ce_match_stat, run_diff_files: use symbolic constants for readability
[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(e->d_name, list);
28
29 closedir(dir);
30 return 0;
31 }
32
33 static int get_mode(const char *path, int *mode)
34 {
35 struct stat st;
36
37 if (!path || !strcmp(path, "/dev/null"))
38 *mode = 0;
39 else if (!strcmp(path, "-"))
40 *mode = ntohl(create_ce_mode(0666));
41 else if (stat(path, &st))
42 return error("Could not access '%s'", path);
43 else
44 *mode = st.st_mode;
45 return 0;
46 }
47
48 static int queue_diff(struct diff_options *o,
49 const char *name1, const char *name2)
50 {
51 int mode1 = 0, mode2 = 0;
52
53 if (get_mode(name1, &mode1) || get_mode(name2, &mode2))
54 return -1;
55
56 if (mode1 && mode2 && S_ISDIR(mode1) != S_ISDIR(mode2))
57 return error("file/directory conflict: %s, %s", name1, name2);
58
59 if (S_ISDIR(mode1) || S_ISDIR(mode2)) {
60 char buffer1[PATH_MAX], buffer2[PATH_MAX];
61 struct path_list p1 = {NULL, 0, 0, 1}, p2 = {NULL, 0, 0, 1};
62 int len1 = 0, len2 = 0, i1, i2, ret = 0;
63
64 if (name1 && read_directory(name1, &p1))
65 return -1;
66 if (name2 && read_directory(name2, &p2)) {
67 path_list_clear(&p1, 0);
68 return -1;
69 }
70
71 if (name1) {
72 len1 = strlen(name1);
73 if (len1 > 0 && name1[len1 - 1] == '/')
74 len1--;
75 memcpy(buffer1, name1, len1);
76 buffer1[len1++] = '/';
77 }
78
79 if (name2) {
80 len2 = strlen(name2);
81 if (len2 > 0 && name2[len2 - 1] == '/')
82 len2--;
83 memcpy(buffer2, name2, len2);
84 buffer2[len2++] = '/';
85 }
86
87 for (i1 = i2 = 0; !ret && (i1 < p1.nr || i2 < p2.nr); ) {
88 const char *n1, *n2;
89 int comp;
90
91 if (i1 == p1.nr)
92 comp = 1;
93 else if (i2 == p2.nr)
94 comp = -1;
95 else
96 comp = strcmp(p1.items[i1].path,
97 p2.items[i2].path);
98
99 if (comp > 0)
100 n1 = NULL;
101 else {
102 n1 = buffer1;
103 strncpy(buffer1 + len1, p1.items[i1++].path,
104 PATH_MAX - len1);
105 }
106
107 if (comp < 0)
108 n2 = NULL;
109 else {
110 n2 = buffer2;
111 strncpy(buffer2 + len2, p2.items[i2++].path,
112 PATH_MAX - len2);
113 }
114
115 ret = queue_diff(o, n1, n2);
116 }
117 path_list_clear(&p1, 0);
118 path_list_clear(&p2, 0);
119
120 return ret;
121 } else {
122 struct diff_filespec *d1, *d2;
123
124 if (o->reverse_diff) {
125 unsigned tmp;
126 const char *tmp_c;
127 tmp = mode1; mode1 = mode2; mode2 = tmp;
128 tmp_c = name1; name1 = name2; name2 = tmp_c;
129 }
130
131 if (!name1)
132 name1 = "/dev/null";
133 if (!name2)
134 name2 = "/dev/null";
135 d1 = alloc_filespec(name1);
136 d2 = alloc_filespec(name2);
137 fill_filespec(d1, null_sha1, mode1);
138 fill_filespec(d2, null_sha1, mode2);
139
140 diff_queue(&diff_queued_diff, d1, d2);
141 return 0;
142 }
143 }
144
145 /*
146 * Does the path name a blob in the working tree, or a directory
147 * in the working tree?
