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#include "unpack-trees.h"
13/*
15 * diff-files
16 */
17static int read_directory(const char *path, struct path_list *list)
19{
20 DIR *dir;
21 struct dirent *e;
22 if (!(dir = opendir(path)))
24 return error("Could not open directory %s", path);
25 while ((e = readdir(dir)))
27 if (strcmp(".", e->d_name) && strcmp("..", e->d_name))
28 path_list_insert(e->d_name, list);
29 closedir(dir);
31 return 0;
32}
33static int get_mode(const char *path, int *mode)
35{
36 struct stat st;
37 if (!path || !strcmp(path, "/dev/null"))
39 *mode = 0;
40 else if (!strcmp(path, "-"))
41 *mode = create_ce_mode(0666);
42 else if (stat(path, &st))
43 return error("Could not access '%s'", path);
44 else
45 *mode = st.st_mode;
46 return 0;
47}
48static int queue_diff(struct diff_options *o,
50 const char *name1, const char *name2)
51{
52 int mode1 = 0, mode2 = 0;
53 if (get_mode(name1, &mode1) || get_mode(name2, &mode2))
55 return -1;
56 if (mode1 && mode2 && S_ISDIR(mode1) != S_ISDIR(mode2))
58 return error("file/directory conflict: %s, %s", name1, name2);
59 if (S_ISDIR(mode1) || S_ISDIR(mode2)) {
61 char buffer1[PATH_MAX], buffer2[PATH_MAX];
62 struct path_list p1 = {NULL, 0, 0, 1}, p2 = {NULL, 0, 0, 1};
63 int len1 = 0, len2 = 0, i1, i2, ret = 0;
64 if (name1 && read_directory(name1, &p1))
66 return -1;
67 if (name2 && read_directory(name2, &p2)) {
68 path_list_clear(&p1, 0);
69 return -1;
70 }
71 if (name1) {
73 len1 = strlen(name1);
74 if (len1 > 0 && name1[len1 - 1] == '/')
75 len1--;
76 memcpy(buffer1, name1, len1);
77 buffer1[len1++] = '/';
78 }
79 if (name2) {
81 len2 = strlen(name2);
82 if (len2 > 0 && name2[len2 - 1] == '/')
83 len2--;
84 memcpy(buffer2, name2, len2);
85 buffer2[len2++] = '/';
86 }
87 for (i1 = i2 = 0; !ret && (i1 < p1.nr || i2 < p2.nr); ) {
89 const char *n1, *n2;
90 int comp;
91 if (i1 == p1.nr)
93 comp = 1;
94 else if (i2 == p2.nr)
95 comp = -1;
96 else
97 comp = strcmp(p1.items[i1].path,
98 p2.items[i2].path);
99 if (comp > 0)
101 n1 = NULL;
102 else {
103 n1 = buffer1;
104 strncpy(buffer1 + len1, p1.items[i1++].path,
105 PATH_MAX - len1);
106 }
107 if (comp < 0)
109 n2 = NULL;
110 else {
111 n2 = buffer2;
112 strncpy(buffer2 + len2, p2.items[i2++].path,
113 PATH_MAX - len2);
114 }
115 ret = queue_diff(o, n1, n2);
117 }
118 path_list_clear(&p1, 0);
119 path_list_clear(&p2, 0);
120 return ret;
122 } else {
123 struct diff_filespec *d1, *d2;
124 if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
126 unsigned tmp;
127 const char *tmp_c;
128 tmp = mode1; mode1 = mode2; mode2 = tmp;
129 tmp_c = name1; name1 = name2; name2 = tmp_c;
130 }
131 if (!name1)
133 name1 = "/dev/null";
134 if (!name2)
135 name2 = "/dev/null";
136 d1 = alloc_filespec(name1);
137 d2 = alloc_filespec(name2);
138 fill_filespec(d1, null_sha1, mode1);
139 fill_filespec(d2, null_sha1, mode2);
140 diff_queue(&diff_queued_diff, d1, d2);
142 return 0;
143 }
144}
145/*
147 * Does the path name a blob in the working tree, or a directory
148 * in the working tree?
