hush/ls.c
Eric Andersen c674d70699 Comment on kernel stuff
-Erik
2000-07-10 22:57:14 +00:00

620 lines
14 KiB
C

/* vi: set sw=4 ts=4: */
/*
* tiny-ls.c version 0.1.0: A minimalist 'ls'
* Copyright (C) 1996 Brian Candler <B.Candler@pobox.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/*
* To achieve a small memory footprint, this version of 'ls' doesn't do any
* file sorting, and only has the most essential command line switches
* (i.e. the ones I couldn't live without :-) All features which involve
* linking in substantial chunks of libc can be disabled.
*
* Although I don't really want to add new features to this program to
* keep it small, I *am* interested to receive bug fixes and ways to make
* it more portable.
*
* KNOWN BUGS:
* 1. ls -l of a directory doesn't give "total <blocks>" header
* 2. ls of a symlink to a directory doesn't list directory contents
* 3. hidden files can make column width too large
*
* NON-OPTIMAL BEHAVIOUR:
* 1. autowidth reads directories twice
* 2. if you do a short directory listing without filetype characters
* appended, there's no need to stat each one
* PORTABILITY:
* 1. requires lstat (BSD) - how do you do it without?
*/
#define TERMINAL_WIDTH 80 /* use 79 if your terminal has linefold bug */
#define COLUMN_WIDTH 14 /* default if AUTOWIDTH not defined */
#define COLUMN_GAP 2 /* includes the file type char, if present */
#define HAS_REWINDDIR
/************************************************************************/
#include "internal.h"
# include <sys/types.h>
#include <sys/stat.h>
#include <stdio.h>
#include <unistd.h>
#include <dirent.h>
#include <errno.h>
#include <stdio.h>
#ifdef BB_FEATURE_LS_TIMESTAMPS
#include <time.h>
#endif
#define TYPEINDEX(mode) (((mode) >> 12) & 0x0f)
#define TYPECHAR(mode) ("0pcCd?bB-?l?s???" [TYPEINDEX(mode)])
#ifdef BB_FEATURE_LS_FILETYPES
#define APPCHAR(mode) ("\0|\0\0/\0\0\0\0\0@\0=\0\0\0" [TYPEINDEX(mode)])
#endif
#define FMT_AUTO 0
#define FMT_LONG 1 /* one record per line, extended info */
#define FMT_SINGLE 2 /* one record per line */
#define FMT_ROWS 3 /* print across rows */
#define FMT_COLUMNS 3 /* fill columns (same, since we don't sort) */
#define TIME_MOD 0
#define TIME_CHANGE 1
#define TIME_ACCESS 2
#define DISP_FTYPE 1 /* show character for file type */
#define DISP_EXEC 2 /* show '*' if regular executable file */
#define DISP_HIDDEN 4 /* show files starting . (except . and ..) */
#define DISP_DOT 8 /* show . and .. */
#define DISP_NUMERIC 16 /* numeric uid and gid */
#define DISP_FULLTIME 32 /* show extended time display */
#define DIR_NOLIST 64 /* show directory as itself, not contents */
#define DISP_DIRNAME 128 /* show directory name (for internal use) */
#define DISP_RECURSIVE 256 /* Do a recursive listing */
#ifndef MAJOR
#define MAJOR(dev) (((dev)>>8)&0xff)
#define MINOR(dev) ((dev)&0xff)
#endif
static unsigned char display_fmt = FMT_AUTO;
static unsigned short opts = 0;
static unsigned short column = 0;
#ifdef BB_FEATURE_AUTOWIDTH
static unsigned short terminal_width = 0;
static unsigned short column_width = 0;
static unsigned short toplevel_column_width = 0;
#else
#define terminal_width TERMINAL_WIDTH
#define column_width COLUMN_WIDTH
#endif
#ifdef BB_FEATURE_LS_TIMESTAMPS
