Git 1.7.9.7
[git/git.git] / builtin / diff.c
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
19 struct blobinfo {
20 unsigned char sha1[20];
21 const char *name;
22 unsigned mode;
23 };
24
25 static const char builtin_diff_usage[] =
26 "git diff [<options>] [<commit> [<commit>]] [--] [<path>...]";
27
28 static void stuff_change(struct diff_options *opt,
29 unsigned old_mode, unsigned new_mode,
30 const unsigned char *old_sha1,
31 const unsigned char *new_sha1,
32 const char *old_name,
33 const char *new_name)
34 {
35 struct diff_filespec *one, *two;
36
37 if (!is_null_sha1(old_sha1) && !is_null_sha1(new_sha1) &&
38 !hashcmp(old_sha1, new_sha1) && (old_mode == new_mode))
39 return;
40
41 if (DIFF_OPT_TST(opt, REVERSE_DIFF)) {
42 unsigned tmp;
43 const unsigned char *tmp_u;
44 const char *tmp_c;
45 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
46 tmp_u = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_u;
47 tmp_c = old_name; old_name = new_name; new_name = tmp_c;
48 }
49
50 if (opt->prefix &&
51 (strncmp(old_name, opt->prefix, opt->prefix_length) ||
52 strncmp(new_name, opt->prefix, opt->prefix_length)))
53 return;
54
55 one = alloc_filespec(old_name);
56 two = alloc_filespec(new_name);
57 fill_filespec(one, old_sha1, old_mode);
58 fill_filespec(two, new_sha1, new_mode);
59
60 diff_queue(&diff_queued_diff, one, two);
61 }
62
63 static int builtin_diff_b_f(struct rev_info *revs,
64 int argc, const char **argv,
65 struct blobinfo *blob,
66 const char *path)
67 {
68 /* Blob vs file in the working tree*/
69 struct stat st;
70
71 if (argc > 1)
72 usage(builtin_diff_usage);
73
74 if (lstat(path, &st))
75 die_errno(_("failed to stat '%s'"), path);
76 if (!(S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)))
77 die(_("'%s': not a regular file or symlink"), path);
78
79 diff_set_mnemonic_prefix(&revs->diffopt, "o/", "w/");
80
81 if (blob[0].mode == S_IFINVALID)
82 blob[0].mode = canon_mode(st.st_mode);
83
84 stuff_change(&revs->diffopt,
85 blob[0].mode, canon_mode(st.st_mode),
86 blob[0].sha1, null_sha1,
87 path, path);
88 diffcore_std(&revs->diffopt);
89 diff_flush(&revs->diffopt);
90 return 0;
91 }
92
93 static int builtin_diff_blobs(struct rev_info *revs,
94 int argc, const char **argv,
95 struct blobinfo *blob)
96 {
97 unsigned mode = canon_mode(S_IFREG | 0644);
98
99 if (argc > 1)
100 usage(builtin_diff_usage);
101
102 if (blob[0].mode == S_IFINVALID)
103 blob[0].mode = mode;
104
105 if (blob[1].mode == S_IFINVALID)
106 blob[1].mode = mode;
107
108 stuff_change(&revs->diffopt,
109 blob[0].mode, blob[1].mode,
110 blob[0].sha1, blob[1].sha1,
111 blob[0].name, blob[1].name);
112 diffcore_std(&revs->diffopt);
113 diff_flush(&revs->diffopt);
114 return 0;
115 }
116
117 static int builtin_diff_index(struct rev_info *revs,
118 int argc, const char **argv)
119 {
120 int cached = 0;
121 while (1 < argc) {
122 const char *arg = argv[1];
123 if (!strcmp(arg, "--cached") || !strcmp(arg, "--staged"))
124 cached = 1;
125 else
126 usage(builtin_diff_usage);
127 argv++; argc--;
128 }
129 if (!cached)
130 setup_work_tree();
131 /*
132 * Make sure there is one revision (i.e. pending object),
133 * and there is no revision filtering parameters.
134 */
135 if (revs->pending.nr != 1 ||
136 revs->max_count != -1 || revs->min_age != -1 ||
137 revs->max_age != -1)
138 usage(builtin_diff_usage);
139 if (read_cache_preload(revs->diffopt.pathspec.raw) < 0) {
140 perror("read_cache_preload");
141 return -1;
142 }
143 return run_diff_index(revs, cached);
144 }
145
146 static int builtin_diff_tree(struct rev_info *revs,
147 int argc, const char **argv,
148 struct object_array_entry *ent)
149 {
150 const unsigned char *(sha1[2]);
151 int swap = 0;
152
153 if (argc > 1)
154 usage(builtin_diff_usage);
155
156 /* We saw two trees, ent[0] and ent[1].