149 */
150static int is_in_index(const char *path)
151{
152 int len, pos;
153 struct cache_entry *ce;
154 len = strlen(path);
156 while (path[len-1] == '/')
157 len--;
158 if (!len)
159 return 1; /* "." */
160 pos = cache_name_pos(path, len);
161 if (0 <= pos)
162 return 1;
163 pos = -1 - pos;
164 while (pos < active_nr) {
165 ce = active_cache[pos++];
166 if (ce_namelen(ce) <= len ||
167 strncmp(ce->name, path, len) ||
168 (ce->name[len] > '/'))
169 break; /* path cannot be a prefix */
170 if (ce->name[len] == '/')
171 return 1;
172 }
173 return 0;
174}
175static int handle_diff_files_args(struct rev_info *revs,
177 int argc, const char **argv,
178 unsigned int *options)
179{
180 *options = 0;
181 /* revs->max_count == -2 means --no-index */
183 while (1 < argc && argv[1][0] == '-') {
184 if (!strcmp(argv[1], "--base"))
185 revs->max_count = 1;
186 else if (!strcmp(argv[1], "--ours"))
187 revs->max_count = 2;
188 else if (!strcmp(argv[1], "--theirs"))
189 revs->max_count = 3;
190 else if (!strcmp(argv[1], "-n") ||
191 !strcmp(argv[1], "--no-index")) {
192 revs->max_count = -2;
193 DIFF_OPT_SET(&revs->diffopt, EXIT_WITH_STATUS);
194 DIFF_OPT_SET(&revs->diffopt, NO_INDEX);
195 }
196 else if (!strcmp(argv[1], "-q"))
197 *options |= DIFF_SILENT_ON_REMOVED;
198 else
199 return error("invalid option: %s", argv[1]);
200 argv++; argc--;
201 }
202 if (revs->max_count == -1 && revs->diffopt.nr_paths == 2) {
204 /*
205 * If two files are specified, and at least one is untracked,
206 * default to no-index.
207 */
208 read_cache();
209 if (!is_in_index(revs->diffopt.paths[0]) ||
210 !is_in_index(revs->diffopt.paths[1])) {
211 revs->max_count = -2;
212 DIFF_OPT_SET(&revs->diffopt, NO_INDEX);
213 }
214 }
215 /*
217 * Make sure there are NO revision (i.e. pending object) parameter,
218 * rev.max_count is reasonable (0 <= n <= 3),
219 * there is no other revision filtering parameters.
220 */
221 if (revs->pending.nr || revs->max_count > 3 ||
222 revs->min_age != -1 || revs->max_age != -1)
223 return error("no revision allowed with diff-files");
224 if (revs->max_count == -1 &&
226 (revs->diffopt.output_format & DIFF_FORMAT_PATCH))
227 revs->combine_merges = revs->dense_combined_merges = 1;
228 return 0;
230}
231static int is_outside_repo(const char *path, int nongit, const char *prefix)
233{
234 int i;
235 if (nongit || !strcmp(path, "-") || is_absolute_path(path))
236 return 1;
237 if (prefixcmp(path, "../"))
238 return 0;
239 if (!prefix)
240 return 1;
241 for (i = strlen(prefix); !prefixcmp(path, "../"); ) {
242 while (i > 0 && prefix[i - 1] != '/')
243 i--;
244 if (--i < 0)
245 return 1;
246 path += 3;
247 }
248 return 0;
249}
250int setup_diff_no_index(struct rev_info *revs,
252 int argc, const char ** argv, int nongit, const char *prefix)
253{
254 int i;
255 for (i = 1; i < argc; i++)
256 if (argv[i][0] != '-' || argv[i][1] == '\0')
257 break;
258 else if (!strcmp(argv[i], "--")) {
259 i++;
260 break;
261 } else if (i < argc - 3 && !strcmp(argv[i], "--no-index")) {
262 i = argc - 3;
263 DIFF_OPT_SET(&revs->diffopt, EXIT_WITH_STATUS);
264 break;
265 }
266 if (argc != i + 2 || (!is_outside_repo(argv[i + 1], nongit, prefix) &&
267 !is_outside_repo(argv[i], nongit, prefix)))
268 return -1;
269 diff_setup(&revs->diffopt);
271 for (i = 1; i < argc - 2; )
272 if (!strcmp(argv[i], "--no-index"))
273 i++;
274 else {
275 int j = diff_opt_parse(&revs->diffopt,
276 argv + i, argc - i);
277 if (!j)
278 die("invalid diff option/value: %s", argv[i]);
279 i += j;
280 }
281 if (prefix) {
283 int len = strlen(prefix);
284 revs->diffopt.paths = xcalloc(2, sizeof(char*));
286 for (i = 0; i < 2; i++) {
287 const char *p = argv[argc - 2 + i];
288 /*
289 * stdin should be spelled as '-'; if you have
290 * path that is '-', spell it as ./-.
