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
17static 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
33static 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
48static 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 */
149static 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
175static 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
231static 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
250int 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
307int 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
336int 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 unsigned ce_option = ((option & DIFF_RACY_IS_MODIFIED)
342 ? CE_MATCH_RACY_IS_DIRTY : 0);
343
344 if (diff_unmerged_stage < 0)
345 diff_unmerged_stage = 2;
346 entries = active_nr;
347 for (i = 0; i < entries; i++) {
348 struct stat st;
349 unsigned int oldmode, newmode;
350 struct cache_entry *ce = active_cache[i];
351 int changed;
352
353 if (revs->diffopt.quiet && revs->diffopt.has_changes)
354 break;
355
356 if (!ce_path_match(ce, revs->prune_data))
357 continue;
358
359 if (ce_stage(ce)) {
360 struct combine_diff_path *dpath;
361 int num_compare_stages = 0;
362 size_t path_len;
363
364 path_len = ce_namelen(ce);
365
366 dpath = xmalloc(combine_diff_path_size(5, path_len));
367 dpath->path = (char *) &(dpath->parent[5]);
368
369 dpath->next = NULL;
370 dpath->len = path_len;
371 memcpy(dpath->path, ce->name, path_len);
372 dpath->path[path_len] = '\0';
373 hashclr(dpath->sha1);
374 memset(&(dpath->parent[0]), 0,
375 sizeof(struct combine_diff_parent)*5);
376
377 if (lstat(ce->name, &st) < 0) {
378 if (errno != ENOENT && errno != ENOTDIR) {
379 perror(ce->name);
380 continue;
381 }
382 if (silent_on_removed)
383 continue;
384 }
385 else
386 dpath->mode = ntohl(ce_mode_from_stat(ce, st.st_mode));
387
388 while (i < entries) {
389 struct cache_entry *nce = active_cache[i];
390 int stage;
391
392 if (strcmp(ce->name, nce->name))
393 break;
394
395 /* Stage #2 (ours) is the first parent,
396 * stage #3 (theirs) is the second.
397 */
398 stage = ce_stage(nce);
399 if (2 <= stage) {
400 int mode = ntohl(nce->ce_mode);
401 num_compare_stages++;
402 hashcpy(dpath->parent[stage-2].sha1, nce->sha1);
403 dpath->parent[stage-2].mode = ntohl(ce_mode_from_stat(nce, mode));
404 dpath->parent[stage-2].status =
405 DIFF_STATUS_MODIFIED;
406 }
407
408 /* diff against the proper unmerged stage */
409 if (stage == diff_unmerged_stage)
410 ce = nce;
411 i++;
412 }
413 /*
414 * Compensate for loop update
415 */
416 i--;
417
418 if (revs->combine_merges && num_compare_stages == 2) {
419 show_combined_diff(dpath, 2,
420 revs->dense_combined_merges,
421 revs);
422 free(dpath);
423 continue;
424 }
425 free(dpath);
426 dpath = NULL;
427
428 /*
429 * Show the diff for the 'ce' if we found the one
430 * from the desired stage.
