[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"

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

static const char describe_usage[] =
"git-describe [--all] [--tags] [--abbrev=<n>] <committish>*";

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;

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;
		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 i;
	int contains = 0;

	for (i = 1; i < argc; i++) {
		const char *arg = argv[i];

		if (*arg != '-')
			break;
		else if (!strcmp(arg, "--contains"))
			contains = 1;
		else if (!strcmp(arg, "--debug"))
			debug = 1;
		else if (!strcmp(arg, "--all"))
			all = 1;
		else if (!strcmp(arg, "--tags"))
			tags = 1;
		else if (!prefixcmp(arg, "--abbrev=")) {
			abbrev = strtoul(arg + 9, NULL, 10);
			if (abbrev != 0 && (abbrev < MINIMUM_ABBREV || 40 < abbrev))
				abbrev = DEFAULT_ABBREV;
		}
		else if (!prefixcmp(arg, "--candidates=")) {
			max_candidates = strtoul(arg + 13, NULL, 10);
			if (max_candidates < 1)
				max_candidates = 1;
			else if (max_candidates > MAX_TAGS)
				max_candidates = MAX_TAGS;
		}
		else
			usage(describe_usage);
	}

	save_commit_buffer = 0;

	if (contains) {
		const char **args = xmalloc((4 + argc - i) * sizeof(char*));
		args[0] = "name-rev";
		args[1] = "--name-only";
		args[2] = "--tags";
		memcpy(args + 3, argv + i, (argc - i) * sizeof(char*));
		args[3 + argc - i] = NULL;
		return cmd_name_rev(3 + argc - i, args, prefix);
	}

	if (argc <= i)
		describe("HEAD", 1);
	else
		while (i < argc) {
			describe(argv[i], (i == argc - 1));
			i++;
		}

