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_NODEREF
  30 //config:       bool "Add support for -h"
  31 //config:       default y
  32 //config:       depends on TOUCH
  33 //config:       help
  34 //config:         Enable touch to have the -h option.
  35 //config:         This requires libc support for lutimes() function.
  36 //config:
  37 //config:config FEATURE_TOUCH_SUSV3
  38 //config:       bool "Add support for SUSV3 features (-d -t -r)"
  39 //config:       default y
  40 //config:       depends on TOUCH
  41 //config:       help
  42 //config:         Enable touch to use a reference file or a given date/time argument.
  43
  44 //applet:IF_TOUCH(APPLET_NOFORK(touch, touch, BB_DIR_BIN, BB_SUID_DROP, touch))
  45
  46 //kbuild:lib-$(CONFIG_TOUCH) += touch.o
  47
  48 //usage:#define touch_trivial_usage
  49 //usage:       "[-c]" IF_FEATURE_TOUCH_SUSV3(" [-d DATE] [-t DATE] [-r FILE]") " FILE..."
  50 //usage:#define touch_full_usage "\n\n"
  51 //usage:       "Update the last-modified date on the given FILE[s]\n"
  52 //usage:     "\n        -c      Don't create files"
  53 //usage:        IF_FEATURE_TOUCH_NODEREF(
  54 //usage:     "\n        -h      Don't follow links"
  55 //usage:        )
  56 //usage:        IF_FEATURE_TOUCH_SUSV3(
  57 //usage:     "\n        -d DT   Date/time to use"
  58 //usage:     "\n        -t DT   Date/time to use"
  59 //usage:     "\n        -r FILE Use FILE's date/time"
  60 //usage:        )
  61 //usage:
  62 //usage:#define touch_example_usage
  63 //usage:       "$ ls -l /tmp/foo\n"
  64 //usage:       "/bin/ls: /tmp/foo: No such file or directory\n"
  65 //usage:       "$ touch /tmp/foo\n"
  66 //usage:       "$ ls -l /tmp/foo\n"
  67 //usage:       "-rw-rw-r--    1 andersen andersen        0 Apr 15 01:11 /tmp/foo\n"
  68
  69 /* This is a NOFORK applet. Be very careful! */
  70
  71 /* coreutils implements:
  72  * -a   change only the access time
  73  * -c, --no-create
  74  *      do not create any files
  75  * -d, --date=STRING
  76  *      parse STRING and use it instead of current time
  77  * -f   (ignored, BSD compat)
  78  * -m   change only the modification time
  79  * -h, --no-dereference
  80  * -r, --reference=FILE
  81  *      use this file's times instead of current time
  82  * -t STAMP
  83  *      use [[CC]YY]MMDDhhmm[.ss] instead of current time
  84  * --time=WORD
  85  *      change the specified time: WORD is access, atime, or use
  86  */
  87
  88 int touch_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  89 int touch_main(int argc UNUSED_PARAM, char **argv)
  90 {
  91         int fd;
  92         int status = EXIT_SUCCESS;
  93         int opts;
  94         enum {
  95                 OPT_c = (1 << 0),
  96                 OPT_r = (1 << 1) * ENABLE_FEATURE_TOUCH_SUSV3,
  97                 OPT_d = (1 << 2) * ENABLE_FEATURE_TOUCH_SUSV3,
  98                 OPT_t = (1 << 3) * ENABLE_FEATURE_TOUCH_SUSV3,
  99                 OPT_h = (1 << 4) * ENABLE_FEATURE_TOUCH_NODEREF,
 100         };
 101 #if ENABLE_FEATURE_TOUCH_SUSV3
 102 # if ENABLE_LONG_OPTS
 103         static const char touch_longopts[] ALIGN1 =
 104                 /* name, has_arg, val */
 105                 "no-create\0"         No_argument       "c"
 106                 "reference\0"         Required_argument "r"
 107                 "date\0"              Required_argument "d"
 108                 IF_FEATURE_TOUCH_NODEREF("no-dereference\0" No_argument "h")
 109         ;
 110 # endif
 111         char *reference_file = NULL;
 112         char *date_str = NULL;
 113         struct timeval timebuf[2];
 114         timebuf[1].tv_usec = timebuf[0].tv_usec = 0;
 115 #else
 116 # define reference_file NULL
 117 # define date_str       NULL
 118 # define timebuf        ((struct timeval*)NULL)
 119 #endif
 120
 121 #if ENABLE_FEATURE_TOUCH_SUSV3 && ENABLE_LONG_OPTS
 122         applet_long_options = touch_longopts;
 123 #endif
 124         /* -d and -t both set time. In coreutils,
 125          * accepted data format differs a bit between -d and -t.
 126          * We accept the same formats for both */
 127         opts = getopt32(argv, "c" IF_FEATURE_TOUCH_SUSV3("r:d:t:")
 128                                 IF_FEATURE_TOUCH_NODEREF("h")
 129                                 /*ignored:*/ "fma"
 130                                 IF_FEATURE_TOUCH_SUSV3(, &reference_file)
 131                                 IF_FEATURE_TOUCH_SUSV3(, &date_str)
 132                                 IF_FEATURE_TOUCH_SUSV3(, &date_str)
 133         );
 134
 135         argv += optind;
 136         if (!*argv) {
 137                 bb_show_usage();
 138         }
 139
 140         if (reference_file) {
 141                 struct stat stbuf;
 142                 xstat(reference_file, &stbuf);
 143                 timebuf[1].tv_sec = timebuf[0].tv_sec = stbuf.st_mtime;
 144                 /* Can use .st_mtim.tv_nsec
 145                  * (or is it .st_mtimensec?? see date.c)
 146                  * to set microseconds too.
 147                  */
 148         }
 149
 150         if (date_str) {
 151                 struct tm tm_time;
 152                 time_t t;
 153
 154                 //memset(&tm_time, 0, sizeof(tm_time));
 155                 /* Better than memset: makes "HH:MM" dates meaningful */
 156                 time(&t);
 157                 localtime_r(&t, &tm_time);
 158                 parse_datestr(date_str, &tm_time);
 159
 160                 /* Correct any day of week and day of year etc. fields */
 161                 tm_time.tm_isdst = -1;  /* Be sure to recheck dst */
 162                 t = validate_tm_time(date_str, &tm_time);
 163
 164                 timebuf[1].tv_sec = timebuf[0].tv_sec = t;
 165         }
 166
 167         do {
 168                 int result;
 169                 result = (
 170 #if ENABLE_FEATURE_TOUCH_NODEREF
 171                         (opts & OPT_h) ? lutimes :
 172 #endif
 173                         utimes)(*argv, (reference_file || date_str) ? timebuf : NULL);
 174                 if (result != 0) {
 175                         if (errno == ENOENT) { /* no such file? */
 176                                 if (opts & OPT_c) {
 177                                         /* Creation is disabled, so ignore */
 178                                         continue;
 179                                 }
 180                                 /* Try to create the file */
 181                                 fd = open(*argv, O_RDWR | O_CREAT, 0666);
 182                                 if (fd >= 0) {
 183                                         xclose(fd);
 184                                         if (reference_file || date_str)
 185                                                 utimes(*argv, timebuf);
 186                                         continue;
 187                                 }
 188                         }
 189                         status = EXIT_FAILURE;
 190                         bb_simple_perror_msg(*argv);
 191                 }
 192         } while (*++argv);
 193
 194         return status;
 195 }