[thirdparty/git.git] / show-branch.c

#include <stdlib.h>
#include "cache.h"
#include "commit.h"
#include "refs.h"

static const char show_branch_usage[] =
"git-show-branch [--all] [--heads] [--tags] [--more=count | --list | --independent | --merge-base ] [<refs>...]";

#define UNINTERESTING	01

#define REV_SHIFT	 2
#define MAX_REVS	29 /* should not exceed bits_per_int - REV_SHIFT */

static struct commit *interesting(struct commit_list *list)
{
	while (list) {
		struct commit *commit = list->item;
		list = list->next;
		if (commit->object.flags & UNINTERESTING)
			continue;
		return commit;
	}
	return NULL;
}

static struct commit *pop_one_commit(struct commit_list **list_p)
{
	struct commit *commit;
	struct commit_list *list;
	list = *list_p;
	commit = list->item;
	*list_p = list->next;
	free(list);
	return commit;
}

struct commit_name {
	const char *head_name; /* which head's ancestor? */
	int generation; /* how many parents away from head_name */
};

/* Name the commit as nth generation ancestor of head_name;
 * we count only the first-parent relationship for naming purposes.
 */
static void name_commit(struct commit *commit, const char *head_name, int nth)
{
	struct commit_name *name;
	if (!commit->object.util)
		commit->object.util = xmalloc(sizeof(struct commit_name));
	name = commit->object.util;
	name->head_name = head_name;
	name->generation = nth;
}

/* Parent is the first parent of the commit.  We may name it
 * as (n+1)th generation ancestor of the same head_name as
 * commit is nth generation ancestore of, if that generation
 * number is better than the name it already has.
 */
static void name_parent(struct commit *commit, struct commit *parent)
{
	struct commit_name *commit_name = commit->object.util;
	struct commit_name *parent_name = parent->object.util;
	if (!commit_name)
		return;
	if (!parent_name ||
	    commit_name->generation + 1 < parent_name->generation)
		name_commit(parent, commit_name->head_name,
			    commit_name->generation + 1);
}

static int name_first_parent_chain(struct commit *c)
{
	int i = 0;
	while (c) {
		struct commit *p;
		if (!c->object.util)
			break;
		if (!c->parents)
			break;
		p = c->parents->item;
		if (!p->object.util) {
			name_parent(c, p);
			i++;
		}
		c = p;
	}
	return i;
}

static void name_commits(struct commit_list *list,
			 struct commit **rev,
			 char **ref_name,
			 int num_rev)
{
	struct commit_list *cl;
	struct commit *c;
	int i;

	/* First give names to the given heads */
	for (cl = list; cl; cl = cl->next) {
		c = cl->item;
		if (c->object.util)
			continue;
		for (i = 0; i < num_rev; i++) {
			if (rev[i] == c) {
				name_commit(c, ref_name[i], 0);
				break;
			}
		}
	}

	/* Then commits on the first parent ancestry chain */
	do {
		i = 0;
		for (cl = list; cl; cl = cl->next) {
			i += name_first_parent_chain(cl->item);
		}
	} while (i);

	/* Finally, any unnamed commits */
	do {
		i = 0;
		for (cl = list; cl; cl = cl->next) {
			struct commit_list *parents;
			struct commit_name *n;
			int nth;
			c = cl->item;
			if (!c->object.util)
				continue;
			n = c->object.util;
			parents = c->parents;
			nth = 0;
			while (parents) {
				struct commit *p = parents->item;
				char newname[1000], *en;
				parents = parents->next;
				nth++;
				if (p->object.util)
					continue;
				en = newname;
				switch (n->generation) {
				case 0:
					en += sprintf(en, "%s", n->head_name);
					break;
				case 1:
					en += sprintf(en, "%s^", n->head_name);
					break;
				default:
					en += sprintf(en, "%s~%d",
						n->head_name, n->generation);
					break;
				}
				if (nth == 1)
					en += sprintf(en, "^");
				else
					en += sprintf(en, "^%d", nth);
				name_commit(p, strdup(newname), 0);
				i++;
				name_first_parent_chain(p);
			}
		}
	} while (i);
}

static int mark_seen(struct commit *commit, struct commit_list **seen_p)
{
	if (!commit->object.flags) {
		insert_by_date(commit, seen_p);
		return 1;
	}
	return 0;
}

static void join_revs(struct commit_list **list_p,
		      struct commit_list **seen_p,
		      int num_rev, int extra)
{
	int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
	int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);

	while (*list_p) {
		struct commit_list *parents;
		int still_interesting = !!interesting(*list_p);
		struct commit *commit = pop_one_commit(list_p);
		int flags = commit->object.flags & all_mask;

		if (!still_interesting && extra <= 0)
			break;

		mark_seen(commit, seen_p);
		if ((flags & all_revs) == all_revs)
			flags |= UNINTERESTING;
		parents = commit->parents;

		while (parents) {
			struct commit *p = parents->item;
			int this_flag = p->object.flags;
			parents = parents->next;
			if ((this_flag & flags) == flags)
				continue;
			if (!p->object.parsed)
				parse_commit(p);
			if (mark_seen(p, seen_p) && !still_interesting)
				extra--;
			p->object.flags |= flags;
			insert_by_date(p, list_p);
		}
	}

