diff --quiet: disable optimization when --diff-filter=X is used
[git/git.git] / diff-lib.c
1 /*
2 * Copyright (C) 2005 Junio C Hamano
3 */
4 #include "cache.h"
5 #include "quote.h"
6 #include "commit.h"
7 #include "diff.h"
8 #include "diffcore.h"
9 #include "revision.h"
10 #include "cache-tree.h"
11 #include "unpack-trees.h"
12 #include "refs.h"
13
14 /*
15 * diff-files
16 */
17
18 /*
19 * Has the work tree entity been removed?
20 *
21 * Return 1 if it was removed from the work tree, 0 if an entity to be
22 * compared with the cache entry ce still exists (the latter includes
23 * the case where a directory that is not a submodule repository
24 * exists for ce that is a submodule -- it is a submodule that is not
25 * checked out). Return negative for an error.
26 */
27 static int check_removed(const struct cache_entry *ce, struct stat *st)
28 {
29 if (lstat(ce->name, st) < 0) {
30 if (errno != ENOENT && errno != ENOTDIR)
31 return -1;
32 return 1;
33 }
34 if (has_symlink_leading_path(ce->name, ce_namelen(ce)))
35 return 1;
36 if (S_ISDIR(st->st_mode)) {
37 unsigned char sub[20];
38
39 /*
40 * If ce is already a gitlink, we can have a plain
41 * directory (i.e. the submodule is not checked out),
42 * or a checked out submodule. Either case this is not
43 * a case where something was removed from the work tree,
44 * so we will return 0.
45 *
46 * Otherwise, if the directory is not a submodule
47 * repository, that means ce which was a blob turned into
48 * a directory --- the blob was removed!
49 */
50 if (!S_ISGITLINK(ce->ce_mode) &&
51 resolve_gitlink_ref(ce->name, "HEAD", sub))
52 return 1;
53 }
54 return 0;
55 }
56
57 int run_diff_files(struct rev_info *revs, unsigned int option)
58 {
59 int entries, i;
60 int diff_unmerged_stage = revs->max_count;
61 int silent_on_removed = option & DIFF_SILENT_ON_REMOVED;
62 unsigned ce_option = ((option & DIFF_RACY_IS_MODIFIED)
63 ? CE_MATCH_RACY_IS_DIRTY : 0);
64
65 diff_set_mnemonic_prefix(&revs->diffopt, "i/", "w/");
66
67 if (diff_unmerged_stage < 0)
68 diff_unmerged_stage = 2;
69 entries = active_nr;
70 for (i = 0; i < entries; i++) {
71 struct stat st;
72 unsigned int oldmode, newmode;
73 struct cache_entry *ce = active_cache[i];
74 int changed;
75
76 if (DIFF_OPT_TST(&revs->diffopt, QUICK) &&
77 !revs->diffopt.filter &&
78 DIFF_OPT_TST(&revs->diffopt, HAS_CHANGES))
79 break;
80
81 if (!ce_path_match(ce, revs->prune_data))
82 continue;
83
84 if (ce_stage(ce)) {
85 struct combine_diff_path *dpath;
86 int num_compare_stages = 0;
87 size_t path_len;
88
89 path_len = ce_namelen(ce);
90
91 dpath = xmalloc(combine_diff_path_size(5, path_len));
92 dpath->path = (char *) &(dpath->parent[5]);
93
94 dpath->next = NULL;
95 dpath->len = path_len;
96 memcpy(dpath->path, ce->name, path_len);
97 dpath->path[path_len] = '\0';
98 hashclr(dpath->sha1);
99 memset(&(dpath->parent[0]), 0,
100 sizeof(struct combine_diff_parent)*5);
101
102 changed = check_removed(ce, &st);
103 if (!changed)
104 dpath->mode = ce_mode_from_stat(ce, st.st_mode);
105 else {
106 if (changed < 0) {
107 perror(ce->name);
108 continue;
109 }
110 if (silent_on_removed)
111 continue;
112 }
113
114 while (i < entries) {
115 struct cache_entry *nce = active_cache[i];
116 int stage;
117
118 if (strcmp(ce->name, nce->name))
119 break;
120
121 /* Stage #2 (ours) is the first parent,
122 * stage #3 (theirs) is the second.
