Merge branch 'np/types'
[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 "path-list.h"
12
13 /*
14 * diff-files
15 */
16
17 static int read_directory(const char *path, struct path_list *list)
18 {
19 DIR *dir;
20 struct dirent *e;
21
22 if (!(dir = opendir(path)))
23 return error("Could not open directory %s", path);
24
25 while ((e = readdir(dir)))
26 if (strcmp(".", e->d_name) && strcmp("..", e->d_name))
27 path_list_insert(xstrdup(e->d_name), list);
28
29 closedir(dir);
30 return 0;
31 }
32
33 static int queue_diff(struct diff_options *o,
34 const char *name1, const char *name2)
35 {
36 struct stat st;
37 int mode1 = 0, mode2 = 0;
38
39 if (name1) {
40 if (stat(name1, &st))
41 return error("Could not access '%s'", name1);
42 mode1 = st.st_mode;
43 }
44 if (name2) {
45 if (stat(name2, &st))
46 return error("Could not access '%s'", name2);
47 mode2 = st.st_mode;
48 }
49
50 if (mode1 && mode2 && S_ISDIR(mode1) != S_ISDIR(mode2))
51 return error("file/directory conflict: %s, %s", name1, name2);
52
53 if (S_ISDIR(mode1) || S_ISDIR(mode2)) {
54 char buffer1[PATH_MAX], buffer2[PATH_MAX];
55 struct path_list p1 = {NULL, 0, 0, 1}, p2 = {NULL, 0, 0, 1};
56 int len1 = 0, len2 = 0, i1, i2, ret = 0;
57
58 if (name1 && read_directory(name1, &p1))
59 return -1;
60 if (name2 && read_directory(name2, &p2)) {
61 path_list_clear(&p1, 0);
62 return -1;
63 }
64
65 if (name1) {
66 len1 = strlen(name1);
67 if (len1 > 0 && name1[len1 - 1] == '/')
68 len1--;
69 memcpy(buffer1, name1, len1);
70 buffer1[len1++] = '/';
71 }
72
73 if (name2) {
74 len2 = strlen(name2);
75 if (len2 > 0 && name2[len2 - 1] == '/')
76 len2--;
77 memcpy(buffer2, name2, len2);
78 buffer2[len2++] = '/';
79 }
80
81 for (i1 = i2 = 0; !ret && (i1 < p1.nr || i2 < p2.nr); ) {
82 const char *n1, *n2;
83 int comp;
84
85 if (i1 == p1.nr)
86 comp = 1;
87 else if (i2 == p2.nr)
88 comp = -1;
89 else
90 comp = strcmp(p1.items[i1].path,
91 p2.items[i2].path);
92
93 if (comp > 0)
94 n1 = NULL;
95 else {
96 n1 = buffer1;
97 strncpy(buffer1 + len1, p1.items[i1++].path,
98 PATH_MAX - len1);
99 }
100
101 if (comp < 0)
102 n2 = NULL;
103 else {
104 n2 = buffer2;
105 strncpy(buffer2 + len2, p2.items[i2++].path,
106 PATH_MAX - len2);
107 }
108
109 ret = queue_diff(o, n1, n2);
110 }
111 path_list_clear(&p1, 0);
112 path_list_clear(&p2, 0);
113
114 return ret;
115 } else {
116 struct diff_filespec *d1, *d2;
117
118 if (o->reverse_diff) {
119 unsigned tmp;
120 const char *tmp_c;
121 tmp = mode1; mode1 = mode2; mode2 = tmp;
122 tmp_c = name1; name1 = name2; name2 = tmp_c;
123 }
124
125 if (!name1)
126 name1 = "/dev/null";
127 if (!name2)
128 name2 = "/dev/null";
129 d1 = alloc_filespec(name1);
130 d2 = alloc_filespec(name2);
131 fill_filespec(d1, null_sha1, mode1);
132 fill_filespec(d2, null_sha1, mode2);
133
134 diff_queue(&diff_queued_diff, d1, d2);
135 return 0;
136 }
137 }
138
139 static int is_in_index(const char *path)
140 {
141 int len = strlen(path);
142 int pos = cache_name_pos(path, len);
143 char c;
144
145 if (pos < 0)
146 return 0;
147 if (strncmp(active_cache[pos]->name, path, len))
148 return 0;
149 c = active_cache[pos]->name[len];
150 return c == '\0' || c == '/';
151 }
152
153 static int handle_diff_files_args(struct rev_info *revs,
154 int argc, const char **argv, int *silent)
155 {
156 *silent = 0;
157
158 /* revs->max_count == -2 means --no-index */
159 while (1 < argc && argv[1][0] == '-') {
160 if (!strcmp(argv[1], "--base"))
