/* Wrapper around strcmp for qsort/bsearch/... */
static int
pstrcmp(const void *a, const void *b)
{
return strcmp((char*)a, *(char**)b);
}
static const char *const *
findkwd(const char *s)
{
return bsearch(s, tokname_array + KWDOFFSET,
ARRAY_SIZE(tokname_array) - KWDOFFSET,
sizeof(tokname_array[0]), pstrcmp);
}
/*
* Locate and print what a word is...
*/
static int
describe_command(char *command, const char *path, int describe_command_verbose)
{
struct cmdentry entry;
struct tblentry *cmdp;
#if ENABLE_ASH_ALIAS
const struct alias *ap;
#endif
path = path ? path : pathval();
if (describe_command_verbose) {
out1str(command);
}
/* First look at the keywords */
if (findkwd(command)) {
out1str(describe_command_verbose ? " is a shell keyword" : command);
goto out;
}
#if ENABLE_ASH_ALIAS
/* Then look at the aliases */
ap = lookupalias(command, 0);
if (ap != NULL) {
if (!describe_command_verbose) {
out1str("alias ");
printalias(ap);
return 0;
}
out1fmt(" is an alias for %s", ap->val);
goto out;
}
#endif
/* Then check if it is a tracked alias */
cmdp = cmdlookup(command, 0);
if (cmdp != NULL) {
entry.cmdtype = cmdp->cmdtype;
entry.u = cmdp->param;
} else {
/* Finally use brute force */
find_command(command, &entry, DO_ABS, path);
}
switch (entry.cmdtype) {
case CMDNORMAL: {
int j = entry.u.index;
char *p;
if (j < 0) {
p = command;
} else {
do {
p = path_advance(&path, command);
stunalloc(p);
} while (--j >= 0);
}
if (describe_command_verbose) {
out1fmt(" is%s %s",
(cmdp ? " a tracked alias for" : nullstr), p
);
} else {
out1str(p);
}
break;
}
case CMDFUNCTION:
if (describe_command_verbose) {
out1str(" is a shell function");
} else {
out1str(command);
}
break;
case CMDBUILTIN:
if (describe_command_verbose) {
out1fmt(" is a %sshell builtin",
IS_BUILTIN_SPECIAL(entry.u.cmd) ?
"special " : nullstr
);
} else {
out1str(command);
}
break;
default:
if (describe_command_verbose) {
out1str(": not found\n");
}
return 127;
}
out:
out1str("\n");
return 0;
}
static int FAST_FUNC
typecmd(int argc UNUSED_PARAM, char **argv)
{
int i = 1;
int err = 0;
int verbose = 1;
/* type -p ... ? (we don't bother checking for 'p') */
if (argv[1] && argv[1][0] == '-') {
i++;
verbose = 0;
}
while (argv[i]) {
err |= describe_command(argv[i++], NULL, verbose);
}
return err;
}
#if ENABLE_ASH_CMDCMD
/* Is it "command [-p] PROG ARGS" bltin, no other opts? Return ptr to "PROG" if yes */
static char **
parse_command_args(char **argv, const char **path)
{
char *cp, c;
for (;;) {
cp = *++argv;
if (!cp)
return NULL;
if (*cp++ != '-')
break;
c = *cp++;
if (!c)
break;
if (c == '-' && !*cp) {
if (!*++argv)
return NULL;
break;
}
do {
switch (c) {
case 'p':
*path = bb_default_path;
break;
default:
/* run 'typecmd' for other options */
return NULL;
}
c = *cp++;
} while (c);
}
return argv;
}
static int FAST_FUNC
commandcmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
char *cmd;
int c;
enum {
VERIFY_BRIEF = 1,
VERIFY_VERBOSE = 2,
} verify = 0;
const char *path = NULL;
/* "command [-p] PROG ARGS" (that is, without -V or -v)
* never reaches this function.
*/
while ((c = nextopt("pvV")) != '\0')
if (c == 'V')
verify |= VERIFY_VERBOSE;
else if (c == 'v')
/*verify |= VERIFY_BRIEF*/;
#if DEBUG
else if (c != 'p')
abort();
#endif
else
path = bb_default_path;
/* Mimic bash: just "command -v" doesn't complain, it's a nop */
cmd = *argptr;
if (/*verify && */ cmd)
return describe_command(cmd, path, verify /* - VERIFY_BRIEF*/);
return 0;
}
#endif
/*static int funcblocksize; // size of structures in function */
/*static int funcstringsize; // size of strings in node */
static void *funcblock; /* block to allocate function from */
static char *funcstring_end; /* end of block to allocate strings from */
/* flags in argument to evaltree */
#define EV_EXIT 01 /* exit after evaluating tree */
#define EV_TESTED 02 /* exit status is checked; ignore -e flag */
static const uint8_t nodesize[N_NUMBER] ALIGN1 = {
[NCMD ] = SHELL_ALIGN(sizeof(struct ncmd)),
[NPIPE ] = SHELL_ALIGN(sizeof(struct npipe)),
[NREDIR ] = SHELL_ALIGN(sizeof(struct nredir)),
[NBACKGND ] = SHELL_ALIGN(sizeof(struct nredir)),
[NSUBSHELL] = SHELL_ALIGN(sizeof(struct nredir)),
[NAND ] = SHELL_ALIGN(sizeof(struct nbinary)),
[NOR ] = SHELL_ALIGN(sizeof(struct nbinary)),
[NSEMI ] = SHELL_ALIGN(sizeof(struct nbinary)),
[NIF ] = SHELL_ALIGN(sizeof(struct nif)),
[NWHILE ] = SHELL_ALIGN(sizeof(struct nbinary)),
[NUNTIL ] = SHELL_ALIGN(sizeof(struct nbinary)),
[NFOR ] = SHELL_ALIGN(sizeof(struct nfor)),
[NCASE ] = SHELL_ALIGN(sizeof(struct ncase)),
[NCLIST ] = SHELL_ALIGN(sizeof(struct nclist)),
[NDEFUN ] = SHELL_ALIGN(sizeof(struct narg)),
[NARG ] = SHELL_ALIGN(sizeof(struct narg)),
[NTO ] = SHELL_ALIGN(sizeof(struct nfile)),
#if ENABLE_ASH_BASH_COMPAT
[NTO2 ] = SHELL_ALIGN(sizeof(struct nfile)),
#endif
[NCLOBBER ] = SHELL_ALIGN(sizeof(struct nfile)),
[NFROM ] = SHELL_ALIGN(sizeof(struct nfile)),
[NFROMTO ] = SHELL_ALIGN(sizeof(struct nfile)),
[NAPPEND ] = SHELL_ALIGN(sizeof(struct nfile)),
[NTOFD ] = SHELL_ALIGN(sizeof(struct ndup)),
[NFROMFD ] = SHELL_ALIGN(sizeof(struct ndup)),
[NHERE ] = SHELL_ALIGN(sizeof(struct nhere)),
[NXHERE ] = SHELL_ALIGN(sizeof(struct nhere)),
[NNOT ] = SHELL_ALIGN(sizeof(struct nnot)),
};
static int calcsize(int funcblocksize, union node *n);
static int
sizenodelist(int funcblocksize, struct nodelist *lp)
{
while (lp) {
funcblocksize += SHELL_ALIGN(sizeof(struct nodelist));
funcblocksize = calcsize(funcblocksize, lp->n);
lp = lp->next;
}
return funcblocksize;
}
static int
calcsize(int funcblocksize, union node *n)
{
if (n == NULL)
return funcblocksize;
funcblocksize += nodesize[n->type];
switch (n->type) {
case NCMD:
funcblocksize = calcsize(funcblocksize, n->ncmd.redirect);
funcblocksize = calcsize(funcblocksize, n->ncmd.args);
funcblocksize = calcsize(funcblocksize, n->ncmd.assign);
break;
case NPIPE:
funcblocksize = sizenodelist(funcblocksize, n->npipe.cmdlist);
break;
case NREDIR:
case NBACKGND:
case NSUBSHELL:
funcblocksize = calcsize(funcblocksize, n->nredir.redirect);
funcblocksize = calcsize(funcblocksize, n->nredir.n);
break;
case NAND:
case NOR:
case NSEMI:
case NWHILE:
case NUNTIL:
funcblocksize = calcsize(funcblocksize, n->nbinary.ch2);
funcblocksize = calcsize(funcblocksize, n->nbinary.ch1);
break;
case NIF:
funcblocksize = calcsize(funcblocksize, n->nif.elsepart);
funcblocksize = calcsize(funcblocksize, n->nif.ifpart);
funcblocksize = calcsize(funcblocksize, n->nif.test);
break;
case NFOR:
funcblocksize += SHELL_ALIGN(strlen(n->nfor.var) + 1); /* was funcstringsize += ... */
funcblocksize = calcsize(funcblocksize, n->nfor.body);
funcblocksize = calcsize(funcblocksize, n->nfor.args);
break;
case NCASE:
funcblocksize = calcsize(funcblocksize, n->ncase.cases);
funcblocksize = calcsize(funcblocksize, n->ncase.expr);
break;
case NCLIST:
funcblocksize = calcsize(funcblocksize, n->nclist.body);
funcblocksize = calcsize(funcblocksize, n->nclist.pattern);
funcblocksize = calcsize(funcblocksize, n->nclist.next);
break;
case NDEFUN:
case NARG:
funcblocksize = sizenodelist(funcblocksize, n->narg.backquote);
funcblocksize += SHELL_ALIGN(strlen(n->narg.text) + 1); /* was funcstringsize += ... */
funcblocksize = calcsize(funcblocksize, n->narg.next);
break;
case NTO:
#if ENABLE_ASH_BASH_COMPAT
case NTO2:
#endif
case NCLOBBER:
case NFROM:
case NFROMTO:
case NAPPEND:
funcblocksize = calcsize(funcblocksize, n->nfile.fname);
funcblocksize = calcsize(funcblocksize, n->nfile.next);
break;
case NTOFD:
case NFROMFD:
funcblocksize = calcsize(funcblocksize, n->ndup.vname);
funcblocksize = calcsize(funcblocksize, n->ndup.next);
break;
case NHERE:
case NXHERE:
funcblocksize = calcsize(funcblocksize, n->nhere.doc);
funcblocksize = calcsize(funcblocksize, n->nhere.next);
break;
case NNOT:
funcblocksize = calcsize(funcblocksize, n->nnot.com);
break;
};
return funcblocksize;
}
static char *
nodeckstrdup(char *s)
{
funcstring_end -= SHELL_ALIGN(strlen(s) + 1);
return strcpy(funcstring_end, s);
}
static union node *copynode(union node *);
static struct nodelist *
copynodelist(struct nodelist *lp)
{
struct nodelist *start;
struct nodelist **lpp;
lpp = &start;
while (lp) {
*lpp = funcblock;
funcblock = (char *) funcblock + SHELL_ALIGN(sizeof(struct nodelist));
(*lpp)->n = copynode(lp->n);
lp = lp->next;
lpp = &(*lpp)->next;
}
*lpp = NULL;
return start;
}
static union node *
copynode(union node *n)
{
union node *new;
if (n == NULL)
return NULL;
new = funcblock;
funcblock = (char *) funcblock + nodesize[n->type];
switch (n->type) {
case NCMD:
new->ncmd.redirect = copynode(n->ncmd.redirect);
new->ncmd.args = copynode(n->ncmd.args);
new->ncmd.assign = copynode(n->ncmd.assign);
break;
case NPIPE:
new->npipe.cmdlist = copynodelist(n->npipe.cmdlist);
new->npipe.pipe_backgnd = n->npipe.pipe_backgnd;
break;
case NREDIR:
case NBACKGND:
case NSUBSHELL:
new->nredir.redirect = copynode(n->nredir.redirect);
new->nredir.n = copynode(n->nredir.n);
break;
case NAND:
case NOR:
case NSEMI:
case NWHILE:
case NUNTIL:
new->nbinary.ch2 = copynode(n->nbinary.ch2);
new->nbinary.ch1 = copynode(n->nbinary.ch1);
break;
case NIF:
new->nif.elsepart = copynode(n->nif.elsepart);
new->nif.ifpart = copynode(n->nif.ifpart);
new->nif.test = copynode(n->nif.test);
break;
case NFOR:
new->nfor.var = nodeckstrdup(n->nfor.var);
new->nfor.body = copynode(n->nfor.body);
new->nfor.args = copynode(n->nfor.args);
break;
case NCASE:
new->ncase.cases = copynode(n->ncase.cases);
new->ncase.expr = copynode(n->ncase.expr);
break;
case NCLIST:
new->nclist.body = copynode(n->nclist.body);
new->nclist.pattern = copynode(n->nclist.pattern);
new->nclist.next = copynode(n->nclist.next);
break;
case NDEFUN:
case NARG:
new->narg.backquote = copynodelist(n->narg.backquote);
new->narg.text = nodeckstrdup(n->narg.text);
new->narg.next = copynode(n->narg.next);
break;
case NTO:
#if ENABLE_ASH_BASH_COMPAT
case NTO2:
#endif
case NCLOBBER:
case NFROM:
case NFROMTO:
case NAPPEND:
new->nfile.fname = copynode(n->nfile.fname);
new->nfile.fd = n->nfile.fd;
new->nfile.next = copynode(n->nfile.next);
break;
case NTOFD:
case NFROMFD:
new->ndup.vname = copynode(n->ndup.vname);
new->ndup.dupfd = n->ndup.dupfd;
new->ndup.fd = n->ndup.fd;
new->ndup.next = copynode(n->ndup.next);
break;
case NHERE:
case NXHERE:
new->nhere.doc = copynode(n->nhere.doc);
new->nhere.fd = n->nhere.fd;
new->nhere.next = copynode(n->nhere.next);
break;
case NNOT:
new->nnot.com = copynode(n->nnot.com);
break;
};
new->type = n->type;
return new;
}
/*
* Make a copy of a parse tree.
*/
static struct funcnode *
copyfunc(union node *n)
{
struct funcnode *f;
size_t blocksize;
/*funcstringsize = 0;*/
blocksize = offsetof(struct funcnode, n) + calcsize(0, n);
f = ckzalloc(blocksize /* + funcstringsize */);
funcblock = (char *) f + offsetof(struct funcnode, n);
funcstring_end = (char *) f + blocksize;
copynode(n);
/* f->count = 0; - ckzalloc did it */
return f;
}
/*
* Define a shell function.
*/
static void
defun(union node *func)
{
struct cmdentry entry;
INT_OFF;
entry.cmdtype = CMDFUNCTION;
entry.u.func = copyfunc(func);
addcmdentry(func->narg.text, &entry);
INT_ON;
}
/* Reasons for skipping commands (see comment on breakcmd routine) */
#define SKIPBREAK (1 << 0)
#define SKIPCONT (1 << 1)
#define SKIPFUNC (1 << 2)
static smallint evalskip; /* set to SKIPxxx if we are skipping commands */
static int skipcount; /* number of levels to skip */
static int funcnest; /* depth of function calls */
static int loopnest; /* current loop nesting level */
/* Forward decl way out to parsing code - dotrap needs it */
static int evalstring(char *s, int flags);
/* Called to execute a trap.
* Single callsite - at the end of evaltree().
* If we return non-zero, evaltree raises EXEXIT exception.
*
* Perhaps we should avoid entering new trap handlers
* while we are executing a trap handler. [is it a TODO?]
*/
static void
dotrap(void)
{
uint8_t *g;
int sig;
uint8_t last_status;
if (!pending_sig)
return;
last_status = exitstatus;
pending_sig = 0;
barrier();
TRACE(("dotrap entered\n"));
for (sig = 1, g = gotsig; sig < NSIG; sig++, g++) {
char *p;
if (!*g)
continue;
if (evalskip) {
pending_sig = sig;
break;
}
p = trap[sig];
/* non-trapped SIGINT is handled separately by raise_interrupt,
* don't upset it by resetting gotsig[SIGINT-1] */
if (sig == SIGINT && !p)
continue;
TRACE(("sig %d is active, will run handler '%s'\n", sig, p));
*g = 0;
if (!p)
continue;
evalstring(p, 0);
}
exitstatus = last_status;
TRACE(("dotrap returns\n"));
}
/* forward declarations - evaluation is fairly recursive business... */
static int evalloop(union node *, int);
static int evalfor(union node *, int);
static int evalcase(union node *, int);
static int evalsubshell(union node *, int);
static void expredir(union node *);
static int evalpipe(union node *, int);
static int evalcommand(union node *, int);
static int evalbltin(const struct builtincmd *, int, char **, int);
static void prehash(union node *);
/*
* Evaluate a parse tree. The value is left in the global variable
* exitstatus.
*/
static int
evaltree(union node *n, int flags)
{
int checkexit = 0;
int (*evalfn)(union node *, int);
int status = 0;
if (n == NULL) {
TRACE(("evaltree(NULL) called\n"));
goto out;
}
TRACE(("evaltree(%p: %d, %d) called\n", n, n->type, flags));
dotrap();
switch (n->type) {
default:
#if DEBUG
out1fmt("Node type = %d\n", n->type);
fflush_all();
break;
#endif
case NNOT:
status = !evaltree(n->nnot.com, EV_TESTED);
goto setstatus;
case NREDIR:
expredir(n->nredir.redirect);
status = redirectsafe(n->nredir.redirect, REDIR_PUSH);
if (!status) {
status = evaltree(n->nredir.n, flags & EV_TESTED);
}
if (n->nredir.redirect)
popredir(/*drop:*/ 0, /*restore:*/ 0 /* not sure */);
goto setstatus;
case NCMD:
evalfn = evalcommand;
checkexit:
if (eflag && !(flags & EV_TESTED))
checkexit = ~0;
goto calleval;
case NFOR:
evalfn = evalfor;
goto calleval;
case NWHILE:
case NUNTIL:
evalfn = evalloop;
goto calleval;
case NSUBSHELL:
case NBACKGND:
evalfn = evalsubshell;
goto checkexit;
case NPIPE:
evalfn = evalpipe;
goto checkexit;
case NCASE:
evalfn = evalcase;
goto calleval;
case NAND:
case NOR:
case NSEMI: {
#if NAND + 1 != NOR
#error NAND + 1 != NOR
#endif
#if NOR + 1 != NSEMI
#error NOR + 1 != NSEMI
#endif
unsigned is_or = n->type - NAND;
status = evaltree(
n->nbinary.ch1,
(flags | ((is_or >> 1) - 1)) & EV_TESTED
);
if ((!status) == is_or || evalskip)
break;
n = n->nbinary.ch2;
evaln:
evalfn = evaltree;
calleval:
status = evalfn(n, flags);
goto setstatus;
}
case NIF:
status = evaltree(n->nif.test, EV_TESTED);
if (evalskip)
break;
if (!status) {
n = n->nif.ifpart;
goto evaln;
}
if (n->nif.elsepart) {
n = n->nif.elsepart;
goto evaln;
}
status = 0;
goto setstatus;
case NDEFUN:
defun(n);
/* Not necessary. To test it:
* "false; f() { qwerty; }; echo $?" should print 0.