static unsigned char time_fmt = TIME_MOD;
#endif
#define wr(data,len) fwrite(data, 1, len, stdout)
static void writenum(long val, short minwidth)
{
char scratch[128];
char *p = scratch + sizeof(scratch);
short len = 0;
short neg = (val < 0);
if (neg)
val = -val;
do
*--p = (val % 10) + '0', len++, val /= 10;
while (val);
if (neg)
*--p = '-', len++;
while (len < minwidth)
*--p = ' ', len++;
wr(p, len);
column += len;
}
static void newline(void)
{
if (column > 0) {
wr("\n", 1);
column = 0;
}
}
static void tab(short col)
{
static const char spaces[] = " ";
#define nspaces ((sizeof spaces)-1) /* null terminator! */
short n = col - column;
if (n > 0) {
column = col;
while (n > nspaces) {
wr(spaces, nspaces);
n -= nspaces;
}
/* must be 1...(sizeof spaces) left */
wr(spaces, n);
}
#undef nspaces
}
#ifdef BB_FEATURE_LS_FILETYPES
static char append_char(mode_t mode)
{
if (!(opts & DISP_FTYPE))
return '\0';
if ((opts & DISP_EXEC) && S_ISREG(mode)
&& (mode & (S_IXUSR | S_IXGRP | S_IXOTH))) return '*';
return APPCHAR(mode);
}
#endif
/**
**
** Display a file or directory as a single item
** (in either long or short format)
**
**/
static void list_single(const char *name, struct stat *info,
const char *fullname)
{
char scratch[BUFSIZ + 1];
short len = strlen(name);
#ifdef BB_FEATURE_LS_FILETYPES
char append = append_char(info->st_mode);
#endif
if (display_fmt == FMT_LONG) {
mode_t mode = info->st_mode;
newline();
wr(modeString(mode), 10);
column = 10;
writenum((long) info->st_nlink, (short) 5);
fputs(" ", stdout);
#ifdef BB_FEATURE_LS_USERNAME
if (!(opts & DISP_NUMERIC)) {
memset(scratch, 0, sizeof(scratch));
my_getpwuid(scratch, info->st_uid);
if (*scratch) {
fputs(scratch, stdout);
if (strlen(scratch) <= 8)
wr(" ", 9 - strlen(scratch));
} else {
writenum((long) info->st_uid, (short) 8);
fputs(" ", stdout);
}
} else
#endif
{
writenum((long) info->st_uid, (short) 8);
fputs(" ", stdout);
}
#ifdef BB_FEATURE_LS_USERNAME
if (!(opts & DISP_NUMERIC)) {
memset(scratch, 0, sizeof(scratch));
my_getgrgid(scratch, info->st_gid);
if (*scratch) {
fputs(scratch, stdout);
if (strlen(scratch) <= 8)
wr(" ", 8 - strlen(scratch));
} else
writenum((long) info->st_gid, (short) 8);
} else
#endif
writenum((long) info->st_gid, (short) 8);
//tab(26);
if (S_ISBLK(mode) || S_ISCHR(mode)) {
writenum((long) MAJOR(info->st_rdev), (short) 3);
fputs(", ", stdout);
writenum((long) MINOR(info->st_rdev), (short) 3);
} else
writenum((long) info->st_size, (short) 8);
fputs(" ", stdout);
//tab(32);
#ifdef BB_FEATURE_LS_TIMESTAMPS
{
time_t cal;
char *string;
switch (time_fmt) {
case TIME_CHANGE:
cal = info->st_ctime;
break;
case TIME_ACCESS:
cal = info->st_atime;
break;
default:
cal = info->st_mtime;
break;
}
string = ctime(&cal);
if (opts & DISP_FULLTIME)
wr(string, 24);
else {
time_t age = time(NULL) - cal;
wr(string + 4, 7); /* mmm_dd_ */
if (age < 3600L * 24 * 365 / 2 && age > -15 * 60)
/* hh:mm if less than 6 months old */
wr(string + 11, 5);
else
/* _yyyy otherwise */
wr(string + 19, 5);
}
wr(" ", 1);
}
#else
fputs("--- -- ----- ", stdout);
#endif
wr(name, len);
if (S_ISLNK(mode)) {
wr(" -> ", 4);
len = readlink(fullname, scratch, sizeof scratch);
if (len > 0)
fwrite(scratch, 1, len, stdout);
#ifdef BB_FEATURE_LS_FILETYPES
/* show type of destination */
