Merge branch 'ah/doc-gitattributes-empty-index' into maint
[git/git.git] / builtin / diff.c
CommitLineData
65056021
JH
1/*
2 * Builtin "git diff"
3 *
4 * Copyright (c) 2006 Junio C Hamano
5 */
6#include "cache.h"
697cc8ef 7#include "lockfile.h"
6b2f2d98 8#include "color.h"
65056021
JH
9#include "commit.h"
10#include "blob.h"
11#include "tag.h"
12#include "diff.h"
13#include "diffcore.h"
14#include "revision.h"
15#include "log-tree.h"
16#include "builtin.h"
302ad7a9 17#include "submodule.h"
0041f09d 18#include "sha1-array.h"
65056021 19
470faf96
TG
20#define DIFF_NO_INDEX_EXPLICIT 1
21#define DIFF_NO_INDEX_IMPLICIT 2
22
65056021 23static const char builtin_diff_usage[] =
9edb8a0f 24"git diff [<options>] [<commit> [<commit>]] [--] [<path>...]";
65056021 25
158b06ca
JK
26static const char *blob_path(struct object_array_entry *entry)
27{
28 return entry->path ? entry->path : entry->name;
29}
30
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31static void stuff_change(struct diff_options *opt,
32 unsigned old_mode, unsigned new_mode,
9c4b0f66 33 const struct object_id *old_oid,
34 const struct object_id *new_oid,
35 int old_oid_valid,
36 int new_oid_valid,
d04ec74b
JK
37 const char *old_path,
38 const char *new_path)
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39{
40 struct diff_filespec *one, *two;
41
9c4b0f66 42 if (!is_null_oid(old_oid) && !is_null_oid(new_oid) &&
43 !oidcmp(old_oid, new_oid) && (old_mode == new_mode))
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44 return;
45
8f67f8ae 46 if (DIFF_OPT_TST(opt, REVERSE_DIFF)) {
35d803bc 47 SWAP(old_mode, new_mode);
9c4b0f66 48 SWAP(old_oid, new_oid);
d04ec74b 49 SWAP(old_path, new_path);
65056021 50 }
cd676a51
JH
51
52 if (opt->prefix &&
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53 (strncmp(old_path, opt->prefix, opt->prefix_length) ||
54 strncmp(new_path, opt->prefix, opt->prefix_length)))
cd676a51
JH
55 return;
56
d04ec74b
JK
57 one = alloc_filespec(old_path);
58 two = alloc_filespec(new_path);
9c4b0f66 59 fill_filespec(one, old_oid->hash, old_oid_valid, old_mode);
60 fill_filespec(two, new_oid->hash, new_oid_valid, new_mode);
65056021 61
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62 diff_queue(&diff_queued_diff, one, two);
63}
64
65static int builtin_diff_b_f(struct rev_info *revs,
66 int argc, const char **argv,
42f5ba5b 67 struct object_array_entry **blob)
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68{
69 /* Blob vs file in the working tree*/
70 struct stat st;
887c6c18 71 const char *path;
65056021 72
a610786f
TH
73 if (argc > 1)
74 usage(builtin_diff_usage);
75
887c6c18
NTND
76 GUARD_PATHSPEC(&revs->prune_data, PATHSPEC_FROMTOP | PATHSPEC_LITERAL);
77 path = revs->prune_data.items[0].match;
78
65056021 79 if (lstat(path, &st))
54214529 80 die_errno(_("failed to stat '%s'"), path);
65056021 81 if (!(S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)))
54214529 82 die(_("'%s': not a regular file or symlink"), path);
01618a3a 83
a5a818ee
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84 diff_set_mnemonic_prefix(&revs->diffopt, "o/", "w/");
85
