1/*
2 * Recursive Merge algorithm stolen from git-merge-recursive.py by
3 * Fredrik Kuivinen.
4 * The thieves were Alex Riesen and Johannes Schindelin, in June/July 2006
5 */
6#include "cache.h"
7#include "cache-tree.h"
8#include "commit.h"
9#include "blob.h"
10#include "builtin.h"
11#include "tree-walk.h"
12#include "diff.h"
13#include "diffcore.h"
14#include "run-command.h"
15#include "tag.h"
16#include "unpack-trees.h"
17#include "path-list.h"
18#include "xdiff-interface.h"
19#include "interpolate.h"
20#include "attr.h"
21#include "merge-recursive.h"
22static int subtree_merge;
24static struct tree *shift_tree_object(struct tree *one, struct tree *two)
26{
27 unsigned char shifted[20];
28 /*
30 * NEEDSWORK: this limits the recursion depth to hardcoded
31 * value '2' to avoid excessive overhead.
32 */
33 shift_tree(one->object.sha1, two->object.sha1, shifted, 2);
34 if (!hashcmp(two->object.sha1, shifted))
35 return two;
36 return lookup_tree(shifted);
37}
38/*
40 * A virtual commit has
41 * - (const char *)commit->util set to the name, and
42 * - *(int *)commit->object.sha1 set to the virtual id.
43 */
44static unsigned commit_list_count(const struct commit_list *l)
46{
47 unsigned c = 0;
48 for (; l; l = l->next )
49 c++;
50 return c;
51}
52static struct commit *make_virtual_commit(struct tree *tree, const char *comment)
54{
55 struct commit *commit = xcalloc(1, sizeof(struct commit));
56 static unsigned virtual_id = 1;
57 commit->tree = tree;
58 commit->util = (void*)comment;
59 *(int*)commit->object.sha1 = virtual_id++;
60 /* avoid warnings */
61 commit->object.parsed = 1;
62 return commit;
63}
64/*
66 * Since we use get_tree_entry(), which does not put the read object into
67 * the object pool, we cannot rely on a == b.
68 */
69static int sha_eq(const unsigned char *a, const unsigned char *b)
70{
71 if (!a && !b)
72 return 2;
73 return a && b && hashcmp(a, b) == 0;
74}
75/*
77 * Since we want to write the index eventually, we cannot reuse the index
78 * for these (temporary) data.
79 */
80struct stage_data
81{
82 struct
83 {
84 unsigned mode;
85 unsigned char sha[20];
86 } stages[4];
87 unsigned processed:1;
88};
89static struct path_list current_file_set = {NULL, 0, 0, 1};
91static struct path_list current_directory_set = {NULL, 0, 0, 1};
92static int call_depth = 0;
94static int verbosity = 2;
95static int rename_limit = -1;
96static int buffer_output = 1;
97static struct strbuf obuf = STRBUF_INIT;
98static int show(int v)
100{
101 return (!call_depth && verbosity >= v) || verbosity >= 5;
102}
103static void flush_output(void)
105{
106 if (obuf.len) {
107 fputs(obuf.buf, stdout);
108 strbuf_reset(&obuf);
109 }
110}
111static void output(int v, const char *fmt, ...)
