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#include "fsmonitor.h"
16/*
18 * diff-files
19 */
20/*
22 * Has the work tree entity been removed?
23 *
24 * Return 1 if it was removed from the work tree, 0 if an entity to be
25 * compared with the cache entry ce still exists (the latter includes
26 * the case where a directory that is not a submodule repository
27 * exists for ce that is a submodule -- it is a submodule that is not
28 * checked out). Return negative for an error.
29 */
30static int check_removed(const struct cache_entry *ce, struct stat *st)
31{
32 if (lstat(ce->name, st) < 0) {
33 if (!is_missing_file_error(errno))
34 return -1;
35 return 1;
36 }
37 if (has_symlink_leading_path(ce->name, ce_namelen(ce)))
38 return 1;
39 if (S_ISDIR(st->st_mode)) {
40 struct object_id sub;
41 /*
43 * If ce is already a gitlink, we can have a plain
44 * directory (i.e. the submodule is not checked out),
45 * or a checked out submodule. Either case this is not
46 * a case where something was removed from the work tree,
47 * so we will return 0.
48 *
49 * Otherwise, if the directory is not a submodule
50 * repository, that means ce which was a blob turned into
51 * a directory --- the blob was removed!
52 */
53 if (!S_ISGITLINK(ce->ce_mode) &&
54 resolve_gitlink_ref(ce->name, "HEAD", &sub))
55 return 1;
56 }
57 return 0;
58}
59/*
61 * Has a file changed or has a submodule new commits or a dirty work tree?
62 *
63 * Return 1 when changes are detected, 0 otherwise. If the DIRTY_SUBMODULES
64 * option is set, the caller does not only want to know if a submodule is
65 * modified at all but wants to know all the conditions that are met (new
66 * commits, untracked content and/or modified content).
67 */
68static int match_stat_with_submodule(struct diff_options *diffopt,
69 const struct cache_entry *ce,
70 struct stat *st, unsigned ce_option,
71 unsigned *dirty_submodule)
72{
73 int changed = ce_match_stat(ce, st, ce_option);
74 if (S_ISGITLINK(ce->ce_mode)) {
75 struct diff_flags orig_flags = diffopt->flags;
76 if (!diffopt->flags.override_submodule_config)
77 set_diffopt_flags_from_submodule_config(diffopt, ce->name);
78 if (diffopt->flags.ignore_submodules)
79 changed = 0;
80 else if (!diffopt->flags.ignore_dirty_submodules &&
81 (!changed || diffopt->flags.dirty_submodules))
82 *dirty_submodule = is_submodule_modified(ce->name,
83 diffopt->flags.ignore_untracked_in_submodules);
84 diffopt->flags = orig_flags;
85 }
86 return changed;
87}
88int run_diff_files(struct rev_info *revs, unsigned int option)
90{
91 int entries, i;
92 int diff_unmerged_stage = revs->max_count;
93 unsigned ce_option = ((option & DIFF_RACY_IS_MODIFIED)
94 ? CE_MATCH_RACY_IS_DIRTY : 0);
95 diff_set_mnemonic_prefix(&revs->diffopt, "i/", "w/");
97 if (diff_unmerged_stage < 0)
99 diff_unmerged_stage = 2;
100 entries = active_nr;
101 for (i = 0; i < entries; i++) {
102 unsigned int oldmode, newmode;
103 struct cache_entry *ce = active_cache[i];
104 int changed;
105 unsigned dirty_submodule = 0;
106 const struct object_id *old_oid, *new_oid;
107 if (diff_can_quit_early(&revs->diffopt))
109 break;
110 if (!ce_path_match(ce, &revs->prune_data, NULL))
112 continue;
113 if (ce_stage(ce)) {
115 struct combine_diff_path *dpath;
116 struct diff_filepair *pair;
117 unsigned int wt_mode = 0;
118 int num_compare_stages = 0;
119 size_t path_len;
120 struct stat st;
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 oidclr(&dpath->oid);
