unpack-trees.c: prepare for looking ahead in the index
[git/git.git] / diff-lib.c
CommitLineData
be3cfa85
JH
1/*
2 * Copyright (C) 2005 Junio C Hamano
3 */
86436c28 4#include "cache.h"
6fb737be 5#include "quote.h"
6973dcae 6#include "commit.h"
86436c28 7#include "diff.h"
427dcb4b 8#include "diffcore.h"
6973dcae 9#include "revision.h"
1cfe7733 10#include "cache-tree.h"
d1f2d7e8 11#include "unpack-trees.h"
948dd346 12#include "refs.h"
427dcb4b 13
b46f0b6d 14/*
6973dcae 15 * diff-files
b46f0b6d 16 */
f0c6b2a2 17
948dd346 18/*
1392a377
JH
19 * Has the work tree entity been removed?
20 *
21 * Return 1 if it was removed from the work tree, 0 if an entity to be
22 * compared with the cache entry ce still exists (the latter includes
23 * the case where a directory that is not a submodule repository
24 * exists for ce that is a submodule -- it is a submodule that is not
25 * checked out). Return negative for an error.
948dd346 26 */
c40641b7 27static int check_removed(const struct cache_entry *ce, struct stat *st)
948dd346
JH
28{
29 if (lstat(ce->name, st) < 0) {
30 if (errno != ENOENT && errno != ENOTDIR)
31 return -1;
32 return 1;
33 }
57199892 34 if (has_symlink_leading_path(ce->name, ce_namelen(ce)))
948dd346
JH
35 return 1;
36 if (S_ISDIR(st->st_mode)) {
37 unsigned char sub[20];
1392a377
JH
38
39 /*
40 * If ce is already a gitlink, we can have a plain
41 * directory (i.e. the submodule is not checked out),
42 * or a checked out submodule. Either case this is not
43 * a case where something was removed from the work tree,
44 * so we will return 0.
45 *
46 * Otherwise, if the directory is not a submodule
47 * repository, that means ce which was a blob turned into
48 * a directory --- the blob was removed!
49 */
50 if (!S_ISGITLINK(ce->ce_mode) &&
51 resolve_gitlink_ref(ce->name, "HEAD", sub))
948dd346
JH
52 return 1;
53 }
54 return 0;
55}
d516c2d1 56
4bd5b7da 57int run_diff_files(struct rev_info *revs, unsigned int option)
f0c6b2a2 58{
6973dcae
JH
59 int entries, i;
60 int diff_unmerged_stage = revs->max_count;
4bd5b7da 61 int silent_on_removed = option & DIFF_SILENT_ON_REMOVED;
fb63d7f8
JH
62 unsigned ce_option = ((option & DIFF_RACY_IS_MODIFIED)
63 ? CE_MATCH_RACY_IS_DIRTY : 0);
f0c6b2a2 64
a5a818ee
JH
65 diff_set_mnemonic_prefix(&revs->diffopt, "i/", "w/");
66
6973dcae
JH
67 if (diff_unmerged_stage < 0)
68 diff_unmerged_stage = 2;
b4e1e4a7 69 entries = active_nr;
6973dcae 70 for (i = 0; i < entries; i++) {
be3cfa85 71 struct stat st;
6973dcae
JH
72 unsigned int oldmode, newmode;
73 struct cache_entry *ce = active_cache[i];
74 int changed;
8676eb43 75
8f67f8ae
PH
76 if (DIFF_OPT_TST(&revs->diffopt, QUIET) &&
77 DIFF_OPT_TST(&revs->diffopt, HAS_CHANGES))
822cac01
JH
78 break;
79
6973dcae 80 if (!ce_path_match(ce, revs->prune_data))
8676eb43 81 continue;
be3cfa85 82
6973dcae 83 if (ce_stage(ce)) {
b4b15503 84 struct combine_diff_path *dpath;
6973dcae 85 int num_compare_stages = 0;
b4b15503 86 size_t path_len;
6973dcae 87
b4b15503
FF
88 path_len = ce_namelen(ce);
89
4fc970c4 90 dpath = xmalloc(combine_diff_path_size(5, path_len));
b4b15503
FF
91 dpath->path = (char *) &(dpath->parent[5]);
92
93 dpath->next = NULL;
94 dpath->len = path_len;
95 memcpy(dpath->path, ce->name, path_len);
96 dpath->path[path_len] = '\0';
a8e0d16d 97 hashclr(dpath->sha1);
b4b15503 98 memset(&(dpath->parent[0]), 0,
4fc970c4
JH
99 sizeof(struct combine_diff_parent)*5);
100
c40641b7 101 changed = check_removed(ce, &st);
f58dbf23
JH
102 if (!changed)
103 dpath->mode = ce_mode_from_stat(ce, st.st_mode);
104 else {
105 if (changed < 0) {
4fc970c4
JH
106 perror(ce->name);
107 continue;
108 }
109 if (silent_on_removed)
110 continue;
111 }
6973dcae
JH
112
113 while (i < entries) {
114 struct cache_entry *nce = active_cache[i];
115 int stage;
116
117 if (strcmp(ce->name, nce->name))
118 break;
119
120 /* Stage #2 (ours) is the first parent,
121 * stage #3 (theirs) is the second.
