root/test-chmtime.c

DEFINITIONS

1. timespec_arg
2. main

/*
 * This program can either change modification time of the given
 * file(s) or just print it. The program does not change atime or
 * ctime (their values are explicitly preserved).
 *
 * The mtime can be changed to an absolute value:
 *
 *      test-chmtime =<seconds> file...
 *
 * Relative to the current time as returned by time(3):
 *
 *      test-chmtime =+<seconds> (or =-<seconds>) file...
 *
 * Or relative to the current mtime of the file:
 *
 *      test-chmtime <seconds> file...
 *      test-chmtime +<seconds> (or -<seconds>) file...
 *
 * Examples:
 *
 * To just print the mtime use --verbose and set the file mtime offset to 0:
 *
 *      test-chmtime -v +0 file
 *
 * To set the mtime to current time:
 *
 *      test-chmtime =+0 file
 *
 */
#include "git-compat-util.h"
#include <utime.h>

static const char usage_str[] = "-v|--verbose (+|=|=+|=-|-)<seconds> <file>...";

static int timespec_arg(const char *arg, long int *set_time, int *set_eq)
{
        char *test;
        const char *timespec = arg;
        *set_eq = (*timespec == '=') ? 1 : 0;
        if (*set_eq) {
                timespec++;
                if (*timespec == '+') {
                        *set_eq = 2; /* relative "in the future" */
                        timespec++;
                }
        }
        *set_time = strtol(timespec, &test, 10);
        if (*test) {
                fprintf(stderr, "Not a base-10 integer: %s\n", arg + 1);
                return 0;
        }
        if ((*set_eq && *set_time < 0) || *set_eq == 2) {
                time_t now = time(NULL);
                *set_time += now;
        }
        return 1;
}

int main(int argc, char *argv[])
{
        static int verbose;

        int i = 1;
        /* no mtime change by default */
        int set_eq = 0;
        long int set_time = 0;

        if (argc < 3)
                goto usage;

        if (strcmp(argv[i], "--verbose") == 0 || strcmp(argv[i], "-v") == 0) {
                verbose = 1;
                ++i;
        }
        if (timespec_arg(argv[i], &set_time, &set_eq))
                ++i;
        else
                goto usage;

        for (; i < argc; i++) {
                struct stat sb;
                struct utimbuf utb;

                if (stat(argv[i], &sb) < 0) {
                        fprintf(stderr, "Failed to stat %s: %s\n",
                                argv[i], strerror(errno));
                        return 1;
                }

#ifdef GIT_WINDOWS_NATIVE
                if (!(sb.st_mode & S_IWUSR) &&
                                chmod(argv[i], sb.st_mode | S_IWUSR)) {
                        fprintf(stderr, "Could not make user-writable %s: %s",
                                argv[i], strerror(errno));
                        return 1;
                }
#endif

                utb.actime = sb.st_atime;
                utb.modtime = set_eq ? set_time : sb.st_mtime + set_time;

                if (verbose) {
                        uintmax_t mtime = utb.modtime < 0 ? 0: utb.modtime;
                        printf("%"PRIuMAX"\t%s\n", mtime, argv[i]);
                }

                if (utb.modtime != sb.st_mtime && utime(argv[i], &utb) < 0) {
                        fprintf(stderr, "Failed to modify time on %s: %s\n",
                                argv[i], strerror(errno));
                        return 1;
                }
        }

        return 0;

usage:
        fprintf(stderr, "usage: %s %s\n", argv[0], usage_str);
        return 1;
}