doc: describe git svn init --ignore-refs
[git/git-svn.git] / diff-lib.c
blob2982bf055acb6049a8cd6007244d60d985b7e619
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"
17 * diff-files
21 * Has the work tree entity been removed?
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.
29 static int check_removed(const struct cache_entry *ce, struct stat *st)
31 if (lstat(ce->name, st) < 0) {
32 if (errno != ENOENT && errno != ENOTDIR)
33 return -1;
34 return 1;
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];
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.
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!
52 if (!S_ISGITLINK(ce->ce_mode) &&
53 resolve_gitlink_ref(ce->name, "HEAD", sub))
54 return 1;
56 return 0;
60 * Has a file changed or has a submodule new commits or a dirty work tree?
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).
67 static 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)
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;
84 return changed;
87 int run_diff_files(struct rev_info *revs, unsigned int option)
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);
94 diff_set_mnemonic_prefix(&revs->diffopt, "i/", "w/");
96 if (diff_unmerged_stage < 0)
97 diff_unmerged_stage = 2;
98 entries = active_nr;
99 for (i = 0; i < entries; i++) {
100 unsigned int oldmode, newmode;
101 struct cache_entry *ce = active_cache[i];
102 int changed;
103 unsigned dirty_submodule = 0;
104 const unsigned char *old_sha1, *new_sha1;
106 if (diff_can_quit_early(&revs->diffopt))
107 break;
109 if (!ce_path_match(ce, &revs->prune_data, NULL))
110 continue;
112 if (ce_stage(ce)) {
113 struct combine_diff_path *dpath;
114 struct diff_filepair *pair;
115 unsigned int wt_mode = 0;
116 int num_compare_stages = 0;
117 size_t path_len;
118 struct stat st;
120 path_len = ce_namelen(ce);
122 dpath = xmalloc(combine_diff_path_size(5, path_len));
123 dpath->path = (char *) &(dpath->parent[5]);
125 dpath->next = NULL;
126 memcpy(dpath->path, ce->name, path_len);
127 dpath->path[path_len] = '\0';
128 oidclr(&dpath->oid);
129 memset(&(dpath->parent[0]), 0,
130 sizeof(struct combine_diff_parent)*5);
132 changed = check_removed(ce, &st);
133 if (!changed)
134 wt_mode = ce_mode_from_stat(ce, st.st_mode);
135 else {
136 if (changed < 0) {
137 perror(ce->name);
138 continue;
140 wt_mode = 0;
142 dpath->mode = wt_mode;
144 while (i < entries) {
145 struct cache_entry *nce = active_cache[i];
146 int stage;
148 if (strcmp(ce->name, nce->name))
149 break;
151 /* Stage #2 (ours) is the first parent,
152 * stage #3 (theirs) is the second.
154 stage = ce_stage(nce);
155 if (2 <= stage) {
156 int mode = nce->ce_mode;
157 num_compare_stages++;
158 oidcpy(&dpath->parent[stage - 2].oid,
159 &nce->oid);
160 dpath->parent[stage-2].mode = ce_mode_from_stat(nce, mode);
161 dpath->parent[stage-2].status =
162 DIFF_STATUS_MODIFIED;
165 /* diff against the proper unmerged stage */
166 if (stage == diff_unmerged_stage)
167 ce = nce;
168 i++;
171 * Compensate for loop update
173 i--;
175 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;
182 free(dpath);
183 dpath = NULL;
186 * Show the diff for the 'ce' if we found the one
187 * from the desired stage.
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;
196 if (ce_uptodate(ce) || ce_skip_worktree(ce))
197 continue;
199 /* If CE_VALID is set, don't look at workdir for file removal */
200 if (ce->ce_flags & CE_VALID) {
201 changed = 0;
202 newmode = ce->ce_mode;
203 } else {
204 struct stat st;
206 changed = check_removed(ce, &st);
207 if (changed) {
208 if (changed < 0) {
209 perror(ce->name);
210 continue;
212 diff_addremove(&revs->diffopt, '-', ce->ce_mode,
213 ce->oid.hash,
214 !is_null_oid(&ce->oid),
215 ce->name, 0);
216 continue;
217 } else if (revs->diffopt.ita_invisible_in_index &&
218 ce_intent_to_add(ce)) {
219 diff_addremove(&revs->diffopt, '+', ce->ce_mode,
220 EMPTY_BLOB_SHA1_BIN, 0,
221 ce->name, 0);
222 continue;
225 changed = match_stat_with_submodule(&revs->diffopt, ce, &st,
226 ce_option, &dirty_submodule);
227 newmode = ce_mode_from_stat(ce, st.st_mode);
230 if (!changed && !dirty_submodule) {
231 ce_mark_uptodate(ce);
232 if (!DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
233 continue;
235 oldmode = ce->ce_mode;
236 old_sha1 = ce->oid.hash;
237 new_sha1 = changed ? null_sha1 : ce->oid.hash;
238 diff_change(&revs->diffopt, oldmode, newmode,
239 old_sha1, new_sha1,
240 !is_null_sha1(old_sha1),
