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 const struct cache_entry *ce,
68 struct stat *st, unsigned ce_option,
69 unsigned *dirty_submodule)
70{
71 int changed = ce_match_stat(ce, st, ce_option);
72 if (S_ISGITLINK(ce->ce_mode)) {
73 unsigned orig_flags = diffopt->flags;
74 if (!DIFF_OPT_TST(diffopt, OVERRIDE_SUBMODULE_CONFIG))
75 set_diffopt_flags_from_submodule_config(diffopt, ce->name);
76 if (DIFF_OPT_TST(diffopt, IGNORE_SUBMODULES))
77 changed = 0;
78 else if (!DIFF_OPT_TST(diffopt, IGNORE_DIRTY_SUBMODULES)
79 && (!changed || DIFF_OPT_TST(diffopt, DIRTY_SUBMODULES)))
80 *dirty_submodule = is_submodule_modified(ce->name, DIFF_OPT_TST(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES));
81 diffopt->flags = orig_flags;
82 }
83 return changed;
84}
85int run_diff_files(struct rev_info *revs, unsigned int option)
87{
88 int entries, i;
89 int diff_unmerged_stage = revs->max_count;
90 int silent_on_removed = option & DIFF_SILENT_ON_REMOVED;
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 struct stat st;
101 unsigned int oldmode, newmode;
102 struct cache_entry *ce = active_cache[i];
103 int changed;
104 unsigned dirty_submodule = 0;
105 if (diff_can_quit_early(&revs->diffopt))
107 break;
108 if (!ce_path_match(ce, &revs->prune_data))
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 path_len = ce_namelen(ce);
120 dpath = xmalloc(combine_diff_path_size(5, path_len));
122 dpath->path = (char *) &(dpath->parent[5]);
123 dpath->next = NULL;
125 dpath->len = path_len;
126 memcpy(dpath->path, ce->name, path_len);
127 dpath->path[path_len] = '\0';
128 hashclr(dpath->sha1);
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 if (silent_on_removed)
141 continue;
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 if (silent_on_removed)
208 continue;
209 diff_addremove(&revs->diffopt, '-', ce->ce_mode,
210 ce->sha1, !is_null_sha1(ce->sha1),
211 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 !is_null_sha1(ce->sha1), (changed ? 0 : !is_null_sha1(ce->sha1)),
226 ce->name, 0, dirty_submodule);
227 }
229 diffcore_std(&revs->diffopt);
230 diff_flush(&revs->diffopt);
231 return 0;
232}
233/*
235 * diff-index
236 */
237/* A file entry went away or appeared */
239static void diff_index_show_file(struct rev_info *revs,
240 const char *prefix,
241 const struct cache_entry *ce,
242 const unsigned char *sha1, int sha1_valid,
243 unsigned int mode,
244 unsigned dirty_submodule)
245{
246 diff_addremove(&revs->diffopt, prefix[0], mode,
247 sha1, sha1_valid, ce->name, dirty_submodule);
248}
249static int get_stat_data(const struct cache_entry *ce,
251 const unsigned char **sha1p,
252 unsigned int *modep,
253 int cached, int match_missing,
254 unsigned *dirty_submodule, struct diff_options *diffopt)
255{
256 const unsigned char *sha1 = ce->sha1;
257 unsigned int mode = ce->ce_mode;
258 if (!cached && !ce_uptodate(ce)) {
260 int changed;
261 struct stat st;
262 changed = check_removed(ce, &st);
263 if (changed < 0)
264 return -1;
265 else if (changed) {
266 if (match_missing) {
267 *sha1p = sha1;
268 *modep = mode;
269 return 0;
270 }
271 return -1;
272 }
273 changed = match_stat_with_submodule(diffopt, ce, &st,
274 0, dirty_submodule);
275 if (changed) {
276 mode = ce_mode_from_stat(ce, st.st_mode);
277 sha1 = null_sha1;
278 }
279 }
280 *sha1p = sha1;
282 *modep = mode;
283 return 0;
284}
285static void show_new_file(struct rev_info *revs,
287 const struct cache_entry *new,
288 int cached, int match_missing)
289{
290 const unsigned char *sha1;
291 unsigned int mode;
292 unsigned dirty_submodule = 0;
293 /*
295 * New file in the index: it might actually be different in
296 * the working tree.
