merge: abort if fails to commit
[git/git.git] / notes-merge.c
CommitLineData
75ef3f4a
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1#include "cache.h"
2#include "commit.h"
3#include "refs.h"
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4#include "diff.h"
5#include "diffcore.h"
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6#include "xdiff-interface.h"
7#include "ll-merge.h"
8#include "dir.h"
56881843 9#include "notes.h"
75ef3f4a 10#include "notes-merge.h"
443259cf 11#include "strbuf.h"
75ef3f4a 12
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13struct notes_merge_pair {
14 unsigned char obj[20], base[20], local[20], remote[20];
15};
16
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17void init_notes_merge_options(struct notes_merge_options *o)
18{
19 memset(o, 0, sizeof(struct notes_merge_options));
443259cf 20 strbuf_init(&(o->commit_msg), 0);
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21 o->verbosity = NOTES_MERGE_VERBOSITY_DEFAULT;
22}
23
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24static int path_to_sha1(const char *path, unsigned char *sha1)
25{
26 char hex_sha1[40];
27 int i = 0;
28 while (*path && i < 40) {
29 if (*path != '/')
30 hex_sha1[i++] = *path;
31 path++;
32 }
33 if (*path || i != 40)
34 return -1;
35 return get_sha1_hex(hex_sha1, sha1);
36}
37
38static int verify_notes_filepair(struct diff_filepair *p, unsigned char *sha1)
39{
40 switch (p->status) {
41 case DIFF_STATUS_MODIFIED:
42 assert(p->one->mode == p->two->mode);
43 assert(!is_null_sha1(p->one->sha1));
44 assert(!is_null_sha1(p->two->sha1));
45 break;
46 case DIFF_STATUS_ADDED:
47 assert(is_null_sha1(p->one->sha1));
48 break;
49 case DIFF_STATUS_DELETED:
50 assert(is_null_sha1(p->two->sha1));
51 break;
52 default:
53 return -1;
54 }
55 assert(!strcmp(p->one->path, p->two->path));
56 return path_to_sha1(p->one->path, sha1);
57}
58
59static struct notes_merge_pair *find_notes_merge_pair_pos(
60 struct notes_merge_pair *list, int len, unsigned char *obj,
61 int insert_new, int *occupied)
62{
63 /*
64 * Both diff_tree_remote() and diff_tree_local() tend to process
65 * merge_pairs in ascending order. Therefore, cache last returned
66 * index, and search sequentially from there until the appropriate
67 * position is found.
68 *
69 * Since inserts only happen from diff_tree_remote() (which mainly
70 * _appends_), we don't care that inserting into the middle of the
71 * list is expensive (using memmove()).
72 */
73 static int last_index;
74 int i = last_index < len ? last_index : len - 1;
75 int prev_cmp = 0, cmp = -1;
76 while (i >= 0 && i < len) {
77 cmp = hashcmp(obj, list[i].obj);
78 if (!cmp) /* obj belongs @ i */
79 break;
80 else if (cmp < 0 && prev_cmp <= 0) /* obj belongs < i */
81 i--;
82 else if (cmp < 0) /* obj belongs between i-1 and i */
83 break;
84 else if (cmp > 0 && prev_cmp >= 0) /* obj belongs > i */
85 i++;
86 else /* if (cmp > 0) */ { /* obj belongs between i and i+1 */
87 i++;
88 break;
89 }
90 prev_cmp = cmp;
91 }
92 if (i < 0)
93 i = 0;
94 /* obj belongs at, or immediately preceding, index i (0 <= i <= len) */
95
96 if (!cmp)
97 *occupied = 1;
98 else {
99 *occupied = 0;
100 if (insert_new && i < len) {
101 memmove(list + i + 1, list + i,
102 (len - i) * sizeof(struct notes_merge_pair));
103 memset(list + i, 0, sizeof(struct notes_merge_pair));
104 }
105 }
106 last_index = i;
107 return list + i;
108}
109
