Source

git / builtin-diff.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
/*
 * Builtin "git diff"
 *
 * Copyright (c) 2006 Junio C Hamano
 */
#include "cache.h"
#include "color.h"
#include "commit.h"
#include "blob.h"
#include "tag.h"
#include "diff.h"
#include "diffcore.h"
#include "revision.h"
#include "log-tree.h"
#include "builtin.h"

struct blobinfo {
	unsigned char sha1[20];
	const char *name;
	unsigned mode;
};

static const char builtin_diff_usage[] =
"git diff <options> <rev>{0,2} -- <path>*";

static void stuff_change(struct diff_options *opt,
			 unsigned old_mode, unsigned new_mode,
			 const unsigned char *old_sha1,
			 const unsigned char *new_sha1,
			 const char *old_name,
			 const char *new_name)
{
	struct diff_filespec *one, *two;

	if (!is_null_sha1(old_sha1) && !is_null_sha1(new_sha1) &&
	    !hashcmp(old_sha1, new_sha1) && (old_mode == new_mode))
		return;

	if (DIFF_OPT_TST(opt, REVERSE_DIFF)) {
		unsigned tmp;
		const unsigned char *tmp_u;
		const char *tmp_c;
		tmp = old_mode; old_mode = new_mode; new_mode = tmp;
		tmp_u = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_u;
		tmp_c = old_name; old_name = new_name; new_name = tmp_c;
	}

	if (opt->prefix &&
	    (strncmp(old_name, opt->prefix, opt->prefix_length) ||
	     strncmp(new_name, opt->prefix, opt->prefix_length)))
		return;

	one = alloc_filespec(old_name);
	two = alloc_filespec(new_name);
	fill_filespec(one, old_sha1, old_mode);
	fill_filespec(two, new_sha1, new_mode);

	diff_queue(&diff_queued_diff, one, two);
}

static int builtin_diff_b_f(struct rev_info *revs,
			    int argc, const char **argv,
			    struct blobinfo *blob,
			    const char *path)
{
	/* Blob vs file in the working tree*/
	struct stat st;

	if (argc > 1)
		usage(builtin_diff_usage);

	if (lstat(path, &st))
		die("'%s': %s", path, strerror(errno));
	if (!(S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)))
		die("'%s': not a regular file or symlink", path);

	if (blob[0].mode == S_IFINVALID)
		blob[0].mode = canon_mode(st.st_mode);

	stuff_change(&revs->diffopt,
		     blob[0].mode, canon_mode(st.st_mode),
		     blob[0].sha1, null_sha1,
		     path, path);
	diffcore_std(&revs->diffopt);
	diff_flush(&revs->diffopt);
	return 0;
}

static int builtin_diff_blobs(struct rev_info *revs,
			      int argc, const char **argv,
			      struct blobinfo *blob)
{
	unsigned mode = canon_mode(S_IFREG | 0644);

	if (argc > 1)
		usage(builtin_diff_usage);

	if (blob[0].mode == S_IFINVALID)
		blob[0].mode = mode;

	if (blob[1].mode == S_IFINVALID)
		blob[1].mode = mode;

	stuff_change(&revs->diffopt,
		     blob[0].mode, blob[1].mode,
		     blob[0].sha1, blob[1].sha1,
		     blob[0].name, blob[1].name);
	diffcore_std(&revs->diffopt);
	diff_flush(&revs->diffopt);
	return 0;
}

static int builtin_diff_index(struct rev_info *revs,
			      int argc, const char **argv)
{
	int cached = 0;
	while (1 < argc) {
		const char *arg = argv[1];
		if (!strcmp(arg, "--cached"))
			cached = 1;
		else
			usage(builtin_diff_usage);
		argv++; argc--;
	}
	if (!cached)
		setup_work_tree();
	/*
	 * Make sure there is one revision (i.e. pending object),
	 * and there is no revision filtering parameters.
	 */
	if (revs->pending.nr != 1 ||
	    revs->max_count != -1 || revs->min_age != -1 ||
	    revs->max_age != -1)
		usage(builtin_diff_usage);
	if (read_cache() < 0) {
		perror("read_cache");
		return -1;
	}
	return run_diff_index(revs, cached);
}

static int builtin_diff_tree(struct rev_info *revs,
			     int argc, const char **argv,
			     struct object_array_entry *ent)
{
	const unsigned char *(sha1[2]);
	int swap = 0;

	if (argc > 1)
		usage(builtin_diff_usage);