148 */
149 static int is_in_index(const char *path)
150 {
151 int len, pos;
152 struct cache_entry *ce;
153
154 len = strlen(path);
155 while (path[len-1] == '/')
156 len--;
157 if (!len)
158 return 1; /* "." */
159 pos = cache_name_pos(path, len);
160 if (0 <= pos)
161 return 1;
162 pos = -1 - pos;
163 while (pos < active_nr) {
164 ce = active_cache[pos++];
165 if (ce_namelen(ce) <= len ||
166 strncmp(ce->name, path, len) ||
167 (ce->name[len] > '/'))
168 break; /* path cannot be a prefix */
169 if (ce->name[len] == '/')
170 return 1;
171 }
172 return 0;
173 }
174
175 static int handle_diff_files_args(struct rev_info *revs,
176 int argc, const char **argv,
177 unsigned int *options)
178 {
179 *options = 0;
180
181 /* revs->max_count == -2 means --no-index */
182 while (1 < argc && argv[1][0] == '-') {
183 if (!strcmp(argv[1], "--base"))
184 revs->max_count = 1;
185 else if (!strcmp(argv[1], "--ours"))
186 revs->max_count = 2;
187 else if (!strcmp(argv[1], "--theirs"))
188 revs->max_count = 3;
189 else if (!strcmp(argv[1], "-n") ||
190 !strcmp(argv[1], "--no-index")) {
191 revs->max_count = -2;
192 revs->diffopt.exit_with_status = 1;
193 revs->diffopt.no_index = 1;
194 }
195 else if (!strcmp(argv[1], "-q"))
196 *options |= DIFF_SILENT_ON_REMOVED;
197 else
198 return error("invalid option: %s", argv[1]);
199 argv++; argc--;
200 }
201
202 if (revs->max_count == -1 && revs->diffopt.nr_paths == 2) {
203 /*
204 * If two files are specified, and at least one is untracked,
205 * default to no-index.
206 */
207 read_cache();
208 if (!is_in_index(revs->diffopt.paths[0]) ||
209 !is_in_index(revs->diffopt.paths[1])) {
210 revs->max_count = -2;
211 revs->diffopt.no_index = 1;
212 }
213 }
214
215 /*
216 * Make sure there are NO revision (i.e. pending object) parameter,
217 * rev.max_count is reasonable (0 <= n <= 3),
218 * there is no other revision filtering parameters.
219 */
220 if (revs->pending.nr || revs->max_count > 3 ||
221 revs->min_age != -1 || revs->max_age != -1)
222 return error("no revision allowed with diff-files");
223
224 if (revs->max_count == -1 &&
225 (revs->diffopt.output_format & DIFF_FORMAT_PATCH))
226 revs->combine_merges = revs->dense_combined_merges = 1;
227
228 return 0;
229 }
230
231 static int is_outside_repo(const char *path, int nongit, const char *prefix)
232 {
233 int i;
234 if (nongit || !strcmp(path, "-") || path[0] == '/')
235 return 1;
236 if (prefixcmp(path, "../"))
237 return 0;
238 if (!prefix)
239 return 1;
240 for (i = strlen(prefix); !prefixcmp(path, "../"); ) {
241 while (i > 0 && prefix[i - 1] != '/')
242 i--;
243 if (--i < 0)
244 return 1;
245 path += 3;
246 }
247 return 0;
248 }
249
250 int setup_diff_no_index(struct rev_info *revs,
251 int argc, const char ** argv, int nongit, const char *prefix)
252 {
253 int i;
254 for (i = 1; i < argc; i++)
255 if (argv[i][0] != '-' || argv[i][1] == '\0')
256 break;
257 else if (!strcmp(argv[i], "--")) {
258 i++;
259 break;
260 } else if (i < argc - 3 && !strcmp(argv[i], "--no-index")) {
261 i = argc - 3;
262 revs->diffopt.exit_with_status = 1;
263 break;
264 }
265 if (argc != i + 2 || (!is_outside_repo(argv[i + 1], nongit, prefix) &&
266 !is_outside_repo(argv[i], nongit, prefix)))
267 return -1;
268
269 diff_setup(&revs->diffopt);
270 for (i = 1; i < argc - 2; )
271 if (!strcmp(argv[i], "--no-index"))
272 i++;
273 else {
274 int j = diff_opt_parse(&revs->diffopt,
275 argv + i, argc - i);
276 if (!j)
277 die("invalid diff option/value: %s", argv[i]);
278 i += j;
279 }
280
281 if (prefix) {
282 int len = strlen(prefix);
283
284 revs->diffopt.paths = xcalloc(2, sizeof(char*));
285 for (i = 0; i < 2; i++) {
286 const char *p = argv[argc - 2 + i];
287 /*
288 * stdin should be spelled as '-'; if you have
289 * path that is '-', spell it as ./-.
