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chromium / external / github.com / git / git / refs/tags/v0.99.7c / . / read-tree.c
blob: 6a5c08c4c6903fec45cbe37a63f0bc42fbae53bc [file] [log] [blame]
Linus Torvalds8bc9a0c2005-04-07 22:16:10[diff] [blame]1/*
2 * GIT - The information manager from hell
3 *
4 * Copyright (C) Linus Torvalds, 2005
5 */
Junio C Hamano4d3fe0c2005-09-06 19:53:56[diff] [blame]6#define DBRT_DEBUG 1
7
Linus Torvaldse83c5162005-04-07 22:13:13[diff] [blame]8#include "cache.h"
9
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]10#include "object.h"
11#include "tree.h"
12
13static int merge = 0;
Linus Torvalds220a0b52005-06-06 05:07:31[diff] [blame]14static int update = 0;
Junio C Hamano720d1502005-09-11 00:46:27[diff] [blame]15static int index_only = 0;
Linus Torvaldsd99082e2005-04-16 05:53:45[diff] [blame]16
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]17static int head_idx = -1;
18static int merge_size = 0;
Junio C Hamanob12ec372005-04-21 01:06:50[diff] [blame]19
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]20static struct object_list *trees = NULL;
21
22static struct cache_entry df_conflict_entry = {
23};
24
25static struct tree_entry_list df_conflict_list = {
26 .name = NULL,
27 .next = &df_conflict_list
28};
29
30typedef int (*merge_fn_t)(struct cache_entry **src);
31
32static int entcmp(char *name1, int dir1, char *name2, int dir2)
33{
34 int len1 = strlen(name1);
35 int len2 = strlen(name2);
36 int len = len1 < len2 ? len1 : len2;
37 int ret = memcmp(name1, name2, len);
38 unsigned char c1, c2;
39 if (ret)
40 return ret;
41 c1 = name1[len];
42 c2 = name2[len];
43 if (!c1 && dir1)
44 c1 = '/';
45 if (!c2 && dir2)
46 c2 = '/';
47 ret = (c1 < c2) ? -1 : (c1 > c2) ? 1 : 0;
48 if (c1 && c2 && !ret)
49 ret = len1 - len2;
Petr Baudis14242462005-05-11 21:16:23[diff] [blame]50 return ret;
Junio C Hamanob12ec372005-04-21 01:06:50[diff] [blame]51}
52
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]53static int unpack_trees_rec(struct tree_entry_list **posns, int len,
54 const char *base, merge_fn_t fn, int *indpos)
Linus Torvaldsca016f02005-04-19 18:16:12[diff] [blame]55{
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]56 int baselen = strlen(base);
57 int src_size = len + 1;
58 do {
59 int i;
60 char *first;
61 int firstdir = 0;
62 int pathlen;
63 unsigned ce_size;
64 struct tree_entry_list **subposns;
65 struct cache_entry **src;
66 int any_files = 0;
67 int any_dirs = 0;
68 char *cache_name;
69 int ce_stage;
70
71 /* Find the first name in the input. */
72
73 first = NULL;
74 cache_name = NULL;
75
76 /* Check the cache */
77 if (merge && *indpos < active_nr) {
78 /* This is a bit tricky: */
79 /* If the index has a subdirectory (with
80 * contents) as the first name, it'll get a
81 * filename like "foo/bar". But that's after
82 * "foo", so the entry in trees will get
83 * handled first, at which point we'll go into
84 * "foo", and deal with "bar" from the index,
85 * because the base will be "foo/". The only
86 * way we can actually have "foo/bar" first of
87 * all the things is if the trees don't
88 * contain "foo" at all, in which case we'll
89 * handle "foo/bar" without going into the
90 * directory, but that's fine (and will return
91 * an error anyway, with the added unknown
92 * file case.
