1 /* touch -- change modification and access times of files
2 Copyright (C) 1987-2012 Free Software Foundation, Inc.
4 This program is free software: you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation, either version 3 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program. If not, see <http://www.gnu.org/licenses/>. */
17 /* Written by Paul Rubin, Arnold Robbins, Jim Kingdon, David MacKenzie,
23 #include <sys/types.h>
29 #include "fd-reopen.h"
30 #include "parse-datetime.h"
34 #include "stat-time.h"
37 /* The official name of this program (e.g., no 'g' prefix). */
38 #define PROGRAM_NAME "touch"
41 proper_name ("Paul Rubin"), \
42 proper_name ("Arnold Robbins"), \
43 proper_name ("Jim Kingdon"), \
44 proper_name ("David MacKenzie"), \
45 proper_name ("Randy Smith")
47 /* Bitmasks for 'change_times'. */
51 /* Which timestamps to change. */
52 static int change_times
;
54 /* (-c) If true, don't create if not already there. */
55 static bool no_create
;
57 /* (-r) If true, use times from a reference file. */
60 /* (-h) If true, change the times of an existing symlink, if possible. */
61 static bool no_dereference
;
63 /* If true, the only thing we have to do is change both the
64 modification and access time to the current time, so we don't
65 have to own the file, just be able to read and write it.
66 On some systems, we can do this if we own the file, even though
67 we have neither read nor write access to it. */
68 static bool amtime_now
;
70 /* New access and modification times to use when setting time. */
71 static struct timespec newtime
[2];
73 /* File to use for -r. */
74 static char *ref_file
;
76 /* For long options that have no equivalent short option, use a
77 non-character as a pseudo short option, starting with CHAR_MAX + 1. */
80 TIME_OPTION
= CHAR_MAX
+ 1
83 static struct option
const longopts
[] =
85 {"time", required_argument
, NULL
, TIME_OPTION
},
86 {"no-create", no_argument
, NULL
, 'c'},
87 {"date", required_argument
, NULL
, 'd'},
88 {"reference", required_argument
, NULL
, 'r'},
89 {"no-dereference", no_argument
, NULL
, 'h'},
90 {GETOPT_HELP_OPTION_DECL
},
91 {GETOPT_VERSION_OPTION_DECL
},
95 /* Valid arguments to the '--time' option. */
96 static char const* const time_args
[] =
98 "atime", "access", "use", "mtime", "modify", NULL
101 /* The bits in 'change_times' that those arguments set. */
102 static int const time_masks
[] =
104 CH_ATIME
, CH_ATIME
, CH_ATIME
, CH_MTIME
, CH_MTIME
107 /* Store into *RESULT the result of interpreting FLEX_DATE as a date,
108 relative to NOW. If NOW is null, use the current time. */
111 get_reldate (struct timespec
*result
,
112 char const *flex_date
, struct timespec
const *now
)
114 if (! parse_datetime (result
, flex_date
, now
))
115 error (EXIT_FAILURE
, 0, _("invalid date format %s"), quote (flex_date
));
118 /* Update the time of file FILE according to the options given.
