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 if (diff_can_quit_early(&revs->diffopt))
106 break;
107 if (!ce_path_match(ce, &revs->prune_data, NULL))
109 continue;
110 if (ce_stage(ce)) {
112 struct combine_diff_path *dpath;
113 struct diff_filepair *pair;
114 unsigned int wt_mode = 0;
115 int num_compare_stages = 0;
116 size_t path_len;
117 struct stat st;
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 memcpy(dpath->path, ce->name, path_len);
126 dpath->path[path_len] = '\0';
127 hashclr(dpath->sha1);
128 memset(&(dpath->parent[0]), 0,
129 sizeof(struct combine_diff_parent)*5);
130 changed = check_removed(ce, &st);
132 if (!changed)
133 wt_mode = ce_mode_from_stat(ce, st.st_mode);
134 else {
135 if (changed < 0) {
136 perror(ce->name);
137 continue;
138 }
139 wt_mode = 0;
140 }
141 dpath->mode = wt_mode;
142 while (i < entries) {
144 struct cache_entry *nce = active_cache[i];
145 int stage;
146 if (strcmp(ce->name, nce->name))
148 break;
149 /* Stage #2 (ours) is the first parent,
151 * stage #3 (theirs) is the second.
152 */
153 stage = ce_stage(nce);
154 if (2 <= stage) {
155 int mode = nce->ce_mode;
156 num_compare_stages++;
157 hashcpy(dpath->parent[stage-2].sha1, nce->sha1);
158 dpath->parent[stage-2].mode = ce_mode_from_stat(nce, mode);
159 dpath->parent[stage-2].status =
160 DIFF_STATUS_MODIFIED;
161 }
162 /* diff against the proper unmerged stage */
164 if (stage == diff_unmerged_stage)
165 ce = nce;
166 i++;
167 }
168 /*
169 * Compensate for loop update
170 */
171 i--;
172 if (revs->combine_merges && num_compare_stages == 2) {
174 show_combined_diff(dpath, 2,
175 revs->dense_combined_merges,
176 revs);
177 free(dpath);
178 continue;
179 }
180 free(dpath);
181 dpath = NULL;
182 /*
184 * Show the diff for the 'ce' if we found the one
185 * from the desired stage.
186 */
187 pair = diff_unmerge(&revs->diffopt, ce->name);
188 if (wt_mode)
189 pair->two->mode = wt_mode;
190 if (ce_stage(ce) != diff_unmerged_stage)
191 continue;
192 }
193 if (ce_uptodate(ce) || ce_skip_worktree(ce))
195 continue;
196 /* If CE_VALID is set, don't look at workdir for file removal */
198 if (ce->ce_flags & CE_VALID) {
199 changed = 0;
200 newmode = ce->ce_mode;
201 } else {
202 struct stat st;
203 changed = check_removed(ce, &st);
205 if (changed) {
206 if (changed < 0) {
207 perror(ce->name);
208 continue;
209 }
210 diff_addremove(&revs->diffopt, '-', ce->ce_mode,
211 ce->sha1, !is_null_sha1(ce->sha1),
212 ce->name, 0);
213 continue;
214 }
215 changed = match_stat_with_submodule(&revs->diffopt, ce, &st,
217 ce_option, &dirty_submodule);
218 newmode = ce_mode_from_stat(ce, st.st_mode);
219 }
220 if (!changed && !dirty_submodule) {
222 ce_mark_uptodate(ce);
223 if (!DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
224 continue;
225 }
226 oldmode = ce->ce_mode;
227 diff_change(&revs->diffopt, oldmode, newmode,
228 ce->sha1, (changed ? null_sha1 : ce->sha1),
229 !is_null_sha1(ce->sha1), (changed ? 0 : !is_null_sha1(ce->sha1)),
230 ce->name, 0, dirty_submodule);
231 }
233 diffcore_std(&revs->diffopt);
234 diff_flush(&revs->diffopt);
235 return 0;
236}
237/*
239 * diff-index
240 */
241/* A file entry went away or appeared */
243static void diff_index_show_file(struct rev_info *revs,
244 const char *prefix,
245 const struct cache_entry *ce,
246 const unsigned char *sha1, int sha1_valid,
247 unsigned int mode,
248 unsigned dirty_submodule)
249{
250 diff_addremove(&revs->diffopt, prefix[0], mode,
251 sha1, sha1_valid, ce->name, dirty_submodule);
252}
253static int get_stat_data(const struct cache_entry *ce,
255 const unsigned char **sha1p,
256 unsigned int *modep,
257 int cached, int match_missing,
258 unsigned *dirty_submodule, struct diff_options *diffopt)
259{
260 const unsigned char *sha1 = ce->sha1;
261 unsigned int mode = ce->ce_mode;
262 if (!cached && !ce_uptodate(ce)) {
264 int changed;
265 struct stat st;
266 changed = check_removed(ce, &st);
267 if (changed < 0)
268 return -1;
269 else if (changed) {
270 if (match_missing) {
271 *sha1p = sha1;
272 *modep = mode;
273 return 0;
274 }
275 return -1;
276 }
277 changed = match_stat_with_submodule(diffopt, ce, &st,
278 0, dirty_submodule);
279 if (changed) {
280 mode = ce_mode_from_stat(ce, st.st_mode);
281 sha1 = null_sha1;
282 }
283 }
284 *sha1p = sha1;
286 *modep = mode;
287 return 0;
288}
289static void show_new_file(struct rev_info *revs,
291 const struct cache_entry *new,
292 int cached, int match_missing)
293{
294 const unsigned char *sha1;
295 unsigned int mode;
296 unsigned dirty_submodule = 0;
297 /*
299 * New file in the index: it might actually be different in
300 * the working tree.
