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Commit | Line | Data |
---|---|---|
8bc9a0c7 LT |
1 | /* |
2 | * GIT - The information manager from hell | |
3 | * | |
4 | * Copyright (C) Linus Torvalds, 2005 | |
5 | */ | |
4d3fe0c5 JH |
6 | #define DBRT_DEBUG 1 |
7 | ||
e83c5163 LT |
8 | #include "cache.h" |
9 | ||
ee6566e8 DB |
10 | #include "object.h" |
11 | #include "tree.h" | |
744633cb JH |
12 | #include <sys/time.h> |
13 | #include <signal.h> | |
ee6566e8 DB |
14 | |
15 | static int merge = 0; | |
220a0b52 | 16 | static int update = 0; |
720d150c | 17 | static int index_only = 0; |
23822a35 LT |
18 | static int nontrivial_merge = 0; |
19 | static int trivial_merges_only = 0; | |
1b1fdf8c | 20 | static int aggressive = 0; |
744633cb JH |
21 | static int verbose_update = 0; |
22 | static volatile int progress_update = 0; | |
d99082e0 | 23 | |
ee6566e8 DB |
24 | static int head_idx = -1; |
25 | static int merge_size = 0; | |
b12ec373 | 26 | |
ee6566e8 DB |
27 | static struct object_list *trees = NULL; |
28 | ||
29 | static struct cache_entry df_conflict_entry = { | |
30 | }; | |
31 | ||
32 | static struct tree_entry_list df_conflict_list = { | |
33 | .name = NULL, | |
34 | .next = &df_conflict_list | |
35 | }; | |
36 | ||
37 | typedef int (*merge_fn_t)(struct cache_entry **src); | |
38 | ||
39 | static int entcmp(char *name1, int dir1, char *name2, int dir2) | |
40 | { | |
41 | int len1 = strlen(name1); | |
42 | int len2 = strlen(name2); | |
43 | int len = len1 < len2 ? len1 : len2; | |
44 | int ret = memcmp(name1, name2, len); | |
45 | unsigned char c1, c2; | |
46 | if (ret) | |
47 | return ret; | |
48 | c1 = name1[len]; | |
49 | c2 = name2[len]; | |
50 | if (!c1 && dir1) | |
51 | c1 = '/'; | |
52 | if (!c2 && dir2) | |
53 | c2 = '/'; | |
54 | ret = (c1 < c2) ? -1 : (c1 > c2) ? 1 : 0; | |
55 | if (c1 && c2 && !ret) | |
56 | ret = len1 - len2; | |
14242464 | 57 | return ret; |
b12ec373 JH |
58 | } |
59 | ||
ee6566e8 DB |
60 | static int unpack_trees_rec(struct tree_entry_list **posns, int len, |
61 | const char *base, merge_fn_t fn, int *indpos) | |
ca016f0e | 62 | { |
ee6566e8 DB |
63 | int baselen = strlen(base); |
64 | int src_size = len + 1; | |
65 | do { | |
66 | int i; | |
67 | char *first; | |
68 | int firstdir = 0; | |
69 | int pathlen; | |
70 | unsigned ce_size; | |
71 | struct tree_entry_list **subposns; | |
72 | struct cache_entry **src; | |
73 | int any_files = 0; | |
74 | int any_dirs = 0; | |
75 | char *cache_name; | |
76 | int ce_stage; | |
77 | ||
78 | /* Find the first name in the input. */ | |
79 | ||
80 | first = NULL; | |
81 | cache_name = NULL; | |
82 | ||
83 | /* Check the cache */ | |
84 | if (merge && *indpos < active_nr) { | |
85 | /* This is a bit tricky: */ | |
86 | /* If the index has a subdirectory (with | |
87 | * contents) as the first name, it'll get a | |
88 | * filename like "foo/bar". But that's after | |
89 | * "foo", so the entry in trees will get | |
90 | * handled first, at which point we'll go into | |
91 | * "foo", and deal with "bar" from the index, | |
92 | * because the base will be "foo/". The only | |
93 | * way we can actually have "foo/bar" first of | |
94 | * all the things is if the trees don't | |
95 | * contain "foo" at all, in which case we'll | |
96 | * handle "foo/bar" without going into the | |
97 | * directory, but that's fine (and will return | |