*/
/* status = 0; */
setstatus:
exitstatus = status;
break;
}
out:
/* Order of checks below is important:
* signal handlers trigger before exit caused by "set -e".
*/
dotrap();
if (checkexit & status)
raise_exception(EXEXIT);
if (flags & EV_EXIT)
raise_exception(EXEXIT);
TRACE(("leaving evaltree (no interrupts)\n"));
return exitstatus;
}
#if !defined(__alpha__) || (defined(__GNUC__) && __GNUC__ >= 3)
static
#endif
int evaltreenr(union node *, int) __attribute__ ((alias("evaltree"),__noreturn__));
static int
skiploop(void)
{
int skip = evalskip;
switch (skip) {
case 0:
break;
case SKIPBREAK:
case SKIPCONT:
if (--skipcount <= 0) {
evalskip = 0;
break;
}
skip = SKIPBREAK;
break;
}
return skip;
}
static int
evalloop(union node *n, int flags)
{
int skip;
int status;
loopnest++;
status = 0;
flags &= EV_TESTED;
do {
int i;
i = evaltree(n->nbinary.ch1, EV_TESTED);
skip = skiploop();
if (skip == SKIPFUNC)
status = i;
if (skip)
continue;
if (n->type != NWHILE)
i = !i;
if (i != 0)
break;
status = evaltree(n->nbinary.ch2, flags);
skip = skiploop();
} while (!(skip & ~SKIPCONT));
loopnest--;
return status;
}
static int
evalfor(union node *n, int flags)
{
struct arglist arglist;
union node *argp;
struct strlist *sp;
struct stackmark smark;
int status = 0;
setstackmark(&smark);
arglist.list = NULL;
arglist.lastp = &arglist.list;
for (argp = n->nfor.args; argp; argp = argp->narg.next) {
expandarg(argp, &arglist, EXP_FULL | EXP_TILDE);
}
*arglist.lastp = NULL;
loopnest++;
flags &= EV_TESTED;
for (sp = arglist.list; sp; sp = sp->next) {
setvar0(n->nfor.var, sp->text);
status = evaltree(n->nfor.body, flags);
if (skiploop() & ~SKIPCONT)
break;
}
loopnest--;
popstackmark(&smark);
return status;
}
static int
evalcase(union node *n, int flags)
{
union node *cp;
union node *patp;
struct arglist arglist;
struct stackmark smark;
int status = 0;
setstackmark(&smark);
arglist.list = NULL;
arglist.lastp = &arglist.list;
expandarg(n->ncase.expr, &arglist, EXP_TILDE);
for (cp = n->ncase.cases; cp && evalskip == 0; cp = cp->nclist.next) {
for (patp = cp->nclist.pattern; patp; patp = patp->narg.next) {
if (casematch(patp, arglist.list->text)) {
/* Ensure body is non-empty as otherwise
* EV_EXIT may prevent us from setting the
* exit status.
*/
if (evalskip == 0 && cp->nclist.body) {
status = evaltree(cp->nclist.body, flags);
}
goto out;
}
}
}
out:
popstackmark(&smark);
return status;
}
/*
* Kick off a subshell to evaluate a tree.
*/
static int
evalsubshell(union node *n, int flags)
{
struct job *jp;
int backgnd = (n->type == NBACKGND);
int status;
expredir(n->nredir.redirect);
if (!backgnd && (flags & EV_EXIT) && !may_have_traps)
goto nofork;
INT_OFF;
jp = makejob(/*n,*/ 1);
if (forkshell(jp, n, backgnd) == 0) {
/* child */
INT_ON;
flags |= EV_EXIT;
if (backgnd)
flags &= ~EV_TESTED;
nofork:
redirect(n->nredir.redirect, 0);
evaltreenr(n->nredir.n, flags);
/* never returns */
}
/* parent */
status = 0;
if (!backgnd)
status = waitforjob(jp);
INT_ON;
return status;
}
/*
* Compute the names of the files in a redirection list.
*/
static void fixredir(union node *, const char *, int);
static void
expredir(union node *n)
{
union node *redir;
for (redir = n; redir; redir = redir->nfile.next) {
struct arglist fn;
fn.list = NULL;
fn.lastp = &fn.list;
switch (redir->type) {
case NFROMTO:
case NFROM:
case NTO:
#if ENABLE_ASH_BASH_COMPAT
case NTO2:
#endif
case NCLOBBER:
case NAPPEND:
expandarg(redir->nfile.fname, &fn, EXP_TILDE | EXP_REDIR);
TRACE(("expredir expanded to '%s'\n", fn.list->text));
#if ENABLE_ASH_BASH_COMPAT
store_expfname:
#endif
#if 0
// By the design of stack allocator, the loop of this kind:
// while true; do while true; do break; done </dev/null; done
// will look like a memory leak: ash plans to free expfname's
// of "/dev/null" as soon as it finishes running the loop
// (in this case, never).
// This "fix" is wrong:
if (redir->nfile.expfname)
stunalloc(redir->nfile.expfname);
// It results in corrupted state of stacked allocations.
#endif
redir->nfile.expfname = fn.list->text;
break;
case NFROMFD:
case NTOFD: /* >& */
if (redir->ndup.vname) {
expandarg(redir->ndup.vname, &fn, EXP_FULL | EXP_TILDE);
if (fn.list == NULL)
ash_msg_and_raise_error("redir error");
#if ENABLE_ASH_BASH_COMPAT
//FIXME: we used expandarg with different args!
if (!isdigit_str9(fn.list->text)) {
/* >&file, not >&fd */
if (redir->nfile.fd != 1) /* 123>&file - BAD */
ash_msg_and_raise_error("redir error");
redir->type = NTO2;
goto store_expfname;
}
#endif
fixredir(redir, fn.list->text, 1);
}
break;
}
}
}
/*
* Evaluate a pipeline. All the processes in the pipeline are children
* of the process creating the pipeline. (This differs from some versions
* of the shell, which make the last process in a pipeline the parent
* of all the rest.)
*/
static int
evalpipe(union node *n, int flags)
{
struct job *jp;
struct nodelist *lp;
int pipelen;
int prevfd;
int pip[2];
int status = 0;
TRACE(("evalpipe(0x%lx) called\n", (long)n));
pipelen = 0;
for (lp = n->npipe.cmdlist; lp; lp = lp->next)
pipelen++;
flags |= EV_EXIT;
INT_OFF;
jp = makejob(/*n,*/ pipelen);
prevfd = -1;
for (lp = n->npipe.cmdlist; lp; lp = lp->next) {
prehash(lp->n);
pip[1] = -1;
if (lp->next) {
if (pipe(pip) < 0) {
close(prevfd);
ash_msg_and_raise_error("pipe call failed");
}
}
if (forkshell(jp, lp->n, n->npipe.pipe_backgnd) == 0) {
/* child */
INT_ON;
if (pip[1] >= 0) {
close(pip[0]);
}
if (prevfd > 0) {
dup2(prevfd, 0);
close(prevfd);
}
if (pip[1] > 1) {
dup2(pip[1], 1);
close(pip[1]);
}
evaltreenr(lp->n, flags);
/* never returns */
}
/* parent */
if (prevfd >= 0)
close(prevfd);
prevfd = pip[0];
/* Don't want to trigger debugging */
if (pip[1] != -1)
close(pip[1]);
}
if (n->npipe.pipe_backgnd == 0) {
status = waitforjob(jp);
TRACE(("evalpipe: job done exit status %d\n", status));
}
INT_ON;
return status;
}
/*
* Controls whether the shell is interactive or not.
*/
static void
setinteractive(int on)
{
static smallint is_interactive;
if (++on == is_interactive)
return;
is_interactive = on;
setsignal(SIGINT);
setsignal(SIGQUIT);
setsignal(SIGTERM);
#if !ENABLE_FEATURE_SH_EXTRA_QUIET
if (is_interactive > 1) {
/* Looks like they want an interactive shell */
static smallint did_banner;
if (!did_banner) {
/* note: ash and hush share this string */
out1fmt("\n\n%s %s\n"
IF_ASH_HELP("Enter 'help' for a list of built-in commands.\n")
"\n",
bb_banner,
"built-in shell (ash)"
);
did_banner = 1;
}
}
#endif
}
static void
optschanged(void)
{
#if DEBUG
opentrace();
#endif
setinteractive(iflag);
setjobctl(mflag);
#if ENABLE_FEATURE_EDITING_VI
if (viflag)
line_input_state->flags |= VI_MODE;
else
line_input_state->flags &= ~VI_MODE;
#else
viflag = 0; /* forcibly keep the option off */
#endif
}
static struct localvar *localvars;
/*
* Called after a function returns.
* Interrupts must be off.
*/
static void
poplocalvars(void)
{
struct localvar *lvp;
struct var *vp;
while ((lvp = localvars) != NULL) {
localvars = lvp->next;
vp = lvp->vp;
TRACE(("poplocalvar %s\n", vp ? vp->var_text : "-"));
if (vp == NULL) { /* $- saved */
memcpy(optlist, lvp->text, sizeof(optlist));
free((char*)lvp->text);
optschanged();
} else if ((lvp->flags & (VUNSET|VSTRFIXED)) == VUNSET) {
unsetvar(vp->var_text);
} else {
if (vp->var_func)
vp->var_func(var_end(lvp->text));
if ((vp->flags & (VTEXTFIXED|VSTACK)) == 0)
free((char*)vp->var_text);
vp->flags = lvp->flags;
vp->var_text = lvp->text;
}
free(lvp);
}
}
static int
evalfun(struct funcnode *func, int argc, char **argv, int flags)
{
volatile struct shparam saveparam;
struct localvar *volatile savelocalvars;
struct jmploc *volatile savehandler;
struct jmploc jmploc;
int e;
saveparam = shellparam;
savelocalvars = localvars;
savehandler = exception_handler;
e = setjmp(jmploc.loc);
if (e) {
goto funcdone;
}
INT_OFF;
exception_handler = &jmploc;
localvars = NULL;
shellparam.malloced = 0;
func->count++;
funcnest++;
INT_ON;
shellparam.nparam = argc - 1;
shellparam.p = argv + 1;
#if ENABLE_ASH_GETOPTS
shellparam.optind = 1;
shellparam.optoff = -1;
#endif
evaltree(func->n.narg.next, flags & EV_TESTED);
funcdone:
INT_OFF;
funcnest--;
freefunc(func);
poplocalvars();
localvars = savelocalvars;
freeparam(&shellparam);
shellparam = saveparam;
exception_handler = savehandler;
INT_ON;
evalskip &= ~SKIPFUNC;
return e;
}
/*
* Make a variable a local variable. When a variable is made local, it's
* value and flags are saved in a localvar structure. The saved values
* will be restored when the shell function returns. We handle the name
* "-" as a special case: it makes changes to "set +-options" local
* (options will be restored on return from the function).
*/
static void
mklocal(char *name)
{
struct localvar *lvp;
struct var **vpp;
struct var *vp;
char *eq = strchr(name, '=');
INT_OFF;
/* Cater for duplicate "local". Examples:
* x=0; f() { local x=1; echo $x; local x; echo $x; }; f; echo $x
* x=0; f() { local x=1; echo $x; local x=2; echo $x; }; f; echo $x
*/
lvp = localvars;
while (lvp) {
if (lvp->vp && varcmp(lvp->vp->var_text, name) == 0) {
if (eq)
setvareq(name, 0);
/* else:
* it's a duplicate "local VAR" declaration, do nothing
*/
goto ret;
}
lvp = lvp->next;
}
lvp = ckzalloc(sizeof(*lvp));
if (LONE_DASH(name)) {
char *p;
p = ckmalloc(sizeof(optlist));
lvp->text = memcpy(p, optlist, sizeof(optlist));
vp = NULL;
} else {
vpp = hashvar(name);
vp = *findvar(vpp, name);
if (vp == NULL) {
/* variable did not exist yet */
if (eq)
setvareq(name, VSTRFIXED);
else
setvar(name, NULL, VSTRFIXED);
vp = *vpp; /* the new variable */
lvp->flags = VUNSET;
} else {
lvp->text = vp->var_text;
lvp->flags = vp->flags;
/* make sure neither "struct var" nor string gets freed
* during (un)setting:
*/
vp->flags |= VSTRFIXED|VTEXTFIXED;
if (eq)
setvareq(name, 0);
else
/* "local VAR" unsets VAR: */
setvar0(name, NULL);
}
}
lvp->vp = vp;
lvp->next = localvars;
localvars = lvp;
ret:
INT_ON;
}
/*
* The "local" command.
*/
static int FAST_FUNC
localcmd(int argc UNUSED_PARAM, char **argv)
{
char *name;
if (!funcnest)
ash_msg_and_raise_error("not in a function");
argv = argptr;
while ((name = *argv++) != NULL) {
mklocal(name);
}
return 0;
}
static int FAST_FUNC
falsecmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
return 1;
}
static int FAST_FUNC
truecmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
return 0;
}
static int FAST_FUNC
execcmd(int argc UNUSED_PARAM, char **argv)
{
if (argv[1]) {
iflag = 0; /* exit on error */
mflag = 0;
optschanged();
/* We should set up signals for "exec CMD"
* the same way as for "CMD" without "exec".
* But optschanged->setinteractive->setsignal
* still thought we are a root shell. Therefore, for example,
* SIGQUIT is still set to IGN. Fix it:
*/
shlvl++;
setsignal(SIGQUIT);
/*setsignal(SIGTERM); - unnecessary because of iflag=0 */
/*setsignal(SIGTSTP); - unnecessary because of mflag=0 */
/*setsignal(SIGTTOU); - unnecessary because of mflag=0 */
shellexec(argv + 1, pathval(), 0);
/* NOTREACHED */
}
return 0;
}
/*
* The return command.
*/
static int FAST_FUNC
returncmd(int argc UNUSED_PARAM, char **argv)
{
/*
* If called outside a function, do what ksh does;
* skip the rest of the file.
