[thirdparty/git.git] / builtin-describe.c

#include "cache.h"
#include "commit.h"
#include "tag.h"
#include "refs.h"
#include "builtin.h"
#include "exec_cmd.h"
#include "parse-options.h"

#define SEEN		(1u<<0)
#define MAX_TAGS	(FLAG_BITS - 1)

static const char * const describe_usage[] = {
	"git-describe [options] <committish>*",
	NULL
};

static int debug;	/* Display lots of verbose info */
static int all;	/* Default to annotated tags only */
static int tags;	/* But allow any tags if --tags is specified */
static int abbrev = DEFAULT_ABBREV;
static int max_candidates = 10;
const char *pattern = NULL;

struct commit_name {
	int prio; /* annotated tag = 2, tag = 1, head = 0 */
	char path[FLEX_ARRAY]; /* more */
};
static const char *prio_names[] = {
	"head", "lightweight", "annotated",
};

static void add_to_known_names(const char *path,
			       struct commit *commit,
			       int prio)
{
	struct commit_name *e = commit->util;
	if (!e || e->prio < prio) {
		size_t len = strlen(path)+1;
		free(e);
		e = xmalloc(sizeof(struct commit_name) + len);
		e->prio = prio;
		memcpy(e->path, path, len);
		commit->util = e;
	}
}

static int get_name(const char *path, const unsigned char *sha1, int flag, void *cb_data)
{
	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 (!prefixcmp(path, "refs/tags/")) {
		if (object->type == OBJ_TAG) {
			prio = 2;
			if (pattern && fnmatch(pattern, path + 10, 0))
				prio = 0;
		} else
			prio = 1;
	}
	else
		prio = 0;

	if (!all) {
		if (!prio)
			return 0;
		if (!tags && prio < 2)
			return 0;
	}
	add_to_known_names(all ? path + 5 : path + 10, commit, prio);
	return 0;
}

struct possible_tag {
	struct commit_name *name;
	int depth;
	int found_order;
	unsigned flag_within;
};

static int compare_pt(const void *a_, const void *b_)
{
	struct possible_tag *a = (struct possible_tag *)a_;
	struct possible_tag *b = (struct possible_tag *)b_;
	if (a->name->prio != b->name->prio)
		return b->name->prio - a->name->prio;
	if (a->depth != b->depth)
		return a->depth - b->depth;
	if (a->found_order != b->found_order)
		return a->found_order - b->found_order;
	return 0;
}

static unsigned long finish_depth_computation(
	struct commit_list **list,
	struct possible_tag *best)
{
	unsigned long seen_commits = 0;
	while (*list) {
		struct commit *c = pop_commit(list);
		struct commit_list *parents = c->parents;
		seen_commits++;
		if (c->object.flags & best->flag_within) {
			struct commit_list *a = *list;
			while (a) {
				struct commit *i = a->item;
				if (!(i->object.flags & best->flag_within))
					break;
				a = a->next;
			}
			if (!a)
				break;
		} else
			best->depth++;
		while (parents) {
			struct commit *p = parents->item;
			parse_commit(p);
			if (!(p->object.flags & SEEN))
				insert_by_date(p, list);
			p->object.flags |= c->object.flags;
			parents = parents->next;
		}
	}
	return seen_commits;
}

static void describe(const char *arg, int last_one)
{
	unsigned char sha1[20];
	struct commit *cmit, *gave_up_on = NULL;
	struct commit_list *list;
	static int initialized = 0;
	struct commit_name *n;
	struct possible_tag all_matches[MAX_TAGS];
	unsigned int match_cnt = 0, annotated_cnt = 0, cur_match;
	unsigned long seen_commits = 0;

	if (get_sha1(arg, sha1))
		die("Not a valid object name %s", arg);
	cmit = lookup_commit_reference(sha1);
	if (!cmit)
		die("%s is not a valid '%s' object", arg, commit_type);

	if (!initialized) {
		initialized = 1;
		for_each_ref(get_name, NULL);
	}

	n = cmit->util;
	if (n) {
		printf("%s\n", n->path);
		return;
	}

	if (debug)
		fprintf(stderr, "searching to describe %s\n", arg);