161 revs->max_count = 1;
162 else if (!strcmp(argv[1], "--ours"))
163 revs->max_count = 2;
164 else if (!strcmp(argv[1], "--theirs"))
165 revs->max_count = 3;
166 else if (!strcmp(argv[1], "-n") ||
167 !strcmp(argv[1], "--no-index"))
168 revs->max_count = -2;
169 else if (!strcmp(argv[1], "-q"))
170 *silent = 1;
171 else
172 return error("invalid option: %s", argv[1]);
173 argv++; argc--;
174 }
175
176 if (revs->max_count == -1 && revs->diffopt.nr_paths == 2) {
177 /*
178 * If two files are specified, and at least one is untracked,
179 * default to no-index.
180 */
181 read_cache();
182 if (!is_in_index(revs->diffopt.paths[0]) ||
183 !is_in_index(revs->diffopt.paths[1]))
184 revs->max_count = -2;
185 }
186
187 /*
188 * Make sure there are NO revision (i.e. pending object) parameter,
189 * rev.max_count is reasonable (0 <= n <= 3),
190 * there is no other revision filtering parameters.
191 */
192 if (revs->pending.nr || revs->max_count > 3 ||
193 revs->min_age != -1 || revs->max_age != -1)
194 return error("no revision allowed with diff-files");
195
196 if (revs->max_count == -1 &&
197 (revs->diffopt.output_format & DIFF_FORMAT_PATCH))
198 revs->combine_merges = revs->dense_combined_merges = 1;
199
200 return 0;
201 }
202
203 int run_diff_files_cmd(struct rev_info *revs, int argc, const char **argv)
204 {
205 int silent_on_removed;
206
207 if (handle_diff_files_args(revs, argc, argv, &silent_on_removed))
208 return -1;
209
210 if (revs->max_count == -2) {
211 if (revs->diffopt.nr_paths != 2)
212 return error("need two files/directories with --no-index");
213 if (queue_diff(&revs->diffopt, revs->diffopt.paths[0],
214 revs->diffopt.paths[1]))
215 return -1;
216 diffcore_std(&revs->diffopt);
217 diff_flush(&revs->diffopt);
218 /*
219 * The return code for --no-index imitates diff(1):
220 * 0 = no changes, 1 = changes, else error
221 */
222 return revs->diffopt.found_changes;
223 }
224
225 if (read_cache() < 0) {
226 perror("read_cache");
227 return -1;
228 }
229 return run_diff_files(revs, silent_on_removed);
230 }
231
232 int run_diff_files(struct rev_info *revs, int silent_on_removed)
233 {
234 int entries, i;
235 int diff_unmerged_stage = revs->max_count;
236
237 if (diff_unmerged_stage < 0)
238 diff_unmerged_stage = 2;
239 entries = active_nr;
240 for (i = 0; i < entries; i++) {
241 struct stat st;
242 unsigned int oldmode, newmode;
243 struct cache_entry *ce = active_cache[i];
244 int changed;
245
246 if (!ce_path_match(ce, revs->prune_data))
247 continue;
248
249 if (ce_stage(ce)) {
250 struct combine_diff_path *dpath;
251 int num_compare_stages = 0;
252 size_t path_len;
253
254 path_len = ce_namelen(ce);
255
256 dpath = xmalloc(combine_diff_path_size(5, path_len));
257 dpath->path = (char *) &(dpath->parent[5]);
258
259 dpath->next = NULL;
260 dpath->len = path_len;
261 memcpy(dpath->path, ce->name, path_len);
262 dpath->path[path_len] = '\0';
263 hashclr(dpath->sha1);
264 memset(&(dpath->parent[0]), 0,
265 sizeof(struct combine_diff_parent)*5);
266
267 if (lstat(ce->name, &st) < 0) {
268 if (errno != ENOENT && errno != ENOTDIR) {
269 perror(ce->name);
270 continue;
271 }
272 if (silent_on_removed)
273 continue;
274 }
275 else
276 dpath->mode = canon_mode(st.st_mode);
277
278 while (i < entries) {
279 struct cache_entry *nce = active_cache[i];
280 int stage;
281
282 if (strcmp(ce->name, nce->name))
283 break;
284
285 /* Stage #2 (ours) is the first parent,
286 * stage #3 (theirs) is the second.