431 */
432 diff_unmerge(&revs->diffopt, ce->name, 0, null_sha1);
433 if (ce_stage(ce) != diff_unmerged_stage)
434 continue;
435 }
436
437 if (lstat(ce->name, &st) < 0) {
438 if (errno != ENOENT && errno != ENOTDIR) {
439 perror(ce->name);
440 continue;
441 }
442 if (silent_on_removed)
443 continue;
444 diff_addremove(&revs->diffopt, '-', ntohl(ce->ce_mode),
445 ce->sha1, ce->name, NULL);
446 continue;
447 }
448 changed = ce_match_stat(ce, &st, ce_option);
449 if (!changed && !revs->diffopt.find_copies_harder)
450 continue;
451 oldmode = ntohl(ce->ce_mode);
452 newmode = ntohl(ce_mode_from_stat(ce, st.st_mode));
453 diff_change(&revs->diffopt, oldmode, newmode,
454 ce->sha1, (changed ? null_sha1 : ce->sha1),
455 ce->name, NULL);
456
457 }
458 diffcore_std(&revs->diffopt);
459 diff_flush(&revs->diffopt);
460 return 0;
461}
462
463/*
464 * diff-index
465 */
466
467/* A file entry went away or appeared */
468static void diff_index_show_file(struct rev_info *revs,
469 const char *prefix,
470 struct cache_entry *ce,
471 unsigned char *sha1, unsigned int mode)
472{
473 diff_addremove(&revs->diffopt, prefix[0], ntohl(mode),
474 sha1, ce->name, NULL);
475}
476
477static int get_stat_data(struct cache_entry *ce,
478 unsigned char **sha1p,
479 unsigned int *modep,
480 int cached, int match_missing)
481{
482 unsigned char *sha1 = ce->sha1;
483 unsigned int mode = ce->ce_mode;
484
485 if (!cached) {
486 static unsigned char no_sha1[20];
487 int changed;
488 struct stat st;
489 if (lstat(ce->name, &st) < 0) {
490 if (errno == ENOENT && match_missing) {
491 *sha1p = sha1;
492 *modep = mode;
493 return 0;
494 }
495 return -1;
496 }
497 changed = ce_match_stat(ce, &st, 0);
498 if (changed) {
499 mode = ce_mode_from_stat(ce, st.st_mode);
500 sha1 = no_sha1;
501 }
502 }
503
504 *sha1p = sha1;
505 *modep = mode;
506 return 0;
507}
508
509static void show_new_file(struct rev_info *revs,
510 struct cache_entry *new,
511 int cached, int match_missing)
512{
513 unsigned char *sha1;
514 unsigned int mode;
515
516 /* New file in the index: it might actually be different in
517 * the working copy.
518 */
519 if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0)
520 return;
521
522 diff_index_show_file(revs, "+", new, sha1, mode);
523}
524
525static int show_modified(struct rev_info *revs,
526 struct cache_entry *old,
527 struct cache_entry *new,
528 int report_missing,
529 int cached, int match_missing)
530{
531 unsigned int mode, oldmode;
532 unsigned char *sha1;
533
534 if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0) {
535 if (report_missing)
536 diff_index_show_file(revs, "-", old,
537 old->sha1, old->ce_mode);
538 return -1;
539 }
540
541 if (revs->combine_merges && !cached &&
542 (hashcmp(sha1, old->sha1) || hashcmp(old->sha1, new->sha1))) {
543 struct combine_diff_path *p;
544 int pathlen = ce_namelen(new);
545
546 p = xmalloc(combine_diff_path_size(2, pathlen));
547 p->path = (char *) &p->parent[2];
548 p->next = NULL;
549 p->len = pathlen;
550 memcpy(p->path, new->name, pathlen);
551 p->path[pathlen] = 0;
552 p->mode = ntohl(mode);
553 hashclr(p->sha1);
554 memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
555 p->parent[0].status = DIFF_STATUS_MODIFIED;
556 p->parent[0].mode = ntohl(new->ce_mode);
557 hashcpy(p->parent[0].sha1, new->sha1);
558 p->parent[1].status = DIFF_STATUS_MODIFIED;
559 p->parent[1].mode = ntohl(old->ce_mode);
560 hashcpy(p->parent[1].sha1, old->sha1);
561 show_combined_diff(p, 2, revs->dense_combined_merges, revs);
562 free(p);
563 return 0;
564 }
565
566 oldmode = old->ce_mode;
567 if (mode == oldmode && !hashcmp(sha1, old->sha1) &&
568 !revs->diffopt.find_copies_harder)
569 return 0;
570
571 mode = ntohl(mode);
572 oldmode = ntohl(oldmode);
573
574 diff_change(&revs->diffopt, oldmode, mode,
575 old->sha1, sha1, old->name, NULL);
576 return 0;
577}
578
579static int diff_cache(struct rev_info *revs,
580 struct cache_entry **ac, int entries,
581 const char **pathspec,
582 int cached, int match_missing)
583{
584 while (entries) {
585 struct cache_entry *ce = *ac;
586 int same = (entries > 1) && ce_same_name(ce, ac[1]);
587
588 if (revs->diffopt.quiet && revs->diffopt.has_changes)
589 break;
590
591 if (!ce_path_match(ce, pathspec))
592 goto skip_entry;
593
594 switch (ce_stage(ce)) {
595 case 0:
596 /* No stage 1 entry? That means it's a new file */
597 if (!same) {
598 show_new_file(revs, ce, cached, match_missing);
599 break;
600 }
601 /* Show difference between old and new */
602 show_modified(revs, ac[1], ce, 1,
603 cached, match_missing);
604 break;
605 case 1:
606 /* No stage 3 (merge) entry?