98 | * an error anyway, with the added unknown | |
99 | * file case. | |
100 | */ | |
101 | ||
102 | cache_name = active_cache[*indpos]->name; | |
103 | if (strlen(cache_name) > baselen && | |
104 | !memcmp(cache_name, base, baselen)) { | |
105 | cache_name += baselen; | |
106 | first = cache_name; | |
107 | } else { | |
108 | cache_name = NULL; | |
109 | } | |
110 | } | |
111 | ||
4d3fe0c5 | 112 | #if DBRT_DEBUG > 1 |
ee6566e8 DB |
113 | if (first) |
114 | printf("index %s\n", first); | |
2ab706a3 | 115 | #endif |
ee6566e8 DB |
116 | for (i = 0; i < len; i++) { |
117 | if (!posns[i] || posns[i] == &df_conflict_list) | |
118 | continue; | |
4d3fe0c5 | 119 | #if DBRT_DEBUG > 1 |
ee6566e8 | 120 | printf("%d %s\n", i + 1, posns[i]->name); |
2ab706a3 | 121 | #endif |
ee6566e8 DB |
122 | if (!first || entcmp(first, firstdir, |
123 | posns[i]->name, | |
124 | posns[i]->directory) > 0) { | |
125 | first = posns[i]->name; | |
126 | firstdir = posns[i]->directory; | |
127 | } | |
128 | } | |
129 | /* No name means we're done */ | |
130 | if (!first) | |
131 | return 0; | |
132 | ||
133 | pathlen = strlen(first); | |
134 | ce_size = cache_entry_size(baselen + pathlen); | |
135 | ||
136 | src = xmalloc(sizeof(struct cache_entry *) * src_size); | |
137 | memset(src, 0, sizeof(struct cache_entry *) * src_size); | |
138 | ||
139 | subposns = xmalloc(sizeof(struct tree_list_entry *) * len); | |
140 | memset(subposns, 0, sizeof(struct tree_list_entry *) * len); | |
141 | ||
142 | if (cache_name && !strcmp(cache_name, first)) { | |
143 | any_files = 1; | |
144 | src[0] = active_cache[*indpos]; | |
145 | remove_cache_entry_at(*indpos); | |
146 | } | |
147 | ||
148 | for (i = 0; i < len; i++) { | |
149 | struct cache_entry *ce; | |
150 | ||
151 | if (!posns[i] || | |
152 | (posns[i] != &df_conflict_list && | |
153 | strcmp(first, posns[i]->name))) { | |
154 | continue; | |
155 | } | |
156 | ||
157 | if (posns[i] == &df_conflict_list) { | |
158 | src[i + merge] = &df_conflict_entry; | |
159 | continue; | |
160 | } | |
161 | ||
162 | if (posns[i]->directory) { | |
163 | any_dirs = 1; | |
164 | parse_tree(posns[i]->item.tree); | |
165 | subposns[i] = posns[i]->item.tree->entries; | |
166 | posns[i] = posns[i]->next; | |
167 | src[i + merge] = &df_conflict_entry; | |
168 | continue; | |
169 | } | |
170 | ||
171 | if (!merge) | |
172 | ce_stage = 0; | |
173 | else if (i + 1 < head_idx) | |
174 | ce_stage = 1; | |
175 | else if (i + 1 > head_idx) | |
176 | ce_stage = 3; | |
177 | else | |
178 | ce_stage = 2; | |
179 | ||
180 | ce = xmalloc(ce_size); | |
181 | memset(ce, 0, ce_size); | |
182 | ce->ce_mode = create_ce_mode(posns[i]->mode); | |
183 | ce->ce_flags = create_ce_flags(baselen + pathlen, | |
184 | ce_stage); | |
185 | memcpy(ce->name, base, baselen); | |
186 | memcpy(ce->name + baselen, first, pathlen + 1); | |
187 | ||
188 | any_files = 1; | |
189 | ||
190 | memcpy(ce->sha1, posns[i]->item.any->sha1, 20); | |
191 | src[i + merge] = ce; | |
192 | subposns[i] = &df_conflict_list; | |
193 | posns[i] = posns[i]->next; | |
194 | } | |
195 | if (any_files) { | |
196 | if (merge) { | |
197 | int ret; | |
198 | ||
4d3fe0c5 | 199 | #if DBRT_DEBUG > 1 |
ee6566e8 DB |
200 | printf("%s:\n", first); |
201 | for (i = 0; i < src_size; i++) { | |
202 | printf(" %d ", i); | |
203 | if (src[i]) | |
204 | printf("%s\n", sha1_to_hex(src[i]->sha1)); | |
205 | else | |
206 | printf("\n"); | |