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 oidcpy(&dpath->parent[stage - 2].oid,
161 &nce->oid);
162 dpath->parent[stage-2].mode = ce_mode_from_stat(nce, mode);
163 dpath->parent[stage-2].status =
164 DIFF_STATUS_MODIFIED;
165 }
166 /* diff against the proper unmerged stage */
168 if (stage == diff_unmerged_stage)
169 ce = nce;
170 i++;
171 }
172 /*
173 * Compensate for loop update
174 */
175 i--;
176 if (revs->combine_merges && num_compare_stages == 2) {
178 show_combined_diff(dpath, 2,
179 revs->dense_combined_merges,
180 revs);
181 free(dpath);
182 continue;
183 }
184 FREE_AND_NULL(dpath);
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 if (ce->ce_flags & CE_VALID) {
202 changed = 0;
203 newmode = ce->ce_mode;
204 } else {
205 struct stat st;
206 changed = check_removed(ce, &st);
208 if (changed) {
209 if (changed < 0) {
210 perror(ce->name);
211 continue;
212 }
213 diff_addremove(&revs->diffopt, '-', ce->ce_mode,
214 &ce->oid,
215 !is_null_oid(&ce->oid),
216 ce->name, 0);
217 continue;
218 } else if (revs->diffopt.ita_invisible_in_index &&
219 ce_intent_to_add(ce)) {
220 diff_addremove(&revs->diffopt, '+', ce->ce_mode,
221 the_hash_algo->empty_tree, 0,
222 ce->name, 0);
223 continue;
224 }
225 changed = match_stat_with_submodule(&revs->diffopt, ce, &st,
227 ce_option, &dirty_submodule);
228 newmode = ce_mode_from_stat(ce, st.st_mode);
229 }
230 if (!changed && !dirty_submodule) {
232 ce_mark_uptodate(ce);
233 mark_fsmonitor_valid(ce);
234 if (!revs->diffopt.flags.find_copies_harder)
235 continue;
236 }
237 oldmode = ce->ce_mode;
238 old_oid = &ce->oid;
239 new_oid = changed ? &null_oid : &ce->oid;
240 diff_change(&revs->diffopt, oldmode, newmode,
241 old_oid, new_oid,
242 !is_null_oid(old_oid),
243 !is_null_oid(new_oid),
244 ce->name, 0, dirty_submodule);
245 }
247 diffcore_std(&revs->diffopt);
248 diff_flush(&revs->diffopt);
249 return 0;
250}
251/*
253 * diff-index
254 */
255/* A file entry went away or appeared */
257static void diff_index_show_file(struct rev_info *revs,
258 const char *prefix,
259 const struct cache_entry *ce,
260 const struct object_id *oid, int oid_valid,
261 unsigned int mode,
262 unsigned dirty_submodule)
263{
264 diff_addremove(&revs->diffopt, prefix[0], mode,
265 oid, oid_valid, ce->name, dirty_submodule);
266}
267static int get_stat_data(const struct cache_entry *ce,
269 const struct object_id **oidp,
270 unsigned int *modep,
271 int cached, int match_missing,
272 unsigned *dirty_submodule, struct diff_options *diffopt)
273{
274 const struct object_id *oid = &ce->oid;
275 unsigned int mode = ce->ce_mode;
276 if (!cached && !ce_uptodate(ce)) {
278 int changed;
279 struct stat st;
280 changed = check_removed(ce, &st);
281 if (changed < 0)
282 return -1;
283 else if (changed) {
284 if (match_missing) {
285 *oidp = oid;
286 *modep = mode;
287 return 0;
288 }
289 return -1;
290 }
291 changed = match_stat_with_submodule(diffopt, ce, &st,
292 0, dirty_submodule);
293 if (changed) {
294 mode = ce_mode_from_stat(ce, st.st_mode);
295 oid = &null_oid;
296 }
297 }
298 *oidp = oid;
300 *modep = mode;
301 return 0;
302}
303static void show_new_file(struct rev_info *revs,
305 const struct cache_entry *new,
306 int cached, int match_missing)
307{
308 const struct object_id *oid;
309 unsigned int mode;
310 unsigned dirty_submodule = 0;
311 /*
313 * New file in the index: it might actually be different in
314 * the working tree.
