[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];
				parents = parents->next;
				nth++;
				if (p->object.util)
					continue;
				sprintf(newname, "%s^%d", n->head_name, 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;
		struct commit *commit = pop_one_commit(list_p);
		int flags = commit->object.flags & all_mask;
		int still_interesting = !!interesting(*list_p);

		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;
			parse_commit(p);
			if (mark_seen(p, seen_p) && !still_interesting)
				extra--;
			p->object.flags |= flags;
			insert_by_date(p, list_p);
		}
	}
}

static void show_one_commit(struct commit *commit)
{
	char pretty[128], *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 (name && name->head_name) {
		printf("[%s", name->head_name);
		if (name->generation)
			printf("~%d", name->generation);
		printf("] ");
	}
	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)
{
	if (strncmp(refname, "refs/heads/", 11))
		return 0;
	return append_ref(refname + 11, 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, shown_merge_point;
	char head_path[128];
	int head_path_len;
	unsigned char head_sha1[20];
	int merge_base = 0;
	int independent = 0;
	char **label;

	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 (!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
			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))
			usage(show_branch_usage);
		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_len = readlink(".git/HEAD", head_path, sizeof(head_path)-1);
	if ((head_path_len < 0) || get_sha1("HEAD", head_sha1))
		head_path[0] = 0;
	else
		head_path[head_path_len] = 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]);
			}
			show_one_commit(rev[i]);
		}
		if (0 <= extra) {
			for (i = 0; i < num_rev; i++)
				putchar('-');
			putchar('\n');
		}
	}
	if (extra < 0)
		exit(0);

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

	/* Give names to commits */
	name_commits(seen, rev, ref_name, num_rev);

	all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
	all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
	shown_merge_point = 0;

	while (seen) {
		struct commit *commit = pop_one_commit(&seen);
		int this_flag = commit->object.flags;
		int is_merge_point = (this_flag & all_revs) == all_revs;
		static char *obvious[] = { "" };

		if (is_merge_point)
			shown_merge_point = 1;

