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 if (option & DIFF_SILENT_ON_REMOVED)
95 handle_deprecated_show_diff_q(&revs->diffopt);
96 diff_set_mnemonic_prefix(&revs->diffopt, "i/", "w/");
98 if (diff_unmerged_stage < 0)
100 diff_unmerged_stage = 2;
101 entries = active_nr;
102 for (i = 0; i < entries; i++) {
103 struct stat st;
104 unsigned int oldmode, newmode;
105 struct cache_entry *ce = active_cache[i];
106 int changed;
107 unsigned dirty_submodule = 0;
108 if (diff_can_quit_early(&revs->diffopt))
110 break;
111 if (!ce_path_match(ce, &revs->prune_data, NULL))
113 continue;
114 if (ce_stage(ce)) {
116 struct combine_diff_path *dpath;
117 struct diff_filepair *pair;
118 unsigned int wt_mode = 0;
119 int num_compare_stages = 0;
120 size_t path_len;
121 path_len = ce_namelen(ce);
123 dpath = xmalloc(combine_diff_path_size(5, path_len));
125 dpath->path = (char *) &(dpath->parent[5]);
126 dpath->next = NULL;
128 dpath->len = path_len;
129 memcpy(dpath->path, ce->name, path_len);
130 dpath->path[path_len] = '\0';
131 hashclr(dpath->sha1);
132 memset(&(dpath->parent[0]), 0,
133 sizeof(struct combine_diff_parent)*5);
134 changed = check_removed(ce, &st);
136 if (!changed)
137 wt_mode = ce_mode_from_stat(ce, st.st_mode);
138 else {
139 if (changed < 0) {
140 perror(ce->name);
141 continue;
142 }
143 wt_mode = 0;
144 }
145 dpath->mode = wt_mode;
146 while (i < entries) {
148 struct cache_entry *nce = active_cache[i];
149 int stage;
150 if (strcmp(ce->name, nce->name))
152 break;
153 /* Stage #2 (ours) is the first parent,
155 * stage #3 (theirs) is the second.
156 */
157 stage = ce_stage(nce);
158 if (2 <= stage) {
159 int mode = nce->ce_mode;
160 num_compare_stages++;
161 hashcpy(dpath->parent[stage-2].sha1, nce->sha1);
162 dpath->parent[stage-2].mode = ce_mode_from_stat(nce, mode);
163 dpath->parent[stage-2].status =
164 DIFF_STATUS_MODIFIED;
165 }
166 /* diff against the proper unmerged stage */
168 if (stage == diff_unmerged_stage)
169 ce = nce;
170 i++;
171 }
172 /*
173 * Compensate for loop update
174 */
175 i--;
176 if (revs->combine_merges && num_compare_stages == 2) {
178 show_combined_diff(dpath, 2,
179 revs->dense_combined_merges,
180 revs);
181 free(dpath);
182 continue;
183 }
184 free(dpath);
185 dpath = NULL;
186 /*
188 * Show the diff for the 'ce' if we found the one
189 * from the desired stage.
190 */
191 pair = diff_unmerge(&revs->diffopt, ce->name);
192 if (wt_mode)
193 pair->two->mode = wt_mode;
194 if (ce_stage(ce) != diff_unmerged_stage)
195 continue;
196 }
197 if (ce_uptodate(ce) || ce_skip_worktree(ce))
199 continue;
200 /* If CE_VALID is set, don't look at workdir for file removal */
202 changed = (ce->ce_flags & CE_VALID) ? 0 : check_removed(ce, &st);
203 if (changed) {
204 if (changed < 0) {
205 perror(ce->name);
206 continue;
207 }
208 diff_addremove(&revs->diffopt, '-', ce->ce_mode,
209 ce->sha1, !is_null_sha1(ce->sha1),
210 ce->name, 0);
211 continue;
212 }
213 changed = match_stat_with_submodule(&revs->diffopt, ce, &st,
214 ce_option, &dirty_submodule);
215 if (!changed && !dirty_submodule) {
216 ce_mark_uptodate(ce);
217 if (!DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
218 continue;
219 }
220 oldmode = ce->ce_mode;
221 newmode = ce_mode_from_stat(ce, st.st_mode);
222 diff_change(&revs->diffopt, oldmode, newmode,
223 ce->sha1, (changed ? null_sha1 : ce->sha1),
224 !is_null_sha1(ce->sha1), (changed ? 0 : !is_null_sha1(ce->sha1)),
225 ce->name, 0, dirty_submodule);
226 }
228 diffcore_std(&revs->diffopt);
229 diff_flush(&revs->diffopt);
230 return 0;
231}
232/*
234 * diff-index
235 */
236/* A file entry went away or appeared */
238static void diff_index_show_file(struct rev_info *revs,
239 const char *prefix,
240 const struct cache_entry *ce,
241 const unsigned char *sha1, int sha1_valid,
242 unsigned int mode,
243 unsigned dirty_submodule)
244{
245 diff_addremove(&revs->diffopt, prefix[0], mode,
246 sha1, sha1_valid, ce->name, dirty_submodule);