207 | } | |
2ab706a3 | 208 | #endif |
ee6566e8 DB |
209 | ret = fn(src); |
210 | ||
4d3fe0c5 | 211 | #if DBRT_DEBUG > 1 |
ee6566e8 | 212 | printf("Added %d entries\n", ret); |
2ab706a3 | 213 | #endif |
ee6566e8 DB |
214 | *indpos += ret; |
215 | } else { | |
216 | for (i = 0; i < src_size; i++) { | |
217 | if (src[i]) { | |
218 | add_cache_entry(src[i], ADD_CACHE_OK_TO_ADD|ADD_CACHE_SKIP_DFCHECK); | |
219 | } | |
220 | } | |
221 | } | |
222 | } | |
223 | if (any_dirs) { | |
224 | char *newbase = xmalloc(baselen + 2 + pathlen); | |
225 | memcpy(newbase, base, baselen); | |
226 | memcpy(newbase + baselen, first, pathlen); | |
227 | newbase[baselen + pathlen] = '/'; | |
228 | newbase[baselen + pathlen + 1] = '\0'; | |
229 | if (unpack_trees_rec(subposns, len, newbase, fn, | |
230 | indpos)) | |
231 | return -1; | |
bb97a2a8 | 232 | free(newbase); |
ee6566e8 DB |
233 | } |
234 | free(subposns); | |
235 | free(src); | |
236 | } while (1); | |
ca016f0e LT |
237 | } |
238 | ||
ee6566e8 | 239 | static void reject_merge(struct cache_entry *ce) |
43f91266 | 240 | { |
ee6566e8 DB |
241 | die("Entry '%s' would be overwritten by merge. Cannot merge.", |
242 | ce->name); | |
43f91266 LT |
243 | } |
244 | ||
340e4f88 JH |
245 | /* Unlink the last component and attempt to remove leading |
246 | * directories, in case this unlink is the removal of the | |
247 | * last entry in the directory -- empty directories are removed. | |
248 | */ | |
249 | static void unlink_entry(char *name) | |
250 | { | |
251 | char *cp, *prev; | |
252 | ||
253 | if (unlink(name)) | |
254 | return; | |
255 | prev = NULL; | |
256 | while (1) { | |
257 | int status; | |
258 | cp = strrchr(name, '/'); | |
259 | if (prev) | |
260 | *prev = '/'; | |
261 | if (!cp) | |
262 | break; | |
263 | ||
264 | *cp = 0; | |
265 | status = rmdir(name); | |
266 | if (status) { | |
267 | *cp = '/'; | |
268 | break; | |
269 | } | |
270 | prev = cp; | |
271 | } | |
272 | } | |
273 | ||
744633cb JH |
274 | static void progress_interval(int signum) |
275 | { | |
276 | signal(SIGALRM, progress_interval); | |
277 | progress_update = 1; | |
278 | } | |
279 | ||
ee6566e8 DB |
280 | static void check_updates(struct cache_entry **src, int nr) |
281 | { | |
282 | static struct checkout state = { | |
283 | .base_dir = "", | |
284 | .force = 1, | |
285 | .quiet = 1, | |
286 | .refresh_cache = 1, | |
287 | }; | |
288 | unsigned short mask = htons(CE_UPDATE); | |
744633cb JH |
289 | unsigned last_percent = 200, cnt = 0, total = 0; |
290 | ||
291 | if (update && verbose_update) { | |
292 | struct itimerval v; | |
293 | ||
294 | for (total = cnt = 0; cnt < nr; cnt++) { | |
295 | struct cache_entry *ce = src[cnt]; | |
296 | if (!ce->ce_mode || ce->ce_flags & mask) | |
297 | total++; | |
298 | } | |
299 | ||
300 | /* Don't bother doing this for very small updates */ | |
301 | if (total < 250) | |
302 | total = 0; | |
303 | ||
304 | if (total) { | |
305 | v.it_interval.tv_sec = 1; | |
306 | v.it_interval.tv_usec = 0; | |
307 | v.it_value = v.it_interval; | |
308 | signal(SIGALRM, progress_interval); | |
309 | setitimer(ITIMER_REAL, &v, NULL); | |
310 | fprintf(stderr, "Checking files out...\n"); | |
311 | progress_update = 1; | |
312 | } | |
313 | cnt = 0; | |
314 | } | |
315 | ||
ee6566e8 DB |
316 | while (nr--) { |
317 | struct cache_entry *ce = *src++; | |
744633cb JH |
318 | |
319 | if (total) { | |