119 Return true if successful. */
122 touch (const char *file
)
127 struct timespec
const *t
= newtime
;
129 if (STREQ (file
, "-"))
131 else if (! (no_create
|| no_dereference
))
133 /* Try to open FILE, creating it if necessary. */
134 fd
= fd_reopen (STDIN_FILENO
, file
,
135 O_WRONLY
| O_CREAT
| O_NONBLOCK
| O_NOCTTY
, MODE_RW_UGO
);
137 /* Don't save a copy of errno if it's EISDIR, since that would lead
138 touch to give a bogus diagnostic for e.g., 'touch /' (assuming
139 we don't own / or have write access to it). On Solaris 5.6,
140 and probably other systems, it is EINVAL. On SunOS4, it's EPERM. */
141 if (fd
== -1 && errno
!= EISDIR
&& errno
!= EINVAL
&& errno
!= EPERM
)
145 if (change_times
!= (CH_ATIME
| CH_MTIME
))
147 /* We're setting only one of the time values. */
148 if (change_times
== CH_MTIME
)
149 newtime
[0].tv_nsec
= UTIME_OMIT
;
152 assert (change_times
== CH_ATIME
);
153 newtime
[1].tv_nsec
= UTIME_OMIT
;
159 /* Pass NULL to futimens so it will not fail if we have
160 write access to the file, but don't own it. */
164 ok
= (fdutimensat (fd
, AT_FDCWD
, (fd
== STDOUT_FILENO
? NULL
: file
), t
,
165 (no_dereference
&& fd
== -1) ? AT_SYMLINK_NOFOLLOW
: 0)
168 if (fd
== STDIN_FILENO
)
170 if (close (STDIN_FILENO
) != 0)
172 error (0, errno
, _("closing %s"), quote (file
));
176 else if (fd
== STDOUT_FILENO
)
178 /* Do not diagnose "touch -c - >&-". */
179 if (!ok
&& errno
== EBADF
&& no_create
)
187 /* The wording of this diagnostic should cover at least two cases:
188 - the file does not exist, but the parent directory is unwritable
189 - the file exists, but it isn't writable
190 I think it's not worth trying to distinguish them. */
191 error (0, open_errno
, _("cannot touch %s"), quote (file
));
195 if (no_create
&& errno
== ENOENT
)
197 error (0, errno
, _("setting times of %s"), quote (file
));
208 if (status
!= EXIT_SUCCESS
)
212 printf (_("Usage: %s [OPTION]... FILE...\n"), program_name
);
214 Update the access and modification times of each FILE to the current time.\n\
216 A FILE argument that does not exist is created empty, unless -c or -h\n\
219 A FILE argument string of - is handled specially and causes touch to\n\
220 change the times of the file associated with standard output.\n\
224 Mandatory arguments to long options are mandatory for short options too.\n\
227 -a change only the access time\n\
228 -c, --no-create do not create any files\n\
229 -d, --date=STRING parse STRING and use it instead of current time\n\
233 -h, --no-dereference affect each symbolic link instead of any referenced\n\
234 file (useful only on systems that can change the\n\
235 timestamps of a symlink)\n\
236 -m change only the modification time\n\
239 -r, --reference=FILE use this file's times instead of current time\n\
240 -t STAMP use [[CC]YY]MMDDhhmm[.ss] instead of current time\n\
241 --time=WORD change the specified time:\n\
242 WORD is access, atime, or use: equivalent to -a\n\
243 WORD is modify or mtime: equivalent to -m\n\
245 fputs (HELP_OPTION_DESCRIPTION
, stdout
);
246 fputs (VERSION_OPTION_DESCRIPTION
, stdout
);
249 Note that the -d and -t options accept different time-date formats.\n\
251 emit_ancillary_info ();
257 main (int argc
, char **argv
)
260 bool date_set
= false;
262 char const *flex_date
= NULL
;
264 initialize_main (&argc
, &argv
);
265 set_program_name (argv
[0]);
266 setlocale (LC_ALL
, "");
267 bindtextdomain (PACKAGE
, LOCALEDIR
);