110static unsigned char uninitialized[20] =
111 "\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" \
112 "\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff";
113
114static struct notes_merge_pair *diff_tree_remote(struct notes_merge_options *o,
115 const unsigned char *base,
116 const unsigned char *remote,
117 int *num_changes)
118{
119 struct diff_options opt;
120 struct notes_merge_pair *changes;
121 int i, len = 0;
122
123 trace_printf("\tdiff_tree_remote(base = %.7s, remote = %.7s)\n",
124 sha1_to_hex(base), sha1_to_hex(remote));
125
126 diff_setup(&opt);
127 DIFF_OPT_SET(&opt, RECURSIVE);
128 opt.output_format = DIFF_FORMAT_NO_OUTPUT;
129 if (diff_setup_done(&opt) < 0)
130 die("diff_setup_done failed");
131 diff_tree_sha1(base, remote, "", &opt);
132 diffcore_std(&opt);
133
134 changes = xcalloc(diff_queued_diff.nr, sizeof(struct notes_merge_pair));
135
136 for (i = 0; i < diff_queued_diff.nr; i++) {
137 struct diff_filepair *p = diff_queued_diff.queue[i];
138 struct notes_merge_pair *mp;
139 int occupied;
140 unsigned char obj[20];
141
142 if (verify_notes_filepair(p, obj)) {
143 trace_printf("\t\tCannot merge entry '%s' (%c): "
144 "%.7s -> %.7s. Skipping!\n", p->one->path,
145 p->status, sha1_to_hex(p->one->sha1),
146 sha1_to_hex(p->two->sha1));
147 continue;
148 }
149 mp = find_notes_merge_pair_pos(changes, len, obj, 1, &occupied);
150 if (occupied) {
151 /* We've found an addition/deletion pair */
152 assert(!hashcmp(mp->obj, obj));
153 if (is_null_sha1(p->one->sha1)) { /* addition */
154 assert(is_null_sha1(mp->remote));
155 hashcpy(mp->remote, p->two->sha1);
156 } else if (is_null_sha1(p->two->sha1)) { /* deletion */
157 assert(is_null_sha1(mp->base));
158 hashcpy(mp->base, p->one->sha1);
159 } else
160 assert(!"Invalid existing change recorded");
161 } else {
162 hashcpy(mp->obj, obj);
163 hashcpy(mp->base, p->one->sha1);
164 hashcpy(mp->local, uninitialized);
165 hashcpy(mp->remote, p->two->sha1);
166 len++;
167 }
168 trace_printf("\t\tStored remote change for %s: %.7s -> %.7s\n",
169 sha1_to_hex(mp->obj), sha1_to_hex(mp->base),
170 sha1_to_hex(mp->remote));
171 }
172 diff_flush(&opt);
173 diff_tree_release_paths(&opt);
174
175 *num_changes = len;
176 return changes;
177}
178
179static void diff_tree_local(struct notes_merge_options *o,
180 struct notes_merge_pair *changes, int len,
181 const unsigned char *base,
182 const unsigned char *local)
183{
184 struct diff_options opt;
185 int i;
186
187 trace_printf("\tdiff_tree_local(len = %i, base = %.7s, local = %.7s)\n",
188 len, sha1_to_hex(base), sha1_to_hex(local));
189
190 diff_setup(&opt);
191 DIFF_OPT_SET(&opt, RECURSIVE);
192 opt.output_format = DIFF_FORMAT_NO_OUTPUT;
193 if (diff_setup_done(&opt) < 0)
194 die("diff_setup_done failed");
195 diff_tree_sha1(base, local, "", &opt);
196 diffcore_std(&opt);
197
198 for (i = 0; i < diff_queued_diff.nr; i++) {
199 struct diff_filepair *p = diff_queued_diff.queue[i];
200 struct notes_merge_pair *mp;
201 int match;
202 unsigned char obj[20];
203
204 if (verify_notes_filepair(p, obj)) {
205 trace_printf("\t\tCannot merge entry '%s' (%c): "
206 "%.7s -> %.7s. Skipping!\n", p->one->path,
207 p->status, sha1_to_hex(p->one->sha1),
208 sha1_to_hex(p->two->sha1));
209 continue;
210 }
211 mp = find_notes_merge_pair_pos(changes, len, obj, 0, &match);
212 if (!match) {
213 trace_printf("\t\tIgnoring local-only change for %s: "
214 "%.7s -> %.7s\n", sha1_to_hex(obj),
