1/*
2 * Builtin "git diff"
3 *
4 * Copyright (c) 2006 Junio C Hamano
5 */
6#include "cache.h"
7#include "color.h"
8#include "commit.h"
9#include "blob.h"
10#include "tag.h"
11#include "diff.h"
12#include "diffcore.h"
13#include "revision.h"
14#include "log-tree.h"
15#include "builtin.h"
16#include "submodule.h"
17#include "sha1-array.h"
18#define DIFF_NO_INDEX_EXPLICIT 1
20#define DIFF_NO_INDEX_IMPLICIT 2
21struct blobinfo {
23 unsigned char sha1[20];
24 const char *name;
25 unsigned mode;
26};
27static const char builtin_diff_usage[] =
29"git diff [<options>] [<commit> [<commit>]] [--] [<path>...]";
30static void stuff_change(struct diff_options *opt,
32 unsigned old_mode, unsigned new_mode,
33 const unsigned char *old_sha1,
34 const unsigned char *new_sha1,
35 int old_sha1_valid,
36 int new_sha1_valid,
37 const char *old_name,
38 const char *new_name)
39{
40 struct diff_filespec *one, *two;
41 if (!is_null_sha1(old_sha1) && !is_null_sha1(new_sha1) &&
43 !hashcmp(old_sha1, new_sha1) && (old_mode == new_mode))
44 return;
45 if (DIFF_OPT_TST(opt, REVERSE_DIFF)) {
47 unsigned tmp;
48 const unsigned char *tmp_u;
49 const char *tmp_c;
50 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
51 tmp_u = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_u;
52 tmp_c = old_name; old_name = new_name; new_name = tmp_c;
53 }
54 if (opt->prefix &&
56 (strncmp(old_name, opt->prefix, opt->prefix_length) ||
57 strncmp(new_name, opt->prefix, opt->prefix_length)))
58 return;
59 one = alloc_filespec(old_name);
61 two = alloc_filespec(new_name);
62 fill_filespec(one, old_sha1, old_sha1_valid, old_mode);
63 fill_filespec(two, new_sha1, new_sha1_valid, new_mode);
64 diff_queue(&diff_queued_diff, one, two);
66}
67static int builtin_diff_b_f(struct rev_info *revs,
69 int argc, const char **argv,
70 struct blobinfo *blob)
71{
72 /* Blob vs file in the working tree*/
73 struct stat st;
74 const char *path;
75 if (argc > 1)
77 usage(builtin_diff_usage);
78 GUARD_PATHSPEC(&revs->prune_data, PATHSPEC_FROMTOP | PATHSPEC_LITERAL);
80 path = revs->prune_data.items[0].match;
81 if (lstat(path, &st))
83 die_errno(_("failed to stat '%s'"), path);
84 if (!(S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)))
85 die(_("'%s': not a regular file or symlink"), path);
86 diff_set_mnemonic_prefix(&revs->diffopt, "o/", "w/");
88 if (blob[0].mode == S_IFINVALID)
90 blob[0].mode = canon_mode(st.st_mode);
91 stuff_change(&revs->diffopt,
93 blob[0].mode, canon_mode(st.st_mode),
94 blob[0].sha1, null_sha1,
95 1, 0,
96 path, path);
97 diffcore_std(&revs->diffopt);
98 diff_flush(&revs->diffopt);
99 return 0;
100}
101static int builtin_diff_blobs(struct rev_info *revs,
103 int argc, const char **argv,
104 struct blobinfo *blob)
105{
106 unsigned mode = canon_mode(S_IFREG | 0644);
107 if (argc > 1)
109 usage(builtin_diff_usage);
110 if (blob[0].mode == S_IFINVALID)
112 blob[0].mode = mode;
113 if (blob[1].mode == S_IFINVALID)
115 blob[1].mode = mode;
116 stuff_change(&revs->diffopt,
118 blob[0].mode, blob[1].mode,
119 blob[0].sha1, blob[1].sha1,
120 1, 1,
121 blob[0].name, blob[1].name);
122 diffcore_std(&revs->diffopt);
123 diff_flush(&revs->diffopt);
124 return 0;
125}
126static int builtin_diff_index(struct rev_info *revs,
128 int argc, const char **argv)
129{
130 int cached = 0;
131 while (1 < argc) {
132 const char *arg = argv[1];
133 if (!strcmp(arg, "--cached") || !strcmp(arg, "--staged"))
134 cached = 1;
135 else
136 usage(builtin_diff_usage);
137 argv++; argc--;
138 }
139 /*
140 * Make sure there is one revision (i.e. pending object),
141 * and there is no revision filtering parameters.