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86 if (blob[0]->mode == S_IFINVALID)
87 blob[0]->mode = canon_mode(st.st_mode);
01618a3a 88
65056021 89 stuff_change(&revs->diffopt,
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JK
90 blob[0]->mode, canon_mode(st.st_mode),
91 &blob[0]->item->oid, &null_oid,
e5450100 92 1, 0,
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93 blob[0]->path ? blob[0]->path : path,
94 path);
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95 diffcore_std(&revs->diffopt);
96 diff_flush(&revs->diffopt);
97 return 0;
98}
99
100static int builtin_diff_blobs(struct rev_info *revs,
101 int argc, const char **argv,
42f5ba5b 102 struct object_array_entry **blob)
65056021 103{
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104 unsigned mode = canon_mode(S_IFREG | 0644);
105
a610786f
TH
106 if (argc > 1)
107 usage(builtin_diff_usage);
108
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JK
109 if (blob[0]->mode == S_IFINVALID)
110 blob[0]->mode = mode;
01618a3a 111
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112 if (blob[1]->mode == S_IFINVALID)
113 blob[1]->mode = mode;
01618a3a 114
65056021 115 stuff_change(&revs->diffopt,
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116 blob[0]->mode, blob[1]->mode,
117 &blob[0]->item->oid, &blob[1]->item->oid,
e5450100 118 1, 1,
158b06ca 119 blob_path(blob[0]), blob_path(blob[1]));
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120 diffcore_std(&revs->diffopt);
121 diff_flush(&revs->diffopt);
122 return 0;
123}
124
125static int builtin_diff_index(struct rev_info *revs,
126 int argc, const char **argv)
127{
128 int cached = 0;
129 while (1 < argc) {
130 const char *arg = argv[1];
2baf1850 131 if (!strcmp(arg, "--cached") || !strcmp(arg, "--staged"))
65056021 132 cached = 1;
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133 else
134 usage(builtin_diff_usage);
135 argv++; argc--;
136 }
137 /*
138 * Make sure there is one revision (i.e. pending object),
139 * and there is no revision filtering parameters.
140 */
1f1e895f 141 if (revs->pending.nr != 1 ||
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142 revs->max_count != -1 || revs->min_age != -1 ||
143 revs->max_age != -1)
144 usage(builtin_diff_usage);
7349afd2
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145 if (!cached) {
146 setup_work_tree();
5ab2a2da 147 if (read_cache_preload(&revs->diffopt.pathspec) < 0) {
7349afd2
KB
148 perror("read_cache_preload");
149 return -1;
150 }
151 } else if (read_cache() < 0) {
152 perror("read_cache");
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153 return -1;
154 }
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155 return run_diff_index(revs, cached);
156}
157
158static int builtin_diff_tree(struct rev_info *revs,
159 int argc, const char **argv,
91de344d
MH
160 struct object_array_entry *ent0,
161 struct object_array_entry *ent1)
65056021 162{
9c4b0f66 163 const struct object_id *(oid[2]);
1f1e895f 164 int swap = 0;
a610786f
TH
165
166 if (argc > 1)
167 usage(builtin_diff_usage);
0fe7c1de 168
91de344d
MH
169 /*
170 * We saw two trees, ent0 and ent1. If ent1 is uninteresting,
171 * swap them.