if (opts & DISP_FTYPE) {
if (!stat(fullname, info)) {
append = append_char(info->st_mode);
if (append)
fputc(append, stdout);
}
}
#endif
}
#ifdef BB_FEATURE_LS_FILETYPES
else if (append)
wr(&append, 1);
#endif
} else {
static short nexttab = 0;
/* sort out column alignment */
if (column == 0); /* nothing to do */
else if (display_fmt == FMT_SINGLE)
newline();
else {
if (nexttab + column_width > terminal_width
#ifndef BB_FEATURE_AUTOWIDTH
|| nexttab + len >= terminal_width
#endif
)
newline();
else
tab(nexttab);
}
/* work out where next column starts */
#ifdef BB_FEATURE_AUTOWIDTH
/* we know the calculated width is big enough */
nexttab = column + column_width + COLUMN_GAP;
#else
/* might cover more than one fixed-width column */
nexttab = column;
do
nexttab += column_width + COLUMN_GAP;
while (nexttab < (column + len + COLUMN_GAP));
#endif
/* now write the data */
wr(name, len);
column = column + len;
#ifdef BB_FEATURE_LS_FILETYPES
if (append)
wr(&append, 1), column++;
#endif
}
}
/**
**
** List the given file or directory, expanding a directory
** to show its contents if required
**
**/
static int list_item(const char *name)
{
struct stat info;
DIR *dir;
struct dirent *entry;
char fullname[BUFSIZ + 1], *fnend;
if (lstat(name, &info))
goto listerr;
if (!S_ISDIR(info.st_mode) || (opts & DIR_NOLIST)) {
#ifdef BB_FEATURE_AUTOWIDTH
column_width = toplevel_column_width;
#endif
list_single(name, &info, name);
return 0;
}
/* Otherwise, it's a directory we want to list the contents of */
if (opts & DISP_DIRNAME) { /* identify the directory */
if (column)
wr("\n\n", 2), column = 0;
wr(name, strlen(name));
wr(":\n", 2);
}
dir = opendir(name);
if (!dir)
goto listerr;
#ifdef BB_FEATURE_AUTOWIDTH
column_width = 0;
while ((entry = readdir(dir)) != NULL) {
short w = strlen(entry->d_name);
if (column_width < w)
column_width = w;
}
#ifdef HAS_REWINDDIR
rewinddir(dir);
#else
closedir(dir);
dir = opendir(name);
if (!dir)
goto listerr;
#endif
#endif
/* List the contents */
strcpy(fullname, name); /* *** ignore '.' by itself */
fnend = fullname + strlen(fullname);
if (fnend[-1] != '/')
*fnend++ = '/';
while ((entry = readdir(dir)) != NULL) {
const char *en = entry->d_name;
if (en[0] == '.') {
if (!en[1] || (en[1] == '.' && !en[2])) { /* . or .. */
if (!(opts & DISP_DOT))
continue;
} else if (!(opts & DISP_HIDDEN))
continue;
}
/* FIXME: avoid stat if not required */
strcpy(fnend, entry->d_name);
if (lstat(fullname, &info))
goto direrr; /* (shouldn't fail) */
list_single(entry->d_name, &info, fullname);
}
closedir(dir);
if (opts & DISP_DIRNAME) { /* separate the directory */
if (column) {
wr("\n", 1);
}
wr("\n", 1);
column = 0;
}
return 0;
direrr:
closedir(dir);
listerr:
newline();
perror(name);
return 1;
}
static const char ls_usage[] = "ls [-1a"
#ifdef BB_FEATURE_LS_TIMESTAMPS
"c"
#endif
"d"
#ifdef BB_FEATURE_LS_TIMESTAMPS
"e"
#endif
"ln"
#ifdef BB_FEATURE_LS_FILETYPES
"p"
#endif
#ifdef BB_FEATURE_LS_TIMESTAMPS
"u"
#endif
"xAC"
#ifdef BB_FEATURE_LS_FILETYPES
"F"
#endif
#ifdef BB_FEATURE_LS_RECURSIVE
"R"
#endif
"] [filenames...]\n"
#ifndef BB_FEATURE_TRIVIAL_HELP
"\nList directory contents\n\n"
"Options:\n"
"\t-a\tdo not hide entries starting with .\n"
#ifdef BB_FEATURE_LS_TIMESTAMPS