	/*
	 * Postprocess to complete well-poisoning.
	 *
	 * At this point we have all the commits we have seen in
	 * seen_p list (which happens to be sorted chronologically but
	 * it does not really matter).  Mark anything that can be
	 * reached from uninteresting commits not interesting.
	 */
	for (;;) {
		int changed = 0;
		struct commit_list *s;
		for (s = *seen_p; s; s = s->next) {
			struct commit *c = s->item;
			struct commit_list *parents;

			if (((c->object.flags & all_revs) != all_revs) &&
			    !(c->object.flags & UNINTERESTING))
				continue;

			/* The current commit is either a merge base or
			 * already uninteresting one.  Mark its parents
			 * as uninteresting commits _only_ if they are
			 * already parsed.  No reason to find new ones
			 * here.
			 */
			parents = c->parents;
			while (parents) {
				struct commit *p = parents->item;
				parents = parents->next;
				if (!(p->object.flags & UNINTERESTING)) {
					p->object.flags |= UNINTERESTING;
					changed = 1;
				}
			}
		}
		if (!changed)
			break;
	}
}

static void show_one_commit(struct commit *commit, int no_name)
{
	char pretty[256], *cp;
	struct commit_name *name = commit->object.util;
	if (commit->object.parsed)
		pretty_print_commit(CMIT_FMT_ONELINE, commit->buffer, ~0,
				    pretty, sizeof(pretty));
	else
		strcpy(pretty, "(unavailable)");
	if (!strncmp(pretty, "[PATCH] ", 8))
		cp = pretty + 8;
	else
		cp = pretty;

	if (!no_name) {
		if (name && name->head_name) {
			printf("[%s", name->head_name);
			if (name->generation) {
				if (name->generation == 1)
					printf("^");
				else
					printf("~%d", name->generation);
			}
			printf("] ");
		}
		else
			printf("[%s] ",
			       find_unique_abbrev(commit->object.sha1, 7));
	}
	puts(cp);
}

static char *ref_name[MAX_REVS + 1];
static int ref_name_cnt;

static int compare_ref_name(const void *a_, const void *b_)
{
	const char * const*a = a_, * const*b = b_;
	return strcmp(*a, *b);
}

static void sort_ref_range(int bottom, int top)
{
	qsort(ref_name + bottom, top - bottom, sizeof(ref_name[0]),
	      compare_ref_name);
}

static int append_ref(const char *refname, const unsigned char *sha1)
{
	struct commit *commit = lookup_commit_reference_gently(sha1, 1);
	if (!commit)
		return 0;
	if (MAX_REVS <= ref_name_cnt) {
		fprintf(stderr, "warning: ignoring %s; "
			"cannot handle more than %d refs",
			refname, MAX_REVS);
		return 0;
	}
	ref_name[ref_name_cnt++] = strdup(refname);
	ref_name[ref_name_cnt] = NULL;
	return 0;
}

static int append_head_ref(const char *refname, const unsigned char *sha1)
{
	unsigned char tmp[20];
	int ofs = 11;
	if (strncmp(refname, "refs/heads/", ofs))
		return 0;
	/* If both heads/foo and tags/foo exists, get_sha1 would
	 * get confused.
	 */
	if (get_sha1(refname + ofs, tmp) || memcmp(tmp, sha1, 20))
		ofs = 5;
	return append_ref(refname + ofs, sha1);
}

static int append_tag_ref(const char *refname, const unsigned char *sha1)
{
	if (strncmp(refname, "refs/tags/", 10))
		return 0;
	return append_ref(refname + 5, sha1);
}

static void snarf_refs(int head, int tag)
{
	if (head) {
		int orig_cnt = ref_name_cnt;
		for_each_ref(append_head_ref);
		sort_ref_range(orig_cnt, ref_name_cnt);
	}
	if (tag) {
		int orig_cnt = ref_name_cnt;
		for_each_ref(append_tag_ref);
		sort_ref_range(orig_cnt, ref_name_cnt);
	}
}

static int rev_is_head(char *head_path, int headlen,
		       char *name,
		       unsigned char *head_sha1, unsigned char *sha1)
{
	int namelen;
	if ((!head_path[0]) || memcmp(head_sha1, sha1, 20))
		return 0;
	namelen = strlen(name);
	if ((headlen < namelen) ||
	    memcmp(head_path + headlen - namelen, name, namelen))
		return 0;
	if (headlen == namelen ||
	    head_path[headlen - namelen - 1] == '/')
		return 1;
	return 0;
}

