[thirdparty/git.git] / diff-lib.c

/*
 * Copyright (C) 2005 Junio C Hamano
 */
#include "cache.h"
#include "quote.h"
#include "commit.h"
#include "diff.h"
#include "diffcore.h"
#include "revision.h"

/*
 * diff-files
 */

int run_diff_files(struct rev_info *revs, int silent_on_removed)
{
	int entries, i;
	int diff_unmerged_stage = revs->max_count;

	if (diff_unmerged_stage < 0)
		diff_unmerged_stage = 2;
	entries = read_cache();
	if (entries < 0) {
		perror("read_cache");
		return -1;
	}
	for (i = 0; i < entries; i++) {
		struct stat st;
		unsigned int oldmode, newmode;
		struct cache_entry *ce = active_cache[i];
		int changed;

		if (!ce_path_match(ce, revs->prune_data))
			continue;

		if (ce_stage(ce)) {
			struct combine_diff_path *dpath;
			int num_compare_stages = 0;
			size_t path_len;

			path_len = ce_namelen(ce);

			dpath = xmalloc (combine_diff_path_size (5, path_len));
			dpath->path = (char *) &(dpath->parent[5]);

			dpath->next = NULL;
			dpath->len = path_len;
			memcpy(dpath->path, ce->name, path_len);
			dpath->path[path_len] = '\0';
			dpath->mode = 0;
			hashclr(dpath->sha1);
			memset(&(dpath->parent[0]), 0,
					sizeof(struct combine_diff_parent)*5);

			while (i < entries) {
				struct cache_entry *nce = active_cache[i];
				int stage;

				if (strcmp(ce->name, nce->name))
					break;

				/* Stage #2 (ours) is the first parent,
				 * stage #3 (theirs) is the second.
				 */
				stage = ce_stage(nce);
				if (2 <= stage) {
					int mode = ntohl(nce->ce_mode);
					num_compare_stages++;
					hashcpy(dpath->parent[stage-2].sha1, nce->sha1);
					dpath->parent[stage-2].mode =
						canon_mode(mode);
					dpath->parent[stage-2].status =
						DIFF_STATUS_MODIFIED;
				}

				/* diff against the proper unmerged stage */
				if (stage == diff_unmerged_stage)
					ce = nce;
				i++;
			}
			/*
			 * Compensate for loop update
			 */
			i--;

			if (revs->combine_merges && num_compare_stages == 2) {
				show_combined_diff(dpath, 2,
						   revs->dense_combined_merges,
						   revs);
				free(dpath);
				continue;
			}
			free(dpath);
			dpath = NULL;

			/*
			 * Show the diff for the 'ce' if we found the one
			 * from the desired stage.
			 */
			diff_unmerge(&revs->diffopt, ce->name);
			if (ce_stage(ce) != diff_unmerged_stage)
				continue;
		}

		if (lstat(ce->name, &st) < 0) {
			if (errno != ENOENT && errno != ENOTDIR) {
				perror(ce->name);
				continue;
			}
			if (silent_on_removed)
				continue;
			diff_addremove(&revs->diffopt, '-', ntohl(ce->ce_mode),
				       ce->sha1, ce->name, NULL);
			continue;
		}
		changed = ce_match_stat(ce, &st, 0);
		if (!changed && !revs->diffopt.find_copies_harder)
			continue;
		oldmode = ntohl(ce->ce_mode);

		newmode = canon_mode(st.st_mode);
		if (!trust_executable_bit &&
		    S_ISREG(newmode) && S_ISREG(oldmode) &&
		    ((newmode ^ oldmode) == 0111))
			newmode = oldmode;
		diff_change(&revs->diffopt, oldmode, newmode,
			    ce->sha1, (changed ? null_sha1 : ce->sha1),
			    ce->name, NULL);

