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 dpath->len = path_len;
128 memcpy(dpath->path, ce->name, path_len);
129 dpath->path[path_len] = '\0';
130 hashclr(dpath->sha1);
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 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 diff_addremove(&revs->diffopt, '-', ce->ce_mode,
208 ce->sha1, !is_null_sha1(ce->sha1),
209 ce->name, 0);
210 continue;
211 }
212 changed = match_stat_with_submodule(&revs->diffopt, ce, &st,
213 ce_option, &dirty_submodule);
214 if (!changed && !dirty_submodule) {
215 ce_mark_uptodate(ce);
216 if (!DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
217 continue;
218 }
219 oldmode = ce->ce_mode;
220 newmode = ce_mode_from_stat(ce, st.st_mode);
221 diff_change(&revs->diffopt, oldmode, newmode,
222 ce->sha1, (changed ? null_sha1 : ce->sha1),
223 !is_null_sha1(ce->sha1), (changed ? 0 : !is_null_sha1(ce->sha1)),
224 ce->name, 0, dirty_submodule);
225 }
227 diffcore_std(&revs->diffopt);
228 diff_flush(&revs->diffopt);
229 return 0;
230}
231/*
233 * diff-index
234 */
235/* A file entry went away or appeared */
237static void diff_index_show_file(struct rev_info *revs,
238 const char *prefix,
239 const struct cache_entry *ce,
240 const unsigned char *sha1, int sha1_valid,
241 unsigned int mode,
242 unsigned dirty_submodule)
243{
244 diff_addremove(&revs->diffopt, prefix[0], mode,
245 sha1, sha1_valid, ce->name, dirty_submodule);
246}
247static int get_stat_data(const 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 const 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 tree.
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, !is_null_sha1(sha1), mode, dirty_submodule);
301}
302static int show_modified(struct rev_info *revs,
304 const struct cache_entry *old,
305 const 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, 1, 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, 1, !is_null_sha1(sha1),
353 old->name, 0, dirty_submodule);
354 return 0;
355}
356/*
358 * This gets a mix of an existing index and a tree, one pathname entry
359 * at a time. The index entry may be a single stage-0 one, but it could
360 * also be multiple unmerged entries (in which case idx_pos/idx_nr will
361 * give you the position and number of entries in the index).
362 */
363static void do_oneway_diff(struct unpack_trees_options *o,
364 const struct cache_entry *idx,
365 const struct cache_entry *tree)
366{
367 struct rev_info *revs = o->unpack_data;
368 int match_missing, cached;
369 /* if the entry is not checked out, don't examine work tree */
371 cached = o->index_only ||
372 (idx && ((idx->ce_flags & CE_VALID) || ce_skip_worktree(idx)));
373 /*
374 * Backward compatibility wart - "diff-index -m" does
375 * not mean "do not ignore merges", but "match_missing".
376 *
377 * But with the revision flag parsing, that's found in
378 * "!revs->ignore_merges".
379 */
380 match_missing = !revs->ignore_merges;
381 if (cached && idx && ce_stage(idx)) {
383 struct diff_filepair *pair;
384 pair = diff_unmerge(&revs->diffopt, idx->name);
385 if (tree)
386 fill_filespec(pair->one, tree->sha1, 1, tree->ce_mode);
387 return;
388 }
389 /*
391 * Something added to the tree?
392 */
393 if (!tree) {
394 show_new_file(revs, idx, cached, match_missing);
395 return;
396 }
397 /*
399 * Something removed from the tree?
400 */
401 if (!idx) {
402 diff_index_show_file(revs, "-", tree, tree->sha1, 1, tree->ce_mode, 0);
403 return;
404 }
405 /* Show difference between old and new */
407 show_modified(revs, tree, idx, 1, cached, match_missing);
408}
409/*
411 * The unpack_trees() interface is designed for merging, so
412 * the different source entries are designed primarily for
413 * the source trees, with the old index being really mainly
414 * used for being replaced by the result.