static int show_merge_base(struct commit_list *seen, int num_rev)
{
	int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
	int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
	int exit_status = 1;

	while (seen) {
		struct commit *commit = pop_one_commit(&seen);
		int flags = commit->object.flags & all_mask;
		if (!(flags & UNINTERESTING) &&
		    ((flags & all_revs) == all_revs)) {
			puts(sha1_to_hex(commit->object.sha1));
			exit_status = 0;
			commit->object.flags |= UNINTERESTING;
		}
	}
	return exit_status;
}

static int show_independent(struct commit **rev,
			    int num_rev,
			    char **ref_name,
			    unsigned int *rev_mask)
{
	int i;

	for (i = 0; i < num_rev; i++) {
		struct commit *commit = rev[i];
		unsigned int flag = rev_mask[i];

		if (commit->object.flags == flag)
			puts(sha1_to_hex(commit->object.sha1));
		commit->object.flags |= UNINTERESTING;
	}
	return 0;
}

int main(int ac, char **av)
{
	struct commit *rev[MAX_REVS], *commit;
	struct commit_list *list = NULL, *seen = NULL;
	unsigned int rev_mask[MAX_REVS];
	int num_rev, i, extra = 0;
	int all_heads = 0, all_tags = 0;
	int all_mask, all_revs;
	char head_path[128];
	const char *head_path_p;
	int head_path_len;
	unsigned char head_sha1[20];
	int merge_base = 0;
	int independent = 0;
	int no_name = 0;
	int sha1_name = 0;
	int shown_merge_point = 0;
	int topo_order = 0;

	setup_git_directory();

	while (1 < ac && av[1][0] == '-') {
		char *arg = av[1];
		if (!strcmp(arg, "--all"))
			all_heads = all_tags = 1;
		else if (!strcmp(arg, "--heads"))
			all_heads = 1;
		else if (!strcmp(arg, "--tags"))
			all_tags = 1;
		else if (!strcmp(arg, "--more"))
			extra = 1;
		else if (!strcmp(arg, "--list"))
			extra = -1;
		else if (!strcmp(arg, "--no-name"))
			no_name = 1;
		else if (!strcmp(arg, "--sha1-name"))
			sha1_name = 1;
		else if (!strncmp(arg, "--more=", 7))
			extra = atoi(arg + 7);
		else if (!strcmp(arg, "--merge-base"))
			merge_base = 1;
		else if (!strcmp(arg, "--independent"))
			independent = 1;
		else if (!strcmp(arg, "--topo-order"))
			topo_order = 1;
		else
			usage(show_branch_usage);
		ac--; av++;
	}
	ac--; av++;

	/* Only one of these is allowed */
	if (1 < independent + merge_base + (extra != 0))
		usage(show_branch_usage);

	if (all_heads + all_tags)
		snarf_refs(all_heads, all_tags);

	while (0 < ac) {
		unsigned char revkey[20];
		if (get_sha1(*av, revkey))
			die("bad sha1 reference %s", *av);
		append_ref(*av, revkey);
		ac--; av++;
	}

	/* If still no revs, then add heads */
	if (!ref_name_cnt)
		snarf_refs(1, 0);

	for (num_rev = 0; ref_name[num_rev]; num_rev++) {
		unsigned char revkey[20];
		unsigned int flag = 1u << (num_rev + REV_SHIFT);

		if (MAX_REVS <= num_rev)
			die("cannot handle more than %d revs.", MAX_REVS);
		if (get_sha1(ref_name[num_rev], revkey))
			die("'%s' is not a valid ref.\n", ref_name[num_rev]);
		commit = lookup_commit_reference(revkey);
		if (!commit)
			die("cannot find commit %s (%s)",
			    ref_name[num_rev], revkey);
		parse_commit(commit);
		mark_seen(commit, &seen);

		/* rev#0 uses bit REV_SHIFT, rev#1 uses bit REV_SHIFT+1,
		 * and so on.  REV_SHIFT bits from bit 0 are used for
		 * internal bookkeeping.
		 */
		commit->object.flags |= flag;
		if (commit->object.flags == flag)
			insert_by_date(commit, &list);
		rev[num_rev] = commit;
	}
	for (i = 0; i < num_rev; i++)
		rev_mask[i] = rev[i]->object.flags;

	if (0 <= extra)
		join_revs(&list, &seen, num_rev, extra);

	head_path_p = resolve_ref(git_path("HEAD"), head_sha1, 1);
	if (head_path_p) {
		head_path_len = strlen(head_path_p);
		memcpy(head_path, head_path_p, head_path_len + 1);
	}
	else {
		head_path_len = 0;
		head_path[0] = 0;
	}

	if (merge_base)
		return show_merge_base(seen, num_rev);

	if (independent)
		return show_independent(rev, num_rev, ref_name, rev_mask);