215 sha1_to_hex(p->one->sha1),
216 sha1_to_hex(p->two->sha1));
217 continue;
218 }
219
220 assert(!hashcmp(mp->obj, obj));
221 if (is_null_sha1(p->two->sha1)) { /* deletion */
222 /*
223 * Either this is a true deletion (1), or it is part
224 * of an A/D pair (2), or D/A pair (3):
225 *
226 * (1) mp->local is uninitialized; set it to null_sha1
227 * (2) mp->local is not uninitialized; don't touch it
228 * (3) mp->local is uninitialized; set it to null_sha1
229 * (will be overwritten by following addition)
230 */
231 if (!hashcmp(mp->local, uninitialized))
232 hashclr(mp->local);
233 } else if (is_null_sha1(p->one->sha1)) { /* addition */
234 /*
235 * Either this is a true addition (1), or it is part
236 * of an A/D pair (2), or D/A pair (3):
237 *
238 * (1) mp->local is uninitialized; set to p->two->sha1
239 * (2) mp->local is uninitialized; set to p->two->sha1
240 * (3) mp->local is null_sha1; set to p->two->sha1
241 */
242 assert(is_null_sha1(mp->local) ||
243 !hashcmp(mp->local, uninitialized));
244 hashcpy(mp->local, p->two->sha1);
245 } else { /* modification */
246 /*
247 * This is a true modification. p->one->sha1 shall
248 * match mp->base, and mp->local shall be uninitialized.
249 * Set mp->local to p->two->sha1.
250 */
251 assert(!hashcmp(p->one->sha1, mp->base));
252 assert(!hashcmp(mp->local, uninitialized));
253 hashcpy(mp->local, p->two->sha1);
254 }
255 trace_printf("\t\tStored local change for %s: %.7s -> %.7s\n",
256 sha1_to_hex(mp->obj), sha1_to_hex(mp->base),
257 sha1_to_hex(mp->local));
258 }
259 diff_flush(&opt);
260 diff_tree_release_paths(&opt);
261}
262
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263static void check_notes_merge_worktree(struct notes_merge_options *o)
264{
265 if (!o->has_worktree) {
266 /*
267 * Must establish NOTES_MERGE_WORKTREE.
268 * Abort if NOTES_MERGE_WORKTREE already exists
269 */
270 if (file_exists(git_path(NOTES_MERGE_WORKTREE))) {
271 if (advice_resolve_conflict)
272 die("You have not concluded your previous "
273 "notes merge (%s exists).\nPlease, use "
274 "'git notes merge --commit' or 'git notes "
6abb3655 275 "merge --abort' to commit/abort the "
809f38c8
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276 "previous merge before you start a new "
277 "notes merge.", git_path("NOTES_MERGE_*"));
278 else
279 die("You have not concluded your notes merge "
280 "(%s exists).", git_path("NOTES_MERGE_*"));
281 }
282
283 if (safe_create_leading_directories(git_path(
284 NOTES_MERGE_WORKTREE "/.test")))
285 die_errno("unable to create directory %s",
286 git_path(NOTES_MERGE_WORKTREE));
287 o->has_worktree = 1;
288 } else if (!file_exists(git_path(NOTES_MERGE_WORKTREE)))
289 /* NOTES_MERGE_WORKTREE should already be established */
290 die("missing '%s'. This should not happen",
291 git_path(NOTES_MERGE_WORKTREE));
292}
293
294static void write_buf_to_worktree(const unsigned char *obj,
295 const char *buf, unsigned long size)
296{
297 int fd;
298 char *path = git_path(NOTES_MERGE_WORKTREE "/%s", sha1_to_hex(obj));
299 if (safe_create_leading_directories(path))
300 die_errno("unable to create directory for '%s'", path);
301 if (file_exists(path))
302 die("found existing file at '%s'", path);
303
304 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, 0666);
305 if (fd < 0)
306 die_errno("failed to open '%s'", path);
307
308 while (size > 0) {
309 long ret = write_in_full(fd, buf, size);
