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#include "submodule.h"
14#include "dir.h"
15/*
17 * diff-files
18 */
19/*
21 * Has the work tree entity been removed?
22 *
23 * Return 1 if it was removed from the work tree, 0 if an entity to be
24 * compared with the cache entry ce still exists (the latter includes
25 * the case where a directory that is not a submodule repository
26 * exists for ce that is a submodule -- it is a submodule that is not
27 * checked out). Return negative for an error.
28 */
29static int check_removed(const struct cache_entry *ce, struct stat *st)
30{
31 if (lstat(ce->name, st) < 0) {
32 if (errno != ENOENT && errno != ENOTDIR)
33 return -1;
34 return 1;
35 }
36 if (has_symlink_leading_path(ce->name, ce_namelen(ce)))
37 return 1;
38 if (S_ISDIR(st->st_mode)) {
39 unsigned char sub[20];
40 /*
42 * If ce is already a gitlink, we can have a plain
43 * directory (i.e. the submodule is not checked out),
44 * or a checked out submodule. Either case this is not
45 * a case where something was removed from the work tree,
46 * so we will return 0.
47 *
48 * Otherwise, if the directory is not a submodule
49 * repository, that means ce which was a blob turned into
50 * a directory --- the blob was removed!
51 */
52 if (!S_ISGITLINK(ce->ce_mode) &&
53 resolve_gitlink_ref(ce->name, "HEAD", sub))
54 return 1;
55 }
56 return 0;
57}
58/*
60 * Has a file changed or has a submodule new commits or a dirty work tree?
61 *
62 * Return 1 when changes are detected, 0 otherwise. If the DIRTY_SUBMODULES
63 * option is set, the caller does not only want to know if a submodule is
64 * modified at all but wants to know all the conditions that are met (new
65 * commits, untracked content and/or modified content).
66 */
67static int match_stat_with_submodule(struct diff_options *diffopt,
68 const struct cache_entry *ce,
69 struct stat *st, unsigned ce_option,
70 unsigned *dirty_submodule)
71{
72 int changed = ce_match_stat(ce, st, ce_option);
73 if (S_ISGITLINK(ce->ce_mode)) {
74 unsigned orig_flags = diffopt->flags;
75 if (!DIFF_OPT_TST(diffopt, OVERRIDE_SUBMODULE_CONFIG))
76 set_diffopt_flags_from_submodule_config(diffopt, ce->name);
77 if (DIFF_OPT_TST(diffopt, IGNORE_SUBMODULES))
78 changed = 0;
79 else if (!DIFF_OPT_TST(diffopt, IGNORE_DIRTY_SUBMODULES)
80 && (!changed || DIFF_OPT_TST(diffopt, DIRTY_SUBMODULES)))
81 *dirty_submodule = is_submodule_modified(ce->name, DIFF_OPT_TST(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES));
82 diffopt->flags = orig_flags;
83 }
84 return changed;
85}
86int run_diff_files(struct rev_info *revs, unsigned int option)
88{
89 int entries, i;
90 int diff_unmerged_stage = revs->max_count;
91 unsigned ce_option = ((option & DIFF_RACY_IS_MODIFIED)
92 ? CE_MATCH_RACY_IS_DIRTY : 0);
93 diff_set_mnemonic_prefix(&revs->diffopt, "i/", "w/");
95 if (diff_unmerged_stage < 0)
97 diff_unmerged_stage = 2;
98 entries = active_nr;
99 for (i = 0; i < entries; i++) {
100 unsigned int oldmode, newmode;
101 struct cache_entry *ce = active_cache[i];
102 int changed;
103 unsigned dirty_submodule = 0;
104 const unsigned char *old_sha1, *new_sha1;
105 if (diff_can_quit_early(&revs->diffopt))
107 break;
108 if (!ce_path_match(ce, &revs->prune_data, NULL))
110 continue;
111 if (ce_stage(ce)) {
113 struct combine_diff_path *dpath;
114 struct diff_filepair *pair;
115 unsigned int wt_mode = 0;
116 int num_compare_stages = 0;
117 size_t path_len;
118 struct stat st;
119 path_len = ce_namelen(ce);
121 dpath = xmalloc(combine_diff_path_size(5, path_len));
123 dpath->path = (char *) &(dpath->parent[5]);
124 dpath->next = NULL;
126 memcpy(dpath->path, ce->name, path_len);
127 dpath->path[path_len] = '\0';
128 oidclr(&dpath->oid);
129 memset(&(dpath->parent[0]), 0,
130 sizeof(struct combine_diff_parent)*5);
131 changed = check_removed(ce, &st);
133 if (!changed)
134 wt_mode = ce_mode_from_stat(ce, st.st_mode);
135 else {
136 if (changed < 0) {
137 perror(ce->name);
138 continue;
139 }
140 wt_mode = 0;
141 }
142 dpath->mode = wt_mode;
143 while (i < entries) {
145 struct cache_entry *nce = active_cache[i];
146 int stage;
147 if (strcmp(ce->name, nce->name))
149 break;
150 /* Stage #2 (ours) is the first parent,
152 * stage #3 (theirs) is the second.