*/
evalskip = SKIPFUNC;
return argv[1] ? number(argv[1]) : exitstatus;
}
/* Forward declarations for builtintab[] */
static int breakcmd(int, char **) FAST_FUNC;
static int dotcmd(int, char **) FAST_FUNC;
static int evalcmd(int, char **, int) FAST_FUNC;
static int exitcmd(int, char **) FAST_FUNC;
static int exportcmd(int, char **) FAST_FUNC;
#if ENABLE_ASH_GETOPTS
static int getoptscmd(int, char **) FAST_FUNC;
#endif
#if ENABLE_ASH_HELP
static int helpcmd(int, char **) FAST_FUNC;
#endif
#if MAX_HISTORY
static int historycmd(int, char **) FAST_FUNC;
#endif
#if ENABLE_FEATURE_SH_MATH
static int letcmd(int, char **) FAST_FUNC;
#endif
static int readcmd(int, char **) FAST_FUNC;
static int setcmd(int, char **) FAST_FUNC;
static int shiftcmd(int, char **) FAST_FUNC;
static int timescmd(int, char **) FAST_FUNC;
static int trapcmd(int, char **) FAST_FUNC;
static int umaskcmd(int, char **) FAST_FUNC;
static int unsetcmd(int, char **) FAST_FUNC;
static int ulimitcmd(int, char **) FAST_FUNC;
#define BUILTIN_NOSPEC "0"
#define BUILTIN_SPECIAL "1"
#define BUILTIN_REGULAR "2"
#define BUILTIN_SPEC_REG "3"
#define BUILTIN_ASSIGN "4"
#define BUILTIN_SPEC_ASSG "5"
#define BUILTIN_REG_ASSG "6"
#define BUILTIN_SPEC_REG_ASSG "7"
/* Stubs for calling non-FAST_FUNC's */
#if ENABLE_ASH_BUILTIN_ECHO
static int FAST_FUNC echocmd(int argc, char **argv) { return echo_main(argc, argv); }
#endif
#if ENABLE_ASH_BUILTIN_PRINTF
static int FAST_FUNC printfcmd(int argc, char **argv) { return printf_main(argc, argv); }
#endif
#if ENABLE_ASH_BUILTIN_TEST
static int FAST_FUNC testcmd(int argc, char **argv) { return test_main(argc, argv); }
#endif
/* Keep these in proper order since it is searched via bsearch() */
static const struct builtincmd builtintab[] = {
{ BUILTIN_SPEC_REG "." , dotcmd },
{ BUILTIN_SPEC_REG ":" , truecmd },
#if ENABLE_ASH_BUILTIN_TEST
{ BUILTIN_REGULAR "[" , testcmd },
# if ENABLE_ASH_BASH_COMPAT
{ BUILTIN_REGULAR "[[" , testcmd },
# endif
#endif
#if ENABLE_ASH_ALIAS
{ BUILTIN_REG_ASSG "alias" , aliascmd },
#endif
#if JOBS
{ BUILTIN_REGULAR "bg" , fg_bgcmd },
#endif
{ BUILTIN_SPEC_REG "break" , breakcmd },
{ BUILTIN_REGULAR "cd" , cdcmd },
{ BUILTIN_NOSPEC "chdir" , cdcmd },
#if ENABLE_ASH_CMDCMD
{ BUILTIN_REGULAR "command" , commandcmd },
#endif
{ BUILTIN_SPEC_REG "continue", breakcmd },
#if ENABLE_ASH_BUILTIN_ECHO
{ BUILTIN_REGULAR "echo" , echocmd },
#endif
{ BUILTIN_SPEC_REG "eval" , NULL }, /*evalcmd() has a differing prototype*/
{ BUILTIN_SPEC_REG "exec" , execcmd },
{ BUILTIN_SPEC_REG "exit" , exitcmd },
{ BUILTIN_SPEC_REG_ASSG "export" , exportcmd },
{ BUILTIN_REGULAR "false" , falsecmd },
#if JOBS
{ BUILTIN_REGULAR "fg" , fg_bgcmd },
#endif
#if ENABLE_ASH_GETOPTS
{ BUILTIN_REGULAR "getopts" , getoptscmd },
#endif
{ BUILTIN_NOSPEC "hash" , hashcmd },
#if ENABLE_ASH_HELP
{ BUILTIN_NOSPEC "help" , helpcmd },
#endif
#if MAX_HISTORY
{ BUILTIN_NOSPEC "history" , historycmd },
#endif
#if JOBS
{ BUILTIN_REGULAR "jobs" , jobscmd },
{ BUILTIN_REGULAR "kill" , killcmd },
#endif
#if ENABLE_FEATURE_SH_MATH
{ BUILTIN_NOSPEC "let" , letcmd },
#endif
{ BUILTIN_ASSIGN "local" , localcmd },
#if ENABLE_ASH_BUILTIN_PRINTF
{ BUILTIN_REGULAR "printf" , printfcmd },
#endif
{ BUILTIN_NOSPEC "pwd" , pwdcmd },
{ BUILTIN_REGULAR "read" , readcmd },
{ BUILTIN_SPEC_REG_ASSG "readonly", exportcmd },
{ BUILTIN_SPEC_REG "return" , returncmd },
{ BUILTIN_SPEC_REG "set" , setcmd },
{ BUILTIN_SPEC_REG "shift" , shiftcmd },
#if ENABLE_ASH_BASH_COMPAT
{ BUILTIN_SPEC_REG "source" , dotcmd },
#endif
#if ENABLE_ASH_BUILTIN_TEST
{ BUILTIN_REGULAR "test" , testcmd },
#endif
{ BUILTIN_SPEC_REG "times" , timescmd },
{ BUILTIN_SPEC_REG "trap" , trapcmd },
{ BUILTIN_REGULAR "true" , truecmd },
{ BUILTIN_NOSPEC "type" , typecmd },
{ BUILTIN_NOSPEC "ulimit" , ulimitcmd },
{ BUILTIN_REGULAR "umask" , umaskcmd },
#if ENABLE_ASH_ALIAS
{ BUILTIN_REGULAR "unalias" , unaliascmd },
#endif
{ BUILTIN_SPEC_REG "unset" , unsetcmd },
{ BUILTIN_REGULAR "wait" , waitcmd },
};
/* Should match the above table! */
#define COMMANDCMD (builtintab + \
/* . : */ 2 + \
/* [ */ 1 * ENABLE_ASH_BUILTIN_TEST + \
/* [[ */ 1 * ENABLE_ASH_BUILTIN_TEST * ENABLE_ASH_BASH_COMPAT + \
/* alias */ 1 * ENABLE_ASH_ALIAS + \
/* bg */ 1 * ENABLE_ASH_JOB_CONTROL + \
/* break cd cddir */ 3)
#define EVALCMD (COMMANDCMD + \
/* command */ 1 * ENABLE_ASH_CMDCMD + \
/* continue */ 1 + \
/* echo */ 1 * ENABLE_ASH_BUILTIN_ECHO + \
0)
#define EXECCMD (EVALCMD + \
/* eval */ 1)
/*
* Search the table of builtin commands.
*/
static int
pstrcmp1(const void *a, const void *b)
{
return strcmp((char*)a, *(char**)b + 1);
}
static struct builtincmd *
find_builtin(const char *name)
{
struct builtincmd *bp;
bp = bsearch(
name, builtintab, ARRAY_SIZE(builtintab), sizeof(builtintab[0]),
pstrcmp1
);
return bp;
}
/*
* Execute a simple command.
*/
static int
isassignment(const char *p)
{
const char *q = endofname(p);
if (p == q)
return 0;
return *q == '=';
}
static int FAST_FUNC
bltincmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
/* Preserve exitstatus of a previous possible redirection
* as POSIX mandates */
return back_exitstatus;
}
static int
evalcommand(union node *cmd, int flags)
{
static const struct builtincmd null_bltin = {
"\0\0", bltincmd /* why three NULs? */
};
struct stackmark smark;
union node *argp;
struct arglist arglist;
struct arglist varlist;
char **argv;
int argc;
const struct strlist *sp;
struct cmdentry cmdentry;
struct job *jp;
char *lastarg;
const char *path;
int spclbltin;
int status;
char **nargv;
struct builtincmd *bcmd;
smallint cmd_is_exec;
smallint pseudovarflag = 0;
/* First expand the arguments. */
TRACE(("evalcommand(0x%lx, %d) called\n", (long)cmd, flags));
setstackmark(&smark);
back_exitstatus = 0;
cmdentry.cmdtype = CMDBUILTIN;
cmdentry.u.cmd = &null_bltin;
varlist.lastp = &varlist.list;
*varlist.lastp = NULL;
arglist.lastp = &arglist.list;
*arglist.lastp = NULL;
argc = 0;
if (cmd->ncmd.args) {
bcmd = find_builtin(cmd->ncmd.args->narg.text);
pseudovarflag = bcmd && IS_BUILTIN_ASSIGN(bcmd);
}
for (argp = cmd->ncmd.args; argp; argp = argp->narg.next) {
struct strlist **spp;
spp = arglist.lastp;
if (pseudovarflag && isassignment(argp->narg.text))
expandarg(argp, &arglist, EXP_VARTILDE);
else
expandarg(argp, &arglist, EXP_FULL | EXP_TILDE);
for (sp = *spp; sp; sp = sp->next)
argc++;
}
/* Reserve one extra spot at the front for shellexec. */
nargv = stalloc(sizeof(char *) * (argc + 2));
argv = ++nargv;
for (sp = arglist.list; sp; sp = sp->next) {
TRACE(("evalcommand arg: %s\n", sp->text));
*nargv++ = sp->text;
}
*nargv = NULL;
lastarg = NULL;
if (iflag && funcnest == 0 && argc > 0)
lastarg = nargv[-1];
preverrout_fd = 2;
expredir(cmd->ncmd.redirect);
status = redirectsafe(cmd->ncmd.redirect, REDIR_PUSH | REDIR_SAVEFD2);
path = vpath.var_text;
for (argp = cmd->ncmd.assign; argp; argp = argp->narg.next) {
struct strlist **spp;
char *p;
spp = varlist.lastp;
expandarg(argp, &varlist, EXP_VARTILDE);
/*
* Modify the command lookup path, if a PATH= assignment
* is present
*/
p = (*spp)->text;
if (varcmp(p, path) == 0)
path = p;
}
/* Print the command if xflag is set. */
if (xflag) {
int n;
const char *p = " %s" + 1;
fdprintf(preverrout_fd, p, expandstr(ps4val()));
sp = varlist.list;
for (n = 0; n < 2; n++) {
while (sp) {
fdprintf(preverrout_fd, p, sp->text);
sp = sp->next;
p = " %s";
}
sp = arglist.list;
}
safe_write(preverrout_fd, "\n", 1);
}
cmd_is_exec = 0;
spclbltin = -1;
/* Now locate the command. */
if (argc) {
int cmd_flag = DO_ERR;
#if ENABLE_ASH_CMDCMD
const char *oldpath = path + 5;
#endif
path += 5;
for (;;) {
find_command(argv[0], &cmdentry, cmd_flag, path);
if (cmdentry.cmdtype == CMDUNKNOWN) {
flush_stdout_stderr();
status = 127;
goto bail;
}
/* implement bltin and command here */
if (cmdentry.cmdtype != CMDBUILTIN)
break;
if (spclbltin < 0)
spclbltin = IS_BUILTIN_SPECIAL(cmdentry.u.cmd);
if (cmdentry.u.cmd == EXECCMD)
cmd_is_exec = 1;
#if ENABLE_ASH_CMDCMD
if (cmdentry.u.cmd == COMMANDCMD) {
path = oldpath;
nargv = parse_command_args(argv, &path);
if (!nargv)
break;
/* It's "command [-p] PROG ARGS" (that is, no -Vv).
* nargv => "PROG". path is updated if -p.
*/
argc -= nargv - argv;
argv = nargv;
cmd_flag |= DO_NOFUNC;
} else
#endif
break;
}
}
if (status) {
/* We have a redirection error. */
if (spclbltin > 0)
raise_exception(EXERROR);
bail:
exitstatus = status;
goto out;
}
/* Execute the command. */
switch (cmdentry.cmdtype) {
default: {
#if ENABLE_FEATURE_SH_NOFORK
/* (1) BUG: if variables are set, we need to fork, or save/restore them
* around run_nofork_applet() call.
* (2) Should this check also be done in forkshell()?
* (perhaps it should, so that "VAR=VAL nofork" at least avoids exec...)
*/
/* find_command() encodes applet_no as (-2 - applet_no) */
int applet_no = (- cmdentry.u.index - 2);
if (applet_no >= 0 && APPLET_IS_NOFORK(applet_no)) {
listsetvar(varlist.list, VEXPORT|VSTACK);
/* run <applet>_main() */
status = run_nofork_applet(applet_no, argv);
break;
}
#endif
/* Can we avoid forking off? For example, very last command
* in a script or a subshell does not need forking,
* we can just exec it.
*/
if (!(flags & EV_EXIT) || may_have_traps) {
/* No, forking off a child is necessary */
INT_OFF;
jp = makejob(/*cmd,*/ 1);
if (forkshell(jp, cmd, FORK_FG) != 0) {
/* parent */
status = waitforjob(jp);
INT_ON;
TRACE(("forked child exited with %d\n", status));
break;
}
/* child */
FORCE_INT_ON;
/* fall through to exec'ing external program */
}
listsetvar(varlist.list, VEXPORT|VSTACK);
shellexec(argv, path, cmdentry.u.index);
/* NOTREACHED */
} /* default */
case CMDBUILTIN:
cmdenviron = varlist.list;
if (cmdenviron) {
struct strlist *list = cmdenviron;
int i = VNOSET;
if (spclbltin > 0 || argc == 0) {
i = 0;
if (cmd_is_exec && argc > 1)
i = VEXPORT;
}
listsetvar(list, i);
}
/* Tight loop with builtins only:
* "while kill -0 $child; do true; done"
* will never exit even if $child died, unless we do this
* to reap the zombie and make kill detect that it's gone: */
dowait(DOWAIT_NONBLOCK, NULL);
if (evalbltin(cmdentry.u.cmd, argc, argv, flags)) {
if (exception_type == EXERROR && spclbltin <= 0) {
FORCE_INT_ON;
goto readstatus;
}
raise:
longjmp(exception_handler->loc, 1);
}
goto readstatus;
case CMDFUNCTION:
listsetvar(varlist.list, 0);
/* See above for the rationale */
dowait(DOWAIT_NONBLOCK, NULL);
if (evalfun(cmdentry.u.func, argc, argv, flags))
goto raise;
readstatus:
status = exitstatus;
break;
} /* switch */
out:
if (cmd->ncmd.redirect)
popredir(/*drop:*/ cmd_is_exec, /*restore:*/ cmd_is_exec);
if (lastarg) {
/* dsl: I think this is intended to be used to support
* '_' in 'vi' command mode during line editing...
* However I implemented that within libedit itself.
*/
setvar0("_", lastarg);
}
popstackmark(&smark);
return status;
}
static int
evalbltin(const struct builtincmd *cmd, int argc, char **argv, int flags)
{
char *volatile savecmdname;
struct jmploc *volatile savehandler;
struct jmploc jmploc;
int status;
int i;
savecmdname = commandname;
savehandler = exception_handler;
i = setjmp(jmploc.loc);
if (i)
goto cmddone;
exception_handler = &jmploc;
commandname = argv[0];
argptr = argv + 1;
optptr = NULL; /* initialize nextopt */
if (cmd == EVALCMD)
status = evalcmd(argc, argv, flags);
else
status = (*cmd->builtin)(argc, argv);
flush_stdout_stderr();
status |= ferror(stdout);
exitstatus = status;
cmddone:
clearerr(stdout);
commandname = savecmdname;
exception_handler = savehandler;
return i;
}
static int
goodname(const char *p)
{
return endofname(p)[0] == '\0';
}
/*
* Search for a command. This is called before we fork so that the
* location of the command will be available in the parent as well as
* the child. The check for "goodname" is an overly conservative
* check that the name will not be subject to expansion.
*/
static void
prehash(union node *n)
{
struct cmdentry entry;
if (n->type == NCMD && n->ncmd.args && goodname(n->ncmd.args->narg.text))
find_command(n->ncmd.args->narg.text, &entry, 0, pathval());
}
/* ============ Builtin commands
*
* Builtin commands whose functions are closely tied to evaluation
* are implemented here.
*/
/*
* Handle break and continue commands. Break, continue, and return are
* all handled by setting the evalskip flag. The evaluation routines
* above all check this flag, and if it is set they start skipping
* commands rather than executing them. The variable skipcount is
* the number of loops to break/continue, or the number of function
* levels to return. (The latter is always 1.) It should probably
* be an error to break out of more loops than exist, but it isn't
* in the standard shell so we don't make it one here.
*/
static int FAST_FUNC
breakcmd(int argc UNUSED_PARAM, char **argv)
{
int n = argv[1] ? number(argv[1]) : 1;
if (n <= 0)
ash_msg_and_raise_error(msg_illnum, argv[1]);
if (n > loopnest)
n = loopnest;
if (n > 0) {
evalskip = (**argv == 'c') ? SKIPCONT : SKIPBREAK;
skipcount = n;
}
return 0;
}
/*
* This implements the input routines used by the parser.
*/
enum {
INPUT_PUSH_FILE = 1,
INPUT_NOFILE_OK = 2,
};
static smallint checkkwd;
/* values of checkkwd variable */
#define CHKALIAS 0x1
#define CHKKWD 0x2
#define CHKNL 0x4
/*
* Push a string back onto the input at this current parsefile level.
* We handle aliases this way.
*/
#if !ENABLE_ASH_ALIAS
#define pushstring(s, ap) pushstring(s)
#endif
static void
pushstring(char *s, struct alias *ap)
{
struct strpush *sp;
int len;
len = strlen(s);
INT_OFF;
if (g_parsefile->strpush) {
sp = ckzalloc(sizeof(*sp));
sp->prev = g_parsefile->strpush;
} else {
sp = &(g_parsefile->basestrpush);
}
g_parsefile->strpush = sp;
sp->prev_string = g_parsefile->next_to_pgetc;
sp->prev_left_in_line = g_parsefile->left_in_line;
sp->unget = g_parsefile->unget;
memcpy(sp->lastc, g_parsefile->lastc, sizeof(sp->lastc));
#if ENABLE_ASH_ALIAS
sp->ap = ap;
if (ap) {
ap->flag |= ALIASINUSE;
sp->string = s;
}
#endif
g_parsefile->next_to_pgetc = s;
g_parsefile->left_in_line = len;
g_parsefile->unget = 0;
INT_ON;
}
static void
popstring(void)
{
struct strpush *sp = g_parsefile->strpush;
INT_OFF;
#if ENABLE_ASH_ALIAS
if (sp->ap) {
if (g_parsefile->next_to_pgetc[-1] == ' '
|| g_parsefile->next_to_pgetc[-1] == '\t'
) {
checkkwd |= CHKALIAS;
}
if (sp->string != sp->ap->val) {
free(sp->string);
}
sp->ap->flag &= ~ALIASINUSE;
if (sp->ap->flag & ALIASDEAD) {
unalias(sp->ap->name);
}
}
#endif
g_parsefile->next_to_pgetc = sp->prev_string;
g_parsefile->left_in_line = sp->prev_left_in_line;
g_parsefile->unget = sp->unget;
memcpy(g_parsefile->lastc, sp->lastc, sizeof(sp->lastc));
g_parsefile->strpush = sp->prev;
if (sp != &(g_parsefile->basestrpush))
free(sp);
INT_ON;
}
static int
preadfd(void)
{
int nr;
char *buf = g_parsefile->buf;
g_parsefile->next_to_pgetc = buf;
#if ENABLE_FEATURE_EDITING
retry:
if (!iflag || g_parsefile->pf_fd != STDIN_FILENO)
nr = nonblock_immune_read(g_parsefile->pf_fd, buf, IBUFSIZ - 1);
else {
int timeout = -1;
# if ENABLE_ASH_IDLE_TIMEOUT
if (iflag) {
const char *tmout_var = lookupvar("TMOUT");
if (tmout_var) {
timeout = atoi(tmout_var) * 1000;
if (timeout <= 0)
timeout = -1;
}
}
# endif
# if ENABLE_FEATURE_TAB_COMPLETION
line_input_state->path_lookup = pathval();
# endif
reinit_unicode_for_ash();
nr = read_line_input(line_input_state, cmdedit_prompt, buf, IBUFSIZ, timeout);
if (nr == 0) {
/* ^C pressed, "convert" to SIGINT */
write(STDOUT_FILENO, "^C", 2);
if (trap[SIGINT]) {
buf[0] = '\n';
buf[1] = '\0';
raise(SIGINT);
return 1;
}
exitstatus = 128 + SIGINT;
bb_putchar('\n');
goto retry;
}
if (nr < 0) {
if (errno == 0) {
/* Ctrl+D pressed */
nr = 0;
}
# if ENABLE_ASH_IDLE_TIMEOUT
else if (errno == EAGAIN && timeout > 0) {
puts("\007timed out waiting for input: auto-logout");
exitshell();
}
# endif
}
}
#else
nr = nonblock_immune_read(g_parsefile->pf_fd, buf, IBUFSIZ - 1);
#endif
#if 0 /* disabled: nonblock_immune_read() handles this problem */
if (nr < 0) {
if (parsefile->fd == 0 && errno == EWOULDBLOCK) {
int flags = fcntl(0, F_GETFL);
if (flags >= 0 && (flags & O_NONBLOCK)) {
flags &= ~O_NONBLOCK;
if (fcntl(0, F_SETFL, flags) >= 0) {
out2str("sh: turning off NDELAY mode\n");
goto retry;
}
}
}
}
#endif
return nr;
}
/*
* Refill the input buffer and return the next input character:
*
* 1) If a string was pushed back on the input, pop it;
* 2) If an EOF was pushed back (g_parsefile->left_in_line < -BIGNUM)
* or we are reading from a string so we can't refill the buffer,
* return EOF.