93 */
94
95 cache_name = active_cache[*indpos]->name;
96 if (strlen(cache_name) > baselen &&
97 !memcmp(cache_name, base, baselen)) {
98 cache_name += baselen;
99 first = cache_name;
100 } else {
101 cache_name = NULL;
102 }
103 }
104
Junio C Hamano4d3fe0c2005-09-06 19:53:56[diff] [blame]105#if DBRT_DEBUG > 1
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]106 if (first)
107 printf("index %s\n", first);
Junio C Hamano2ab706a2005-09-05 08:13:36[diff] [blame]108#endif
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]109 for (i = 0; i < len; i++) {
110 if (!posns[i] || posns[i] == &df_conflict_list)
111 continue;
Junio C Hamano4d3fe0c2005-09-06 19:53:56[diff] [blame]112#if DBRT_DEBUG > 1
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]113 printf("%d %s\n", i + 1, posns[i]->name);
Junio C Hamano2ab706a2005-09-05 08:13:36[diff] [blame]114#endif
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]115 if (!first || entcmp(first, firstdir,
116 posns[i]->name,
117 posns[i]->directory) > 0) {
118 first = posns[i]->name;
119 firstdir = posns[i]->directory;
120 }
121 }
122 /* No name means we're done */
123 if (!first)
124 return 0;
125
126 pathlen = strlen(first);
127 ce_size = cache_entry_size(baselen + pathlen);
128
129 src = xmalloc(sizeof(struct cache_entry *) * src_size);
130 memset(src, 0, sizeof(struct cache_entry *) * src_size);
131
132 subposns = xmalloc(sizeof(struct tree_list_entry *) * len);
133 memset(subposns, 0, sizeof(struct tree_list_entry *) * len);
134
135 if (cache_name && !strcmp(cache_name, first)) {
136 any_files = 1;
137 src[0] = active_cache[*indpos];
138 remove_cache_entry_at(*indpos);
139 }
140
141 for (i = 0; i < len; i++) {
142 struct cache_entry *ce;
143
144 if (!posns[i] ||
145 (posns[i] != &df_conflict_list &&
146 strcmp(first, posns[i]->name))) {
147 continue;
148 }
149
150 if (posns[i] == &df_conflict_list) {
151 src[i + merge] = &df_conflict_entry;
152 continue;
153 }
154
155 if (posns[i]->directory) {
156 any_dirs = 1;
157 parse_tree(posns[i]->item.tree);
158 subposns[i] = posns[i]->item.tree->entries;
159 posns[i] = posns[i]->next;
160 src[i + merge] = &df_conflict_entry;
161 continue;
162 }
163
164 if (!merge)
165 ce_stage = 0;
166 else if (i + 1 < head_idx)
167 ce_stage = 1;
168 else if (i + 1 > head_idx)
169 ce_stage = 3;
170 else
171 ce_stage = 2;
172
173 ce = xmalloc(ce_size);
174 memset(ce, 0, ce_size);
175 ce->ce_mode = create_ce_mode(posns[i]->mode);
176 ce->ce_flags = create_ce_flags(baselen + pathlen,
177 ce_stage);
178 memcpy(ce->name, base, baselen);
179 memcpy(ce->name + baselen, first, pathlen + 1);
180
181 any_files = 1;
182
183 memcpy(ce->sha1, posns[i]->item.any->sha1, 20);
184 src[i + merge] = ce;
185 subposns[i] = &df_conflict_list;
186 posns[i] = posns[i]->next;
187 }
188 if (any_files) {
189 if (merge) {
190 int ret;
191
Junio C Hamano4d3fe0c2005-09-06 19:53:56[diff] [blame]192#if DBRT_DEBUG > 1
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]193 printf("%s:\n", first);
194 for (i = 0; i < src_size; i++) {
195 printf(" %d ", i);
196 if (src[i])
197 printf("%s\n", sha1_to_hex(src[i]->sha1));
198 else
199 printf("\n");
200 }
Junio C Hamano2ab706a2005-09-05 08:13:36[diff] [blame]201#endif
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]202 ret = fn(src);
203
Junio C Hamano4d3fe0c2005-09-06 19:53:56[diff] [blame]204#if DBRT_DEBUG > 1
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]205 printf("Added %d entries\n", ret);
Junio C Hamano2ab706a2005-09-05 08:13:36[diff] [blame]206#endif
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]207 *indpos += ret;
208 } else {
209 for (i = 0; i < src_size; i++) {
210 if (src[i]) {
211 add_cache_entry(src[i], ADD_CACHE_OK_TO_ADD|ADD_CACHE_SKIP_DFCHECK);