247}
248static int get_stat_data(const struct cache_entry *ce,
250 const unsigned char **sha1p,
251 unsigned int *modep,
252 int cached, int match_missing,
253 unsigned *dirty_submodule, struct diff_options *diffopt)
254{
255 const unsigned char *sha1 = ce->sha1;
256 unsigned int mode = ce->ce_mode;
257 if (!cached && !ce_uptodate(ce)) {
259 int changed;
260 struct stat st;
261 changed = check_removed(ce, &st);
262 if (changed < 0)
263 return -1;
264 else if (changed) {
265 if (match_missing) {
266 *sha1p = sha1;
267 *modep = mode;
268 return 0;
269 }
270 return -1;
271 }
272 changed = match_stat_with_submodule(diffopt, ce, &st,
273 0, dirty_submodule);
274 if (changed) {
275 mode = ce_mode_from_stat(ce, st.st_mode);
276 sha1 = null_sha1;
277 }
278 }
279 *sha1p = sha1;
281 *modep = mode;
282 return 0;
283}
284static void show_new_file(struct rev_info *revs,
286 const struct cache_entry *new,
287 int cached, int match_missing)
288{
289 const unsigned char *sha1;
290 unsigned int mode;
291 unsigned dirty_submodule = 0;
292 /*
294 * New file in the index: it might actually be different in
295 * the working tree.
296 */
297 if (get_stat_data(new, &sha1, &mode, cached, match_missing,
298 &dirty_submodule, &revs->diffopt) < 0)
299 return;
300 diff_index_show_file(revs, "+", new, sha1, !is_null_sha1(sha1), mode, dirty_submodule);
302}
303static int show_modified(struct rev_info *revs,
305 const struct cache_entry *old,
306 const struct cache_entry *new,
307 int report_missing,
308 int cached, int match_missing)
309{
310 unsigned int mode, oldmode;
311 const unsigned char *sha1;
312 unsigned dirty_submodule = 0;
313 if (get_stat_data(new, &sha1, &mode, cached, match_missing,
315 &dirty_submodule, &revs->diffopt) < 0) {
316 if (report_missing)
317 diff_index_show_file(revs, "-", old,
318 old->sha1, 1, old->ce_mode, 0);
319 return -1;
320 }
321 if (revs->combine_merges && !cached &&
323 (hashcmp(sha1, old->sha1) || hashcmp(old->sha1, new->sha1))) {
324 struct combine_diff_path *p;
325 int pathlen = ce_namelen(new);
326 p = xmalloc(combine_diff_path_size(2, pathlen));
328 p->path = (char *) &p->parent[2];
329 p->next = NULL;
330 p->len = pathlen;
331 memcpy(p->path, new->name, pathlen);
332 p->path[pathlen] = 0;
333 p->mode = mode;
334 hashclr(p->sha1);
335 memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
336 p->parent[0].status = DIFF_STATUS_MODIFIED;
337 p->parent[0].mode = new->ce_mode;
338 hashcpy(p->parent[0].sha1, new->sha1);
339 p->parent[1].status = DIFF_STATUS_MODIFIED;
340 p->parent[1].mode = old->ce_mode;
341 hashcpy(p->parent[1].sha1, old->sha1);
342 show_combined_diff(p, 2, revs->dense_combined_merges, revs);
343 free(p);
344 return 0;
345 }
346 oldmode = old->ce_mode;
348 if (mode == oldmode && !hashcmp(sha1, old->sha1) && !dirty_submodule &&
349 !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
350 return 0;
351 diff_change(&revs->diffopt, oldmode, mode,
353 old->sha1, sha1, 1, !is_null_sha1(sha1),
354 old->name, 0, dirty_submodule);
355 return 0;
356}
357/*
359 * This gets a mix of an existing index and a tree, one pathname entry
360 * at a time. The index entry may be a single stage-0 one, but it could
361 * also be multiple unmerged entries (in which case idx_pos/idx_nr will
362 * give you the position and number of entries in the index).
363 */
364static void do_oneway_diff(struct unpack_trees_options *o,
365 const struct cache_entry *idx,
366 const struct cache_entry *tree)
367{
368 struct rev_info *revs = o->unpack_data;
369 int match_missing, cached;
370 /* if the entry is not checked out, don't examine work tree */
372 cached = o->index_only ||
373 (idx && ((idx->ce_flags & CE_VALID) || ce_skip_worktree(idx)));
374 /*
375 * Backward compatibility wart - "diff-index -m" does
376 * not mean "do not ignore merges", but "match_missing".
377 *
378 * But with the revision flag parsing, that's found in
379 * "!revs->ignore_merges".