* 3) If there is more stuff in this buffer, use it else call read to fill it.
* 4) Process input up to the next newline, deleting nul characters.
*/
//#define pgetc_debug(...) bb_error_msg(__VA_ARGS__)
#define pgetc_debug(...) ((void)0)
static int pgetc(void);
static int
preadbuffer(void)
{
char *q;
int more;
if (g_parsefile->strpush) {
#if ENABLE_ASH_ALIAS
if (g_parsefile->left_in_line == -1
&& g_parsefile->strpush->ap
&& g_parsefile->next_to_pgetc[-1] != ' '
&& g_parsefile->next_to_pgetc[-1] != '\t'
) {
pgetc_debug("preadbuffer PEOA");
return PEOA;
}
#endif
popstring();
return pgetc();
}
/* on both branches above g_parsefile->left_in_line < 0.
* "pgetc" needs refilling.
*/
/* -90 is our -BIGNUM. Below we use -99 to mark "EOF on read",
* pungetc() may increment it a few times.
* Assuming it won't increment it to less than -90.
*/
if (g_parsefile->left_in_line < -90 || g_parsefile->buf == NULL) {
pgetc_debug("preadbuffer PEOF1");
/* even in failure keep left_in_line and next_to_pgetc
* in lock step, for correct multi-layer pungetc.
* left_in_line was decremented before preadbuffer(),
* must inc next_to_pgetc: */
g_parsefile->next_to_pgetc++;
return PEOF;
}
more = g_parsefile->left_in_buffer;
if (more <= 0) {
flush_stdout_stderr();
again:
more = preadfd();
if (more <= 0) {
/* don't try reading again */
g_parsefile->left_in_line = -99;
pgetc_debug("preadbuffer PEOF2");
g_parsefile->next_to_pgetc++;
return PEOF;
}
}
/* Find out where's the end of line.
* Set g_parsefile->left_in_line
* and g_parsefile->left_in_buffer acordingly.
* NUL chars are deleted.
*/
q = g_parsefile->next_to_pgetc;
for (;;) {
char c;
more--;
c = *q;
if (c == '\0') {
memmove(q, q + 1, more);
} else {
q++;
if (c == '\n') {
g_parsefile->left_in_line = q - g_parsefile->next_to_pgetc - 1;
break;
}
}
if (more <= 0) {
g_parsefile->left_in_line = q - g_parsefile->next_to_pgetc - 1;
if (g_parsefile->left_in_line < 0)
goto again;
break;
}
}
g_parsefile->left_in_buffer = more;
if (vflag) {
char save = *q;
*q = '\0';
out2str(g_parsefile->next_to_pgetc);
*q = save;
}
pgetc_debug("preadbuffer at %d:%p'%s'",
g_parsefile->left_in_line,
g_parsefile->next_to_pgetc,
g_parsefile->next_to_pgetc);
return (unsigned char)*g_parsefile->next_to_pgetc++;
}
static void
nlprompt(void)
{
g_parsefile->linno++;
setprompt_if(doprompt, 2);
}
static void
nlnoprompt(void)
{
g_parsefile->linno++;
needprompt = doprompt;
}
static int
pgetc(void)
{
int c;
pgetc_debug("pgetc at %d:%p'%s'",
g_parsefile->left_in_line,
g_parsefile->next_to_pgetc,
g_parsefile->next_to_pgetc);
if (g_parsefile->unget)
return g_parsefile->lastc[--g_parsefile->unget];
if (--g_parsefile->left_in_line >= 0)
c = (unsigned char)*g_parsefile->next_to_pgetc++;
else
c = preadbuffer();
g_parsefile->lastc[1] = g_parsefile->lastc[0];
g_parsefile->lastc[0] = c;
return c;
}
#if ENABLE_ASH_ALIAS
static int
pgetc_without_PEOA(void)
{
int c;
do {
pgetc_debug("pgetc at %d:%p'%s'",
g_parsefile->left_in_line,
g_parsefile->next_to_pgetc,
g_parsefile->next_to_pgetc);
c = pgetc();
} while (c == PEOA);
return c;
}
#else
# define pgetc_without_PEOA() pgetc()
#endif
/*
* Read a line from the script.
*/
static char *
pfgets(char *line, int len)
{
char *p = line;
int nleft = len;
int c;
while (--nleft > 0) {
c = pgetc_without_PEOA();
if (c == PEOF) {
if (p == line)
return NULL;
break;
}
*p++ = c;
if (c == '\n')
break;
}
*p = '\0';
return line;
}
/*
* Undo a call to pgetc. Only two characters may be pushed back.
* PEOF may be pushed back.
*/
static void
pungetc(void)
{
g_parsefile->unget++;
}
/* This one eats backslash+newline */
static int
pgetc_eatbnl(void)
{
int c;
while ((c = pgetc()) == '\\') {
if (pgetc() != '\n') {
pungetc();
break;
}
nlprompt();
}
return c;
}
/*
* To handle the "." command, a stack of input files is used. Pushfile
* adds a new entry to the stack and popfile restores the previous level.
*/
static void
pushfile(void)
{
struct parsefile *pf;
pf = ckzalloc(sizeof(*pf));
pf->prev = g_parsefile;
pf->pf_fd = -1;
/*pf->strpush = NULL; - ckzalloc did it */
/*pf->basestrpush.prev = NULL;*/
/*pf->unget = 0;*/
g_parsefile = pf;
}
static void
popfile(void)
{
struct parsefile *pf = g_parsefile;
if (pf == &basepf)
return;
INT_OFF;
if (pf->pf_fd >= 0)
close(pf->pf_fd);
free(pf->buf);
while (pf->strpush)
popstring();
g_parsefile = pf->prev;
free(pf);
INT_ON;
}
/*
* Return to top level.
*/
static void
popallfiles(void)
{
while (g_parsefile != &basepf)
popfile();
}
/*
* Close the file(s) that the shell is reading commands from. Called
* after a fork is done.
*/
static void
closescript(void)
{
popallfiles();
if (g_parsefile->pf_fd > 0) {
close(g_parsefile->pf_fd);
g_parsefile->pf_fd = 0;
}
}
/*
* Like setinputfile, but takes an open file descriptor. Call this with
* interrupts off.
*/
static void
setinputfd(int fd, int push)
{
if (push) {
pushfile();
g_parsefile->buf = NULL;
}
g_parsefile->pf_fd = fd;
if (g_parsefile->buf == NULL)
g_parsefile->buf = ckmalloc(IBUFSIZ);
g_parsefile->left_in_buffer = 0;
g_parsefile->left_in_line = 0;
g_parsefile->linno = 1;
}
/*
* Set the input to take input from a file. If push is set, push the
* old input onto the stack first.
*/
static int
setinputfile(const char *fname, int flags)
{
int fd;
INT_OFF;
fd = open(fname, O_RDONLY);
if (fd < 0) {
if (flags & INPUT_NOFILE_OK)
goto out;
exitstatus = 127;
ash_msg_and_raise_error("can't open '%s'", fname);
}
if (fd < 10)
fd = savefd(fd);
else
close_on_exec_on(fd);
setinputfd(fd, flags & INPUT_PUSH_FILE);
out:
INT_ON;
return fd;
}
/*
* Like setinputfile, but takes input from a string.
*/
static void
setinputstring(char *string)
{
INT_OFF;
pushfile();
g_parsefile->next_to_pgetc = string;
g_parsefile->left_in_line = strlen(string);
g_parsefile->buf = NULL;
g_parsefile->linno = 1;
INT_ON;
}
/*
* Routines to check for mail.
*/
#if ENABLE_ASH_MAIL
/* Hash of mtimes of mailboxes */
static unsigned mailtime_hash;
/* Set if MAIL or MAILPATH is changed. */
static smallint mail_var_path_changed;
/*
* Print appropriate message(s) if mail has arrived.
* If mail_var_path_changed is set,
* then the value of MAIL has mail_var_path_changed,
* so we just update the values.
*/
static void
chkmail(void)
{
const char *mpath;
char *p;
char *q;
unsigned new_hash;
struct stackmark smark;
struct stat statb;
setstackmark(&smark);
mpath = mpathset() ? mpathval() : mailval();
new_hash = 0;
for (;;) {
p = path_advance(&mpath, nullstr);
if (p == NULL)
break;
if (*p == '\0')
continue;
for (q = p; *q; q++)
continue;
#if DEBUG
if (q[-1] != '/')
abort();
#endif
q[-1] = '\0'; /* delete trailing '/' */
if (stat(p, &statb) < 0) {
continue;
}
/* Very simplistic "hash": just a sum of all mtimes */
new_hash += (unsigned)statb.st_mtime;
}
if (!mail_var_path_changed && mailtime_hash != new_hash) {
if (mailtime_hash != 0)
out2str("you have mail\n");
mailtime_hash = new_hash;
}
mail_var_path_changed = 0;
popstackmark(&smark);
}
static void FAST_FUNC
changemail(const char *val UNUSED_PARAM)
{
mail_var_path_changed = 1;
}
#endif /* ASH_MAIL */
/* ============ ??? */
/*
* Set the shell parameters.
*/
static void
setparam(char **argv)
{
char **newparam;
char **ap;
int nparam;
for (nparam = 0; argv[nparam]; nparam++)
continue;
ap = newparam = ckmalloc((nparam + 1) * sizeof(*ap));
while (*argv) {
*ap++ = ckstrdup(*argv++);
}
*ap = NULL;
freeparam(&shellparam);
shellparam.malloced = 1;
shellparam.nparam = nparam;
shellparam.p = newparam;
#if ENABLE_ASH_GETOPTS
shellparam.optind = 1;
shellparam.optoff = -1;
#endif
}
/*
* Process shell options. The global variable argptr contains a pointer
* to the argument list; we advance it past the options.
*
* SUSv3 section 2.8.1 "Consequences of Shell Errors" says:
* For a non-interactive shell, an error condition encountered
* by a special built-in ... shall cause the shell to write a diagnostic message
* to standard error and exit as shown in the following table:
* Error Special Built-In
* ...
* Utility syntax error (option or operand error) Shall exit
* ...
* However, in bug 1142 (http://busybox.net/bugs/view.php?id=1142)
* we see that bash does not do that (set "finishes" with error code 1 instead,
* and shell continues), and people rely on this behavior!
* Testcase:
* set -o barfoo 2>/dev/null
* echo $?
*
* Oh well. Let's mimic that.
*/
static int
plus_minus_o(char *name, int val)
{
int i;
if (name) {
for (i = 0; i < NOPTS; i++) {
if (strcmp(name, optnames(i)) == 0) {
optlist[i] = val;
return 0;
}
}
ash_msg("illegal option %co %s", val ? '-' : '+', name);
return 1;
}
for (i = 0; i < NOPTS; i++) {
if (val) {
out1fmt("%-16s%s\n", optnames(i), optlist[i] ? "on" : "off");
} else {
out1fmt("set %co %s\n", optlist[i] ? '-' : '+', optnames(i));
}
}
return 0;
}
static void
setoption(int flag, int val)
{
int i;
for (i = 0; i < NOPTS; i++) {
if (optletters(i) == flag) {
optlist[i] = val;
return;
}
}
ash_msg_and_raise_error("illegal option %c%c", val ? '-' : '+', flag);
/* NOTREACHED */
}
static int
options(int cmdline)
{
char *p;
int val;
int c;
if (cmdline)
minusc = NULL;
while ((p = *argptr) != NULL) {
c = *p++;
if (c != '-' && c != '+')
break;
argptr++;
val = 0; /* val = 0 if c == '+' */
if (c == '-') {
val = 1;
if (p[0] == '\0' || LONE_DASH(p)) {
if (!cmdline) {
/* "-" means turn off -x and -v */
if (p[0] == '\0')
xflag = vflag = 0;
/* "--" means reset params */
else if (*argptr == NULL)
setparam(argptr);
}
break; /* "-" or "--" terminates options */
}
}
/* first char was + or - */
while ((c = *p++) != '\0') {
/* bash 3.2 indeed handles -c CMD and +c CMD the same */
if (c == 'c' && cmdline) {
minusc = p; /* command is after shell args */
} else if (c == 'o') {
if (plus_minus_o(*argptr, val)) {
/* it already printed err message */
return 1; /* error */
}
if (*argptr)
argptr++;
} else if (cmdline && (c == 'l')) { /* -l or +l == --login */
isloginsh = 1;
/* bash does not accept +-login, we also won't */
} else if (cmdline && val && (c == '-')) { /* long options */
if (strcmp(p, "login") == 0)
isloginsh = 1;
break;
} else {
setoption(c, val);
}
}
}
return 0;
}
/*
* The shift builtin command.
*/
static int FAST_FUNC
shiftcmd(int argc UNUSED_PARAM, char **argv)
{
int n;
char **ap1, **ap2;
n = 1;
if (argv[1])
n = number(argv[1]);
if (n > shellparam.nparam)
n = 0; /* bash compat, was = shellparam.nparam; */
INT_OFF;
shellparam.nparam -= n;
for (ap1 = shellparam.p; --n >= 0; ap1++) {
if (shellparam.malloced)
free(*ap1);
}
ap2 = shellparam.p;
while ((*ap2++ = *ap1++) != NULL)
continue;
#if ENABLE_ASH_GETOPTS
shellparam.optind = 1;
shellparam.optoff = -1;
#endif
INT_ON;
return 0;
}
/*
* POSIX requires that 'set' (but not export or readonly) output the
* variables in lexicographic order - by the locale's collating order (sigh).
* Maybe we could keep them in an ordered balanced binary tree
* instead of hashed lists.
* For now just roll 'em through qsort for printing...
*/
static int
showvars(const char *sep_prefix, int on, int off)
{
const char *sep;
char **ep, **epend;
ep = listvars(on, off, &epend);
qsort(ep, epend - ep, sizeof(char *), vpcmp);
sep = *sep_prefix ? " " : sep_prefix;
for (; ep < epend; ep++) {
const char *p;
const char *q;
p = strchrnul(*ep, '=');
q = nullstr;
if (*p)
q = single_quote(++p);
out1fmt("%s%s%.*s%s\n", sep_prefix, sep, (int)(p - *ep), *ep, q);
}
return 0;
}
/*
* The set command builtin.
*/
static int FAST_FUNC
setcmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
int retval;
if (!argv[1])
return showvars(nullstr, 0, VUNSET);
INT_OFF;
retval = options(/*cmdline:*/ 0);
if (retval == 0) { /* if no parse error... */
optschanged();
if (*argptr != NULL) {
setparam(argptr);
}
}
INT_ON;
return retval;
}
#if ENABLE_ASH_RANDOM_SUPPORT
static void FAST_FUNC
change_random(const char *value)
{
uint32_t t;
if (value == NULL) {
/* "get", generate */
t = next_random(&random_gen);
/* set without recursion */
setvar(vrandom.var_text, utoa(t), VNOFUNC);
vrandom.flags &= ~VNOFUNC;
} else {
/* set/reset */
t = strtoul(value, NULL, 10);
INIT_RANDOM_T(&random_gen, (t ? t : 1), t);
}
}
#endif
#if ENABLE_ASH_GETOPTS
static int
getopts(char *optstr, char *optvar, char **optfirst)
{
char *p, *q;
char c = '?';
int done = 0;
char sbuf[2];
char **optnext;
int ind = shellparam.optind;
int off = shellparam.optoff;
sbuf[1] = '\0';
shellparam.optind = -1;
optnext = optfirst + ind - 1;
if (ind <= 1 || off < 0 || (int)strlen(optnext[-1]) < off)
p = NULL;
else
p = optnext[-1] + off;
if (p == NULL || *p == '\0') {
/* Current word is done, advance */
p = *optnext;
if (p == NULL || *p != '-' || *++p == '\0') {
atend:
p = NULL;
done = 1;
goto out;
}
optnext++;
if (LONE_DASH(p)) /* check for "--" */
goto atend;
}
c = *p++;
for (q = optstr; *q != c;) {
if (*q == '\0') {
if (optstr[0] == ':') {
sbuf[0] = c;
/*sbuf[1] = '\0'; - already is */
setvar0("OPTARG", sbuf);
} else {
fprintf(stderr, "Illegal option -%c\n", c);
unsetvar("OPTARG");
}
c = '?';
goto out;
}
if (*++q == ':')
q++;
}
if (*++q == ':') {
if (*p == '\0' && (p = *optnext) == NULL) {
if (optstr[0] == ':') {
sbuf[0] = c;
/*sbuf[1] = '\0'; - already is */
setvar0("OPTARG", sbuf);
c = ':';
} else {
fprintf(stderr, "No arg for -%c option\n", c);
unsetvar("OPTARG");
c = '?';
}
goto out;
}
if (p == *optnext)
optnext++;
setvar0("OPTARG", p);
p = NULL;
} else
setvar0("OPTARG", nullstr);
out:
ind = optnext - optfirst + 1;
setvar("OPTIND", itoa(ind), VNOFUNC);
sbuf[0] = c;
/*sbuf[1] = '\0'; - already is */
setvar0(optvar, sbuf);
shellparam.optoff = p ? p - *(optnext - 1) : -1;
shellparam.optind = ind;
return done;
}
/*
* The getopts builtin. Shellparam.optnext points to the next argument
* to be processed. Shellparam.optptr points to the next character to
* be processed in the current argument. If shellparam.optnext is NULL,
* then it's the first time getopts has been called.