"\t-c\twith -l: show ctime (the time of last\n"
"\t\tmodification of file status information)\n"
#endif
"\t-d\tlist directory entries instead of contents\n"
#ifdef BB_FEATURE_LS_TIMESTAMPS
"\t-e\tlist both full date and full time\n"
#endif
"\t-l\tuse a long listing format\n"
"\t-n\tlist numeric UIDs and GIDs instead of names\n"
#ifdef BB_FEATURE_LS_FILETYPES
"\t-p\tappend indicator (one of /=@|) to entries\n"
#endif
#ifdef BB_FEATURE_LS_TIMESTAMPS
"\t-u\twith -l: show access time (the time of last\n"
"\t\taccess of the file)\n"
#endif
"\t-x\tlist entries by lines instead of by columns\n"
"\t-A\tdo not list implied . and ..\n"
"\t-C\tlist entries by columns\n"
#ifdef BB_FEATURE_LS_FILETYPES
"\t-F\tappend indicator (one of */=@|) to entries\n"
#endif
#ifdef BB_FEATURE_LS_RECURSIVE
"\t-R\tlist subdirectories recursively\n"
#endif
#endif
;
#ifdef BB_FEATURE_LS_RECURSIVE
static int dirAction(const char *fileName, struct stat *statbuf, void* junk)
{
int i;
fprintf(stdout, "\n%s:\n", fileName);
i = list_item(fileName);
newline();
return (i);
}
#endif
extern int ls_main(int argc, char **argv)
{
int argi = 1, i;
/* process options */
while (argi < argc && argv[argi][0] == '-') {
const char *p = &argv[argi][1];
if (!*p)
goto print_usage_message; /* "-" by itself not allowed */
if (*p == '-') {
if (!p[1]) { /* "--" forces end of options */
argi++;
break;
}
/* it's a long option name - we don't support them */
goto print_usage_message;
}
while (*p)
switch (*p++) {
case 'l':
display_fmt = FMT_LONG;
break;
case '1':
display_fmt = FMT_SINGLE;
break;
case 'x':
display_fmt = FMT_ROWS;
break;
case 'C':
display_fmt = FMT_COLUMNS;
break;
#ifdef BB_FEATURE_LS_FILETYPES
case 'p':
opts |= DISP_FTYPE;
break;
case 'F':
opts |= DISP_FTYPE | DISP_EXEC;
break;
#endif
case 'A':
opts |= DISP_HIDDEN;
break;
case 'a':
opts |= DISP_HIDDEN | DISP_DOT;
break;
case 'n':
opts |= DISP_NUMERIC;
break;
case 'd':
opts |= DIR_NOLIST;
break;
#ifdef BB_FEATURE_LS_TIMESTAMPS
case 'u':
time_fmt = TIME_ACCESS;
break;
case 'c':
time_fmt = TIME_CHANGE;
break;
case 'e':
opts |= DISP_FULLTIME;
break;
#endif
#ifdef BB_FEATURE_LS_RECURSIVE
case 'R':
opts |= DISP_RECURSIVE;
break;
#endif
case 'g': /* ignore -- for ftp servers */
break;
default:
goto print_usage_message;
}
argi++;
}
/* choose a display format */
if (display_fmt == FMT_AUTO)
display_fmt = isatty(fileno(stdout)) ? FMT_COLUMNS : FMT_SINGLE;
if (argi < argc - 1)
opts |= DISP_DIRNAME; /* 2 or more items? label directories */
#ifdef BB_FEATURE_AUTOWIDTH
/* could add a -w option and/or TIOCGWINSZ call */
if (terminal_width < 1)
terminal_width = TERMINAL_WIDTH;
for (i = argi; i < argc; i++) {
int len = strlen(argv[i]);
if (toplevel_column_width < len)
toplevel_column_width = len;
}
#endif
/* process files specified, or current directory if none */
#ifdef BB_FEATURE_LS_RECURSIVE
if (opts & DISP_RECURSIVE) {
i = 0;
if (argi == argc) {
i = recursiveAction(".", TRUE, FALSE, FALSE, NULL, dirAction, NULL);
}
while (argi < argc) {
i |= recursiveAction(argv[argi++], TRUE, FALSE, FALSE, NULL, dirAction, NULL);
}
} else
#endif
{
i = 0;
if (argi == argc)
i = list_item(".");
while (argi < argc)
i |= list_item(argv[argi++]);
newline();
}
exit(i);
print_usage_message:
usage(ls_usage);
exit(FALSE);
}