	}
	diffcore_std(&revs->diffopt);
	diff_flush(&revs->diffopt);
	return 0;
}

/*
 * diff-index
 */

/* A file entry went away or appeared */
static void diff_index_show_file(struct rev_info *revs,
				 const char *prefix,
				 struct cache_entry *ce,
				 unsigned char *sha1, unsigned int mode)
{
	diff_addremove(&revs->diffopt, prefix[0], ntohl(mode),
		       sha1, ce->name, NULL);
}

static int get_stat_data(struct cache_entry *ce,
			 unsigned char **sha1p,
			 unsigned int *modep,
			 int cached, int match_missing)
{
	unsigned char *sha1 = ce->sha1;
	unsigned int mode = ce->ce_mode;

	if (!cached) {
		static unsigned char no_sha1[20];
		int changed;
		struct stat st;
		if (lstat(ce->name, &st) < 0) {
			if (errno == ENOENT && match_missing) {
				*sha1p = sha1;
				*modep = mode;
				return 0;
			}
			return -1;
		}
		changed = ce_match_stat(ce, &st, 0);
		if (changed) {
			mode = create_ce_mode(st.st_mode);
			if (!trust_executable_bit && S_ISREG(st.st_mode))
				mode = ce->ce_mode;
			sha1 = no_sha1;
		}
	}

	*sha1p = sha1;
	*modep = mode;
	return 0;
}

static void show_new_file(struct rev_info *revs,
			  struct cache_entry *new,
			  int cached, int match_missing)
{
	unsigned char *sha1;
	unsigned int mode;

	/* New file in the index: it might actually be different in
	 * the working copy.
	 */
	if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0)
		return;

	diff_index_show_file(revs, "+", new, sha1, mode);
}

static int show_modified(struct rev_info *revs,
			 struct cache_entry *old,
			 struct cache_entry *new,
			 int report_missing,
			 int cached, int match_missing)
{
	unsigned int mode, oldmode;
	unsigned char *sha1;

	if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0) {
		if (report_missing)
			diff_index_show_file(revs, "-", old,
					     old->sha1, old->ce_mode);
		return -1;
	}

	if (revs->combine_merges && !cached &&
	    (hashcmp(sha1, old->sha1) || hashcmp(old->sha1, new->sha1))) {
		struct combine_diff_path *p;
		int pathlen = ce_namelen(new);

		p = xmalloc(combine_diff_path_size(2, pathlen));
		p->path = (char *) &p->parent[2];
		p->next = NULL;
		p->len = pathlen;
		memcpy(p->path, new->name, pathlen);
		p->path[pathlen] = 0;
		p->mode = ntohl(mode);
		hashclr(p->sha1);
		memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
		p->parent[0].status = DIFF_STATUS_MODIFIED;
		p->parent[0].mode = ntohl(new->ce_mode);
		hashcpy(p->parent[0].sha1, new->sha1);
		p->parent[1].status = DIFF_STATUS_MODIFIED;
		p->parent[1].mode = ntohl(old->ce_mode);
		hashcpy(p->parent[1].sha1, old->sha1);
		show_combined_diff(p, 2, revs->dense_combined_merges, revs);
		free(p);
		return 0;
	}

	oldmode = old->ce_mode;
	if (mode == oldmode && !hashcmp(sha1, old->sha1) &&
	    !revs->diffopt.find_copies_harder)
		return 0;

	mode = ntohl(mode);
	oldmode = ntohl(oldmode);

	diff_change(&revs->diffopt, oldmode, mode,
		    old->sha1, sha1, old->name, NULL);
	return 0;
}

static int diff_cache(struct rev_info *revs,
		      struct cache_entry **ac, int entries,
		      const char **pathspec,
		      int cached, int match_missing)
{
	while (entries) {
		struct cache_entry *ce = *ac;
		int same = (entries > 1) && ce_same_name(ce, ac[1]);

		if (!ce_path_match(ce, pathspec))
			goto skip_entry;

