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 unsigned ce_option = ((option & DIFF_RACY_IS_MODIFIED)
91 ? CE_MATCH_RACY_IS_DIRTY : 0);
92 if (option & DIFF_SILENT_ON_REMOVED)
94 handle_deprecated_show_diff_q(&revs->diffopt);
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 struct stat st;
103 unsigned int oldmode, newmode;
104 struct cache_entry *ce = active_cache[i];
105 int changed;
106 unsigned dirty_submodule = 0;
107 if (diff_can_quit_early(&revs->diffopt))
109 break;
110 if (!ce_path_match(ce, &revs->prune_data))
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 path_len = ce_namelen(ce);
122 dpath = xmalloc(combine_diff_path_size(5, path_len));
124 dpath->path = (char *) &(dpath->parent[5]);
125 dpath->next = NULL;
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 wt_mode = 0;
142 }
143 dpath->mode = wt_mode;
144 while (i < entries) {
146 struct cache_entry *nce = active_cache[i];
147 int stage;
148 if (strcmp(ce->name, nce->name))
150 break;
151 /* Stage #2 (ours) is the first parent,
153 * stage #3 (theirs) is the second.
154 */
155 stage = ce_stage(nce);
156 if (2 <= stage) {
157 int mode = nce->ce_mode;
158 num_compare_stages++;
159 hashcpy(dpath->parent[stage-2].sha1, nce->sha1);
160 dpath->parent[stage-2].mode = ce_mode_from_stat(nce, mode);
161 dpath->parent[stage-2].status =
162 DIFF_STATUS_MODIFIED;
163 }
164 /* diff against the proper unmerged stage */
166 if (stage == diff_unmerged_stage)
167 ce = nce;
168 i++;
169 }
170 /*
171 * Compensate for loop update
172 */
173 i--;
174 if (revs->combine_merges && num_compare_stages == 2) {
176 show_combined_diff(dpath, 2,
177 revs->dense_combined_merges,
178 revs);
179 free(dpath);
180 continue;
181 }
182 free(dpath);
183 dpath = NULL;
184 /*
186 * Show the diff for the 'ce' if we found the one
187 * from the desired stage.
188 */
189 pair = diff_unmerge(&revs->diffopt, ce->name);
190 if (wt_mode)
191 pair->two->mode = wt_mode;
192 if (ce_stage(ce) != diff_unmerged_stage)
193 continue;
194 }
195 if (ce_uptodate(ce) || ce_skip_worktree(ce))
197 continue;
198 /* If CE_VALID is set, don't look at workdir for file removal */
200 changed = (ce->ce_flags & CE_VALID) ? 0 : check_removed(ce, &st);
201 if (changed) {
202 if (changed < 0) {
203 perror(ce->name);
204 continue;
205 }
206 diff_addremove(&revs->diffopt, '-', ce->ce_mode,
207 ce->sha1, !is_null_sha1(ce->sha1),
208 ce->name, 0);
209 continue;
210 }
211 changed = match_stat_with_submodule(&revs->diffopt, ce, &st,
212 ce_option, &dirty_submodule);
213 if (!changed && !dirty_submodule) {
214 ce_mark_uptodate(ce);
215 if (!DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
216 continue;
217 }
218 oldmode = ce->ce_mode;
219 newmode = ce_mode_from_stat(ce, st.st_mode);
220 diff_change(&revs->diffopt, oldmode, newmode,
221 ce->sha1, (changed ? null_sha1 : ce->sha1),
222 !is_null_sha1(ce->sha1), (changed ? 0 : !is_null_sha1(ce->sha1)),
223 ce->name, 0, dirty_submodule);
224 }
226 diffcore_std(&revs->diffopt);
227 diff_flush(&revs->diffopt);
228 return 0;
229}
230/*
232 * diff-index
233 */
234/* A file entry went away or appeared */
236static void diff_index_show_file(struct rev_info *revs,
237 const char *prefix,
238 const struct cache_entry *ce,
239 const unsigned char *sha1, int sha1_valid,
240 unsigned int mode,
241 unsigned dirty_submodule)
242{
243 diff_addremove(&revs->diffopt, prefix[0], mode,
