busybox/coreutils/touch.c
Denys Vlasenko 92ffe0571a date,touch: treat 2-digit years better (fit them into +-50 yrs around today)
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2011-01-02 20:02:09 +01:00

158 lines
4.4 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Mini touch implementation for busybox
*
* Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
/* BB_AUDIT SUSv3 _NOT_ compliant -- options -a, -m, -r, -t not supported. */
/* http://www.opengroup.org/onlinepubs/007904975/utilities/touch.html */
/* Mar 16, 2003 Manuel Novoa III (mjn3@codepoet.org)
*
* Previous version called open() and then utime(). While this will be
* be necessary to implement -r and -t, it currently only makes things bigger.
* Also, exiting on a failure was a bug. All args should be processed.
*/
#include "libbb.h"
//config:config TOUCH
//config: bool "touch"
//config: default y
//config: help
//config: touch is used to create or change the access and/or
//config: modification timestamp of specified files.
//applet:IF_TOUCH(APPLET_NOFORK(touch, touch, _BB_DIR_BIN, _BB_SUID_DROP, touch))
//kbuild:lib-$(CONFIG_TOUCH) += touch.o
//usage:#define touch_trivial_usage
//usage: "[-c]" IF_DESKTOP(" [-d DATE] [-r FILE]") " FILE [FILE]..."
//usage:#define touch_full_usage "\n\n"
//usage: "Update the last-modified date on the given FILE[s]\n"
//usage: "\nOptions:"
//usage: "\n -c Don't create files"
//usage: IF_DESKTOP(
//usage: "\n -d DT Date/time to use"
//usage: "\n -r FILE Use FILE's date/time"
//usage: )
//usage:
//usage:#define touch_example_usage
//usage: "$ ls -l /tmp/foo\n"
//usage: "/bin/ls: /tmp/foo: No such file or directory\n"
//usage: "$ touch /tmp/foo\n"
//usage: "$ ls -l /tmp/foo\n"
//usage: "-rw-rw-r-- 1 andersen andersen 0 Apr 15 01:11 /tmp/foo\n"
/* This is a NOFORK applet. Be very careful! */
/* coreutils implements:
* -a change only the access time
* -c, --no-create
* do not create any files
* -d, --date=STRING
* parse STRING and use it instead of current time
* -f (ignored, BSD compat)
* -m change only the modification time
* -r, --reference=FILE
* use this file's times instead of current time
* -t STAMP
* use [[CC]YY]MMDDhhmm[.ss] instead of current time
* --time=WORD
* change the specified time: WORD is access, atime, or use
*/
int touch_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int touch_main(int argc UNUSED_PARAM, char **argv)
{
int fd;
int status = EXIT_SUCCESS;
int opts;
#if ENABLE_DESKTOP
# if ENABLE_LONG_OPTS
static const char touch_longopts[] ALIGN1 =
/* name, has_arg, val */
"no-create\0" No_argument "c"
"reference\0" Required_argument "r"
"date\0" Required_argument "d"
;
# endif
char *reference_file = NULL;
char *date_str = NULL;
struct timeval timebuf[2];
timebuf[1].tv_usec = timebuf[0].tv_usec = 0;
#else
# define reference_file NULL
# define date_str NULL
# define timebuf ((struct timeval*)NULL)
#endif
#if ENABLE_DESKTOP && ENABLE_LONG_OPTS
applet_long_options = touch_longopts;
#endif
/* -d and -t both set time. In coreutils,
* accepted data format differs a bit between -d and -t.
* We accept the same formats for both */
opts = getopt32(argv, "c" IF_DESKTOP("r:d:t:")
/*ignored:*/ "fma"
IF_DESKTOP(, &reference_file)
IF_DESKTOP(, &date_str)
IF_DESKTOP(, &date_str)
);
opts &= 1; /* only -c bit is left */
argv += optind;
if (!*argv) {
bb_show_usage();
}
if (reference_file) {
struct stat stbuf;
xstat(reference_file, &stbuf);
timebuf[1].tv_sec = timebuf[0].tv_sec = stbuf.st_mtime;
}
if (date_str) {
struct tm tm_time;
time_t t;
//memset(&tm_time, 0, sizeof(tm_time));
/* Better than memset: makes "HH:MM" dates meaningful */
time(&t);
localtime_r(&t, &tm_time);
parse_datestr(date_str, &tm_time);
/* Correct any day of week and day of year etc. fields */
tm_time.tm_isdst = -1; /* Be sure to recheck dst */
t = validate_tm_time(date_str, &tm_time);
timebuf[1].tv_sec = timebuf[0].tv_sec = t;
}
do {
if (utimes(*argv, (reference_file || date_str) ? timebuf : NULL) != 0) {
if (errno == ENOENT) { /* no such file */
if (opts) { /* creation is disabled, so ignore */
continue;
}
/* Try to create the file */
fd = open(*argv, O_RDWR | O_CREAT, 0666);
if (fd >= 0) {
xclose(fd);
if (reference_file || date_str)
utimes(*argv, timebuf);
continue;
}
}
status = EXIT_FAILURE;
bb_simple_perror_msg(*argv);
}
} while (*++argv);
return status;
}