212 }
213 }
214 }
215 }
216 if (any_dirs) {
217 char *newbase = xmalloc(baselen + 2 + pathlen);
218 memcpy(newbase, base, baselen);
219 memcpy(newbase + baselen, first, pathlen);
220 newbase[baselen + pathlen] = '/';
221 newbase[baselen + pathlen + 1] = '\0';
222 if (unpack_trees_rec(subposns, len, newbase, fn,
223 indpos))
224 return -1;
Junio C Hamanobb97a2a2005-09-11 01:14:14[diff] [blame]225 free(newbase);
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]226 }
227 free(subposns);
228 free(src);
229 } while (1);
Linus Torvaldsca016f02005-04-19 18:16:12[diff] [blame]230}
231
Linus Torvalds76f38342005-06-06 03:28:33[diff] [blame]232static void reject_merge(struct cache_entry *ce)
Linus Torvalds02ede672005-06-06 03:02:31[diff] [blame]233{
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]234 die("Entry '%s' would be overwritten by merge. Cannot merge.",
235 ce->name);
Linus Torvaldsd99082e2005-04-16 05:53:45[diff] [blame]236}
237
Linus Torvalds220a0b52005-06-06 05:07:31[diff] [blame]238static void check_updates(struct cache_entry **src, int nr)
239{
240 static struct checkout state = {
241 .base_dir = "",
242 .force = 1,
243 .quiet = 1,
244 .refresh_cache = 1,
245 };
246 unsigned short mask = htons(CE_UPDATE);
247 while (nr--) {
248 struct cache_entry *ce = *src++;
Linus Torvaldsaa160212005-06-09 22:34:04[diff] [blame]249 if (!ce->ce_mode) {
250 if (update)
251 unlink(ce->name);
252 continue;
253 }
Linus Torvalds220a0b52005-06-06 05:07:31[diff] [blame]254 if (ce->ce_flags & mask) {
255 ce->ce_flags &= ~mask;
256 if (update)
257 checkout_entry(ce, &state);
258 }
259 }
260}
261
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]262static int unpack_trees(merge_fn_t fn)
Linus Torvaldsd723c692005-06-06 21:01:58[diff] [blame]263{
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]264 int indpos = 0;
265 unsigned len = object_list_length(trees);
266 struct tree_entry_list **posns =
267 xmalloc(len * sizeof(struct tree_entry_list *));
268 int i;
269 struct object_list *posn = trees;
270 merge_size = len;
271 for (i = 0; i < len; i++) {
272 posns[i] = ((struct tree *) posn->item)->entries;
273 posn = posn->next;
Linus Torvaldsd723c692005-06-06 21:01:58[diff] [blame]274 }
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]275 if (unpack_trees_rec(posns, len, "", fn, &indpos))
276 return -1;
277
Linus Torvaldsd723c692005-06-06 21:01:58[diff] [blame]278 check_updates(active_cache, active_nr);
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]279 return 0;
280}
281
282static int list_tree(unsigned char *sha1)
283{
284 struct tree *tree = parse_tree_indirect(sha1);
285 if (!tree)
286 return -1;
287 object_list_append(&tree->object, &trees);
288 return 0;
289}
290
291static int same(struct cache_entry *a, struct cache_entry *b)
292{
293 if (!!a != !!b)
294 return 0;
295 if (!a && !b)
296 return 1;
297 return a->ce_mode == b->ce_mode &&
298 !memcmp(a->sha1, b->sha1, 20);
299}
300
301
302/*
303 * When a CE gets turned into an unmerged entry, we
304 * want it to be up-to-date
305 */
306static void verify_uptodate(struct cache_entry *ce)
307{
308 struct stat st;
309
Junio C Hamano720d1502005-09-11 00:46:27[diff] [blame]310 if (index_only)
311 return;
312
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]313 if (!lstat(ce->name, &st)) {
314 unsigned changed = ce_match_stat(ce, &st);
315 if (!changed)
316 return;
317 errno = 0;
318 }
319 if (errno == ENOENT)
320 return;
321 die("Entry '%s' not uptodate. Cannot merge.", ce->name);
322}
323
324static int merged_entry(struct cache_entry *merge, struct cache_entry *old)
325{
326 merge->ce_flags |= htons(CE_UPDATE);
327 if (old) {
328 /*
329 * See if we can re-use the old CE directly?
