git

1
/*
2
 * Copyright (C) 2005 Junio C Hamano
3
 */
4

5
#define USE_THE_REPOSITORY_VARIABLE
6

7
#include "git-compat-util.h"
8
#include "commit.h"
9
#include "diff.h"
10
#include "diffcore.h"
11
#include "gettext.h"
12
#include "hash.h"
13
#include "hex.h"
14
#include "object-name.h"
15
#include "read-cache.h"
16
#include "revision.h"
17
#include "cache-tree.h"
18
#include "unpack-trees.h"
19
#include "refs.h"
20
#include "repository.h"
21
#include "submodule.h"
22
#include "symlinks.h"
23
#include "trace.h"
24
#include "dir.h"
25
#include "fsmonitor.h"
26
#include "commit-reach.h"
27

28
/*
29
 * diff-files
30
 */
31

32
/*
33
 * Has the work tree entity been removed?
34
 *
35
 * Return 1 if it was removed from the work tree, 0 if an entity to be
36
 * compared with the cache entry ce still exists (the latter includes
37
 * the case where a directory that is not a submodule repository
38
 * exists for ce that is a submodule -- it is a submodule that is not
39
 * checked out).  Return negative for an error.
40
 */
41
static int check_removed(const struct cache_entry *ce, struct stat *st)
42
{
43
	int stat_err;
44

45
	if (!(ce->ce_flags & CE_FSMONITOR_VALID))
46
		stat_err = lstat(ce->name, st);
47
	else
48
		stat_err = fake_lstat(ce, st);
49
	if (stat_err < 0) {
50
		if (!is_missing_file_error(errno))
51
			return -1;
52
		return 1;
53
	}
54

55
	if (has_symlink_leading_path(ce->name, ce_namelen(ce)))
56
		return 1;
57
	if (S_ISDIR(st->st_mode)) {
58
		struct object_id sub;
59

60
		/*
61
		 * If ce is already a gitlink, we can have a plain
62
		 * directory (i.e. the submodule is not checked out),
63
		 * or a checked out submodule.  Either case this is not
64
		 * a case where something was removed from the work tree,
65
		 * so we will return 0.
66
		 *
67
		 * Otherwise, if the directory is not a submodule
68
		 * repository, that means ce which was a blob turned into
69
		 * a directory --- the blob was removed!
70
		 */
71
		if (!S_ISGITLINK(ce->ce_mode) &&
72
		    repo_resolve_gitlink_ref(the_repository, ce->name,
73
					     "HEAD", &sub))
74
			return 1;
75
	}
76
	return 0;
77
}
78

79
/*
80
 * Has a file changed or has a submodule new commits or a dirty work tree?
81
 *
82
 * Return 1 when changes are detected, 0 otherwise. If the DIRTY_SUBMODULES
83
 * option is set, the caller does not only want to know if a submodule is
84
 * modified at all but wants to know all the conditions that are met (new
85
 * commits, untracked content and/or modified content).
86
 */
87
static int match_stat_with_submodule(struct diff_options *diffopt,
88
				     const struct cache_entry *ce,
89
				     struct stat *st, unsigned ce_option,
90
				     unsigned *dirty_submodule)
91
{
92
	int changed = ie_match_stat(diffopt->repo->index, ce, st, ce_option);
93
	if (S_ISGITLINK(ce->ce_mode)) {
94
		struct diff_flags orig_flags = diffopt->flags;
95
		if (!diffopt->flags.override_submodule_config)
96
			set_diffopt_flags_from_submodule_config(diffopt, ce->name);
97
		if (diffopt->flags.ignore_submodules)
98
			changed = 0;
99
		else if (!diffopt->flags.ignore_dirty_submodules &&
100
			 (!changed || diffopt->flags.dirty_submodules))
101
			*dirty_submodule = is_submodule_modified(ce->name,
102
								 diffopt->flags.ignore_untracked_in_submodules);
103
		diffopt->flags = orig_flags;
104
	}
105
	return changed;
106
}
107

