Source

git / diff-lib.c

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
/*
 * Copyright (C) 2005 Junio C Hamano
 */
#include "cache.h"
#include "quote.h"
#include "commit.h"
#include "diff.h"
#include "diffcore.h"
#include "revision.h"
#include "cache-tree.h"
#include "path-list.h"
#include "unpack-trees.h"
#include "refs.h"

/*
 * diff-files
 */

static int read_directory(const char *path, struct path_list *list)
{
	DIR *dir;
	struct dirent *e;

	if (!(dir = opendir(path)))
		return error("Could not open directory %s", path);

	while ((e = readdir(dir)))
		if (strcmp(".", e->d_name) && strcmp("..", e->d_name))
			path_list_insert(e->d_name, list);

	closedir(dir);
	return 0;
}

static int get_mode(const char *path, int *mode)
{
	struct stat st;

	if (!path || !strcmp(path, "/dev/null"))
		*mode = 0;
	else if (!strcmp(path, "-"))
		*mode = create_ce_mode(0666);
	else if (stat(path, &st))
		return error("Could not access '%s'", path);
	else
		*mode = st.st_mode;
	return 0;
}

static int queue_diff(struct diff_options *o,
		const char *name1, const char *name2)
{
	int mode1 = 0, mode2 = 0;

	if (get_mode(name1, &mode1) || get_mode(name2, &mode2))
		return -1;

	if (mode1 && mode2 && S_ISDIR(mode1) != S_ISDIR(mode2))
		return error("file/directory conflict: %s, %s", name1, name2);

	if (S_ISDIR(mode1) || S_ISDIR(mode2)) {
		char buffer1[PATH_MAX], buffer2[PATH_MAX];
		struct path_list p1 = {NULL, 0, 0, 1}, p2 = {NULL, 0, 0, 1};
		int len1 = 0, len2 = 0, i1, i2, ret = 0;

		if (name1 && read_directory(name1, &p1))
			return -1;
		if (name2 && read_directory(name2, &p2)) {
			path_list_clear(&p1, 0);
			return -1;
		}

		if (name1) {
			len1 = strlen(name1);
			if (len1 > 0 && name1[len1 - 1] == '/')
				len1--;
			memcpy(buffer1, name1, len1);
			buffer1[len1++] = '/';
		}

		if (name2) {
			len2 = strlen(name2);
			if (len2 > 0 && name2[len2 - 1] == '/')
				len2--;
			memcpy(buffer2, name2, len2);
			buffer2[len2++] = '/';
		}

		for (i1 = i2 = 0; !ret && (i1 < p1.nr || i2 < p2.nr); ) {
			const char *n1, *n2;
			int comp;

			if (i1 == p1.nr)
				comp = 1;
			else if (i2 == p2.nr)
				comp = -1;
			else
				comp = strcmp(p1.items[i1].path,
					p2.items[i2].path);

			if (comp > 0)
				n1 = NULL;
			else {
				n1 = buffer1;
				strncpy(buffer1 + len1, p1.items[i1++].path,
						PATH_MAX - len1);
			}

			if (comp < 0)
				n2 = NULL;
			else {
				n2 = buffer2;
				strncpy(buffer2 + len2, p2.items[i2++].path,
						PATH_MAX - len2);
			}

			ret = queue_diff(o, n1, n2);
		}
		path_list_clear(&p1, 0);
		path_list_clear(&p2, 0);

		return ret;
	} else {
		struct diff_filespec *d1, *d2;

		if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
			unsigned tmp;
			const char *tmp_c;
			tmp = mode1; mode1 = mode2; mode2 = tmp;
			tmp_c = name1; name1 = name2; name2 = tmp_c;
		}

		if (!name1)
			name1 = "/dev/null";
		if (!name2)
			name2 = "/dev/null";
		d1 = alloc_filespec(name1);
		d2 = alloc_filespec(name2);
		fill_filespec(d1, null_sha1, mode1);
		fill_filespec(d2, null_sha1, mode2);

