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 if (option & DIFF_SILENT_ON_REMOVED)
95 handle_deprecated_show_diff_q(&revs->diffopt);
96 diff_set_mnemonic_prefix(&revs->diffopt, "i/", "w/");
98 if (diff_unmerged_stage < 0)
100 diff_unmerged_stage = 2;
101 entries = active_nr;
102 for (i = 0; i < entries; i++) {
103 struct stat st;
104 unsigned int oldmode, newmode;
105 struct cache_entry *ce = active_cache[i];
106 int changed;
107 unsigned dirty_submodule = 0;
108 if (diff_can_quit_early(&revs->diffopt))
110 break;
111 if (!ce_path_match(ce, &revs->prune_data, NULL))
113 continue;
114 if (ce_stage(ce)) {
116 struct combine_diff_path *dpath;
117 struct diff_filepair *pair;
118 unsigned int wt_mode = 0;
119 int num_compare_stages = 0;
120 size_t path_len;
121 path_len = ce_namelen(ce);
123 dpath = xmalloc(combine_diff_path_size(5, path_len));
125 dpath->path = (char *) &(dpath->parent[5]);
126 dpath->next = NULL;
128 memcpy(dpath->path, ce->name, path_len);
129 dpath->path[path_len] = '\0';
130 hashclr(dpath->sha1);
131 memset(&(dpath->parent[0]), 0,
132 sizeof(struct combine_diff_parent)*5);
133 changed = check_removed(ce, &st);
135 if (!changed)
136 wt_mode = ce_mode_from_stat(ce, st.st_mode);
137 else {
138 if (changed < 0) {
139 perror(ce->name);
140 continue;
141 }
142 wt_mode = 0;
143 }
144 dpath->mode = wt_mode;
145 while (i < entries) {
147 struct cache_entry *nce = active_cache[i];
148 int stage;
149 if (strcmp(ce->name, nce->name))
151 break;
152 /* Stage #2 (ours) is the first parent,
154 * stage #3 (theirs) is the second.
155 */
156 stage = ce_stage(nce);
157 if (2 <= stage) {
158 int mode = nce->ce_mode;
159 num_compare_stages++;
160 hashcpy(dpath->parent[stage-2].sha1, nce->sha1);
161 dpath->parent[stage-2].mode = ce_mode_from_stat(nce, mode);
162 dpath->parent[stage-2].status =
163 DIFF_STATUS_MODIFIED;
164 }
165 /* diff against the proper unmerged stage */
167 if (stage == diff_unmerged_stage)
168 ce = nce;
169 i++;
170 }
171 /*
172 * Compensate for loop update
173 */
174 i--;
175 if (revs->combine_merges && num_compare_stages == 2) {
177 show_combined_diff(dpath, 2,
178 revs->dense_combined_merges,
179 revs);
180 free(dpath);
181 continue;
182 }
183 free(dpath);
184 dpath = NULL;
185 /*
187 * Show the diff for the 'ce' if we found the one
188 * from the desired stage.
189 */
190 pair = diff_unmerge(&revs->diffopt, ce->name);
191 if (wt_mode)
192 pair->two->mode = wt_mode;
193 if (ce_stage(ce) != diff_unmerged_stage)
194 continue;
195 }
196 if (ce_uptodate(ce) || ce_skip_worktree(ce))
198 continue;
199 /* If CE_VALID is set, don't look at workdir for file removal */
201 changed = (ce->ce_flags & CE_VALID) ? 0 : check_removed(ce, &st);
202 if (changed) {
203 if (changed < 0) {
204 perror(ce->name);
205 continue;
206 }
207 diff_addremove(&revs->diffopt, '-', ce->ce_mode,
208 ce->sha1, !is_null_sha1(ce->sha1),
209 ce->name, 0);
210 continue;
211 }
212 changed = match_stat_with_submodule(&revs->diffopt, ce, &st,
213 ce_option, &dirty_submodule);
214 if (!changed && !dirty_submodule) {
215 ce_mark_uptodate(ce);
216 if (!DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
217 continue;
218 }
219 oldmode = ce->ce_mode;
220 newmode = ce_mode_from_stat(ce, st.st_mode);
221 diff_change(&revs->diffopt, oldmode, newmode,
222 ce->sha1, (changed ? null_sha1 : ce->sha1),
223 !is_null_sha1(ce->sha1), (changed ? 0 : !is_null_sha1(ce->sha1)),
224 ce->name, 0, dirty_submodule);
225 }
227 diffcore_std(&revs->diffopt);
228 diff_flush(&revs->diffopt);
229 return 0;
230}
231/*
233 * diff-index
234 */
235/* A file entry went away or appeared */
237static void diff_index_show_file(struct rev_info *revs,
238 const char *prefix,
239 const struct cache_entry *ce,
240 const unsigned char *sha1, int sha1_valid,
241 unsigned int mode,
242 unsigned dirty_submodule)
243{
244 diff_addremove(&revs->diffopt, prefix[0], mode,
245 sha1, sha1_valid, ce->name, dirty_submodule);