108
void run_diff_files(struct rev_info *revs, unsigned int option)
109
{
110
	int entries, i;
111
	int diff_unmerged_stage = revs->max_count;
112
	unsigned ce_option = ((option & DIFF_RACY_IS_MODIFIED)
113
			      ? CE_MATCH_RACY_IS_DIRTY : 0);
114
	uint64_t start = getnanotime();
115
	struct index_state *istate = revs->diffopt.repo->index;
116

117
	diff_set_mnemonic_prefix(&revs->diffopt, "i/", "w/");
118

119
	refresh_fsmonitor(istate);
120

121
	if (diff_unmerged_stage < 0)
122
		diff_unmerged_stage = 2;
123
	entries = istate->cache_nr;
124
	for (i = 0; i < entries; i++) {
125
		unsigned int oldmode, newmode;
126
		struct cache_entry *ce = istate->cache[i];
127
		int changed;
128
		unsigned dirty_submodule = 0;
129
		const struct object_id *old_oid, *new_oid;
130

131
		if (diff_can_quit_early(&revs->diffopt))
132
			break;
133

134
		/*
135
		 * NEEDSWORK:
136
		 * Here we filter with pathspec but the result is further
137
		 * filtered out when --relative is in effect.  To end-users,
138
		 * a pathspec element that matched only to paths outside the
139
		 * current directory is like not matching anything at all;
140
		 * the handling of ps_matched[] here may become problematic
141
		 * if/when we add the "--error-unmatch" option to "git diff".
142
		 */
143
		if (!ce_path_match(istate, ce, &revs->prune_data, revs->ps_matched))
144
			continue;
145

146
		if (revs->diffopt.prefix &&
147
		    strncmp(ce->name, revs->diffopt.prefix, revs->diffopt.prefix_length))
148
			continue;
149

150
		if (ce_stage(ce)) {
151
			struct combine_diff_path *dpath;
152
			struct diff_filepair *pair;
153
			unsigned int wt_mode = 0;
154
			int num_compare_stages = 0;
155
			size_t path_len;
156
			struct stat st;
157

158
			path_len = ce_namelen(ce);
159

160
			dpath = xmalloc(combine_diff_path_size(5, path_len));
161
			dpath->path = (char *) &(dpath->parent[5]);
162

163
			dpath->next = NULL;
164
			memcpy(dpath->path, ce->name, path_len);
165
			dpath->path[path_len] = '\0';
166
			oidclr(&dpath->oid, the_repository->hash_algo);
167
			memset(&(dpath->parent[0]), 0,
168
			       sizeof(struct combine_diff_parent)*5);
169

170
			changed = check_removed(ce, &st);
171
			if (!changed)
172
				wt_mode = ce_mode_from_stat(ce, st.st_mode);
173
			else {
174
				if (changed < 0) {
175
					perror(ce->name);
176
					continue;
177
				}
178
				wt_mode = 0;
179
			}
180
			dpath->mode = wt_mode;
181

182
			while (i < entries) {
183
				struct cache_entry *nce = istate->cache[i];
184
				int stage;
185

186
				if (strcmp(ce->name, nce->name))
187
					break;
188

189
				/* Stage #2 (ours) is the first parent,
190
				 * stage #3 (theirs) is the second.
191
				 */
192
				stage = ce_stage(nce);
193
				if (2 <= stage) {
194
					int mode = nce->ce_mode;
195
					num_compare_stages++;
196
					oidcpy(&dpath->parent[stage - 2].oid,
197
					       &nce->oid);
198
					dpath->parent[stage-2].mode = ce_mode_from_stat(nce, mode);
199
					dpath->parent[stage-2].status =
200
						DIFF_STATUS_MODIFIED;
201
				}
202

203
				/* diff against the proper unmerged stage */
204
				if (stage == diff_unmerged_stage)
205
					ce = nce;
206
				i++;
207
			}
208
			/*
209
			 * Compensate for loop update
210
			 */
211
			i--;
212