		diff_queue(&diff_queued_diff, d1, d2);
		return 0;
	}
}

/*
 * Does the path name a blob in the working tree, or a directory
 * in the working tree?
 */
static int is_in_index(const char *path)
{
	int len, pos;
	struct cache_entry *ce;

	len = strlen(path);
	while (path[len-1] == '/')
		len--;
	if (!len)
		return 1; /* "." */
	pos = cache_name_pos(path, len);
	if (0 <= pos)
		return 1;
	pos = -1 - pos;
	while (pos < active_nr) {
		ce = active_cache[pos++];
		if (ce_namelen(ce) <= len ||
		    strncmp(ce->name, path, len) ||
		    (ce->name[len] > '/'))
			break; /* path cannot be a prefix */
		if (ce->name[len] == '/')
			return 1;
	}
	return 0;
}

static int handle_diff_files_args(struct rev_info *revs,
				  int argc, const char **argv,
				  unsigned int *options)
{
	*options = 0;

	/* revs->max_count == -2 means --no-index */
	while (1 < argc && argv[1][0] == '-') {
		if (!strcmp(argv[1], "--base"))
			revs->max_count = 1;
		else if (!strcmp(argv[1], "--ours"))
			revs->max_count = 2;
		else if (!strcmp(argv[1], "--theirs"))
			revs->max_count = 3;
		else if (!strcmp(argv[1], "-n") ||
				!strcmp(argv[1], "--no-index")) {
			revs->max_count = -2;
			DIFF_OPT_SET(&revs->diffopt, EXIT_WITH_STATUS);
			DIFF_OPT_SET(&revs->diffopt, NO_INDEX);
		}
		else if (!strcmp(argv[1], "-q"))
			*options |= DIFF_SILENT_ON_REMOVED;
		else
			return error("invalid option: %s", argv[1]);
		argv++; argc--;
	}

	if (revs->max_count == -1 && revs->diffopt.nr_paths == 2) {
		/*
		 * If two files are specified, and at least one is untracked,
		 * default to no-index.
		 */
		read_cache();
		if (!is_in_index(revs->diffopt.paths[0]) ||
					!is_in_index(revs->diffopt.paths[1])) {
			revs->max_count = -2;
			DIFF_OPT_SET(&revs->diffopt, NO_INDEX);
		}
	}

	/*
	 * Make sure there are NO revision (i.e. pending object) parameter,
	 * rev.max_count is reasonable (0 <= n <= 3),
	 * there is no other revision filtering parameters.
	 */
	if (revs->pending.nr || revs->max_count > 3 ||
	    revs->min_age != -1 || revs->max_age != -1)
		return error("no revision allowed with diff-files");

	if (revs->max_count == -1 &&
	    (revs->diffopt.output_format & DIFF_FORMAT_PATCH))
		revs->combine_merges = revs->dense_combined_merges = 1;

	return 0;
}

static int is_outside_repo(const char *path, int nongit, const char *prefix)
{
	int i;
	if (nongit || !strcmp(path, "-") || is_absolute_path(path))
		return 1;
	if (prefixcmp(path, "../"))
		return 0;
	if (!prefix)
		return 1;
	for (i = strlen(prefix); !prefixcmp(path, "../"); ) {
		while (i > 0 && prefix[i - 1] != '/')
			i--;
		if (--i < 0)
			return 1;
		path += 3;
	}
	return 0;
}

int setup_diff_no_index(struct rev_info *revs,
		int argc, const char ** argv, int nongit, const char *prefix)
{
	int i;
	for (i = 1; i < argc; i++)
		if (argv[i][0] != '-' || argv[i][1] == '\0')
			break;
		else if (!strcmp(argv[i], "--")) {
			i++;
			break;
		} else if (i < argc - 3 && !strcmp(argv[i], "--no-index")) {
			i = argc - 3;
			DIFF_OPT_SET(&revs->diffopt, EXIT_WITH_STATUS);
			break;
		}
	if (argc != i + 2 || (!is_outside_repo(argv[i + 1], nongit, prefix) &&
				!is_outside_repo(argv[i], nongit, prefix)))
		return -1;