291 */
292 p = (strcmp(p, "-")
293 ? xstrdup(prefix_filename(prefix, len, p))
294 : p);
295 revs->diffopt.paths[i] = p;
296 }
297 }
298 else
299 revs->diffopt.paths = argv + argc - 2;
300 revs->diffopt.nr_paths = 2;
301 DIFF_OPT_SET(&revs->diffopt, NO_INDEX);
302 revs->max_count = -2;
303 if (diff_setup_done(&revs->diffopt) < 0)
304 die("diff_setup_done failed");
305 return 0;
306}
307int run_diff_files_cmd(struct rev_info *revs, int argc, const char **argv)
309{
310 unsigned int options;
311 if (handle_diff_files_args(revs, argc, argv, &options))
313 return -1;
314 if (DIFF_OPT_TST(&revs->diffopt, NO_INDEX)) {
316 if (revs->diffopt.nr_paths != 2)
317 return error("need two files/directories with --no-index");
318 if (queue_diff(&revs->diffopt, revs->diffopt.paths[0],
319 revs->diffopt.paths[1]))
320 return -1;
321 diffcore_std(&revs->diffopt);
322 diff_flush(&revs->diffopt);
323 /*
324 * The return code for --no-index imitates diff(1):
325 * 0 = no changes, 1 = changes, else error
326 */
327 return revs->diffopt.found_changes;
328 }
329 if (read_cache() < 0) {
331 perror("read_cache");
332 return -1;
333 }
334 return run_diff_files(revs, options);
335}
336int run_diff_files(struct rev_info *revs, unsigned int option)
338{
339 int entries, i;
340 int diff_unmerged_stage = revs->max_count;
341 int silent_on_removed = option & DIFF_SILENT_ON_REMOVED;
342 unsigned ce_option = ((option & DIFF_RACY_IS_MODIFIED)
343 ? CE_MATCH_RACY_IS_DIRTY : 0);
344 if (diff_unmerged_stage < 0)
346 diff_unmerged_stage = 2;
347 entries = active_nr;
348 for (i = 0; i < entries; i++) {
349 struct stat st;
350 unsigned int oldmode, newmode;
351 struct cache_entry *ce = active_cache[i];
352 int changed;
353 if (DIFF_OPT_TST(&revs->diffopt, QUIET) &&
355 DIFF_OPT_TST(&revs->diffopt, HAS_CHANGES))
356 break;
357 if (!ce_path_match(ce, revs->prune_data))
359 continue;
360 if (ce_stage(ce)) {
362 struct combine_diff_path *dpath;
363 int num_compare_stages = 0;
364 size_t path_len;
365 path_len = ce_namelen(ce);
367 dpath = xmalloc(combine_diff_path_size(5, path_len));
369 dpath->path = (char *) &(dpath->parent[5]);
370 dpath->next = NULL;
372 dpath->len = path_len;
373 memcpy(dpath->path, ce->name, path_len);
374 dpath->path[path_len] = '\0';
375 hashclr(dpath->sha1);
376 memset(&(dpath->parent[0]), 0,
377 sizeof(struct combine_diff_parent)*5);
378 if (lstat(ce->name, &st) < 0) {
380 if (errno != ENOENT && errno != ENOTDIR) {
381 perror(ce->name);
382 continue;
383 }
384 if (silent_on_removed)
385 continue;
386 }
387 else
388 dpath->mode = ce_mode_from_stat(ce, st.st_mode);
389 while (i < entries) {
391 struct cache_entry *nce = active_cache[i];
392 int stage;
393 if (strcmp(ce->name, nce->name))
395 break;
396 /* Stage #2 (ours) is the first parent,
398 * stage #3 (theirs) is the second.