213
			if (revs->combine_merges && num_compare_stages == 2) {
214
				show_combined_diff(dpath, 2, revs);
215
				free(dpath);
216
				continue;
217
			}
218
			FREE_AND_NULL(dpath);
219

220
			/*
221
			 * Show the diff for the 'ce' if we found the one
222
			 * from the desired stage.
223
			 */
224
			pair = diff_unmerge(&revs->diffopt, ce->name);
225
			if (wt_mode)
226
				pair->two->mode = wt_mode;
227
			if (ce_stage(ce) != diff_unmerged_stage)
228
				continue;
229
		}
230

231
		if (ce_uptodate(ce) || ce_skip_worktree(ce))
232
			continue;
233

234
		/*
235
		 * When CE_VALID is set (via "update-index --assume-unchanged"
236
		 * or via adding paths while core.ignorestat is set to true),
237
		 * the user has promised that the working tree file for that
238
		 * path will not be modified.  When CE_FSMONITOR_VALID is true,
239
		 * the fsmonitor knows that the path hasn't been modified since
240
		 * we refreshed the cached stat information.  In either case,
241
		 * we do not have to stat to see if the path has been removed
242
		 * or modified.
243
		 */
244
		if (ce->ce_flags & (CE_VALID | CE_FSMONITOR_VALID)) {
245
			changed = 0;
246
			newmode = ce->ce_mode;
247
		} else {
248
			struct stat st;
249

250
			changed = check_removed(ce, &st);
251
			if (changed) {
252
				if (changed < 0) {
253
					perror(ce->name);
254
					continue;
255
				}
256
				diff_addremove(&revs->diffopt, '-', ce->ce_mode,
257
					       &ce->oid,
258
					       !is_null_oid(&ce->oid),
259
					       ce->name, 0);
260
				continue;
261
			} else if (revs->diffopt.ita_invisible_in_index &&
262
				   ce_intent_to_add(ce)) {
263
				newmode = ce_mode_from_stat(ce, st.st_mode);
264
				diff_addremove(&revs->diffopt, '+', newmode,
265
					       null_oid(), 0, ce->name, 0);
266
				continue;
267
			}
268

269
			changed = match_stat_with_submodule(&revs->diffopt, ce, &st,
270
							    ce_option, &dirty_submodule);
271
			newmode = ce_mode_from_stat(ce, st.st_mode);
272
		}
273

274
		if (!changed && !dirty_submodule) {
275
			ce_mark_uptodate(ce);
276
			mark_fsmonitor_valid(istate, ce);
277
			if (!revs->diffopt.flags.find_copies_harder)
278
				continue;
279
		}
280
		oldmode = ce->ce_mode;
281
		old_oid = &ce->oid;
282
		new_oid = changed ? null_oid() : &ce->oid;
283
		diff_change(&revs->diffopt, oldmode, newmode,
284
			    old_oid, new_oid,
285
			    !is_null_oid(old_oid),
286
			    !is_null_oid(new_oid),
287
			    ce->name, 0, dirty_submodule);
288

289
	}
290
	diffcore_std(&revs->diffopt);
291
	diff_flush(&revs->diffopt);
292
	trace_performance_since(start, "diff-files");
293
}
294

295
/*
296
 * diff-index
297
 */
298

299
/* A file entry went away or appeared */
300
static void diff_index_show_file(struct rev_info *revs,
301
				 const char *prefix,
302
				 const struct cache_entry *ce,
303
				 const struct object_id *oid, int oid_valid,
304
				 unsigned int mode,
305
				 unsigned dirty_submodule)
306
{
307
	diff_addremove(&revs->diffopt, prefix[0], mode,
308
		       oid, oid_valid, ce->name, dirty_submodule);
309
}
310