330 * That way we get the uptodate stat info.
331 *
332 * This also removes the UPDATE flag on
333 * a match.
334 */
335 if (same(old, merge)) {
336 *merge = *old;
337 } else {
338 verify_uptodate(old);
339 }
340 }
341 merge->ce_flags &= ~htons(CE_STAGEMASK);
342 add_cache_entry(merge, ADD_CACHE_OK_TO_ADD);
343 return 1;
344}
345
346static int deleted_entry(struct cache_entry *ce, struct cache_entry *old)
347{
348 if (old)
349 verify_uptodate(old);
350 ce->ce_mode = 0;
351 add_cache_entry(ce, ADD_CACHE_OK_TO_ADD);
352 return 1;
353}
354
355static int keep_entry(struct cache_entry *ce)
356{
357 add_cache_entry(ce, ADD_CACHE_OK_TO_ADD);
358 return 1;
359}
360
Junio C Hamano4d3fe0c2005-09-06 19:53:56[diff] [blame]361#if DBRT_DEBUG
362static void show_stage_entry(FILE *o,
363 const char *label, const struct cache_entry *ce)
364{
Junio C Hamano2ba6c472005-09-14 05:27:42[diff] [blame]365 if (!ce)
366 fprintf(o, "%s (missing)\n", label);
367 else
368 fprintf(o, "%s%06o %s %d\t%s\n",
369 label,
370 ntohl(ce->ce_mode),
371 sha1_to_hex(ce->sha1),
372 ce_stage(ce),
373 ce->name);
Junio C Hamano4d3fe0c2005-09-06 19:53:56[diff] [blame]374}
375#endif
376
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]377static int threeway_merge(struct cache_entry **stages)
378{
379 struct cache_entry *index;
380 struct cache_entry *head;
381 struct cache_entry *remote = stages[head_idx + 1];
382 int count;
383 int head_match = 0;
384 int remote_match = 0;
385
386 int df_conflict_head = 0;
387 int df_conflict_remote = 0;
388
389 int any_anc_missing = 0;
390 int i;
391
392 for (i = 1; i < head_idx; i++) {
393 if (!stages[i])
394 any_anc_missing = 1;
395 }
396
397 index = stages[0];
398 head = stages[head_idx];
399
400 if (head == &df_conflict_entry) {
401 df_conflict_head = 1;
402 head = NULL;
403 }
404
405 if (remote == &df_conflict_entry) {
406 df_conflict_remote = 1;
407 remote = NULL;
408 }
409
410 /* First, if there's a #16 situation, note that to prevent #13
411 * and #14.