287 */
288 stage = ce_stage(nce);
289 if (2 <= stage) {
290 int mode = ntohl(nce->ce_mode);
291 num_compare_stages++;
292 hashcpy(dpath->parent[stage-2].sha1, nce->sha1);
293 dpath->parent[stage-2].mode =
294 canon_mode(mode);
295 dpath->parent[stage-2].status =
296 DIFF_STATUS_MODIFIED;
297 }
298
299 /* diff against the proper unmerged stage */
300 if (stage == diff_unmerged_stage)
301 ce = nce;
302 i++;
303 }
304 /*
305 * Compensate for loop update
306 */
307 i--;
308
309 if (revs->combine_merges && num_compare_stages == 2) {
310 show_combined_diff(dpath, 2,
311 revs->dense_combined_merges,
312 revs);
313 free(dpath);
314 continue;
315 }
316 free(dpath);
317 dpath = NULL;
318
319 /*
320 * Show the diff for the 'ce' if we found the one
321 * from the desired stage.
322 */
323 diff_unmerge(&revs->diffopt, ce->name, 0, null_sha1);
324 if (ce_stage(ce) != diff_unmerged_stage)
325 continue;
326 }
327
328 if (lstat(ce->name, &st) < 0) {
329 if (errno != ENOENT && errno != ENOTDIR) {
330 perror(ce->name);
331 continue;
332 }
333 if (silent_on_removed)
334 continue;
335 diff_addremove(&revs->diffopt, '-', ntohl(ce->ce_mode),
336 ce->sha1, ce->name, NULL);
337 continue;
338 }
339 changed = ce_match_stat(ce, &st, 0);
340 if (!changed && !revs->diffopt.find_copies_harder)
341 continue;
342 oldmode = ntohl(ce->ce_mode);
343
344 newmode = canon_mode(st.st_mode);
345 if (!trust_executable_bit &&
346 S_ISREG(newmode) && S_ISREG(oldmode) &&
347 ((newmode ^ oldmode) == 0111))
348 newmode = oldmode;
349 diff_change(&revs->diffopt, oldmode, newmode,
350 ce->sha1, (changed ? null_sha1 : ce->sha1),
351 ce->name, NULL);
352
353 }
354 diffcore_std(&revs->diffopt);
355 diff_flush(&revs->diffopt);
356 return 0;
357 }
358
359 /*
360 * diff-index
361 */
362
363 /* A file entry went away or appeared */
364 static void diff_index_show_file(struct rev_info *revs,
365 const char *prefix,
366 struct cache_entry *ce,
367 unsigned char *sha1, unsigned int mode)
368 {
369 diff_addremove(&revs->diffopt, prefix[0], ntohl(mode),
370 sha1, ce->name, NULL);
371 }
372
373 static int get_stat_data(struct cache_entry *ce,
374 unsigned char **sha1p,
375 unsigned int *modep,
376 int cached, int match_missing)
377 {
378 unsigned char *sha1 = ce->sha1;
379 unsigned int mode = ce->ce_mode;
380
381 if (!cached) {
382 static unsigned char no_sha1[20];
383 int changed;
384 struct stat st;
385 if (lstat(ce->name, &st) < 0) {
386 if (errno == ENOENT && match_missing) {
387 *sha1p = sha1;
388 *modep = mode;
389 return 0;
390 }
391 return -1;
392 }
393 changed = ce_match_stat(ce, &st, 0);
394 if (changed) {
395 mode = ce_mode_from_stat(ce, st.st_mode);
396 sha1 = no_sha1;
397 }
398 }
399
400 *sha1p = sha1;
401 *modep = mode;
402 return 0;
403 }
404
405 static void show_new_file(struct rev_info *revs,
406 struct cache_entry *new,
407 int cached, int match_missing)
408 {
409 unsigned char *sha1;
410 unsigned int mode;
411
412 /* New file in the index: it might actually be different in
413 * the working copy.