*/
static int FAST_FUNC
getoptscmd(int argc, char **argv)
{
char **optbase;
if (argc < 3)
ash_msg_and_raise_error("usage: getopts optstring var [arg]");
if (argc == 3) {
optbase = shellparam.p;
if ((unsigned)shellparam.optind > shellparam.nparam + 1) {
shellparam.optind = 1;
shellparam.optoff = -1;
}
} else {
optbase = &argv[3];
if ((unsigned)shellparam.optind > argc - 2) {
shellparam.optind = 1;
shellparam.optoff = -1;
}
}
return getopts(argv[1], argv[2], optbase);
}
#endif /* ASH_GETOPTS */
/* ============ Shell parser */
struct heredoc {
struct heredoc *next; /* next here document in list */
union node *here; /* redirection node */
char *eofmark; /* string indicating end of input */
smallint striptabs; /* if set, strip leading tabs */
};
static smallint tokpushback; /* last token pushed back */
static smallint quoteflag; /* set if (part of) last token was quoted */
static token_id_t lasttoken; /* last token read (integer id Txxx) */
static struct heredoc *heredoclist; /* list of here documents to read */
static char *wordtext; /* text of last word returned by readtoken */
static struct nodelist *backquotelist;
static union node *redirnode;
static struct heredoc *heredoc;
static const char *
tokname(char *buf, int tok)
{
if (tok < TSEMI)
return tokname_array[tok];
sprintf(buf, "\"%s\"", tokname_array[tok]);
return buf;
}
/* raise_error_unexpected_syntax:
* Called when an unexpected token is read during the parse. The argument
* is the token that is expected, or -1 if more than one type of token can
* occur at this point.
*/
static void raise_error_unexpected_syntax(int) NORETURN;
static void
raise_error_unexpected_syntax(int token)
{
char msg[64];
char buf[16];
int l;
l = sprintf(msg, "unexpected %s", tokname(buf, lasttoken));
if (token >= 0)
sprintf(msg + l, " (expecting %s)", tokname(buf, token));
raise_error_syntax(msg);
/* NOTREACHED */
}
#define EOFMARKLEN 79
/* parsing is heavily cross-recursive, need these forward decls */
static union node *andor(void);
static union node *pipeline(void);
static union node *parse_command(void);
static void parseheredoc(void);
static int peektoken(void);
static int readtoken(void);
static union node *
list(int nlflag)
{
union node *n1, *n2, *n3;
int tok;
n1 = NULL;
for (;;) {
switch (peektoken()) {
case TNL:
if (!(nlflag & 1))
break;
parseheredoc();
return n1;
case TEOF:
if (!n1 && (nlflag & 1))
n1 = NODE_EOF;
parseheredoc();
return n1;
}
checkkwd = CHKNL | CHKKWD | CHKALIAS;
if (nlflag == 2 && ((1 << peektoken()) & tokendlist))
return n1;
nlflag |= 2;
n2 = andor();
tok = readtoken();
if (tok == TBACKGND) {
if (n2->type == NPIPE) {
n2->npipe.pipe_backgnd = 1;
} else {
if (n2->type != NREDIR) {
n3 = stzalloc(sizeof(struct nredir));
n3->nredir.n = n2;
/*n3->nredir.redirect = NULL; - stzalloc did it */
n2 = n3;
}
n2->type = NBACKGND;
}
}
if (n1 == NULL) {
n1 = n2;
} else {
n3 = stzalloc(sizeof(struct nbinary));
n3->type = NSEMI;
n3->nbinary.ch1 = n1;
n3->nbinary.ch2 = n2;
n1 = n3;
}
switch (tok) {
case TNL:
case TEOF:
tokpushback = 1;
/* fall through */
case TBACKGND:
case TSEMI:
break;
default:
if ((nlflag & 1))
raise_error_unexpected_syntax(-1);
tokpushback = 1;
return n1;
}
}
}
static union node *
andor(void)
{
union node *n1, *n2, *n3;
int t;
n1 = pipeline();
for (;;) {
t = readtoken();
if (t == TAND) {
t = NAND;
} else if (t == TOR) {
t = NOR;
} else {
tokpushback = 1;
return n1;
}
checkkwd = CHKNL | CHKKWD | CHKALIAS;
n2 = pipeline();
n3 = stzalloc(sizeof(struct nbinary));
n3->type = t;
n3->nbinary.ch1 = n1;
n3->nbinary.ch2 = n2;
n1 = n3;
}
}
static union node *
pipeline(void)
{
union node *n1, *n2, *pipenode;
struct nodelist *lp, *prev;
int negate;
negate = 0;
TRACE(("pipeline: entered\n"));
if (readtoken() == TNOT) {
negate = !negate;
checkkwd = CHKKWD | CHKALIAS;
} else
tokpushback = 1;
n1 = parse_command();
if (readtoken() == TPIPE) {
pipenode = stzalloc(sizeof(struct npipe));
pipenode->type = NPIPE;
/*pipenode->npipe.pipe_backgnd = 0; - stzalloc did it */
lp = stzalloc(sizeof(struct nodelist));
pipenode->npipe.cmdlist = lp;
lp->n = n1;
do {
prev = lp;
lp = stzalloc(sizeof(struct nodelist));
checkkwd = CHKNL | CHKKWD | CHKALIAS;
lp->n = parse_command();
prev->next = lp;
} while (readtoken() == TPIPE);
lp->next = NULL;
n1 = pipenode;
}
tokpushback = 1;
if (negate) {
n2 = stzalloc(sizeof(struct nnot));
n2->type = NNOT;
n2->nnot.com = n1;
return n2;
}
return n1;
}
static union node *
makename(void)
{
union node *n;
n = stzalloc(sizeof(struct narg));
n->type = NARG;
/*n->narg.next = NULL; - stzalloc did it */
n->narg.text = wordtext;
n->narg.backquote = backquotelist;
return n;
}
static void
fixredir(union node *n, const char *text, int err)
{
int fd;
TRACE(("Fix redir %s %d\n", text, err));
if (!err)
n->ndup.vname = NULL;
fd = bb_strtou(text, NULL, 10);
if (!errno && fd >= 0)
n->ndup.dupfd = fd;
else if (LONE_DASH(text))
n->ndup.dupfd = -1;
else {
if (err)
raise_error_syntax("bad fd number");
n->ndup.vname = makename();
}
}
/*
* Returns true if the text contains nothing to expand (no dollar signs
* or backquotes).
*/
static int
noexpand(const char *text)
{
unsigned char c;
while ((c = *text++) != '\0') {
if (c == CTLQUOTEMARK)
continue;
if (c == CTLESC)
text++;
else if (SIT(c, BASESYNTAX) == CCTL)
return 0;
}
return 1;
}
static void
parsefname(void)
{
union node *n = redirnode;
if (readtoken() != TWORD)
raise_error_unexpected_syntax(-1);
if (n->type == NHERE) {
struct heredoc *here = heredoc;
struct heredoc *p;
int i;
if (quoteflag == 0)
n->type = NXHERE;
TRACE(("Here document %d\n", n->type));
if (!noexpand(wordtext) || (i = strlen(wordtext)) == 0 || i > EOFMARKLEN)
raise_error_syntax("illegal eof marker for << redirection");
rmescapes(wordtext, 0);
here->eofmark = wordtext;
here->next = NULL;
if (heredoclist == NULL)
heredoclist = here;
else {
for (p = heredoclist; p->next; p = p->next)
continue;
p->next = here;
}
} else if (n->type == NTOFD || n->type == NFROMFD) {
fixredir(n, wordtext, 0);
} else {
n->nfile.fname = makename();
}
}
static union node *
simplecmd(void)
{
union node *args, **app;
union node *n = NULL;
union node *vars, **vpp;
union node **rpp, *redir;
int savecheckkwd;
#if ENABLE_ASH_BASH_COMPAT
smallint double_brackets_flag = 0;
smallint function_flag = 0;
#endif
args = NULL;
app = &args;
vars = NULL;
vpp = &vars;
redir = NULL;
rpp = &redir;
savecheckkwd = CHKALIAS;
for (;;) {
int t;
checkkwd = savecheckkwd;
t = readtoken();
switch (t) {
#if ENABLE_ASH_BASH_COMPAT
case TFUNCTION:
if (peektoken() != TWORD)
raise_error_unexpected_syntax(TWORD);
function_flag = 1;
break;
case TAND: /* "&&" */
case TOR: /* "||" */
if (!double_brackets_flag) {
tokpushback = 1;
goto out;
}
wordtext = (char *) (t == TAND ? "-a" : "-o");
#endif
case TWORD:
n = stzalloc(sizeof(struct narg));
n->type = NARG;
/*n->narg.next = NULL; - stzalloc did it */
n->narg.text = wordtext;
#if ENABLE_ASH_BASH_COMPAT
if (strcmp("[[", wordtext) == 0)
double_brackets_flag = 1;
else if (strcmp("]]", wordtext) == 0)
double_brackets_flag = 0;
#endif
n->narg.backquote = backquotelist;
if (savecheckkwd && isassignment(wordtext)) {
*vpp = n;
vpp = &n->narg.next;
} else {
*app = n;
app = &n->narg.next;
savecheckkwd = 0;
}
#if ENABLE_ASH_BASH_COMPAT
if (function_flag) {
checkkwd = CHKNL | CHKKWD;
switch (peektoken()) {
case TBEGIN:
case TIF:
case TCASE:
case TUNTIL:
case TWHILE:
case TFOR:
goto do_func;
case TLP:
function_flag = 0;
break;
case TWORD:
if (strcmp("[[", wordtext) == 0)
goto do_func;
/* fall through */
default:
raise_error_unexpected_syntax(-1);
}
}
#endif
break;
case TREDIR:
*rpp = n = redirnode;
rpp = &n->nfile.next;
parsefname(); /* read name of redirection file */
break;
case TLP:
IF_ASH_BASH_COMPAT(do_func:)
if (args && app == &args->narg.next
&& !vars && !redir
) {
struct builtincmd *bcmd;
const char *name;
/* We have a function */
if (IF_ASH_BASH_COMPAT(!function_flag &&) readtoken() != TRP)
raise_error_unexpected_syntax(TRP);
name = n->narg.text;
if (!goodname(name)
|| ((bcmd = find_builtin(name)) && IS_BUILTIN_SPECIAL(bcmd))
) {
raise_error_syntax("bad function name");
}
n->type = NDEFUN;
checkkwd = CHKNL | CHKKWD | CHKALIAS;
n->narg.next = parse_command();
return n;
}
IF_ASH_BASH_COMPAT(function_flag = 0;)
/* fall through */
default:
tokpushback = 1;
goto out;
}
}
out:
*app = NULL;
*vpp = NULL;
*rpp = NULL;
n = stzalloc(sizeof(struct ncmd));
n->type = NCMD;
n->ncmd.args = args;
n->ncmd.assign = vars;
n->ncmd.redirect = redir;
return n;
}
static union node *
parse_command(void)
{
union node *n1, *n2;
union node *ap, **app;
union node *cp, **cpp;
union node *redir, **rpp;
union node **rpp2;
int t;
redir = NULL;
rpp2 = &redir;
switch (readtoken()) {
default:
raise_error_unexpected_syntax(-1);
/* NOTREACHED */
case TIF:
n1 = stzalloc(sizeof(struct nif));
n1->type = NIF;
n1->nif.test = list(0);
if (readtoken() != TTHEN)
raise_error_unexpected_syntax(TTHEN);
n1->nif.ifpart = list(0);
n2 = n1;
while (readtoken() == TELIF) {
n2->nif.elsepart = stzalloc(sizeof(struct nif));
n2 = n2->nif.elsepart;
n2->type = NIF;
n2->nif.test = list(0);
if (readtoken() != TTHEN)
raise_error_unexpected_syntax(TTHEN);
n2->nif.ifpart = list(0);
}
if (lasttoken == TELSE)
n2->nif.elsepart = list(0);
else {
n2->nif.elsepart = NULL;
tokpushback = 1;
}
t = TFI;
break;
case TWHILE:
case TUNTIL: {
int got;
n1 = stzalloc(sizeof(struct nbinary));
n1->type = (lasttoken == TWHILE) ? NWHILE : NUNTIL;
n1->nbinary.ch1 = list(0);
got = readtoken();
if (got != TDO) {
TRACE(("expecting DO got '%s' %s\n", tokname_array[got],
got == TWORD ? wordtext : ""));
raise_error_unexpected_syntax(TDO);
}
n1->nbinary.ch2 = list(0);
t = TDONE;
break;
}
case TFOR:
if (readtoken() != TWORD || quoteflag || !goodname(wordtext))
raise_error_syntax("bad for loop variable");
n1 = stzalloc(sizeof(struct nfor));
n1->type = NFOR;
n1->nfor.var = wordtext;
checkkwd = CHKNL | CHKKWD | CHKALIAS;
if (readtoken() == TIN) {
app = &ap;
while (readtoken() == TWORD) {
n2 = stzalloc(sizeof(struct narg));
n2->type = NARG;
/*n2->narg.next = NULL; - stzalloc did it */
n2->narg.text = wordtext;
n2->narg.backquote = backquotelist;
*app = n2;
app = &n2->narg.next;
}
*app = NULL;
n1->nfor.args = ap;
if (lasttoken != TNL && lasttoken != TSEMI)
raise_error_unexpected_syntax(-1);
} else {
n2 = stzalloc(sizeof(struct narg));
n2->type = NARG;
/*n2->narg.next = NULL; - stzalloc did it */
n2->narg.text = (char *)dolatstr;
/*n2->narg.backquote = NULL;*/
n1->nfor.args = n2;
/*
* Newline or semicolon here is optional (but note
* that the original Bourne shell only allowed NL).
*/
if (lasttoken != TSEMI)
tokpushback = 1;
}
checkkwd = CHKNL | CHKKWD | CHKALIAS;
if (readtoken() != TDO)
raise_error_unexpected_syntax(TDO);
n1->nfor.body = list(0);
t = TDONE;
break;
case TCASE:
n1 = stzalloc(sizeof(struct ncase));
n1->type = NCASE;
if (readtoken() != TWORD)
raise_error_unexpected_syntax(TWORD);
n1->ncase.expr = n2 = stzalloc(sizeof(struct narg));
n2->type = NARG;
/*n2->narg.next = NULL; - stzalloc did it */
n2->narg.text = wordtext;
n2->narg.backquote = backquotelist;
checkkwd = CHKNL | CHKKWD | CHKALIAS;
if (readtoken() != TIN)
raise_error_unexpected_syntax(TIN);
cpp = &n1->ncase.cases;
next_case:
checkkwd = CHKNL | CHKKWD;
t = readtoken();
while (t != TESAC) {
if (lasttoken == TLP)
readtoken();
*cpp = cp = stzalloc(sizeof(struct nclist));
cp->type = NCLIST;
app = &cp->nclist.pattern;
for (;;) {
*app = ap = stzalloc(sizeof(struct narg));
ap->type = NARG;
/*ap->narg.next = NULL; - stzalloc did it */
ap->narg.text = wordtext;
ap->narg.backquote = backquotelist;
if (readtoken() != TPIPE)
break;
app = &ap->narg.next;
readtoken();
}
//ap->narg.next = NULL;
if (lasttoken != TRP)
raise_error_unexpected_syntax(TRP);
cp->nclist.body = list(2);
cpp = &cp->nclist.next;
checkkwd = CHKNL | CHKKWD;
t = readtoken();
if (t != TESAC) {
if (t != TENDCASE)
raise_error_unexpected_syntax(TENDCASE);
goto next_case;
}
}
*cpp = NULL;
goto redir;
case TLP:
n1 = stzalloc(sizeof(struct nredir));
n1->type = NSUBSHELL;
n1->nredir.n = list(0);
/*n1->nredir.redirect = NULL; - stzalloc did it */
t = TRP;
break;
case TBEGIN:
n1 = list(0);
t = TEND;
break;
IF_ASH_BASH_COMPAT(case TFUNCTION:)
case TWORD:
case TREDIR:
tokpushback = 1;
return simplecmd();
}
if (readtoken() != t)
raise_error_unexpected_syntax(t);
redir:
/* Now check for redirection which may follow command */
checkkwd = CHKKWD | CHKALIAS;
rpp = rpp2;
while (readtoken() == TREDIR) {
*rpp = n2 = redirnode;
rpp = &n2->nfile.next;
parsefname();
}
tokpushback = 1;
*rpp = NULL;
if (redir) {
if (n1->type != NSUBSHELL) {
n2 = stzalloc(sizeof(struct nredir));
n2->type = NREDIR;
n2->nredir.n = n1;
n1 = n2;
}
n1->nredir.redirect = redir;
}
return n1;
}
#if ENABLE_ASH_BASH_COMPAT
static int
decode_dollar_squote(void)
{
static const char C_escapes[] ALIGN1 = "nrbtfav""x\\01234567";
int c, cnt;
char *p;
char buf[4];
c = pgetc();
p = strchr(C_escapes, c);
if (p) {
buf[0] = c;
p = buf;
cnt = 3;
if ((unsigned char)(c - '0') <= 7) { /* \ooo */
do {
c = pgetc();
*++p = c;
} while ((unsigned char)(c - '0') <= 7 && --cnt);
pungetc();
} else if (c == 'x') { /* \xHH */
do {
c = pgetc();
*++p = c;
} while (isxdigit(c) && --cnt);
pungetc();
if (cnt == 3) { /* \x but next char is "bad" */
c = 'x';
goto unrecognized;
}
} else { /* simple seq like \\ or \t */
p++;
}
*p = '\0';
p = buf;
c = bb_process_escape_sequence((void*)&p);
} else { /* unrecognized "\z": print both chars unless ' or " */
if (c != '\'' && c != '"') {
unrecognized:
c |= 0x100; /* "please encode \, then me" */
}
}
return c;
}
#endif
/*
* If eofmark is NULL, read a word or a redirection symbol. If eofmark
* is not NULL, read a here document. In the latter case, eofmark is the
* word which marks the end of the document and striptabs is true if
* leading tabs should be stripped from the document. The argument c
* is the first character of the input token or document.