412 */
413 if (!same(remote, head)) {
414 for (i = 1; i < head_idx; i++) {
415 if (same(stages[i], head)) {
Junio C Hamano4d3fe0c2005-09-06 19:53:56[diff] [blame]416 head_match = i;
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]417 }
418 if (same(stages[i], remote)) {
Junio C Hamano4d3fe0c2005-09-06 19:53:56[diff] [blame]419 remote_match = i;
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]420 }
421 }
422 }
423
424 /* We start with cases where the index is allowed to match
425 * something other than the head: #14(ALT) and #2ALT, where it
426 * is permitted to match the result instead.
427 */
428 /* #14, #14ALT, #2ALT */
429 if (remote && !df_conflict_head && head_match && !remote_match) {
430 if (index && !same(index, remote) && !same(index, head))
431 reject_merge(index);
432 return merged_entry(remote, index);
433 }
434 /*
435 * If we have an entry in the index cache, then we want to
436 * make sure that it matches head.
437 */
438 if (index && !same(index, head)) {
439 reject_merge(index);
440 }
441
442 if (head) {
443 /* #5ALT, #15 */
444 if (same(head, remote))
445 return merged_entry(head, index);
446 /* #13, #3ALT */
447 if (!df_conflict_remote && remote_match && !head_match)
448 return merged_entry(head, index);
449 }
450
451 /* #1 */
452 if (!head && !remote && any_anc_missing)
453 return 0;
454
455 /* Below are "no merge" cases, which require that the index be
456 * up-to-date to avoid the files getting overwritten with
457 * conflict resolution files.
458 */
459 if (index) {
460 verify_uptodate(index);
461 }
462
463 /* #2, #3, #4, #6, #7, #9, #11. */
464 count = 0;
465 if (!head_match || !remote_match) {
466 for (i = 1; i < head_idx; i++) {
467 if (stages[i]) {
468 keep_entry(stages[i]);
469 count++;
470 break;
471 }
472 }
473 }
Junio C Hamano4d3fe0c2005-09-06 19:53:56[diff] [blame]474#if DBRT_DEBUG
475 else {
476 fprintf(stderr, "read-tree: warning #16 detected\n");
477 show_stage_entry(stderr, "head ", stages[head_match]);
478 show_stage_entry(stderr, "remote ", stages[remote_match]);
479 }
480#endif
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]481 if (head) { count += keep_entry(head); }
482 if (remote) { count += keep_entry(remote); }
483 return count;
484}
485
486/*
487 * Two-way merge.
488 *
489 * The rule is to "carry forward" what is in the index without losing
490 * information across a "fast forward", favoring a successful merge
491 * over a merge failure when it makes sense. For details of the
492 * "carry forward" rule, please see <Documentation/git-read-tree.txt>.
493 *
494 */
495static int twoway_merge(struct cache_entry **src)
496{
497 struct cache_entry *current = src[0];
498 struct cache_entry *oldtree = src[1], *newtree = src[2];
499
500 if (merge_size != 2)
501 return error("Cannot do a twoway merge of %d trees\n",
502 merge_size);
503
504 if (current) {
505 if ((!oldtree && !newtree) || /* 4 and 5 */
506 (!oldtree && newtree &&
507 same(current, newtree)) || /* 6 and 7 */
508 (oldtree && newtree &&
509 same(oldtree, newtree)) || /* 14 and 15 */
510 (oldtree && newtree &&
511 !same(oldtree, newtree) && /* 18 and 19*/
512 same(current, newtree))) {
513 return keep_entry(current);
514 }
515 else if (oldtree && !newtree && same(current, oldtree)) {
516 /* 10 or 11 */
517 return deleted_entry(oldtree, current);
518 }
519 else if (oldtree && newtree &&
520 same(current, oldtree) && !same(current, newtree)) {
521 /* 20 or 21 */
522 return merged_entry(newtree, current);
523 }
524 else {
525 /* all other failures */
526 if (oldtree)
527 reject_merge(oldtree);
528 if (current)
529 reject_merge(current);
530 if (newtree)
531 reject_merge(newtree);
532 return -1;
533 }
534 }
535 else if (newtree)
536 return merged_entry(newtree, current);
537 else
538 return deleted_entry(oldtree, current);
539}
540
541/*
542 * One-way merge.
