describe: do not silently ignore indescribable commits

diff --git a/describe.c b/describe.c
index ee38f5f5d8791646cd6ca0f1d2570d793afa78a9..5548a16e4d97690e207a6e7cd0699aa8de73f81f 100644 (file)
--- a/describe.c
+++ b/describe.c
@@ -17,7 +17,8 @@ static int abbrev = DEFAULT_ABBREV;
 static int names = 0, allocs = 0;
 static struct commit_name {
        const struct commit *commit;
-       char path[];
+       int prio; /* annotated tag = 2, tag = 1, head = 0 */
+       char path[FLEX_ARRAY]; /* more */
 } **name_array = NULL;
 
 static struct commit_name *match(struct commit *cmit)
@@ -33,13 +34,16 @@ static struct commit_name *match(struct commit *cmit)
        return NULL;
 }
 
-static void add_to_known_names(const char *path, const struct commit *commit)
+static void add_to_known_names(const char *path,
+                              const struct commit *commit,
+                              int prio)
 {
        int idx;
        int len = strlen(path)+1;
        struct commit_name *name = xmalloc(sizeof(struct commit_name) + len);
 
        name->commit = commit;
+       name->prio = prio; 
        memcpy(name->path, path, len);
        idx = names;
        if (idx >= allocs) {
@@ -53,23 +57,32 @@ static void add_to_known_names(const char *path, const struct commit *commit)
 static int get_name(const char *path, const unsigned char *sha1)
 {
        struct commit *commit = lookup_commit_reference_gently(sha1, 1);
+       struct object *object;
+       int prio;
+
        if (!commit)
                return 0;
+       object = parse_object(sha1);
        /* If --all, then any refs are used.
         * If --tags, then any tags are used.
         * Otherwise only annotated tags are used.
         */
+       if (!strncmp(path, "refs/tags/", 10)) {
+               if (object->type == tag_type)
+                       prio = 2;
+               else
+                       prio = 1;
+       }
+       else
+               prio = 0;
+
        if (!all) {
-               if (strncmp(path, "refs/tags/", 10))
+               if (!prio)
+                       return 0;
+               if (!tags && prio < 2)
                        return 0;
-               if (!tags) {
-                       struct object *object;
-                       object = parse_object(sha1);
-                       if (object->type != tag_type)
-                               return 0;
-               }
        }
-       add_to_known_names(all ? path : path + 10, commit);
+       add_to_known_names(all ? path + 5 : path + 10, commit, prio);
        return 0;
 }
 
@@ -79,6 +92,9 @@ static int compare_names(const void *_a, const void *_b)
        struct commit_name *b = *(struct commit_name **)_b;
        unsigned long a_date = a->commit->date;
        unsigned long b_date = b->commit->date;
+
+       if (a->prio != b->prio)
+               return b->prio - a->prio;
        return (a_date > b_date) ? -1 : (a_date == b_date) ? 0 : 1;
 }
 
@@ -108,9 +124,11 @@ static void describe(struct commit *cmit)
                if (n) {
                        printf("%s-g%s\n", n->path,
                               find_unique_abbrev(cmit->object.sha1, abbrev));
+                       clear_commit_marks(cmit, SEEN);
                        return;
                }
        }
+       die("cannot describe '%s'", sha1_to_hex(cmit->object.sha1));
 }
 
 int main(int argc, char **argv)