123 */
124 stage = ce_stage(nce);
125 if (2 <= stage) {
126 int mode = nce->ce_mode;
127 num_compare_stages++;
128 hashcpy(dpath->parent[stage-2].sha1, nce->sha1);
129 dpath->parent[stage-2].mode = ce_mode_from_stat(nce, mode);
130 dpath->parent[stage-2].status =
131 DIFF_STATUS_MODIFIED;
132 }
133
134 /* diff against the proper unmerged stage */
135 if (stage == diff_unmerged_stage)
136 ce = nce;
137 i++;
138 }
139 /*
140 * Compensate for loop update
141 */
142 i--;
143
144 if (revs->combine_merges && num_compare_stages == 2) {
145 show_combined_diff(dpath, 2,
146 revs->dense_combined_merges,
147 revs);
148 free(dpath);
149 continue;
150 }
151 free(dpath);
152 dpath = NULL;
153
154 /*
155 * Show the diff for the 'ce' if we found the one
156 * from the desired stage.
157 */
158 diff_unmerge(&revs->diffopt, ce->name, 0, null_sha1);
159 if (ce_stage(ce) != diff_unmerged_stage)
160 continue;
161 }
162
163 if (ce_uptodate(ce))
164 continue;
165
166 changed = check_removed(ce, &st);
167 if (changed) {
168 if (changed < 0) {
169 perror(ce->name);
170 continue;
171 }
172 if (silent_on_removed)
173 continue;
174 diff_addremove(&revs->diffopt, '-', ce->ce_mode,
175 ce->sha1, ce->name);
176 continue;
177 }
178 changed = ce_match_stat(ce, &st, ce_option);
179 if (!changed) {
180 ce_mark_uptodate(ce);
181 if (!DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
182 continue;
183 }
184 oldmode = ce->ce_mode;
185 newmode = ce_mode_from_stat(ce, st.st_mode);
186 diff_change(&revs->diffopt, oldmode, newmode,
187 ce->sha1, (changed ? null_sha1 : ce->sha1),
188 ce->name);
189
190 }
191 diffcore_std(&revs->diffopt);
192 diff_flush(&revs->diffopt);
193 return 0;
194 }
195
196 /*
197 * diff-index
198 */
199
200 /* A file entry went away or appeared */
201 static void diff_index_show_file(struct rev_info *revs,
202 const char *prefix,
203 struct cache_entry *ce,
204 const unsigned char *sha1, unsigned int mode)
205 {
206 diff_addremove(&revs->diffopt, prefix[0], mode,
207 sha1, ce->name);
208 }
209
210 static int get_stat_data(struct cache_entry *ce,
211 const unsigned char **sha1p,
212 unsigned int *modep,
213 int cached, int match_missing)
214 {
215 const unsigned char *sha1 = ce->sha1;
216 unsigned int mode = ce->ce_mode;
217
218 if (!cached && !ce_uptodate(ce)) {
219 int changed;
220 struct stat st;
221 changed = check_removed(ce, &st);
222 if (changed < 0)
223 return -1;
224 else if (changed) {
225 if (match_missing) {
226 *sha1p = sha1;
227 *modep = mode;
228 return 0;
229 }
230 return -1;
231 }
232 changed = ce_match_stat(ce, &st, 0);
233 if (changed) {
234 mode = ce_mode_from_stat(ce, st.st_mode);
235 sha1 = null_sha1;
236 }
237 }
238
239 *sha1p = sha1;
240 *modep = mode;
241 return 0;
242 }
243
244 static void show_new_file(struct rev_info *revs,
245 struct cache_entry *new,
246 int cached, int match_missing)
247 {
248 const unsigned char *sha1;
249 unsigned int mode;
250
251 /*
252 * New file in the index: it might actually be different in
253 * the working copy.