301 */
302 if (get_stat_data(new, &sha1, &mode, cached, match_missing,
303 &dirty_submodule, &revs->diffopt) < 0)
304 return;
305 diff_index_show_file(revs, "+", new, sha1, !is_null_sha1(sha1), mode, dirty_submodule);
307}
308static int show_modified(struct rev_info *revs,
310 const struct cache_entry *old,
311 const struct cache_entry *new,
312 int report_missing,
313 int cached, int match_missing)
314{
315 unsigned int mode, oldmode;
316 const unsigned char *sha1;
317 unsigned dirty_submodule = 0;
318 if (get_stat_data(new, &sha1, &mode, cached, match_missing,
320 &dirty_submodule, &revs->diffopt) < 0) {
321 if (report_missing)
322 diff_index_show_file(revs, "-", old,
323 old->sha1, 1, old->ce_mode, 0);
324 return -1;
325 }
326 if (revs->combine_merges && !cached &&
328 (hashcmp(sha1, old->sha1) || hashcmp(old->sha1, new->sha1))) {
329 struct combine_diff_path *p;
330 int pathlen = ce_namelen(new);
331 p = xmalloc(combine_diff_path_size(2, pathlen));
333 p->path = (char *) &p->parent[2];
334 p->next = NULL;
335 memcpy(p->path, new->name, pathlen);
336 p->path[pathlen] = 0;
337 p->mode = mode;
338 hashclr(p->sha1);
339 memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
340 p->parent[0].status = DIFF_STATUS_MODIFIED;
341 p->parent[0].mode = new->ce_mode;
342 hashcpy(p->parent[0].sha1, new->sha1);
343 p->parent[1].status = DIFF_STATUS_MODIFIED;
344 p->parent[1].mode = old->ce_mode;
345 hashcpy(p->parent[1].sha1, old->sha1);
346 show_combined_diff(p, 2, revs->dense_combined_merges, revs);
347 free(p);
348 return 0;
349 }
350 oldmode = old->ce_mode;
352 if (mode == oldmode && !hashcmp(sha1, old->sha1) && !dirty_submodule &&
353 !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
354 return 0;
355 diff_change(&revs->diffopt, oldmode, mode,
357 old->sha1, sha1, 1, !is_null_sha1(sha1),
358 old->name, 0, dirty_submodule);
359 return 0;
360}
361/*
363 * This gets a mix of an existing index and a tree, one pathname entry
364 * at a time. The index entry may be a single stage-0 one, but it could
365 * also be multiple unmerged entries (in which case idx_pos/idx_nr will
366 * give you the position and number of entries in the index).
367 */
368static void do_oneway_diff(struct unpack_trees_options *o,
369 const struct cache_entry *idx,
370 const struct cache_entry *tree)
371{
372 struct rev_info *revs = o->unpack_data;
373 int match_missing, cached;
374 /* if the entry is not checked out, don't examine work tree */
376 cached = o->index_only ||
377 (idx && ((idx->ce_flags & CE_VALID) || ce_skip_worktree(idx)));
378 /*
379 * Backward compatibility wart - "diff-index -m" does
380 * not mean "do not ignore merges", but "match_missing".
381 *
382 * But with the revision flag parsing, that's found in
383 * "!revs->ignore_merges".
384 */
385 match_missing = !revs->ignore_merges;
386 if (cached && idx && ce_stage(idx)) {
388 struct diff_filepair *pair;
389 pair = diff_unmerge(&revs->diffopt, idx->name);
390 if (tree)
391 fill_filespec(pair->one, tree->sha1, 1, tree->ce_mode);
392 return;
393 }
394 /*
396 * Something added to the tree?