153 */
154 stage = ce_stage(nce);
155 if (2 <= stage) {
156 int mode = nce->ce_mode;
157 num_compare_stages++;
158 hashcpy(dpath->parent[stage-2].oid.hash, nce->sha1);
159 dpath->parent[stage-2].mode = ce_mode_from_stat(nce, mode);
160 dpath->parent[stage-2].status =
161 DIFF_STATUS_MODIFIED;
162 }
163 /* diff against the proper unmerged stage */
165 if (stage == diff_unmerged_stage)
166 ce = nce;
167 i++;
168 }
169 /*
170 * Compensate for loop update
171 */
172 i--;
173 if (revs->combine_merges && num_compare_stages == 2) {
175 show_combined_diff(dpath, 2,
176 revs->dense_combined_merges,
177 revs);
178 free(dpath);
179 continue;
180 }
181 free(dpath);
182 dpath = NULL;
183 /*
185 * Show the diff for the 'ce' if we found the one
186 * from the desired stage.
187 */
188 pair = diff_unmerge(&revs->diffopt, ce->name);
189 if (wt_mode)
190 pair->two->mode = wt_mode;
191 if (ce_stage(ce) != diff_unmerged_stage)
192 continue;
193 }
194 if (ce_uptodate(ce) || ce_skip_worktree(ce))
196 continue;
197 /* If CE_VALID is set, don't look at workdir for file removal */
199 if (ce->ce_flags & CE_VALID) {
200 changed = 0;
201 newmode = ce->ce_mode;
202 } else {
203 struct stat st;
204 changed = check_removed(ce, &st);
206 if (changed) {
207 if (changed < 0) {
208 perror(ce->name);
209 continue;
210 }
211 diff_addremove(&revs->diffopt, '-', ce->ce_mode,
212 ce->sha1, !is_null_sha1(ce->sha1),
213 ce->name, 0);
214 continue;
215 } else if (ce->ce_flags & CE_INTENT_TO_ADD) {
216 diff_addremove(&revs->diffopt, '+', ce->ce_mode,
217 EMPTY_BLOB_SHA1_BIN, 0,
218 ce->name, 0);
219 continue;
220 }
221 changed = match_stat_with_submodule(&revs->diffopt, ce, &st,
223 ce_option, &dirty_submodule);
224 newmode = ce_mode_from_stat(ce, st.st_mode);
225 }
226 if (!changed && !dirty_submodule) {
228 ce_mark_uptodate(ce);
229 if (!DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
230 continue;
231 }
232 oldmode = ce->ce_mode;
233 old_sha1 = ce->sha1;
234 new_sha1 = changed ? null_sha1 : ce->sha1;
235 diff_change(&revs->diffopt, oldmode, newmode,
236 old_sha1, new_sha1,
237 !is_null_sha1(old_sha1),
238 !is_null_sha1(new_sha1),
239 ce->name, 0, dirty_submodule);
240 }
242 diffcore_std(&revs->diffopt);
243 diff_flush(&revs->diffopt);
244 return 0;
245}
246/*
248 * diff-index
249 */
250/* A file entry went away or appeared */
252static void diff_index_show_file(struct rev_info *revs,
253 const char *prefix,
254 const struct cache_entry *ce,
255 const unsigned char *sha1, int sha1_valid,
256 unsigned int mode,
257 unsigned dirty_submodule)
258{
259 diff_addremove(&revs->diffopt, prefix[0], mode,
260 sha1, sha1_valid, ce->name, dirty_submodule);
261}
262static int get_stat_data(const struct cache_entry *ce,
264 const unsigned char **sha1p,
265 unsigned int *modep,
266 int cached, int match_missing,
267 unsigned *dirty_submodule, struct diff_options *diffopt)
268{
269 const unsigned char *sha1 = ce->sha1;
270 unsigned int mode = ce->ce_mode;
271 if (!cached && !ce_uptodate(ce)) {
273 int changed;
274 struct stat st;
275 changed = check_removed(ce, &st);
276 if (changed < 0)
277 return -1;
278 else if (changed) {
279 if (match_missing) {
280 *sha1p = sha1;
281 *modep = mode;
282 return 0;
283 }
284 return -1;
285 }
286 changed = match_stat_with_submodule(diffopt, ce, &st,
287 0, dirty_submodule);
288 if (changed) {
289 mode = ce_mode_from_stat(ce, st.st_mode);
290 sha1 = null_sha1;
291 }
292 }
293 *sha1p = sha1;
295 *modep = mode;
296 return 0;
297}
298static void show_new_file(struct rev_info *revs,
300 const struct cache_entry *new,
301 int cached, int match_missing)
302{
303 const unsigned char *sha1;
304 unsigned int mode;
305 unsigned dirty_submodule = 0;
306 /*
308 * New file in the index: it might actually be different in
309 * the working tree.