		switch (ce_stage(ce)) {
		case 0:
			/* No stage 1 entry? That means it's a new file */
			if (!same) {
				show_new_file(revs, ce, cached, match_missing);
				break;
			}
			/* Show difference between old and new */
			show_modified(revs,ac[1], ce, 1,
				      cached, match_missing);
			break;
		case 1:
			/* No stage 3 (merge) entry?
			 * That means it's been deleted.
			 */
			if (!same) {
				diff_index_show_file(revs, "-", ce,
						     ce->sha1, ce->ce_mode);
				break;
			}
			/* We come here with ce pointing at stage 1
			 * (original tree) and ac[1] pointing at stage
			 * 3 (unmerged).  show-modified with
			 * report-missing set to false does not say the
			 * file is deleted but reports true if work
			 * tree does not have it, in which case we
			 * fall through to report the unmerged state.
			 * Otherwise, we show the differences between
			 * the original tree and the work tree.
			 */
			if (!cached &&
			    !show_modified(revs, ce, ac[1], 0,
					   cached, match_missing))
				break;
			/* fallthru */
		case 3:
			diff_unmerge(&revs->diffopt, ce->name);
			break;

		default:
			die("impossible cache entry stage");
		}

skip_entry:
		/*
		 * Ignore all the different stages for this file,
		 * we've handled the relevant cases now.
		 */
		do {
			ac++;
			entries--;
		} while (entries && ce_same_name(ce, ac[0]));
	}
	return 0;
}

/*
 * This turns all merge entries into "stage 3". That guarantees that
 * when we read in the new tree (into "stage 1"), we won't lose sight
 * of the fact that we had unmerged entries.
 */
static void mark_merge_entries(void)
{
	int i;
	for (i = 0; i < active_nr; i++) {
		struct cache_entry *ce = active_cache[i];
		if (!ce_stage(ce))
			continue;
		ce->ce_flags |= htons(CE_STAGEMASK);
	}
}

int run_diff_index(struct rev_info *revs, int cached)
{
	int ret;
	struct object *ent;
	struct tree *tree;
	const char *tree_name;
	int match_missing = 0;

	/* 
	 * Backward compatibility wart - "diff-index -m" does
	 * not mean "do not ignore merges", but totally different.
	 */
	if (!revs->ignore_merges)
		match_missing = 1;

	if (read_cache() < 0) {
		perror("read_cache");
		return -1;
	}
	mark_merge_entries();