241 !is_null_sha1(new_sha1),
242 ce->name, 0, dirty_submodule);
245 diffcore_std(&revs->diffopt);
246 diff_flush(&revs->diffopt);
247 return 0;
251 * diff-index
254 /* A file entry went away or appeared */
255 static void diff_index_show_file(struct rev_info *revs,
256 const char *prefix,
257 const struct cache_entry *ce,
258 const unsigned char *sha1, int sha1_valid,
259 unsigned int mode,
260 unsigned dirty_submodule)
262 diff_addremove(&revs->diffopt, prefix[0], mode,
263 sha1, sha1_valid, ce->name, dirty_submodule);
266 static int get_stat_data(const struct cache_entry *ce,
267 const unsigned char **sha1p,
268 unsigned int *modep,
269 int cached, int match_missing,
270 unsigned *dirty_submodule, struct diff_options *diffopt)
272 const unsigned char *sha1 = ce->oid.hash;
273 unsigned int mode = ce->ce_mode;
275 if (!cached && !ce_uptodate(ce)) {
276 int changed;
277 struct stat st;
278 changed = check_removed(ce, &st);
279 if (changed < 0)
280 return -1;
281 else if (changed) {
282 if (match_missing) {
283 *sha1p = sha1;
284 *modep = mode;
285 return 0;
287 return -1;
289 changed = match_stat_with_submodule(diffopt, ce, &st,
290 0, dirty_submodule);
291 if (changed) {
292 mode = ce_mode_from_stat(ce, st.st_mode);
293 sha1 = null_sha1;
297 *sha1p = sha1;
298 *modep = mode;
299 return 0;
302 static void show_new_file(struct rev_info *revs,
303 const struct cache_entry *new,
304 int cached, int match_missing)
306 const unsigned char *sha1;
307 unsigned int mode;
308 unsigned dirty_submodule = 0;
311 * New file in the index: it might actually be different in
312 * the working tree.
314 if (get_stat_data(new, &sha1, &mode, cached, match_missing,
315 &dirty_submodule, &revs->diffopt) < 0)
316 return;
318 diff_index_show_file(revs, "+", new, sha1, !is_null_sha1(sha1), mode, dirty_submodule);
321 static int show_modified(struct rev_info *revs,
322 const struct cache_entry *old,
323 const struct cache_entry *new,
324 int report_missing,
325 int cached, int match_missing)
327 unsigned int mode, oldmode;
328 const unsigned char *sha1;
329 unsigned dirty_submodule = 0;
331 if (get_stat_data(new, &sha1, &mode, cached, match_missing,
332 &dirty_submodule, &revs->diffopt) < 0) {
333 if (report_missing)
334 diff_index_show_file(revs, "-", old,
335 old->oid.hash, 1, old->ce_mode,
337 return -1;
340 if (revs->combine_merges && !cached &&
341 (hashcmp(sha1, old->oid.hash) || oidcmp(&old->oid, &new->oid))) {
342 struct combine_diff_path *p;
343 int pathlen = ce_namelen(new);
345 p = xmalloc(combine_diff_path_size(2, pathlen));
346 p->path = (char *) &p->parent[2];
347 p->next = NULL;
348 memcpy(p->path, new->name, pathlen);
349 p->path[pathlen] = 0;
350 p->mode = mode;
351 oidclr(&p->oid);
352 memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
353 p->parent[0].status = DIFF_STATUS_MODIFIED;
354 p->parent[0].mode = new->ce_mode;
355 oidcpy(&p->parent[0].oid, &new->oid);
356 p->parent[1].status = DIFF_STATUS_MODIFIED;
357 p->parent[1].mode = old->ce_mode;
358 oidcpy(&p->parent[1].oid, &old->oid);
359 show_combined_diff(p, 2, revs->dense_combined_merges, revs);
360 free(p);
361 return 0;
364 oldmode = old->ce_mode;
365 if (mode == oldmode && !hashcmp(sha1, old->oid.hash) && !dirty_submodule &&
366 !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
367 return 0;
369 diff_change(&revs->diffopt, oldmode, mode,
370 old->oid.hash, sha1, 1, !is_null_sha1(sha1),
371 old->name, 0, dirty_submodule);
372 return 0;
376 * This gets a mix of an existing index and a tree, one pathname entry
377 * at a time. The index entry may be a single stage-0 one, but it could
378 * also be multiple unmerged entries (in which case idx_pos/idx_nr will
379 * give you the position and number of entries in the index).
381 static void do_oneway_diff(struct unpack_trees_options *o,
382 const struct cache_entry *idx,
383 const struct cache_entry *tree)
385 struct rev_info *revs = o->unpack_data;
386 int match_missing, cached;
388 /* i-t-a entries do not actually exist in the index */
389 if (revs->diffopt.ita_invisible_in_index &&
390 idx && ce_intent_to_add(idx)) {
391 idx = NULL;
392 if (!tree)
393 return; /* nothing to diff.. */
396 /* if the entry is not checked out, don't examine work tree */
397 cached = o->index_only ||
398 (idx && ((idx->ce_flags & CE_VALID) || ce_skip_worktree(idx)));
400 * Backward compatibility wart - "diff-index -m" does
401 * not mean "do not ignore merges", but "match_missing".
