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/*
16 * diff-files
17 */
18/*
20 * Has the work tree entity been removed?
21 *
22 * Return 1 if it was removed from the work tree, 0 if an entity to be
23 * compared with the cache entry ce still exists (the latter includes
24 * the case where a directory that is not a submodule repository
25 * exists for ce that is a submodule -- it is a submodule that is not
26 * checked out). Return negative for an error.
27 */
28static int check_removed(const struct cache_entry *ce, struct stat *st)
29{
30 if (lstat(ce->name, st) < 0) {
31 if (errno != ENOENT && errno != ENOTDIR)
32 return -1;
33 return 1;
34 }
35 if (has_symlink_leading_path(ce->name, ce_namelen(ce)))
36 return 1;
37 if (S_ISDIR(st->st_mode)) {
38 unsigned char sub[20];
39 /*
41 * If ce is already a gitlink, we can have a plain
42 * directory (i.e. the submodule is not checked out),
43 * or a checked out submodule. Either case this is not
44 * a case where something was removed from the work tree,
45 * so we will return 0.
46 *
47 * Otherwise, if the directory is not a submodule
48 * repository, that means ce which was a blob turned into
49 * a directory --- the blob was removed!
50 */
51 if (!S_ISGITLINK(ce->ce_mode) &&
52 resolve_gitlink_ref(ce->name, "HEAD", sub))
53 return 1;
54 }
55 return 0;
56}
57/*
59 * Has a file changed or has a submodule new commits or a dirty work tree?
60 *
61 * Return 1 when changes are detected, 0 otherwise. If the DIRTY_SUBMODULES
62 * option is set, the caller does not only want to know if a submodule is
63 * modified at all but wants to know all the conditions that are met (new
64 * commits, untracked content and/or modified content).
65 */
66static int match_stat_with_submodule(struct diff_options *diffopt,
67 struct cache_entry *ce, struct stat *st,
68 unsigned ce_option, unsigned *dirty_submodule)
69{
70 int changed = ce_match_stat(ce, st, ce_option);
71 if (S_ISGITLINK(ce->ce_mode)) {
72 unsigned orig_flags = diffopt->flags;
73 if (!DIFF_OPT_TST(diffopt, OVERRIDE_SUBMODULE_CONFIG))
74 set_diffopt_flags_from_submodule_config(diffopt, ce->name);
75 if (DIFF_OPT_TST(diffopt, IGNORE_SUBMODULES))
76 changed = 0;
77 else if (!DIFF_OPT_TST(diffopt, IGNORE_DIRTY_SUBMODULES)
78 && (!changed || DIFF_OPT_TST(diffopt, DIRTY_SUBMODULES)))
79 *dirty_submodule = is_submodule_modified(ce->name, DIFF_OPT_TST(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES));
80 diffopt->flags = orig_flags;
81 }
82 return changed;
83}
84int run_diff_files(struct rev_info *revs, unsigned int option)
86{
87 int entries, i;
88 int diff_unmerged_stage = revs->max_count;
89 int silent_on_removed = option & DIFF_SILENT_ON_REMOVED;
90 unsigned ce_option = ((option & DIFF_RACY_IS_MODIFIED)
91 ? CE_MATCH_RACY_IS_DIRTY : 0);
92 diff_set_mnemonic_prefix(&revs->diffopt, "i/", "w/");
94 if (diff_unmerged_stage < 0)
96 diff_unmerged_stage = 2;
97 entries = active_nr;
98 for (i = 0; i < entries; i++) {
99 struct stat st;
100 unsigned int oldmode, newmode;
101 struct cache_entry *ce = active_cache[i];
102 int changed;
103 unsigned dirty_submodule = 0;
104 if (DIFF_OPT_TST(&revs->diffopt, QUICK) &&
106 !revs->diffopt.filter &&
107 DIFF_OPT_TST(&revs->diffopt, HAS_CHANGES))
108 break;
109 if (!ce_path_match(ce, &revs->prune_data))
111 continue;
112 if (ce_stage(ce)) {
114 struct combine_diff_path *dpath;
115 struct diff_filepair *pair;
116 unsigned int wt_mode = 0;
117 int num_compare_stages = 0;
118 size_t path_len;
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 dpath->len = path_len;
127 memcpy(dpath->path, ce->name, path_len);
128 dpath->path[path_len] = '\0';
129 hashclr(dpath->sha1);
130 memset(&(dpath->parent[0]), 0,
131 sizeof(struct combine_diff_parent)*5);
132 changed = check_removed(ce, &st);
134 if (!changed)
135 wt_mode = ce_mode_from_stat(ce, st.st_mode);
136 else {
137 if (changed < 0) {
138 perror(ce->name);
139 continue;
140 }
141 if (silent_on_removed)
142 continue;
143 wt_mode = 0;
144 }
145 dpath->mode = wt_mode;
146 while (i < entries) {
148 struct cache_entry *nce = active_cache[i];
149 int stage;
150 if (strcmp(ce->name, nce->name))
152 break;
153 /* Stage #2 (ours) is the first parent,
155 * stage #3 (theirs) is the second.