	list = NULL;
	cmit->object.flags = SEEN;
	commit_list_insert(cmit, &list);
	while (list) {
		struct commit *c = pop_commit(&list);
		struct commit_list *parents = c->parents;
		seen_commits++;
		n = c->util;
		if (n) {
			if (match_cnt < max_candidates) {
				struct possible_tag *t = &all_matches[match_cnt++];
				t->name = n;
				t->depth = seen_commits - 1;
				t->flag_within = 1u << match_cnt;
				t->found_order = match_cnt;
				c->object.flags |= t->flag_within;
				if (n->prio == 2)
					annotated_cnt++;
			}
			else {
				gave_up_on = c;
				break;
			}
		}
		for (cur_match = 0; cur_match < match_cnt; cur_match++) {
			struct possible_tag *t = &all_matches[cur_match];
			if (!(c->object.flags & t->flag_within))
				t->depth++;
		}
		if (annotated_cnt && !list) {
			if (debug)
				fprintf(stderr, "finished search at %s\n",
					sha1_to_hex(c->object.sha1));
			break;
		}
		while (parents) {
			struct commit *p = parents->item;
			parse_commit(p);
			if (!(p->object.flags & SEEN))
				insert_by_date(p, &list);
			p->object.flags |= c->object.flags;
			parents = parents->next;
		}
	}

	if (!match_cnt)
		die("cannot describe '%s'", sha1_to_hex(cmit->object.sha1));

	qsort(all_matches, match_cnt, sizeof(all_matches[0]), compare_pt);

	if (gave_up_on) {
		insert_by_date(gave_up_on, &list);
		seen_commits--;
	}
	seen_commits += finish_depth_computation(&list, &all_matches[0]);
	free_commit_list(list);

	if (debug) {
		for (cur_match = 0; cur_match < match_cnt; cur_match++) {
			struct possible_tag *t = &all_matches[cur_match];
			fprintf(stderr, " %-11s %8d %s\n",
				prio_names[t->name->prio],
				t->depth, t->name->path);
		}
		fprintf(stderr, "traversed %lu commits\n", seen_commits);
		if (gave_up_on) {
			fprintf(stderr,
				"more than %i tags found; listed %i most recent\n"
				"gave up search at %s\n",
				max_candidates, max_candidates,
				sha1_to_hex(gave_up_on->object.sha1));
		}
	}
	if (abbrev == 0)
		printf("%s\n", all_matches[0].name->path );
	else
		printf("%s-%d-g%s\n", all_matches[0].name->path,
		       all_matches[0].depth,
		       find_unique_abbrev(cmit->object.sha1, abbrev));

	if (!last_one)
		clear_commit_marks(cmit, -1);
}

int cmd_describe(int argc, const char **argv, const char *prefix)
{
	int contains = 0;
	struct option options[] = {
		OPT_BOOLEAN(0, "contains",   &contains, "find the tag that comes after the commit"),
		OPT_BOOLEAN(0, "debug",      &debug, "debug search strategy on stderr"),
		OPT_BOOLEAN(0, "all",        &all, "use any ref in .git/refs"),
		OPT_BOOLEAN(0, "tags",       &tags, "use any tag in .git/refs/tags"),
		OPT__ABBREV(&abbrev),
		OPT_INTEGER(0, "candidates", &max_candidates,
			    "consider <n> most recent tags (default: 10)"),
		OPT_STRING(0, "match",       &pattern, "pattern",
			   "only consider tags matching <pattern>"),
		OPT_END(),
	};

	argc = parse_options(argc, argv, options, describe_usage, 0);
	if (max_candidates < 1)
		max_candidates = 1;
	else if (max_candidates > MAX_TAGS)
		max_candidates = MAX_TAGS;

	save_commit_buffer = 0;

	if (contains) {
		const char **args = xmalloc((6 + argc) * sizeof(char*));
		int i = 0;
		args[i++] = "name-rev";
		args[i++] = "--name-only";
		args[i++] = "--no-undefined";
		if (!all) {
			args[i++] = "--tags";
			if (pattern) {
				char *s = xmalloc(strlen("--refs=refs/tags/") + strlen(pattern) + 1);
				sprintf(s, "--refs=refs/tags/%s", pattern);
				args[i++] = s;
			}
		}
		memcpy(args + i, argv, argc * sizeof(char*));
		args[i + argc] = NULL;
		return cmd_name_rev(i + argc, args, prefix);
	}