	/* Show list; --more=-1 means list-only */
	if (1 < num_rev || extra < 0) {
		for (i = 0; i < num_rev; i++) {
			int j;
			int is_head = rev_is_head(head_path,
						  head_path_len,
						  ref_name[i],
						  head_sha1,
						  rev[i]->object.sha1);
			if (extra < 0)
				printf("%c [%s] ",
				       is_head ? '*' : ' ', ref_name[i]);
			else {
				for (j = 0; j < i; j++)
					putchar(' ');
				printf("%c [%s] ",
				       is_head ? '*' : '!', ref_name[i]);
			}
			/* header lines never need name */
			show_one_commit(rev[i], 1);
		}
		if (0 <= extra) {
			for (i = 0; i < num_rev; i++)
				putchar('-');
			putchar('\n');
		}
	}
	if (extra < 0)
		exit(0);

	/* Sort topologically */
	if (topo_order)
		sort_in_topological_order(&seen);

	/* Give names to commits */
	if (!sha1_name && !no_name)
		name_commits(seen, rev, ref_name, num_rev);

	all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
	all_revs = all_mask & ~((1u << REV_SHIFT) - 1);

	while (seen) {
		struct commit *commit = pop_one_commit(&seen);
		int this_flag = commit->object.flags;

		shown_merge_point |= ((this_flag & all_revs) == all_revs);

		if (1 < num_rev) {
			for (i = 0; i < num_rev; i++)
				putchar((this_flag & (1u << (i + REV_SHIFT)))
					? '+' : ' ');
			putchar(' ');
		}
		show_one_commit(commit, no_name);