122 */
123 stage = ce_stage(nce);
124 if (2 <= stage) {
7a51ed66 125 int mode = nce->ce_mode;
6973dcae 126 num_compare_stages++;
e702496e 127 hashcpy(dpath->parent[stage-2].sha1, nce->sha1);
7a51ed66 128 dpath->parent[stage-2].mode = ce_mode_from_stat(nce, mode);
b4b15503 129 dpath->parent[stage-2].status =
6973dcae
JH
130 DIFF_STATUS_MODIFIED;
131 }
132
133 /* diff against the proper unmerged stage */
134 if (stage == diff_unmerged_stage)
135 ce = nce;
136 i++;
137 }
138 /*
139 * Compensate for loop update
f0c6b2a2 140 */
6973dcae 141 i--;
6b5ee137 142
6973dcae 143 if (revs->combine_merges && num_compare_stages == 2) {
b4b15503 144 show_combined_diff(dpath, 2,
6973dcae
JH
145 revs->dense_combined_merges,
146 revs);
b4b15503 147 free(dpath);
6973dcae 148 continue;
1b1480ff 149 }
b4b15503
FF
150 free(dpath);
151 dpath = NULL;
0e3994fa 152
6973dcae
JH
153 /*
154 * Show the diff for the 'ce' if we found the one
155 * from the desired stage.
156 */
e9c84099 157 diff_unmerge(&revs->diffopt, ce->name, 0, null_sha1);
6973dcae
JH
158 if (ce_stage(ce) != diff_unmerged_stage)
159 continue;
eeaa4603 160 }
6b14d7fa 161
d1f2d7e8
LT
162 if (ce_uptodate(ce))
163 continue;
f58dbf23 164
540e694b
NTND
165 /* If CE_VALID is set, don't look at workdir for file removal */
166 changed = (ce->ce_flags & CE_VALID) ? 0 : check_removed(ce, &st);
f58dbf23
JH
167 if (changed) {
168 if (changed < 0) {
6973dcae 169 perror(ce->name);
15d061b4
JH
170 continue;
171 }
6973dcae
JH
172 if (silent_on_removed)
173 continue;
7a51ed66 174 diff_addremove(&revs->diffopt, '-', ce->ce_mode,
fd55a19e 175 ce->sha1, ce->name);
6973dcae 176 continue;
f2ce9fde 177 }
fb63d7f8 178 changed = ce_match_stat(ce, &st, ce_option);
8fa29602
JH
179 if (!changed) {
180 ce_mark_uptodate(ce);
181 if (!DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
182 continue;
183 }
7a51ed66
LT
184 oldmode = ce->ce_mode;
185 newmode = ce_mode_from_stat(ce, st.st_mode);
6973dcae
JH
186 diff_change(&revs->diffopt, oldmode, newmode,
187 ce->sha1, (changed ? null_sha1 : ce->sha1),
fd55a19e 188 ce->name);
77eb2720 189
7ca45252 190 }
6973dcae
JH
191 diffcore_std(&revs->diffopt);
192 diff_flush(&revs->diffopt);
193 return 0;
77eb2720 194}
be3cfa85 195
e09ad6e1
JH
196/*
197 * diff-index
198 */
199
200/* A file entry went away or appeared */
201static void diff_index_show_file(struct rev_info *revs,
202 const char *prefix,
203 struct cache_entry *ce,
c8c16f28 204 const unsigned char *sha1, unsigned int mode)
e09ad6e1 205{
7a51ed66 206 diff_addremove(&revs->diffopt, prefix[0], mode,
fd55a19e 207 sha1, ce->name);
e09ad6e1
JH
208}
209
210static int get_stat_data(struct cache_entry *ce,
c8c16f28 211 const unsigned char **sha1p,
e09ad6e1 212 unsigned int *modep,
ff7e6aad 213 int cached, int match_missing)
e09ad6e1 214{
c8c16f28 215 const unsigned char *sha1 = ce->sha1;
e09ad6e1
JH
216 unsigned int mode = ce->ce_mode;
217
658dd48c 218 if (!cached && !ce_uptodate(ce)) {
e09ad6e1
JH
219 int changed;
220 struct stat st;
