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 int silent_on_removed = option & DIFF_SILENT_ON_REMOVED;
90 unsigned ce_option = ((option & DIFF_RACY_IS_MODIFIED)
91 ? CE_MATCH_RACY_IS_DIRTY : 0);
92 diff_set_mnemonic_prefix(&revs->diffopt, "i/", "w/");
94 if (diff_unmerged_stage < 0)
96 diff_unmerged_stage = 2;
97 entries = active_nr;
98 for (i = 0; i < entries; i++) {
99 struct stat st;
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))
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 path_len = ce_namelen(ce);
119 dpath = xmalloc(combine_diff_path_size(5, path_len));
121 dpath->path = (char *) &(dpath->parent[5]);
122 dpath->next = NULL;
124 dpath->len = path_len;
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 if (silent_on_removed)
140 continue;
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 if (silent_on_removed)
207 continue;
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 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(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 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 struct cache_entry *old,
306 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 struct cache_entry *idx,
366 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(struct cache_entry **src, struct unpack_trees_options *o)
427{
428 struct cache_entry *idx = src[0];
429 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 opts.pathspec->max_depth = -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 init_pathspec(&revs.prune_data, opt->pathspec.raw);
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}