297 */
298 if (get_stat_data(new, &sha1, &mode, cached, match_missing,
299 &dirty_submodule, &revs->diffopt) < 0)
300 return;
301 diff_index_show_file(revs, "+", new, sha1, !is_null_sha1(sha1), mode, dirty_submodule);
303}
304static int show_modified(struct rev_info *revs,
306 const struct cache_entry *old,
307 const struct cache_entry *new,
308 int report_missing,
309 int cached, int match_missing)
310{
311 unsigned int mode, oldmode;
312 const unsigned char *sha1;
313 unsigned dirty_submodule = 0;
314 if (get_stat_data(new, &sha1, &mode, cached, match_missing,
316 &dirty_submodule, &revs->diffopt) < 0) {
317 if (report_missing)
318 diff_index_show_file(revs, "-", old,
319 old->sha1, 1, old->ce_mode, 0);
320 return -1;
321 }
322 if (revs->combine_merges && !cached &&
324 (hashcmp(sha1, old->sha1) || hashcmp(old->sha1, new->sha1))) {
325 struct combine_diff_path *p;
326 int pathlen = ce_namelen(new);
327 p = xmalloc(combine_diff_path_size(2, pathlen));
329 p->path = (char *) &p->parent[2];
330 p->next = NULL;
331 p->len = pathlen;
332 memcpy(p->path, new->name, pathlen);
333 p->path[pathlen] = 0;
334 p->mode = mode;
335 hashclr(p->sha1);
336 memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
337 p->parent[0].status = DIFF_STATUS_MODIFIED;
338 p->parent[0].mode = new->ce_mode;
339 hashcpy(p->parent[0].sha1, new->sha1);
340 p->parent[1].status = DIFF_STATUS_MODIFIED;
341 p->parent[1].mode = old->ce_mode;
342 hashcpy(p->parent[1].sha1, old->sha1);
343 show_combined_diff(p, 2, revs->dense_combined_merges, revs);
344 free(p);
345 return 0;
346 }
347 oldmode = old->ce_mode;
349 if (mode == oldmode && !hashcmp(sha1, old->sha1) && !dirty_submodule &&
350 !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
351 return 0;
352 diff_change(&revs->diffopt, oldmode, mode,
354 old->sha1, sha1, 1, !is_null_sha1(sha1),
355 old->name, 0, dirty_submodule);
356 return 0;
357}
358/*
360 * This gets a mix of an existing index and a tree, one pathname entry
361 * at a time. The index entry may be a single stage-0 one, but it could
362 * also be multiple unmerged entries (in which case idx_pos/idx_nr will
363 * give you the position and number of entries in the index).
364 */
365static void do_oneway_diff(struct unpack_trees_options *o,
366 const struct cache_entry *idx,
367 const struct cache_entry *tree)
368{
369 struct rev_info *revs = o->unpack_data;
370 int match_missing, cached;
371 /* if the entry is not checked out, don't examine work tree */
373 cached = o->index_only ||
374 (idx && ((idx->ce_flags & CE_VALID) || ce_skip_worktree(idx)));
375 /*
376 * Backward compatibility wart - "diff-index -m" does
377 * not mean "do not ignore merges", but "match_missing".
378 *
379 * But with the revision flag parsing, that's found in
380 * "!revs->ignore_merges".
381 */
382 match_missing = !revs->ignore_merges;
383 if (cached && idx && ce_stage(idx)) {
385 struct diff_filepair *pair;
386 pair = diff_unmerge(&revs->diffopt, idx->name);
387 if (tree)
388 fill_filespec(pair->one, tree->sha1, 1, tree->ce_mode);
389 return;
390 }
391 /*
393 * Something added to the tree?
394 */
395 if (!tree) {
396 show_new_file(revs, idx, cached, match_missing);
397 return;
398 }
399 /*
401 * Something removed from the tree?