157 * if ent[1] is uninteresting, they are swapped
158 */
159 if (ent[1].item->flags & UNINTERESTING)
160 swap = 1;
161 sha1[swap] = ent[0].item->sha1;
162 sha1[1-swap] = ent[1].item->sha1;
163 diff_tree_sha1(sha1[0], sha1[1], "", &revs->diffopt);
164 log_tree_diff_flush(revs);
165 return 0;
166 }
167
168 static int builtin_diff_combined(struct rev_info *revs,
169 int argc, const char **argv,
170 struct object_array_entry *ent,
171 int ents)
172 {
173 struct sha1_array parents = SHA1_ARRAY_INIT;
174 int i;
175
176 if (argc > 1)
177 usage(builtin_diff_usage);
178
179 if (!revs->dense_combined_merges && !revs->combine_merges)
180 revs->dense_combined_merges = revs->combine_merges = 1;
181 for (i = 1; i < ents; i++)
182 sha1_array_append(&parents, ent[i].item->sha1);
183 diff_tree_combined(ent[0].item->sha1, &parents,
184 revs->dense_combined_merges, revs);
185 sha1_array_clear(&parents);
186 return 0;
187 }
188
189 static void refresh_index_quietly(void)
190 {
191 struct lock_file *lock_file;
192 int fd;
193
194 lock_file = xcalloc(1, sizeof(struct lock_file));
195 fd = hold_locked_index(lock_file, 0);
196 if (fd < 0)
197 return;
198 discard_cache();
199 read_cache();
200 refresh_cache(REFRESH_QUIET|REFRESH_UNMERGED);
201 update_index_if_able(&the_index, lock_file);
202 }
203
204 static int builtin_diff_files(struct rev_info *revs, int argc, const char **argv)
205 {
206 unsigned int options = 0;
207
208 while (1 < argc && argv[1][0] == '-') {
209 if (!strcmp(argv[1], "--base"))
210 revs->max_count = 1;
211 else if (!strcmp(argv[1], "--ours"))
212 revs->max_count = 2;
213 else if (!strcmp(argv[1], "--theirs"))
214 revs->max_count = 3;
215 else if (!strcmp(argv[1], "-q"))
216 options |= DIFF_SILENT_ON_REMOVED;
217 else if (!strcmp(argv[1], "-h"))
218 usage(builtin_diff_usage);
219 else
220 return error(_("invalid option: %s"), argv[1]);
221 argv++; argc--;
222 }
223
224 /*
225 * "diff --base" should not combine merges because it was not
226 * asked to. "diff -c" should not densify (if the user wants
227 * dense one, --cc can be explicitly asked for, or just rely
228 * on the default).
229 */
230 if (revs->max_count == -1 && !revs->combine_merges &&
231 (revs->diffopt.output_format & DIFF_FORMAT_PATCH))
232 revs->combine_merges = revs->dense_combined_merges = 1;
233
234 setup_work_tree();
235 if (read_cache_preload(revs->diffopt.pathspec.raw) < 0) {
236 perror("read_cache_preload");
237 return -1;
238 }
239 return run_diff_files(revs, options);
240 }
241
242 int cmd_diff(int argc, const char **argv, const char *prefix)
243 {
244 int i;
245 struct rev_info rev;
246 struct object_array_entry ent[100];
247 int ents = 0, blobs = 0, paths = 0;
248 const char *path = NULL;
249 struct blobinfo blob[2];
250 int nongit;
251 int result = 0;
252
253 /*
254 * We could get N tree-ish in the rev.pending_objects list.
255 * Also there could be M blobs there, and P pathspecs.
256 *
257 * N=0, M=0:
258 * cache vs files (diff-files)
259 * N=0, M=2:
260 * compare two random blobs. P must be zero.
261 * N=0, M=1, P=1:
262 * compare a blob with a working tree file.
263 *
264 * N=1, M=0:
265 * tree vs cache (diff-index --cached)
266 *
267 * N=2, M=0:
268 * tree vs tree (diff-tree)
269 *
270 * N=0, M=0, P=2:
271 * compare two filesystem entities (aka --no-index).
272 *
273 * Other cases are errors.