c40641b7 221 changed = check_removed(ce, &st);
948dd346
JH
222 if (changed < 0)
223 return -1;
224 else if (changed) {
225 if (match_missing) {
e09ad6e1
JH
226 *sha1p = sha1;
227 *modep = mode;
228 return 0;
229 }
230 return -1;
231 }
232 changed = ce_match_stat(ce, &st, 0);
233 if (changed) {
185c975f 234 mode = ce_mode_from_stat(ce, st.st_mode);
c8c16f28 235 sha1 = null_sha1;
e09ad6e1
JH
236 }
237 }
238
239 *sha1p = sha1;
240 *modep = mode;
241 return 0;
242}
243
ff7e6aad 244static void show_new_file(struct rev_info *revs,
e09ad6e1
JH
245 struct cache_entry *new,
246 int cached, int match_missing)
247{
c8c16f28 248 const unsigned char *sha1;
e09ad6e1
JH
249 unsigned int mode;
250
948dd346
JH
251 /*
252 * New file in the index: it might actually be different in
e09ad6e1
JH
253 * the working copy.
254 */
ff7e6aad 255 if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0)
e09ad6e1
JH
256 return;
257
258 diff_index_show_file(revs, "+", new, sha1, mode);
259}
260
ff7e6aad 261static int show_modified(struct rev_info *revs,
e09ad6e1
JH
262 struct cache_entry *old,
263 struct cache_entry *new,
264 int report_missing,
265 int cached, int match_missing)
266{
267 unsigned int mode, oldmode;
c8c16f28 268 const unsigned char *sha1;
e09ad6e1 269
ff7e6aad 270 if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0) {
e09ad6e1
JH
271 if (report_missing)
272 diff_index_show_file(revs, "-", old,
273 old->sha1, old->ce_mode);
274 return -1;
275 }
276
cb2b9f5e
PM
277 if (revs->combine_merges && !cached &&
278 (hashcmp(sha1, old->sha1) || hashcmp(old->sha1, new->sha1))) {
279 struct combine_diff_path *p;
280 int pathlen = ce_namelen(new);
281
282 p = xmalloc(combine_diff_path_size(2, pathlen));
283 p->path = (char *) &p->parent[2];
284 p->next = NULL;
285 p->len = pathlen;
286 memcpy(p->path, new->name, pathlen);
287 p->path[pathlen] = 0;
7a51ed66 288 p->mode = mode;
cb2b9f5e
PM
289 hashclr(p->sha1);
290 memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
291 p->parent[0].status = DIFF_STATUS_MODIFIED;
7a51ed66 292 p->parent[0].mode = new->ce_mode;
cb2b9f5e
PM
293 hashcpy(p->parent[0].sha1, new->sha1);
294 p->parent[1].status = DIFF_STATUS_MODIFIED;
7a51ed66 295 p->parent[1].mode = old->ce_mode;
cb2b9f5e
PM
296 hashcpy(p->parent[1].sha1, old->sha1);
297 show_combined_diff(p, 2, revs->dense_combined_merges, revs);
298 free(p);
299 return 0;
300 }
301
e09ad6e1 302 oldmode = old->ce_mode;
a89fccd2 303 if (mode == oldmode && !hashcmp(sha1, old->sha1) &&
8f67f8ae 304 !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
e09ad6e1
JH
305 return 0;
306
e09ad6e1 307 diff_change(&revs->diffopt, oldmode, mode,
fd55a19e 308 old->sha1, sha1, old->name);
e09ad6e1
JH
309 return 0;
310}
311
d1f2d7e8
LT
312/*
313 * This gets a mix of an existing index and a tree, one pathname entry
314 * at a time. The index entry may be a single stage-0 one, but it could
315 * also be multiple unmerged entries (in which case idx_pos/idx_nr will
316 * give you the position and number of entries in the index).