142 */
143 if (revs->pending.nr != 1 ||
144 revs->max_count != -1 || revs->min_age != -1 ||
145 revs->max_age != -1)
146 usage(builtin_diff_usage);
147 if (!cached) {
148 setup_work_tree();
149 if (read_cache_preload(&revs->diffopt.pathspec) < 0) {
150 perror("read_cache_preload");
151 return -1;
152 }
153 } else if (read_cache() < 0) {
154 perror("read_cache");
155 return -1;
156 }
157 return run_diff_index(revs, cached);
158}
159static int builtin_diff_tree(struct rev_info *revs,
161 int argc, const char **argv,
162 struct object_array_entry *ent0,
163 struct object_array_entry *ent1)
164{
165 const unsigned char *(sha1[2]);
166 int swap = 0;
167 if (argc > 1)
169 usage(builtin_diff_usage);
170 /*
172 * We saw two trees, ent0 and ent1. If ent1 is uninteresting,
173 * swap them.
174 */
175 if (ent1->item->flags & UNINTERESTING)
176 swap = 1;
177 sha1[swap] = ent0->item->sha1;
178 sha1[1 - swap] = ent1->item->sha1;
179 diff_tree_sha1(sha1[0], sha1[1], "", &revs->diffopt);
180 log_tree_diff_flush(revs);
181 return 0;
182}
183static int builtin_diff_combined(struct rev_info *revs,
185 int argc, const char **argv,
186 struct object_array_entry *ent,
187 int ents)
188{
189 struct sha1_array parents = SHA1_ARRAY_INIT;
190 int i;
191 if (argc > 1)
193 usage(builtin_diff_usage);
194 if (!revs->dense_combined_merges && !revs->combine_merges)
196 revs->dense_combined_merges = revs->combine_merges = 1;
197 for (i = 1; i < ents; i++)
198 sha1_array_append(&parents, ent[i].item->sha1);
199 diff_tree_combined(ent[0].item->sha1, &parents,
200 revs->dense_combined_merges, revs);
201 sha1_array_clear(&parents);
202 return 0;
203}
204static void refresh_index_quietly(void)
206{
207 struct lock_file *lock_file;
208 int fd;
209 lock_file = xcalloc(1, sizeof(struct lock_file));
211 fd = hold_locked_index(lock_file, 0);
212 if (fd < 0)
213 return;
214 discard_cache();
215 read_cache();
216 refresh_cache(REFRESH_QUIET|REFRESH_UNMERGED);
217 update_index_if_able(&the_index, lock_file);
218}
219static int builtin_diff_files(struct rev_info *revs, int argc, const char **argv)
221{
222 unsigned int options = 0;
223 while (1 < argc && argv[1][0] == '-') {
225 if (!strcmp(argv[1], "--base"))
226 revs->max_count = 1;
227 else if (!strcmp(argv[1], "--ours"))
228 revs->max_count = 2;
229 else if (!strcmp(argv[1], "--theirs"))
230 revs->max_count = 3;
231 else if (!strcmp(argv[1], "-q"))
232 options |= DIFF_SILENT_ON_REMOVED;
233 else if (!strcmp(argv[1], "-h"))
234 usage(builtin_diff_usage);
235 else
236 return error(_("invalid option: %s"), argv[1]);
237 argv++; argc--;
238 }
239 /*
241 * "diff --base" should not combine merges because it was not
242 * asked to. "diff -c" should not densify (if the user wants
243 * dense one, --cc can be explicitly asked for, or just rely
244 * on the default).