380 */
381 match_missing = !revs->ignore_merges;
382 if (cached && idx && ce_stage(idx)) {
384 struct diff_filepair *pair;
385 pair = diff_unmerge(&revs->diffopt, idx->name);
386 if (tree)
387 fill_filespec(pair->one, tree->sha1, 1, tree->ce_mode);
388 return;
389 }
390 /*
392 * Something added to the tree?
393 */
394 if (!tree) {
395 show_new_file(revs, idx, cached, match_missing);
396 return;
397 }
398 /*
400 * Something removed from the tree?
401 */
402 if (!idx) {
403 diff_index_show_file(revs, "-", tree, tree->sha1, 1, tree->ce_mode, 0);
404 return;
405 }
406 /* Show difference between old and new */
408 show_modified(revs, tree, idx, 1, cached, match_missing);
409}
410/*
412 * The unpack_trees() interface is designed for merging, so
413 * the different source entries are designed primarily for
414 * the source trees, with the old index being really mainly
415 * used for being replaced by the result.
416 *
417 * For diffing, the index is more important, and we only have a
418 * single tree.
419 *
420 * We're supposed to advance o->pos to skip what we have already processed.
421 *
422 * This wrapper makes it all more readable, and takes care of all
423 * the fairly complex unpack_trees() semantic requirements, including
424 * the skipping, the path matching, the type conflict cases etc.
425 */
426static int oneway_diff(const struct cache_entry * const *src,
427 struct unpack_trees_options *o)
428{
429 const struct cache_entry *idx = src[0];
430 const struct cache_entry *tree = src[1];
431 struct rev_info *revs = o->unpack_data;
432 /*
434 * Unpack-trees generates a DF/conflict entry if
435 * there was a directory in the index and a tree
436 * in the tree. From a diff standpoint, that's a
437 * delete of the tree and a create of the file.
438 */
439 if (tree == o->df_conflict_entry)
440 tree = NULL;
441 if (ce_path_match(idx ? idx : tree, &revs->prune_data, NULL)) {
443 do_oneway_diff(o, idx, tree);
444 if (diff_can_quit_early(&revs->diffopt)) {
445 o->exiting_early = 1;
446 return -1;
447 }
448 }
449 return 0;
451}
452static int diff_cache(struct rev_info *revs,
454 const unsigned char *tree_sha1,
455 const char *tree_name,
456 int cached)
457{
458 struct tree *tree;
459 struct tree_desc t;
460 struct unpack_trees_options opts;
461 tree = parse_tree_indirect(tree_sha1);
463 if (!tree)
464 return error("bad tree object %s",
465 tree_name ? tree_name : sha1_to_hex(tree_sha1));
466 memset(&opts, 0, sizeof(opts));
467 opts.head_idx = 1;
468 opts.index_only = cached;
469 opts.diff_index_cached = (cached &&
470 !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER));
471 opts.merge = 1;
472 opts.fn = oneway_diff;
473 opts.unpack_data = revs;
474 opts.src_index = &the_index;
475 opts.dst_index = NULL;
476 opts.pathspec = &revs->diffopt.pathspec;
477 opts.pathspec->recursive = 1;
478 init_tree_desc(&t, tree->buffer, tree->size);
480 return unpack_trees(1, &t, &opts);
481}
482int run_diff_index(struct rev_info *revs, int cached)
484{
485 struct object_array_entry *ent;
486 ent = revs->pending.objects;
488 if (diff_cache(revs, ent->item->sha1, ent->name, cached))
489 exit(128);
490 diff_set_mnemonic_prefix(&revs->diffopt, "c/", cached ? "i/" : "w/");
492 diffcore_fix_diff_index(&revs->diffopt);
493 diffcore_std(&revs->diffopt);
494 diff_flush(&revs->diffopt);
495 return 0;
496}
497int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
499{
500 struct rev_info revs;
501 init_revisions(&revs, NULL);
503 copy_pathspec(&revs.prune_data, &opt->pathspec);
504 revs.diffopt = *opt;
505 if (diff_cache(&revs, tree_sha1, NULL, 1))
507 exit(128);
508 return 0;
509}
510int index_differs_from(const char *def, int diff_flags)
512{
513 struct rev_info rev;
514 struct setup_revision_opt opt;
515 init_revisions(&rev, NULL);
517 memset(&opt, 0, sizeof(opt));
518 opt.def = def;
519 setup_revisions(0, NULL, &rev, &opt);
520 DIFF_OPT_SET(&rev.diffopt, QUICK);
521 DIFF_OPT_SET(&rev.diffopt, EXIT_WITH_STATUS);
522 rev.diffopt.flags |= diff_flags;
523 run_diff_index(&rev, 1);
524 if (rev.pending.alloc)
525 free(rev.pending.objects);
526 return (DIFF_OPT_TST(&rev.diffopt, HAS_CHANGES) != 0);
527}