[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 {
				struct combine_diff_path p;
				struct combine_diff_parent filler[5];
			} combine;
			int num_compare_stages = 0;

			combine.p.next = NULL;
			combine.p.len = ce_namelen(ce);
			combine.p.path = xmalloc(combine.p.len + 1);
			memcpy(combine.p.path, ce->name, combine.p.len);
			combine.p.path[combine.p.len] = 0;
			combine.p.mode = 0;
			memset(combine.p.sha1, 0, 20);
			memset(&combine.p.parent[0], 0,
			       sizeof(combine.filler));

			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++;
					memcpy(combine.p.parent[stage-2].sha1,
					       nce->sha1, 20);
					combine.p.parent[stage-2].mode =
						canon_mode(mode);
					combine.p.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(&combine.p, 2,
						   revs->dense_combined_merges,
						   revs);
				free(combine.p.path);
				continue;
			}
			free(combine.p.path);

			/*
			 * 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;
	}

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