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 unsigned ce_option = ((option & DIFF_RACY_IS_MODIFIED)
90 ? CE_MATCH_RACY_IS_DIRTY : 0);
91 diff_set_mnemonic_prefix(&revs->diffopt, "i/", "w/");
93 if (diff_unmerged_stage < 0)
95 diff_unmerged_stage = 2;
96 entries = active_nr;
97 for (i = 0; i < entries; i++) {
98 struct stat st;
99 unsigned int oldmode, newmode;
100 struct cache_entry *ce = active_cache[i];
101 int changed;
102 unsigned dirty_submodule = 0;
103 if (diff_can_quit_early(&revs->diffopt))
105 break;
106 if (!ce_path_match(ce, &revs->prune_data))
108 continue;
109 if (ce_stage(ce)) {
111 struct combine_diff_path *dpath;
112 struct diff_filepair *pair;
113 unsigned int wt_mode = 0;
114 int num_compare_stages = 0;
115 size_t path_len;
116 path_len = ce_namelen(ce);
118 dpath = xmalloc(combine_diff_path_size(5, path_len));
120 dpath->path = (char *) &(dpath->parent[5]);
121 dpath->next = NULL;
123 dpath->len = path_len;
124 memcpy(dpath->path, ce->name, path_len);
125 dpath->path[path_len] = '\0';
126 hashclr(dpath->sha1);
127 memset(&(dpath->parent[0]), 0,
128 sizeof(struct combine_diff_parent)*5);
129 changed = check_removed(ce, &st);
131 if (!changed)
132 wt_mode = ce_mode_from_stat(ce, st.st_mode);
133 else {
134 if (changed < 0) {
135 perror(ce->name);
136 continue;
137 }
138 wt_mode = 0;
139 }
140 dpath->mode = wt_mode;
141 while (i < entries) {
143 struct cache_entry *nce = active_cache[i];
144 int stage;
145 if (strcmp(ce->name, nce->name))
147 break;
148 /* Stage #2 (ours) is the first parent,
150 * stage #3 (theirs) is the second.
151 */
152 stage = ce_stage(nce);
153 if (2 <= stage) {
154 int mode = nce->ce_mode;
155 num_compare_stages++;
156 hashcpy(dpath->parent[stage-2].sha1, nce->sha1);
157 dpath->parent[stage-2].mode = ce_mode_from_stat(nce, mode);
158 dpath->parent[stage-2].status =
159 DIFF_STATUS_MODIFIED;
160 }
161 /* diff against the proper unmerged stage */
163 if (stage == diff_unmerged_stage)
164 ce = nce;
165 i++;
166 }
167 /*
168 * Compensate for loop update
169 */
170 i--;
171 if (revs->combine_merges && num_compare_stages == 2) {
173 show_combined_diff(dpath, 2,
174 revs->dense_combined_merges,
175 revs);
176 free(dpath);
177 continue;
178 }
179 free(dpath);
180 dpath = NULL;
181 /*
183 * Show the diff for the 'ce' if we found the one
184 * from the desired stage.
185 */
186 pair = diff_unmerge(&revs->diffopt, ce->name);
187 if (wt_mode)
188 pair->two->mode = wt_mode;
189 if (ce_stage(ce) != diff_unmerged_stage)
190 continue;
191 }
192 if (ce_uptodate(ce) || ce_skip_worktree(ce))
194 continue;
195 /* If CE_VALID is set, don't look at workdir for file removal */
197 changed = (ce->ce_flags & CE_VALID) ? 0 : check_removed(ce, &st);
198 if (changed) {
199 if (changed < 0) {
200 perror(ce->name);
201 continue;
202 }
203 diff_addremove(&revs->diffopt, '-', ce->ce_mode,
204 ce->sha1, !is_null_sha1(ce->sha1),
205 ce->name, 0);
206 continue;
207 }
208 changed = match_stat_with_submodule(&revs->diffopt, ce, &st,
209 ce_option, &dirty_submodule);
210 if (!changed && !dirty_submodule) {
211 ce_mark_uptodate(ce);
212 if (!DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
213 continue;
214 }
215 oldmode = ce->ce_mode;
216 newmode = ce_mode_from_stat(ce, st.st_mode);
217 diff_change(&revs->diffopt, oldmode, newmode,
218 ce->sha1, (changed ? null_sha1 : ce->sha1),
219 !is_null_sha1(ce->sha1), (changed ? 0 : !is_null_sha1(ce->sha1)),
220 ce->name, 0, dirty_submodule);
221 }
223 diffcore_std(&revs->diffopt);
224 diff_flush(&revs->diffopt);
225 return 0;
226}
227/*
229 * diff-index
230 */
231/* A file entry went away or appeared */
233static void diff_index_show_file(struct rev_info *revs,
234 const char *prefix,
235 struct cache_entry *ce,
236 const unsigned char *sha1, int sha1_valid,
237 unsigned int mode,
238 unsigned dirty_submodule)
239{
240 diff_addremove(&revs->diffopt, prefix[0], mode,