315 */
316 if (get_stat_data(new, &oid, &mode, cached, match_missing,
317 &dirty_submodule, &revs->diffopt) < 0)
318 return;
319 diff_index_show_file(revs, "+", new, oid, !is_null_oid(oid), mode, dirty_submodule);
321}
322static int show_modified(struct rev_info *revs,
324 const struct cache_entry *old,
325 const struct cache_entry *new,
326 int report_missing,
327 int cached, int match_missing)
328{
329 unsigned int mode, oldmode;
330 const struct object_id *oid;
331 unsigned dirty_submodule = 0;
332 if (get_stat_data(new, &oid, &mode, cached, match_missing,
334 &dirty_submodule, &revs->diffopt) < 0) {
335 if (report_missing)
336 diff_index_show_file(revs, "-", old,
337 &old->oid, 1, old->ce_mode,
338 0);
339 return -1;
340 }
341 if (revs->combine_merges && !cached &&
343 (oidcmp(oid, &old->oid) || oidcmp(&old->oid, &new->oid))) {
344 struct combine_diff_path *p;
345 int pathlen = ce_namelen(new);
346 p = xmalloc(combine_diff_path_size(2, pathlen));
348 p->path = (char *) &p->parent[2];
349 p->next = NULL;
350 memcpy(p->path, new->name, pathlen);
351 p->path[pathlen] = 0;
352 p->mode = mode;
353 oidclr(&p->oid);
354 memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
355 p->parent[0].status = DIFF_STATUS_MODIFIED;
356 p->parent[0].mode = new->ce_mode;
357 oidcpy(&p->parent[0].oid, &new->oid);
358 p->parent[1].status = DIFF_STATUS_MODIFIED;
359 p->parent[1].mode = old->ce_mode;
360 oidcpy(&p->parent[1].oid, &old->oid);
361 show_combined_diff(p, 2, revs->dense_combined_merges, revs);
362 free(p);
363 return 0;
364 }
365 oldmode = old->ce_mode;
367 if (mode == oldmode && !oidcmp(oid, &old->oid) && !dirty_submodule &&
368 !revs->diffopt.flags.find_copies_harder)
369 return 0;
370 diff_change(&revs->diffopt, oldmode, mode,
372 &old->oid, oid, 1, !is_null_oid(oid),
373 old->name, 0, dirty_submodule);
374 return 0;
375}
376/*
378 * This gets a mix of an existing index and a tree, one pathname entry
379 * at a time. The index entry may be a single stage-0 one, but it could
380 * also be multiple unmerged entries (in which case idx_pos/idx_nr will
381 * give you the position and number of entries in the index).
382 */
383static void do_oneway_diff(struct unpack_trees_options *o,
384 const struct cache_entry *idx,
385 const struct cache_entry *tree)
386{
387 struct rev_info *revs = o->unpack_data;
388 int match_missing, cached;
389 /* i-t-a entries do not actually exist in the index */
391 if (revs->diffopt.ita_invisible_in_index &&
392 idx && ce_intent_to_add(idx)) {
393 idx = NULL;
394 if (!tree)
395 return; /* nothing to diff.. */
396 }
397 /* if the entry is not checked out, don't examine work tree */
399 cached = o->index_only ||
400 (idx && ((idx->ce_flags & CE_VALID) || ce_skip_worktree(idx)));
401 /*
402 * Backward compatibility wart - "diff-index -m" does
403 * not mean "do not ignore merges", but "match_missing".
404 *
405 * But with the revision flag parsing, that's found in
406 * "!revs->ignore_merges".
407 */
408 match_missing = !revs->ignore_merges;
409 if (cached && idx && ce_stage(idx)) {
411 struct diff_filepair *pair;
412 pair = diff_unmerge(&revs->diffopt, idx->name);
413 if (tree)
414 fill_filespec(pair->one, &tree->oid, 1,
415 tree->ce_mode);
416 return;
417 }
418 /*
420 * Something added to the tree?
421 */
422 if (!tree) {
423 show_new_file(revs, idx, cached, match_missing);
424 return;
425 }
426 /*
428 * Something removed from the tree?
429 */
430 if (!idx) {
431 diff_index_show_file(revs, "-", tree, &tree->oid, 1,
432 tree->ce_mode, 0);
433 return;
434 }
435 /* Show difference between old and new */
437 show_modified(revs, tree, idx, 1, cached, match_missing);
438}
439/*
441 * The unpack_trees() interface is designed for merging, so
442 * the different source entries are designed primarily for
443 * the source trees, with the old index being really mainly
444 * used for being replaced by the result.