*
* Because C does not have internal subroutines, I have simulated them
* using goto's to implement the subroutine linkage. The following macros
* will run code that appears at the end of readtoken1.
*/
#define CHECKEND() {goto checkend; checkend_return:;}
#define PARSEREDIR() {goto parseredir; parseredir_return:;}
#define PARSESUB() {goto parsesub; parsesub_return:;}
#define PARSEBACKQOLD() {oldstyle = 1; goto parsebackq; parsebackq_oldreturn:;}
#define PARSEBACKQNEW() {oldstyle = 0; goto parsebackq; parsebackq_newreturn:;}
#define PARSEARITH() {goto parsearith; parsearith_return:;}
static int
readtoken1(int c, int syntax, char *eofmark, int striptabs)
{
/* NB: syntax parameter fits into smallint */
/* c parameter is an unsigned char or PEOF or PEOA */
char *out;
size_t len;
char line[EOFMARKLEN + 1];
struct nodelist *bqlist;
smallint quotef;
smallint dblquote;
smallint oldstyle;
IF_FEATURE_SH_MATH(smallint prevsyntax;) /* syntax before arithmetic */
#if ENABLE_ASH_EXPAND_PRMT
smallint pssyntax; /* we are expanding a prompt string */
#endif
int varnest; /* levels of variables expansion */
IF_FEATURE_SH_MATH(int arinest;) /* levels of arithmetic expansion */
IF_FEATURE_SH_MATH(int parenlevel;) /* levels of parens in arithmetic */
int dqvarnest; /* levels of variables expansion within double quotes */
IF_ASH_BASH_COMPAT(smallint bash_dollar_squote = 0;)
startlinno = g_parsefile->linno;
bqlist = NULL;
quotef = 0;
IF_FEATURE_SH_MATH(prevsyntax = 0;)
#if ENABLE_ASH_EXPAND_PRMT
pssyntax = (syntax == PSSYNTAX);
if (pssyntax)
syntax = DQSYNTAX;
#endif
dblquote = (syntax == DQSYNTAX);
varnest = 0;
IF_FEATURE_SH_MATH(arinest = 0;)
IF_FEATURE_SH_MATH(parenlevel = 0;)
dqvarnest = 0;
STARTSTACKSTR(out);
loop:
/* For each line, until end of word */
CHECKEND(); /* set c to PEOF if at end of here document */
for (;;) { /* until end of line or end of word */
CHECKSTRSPACE(4, out); /* permit 4 calls to USTPUTC */
switch (SIT(c, syntax)) {
case CNL: /* '\n' */
if (syntax == BASESYNTAX)
goto endword; /* exit outer loop */
USTPUTC(c, out);
nlprompt();
c = pgetc();
goto loop; /* continue outer loop */
case CWORD:
USTPUTC(c, out);
break;
case CCTL:
#if ENABLE_ASH_BASH_COMPAT
if (c == '\\' && bash_dollar_squote) {
c = decode_dollar_squote();
if (c == '\0') {
/* skip $'\000', $'\x00' (like bash) */
break;
}
if (c & 0x100) {
/* Unknown escape. Encode as '\z' */
c = (unsigned char)c;
if (eofmark == NULL || dblquote)
USTPUTC(CTLESC, out);
USTPUTC('\\', out);
}
}
#endif
if (eofmark == NULL || dblquote)
USTPUTC(CTLESC, out);
USTPUTC(c, out);
break;
case CBACK: /* backslash */
c = pgetc_without_PEOA();
if (c == PEOF) {
USTPUTC(CTLESC, out);
USTPUTC('\\', out);
pungetc();
} else if (c == '\n') {
nlprompt();
} else {
#if ENABLE_ASH_EXPAND_PRMT
if (c == '$' && pssyntax) {
USTPUTC(CTLESC, out);
USTPUTC('\\', out);
}
#endif
/* Backslash is retained if we are in "str" and next char isn't special */
if (dblquote
&& c != '\\'
&& c != '`'
&& c != '$'
&& (c != '"' || eofmark != NULL)
) {
USTPUTC('\\', out);
}
USTPUTC(CTLESC, out);
USTPUTC(c, out);
quotef = 1;
}
break;
case CSQUOTE:
syntax = SQSYNTAX;
quotemark:
if (eofmark == NULL) {
USTPUTC(CTLQUOTEMARK, out);
}
break;
case CDQUOTE:
syntax = DQSYNTAX;
dblquote = 1;
goto quotemark;
case CENDQUOTE:
IF_ASH_BASH_COMPAT(bash_dollar_squote = 0;)
if (eofmark != NULL && varnest == 0) {
USTPUTC(c, out);
} else {
if (dqvarnest == 0) {
syntax = BASESYNTAX;
dblquote = 0;
}
quotef = 1;
goto quotemark;
}
break;
case CVAR: /* '$' */
PARSESUB(); /* parse substitution */
break;
case CENDVAR: /* '}' */
if (varnest > 0) {
varnest--;
if (dqvarnest > 0) {
dqvarnest--;
}
c = CTLENDVAR;
}
USTPUTC(c, out);
break;
#if ENABLE_FEATURE_SH_MATH
case CLP: /* '(' in arithmetic */
parenlevel++;
USTPUTC(c, out);
break;
case CRP: /* ')' in arithmetic */
if (parenlevel > 0) {
parenlevel--;
} else {
if (pgetc_eatbnl() == ')') {
c = CTLENDARI;
if (--arinest == 0) {
syntax = prevsyntax;
}
} else {
/*
* unbalanced parens
* (don't 2nd guess - no error)
*/
pungetc();
}
}
USTPUTC(c, out);
break;
#endif
case CBQUOTE: /* '`' */
PARSEBACKQOLD();
break;
case CENDFILE:
goto endword; /* exit outer loop */
case CIGN:
break;
default:
if (varnest == 0) {
#if ENABLE_ASH_BASH_COMPAT
if (c == '&') {
//Can't call pgetc_eatbnl() here, this requires three-deep pungetc()
if (pgetc() == '>')
c = 0x100 + '>'; /* flag &> */
pungetc();
}
#endif
goto endword; /* exit outer loop */
}
IF_ASH_ALIAS(if (c != PEOA))
USTPUTC(c, out);
}
c = pgetc();
} /* for (;;) */
endword:
#if ENABLE_FEATURE_SH_MATH
if (syntax == ARISYNTAX)
raise_error_syntax("missing '))'");
#endif
if (syntax != BASESYNTAX && eofmark == NULL)
raise_error_syntax("unterminated quoted string");
if (varnest != 0) {
startlinno = g_parsefile->linno;
/* { */
raise_error_syntax("missing '}'");
}
USTPUTC('\0', out);
len = out - (char *)stackblock();
out = stackblock();
if (eofmark == NULL) {
if ((c == '>' || c == '<' IF_ASH_BASH_COMPAT( || c == 0x100 + '>'))
&& quotef == 0
) {
if (isdigit_str9(out)) {
PARSEREDIR(); /* passed as params: out, c */
lasttoken = TREDIR;
return lasttoken;
}
/* else: non-number X seen, interpret it
* as "NNNX>file" = "NNNX >file" */
}
pungetc();
}
quoteflag = quotef;
backquotelist = bqlist;
grabstackblock(len);
wordtext = out;
lasttoken = TWORD;
return lasttoken;
/* end of readtoken routine */
/*
* Check to see whether we are at the end of the here document. When this
* is called, c is set to the first character of the next input line. If
* we are at the end of the here document, this routine sets the c to PEOF.
*/
checkend: {
if (eofmark) {
#if ENABLE_ASH_ALIAS
if (c == PEOA)
c = pgetc_without_PEOA();
#endif
if (striptabs) {
while (c == '\t') {
c = pgetc_without_PEOA();
}
}
if (c == *eofmark) {
if (pfgets(line, sizeof(line)) != NULL) {
char *p, *q;
int cc;
p = line;
for (q = eofmark + 1;; p++, q++) {
cc = *p;
if (cc == '\n')
cc = 0;
if (!*q || cc != *q)
break;
}
if (cc == *q) {
c = PEOF;
nlnoprompt();
} else {
pushstring(line, NULL);
}
}
}
}
goto checkend_return;
}
/*
* Parse a redirection operator. The variable "out" points to a string
* specifying the fd to be redirected. The variable "c" contains the
* first character of the redirection operator.
*/
parseredir: {
/* out is already checked to be a valid number or "" */
int fd = (*out == '\0' ? -1 : atoi(out));
union node *np;
np = stzalloc(sizeof(struct nfile));
if (c == '>') {
np->nfile.fd = 1;
c = pgetc();
if (c == '>')
np->type = NAPPEND;
else if (c == '|')
np->type = NCLOBBER;
else if (c == '&')
np->type = NTOFD;
/* it also can be NTO2 (>&file), but we can't figure it out yet */
else {
np->type = NTO;
pungetc();
}
}
#if ENABLE_ASH_BASH_COMPAT
else if (c == 0x100 + '>') { /* this flags &> redirection */
np->nfile.fd = 1;
pgetc(); /* this is '>', no need to check */
np->type = NTO2;
}
#endif
else { /* c == '<' */
/*np->nfile.fd = 0; - stzalloc did it */
c = pgetc();
switch (c) {
case '<':
if (sizeof(struct nfile) != sizeof(struct nhere)) {
np = stzalloc(sizeof(struct nhere));
/*np->nfile.fd = 0; - stzalloc did it */
}
np->type = NHERE;
heredoc = stzalloc(sizeof(struct heredoc));
heredoc->here = np;
c = pgetc();
if (c == '-') {
heredoc->striptabs = 1;
} else {
/*heredoc->striptabs = 0; - stzalloc did it */
pungetc();
}
break;
case '&':
np->type = NFROMFD;
break;
case '>':
np->type = NFROMTO;
break;
default:
np->type = NFROM;
pungetc();
break;
}
}
if (fd >= 0)
np->nfile.fd = fd;
redirnode = np;
goto parseredir_return;
}
/*
* Parse a substitution. At this point, we have read the dollar sign
* and nothing else.
*/
/* is_special(c) evaluates to 1 for c in "!#$*-0123456789?@"; 0 otherwise
* (assuming ascii char codes, as the original implementation did) */
#define is_special(c) \
(((unsigned)(c) - 33 < 32) \
&& ((0xc1ff920dU >> ((unsigned)(c) - 33)) & 1))
parsesub: {
unsigned char subtype;
int typeloc;
c = pgetc_eatbnl();
if (c > 255 /* PEOA or PEOF */
|| (c != '(' && c != '{' && !is_name(c) && !is_special(c))
) {
#if ENABLE_ASH_BASH_COMPAT
if (syntax != DQSYNTAX && c == '\'')
bash_dollar_squote = 1;
else
#endif
USTPUTC('$', out);
pungetc();
} else if (c == '(') {
/* $(command) or $((arith)) */
if (pgetc_eatbnl() == '(') {
#if ENABLE_FEATURE_SH_MATH
PARSEARITH();
#else
raise_error_syntax("you disabled math support for $((arith)) syntax");
#endif
} else {
pungetc();
PARSEBACKQNEW();
}
} else {
/* $VAR, $<specialchar>, ${...}, or PEOA/PEOF */
USTPUTC(CTLVAR, out);
typeloc = out - (char *)stackblock();
STADJUST(1, out);
subtype = VSNORMAL;
if (c == '{') {
c = pgetc_eatbnl();
subtype = 0;
}
varname:
if (is_name(c)) {
/* $[{[#]]NAME[}] */
do {
STPUTC(c, out);
c = pgetc_eatbnl();
} while (is_in_name(c));
} else if (isdigit(c)) {
/* $[{[#]]NUM[}] */
do {
STPUTC(c, out);
c = pgetc_eatbnl();
} while (isdigit(c));
} else if (is_special(c)) {
/* $[{[#]]<specialchar>[}] */
int cc = c;
c = pgetc_eatbnl();
if (!subtype && cc == '#') {
subtype = VSLENGTH;
if (c == '_' || isalnum(c))
goto varname;
cc = c;
c = pgetc_eatbnl();
if (cc == '}' || c != '}') {
pungetc();
subtype = 0;
c = cc;
cc = '#';
}
}
USTPUTC(cc, out);
} else {
goto badsub;
}
if (c != '}' && subtype == VSLENGTH) {
/* ${#VAR didn't end with } */
goto badsub;
}
if (subtype == 0) {
static const char types[] ALIGN1 = "}-+?=";
/* ${VAR...} but not $VAR or ${#VAR} */
/* c == first char after VAR */
switch (c) {
case ':':
c = pgetc_eatbnl();
#if ENABLE_ASH_BASH_COMPAT
/* This check is only needed to not misinterpret
* ${VAR:-WORD}, ${VAR:+WORD}, ${VAR:=WORD}, ${VAR:?WORD}
* constructs.
*/
if (!strchr(types, c)) {
subtype = VSSUBSTR;
pungetc();
break; /* "goto badsub" is bigger (!) */
}
#endif
subtype = VSNUL;
/*FALLTHROUGH*/
default: {
const char *p = strchr(types, c);
if (p == NULL)
break;
subtype |= p - types + VSNORMAL;
break;
}
case '%':
case '#': {
int cc = c;
subtype = (c == '#' ? VSTRIMLEFT : VSTRIMRIGHT);
c = pgetc_eatbnl();
if (c != cc)
goto badsub;
subtype++;
break;
}
#if ENABLE_ASH_BASH_COMPAT
case '/':
/* ${v/[/]pattern/repl} */
//TODO: encode pattern and repl separately.
// Currently ${v/$var_with_slash/repl} is horribly broken
subtype = VSREPLACE;
c = pgetc_eatbnl();
if (c != '/')
goto badsub;
subtype++; /* VSREPLACEALL */
break;
#endif
}
} else {
badsub:
pungetc();
}
((unsigned char *)stackblock())[typeloc] = subtype;
if (subtype != VSNORMAL) {
varnest++;
if (dblquote)
dqvarnest++;
}
STPUTC('=', out);
}
goto parsesub_return;
}
/*
* Called to parse command substitutions. Newstyle is set if the command
* is enclosed inside $(...); nlpp is a pointer to the head of the linked
* list of commands (passed by reference), and savelen is the number of
* characters on the top of the stack which must be preserved.
*/
parsebackq: {
struct nodelist **nlpp;
union node *n;
char *str;
size_t savelen;
smallint saveprompt = 0;
str = NULL;
savelen = out - (char *)stackblock();
if (savelen > 0) {
/*
* FIXME: this can allocate very large block on stack and SEGV.
* Example:
* echo "..<100kbytes>..`true` $(true) `true` ..."
* allocates 100kb for every command subst. With about
* a hundred command substitutions stack overflows.
* With larger prepended string, SEGV happens sooner.
*/
str = alloca(savelen);
memcpy(str, stackblock(), savelen);
}
if (oldstyle) {
/* We must read until the closing backquote, giving special
* treatment to some slashes, and then push the string and
* reread it as input, interpreting it normally.
*/
char *pout;
size_t psavelen;
char *pstr;
STARTSTACKSTR(pout);
for (;;) {
int pc;
setprompt_if(needprompt, 2);
pc = pgetc();
switch (pc) {
case '`':
goto done;
case '\\':
pc = pgetc();
if (pc == '\n') {
nlprompt();
/*
* If eating a newline, avoid putting
* the newline into the new character
* stream (via the STPUTC after the
* switch).
*/
continue;
}
if (pc != '\\' && pc != '`' && pc != '$'
&& (!dblquote || pc != '"')
) {
STPUTC('\\', pout);
}
if (pc <= 255 /* not PEOA or PEOF */) {
break;
}
/* fall through */
case PEOF:
IF_ASH_ALIAS(case PEOA:)
startlinno = g_parsefile->linno;
raise_error_syntax("EOF in backquote substitution");
case '\n':
nlnoprompt();
break;
default:
break;
}
STPUTC(pc, pout);
}
done:
STPUTC('\0', pout);
psavelen = pout - (char *)stackblock();
if (psavelen > 0) {
pstr = grabstackstr(pout);
setinputstring(pstr);
}
}
nlpp = &bqlist;
while (*nlpp)
nlpp = &(*nlpp)->next;
*nlpp = stzalloc(sizeof(**nlpp));
/* (*nlpp)->next = NULL; - stzalloc did it */
if (oldstyle) {
saveprompt = doprompt;
doprompt = 0;
}
n = list(2);
if (oldstyle)
doprompt = saveprompt;
else if (readtoken() != TRP)
raise_error_unexpected_syntax(TRP);
(*nlpp)->n = n;
if (oldstyle) {
/*
* Start reading from old file again, ignoring any pushed back
* tokens left from the backquote parsing
*/
popfile();
tokpushback = 0;
}
while (stackblocksize() <= savelen)
growstackblock();
STARTSTACKSTR(out);
if (str) {
memcpy(out, str, savelen);
STADJUST(savelen, out);
}
USTPUTC(CTLBACKQ, out);
if (oldstyle)
goto parsebackq_oldreturn;
goto parsebackq_newreturn;
}
#if ENABLE_FEATURE_SH_MATH
/*
* Parse an arithmetic expansion (indicate start of one and set state)
*/
parsearith: {
if (++arinest == 1) {
prevsyntax = syntax;
syntax = ARISYNTAX;
}
USTPUTC(CTLARI, out);
goto parsearith_return;
}
#endif
} /* end of readtoken */
/*
* Read the next input token.
* If the token is a word, we set backquotelist to the list of cmds in
* backquotes. We set quoteflag to true if any part of the word was
* quoted.
* If the token is TREDIR, then we set redirnode to a structure containing
* the redirection.