241 sha1, sha1_valid, ce->name, dirty_submodule);
242}
243static int get_stat_data(struct cache_entry *ce,
245 const unsigned char **sha1p,
246 unsigned int *modep,
247 int cached, int match_missing,
248 unsigned *dirty_submodule, struct diff_options *diffopt)
249{
250 const unsigned char *sha1 = ce->sha1;
251 unsigned int mode = ce->ce_mode;
252 if (!cached && !ce_uptodate(ce)) {
254 int changed;
255 struct stat st;
256 changed = check_removed(ce, &st);
257 if (changed < 0)
258 return -1;
259 else if (changed) {
260 if (match_missing) {
261 *sha1p = sha1;
262 *modep = mode;
263 return 0;
264 }
265 return -1;
266 }
267 changed = match_stat_with_submodule(diffopt, ce, &st,
268 0, dirty_submodule);
269 if (changed) {
270 mode = ce_mode_from_stat(ce, st.st_mode);
271 sha1 = null_sha1;
272 }
273 }
274 *sha1p = sha1;
276 *modep = mode;
277 return 0;
278}
279static void show_new_file(struct rev_info *revs,
281 struct cache_entry *new,
282 int cached, int match_missing)
283{
284 const unsigned char *sha1;
285 unsigned int mode;
286 unsigned dirty_submodule = 0;
287 /*
289 * New file in the index: it might actually be different in
290 * the working tree.
291 */
292 if (get_stat_data(new, &sha1, &mode, cached, match_missing,
293 &dirty_submodule, &revs->diffopt) < 0)
294 return;
295 diff_index_show_file(revs, "+", new, sha1, !is_null_sha1(sha1), mode, dirty_submodule);
297}
298static int show_modified(struct rev_info *revs,
300 struct cache_entry *old,
301 struct cache_entry *new,
302 int report_missing,
303 int cached, int match_missing)
304{
305 unsigned int mode, oldmode;
306 const unsigned char *sha1;
307 unsigned dirty_submodule = 0;
308 if (get_stat_data(new, &sha1, &mode, cached, match_missing,
310 &dirty_submodule, &revs->diffopt) < 0) {
311 if (report_missing)
312 diff_index_show_file(revs, "-", old,
313 old->sha1, 1, old->ce_mode, 0);
314 return -1;
315 }
316 if (revs->combine_merges && !cached &&
318 (hashcmp(sha1, old->sha1) || hashcmp(old->sha1, new->sha1))) {
319 struct combine_diff_path *p;
320 int pathlen = ce_namelen(new);
321 p = xmalloc(combine_diff_path_size(2, pathlen));
323 p->path = (char *) &p->parent[2];
324 p->next = NULL;
325 p->len = pathlen;
326 memcpy(p->path, new->name, pathlen);
327 p->path[pathlen] = 0;
328 p->mode = mode;
329 hashclr(p->sha1);
330 memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
331 p->parent[0].status = DIFF_STATUS_MODIFIED;
332 p->parent[0].mode = new->ce_mode;
333 hashcpy(p->parent[0].sha1, new->sha1);
334 p->parent[1].status = DIFF_STATUS_MODIFIED;
335 p->parent[1].mode = old->ce_mode;
336 hashcpy(p->parent[1].sha1, old->sha1);
337 show_combined_diff(p, 2, revs->dense_combined_merges, revs);
338 free(p);
339 return 0;
340 }
341 oldmode = old->ce_mode;
343 if (mode == oldmode && !hashcmp(sha1, old->sha1) && !dirty_submodule &&
344 !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
345 return 0;
346 diff_change(&revs->diffopt, oldmode, mode,
348 old->sha1, sha1, 1, !is_null_sha1(sha1),
349 old->name, 0, dirty_submodule);
350 return 0;
351}
352/*
354 * This gets a mix of an existing index and a tree, one pathname entry
355 * at a time. The index entry may be a single stage-0 one, but it could
356 * also be multiple unmerged entries (in which case idx_pos/idx_nr will
357 * give you the position and number of entries in the index).
358 */
359static void do_oneway_diff(struct unpack_trees_options *o,
360 struct cache_entry *idx,
361 struct cache_entry *tree)
362{
363 struct rev_info *revs = o->unpack_data;
364 int match_missing, cached;
365 /* if the entry is not checked out, don't examine work tree */
367 cached = o->index_only ||
368 (idx && ((idx->ce_flags & CE_VALID) || ce_skip_worktree(idx)));
369 /*
370 * Backward compatibility wart - "diff-index -m" does
371 * not mean "do not ignore merges", but "match_missing".
372 *
373 * But with the revision flag parsing, that's found in
374 * "!revs->ignore_merges".