414 */
415 if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0)
416 return;
417
418 diff_index_show_file(revs, "+", new, sha1, mode);
419 }
420
421 static int show_modified(struct rev_info *revs,
422 struct cache_entry *old,
423 struct cache_entry *new,
424 int report_missing,
425 int cached, int match_missing)
426 {
427 unsigned int mode, oldmode;
428 unsigned char *sha1;
429
430 if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0) {
431 if (report_missing)
432 diff_index_show_file(revs, "-", old,
433 old->sha1, old->ce_mode);
434 return -1;
435 }
436
437 if (revs->combine_merges && !cached &&
438 (hashcmp(sha1, old->sha1) || hashcmp(old->sha1, new->sha1))) {
439 struct combine_diff_path *p;
440 int pathlen = ce_namelen(new);
441
442 p = xmalloc(combine_diff_path_size(2, pathlen));
443 p->path = (char *) &p->parent[2];
444 p->next = NULL;
445 p->len = pathlen;
446 memcpy(p->path, new->name, pathlen);
447 p->path[pathlen] = 0;
448 p->mode = ntohl(mode);
449 hashclr(p->sha1);
450 memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
451 p->parent[0].status = DIFF_STATUS_MODIFIED;
452 p->parent[0].mode = ntohl(new->ce_mode);
453 hashcpy(p->parent[0].sha1, new->sha1);
454 p->parent[1].status = DIFF_STATUS_MODIFIED;
455 p->parent[1].mode = ntohl(old->ce_mode);
456 hashcpy(p->parent[1].sha1, old->sha1);
457 show_combined_diff(p, 2, revs->dense_combined_merges, revs);
458 free(p);
459 return 0;
460 }
461
462 oldmode = old->ce_mode;
463 if (mode == oldmode && !hashcmp(sha1, old->sha1) &&
464 !revs->diffopt.find_copies_harder)
465 return 0;
466
467 mode = ntohl(mode);
468 oldmode = ntohl(oldmode);
469
470 diff_change(&revs->diffopt, oldmode, mode,
471 old->sha1, sha1, old->name, NULL);
472 return 0;
473 }
474
475 static int diff_cache(struct rev_info *revs,
476 struct cache_entry **ac, int entries,
477 const char **pathspec,
478 int cached, int match_missing)
479 {
480 while (entries) {
481 struct cache_entry *ce = *ac;
482 int same = (entries > 1) && ce_same_name(ce, ac[1]);
483
484 if (!ce_path_match(ce, pathspec))
485 goto skip_entry;
486
487 switch (ce_stage(ce)) {
488 case 0:
489 /* No stage 1 entry? That means it's a new file */
490 if (!same) {
491 show_new_file(revs, ce, cached, match_missing);
492 break;
493 }
494 /* Show difference between old and new */
495 show_modified(revs, ac[1], ce, 1,
496 cached, match_missing);
497 break;
498 case 1:
499 /* No stage 3 (merge) entry?
500 * That means it's been deleted.