	ent = revs->pending.objects[0].item;
	tree_name = revs->pending.objects[0].name;
	tree = parse_tree_indirect(ent->sha1);
	if (!tree)
		return error("bad tree object %s", tree_name);
	if (read_tree(tree, 1, revs->prune_data))
		return error("unable to read tree object %s", tree_name);
	ret = diff_cache(revs, active_cache, active_nr, revs->prune_data,
			 cached, match_missing);
	diffcore_std(&revs->diffopt);
	diff_flush(&revs->diffopt);
	return ret;
}
Commit	Line	Data
be3cfa85 JH	1	/*
	2	* Copyright (C) 2005 Junio C Hamano
	3	*/
86436c28	4	#include "cache.h"
6fb737be	5	#include "quote.h"
6973dcae	6	#include "commit.h"
86436c28	7	#include "diff.h"
427dcb4b	8	#include "diffcore.h"
6973dcae	9	#include "revision.h"
427dcb4b	10
b46f0b6d	11	/*
6973dcae	12	* diff-files
b46f0b6d	13	*/
f0c6b2a2	14
6973dcae	15	int run_diff_files(struct rev_info *revs, int silent_on_removed)
f0c6b2a2	16	{
6973dcae JH	17	int entries, i;
6973dcae JH	18	int diff_unmerged_stage = revs->max_count;
f0c6b2a2	19
6973dcae JH	20	if (diff_unmerged_stage < 0)
	21	diff_unmerged_stage = 2;
	22	entries = read_cache();
	23	if (entries < 0) {
	24	perror("read_cache");
427dcb4b	25	return -1;
427dcb4b	26	}
6973dcae	27	for (i = 0; i < entries; i++) {
be3cfa85	28	struct stat st;
6973dcae JH	29	unsigned int oldmode, newmode;
	30	struct cache_entry *ce = active_cache[i];
	31	int changed;
8676eb43	32
6973dcae	33	if (!ce_path_match(ce, revs->prune_data))
8676eb43	34	continue;
be3cfa85	35
6973dcae	36	if (ce_stage(ce)) {
b4b15503	37	struct combine_diff_path *dpath;
6973dcae	38	int num_compare_stages = 0;
b4b15503	39	size_t path_len;
6973dcae	40
b4b15503 FF	41	path_len = ce_namelen(ce);
	42
	43	dpath = xmalloc (combine_diff_path_size (5, path_len));
	44	dpath->path = (char *) &(dpath->parent[5]);
	45
	46	dpath->next = NULL;
	47	dpath->len = path_len;
	48	memcpy(dpath->path, ce->name, path_len);
	49	dpath->path[path_len] = '\0';
	50	dpath->mode = 0;
a8e0d16d	51	hashclr(dpath->sha1);
b4b15503 FF	52	memset(&(dpath->parent[0]), 0,
b4b15503 FF	53	sizeof(struct combine_diff_parent)*5);
6973dcae JH	54
	55	while (i < entries) {
	56	struct cache_entry *nce = active_cache[i];
	57	int stage;
	58
	59	if (strcmp(ce->name, nce->name))
	60	break;
	61
	62	/* Stage #2 (ours) is the first parent,
	63	* stage #3 (theirs) is the second.
	64	*/
	65	stage = ce_stage(nce);
	66	if (2 <= stage) {
	67	int mode = ntohl(nce->ce_mode);
	68	num_compare_stages++;
e702496e	69	hashcpy(dpath->parent[stage-2].sha1, nce->sha1);
b4b15503	70	dpath->parent[stage-2].mode =
6973dcae	71	canon_mode(mode);
b4b15503	72	dpath->parent[stage-2].status =
6973dcae JH	73	DIFF_STATUS_MODIFIED;
	74	}
	75
	76	/* diff against the proper unmerged stage */
	77	if (stage == diff_unmerged_stage)
	78	ce = nce;
	79	i++;
	80	}
	81	/*
	82	* Compensate for loop update
f0c6b2a2	83	*/
6973dcae	84	i--;
6b5ee137	85
6973dcae	86	if (revs->combine_merges && num_compare_stages == 2) {
b4b15503	87	show_combined_diff(dpath, 2,
6973dcae JH	88	revs->dense_combined_merges,
6973dcae JH	89	revs);
b4b15503	90	free(dpath);
6973dcae	91	continue;
1b1480ff	92	}
b4b15503 FF	93	free(dpath);
b4b15503 FF	94	dpath = NULL;
0e3994fa	95
6973dcae JH	96	/*
	97	* Show the diff for the 'ce' if we found the one
	98	* from the desired stage.
	99	*/
	100	diff_unmerge(&revs->diffopt, ce->name);
	101	if (ce_stage(ce) != diff_unmerged_stage)
	102	continue;
eeaa4603	103	}
6b14d7fa	104
6973dcae JH	105	if (lstat(ce->name, &st) < 0) {
	106	if (errno != ENOENT && errno != ENOTDIR) {
	107	perror(ce->name);
15d061b4 JH	108	continue;
15d061b4 JH	109	}
6973dcae JH	110	if (silent_on_removed)
	111	continue;
	112	diff_addremove(&revs->diffopt, '-', ntohl(ce->ce_mode),