543 *
544 * The rule is:
545 * - take the stat information from stage0, take the data from stage1
546 */
547static int oneway_merge(struct cache_entry **src)
548{
549 struct cache_entry *old = src[0];
550 struct cache_entry *a = src[1];
551
552 if (merge_size != 1)
553 return error("Cannot do a oneway merge of %d trees\n",
554 merge_size);
555
556 if (!a)
557 return 0;
558 if (old && same(old, a)) {
559 return keep_entry(old);
560 }
561 return merged_entry(a, NULL);
Linus Torvaldsd723c692005-06-06 21:01:58[diff] [blame]562}
563
Linus Torvalds438195c2005-06-09 19:51:01[diff] [blame]564static int read_cache_unmerged(void)
565{
566 int i, deleted;
567 struct cache_entry **dst;
568
569 read_cache();
570 dst = active_cache;
571 deleted = 0;
572 for (i = 0; i < active_nr; i++) {
573 struct cache_entry *ce = active_cache[i];
574 if (ce_stage(ce)) {
575 deleted++;
576 continue;
577 }
578 if (deleted)
579 *dst = ce;
580 dst++;
581 }
582 active_nr -= deleted;
583 return deleted;
584}
585
Junio C Hamano720d1502005-09-11 00:46:27[diff] [blame]586static const char read_tree_usage[] = "git-read-tree (<sha> | -m [-u | -i] <sha1> [<sha2> [<sha3>]])";
Junio C Hamanoc5bac172005-04-21 02:49:16[diff] [blame]587
Junio C Hamano96cd5422005-06-06 19:20:55[diff] [blame]588static struct cache_file cache_file;
589
Linus Torvaldse83c5162005-04-07 22:13:13[diff] [blame]590int main(int argc, char **argv)
591{
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]592 int i, newfd, reset, stage = 0;
Linus Torvaldse83c5162005-04-07 22:13:13[diff] [blame]593 unsigned char sha1[20];
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]594 merge_fn_t fn = NULL;
Linus Torvaldse83c5162005-04-07 22:13:13[diff] [blame]595
Junio C Hamano96cd5422005-06-06 19:20:55[diff] [blame]596 newfd = hold_index_file_for_update(&cache_file, get_index_file());
Linus Torvalds83adac32005-04-09 19:11:25[diff] [blame]597 if (newfd < 0)
Petr Baudis2de381f2005-04-13 09:28:48[diff] [blame]598 die("unable to create new cachefile");
Linus Torvalds83adac32005-04-09 19:11:25[diff] [blame]599
Linus Torvaldsca016f02005-04-19 18:16:12[diff] [blame]600 merge = 0;
Linus Torvalds438195c2005-06-09 19:51:01[diff] [blame]601 reset = 0;
Linus Torvalds83adac32005-04-09 19:11:25[diff] [blame]602 for (i = 1; i < argc; i++) {
603 const char *arg = argv[i];
604
Junio C Hamano720d1502005-09-11 00:46:27[diff] [blame]605 /* "-u" means "update", meaning that a merge will update
606 * the working tree.
607 */
Linus Torvalds220a0b52005-06-06 05:07:31[diff] [blame]608 if (!strcmp(arg, "-u")) {
609 update = 1;
610 continue;
611 }
612
Junio C Hamano720d1502005-09-11 00:46:27[diff] [blame]613 /* "-i" means "index only", meaning that a merge will
614 * not even look at the working tree.