317 */
318static void do_oneway_diff(struct unpack_trees_options *o,
319 struct cache_entry *idx,
34110cd4 320 struct cache_entry *tree)
e09ad6e1 321{
ff7e6aad 322 struct rev_info *revs = o->unpack_data;
d1f2d7e8 323 int match_missing, cached;
5c21ac0e 324
540e694b
NTND
325 /* if the entry is not checked out, don't examine work tree */
326 cached = o->index_only || (idx && (idx->ce_flags & CE_VALID));
a6080a0a 327 /*
5c21ac0e 328 * Backward compatibility wart - "diff-index -m" does
d1f2d7e8
LT
329 * not mean "do not ignore merges", but "match_missing".
330 *
331 * But with the revision flag parsing, that's found in
332 * "!revs->ignore_merges".
333 */
d1f2d7e8
LT
334 match_missing = !revs->ignore_merges;
335
336 if (cached && idx && ce_stage(idx)) {
29796c6c
JH
337 diff_unmerge(&revs->diffopt, idx->name, idx->ce_mode,
338 idx->sha1);
d1f2d7e8
LT
339 return;
340 }
341
342 /*
343 * Something added to the tree?
344 */
345 if (!tree) {
ff7e6aad 346 show_new_file(revs, idx, cached, match_missing);
d1f2d7e8
LT
347 return;
348 }
349
350 /*
351 * Something removed from the tree?
5c21ac0e 352 */
d1f2d7e8
LT
353 if (!idx) {
354 diff_index_show_file(revs, "-", tree, tree->sha1, tree->ce_mode);
355 return;
356 }
357
358 /* Show difference between old and new */
ff7e6aad 359 show_modified(revs, tree, idx, 1, cached, match_missing);
d1f2d7e8
LT
360}
361
d1f2d7e8
LT
362/*
363 * The unpack_trees() interface is designed for merging, so
364 * the different source entries are designed primarily for
365 * the source trees, with the old index being really mainly
366 * used for being replaced by the result.
367 *
368 * For diffing, the index is more important, and we only have a
369 * single tree.
370 *
da8ba5e7 371 * We're supposed to advance o->pos to skip what we have already processed.
d1f2d7e8
LT
372 *
373 * This wrapper makes it all more readable, and takes care of all
374 * the fairly complex unpack_trees() semantic requirements, including
375 * the skipping, the path matching, the type conflict cases etc.
376 */
34110cd4 377static int oneway_diff(struct cache_entry **src, struct unpack_trees_options *o)
d1f2d7e8 378{
d1f2d7e8
LT
379 struct cache_entry *idx = src[0];
380 struct cache_entry *tree = src[1];
ff7e6aad 381 struct rev_info *revs = o->unpack_data;
d1f2d7e8 382
d1f2d7e8
LT
383 /*
384 * Unpack-trees generates a DF/conflict entry if
385 * there was a directory in the index and a tree
386 * in the tree. From a diff standpoint, that's a
387 * delete of the tree and a create of the file.