245 */
246 if (revs->max_count == -1 && !revs->combine_merges &&
247 (revs->diffopt.output_format & DIFF_FORMAT_PATCH))
248 revs->combine_merges = revs->dense_combined_merges = 1;
249 setup_work_tree();
251 if (read_cache_preload(&revs->diffopt.pathspec) < 0) {
252 perror("read_cache_preload");
253 return -1;
254 }
255 return run_diff_files(revs, options);
256}
257int cmd_diff(int argc, const char **argv, const char *prefix)
259{
260 int i;
261 struct rev_info rev;
262 struct object_array ent = OBJECT_ARRAY_INIT;
263 int blobs = 0, paths = 0;
264 struct blobinfo blob[2];
265 int nongit = 0, no_index = 0;
266 int result = 0;
267 /*
269 * We could get N tree-ish in the rev.pending_objects list.
270 * Also there could be M blobs there, and P pathspecs.
271 *
272 * N=0, M=0:
273 * cache vs files (diff-files)
274 * N=0, M=2:
275 * compare two random blobs. P must be zero.
276 * N=0, M=1, P=1:
277 * compare a blob with a working tree file.
278 *
279 * N=1, M=0:
280 * tree vs cache (diff-index --cached)
281 *
282 * N=2, M=0:
283 * tree vs tree (diff-tree)
284 *
285 * N=0, M=0, P=2:
286 * compare two filesystem entities (aka --no-index).
287 *
288 * Other cases are errors.
289 */
290 /* Were we asked to do --no-index explicitly? */
292 for (i = 1; i < argc; i++) {
293 if (!strcmp(argv[i], "--")) {
294 i++;
295 break;
296 }
297 if (!strcmp(argv[i], "--no-index"))
298 no_index = DIFF_NO_INDEX_EXPLICIT;
299 if (argv[i][0] != '-')
300 break;
301 }
302 if (!no_index)
304 prefix = setup_git_directory_gently(&nongit);
305 /*
307 * Treat git diff with at least one path outside of the
308 * repo the same as if the command would have been executed
309 * outside of a git repository. In this case it behaves
310 * the same way as "git diff --no-index <a> <b>", which acts
311 * as a colourful "diff" replacement.
312 */
313 if (nongit || ((argc == i + 2) &&
314 (!path_inside_repo(prefix, argv[i]) ||
315 !path_inside_repo(prefix, argv[i + 1]))))
316 no_index = DIFF_NO_INDEX_IMPLICIT;
317 if (!no_index)
319 gitmodules_config();
320 git_config(git_diff_ui_config, NULL);
321 init_revisions(&rev, prefix);
323 if (no_index && argc != i + 2) {
325 if (no_index == DIFF_NO_INDEX_IMPLICIT) {
326 /*
327 * There was no --no-index and there were not two
328 * paths. It is possible that the user intended
329 * to do an inside-repository operation.
330 */
331 fprintf(stderr, "Not a git repository\n");
332 fprintf(stderr,
333 "To compare two paths outside a working tree:\n");
334 }
335 /* Give the usage message for non-repository usage and exit. */
336 usagef("git diff %s <path> <path>",
337 no_index == DIFF_NO_INDEX_EXPLICIT ?
338 "--no-index" : "[--no-index]");
339 }
341 if (no_index)
342 /* If this is a no-index diff, just run it and exit there. */
343 diff_no_index(&rev, argc, argv, prefix);
344 /* Otherwise, we are doing the usual "git" diff */
346 rev.diffopt.skip_stat_unmatch = !!diff_auto_refresh_index;
347 /* Scale to real terminal size and respect statGraphWidth config */
349 rev.diffopt.stat_width = -1;
350 rev.diffopt.stat_graph_width = -1;
351 /* Default to let external and textconv be used */
353 DIFF_OPT_SET(&rev.diffopt, ALLOW_EXTERNAL);
354 DIFF_OPT_SET(&rev.diffopt, ALLOW_TEXTCONV);
355 if (nongit)
357 die(_("Not a git repository"));
358 argc = setup_revisions(argc, argv, &rev, NULL);
359 if (!rev.diffopt.output_format) {
360 rev.diffopt.output_format = DIFF_FORMAT_PATCH;
361 diff_setup_done(&rev.diffopt);
362 }
363 DIFF_OPT_SET(&rev.diffopt, RECURSIVE);
365 setup_diff_pager(&rev.diffopt);
367 /*
369 * Do we have --cached and not have a pending object, then
370 * default to HEAD by hand. Eek.