320 | if (!ce->ce_mode || ce->ce_flags & mask) { | |
321 | unsigned percent; | |
322 | cnt++; | |
323 | percent = (cnt * 100) / total; | |
324 | if (percent != last_percent || | |
325 | progress_update) { | |
326 | fprintf(stderr, "%4u%% (%u/%u) done\r", | |
327 | percent, cnt, total); | |
328 | last_percent = percent; | |
329 | } | |
330 | } | |
331 | } | |
ee6566e8 DB |
332 | if (!ce->ce_mode) { |
333 | if (update) | |
340e4f88 | 334 | unlink_entry(ce->name); |
ee6566e8 DB |
335 | continue; |
336 | } | |
337 | if (ce->ce_flags & mask) { | |
338 | ce->ce_flags &= ~mask; | |
339 | if (update) | |
340 | checkout_entry(ce, &state); | |
341 | } | |
342 | } | |
744633cb JH |
343 | if (total) { |
344 | fputc('\n', stderr); | |
345 | signal(SIGALRM, SIG_IGN); | |
346 | } | |
ee6566e8 | 347 | } |
43f91266 | 348 | |
ee6566e8 | 349 | static int unpack_trees(merge_fn_t fn) |
d99082e0 | 350 | { |
ee6566e8 DB |
351 | int indpos = 0; |
352 | unsigned len = object_list_length(trees); | |
7e4a2a84 | 353 | struct tree_entry_list **posns; |
ee6566e8 DB |
354 | int i; |
355 | struct object_list *posn = trees; | |
356 | merge_size = len; | |
7e4a2a84 JH |
357 | |
358 | if (len) { | |
359 | posns = xmalloc(len * sizeof(struct tree_entry_list *)); | |
360 | for (i = 0; i < len; i++) { | |
361 | posns[i] = ((struct tree *) posn->item)->entries; | |
362 | posn = posn->next; | |
363 | } | |
364 | if (unpack_trees_rec(posns, len, "", fn, &indpos)) | |
365 | return -1; | |
d723c690 | 366 | } |
ee6566e8 | 367 | |
23822a35 LT |
368 | if (trivial_merges_only && nontrivial_merge) |
369 | die("Merge requires file-level merging"); | |
370 | ||
ee6566e8 DB |
371 | check_updates(active_cache, active_nr); |
372 | return 0; | |
d99082e0 LT |
373 | } |
374 | ||
ee6566e8 DB |
375 | static int list_tree(unsigned char *sha1) |
376 | { | |
377 | struct tree *tree = parse_tree_indirect(sha1); | |
378 | if (!tree) | |
379 | return -1; | |
380 | object_list_append(&tree->object, &trees); | |
381 | return 0; | |
382 | } | |
383 | ||
384 | static int same(struct cache_entry *a, struct cache_entry *b) | |
385 | { | |
386 | if (!!a != !!b) | |
387 | return 0; | |
388 | if (!a && !b) | |
389 | return 1; | |
390 | return a->ce_mode == b->ce_mode && | |
391 | !memcmp(a->sha1, b->sha1, 20); | |
392 | } | |
393 | ||
394 | ||
02ede67a LT |
395 | /* |
396 | * When a CE gets turned into an unmerged entry, we | |
397 | * want it to be up-to-date | |
398 | */ | |
399 | static void verify_uptodate(struct cache_entry *ce) | |
400 | { | |
401 | struct stat st; | |
402 | ||
720d150c JH |
403 | if (index_only) |
404 | return; | |
405 | ||
02ede67a LT |
406 | if (!lstat(ce->name, &st)) { |
407 | unsigned changed = ce_match_stat(ce, &st); | |
408 | if (!changed) | |
409 | return; | |
410 | errno = 0; | |
411 | } | |
412 | if (errno == ENOENT) | |
413 | return; | |
414 | die("Entry '%s' not uptodate. Cannot merge.", ce->name); | |
415 | } | |
416 | ||
ee6566e8 | 417 | static int merged_entry(struct cache_entry *merge, struct cache_entry *old) |
d99082e0 | 418 | { |
d723c690 LT |
419 | merge->ce_flags |= htons(CE_UPDATE); |
420 | if (old) { | |
02ede67a | 421 | /* |
d723c690 LT |
422 | * See if we can re-use the old CE directly? |
423 | * That way we get the uptodate stat info. | |
424 | * | |
425 | * This also removes the UPDATE flag on | |
426 | * a match. | |
02ede67a | 427 | */ |
d723c690 LT |