		if (1 < num_rev) {
			for (i = 0; i < num_rev; i++)
				putchar((this_flag & (1u << (i + REV_SHIFT)))
					? '+' : ' ');
			putchar(' ');
		}
		show_one_commit(commit);
		if (num_rev == 1)
			label = obvious;
		if (shown_merge_point && is_merge_point)
			if (--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;
136	char newname[1000];
137	parents = parents->next;
138	nth++;
139	if (p->object.util)
140	continue;
141	sprintf(newname, "%s^%d", n->head_name, nth);
142	name_commit(p, strdup(newname), 0);
143	i++;
144	name_first_parent_chain(p);
145	}
146	}
147	} while (i);
148	}
149
f76412ed JH	150	static int mark_seen(struct commit commit, struct commit_list *seen_p)
	151	{
	152	if (!commit->object.flags) {
	153	insert_by_date(commit, seen_p);
	154	return 1;
	155	}
	156	return 0;
	157	}
	158
	159	static void join_revs(struct commit_list **list_p,
	160	struct commit_list **seen_p,
	161	int num_rev, int extra)
	162	{
	163	int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
	164	int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
	165
	166	while (*list_p) {
	167	struct commit_list *parents;
	168	struct commit *commit = pop_one_commit(list_p);
	169	int flags = commit->object.flags & all_mask;
f76412ed JH	170	int still_interesting = !!interesting(*list_p);
	171
	172	if (!still_interesting && extra < 0)
	173	break;
	174
	175	mark_seen(commit, seen_p);
	176	if ((flags & all_revs) == all_revs)
	177	flags \|= UNINTERESTING;
	178	parents = commit->parents;
	179
	180	while (parents) {
	181	struct commit *p = parents->item;
	182	int this_flag = p->object.flags;
	183	parents = parents->next;
f76412ed JH	184	if ((this_flag & flags) == flags)
	185	continue;
	186	parse_commit(p);
	187	if (mark_seen(p, seen_p) && !still_interesting)
	188	extra--;
	189	p->object.flags \|= flags;
	190	insert_by_date(p, list_p);
	191	}
	192	}
	193	}
	194
8e5dd22b	195	static void show_one_commit(struct commit *commit)
f76412ed JH	196	{
	197	char pretty[128], *cp;
	198	struct commit_name *name = commit->object.util;
0a2ba738 JH	199	if (commit->object.parsed)
	200	pretty_print_commit(CMIT_FMT_ONELINE, commit->buffer, ~0,
	201	pretty, sizeof(pretty));
	202	else
	203	strcpy(pretty, "(unavailable)");
f76412ed JH	204	if (!strncmp(pretty, "[PATCH] ", 8))
	205	cp = pretty + 8;
	206	else
	207	cp = pretty;
8e5dd22b JH	208	if (name && name->head_name) {
8e5dd22b JH	209	printf("[%s", name->head_name);
f76412ed JH	210	if (name->generation)
	211	printf("~%d", name->generation);
	212	printf("] ");
	213	}
	214	puts(cp);
	215	}
	216
	217	static char *ref_name[MAX_REVS + 1];
	218	static int ref_name_cnt;
	219
628894b2 JH	220	static int compare_ref_name(const void a_, const void b_)
	221	{
	222	const char * consta = a_, const*b = b_;
	223	return strcmp(a, b);
	224	}
	225
	226	static void sort_ref_range(int bottom, int top)
	227	{
	228	qsort(ref_name + bottom, top - bottom, sizeof(ref_name[0]),
	229	compare_ref_name);
	230	}
	231
f76412ed JH	232	static int append_ref(const char refname, const unsigned char sha1)
	233	{
	234	struct commit *commit = lookup_commit_reference_gently(sha1, 1);
	235	if (!commit)
	236	return 0;
	237	if (MAX_REVS < ref_name_cnt) {
	238	fprintf(stderr, "warning: ignoring %s; "
	239	"cannot handle more than %d refs",
	240	refname, MAX_REVS);
	241	return 0;
	242	}
	243	ref_name[ref_name_cnt++] = strdup(refname);
	244	ref_name[ref_name_cnt] = NULL;
	245	return 0;
	246	}
	247
	248	static int append_head_ref(const char refname, const unsigned char sha1)
	249	{
	250	if (strncmp(refname, "refs/heads/", 11))
	251	return 0;
628894b2	252	return append_ref(refname + 11, sha1);
f76412ed JH	253	}
	254