371 */
372 if (!rev.pending.nr) {
373 int i;
374 for (i = 1; i < argc; i++) {
375 const char *arg = argv[i];
376 if (!strcmp(arg, "--"))
377 break;
378 else if (!strcmp(arg, "--cached") ||
379 !strcmp(arg, "--staged")) {
380 add_head_to_pending(&rev);
381 if (!rev.pending.nr) {
382 struct tree *tree;
383 tree = lookup_tree(EMPTY_TREE_SHA1_BIN);
384 add_pending_object(&rev, &tree->object, "HEAD");
385 }
386 break;
387 }
388 }
389 }
390 for (i = 0; i < rev.pending.nr; i++) {
392 struct object_array_entry *entry = &rev.pending.objects[i];
393 struct object *obj = entry->item;
394 const char *name = entry->name;
395 int flags = (obj->flags & UNINTERESTING);
396 if (!obj->parsed)
397 obj = parse_object(obj->sha1);
398 obj = deref_tag(obj, NULL, 0);
399 if (!obj)
400 die(_("invalid object '%s' given."), name);
401 if (obj->type == OBJ_COMMIT)
402 obj = &((struct commit *)obj)->tree->object;
403 if (obj->type == OBJ_TREE) {
405 obj->flags |= flags;
406 add_object_array(obj, name, &ent);
407 } else if (obj->type == OBJ_BLOB) {
408 if (2 <= blobs)
409 die(_("more than two blobs given: '%s'"), name);
410 hashcpy(blob[blobs].sha1, obj->sha1);
411 blob[blobs].name = name;
412 blob[blobs].mode = entry->mode;
413 blobs++;
414 } else {
416 die(_("unhandled object '%s' given."), name);
417 }
418 }
419 if (rev.prune_data.nr)
420 paths += rev.prune_data.nr;
421 /*
423 * Now, do the arguments look reasonable?
424 */
425 if (!ent.nr) {
426 switch (blobs) {
427 case 0:
428 result = builtin_diff_files(&rev, argc, argv);
429 break;
430 case 1:
431 if (paths != 1)
432 usage(builtin_diff_usage);
433 result = builtin_diff_b_f(&rev, argc, argv, blob);
434 break;
435 case 2:
436 if (paths)
437 usage(builtin_diff_usage);
438 result = builtin_diff_blobs(&rev, argc, argv, blob);
439 break;
440 default:
441 usage(builtin_diff_usage);
442 }
443 }
444 else if (blobs)
445 usage(builtin_diff_usage);
446 else if (ent.nr == 1)
447 result = builtin_diff_index(&rev, argc, argv);
448 else if (ent.nr == 2)
449 result = builtin_diff_tree(&rev, argc, argv,
450 &ent.objects[0], &ent.objects[1]);
451 else if (ent.objects[0].item->flags & UNINTERESTING) {
452 /*
453 * diff A...B where there is at least one merge base
454 * between A and B. We have ent.objects[0] ==
455 * merge-base, ent.objects[ents-2] == A, and
456 * ent.objects[ents-1] == B. Show diff between the
457 * base and B. Note that we pick one merge base at
458 * random if there are more than one.
459 */
460 result = builtin_diff_tree(&rev, argc, argv,
461 &ent.objects[0],
462 &ent.objects[ent.nr-1]);
463 } else
464 result = builtin_diff_combined(&rev, argc, argv,
465 ent.objects, ent.nr);
466 result = diff_result_code(&rev.diffopt, result);
467 if (1 < rev.diffopt.skip_stat_unmatch)
468 refresh_index_quietly();
469 return result;
470}