ustar: Move SOURCE_DATE_EPOCH code to opk/write

This way it runs only once (without resorting to static variables)
across all headers in all ustar archives.  Also, opk/write now prints an
informative error message.

1 files changed, 27 insertions, 1 deletions

diff --git a/src/opk/write.c b/src/opk/write.c
index 1b490ee..93ddc74 100644
--- a/src/opk/write.c
+++ b/src/opk/write.c
@@ -20,6 +20,7 @@
 #include <grp.h>
 #include <pwd.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
 #include "../defs.h"
 #include "../dirent.h"
@@ -41,16 +42,41 @@ _opkg_opk_opk_write_file(void *user_data, size_t size)
 	}
 }
 
+static int
+_opkg_opk_opk_source_date_epoch(int64_t *mtime)
+{
+	char *env;
+	char *end;
+
+	env = getenv("SOURCE_DATE_EPOCH");
+	if (env == NULL) {
+		return OPKG_OPK_ERROR;
+	}
+	*mtime = strtol(env, &end, 10);
+	if (*end != '\0') {
+		return OPKG_OPK_ERROR;
+	}
+	return OPKG_OPK_OK;
+}
+
 int
 opkg_opk_opk_write(struct opkg_opk_opk *opk, const char *file_name)
 {
 	int                     ret;
+	int64_t                 mtime;
 	struct opkg_opk_dirent  dirent;
 	char                   *buffer;
 	size_t                  size;
 
 	ret = OPKG_OPK_OK;
 
+	if (_opkg_opk_opk_source_date_epoch(&mtime) == OPKG_OPK_ERROR) {
+		fputs(_("Error: Missing or invalid SOURCE_DATE_EPOCH\n"),
+				stderr);
+		ret = OPKG_OPK_ERROR;
+		goto out0;
+	}
+
 	/* Open outer archive. */
 	opk->file = fopen(file_name, "wb");
 	if (opk->file == NULL) {
@@ -85,7 +111,7 @@ opkg_opk_opk_write(struct opkg_opk_opk *opk, const char *file_name)
 	if (opkg_opk_ustar_write_header(opk->outer_ustar, &dirent, 0644,
 				0, getpwuid(0)->pw_name,
 				0, getgrgid(0)->gr_name,
-				4, '-', NULL) != OPKG_OPK_OK) {
+				4, mtime, '-', NULL) != OPKG_OPK_OK) {
 		fputs(_("Error: Failed to write header\n"), stderr);
 		ret = OPKG_OPK_ERROR;
 		goto out3;