		if (shown_merge_point && --extra < 0)
			break;
	}
	return 0;
}
Commit	Line	Data
f76412ed JH	1	#include <stdlib.h>
	2	#include "cache.h"
	3	#include "commit.h"
	4	#include "refs.h"
	5
	6	static const char show_branch_usage[] =
1f8af483	7	"git-show-branch [--all] [--heads] [--tags] [--more=count \| --list \| --independent \| --merge-base ] [<refs>...]";
f76412ed JH	8
	9	#define UNINTERESTING 01
	10
	11	#define REV_SHIFT 2
	12	#define MAX_REVS 29 /* should not exceed bits_per_int - REV_SHIFT */
	13
	14	static struct commit interesting(struct commit_list list)
	15	{
	16	while (list) {
	17	struct commit *commit = list->item;
	18	list = list->next;
	19	if (commit->object.flags & UNINTERESTING)
	20	continue;
	21	return commit;
	22	}
	23	return NULL;
	24	}
	25
	26	static struct commit pop_one_commit(struct commit_list *list_p)
	27	{
	28	struct commit *commit;
	29	struct commit_list *list;
	30	list = *list_p;
	31	commit = list->item;
	32	*list_p = list->next;
	33	free(list);
	34	return commit;
	35	}
	36
	37	struct commit_name {
8e5dd22b JH	38	const char head_name; / which head's ancestor? */
8e5dd22b JH	39	int generation; /* how many parents away from head_name */
f76412ed JH	40	};
f76412ed JH	41
8e5dd22b	42	/* Name the commit as nth generation ancestor of head_name;
f76412ed JH	43	* we count only the first-parent relationship for naming purposes.
f76412ed JH	44	*/
8e5dd22b	45	static void name_commit(struct commit commit, const char head_name, int nth)
f76412ed JH	46	{
	47	struct commit_name *name;
	48	if (!commit->object.util)
	49	commit->object.util = xmalloc(sizeof(struct commit_name));
	50	name = commit->object.util;
8e5dd22b	51	name->head_name = head_name;
f76412ed JH	52	name->generation = nth;
	53	}
	54
	55	/* Parent is the first parent of the commit. We may name it
8e5dd22b	56	* as (n+1)th generation ancestor of the same head_name as
f76412ed JH	57	* commit is nth generation ancestore of, if that generation
	58	* number is better than the name it already has.
	59	*/
	60	static void name_parent(struct commit commit, struct commit parent)
	61	{
	62	struct commit_name *commit_name = commit->object.util;
	63	struct commit_name *parent_name = parent->object.util;
	64	if (!commit_name)
	65	return;
	66	if (!parent_name \|\|
	67	commit_name->generation + 1 < parent_name->generation)
8e5dd22b	68	name_commit(parent, commit_name->head_name,
f76412ed JH	69	commit_name->generation + 1);
	70	}
	71
8e5dd22b JH	72	static int name_first_parent_chain(struct commit *c)
	73	{
	74	int i = 0;
	75	while (c) {
	76	struct commit *p;
	77	if (!c->object.util)
	78	break;
	79	if (!c->parents)
	80	break;
	81	p = c->parents->item;
	82	if (!p->object.util) {
	83	name_parent(c, p);
	84	i++;
	85	}
	86	c = p;
	87	}
	88	return i;
	89	}
	90
	91	static void name_commits(struct commit_list *list,
	92	struct commit **rev,
	93	char **ref_name,
	94	int num_rev)
	95	{
	96	struct commit_list *cl;
	97	struct commit *c;
	98	int i;
	99
	100	/* First give names to the given heads */
	101	for (cl = list; cl; cl = cl->next) {
	102	c = cl->item;
	103	if (c->object.util)
	104	continue;
	105	for (i = 0; i < num_rev; i++) {
	106	if (rev[i] == c) {
	107	name_commit(c, ref_name[i], 0);
	108	break;
	109	}
	110	}
	111	}
	112
	113	/* Then commits on the first parent ancestry chain */
	114	do {
	115	i = 0;
	116	for (cl = list; cl; cl = cl->next) {
	117	i += name_first_parent_chain(cl->item);
	118	}
	119	} while (i);
	120
	121	/* Finally, any unnamed commits */
	122	do {
	123	i = 0;
	124	for (cl = list; cl; cl = cl->next) {
	125	struct commit_list *parents;
	126	struct commit_name *n;
	127	int nth;
	128	c = cl->item;
	129	if (!c->object.util)
	130	continue;
	131	n = c->object.util;
	132	parents = c->parents;
	133	nth = 0;
	134	while (parents) {
	135	struct commit *p = parents->item;
013f276e	136	char newname[1000], *en;
8e5dd22b JH	137	parents = parents->next;
	138	nth++;
	139	if (p->object.util)
	140	continue;
013f276e	141	en = newname;
fbaf834d JH	142	switch (n->generation) {
fbaf834d JH	143	case 0:
013f276e	144	en += sprintf(en, "%s", n->head_name);
fbaf834d JH	145	break;
fbaf834d JH	146	case 1:
013f276e	147	en += sprintf(en, "%s^", n->head_name);
fbaf834d JH	148	break;
fbaf834d JH	149	default:
013f276e JH	150	en += sprintf(en, "%s~%d",
	151	n->head_name, n->generation);
