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 oidcpy(&dpath->parent[stage - 2].oid,
159 &nce->oid);
160 dpath->parent[stage-2].mode = ce_mode_from_stat(nce, mode);
161 dpath->parent[stage-2].status =
162 DIFF_STATUS_MODIFIED;
163 }
164 /* diff against the proper unmerged stage */
166 if (stage == diff_unmerged_stage)
167 ce = nce;
168 i++;
169 }
170 /*
171 * Compensate for loop update
172 */
173 i--;
174 if (revs->combine_merges && num_compare_stages == 2) {
176 show_combined_diff(dpath, 2,
177 revs->dense_combined_merges,
178 revs);
179 free(dpath);
180 continue;
181 }
182 free(dpath);
183 dpath = NULL;
184 /*
186 * Show the diff for the 'ce' if we found the one
187 * from the desired stage.
188 */
189 pair = diff_unmerge(&revs->diffopt, ce->name);
190 if (wt_mode)
191 pair->two->mode = wt_mode;
192 if (ce_stage(ce) != diff_unmerged_stage)
193 continue;
194 }
195 if (ce_uptodate(ce) || ce_skip_worktree(ce))
197 continue;
198 /* If CE_VALID is set, don't look at workdir for file removal */
200 if (ce->ce_flags & CE_VALID) {
201 changed = 0;
202 newmode = ce->ce_mode;
203 } else {
204 struct stat st;
205 changed = check_removed(ce, &st);
207 if (changed) {
208 if (changed < 0) {
209 perror(ce->name);
210 continue;
211 }
212 diff_addremove(&revs->diffopt, '-', ce->ce_mode,
213 ce->oid.hash,
214 !is_null_oid(&ce->oid),
215 ce->name, 0);
216 continue;
217 }
218 changed = match_stat_with_submodule(&revs->diffopt, ce, &st,
220 ce_option, &dirty_submodule);
221 newmode = ce_mode_from_stat(ce, st.st_mode);
222 }
223 if (!changed && !dirty_submodule) {
225 ce_mark_uptodate(ce);
226 if (!DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
227 continue;
228 }
229 oldmode = ce->ce_mode;
230 old_sha1 = ce->oid.hash;
231 new_sha1 = changed ? null_sha1 : ce->oid.hash;
232 diff_change(&revs->diffopt, oldmode, newmode,
233 old_sha1, new_sha1,
234 !is_null_sha1(old_sha1),
235 !is_null_sha1(new_sha1),
236 ce->name, 0, dirty_submodule);
237 }
239 diffcore_std(&revs->diffopt);
240 diff_flush(&revs->diffopt);
241 return 0;
242}
243/*
245 * diff-index
246 */
247/* A file entry went away or appeared */
249static void diff_index_show_file(struct rev_info *revs,
250 const char *prefix,
251 const struct cache_entry *ce,
252 const unsigned char *sha1, int sha1_valid,
253 unsigned int mode,
254 unsigned dirty_submodule)
255{
256 diff_addremove(&revs->diffopt, prefix[0], mode,
257 sha1, sha1_valid, ce->name, dirty_submodule);
258}
259static int get_stat_data(const struct cache_entry *ce,
261 const unsigned char **sha1p,
262 unsigned int *modep,
263 int cached, int match_missing,
264 unsigned *dirty_submodule, struct diff_options *diffopt)
265{
266 const unsigned char *sha1 = ce->oid.hash;
267 unsigned int mode = ce->ce_mode;
268 if (!cached && !ce_uptodate(ce)) {
270 int changed;
271 struct stat st;
272 changed = check_removed(ce, &st);
273 if (changed < 0)
274 return -1;
275 else if (changed) {
276 if (match_missing) {
277 *sha1p = sha1;
278 *modep = mode;
279 return 0;
280 }
281 return -1;
282 }
283 changed = match_stat_with_submodule(diffopt, ce, &st,
284 0, dirty_submodule);
285 if (changed) {
286 mode = ce_mode_from_stat(ce, st.st_mode);
287 sha1 = null_sha1;
288 }
289 }
290 *sha1p = sha1;
292 *modep = mode;
293 return 0;
294}
295static void show_new_file(struct rev_info *revs,
297 const struct cache_entry *new,
298 int cached, int match_missing)
299{
300 const unsigned char *sha1;
301 unsigned int mode;
302 unsigned dirty_submodule = 0;
303 /*
305 * New file in the index: it might actually be different in
306 * the working tree.