	/* We saw two trees, ent[0] and ent[1].
	 * if ent[1] is uninteresting, they are swapped
	 */
	if (ent[1].item->flags & UNINTERESTING)
		swap = 1;
	sha1[swap] = ent[0].item->sha1;
	sha1[1-swap] = ent[1].item->sha1;
	diff_tree_sha1(sha1[0], sha1[1], "", &revs->diffopt);
	log_tree_diff_flush(revs);
	return 0;
}

static int builtin_diff_combined(struct rev_info *revs,
				 int argc, const char **argv,
				 struct object_array_entry *ent,
				 int ents)
{
	const unsigned char (*parent)[20];
	int i;

	if (argc > 1)
		usage(builtin_diff_usage);

	if (!revs->dense_combined_merges && !revs->combine_merges)
		revs->dense_combined_merges = revs->combine_merges = 1;
	parent = xmalloc(ents * sizeof(*parent));
	for (i = 0; i < ents; i++)
		hashcpy((unsigned char *)(parent + i), ent[i].item->sha1);
	diff_tree_combined(parent[0], parent + 1, ents - 1,
			   revs->dense_combined_merges, revs);
	return 0;
}

static void refresh_index_quietly(void)
{
	struct lock_file *lock_file;
	int fd;

	lock_file = xcalloc(1, sizeof(struct lock_file));
	fd = hold_locked_index(lock_file, 0);
	if (fd < 0)
		return;
	discard_cache();
	read_cache();
	refresh_cache(REFRESH_QUIET|REFRESH_UNMERGED);

	if (active_cache_changed &&
	    !write_cache(fd, active_cache, active_nr))
		commit_locked_index(lock_file);

	rollback_lock_file(lock_file);
}

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

	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], "-q"))
			options |= DIFF_SILENT_ON_REMOVED;
		else
			return error("invalid option: %s", argv[1]);
		argv++; argc--;
	}

	/*
	 * "diff --base" should not combine merges because it was not
	 * asked to.  "diff -c" should not densify (if the user wants
	 * dense one, --cc can be explicitly asked for, or just rely
	 * on the default).
	 */
	if (revs->max_count == -1 && !revs->combine_merges &&
	    (revs->diffopt.output_format & DIFF_FORMAT_PATCH))
		revs->combine_merges = revs->dense_combined_merges = 1;

	setup_work_tree();
	if (read_cache() < 0) {
		perror("read_cache");
		return -1;
	}
	result = run_diff_files(revs, options);
	return diff_result_code(&revs->diffopt, result);
}

int cmd_diff(int argc, const char **argv, const char *prefix)
{
	int i;
	struct rev_info rev;
	struct object_array_entry ent[100];
	int ents = 0, blobs = 0, paths = 0;
	const char *path = NULL;
	struct blobinfo blob[2];
	int nongit;
	int result = 0;

	/*
	 * We could get N tree-ish in the rev.pending_objects list.
	 * Also there could be M blobs there, and P pathspecs.
	 *
	 * N=0, M=0:
	 *	cache vs files (diff-files)
	 * N=0, M=2:
	 *      compare two random blobs.  P must be zero.
	 * N=0, M=1, P=1:
	 *	compare a blob with a working tree file.
	 *
	 * N=1, M=0:
	 *      tree vs cache (diff-index --cached)
	 *
	 * N=2, M=0:
	 *      tree vs tree (diff-tree)
	 *
	 * N=0, M=0, P=2:
	 *      compare two filesystem entities (aka --no-index).
	 *
	 * Other cases are errors.
	 */

	prefix = setup_git_directory_gently(&nongit);
	git_config(git_diff_ui_config, NULL);

	if (diff_use_color_default == -1)
		diff_use_color_default = git_use_color_default;

	init_revisions(&rev, prefix);

	/* If this is a no-index diff, just run it and exit there. */
	diff_no_index(&rev, argc, argv, nongit, prefix);

	/* Otherwise, we are doing the usual "git" diff */
	rev.diffopt.skip_stat_unmatch = !!diff_auto_refresh_index;