	152	break;
fbaf834d	153	}
013f276e JH	154	if (nth == 1)
	155	en += sprintf(en, "^");
	156	else
	157	en += sprintf(en, "^%d", nth);
8e5dd22b JH	158	name_commit(p, strdup(newname), 0);
	159	i++;
	160	name_first_parent_chain(p);
	161	}
	162	}
	163	} while (i);
	164	}
	165
f76412ed JH	166	static int mark_seen(struct commit commit, struct commit_list *seen_p)
	167	{
	168	if (!commit->object.flags) {
	169	insert_by_date(commit, seen_p);
	170	return 1;
	171	}
	172	return 0;
	173	}
	174
	175	static void join_revs(struct commit_list **list_p,
	176	struct commit_list **seen_p,
	177	int num_rev, int extra)
	178	{
	179	int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
	180	int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
	181
	182	while (*list_p) {
	183	struct commit_list *parents;
9ce70285	184	int still_interesting = !!interesting(*list_p);
f76412ed JH	185	struct commit *commit = pop_one_commit(list_p);
f76412ed JH	186	int flags = commit->object.flags & all_mask;
f76412ed	187
9ce70285	188	if (!still_interesting && extra <= 0)
f76412ed JH	189	break;
	190
	191	mark_seen(commit, seen_p);
	192	if ((flags & all_revs) == all_revs)
	193	flags \|= UNINTERESTING;
	194	parents = commit->parents;
	195
	196	while (parents) {
	197	struct commit *p = parents->item;
	198	int this_flag = p->object.flags;
	199	parents = parents->next;
f76412ed JH	200	if ((this_flag & flags) == flags)
f76412ed JH	201	continue;
6b209d47 JH	202	if (!p->object.parsed)
6b209d47 JH	203	parse_commit(p);
f76412ed JH	204	if (mark_seen(p, seen_p) && !still_interesting)
	205	extra--;
	206	p->object.flags \|= flags;
	207	insert_by_date(p, list_p);
	208	}
	209	}
6b209d47 JH	210
	211	/*
	212	* Postprocess to complete well-poisoning.
	213	*
	214	* At this point we have all the commits we have seen in
	215	* seen_p list (which happens to be sorted chronologically but
	216	* it does not really matter). Mark anything that can be
	217	* reached from uninteresting commits not interesting.
	218	*/
	219	for (;;) {
	220	int changed = 0;
	221	struct commit_list *s;
	222	for (s = *seen_p; s; s = s->next) {
	223	struct commit *c = s->item;
	224	struct commit_list *parents;
	225
	226	if (((c->object.flags & all_revs) != all_revs) &&
	227	!(c->object.flags & UNINTERESTING))
	228	continue;
	229
	230	/* The current commit is either a merge base or
	231	* already uninteresting one. Mark its parents
	232	* as uninteresting commits _only_ if they are
	233	* already parsed. No reason to find new ones
	234	* here.
	235	*/
	236	parents = c->parents;
	237	while (parents) {
	238	struct commit *p = parents->item;
	239	parents = parents->next;
	240	if (!(p->object.flags & UNINTERESTING)) {
	241	p->object.flags \|= UNINTERESTING;
	242	changed = 1;
	243	}
	244	}
	245	}
	246	if (!changed)
	247	break;
	248	}
f76412ed JH	249	}
f76412ed JH	250
013f276e	251	static void show_one_commit(struct commit *commit, int no_name)
f76412ed	252	{
6b209d47	253	char pretty[256], *cp;
f76412ed	254	struct commit_name *name = commit->object.util;
0a2ba738 JH	255	if (commit->object.parsed)
	256	pretty_print_commit(CMIT_FMT_ONELINE, commit->buffer, ~0,
	257	pretty, sizeof(pretty));
	258	else
	259	strcpy(pretty, "(unavailable)");
f76412ed JH	260	if (!strncmp(pretty, "[PATCH] ", 8))
	261	cp = pretty + 8;
	262	else
	263	cp = pretty;
013f276e JH	264
	265	if (!no_name) {
	266	if (name && name->head_name) {
	267	printf("[%s", name->head_name);
	268	if (name->generation) {
	269	if (name->generation == 1)
	270	printf("^");
	271	else
	272	printf("~%d", name->generation);
	273	}
	274	printf("] ");
	275	}
	276	else
	277	printf("[%s] ",
	278	find_unique_abbrev(commit->object.sha1, 7));
f76412ed JH	279	}
	280	puts(cp);
	281	}
	282
	283	static char *ref_name[MAX_REVS + 1];
	284	static int ref_name_cnt;
	285
628894b2 JH	286	static int compare_ref_name(const void a_, const void b_)
	287	{
	288	const char * consta = a_, const*b = b_;
	289	return strcmp(a, b);
	290	}
	291
	292	static void sort_ref_range(int bottom, int top)
	293	{
	294	qsort(ref_name + bottom, top - bottom, sizeof(ref_name[0]),
	295	compare_ref_name);
	296	}
	297
f76412ed JH	298	static int append_ref(const char refname, const unsigned char sha1)
	299	{
	300	struct commit *commit = lookup_commit_reference_gently(sha1, 1);
	301	if (!commit)