156 */
157 stage = ce_stage(nce);
158 if (2 <= stage) {
159 int mode = nce->ce_mode;
160 num_compare_stages++;
161 hashcpy(dpath->parent[stage-2].sha1, nce->sha1);
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(dpath);
185 dpath = NULL;
186 /*
188 * Show the diff for the 'ce' if we found the one
189 * from the desired stage.
190 */
191 pair = diff_unmerge(&revs->diffopt, ce->name);
192 if (wt_mode)
193 pair->two->mode = wt_mode;
194 if (ce_stage(ce) != diff_unmerged_stage)
195 continue;
196 }
197 if (ce_uptodate(ce) || ce_skip_worktree(ce))
199 continue;
200 /* If CE_VALID is set, don't look at workdir for file removal */
202 changed = (ce->ce_flags & CE_VALID) ? 0 : check_removed(ce, &st);
203 if (changed) {
204 if (changed < 0) {
205 perror(ce->name);
206 continue;
207 }
208 if (silent_on_removed)
209 continue;
210 diff_addremove(&revs->diffopt, '-', ce->ce_mode,
211 ce->sha1, ce->name, 0);
212 continue;
213 }
214 changed = match_stat_with_submodule(&revs->diffopt, ce, &st,
215 ce_option, &dirty_submodule);
216 if (!changed && !dirty_submodule) {
217 ce_mark_uptodate(ce);
218 if (!DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
219 continue;
220 }
221 oldmode = ce->ce_mode;
222 newmode = ce_mode_from_stat(ce, st.st_mode);
223 diff_change(&revs->diffopt, oldmode, newmode,
224 ce->sha1, (changed ? null_sha1 : ce->sha1),
225 ce->name, 0, dirty_submodule);
226 }
228 diffcore_std(&revs->diffopt);
229 diff_flush(&revs->diffopt);
230 return 0;
231}
232/*
234 * diff-index
235 */
236/* A file entry went away or appeared */
238static void diff_index_show_file(struct rev_info *revs,
239 const char *prefix,
240 struct cache_entry *ce,
241 const unsigned char *sha1, unsigned int mode,
242 unsigned dirty_submodule)
243{
244 diff_addremove(&revs->diffopt, prefix[0], mode,
245 sha1, ce->name, dirty_submodule);
246}
247static int get_stat_data(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 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 copy.
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, mode, dirty_submodule);
301}
302static int show_modified(struct rev_info *revs,
304 struct cache_entry *old,
305 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, 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 p->len = pathlen;
330 memcpy(p->path, new->name, pathlen);
331 p->path[pathlen] = 0;
332 p->mode = mode;
333 hashclr(p->sha1);
334 memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
335 p->parent[0].status = DIFF_STATUS_MODIFIED;
336 p->parent[0].mode = new->ce_mode;
337 hashcpy(p->parent[0].sha1, new->sha1);
338 p->parent[1].status = DIFF_STATUS_MODIFIED;
339 p->parent[1].mode = old->ce_mode;
340 hashcpy(p->parent[1].sha1, old->sha1);
341 show_combined_diff(p, 2, revs->dense_combined_merges, revs);
342 free(p);
343 return 0;
344 }
345 oldmode = old->ce_mode;
347 if (mode == oldmode && !hashcmp(sha1, old->sha1) && !dirty_submodule &&
348 !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
349 return 0;
350 diff_change(&revs->diffopt, oldmode, mode,
352 old->sha1, sha1, 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 struct cache_entry *idx,
364 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 fill_filespec(pair->one, idx->sha1, idx->ce_mode);
385 return;
386 }
387 /*
389 * Something added to the tree?
390 */
391 if (!tree) {
392 show_new_file(revs, idx, cached, match_missing);
393 return;
394 }
395 /*
397 * Something removed from the tree?
398 */
399 if (!idx) {
400 diff_index_show_file(revs, "-", tree, tree->sha1, tree->ce_mode, 0);
401 return;
402 }
403 /* Show difference between old and new */
405 show_modified(revs, tree, idx, 1, cached, match_missing);
406}
407/*
409 * The unpack_trees() interface is designed for merging, so
410 * the different source entries are designed primarily for
411 * the source trees, with the old index being really mainly
412 * used for being replaced by the result.
413 *
414 * For diffing, the index is more important, and we only have a
415 * single tree.