	diff_setup(&revs->diffopt);
	for (i = 1; i < argc - 2; )
		if (!strcmp(argv[i], "--no-index"))
			i++;
		else {
			int j = diff_opt_parse(&revs->diffopt,
					argv + i, argc - i);
			if (!j)
				die("invalid diff option/value: %s", argv[i]);
			i += j;
		}

	if (prefix) {
		int len = strlen(prefix);

		revs->diffopt.paths = xcalloc(2, sizeof(char*));
		for (i = 0; i < 2; i++) {
			const char *p = argv[argc - 2 + i];
			/*
			 * stdin should be spelled as '-'; if you have
			 * path that is '-', spell it as ./-.
			 */
			p = (strcmp(p, "-")
			     ? xstrdup(prefix_filename(prefix, len, p))
			     : p);
			revs->diffopt.paths[i] = p;
		}
	}
	else
		revs->diffopt.paths = argv + argc - 2;
	revs->diffopt.nr_paths = 2;
	DIFF_OPT_SET(&revs->diffopt, NO_INDEX);
	revs->max_count = -2;
	if (diff_setup_done(&revs->diffopt) < 0)
		die("diff_setup_done failed");
	return 0;
}

int run_diff_files_cmd(struct rev_info *revs, int argc, const char **argv)
{
	unsigned int options;

	if (handle_diff_files_args(revs, argc, argv, &options))
		return -1;

	if (DIFF_OPT_TST(&revs->diffopt, NO_INDEX)) {
		if (revs->diffopt.nr_paths != 2)
			return error("need two files/directories with --no-index");
		if (queue_diff(&revs->diffopt, revs->diffopt.paths[0],
				revs->diffopt.paths[1]))
			return -1;
		diffcore_std(&revs->diffopt);
		diff_flush(&revs->diffopt);
		/*
		 * The return code for --no-index imitates diff(1):
		 * 0 = no changes, 1 = changes, else error
		 */
		return revs->diffopt.found_changes;
	}

	if (read_cache() < 0) {
		perror("read_cache");
		return -1;
	}
	return run_diff_files(revs, options);
}
/*
 * See if work tree has an entity that can be staged.  Return 0 if so,
 * return 1 if not and return -1 if error.
 */
static int check_work_tree_entity(const struct cache_entry *ce, struct stat *st, char *symcache)
{
	if (lstat(ce->name, st) < 0) {
		if (errno != ENOENT && errno != ENOTDIR)
			return -1;
		return 1;
	}
	if (has_symlink_leading_path(ce->name, symcache))
		return 1;
	if (S_ISDIR(st->st_mode)) {
		unsigned char sub[20];
		if (resolve_gitlink_ref(ce->name, "HEAD", sub))
			return 1;
	}
	return 0;
}

int run_diff_files(struct rev_info *revs, unsigned int option)
{
	int entries, i;
	int diff_unmerged_stage = revs->max_count;
	int silent_on_removed = option & DIFF_SILENT_ON_REMOVED;
	unsigned ce_option = ((option & DIFF_RACY_IS_MODIFIED)
			      ? CE_MATCH_RACY_IS_DIRTY : 0);
	char symcache[PATH_MAX];

	if (diff_unmerged_stage < 0)
		diff_unmerged_stage = 2;
	entries = active_nr;
	symcache[0] = '\0';
	for (i = 0; i < entries; i++) {
		struct stat st;
		unsigned int oldmode, newmode;
		struct cache_entry *ce = active_cache[i];
		int changed;

		if (DIFF_OPT_TST(&revs->diffopt, QUIET) &&
			DIFF_OPT_TST(&revs->diffopt, HAS_CHANGES))
			break;

		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';
			hashclr(dpath->sha1);
			memset(&(dpath->parent[0]), 0,
			       sizeof(struct combine_diff_parent)*5);

			changed = check_work_tree_entity(ce, &st, symcache);
			if (!changed)
				dpath->mode = ce_mode_from_stat(ce, st.st_mode);
			else {
				if (changed < 0) {
					perror(ce->name);
					continue;
				}
				if (silent_on_removed)
					continue;
			}