307 */
308 if (get_stat_data(new, &sha1, &mode, cached, match_missing,
309 &dirty_submodule, &revs->diffopt) < 0)
310 return;
311 diff_index_show_file(revs, "+", new, sha1, !is_null_sha1(sha1), mode, dirty_submodule);
313}
314static int show_modified(struct rev_info *revs,
316 const struct cache_entry *old,
317 const struct cache_entry *new,
318 int report_missing,
319 int cached, int match_missing)
320{
321 unsigned int mode, oldmode;
322 const unsigned char *sha1;
323 unsigned dirty_submodule = 0;
324 if (get_stat_data(new, &sha1, &mode, cached, match_missing,
326 &dirty_submodule, &revs->diffopt) < 0) {
327 if (report_missing)
328 diff_index_show_file(revs, "-", old,
329 old->oid.hash, 1, old->ce_mode,
330 0);
331 return -1;
332 }
333 if (revs->combine_merges && !cached &&
335 (hashcmp(sha1, old->oid.hash) || oidcmp(&old->oid, &new->oid))) {
336 struct combine_diff_path *p;
337 int pathlen = ce_namelen(new);
338 p = xmalloc(combine_diff_path_size(2, pathlen));
340 p->path = (char *) &p->parent[2];
341 p->next = NULL;
342 memcpy(p->path, new->name, pathlen);
343 p->path[pathlen] = 0;
344 p->mode = mode;
345 oidclr(&p->oid);
346 memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
347 p->parent[0].status = DIFF_STATUS_MODIFIED;
348 p->parent[0].mode = new->ce_mode;
349 oidcpy(&p->parent[0].oid, &new->oid);
350 p->parent[1].status = DIFF_STATUS_MODIFIED;
351 p->parent[1].mode = old->ce_mode;
352 oidcpy(&p->parent[1].oid, &old->oid);
353 show_combined_diff(p, 2, revs->dense_combined_merges, revs);
354 free(p);
355 return 0;
356 }
357 oldmode = old->ce_mode;
359 if (mode == oldmode && !hashcmp(sha1, old->oid.hash) && !dirty_submodule &&
360 !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
361 return 0;
362 diff_change(&revs->diffopt, oldmode, mode,
364 old->oid.hash, sha1, 1, !is_null_sha1(sha1),
365 old->name, 0, dirty_submodule);
366 return 0;
367}
368/*
370 * This gets a mix of an existing index and a tree, one pathname entry
371 * at a time. The index entry may be a single stage-0 one, but it could
372 * also be multiple unmerged entries (in which case idx_pos/idx_nr will
373 * give you the position and number of entries in the index).
374 */
375static void do_oneway_diff(struct unpack_trees_options *o,
376 const struct cache_entry *idx,
377 const struct cache_entry *tree)
378{
379 struct rev_info *revs = o->unpack_data;
380 int match_missing, cached;
381 /* if the entry is not checked out, don't examine work tree */
383 cached = o->index_only ||
384 (idx && ((idx->ce_flags & CE_VALID) || ce_skip_worktree(idx)));
385 /*
386 * Backward compatibility wart - "diff-index -m" does
387 * not mean "do not ignore merges", but "match_missing".
388 *
389 * But with the revision flag parsing, that's found in
390 * "!revs->ignore_merges".
391 */
392 match_missing = !revs->ignore_merges;
393 if (cached && idx && ce_stage(idx)) {
395 struct diff_filepair *pair;
396 pair = diff_unmerge(&revs->diffopt, idx->name);
397 if (tree)
398 fill_filespec(pair->one, tree->oid.hash, 1,
399 tree->ce_mode);
400 return;
401 }
402 /*
404 * Something added to the tree?
405 */
406 if (!tree) {
407 show_new_file(revs, idx, cached, match_missing);
408 return;
409 }
410 /*
412 * Something removed from the tree?