311
static int get_stat_data(const struct cache_entry *ce,
312
			 const struct object_id **oidp,
313
			 unsigned int *modep,
314
			 int cached, int match_missing,
315
			 unsigned *dirty_submodule, struct diff_options *diffopt)
316
{
317
	const struct object_id *oid = &ce->oid;
318
	unsigned int mode = ce->ce_mode;
319

320
	if (!cached && !ce_uptodate(ce)) {
321
		int changed;
322
		struct stat st;
323
		changed = check_removed(ce, &st);
324
		if (changed < 0)
325
			return -1;
326
		else if (changed) {
327
			if (match_missing) {
328
				*oidp = oid;
329
				*modep = mode;
330
				return 0;
331
			}
332
			return -1;
333
		}
334
		changed = match_stat_with_submodule(diffopt, ce, &st,
335
						    0, dirty_submodule);
336
		if (changed) {
337
			mode = ce_mode_from_stat(ce, st.st_mode);
338
			oid = null_oid();
339
		}
340
	}
341

342
	*oidp = oid;
343
	*modep = mode;
344
	return 0;
345
}
346

347
static void show_new_file(struct rev_info *revs,
348
			  const struct cache_entry *new_file,
349
			  int cached, int match_missing)
350
{
351
	const struct object_id *oid;
352
	unsigned int mode;
353
	unsigned dirty_submodule = 0;
354

355
	if (new_file && S_ISSPARSEDIR(new_file->ce_mode)) {
356
		diff_tree_oid(NULL, &new_file->oid, new_file->name, &revs->diffopt);
357
		return;
358
	}
359

360
	/*
361
	 * New file in the index: it might actually be different in
362
	 * the working tree.
363
	 */
364
	if (get_stat_data(new_file, &oid, &mode, cached, match_missing,
365
	    &dirty_submodule, &revs->diffopt) < 0)
366
		return;
367

368
	diff_index_show_file(revs, "+", new_file, oid, !is_null_oid(oid), mode, dirty_submodule);
369
}
370

371
static int show_modified(struct rev_info *revs,
372
			 const struct cache_entry *old_entry,
373
			 const struct cache_entry *new_entry,
374
			 int report_missing,
375
			 int cached, int match_missing)
376
{
377
	unsigned int mode, oldmode;
378
	const struct object_id *oid;
379
	unsigned dirty_submodule = 0;
380

381
	assert(S_ISSPARSEDIR(old_entry->ce_mode) ==
382
	       S_ISSPARSEDIR(new_entry->ce_mode));
383

384
	/*
385
	 * If both are sparse directory entries, then expand the
386
	 * modifications to the file level. If only one was a sparse
387
	 * directory, then they appear as an add and delete instead of
388
	 * a modification.
389
	 */
390
	if (S_ISSPARSEDIR(new_entry->ce_mode)) {
391
		diff_tree_oid(&old_entry->oid, &new_entry->oid, new_entry->name, &revs->diffopt);
392
		return 0;
393
	}
394

395
	if (get_stat_data(new_entry, &oid, &mode, cached, match_missing,
396
			  &dirty_submodule, &revs->diffopt) < 0) {
397
		if (report_missing)
398
			diff_index_show_file(revs, "-", old_entry,
399
					     &old_entry->oid, 1, old_entry->ce_mode,
400
					     0);
401
		return -1;
402
	}
403

404
	if (revs->combine_merges && !cached &&
405
	    (!oideq(oid, &old_entry->oid) || !oideq(&old_entry->oid, &new_entry->oid))) {
406
		struct combine_diff_path *p;
407
		int pathlen = ce_namelen(new_entry);
408

409
		p = xmalloc(combine_diff_path_size(2, pathlen));
410
		p->path = (char *) &p->parent[2];
411
		p->next = NULL;
412
		memcpy(p->path, new_entry->name, pathlen);
413
		p->path[pathlen] = 0;
414
		p->mode = mode;
415
		oidclr(&p->oid, the_repository->hash_algo);
416
		memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
417
		p->parent[0].status = DIFF_STATUS_MODIFIED;
418
		p->parent[0].mode = new_entry->ce_mode;
419
		oidcpy(&p->parent[0].oid, &new_entry->oid);
420
		p->parent[1].status = DIFF_STATUS_MODIFIED;
421
		p->parent[1].mode = old_entry->ce_mode;
422
		oidcpy(&p->parent[1].oid, &old_entry->oid);
423
		show_combined_diff(p, 2, revs);
424
		free(p);
425
		return 0;
426
	}
427