244 sha1, sha1_valid, ce->name, dirty_submodule);
245}
246static int get_stat_data(const struct cache_entry *ce,
248 const unsigned char **sha1p,
249 unsigned int *modep,
250 int cached, int match_missing,
251 unsigned *dirty_submodule, struct diff_options *diffopt)
252{
253 const unsigned char *sha1 = ce->sha1;
254 unsigned int mode = ce->ce_mode;
255 if (!cached && !ce_uptodate(ce)) {
257 int changed;
258 struct stat st;
259 changed = check_removed(ce, &st);
260 if (changed < 0)
261 return -1;
262 else if (changed) {
263 if (match_missing) {
264 *sha1p = sha1;
265 *modep = mode;
266 return 0;
267 }
268 return -1;
269 }
270 changed = match_stat_with_submodule(diffopt, ce, &st,
271 0, dirty_submodule);
272 if (changed) {
273 mode = ce_mode_from_stat(ce, st.st_mode);
274 sha1 = null_sha1;
275 }
276 }
277 *sha1p = sha1;
279 *modep = mode;
280 return 0;
281}
282static void show_new_file(struct rev_info *revs,
284 const struct cache_entry *new,
285 int cached, int match_missing)
286{
287 const unsigned char *sha1;
288 unsigned int mode;
289 unsigned dirty_submodule = 0;
290 /*
292 * New file in the index: it might actually be different in
293 * the working tree.
294 */
295 if (get_stat_data(new, &sha1, &mode, cached, match_missing,
296 &dirty_submodule, &revs->diffopt) < 0)
297 return;
298 diff_index_show_file(revs, "+", new, sha1, !is_null_sha1(sha1), mode, dirty_submodule);
300}
301static int show_modified(struct rev_info *revs,
303 const struct cache_entry *old,
304 const struct cache_entry *new,
305 int report_missing,
306 int cached, int match_missing)
307{
308 unsigned int mode, oldmode;
309 const unsigned char *sha1;
310 unsigned dirty_submodule = 0;
311 if (get_stat_data(new, &sha1, &mode, cached, match_missing,
313 &dirty_submodule, &revs->diffopt) < 0) {
314 if (report_missing)
315 diff_index_show_file(revs, "-", old,
316 old->sha1, 1, old->ce_mode, 0);
317 return -1;
318 }
319 if (revs->combine_merges && !cached &&
321 (hashcmp(sha1, old->sha1) || hashcmp(old->sha1, new->sha1))) {
322 struct combine_diff_path *p;
323 int pathlen = ce_namelen(new);
324 p = xmalloc(combine_diff_path_size(2, pathlen));
326 p->path = (char *) &p->parent[2];
327 p->next = NULL;
328 memcpy(p->path, new->name, pathlen);
329 p->path[pathlen] = 0;
330 p->mode = mode;
331 hashclr(p->sha1);
332 memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
333 p->parent[0].status = DIFF_STATUS_MODIFIED;
334 p->parent[0].mode = new->ce_mode;
335 hashcpy(p->parent[0].sha1, new->sha1);
336 p->parent[1].status = DIFF_STATUS_MODIFIED;
337 p->parent[1].mode = old->ce_mode;
338 hashcpy(p->parent[1].sha1, old->sha1);
339 show_combined_diff(p, 2, revs->dense_combined_merges, revs);
340 free(p);
341 return 0;
342 }
343 oldmode = old->ce_mode;
345 if (mode == oldmode && !hashcmp(sha1, old->sha1) && !dirty_submodule &&
346 !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
347 return 0;
348 diff_change(&revs->diffopt, oldmode, mode,
350 old->sha1, sha1, 1, !is_null_sha1(sha1),
351 old->name, 0, dirty_submodule);
352 return 0;
353}
354/*
356 * This gets a mix of an existing index and a tree, one pathname entry
357 * at a time. The index entry may be a single stage-0 one, but it could
358 * also be multiple unmerged entries (in which case idx_pos/idx_nr will
359 * give you the position and number of entries in the index).