388 */
389 if (tree == o->df_conflict_entry)
390 tree = NULL;
391
392 if (ce_path_match(idx ? idx : tree, revs->prune_data))
34110cd4 393 do_oneway_diff(o, idx, tree);
d1f2d7e8 394
34110cd4 395 return 0;
d1f2d7e8
LT
396}
397
398int run_diff_index(struct rev_info *revs, int cached)
399{
400 struct object *ent;
401 struct tree *tree;
402 const char *tree_name;
403 struct unpack_trees_options opts;
404 struct tree_desc t;
e09ad6e1 405
1f1e895f
LT
406 ent = revs->pending.objects[0].item;
407 tree_name = revs->pending.objects[0].name;
e09ad6e1
JH
408 tree = parse_tree_indirect(ent->sha1);
409 if (!tree)
410 return error("bad tree object %s", tree_name);
d1f2d7e8
LT
411
412 memset(&opts, 0, sizeof(opts));
413 opts.head_idx = 1;
414 opts.index_only = cached;
a0919ced
JH
415 opts.diff_index_cached = (cached &&
416 !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER));
d1f2d7e8
LT
417 opts.merge = 1;
418 opts.fn = oneway_diff;
ff7e6aad 419 opts.unpack_data = revs;
34110cd4
LT
420 opts.src_index = &the_index;
421 opts.dst_index = NULL;
d1f2d7e8
LT
422
423 init_tree_desc(&t, tree->buffer, tree->size);
203a2fe1
DB
424 if (unpack_trees(1, &t, &opts))
425 exit(128);
d1f2d7e8 426
a5a818ee 427 diff_set_mnemonic_prefix(&revs->diffopt, "c/", cached ? "i/" : "w/");
e09ad6e1
JH
428 diffcore_std(&revs->diffopt);
429 diff_flush(&revs->diffopt);
d1f2d7e8 430 return 0;
e09ad6e1 431}
1cfe7733
JH
432
433int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
434{
435 struct tree *tree;
436 struct rev_info revs;
437 int i;
438 struct cache_entry **dst;
439 struct cache_entry *last = NULL;
204ce979
JS
440 struct unpack_trees_options opts;
441 struct tree_desc t;
1cfe7733
JH
442
443 /*
444 * This is used by git-blame to run diff-cache internally;
445 * it potentially needs to repeatedly run this, so we will
446 * start by removing the higher order entries the last round
447 * left behind.
448 */
449 dst = active_cache;
450 for (i = 0; i < active_nr; i++) {
451 struct cache_entry *ce = active_cache[i];
452 if (ce_stage(ce)) {
453 if (last && !strcmp(ce->name, last->name))
454 continue;
455 cache_tree_invalidate_path(active_cache_tree,
456 ce->name);
457 last = ce;
7a51ed66 458 ce->ce_flags |= CE_REMOVE;
1cfe7733
JH
459 }
460 *dst++ = ce;
461 }
462 active_nr = dst - active_cache;
463
464 init_revisions(&revs, NULL);
465 revs.prune_data = opt->paths;
466 tree = parse_tree_indirect(tree_sha1);
467 if (!tree)
468 die("bad tree object %s", sha1_to_hex(tree_sha1));
204ce979
JS
469
470 memset(&opts, 0, sizeof(opts));
471 opts.head_idx = 1;
472 opts.index_only = 1;
a0919ced 473 opts.diff_index_cached = !DIFF_OPT_TST(opt, FIND_COPIES_HARDER);
204ce979
JS
474 opts.merge = 1;
475 opts.fn = oneway_diff;
ff7e6aad 476 opts.unpack_data = &revs;
34110cd4
LT
477 opts.src_index = &the_index;
478 opts.dst_index = &the_index;
204ce979
JS
479
480 init_tree_desc(&t, tree->buffer, tree->size);
203a2fe1
DB
481 if (unpack_trees(1, &t, &opts))
482 exit(128);
204ce979 483 return 0;
1cfe7733 484}
75f3ff2e
SB
485
486int index_differs_from(const char *def, int diff_flags)
487{
488 struct rev_info rev;
489
490 init_revisions(&rev, NULL);
491 setup_revisions(0, NULL, &rev, def);
492 DIFF_OPT_SET(&rev.diffopt, QUIET);
493 DIFF_OPT_SET(&rev.diffopt, EXIT_WITH_STATUS);
494 rev.diffopt.flags |= diff_flags;
495 run_diff_index(&rev, 1);
496 if (rev.pending.alloc)
497 free(rev.pending.objects);
498 return (DIFF_OPT_TST(&rev.diffopt, HAS_CHANGES) != 0);
499}