113{
114 int len;
115 va_list ap;
116 if (!show(v))
118 return;
119 strbuf_grow(&obuf, call_depth * 2 + 2);
121 memset(obuf.buf + obuf.len, ' ', call_depth * 2);
122 strbuf_setlen(&obuf, obuf.len + call_depth * 2);
123 va_start(ap, fmt);
125 len = vsnprintf(obuf.buf + obuf.len, strbuf_avail(&obuf), fmt, ap);
126 va_end(ap);
127 if (len < 0)
129 len = 0;
130 if (len >= strbuf_avail(&obuf)) {
131 strbuf_grow(&obuf, len + 2);
132 va_start(ap, fmt);
133 len = vsnprintf(obuf.buf + obuf.len, strbuf_avail(&obuf), fmt, ap);
134 va_end(ap);
135 if (len >= strbuf_avail(&obuf)) {
136 die("this should not happen, your snprintf is broken");
137 }
138 }
139 strbuf_setlen(&obuf, obuf.len + len);
140 strbuf_add(&obuf, "\n", 1);
141 if (!buffer_output)
142 flush_output();
143}
144static void output_commit_title(struct commit *commit)
146{
147 int i;
148 flush_output();
149 for (i = call_depth; i--;)
150 fputs(" ", stdout);
151 if (commit->util)
152 printf("virtual %s\n", (char *)commit->util);
153 else {
154 printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
155 if (parse_commit(commit) != 0)
156 printf("(bad commit)\n");
157 else {
158 const char *s;
159 int len;
160 for (s = commit->buffer; *s; s++)
161 if (*s == '\n' && s[1] == '\n') {
162 s += 2;
163 break;
164 }
165 for (len = 0; s[len] && '\n' != s[len]; len++)
166 ; /* do nothing */
167 printf("%.*s\n", len, s);
168 }
169 }
170}
171static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
173 const char *path, int stage, int refresh, int options)
174{
175 struct cache_entry *ce;
176 ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
177 if (!ce)
178 return error("addinfo_cache failed for path '%s'", path);
179 return add_cache_entry(ce, options);
180}
181/*
183 * This is a global variable which is used in a number of places but
184 * only written to in the 'merge' function.
185 *
186 * index_only == 1 => Don't leave any non-stage 0 entries in the cache and
187 * don't update the working directory.
188 * 0 => Leave unmerged entries in the cache and update
189 * the working directory.
190 */
191static int index_only = 0;
192static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree)
194{
195 parse_tree(tree);
196 init_tree_desc(desc, tree->buffer, tree->size);
197}
198static int git_merge_trees(int index_only,
200 struct tree *common,
201 struct tree *head,
202 struct tree *merge)
203{
204 int rc;
205 struct tree_desc t[3];
206 struct unpack_trees_options opts;
207 memset(&opts, 0, sizeof(opts));
209 if (index_only)
210 opts.index_only = 1;
211 else
212 opts.update = 1;
213 opts.merge = 1;
214 opts.head_idx = 2;
215 opts.fn = threeway_merge;
216 init_tree_desc_from_tree(t+0, common);
218 init_tree_desc_from_tree(t+1, head);
219 init_tree_desc_from_tree(t+2, merge);
220 rc = unpack_trees(3, t, &opts);
222 cache_tree_free(&active_cache_tree);
223 return rc;
224}
225static int unmerged_index(void)
227{
228 int i;
229 for (i = 0; i < active_nr; i++) {
230 struct cache_entry *ce = active_cache[i];
231 if (ce_stage(ce))
232 return 1;
233 }
234 return 0;
235}
236struct tree *write_tree_from_memory(void)
238{
239 struct tree *result = NULL;
240 if (unmerged_index()) {
242 int i;
243 output(0, "There are unmerged index entries:");
244 for (i = 0; i < active_nr; i++) {
245 struct cache_entry *ce = active_cache[i];
246 if (ce_stage(ce))
247 output(0, "%d %.*s", ce_stage(ce), ce_namelen(ce), ce->name);
248 }
249 return NULL;
250 }
251 if (!active_cache_tree)
253 active_cache_tree = cache_tree();
254 if (!cache_tree_fully_valid(active_cache_tree) &&
256 cache_tree_update(active_cache_tree,
257 active_cache, active_nr, 0, 0) < 0)
258 die("error building trees");
259 result = lookup_tree(active_cache_tree->sha1);
261 return result;
263}
264static int save_files_dirs(const unsigned char *sha1,
266 const char *base, int baselen, const char *path,
267 unsigned int mode, int stage)
268{
269 int len = strlen(path);
270 char *newpath = xmalloc(baselen + len + 1);
271 memcpy(newpath, base, baselen);
272 memcpy(newpath + baselen, path, len);
273 newpath[baselen + len] = '\0';
274 if (S_ISDIR(mode))
276 path_list_insert(newpath, ¤t_directory_set);
277 else
278 path_list_insert(newpath, ¤t_file_set);
279 free(newpath);
280 return READ_TREE_RECURSIVE;
282}
283static int get_files_dirs(struct tree *tree)
285{
286 int n;
287 if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs) != 0)
288 return 0;
289 n = current_file_set.nr + current_directory_set.nr;
290 return n;
291}
292/*
294 * Returns an index_entry instance which doesn't have to correspond to
295 * a real cache entry in Git's index.