310 */
311 if (get_stat_data(new, &sha1, &mode, cached, match_missing,
312 &dirty_submodule, &revs->diffopt) < 0)
313 return;
314 diff_index_show_file(revs, "+", new, sha1, !is_null_sha1(sha1), mode, dirty_submodule);
316}
317static int show_modified(struct rev_info *revs,
319 const struct cache_entry *old,
320 const struct cache_entry *new,
321 int report_missing,
322 int cached, int match_missing)
323{
324 unsigned int mode, oldmode;
325 const unsigned char *sha1;
326 unsigned dirty_submodule = 0;
327 if (get_stat_data(new, &sha1, &mode, cached, match_missing,
329 &dirty_submodule, &revs->diffopt) < 0) {
330 if (report_missing)
331 diff_index_show_file(revs, "-", old,
332 old->sha1, 1, old->ce_mode, 0);
333 return -1;
334 }
335 if (revs->combine_merges && !cached &&
337 (hashcmp(sha1, old->sha1) || hashcmp(old->sha1, new->sha1))) {
338 struct combine_diff_path *p;
339 int pathlen = ce_namelen(new);
340 p = xmalloc(combine_diff_path_size(2, pathlen));
342 p->path = (char *) &p->parent[2];
343 p->next = NULL;
344 memcpy(p->path, new->name, pathlen);
345 p->path[pathlen] = 0;
346 p->mode = mode;
347 oidclr(&p->oid);
348 memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
349 p->parent[0].status = DIFF_STATUS_MODIFIED;
350 p->parent[0].mode = new->ce_mode;
351 hashcpy(p->parent[0].oid.hash, new->sha1);
352 p->parent[1].status = DIFF_STATUS_MODIFIED;
353 p->parent[1].mode = old->ce_mode;
354 hashcpy(p->parent[1].oid.hash, old->sha1);
355 show_combined_diff(p, 2, revs->dense_combined_merges, revs);
356 free(p);
357 return 0;
358 }
359 oldmode = old->ce_mode;
361 if (mode == oldmode && !hashcmp(sha1, old->sha1) && !dirty_submodule &&
362 !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
363 return 0;
364 diff_change(&revs->diffopt, oldmode, mode,
366 old->sha1, sha1, 1, !is_null_sha1(sha1),
367 old->name, 0, dirty_submodule);
368 return 0;
369}
370/*
372 * This gets a mix of an existing index and a tree, one pathname entry
373 * at a time. The index entry may be a single stage-0 one, but it could
374 * also be multiple unmerged entries (in which case idx_pos/idx_nr will
375 * give you the position and number of entries in the index).
376 */
377static void do_oneway_diff(struct unpack_trees_options *o,
378 const struct cache_entry *idx,
379 const struct cache_entry *tree)
380{
381 struct rev_info *revs = o->unpack_data;
382 int match_missing, cached;
383 /* i-t-a entries do not actually exist in the index */
385 if (idx && (idx->ce_flags & CE_INTENT_TO_ADD)) {
386 idx = NULL;
387 if (!tree)
388 return; /* nothing to diff.. */
389 }
390 /* if the entry is not checked out, don't examine work tree */
392 cached = o->index_only ||
393 (idx && ((idx->ce_flags & CE_VALID) || ce_skip_worktree(idx)));
394 /*
395 * Backward compatibility wart - "diff-index -m" does
396 * not mean "do not ignore merges", but "match_missing".
397 *
398 * But with the revision flag parsing, that's found in
399 * "!revs->ignore_merges".
400 */
401 match_missing = !revs->ignore_merges;
402 if (cached && idx && ce_stage(idx)) {
404 struct diff_filepair *pair;
405 pair = diff_unmerge(&revs->diffopt, idx->name);
406 if (tree)
407 fill_filespec(pair->one, tree->sha1, 1, tree->ce_mode);
408 return;
409 }
410 /*
412 * Something added to the tree?