445 *
446 * For diffing, the index is more important, and we only have a
447 * single tree.
448 *
449 * We're supposed to advance o->pos to skip what we have already processed.
450 *
451 * This wrapper makes it all more readable, and takes care of all
452 * the fairly complex unpack_trees() semantic requirements, including
453 * the skipping, the path matching, the type conflict cases etc.
454 */
455static int oneway_diff(const struct cache_entry * const *src,
456 struct unpack_trees_options *o)
457{
458 const struct cache_entry *idx = src[0];
459 const struct cache_entry *tree = src[1];
460 struct rev_info *revs = o->unpack_data;
461 /*
463 * Unpack-trees generates a DF/conflict entry if
464 * there was a directory in the index and a tree
465 * in the tree. From a diff standpoint, that's a
466 * delete of the tree and a create of the file.
467 */
468 if (tree == o->df_conflict_entry)
469 tree = NULL;
470 if (ce_path_match(idx ? idx : tree, &revs->prune_data, NULL)) {
472 do_oneway_diff(o, idx, tree);
473 if (diff_can_quit_early(&revs->diffopt)) {
474 o->exiting_early = 1;
475 return -1;
476 }
477 }
478 return 0;
480}
481static int diff_cache(struct rev_info *revs,
483 const struct object_id *tree_oid,
484 const char *tree_name,
485 int cached)
486{
487 struct tree *tree;
488 struct tree_desc t;
489 struct unpack_trees_options opts;
490 tree = parse_tree_indirect(tree_oid);
492 if (!tree)
493 return error("bad tree object %s",
494 tree_name ? tree_name : oid_to_hex(tree_oid));
495 memset(&opts, 0, sizeof(opts));
496 opts.head_idx = 1;
497 opts.index_only = cached;
498 opts.diff_index_cached = (cached &&
499 !revs->diffopt.flags.find_copies_harder);
500 opts.merge = 1;
501 opts.fn = oneway_diff;
502 opts.unpack_data = revs;
503 opts.src_index = &the_index;
504 opts.dst_index = NULL;
505 opts.pathspec = &revs->diffopt.pathspec;
506 opts.pathspec->recursive = 1;
507 init_tree_desc(&t, tree->buffer, tree->size);
509 return unpack_trees(1, &t, &opts);
510}
511int run_diff_index(struct rev_info *revs, int cached)
513{
514 struct object_array_entry *ent;
515 ent = revs->pending.objects;
517 if (diff_cache(revs, &ent->item->oid, ent->name, cached))
518 exit(128);
519 diff_set_mnemonic_prefix(&revs->diffopt, "c/", cached ? "i/" : "w/");
521 diffcore_fix_diff_index(&revs->diffopt);
522 diffcore_std(&revs->diffopt);
523 diff_flush(&revs->diffopt);
524 return 0;
525}
526int do_diff_cache(const struct object_id *tree_oid, struct diff_options *opt)
528{
529 struct rev_info revs;
530 init_revisions(&revs, NULL);
532 copy_pathspec(&revs.prune_data, &opt->pathspec);
533 revs.diffopt = *opt;
534 if (diff_cache(&revs, tree_oid, NULL, 1))
536 exit(128);
537 return 0;
538}
539int index_differs_from(const char *def, const struct diff_flags *flags,
541 int ita_invisible_in_index)
542{
543 struct rev_info rev;
544 struct setup_revision_opt opt;
545 init_revisions(&rev, NULL);
547 memset(&opt, 0, sizeof(opt));
548 opt.def = def;
549 setup_revisions(0, NULL, &rev, &opt);
550 rev.diffopt.flags.quick = 1;
551 rev.diffopt.flags.exit_with_status = 1;
552 if (flags)
553 diff_flags_or(&rev.diffopt.flags, flags);
554 rev.diffopt.ita_invisible_in_index = ita_invisible_in_index;
555 run_diff_index(&rev, 1);
556 object_array_clear(&rev.pending);
557 return (rev.diffopt.flags.has_changes != 0);
558}