296 */
297static struct stage_data *insert_stage_data(const char *path,
298 struct tree *o, struct tree *a, struct tree *b,
299 struct path_list *entries)
300{
301 struct path_list_item *item;
302 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
303 get_tree_entry(o->object.sha1, path,
304 e->stages[1].sha, &e->stages[1].mode);
305 get_tree_entry(a->object.sha1, path,
306 e->stages[2].sha, &e->stages[2].mode);
307 get_tree_entry(b->object.sha1, path,
308 e->stages[3].sha, &e->stages[3].mode);
309 item = path_list_insert(path, entries);
310 item->util = e;
311 return e;
312}
313/*
315 * Create a dictionary mapping file names to stage_data objects. The
316 * dictionary contains one entry for every path with a non-zero stage entry.
317 */
318static struct path_list *get_unmerged(void)
319{
320 struct path_list *unmerged = xcalloc(1, sizeof(struct path_list));
321 int i;
322 unmerged->strdup_paths = 1;
324 for (i = 0; i < active_nr; i++) {
326 struct path_list_item *item;
327 struct stage_data *e;
328 struct cache_entry *ce = active_cache[i];
329 if (!ce_stage(ce))
330 continue;
331 item = path_list_lookup(ce->name, unmerged);
333 if (!item) {
334 item = path_list_insert(ce->name, unmerged);
335 item->util = xcalloc(1, sizeof(struct stage_data));
336 }
337 e = item->util;
338 e->stages[ce_stage(ce)].mode = ce->ce_mode;
339 hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
340 }
341 return unmerged;
343}
344struct rename
346{
347 struct diff_filepair *pair;
348 struct stage_data *src_entry;
349 struct stage_data *dst_entry;
350 unsigned processed:1;
351};
352/*
354 * Get information of all renames which occurred between 'o_tree' and
355 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
356 * 'b_tree') to be able to associate the correct cache entries with
357 * the rename information. 'tree' is always equal to either a_tree or b_tree.
358 */
359static struct path_list *get_renames(struct tree *tree,
360 struct tree *o_tree,
361 struct tree *a_tree,
362 struct tree *b_tree,
363 struct path_list *entries)
364{
365 int i;
366 struct path_list *renames;
367 struct diff_options opts;
368 renames = xcalloc(1, sizeof(struct path_list));
370 diff_setup(&opts);
371 DIFF_OPT_SET(&opts, RECURSIVE);
372 opts.detect_rename = DIFF_DETECT_RENAME;
373 opts.rename_limit = rename_limit;
374 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
375 if (diff_setup_done(&opts) < 0)
376 die("diff setup failed");
377 diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
378 diffcore_std(&opts);
379 for (i = 0; i < diff_queued_diff.nr; ++i) {
380 struct path_list_item *item;
381 struct rename *re;
382 struct diff_filepair *pair = diff_queued_diff.queue[i];
383 if (pair->status != 'R') {
384 diff_free_filepair(pair);
385 continue;
386 }
387 re = xmalloc(sizeof(*re));
388 re->processed = 0;
389 re->pair = pair;
390 item = path_list_lookup(re->pair->one->path, entries);
391 if (!item)
392 re->src_entry = insert_stage_data(re->pair->one->path,
393 o_tree, a_tree, b_tree, entries);
394 else
395 re->src_entry = item->util;
396 item = path_list_lookup(re->pair->two->path, entries);
398 if (!item)
399 re->dst_entry = insert_stage_data(re->pair->two->path,
400 o_tree, a_tree, b_tree, entries);
401 else
402 re->dst_entry = item->util;
403 item = path_list_insert(pair->one->path, renames);
404 item->util = re;
405 }
406 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
407 diff_queued_diff.nr = 0;
408 diff_flush(&opts);
409 return renames;
410}
411static int update_stages(const char *path, struct diff_filespec *o,
413 struct diff_filespec *a, struct diff_filespec *b,
414 int clear)
415{
416 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