399 */
400 stage = ce_stage(nce);
401 if (2 <= stage) {
402 int mode = nce->ce_mode;
403 num_compare_stages++;
404 hashcpy(dpath->parent[stage-2].sha1, nce->sha1);
405 dpath->parent[stage-2].mode = ce_mode_from_stat(nce, mode);
406 dpath->parent[stage-2].status =
407 DIFF_STATUS_MODIFIED;
408 }
409 /* diff against the proper unmerged stage */
411 if (stage == diff_unmerged_stage)
412 ce = nce;
413 i++;
414 }
415 /*
416 * Compensate for loop update
417 */
418 i--;
419 if (revs->combine_merges && num_compare_stages == 2) {
421 show_combined_diff(dpath, 2,
422 revs->dense_combined_merges,
423 revs);
424 free(dpath);
425 continue;
426 }
427 free(dpath);
428 dpath = NULL;
429 /*
431 * Show the diff for the 'ce' if we found the one
432 * from the desired stage.
433 */
434 diff_unmerge(&revs->diffopt, ce->name, 0, null_sha1);
435 if (ce_stage(ce) != diff_unmerged_stage)
436 continue;
437 }
438 if (ce_uptodate(ce))
440 continue;
441 if (lstat(ce->name, &st) < 0) {
442 if (errno != ENOENT && errno != ENOTDIR) {
443 perror(ce->name);
444 continue;
445 }
446 if (silent_on_removed)
447 continue;
448 diff_addremove(&revs->diffopt, '-', ce->ce_mode,
449 ce->sha1, ce->name, NULL);
450 continue;
451 }
452 changed = ce_match_stat(ce, &st, ce_option);
453 if (!changed && !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
454 continue;
455 oldmode = ce->ce_mode;
456 newmode = ce_mode_from_stat(ce, st.st_mode);
457 diff_change(&revs->diffopt, oldmode, newmode,
458 ce->sha1, (changed ? null_sha1 : ce->sha1),
459 ce->name, NULL);
460 }
462 diffcore_std(&revs->diffopt);
463 diff_flush(&revs->diffopt);
464 return 0;
465}
466/*
468 * diff-index
469 */
470/* A file entry went away or appeared */
472static void diff_index_show_file(struct rev_info *revs,
473 const char *prefix,
474 struct cache_entry *ce,
475 const unsigned char *sha1, unsigned int mode)
476{
477 diff_addremove(&revs->diffopt, prefix[0], mode,
478 sha1, ce->name, NULL);
479}
480static int get_stat_data(struct cache_entry *ce,
482 const unsigned char **sha1p,
483 unsigned int *modep,
484 int cached, int match_missing)
485{
486 const unsigned char *sha1 = ce->sha1;
487 unsigned int mode = ce->ce_mode;
488 if (!cached) {
490 int changed;
491 struct stat st;
492 if (lstat(ce->name, &st) < 0) {
493 if (errno == ENOENT && match_missing) {
494 *sha1p = sha1;
495 *modep = mode;
496 return 0;
497 }
498 return -1;
499 }
500 changed = ce_match_stat(ce, &st, 0);
501 if (changed) {
502 mode = ce_mode_from_stat(ce, st.st_mode);
503 sha1 = null_sha1;
504 }
505 }
506 *sha1p = sha1;
508 *modep = mode;
509 return 0;
510}
511static void show_new_file(struct rev_info *revs,
513 struct cache_entry *new,
514 int cached, int match_missing)
515{
516 const unsigned char *sha1;
517 unsigned int mode;
518 /* New file in the index: it might actually be different in
520 * the working copy.