428
	oldmode = old_entry->ce_mode;
429
	if (mode == oldmode && oideq(oid, &old_entry->oid) && !dirty_submodule &&
430
	    !revs->diffopt.flags.find_copies_harder)
431
		return 0;
432

433
	diff_change(&revs->diffopt, oldmode, mode,
434
		    &old_entry->oid, oid, 1, !is_null_oid(oid),
435
		    old_entry->name, 0, dirty_submodule);
436
	return 0;
437
}
438

439
/*
440
 * This gets a mix of an existing index and a tree, one pathname entry
441
 * at a time. The index entry may be a single stage-0 one, but it could
442
 * also be multiple unmerged entries (in which case idx_pos/idx_nr will
443
 * give you the position and number of entries in the index).
444
 */
445
static void do_oneway_diff(struct unpack_trees_options *o,
446
			   const struct cache_entry *idx,
447
			   const struct cache_entry *tree)
448
{
449
	struct rev_info *revs = o->unpack_data;
450
	int match_missing, cached;
451

452
	/*
453
	 * i-t-a entries do not actually exist in the index (if we're
454
	 * looking at its content)
455
	 */
456
	if (o->index_only &&
457
	    revs->diffopt.ita_invisible_in_index &&
458
	    idx && ce_intent_to_add(idx)) {
459
		idx = NULL;
460
		if (!tree)
461
			return;	/* nothing to diff.. */
462
	}
463

464
	/* if the entry is not checked out, don't examine work tree */
465
	cached = o->index_only ||
466
		(idx && ((idx->ce_flags & CE_VALID) || ce_skip_worktree(idx)));
467

468
	match_missing = revs->match_missing;
469

470
	if (cached && idx && ce_stage(idx)) {
471
		struct diff_filepair *pair;
472
		pair = diff_unmerge(&revs->diffopt, idx->name);
473
		if (tree)
474
			fill_filespec(pair->one, &tree->oid, 1,
475
				      tree->ce_mode);
476
		return;
477
	}
478

479
	/*
480
	 * Something added to the tree?
481
	 */
482
	if (!tree) {
483
		show_new_file(revs, idx, cached, match_missing);
484
		return;
485
	}
486

487
	/*
488
	 * Something removed from the tree?
489
	 */
490
	if (!idx) {
491
		if (S_ISSPARSEDIR(tree->ce_mode)) {
492
			diff_tree_oid(&tree->oid, NULL, tree->name, &revs->diffopt);
493
			return;
494
		}
495

496
		diff_index_show_file(revs, "-", tree, &tree->oid, 1,
497
				     tree->ce_mode, 0);
498
		return;
499
	}
500

501
	/* Show difference between old and new */
502
	show_modified(revs, tree, idx, 1, cached, match_missing);
503
}
504

505
/*
506
 * The unpack_trees() interface is designed for merging, so
507
 * the different source entries are designed primarily for
508
 * the source trees, with the old index being really mainly
509
 * used for being replaced by the result.
510
 *
511
 * For diffing, the index is more important, and we only have a
512
 * single tree.
513
 *
514
 * We're supposed to advance o->pos to skip what we have already processed.
515
 *
516
 * This wrapper makes it all more readable, and takes care of all
517
 * the fairly complex unpack_trees() semantic requirements, including
518
 * the skipping, the path matching, the type conflict cases etc.
519
 */
520
static int oneway_diff(const struct cache_entry * const *src,
521
		       struct unpack_trees_options *o)
522
{
523
	const struct cache_entry *idx = src[0];
524
	const struct cache_entry *tree = src[1];
525
	struct rev_info *revs = o->unpack_data;
526