416 *
417 * We're supposed to advance o->pos to skip what we have already processed.
418 *
419 * This wrapper makes it all more readable, and takes care of all
420 * the fairly complex unpack_trees() semantic requirements, including
421 * the skipping, the path matching, the type conflict cases etc.
422 */
423static int oneway_diff(struct cache_entry **src, struct unpack_trees_options *o)
424{
425 struct cache_entry *idx = src[0];
426 struct cache_entry *tree = src[1];
427 struct rev_info *revs = o->unpack_data;
428 /*
430 * Unpack-trees generates a DF/conflict entry if
431 * there was a directory in the index and a tree
432 * in the tree. From a diff standpoint, that's a
433 * delete of the tree and a create of the file.
434 */
435 if (tree == o->df_conflict_entry)
436 tree = NULL;
437 if (ce_path_match(idx ? idx : tree, &revs->prune_data))
439 do_oneway_diff(o, idx, tree);
440 return 0;
442}
443int run_diff_index(struct rev_info *revs, int cached)
445{
446 struct object *ent;
447 struct tree *tree;
448 const char *tree_name;
449 struct unpack_trees_options opts;
450 struct tree_desc t;
451 ent = revs->pending.objects[0].item;
453 tree_name = revs->pending.objects[0].name;
454 tree = parse_tree_indirect(ent->sha1);
455 if (!tree)
456 return error("bad tree object %s", tree_name);
457 memset(&opts, 0, sizeof(opts));
459 opts.head_idx = 1;
460 opts.index_only = cached;
461 opts.diff_index_cached = (cached &&
462 !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER));
463 opts.merge = 1;
464 opts.fn = oneway_diff;
465 opts.unpack_data = revs;
466 opts.src_index = &the_index;
467 opts.dst_index = NULL;
468 init_tree_desc(&t, tree->buffer, tree->size);
470 if (unpack_trees(1, &t, &opts))
471 exit(128);
472 diff_set_mnemonic_prefix(&revs->diffopt, "c/", cached ? "i/" : "w/");
474 diffcore_fix_diff_index(&revs->diffopt);
475 diffcore_std(&revs->diffopt);
476 diff_flush(&revs->diffopt);
477 return 0;
478}
479int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
481{
482 struct tree *tree;
483 struct rev_info revs;
484 int i;
485 struct cache_entry **dst;
486 struct cache_entry *last = NULL;
487 struct unpack_trees_options opts;
488 struct tree_desc t;
489 /*
491 * This is used by git-blame to run diff-cache internally;
492 * it potentially needs to repeatedly run this, so we will
493 * start by removing the higher order entries the last round
494 * left behind.
495 */
496 dst = active_cache;
497 for (i = 0; i < active_nr; i++) {
498 struct cache_entry *ce = active_cache[i];
499 if (ce_stage(ce)) {
500 if (last && !strcmp(ce->name, last->name))
501 continue;
502 cache_tree_invalidate_path(active_cache_tree,
503 ce->name);
504 last = ce;
505 ce->ce_flags |= CE_REMOVE;
506 }
507 *dst++ = ce;
508 }
509 active_nr = dst - active_cache;
510 init_revisions(&revs, NULL);
512 init_pathspec(&revs.prune_data, opt->pathspec.raw);
513 tree = parse_tree_indirect(tree_sha1);
514 if (!tree)
515 die("bad tree object %s", sha1_to_hex(tree_sha1));
516 memset(&opts, 0, sizeof(opts));
518 opts.head_idx = 1;
519 opts.index_only = 1;
520 opts.diff_index_cached = !DIFF_OPT_TST(opt, FIND_COPIES_HARDER);
521 opts.merge = 1;
522 opts.fn = oneway_diff;
523 opts.unpack_data = &revs;
524 opts.src_index = &the_index;
525 opts.dst_index = &the_index;
526 init_tree_desc(&t, tree->buffer, tree->size);
528 if (unpack_trees(1, &t, &opts))
529 exit(128);
530 return 0;
531}
532int index_differs_from(const char *def, int diff_flags)
534{
535 struct rev_info rev;
536 struct setup_revision_opt opt;
537 init_revisions(&rev, NULL);
539 memset(&opt, 0, sizeof(opt));
540 opt.def = def;
541 setup_revisions(0, NULL, &rev, &opt);
542 DIFF_OPT_SET(&rev.diffopt, QUICK);
543 DIFF_OPT_SET(&rev.diffopt, EXIT_WITH_STATUS);
544 rev.diffopt.flags |= diff_flags;
545 run_diff_index(&rev, 1);
546 if (rev.pending.alloc)
547 free(rev.pending.objects);
548 return (DIFF_OPT_TST(&rev.diffopt, HAS_CHANGES) != 0);
549}