From cd2663f15e74274619dd97dc382bb858ac255872 Mon Sep 17 00:00:00 2001 From: Denis Vlasenko Date: Sun, 1 Jun 2008 22:36:39 +0000 Subject: [PATCH] ash: optional printf builtin. +25 bytes if off, +35 if on. by Cristian Ionescu-Idbohrn. --- coreutils/Kbuild | 1 + coreutils/chown.c | 1 - coreutils/printf.c | 18 +++++++++++++++--- include/applets.h | 2 +- include/libbb.h | 9 ++++++--- miscutils/last.c | 3 +++ miscutils/last_fancy.c | 3 +++ shell/Config.in | 7 +++++++ shell/ash.c | 14 +++++++++----- 9 files changed, 45 insertions(+), 13 deletions(-) diff --git a/coreutils/Kbuild b/coreutils/Kbuild index cb4543912..a5a2d4c26 100644 --- a/coreutils/Kbuild +++ b/coreutils/Kbuild @@ -54,6 +54,7 @@ lib-$(CONFIG_NOHUP) += nohup.o lib-$(CONFIG_OD) += od.o lib-$(CONFIG_PRINTENV) += printenv.o lib-$(CONFIG_PRINTF) += printf.o +lib-$(CONFIG_ASH_BUILTIN_PRINTF) += printf.o lib-$(CONFIG_PWD) += pwd.o lib-$(CONFIG_READLINK) += readlink.o lib-$(CONFIG_REALPATH) += realpath.o diff --git a/coreutils/chown.c b/coreutils/chown.c index eaaefaf29..78377e6a0 100644 --- a/coreutils/chown.c +++ b/coreutils/chown.c @@ -61,7 +61,6 @@ static int fileAction(const char *fileName, struct stat *statbuf, return FALSE; } -int chown_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; int chown_main(int argc ATTRIBUTE_UNUSED, char **argv) { int retval = EXIT_SUCCESS; diff --git a/coreutils/printf.c b/coreutils/printf.c index ebe961564..b7752369c 100644 --- a/coreutils/printf.c +++ b/coreutils/printf.c @@ -193,6 +193,7 @@ static char **print_formatted(char *f, char **argv) unsigned direc_length; /* Length of % directive. */ int field_width; /* Arg to first '*', or -1 if none. */ int precision; /* Arg to second '*', or -1 if none. */ + char **saved_argv = argv; for (; *f; ++f) { switch (*f) { @@ -264,8 +265,9 @@ static char **print_formatted(char *f, char **argv) precision, ""); break; case '\\': - if (*++f == 'c') - exit(EXIT_SUCCESS); + if (*++f == 'c') { + return saved_argv; /* causes main() to exit */ + } bb_putchar(bb_process_escape_sequence((const char **)&f)); f--; break; @@ -277,12 +279,22 @@ static char **print_formatted(char *f, char **argv) return argv; } -int printf_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; int printf_main(int argc ATTRIBUTE_UNUSED, char **argv) { char *format; char **argv2; + /* We must check that stdout is not closed. + * The reason for this is highly non-obvious. printf_main is used from shell. + * Shell must correctly handle 'printf "%s" foo' + * if stdout is closed. With stdio, output gets shoveled into + * stdout buffer, and even fflush cannot clear it out. It seems that + * even if libc receives EBADF on write attempts, it feels determined + * to output data no matter what. So it will try later, + * and possibly will clobber future output. Not good. */ + if (dup2(1, 1) != 1) + return -1; + /* bash builtin errors out on "printf '-%s-\n' foo", * coreutils-6.9 works. Both work with "printf -- '-%s-\n' foo". * We will mimic coreutils. */ diff --git a/include/applets.h b/include/applets.h index 17113dfe7..e7fc3c03c 100644 --- a/include/applets.h +++ b/include/applets.h @@ -275,7 +275,7 @@ USE_PIVOT_ROOT(APPLET(pivot_root, _BB_DIR_SBIN, _BB_SUID_NEVER)) USE_PKILL(APPLET_ODDNAME(pkill, pgrep, _BB_DIR_USR_BIN, _BB_SUID_NEVER, pkill)) USE_HALT(APPLET_ODDNAME(poweroff, halt, _BB_DIR_SBIN, _BB_SUID_NEVER, poweroff)) USE_PRINTENV(APPLET(printenv, _BB_DIR_BIN, _BB_SUID_NEVER)) -USE_PRINTF(APPLET(printf, _BB_DIR_USR_BIN, _BB_SUID_NEVER)) +USE_PRINTF(APPLET_NOFORK(printf, printf, _BB_DIR_USR_BIN, _BB_SUID_NEVER, printf)) USE_PS(APPLET(ps, _BB_DIR_BIN, _BB_SUID_NEVER)) USE_PSCAN(APPLET(pscan, _BB_DIR_USR_BIN, _BB_SUID_NEVER)) USE_PWD(APPLET_NOFORK(pwd, pwd, _BB_DIR_BIN, _BB_SUID_NEVER, pwd)) diff --git a/include/libbb.h b/include/libbb.h index 947f28d79..c79cd8b20 100644 --- a/include/libbb.h +++ b/include/libbb.h @@ -878,13 +878,16 @@ extern void bb_verror_msg(const char *s, va_list p, const char *strerr); #endif -/* applets which are useful from another applets */ +/* Applets which are useful from another applets */ int bb_cat(char** argv); -/* If shell needs them, these three "exist" even if not enabled as applets */ +/* If shell needs them, they exist even if not enabled as applets */ int echo_main(int argc, char** argv) USE_ECHO(MAIN_EXTERNALLY_VISIBLE); +int printf_main(int argc, char **argv) USE_PRINTF(MAIN_EXTERNALLY_VISIBLE); int test_main(int argc, char **argv) USE_TEST(MAIN_EXTERNALLY_VISIBLE); int kill_main(int argc, char **argv) USE_KILL(MAIN_EXTERNALLY_VISIBLE); -int chown_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; +/* Similar, but used by chgrp, not shell */ +int chown_main(int argc, char **argv) USE_CHOWN(MAIN_EXTERNALLY_VISIBLE); +/* Don't need USE_xxx() guard for these */ int gunzip_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; int bunzip2_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; int bbunpack(char **argv, diff --git a/miscutils/last.c b/miscutils/last.c index a8800bfe6..612f50488 100644 --- a/miscutils/last.c +++ b/miscutils/last.c @@ -10,6 +10,9 @@ #include "libbb.h" #include +/* NB: ut_name and ut_user are the same field, use only one name (ut_user) + * to reduce confusion */ + #ifndef SHUTDOWN_TIME # define SHUTDOWN_TIME 254 #endif diff --git a/miscutils/last_fancy.c b/miscutils/last_fancy.c index 0dba9dca7..2b7fee6e5 100644 --- a/miscutils/last_fancy.c +++ b/miscutils/last_fancy.c @@ -10,6 +10,9 @@ #include "libbb.h" #include +/* NB: ut_name and ut_user are the same field, use only one name (ut_user) + * to reduce confusion */ + #ifndef SHUTDOWN_TIME # define SHUTDOWN_TIME 254 #endif diff --git a/shell/Config.in b/shell/Config.in index 94ffa09f8..a6701622c 100644 --- a/shell/Config.in +++ b/shell/Config.in @@ -114,6 +114,13 @@ config ASH_BUILTIN_ECHO help Enable support for echo, builtin to ash. +config ASH_BUILTIN_PRINTF + bool "Builtin version of 'printf'" + default y + depends on ASH + help + Enable support for printf, builtin to ash. + config ASH_BUILTIN_TEST bool "Builtin version of 'test'" default y diff --git a/shell/ash.c b/shell/ash.c index 20b93f326..31beb8671 100644 --- a/shell/ash.c +++ b/shell/ash.c @@ -8488,17 +8488,18 @@ static int ulimitcmd(int, char **); * Apart from the above, [[ expr ]] should work as [ expr ] */ -#define testcmd test_main -#define echocmd echo_main +#define echocmd echo_main +#define printfcmd printf_main +#define testcmd test_main /* 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 }, + { BUILTIN_REGULAR "[", testcmd }, #if ENABLE_ASH_BASH_COMPAT - { BUILTIN_REGULAR "[[", testcmd }, + { BUILTIN_REGULAR "[[", testcmd }, #endif #endif #if ENABLE_ASH_ALIAS @@ -8540,6 +8541,9 @@ static const struct builtincmd builtintab[] = { { 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 }, @@ -8548,7 +8552,7 @@ static const struct builtincmd builtintab[] = { { BUILTIN_SPEC_REG "shift", shiftcmd }, { BUILTIN_SPEC_REG "source", dotcmd }, #if ENABLE_ASH_BUILTIN_TEST - { BUILTIN_REGULAR "test", testcmd }, + { BUILTIN_REGULAR "test", testcmd }, #endif { BUILTIN_SPEC_REG "times", timescmd }, { BUILTIN_SPEC_REG "trap", trapcmd },