git log: don't do merge diffs by default

diff --git a/describe.c b/describe.c
index e1b6588c9b8d0bd70702a56e182b2352dacc4386..ff65742615cb6862d3699e4f301d671a7eadc2e2 100644 (file)
--- a/describe.c
+++ b/describe.c
@@ -5,14 +5,19 @@
 
 #define SEEN (1u << 0)
 
-static const char describe_usage[] = "git-describe [--all] <committish>*";
+static const char describe_usage[] =
+"git-describe [--all] [--tags] [--abbrev=<n>] <committish>*";
 
 static int all = 0;    /* Default to annotated tags only */
+static int tags = 0;   /* But allow any tags if --tags is specified */
+
+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)
@@ -28,13 +33,16 @@ 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) {
@@ -48,17 +56,32 @@ 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) {
-               struct object *object;
-               if (strncmp(path, "refs/tags/", 10))
+               if (!prio)
                        return 0;
-               object = parse_object(sha1);
-               if (object->type != tag_type)
+               if (!tags && prio < 2)
                        return 0;
        }
-       add_to_known_names(all ? path : path + 10, commit);
+       add_to_known_names(all ? path + 5 : path + 10, commit, prio);
        return 0;
 }
 
@@ -68,15 +91,26 @@ 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;
 }
 
-static void describe(struct commit *cmit)
+static void describe(char *arg, int last_one)
 {
+       unsigned char sha1[20];
+       struct commit *cmit;
        struct commit_list *list;
        static int initialized = 0;
        struct commit_name *n;
 
+       if (get_sha1(arg, sha1) < 0)
+               usage(describe_usage);
+       cmit = lookup_commit_reference(sha1);
+       if (!cmit)
+               usage(describe_usage);
+
        if (!initialized) {
                initialized = 1;
                for_each_ref(get_name);
@@ -95,10 +129,14 @@ static void describe(struct commit *cmit)
                struct commit *c = pop_most_recent_commit(&list, SEEN);
                n = match(c);
                if (n) {
-                       printf("%s-g%.8s\n", n->path, sha1_to_hex(cmit->object.sha1));
+                       printf("%s-g%s\n", n->path,
+                              find_unique_abbrev(cmit->object.sha1, abbrev));
+                       if (!last_one)
+                               clear_commit_marks(cmit, SEEN);
                        return;
                }
        }
+       die("cannot describe '%s'", sha1_to_hex(cmit->object.sha1));
 }
 
 int main(int argc, char **argv)
@@ -107,19 +145,29 @@ int main(int argc, char **argv)
 
        for (i = 1; i < argc; i++) {
                const char *arg = argv[i];
-               unsigned char sha1[20];
-               struct commit *cmit;
 
-               if (!strcmp(arg, "--all")) {
+               if (*arg != '-')
+                       break;
+               else if (!strcmp(arg, "--all"))
                        all = 1;
-                       continue;
+               else if (!strcmp(arg, "--tags"))
+                       tags = 1;
+               else if (!strncmp(arg, "--abbrev=", 9)) {
+                       abbrev = strtoul(arg + 9, NULL, 10);
+                       if (abbrev < MINIMUM_ABBREV || 40 <= abbrev)
+                               abbrev = DEFAULT_ABBREV;
                }
-               if (get_sha1(arg, sha1) < 0)
-                       usage(describe_usage);
-               cmit = lookup_commit_reference(sha1);
-               if (!cmit)
+               else
                        usage(describe_usage);
-               describe(cmit);
        }
+
+       if (i == argc)
+               describe("HEAD", 1);
+       else
+               while (i < argc) {
+                       describe(argv[i], (i == argc - 1));
+                       i++;
+               }
+
        return 0;
 }