	if (argc == 0) {
		describe("HEAD", 1);
	} else {
		while (argc-- > 0) {
			describe(*argv++, argc == 0);
		}
	}
	return 0;
}
Commit	Line	Data
908e5310 LT	1	#include "cache.h"
908e5310 LT	2	#include "commit.h"
635d4134	3	#include "tag.h"
908e5310	4	#include "refs.h"
9a0eaf83	5	#include "builtin.h"
23615708	6	#include "exec_cmd.h"
166185be	7	#include "parse-options.h"
908e5310	8
8713ab30 SP	9	#define SEEN (1u<<0)
	10	#define MAX_TAGS (FLAG_BITS - 1)
	11
166185be PH	12	static const char * const describe_usage[] = {
	13	"git-describe [options] <committish>*",
	14	NULL
	15	};
908e5310	16
8713ab30	17	static int debug; /* Display lots of verbose info */
96f1e58f DR	18	static int all; /* Default to annotated tags only */
96f1e58f DR	19	static int tags; /* But allow any tags if --tags is specified */
2d9e7c9f	20	static int abbrev = DEFAULT_ABBREV;
8713ab30	21	static int max_candidates = 10;
30ffa603	22	const char *pattern = NULL;
908e5310	23
e7eb5034	24	struct commit_name {
64deb858	25	int prio; /* annotated tag = 2, tag = 1, head = 0 */
5a2282de	26	char path[FLEX_ARRAY]; /* more */
e7eb5034	27	};
cf69fd49 SP	28	static const char *prio_names[] = {
	29	"head", "lightweight", "annotated",
	30	};
908e5310	31
64deb858	32	static void add_to_known_names(const char *path,
80dbae03	33	struct commit *commit,
64deb858	34	int prio)
908e5310	35	{
e7eb5034 SP	36	struct commit_name *e = commit->util;
	37	if (!e \|\| e->prio < prio) {
	38	size_t len = strlen(path)+1;
	39	free(e);
	40	e = xmalloc(sizeof(struct commit_name) + len);
	41	e->prio = prio;
	42	memcpy(e->path, path, len);
	43	commit->util = e;
908e5310	44	}
908e5310 LT	45	}
908e5310 LT	46
8da19775	47	static int get_name(const char path, const unsigned char sha1, int flag, void *cb_data)
908e5310 LT	48	{
908e5310 LT	49	struct commit *commit = lookup_commit_reference_gently(sha1, 1);
64deb858 JH	50	struct object *object;
	51	int prio;
	52
908e5310 LT	53	if (!commit)
908e5310 LT	54	return 0;
64deb858	55	object = parse_object(sha1);
2d9e7c9f JH	56	/* If --all, then any refs are used.
	57	* If --tags, then any tags are used.
	58	* Otherwise only annotated tags are used.
	59	*/
cc44c765	60	if (!prefixcmp(path, "refs/tags/")) {
30ffa603	61	if (object->type == OBJ_TAG) {
64deb858	62	prio = 2;
30ffa603 PH	63	if (pattern && fnmatch(pattern, path + 10, 0))
	64	prio = 0;
	65	} else
64deb858 JH	66	prio = 1;
	67	}
	68	else
	69	prio = 0;
	70
635d4134	71	if (!all) {
64deb858 JH	72	if (!prio)
	73	return 0;
	74	if (!tags && prio < 2)
635d4134	75	return 0;
635d4134	76	}
64deb858	77	add_to_known_names(all ? path + 5 : path + 10, commit, prio);
908e5310 LT	78	return 0;
	79	}
	80
80dbae03	81	struct possible_tag {
80dbae03	82	struct commit_name *name;
cf69fd49 SP	83	int depth;
cf69fd49 SP	84	int found_order;
8713ab30	85	unsigned flag_within;
80dbae03 SP	86	};
80dbae03 SP	87
cf69fd49 SP	88	static int compare_pt(const void a_, const void b_)
	89	{
	90	struct possible_tag a = (struct possible_tag )a_;
	91	struct possible_tag b = (struct possible_tag )b_;
	92	if (a->name->prio != b->name->prio)
	93	return b->name->prio - a->name->prio;
	94	if (a->depth != b->depth)
	95	return a->depth - b->depth;
	96	if (a->found_order != b->found_order)
	97	return a->found_order - b->found_order;
	98	return 0;
	99	}
	100