0fe7c1de 172 */
91de344d 173 if (ent1->item->flags & UNINTERESTING)
1f1e895f 174 swap = 1;
9c4b0f66 175 oid[swap] = &ent0->item->oid;
176 oid[1 - swap] = &ent1->item->oid;
177 diff_tree_sha1(oid[0]->hash, oid[1]->hash, "", &revs->diffopt);
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178 log_tree_diff_flush(revs);
179 return 0;
180}
181
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182static int builtin_diff_combined(struct rev_info *revs,
183 int argc, const char **argv,
1f1e895f 184 struct object_array_entry *ent,
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185 int ents)
186{
910650d2 187 struct oid_array parents = OID_ARRAY_INIT;
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188 int i;
189
a610786f
TH
190 if (argc > 1)
191 usage(builtin_diff_usage);
192
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193 if (!revs->dense_combined_merges && !revs->combine_merges)
194 revs->dense_combined_merges = revs->combine_merges = 1;
0041f09d 195 for (i = 1; i < ents; i++)
910650d2 196 oid_array_append(&parents, &ent[i].item->oid);
ed1c9977 197 diff_tree_combined(ent[0].item->oid.hash, &parents,
0fe7c1de 198 revs->dense_combined_merges, revs);
910650d2 199 oid_array_clear(&parents);
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200 return 0;
201}
202
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203static void refresh_index_quietly(void)
204{
205 struct lock_file *lock_file;
206 int fd;
207
208 lock_file = xcalloc(1, sizeof(struct lock_file));
209 fd = hold_locked_index(lock_file, 0);
210 if (fd < 0)
211 return;
212 discard_cache();
213 read_cache();
214 refresh_cache(REFRESH_QUIET|REFRESH_UNMERGED);
ccdc4ec3 215 update_index_if_able(&the_index, lock_file);
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216}
217
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218static int builtin_diff_files(struct rev_info *revs, int argc, const char **argv)
219{
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220 unsigned int options = 0;
221
222 while (1 < argc && argv[1][0] == '-') {
223 if (!strcmp(argv[1], "--base"))
224 revs->max_count = 1;
225 else if (!strcmp(argv[1], "--ours"))
226 revs->max_count = 2;
227 else if (!strcmp(argv[1], "--theirs"))
228 revs->max_count = 3;
229 else if (!strcmp(argv[1], "-q"))
230 options |= DIFF_SILENT_ON_REMOVED;
1c370ea4
MM
231 else if (!strcmp(argv[1], "-h"))
232 usage(builtin_diff_usage);
0569e9b8 233 else
54214529 234 return error(_("invalid option: %s"), argv[1]);
0569e9b8
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235 argv++; argc--;
236 }
237
903e09a3
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238 /*
239 * "diff --base" should not combine merges because it was not
240 * asked to. "diff -c" should not densify (if the user wants
241 * dense one, --cc can be explicitly asked for, or just rely
242 * on the default).
243 */
244 if (revs->max_count == -1 && !revs->combine_merges &&
0569e9b8
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245 (revs->diffopt.output_format & DIFF_FORMAT_PATCH))
246 revs->combine_merges = revs->dense_combined_merges = 1;
247
4f38f6b5 248 setup_work_tree();
5ab2a2da 249 if (read_cache_preload(&revs->diffopt.pathspec) < 0) {
671c9b7e 250 perror("read_cache_preload");
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251 return -1;
252 }
e7c3a59c 253 return run_diff_files(revs, options);
0569e9b8
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254}
255
a633fca0 256int cmd_diff(int argc, const char **argv, const char *prefix)
65056021 257{
1f1e895f 258 int i;
65056021 259 struct rev_info rev;
33055fa8
MH
260 struct object_array ent = OBJECT_ARRAY_INIT;
261 int blobs = 0, paths = 0;
42f5ba5b 262 struct object_array_entry *blob[2];
470faf96 263 int nongit = 0, no_index = 0;
41bbf9d5 264 int result = 0;
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265
266 /*
267 * We could get N tree-ish in the rev.pending_objects list.
268 * Also there could be M blobs there, and P pathspecs.
269 *
270 * N=0, M=0:
271 * cache vs files (diff-files)
272 * N=0, M=2:
273 * compare two random blobs. P must be zero.
274 * N=0, M=1, P=1:
275 * compare a blob with a working tree file.
276 *
277 * N=1, M=0:
278 * tree vs cache (diff-index --cached)
279 *
280 * N=2, M=0:
281 * tree vs tree (diff-tree)
282 *
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283 * N=0, M=0, P=2:
284 * compare two filesystem entities (aka --no-index).
285 *
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286 * Other cases are errors.