290 */
291 p = (strcmp(p, "-")
292 ? xstrdup(prefix_filename(prefix, len, p))
293 : p);
294 revs->diffopt.paths[i] = p;
295 }
296 }
297 else
298 revs->diffopt.paths = argv + argc - 2;
299 revs->diffopt.nr_paths = 2;
300 revs->diffopt.no_index = 1;
301 revs->max_count = -2;
302 if (diff_setup_done(&revs->diffopt) < 0)
303 die("diff_setup_done failed");
304 return 0;
305 }
306
307 int run_diff_files_cmd(struct rev_info *revs, int argc, const char **argv)
308 {
309 unsigned int options;
310
311 if (handle_diff_files_args(revs, argc, argv, &options))
312 return -1;
313
314 if (revs->diffopt.no_index) {
315 if (revs->diffopt.nr_paths != 2)
316 return error("need two files/directories with --no-index");
317 if (queue_diff(&revs->diffopt, revs->diffopt.paths[0],
318 revs->diffopt.paths[1]))
319 return -1;
320 diffcore_std(&revs->diffopt);
321 diff_flush(&revs->diffopt);
322 /*
323 * The return code for --no-index imitates diff(1):
324 * 0 = no changes, 1 = changes, else error
325 */
326 return revs->diffopt.found_changes;
327 }
328
329 if (read_cache() < 0) {
330 perror("read_cache");
331 return -1;
332 }
333 return run_diff_files(revs, options);
334 }
335
336 int run_diff_files(struct rev_info *revs, unsigned int option)
337 {
338 int entries, i;
339 int diff_unmerged_stage = revs->max_count;
340 int silent_on_removed = option & DIFF_SILENT_ON_REMOVED;
341
342 if (diff_unmerged_stage < 0)
343 diff_unmerged_stage = 2;
344 entries = active_nr;
345 for (i = 0; i < entries; i++) {
346 struct stat st;
347 unsigned int oldmode, newmode;
348 struct cache_entry *ce = active_cache[i];
349 int changed;
350
351 if (revs->diffopt.quiet && revs->diffopt.has_changes)
352 break;
353
354 if (!ce_path_match(ce, revs->prune_data))
355 continue;
356
357 if (ce_stage(ce)) {
358 struct combine_diff_path *dpath;
359 int num_compare_stages = 0;
360 size_t path_len;
361
362 path_len = ce_namelen(ce);
363
364 dpath = xmalloc(combine_diff_path_size(5, path_len));
365 dpath->path = (char *) &(dpath->parent[5]);
366
367 dpath->next = NULL;
368 dpath->len = path_len;
369 memcpy(dpath->path, ce->name, path_len);
370 dpath->path[path_len] = '\0';
371 hashclr(dpath->sha1);
372 memset(&(dpath->parent[0]), 0,
373 sizeof(struct combine_diff_parent)*5);
374
375 if (lstat(ce->name, &st) < 0) {
376 if (errno != ENOENT && errno != ENOTDIR) {
377 perror(ce->name);
378 continue;
379 }
380 if (silent_on_removed)
381 continue;
382 }
383 else
384 dpath->mode = ntohl(ce_mode_from_stat(ce, st.st_mode));
385
386 while (i < entries) {
387 struct cache_entry *nce = active_cache[i];
388 int stage;
389
390 if (strcmp(ce->name, nce->name))
391 break;
392
393 /* Stage #2 (ours) is the first parent,
394 * stage #3 (theirs) is the second.