	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"
908e5310	7
8713ab30 SP	8	#define SEEN (1u<<0)
	9	#define MAX_TAGS (FLAG_BITS - 1)
	10
2d9e7c9f JH	11	static const char describe_usage[] =
2d9e7c9f JH	12	"git-describe [--all] [--tags] [--abbrev=<n>] <committish>*";
908e5310	13
8713ab30	14	static int debug; /* Display lots of verbose info */
96f1e58f DR	15	static int all; /* Default to annotated tags only */
96f1e58f DR	16	static int tags; /* But allow any tags if --tags is specified */
2d9e7c9f	17	static int abbrev = DEFAULT_ABBREV;
8713ab30	18	static int max_candidates = 10;
908e5310	19
e7eb5034	20	struct commit_name {
64deb858	21	int prio; /* annotated tag = 2, tag = 1, head = 0 */
5a2282de	22	char path[FLEX_ARRAY]; /* more */
e7eb5034	23	};
cf69fd49 SP	24	static const char *prio_names[] = {
	25	"head", "lightweight", "annotated",
	26	};
908e5310	27
64deb858	28	static void add_to_known_names(const char *path,
80dbae03	29	struct commit *commit,
64deb858	30	int prio)
908e5310	31	{
e7eb5034 SP	32	struct commit_name *e = commit->util;
	33	if (!e \|\| e->prio < prio) {
	34	size_t len = strlen(path)+1;
	35	free(e);
	36	e = xmalloc(sizeof(struct commit_name) + len);
	37	e->prio = prio;
	38	memcpy(e->path, path, len);
	39	commit->util = e;
908e5310	40	}
908e5310 LT	41	}
908e5310 LT	42
8da19775	43	static int get_name(const char path, const unsigned char sha1, int flag, void *cb_data)
908e5310 LT	44	{
908e5310 LT	45	struct commit *commit = lookup_commit_reference_gently(sha1, 1);
64deb858 JH	46	struct object *object;
	47	int prio;
	48
908e5310 LT	49	if (!commit)
908e5310 LT	50	return 0;
64deb858	51	object = parse_object(sha1);
2d9e7c9f JH	52	/* If --all, then any refs are used.
	53	* If --tags, then any tags are used.
	54	* Otherwise only annotated tags are used.
	55	*/
cc44c765	56	if (!prefixcmp(path, "refs/tags/")) {
1974632c	57	if (object->type == OBJ_TAG)
64deb858 JH	58	prio = 2;
	59	else
	60	prio = 1;
	61	}
	62	else
	63	prio = 0;
	64
635d4134	65	if (!all) {
64deb858 JH	66	if (!prio)
	67	return 0;
	68	if (!tags && prio < 2)
635d4134	69	return 0;
635d4134	70	}
64deb858	71	add_to_known_names(all ? path + 5 : path + 10, commit, prio);
908e5310 LT	72	return 0;
	73	}
	74
80dbae03	75	struct possible_tag {
80dbae03	76	struct commit_name *name;
cf69fd49 SP	77	int depth;
cf69fd49 SP	78	int found_order;
8713ab30	79	unsigned flag_within;
80dbae03 SP	80	};
80dbae03 SP	81
cf69fd49 SP	82	static int compare_pt(const void a_, const void b_)
	83	{
	84	struct possible_tag a = (struct possible_tag )a_;
	85	struct possible_tag b = (struct possible_tag )b_;
	86	if (a->name->prio != b->name->prio)
	87	return b->name->prio - a->name->prio;
	88	if (a->depth != b->depth)
	89	return a->depth - b->depth;
	90	if (a->found_order != b->found_order)
	91	return a->found_order - b->found_order;
	92	return 0;
	93	}
	94
1b600e65 SP	95	static unsigned long finish_depth_computation(
	96	struct commit_list **list,
	97	struct possible_tag *best)
	98	{
	99	unsigned long seen_commits = 0;
	100	while (*list) {
	101	struct commit *c = pop_commit(list);
	102	struct commit_list *parents = c->parents;
	103	seen_commits++;
	104	if (c->object.flags & best->flag_within) {
	105	struct commit_list a = list;
	106	while (a) {
	107	struct commit *i = a->item;
	108	if (!(i->object.flags & best->flag_within))
	109	break;
	110	a = a->next;
	111	}
	112	if (!a)
	113	break;
	114	} else
	115	best->depth++;
	116	while (parents) {
	117	struct commit *p = parents->item;
	118	parse_commit(p);
	119	if (!(p->object.flags & SEEN))
	120	insert_by_date(p, list);
	121	p->object.flags \|= c->object.flags;
	122	parents = parents->next;
	123	}
	124	}
	125	return seen_commits;
	126	}
	127
554fe20d	128	static void describe(const char *arg, int last_one)
908e5310	129	{
4c34a2c5	130	unsigned char sha1[20];
8713ab30	131	struct commit cmit, gave_up_on = NULL;
908e5310 LT	132	struct commit_list *list;
	133	static int initialized = 0;
	134	struct commit_name *n;
cf69fd49	135	struct possible_tag all_matches[MAX_TAGS];
8713ab30 SP	136	unsigned int match_cnt = 0, annotated_cnt = 0, cur_match;
8713ab30 SP	137	unsigned long seen_commits = 0;
908e5310	138
31fff305 DL	139	if (get_sha1(arg, sha1))
31fff305 DL	140	die("Not a valid object name %s", arg);
4c34a2c5 JH	141	cmit = lookup_commit_reference(sha1);
4c34a2c5 JH	142	if (!cmit)
31fff305	143	die("%s is not a valid '%s' object", arg, commit_type);
4c34a2c5	144
908e5310 LT	145	if (!initialized) {
908e5310 LT	146	initialized = 1;
cb5d709f	147	for_each_ref(get_name, NULL);
908e5310 LT	148	}
908e5310 LT	149
e7eb5034	150	n = cmit->util;
908e5310 LT	151	if (n) {
	152	printf("%s\n", n->path);