615 */
616 if (!strcmp(arg, "-i")) {
617 index_only = 1;
618 continue;
619 }
620
Linus Torvalds438195c2005-06-09 19:51:01[diff] [blame]621 /* This differs from "-m" in that we'll silently ignore unmerged entries */
622 if (!strcmp(arg, "--reset")) {
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]623 if (stage || merge)
Linus Torvalds438195c2005-06-09 19:51:01[diff] [blame]624 usage(read_tree_usage);
625 reset = 1;
626 merge = 1;
627 stage = 1;
628 read_cache_unmerged();
Linus Torvalds7875b502005-06-15 17:25:46[diff] [blame]629 continue;
Linus Torvalds438195c2005-06-09 19:51:01[diff] [blame]630 }
631
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]632 if (!strcmp(arg, "--head")) {
633 head_idx = stage - 1;
634 fn = threeway_merge;
635 }
636
Linus Torvaldsd99082e2005-04-16 05:53:45[diff] [blame]637 /* "-m" stands for "merge", meaning we start in stage 1 */
Linus Torvalds83adac32005-04-09 19:11:25[diff] [blame]638 if (!strcmp(arg, "-m")) {
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]639 if (stage || merge)
Linus Torvalds438195c2005-06-09 19:51:01[diff] [blame]640 usage(read_tree_usage);
641 if (read_cache_unmerged())
642 die("you need to resolve your current index first");
Linus Torvaldsd99082e2005-04-16 05:53:45[diff] [blame]643 stage = 1;
Linus Torvaldsca016f02005-04-19 18:16:12[diff] [blame]644 merge = 1;
Linus Torvalds83adac32005-04-09 19:11:25[diff] [blame]645 continue;
646 }
Junio C Hamano03efa6d2005-06-11 01:36:08[diff] [blame]647
Junio C Hamano720d1502005-09-11 00:46:27[diff] [blame]648 /* using -u and -i at the same time makes no sense */
649 if (1 < index_only + update)
650 usage(read_tree_usage);
651
Linus Torvalds3c249c92005-05-01 23:36:56[diff] [blame]652 if (get_sha1(arg, sha1) < 0)
Junio C Hamanoc5bac172005-04-21 02:49:16[diff] [blame]653 usage(read_tree_usage);
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]654 if (list_tree(sha1) < 0)
Petr Baudis2de381f2005-04-13 09:28:48[diff] [blame]655 die("failed to unpack tree object %s", arg);
Linus Torvaldsd99082e2005-04-16 05:53:45[diff] [blame]656 stage++;
Linus Torvalds83adac32005-04-09 19:11:25[diff] [blame]657 }
Linus Torvaldsa57f0b52005-06-07 22:20:39[diff] [blame]658 if (update && !merge)
659 usage(read_tree_usage);
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]660 if (merge && !fn) {
661 if (stage < 2)
Linus Torvaldsa3a65232005-04-19 18:41:18[diff] [blame]662 die("just how do you expect me to merge %d trees?", stage-1);
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]663 switch (stage - 1) {
664 case 1:
665 fn = oneway_merge;
666 break;
667 case 2:
668 fn = twoway_merge;
669 break;
670 case 3:
671 fn = threeway_merge;
672 break;
673 default:
674 fn = threeway_merge;
675 break;
Junio C Hamano03efa6d2005-06-11 01:36:08[diff] [blame]676 }
Linus Torvaldsca016f02005-04-19 18:16:12[diff] [blame]677 }
Daniel Barkalowee6566e2005-09-05 06:04:48[diff] [blame]678
679 if (head_idx < 0) {
680 if (stage - 1 >= 3)
681 head_idx = stage - 2;
682 else
683 head_idx = 1;
684 }
685
686 unpack_trees(fn);
Junio C Hamano96cd5422005-06-06 19:20:55[diff] [blame]687 if (write_cache(newfd, active_cache, active_nr) ||
688 commit_index_file(&cache_file))
Petr Baudis2de381f2005-04-13 09:28:48[diff] [blame]689 die("unable to write new index file");
Linus Torvalds9614b8d2005-04-11 22:39:26[diff] [blame]690 return 0;
Linus Torvaldse83c5162005-04-07 22:13:13[diff] [blame]691}