	113	ce->sha1, ce->name, NULL);
	114	continue;
f2ce9fde	115	}
6973dcae JH	116	changed = ce_match_stat(ce, &st, 0);
	117	if (!changed && !revs->diffopt.find_copies_harder)
	118	continue;
	119	oldmode = ntohl(ce->ce_mode);
be3cfa85	120
6973dcae JH	121	newmode = canon_mode(st.st_mode);
	122	if (!trust_executable_bit &&
	123	S_ISREG(newmode) && S_ISREG(oldmode) &&
	124	((newmode ^ oldmode) == 0111))
	125	newmode = oldmode;
	126	diff_change(&revs->diffopt, oldmode, newmode,
	127	ce->sha1, (changed ? null_sha1 : ce->sha1),
	128	ce->name, NULL);
77eb2720	129
7ca45252	130	}
6973dcae JH	131	diffcore_std(&revs->diffopt);
	132	diff_flush(&revs->diffopt);
	133	return 0;
77eb2720	134	}
be3cfa85	135
e09ad6e1 JH	136	/*
	137	* diff-index
	138	*/
	139
	140	/* A file entry went away or appeared */
	141	static void diff_index_show_file(struct rev_info *revs,
	142	const char *prefix,
	143	struct cache_entry *ce,
	144	unsigned char *sha1, unsigned int mode)
	145	{
	146	diff_addremove(&revs->diffopt, prefix[0], ntohl(mode),
	147	sha1, ce->name, NULL);
	148	}
	149
	150	static int get_stat_data(struct cache_entry *ce,
	151	unsigned char **sha1p,
	152	unsigned int *modep,
	153	int cached, int match_missing)
	154	{
	155	unsigned char *sha1 = ce->sha1;
	156	unsigned int mode = ce->ce_mode;
	157
	158	if (!cached) {
	159	static unsigned char no_sha1[20];
	160	int changed;
	161	struct stat st;
	162	if (lstat(ce->name, &st) < 0) {
	163	if (errno == ENOENT && match_missing) {
	164	*sha1p = sha1;
	165	*modep = mode;
	166	return 0;
	167	}
	168	return -1;
	169	}
	170	changed = ce_match_stat(ce, &st, 0);
	171	if (changed) {
	172	mode = create_ce_mode(st.st_mode);
	173	if (!trust_executable_bit && S_ISREG(st.st_mode))
	174	mode = ce->ce_mode;
	175	sha1 = no_sha1;
	176	}
	177	}
	178
	179	*sha1p = sha1;
	180	*modep = mode;
	181	return 0;
	182	}
	183
	184	static void show_new_file(struct rev_info *revs,
	185	struct cache_entry *new,
	186	int cached, int match_missing)
	187	{
	188	unsigned char *sha1;
	189	unsigned int mode;
	190
	191	/* New file in the index: it might actually be different in
	192	* the working copy.
	193	*/
	194	if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0)
	195	return;
	196
	197	diff_index_show_file(revs, "+", new, sha1, mode);
	198	}
	199
200	static int show_modified(struct rev_info *revs,
201	struct cache_entry *old,
202	struct cache_entry *new,
203	int report_missing,
204	int cached, int match_missing)
205	{
206	unsigned int mode, oldmode;
207	unsigned char *sha1;
208
209	if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0) {
210	if (report_missing)
211	diff_index_show_file(revs, "-", old,
212	old->sha1, old->ce_mode);
213	return -1;
214	}
215
cb2b9f5e PM	216	if (revs->combine_merges && !cached &&
	217	(hashcmp(sha1, old->sha1) \|\| hashcmp(old->sha1, new->sha1))) {
	218	struct combine_diff_path *p;
	219	int pathlen = ce_namelen(new);
	220
	221	p = xmalloc(combine_diff_path_size(2, pathlen));
	222	p->path = (char *) &p->parent[2];
	223	p->next = NULL;
	224	p->len = pathlen;
	225	memcpy(p->path, new->name, pathlen);
	226	p->path[pathlen] = 0;
	227	p->mode = ntohl(mode);
	228	hashclr(p->sha1);
	229	memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
	230	p->parent[0].status = DIFF_STATUS_MODIFIED;
	231	p->parent[0].mode = ntohl(new->ce_mode);
	232	hashcpy(p->parent[0].sha1, new->sha1);
	233	p->parent[1].status = DIFF_STATUS_MODIFIED;
	234	p->parent[1].mode = ntohl(old->ce_mode);
	235	hashcpy(p->parent[1].sha1, old->sha1);
	236	show_combined_diff(p, 2, revs->dense_combined_merges, revs);
	237	free(p);
	238	return 0;
	239	}
	240
e09ad6e1	241	oldmode = old->ce_mode;