428 | if (same(old, merge)) { |
429 | *merge = *old; | |
ee6566e8 | 430 | } else { |
d723c690 LT |
431 | verify_uptodate(old); |
432 | } | |
a3a65234 | 433 | } |
d723c690 | 434 | merge->ce_flags &= ~htons(CE_STAGEMASK); |
ee6566e8 | 435 | add_cache_entry(merge, ADD_CACHE_OK_TO_ADD); |
d723c690 | 436 | return 1; |
a3a65234 LT |
437 | } |
438 | ||
ee6566e8 | 439 | static int deleted_entry(struct cache_entry *ce, struct cache_entry *old) |
aa16021e LT |
440 | { |
441 | if (old) | |
442 | verify_uptodate(old); | |
443 | ce->ce_mode = 0; | |
ee6566e8 | 444 | add_cache_entry(ce, ADD_CACHE_OK_TO_ADD); |
aa16021e LT |
445 | return 1; |
446 | } | |
447 | ||
ee6566e8 | 448 | static int keep_entry(struct cache_entry *ce) |
32192e66 | 449 | { |
ee6566e8 DB |
450 | add_cache_entry(ce, ADD_CACHE_OK_TO_ADD); |
451 | return 1; | |
32192e66 JH |
452 | } |
453 | ||
4d3fe0c5 JH |
454 | #if DBRT_DEBUG |
455 | static void show_stage_entry(FILE *o, | |
456 | const char *label, const struct cache_entry *ce) | |
457 | { | |
2ba6c47b JH |
458 | if (!ce) |
459 | fprintf(o, "%s (missing)\n", label); | |
460 | else | |
461 | fprintf(o, "%s%06o %s %d\t%s\n", | |
462 | label, | |
463 | ntohl(ce->ce_mode), | |
464 | sha1_to_hex(ce->sha1), | |
465 | ce_stage(ce), | |
466 | ce->name); | |
4d3fe0c5 JH |
467 | } |
468 | #endif | |
469 | ||
ee6566e8 | 470 | static int threeway_merge(struct cache_entry **stages) |
e6ee623b | 471 | { |
ee6566e8 DB |
472 | struct cache_entry *index; |
473 | struct cache_entry *head; | |
474 | struct cache_entry *remote = stages[head_idx + 1]; | |
d723c690 | 475 | int count; |
ee6566e8 DB |
476 | int head_match = 0; |
477 | int remote_match = 0; | |
d723c690 | 478 | |
ee6566e8 DB |
479 | int df_conflict_head = 0; |
480 | int df_conflict_remote = 0; | |
481 | ||
482 | int any_anc_missing = 0; | |
1b1fdf8c | 483 | int no_anc_exists = 1; |
ee6566e8 DB |
484 | int i; |
485 | ||
486 | for (i = 1; i < head_idx; i++) { | |
487 | if (!stages[i]) | |
488 | any_anc_missing = 1; | |
1b1fdf8c JH |
489 | else |
490 | no_anc_exists = 0; | |
e7f9bc41 | 491 | } |
ee6566e8 DB |
492 | |
493 | index = stages[0]; | |
494 | head = stages[head_idx]; | |
495 | ||
496 | if (head == &df_conflict_entry) { | |
497 | df_conflict_head = 1; | |
498 | head = NULL; | |
499 | } | |
500 | ||
501 | if (remote == &df_conflict_entry) { | |
502 | df_conflict_remote = 1; | |
503 | remote = NULL; | |
504 | } | |
505 | ||
506 | /* First, if there's a #16 situation, note that to prevent #13 | |
507 | * and #14. | |
508 | */ | |
509 | if (!same(remote, head)) { | |
510 | for (i = 1; i < head_idx; i++) { | |
511 | if (same(stages[i], head)) { | |
4d3fe0c5 | 512 | head_match = i; |
ee6566e8 DB |
513 | } |
514 | if (same(stages[i], remote)) { | |
4d3fe0c5 | 515 | remote_match = i; |
ee6566e8 | 516 | } |
32192e66 | 517 | } |
32192e66 | 518 | } |
ee6566e8 DB |
519 | |
520 | /* We start with cases where the index is allowed to match | |
521 | * something other than the head: #14(ALT) and #2ALT, where it | |
522 | * is permitted to match the result instead. | |
523 | */ | |
524 | /* #14, #14ALT, #2ALT */ | |
525 | if (remote && !df_conflict_head && head_match && !remote_match) { | |
526 | if (index && !same(index, remote) && !same(index, head)) | |
527 | reject_merge(index); | |
528 | return merged_entry(remote, index); | |
036d51cc | 529 | } |
d723c690 | 530 | /* |
ee6566e8 DB |