402 */
403 if (!idx) {
404 diff_index_show_file(revs, "-", tree, tree->sha1, 1, tree->ce_mode, 0);
405 return;
406 }
407 /* Show difference between old and new */
409 show_modified(revs, tree, idx, 1, cached, match_missing);
410}
411/*
413 * The unpack_trees() interface is designed for merging, so
414 * the different source entries are designed primarily for
415 * the source trees, with the old index being really mainly
416 * used for being replaced by the result.
417 *
418 * For diffing, the index is more important, and we only have a
419 * single tree.
420 *
421 * We're supposed to advance o->pos to skip what we have already processed.
422 *
423 * This wrapper makes it all more readable, and takes care of all
424 * the fairly complex unpack_trees() semantic requirements, including
425 * the skipping, the path matching, the type conflict cases etc.
426 */
427static int oneway_diff(const struct cache_entry * const *src,
428 struct unpack_trees_options *o)
429{
430 const struct cache_entry *idx = src[0];
431 const struct cache_entry *tree = src[1];
432 struct rev_info *revs = o->unpack_data;
433 /*
435 * Unpack-trees generates a DF/conflict entry if
436 * there was a directory in the index and a tree
437 * in the tree. From a diff standpoint, that's a
438 * delete of the tree and a create of the file.
439 */
440 if (tree == o->df_conflict_entry)
441 tree = NULL;
442 if (ce_path_match(idx ? idx : tree, &revs->prune_data)) {
444 do_oneway_diff(o, idx, tree);
445 if (diff_can_quit_early(&revs->diffopt)) {
446 o->exiting_early = 1;
447 return -1;
448 }
449 }
450 return 0;
452}
453static int diff_cache(struct rev_info *revs,
455 const unsigned char *tree_sha1,
456 const char *tree_name,
457 int cached)
458{
459 struct tree *tree;
460 struct tree_desc t;
461 struct unpack_trees_options opts;
462 tree = parse_tree_indirect(tree_sha1);
464 if (!tree)
465 return error("bad tree object %s",
466 tree_name ? tree_name : sha1_to_hex(tree_sha1));
467 memset(&opts, 0, sizeof(opts));
468 opts.head_idx = 1;
469 opts.index_only = cached;
470 opts.diff_index_cached = (cached &&
471 !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER));
472 opts.merge = 1;
473 opts.fn = oneway_diff;
474 opts.unpack_data = revs;
475 opts.src_index = &the_index;
476 opts.dst_index = NULL;
477 opts.pathspec = &revs->diffopt.pathspec;
478 opts.pathspec->recursive = 1;
479 init_tree_desc(&t, tree->buffer, tree->size);
481 return unpack_trees(1, &t, &opts);
482}
483int run_diff_index(struct rev_info *revs, int cached)
485{
486 struct object_array_entry *ent;
487 ent = revs->pending.objects;
489 if (diff_cache(revs, ent->item->sha1, ent->name, cached))
490 exit(128);
491 diff_set_mnemonic_prefix(&revs->diffopt, "c/", cached ? "i/" : "w/");
493 diffcore_fix_diff_index(&revs->diffopt);
494 diffcore_std(&revs->diffopt);
495 diff_flush(&revs->diffopt);
496 return 0;
497}
498int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
500{
501 struct rev_info revs;
502 init_revisions(&revs, NULL);
504 copy_pathspec(&revs.prune_data, &opt->pathspec);
505 revs.diffopt = *opt;
506 if (diff_cache(&revs, tree_sha1, NULL, 1))
508 exit(128);
509 return 0;
510}
511int index_differs_from(const char *def, int diff_flags)
513{
514 struct rev_info rev;
515 struct setup_revision_opt opt;
516 init_revisions(&rev, NULL);
518 memset(&opt, 0, sizeof(opt));
519 opt.def = def;
520 setup_revisions(0, NULL, &rev, &opt);
521 DIFF_OPT_SET(&rev.diffopt, QUICK);
522 DIFF_OPT_SET(&rev.diffopt, EXIT_WITH_STATUS);
523 rev.diffopt.flags |= diff_flags;
524 run_diff_index(&rev, 1);
525 if (rev.pending.alloc)
526 free(rev.pending.objects);
527 return (DIFF_OPT_TST(&rev.diffopt, HAS_CHANGES) != 0);
528}