268 textdomain (PACKAGE
);
270 atexit (close_stdout
);
273 no_create
= use_ref
= false;
275 while ((c
= getopt_long (argc
, argv
, "acd:fhmr:t:", longopts
, NULL
)) != -1)
280 change_times
|= CH_ATIME
;
295 no_dereference
= true;
299 change_times
|= CH_MTIME
;
308 if (! posixtime (&newtime
[0].tv_sec
, optarg
,
309 PDS_LEADING_YEAR
| PDS_CENTURY
| PDS_SECONDS
))
310 error (EXIT_FAILURE
, 0, _("invalid date format %s"),
312 newtime
[0].tv_nsec
= 0;
313 newtime
[1] = newtime
[0];
317 case TIME_OPTION
: /* --time */
318 change_times
|= XARGMATCH ("--time", optarg
,
319 time_args
, time_masks
);
322 case_GETOPT_HELP_CHAR
;
324 case_GETOPT_VERSION_CHAR (PROGRAM_NAME
, AUTHORS
);
327 usage (EXIT_FAILURE
);
331 if (change_times
== 0)
332 change_times
= CH_ATIME
| CH_MTIME
;
334 if (date_set
&& (use_ref
|| flex_date
))
336 error (0, 0, _("cannot specify times from more than one source"));
337 usage (EXIT_FAILURE
);
342 struct stat ref_stats
;
343 /* Don't use (no_dereference?lstat:stat) (args), since stat
344 might be an object-like macro. */
345 if (no_dereference
? lstat (ref_file
, &ref_stats
)
346 : stat (ref_file
, &ref_stats
))
347 error (EXIT_FAILURE
, errno
,
348 _("failed to get attributes of %s"), quote (ref_file
));
349 newtime
[0] = get_stat_atime (&ref_stats
);
350 newtime
[1] = get_stat_mtime (&ref_stats
);
354 if (change_times
& CH_ATIME
)
355 get_reldate (&newtime
[0], flex_date
, &newtime
[0]);
356 if (change_times
& CH_MTIME
)
357 get_reldate (&newtime
[1], flex_date
, &newtime
[1]);
366 get_reldate (&newtime
[0], flex_date
, &now
);
367 newtime
[1] = newtime
[0];
370 /* If neither -a nor -m is specified, treat "-d now" as if
371 it were absent; this lets "touch" succeed more often in
372 the presence of restrictive permissions. */
373 if (change_times
== (CH_ATIME
| CH_MTIME
)
374 && newtime
[0].tv_sec
== now
.tv_sec
375 && newtime
[0].tv_nsec
== now
.tv_nsec
)
377 /* Check that it really was "-d now", and not a time
378 stamp that just happens to be the current time. */
379 struct timespec notnow
, notnow1
;
380 notnow
.tv_sec
= now
.tv_sec
^ 1;
381 notnow
.tv_nsec
= now
.tv_nsec
;
382 get_reldate (¬now1
, flex_date
, ¬now
);
383 if (notnow1
.tv_sec
== notnow
.tv_sec
384 && notnow1
.tv_nsec
== notnow
.tv_nsec
)
390 /* The obsolete 'MMDDhhmm[YY]' form is valid IFF there are
391 two or more non-option arguments. */
392 if (!date_set
&& 2 <= argc
- optind
&& posix2_version () < 200112
393 && posixtime (&newtime
[0].tv_sec
, argv
[optind
],
394 PDS_TRAILING_YEAR
| PDS_PRE_2000
))
396 newtime
[0].tv_nsec
= 0;
397 newtime
[1] = newtime
[0];
400 if (! getenv ("POSIXLY_CORRECT"))
402 struct tm
const *tm
= localtime (&newtime
[0].tv_sec
);
404 /* Technically, it appears that even a deliberate attempt to cause
405 the above localtime to return NULL will always fail because our
406 posixtime implementation rejects all dates for which localtime
407 would fail. However, skip the warning if it ever fails. */
410 _("warning: 'touch %s' is obsolete; use "
411 "'touch -t %04ld%02d%02d%02d%02d.%02d'"),
413 tm
->tm_year
+ 1900L, tm
->tm_mon
+ 1, tm
->tm_mday
,
414 tm
->tm_hour
, tm
->tm_min
, tm
->tm_sec
);
422 if (change_times
== (CH_ATIME
| CH_MTIME
))
425 newtime
[1].tv_nsec
= newtime
[0].tv_nsec
= UTIME_NOW
;
430 error (0, 0, _("missing file operand"));
431 usage (EXIT_FAILURE
);
434 for (; optind
< argc
; ++optind
)
435 ok
&= touch (argv
[optind
]);
437 exit (ok
? EXIT_SUCCESS
: EXIT_FAILURE
);