531 | * If we have an entry in the index cache, then we want to |
532 | * make sure that it matches head. | |
d723c690 | 533 | */ |
ee6566e8 DB |
534 | if (index && !same(index, head)) { |
535 | reject_merge(index); | |
e6ee623b | 536 | } |
ee6566e8 DB |
537 | |
538 | if (head) { | |
539 | /* #5ALT, #15 */ | |
540 | if (same(head, remote)) | |
541 | return merged_entry(head, index); | |
542 | /* #13, #3ALT */ | |
543 | if (!df_conflict_remote && remote_match && !head_match) | |
544 | return merged_entry(head, index); | |
545 | } | |
546 | ||
547 | /* #1 */ | |
548 | if (!head && !remote && any_anc_missing) | |
549 | return 0; | |
550 | ||
1b1fdf8c JH |
551 | /* Under the new "aggressive" rule, we resolve mostly trivial |
552 | * cases that we historically had git-merge-one-file resolve. | |
553 | */ | |
554 | if (aggressive) { | |
555 | int head_deleted = !head && !df_conflict_head; | |
556 | int remote_deleted = !remote && !df_conflict_remote; | |
557 | /* | |
558 | * Deleted in both. | |
559 | * Deleted in one and unchanged in the other. | |
560 | */ | |
561 | if ((head_deleted && remote_deleted) || | |
562 | (head_deleted && remote && remote_match) || | |
11420380 JH |
563 | (remote_deleted && head && head_match)) { |
564 | if (index) | |
565 | return deleted_entry(index, index); | |
1b1fdf8c | 566 | return 0; |
11420380 | 567 | } |
1b1fdf8c JH |
568 | /* |
569 | * Added in both, identically. | |
570 | */ | |
571 | if (no_anc_exists && head && remote && same(head, remote)) | |
572 | return merged_entry(head, index); | |
573 | ||
574 | } | |
575 | ||
ee6566e8 DB |
576 | /* Below are "no merge" cases, which require that the index be |
577 | * up-to-date to avoid the files getting overwritten with | |
578 | * conflict resolution files. | |
579 | */ | |
580 | if (index) { | |
581 | verify_uptodate(index); | |
582 | } | |
583 | ||
23822a35 LT |
584 | nontrivial_merge = 1; |
585 | ||
ee6566e8 | 586 | /* #2, #3, #4, #6, #7, #9, #11. */ |
d723c690 | 587 | count = 0; |
ee6566e8 DB |
588 | if (!head_match || !remote_match) { |
589 | for (i = 1; i < head_idx; i++) { | |
590 | if (stages[i]) { | |
591 | keep_entry(stages[i]); | |
592 | count++; | |
593 | break; | |
594 | } | |
595 | } | |
596 | } | |
4d3fe0c5 JH |
597 | #if DBRT_DEBUG |
598 | else { | |
599 | fprintf(stderr, "read-tree: warning #16 detected\n"); | |
600 | show_stage_entry(stderr, "head ", stages[head_match]); | |
601 | show_stage_entry(stderr, "remote ", stages[remote_match]); | |
602 | } | |
603 | #endif | |
ee6566e8 DB |
604 | if (head) { count += keep_entry(head); } |
605 | if (remote) { count += keep_entry(remote); } | |
d723c690 | 606 | return count; |
e6ee623b LT |
607 | } |
608 | ||
220a0b52 LT |
609 | /* |
610 | * Two-way merge. | |
611 | * | |
c8596009 JH |
612 | * The rule is to "carry forward" what is in the index without losing |
613 | * information across a "fast forward", favoring a successful merge | |
614 | * over a merge failure when it makes sense. For details of the | |
615 | * "carry forward" rule, please see <Documentation/git-read-tree.txt>. | |
616 | * | |
220a0b52 | 617 | */ |
ee6566e8 | 618 | static int twoway_merge(struct cache_entry **src) |
a3a65234 | 619 | { |
c8596009 JH |
620 | struct cache_entry *current = src[0]; |
621 | struct cache_entry *oldtree = src[1], *newtree = src[2]; | |
220a0b52 | 622 | |
ee6566e8 | 623 | if (merge_size != 2) |