* In all cases, the variable startlinno is set to the number of the line
* on which the token starts.
*
* [Change comment: here documents and internal procedures]
* [Readtoken shouldn't have any arguments. Perhaps we should make the
* word parsing code into a separate routine. In this case, readtoken
* doesn't need to have any internal procedures, but parseword does.
* We could also make parseoperator in essence the main routine, and
* have parseword (readtoken1?) handle both words and redirection.]
*/
#define NEW_xxreadtoken
#ifdef NEW_xxreadtoken
/* singles must be first! */
static const char xxreadtoken_chars[7] ALIGN1 = {
'\n', '(', ')', /* singles */
'&', '|', ';', /* doubles */
0
};
#define xxreadtoken_singles 3
#define xxreadtoken_doubles 3
static const char xxreadtoken_tokens[] ALIGN1 = {
TNL, TLP, TRP, /* only single occurrence allowed */
TBACKGND, TPIPE, TSEMI, /* if single occurrence */
TEOF, /* corresponds to trailing nul */
TAND, TOR, TENDCASE /* if double occurrence */
};
static int
xxreadtoken(void)
{
int c;
if (tokpushback) {
tokpushback = 0;
return lasttoken;
}
setprompt_if(needprompt, 2);
startlinno = g_parsefile->linno;
for (;;) { /* until token or start of word found */
c = pgetc();
if (c == ' ' || c == '\t' IF_ASH_ALIAS( || c == PEOA))
continue;
if (c == '#') {
while ((c = pgetc()) != '\n' && c != PEOF)
continue;
pungetc();
} else if (c == '\\') {
if (pgetc() != '\n') {
pungetc();
break; /* return readtoken1(...) */
}
nlprompt();
} else {
const char *p;
p = xxreadtoken_chars + sizeof(xxreadtoken_chars) - 1;
if (c != PEOF) {
if (c == '\n') {
nlnoprompt();
}
p = strchr(xxreadtoken_chars, c);
if (p == NULL)
break; /* return readtoken1(...) */
if ((int)(p - xxreadtoken_chars) >= xxreadtoken_singles) {
int cc = pgetc();
if (cc == c) { /* double occurrence? */
p += xxreadtoken_doubles + 1;
} else {
pungetc();
#if ENABLE_ASH_BASH_COMPAT
if (c == '&' && cc == '>') /* &> */
break; /* return readtoken1(...) */
#endif
}
}
}
lasttoken = xxreadtoken_tokens[p - xxreadtoken_chars];
return lasttoken;
}
} /* for (;;) */
return readtoken1(c, BASESYNTAX, (char *) NULL, 0);
}
#else /* old xxreadtoken */
#define RETURN(token) return lasttoken = token
static int
xxreadtoken(void)
{
int c;
if (tokpushback) {
tokpushback = 0;
return lasttoken;
}
setprompt_if(needprompt, 2);
startlinno = g_parsefile->linno;
for (;;) { /* until token or start of word found */
c = pgetc();
switch (c) {
case ' ': case '\t':
IF_ASH_ALIAS(case PEOA:)
continue;
case '#':
while ((c = pgetc()) != '\n' && c != PEOF)
continue;
pungetc();
continue;
case '\\':
if (pgetc() == '\n') {
nlprompt();
continue;
}
pungetc();
goto breakloop;
case '\n':
nlnoprompt();
RETURN(TNL);
case PEOF:
RETURN(TEOF);
case '&':
if (pgetc() == '&')
RETURN(TAND);
pungetc();
RETURN(TBACKGND);
case '|':
if (pgetc() == '|')
RETURN(TOR);
pungetc();
RETURN(TPIPE);
case ';':
if (pgetc() == ';')
RETURN(TENDCASE);
pungetc();
RETURN(TSEMI);
case '(':
RETURN(TLP);
case ')':
RETURN(TRP);
default:
goto breakloop;
}
}
breakloop:
return readtoken1(c, BASESYNTAX, (char *)NULL, 0);
#undef RETURN
}
#endif /* old xxreadtoken */
static int
readtoken(void)
{
int t;
int kwd = checkkwd;
#if DEBUG
smallint alreadyseen = tokpushback;
#endif
#if ENABLE_ASH_ALIAS
top:
#endif
t = xxreadtoken();
/*
* eat newlines
*/
if (kwd & CHKNL) {
while (t == TNL) {
parseheredoc();
t = xxreadtoken();
}
}
if (t != TWORD || quoteflag) {
goto out;
}
/*
* check for keywords
*/
if (kwd & CHKKWD) {
const char *const *pp;
pp = findkwd(wordtext);
if (pp) {
lasttoken = t = pp - tokname_array;
TRACE(("keyword '%s' recognized\n", tokname_array[t]));
goto out;
}
}
if (checkkwd & CHKALIAS) {
#if ENABLE_ASH_ALIAS
struct alias *ap;
ap = lookupalias(wordtext, 1);
if (ap != NULL) {
if (*ap->val) {
pushstring(ap->val, ap);
}
goto top;
}
#endif
}
out:
checkkwd = 0;
#if DEBUG
if (!alreadyseen)
TRACE(("token '%s' %s\n", tokname_array[t], t == TWORD ? wordtext : ""));
else
TRACE(("reread token '%s' %s\n", tokname_array[t], t == TWORD ? wordtext : ""));
#endif
return t;
}
static int
peektoken(void)
{
int t;
t = readtoken();
tokpushback = 1;
return t;
}
/*
* Read and parse a command. Returns NODE_EOF on end of file.
* (NULL is a valid parse tree indicating a blank line.)
*/
static union node *
parsecmd(int interact)
{
tokpushback = 0;
checkkwd = 0;
heredoclist = 0;
doprompt = interact;
setprompt_if(doprompt, doprompt);
needprompt = 0;
return list(1);
}
/*
* Input any here documents.
*/
static void
parseheredoc(void)
{
struct heredoc *here;
union node *n;
here = heredoclist;
heredoclist = NULL;
while (here) {
setprompt_if(needprompt, 2);
readtoken1(pgetc(), here->here->type == NHERE ? SQSYNTAX : DQSYNTAX,
here->eofmark, here->striptabs);
n = stzalloc(sizeof(struct narg));
n->narg.type = NARG;
/*n->narg.next = NULL; - stzalloc did it */
n->narg.text = wordtext;
n->narg.backquote = backquotelist;
here->here->nhere.doc = n;
here = here->next;
}
}
/*
* called by editline -- any expansions to the prompt should be added here.
*/
#if ENABLE_ASH_EXPAND_PRMT
static const char *
expandstr(const char *ps)
{
union node n;
int saveprompt;
/* XXX Fix (char *) cast. It _is_ a bug. ps is variable's value,
* and token processing _can_ alter it (delete NULs etc). */
setinputstring((char *)ps);
saveprompt = doprompt;
doprompt = 0;
readtoken1(pgetc(), PSSYNTAX, nullstr, 0);
doprompt = saveprompt;
popfile();
n.narg.type = NARG;
n.narg.next = NULL;
n.narg.text = wordtext;
n.narg.backquote = backquotelist;
expandarg(&n, NULL, EXP_QUOTED);
return stackblock();
}
#endif
/*
* Execute a command or commands contained in a string.
*/
static int
evalstring(char *s, int flags)
{
struct jmploc *volatile savehandler;
struct jmploc jmploc;
int ex;
union node *n;
struct stackmark smark;
int status;
s = sstrdup(s);
setinputstring(s);
setstackmark(&smark);
status = 0;
/* On exception inside execution loop, we must popfile().
* Try interactively:
* readonly a=a
* command eval "a=b" # throws "is read only" error
* "command BLTIN" is not supposed to abort (even in non-interactive use).
* But if we skip popfile(), we hit EOF in eval's string, and exit.
*/
savehandler = exception_handler;
ex = setjmp(jmploc.loc);
if (ex)
goto out;
exception_handler = &jmploc;
while ((n = parsecmd(0)) != NODE_EOF) {
int i;
i = evaltree(n, flags);
if (n)
status = i;
popstackmark(&smark);
if (evalskip)
break;
}
out:
popstackmark(&smark);
popfile();
stunalloc(s);
exception_handler = savehandler;
if (ex)
longjmp(exception_handler->loc, ex);
return status;
}
/*
* The eval command.
*/
static int FAST_FUNC
evalcmd(int argc UNUSED_PARAM, char **argv, int flags)
{
char *p;
char *concat;
if (argv[1]) {
p = argv[1];
argv += 2;
if (argv[0]) {
STARTSTACKSTR(concat);
for (;;) {
concat = stack_putstr(p, concat);
p = *argv++;
if (p == NULL)
break;
STPUTC(' ', concat);
}
STPUTC('\0', concat);
p = grabstackstr(concat);
}
return evalstring(p, flags & EV_TESTED);
}
return 0;
}
/*
* Read and execute commands.
* "Top" is nonzero for the top level command loop;
* it turns on prompting if the shell is interactive.
*/
static int
cmdloop(int top)
{
union node *n;
struct stackmark smark;
int inter;
int status = 0;
int numeof = 0;
TRACE(("cmdloop(%d) called\n", top));
for (;;) {
int skip;
setstackmark(&smark);
#if JOBS
if (doing_jobctl)
showjobs(SHOW_CHANGED|SHOW_STDERR);
#endif
inter = 0;
if (iflag && top) {
inter++;
chkmail();
}
n = parsecmd(inter);
#if DEBUG
if (DEBUG > 2 && debug && (n != NODE_EOF))
showtree(n);
#endif
if (n == NODE_EOF) {
if (!top || numeof >= 50)
break;
if (!stoppedjobs()) {
if (!Iflag)
break;
out2str("\nUse \"exit\" to leave shell.\n");
}
numeof++;
} else if (nflag == 0) {
int i;
/* job_warning can only be 2,1,0. Here 2->1, 1/0->0 */
job_warning >>= 1;
numeof = 0;
i = evaltree(n, 0);
if (n)
status = i;
}
popstackmark(&smark);
skip = evalskip;
if (skip) {
evalskip &= ~SKIPFUNC;
break;
}
}
return status;
}
/*
* Take commands from a file. To be compatible we should do a path
* search for the file, which is necessary to find sub-commands.
*/
static char *
find_dot_file(char *name)
{
char *fullname;
const char *path = pathval();
struct stat statb;
/* don't try this for absolute or relative paths */
if (strchr(name, '/'))
return name;
/* IIRC standards do not say whether . is to be searched.
* And it is even smaller this way, making it unconditional for now:
*/
if (1) { /* ENABLE_ASH_BASH_COMPAT */
fullname = name;
goto try_cur_dir;
}
while ((fullname = path_advance(&path, name)) != NULL) {
try_cur_dir:
if ((stat(fullname, &statb) == 0) && S_ISREG(statb.st_mode)) {
/*
* Don't bother freeing here, since it will
* be freed by the caller.
*/
return fullname;
}
if (fullname != name)
stunalloc(fullname);
}
/* not found in the PATH */
ash_msg_and_raise_error("%s: not found", name);
/* NOTREACHED */
}
static int FAST_FUNC
dotcmd(int argc_ UNUSED_PARAM, char **argv_ UNUSED_PARAM)
{
/* "false; . empty_file; echo $?" should print 0, not 1: */
int status = 0;
char *fullname;
char **argv;
struct strlist *sp;
volatile struct shparam saveparam;
for (sp = cmdenviron; sp; sp = sp->next)
setvareq(ckstrdup(sp->text), VSTRFIXED | VTEXTFIXED);
nextopt(nullstr); /* handle possible "--" */
argv = argptr;
if (!argv[0]) {
/* bash says: "bash: .: filename argument required" */
return 2; /* bash compat */
}
/* This aborts if file isn't found, which is POSIXly correct.
* bash returns exitcode 1 instead.
*/
fullname = find_dot_file(argv[0]);
argv++;
if (argv[0]) { /* . FILE ARGS, ARGS exist */
int argc;
saveparam = shellparam;
shellparam.malloced = 0;
argc = 1;
while (argv[argc])
argc++;
shellparam.nparam = argc;
shellparam.p = argv;
};
/* This aborts if file can't be opened, which is POSIXly correct.
* bash returns exitcode 1 instead.
*/
setinputfile(fullname, INPUT_PUSH_FILE);
commandname = fullname;
status = cmdloop(0);
popfile();
if (argv[0]) {
freeparam(&shellparam);
shellparam = saveparam;
};
return status;
}
static int FAST_FUNC
exitcmd(int argc UNUSED_PARAM, char **argv)
{
if (stoppedjobs())
return 0;
if (argv[1])
exitstatus = number(argv[1]);
raise_exception(EXEXIT);
/* NOTREACHED */
}
/*
* Read a file containing shell functions.
*/
static void
readcmdfile(char *name)
{
setinputfile(name, INPUT_PUSH_FILE);
cmdloop(0);
popfile();
}
/* ============ find_command inplementation */
/*
* Resolve a command name. If you change this routine, you may have to
* change the shellexec routine as well.
*/
static void
find_command(char *name, struct cmdentry *entry, int act, const char *path)
{
struct tblentry *cmdp;
int idx;
int prev;
char *fullname;
struct stat statb;
int e;
int updatetbl;
struct builtincmd *bcmd;
/* If name contains a slash, don't use PATH or hash table */
if (strchr(name, '/') != NULL) {
entry->u.index = -1;
if (act & DO_ABS) {
while (stat(name, &statb) < 0) {
#ifdef SYSV
if (errno == EINTR)
continue;
#endif
entry->cmdtype = CMDUNKNOWN;
return;
}
}
entry->cmdtype = CMDNORMAL;
return;
}
/* #if ENABLE_FEATURE_SH_STANDALONE... moved after builtin check */
updatetbl = (path == pathval());
if (!updatetbl) {
act |= DO_ALTPATH;
if (strstr(path, "%builtin") != NULL)
act |= DO_ALTBLTIN;
}
/* If name is in the table, check answer will be ok */
cmdp = cmdlookup(name, 0);
if (cmdp != NULL) {
int bit;
switch (cmdp->cmdtype) {
default:
#if DEBUG
abort();
#endif
case CMDNORMAL:
bit = DO_ALTPATH;
break;
case CMDFUNCTION:
bit = DO_NOFUNC;
break;
case CMDBUILTIN:
bit = DO_ALTBLTIN;
break;
}
if (act & bit) {
updatetbl = 0;
cmdp = NULL;
} else if (cmdp->rehash == 0)
/* if not invalidated by cd, we're done */
goto success;
}
/* If %builtin not in path, check for builtin next */
bcmd = find_builtin(name);
if (bcmd) {
if (IS_BUILTIN_REGULAR(bcmd))
goto builtin_success;
if (act & DO_ALTPATH) {
if (!(act & DO_ALTBLTIN))
goto builtin_success;
} else if (builtinloc <= 0) {
goto builtin_success;
}
}
#if ENABLE_FEATURE_SH_STANDALONE
{
int applet_no = find_applet_by_name(name);
if (applet_no >= 0) {
entry->cmdtype = CMDNORMAL;
entry->u.index = -2 - applet_no;
return;
}
}
#endif
/* We have to search path. */
prev = -1; /* where to start */
if (cmdp && cmdp->rehash) { /* doing a rehash */
if (cmdp->cmdtype == CMDBUILTIN)
prev = builtinloc;
else
prev = cmdp->param.index;
}
e = ENOENT;
idx = -1;
loop:
while ((fullname = path_advance(&path, name)) != NULL) {
stunalloc(fullname);
/* NB: code below will still use fullname
* despite it being "unallocated" */
idx++;
if (pathopt) {
if (prefix(pathopt, "builtin")) {
if (bcmd)
goto builtin_success;
continue;
}
if ((act & DO_NOFUNC)
|| !prefix(pathopt, "func")
) { /* ignore unimplemented options */
continue;
}
}
/* if rehash, don't redo absolute path names */
if (fullname[0] == '/' && idx <= prev) {
if (idx < prev)
continue;
TRACE(("searchexec \"%s\": no change\n", name));
goto success;
}
while (stat(fullname, &statb) < 0) {
#ifdef SYSV
if (errno == EINTR)
continue;
#endif
if (errno != ENOENT && errno != ENOTDIR)
e = errno;
goto loop;
}
e = EACCES; /* if we fail, this will be the error */
if (!S_ISREG(statb.st_mode))
continue;
if (pathopt) { /* this is a %func directory */
stalloc(strlen(fullname) + 1);
/* NB: stalloc will return space pointed by fullname
* (because we don't have any intervening allocations
* between stunalloc above and this stalloc) */
readcmdfile(fullname);
cmdp = cmdlookup(name, 0);
if (cmdp == NULL || cmdp->cmdtype != CMDFUNCTION)
ash_msg_and_raise_error("%s not defined in %s", name, fullname);
stunalloc(fullname);
goto success;
}
TRACE(("searchexec \"%s\" returns \"%s\"\n", name, fullname));
if (!updatetbl) {
entry->cmdtype = CMDNORMAL;
entry->u.index = idx;
return;
}
INT_OFF;
cmdp = cmdlookup(name, 1);
cmdp->cmdtype = CMDNORMAL;
cmdp->param.index = idx;
INT_ON;
goto success;
}
/* We failed. If there was an entry for this command, delete it */
if (cmdp && updatetbl)
delete_cmd_entry();
if (act & DO_ERR)
ash_msg("%s: %s", name, errmsg(e, "not found"));
entry->cmdtype = CMDUNKNOWN;
return;
builtin_success:
if (!updatetbl) {
entry->cmdtype = CMDBUILTIN;
entry->u.cmd = bcmd;
return;
}
INT_OFF;
cmdp = cmdlookup(name, 1);
cmdp->cmdtype = CMDBUILTIN;
cmdp->param.cmd = bcmd;
INT_ON;
success:
cmdp->rehash = 0;
entry->cmdtype = cmdp->cmdtype;
entry->u = cmdp->param;
}
/*
* The trap builtin.