395 */
396 stage = ce_stage(nce);
397 if (2 <= stage) {
398 int mode = ntohl(nce->ce_mode);
399 num_compare_stages++;
400 hashcpy(dpath->parent[stage-2].sha1, nce->sha1);
401 dpath->parent[stage-2].mode = ntohl(ce_mode_from_stat(nce, mode));
402 dpath->parent[stage-2].status =
403 DIFF_STATUS_MODIFIED;
404 }
405
406 /* diff against the proper unmerged stage */
407 if (stage == diff_unmerged_stage)
408 ce = nce;
409 i++;
410 }
411 /*
412 * Compensate for loop update
413 */
414 i--;
415
416 if (revs->combine_merges && num_compare_stages == 2) {
417 show_combined_diff(dpath, 2,
418 revs->dense_combined_merges,
419 revs);
420 free(dpath);
421 continue;
422 }
423 free(dpath);
424 dpath = NULL;
425
426 /*
427 * Show the diff for the 'ce' if we found the one
428 * from the desired stage.
429 */
430 diff_unmerge(&revs->diffopt, ce->name, 0, null_sha1);
431 if (ce_stage(ce) != diff_unmerged_stage)
432 continue;
433 }
434
435 if (lstat(ce->name, &st) < 0) {
436 if (errno != ENOENT && errno != ENOTDIR) {
437 perror(ce->name);
438 continue;
439 }
440 if (silent_on_removed)
441 continue;
442 diff_addremove(&revs->diffopt, '-', ntohl(ce->ce_mode),
443 ce->sha1, ce->name, NULL);
444 continue;
445 }
446 changed = ce_match_stat(ce, &st, 0);
447 if (!changed && !revs->diffopt.find_copies_harder)
448 continue;
449 oldmode = ntohl(ce->ce_mode);
450 newmode = ntohl(ce_mode_from_stat(ce, st.st_mode));
451 diff_change(&revs->diffopt, oldmode, newmode,
452 ce->sha1, (changed ? null_sha1 : ce->sha1),
453 ce->name, NULL);
454
455 }
456 diffcore_std(&revs->diffopt);
457 diff_flush(&revs->diffopt);
458 return 0;
459 }
460
461 /*
462 * diff-index
463 */
464
465 /* A file entry went away or appeared */
466 static void diff_index_show_file(struct rev_info *revs,
467 const char *prefix,
468 struct cache_entry *ce,
469 unsigned char *sha1, unsigned int mode)
470 {
471 diff_addremove(&revs->diffopt, prefix[0], ntohl(mode),
472 sha1, ce->name, NULL);
473 }
474
475 static int get_stat_data(struct cache_entry *ce,
476 unsigned char **sha1p,
477 unsigned int *modep,
478 int cached, int match_missing)
479 {
480 unsigned char *sha1 = ce->sha1;
481 unsigned int mode = ce->ce_mode;
482
483 if (!cached) {
484 static unsigned char no_sha1[20];
485 int changed;
486 struct stat st;
487 if (lstat(ce->name, &st) < 0) {
488 if (errno == ENOENT && match_missing) {
489 *sha1p = sha1;
490 *modep = mode;
491 return 0;
492 }
493 return -1;
494 }
495 changed = ce_match_stat(ce, &st, 0);
496 if (changed) {
497 mode = ce_mode_from_stat(ce, st.st_mode);
498 sha1 = no_sha1;
499 }
500 }
501
502 *sha1p = sha1;
503 *modep = mode;
504 return 0;
505 }
506
507 static void show_new_file(struct rev_info *revs,
508 struct cache_entry *new,
509 int cached, int match_missing)
510 {
511 unsigned char *sha1;
512 unsigned int mode;
513
514 /* New file in the index: it might actually be different in
515 * the working copy.
