X-Git-Url: http://git.tuebingen.mpg.de/?p=lopsub.git;a=blobdiff_plain;f=lsg.c;h=83a72da5b3b26b949a09f83d251086fed5a9e02d;hp=54b7816eae94fa99e4b145706403a6d7823abf99;hb=HEAD;hpb=9d3fd447f36e1a144a40037d559a92562d120703

diff --git a/lsg.c b/lsg.c
index 54b7816..83a72da 100644
--- a/lsg.c
+++ b/lsg.c
@@ -610,7 +610,7 @@ static char *get_output_path(const char *suffix, const char *arg,
 static void gen_man(struct lls_parse_result *lpr, const char *cmdline)
 {
 	int i;
-	time_t t;
+	time_t t = 0;
 	struct tm *tmp;
 	FILE *out;
 	char *outpath = get_output_path("man",
@@ -626,12 +626,22 @@ static void gen_man(struct lls_parse_result *lpr, const char *cmdline)
 	if (suite.commands[0].name.orig) {
 		char date[200];
 		const char *version_string;
-
 		if (!suite.date) {
-			t = time(NULL);
-			tmp = localtime(&t);
+			/*
+			 * If the SOURCE_DATE_EPOCH environment variable
+			 * contains a positive integer in the time_t range, use
+			 * that instead of the current time. See:
+			 * <https://reproducible-builds.org/specs/source-date-epoch/>
+			 * for more information.
+			 */
+			char *source_date_epoch = getenv("SOURCE_DATE_EPOCH");
+			if (source_date_epoch != NULL)
+				t = strtoll(source_date_epoch, NULL, 10);
+			if (t <= 0)
+				t = time(NULL);
+			tmp = gmtime(&t);
 			if (tmp == NULL) {
-				perror("localtime");
+				perror("gmtime");
 				exit(EXIT_FAILURE);
 			}
 			if (strftime(date, sizeof(date), "%B %Y", tmp) == 0) {