246}
247static int get_stat_data(const struct cache_entry *ce,
249 const unsigned char **sha1p,
250 unsigned int *modep,
251 int cached, int match_missing,
252 unsigned *dirty_submodule, struct diff_options *diffopt)
253{
254 const unsigned char *sha1 = ce->sha1;
255 unsigned int mode = ce->ce_mode;
256 if (!cached && !ce_uptodate(ce)) {
258 int changed;
259 struct stat st;
260 changed = check_removed(ce, &st);
261 if (changed < 0)
262 return -1;
263 else if (changed) {
264 if (match_missing) {
265 *sha1p = sha1;
266 *modep = mode;
267 return 0;
268 }
269 return -1;
270 }
271 changed = match_stat_with_submodule(diffopt, ce, &st,
272 0, dirty_submodule);
273 if (changed) {
274 mode = ce_mode_from_stat(ce, st.st_mode);
275 sha1 = null_sha1;
276 }
277 }
278 *sha1p = sha1;
280 *modep = mode;
281 return 0;
282}
283static void show_new_file(struct rev_info *revs,
285 const struct cache_entry *new,
286 int cached, int match_missing)
287{
288 const unsigned char *sha1;
289 unsigned int mode;
290 unsigned dirty_submodule = 0;
291 /*
293 * New file in the index: it might actually be different in
294 * the working tree.
295 */
296 if (get_stat_data(new, &sha1, &mode, cached, match_missing,
297 &dirty_submodule, &revs->diffopt) < 0)
298 return;
299 diff_index_show_file(revs, "+", new, sha1, !is_null_sha1(sha1), mode, dirty_submodule);
301}
302static int show_modified(struct rev_info *revs,
304 const struct cache_entry *old,
305 const struct cache_entry *new,
306 int report_missing,
307 int cached, int match_missing)
308{
309 unsigned int mode, oldmode;
310 const unsigned char *sha1;
311 unsigned dirty_submodule = 0;
312 if (get_stat_data(new, &sha1, &mode, cached, match_missing,
314 &dirty_submodule, &revs->diffopt) < 0) {
315 if (report_missing)
316 diff_index_show_file(revs, "-", old,
317 old->sha1, 1, old->ce_mode, 0);
318 return -1;
319 }
320 if (revs->combine_merges && !cached &&
322 (hashcmp(sha1, old->sha1) || hashcmp(old->sha1, new->sha1))) {
323 struct combine_diff_path *p;
324 int pathlen = ce_namelen(new);
325 p = xmalloc(combine_diff_path_size(2, pathlen));
327 p->path = (char *) &p->parent[2];
328 p->next = NULL;
329 memcpy(p->path, new->name, pathlen);
330 p->path[pathlen] = 0;
331 p->mode = mode;
332 hashclr(p->sha1);
333 memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
334 p->parent[0].status = DIFF_STATUS_MODIFIED;
335 p->parent[0].mode = new->ce_mode;
336 hashcpy(p->parent[0].sha1, new->sha1);
337 p->parent[1].status = DIFF_STATUS_MODIFIED;
338 p->parent[1].mode = old->ce_mode;
339 hashcpy(p->parent[1].sha1, old->sha1);
340 show_combined_diff(p, 2, revs->dense_combined_merges, revs);
341 free(p);
342 return 0;
343 }
344 oldmode = old->ce_mode;
346 if (mode == oldmode && !hashcmp(sha1, old->sha1) && !dirty_submodule &&
347 !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
348 return 0;
349 diff_change(&revs->diffopt, oldmode, mode,
351 old->sha1, sha1, 1, !is_null_sha1(sha1),
352 old->name, 0, dirty_submodule);
353 return 0;
354}
355/*
357 * This gets a mix of an existing index and a tree, one pathname entry
358 * at a time. The index entry may be a single stage-0 one, but it could
359 * also be multiple unmerged entries (in which case idx_pos/idx_nr will
360 * give you the position and number of entries in the index).
361 */
362static void do_oneway_diff(struct unpack_trees_options *o,
363 const struct cache_entry *idx,
364 const struct cache_entry *tree)
365{
366 struct rev_info *revs = o->unpack_data;
367 int match_missing, cached;
368 /* if the entry is not checked out, don't examine work tree */
370 cached = o->index_only ||
371 (idx && ((idx->ce_flags & CE_VALID) || ce_skip_worktree(idx)));
372 /*
373 * Backward compatibility wart - "diff-index -m" does
374 * not mean "do not ignore merges", but "match_missing".
375 *
376 * But with the revision flag parsing, that's found in
377 * "!revs->ignore_merges".
