1 files changed, 117 insertions, 44 deletions

diff --git a/builtin/name-rev.c b/builtin/name-rev.c
index 8bdc3eaa6f..f1cb45c227 100644
--- a/builtin/name-rev.c
+++ b/builtin/name-rev.c
@@ -1,33 +1,91 @@
 #include "builtin.h"
 #include "cache.h"
+#include "repository.h"
+#include "config.h"
 #include "commit.h"
 #include "tag.h"
 #include "refs.h"
 #include "parse-options.h"
 #include "sha1-lookup.h"
+#include "commit-slab.h"
 
 #define CUTOFF_DATE_SLOP 86400 /* one day */
 
 typedef struct rev_name {
 	const char *tip_name;
-	unsigned long taggerdate;
+	timestamp_t taggerdate;
 	int generation;
 	int distance;
+	int from_tag;
 } rev_name;
 
-static long cutoff = LONG_MAX;
+define_commit_slab(commit_rev_name, struct rev_name *);
+
+static timestamp_t cutoff = TIME_MAX;
+static struct commit_rev_name rev_names;
 
 /* How many generations are maximally preferred over _one_ merge traversal? */
 #define MERGE_TRAVERSAL_WEIGHT 65535
 
+static struct rev_name *get_commit_rev_name(struct commit *commit)
+{
+	struct rev_name **slot = commit_rev_name_peek(&rev_names, commit);
+
+	return slot ? *slot : NULL;
+}
+
+static void set_commit_rev_name(struct commit *commit, struct rev_name *name)
+{
+	*commit_rev_name_at(&rev_names, commit) = name;
+}
+
+static int is_better_name(struct rev_name *name,
+			  const char *tip_name,
+			  timestamp_t taggerdate,
+			  int generation,
+			  int distance,
+			  int from_tag)
+{
+	/*
+	 * When comparing names based on tags, prefer names
+	 * based on the older tag, even if it is farther away.
+	 */
+	if (from_tag && name->from_tag)
+		return (name->taggerdate > taggerdate ||
+			(name->taggerdate == taggerdate &&
+			 name->distance > distance));
+
+	/*
+	 * We know that at least one of them is a non-tag at this point.
+	 * favor a tag over a non-tag.
+	 */
+	if (name->from_tag != from_tag)
+		return from_tag;
+
+	/*
+	 * We are now looking at two non-tags.  Tiebreak to favor
+	 * shorter hops.
+	 */
+	if (name->distance != distance)
+		return name->distance > distance;
+
+	/* ... or tiebreak to favor older date */
+	if (name->taggerdate != taggerdate)
+		return name->taggerdate > taggerdate;
+
+	/* keep the current one if we cannot decide */
+	return 0;
+}
+
 static void name_rev(struct commit *commit,
-		const char *tip_name, unsigned long taggerdate,
-		int generation, int distance,
+		const char *tip_name, timestamp_t taggerdate,
+		int generation, int distance, int from_tag,
 		int deref)
 {
-	struct rev_name *name = (struct rev_name *)commit->util;
+	struct rev_name *name = get_commit_rev_name(commit);
 	struct commit_list *parents;
 	int parent_number = 1;
+	char *to_free = NULL;
 
 	parse_commit(commit);
 
@@ -35,7 +93,7 @@ static void name_rev(struct commit *commit,
 		return;
 
 	if (deref) {
-		tip_name = xstrfmt("%s^0", tip_name);
+		tip_name = to_free = xstrfmt("%s^0", tip_name);
 
 		if (generation)
 			die("generation: %d, but deref?", generation);
@@ -43,18 +101,20 @@ static void name_rev(struct commit *commit,
 
 	if (name == NULL) {
 		name = xmalloc(sizeof(rev_name));
-		commit->util = name;
+		set_commit_rev_name(commit, name);
 		goto copy_data;
-	} else if (name->taggerdate > taggerdate ||
-			(name->taggerdate == taggerdate &&
-			 name->distance > distance)) {
+	} else if (is_better_name(name, tip_name, taggerdate,
+				  generation, distance, from_tag)) {
 copy_data:
 		name->tip_name = tip_name;
 		name->taggerdate = taggerdate;
 		name->generation = generation;
 		name->distance = distance;
-	} else
+		name->from_tag = from_tag;
+	} else {
+		free(to_free);
 		return;
+	}
 
 	for (parents = commit->parents;
 			parents;
@@ -72,10 +132,12 @@ copy_data:
 						   parent_number);
 
 			name_rev(parents->item, new_name, taggerdate, 0,
-				distance + MERGE_TRAVERSAL_WEIGHT, 0);
+				 distance + MERGE_TRAVERSAL_WEIGHT,
+				 from_tag, 0);
 		} else {
 			name_rev(parents->item, tip_name, taggerdate,
-				generation + 1, distance + 1, 0);
+				 generation + 1, distance + 1,
+				 from_tag, 0);
 		}
 	}
 }
@@ -85,7 +147,7 @@ static int subpath_matches(const char *path, const char *filter)
 	const char *subpath = path;
 