	255	static int append_tag_ref(const char refname, const unsigned char sha1)
	256	{
	257	if (strncmp(refname, "refs/tags/", 10))
	258	return 0;
	259	return append_ref(refname + 5, sha1);
	260	}
	261
	262	static void snarf_refs(int head, int tag)
	263	{
628894b2 JH	264	if (head) {
628894b2 JH	265	int orig_cnt = ref_name_cnt;
f76412ed	266	for_each_ref(append_head_ref);
628894b2 JH	267	sort_ref_range(orig_cnt, ref_name_cnt);
	268	}
	269	if (tag) {
	270	int orig_cnt = ref_name_cnt;
f76412ed	271	for_each_ref(append_tag_ref);
628894b2 JH	272	sort_ref_range(orig_cnt, ref_name_cnt);
628894b2 JH	273	}
f76412ed JH	274	}
	275
	276	static int rev_is_head(char *head_path, int headlen,
	277	char *name,
	278	unsigned char head_sha1, unsigned char sha1)
	279	{
	280	int namelen;
	281	if ((!head_path[0]) \|\| memcmp(head_sha1, sha1, 20))
	282	return 0;
	283	namelen = strlen(name);
	284	if ((headlen < namelen) \|\|
	285	memcmp(head_path + headlen - namelen, name, namelen))
	286	return 0;
	287	if (headlen == namelen \|\|
	288	head_path[headlen - namelen - 1] == '/')
	289	return 1;
	290	return 0;
	291	}
	292
	293	static int show_merge_base(struct commit_list *seen, int num_rev)
	294	{
	295	int all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
	296	int all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
2f0f8b71	297	int exit_status = 1;
f76412ed JH	298
	299	while (seen) {
	300	struct commit *commit = pop_one_commit(&seen);
	301	int flags = commit->object.flags & all_mask;
	302	if (!(flags & UNINTERESTING) &&
	303	((flags & all_revs) == all_revs)) {
	304	puts(sha1_to_hex(commit->object.sha1));
2f0f8b71 JH	305	exit_status = 0;
2f0f8b71 JH	306	commit->object.flags \|= UNINTERESTING;
f76412ed JH	307	}
f76412ed JH	308	}
2f0f8b71	309	return exit_status;
f76412ed JH	310	}
f76412ed JH	311
1f8af483 JH	312	static int show_independent(struct commit **rev,
	313	int num_rev,
	314	char **ref_name,
	315	unsigned int *rev_mask)
	316	{
	317	int i;
	318
	319	for (i = 0; i < num_rev; i++) {
	320	struct commit *commit = rev[i];
	321	unsigned int flag = rev_mask[i];
	322
	323	if (commit->object.flags == flag)
	324	puts(sha1_to_hex(commit->object.sha1));
	325	commit->object.flags \|= UNINTERESTING;
	326	}
	327	return 0;
	328	}
	329
f76412ed JH	330	int main(int ac, char **av)
	331	{
	332	struct commit rev[MAX_REVS], commit;
	333	struct commit_list list = NULL, seen = NULL;
1f8af483	334	unsigned int rev_mask[MAX_REVS];
f76412ed JH	335	int num_rev, i, extra = 0;
f76412ed JH	336	int all_heads = 0, all_tags = 0;
8e5dd22b	337	int all_mask, all_revs, shown_merge_point;
f76412ed JH	338	char head_path[128];
	339	int head_path_len;
	340	unsigned char head_sha1[20];
	341	int merge_base = 0;
1f8af483	342	int independent = 0;
f5e375c9	343	char **label;
f76412ed	344
076b2324 JH	345	setup_git_directory();
076b2324 JH	346
f76412ed JH	347	while (1 < ac && av[1][0] == '-') {
	348	char *arg = av[1];
	349	if (!strcmp(arg, "--all"))
	350	all_heads = all_tags = 1;
	351	else if (!strcmp(arg, "--heads"))
	352	all_heads = 1;
	353	else if (!strcmp(arg, "--tags"))
	354	all_tags = 1;
	355	else if (!strcmp(arg, "--more"))
	356	extra = 1;
1f8af483 JH	357	else if (!strcmp(arg, "--list"))
	358	extra = -1;
	359	else if (!strncmp(arg, "--more=", 7))
f76412ed	360	extra = atoi(arg + 7);
f76412ed JH	361	else if (!strcmp(arg, "--merge-base"))
f76412ed JH	362	merge_base = 1;
1f8af483 JH	363	else if (!strcmp(arg, "--independent"))
1f8af483 JH	364	independent = 1;
f76412ed JH	365	else
	366	usage(show_branch_usage);
	367	ac--; av++;
	368	}
	369	ac--; av++;
	370
1f8af483 JH	371	/* Only one of these is allowed */
	372	if (1 < independent + merge_base + (extra != 0))