607 * That means it's been deleted.
608 */
609 if (!same) {
610 diff_index_show_file(revs, "-", ce,
611 ce->sha1, ce->ce_mode);
612 break;
613 }
614 /* We come here with ce pointing at stage 1
615 * (original tree) and ac[1] pointing at stage
616 * 3 (unmerged). show-modified with
617 * report-missing set to false does not say the
618 * file is deleted but reports true if work
619 * tree does not have it, in which case we
620 * fall through to report the unmerged state.
621 * Otherwise, we show the differences between
622 * the original tree and the work tree.
623 */
624 if (!cached &&
625 !show_modified(revs, ce, ac[1], 0,
626 cached, match_missing))
627 break;
628 diff_unmerge(&revs->diffopt, ce->name,
629 ntohl(ce->ce_mode), ce->sha1);
630 break;
631 case 3:
632 diff_unmerge(&revs->diffopt, ce->name,
633 0, null_sha1);
634 break;
635
636 default:
637 die("impossible cache entry stage");
638 }
639
640skip_entry:
641 /*
642 * Ignore all the different stages for this file,
643 * we've handled the relevant cases now.
644 */
645 do {
646 ac++;
647 entries--;
648 } while (entries && ce_same_name(ce, ac[0]));
649 }
650 return 0;
651}
652
653/*
654 * This turns all merge entries into "stage 3". That guarantees that
655 * when we read in the new tree (into "stage 1"), we won't lose sight
656 * of the fact that we had unmerged entries.
657 */
658static void mark_merge_entries(void)
659{
660 int i;
661 for (i = 0; i < active_nr; i++) {
662 struct cache_entry *ce = active_cache[i];
663 if (!ce_stage(ce))
664 continue;
665 ce->ce_flags |= htons(CE_STAGEMASK);
666 }
667}
668
669int run_diff_index(struct rev_info *revs, int cached)
670{
671 int ret;
672 struct object *ent;
673 struct tree *tree;
674 const char *tree_name;
675 int match_missing = 0;
676
677 /*
678 * Backward compatibility wart - "diff-index -m" does
679 * not mean "do not ignore merges", but totally different.
680 */
681 if (!revs->ignore_merges)
682 match_missing = 1;
683
684 mark_merge_entries();
685
686 ent = revs->pending.objects[0].item;
687 tree_name = revs->pending.objects[0].name;
688 tree = parse_tree_indirect(ent->sha1);
689 if (!tree)
690 return error("bad tree object %s", tree_name);
691 if (read_tree(tree, 1, revs->prune_data))
692 return error("unable to read tree object %s", tree_name);
693 ret = diff_cache(revs, active_cache, active_nr, revs->prune_data,
694 cached, match_missing);
695 diffcore_std(&revs->diffopt);
696 diff_flush(&revs->diffopt);
697 return ret;
698}
699
700int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
701{
702 struct tree *tree;
703 struct rev_info revs;
704 int i;
705 struct cache_entry **dst;
706 struct cache_entry *last = NULL;
707
708 /*
709 * This is used by git-blame to run diff-cache internally;
710 * it potentially needs to repeatedly run this, so we will
711 * start by removing the higher order entries the last round
712 * left behind.
713 */
714 dst = active_cache;
715 for (i = 0; i < active_nr; i++) {
716 struct cache_entry *ce = active_cache[i];
717 if (ce_stage(ce)) {
718 if (last && !strcmp(ce->name, last->name))
719 continue;
720 cache_tree_invalidate_path(active_cache_tree,
721 ce->name);
722 last = ce;
723 ce->ce_mode = 0;
724 ce->ce_flags &= ~htons(CE_STAGEMASK);
725 }
726 *dst++ = ce;
727 }
728 active_nr = dst - active_cache;
729
730 init_revisions(&revs, NULL);
731 revs.prune_data = opt->paths;
732 tree = parse_tree_indirect(tree_sha1);
733 if (!tree)
734 die("bad tree object %s", sha1_to_hex(tree_sha1));
735 if (read_tree(tree, 1, opt->paths))
736 return error("unable to read tree %s", sha1_to_hex(tree_sha1));
737 return diff_cache(&revs, active_cache, active_nr, revs.prune_data,
738 1, 0);
739}