521 */
522 if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0)
523 return;
524 diff_index_show_file(revs, "+", new, sha1, mode);
526}
527static int show_modified(struct rev_info *revs,
529 struct cache_entry *old,
530 struct cache_entry *new,
531 int report_missing,
532 int cached, int match_missing)
533{
534 unsigned int mode, oldmode;
535 const unsigned char *sha1;
536 if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0) {
538 if (report_missing)
539 diff_index_show_file(revs, "-", old,
540 old->sha1, old->ce_mode);
541 return -1;
542 }
543 if (revs->combine_merges && !cached &&
545 (hashcmp(sha1, old->sha1) || hashcmp(old->sha1, new->sha1))) {
546 struct combine_diff_path *p;
547 int pathlen = ce_namelen(new);
548 p = xmalloc(combine_diff_path_size(2, pathlen));
550 p->path = (char *) &p->parent[2];
551 p->next = NULL;
552 p->len = pathlen;
553 memcpy(p->path, new->name, pathlen);
554 p->path[pathlen] = 0;
555 p->mode = mode;
556 hashclr(p->sha1);
557 memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
558 p->parent[0].status = DIFF_STATUS_MODIFIED;
559 p->parent[0].mode = new->ce_mode;
560 hashcpy(p->parent[0].sha1, new->sha1);
561 p->parent[1].status = DIFF_STATUS_MODIFIED;
562 p->parent[1].mode = old->ce_mode;
563 hashcpy(p->parent[1].sha1, old->sha1);
564 show_combined_diff(p, 2, revs->dense_combined_merges, revs);
565 free(p);
566 return 0;
567 }
568 oldmode = old->ce_mode;
570 if (mode == oldmode && !hashcmp(sha1, old->sha1) &&
571 !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
572 return 0;
573 diff_change(&revs->diffopt, oldmode, mode,
575 old->sha1, sha1, old->name, NULL);
576 return 0;
577}
578/*
580 * This turns all merge entries into "stage 3". That guarantees that
581 * when we read in the new tree (into "stage 1"), we won't lose sight
582 * of the fact that we had unmerged entries.
583 */
584static void mark_merge_entries(void)
585{
586 int i;
587 for (i = 0; i < active_nr; i++) {
588 struct cache_entry *ce = active_cache[i];
589 if (!ce_stage(ce))
590 continue;
591 ce->ce_flags |= CE_STAGEMASK;
592 }
593}
594/*
596 * This gets a mix of an existing index and a tree, one pathname entry
597 * at a time. The index entry may be a single stage-0 one, but it could
598 * also be multiple unmerged entries (in which case idx_pos/idx_nr will
599 * give you the position and number of entries in the index).
600 */
601static void do_oneway_diff(struct unpack_trees_options *o,
602 struct cache_entry *idx,
603 struct cache_entry *tree)
604{
605 struct rev_info *revs = o->unpack_data;
606 int match_missing, cached;
607 /*
609 * Backward compatibility wart - "diff-index -m" does
610 * not mean "do not ignore merges", but "match_missing".
611 *
612 * But with the revision flag parsing, that's found in
613 * "!revs->ignore_merges".
614 */
615 cached = o->index_only;
616 match_missing = !revs->ignore_merges;
617 if (cached && idx && ce_stage(idx)) {
619 if (tree)
620 diff_unmerge(&revs->diffopt, idx->name, idx->ce_mode, idx->sha1);
621 return;
622 }
623 /*
625 * Something added to the tree?
626 */
627 if (!tree) {
628 show_new_file(revs, idx, cached, match_missing);
629 return;
630 }
631 /*
633 * Something removed from the tree?
634 */
635 if (!idx) {
636 diff_index_show_file(revs, "-", tree, tree->sha1, tree->ce_mode);
637 return;
638 }
639 /* Show difference between old and new */
641 show_modified(revs, tree, idx, 1, cached, match_missing);
642}
643static inline void skip_same_name(struct cache_entry *ce, struct unpack_trees_options *o)
645{
646 int len = ce_namelen(ce);
647 const struct index_state *index = o->src_index;
648 while (o->pos < index->cache_nr) {
650 struct cache_entry *next = index->cache[o->pos];
651 if (len != ce_namelen(next))
652 break;
653 if (memcmp(ce->name, next->name, len))
654 break;
655 o->pos++;
656 }
657}
658/*
660 * The unpack_trees() interface is designed for merging, so
661 * the different source entries are designed primarily for
662 * the source trees, with the old index being really mainly
663 * used for being replaced by the result.