360 */
361static void do_oneway_diff(struct unpack_trees_options *o,
362 const struct cache_entry *idx,
363 const struct cache_entry *tree)
364{
365 struct rev_info *revs = o->unpack_data;
366 int match_missing, cached;
367 /* if the entry is not checked out, don't examine work tree */
369 cached = o->index_only ||
370 (idx && ((idx->ce_flags & CE_VALID) || ce_skip_worktree(idx)));
371 /*
372 * Backward compatibility wart - "diff-index -m" does
373 * not mean "do not ignore merges", but "match_missing".
374 *
375 * But with the revision flag parsing, that's found in
376 * "!revs->ignore_merges".
377 */
378 match_missing = !revs->ignore_merges;
379 if (cached && idx && ce_stage(idx)) {
381 struct diff_filepair *pair;
382 pair = diff_unmerge(&revs->diffopt, idx->name);
383 if (tree)
384 fill_filespec(pair->one, tree->sha1, 1, tree->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, 1, 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(const struct cache_entry * const *src,
424 struct unpack_trees_options *o)
425{
426 const struct cache_entry *idx = src[0];
427 const struct cache_entry *tree = src[1];
428 struct rev_info *revs = o->unpack_data;
429 /*
431 * Unpack-trees generates a DF/conflict entry if
432 * there was a directory in the index and a tree
433 * in the tree. From a diff standpoint, that's a
434 * delete of the tree and a create of the file.
435 */
436 if (tree == o->df_conflict_entry)
437 tree = NULL;
438 if (ce_path_match(idx ? idx : tree, &revs->prune_data)) {
440 do_oneway_diff(o, idx, tree);
441 if (diff_can_quit_early(&revs->diffopt)) {
442 o->exiting_early = 1;
443 return -1;
444 }
445 }
446 return 0;
448}
449static int diff_cache(struct rev_info *revs,
451 const unsigned char *tree_sha1,
452 const char *tree_name,
453 int cached)
454{
455 struct tree *tree;
456 struct tree_desc t;
457 struct unpack_trees_options opts;
458 tree = parse_tree_indirect(tree_sha1);
460 if (!tree)
461 return error("bad tree object %s",
462 tree_name ? tree_name : sha1_to_hex(tree_sha1));
463 memset(&opts, 0, sizeof(opts));
464 opts.head_idx = 1;
465 opts.index_only = cached;
466 opts.diff_index_cached = (cached &&
467 !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER));
468 opts.merge = 1;
469 opts.fn = oneway_diff;
470 opts.unpack_data = revs;
471 opts.src_index = &the_index;
472 opts.dst_index = NULL;
473 opts.pathspec = &revs->diffopt.pathspec;
474 opts.pathspec->recursive = 1;
475 init_tree_desc(&t, tree->buffer, tree->size);
477 return unpack_trees(1, &t, &opts);
478}
479int run_diff_index(struct rev_info *revs, int cached)
481{
482 struct object_array_entry *ent;
483 ent = revs->pending.objects;
485 if (diff_cache(revs, ent->item->sha1, ent->name, cached))
486 exit(128);
487 diff_set_mnemonic_prefix(&revs->diffopt, "c/", cached ? "i/" : "w/");
489 diffcore_fix_diff_index(&revs->diffopt);
490 diffcore_std(&revs->diffopt);
491 diff_flush(&revs->diffopt);
492 return 0;
493}
494int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
496{
497 struct rev_info revs;
498 init_revisions(&revs, NULL);
500 copy_pathspec(&revs.prune_data, &opt->pathspec);
501 revs.diffopt = *opt;
502 if (diff_cache(&revs, tree_sha1, NULL, 1))
504 exit(128);
505 return 0;
506}
507int index_differs_from(const char *def, int diff_flags)
509{
510 struct rev_info rev;
511 struct setup_revision_opt opt;
512 init_revisions(&rev, NULL);
514 memset(&opt, 0, sizeof(opt));
515 opt.def = def;
516 setup_revisions(0, NULL, &rev, &opt);
517 DIFF_OPT_SET(&rev.diffopt, QUICK);
518 DIFF_OPT_SET(&rev.diffopt, EXIT_WITH_STATUS);
519 rev.diffopt.flags |= diff_flags;
520 run_diff_index(&rev, 1);
521 if (rev.pending.alloc)
522 free(rev.pending.objects);
523 return (DIFF_OPT_TST(&rev.diffopt, HAS_CHANGES) != 0);
524}