501 */
502 if (!same) {
503 diff_index_show_file(revs, "-", ce,
504 ce->sha1, ce->ce_mode);
505 break;
506 }
507 /* We come here with ce pointing at stage 1
508 * (original tree) and ac[1] pointing at stage
509 * 3 (unmerged). show-modified with
510 * report-missing set to false does not say the
511 * file is deleted but reports true if work
512 * tree does not have it, in which case we
513 * fall through to report the unmerged state.
514 * Otherwise, we show the differences between
515 * the original tree and the work tree.
516 */
517 if (!cached &&
518 !show_modified(revs, ce, ac[1], 0,
519 cached, match_missing))
520 break;
521 diff_unmerge(&revs->diffopt, ce->name,
522 ntohl(ce->ce_mode), ce->sha1);
523 break;
524 case 3:
525 diff_unmerge(&revs->diffopt, ce->name,
526 0, null_sha1);
527 break;
528
529 default:
530 die("impossible cache entry stage");
531 }
532
533 skip_entry:
534 /*
535 * Ignore all the different stages for this file,
536 * we've handled the relevant cases now.
537 */
538 do {
539 ac++;
540 entries--;
541 } while (entries && ce_same_name(ce, ac[0]));
542 }
543 return 0;
544 }
545
546 /*
547 * This turns all merge entries into "stage 3". That guarantees that
548 * when we read in the new tree (into "stage 1"), we won't lose sight
549 * of the fact that we had unmerged entries.
550 */
551 static void mark_merge_entries(void)
552 {
553 int i;
554 for (i = 0; i < active_nr; i++) {
555 struct cache_entry *ce = active_cache[i];
556 if (!ce_stage(ce))
557 continue;
558 ce->ce_flags |= htons(CE_STAGEMASK);
559 }
560 }
561
562 int run_diff_index(struct rev_info *revs, int cached)
563 {
564 int ret;
565 struct object *ent;
566 struct tree *tree;
567 const char *tree_name;
568 int match_missing = 0;
569
570 /*
571 * Backward compatibility wart - "diff-index -m" does
572 * not mean "do not ignore merges", but totally different.
573 */
574 if (!revs->ignore_merges)
575 match_missing = 1;
576
577 mark_merge_entries();
578
579 ent = revs->pending.objects[0].item;
580 tree_name = revs->pending.objects[0].name;
581 tree = parse_tree_indirect(ent->sha1);
582 if (!tree)
583 return error("bad tree object %s", tree_name);
584 if (read_tree(tree, 1, revs->prune_data))
585 return error("unable to read tree object %s", tree_name);
586 ret = diff_cache(revs, active_cache, active_nr, revs->prune_data,
587 cached, match_missing);
588 diffcore_std(&revs->diffopt);
589 diff_flush(&revs->diffopt);
590 return ret;
591 }
592
593 int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
594 {
595 struct tree *tree;
596 struct rev_info revs;
597 int i;
598 struct cache_entry **dst;
599 struct cache_entry *last = NULL;
600
601 /*
602 * This is used by git-blame to run diff-cache internally;
603 * it potentially needs to repeatedly run this, so we will
604 * start by removing the higher order entries the last round
605 * left behind.
606 */
607 dst = active_cache;
608 for (i = 0; i < active_nr; i++) {
609 struct cache_entry *ce = active_cache[i];
610 if (ce_stage(ce)) {
611 if (last && !strcmp(ce->name, last->name))
612 continue;
613 cache_tree_invalidate_path(active_cache_tree,
614 ce->name);
615 last = ce;
616 ce->ce_mode = 0;
617 ce->ce_flags &= ~htons(CE_STAGEMASK);
618 }
619 *dst++ = ce;
620 }
621 active_nr = dst - active_cache;
622
623 init_revisions(&revs, NULL);
624 revs.prune_data = opt->paths;
625 tree = parse_tree_indirect(tree_sha1);
626 if (!tree)
627 die("bad tree object %s", sha1_to_hex(tree_sha1));
628 if (read_tree(tree, 1, opt->paths))
629 return error("unable to read tree %s", sha1_to_hex(tree_sha1));
630 return diff_cache(&revs, active_cache, active_nr, revs.prune_data,
631 1, 0);
632 }