413 */
414 if (!tree) {
415 show_new_file(revs, idx, cached, match_missing);
416 return;
417 }
418 /*
420 * Something removed from the tree?
421 */
422 if (!idx) {
423 diff_index_show_file(revs, "-", tree, tree->sha1, 1, tree->ce_mode, 0);
424 return;
425 }
426 /* Show difference between old and new */
428 show_modified(revs, tree, idx, 1, cached, match_missing);
429}
430/*
432 * The unpack_trees() interface is designed for merging, so
433 * the different source entries are designed primarily for
434 * the source trees, with the old index being really mainly
435 * used for being replaced by the result.
436 *
437 * For diffing, the index is more important, and we only have a
438 * single tree.
439 *
440 * We're supposed to advance o->pos to skip what we have already processed.
441 *
442 * This wrapper makes it all more readable, and takes care of all
443 * the fairly complex unpack_trees() semantic requirements, including
444 * the skipping, the path matching, the type conflict cases etc.
445 */
446static int oneway_diff(const struct cache_entry * const *src,
447 struct unpack_trees_options *o)
448{
449 const struct cache_entry *idx = src[0];
450 const struct cache_entry *tree = src[1];
451 struct rev_info *revs = o->unpack_data;
452 /*
454 * Unpack-trees generates a DF/conflict entry if
455 * there was a directory in the index and a tree
456 * in the tree. From a diff standpoint, that's a
457 * delete of the tree and a create of the file.
458 */
459 if (tree == o->df_conflict_entry)
460 tree = NULL;
461 if (ce_path_match(idx ? idx : tree, &revs->prune_data, NULL)) {
463 do_oneway_diff(o, idx, tree);
464 if (diff_can_quit_early(&revs->diffopt)) {
465 o->exiting_early = 1;
466 return -1;
467 }
468 }
469 return 0;
471}
472static int diff_cache(struct rev_info *revs,
474 const unsigned char *tree_sha1,
475 const char *tree_name,
476 int cached)
477{
478 struct tree *tree;
479 struct tree_desc t;
480 struct unpack_trees_options opts;
481 tree = parse_tree_indirect(tree_sha1);
483 if (!tree)
484 return error("bad tree object %s",
485 tree_name ? tree_name : sha1_to_hex(tree_sha1));
486 memset(&opts, 0, sizeof(opts));
487 opts.head_idx = 1;
488 opts.index_only = cached;
489 opts.diff_index_cached = (cached &&
490 !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER));
491 opts.merge = 1;
492 opts.fn = oneway_diff;
493 opts.unpack_data = revs;
494 opts.src_index = &the_index;
495 opts.dst_index = NULL;
496 opts.pathspec = &revs->diffopt.pathspec;
497 opts.pathspec->recursive = 1;
498 init_tree_desc(&t, tree->buffer, tree->size);
500 return unpack_trees(1, &t, &opts);
501}
502int run_diff_index(struct rev_info *revs, int cached)
504{
505 struct object_array_entry *ent;
506 ent = revs->pending.objects;
508 if (diff_cache(revs, ent->item->sha1, ent->name, cached))
509 exit(128);
510 diff_set_mnemonic_prefix(&revs->diffopt, "c/", cached ? "i/" : "w/");
512 diffcore_fix_diff_index(&revs->diffopt);
513 diffcore_std(&revs->diffopt);
514 diff_flush(&revs->diffopt);
515 return 0;
516}
517int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
519{
520 struct rev_info revs;
521 init_revisions(&revs, NULL);
523 copy_pathspec(&revs.prune_data, &opt->pathspec);
524 revs.diffopt = *opt;
525 if (diff_cache(&revs, tree_sha1, NULL, 1))
527 exit(128);
528 return 0;
529}
530int index_differs_from(const char *def, int diff_flags)
532{
533 struct rev_info rev;
534 struct setup_revision_opt opt;
535 init_revisions(&rev, NULL);
537 memset(&opt, 0, sizeof(opt));
538 opt.def = def;
539 setup_revisions(0, NULL, &rev, &opt);
540 DIFF_OPT_SET(&rev.diffopt, QUICK);
541 DIFF_OPT_SET(&rev.diffopt, EXIT_WITH_STATUS);
542 rev.diffopt.flags |= diff_flags;
543 run_diff_index(&rev, 1);
544 if (rev.pending.alloc)
545 free(rev.pending.objects);
546 return (DIFF_OPT_TST(&rev.diffopt, HAS_CHANGES) != 0);
547}