664 *
665 * For diffing, the index is more important, and we only have a
666 * single tree.
667 *
668 * We're supposed to return how many index entries we want to skip.
669 *
670 * This wrapper makes it all more readable, and takes care of all
671 * the fairly complex unpack_trees() semantic requirements, including
672 * the skipping, the path matching, the type conflict cases etc.
673 */
674static int oneway_diff(struct cache_entry **src, struct unpack_trees_options *o)
675{
676 struct cache_entry *idx = src[0];
677 struct cache_entry *tree = src[1];
678 struct rev_info *revs = o->unpack_data;
679 if (idx && ce_stage(idx))
681 skip_same_name(idx, o);
682 /*
684 * Unpack-trees generates a DF/conflict entry if
685 * there was a directory in the index and a tree
686 * in the tree. From a diff standpoint, that's a
687 * delete of the tree and a create of the file.
688 */
689 if (tree == o->df_conflict_entry)
690 tree = NULL;
691 if (ce_path_match(idx ? idx : tree, revs->prune_data))
693 do_oneway_diff(o, idx, tree);
694 return 0;
696}
697int run_diff_index(struct rev_info *revs, int cached)
699{
700 struct object *ent;
701 struct tree *tree;
702 const char *tree_name;
703 struct unpack_trees_options opts;
704 struct tree_desc t;
705 mark_merge_entries();
707 ent = revs->pending.objects[0].item;
709 tree_name = revs->pending.objects[0].name;
710 tree = parse_tree_indirect(ent->sha1);
711 if (!tree)
712 return error("bad tree object %s", tree_name);
713 memset(&opts, 0, sizeof(opts));
715 opts.head_idx = 1;
716 opts.index_only = cached;
717 opts.merge = 1;
718 opts.fn = oneway_diff;
719 opts.unpack_data = revs;
720 opts.src_index = &the_index;
721 opts.dst_index = NULL;
722 init_tree_desc(&t, tree->buffer, tree->size);
724 if (unpack_trees(1, &t, &opts))
725 exit(128);
726 diffcore_std(&revs->diffopt);
728 diff_flush(&revs->diffopt);
729 return 0;
730}
731int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
733{
734 struct tree *tree;
735 struct rev_info revs;
736 int i;
737 struct cache_entry **dst;
738 struct cache_entry *last = NULL;
739 struct unpack_trees_options opts;
740 struct tree_desc t;
741 /*
743 * This is used by git-blame to run diff-cache internally;
744 * it potentially needs to repeatedly run this, so we will
745 * start by removing the higher order entries the last round
746 * left behind.
747 */
748 dst = active_cache;
749 for (i = 0; i < active_nr; i++) {
750 struct cache_entry *ce = active_cache[i];
751 if (ce_stage(ce)) {
752 if (last && !strcmp(ce->name, last->name))
753 continue;
754 cache_tree_invalidate_path(active_cache_tree,
755 ce->name);
756 last = ce;
757 ce->ce_flags |= CE_REMOVE;
758 }
759 *dst++ = ce;
760 }
761 active_nr = dst - active_cache;
762 init_revisions(&revs, NULL);
764 revs.prune_data = opt->paths;
765 tree = parse_tree_indirect(tree_sha1);
766 if (!tree)
767 die("bad tree object %s", sha1_to_hex(tree_sha1));
768 memset(&opts, 0, sizeof(opts));
770 opts.head_idx = 1;
771 opts.index_only = 1;
772 opts.merge = 1;
773 opts.fn = oneway_diff;
774 opts.unpack_data = &revs;
775 opts.src_index = &the_index;
776 opts.dst_index = &the_index;
777 init_tree_desc(&t, tree->buffer, tree->size);
779 if (unpack_trees(1, &t, &opts))
780 exit(128);
781 return 0;
782}