1b600e65 SP	101	static unsigned long finish_depth_computation(
	102	struct commit_list **list,
	103	struct possible_tag *best)
	104	{
	105	unsigned long seen_commits = 0;
	106	while (*list) {
	107	struct commit *c = pop_commit(list);
	108	struct commit_list *parents = c->parents;
	109	seen_commits++;
	110	if (c->object.flags & best->flag_within) {
	111	struct commit_list a = list;
	112	while (a) {
	113	struct commit *i = a->item;
	114	if (!(i->object.flags & best->flag_within))
	115	break;
	116	a = a->next;
	117	}
	118	if (!a)
	119	break;
	120	} else
	121	best->depth++;
	122	while (parents) {
	123	struct commit *p = parents->item;
	124	parse_commit(p);
	125	if (!(p->object.flags & SEEN))
	126	insert_by_date(p, list);
	127	p->object.flags \|= c->object.flags;
	128	parents = parents->next;
	129	}
	130	}
	131	return seen_commits;
	132	}
	133
554fe20d	134	static void describe(const char *arg, int last_one)
908e5310	135	{
4c34a2c5	136	unsigned char sha1[20];
8713ab30	137	struct commit cmit, gave_up_on = NULL;
908e5310 LT	138	struct commit_list *list;
	139	static int initialized = 0;
	140	struct commit_name *n;
cf69fd49	141	struct possible_tag all_matches[MAX_TAGS];
8713ab30 SP	142	unsigned int match_cnt = 0, annotated_cnt = 0, cur_match;
8713ab30 SP	143	unsigned long seen_commits = 0;
908e5310	144
31fff305 DL	145	if (get_sha1(arg, sha1))
31fff305 DL	146	die("Not a valid object name %s", arg);
4c34a2c5 JH	147	cmit = lookup_commit_reference(sha1);
4c34a2c5 JH	148	if (!cmit)
31fff305	149	die("%s is not a valid '%s' object", arg, commit_type);
4c34a2c5	150
908e5310 LT	151	if (!initialized) {
908e5310 LT	152	initialized = 1;
cb5d709f	153	for_each_ref(get_name, NULL);
908e5310 LT	154	}
908e5310 LT	155
e7eb5034	156	n = cmit->util;
908e5310 LT	157	if (n) {
	158	printf("%s\n", n->path);
	159	return;
	160	}
	161
8713ab30 SP	162	if (debug)
	163	fprintf(stderr, "searching to describe %s\n", arg);
	164
908e5310	165	list = NULL;
8713ab30	166	cmit->object.flags = SEEN;
908e5310 LT	167	commit_list_insert(cmit, &list);
908e5310 LT	168	while (list) {
80dbae03	169	struct commit *c = pop_commit(&list);
dccd0c2a	170	struct commit_list *parents = c->parents;
8713ab30	171	seen_commits++;
e7eb5034	172	n = c->util;
908e5310	173	if (n) {
8713ab30 SP	174	if (match_cnt < max_candidates) {
	175	struct possible_tag *t = &all_matches[match_cnt++];
	176	t->name = n;
	177	t->depth = seen_commits - 1;
	178	t->flag_within = 1u << match_cnt;
8a8169c0	179	t->found_order = match_cnt;
8713ab30 SP	180	c->object.flags \|= t->flag_within;
	181	if (n->prio == 2)
	182	annotated_cnt++;
	183	}
	184	else {
	185	gave_up_on = c;
	186	break;
	187	}
	188	}
	189	for (cur_match = 0; cur_match < match_cnt; cur_match++) {
	190	struct possible_tag *t = &all_matches[cur_match];
	191	if (!(c->object.flags & t->flag_within))
	192	t->depth++;
	193	}
	194	if (annotated_cnt && !list) {
	195	if (debug)
	196	fprintf(stderr, "finished search at %s\n",
	197	sha1_to_hex(c->object.sha1));
	198	break;
dccd0c2a SP	199	}
	200	while (parents) {
	201	struct commit *p = parents->item;
	202	parse_commit(p);
8713ab30	203	if (!(p->object.flags & SEEN))
dccd0c2a	204	insert_by_date(p, &list);
8713ab30	205	p->object.flags \|= c->object.flags;
dccd0c2a	206	parents = parents->next;
80dbae03 SP	207	}