310 if (ret < 0) {
311 /* Ignore epipe */
312 if (errno == EPIPE)
313 break;
314 die_errno("notes-merge");
315 } else if (!ret) {
316 die("notes-merge: disk full?");
317 }
318 size -= ret;
319 buf += ret;
320 }
321
322 close(fd);
323}
324
325static void write_note_to_worktree(const unsigned char *obj,
326 const unsigned char *note)
327{
328 enum object_type type;
329 unsigned long size;
330 void *buf = read_sha1_file(note, &type, &size);
331
332 if (!buf)
333 die("cannot read note %s for object %s",
334 sha1_to_hex(note), sha1_to_hex(obj));
335 if (type != OBJ_BLOB)
336 die("blob expected in note %s for object %s",
337 sha1_to_hex(note), sha1_to_hex(obj));
338 write_buf_to_worktree(obj, buf, size);
339 free(buf);
340}
341
342static int ll_merge_in_worktree(struct notes_merge_options *o,
343 struct notes_merge_pair *p)
344{
345 mmbuffer_t result_buf;
346 mmfile_t base, local, remote;
347 int status;
348
349 read_mmblob(&base, p->base);
350 read_mmblob(&local, p->local);
351 read_mmblob(&remote, p->remote);
352
353 status = ll_merge(&result_buf, sha1_to_hex(p->obj), &base, NULL,
c2e86add 354 &local, o->local_ref, &remote, o->remote_ref, NULL);
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355
356 free(base.ptr);
357 free(local.ptr);
358 free(remote.ptr);
359
360 if ((status < 0) || !result_buf.ptr)
361 die("Failed to execute internal merge");
362
363 write_buf_to_worktree(p->obj, result_buf.ptr, result_buf.size);
364 free(result_buf.ptr);
365
366 return status;
367}
368
369static int merge_one_change_manual(struct notes_merge_options *o,
370 struct notes_merge_pair *p,
371 struct notes_tree *t)
372{
373 const char *lref = o->local_ref ? o->local_ref : "local version";
374 const char *rref = o->remote_ref ? o->remote_ref : "remote version";
375
376 trace_printf("\t\t\tmerge_one_change_manual(obj = %.7s, base = %.7s, "
377 "local = %.7s, remote = %.7s)\n",
378 sha1_to_hex(p->obj), sha1_to_hex(p->base),
379 sha1_to_hex(p->local), sha1_to_hex(p->remote));
380
443259cf
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381 /* add "Conflicts:" section to commit message first time through */
382 if (!o->has_worktree)
383 strbuf_addstr(&(o->commit_msg), "\n\nConflicts:\n");
384
385 strbuf_addf(&(o->commit_msg), "\t%s\n", sha1_to_hex(p->obj));
386
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387 if (o->verbosity >= 2)
388 printf("Auto-merging notes for %s\n", sha1_to_hex(p->obj));
809f38c8
JH
389 check_notes_merge_worktree(o);
390 if (is_null_sha1(p->local)) {
391 /* D/F conflict, checkout p->remote */
392 assert(!is_null_sha1(p->remote));
5f9f8d15
JN
393 if (o->verbosity >= 1)
394 printf("CONFLICT (delete/modify): Notes for object %s "
395 "deleted in %s and modified in %s. Version from %s "
396 "left in tree.\n",
397 sha1_to_hex(p->obj), lref, rref, rref);
809f38c8
JH
398 write_note_to_worktree(p->obj, p->remote);
399 } else if (is_null_sha1(p->remote)) {
400 /* D/F conflict, checkout p->local */
401 assert(!is_null_sha1(p->local));
5f9f8d15
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402 if (o->verbosity >= 1)
403 printf("CONFLICT (delete/modify): Notes for object %s "
404 "deleted in %s and modified in %s. Version from %s "
405 "left in tree.\n",
406 sha1_to_hex(p->obj), rref, lref, lref);
809f38c8
JH
407 write_note_to_worktree(p->obj, p->local);
408 } else {
409 /* "regular" conflict, checkout result of ll_merge() */
410 const char *reason = "content";