	/* Default to let external be used */
	DIFF_OPT_SET(&rev.diffopt, ALLOW_EXTERNAL);

	if (nongit)
		die("Not a git repository");
	argc = setup_revisions(argc, argv, &rev, NULL);
	if (!rev.diffopt.output_format) {
		rev.diffopt.output_format = DIFF_FORMAT_PATCH;
		if (diff_setup_done(&rev.diffopt) < 0)
			die("diff_setup_done failed");
	}

	DIFF_OPT_SET(&rev.diffopt, RECURSIVE);

	/*
	 * If the user asked for our exit code then don't start a
	 * pager or we would end up reporting its exit code instead.
	 */
	if (!DIFF_OPT_TST(&rev.diffopt, EXIT_WITH_STATUS) &&
	    check_pager_config("diff") != 0)
		setup_pager();

	/*
	 * Do we have --cached and not have a pending object, then
	 * default to HEAD by hand.  Eek.
	 */
	if (!rev.pending.nr) {
		int i;
		for (i = 1; i < argc; i++) {
			const char *arg = argv[i];
			if (!strcmp(arg, "--"))
				break;
			else if (!strcmp(arg, "--cached")) {
				add_head_to_pending(&rev);
				if (!rev.pending.nr)
					die("No HEAD commit to compare with (yet)");
				break;
			}
		}
	}

	for (i = 0; i < rev.pending.nr; i++) {
		struct object_array_entry *list = rev.pending.objects+i;
		struct object *obj = list->item;
		const char *name = list->name;
		int flags = (obj->flags & UNINTERESTING);
		if (!obj->parsed)
			obj = parse_object(obj->sha1);
		obj = deref_tag(obj, NULL, 0);
		if (!obj)
			die("invalid object '%s' given.", name);
		if (obj->type == OBJ_COMMIT)
			obj = &((struct commit *)obj)->tree->object;
		if (obj->type == OBJ_TREE) {
			if (ARRAY_SIZE(ent) <= ents)
				die("more than %d trees given: '%s'",
				    (int) ARRAY_SIZE(ent), name);
			obj->flags |= flags;
			ent[ents].item = obj;
			ent[ents].name = name;
			ents++;
			continue;
		}
		if (obj->type == OBJ_BLOB) {
			if (2 <= blobs)
				die("more than two blobs given: '%s'", name);
			hashcpy(blob[blobs].sha1, obj->sha1);
			blob[blobs].name = name;
			blob[blobs].mode = list->mode;
			blobs++;
			continue;

		}
		die("unhandled object '%s' given.", name);
	}
	if (rev.prune_data) {
		const char **pathspec = rev.prune_data;
		while (*pathspec) {
			if (!path)
				path = *pathspec;
			paths++;
			pathspec++;
		}
	}

	/*
	 * Now, do the arguments look reasonable?
	 */
	if (!ents) {
		switch (blobs) {
		case 0:
			result = builtin_diff_files(&rev, argc, argv);
			break;
		case 1:
			if (paths != 1)
				usage(builtin_diff_usage);
			result = builtin_diff_b_f(&rev, argc, argv, blob, path);
			break;
		case 2:
			if (paths)
				usage(builtin_diff_usage);
			result = builtin_diff_blobs(&rev, argc, argv, blob);
			break;
		default:
			usage(builtin_diff_usage);
		}
	}
	else if (blobs)
		usage(builtin_diff_usage);
	else if (ents == 1)
		result = builtin_diff_index(&rev, argc, argv);
	else if (ents == 2)
		result = builtin_diff_tree(&rev, argc, argv, ent);
	else if ((ents == 3) && (ent[0].item->flags & UNINTERESTING)) {
		/* diff A...B where there is one sane merge base between
		 * A and B.  We have ent[0] == merge-base, ent[1] == A,
		 * and ent[2] == B.  Show diff between the base and B.
		 */
		ent[1] = ent[2];
		result = builtin_diff_tree(&rev, argc, argv, ent);
	}
	else
		result = builtin_diff_combined(&rev, argc, argv,
					     ent, ents);
	result = diff_result_code(&rev.diffopt, result);
	if (1 < rev.diffopt.skip_stat_unmatch)
		refresh_index_quietly();
	return result;
}
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.