254 */
255 if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0)
256 return;
257
258 diff_index_show_file(revs, "+", new, sha1, mode);
259 }
260
261 static int show_modified(struct rev_info *revs,
262 struct cache_entry *old,
263 struct cache_entry *new,
264 int report_missing,
265 int cached, int match_missing)
266 {
267 unsigned int mode, oldmode;
268 const unsigned char *sha1;
269
270 if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0) {
271 if (report_missing)
272 diff_index_show_file(revs, "-", old,
273 old->sha1, old->ce_mode);
274 return -1;
275 }
276
277 if (revs->combine_merges && !cached &&
278 (hashcmp(sha1, old->sha1) || hashcmp(old->sha1, new->sha1))) {
279 struct combine_diff_path *p;
280 int pathlen = ce_namelen(new);
281
282 p = xmalloc(combine_diff_path_size(2, pathlen));
283 p->path = (char *) &p->parent[2];
284 p->next = NULL;
285 p->len = pathlen;
286 memcpy(p->path, new->name, pathlen);
287 p->path[pathlen] = 0;
288 p->mode = mode;
289 hashclr(p->sha1);
290 memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
291 p->parent[0].status = DIFF_STATUS_MODIFIED;
292 p->parent[0].mode = new->ce_mode;
293 hashcpy(p->parent[0].sha1, new->sha1);
294 p->parent[1].status = DIFF_STATUS_MODIFIED;
295 p->parent[1].mode = old->ce_mode;
296 hashcpy(p->parent[1].sha1, old->sha1);
297 show_combined_diff(p, 2, revs->dense_combined_merges, revs);
298 free(p);
299 return 0;
300 }
301
302 oldmode = old->ce_mode;
303 if (mode == oldmode && !hashcmp(sha1, old->sha1) &&
304 !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
305 return 0;
306
307 diff_change(&revs->diffopt, oldmode, mode,
308 old->sha1, sha1, old->name);
309 return 0;
310 }
311
312 /*
313 * This turns all merge entries into "stage 3". That guarantees that
314 * when we read in the new tree (into "stage 1"), we won't lose sight
315 * of the fact that we had unmerged entries.
316 */
317 static void mark_merge_entries(void)
318 {
319 int i;
320 for (i = 0; i < active_nr; i++) {
321 struct cache_entry *ce = active_cache[i];
322 if (!ce_stage(ce))
323 continue;
324 ce->ce_flags |= CE_STAGEMASK;
325 }
326 }
327
328 /*
329 * This gets a mix of an existing index and a tree, one pathname entry
330 * at a time. The index entry may be a single stage-0 one, but it could
331 * also be multiple unmerged entries (in which case idx_pos/idx_nr will
332 * give you the position and number of entries in the index).
333 */
334 static void do_oneway_diff(struct unpack_trees_options *o,
335 struct cache_entry *idx,
336 struct cache_entry *tree)
337 {
338 struct rev_info *revs = o->unpack_data;
339 int match_missing, cached;
340
341 /*
342 * Backward compatibility wart - "diff-index -m" does
343 * not mean "do not ignore merges", but "match_missing".
344 *
345 * But with the revision flag parsing, that's found in
346 * "!revs->ignore_merges".
347 */
348 cached = o->index_only;
349 match_missing = !revs->ignore_merges;
350
351 if (cached && idx && ce_stage(idx)) {
352 if (tree)
353 diff_unmerge(&revs->diffopt, idx->name, idx->ce_mode, idx->sha1);
354 return;
355 }
356
357 /*
358 * Something added to the tree?
359 */
360 if (!tree) {
361 show_new_file(revs, idx, cached, match_missing);
362 return;
363 }
364
365 /*
366 * Something removed from the tree?
367 */
368 if (!idx) {
369 diff_index_show_file(revs, "-", tree, tree->sha1, tree->ce_mode);
370 return;
371 }
372
373 /* Show difference between old and new */
374 show_modified(revs, tree, idx, 1, cached, match_missing);
375 }
376
377 static inline void skip_same_name(struct cache_entry *ce, struct unpack_trees_options *o)
378 {
379 int len = ce_namelen(ce);
380 const struct index_state *index = o->src_index;
381
382 while (o->pos < index->cache_nr) {
383 struct cache_entry *next = index->cache[o->pos];
384 if (len != ce_namelen(next))
385 break;
386 if (memcmp(ce->name, next->name, len))
387 break;
388 o->pos++;
389 }
390 }
391
392 /*
393 * The unpack_trees() interface is designed for merging, so
394 * the different source entries are designed primarily for
395 * the source trees, with the old index being really mainly
396 * used for being replaced by the result.
397 *
398 * For diffing, the index is more important, and we only have a
399 * single tree.
400 *
401 * We're supposed to return how many index entries we want to skip.
402 *
403 * This wrapper makes it all more readable, and takes care of all
404 * the fairly complex unpack_trees() semantic requirements, including
405 * the skipping, the path matching, the type conflict cases etc.