			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 = nce->ce_mode;
					num_compare_stages++;
					hashcpy(dpath->parent[stage-2].sha1, nce->sha1);
					dpath->parent[stage-2].mode = ce_mode_from_stat(nce, 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, 0, null_sha1);
			if (ce_stage(ce) != diff_unmerged_stage)
				continue;
		}

		if (ce_uptodate(ce))
			continue;

		changed = check_work_tree_entity(ce, &st, symcache);
		if (changed) {
			if (changed < 0) {
				perror(ce->name);
				continue;
			}
			if (silent_on_removed)
				continue;
			diff_addremove(&revs->diffopt, '-', ce->ce_mode,
				       ce->sha1, ce->name, NULL);
			continue;
		}
		changed = ce_match_stat(ce, &st, ce_option);
		if (!changed && !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
			continue;
		oldmode = ce->ce_mode;
		newmode = ce_mode_from_stat(ce, st.st_mode);
		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
 */

struct oneway_unpack_data {
	struct rev_info *revs;
	char symcache[PATH_MAX];
};

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

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

	if (!cached) {
		int changed;
		struct stat st;
		changed = check_work_tree_entity(ce, &st, cbdata->symcache);
		if (changed < 0)
			return -1;
		else if (changed) {
			if (match_missing) {
				*sha1p = sha1;
				*modep = mode;
				return 0;
			}
			return -1;
		}
		changed = ce_match_stat(ce, &st, 0);
		if (changed) {
			mode = ce_mode_from_stat(ce, st.st_mode);
			sha1 = null_sha1;
		}
	}

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

static void show_new_file(struct oneway_unpack_data *cbdata,
			  struct cache_entry *new,
			  int cached, int match_missing)
{
	const unsigned char *sha1;
	unsigned int mode;
	struct rev_info *revs = cbdata->revs;

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

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

static int show_modified(struct oneway_unpack_data *cbdata,
			 struct cache_entry *old,
			 struct cache_entry *new,
			 int report_missing,
			 int cached, int match_missing)
{
	unsigned int mode, oldmode;
	const unsigned char *sha1;
	struct rev_info *revs = cbdata->revs;

	if (get_stat_data(new, &sha1, &mode, cached, match_missing, cbdata) < 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 = 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 = new->ce_mode;
		hashcpy(p->parent[0].sha1, new->sha1);
		p->parent[1].status = DIFF_STATUS_MODIFIED;
		p->parent[1].mode = 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) &&
	    !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
		return 0;

	diff_change(&revs->diffopt, oldmode, mode,
		    old->sha1, sha1, old->name, NULL);
	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 |= CE_STAGEMASK;
	}
}

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

	/*
	 * Backward compatibility wart - "diff-index -m" does
	 * not mean "do not ignore merges", but "match_missing".
	 *
	 * But with the revision flag parsing, that's found in
	 * "!revs->ignore_merges".
	 */
	cached = o->index_only;
	match_missing = !revs->ignore_merges;

	if (cached && idx && ce_stage(idx)) {
		if (tree)
			diff_unmerge(&revs->diffopt, idx->name, idx->ce_mode, idx->sha1);
		return;
	}

	/*
	 * Something added to the tree?
	 */
	if (!tree) {
		show_new_file(cbdata, idx, cached, match_missing);
		return;
	}

	/*
	 * Something removed from the tree?
	 */
	if (!idx) {
		diff_index_show_file(revs, "-", tree, tree->sha1, tree->ce_mode);
		return;
	}

	/* Show difference between old and new */
	show_modified(cbdata, tree, idx, 1, cached, match_missing);
}

static inline void skip_same_name(struct cache_entry *ce, struct unpack_trees_options *o)
{
	int len = ce_namelen(ce);
	const struct index_state *index = o->src_index;

	while (o->pos < index->cache_nr) {
		struct cache_entry *next = index->cache[o->pos];
		if (len != ce_namelen(next))
			break;
		if (memcmp(ce->name, next->name, len))
			break;
		o->pos++;
	}
}