274 */
275
276 prefix = setup_git_directory_gently(&nongit);
277 gitmodules_config();
278 git_config(git_diff_ui_config, NULL);
279
280 init_revisions(&rev, prefix);
281
282 /* If this is a no-index diff, just run it and exit there. */
283 diff_no_index(&rev, argc, argv, nongit, prefix);
284
285 /* Otherwise, we are doing the usual "git" diff */
286 rev.diffopt.skip_stat_unmatch = !!diff_auto_refresh_index;
287
288 /* Default to let external and textconv be used */
289 DIFF_OPT_SET(&rev.diffopt, ALLOW_EXTERNAL);
290 DIFF_OPT_SET(&rev.diffopt, ALLOW_TEXTCONV);
291
292 if (nongit)
293 die(_("Not a git repository"));
294 argc = setup_revisions(argc, argv, &rev, NULL);
295 if (!rev.diffopt.output_format) {
296 rev.diffopt.output_format = DIFF_FORMAT_PATCH;
297 if (diff_setup_done(&rev.diffopt) < 0)
298 die(_("diff_setup_done failed"));
299 }
300
301 DIFF_OPT_SET(&rev.diffopt, RECURSIVE);
302
303 /*
304 * If the user asked for our exit code then don't start a
305 * pager or we would end up reporting its exit code instead.
306 */
307 if (!DIFF_OPT_TST(&rev.diffopt, EXIT_WITH_STATUS) &&
308 check_pager_config("diff") != 0)
309 setup_pager();
310
311 /*
312 * Do we have --cached and not have a pending object, then
313 * default to HEAD by hand. Eek.
314 */
315 if (!rev.pending.nr) {
316 int i;
317 for (i = 1; i < argc; i++) {
318 const char *arg = argv[i];
319 if (!strcmp(arg, "--"))
320 break;
321 else if (!strcmp(arg, "--cached") ||
322 !strcmp(arg, "--staged")) {
323 add_head_to_pending(&rev);
324 if (!rev.pending.nr) {
325 struct tree *tree;
326 tree = lookup_tree((const unsigned char*)EMPTY_TREE_SHA1_BIN);
327 add_pending_object(&rev, &tree->object, "HEAD");
328 }
329 break;
330 }
331 }
332 }
333
334 for (i = 0; i < rev.pending.nr; i++) {
335 struct object_array_entry *list = rev.pending.objects+i;
336 struct object *obj = list->item;
337 const char *name = list->name;
338 int flags = (obj->flags & UNINTERESTING);
339 if (!obj->parsed)
340 obj = parse_object(obj->sha1);
341 obj = deref_tag(obj, NULL, 0);
342 if (!obj)
343 die(_("invalid object '%s' given."), name);
344 if (obj->type == OBJ_COMMIT)
345 obj = &((struct commit *)obj)->tree->object;
346 if (obj->type == OBJ_TREE) {
347 if (ARRAY_SIZE(ent) <= ents)
348 die(_("more than %d trees given: '%s'"),
349 (int) ARRAY_SIZE(ent), name);
350 obj->flags |= flags;
351 ent[ents].item = obj;
352 ent[ents].name = name;
353 ents++;
354 continue;
355 }
356 if (obj->type == OBJ_BLOB) {
357 if (2 <= blobs)
358 die(_("more than two blobs given: '%s'"), name);
359 hashcpy(blob[blobs].sha1, obj->sha1);
360 blob[blobs].name = name;
361 blob[blobs].mode = list->mode;
362 blobs++;
363 continue;
364
365 }
366 die(_("unhandled object '%s' given."), name);
367 }
368 if (rev.prune_data.nr) {
369 if (!path)
370 path = rev.prune_data.items[0].match;
371 paths += rev.prune_data.nr;
372 }
373
374 /*
375 * Now, do the arguments look reasonable?
376 */
377 if (!ents) {
378 switch (blobs) {
379 case 0:
380 result = builtin_diff_files(&rev, argc, argv);
381 break;
382 case 1:
383 if (paths != 1)
384 usage(builtin_diff_usage);
385 result = builtin_diff_b_f(&rev, argc, argv, blob, path);
386 break;
387 case 2:
388 if (paths)
389 usage(builtin_diff_usage);
390 result = builtin_diff_blobs(&rev, argc, argv, blob);
391 break;
392 default:
393 usage(builtin_diff_usage);
394 }
395 }
396 else if (blobs)
397 usage(builtin_diff_usage);
398 else if (ents == 1)
399 result = builtin_diff_index(&rev, argc, argv);
400 else if (ents == 2)
401 result = builtin_diff_tree(&rev, argc, argv, ent);
402 else if (ent[0].item->flags & UNINTERESTING) {
403 /*
404 * diff A...B where there is at least one merge base
405 * between A and B. We have ent[0] == merge-base,
406 * ent[ents-2] == A, and ent[ents-1] == B. Show diff
407 * between the base and B. Note that we pick one
408 * merge base at random if there are more than one.
409 */
410 ent[1] = ent[ents-1];
411 result = builtin_diff_tree(&rev, argc, argv, ent);
412 } else
413 result = builtin_diff_combined(&rev, argc, argv,
414 ent, ents);
415 result = diff_result_code(&rev.diffopt, result);
416 if (1 < rev.diffopt.skip_stat_unmatch)
417 refresh_index_quietly();
418 return result;
419 }