516 */
517 if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0)
518 return;
519
520 diff_index_show_file(revs, "+", new, sha1, mode);
521 }
522
523 static int show_modified(struct rev_info *revs,
524 struct cache_entry *old,
525 struct cache_entry *new,
526 int report_missing,
527 int cached, int match_missing)
528 {
529 unsigned int mode, oldmode;
530 unsigned char *sha1;
531
532 if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0) {
533 if (report_missing)
534 diff_index_show_file(revs, "-", old,
535 old->sha1, old->ce_mode);
536 return -1;
537 }
538
539 if (revs->combine_merges && !cached &&
540 (hashcmp(sha1, old->sha1) || hashcmp(old->sha1, new->sha1))) {
541 struct combine_diff_path *p;
542 int pathlen = ce_namelen(new);
543
544 p = xmalloc(combine_diff_path_size(2, pathlen));
545 p->path = (char *) &p->parent[2];
546 p->next = NULL;
547 p->len = pathlen;
548 memcpy(p->path, new->name, pathlen);
549 p->path[pathlen] = 0;
550 p->mode = ntohl(mode);
551 hashclr(p->sha1);
552 memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
553 p->parent[0].status = DIFF_STATUS_MODIFIED;
554 p->parent[0].mode = ntohl(new->ce_mode);
555 hashcpy(p->parent[0].sha1, new->sha1);
556 p->parent[1].status = DIFF_STATUS_MODIFIED;
557 p->parent[1].mode = ntohl(old->ce_mode);
558 hashcpy(p->parent[1].sha1, old->sha1);
559 show_combined_diff(p, 2, revs->dense_combined_merges, revs);
560 free(p);
561 return 0;
562 }
563
564 oldmode = old->ce_mode;
565 if (mode == oldmode && !hashcmp(sha1, old->sha1) &&
566 !revs->diffopt.find_copies_harder)
567 return 0;
568
569 mode = ntohl(mode);
570 oldmode = ntohl(oldmode);
571
572 diff_change(&revs->diffopt, oldmode, mode,
573 old->sha1, sha1, old->name, NULL);
574 return 0;
575 }
576
577 static int diff_cache(struct rev_info *revs,
578 struct cache_entry **ac, int entries,
579 const char **pathspec,
580 int cached, int match_missing)
581 {
582 while (entries) {
583 struct cache_entry *ce = *ac;
584 int same = (entries > 1) && ce_same_name(ce, ac[1]);
585
586 if (revs->diffopt.quiet && revs->diffopt.has_changes)
587 break;
588
589 if (!ce_path_match(ce, pathspec))
590 goto skip_entry;
591
592 switch (ce_stage(ce)) {
593 case 0:
594 /* No stage 1 entry? That means it's a new file */
595 if (!same) {
596 show_new_file(revs, ce, cached, match_missing);
597 break;
598 }
599 /* Show difference between old and new */
600 show_modified(revs, ac[1], ce, 1,
601 cached, match_missing);
602 break;
603 case 1:
604 /* No stage 3 (merge) entry?
605 * That means it's been deleted.
606 */
607 if (!same) {
608 diff_index_show_file(revs, "-", ce,
609 ce->sha1, ce->ce_mode);
610 break;
611 }
612 /* We come here with ce pointing at stage 1
613 * (original tree) and ac[1] pointing at stage
614 * 3 (unmerged). show-modified with
615 * report-missing set to false does not say the
616 * file is deleted but reports true if work
617 * tree does not have it, in which case we
618 * fall through to report the unmerged state.