411 if (is_null_sha1(p->base))
412 reason = "add/add";
413 assert(!is_null_sha1(p->local));
414 assert(!is_null_sha1(p->remote));
5f9f8d15
JN
415 if (o->verbosity >= 1)
416 printf("CONFLICT (%s): Merge conflict in notes for "
417 "object %s\n", reason, sha1_to_hex(p->obj));
809f38c8
JH
418 ll_merge_in_worktree(o, p);
419 }
420
421 trace_printf("\t\t\tremoving from partial merge result\n");
422 remove_note(t, p->obj);
423
424 return 1;
425}
426
3228e671
JH
427static int merge_one_change(struct notes_merge_options *o,
428 struct notes_merge_pair *p, struct notes_tree *t)
429{
430 /*
809f38c8
JH
431 * Return 0 if change is successfully resolved (stored in notes_tree).
432 * Return 1 is change results in a conflict (NOT stored in notes_tree,
433 * but instead written to NOTES_MERGE_WORKTREE with conflict markers).
3228e671
JH
434 */
435 switch (o->strategy) {
436 case NOTES_MERGE_RESOLVE_MANUAL:
809f38c8 437 return merge_one_change_manual(o, p, t);
3228e671 438 case NOTES_MERGE_RESOLVE_OURS:
5f9f8d15
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439 if (o->verbosity >= 2)
440 printf("Using local notes for %s\n",
441 sha1_to_hex(p->obj));
3228e671
JH
442 /* nothing to do */
443 return 0;
444 case NOTES_MERGE_RESOLVE_THEIRS:
5f9f8d15
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445 if (o->verbosity >= 2)
446 printf("Using remote notes for %s\n",
447 sha1_to_hex(p->obj));
3228e671
JH
448 if (add_note(t, p->obj, p->remote, combine_notes_overwrite))
449 die("BUG: combine_notes_overwrite failed");
450 return 0;
451 case NOTES_MERGE_RESOLVE_UNION:
5f9f8d15
JN
452 if (o->verbosity >= 2)
453 printf("Concatenating local and remote notes for %s\n",
454 sha1_to_hex(p->obj));
3228e671
JH
455 if (add_note(t, p->obj, p->remote, combine_notes_concatenate))
456 die("failed to concatenate notes "
457 "(combine_notes_concatenate)");
458 return 0;
a6a09095 459 case NOTES_MERGE_RESOLVE_CAT_SORT_UNIQ:
5f9f8d15
JN
460 if (o->verbosity >= 2)
461 printf("Concatenating unique lines in local and remote "
462 "notes for %s\n", sha1_to_hex(p->obj));
a6a09095
JH
463 if (add_note(t, p->obj, p->remote, combine_notes_cat_sort_uniq))
464 die("failed to concatenate notes "
465 "(combine_notes_cat_sort_uniq)");
466 return 0;
3228e671
JH
467 }
468 die("Unknown strategy (%i).", o->strategy);
469}
470
2085b16a
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471static int merge_changes(struct notes_merge_options *o,
472 struct notes_merge_pair *changes, int *num_changes,
473 struct notes_tree *t)
474{
475 int i, conflicts = 0;
476
477 trace_printf("\tmerge_changes(num_changes = %i)\n", *num_changes);
478 for (i = 0; i < *num_changes; i++) {
479 struct notes_merge_pair *p = changes + i;
480 trace_printf("\t\t%.7s: %.7s -> %.7s/%.7s\n",
481 sha1_to_hex(p->obj), sha1_to_hex(p->base),
482 sha1_to_hex(p->local), sha1_to_hex(p->remote));
483
484 if (!hashcmp(p->base, p->remote)) {
485 /* no remote change; nothing to do */
486 trace_printf("\t\t\tskipping (no remote change)\n");
487 } else if (!hashcmp(p->local, p->remote)) {
488 /* same change in local and remote; nothing to do */
489 trace_printf("\t\t\tskipping (local == remote)\n");
490 } else if (!hashcmp(p->local, uninitialized) ||
491 !hashcmp(p->local, p->base)) {
492 /* no local change; adopt remote change */
493 trace_printf("\t\t\tno local change, adopted remote\n");
494 if (add_note(t, p->obj, p->remote,
495 combine_notes_overwrite))