	302	return 0;
79778e46	303	if (MAX_REVS <= ref_name_cnt) {
f76412ed JH	304	fprintf(stderr, "warning: ignoring %s; "
	305	"cannot handle more than %d refs",
	306	refname, MAX_REVS);
	307	return 0;
	308	}
	309	ref_name[ref_name_cnt++] = strdup(refname);
	310	ref_name[ref_name_cnt] = NULL;
	311	return 0;
	312	}
	313
	314	static int append_head_ref(const char refname, const unsigned char sha1)
	315	{
92421502 JH	316	unsigned char tmp[20];
	317	int ofs = 11;
	318	if (strncmp(refname, "refs/heads/", ofs))
f76412ed	319	return 0;
92421502 JH	320	/* If both heads/foo and tags/foo exists, get_sha1 would
	321	* get confused.
	322	*/
	323	if (get_sha1(refname + ofs, tmp) \|\| memcmp(tmp, sha1, 20))
	324	ofs = 5;
	325	return append_ref(refname + ofs, sha1);
f76412ed JH	326	}
	327
	328	static int append_tag_ref(const char refname, const unsigned char sha1)
	329	{
	330	if (strncmp(refname, "refs/tags/", 10))
	331	return 0;
	332	return append_ref(refname + 5, sha1);
	333	}
	334
	335	static void snarf_refs(int head, int tag)
	336	{
628894b2 JH	337	if (head) {
628894b2 JH	338	int orig_cnt = ref_name_cnt;
f76412ed	339	for_each_ref(append_head_ref);
628894b2 JH	340	sort_ref_range(orig_cnt, ref_name_cnt);
	341	}
	342	if (tag) {
	343	int orig_cnt = ref_name_cnt;
f76412ed	344	for_each_ref(append_tag_ref);
628894b2 JH	345	sort_ref_range(orig_cnt, ref_name_cnt);
628894b2 JH	346	}
f76412ed JH	347	}
	348
	349	static int rev_is_head(char *head_path, int headlen,
	350	char *name,
	351	unsigned char head_sha1, unsigned char sha1)
	352	{
	353	int namelen;
	354	if ((!head_path[0]) \|\| memcmp(head_sha1, sha1, 20))
	355	return 0;
	356	namelen = strlen(name);
	357	if ((headlen < namelen) \|\|
	358	memcmp(head_path + headlen - namelen, name, namelen))
	359	return 0;
	360	if (headlen == namelen \|\|
	361	head_path[headlen - namelen - 1] == '/')
	362	return 1;
	363	return 0;
	364	}
	365
	366	static int show_merge_base(struct commit_list *seen, int num_rev)
	367	{
	368	int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
	369	int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
2f0f8b71	370	int exit_status = 1;
f76412ed JH	371
	372	while (seen) {
	373	struct commit *commit = pop_one_commit(&seen);
	374	int flags = commit->object.flags & all_mask;
	375	if (!(flags & UNINTERESTING) &&
	376	((flags & all_revs) == all_revs)) {
	377	puts(sha1_to_hex(commit->object.sha1));
2f0f8b71 JH	378	exit_status = 0;
2f0f8b71 JH	379	commit->object.flags \|= UNINTERESTING;
f76412ed JH	380	}
f76412ed JH	381	}
2f0f8b71	382	return exit_status;
f76412ed JH	383	}
f76412ed JH	384
1f8af483 JH	385	static int show_independent(struct commit **rev,
	386	int num_rev,
	387	char **ref_name,
	388	unsigned int *rev_mask)
	389	{
	390	int i;
	391
	392	for (i = 0; i < num_rev; i++) {
	393	struct commit *commit = rev[i];
	394	unsigned int flag = rev_mask[i];
	395
	396	if (commit->object.flags == flag)
	397	puts(sha1_to_hex(commit->object.sha1));
	398	commit->object.flags \|= UNINTERESTING;
	399	}
	400	return 0;
	401	}
	402
f76412ed JH	403	int main(int ac, char **av)
	404	{
	405	struct commit rev[MAX_REVS], commit;
	406	struct commit_list list = NULL, seen = NULL;
1f8af483	407	unsigned int rev_mask[MAX_REVS];
f76412ed JH	408	int num_rev, i, extra = 0;
f76412ed JH	409	int all_heads = 0, all_tags = 0;
6b209d47	410	int all_mask, all_revs;
f76412ed	411	char head_path[128];
8098a178	412	const char *head_path_p;
f76412ed JH	413	int head_path_len;
	414	unsigned char head_sha1[20];
	415	int merge_base = 0;
1f8af483	416	int independent = 0;
013f276e JH	417	int no_name = 0;
013f276e JH	418	int sha1_name = 0;
6b209d47 JH	419	int shown_merge_point = 0;
6b209d47 JH	420	int topo_order = 0;
f76412ed	421
076b2324 JH	422	setup_git_directory();
076b2324 JH	423
f76412ed JH	424	while (1 < ac && av[1][0] == '-') {
	425	char *arg = av[1];
	426	if (!strcmp(arg, "--all"))
	427	all_heads = all_tags = 1;
	428	else if (!strcmp(arg, "--heads"))
	429	all_heads = 1;
	430	else if (!strcmp(arg, "--tags"))
	431	all_tags = 1;
	432	else if (!strcmp(arg, "--more"))
	433	extra = 1;
1f8af483 JH	434	else if (!strcmp(arg, "--list"))
1f8af483 JH	435	extra = -1;
013f276e JH	436	else if (!strcmp(arg, "--no-name"))
	437	no_name = 1;
	438	else if (!strcmp(arg, "--sha1-name"))
	439	sha1_name = 1;
1f8af483	440	else if (!strncmp(arg, "--more=", 7))