527
	/*
528
	 * Unpack-trees generates a DF/conflict entry if
529
	 * there was a directory in the index and a tree
530
	 * in the tree. From a diff standpoint, that's a
531
	 * delete of the tree and a create of the file.
532
	 */
533
	if (tree == o->df_conflict_entry)
534
		tree = NULL;
535

536
	if (ce_path_match(revs->diffopt.repo->index,
537
			  idx ? idx : tree,
538
			  &revs->prune_data, NULL)) {
539
		do_oneway_diff(o, idx, tree);
540
		if (diff_can_quit_early(&revs->diffopt)) {
541
			o->exiting_early = 1;
542
			return -1;
543
		}
544
	}
545

546
	return 0;
547
}
548

549
static int diff_cache(struct rev_info *revs,
550
		      const struct object_id *tree_oid,
551
		      const char *tree_name,
552
		      int cached)
553
{
554
	struct tree *tree;
555
	struct tree_desc t;
556
	struct unpack_trees_options opts;
557

558
	tree = parse_tree_indirect(tree_oid);
559
	if (!tree)
560
		return error("bad tree object %s",
561
			     tree_name ? tree_name : oid_to_hex(tree_oid));
562
	memset(&opts, 0, sizeof(opts));
563
	opts.head_idx = 1;
564
	opts.index_only = cached;
565
	opts.diff_index_cached = (cached &&
566
				  !revs->diffopt.flags.find_copies_harder);
567
	opts.merge = 1;
568
	opts.fn = oneway_diff;
569
	opts.unpack_data = revs;
570
	opts.src_index = revs->diffopt.repo->index;
571
	opts.dst_index = NULL;
572
	opts.pathspec = &revs->diffopt.pathspec;
573
	opts.pathspec->recursive = 1;
574

575
	init_tree_desc(&t, &tree->object.oid, tree->buffer, tree->size);
576
	return unpack_trees(1, &t, &opts);
577
}
578

579
void diff_get_merge_base(const struct rev_info *revs, struct object_id *mb)
580
{
581
	int i;
582
	struct commit *mb_child[2] = {0};
583
	struct commit_list *merge_bases = NULL;
584

585
	for (i = 0; i < revs->pending.nr; i++) {
586
		struct object *obj = revs->pending.objects[i].item;
587
		if (obj->flags)
588
			die(_("--merge-base does not work with ranges"));
589
	}
590

591
	/*
592
	 * This check must go after the for loop above because A...B
593
	 * ranges produce three pending commits, resulting in a
594
	 * misleading error message.
595
	 */
596
	if (revs->pending.nr < 1 || revs->pending.nr > 2)
597
		BUG("unexpected revs->pending.nr: %d", revs->pending.nr);
598

599
	for (i = 0; i < revs->pending.nr; i++)
600
		mb_child[i] = lookup_commit_reference(the_repository, &revs->pending.objects[i].item->oid);
601
	if (revs->pending.nr == 1) {
602
		struct object_id oid;
603

604
		if (repo_get_oid(the_repository, "HEAD", &oid))
605
			die(_("unable to get HEAD"));
606

607
		mb_child[1] = lookup_commit_reference(the_repository, &oid);
608
	}
609

610
	if (repo_get_merge_bases(the_repository, mb_child[0], mb_child[1], &merge_bases) < 0)
611
		exit(128);
612
	if (!merge_bases)
613
		die(_("no merge base found"));
614
	if (merge_bases->next)
615
		die(_("multiple merge bases found"));
616

617
	oidcpy(mb, &merge_bases->item->object.oid);
618

619
	free_commit_list(merge_bases);
620
}
621

622
void run_diff_index(struct rev_info *revs, unsigned int option)
623
{
624
	struct object_array_entry *ent;
625
	int cached = !!(option & DIFF_INDEX_CACHED);
626
	int merge_base = !!(option & DIFF_INDEX_MERGE_BASE);
627
	struct object_id oid;
628
	const char *name;
629
	char merge_base_hex[GIT_MAX_HEXSZ + 1];
630
	struct index_state *istate = revs->diffopt.repo->index;
631