	153	return;
	154	}
	155
8713ab30 SP	156	if (debug)
	157	fprintf(stderr, "searching to describe %s\n", arg);
	158
908e5310	159	list = NULL;
8713ab30	160	cmit->object.flags = SEEN;
908e5310 LT	161	commit_list_insert(cmit, &list);
908e5310 LT	162	while (list) {
80dbae03	163	struct commit *c = pop_commit(&list);
dccd0c2a	164	struct commit_list *parents = c->parents;
8713ab30	165	seen_commits++;
e7eb5034	166	n = c->util;
908e5310	167	if (n) {
8713ab30 SP	168	if (match_cnt < max_candidates) {
	169	struct possible_tag *t = &all_matches[match_cnt++];
	170	t->name = n;
	171	t->depth = seen_commits - 1;
	172	t->flag_within = 1u << match_cnt;
8a8169c0	173	t->found_order = match_cnt;
8713ab30 SP	174	c->object.flags \|= t->flag_within;
	175	if (n->prio == 2)
	176	annotated_cnt++;
	177	}
	178	else {
	179	gave_up_on = c;
	180	break;
	181	}
	182	}
	183	for (cur_match = 0; cur_match < match_cnt; cur_match++) {
	184	struct possible_tag *t = &all_matches[cur_match];
	185	if (!(c->object.flags & t->flag_within))
	186	t->depth++;
	187	}
	188	if (annotated_cnt && !list) {
	189	if (debug)
	190	fprintf(stderr, "finished search at %s\n",
	191	sha1_to_hex(c->object.sha1));
	192	break;
dccd0c2a SP	193	}
	194	while (parents) {
	195	struct commit *p = parents->item;
	196	parse_commit(p);
8713ab30	197	if (!(p->object.flags & SEEN))
dccd0c2a	198	insert_by_date(p, &list);
8713ab30	199	p->object.flags \|= c->object.flags;
dccd0c2a	200	parents = parents->next;
80dbae03 SP	201	}
	202	}
	203
8713ab30	204	if (!match_cnt)
80dbae03 SP	205	die("cannot describe '%s'", sha1_to_hex(cmit->object.sha1));
80dbae03 SP	206
cf69fd49	207	qsort(all_matches, match_cnt, sizeof(all_matches[0]), compare_pt);
1b600e65 SP	208
	209	if (gave_up_on) {
	210	insert_by_date(gave_up_on, &list);
	211	seen_commits--;
	212	}
	213	seen_commits += finish_depth_computation(&list, &all_matches[0]);
	214	free_commit_list(list);
	215
8713ab30 SP	216	if (debug) {
	217	for (cur_match = 0; cur_match < match_cnt; cur_match++) {
	218	struct possible_tag *t = &all_matches[cur_match];
cf69fd49 SP	219	fprintf(stderr, " %-11s %8d %s\n",
cf69fd49 SP	220	prio_names[t->name->prio],
8713ab30 SP	221	t->depth, t->name->path);
	222	}
	223	fprintf(stderr, "traversed %lu commits\n", seen_commits);
	224	if (gave_up_on) {
	225	fprintf(stderr,
	226	"more than %i tags found; listed %i most recent\n"
	227	"gave up search at %s\n",
	228	max_candidates, max_candidates,
	229	sha1_to_hex(gave_up_on->object.sha1));
	230	}
80dbae03	231	}
f127404c AP	232	if (abbrev == 0)
	233	printf("%s\n", all_matches[0].name->path );
	234	else
237fb6ca SP	235	printf("%s-%d-g%s\n", all_matches[0].name->path,
	236	all_matches[0].depth,
	237	find_unique_abbrev(cmit->object.sha1, abbrev));
80dbae03	238
8713ab30 SP	239	if (!last_one)
8713ab30 SP	240	clear_commit_marks(cmit, -1);
908e5310 LT	241	}
908e5310 LT	242
9a0eaf83	243	int cmd_describe(int argc, const char *argv, const char prefix)
908e5310 LT	244	{
908e5310 LT	245	int i;
23615708	246	int contains = 0;
908e5310 LT	247
	248	for (i = 1; i < argc; i++) {
	249	const char *arg = argv[i];
908e5310	250
4c34a2c5 JH	251	if (*arg != '-')
4c34a2c5 JH	252	break;
23615708 SP	253	else if (!strcmp(arg, "--contains"))
23615708 SP	254	contains = 1;
8713ab30 SP	255	else if (!strcmp(arg, "--debug"))
8713ab30 SP	256	debug = 1;
4c34a2c5	257	else if (!strcmp(arg, "--all"))
908e5310	258	all = 1;
4c34a2c5	259	else if (!strcmp(arg, "--tags"))
2d9e7c9f	260	tags = 1;
cc44c765	261	else if (!prefixcmp(arg, "--abbrev=")) {
2d9e7c9f	262	abbrev = strtoul(arg + 9, NULL, 10);
f127404c	263	if (abbrev != 0 && (abbrev < MINIMUM_ABBREV \|\| 40 < abbrev))
2d9e7c9f	264	abbrev = DEFAULT_ABBREV;
2d9e7c9f	265	}
cc44c765	266	else if (!prefixcmp(arg, "--candidates=")) {
8713ab30 SP	267	max_candidates = strtoul(arg + 13, NULL, 10);
	268	if (max_candidates < 1)
	269	max_candidates = 1;
	270	else if (max_candidates > MAX_TAGS)
	271	max_candidates = MAX_TAGS;
	272	}
4c34a2c5	273	else
908e5310	274	usage(describe_usage);
908e5310	275	}
4c34a2c5	276
8c599c74	277	save_commit_buffer = 0;
8112894d	278
23615708 SP	279	if (contains) {
	280	const char *args = xmalloc((4 + argc - i) sizeof(char*));
	281	args[0] = "name-rev";
	282	args[1] = "--name-only";
	283	args[2] = "--tags";
	284	memcpy(args + 3, argv + i, (argc - i) * sizeof(char*));
	285	args[3 + argc - i] = NULL;
	286	return cmd_name_rev(3 + argc - i, args, prefix);
	287	}
	288
5b6df8e4	289	if (argc <= i)
fec9ebf1	290	describe("HEAD", 1);
4c34a2c5	291	else
fec9ebf1 JH	292	while (i < argc) {
	293	describe(argv[i], (i == argc - 1));
	294	i++;
	295	}
4c34a2c5	296
908e5310 LT	297	return 0;
908e5310 LT	298	}