/*
 * The unpack_trees() interface is designed for merging, so
 * the different source entries are designed primarily for
 * the source trees, with the old index being really mainly
 * used for being replaced by the result.
 *
 * For diffing, the index is more important, and we only have a
 * single tree.
 *
 * We're supposed to return how many index entries we want to skip.
 *
 * This wrapper makes it all more readable, and takes care of all
 * the fairly complex unpack_trees() semantic requirements, including
 * the skipping, the path matching, the type conflict cases etc.
 */
static int oneway_diff(struct cache_entry **src, struct unpack_trees_options *o)
{
	struct cache_entry *idx = src[0];
	struct cache_entry *tree = src[1];
	struct oneway_unpack_data *cbdata = o->unpack_data;
	struct rev_info *revs = cbdata->revs;

	if (idx && ce_stage(idx))
		skip_same_name(idx, o);

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

	if (ce_path_match(idx ? idx : tree, revs->prune_data))
		do_oneway_diff(o, idx, tree);

	return 0;
}

int run_diff_index(struct rev_info *revs, int cached)
{
	struct object *ent;
	struct tree *tree;
	const char *tree_name;
	struct unpack_trees_options opts;
	struct tree_desc t;
	struct oneway_unpack_data unpack_cb;

	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);

	unpack_cb.revs = revs;
	unpack_cb.symcache[0] = '\0';
	memset(&opts, 0, sizeof(opts));
	opts.head_idx = 1;
	opts.index_only = cached;
	opts.merge = 1;
	opts.fn = oneway_diff;
	opts.unpack_data = &unpack_cb;
	opts.src_index = &the_index;
	opts.dst_index = NULL;

	init_tree_desc(&t, tree->buffer, tree->size);
	if (unpack_trees(1, &t, &opts))
		exit(128);

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

int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
{
	struct tree *tree;
	struct rev_info revs;
	int i;
	struct cache_entry **dst;
	struct cache_entry *last = NULL;
	struct unpack_trees_options opts;
	struct tree_desc t;
	struct oneway_unpack_data unpack_cb;

	/*
	 * This is used by git-blame to run diff-cache internally;
	 * it potentially needs to repeatedly run this, so we will
	 * start by removing the higher order entries the last round
	 * left behind.
	 */
	dst = active_cache;
	for (i = 0; i < active_nr; i++) {
		struct cache_entry *ce = active_cache[i];
		if (ce_stage(ce)) {
			if (last && !strcmp(ce->name, last->name))
				continue;
			cache_tree_invalidate_path(active_cache_tree,
						   ce->name);
			last = ce;
			ce->ce_flags |= CE_REMOVE;
		}
		*dst++ = ce;
	}
	active_nr = dst - active_cache;

	init_revisions(&revs, NULL);
	revs.prune_data = opt->paths;
	tree = parse_tree_indirect(tree_sha1);
	if (!tree)
		die("bad tree object %s", sha1_to_hex(tree_sha1));

	unpack_cb.revs = &revs;
	unpack_cb.symcache[0] = '\0';
	memset(&opts, 0, sizeof(opts));
	opts.head_idx = 1;
	opts.index_only = 1;
	opts.merge = 1;
	opts.fn = oneway_diff;
	opts.unpack_data = &unpack_cb;
	opts.src_index = &the_index;
	opts.dst_index = &the_index;

	init_tree_desc(&t, tree->buffer, tree->size);
	if (unpack_trees(1, &t, &opts))
		exit(128);
	return 0;
}
Tip: Filter by directory path e.g. /media app.js to search for public/media/app.js.
Tip: Use camelCasing e.g. ProjME to search for ProjectModifiedEvent.java.
Tip: Filter by extension type e.g. /repo .js to search for all .js files in the /repo directory.
Tip: Separate your search with spaces e.g. /ssh pom.xml to search for src/ssh/pom.xml.
Tip: Use ↑ and ↓ arrow keys to navigate and return to view the file.
Tip: You can also navigate files with Ctrl+j (next) and Ctrl+k (previous) and view the file with Ctrl+o.
Tip: You can also navigate files with Alt+j (next) and Alt+k (previous) and view the file with Alt+o.