632
	if (revs->pending.nr != 1)
633
		BUG("run_diff_index must be passed exactly one tree");
634

635
	trace_performance_enter();
636
	ent = revs->pending.objects;
637

638
	refresh_fsmonitor(istate);
639

640
	if (merge_base) {
641
		diff_get_merge_base(revs, &oid);
642
		name = oid_to_hex_r(merge_base_hex, &oid);
643
	} else {
644
		oidcpy(&oid, &ent->item->oid);
645
		name = ent->name;
646
	}
647

648
	if (diff_cache(revs, &oid, name, cached))
649
		exit(128);
650

651
	diff_set_mnemonic_prefix(&revs->diffopt, "c/", cached ? "i/" : "w/");
652
	diffcore_fix_diff_index();
653
	diffcore_std(&revs->diffopt);
654
	diff_flush(&revs->diffopt);
655
	trace_performance_leave("diff-index");
656
}
657

658
int do_diff_cache(const struct object_id *tree_oid, struct diff_options *opt)
659
{
660
	struct rev_info revs;
661

662
	repo_init_revisions(opt->repo, &revs, NULL);
663
	copy_pathspec(&revs.prune_data, &opt->pathspec);
664
	revs.diffopt = *opt;
665
	revs.diffopt.no_free = 1;
666

667
	if (diff_cache(&revs, tree_oid, NULL, 1))
668
		exit(128);
669

670
	release_revisions(&revs);
671
	return 0;
672
}
673

674
int index_differs_from(struct repository *r,
675
		       const char *def, const struct diff_flags *flags,
676
		       int ita_invisible_in_index)
677
{
678
	struct rev_info rev;
679
	struct setup_revision_opt opt;
680
	unsigned has_changes;
681

682
	repo_init_revisions(r, &rev, NULL);
683
	memset(&opt, 0, sizeof(opt));
684
	opt.def = def;
685
	setup_revisions(0, NULL, &rev, &opt);
686
	rev.diffopt.flags.quick = 1;
687
	rev.diffopt.flags.exit_with_status = 1;
688
	if (flags) {
689
		diff_flags_or(&rev.diffopt.flags, flags);
690
		/*
691
		 * Now that flags are merged, honor override_submodule_config
692
		 * and ignore_submodules from passed flags.
693
		 */
694
		if (flags->override_submodule_config)
695
			rev.diffopt.flags.ignore_submodules = flags->ignore_submodules;
696
	}
697
	rev.diffopt.ita_invisible_in_index = ita_invisible_in_index;
698
	run_diff_index(&rev, DIFF_INDEX_CACHED);
699
	has_changes = rev.diffopt.flags.has_changes;
700
	release_revisions(&rev);
701
	return (has_changes != 0);
702
}
703

704
static struct strbuf *idiff_prefix_cb(struct diff_options *opt UNUSED, void *data)
705
{
706
	return data;
707
}
708

709
void show_interdiff(const struct object_id *oid1, const struct object_id *oid2,
710
		    int indent, struct diff_options *diffopt)
711
{
712
	struct diff_options opts;
713
	struct strbuf prefix = STRBUF_INIT;
714

715
	memcpy(&opts, diffopt, sizeof(opts));
716
	opts.output_format = DIFF_FORMAT_PATCH;
717
	opts.output_prefix = idiff_prefix_cb;
718
	strbuf_addchars(&prefix, ' ', indent);
719
	opts.output_prefix_data = &prefix;
720
	diff_setup_done(&opts);
721

722
	diff_tree_oid(oid1, oid2, "", &opts);
723
	diffcore_std(&opts);
724
	diff_flush(&opts);
725

726
	strbuf_release(&prefix);
727
}
728