*/
static int FAST_FUNC
trapcmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
char *action;
char **ap;
int signo, exitcode;
nextopt(nullstr);
ap = argptr;
if (!*ap) {
for (signo = 0; signo < NSIG; signo++) {
char *tr = trap_ptr[signo];
if (tr) {
/* note: bash adds "SIG", but only if invoked
* as "bash". If called as "sh", or if set -o posix,
* then it prints short signal names.
* We are printing short names: */
out1fmt("trap -- %s %s\n",
single_quote(tr),
get_signame(signo));
/* trap_ptr != trap only if we are in special-cased `trap` code.
* In this case, we will exit very soon, no need to free(). */
/* if (trap_ptr != trap && tp[0]) */
/* free(tr); */
}
}
/*
if (trap_ptr != trap) {
free(trap_ptr);
trap_ptr = trap;
}
*/
return 0;
}
action = NULL;
if (ap[1])
action = *ap++;
exitcode = 0;
while (*ap) {
signo = get_signum(*ap);
if (signo < 0) {
/* Mimic bash message exactly */
ash_msg("%s: invalid signal specification", *ap);
exitcode = 1;
goto next;
}
INT_OFF;
if (action) {
if (LONE_DASH(action))
action = NULL;
else {
if (action[0]) /* not NULL and not "" and not "-" */
may_have_traps = 1;
action = ckstrdup(action);
}
}
free(trap[signo]);
trap[signo] = action;
if (signo != 0)
setsignal(signo);
INT_ON;
next:
ap++;
}
return exitcode;
}
/* ============ Builtins */
#if ENABLE_ASH_HELP
static int FAST_FUNC
helpcmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
unsigned col;
unsigned i;
out1fmt(
"Built-in commands:\n"
"------------------\n");
for (col = 0, i = 0; i < ARRAY_SIZE(builtintab); i++) {
col += out1fmt("%c%s", ((col == 0) ? '\t' : ' '),
builtintab[i].name + 1);
if (col > 60) {
out1fmt("\n");
col = 0;
}
}
# if ENABLE_FEATURE_SH_STANDALONE
{
const char *a = applet_names;
while (*a) {
col += out1fmt("%c%s", ((col == 0) ? '\t' : ' '), a);
if (col > 60) {
out1fmt("\n");
col = 0;
}
while (*a++ != '\0')
continue;
}
}
# endif
newline_and_flush(stdout);
return EXIT_SUCCESS;
}
#endif
#if MAX_HISTORY
static int FAST_FUNC
historycmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
show_history(line_input_state);
return EXIT_SUCCESS;
}
#endif
/*
* The export and readonly commands.
*/
static int FAST_FUNC
exportcmd(int argc UNUSED_PARAM, char **argv)
{
struct var *vp;
char *name;
const char *p;
char **aptr;
char opt;
int flag;
int flag_off;
/* "readonly" in bash accepts, but ignores -n.
* We do the same: it saves a conditional in nextopt's param.
*/
flag_off = 0;
while ((opt = nextopt("np")) != '\0') {
if (opt == 'n')
flag_off = VEXPORT;
}
flag = VEXPORT;
if (argv[0][0] == 'r') {
flag = VREADONLY;
flag_off = 0; /* readonly ignores -n */
}
flag_off = ~flag_off;
/*if (opt_p_not_specified) - bash doesnt check this. Try "export -p NAME" */
{
aptr = argptr;
name = *aptr;
if (name) {
do {
p = strchr(name, '=');
if (p != NULL) {
p++;
} else {
vp = *findvar(hashvar(name), name);
if (vp) {
vp->flags = ((vp->flags | flag) & flag_off);
continue;
}
}
setvar(name, p, (flag & flag_off));
} while ((name = *++aptr) != NULL);
return 0;
}
}
/* No arguments. Show the list of exported or readonly vars.
* -n is ignored.
*/
showvars(argv[0], flag, 0);
return 0;
}
/*
* Delete a function if it exists.
*/
static void
unsetfunc(const char *name)
{
struct tblentry *cmdp;
cmdp = cmdlookup(name, 0);
if (cmdp != NULL && cmdp->cmdtype == CMDFUNCTION)
delete_cmd_entry();
}
/*
* The unset builtin command. We unset the function before we unset the
* variable to allow a function to be unset when there is a readonly variable
* with the same name.
*/
static int FAST_FUNC
unsetcmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
char **ap;
int i;
int flag = 0;
int ret = 0;
while ((i = nextopt("vf")) != 0) {
flag = i;
}
for (ap = argptr; *ap; ap++) {
if (flag != 'f') {
i = unsetvar(*ap);
ret |= i;
if (!(i & 2))
continue;
}
if (flag != 'v')
unsetfunc(*ap);
}
return ret & 1;
}
static const unsigned char timescmd_str[] ALIGN1 = {
' ', offsetof(struct tms, tms_utime),
'\n', offsetof(struct tms, tms_stime),
' ', offsetof(struct tms, tms_cutime),
'\n', offsetof(struct tms, tms_cstime),
0
};
static int FAST_FUNC
timescmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
unsigned long clk_tck, s, t;
const unsigned char *p;
struct tms buf;
clk_tck = bb_clk_tck();
times(&buf);
p = timescmd_str;
do {
t = *(clock_t *)(((char *) &buf) + p[1]);
s = t / clk_tck;
t = t % clk_tck;
out1fmt("%lum%lu.%03lus%c",
s / 60, s % 60,
(t * 1000) / clk_tck,
p[0]);
p += 2;
} while (*p);
return 0;
}
#if ENABLE_FEATURE_SH_MATH
/*
* The let builtin. Partially stolen from GNU Bash, the Bourne Again SHell.
* Copyright (C) 1987, 1989, 1991 Free Software Foundation, Inc.
*
* Copyright (C) 2003 Vladimir Oleynik <dzo@simtreas.ru>
*/
static int FAST_FUNC
letcmd(int argc UNUSED_PARAM, char **argv)
{
arith_t i;
argv++;
if (!*argv)
ash_msg_and_raise_error("expression expected");
do {
i = ash_arith(*argv);
} while (*++argv);
return !i;
}
#endif
/*
* The read builtin. Options:
* -r Do not interpret '\' specially
* -s Turn off echo (tty only)
* -n NCHARS Read NCHARS max
* -p PROMPT Display PROMPT on stderr (if input is from tty)
* -t SECONDS Timeout after SECONDS (tty or pipe only)
* -u FD Read from given FD instead of fd 0
* This uses unbuffered input, which may be avoidable in some cases.
* TODO: bash also has:
* -a ARRAY Read into array[0],[1],etc
* -d DELIM End on DELIM char, not newline
* -e Use line editing (tty only)
*/
static int FAST_FUNC
readcmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
char *opt_n = NULL;
char *opt_p = NULL;
char *opt_t = NULL;
char *opt_u = NULL;
int read_flags = 0;
const char *r;
int i;
while ((i = nextopt("p:u:rt:n:s")) != '\0') {
switch (i) {
case 'p':
opt_p = optionarg;
break;
case 'n':
opt_n = optionarg;
break;
case 's':
read_flags |= BUILTIN_READ_SILENT;
break;
case 't':
opt_t = optionarg;
break;
case 'r':
read_flags |= BUILTIN_READ_RAW;
break;
case 'u':
opt_u = optionarg;
break;
default:
break;
}
}
/* "read -s" needs to save/restore termios, can't allow ^C
* to jump out of it.
*/
INT_OFF;
r = shell_builtin_read(setvar0,
argptr,
bltinlookup("IFS"), /* can be NULL */
read_flags,
opt_n,
opt_p,
opt_t,
opt_u
);
INT_ON;
if ((uintptr_t)r > 1)
ash_msg_and_raise_error(r);
return (uintptr_t)r;
}
static int FAST_FUNC
umaskcmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
static const char permuser[3] ALIGN1 = "ogu";
mode_t mask;
int symbolic_mode = 0;
while (nextopt("S") != '\0') {
symbolic_mode = 1;
}
INT_OFF;
mask = umask(0);
umask(mask);
INT_ON;
if (*argptr == NULL) {
if (symbolic_mode) {
char buf[sizeof(",u=rwx,g=rwx,o=rwx")];
char *p = buf;
int i;
i = 2;
for (;;) {
*p++ = ',';
*p++ = permuser[i];
*p++ = '=';
/* mask is 0..0uuugggooo. i=2 selects uuu bits */
if (!(mask & 0400)) *p++ = 'r';
if (!(mask & 0200)) *p++ = 'w';
if (!(mask & 0100)) *p++ = 'x';
mask <<= 3;
if (--i < 0)
break;
}
*p = '\0';
puts(buf + 1);
} else {
out1fmt("%04o\n", mask);
}
} else {
char *modestr = *argptr;
/* numeric umasks are taken as-is */
/* symbolic umasks are inverted: "umask a=rx" calls umask(222) */
if (!isdigit(modestr[0]))
mask ^= 0777;
mask = bb_parse_mode(modestr, mask);
if ((unsigned)mask > 0777) {
ash_msg_and_raise_error("illegal mode: %s", modestr);
}
if (!isdigit(modestr[0]))
mask ^= 0777;
umask(mask);
}
return 0;
}
static int FAST_FUNC
ulimitcmd(int argc UNUSED_PARAM, char **argv)
{
return shell_builtin_ulimit(argv);
}
/* ============ main() and helpers */
/*
* Called to exit the shell.
*/
static void
exitshell(void)
{
struct jmploc loc;
char *p;
int status;
#if ENABLE_FEATURE_EDITING_SAVE_ON_EXIT
save_history(line_input_state);
#endif
status = exitstatus;
TRACE(("pid %d, exitshell(%d)\n", getpid(), status));
if (setjmp(loc.loc)) {
if (exception_type == EXEXIT)
status = exitstatus;
goto out;
}
exception_handler = &loc;
p = trap[0];
if (p) {
trap[0] = NULL;
evalskip = 0;
evalstring(p, 0);
/*free(p); - we'll exit soon */
}
out:
/* dash wraps setjobctl(0) in "if (setjmp(loc.loc) == 0) {...}".
* our setjobctl(0) does not panic if tcsetpgrp fails inside it.
*/
setjobctl(0);
flush_stdout_stderr();
_exit(status);
/* NOTREACHED */
}
static void
init(void)
{
/* we will never free this */
basepf.next_to_pgetc = basepf.buf = ckmalloc(IBUFSIZ);
sigmode[SIGCHLD - 1] = S_DFL;
setsignal(SIGCHLD);
/* bash re-enables SIGHUP which is SIG_IGNed on entry.
* Try: "trap '' HUP; bash; echo RET" and type "kill -HUP $$"
*/
signal(SIGHUP, SIG_DFL);
{
char **envp;
const char *p;
struct stat st1, st2;
initvar();
for (envp = environ; envp && *envp; envp++) {
p = endofname(*envp);
if (p != *envp && *p == '=') {
setvareq(*envp, VEXPORT|VTEXTFIXED);
}
}
setvareq((char*)defoptindvar, VTEXTFIXED);
setvar0("PPID", utoa(getppid()));
#if ENABLE_ASH_BASH_COMPAT
p = lookupvar("SHLVL");
setvar("SHLVL", utoa((p ? atoi(p) : 0) + 1), VEXPORT);
if (!lookupvar("HOSTNAME")) {
struct utsname uts;
uname(&uts);
setvar0("HOSTNAME", uts.nodename);
}
#endif
p = lookupvar("PWD");
if (p) {
if (p[0] != '/' || stat(p, &st1) || stat(".", &st2)
|| st1.st_dev != st2.st_dev || st1.st_ino != st2.st_ino
) {
p = NULL;
}
}
setpwd(p, 0);
}
}
//usage:#define ash_trivial_usage
//usage: "[-/+OPTIONS] [-/+o OPT]... [-c 'SCRIPT' [ARG0 [ARGS]] / FILE [ARGS]]"
//usage:#define ash_full_usage "\n\n"
//usage: "Unix shell interpreter"
/*
* Process the shell command line arguments.
*/
static void
procargs(char **argv)
{
int i;
const char *xminusc;
char **xargv;
xargv = argv;
arg0 = xargv[0];
/* if (xargv[0]) - mmm, this is always true! */
xargv++;
for (i = 0; i < NOPTS; i++)
optlist[i] = 2;
argptr = xargv;
if (options(/*cmdline:*/ 1)) {
/* it already printed err message */
raise_exception(EXERROR);
}
xargv = argptr;
xminusc = minusc;
if (*xargv == NULL) {
if (xminusc)
ash_msg_and_raise_error(bb_msg_requires_arg, "-c");
sflag = 1;
}
if (iflag == 2 && sflag == 1 && isatty(0) && isatty(1))
iflag = 1;
if (mflag == 2)
mflag = iflag;
for (i = 0; i < NOPTS; i++)
if (optlist[i] == 2)
optlist[i] = 0;
#if DEBUG == 2
debug = 1;
#endif
/* POSIX 1003.2: first arg after -c cmd is $0, remainder $1... */
if (xminusc) {
minusc = *xargv++;
if (*xargv)
goto setarg0;
} else if (!sflag) {
setinputfile(*xargv, 0);
setarg0:
arg0 = *xargv++;
commandname = arg0;
}
shellparam.p = xargv;
#if ENABLE_ASH_GETOPTS
shellparam.optind = 1;
shellparam.optoff = -1;
#endif
/* assert(shellparam.malloced == 0 && shellparam.nparam == 0); */
while (*xargv) {
shellparam.nparam++;
xargv++;
}
optschanged();
}
/*
* Read /etc/profile, ~/.profile, $ENV.
*/
static void
read_profile(const char *name)
{
name = expandstr(name);
if (setinputfile(name, INPUT_PUSH_FILE | INPUT_NOFILE_OK) < 0)
return;
cmdloop(0);
popfile();
}
/*
* This routine is called when an error or an interrupt occurs in an
* interactive shell and control is returned to the main command loop.
* (In dash, this function is auto-generated by build machinery).
*/
static void
reset(void)
{
/* from eval.c: */
evalskip = 0;
loopnest = 0;
/* from expand.c: */
ifsfree();
/* from input.c: */
g_parsefile->left_in_buffer = 0;
g_parsefile->left_in_line = 0; /* clear input buffer */
popallfiles();
/* from redir.c: */
while (redirlist)
popredir(/*drop:*/ 0, /*restore:*/ 0);
}
#if PROFILE
static short profile_buf[16384];
extern int etext();
#endif
/*
* Main routine. We initialize things, parse the arguments, execute
* profiles if we're a login shell, and then call cmdloop to execute
* commands. The setjmp call sets up the location to jump to when an
* exception occurs. When an exception occurs the variable "state"
* is used to figure out how far we had gotten.
*/
int ash_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int ash_main(int argc UNUSED_PARAM, char **argv)
{
volatile smallint state;
struct jmploc jmploc;
struct stackmark smark;
/* Initialize global data */
INIT_G_misc();
INIT_G_memstack();
INIT_G_var();
#if ENABLE_ASH_ALIAS
INIT_G_alias();
#endif
INIT_G_cmdtable();
#if PROFILE
monitor(4, etext, profile_buf, sizeof(profile_buf), 50);
#endif
#if ENABLE_FEATURE_EDITING
line_input_state = new_line_input_t(FOR_SHELL | WITH_PATH_LOOKUP);
#endif
state = 0;
if (setjmp(jmploc.loc)) {
smallint e;
smallint s;
reset();
e = exception_type;
s = state;
if (e == EXEXIT || s == 0 || iflag == 0 || shlvl) {
exitshell();
}
if (e == EXINT) {
newline_and_flush(stderr);
}
popstackmark(&smark);
FORCE_INT_ON; /* enable interrupts */
if (s == 1)
goto state1;
if (s == 2)
goto state2;
if (s == 3)
goto state3;
goto state4;
}
exception_handler = &jmploc;
rootpid = getpid();
init();
setstackmark(&smark);
procargs(argv);
#if DEBUG
TRACE(("Shell args: "));
trace_puts_args(argv);
#endif
if (argv[0] && argv[0][0] == '-')
isloginsh = 1;
if (isloginsh) {
const char *hp;
state = 1;
read_profile("/etc/profile");
state1:
state = 2;
hp = lookupvar("HOME");
if (hp)
read_profile("$HOME/.profile");
}
state2:
state = 3;
if (
#ifndef linux
getuid() == geteuid() && getgid() == getegid() &&
#endif
iflag
) {
const char *shinit = lookupvar("ENV");
if (shinit != NULL && *shinit != '\0')
read_profile(shinit);
}
popstackmark(&smark);
state3:
state = 4;
if (minusc) {
/* evalstring pushes parsefile stack.
* Ensure we don't falsely claim that 0 (stdin)
* is one of stacked source fds.
* Testcase: ash -c 'exec 1>&0' must not complain. */
// if (!sflag) g_parsefile->pf_fd = -1;
// ^^ not necessary since now we special-case fd 0
// in is_hidden_fd() to not be considered "hidden fd"
evalstring(minusc, 0);
}
if (sflag || minusc == NULL) {
#if MAX_HISTORY > 0 && ENABLE_FEATURE_EDITING_SAVEHISTORY
if (iflag) {
const char *hp = lookupvar("HISTFILE");
if (!hp) {
hp = lookupvar("HOME");
if (hp) {
hp = concat_path_file(hp, ".ash_history");
setvar0("HISTFILE", hp);
free((char*)hp);
hp = lookupvar("HISTFILE");
}
}
if (hp)
line_input_state->hist_file = hp;
# if ENABLE_FEATURE_SH_HISTFILESIZE
hp = lookupvar("HISTFILESIZE");
line_input_state->max_history = size_from_HISTFILESIZE(hp);
# endif
}
#endif
state4: /* XXX ??? - why isn't this before the "if" statement */
cmdloop(1);
}
#if PROFILE
monitor(0);
#endif
#ifdef GPROF
{
extern void _mcleanup(void);
_mcleanup();
}
#endif
TRACE(("End of main reached\n"));
exitshell();
/* NOTREACHED */
}
/*-
* Copyright (c) 1989, 1991, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Kenneth Almquist.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
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