403 * But with the revision flag parsing, that's found in
404 * "!revs->ignore_merges".
406 match_missing = !revs->ignore_merges;
408 if (cached && idx && ce_stage(idx)) {
409 struct diff_filepair *pair;
410 pair = diff_unmerge(&revs->diffopt, idx->name);
411 if (tree)
412 fill_filespec(pair->one, tree->oid.hash, 1,
413 tree->ce_mode);
414 return;
418 * Something added to the tree?
420 if (!tree) {
421 show_new_file(revs, idx, cached, match_missing);
422 return;
426 * Something removed from the tree?
428 if (!idx) {
429 diff_index_show_file(revs, "-", tree, tree->oid.hash, 1,
430 tree->ce_mode, 0);
431 return;
434 /* Show difference between old and new */
435 show_modified(revs, tree, idx, 1, cached, match_missing);
439 * The unpack_trees() interface is designed for merging, so
440 * the different source entries are designed primarily for
441 * the source trees, with the old index being really mainly
442 * used for being replaced by the result.
444 * For diffing, the index is more important, and we only have a
445 * single tree.
447 * We're supposed to advance o->pos to skip what we have already processed.
449 * This wrapper makes it all more readable, and takes care of all
450 * the fairly complex unpack_trees() semantic requirements, including
451 * the skipping, the path matching, the type conflict cases etc.
453 static int oneway_diff(const struct cache_entry * const *src,
454 struct unpack_trees_options *o)
456 const struct cache_entry *idx = src[0];
457 const struct cache_entry *tree = src[1];
458 struct rev_info *revs = o->unpack_data;
461 * Unpack-trees generates a DF/conflict entry if
462 * there was a directory in the index and a tree
463 * in the tree. From a diff standpoint, that's a
464 * delete of the tree and a create of the file.
466 if (tree == o->df_conflict_entry)
467 tree = NULL;
469 if (ce_path_match(idx ? idx : tree, &revs->prune_data, NULL)) {
470 do_oneway_diff(o, idx, tree);
471 if (diff_can_quit_early(&revs->diffopt)) {
472 o->exiting_early = 1;
473 return -1;
477 return 0;
480 static int diff_cache(struct rev_info *revs,
481 const struct object_id *tree_oid,
482 const char *tree_name,
483 int cached)
485 struct tree *tree;
486 struct tree_desc t;
487 struct unpack_trees_options opts;
489 tree = parse_tree_indirect(tree_oid);
490 if (!tree)
491 return error("bad tree object %s",
492 tree_name ? tree_name : oid_to_hex(tree_oid));
493 memset(&opts, 0, sizeof(opts));
494 opts.head_idx = 1;
495 opts.index_only = cached;
496 opts.diff_index_cached = (cached &&
497 !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER));
498 opts.merge = 1;
499 opts.fn = oneway_diff;
500 opts.unpack_data = revs;
501 opts.src_index = &the_index;
502 opts.dst_index = NULL;
503 opts.pathspec = &revs->diffopt.pathspec;
504 opts.pathspec->recursive = 1;
506 init_tree_desc(&t, tree->buffer, tree->size);
507 return unpack_trees(1, &t, &opts);
510 int run_diff_index(struct rev_info *revs, int cached)
512 struct object_array_entry *ent;
514 ent = revs->pending.objects;
515 if (diff_cache(revs, &ent->item->oid, ent->name, cached))
516 exit(128);
518 diff_set_mnemonic_prefix(&revs->diffopt, "c/", cached ? "i/" : "w/");
519 diffcore_fix_diff_index(&revs->diffopt);
520 diffcore_std(&revs->diffopt);
521 diff_flush(&revs->diffopt);
522 return 0;
525 int do_diff_cache(const struct object_id *tree_oid, struct diff_options *opt)
527 struct rev_info revs;
529 init_revisions(&revs, NULL);
530 copy_pathspec(&revs.prune_data, &opt->pathspec);
531 revs.diffopt = *opt;
533 if (diff_cache(&revs, tree_oid, NULL, 1))
534 exit(128);
535 return 0;
538 int index_differs_from(const char *def, int diff_flags,
539 int ita_invisible_in_index)
541 struct rev_info rev;
542 struct setup_revision_opt opt;
544 init_revisions(&rev, NULL);
545 memset(&opt, 0, sizeof(opt));
546 opt.def = def;
547 setup_revisions(0, NULL, &rev, &opt);
548 DIFF_OPT_SET(&rev.diffopt, QUICK);
549 DIFF_OPT_SET(&rev.diffopt, EXIT_WITH_STATUS);
550 rev.diffopt.flags |= diff_flags;
551 rev.diffopt.ita_invisible_in_index = ita_invisible_in_index;
552 run_diff_index(&rev, 1);
553 if (rev.pending.alloc)
554 free(rev.pending.objects);
555 return (DIFF_OPT_TST(&rev.diffopt, HAS_CHANGES) != 0);