415 *
416 * For diffing, the index is more important, and we only have a
417 * single tree.
418 *
419 * We're supposed to advance o->pos to skip what we have already processed.
420 *
421 * This wrapper makes it all more readable, and takes care of all
422 * the fairly complex unpack_trees() semantic requirements, including
423 * the skipping, the path matching, the type conflict cases etc.
424 */
425static int oneway_diff(const struct cache_entry * const *src,
426 struct unpack_trees_options *o)
427{
428 const struct cache_entry *idx = src[0];
429 const struct cache_entry *tree = src[1];
430 struct rev_info *revs = o->unpack_data;
431 /*
433 * Unpack-trees generates a DF/conflict entry if
434 * there was a directory in the index and a tree
435 * in the tree. From a diff standpoint, that's a
436 * delete of the tree and a create of the file.
437 */
438 if (tree == o->df_conflict_entry)
439 tree = NULL;
440 if (ce_path_match(idx ? idx : tree, &revs->prune_data)) {
442 do_oneway_diff(o, idx, tree);
443 if (diff_can_quit_early(&revs->diffopt)) {
444 o->exiting_early = 1;
445 return -1;
446 }
447 }
448 return 0;
450}
451static int diff_cache(struct rev_info *revs,
453 const unsigned char *tree_sha1,
454 const char *tree_name,
455 int cached)
456{
457 struct tree *tree;
458 struct tree_desc t;
459 struct unpack_trees_options opts;
460 tree = parse_tree_indirect(tree_sha1);
462 if (!tree)
463 return error("bad tree object %s",
464 tree_name ? tree_name : sha1_to_hex(tree_sha1));
465 memset(&opts, 0, sizeof(opts));
466 opts.head_idx = 1;
467 opts.index_only = cached;
468 opts.diff_index_cached = (cached &&
469 !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER));
470 opts.merge = 1;
471 opts.fn = oneway_diff;
472 opts.unpack_data = revs;
473 opts.src_index = &the_index;
474 opts.dst_index = NULL;
475 opts.pathspec = &revs->diffopt.pathspec;
476 opts.pathspec->recursive = 1;
477 init_tree_desc(&t, tree->buffer, tree->size);
479 return unpack_trees(1, &t, &opts);
480}
481int run_diff_index(struct rev_info *revs, int cached)
483{
484 struct object_array_entry *ent;
485 ent = revs->pending.objects;
487 if (diff_cache(revs, ent->item->sha1, ent->name, cached))
488 exit(128);
489 diff_set_mnemonic_prefix(&revs->diffopt, "c/", cached ? "i/" : "w/");
491 diffcore_fix_diff_index(&revs->diffopt);
492 diffcore_std(&revs->diffopt);
493 diff_flush(&revs->diffopt);
494 return 0;
495}
496int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
498{
499 struct rev_info revs;
500 init_revisions(&revs, NULL);
502 copy_pathspec(&revs.prune_data, &opt->pathspec);
503 revs.diffopt = *opt;
504 if (diff_cache(&revs, tree_sha1, NULL, 1))
506 exit(128);
507 return 0;
508}
509int index_differs_from(const char *def, int diff_flags)
511{
512 struct rev_info rev;
513 struct setup_revision_opt opt;
514 init_revisions(&rev, NULL);
516 memset(&opt, 0, sizeof(opt));
517 opt.def = def;
518 setup_revisions(0, NULL, &rev, &opt);
519 DIFF_OPT_SET(&rev.diffopt, QUICK);
520 DIFF_OPT_SET(&rev.diffopt, EXIT_WITH_STATUS);
521 rev.diffopt.flags |= diff_flags;
522 run_diff_index(&rev, 1);
523 if (rev.pending.alloc)
524 free(rev.pending.objects);
525 return (DIFF_OPT_TST(&rev.diffopt, HAS_CHANGES) != 0);
526}