375 */
376 match_missing = !revs->ignore_merges;
377 if (cached && idx && ce_stage(idx)) {
379 struct diff_filepair *pair;
380 pair = diff_unmerge(&revs->diffopt, idx->name);
381 if (tree)
382 fill_filespec(pair->one, tree->sha1, 1, tree->ce_mode);
383 return;
384 }
385 /*
387 * Something added to the tree?
388 */
389 if (!tree) {
390 show_new_file(revs, idx, cached, match_missing);
391 return;
392 }
393 /*
395 * Something removed from the tree?
396 */
397 if (!idx) {
398 diff_index_show_file(revs, "-", tree, tree->sha1, 1, tree->ce_mode, 0);
399 return;
400 }
401 /* Show difference between old and new */
403 show_modified(revs, tree, idx, 1, cached, match_missing);
404}
405/*
407 * The unpack_trees() interface is designed for merging, so
408 * the different source entries are designed primarily for
409 * the source trees, with the old index being really mainly
410 * used for being replaced by the result.
411 *
412 * For diffing, the index is more important, and we only have a
413 * single tree.
414 *
415 * We're supposed to advance o->pos to skip what we have already processed.
416 *
417 * This wrapper makes it all more readable, and takes care of all
418 * the fairly complex unpack_trees() semantic requirements, including
419 * the skipping, the path matching, the type conflict cases etc.
420 */
421static int oneway_diff(struct cache_entry **src, struct unpack_trees_options *o)
422{
423 struct cache_entry *idx = src[0];
424 struct cache_entry *tree = src[1];
425 struct rev_info *revs = o->unpack_data;
426 /*
428 * Unpack-trees generates a DF/conflict entry if
429 * there was a directory in the index and a tree
430 * in the tree. From a diff standpoint, that's a
431 * delete of the tree and a create of the file.
432 */
433 if (tree == o->df_conflict_entry)
434 tree = NULL;
435 if (ce_path_match(idx ? idx : tree, &revs->prune_data)) {
437 do_oneway_diff(o, idx, tree);
438 if (diff_can_quit_early(&revs->diffopt)) {
439 o->exiting_early = 1;
440 return -1;
441 }
442 }
443 return 0;
445}
446static int diff_cache(struct rev_info *revs,
448 const unsigned char *tree_sha1,
449 const char *tree_name,
450 int cached)
451{
452 struct tree *tree;
453 struct tree_desc t;
454 struct unpack_trees_options opts;
455 tree = parse_tree_indirect(tree_sha1);
457 if (!tree)
458 return error("bad tree object %s",
459 tree_name ? tree_name : sha1_to_hex(tree_sha1));
460 memset(&opts, 0, sizeof(opts));
461 opts.head_idx = 1;
462 opts.index_only = cached;
463 opts.diff_index_cached = (cached &&
464 !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER));
465 opts.merge = 1;
466 opts.fn = oneway_diff;
467 opts.unpack_data = revs;
468 opts.src_index = &the_index;
469 opts.dst_index = NULL;
470 opts.pathspec = &revs->diffopt.pathspec;
471 opts.pathspec->recursive = 1;
472 opts.pathspec->max_depth = -1;
473 init_tree_desc(&t, tree->buffer, tree->size);
475 return unpack_trees(1, &t, &opts);
476}
477int run_diff_index(struct rev_info *revs, int cached)
479{
480 struct object_array_entry *ent;
481 ent = revs->pending.objects;
483 if (diff_cache(revs, ent->item->sha1, ent->name, cached))
484 exit(128);
485 diff_set_mnemonic_prefix(&revs->diffopt, "c/", cached ? "i/" : "w/");
487 diffcore_fix_diff_index(&revs->diffopt);
488 diffcore_std(&revs->diffopt);
489 diff_flush(&revs->diffopt);
490 return 0;
491}
492int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
494{
495 struct rev_info revs;
496 init_revisions(&revs, NULL);
498 init_pathspec(&revs.prune_data, opt->pathspec.raw);
499 revs.diffopt = *opt;
500 if (diff_cache(&revs, tree_sha1, NULL, 1))
502 exit(128);
503 return 0;
504}
505int index_differs_from(const char *def, int diff_flags)
507{
508 struct rev_info rev;
509 struct setup_revision_opt opt;
510 init_revisions(&rev, NULL);
512 memset(&opt, 0, sizeof(opt));
513 opt.def = def;
514 setup_revisions(0, NULL, &rev, &opt);
515 DIFF_OPT_SET(&rev.diffopt, QUICK);
516 DIFF_OPT_SET(&rev.diffopt, EXIT_WITH_STATUS);
517 rev.diffopt.flags |= diff_flags;
518 run_diff_index(&rev, 1);
519 if (rev.pending.alloc)
520 free(rev.pending.objects);
521 return (DIFF_OPT_TST(&rev.diffopt, HAS_CHANGES) != 0);
522}