git am: Display some help text when patch is empty

diff --git a/tag.c b/tag.c
index ceb86557c5eedb03cbdc81929b7d109b44d440d5..85607c219e25d63b0d1f3344649104c60f5b96e2 100644 (file)
--- a/tag.c
+++ b/tag.c
@@ -36,6 +36,23 @@ struct tag *lookup_tag(const unsigned char *sha1)
         return (struct tag *) obj;
 }
 
+static unsigned long parse_tag_date(const char *buf, const char *tail)
+{
+       const char *dateptr;
+
+       while (buf < tail && *buf++ != '>')
+               /* nada */;
+       if (buf >= tail)
+               return 0;
+       dateptr = buf;
+       while (buf < tail && *buf++ != '\n')
+               /* nada */;
+       if (buf >= tail)
+               return 0;
+       /* dateptr < buf && buf[-1] == '\n', so strtoul will stop at buf-1 */
+       return strtoul(dateptr, NULL, 10);
+}
+
 int parse_tag_buffer(struct tag *item, void *data, unsigned long size)
 {
        unsigned char sha1[20];
@@ -86,6 +103,11 @@ int parse_tag_buffer(struct tag *item, void *data, unsigned long size)
        item->tag = xmemdupz(bufptr, nl - bufptr);
        bufptr = nl + 1;
 
+       if (!prefixcmp(bufptr, "tagger "))
+               item->date = parse_tag_date(bufptr, tail);
+       else
+               item->date = 0;
+
        return 0;
 }