a89fccd2	242	if (mode == oldmode && !hashcmp(sha1, old->sha1) &&
e09ad6e1 JH	243	!revs->diffopt.find_copies_harder)
	244	return 0;
	245
	246	mode = ntohl(mode);
	247	oldmode = ntohl(oldmode);
	248
	249	diff_change(&revs->diffopt, oldmode, mode,
	250	old->sha1, sha1, old->name, NULL);
	251	return 0;
	252	}
	253
	254	static int diff_cache(struct rev_info *revs,
	255	struct cache_entry **ac, int entries,
	256	const char **pathspec,
	257	int cached, int match_missing)
	258	{
	259	while (entries) {
	260	struct cache_entry ce = ac;
	261	int same = (entries > 1) && ce_same_name(ce, ac[1]);
	262
	263	if (!ce_path_match(ce, pathspec))
	264	goto skip_entry;
	265
	266	switch (ce_stage(ce)) {
	267	case 0:
	268	/* No stage 1 entry? That means it's a new file */
	269	if (!same) {
	270	show_new_file(revs, ce, cached, match_missing);
	271	break;
	272	}
	273	/* Show difference between old and new */
	274	show_modified(revs,ac[1], ce, 1,
	275	cached, match_missing);
	276	break;
	277	case 1:
	278	/* No stage 3 (merge) entry?
	279	* That means it's been deleted.
	280	*/
	281	if (!same) {
	282	diff_index_show_file(revs, "-", ce,
	283	ce->sha1, ce->ce_mode);
	284	break;
	285	}
	286	/* We come here with ce pointing at stage 1
	287	* (original tree) and ac[1] pointing at stage
	288	* 3 (unmerged). show-modified with
	289	* report-missing set to false does not say the
	290	* file is deleted but reports true if work
	291	* tree does not have it, in which case we
	292	* fall through to report the unmerged state.
	293	* Otherwise, we show the differences between
	294	* the original tree and the work tree.
	295	*/
	296	if (!cached &&
	297	!show_modified(revs, ce, ac[1], 0,
	298	cached, match_missing))
	299	break;
	300	/* fallthru */
	301	case 3:
	302	diff_unmerge(&revs->diffopt, ce->name);
	303	break;
	304
	305	default:
	306	die("impossible cache entry stage");
307	}
308
309	skip_entry:
310	/*
311	* Ignore all the different stages for this file,
312	* we've handled the relevant cases now.
313	*/
314	do {
315	ac++;
316	entries--;
317	} while (entries && ce_same_name(ce, ac[0]));
318	}
319	return 0;
320	}
321
322	/*
323	* This turns all merge entries into "stage 3". That guarantees that
324	* when we read in the new tree (into "stage 1"), we won't lose sight
325	* of the fact that we had unmerged entries.
326	*/
327	static void mark_merge_entries(void)
328	{
329	int i;
330	for (i = 0; i < active_nr; i++) {
331	struct cache_entry *ce = active_cache[i];
332	if (!ce_stage(ce))
333	continue;
334	ce->ce_flags \|= htons(CE_STAGEMASK);
335	}
336	}
337
5c21ac0e	338	int run_diff_index(struct rev_info *revs, int cached)
e09ad6e1 JH	339	{
	340	int ret;
	341	struct object *ent;
	342	struct tree *tree;
	343	const char *tree_name;
5c21ac0e JH	344	int match_missing = 0;
	345
	346	/*
	347	* Backward compatibility wart - "diff-index -m" does
	348	* not mean "do not ignore merges", but totally different.
	349	*/
	350	if (!revs->ignore_merges)
	351	match_missing = 1;
e09ad6e1 JH	352
	353	if (read_cache() < 0) {
	354	perror("read_cache");
	355	return -1;
	356	}
	357	mark_merge_entries();
	358
1f1e895f LT	359	ent = revs->pending.objects[0].item;
1f1e895f LT	360	tree_name = revs->pending.objects[0].name;
e09ad6e1 JH	361	tree = parse_tree_indirect(ent->sha1);
	362	if (!tree)
	363	return error("bad tree object %s", tree_name);
	364	if (read_tree(tree, 1, revs->prune_data))
	365	return error("unable to read tree object %s", tree_name);
	366	ret = diff_cache(revs, active_cache, active_nr, revs->prune_data,
	367	cached, match_missing);
	368	diffcore_std(&revs->diffopt);
	369	diff_flush(&revs->diffopt);
	370	return ret;
	371	}