	373	usage(show_branch_usage);
	374
f76412ed JH	375	if (all_heads + all_tags)
	376	snarf_refs(all_heads, all_tags);
	377
	378	while (0 < ac) {
	379	unsigned char revkey[20];
	380	if (get_sha1(*av, revkey))
	381	die("bad sha1 reference %s", *av);
	382	append_ref(*av, revkey);
	383	ac--; av++;
	384	}
	385
	386	/* If still no revs, then add heads */
	387	if (!ref_name_cnt)
	388	snarf_refs(1, 0);
	389
	390	for (num_rev = 0; ref_name[num_rev]; num_rev++) {
	391	unsigned char revkey[20];
1f8af483	392	unsigned int flag = 1u << (num_rev + REV_SHIFT);
f76412ed JH	393
	394	if (MAX_REVS <= num_rev)
	395	die("cannot handle more than %d revs.", MAX_REVS);
	396	if (get_sha1(ref_name[num_rev], revkey))
	397	usage(show_branch_usage);
	398	commit = lookup_commit_reference(revkey);
	399	if (!commit)
	400	die("cannot find commit %s (%s)",
	401	ref_name[num_rev], revkey);
	402	parse_commit(commit);
f76412ed JH	403	mark_seen(commit, &seen);
	404
	405	/* rev#0 uses bit REV_SHIFT, rev#1 uses bit REV_SHIFT+1,
	406	* and so on. REV_SHIFT bits from bit 0 are used for
	407	* internal bookkeeping.
	408	*/
1f8af483 JH	409	commit->object.flags \|= flag;
	410	if (commit->object.flags == flag)
	411	insert_by_date(commit, &list);
f76412ed JH	412	rev[num_rev] = commit;
f76412ed JH	413	}
1f8af483 JH	414	for (i = 0; i < num_rev; i++)
	415	rev_mask[i] = rev[i]->object.flags;
	416
	417	if (0 <= extra)
	418	join_revs(&list, &seen, num_rev, extra);
f76412ed JH	419
	420	head_path_len = readlink(".git/HEAD", head_path, sizeof(head_path)-1);
	421	if ((head_path_len < 0) \|\| get_sha1("HEAD", head_sha1))
	422	head_path[0] = 0;
	423	else
	424	head_path[head_path_len] = 0;
	425
	426	if (merge_base)
	427	return show_merge_base(seen, num_rev);
	428
1f8af483 JH	429	if (independent)
	430	return show_independent(rev, num_rev, ref_name, rev_mask);
	431
	432	/* Show list; --more=-1 means list-only */
c9d023b2	433	if (1 < num_rev \|\| extra < 0) {
f76412ed JH	434	for (i = 0; i < num_rev; i++) {
	435	int j;
	436	int is_head = rev_is_head(head_path,
	437	head_path_len,
	438	ref_name[i],
	439	head_sha1,
	440	rev[i]->object.sha1);
1f8af483 JH	441	if (extra < 0)
	442	printf("%c [%s] ",
	443	is_head ? '*' : ' ', ref_name[i]);
	444	else {
	445	for (j = 0; j < i; j++)
	446	putchar(' ');
	447	printf("%c [%s] ",
	448	is_head ? '*' : '!', ref_name[i]);
	449	}
8e5dd22b	450	show_one_commit(rev[i]);
f76412ed	451	}
1f8af483 JH	452	if (0 <= extra) {
	453	for (i = 0; i < num_rev; i++)
	454	putchar('-');
	455	putchar('\n');
	456	}
f5e375c9	457	}
1f8af483 JH	458	if (extra < 0)
1f8af483 JH	459	exit(0);
f5e375c9	460
8e5dd22b JH	461	/* Sort topologically */
	462	sort_in_topological_order(&seen);
	463
	464	/* Give names to commits */
	465	name_commits(seen, rev, ref_name, num_rev);
	466
	467	all_mask = ((1u << (REV_SHIFT + num_rev)) - 1);
	468	all_revs = all_mask & ~((1u << REV_SHIFT) - 1);
	469	shown_merge_point = 0;
	470
f76412ed JH	471	while (seen) {
	472	struct commit *commit = pop_one_commit(&seen);
	473	int this_flag = commit->object.flags;
8e5dd22b	474	int is_merge_point = (this_flag & all_revs) == all_revs;
f5e375c9 JH	475	static char *obvious[] = { "" };
f5e375c9 JH	476
8e5dd22b JH	477	if (is_merge_point)
	478	shown_merge_point = 1;
	479
f5e375c9 JH	480	if (1 < num_rev) {
	481	for (i = 0; i < num_rev; i++)
	482	putchar((this_flag & (1u << (i + REV_SHIFT)))
	483	? '+' : ' ');
	484	putchar(' ');
	485	}
8e5dd22b	486	show_one_commit(commit);
f5e375c9 JH	487	if (num_rev == 1)
f5e375c9 JH	488	label = obvious;
8e5dd22b JH	489	if (shown_merge_point && is_merge_point)
	490	if (--extra < 0)
	491	break;
f76412ed JH	492	}
	493	return 0;
	494	}