287 */
230f544e 288
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289 /* Were we asked to do --no-index explicitly? */
290 for (i = 1; i < argc; i++) {
291 if (!strcmp(argv[i], "--")) {
292 i++;
293 break;
294 }
295 if (!strcmp(argv[i], "--no-index"))
296 no_index = DIFF_NO_INDEX_EXPLICIT;
297 if (argv[i][0] != '-')
298 break;
299 }
300
28a4e580 301 prefix = setup_git_directory_gently(&nongit);
6df5762d 302
28a4e580 303 if (!no_index) {
475b362c
JK
304 /*
305 * Treat git diff with at least one path outside of the
306 * repo the same as if the command would have been executed
307 * outside of a git repository. In this case it behaves
308 * the same way as "git diff --no-index <a> <b>", which acts
309 * as a colourful "diff" replacement.
310 */
311 if (nongit || ((argc == i + 2) &&
312 (!path_inside_repo(prefix, argv[i]) ||
313 !path_inside_repo(prefix, argv[i + 1]))))
314 no_index = DIFF_NO_INDEX_IMPLICIT;
315 }
470faf96 316
6df5762d
TG
317 if (!no_index)
318 gitmodules_config();
5404c116 319 init_diff_ui_defaults();
ef90d6d4 320 git_config(git_diff_ui_config, NULL);
90a78b83 321 precompose_argv(argc, argv);
6b2f2d98 322
db6296a5 323 init_revisions(&rev, prefix);
0569e9b8 324
aad90e85
TG
325 if (no_index && argc != i + 2) {
326 if (no_index == DIFF_NO_INDEX_IMPLICIT) {
327 /*
328 * There was no --no-index and there were not two
329 * paths. It is possible that the user intended
330 * to do an inside-repository operation.
331 */
332 fprintf(stderr, "Not a git repository\n");
333 fprintf(stderr,
334 "To compare two paths outside a working tree:\n");
470faf96 335 }
aad90e85
TG
336 /* Give the usage message for non-repository usage and exit. */
337 usagef("git diff %s <path> <path>",
338 no_index == DIFF_NO_INDEX_EXPLICIT ?
339 "--no-index" : "[--no-index]");
340
341 }
342 if (no_index)
470faf96 343 /* If this is a no-index diff, just run it and exit there. */
e5f7a5d1 344 diff_no_index(&rev, argc, argv);
0569e9b8
JH
345
346 /* Otherwise, we are doing the usual "git" diff */
aecbf914 347 rev.diffopt.skip_stat_unmatch = !!diff_auto_refresh_index;
65056021 348
df44483a 349 /* Scale to real terminal size and respect statGraphWidth config */
af9fedc1 350 rev.diffopt.stat_width = -1;
df44483a 351 rev.diffopt.stat_graph_width = -1;
af9fedc1 352
5ec11af6 353 /* Default to let external and textconv be used */
61af494c 354 DIFF_OPT_SET(&rev.diffopt, ALLOW_EXTERNAL);
5ec11af6 355 DIFF_OPT_SET(&rev.diffopt, ALLOW_TEXTCONV);
61af494c 356
0569e9b8 357 if (nongit)
54214529 358 die(_("Not a git repository"));
0569e9b8 359 argc = setup_revisions(argc, argv, &rev, NULL);
047fbe90 360 if (!rev.diffopt.output_format) {
c9b5ef99 361 rev.diffopt.output_format = DIFF_FORMAT_PATCH;
28452655 362 diff_setup_done(&rev.diffopt);
047fbe90 363 }
61af494c 364
8f67f8ae 365 DIFF_OPT_SET(&rev.diffopt, RECURSIVE);
c9b5ef99 366
1af3d977 367 setup_diff_pager(&rev.diffopt);
89d07f75 368
0569e9b8
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369 /*
370 * Do we have --cached and not have a pending object, then
65056021
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371 * default to HEAD by hand. Eek.