397 */
398 if (!tree) {
399 show_new_file(revs, idx, cached, match_missing);
400 return;
401 }
402 /*
404 * Something removed from the tree?
405 */
406 if (!idx) {
407 diff_index_show_file(revs, "-", tree, tree->sha1, 1, tree->ce_mode, 0);
408 return;
409 }
410 /* Show difference between old and new */
412 show_modified(revs, tree, idx, 1, cached, match_missing);
413}
414/*
416 * The unpack_trees() interface is designed for merging, so
417 * the different source entries are designed primarily for
418 * the source trees, with the old index being really mainly
419 * used for being replaced by the result.
420 *
421 * For diffing, the index is more important, and we only have a
422 * single tree.
423 *
424 * We're supposed to advance o->pos to skip what we have already processed.
425 *
426 * This wrapper makes it all more readable, and takes care of all
427 * the fairly complex unpack_trees() semantic requirements, including
428 * the skipping, the path matching, the type conflict cases etc.
429 */
430static int oneway_diff(const struct cache_entry * const *src,
431 struct unpack_trees_options *o)
432{
433 const struct cache_entry *idx = src[0];
434 const struct cache_entry *tree = src[1];
435 struct rev_info *revs = o->unpack_data;
436 /*
438 * Unpack-trees generates a DF/conflict entry if
439 * there was a directory in the index and a tree
440 * in the tree. From a diff standpoint, that's a
441 * delete of the tree and a create of the file.
442 */
443 if (tree == o->df_conflict_entry)
444 tree = NULL;
445 if (ce_path_match(idx ? idx : tree, &revs->prune_data, NULL)) {
447 do_oneway_diff(o, idx, tree);
448 if (diff_can_quit_early(&revs->diffopt)) {
449 o->exiting_early = 1;
450 return -1;
451 }
452 }
453 return 0;
455}
456static int diff_cache(struct rev_info *revs,
458 const unsigned char *tree_sha1,
459 const char *tree_name,
460 int cached)
461{
462 struct tree *tree;
463 struct tree_desc t;
464 struct unpack_trees_options opts;
465 tree = parse_tree_indirect(tree_sha1);
467 if (!tree)
468 return error("bad tree object %s",
469 tree_name ? tree_name : sha1_to_hex(tree_sha1));
470 memset(&opts, 0, sizeof(opts));
471 opts.head_idx = 1;
472 opts.index_only = cached;
473 opts.diff_index_cached = (cached &&
474 !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER));
475 opts.merge = 1;
476 opts.fn = oneway_diff;
477 opts.unpack_data = revs;
478 opts.src_index = &the_index;
479 opts.dst_index = NULL;
480 opts.pathspec = &revs->diffopt.pathspec;
481 opts.pathspec->recursive = 1;
482 init_tree_desc(&t, tree->buffer, tree->size);
484 return unpack_trees(1, &t, &opts);
485}
486int run_diff_index(struct rev_info *revs, int cached)
488{
489 struct object_array_entry *ent;
490 ent = revs->pending.objects;
492 if (diff_cache(revs, ent->item->sha1, ent->name, cached))
493 exit(128);
494 diff_set_mnemonic_prefix(&revs->diffopt, "c/", cached ? "i/" : "w/");
496 diffcore_fix_diff_index(&revs->diffopt);
497 diffcore_std(&revs->diffopt);
498 diff_flush(&revs->diffopt);
499 return 0;
500}
501int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
503{
504 struct rev_info revs;
505 init_revisions(&revs, NULL);
507 copy_pathspec(&revs.prune_data, &opt->pathspec);
508 revs.diffopt = *opt;
509 if (diff_cache(&revs, tree_sha1, NULL, 1))
511 exit(128);
512 return 0;
513}
514int index_differs_from(const char *def, int diff_flags)
516{
517 struct rev_info rev;
518 struct setup_revision_opt opt;
519 init_revisions(&rev, NULL);
521 memset(&opt, 0, sizeof(opt));
522 opt.def = def;
523 setup_revisions(0, NULL, &rev, &opt);
524 DIFF_OPT_SET(&rev.diffopt, QUICK);
525 DIFF_OPT_SET(&rev.diffopt, EXIT_WITH_STATUS);
526 rev.diffopt.flags |= diff_flags;
527 run_diff_index(&rev, 1);
528 if (rev.pending.alloc)
529 free(rev.pending.objects);
530 return (DIFF_OPT_TST(&rev.diffopt, HAS_CHANGES) != 0);
531}