 	while (subpath) {
-		if (!wildmatch(filter, subpath, 0, NULL))
+		if (!wildmatch(filter, subpath, 0))
 			return subpath - path;
 		subpath = strchr(subpath, '/');
 		if (subpath)
@@ -114,7 +176,7 @@ struct name_ref_data {
 
 static struct tip_table {
 	struct tip_table_entry {
-		unsigned char sha1[20];
+		struct object_id oid;
 		const char *refname;
 	} *table;
 	int nr;
@@ -122,13 +184,13 @@ static struct tip_table {
 	int sorted;
 } tip_table;
 
-static void add_to_tip_table(const unsigned char *sha1, const char *refname,
+static void add_to_tip_table(const struct object_id *oid, const char *refname,
 			     int shorten_unambiguous)
 {
 	refname = name_ref_abbrev(refname, shorten_unambiguous);
 
 	ALLOC_GROW(tip_table.table, tip_table.nr + 1, tip_table.alloc);
-	hashcpy(tip_table.table[tip_table.nr].sha1, sha1);
+	oidcpy(&tip_table.table[tip_table.nr].oid, oid);
 	tip_table.table[tip_table.nr].refname = xstrdup(refname);
 	tip_table.nr++;
 	tip_table.sorted = 0;
@@ -137,16 +199,16 @@ static void add_to_tip_table(const unsigned char *sha1, const char *refname,
 static int tipcmp(const void *a_, const void *b_)
 {
 	const struct tip_table_entry *a = a_, *b = b_;
-	return hashcmp(a->sha1, b->sha1);
+	return oidcmp(&a->oid, &b->oid);
 }
 
 static int name_ref(const char *path, const struct object_id *oid, int flags, void *cb_data)
 {
-	struct object *o = parse_object(oid->hash);
+	struct object *o = parse_object(the_repository, oid);
 	struct name_ref_data *data = cb_data;
 	int can_abbreviate_output = data->tags_only && data->name_only;
 	int deref = 0;
-	unsigned long taggerdate = ULONG_MAX;
+	timestamp_t taggerdate = TIME_MAX;
 
 	if (data->tags_only && !starts_with(path, "refs/tags/"))
 		return 0;
@@ -194,21 +256,25 @@ static int name_ref(const char *path, const struct object_id *oid, int flags, vo
 			return 0;
 	}
 
-	add_to_tip_table(oid->hash, path, can_abbreviate_output);
+	add_to_tip_table(oid, path, can_abbreviate_output);
 
 	while (o && o->type == OBJ_TAG) {
 		struct tag *t = (struct tag *) o;
 		if (!t->tagged)
 			break; /* broken repository */
-		o = parse_object(t->tagged->oid.hash);
+		o = parse_object(the_repository, &t->tagged->oid);
 		deref = 1;
 		taggerdate = t->date;
 	}
 	if (o && o->type == OBJ_COMMIT) {
 		struct commit *commit = (struct commit *)o;
+		int from_tag = starts_with(path, "refs/tags/");
 
+		if (taggerdate == TIME_MAX)
+			taggerdate = ((struct commit *)o)->date;
 		path = name_ref_abbrev(path, can_abbreviate_output);
-		name_rev(commit, xstrdup(path), taggerdate, 0, 0, deref);
+		name_rev(commit, xstrdup(path), taggerdate, 0, 0,
+			 from_tag, deref);
 	}
 	return 0;
 }
@@ -216,7 +282,7 @@ static int name_ref(const char *path, const struct object_id *oid, int flags, vo
 static const unsigned char *nth_tip_table_ent(size_t ix, void *table_)
 {
 	struct tip_table_entry *table = table_;
-	return table[ix].sha1;
+	return table[ix].oid.hash;
 }
 
 static const char *get_exact_ref_match(const struct object *o)
@@ -238,17 +304,16 @@ static const char *get_exact_ref_match(const struct object *o)
 	return NULL;
 }
 
-/* returns a static buffer */
-static const char *get_rev_name(const struct object *o)
+/* may return a constant string or use "buf" as scratch space */
+static const char *get_rev_name(const struct object *o, struct strbuf *buf)
 {
-	static char buffer[1024];
 	struct rev_name *n;
 	struct commit *c;
 
 	if (o->type != OBJ_COMMIT)
 		return get_exact_ref_match(o);
 	c = (struct commit *) o;
-	n = c->util;
+	n = get_commit_rev_name(c);
 	if (!n)
 		return NULL;
 
