1 files changed, 119 insertions, 0 deletions
diff --git a/t/helper/test-chmtime.c b/t/helper/test-chmtime.c
new file mode 100644
index 0000000000..dfe8a83261
--- /dev/null
+++ b/t/helper/test-chmtime.c
@@ -0,0 +1,119 @@
+/*
+ * 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;
+}