496 die("BUG: combine_notes_overwrite failed");
497 } else {
498 /* need file-level merge between local and remote */
499 trace_printf("\t\t\tneed content-level merge\n");
3228e671 500 conflicts += merge_one_change(o, p, t);
2085b16a
JH
501 }
502 }
503
504 return conflicts;
505}
506
507static int merge_from_diffs(struct notes_merge_options *o,
508 const unsigned char *base,
509 const unsigned char *local,
510 const unsigned char *remote, struct notes_tree *t)
511{
512 struct notes_merge_pair *changes;
513 int num_changes, conflicts;
514
515 trace_printf("\tmerge_from_diffs(base = %.7s, local = %.7s, "
516 "remote = %.7s)\n", sha1_to_hex(base), sha1_to_hex(local),
517 sha1_to_hex(remote));
518
519 changes = diff_tree_remote(o, base, remote, &num_changes);
520 diff_tree_local(o, changes, num_changes, base, local);
521
522 conflicts = merge_changes(o, changes, &num_changes, t);
523 free(changes);
524
5f9f8d15
JN
525 if (o->verbosity >= 4)
526 printf("Merge result: %i unmerged notes and a %s notes tree\n",
527 conflicts, t->dirty ? "dirty" : "clean");
2085b16a
JH
528
529 return conflicts ? -1 : 1;
530}
531
56881843
JH
532void create_notes_commit(struct notes_tree *t, struct commit_list *parents,
533 const char *msg, unsigned char *result_sha1)
534{
535 unsigned char tree_sha1[20];
536
537 assert(t->initialized);
538
539 if (write_notes_tree(t, tree_sha1))
540 die("Failed to write notes tree to database");
541
542 if (!parents) {
543 /* Deduce parent commit from t->ref */
544 unsigned char parent_sha1[20];
545 if (!read_ref(t->ref, parent_sha1)) {
546 struct commit *parent = lookup_commit(parent_sha1);
547 if (!parent || parse_commit(parent))
548 die("Failed to find/parse commit %s", t->ref);
549 commit_list_insert(parent, &parents);
550 }
551 /* else: t->ref points to nothing, assume root/orphan commit */
552 }
553
554 if (commit_tree(msg, tree_sha1, parents, result_sha1, NULL))
555 die("Failed to commit notes tree to database");
556}
557
75ef3f4a 558int notes_merge(struct notes_merge_options *o,
2085b16a 559 struct notes_tree *local_tree,
75ef3f4a
JH
560 unsigned char *result_sha1)
561{
562 unsigned char local_sha1[20], remote_sha1[20];
563 struct commit *local, *remote;
564 struct commit_list *bases = NULL;
2085b16a 565 const unsigned char *base_sha1, *base_tree_sha1;
75ef3f4a
JH
566 int result = 0;
567
568 assert(o->local_ref && o->remote_ref);
2085b16a 569 assert(!strcmp(o->local_ref, local_tree->ref));
75ef3f4a
JH
570 hashclr(result_sha1);
571
572 trace_printf("notes_merge(o->local_ref = %s, o->remote_ref = %s)\n",
573 o->local_ref, o->remote_ref);
574
575 /* Dereference o->local_ref into local_sha1 */
576 if (!resolve_ref(o->local_ref, local_sha1, 0, NULL))
577 die("Failed to resolve local notes ref '%s'", o->local_ref);
8d9c5010
MH
578 else if (!check_refname_format(o->local_ref, 0) &&
579 is_null_sha1(local_sha1))
75ef3f4a
JH
580 local = NULL; /* local_sha1 == null_sha1 indicates unborn ref */
581 else if (!(local = lookup_commit_reference(local_sha1)))
582 die("Could not parse local commit %s (%s)",
583 sha1_to_hex(local_sha1), o->local_ref);
584 trace_printf("\tlocal commit: %.7s\n", sha1_to_hex(local_sha1));
585
586 /* Dereference o->remote_ref into remote_sha1 */
587 if (get_sha1(o->remote_ref, remote_sha1)) {
588 /*
589 * Failed to get remote_sha1. If o->remote_ref looks like an
590 * unborn ref, perform the merge using an empty notes tree.