378 */
379 match_missing = !revs->ignore_merges;
380 if (cached && idx && ce_stage(idx)) {
382 struct diff_filepair *pair;
383 pair = diff_unmerge(&revs->diffopt, idx->name);
384 if (tree)
385 fill_filespec(pair->one, tree->sha1, 1, tree->ce_mode);
386 return;
387 }
388 /*
390 * Something added to the tree?
391 */
392 if (!tree) {
393 show_new_file(revs, idx, cached, match_missing);
394 return;
395 }
396 /*
398 * Something removed from the tree?
399 */
400 if (!idx) {
401 diff_index_show_file(revs, "-", tree, tree->sha1, 1, tree->ce_mode, 0);
402 return;
403 }
404 /* Show difference between old and new */
406 show_modified(revs, tree, idx, 1, cached, match_missing);
407}
408/*
410 * The unpack_trees() interface is designed for merging, so
411 * the different source entries are designed primarily for
412 * the source trees, with the old index being really mainly
413 * used for being replaced by the result.
414 *
415 * For diffing, the index is more important, and we only have a
416 * single tree.
417 *
418 * We're supposed to advance o->pos to skip what we have already processed.
419 *
420 * This wrapper makes it all more readable, and takes care of all
421 * the fairly complex unpack_trees() semantic requirements, including
422 * the skipping, the path matching, the type conflict cases etc.
423 */
424static int oneway_diff(const struct cache_entry * const *src,
425 struct unpack_trees_options *o)
426{
427 const struct cache_entry *idx = src[0];
428 const struct cache_entry *tree = src[1];
429 struct rev_info *revs = o->unpack_data;
430 /*
432 * Unpack-trees generates a DF/conflict entry if
433 * there was a directory in the index and a tree
434 * in the tree. From a diff standpoint, that's a
435 * delete of the tree and a create of the file.
436 */
437 if (tree == o->df_conflict_entry)
438 tree = NULL;
439 if (ce_path_match(idx ? idx : tree, &revs->prune_data, NULL)) {
441 do_oneway_diff(o, idx, tree);
442 if (diff_can_quit_early(&revs->diffopt)) {
443 o->exiting_early = 1;
444 return -1;
445 }
446 }
447 return 0;
449}
450static int diff_cache(struct rev_info *revs,
452 const unsigned char *tree_sha1,
453 const char *tree_name,
454 int cached)
455{
456 struct tree *tree;
457 struct tree_desc t;
458 struct unpack_trees_options opts;
459 tree = parse_tree_indirect(tree_sha1);
461 if (!tree)
462 return error("bad tree object %s",
463 tree_name ? tree_name : sha1_to_hex(tree_sha1));
464 memset(&opts, 0, sizeof(opts));
465 opts.head_idx = 1;
466 opts.index_only = cached;
467 opts.diff_index_cached = (cached &&
468 !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER));
469 opts.merge = 1;
470 opts.fn = oneway_diff;
471 opts.unpack_data = revs;
472 opts.src_index = &the_index;
473 opts.dst_index = NULL;
474 opts.pathspec = &revs->diffopt.pathspec;
475 opts.pathspec->recursive = 1;
476 init_tree_desc(&t, tree->buffer, tree->size);
478 return unpack_trees(1, &t, &opts);
479}
480int run_diff_index(struct rev_info *revs, int cached)
482{
483 struct object_array_entry *ent;
484 ent = revs->pending.objects;
486 if (diff_cache(revs, ent->item->sha1, ent->name, cached))
487 exit(128);
488 diff_set_mnemonic_prefix(&revs->diffopt, "c/", cached ? "i/" : "w/");
490 diffcore_fix_diff_index(&revs->diffopt);
491 diffcore_std(&revs->diffopt);
492 diff_flush(&revs->diffopt);
493 return 0;
494}
495int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
497{
498 struct rev_info revs;
499 init_revisions(&revs, NULL);
501 copy_pathspec(&revs.prune_data, &opt->pathspec);
502 revs.diffopt = *opt;
503 if (diff_cache(&revs, tree_sha1, NULL, 1))
505 exit(128);
506 return 0;
507}
508int index_differs_from(const char *def, int diff_flags)
510{
511 struct rev_info rev;
512 struct setup_revision_opt opt;
513 init_revisions(&rev, NULL);
515 memset(&opt, 0, sizeof(opt));
516 opt.def = def;
517 setup_revisions(0, NULL, &rev, &opt);
518 DIFF_OPT_SET(&rev.diffopt, QUICK);
519 DIFF_OPT_SET(&rev.diffopt, EXIT_WITH_STATUS);
520 rev.diffopt.flags |= diff_flags;
521 run_diff_index(&rev, 1);
522 if (rev.pending.alloc)
523 free(rev.pending.objects);
524 return (DIFF_OPT_TST(&rev.diffopt, HAS_CHANGES) != 0);
525}