coreutils/touch.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Mini touch implementation for busybox
   4  *
   5  * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
   6  *
   7  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
   8  */
   9
  10 /* BB_AUDIT SUSv3 _NOT_ compliant -- options -a, -m not supported. */
  11 /* http://www.opengroup.org/onlinepubs/007904975/utilities/touch.html */
  12
  13 /* Mar 16, 2003      Manuel Novoa III   (mjn3@codepoet.org)
  14  *
  15  * Previous version called open() and then utime().  While this will be
  16  * be necessary to implement -r and -t, it currently only makes things bigger.
  17  * Also, exiting on a failure was a bug.  All args should be processed.
  18  */
  19
  20 #include "libbb.h"
  21
  22 //config:config TOUCH
  23 //config:       bool "touch"
  24 //config:       default y
  25 //config:       help
  26 //config:         touch is used to create or change the access and/or
  27 //config:         modification timestamp of specified files.
  28 //config:
  29 //config:config FEATURE_TOUCH_SUSV3
  30 //config:       bool "Add support for SUSV3 features (-d -t -r)"
  31 //config:       default y
  32 //config:       depends on TOUCH
  33 //config:       help
  34 //config:         Enable touch to use a reference file or a given date/time argument.
  35
  36 //applet:IF_TOUCH(APPLET_NOFORK(touch, touch, BB_DIR_BIN, BB_SUID_DROP, touch))
  37
  38 //kbuild:lib-$(CONFIG_TOUCH) += touch.o
  39
  40 //usage:#define touch_trivial_usage
  41 //usage:       "[-c]" IF_FEATURE_TOUCH_SUSV3(" [-d DATE] [-t DATE] [-r FILE]") " FILE..."
  42 //usage:#define touch_full_usage "\n\n"
  43 //usage:       "Update the last-modified date on the given FILE[s]\n"
  44 //usage:     "\n        -c      Don't create files"
  45 //usage:        IF_FEATURE_TOUCH_SUSV3(
  46 //usage:     "\n        -d DT   Date/time to use"
  47 //usage:     "\n        -t DT   Date/time to use"
  48 //usage:     "\n        -r FILE Use FILE's date/time"
  49 //usage:        )
  50 //usage:
  51 //usage:#define touch_example_usage
  52 //usage:       "$ ls -l /tmp/foo\n"
  53 //usage:       "/bin/ls: /tmp/foo: No such file or directory\n"
  54 //usage:       "$ touch /tmp/foo\n"
  55 //usage:       "$ ls -l /tmp/foo\n"
  56 //usage:       "-rw-rw-r--    1 andersen andersen        0 Apr 15 01:11 /tmp/foo\n"
  57
  58 /* This is a NOFORK applet. Be very careful! */
  59
  60 /* coreutils implements:
  61  * -a   change only the access time
  62  * -c, --no-create
  63  *      do not create any files
  64  * -d, --date=STRING
  65  *      parse STRING and use it instead of current time
  66  * -f   (ignored, BSD compat)
  67  * -m   change only the modification time
  68  * -r, --reference=FILE
  69  *      use this file's times instead of current time
  70  * -t STAMP
  71  *      use [[CC]YY]MMDDhhmm[.ss] instead of current time
  72  * --time=WORD
  73  *      change the specified time: WORD is access, atime, or use
  74  */
  75
  76 int touch_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  77 int touch_main(int argc UNUSED_PARAM, char **argv)
  78 {
  79         int fd;
  80         int status = EXIT_SUCCESS;
  81         int opts;
  82 #if ENABLE_FEATURE_TOUCH_SUSV3
  83 # if ENABLE_LONG_OPTS
  84         static const char touch_longopts[] ALIGN1 =
  85                 /* name, has_arg, val */
  86                 "no-create\0"         No_argument       "c"
  87                 "reference\0"         Required_argument "r"
  88                 "date\0"              Required_argument "d"
  89         ;
  90 # endif
  91         char *reference_file = NULL;
  92         char *date_str = NULL;
  93         struct timeval timebuf[2];
  94         timebuf[1].tv_usec = timebuf[0].tv_usec = 0;
  95 #else
  96 # define reference_file NULL
  97 # define date_str       NULL
  98 # define timebuf        ((struct timeval*)NULL)
  99 #endif
 100
 101 #if ENABLE_FEATURE_TOUCH_SUSV3 && ENABLE_LONG_OPTS
 102         applet_long_options = touch_longopts;
 103 #endif
 104         /* -d and -t both set time. In coreutils,
 105          * accepted data format differs a bit between -d and -t.
 106          * We accept the same formats for both */
 107         opts = getopt32(argv, "c" IF_FEATURE_TOUCH_SUSV3("r:d:t:")
 108                                 /*ignored:*/ "fma"
 109                                 IF_FEATURE_TOUCH_SUSV3(, &reference_file)
 110                                 IF_FEATURE_TOUCH_SUSV3(, &date_str)
 111                                 IF_FEATURE_TOUCH_SUSV3(, &date_str)
 112         );
 113
 114         opts &= 1; /* only -c bit is left */
 115         argv += optind;
 116         if (!*argv) {
 117                 bb_show_usage();
 118         }
 119
 120         if (reference_file) {
 121                 struct stat stbuf;
 122                 xstat(reference_file, &stbuf);
 123                 timebuf[1].tv_sec = timebuf[0].tv_sec = stbuf.st_mtime;
 124         }
 125
 126         if (date_str) {
 127                 struct tm tm_time;
 128                 time_t t;
 129
 130                 //memset(&tm_time, 0, sizeof(tm_time));
 131                 /* Better than memset: makes "HH:MM" dates meaningful */
 132                 time(&t);
 133                 localtime_r(&t, &tm_time);
 134                 parse_datestr(date_str, &tm_time);
 135
 136                 /* Correct any day of week and day of year etc. fields */
 137                 tm_time.tm_isdst = -1;  /* Be sure to recheck dst */
 138                 t = validate_tm_time(date_str, &tm_time);
 139
 140                 timebuf[1].tv_sec = timebuf[0].tv_sec = t;
 141         }
 142
 143         do {
 144                 if (utimes(*argv, (reference_file || date_str) ? timebuf : NULL) != 0) {
 145                         if (errno == ENOENT) { /* no such file */
 146                                 if (opts) { /* creation is disabled, so ignore */
 147                                         continue;
 148                                 }
 149                                 /* Try to create the file */
 150                                 fd = open(*argv, O_RDWR | O_CREAT, 0666);
 151                                 if (fd >= 0) {
 152                                         xclose(fd);
 153                                         if (reference_file || date_str)
 154                                                 utimes(*argv, timebuf);
 155                                         continue;
 156                                 }
 157                         }
 158                         status = EXIT_FAILURE;
 159                         bb_simple_perror_msg(*argv);
 160                 }
 161         } while (*++argv);
 162
 163         return status;
 164 }