@@ -258,10 +323,9 @@ static const char *get_rev_name(const struct object *o)
 		int len = strlen(n->tip_name);
 		if (len > 2 && !strcmp(n->tip_name + len - 2, "^0"))
 			len -= 2;
-		snprintf(buffer, sizeof(buffer), "%.*s~%d", len, n->tip_name,
-				n->generation);
-
-		return buffer;
+		strbuf_reset(buf);
+		strbuf_addf(buf, "%.*s~%d", len, n->tip_name, n->generation);
+		return buf->buf;
 	}
 }
 
@@ -271,18 +335,20 @@ static void show_name(const struct object *obj,
 {
 	const char *name;
 	const struct object_id *oid = &obj->oid;
+	struct strbuf buf = STRBUF_INIT;
 
 	if (!name_only)
 		printf("%s ", caller_name ? caller_name : oid_to_hex(oid));
-	name = get_rev_name(obj);
+	name = get_rev_name(obj, &buf);
 	if (name)
 		printf("%s\n", name);
 	else if (allow_undefined)
 		printf("undefined\n");
 	else if (always)
-		printf("%s\n", find_unique_abbrev(oid->hash, DEFAULT_ABBREV));
+		printf("%s\n", find_unique_abbrev(oid, DEFAULT_ABBREV));
 	else
 		die("cannot describe '%s'", oid_to_hex(oid));
+	strbuf_release(&buf);
 }
 
 static char const * const name_rev_usage[] = {
@@ -294,15 +360,16 @@ static char const * const name_rev_usage[] = {
 
 static void name_rev_line(char *p, struct name_ref_data *data)
 {
+	struct strbuf buf = STRBUF_INIT;
 	int forty = 0;
 	char *p_start;
 	for (p_start = p; *p; p++) {
 #define ishex(x) (isdigit((x)) || ((x) >= 'a' && (x) <= 'f'))
 		if (!ishex(*p))
 			forty = 0;
-		else if (++forty == 40 &&
+		else if (++forty == GIT_SHA1_HEXSZ &&
 			 !ishex(*(p+1))) {
-			unsigned char sha1[40];
+			struct object_id oid;
 			const char *name = NULL;
 			char c = *(p+1);
 			int p_len = p - p_start + 1;
@@ -310,11 +377,12 @@ static void name_rev_line(char *p, struct name_ref_data *data)
 			forty = 0;
 
 			*(p+1) = 0;
-			if (!get_sha1(p - 39, sha1)) {
+			if (!get_oid(p - (GIT_SHA1_HEXSZ - 1), &oid)) {
 				struct object *o =
-					lookup_object(sha1);
+					lookup_object(the_repository,
+						      oid.hash);
 				if (o)
-					name = get_rev_name(o);
+					name = get_rev_name(o, &buf);
 			}
 			*(p+1) = c;
 
@@ -322,7 +390,7 @@ static void name_rev_line(char *p, struct name_ref_data *data)
 				continue;
 
 			if (data->name_only)
-				printf("%.*s%s", p_len - 40, p_start, name);
+				printf("%.*s%s", p_len - GIT_SHA1_HEXSZ, p_start, name);
 			else
 				printf("%.*s (%s)", p_len, p_start, name);
 			p_start = p + 1;
@@ -332,6 +400,8 @@ static void name_rev_line(char *p, struct name_ref_data *data)
 	/* flush */
 	if (p_start != p)
 		fwrite(p_start, p - p_start, 1, stdout);
+
+	strbuf_release(&buf);
 }
 
 int cmd_name_rev(int argc, const char **argv, const char *prefix)
@@ -361,6 +431,7 @@ int cmd_name_rev(int argc, const char **argv, const char *prefix)
 		OPT_END(),
 	};
 
+	init_commit_rev_name(&rev_names);
 	git_config(git_default_config, NULL);
 	argc = parse_options(argc, argv, prefix, opts, name_rev_usage, 0);
 	if (all + transform_stdin + !!argc > 1) {
@@ -371,20 +442,21 @@ int cmd_name_rev(int argc, const char **argv, const char *prefix)
 		cutoff = 0;
 
 	for (; argc; argc--, argv++) {
-		unsigned char sha1[20];
+		struct object_id oid;
 		struct object *object;
 		struct commit *commit;
 
-		if (get_sha1(*argv, sha1)) {
+		if (get_oid(*argv, &oid)) {
 			fprintf(stderr, "Could not get sha1 for %s. Skipping.\n",
 					*argv);
 			continue;
 		}
 
 		commit = NULL;
-		object = parse_object(sha1);
+		object = parse_object(the_repository, &oid);
 		if (object) {
-			struct object *peeled = deref_tag(object, *argv, 0);
+			struct object *peeled = deref_tag(the_repository,
+							  object, *argv, 0);
 			if (peeled && peeled->type == OBJ_COMMIT)
 				commit = (struct commit *)peeled;
 		}
@@ -442,5 +514,6 @@ int cmd_name_rev(int argc, const char **argv, const char *prefix)
 				  always, allow_undefined, data.name_only);
 	}
 
+	UNLEAK(revs);
 	return 0;
 }