591 */
8d9c5010 592 if (!check_refname_format(o->remote_ref, 0)) {
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593 hashclr(remote_sha1);
594 remote = NULL;
595 } else {
596 die("Failed to resolve remote notes ref '%s'",
597 o->remote_ref);
598 }
599 } else if (!(remote = lookup_commit_reference(remote_sha1))) {
600 die("Could not parse remote commit %s (%s)",
601 sha1_to_hex(remote_sha1), o->remote_ref);
602 }
603 trace_printf("\tremote commit: %.7s\n", sha1_to_hex(remote_sha1));
604
605 if (!local && !remote)
606 die("Cannot merge empty notes ref (%s) into empty notes ref "
607 "(%s)", o->remote_ref, o->local_ref);
608 if (!local) {
609 /* result == remote commit */
610 hashcpy(result_sha1, remote_sha1);
611 goto found_result;
612 }
613 if (!remote) {
614 /* result == local commit */
615 hashcpy(result_sha1, local_sha1);
616 goto found_result;
617 }
618 assert(local && remote);
619
620 /* Find merge bases */
621 bases = get_merge_bases(local, remote, 1);
622 if (!bases) {
623 base_sha1 = null_sha1;
dab0d410 624 base_tree_sha1 = EMPTY_TREE_SHA1_BIN;
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625 if (o->verbosity >= 4)
626 printf("No merge base found; doing history-less merge\n");
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627 } else if (!bases->next) {
628 base_sha1 = bases->item->object.sha1;
2085b16a 629 base_tree_sha1 = bases->item->tree->object.sha1;
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630 if (o->verbosity >= 4)
631 printf("One merge base found (%.7s)\n",
632 sha1_to_hex(base_sha1));
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633 } else {
634 /* TODO: How to handle multiple merge-bases? */
635 base_sha1 = bases->item->object.sha1;
2085b16a 636 base_tree_sha1 = bases->item->tree->object.sha1;
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637 if (o->verbosity >= 3)
638 printf("Multiple merge bases found. Using the first "
639 "(%.7s)\n", sha1_to_hex(base_sha1));
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640 }
641
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642 if (o->verbosity >= 4)
643 printf("Merging remote commit %.7s into local commit %.7s with "
644 "merge-base %.7s\n", sha1_to_hex(remote->object.sha1),
645 sha1_to_hex(local->object.sha1),
646 sha1_to_hex(base_sha1));
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647
648 if (!hashcmp(remote->object.sha1, base_sha1)) {
649 /* Already merged; result == local commit */
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650 if (o->verbosity >= 2)
651 printf("Already up-to-date!\n");
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652 hashcpy(result_sha1, local->object.sha1);
653 goto found_result;
654 }
655 if (!hashcmp(local->object.sha1, base_sha1)) {
656 /* Fast-forward; result == remote commit */
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657 if (o->verbosity >= 2)
658 printf("Fast-forward\n");
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659 hashcpy(result_sha1, remote->object.sha1);
660 goto found_result;
661 }
662
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663 result = merge_from_diffs(o, base_tree_sha1, local->tree->object.sha1,
664 remote->tree->object.sha1, local_tree);
665
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666 if (result != 0) { /* non-trivial merge (with or without conflicts) */
667 /* Commit (partial) result */
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668 struct commit_list *parents = NULL;
669 commit_list_insert(remote, &parents); /* LIFO order */
670 commit_list_insert(local, &parents);
443259cf 671 create_notes_commit(local_tree, parents, o->commit_msg.buf,