bd2afde8 | 624 | return error("Cannot do a twoway merge of %d trees", |
ee6566e8 | 625 | merge_size); |
e6ee623b | 626 | |
c8596009 JH |
627 | if (current) { |
628 | if ((!oldtree && !newtree) || /* 4 and 5 */ | |
629 | (!oldtree && newtree && | |
630 | same(current, newtree)) || /* 6 and 7 */ | |
631 | (oldtree && newtree && | |
632 | same(oldtree, newtree)) || /* 14 and 15 */ | |
633 | (oldtree && newtree && | |
634 | !same(oldtree, newtree) && /* 18 and 19*/ | |
635 | same(current, newtree))) { | |
ee6566e8 | 636 | return keep_entry(current); |
c8596009 JH |
637 | } |
638 | else if (oldtree && !newtree && same(current, oldtree)) { | |
639 | /* 10 or 11 */ | |
ee6566e8 | 640 | return deleted_entry(oldtree, current); |
c8596009 JH |
641 | } |
642 | else if (oldtree && newtree && | |
643 | same(current, oldtree) && !same(current, newtree)) { | |
644 | /* 20 or 21 */ | |
ee6566e8 | 645 | return merged_entry(newtree, current); |
c8596009 | 646 | } |
ee6566e8 | 647 | else { |
c8596009 | 648 | /* all other failures */ |
ee6566e8 DB |
649 | if (oldtree) |
650 | reject_merge(oldtree); | |
651 | if (current) | |
652 | reject_merge(current); | |
653 | if (newtree) | |
654 | reject_merge(newtree); | |
d723c690 | 655 | return -1; |
ee6566e8 | 656 | } |
e6ee623b | 657 | } |
c8596009 | 658 | else if (newtree) |
ee6566e8 | 659 | return merged_entry(newtree, current); |
c8596009 | 660 | else |
ee6566e8 | 661 | return deleted_entry(oldtree, current); |
03efa6d9 JH |
662 | } |
663 | ||
d723c690 LT |
664 | /* |
665 | * One-way merge. | |
666 | * | |
667 | * The rule is: | |
668 | * - take the stat information from stage0, take the data from stage1 | |
669 | */ | |
ee6566e8 | 670 | static int oneway_merge(struct cache_entry **src) |
220a0b52 | 671 | { |
d723c690 LT |
672 | struct cache_entry *old = src[0]; |
673 | struct cache_entry *a = src[1]; | |
a3a65234 | 674 | |
ee6566e8 | 675 | if (merge_size != 1) |
bd2afde8 | 676 | return error("Cannot do a oneway merge of %d trees", |
ee6566e8 | 677 | merge_size); |
a3a65234 | 678 | |
d723c690 LT |
679 | if (!a) |
680 | return 0; | |
b5b42507 | 681 | if (old && same(old, a)) { |
ee6566e8 | 682 | return keep_entry(old); |
b5b42507 | 683 | } |
ee6566e8 | 684 | return merged_entry(a, NULL); |
d723c690 LT |
685 | } |
686 | ||
438195cc LT |
687 | static int read_cache_unmerged(void) |
688 | { | |
689 | int i, deleted; | |
690 | struct cache_entry **dst; | |
691 | ||
692 | read_cache(); | |
693 | dst = active_cache; | |
694 | deleted = 0; | |
695 | for (i = 0; i < active_nr; i++) { | |
696 | struct cache_entry *ce = active_cache[i]; | |
697 | if (ce_stage(ce)) { | |
698 | deleted++; | |
699 | continue; | |
700 | } | |
701 | if (deleted) | |
702 | *dst = ce; | |
703 | dst++; | |
704 | } | |
705 | active_nr -= deleted; | |
706 | return deleted; | |
707 | } | |
708 | ||
720d150c | 709 | static const char read_tree_usage[] = "git-read-tree (<sha> | -m [-u | -i] <sha1> [<sha2> [<sha3>]])"; |
c5bac17a | 710 | |
96cd5429 JH |
711 | static struct cache_file cache_file; |
712 | ||
e83c5163 LT |
713 | int main(int argc, char **argv) |
714 | { | |
ee6566e8 | 715 | int i, newfd, reset, stage = 0; |
e83c5163 | 716 | unsigned char sha1[20]; |
ee6566e8 | 717 | merge_fn_t fn = NULL; |
bb233d69 | 718 | |
53228a5f JH |
719 | setup_git_directory(); |
720 | ||
96cd5429 | 721 | newfd = hold_index_file_for_update(&cache_file, get_index_file()); |