413 */
414 if (!idx) {
415 diff_index_show_file(revs, "-", tree, tree->oid.hash, 1,
416 tree->ce_mode, 0);
417 return;
418 }
419 /* Show difference between old and new */
421 show_modified(revs, tree, idx, 1, cached, match_missing);
422}
423/*
425 * The unpack_trees() interface is designed for merging, so
426 * the different source entries are designed primarily for
427 * the source trees, with the old index being really mainly
428 * used for being replaced by the result.
429 *
430 * For diffing, the index is more important, and we only have a
431 * single tree.
432 *
433 * We're supposed to advance o->pos to skip what we have already processed.
434 *
435 * This wrapper makes it all more readable, and takes care of all
436 * the fairly complex unpack_trees() semantic requirements, including
437 * the skipping, the path matching, the type conflict cases etc.
438 */
439static int oneway_diff(const struct cache_entry * const *src,
440 struct unpack_trees_options *o)
441{
442 const struct cache_entry *idx = src[0];
443 const struct cache_entry *tree = src[1];
444 struct rev_info *revs = o->unpack_data;
445 /*
447 * Unpack-trees generates a DF/conflict entry if
448 * there was a directory in the index and a tree
449 * in the tree. From a diff standpoint, that's a
450 * delete of the tree and a create of the file.
451 */
452 if (tree == o->df_conflict_entry)
453 tree = NULL;
454 if (ce_path_match(idx ? idx : tree, &revs->prune_data, NULL)) {
456 do_oneway_diff(o, idx, tree);
457 if (diff_can_quit_early(&revs->diffopt)) {
458 o->exiting_early = 1;
459 return -1;
460 }
461 }
462 return 0;
464}
465static int diff_cache(struct rev_info *revs,
467 const unsigned char *tree_sha1,
468 const char *tree_name,
469 int cached)
470{
471 struct tree *tree;
472 struct tree_desc t;
473 struct unpack_trees_options opts;
474 tree = parse_tree_indirect(tree_sha1);
476 if (!tree)
477 return error("bad tree object %s",
478 tree_name ? tree_name : sha1_to_hex(tree_sha1));
479 memset(&opts, 0, sizeof(opts));
480 opts.head_idx = 1;
481 opts.index_only = cached;
482 opts.diff_index_cached = (cached &&
483 !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER));
484 opts.merge = 1;
485 opts.fn = oneway_diff;
486 opts.unpack_data = revs;
487 opts.src_index = &the_index;
488 opts.dst_index = NULL;
489 opts.pathspec = &revs->diffopt.pathspec;
490 opts.pathspec->recursive = 1;
491 init_tree_desc(&t, tree->buffer, tree->size);
493 return unpack_trees(1, &t, &opts);
494}
495int run_diff_index(struct rev_info *revs, int cached)
497{
498 struct object_array_entry *ent;
499 ent = revs->pending.objects;
501 if (diff_cache(revs, ent->item->oid.hash, ent->name, cached))
502 exit(128);
503 diff_set_mnemonic_prefix(&revs->diffopt, "c/", cached ? "i/" : "w/");
505 diffcore_fix_diff_index(&revs->diffopt);
506 diffcore_std(&revs->diffopt);
507 diff_flush(&revs->diffopt);
508 return 0;
509}
510int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
512{
513 struct rev_info revs;
514 init_revisions(&revs, NULL);
516 copy_pathspec(&revs.prune_data, &opt->pathspec);
517 revs.diffopt = *opt;
518 if (diff_cache(&revs, tree_sha1, NULL, 1))
520 exit(128);
521 return 0;
522}
523int index_differs_from(const char *def, int diff_flags)
525{
526 struct rev_info rev;
527 struct setup_revision_opt opt;
528 init_revisions(&rev, NULL);
530 memset(&opt, 0, sizeof(opt));
531 opt.def = def;
532 setup_revisions(0, NULL, &rev, &opt);
533 DIFF_OPT_SET(&rev.diffopt, QUICK);
534 DIFF_OPT_SET(&rev.diffopt, EXIT_WITH_STATUS);
535 rev.diffopt.flags |= diff_flags;
536 run_diff_index(&rev, 1);
537 if (rev.pending.alloc)
538 free(rev.pending.objects);
539 return (DIFF_OPT_TST(&rev.diffopt, HAS_CHANGES) != 0);
540}