372 */
1f1e895f 373 if (!rev.pending.nr) {
65056021
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374 int i;
375 for (i = 1; i < argc; i++) {
376 const char *arg = argv[i];
377 if (!strcmp(arg, "--"))
378 break;
2baf1850
DS
379 else if (!strcmp(arg, "--cached") ||
380 !strcmp(arg, "--staged")) {
3384a2df 381 add_head_to_pending(&rev);
a2b7a3b3
NTND
382 if (!rev.pending.nr) {
383 struct tree *tree;
cba595bd 384 tree = lookup_tree(EMPTY_TREE_SHA1_BIN);
a2b7a3b3
NTND
385 add_pending_object(&rev, &tree->object, "HEAD");
386 }
65056021
JH
387 break;
388 }
389 }
390 }
391
1f1e895f 392 for (i = 0; i < rev.pending.nr; i++) {
026f09e7
MH
393 struct object_array_entry *entry = &rev.pending.objects[i];
394 struct object *obj = entry->item;
395 const char *name = entry->name;
65056021
JH
396 int flags = (obj->flags & UNINTERESTING);
397 if (!obj->parsed)
ed1c9977 398 obj = parse_object(obj->oid.hash);
65056021
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399 obj = deref_tag(obj, NULL, 0);
400 if (!obj)
54214529 401 die(_("invalid object '%s' given."), name);
1974632c 402 if (obj->type == OBJ_COMMIT)
65056021 403 obj = &((struct commit *)obj)->tree->object;
5b1e14ea 404
1974632c 405 if (obj->type == OBJ_TREE) {
65056021 406 obj->flags |= flags;
33055fa8 407 add_object_array(obj, name, &ent);
5b1e14ea 408 } else if (obj->type == OBJ_BLOB) {
65056021 409 if (2 <= blobs)
54214529 410 die(_("more than two blobs given: '%s'"), name);
42f5ba5b 411 blob[blobs] = entry;
65056021 412 blobs++;
230f544e 413
5b1e14ea
MH
414 } else {
415 die(_("unhandled object '%s' given."), name);
65056021 416 }
65056021 417 }
887c6c18 418 if (rev.prune_data.nr)
afe069d1 419 paths += rev.prune_data.nr;
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420
421 /*
422 * Now, do the arguments look reasonable?
423 */
33055fa8 424 if (!ent.nr) {
65056021
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425 switch (blobs) {
426 case 0:
0569e9b8 427 result = builtin_diff_files(&rev, argc, argv);
65056021
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428 break;
429 case 1:
430 if (paths != 1)
431 usage(builtin_diff_usage);
887c6c18 432 result = builtin_diff_b_f(&rev, argc, argv, blob);
65056021
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433 break;
434 case 2:
0fe7c1de
JH
435 if (paths)
436 usage(builtin_diff_usage);
41bbf9d5 437 result = builtin_diff_blobs(&rev, argc, argv, blob);
65056021
JH
438 break;
439 default:
440 usage(builtin_diff_usage);
441 }
442 }
443 else if (blobs)
444 usage(builtin_diff_usage);
33055fa8 445 else if (ent.nr == 1)
41bbf9d5 446 result = builtin_diff_index(&rev, argc, argv);
33055fa8
MH
447 else if (ent.nr == 2)
448 result = builtin_diff_tree(&rev, argc, argv,
449 &ent.objects[0], &ent.objects[1]);
450 else if (ent.objects[0].item->flags & UNINTERESTING) {
c008c0ff
JH
451 /*
452 * diff A...B where there is at least one merge base
33055fa8
MH
453 * between A and B. We have ent.objects[0] ==
454 * merge-base, ent.objects[ents-2] == A, and
455 * ent.objects[ents-1] == B. Show diff between the
456 * base and B. Note that we pick one merge base at
457 * random if there are more than one.
c008c0ff 458 */
33055fa8
MH
459 result = builtin_diff_tree(&rev, argc, argv,
460 &ent.objects[0],
461 &ent.objects[ent.nr-1]);
c008c0ff 462 } else
41bbf9d5 463 result = builtin_diff_combined(&rev, argc, argv,
33055fa8 464 ent.objects, ent.nr);
da31b358 465 result = diff_result_code(&rev.diffopt, result);
aecbf914
JH
466 if (1 < rev.diffopt.skip_stat_unmatch)
467 refresh_index_quietly();
41bbf9d5 468 return result;
65056021 469}