406 */
407 static int oneway_diff(struct cache_entry **src, struct unpack_trees_options *o)
408 {
409 struct cache_entry *idx = src[0];
410 struct cache_entry *tree = src[1];
411 struct rev_info *revs = o->unpack_data;
412
413 if (idx && ce_stage(idx))
414 skip_same_name(idx, o);
415
416 /*
417 * Unpack-trees generates a DF/conflict entry if
418 * there was a directory in the index and a tree
419 * in the tree. From a diff standpoint, that's a
420 * delete of the tree and a create of the file.
421 */
422 if (tree == o->df_conflict_entry)
423 tree = NULL;
424
425 if (ce_path_match(idx ? idx : tree, revs->prune_data))
426 do_oneway_diff(o, idx, tree);
427
428 return 0;
429 }
430
431 int run_diff_index(struct rev_info *revs, int cached)
432 {
433 struct object *ent;
434 struct tree *tree;
435 const char *tree_name;
436 struct unpack_trees_options opts;
437 struct tree_desc t;
438
439 mark_merge_entries();
440
441 ent = revs->pending.objects[0].item;
442 tree_name = revs->pending.objects[0].name;
443 tree = parse_tree_indirect(ent->sha1);
444 if (!tree)
445 return error("bad tree object %s", tree_name);
446
447 memset(&opts, 0, sizeof(opts));
448 opts.head_idx = 1;
449 opts.index_only = cached;
450 opts.diff_index_cached = (cached &&
451 !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER));
452 opts.merge = 1;
453 opts.fn = oneway_diff;
454 opts.unpack_data = revs;
455 opts.src_index = &the_index;
456 opts.dst_index = NULL;
457
458 init_tree_desc(&t, tree->buffer, tree->size);
459 if (unpack_trees(1, &t, &opts))
460 exit(128);
461
462 diff_set_mnemonic_prefix(&revs->diffopt, "c/", cached ? "i/" : "w/");
463 diffcore_std(&revs->diffopt);
464 diff_flush(&revs->diffopt);
465 return 0;
466 }
467
468 int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
469 {
470 struct tree *tree;
471 struct rev_info revs;
472 int i;
473 struct cache_entry **dst;
474 struct cache_entry *last = NULL;
475 struct unpack_trees_options opts;
476 struct tree_desc t;
477
478 /*
479 * This is used by git-blame to run diff-cache internally;
480 * it potentially needs to repeatedly run this, so we will
481 * start by removing the higher order entries the last round
482 * left behind.
483 */
484 dst = active_cache;
485 for (i = 0; i < active_nr; i++) {
486 struct cache_entry *ce = active_cache[i];
487 if (ce_stage(ce)) {
488 if (last && !strcmp(ce->name, last->name))
489 continue;
490 cache_tree_invalidate_path(active_cache_tree,
491 ce->name);
492 last = ce;
493 ce->ce_flags |= CE_REMOVE;
494 }
495 *dst++ = ce;
496 }
497 active_nr = dst - active_cache;
498
499 init_revisions(&revs, NULL);
500 revs.prune_data = opt->paths;
501 tree = parse_tree_indirect(tree_sha1);
502 if (!tree)
503 die("bad tree object %s", sha1_to_hex(tree_sha1));
504
505 memset(&opts, 0, sizeof(opts));
506 opts.head_idx = 1;
507 opts.index_only = 1;
508 opts.diff_index_cached = !DIFF_OPT_TST(opt, FIND_COPIES_HARDER);
509 opts.merge = 1;
510 opts.fn = oneway_diff;
511 opts.unpack_data = &revs;
512 opts.src_index = &the_index;
513 opts.dst_index = &the_index;
514
515 init_tree_desc(&t, tree->buffer, tree->size);
516 if (unpack_trees(1, &t, &opts))
517 exit(128);
518 return 0;
519 }
520
521 int index_differs_from(const char *def, int diff_flags)
522 {
523 struct rev_info rev;
524
525 init_revisions(&rev, NULL);
526 setup_revisions(0, NULL, &rev, def);
527 DIFF_OPT_SET(&rev.diffopt, QUICK);
528 DIFF_OPT_SET(&rev.diffopt, EXIT_WITH_STATUS);
529 rev.diffopt.flags |= diff_flags;
530 run_diff_index(&rev, 1);
531 if (rev.pending.alloc)
532 free(rev.pending.objects);
533 return (DIFF_OPT_TST(&rev.diffopt, HAS_CHANGES) != 0);
534 }