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672 result_sha1);
673 }
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674
675found_result:
676 free_commit_list(bases);
443259cf 677 strbuf_release(&(o->commit_msg));
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678 trace_printf("notes_merge(): result = %i, result_sha1 = %.7s\n",
679 result, sha1_to_hex(result_sha1));
680 return result;
681}
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682
683int notes_merge_commit(struct notes_merge_options *o,
684 struct notes_tree *partial_tree,
685 struct commit *partial_commit,
686 unsigned char *result_sha1)
687{
688 /*
689 * Iterate through files in .git/NOTES_MERGE_WORKTREE and add all
690 * found notes to 'partial_tree'. Write the updates notes tree to
691 * the DB, and commit the resulting tree object while reusing the
692 * commit message and parents from 'partial_commit'.
693 * Finally store the new commit object SHA1 into 'result_sha1'.
694 */
695 struct dir_struct dir;
85284456 696 char *path = xstrdup(git_path(NOTES_MERGE_WORKTREE "/"));
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697 int path_len = strlen(path), i;
698 const char *msg = strstr(partial_commit->buffer, "\n\n");
699
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700 if (o->verbosity >= 3)
701 printf("Committing notes in notes merge worktree at %.*s\n",
702 path_len - 1, path);
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703
704 if (!msg || msg[2] == '\0')
705 die("partial notes commit has empty message");
706 msg += 2;
707
708 memset(&dir, 0, sizeof(dir));
709 read_directory(&dir, path, path_len, NULL);
710 for (i = 0; i < dir.nr; i++) {
711 struct dir_entry *ent = dir.entries[i];
712 struct stat st;
713 const char *relpath = ent->name + path_len;
714 unsigned char obj_sha1[20], blob_sha1[20];
715
716 if (ent->len - path_len != 40 || get_sha1_hex(relpath, obj_sha1)) {
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717 if (o->verbosity >= 3)
718 printf("Skipping non-SHA1 entry '%s'\n",
719 ent->name);
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720 continue;
721 }
722
723 /* write file as blob, and add to partial_tree */
724 if (stat(ent->name, &st))
725 die_errno("Failed to stat '%s'", ent->name);
c4ce46fc 726 if (index_path(blob_sha1, ent->name, &st, HASH_WRITE_OBJECT))
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727 die("Failed to write blob object from '%s'", ent->name);
728 if (add_note(partial_tree, obj_sha1, blob_sha1, NULL))
729 die("Failed to add resolved note '%s' to notes tree",
730 ent->name);
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731 if (o->verbosity >= 4)
732 printf("Added resolved note for object %s: %s\n",
733 sha1_to_hex(obj_sha1), sha1_to_hex(blob_sha1));
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734 }
735
736 create_notes_commit(partial_tree, partial_commit->parents, msg,
737 result_sha1);
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738 if (o->verbosity >= 4)
739 printf("Finalized notes merge commit: %s\n",
740 sha1_to_hex(result_sha1));
85284456 741 free(path);
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742 return 0;
743}
744
745int notes_merge_abort(struct notes_merge_options *o)
746{
747 /* Remove .git/NOTES_MERGE_WORKTREE directory and all files within */
748 struct strbuf buf = STRBUF_INIT;
749 int ret;
750
751 strbuf_addstr(&buf, git_path(NOTES_MERGE_WORKTREE));
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752 if (o->verbosity >= 3)
753 printf("Removing notes merge worktree at %s\n", buf.buf);
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754 ret = remove_dir_recursively(&buf, 0);
755 strbuf_release(&buf);
756 return ret;
757}