test-chmtime.c

   1 /*
   2  * This program can either change modification time of the given
   3  * file(s) or just print it. The program does not change atime nor
   4  * ctime (their values are explicitely preserved).
   5  *
   6  * The mtime can be changed to an absolute value:
   7  *
   8  *      test-chmtime =<seconds> file...
   9  *
  10  * Relative to the current time as returned by time(3):
  11  *
  12  *      test-chmtime =+<seconds> (or =-<seconds>) file...
  13  *
  14  * Or relative to the current mtime of the file:
  15  *
  16  *      test-chmtime <seconds> file...
  17  *      test-chmtime +<seconds> (or -<seconds>) file...
  18  *
  19  * Examples:
  20  *
  21  * To just print the mtime use --verbose and set the file mtime offset to 0:
  22  *
  23  *      test-chmtime -v +0 file
  24  *
  25  * To set the mtime to current time:
  26  *
  27  *      test-chmtime =+0 file
  28  *
  29  */
  30 #include "git-compat-util.h"
  31 #include <utime.h>
  32
  33 static const char usage_str[] = "-v|--verbose (+|=|=+|=-|-)<seconds> <file>...";
  34
  35 static int timespec_arg(const char *arg, long int *set_time, int *set_eq)
  36 {
  37         char *test;
  38         const char *timespec = arg;
  39         *set_eq = (*timespec == '=') ? 1 : 0;
  40         if (*set_eq) {
  41                 timespec++;
  42                 if (*timespec == '+') {
  43                         *set_eq = 2; /* relative "in the future" */
  44                         timespec++;
  45                 }
  46         }
  47         *set_time = strtol(timespec, &test, 10);
  48         if (*test) {
  49                 fprintf(stderr, "Not a base-10 integer: %s\n", arg + 1);
  50                 return 0;
  51         }
  52         if ((*set_eq && *set_time < 0) || *set_eq == 2) {
  53                 time_t now = time(NULL);
  54                 *set_time += now;
  55         }
  56         return 1;
  57 }
  58
  59 int main(int argc, const char *argv[])
  60 {
  61         static int verbose;
  62
  63         int i = 1;
  64         /* no mtime change by default */
  65         int set_eq = 0;
  66         long int set_time = 0;
  67
  68         if (argc < 3)
  69                 goto usage;
  70
  71         if (strcmp(argv[i], "--verbose") == 0 || strcmp(argv[i], "-v") == 0) {
  72                 verbose = 1;
  73                 ++i;
  74         }
  75         if (timespec_arg(argv[i], &set_time, &set_eq))
  76                 ++i;
  77         else
  78                 goto usage;
  79
  80         for (; i < argc; i++) {
  81                 struct stat sb;
  82                 struct utimbuf utb;
  83
  84                 if (stat(argv[i], &sb) < 0) {
  85                         fprintf(stderr, "Failed to stat %s: %s\n",
  86                                 argv[i], strerror(errno));
  87                         return -1;
  88                 }
  89
  90                 utb.actime = sb.st_atime;
  91                 utb.modtime = set_eq ? set_time : sb.st_mtime + set_time;
  92
  93                 if (verbose) {
  94                         uintmax_t mtime = utb.modtime < 0 ? 0: utb.modtime;
  95                         printf("%"PRIuMAX"\t%s\n", mtime, argv[i]);
  96                 }
  97
  98                 if (utb.modtime != sb.st_mtime && utime(argv[i], &utb) < 0) {
  99                         fprintf(stderr, "Failed to modify time on %s: %s\n",
 100                                 argv[i], strerror(errno));
 101                         return -1;
 102                 }
 103         }
 104
 105         return 0;
 106
 107 usage:
 108         fprintf(stderr, "Usage: %s %s\n", argv[0], usage_str);
 109         return -1;
 110 }