f76412ed	441	extra = atoi(arg + 7);
f76412ed JH	442	else if (!strcmp(arg, "--merge-base"))
f76412ed JH	443	merge_base = 1;
1f8af483 JH	444	else if (!strcmp(arg, "--independent"))
1f8af483 JH	445	independent = 1;
6b209d47 JH	446	else if (!strcmp(arg, "--topo-order"))
6b209d47 JH	447	topo_order = 1;
f76412ed JH	448	else
	449	usage(show_branch_usage);
	450	ac--; av++;
	451	}
	452	ac--; av++;
	453
1f8af483 JH	454	/* Only one of these is allowed */
	455	if (1 < independent + merge_base + (extra != 0))
	456	usage(show_branch_usage);
	457
f76412ed JH	458	if (all_heads + all_tags)
	459	snarf_refs(all_heads, all_tags);
	460
	461	while (0 < ac) {
	462	unsigned char revkey[20];
	463	if (get_sha1(*av, revkey))
	464	die("bad sha1 reference %s", *av);
	465	append_ref(*av, revkey);
	466	ac--; av++;
	467	}
	468
	469	/* If still no revs, then add heads */
	470	if (!ref_name_cnt)
	471	snarf_refs(1, 0);
	472
	473	for (num_rev = 0; ref_name[num_rev]; num_rev++) {
	474	unsigned char revkey[20];
1f8af483	475	unsigned int flag = 1u << (num_rev + REV_SHIFT);
f76412ed JH	476
	477	if (MAX_REVS <= num_rev)
	478	die("cannot handle more than %d revs.", MAX_REVS);
	479	if (get_sha1(ref_name[num_rev], revkey))
92421502	480	die("'%s' is not a valid ref.\n", ref_name[num_rev]);
f76412ed JH	481	commit = lookup_commit_reference(revkey);
	482	if (!commit)
	483	die("cannot find commit %s (%s)",
	484	ref_name[num_rev], revkey);
	485	parse_commit(commit);
f76412ed JH	486	mark_seen(commit, &seen);
	487
	488	/* rev#0 uses bit REV_SHIFT, rev#1 uses bit REV_SHIFT+1,
	489	* and so on. REV_SHIFT bits from bit 0 are used for
	490	* internal bookkeeping.
	491	*/
1f8af483 JH	492	commit->object.flags \|= flag;
	493	if (commit->object.flags == flag)
	494	insert_by_date(commit, &list);
f76412ed JH	495	rev[num_rev] = commit;
f76412ed JH	496	}
1f8af483 JH	497	for (i = 0; i < num_rev; i++)
	498	rev_mask[i] = rev[i]->object.flags;
	499
	500	if (0 <= extra)
	501	join_revs(&list, &seen, num_rev, extra);
f76412ed	502
8098a178 JH	503	head_path_p = resolve_ref(git_path("HEAD"), head_sha1, 1);
	504	if (head_path_p) {
	505	head_path_len = strlen(head_path_p);
	506	memcpy(head_path, head_path_p, head_path_len + 1);
	507	}
	508	else {
	509	head_path_len = 0;
f76412ed	510	head_path[0] = 0;
8098a178	511	}
f76412ed JH	512
	513	if (merge_base)
	514	return show_merge_base(seen, num_rev);
	515
1f8af483 JH	516	if (independent)
	517	return show_independent(rev, num_rev, ref_name, rev_mask);
	518
	519	/* Show list; --more=-1 means list-only */
c9d023b2	520	if (1 < num_rev \|\| extra < 0) {
f76412ed JH	521	for (i = 0; i < num_rev; i++) {
	522	int j;
	523	int is_head = rev_is_head(head_path,
	524	head_path_len,
	525	ref_name[i],
	526	head_sha1,
	527	rev[i]->object.sha1);
1f8af483 JH	528	if (extra < 0)
	529	printf("%c [%s] ",
	530	is_head ? '*' : ' ', ref_name[i]);
	531	else {
	532	for (j = 0; j < i; j++)
	533	putchar(' ');
	534	printf("%c [%s] ",
	535	is_head ? '*' : '!', ref_name[i]);
	536	}
013f276e JH	537	/* header lines never need name */
013f276e JH	538	show_one_commit(rev[i], 1);
f76412ed	539	}
1f8af483 JH	540	if (0 <= extra) {
	541	for (i = 0; i < num_rev; i++)
	542	putchar('-');
	543	putchar('\n');
	544	}
f5e375c9	545	}
1f8af483 JH	546	if (extra < 0)
1f8af483 JH	547	exit(0);
f5e375c9	548
8e5dd22b	549	/* Sort topologically */
6b209d47 JH	550	if (topo_order)
6b209d47 JH	551	sort_in_topological_order(&seen);
8e5dd22b JH	552
8e5dd22b JH	553	/* Give names to commits */
013f276e JH	554	if (!sha1_name && !no_name)
013f276e JH	555	name_commits(seen, rev, ref_name, num_rev);
8e5dd22b JH	556
	557	all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
	558	all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
8e5dd22b	559
f76412ed JH	560	while (seen) {
	561	struct commit *commit = pop_one_commit(&seen);
	562	int this_flag = commit->object.flags;
f5e375c9	563
6b209d47	564	shown_merge_point \|= ((this_flag & all_revs) == all_revs);
8e5dd22b	565
f5e375c9 JH	566	if (1 < num_rev) {
	567	for (i = 0; i < num_rev; i++)
	568	putchar((this_flag & (1u << (i + REV_SHIFT)))
	569	? '+' : ' ');
	570	putchar(' ');
	571	}
013f276e	572	show_one_commit(commit, no_name);
6b209d47 JH	573
	574	if (shown_merge_point && --extra < 0)
	575	break;
f76412ed JH	576	}
	577	return 0;
	578	}