	208	}
	209
8713ab30	210	if (!match_cnt)
80dbae03 SP	211	die("cannot describe '%s'", sha1_to_hex(cmit->object.sha1));
80dbae03 SP	212
cf69fd49	213	qsort(all_matches, match_cnt, sizeof(all_matches[0]), compare_pt);
1b600e65 SP	214
	215	if (gave_up_on) {
	216	insert_by_date(gave_up_on, &list);
	217	seen_commits--;
	218	}
	219	seen_commits += finish_depth_computation(&list, &all_matches[0]);
	220	free_commit_list(list);
	221
8713ab30 SP	222	if (debug) {
	223	for (cur_match = 0; cur_match < match_cnt; cur_match++) {
	224	struct possible_tag *t = &all_matches[cur_match];
cf69fd49 SP	225	fprintf(stderr, " %-11s %8d %s\n",
cf69fd49 SP	226	prio_names[t->name->prio],
8713ab30 SP	227	t->depth, t->name->path);
	228	}
	229	fprintf(stderr, "traversed %lu commits\n", seen_commits);
	230	if (gave_up_on) {
	231	fprintf(stderr,
	232	"more than %i tags found; listed %i most recent\n"
	233	"gave up search at %s\n",
	234	max_candidates, max_candidates,
	235	sha1_to_hex(gave_up_on->object.sha1));
	236	}
80dbae03	237	}
f127404c AP	238	if (abbrev == 0)
	239	printf("%s\n", all_matches[0].name->path );
	240	else
237fb6ca SP	241	printf("%s-%d-g%s\n", all_matches[0].name->path,
	242	all_matches[0].depth,
	243	find_unique_abbrev(cmit->object.sha1, abbrev));
80dbae03	244
8713ab30 SP	245	if (!last_one)
8713ab30 SP	246	clear_commit_marks(cmit, -1);
908e5310 LT	247	}
908e5310 LT	248
9a0eaf83	249	int cmd_describe(int argc, const char *argv, const char prefix)
908e5310	250	{
23615708	251	int contains = 0;
166185be PH	252	struct option options[] = {
	253	OPT_BOOLEAN(0, "contains", &contains, "find the tag that comes after the commit"),
	254	OPT_BOOLEAN(0, "debug", &debug, "debug search strategy on stderr"),
	255	OPT_BOOLEAN(0, "all", &all, "use any ref in .git/refs"),
	256	OPT_BOOLEAN(0, "tags", &tags, "use any tag in .git/refs/tags"),
	257	OPT__ABBREV(&abbrev),
	258	OPT_INTEGER(0, "candidates", &max_candidates,
30ffa603 PH	259	"consider <n> most recent tags (default: 10)"),
	260	OPT_STRING(0, "match", &pattern, "pattern",
	261	"only consider tags matching <pattern>"),
166185be PH	262	OPT_END(),
166185be PH	263	};
908e5310	264
166185be PH	265	argc = parse_options(argc, argv, options, describe_usage, 0);
	266	if (max_candidates < 1)
	267	max_candidates = 1;
	268	else if (max_candidates > MAX_TAGS)
	269	max_candidates = MAX_TAGS;
4c34a2c5	270
8c599c74	271	save_commit_buffer = 0;
8112894d	272
23615708	273	if (contains) {
a2cf9f44	274	const char *args = xmalloc((6 + argc) sizeof(char*));
3f7701a4 NP	275	int i = 0;
	276	args[i++] = "name-rev";
	277	args[i++] = "--name-only";
a2cf9f44	278	args[i++] = "--no-undefined";
30ffa603	279	if (!all) {
3f7701a4	280	args[i++] = "--tags";
30ffa603 PH	281	if (pattern) {
	282	char *s = xmalloc(strlen("--refs=refs/tags/") + strlen(pattern) + 1);
	283	sprintf(s, "--refs=refs/tags/%s", pattern);
	284	args[i++] = s;
	285	}
	286	}
3f7701a4 NP	287	memcpy(args + i, argv, argc * sizeof(char*));
	288	args[i + argc] = NULL;
	289	return cmd_name_rev(i + argc, args, prefix);
23615708 SP	290	}
23615708 SP	291
166185be	292	if (argc == 0) {
fec9ebf1	293	describe("HEAD", 1);
166185be PH	294	} else {
	295	while (argc-- > 0) {
	296	describe(*argv++, argc == 0);
fec9ebf1	297	}
166185be	298	}
908e5310 LT	299	return 0;
908e5310 LT	300	}