83adac3c | 722 | if (newfd < 0) |
2de381f9 | 723 | die("unable to create new cachefile"); |
83adac3c | 724 | |
39b4ac99 AR |
725 | git_config(git_default_config); |
726 | ||
ca016f0e | 727 | merge = 0; |
438195cc | 728 | reset = 0; |
83adac3c LT |
729 | for (i = 1; i < argc; i++) { |
730 | const char *arg = argv[i]; | |
731 | ||
720d150c JH |
732 | /* "-u" means "update", meaning that a merge will update |
733 | * the working tree. | |
734 | */ | |
220a0b52 LT |
735 | if (!strcmp(arg, "-u")) { |
736 | update = 1; | |
737 | continue; | |
738 | } | |
739 | ||
744633cb JH |
740 | if (!strcmp(arg, "-v")) { |
741 | verbose_update = 1; | |
742 | continue; | |
743 | } | |
744 | ||
720d150c JH |
745 | /* "-i" means "index only", meaning that a merge will |
746 | * not even look at the working tree. | |
747 | */ | |
748 | if (!strcmp(arg, "-i")) { | |
749 | index_only = 1; | |
750 | continue; | |
751 | } | |
752 | ||
438195cc LT |
753 | /* This differs from "-m" in that we'll silently ignore unmerged entries */ |
754 | if (!strcmp(arg, "--reset")) { | |
ee6566e8 | 755 | if (stage || merge) |
438195cc LT |
756 | usage(read_tree_usage); |
757 | reset = 1; | |
758 | merge = 1; | |
759 | stage = 1; | |
760 | read_cache_unmerged(); | |
7875b50d | 761 | continue; |
438195cc LT |
762 | } |
763 | ||
23822a35 LT |
764 | if (!strcmp(arg, "--trivial")) { |
765 | trivial_merges_only = 1; | |
766 | continue; | |
767 | } | |
768 | ||
1b1fdf8c JH |
769 | if (!strcmp(arg, "--aggressive")) { |
770 | aggressive = 1; | |
771 | continue; | |
772 | } | |
773 | ||
d99082e0 | 774 | /* "-m" stands for "merge", meaning we start in stage 1 */ |
83adac3c | 775 | if (!strcmp(arg, "-m")) { |
ee6566e8 | 776 | if (stage || merge) |
438195cc LT |
777 | usage(read_tree_usage); |
778 | if (read_cache_unmerged()) | |
779 | die("you need to resolve your current index first"); | |
d99082e0 | 780 | stage = 1; |
ca016f0e | 781 | merge = 1; |
83adac3c LT |
782 | continue; |
783 | } | |
03efa6d9 | 784 | |
720d150c JH |
785 | /* using -u and -i at the same time makes no sense */ |
786 | if (1 < index_only + update) | |
787 | usage(read_tree_usage); | |
788 | ||
3c249c95 | 789 | if (get_sha1(arg, sha1) < 0) |
c5bac17a | 790 | usage(read_tree_usage); |
ee6566e8 | 791 | if (list_tree(sha1) < 0) |
2de381f9 | 792 | die("failed to unpack tree object %s", arg); |
d99082e0 | 793 | stage++; |
83adac3c | 794 | } |
f318dd22 | 795 | if ((update||index_only) && !merge) |
a57f0b58 | 796 | usage(read_tree_usage); |
7dd43575 JH |
797 | |
798 | if (merge) { | |
ee6566e8 | 799 | if (stage < 2) |
a3a65234 | 800 | die("just how do you expect me to merge %d trees?", stage-1); |
ee6566e8 DB |
801 | switch (stage - 1) { |
802 | case 1: | |
803 | fn = oneway_merge; | |
804 | break; | |
805 | case 2: | |
806 | fn = twoway_merge; | |
807 | break; | |
808 | case 3: | |
809 | fn = threeway_merge; | |
810 | break; | |
811 | default: | |
812 | fn = threeway_merge; | |
813 | break; | |
03efa6d9 | 814 | } |
ee6566e8 | 815 | |
ee6566e8 DB |
816 | if (stage - 1 >= 3) |
817 | head_idx = stage - 2; | |
818 | else | |
819 | head_idx = 1; | |
820 | } | |
821 | ||
822 | unpack_trees(fn); | |
96cd5429 JH |
823 | if (write_cache(newfd, active_cache, active_nr) || |
824 | commit_index_file(&cache_file)) | |
2de381f9 | 825 | die("unable to write new index file"); |
9614b8dc | 826 | return 0; |
e83c5163 | 827 | } |