619 * Otherwise, we show the differences between
620 * the original tree and the work tree.
621 */
622 if (!cached &&
623 !show_modified(revs, ce, ac[1], 0,
624 cached, match_missing))
625 break;
626 diff_unmerge(&revs->diffopt, ce->name,
627 ntohl(ce->ce_mode), ce->sha1);
628 break;
629 case 3:
630 diff_unmerge(&revs->diffopt, ce->name,
631 0, null_sha1);
632 break;
633
634 default:
635 die("impossible cache entry stage");
636 }
637
638 skip_entry:
639 /*
640 * Ignore all the different stages for this file,
641 * we've handled the relevant cases now.
642 */
643 do {
644 ac++;
645 entries--;
646 } while (entries && ce_same_name(ce, ac[0]));
647 }
648 return 0;
649 }
650
651 /*
652 * This turns all merge entries into "stage 3". That guarantees that
653 * when we read in the new tree (into "stage 1"), we won't lose sight
654 * of the fact that we had unmerged entries.
655 */
656 static void mark_merge_entries(void)
657 {
658 int i;
659 for (i = 0; i < active_nr; i++) {
660 struct cache_entry *ce = active_cache[i];
661 if (!ce_stage(ce))
662 continue;
663 ce->ce_flags |= htons(CE_STAGEMASK);
664 }
665 }
666
667 int run_diff_index(struct rev_info *revs, int cached)
668 {
669 int ret;
670 struct object *ent;
671 struct tree *tree;
672 const char *tree_name;
673 int match_missing = 0;
674
675 /*
676 * Backward compatibility wart - "diff-index -m" does
677 * not mean "do not ignore merges", but totally different.
678 */
679 if (!revs->ignore_merges)
680 match_missing = 1;
681
682 mark_merge_entries();
683
684 ent = revs->pending.objects[0].item;
685 tree_name = revs->pending.objects[0].name;
686 tree = parse_tree_indirect(ent->sha1);
687 if (!tree)
688 return error("bad tree object %s", tree_name);
689 if (read_tree(tree, 1, revs->prune_data))
690 return error("unable to read tree object %s", tree_name);
691 ret = diff_cache(revs, active_cache, active_nr, revs->prune_data,
692 cached, match_missing);
693 diffcore_std(&revs->diffopt);
694 diff_flush(&revs->diffopt);
695 return ret;
696 }
697
698 int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
699 {
700 struct tree *tree;
701 struct rev_info revs;
702 int i;
703 struct cache_entry **dst;
704 struct cache_entry *last = NULL;
705
706 /*
707 * This is used by git-blame to run diff-cache internally;
708 * it potentially needs to repeatedly run this, so we will
709 * start by removing the higher order entries the last round
710 * left behind.
711 */
712 dst = active_cache;
713 for (i = 0; i < active_nr; i++) {
714 struct cache_entry *ce = active_cache[i];
715 if (ce_stage(ce)) {
716 if (last && !strcmp(ce->name, last->name))
717 continue;
718 cache_tree_invalidate_path(active_cache_tree,
719 ce->name);
720 last = ce;
721 ce->ce_mode = 0;
722 ce->ce_flags &= ~htons(CE_STAGEMASK);
723 }
724 *dst++ = ce;
725 }
726 active_nr = dst - active_cache;
727
728 init_revisions(&revs, NULL);
729 revs.prune_data = opt->paths;
730 tree = parse_tree_indirect(tree_sha1);
731 if (!tree)
732 die("bad tree object %s", sha1_to_hex(tree_sha1));
733 if (read_tree(tree, 1, opt->paths))
734 return error("unable to read tree %s", sha1_to_hex(tree_sha1));
735 return diff_cache(&revs, active_cache, active_nr, revs.prune_data,
736 1, 0);
737 }