417 if (clear)
418 if (remove_file_from_cache(path))
419 return -1;
420 if (o)
421 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
422 return -1;
423 if (a)
424 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
425 return -1;
426 if (b)
427 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
428 return -1;
429 return 0;
430}
431static int remove_path(const char *name)
433{
434 int ret;
435 char *slash, *dirs;
436 ret = unlink(name);
438 if (ret)
439 return ret;
440 dirs = xstrdup(name);
441 while ((slash = strrchr(name, '/'))) {
442 *slash = '\0';
443 if (rmdir(name) != 0)
444 break;
445 }
446 free(dirs);
447 return ret;
448}
449static int remove_file(int clean, const char *path, int no_wd)
451{
452 int update_cache = index_only || clean;
453 int update_working_directory = !index_only && !no_wd;
454 if (update_cache) {
456 if (remove_file_from_cache(path))
457 return -1;
458 }
459 if (update_working_directory) {
460 unlink(path);
461 if (errno != ENOENT || errno != EISDIR)
462 return -1;
463 remove_path(path);
464 }
465 return 0;
466}
467static char *unique_path(const char *path, const char *branch)
469{
470 char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
471 int suffix = 0;
472 struct stat st;
473 char *p = newpath + strlen(path);
474 strcpy(newpath, path);
475 *(p++) = '~';
476 strcpy(p, branch);
477 for (; *p; ++p)
478 if ('/' == *p)
479 *p = '_';
480 while (path_list_has_path(¤t_file_set, newpath) ||
481 path_list_has_path(¤t_directory_set, newpath) ||
482 lstat(newpath, &st) == 0)
483 sprintf(p, "_%d", suffix++);
484 path_list_insert(newpath, ¤t_file_set);
486 return newpath;
487}
488static int mkdir_p(const char *path, unsigned long mode)
490{
491 /* path points to cache entries, so xstrdup before messing with it */
492 char *buf = xstrdup(path);
493 int result = safe_create_leading_directories(buf);
494 free(buf);
495 return result;
496}
497static void flush_buffer(int fd, const char *buf, unsigned long size)
499{
500 while (size > 0) {
501 long ret = write_in_full(fd, buf, size);
502 if (ret < 0) {
503 /* Ignore epipe */
504 if (errno == EPIPE)
505 break;
506 die("merge-recursive: %s", strerror(errno));
507 } else if (!ret) {
508 die("merge-recursive: disk full?");
509 }
510 size -= ret;
511 buf += ret;
512 }
513}
514static int make_room_for_path(const char *path)
516{
517 int status;
518 const char *msg = "failed to create path '%s'%s";
519 status = mkdir_p(path, 0777);
521 if (status) {
522 if (status == -3) {
523 /* something else exists */
524 error(msg, path, ": perhaps a D/F conflict?");
525 return -1;
526 }
527 die(msg, path, "");
528 }
529 /* Successful unlink is good.. */
531 if (!unlink(path))
532 return 0;
533 /* .. and so is no existing file */
534 if (errno == ENOENT)
535 return 0;
536 /* .. but not some other error (who really cares what?) */
537 return error(msg, path, ": perhaps a D/F conflict?");
538}
539static void update_file_flags(const unsigned char *sha,
541 unsigned mode,
542 const char *path,
543 int update_cache,
544 int update_wd)
545{
546 if (index_only)
547 update_wd = 0;
548 if (update_wd) {
550 enum object_type type;
551 void *buf;
552 unsigned long size;
553 if (S_ISGITLINK(mode))
555 die("cannot read object %s '%s': It is a submodule!",
556 sha1_to_hex(sha), path);
557 buf = read_sha1_file(sha, &type, &size);
559 if (!buf)
560 die("cannot read object %s '%s'", sha1_to_hex(sha), path);
561 if (type != OBJ_BLOB)
562 die("blob expected for %s '%s'", sha1_to_hex(sha), path);
563 if (make_room_for_path(path) < 0) {
565 update_wd = 0;
566 goto update_index;
567 }
568 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
569 int fd;
570 if (mode & 0100)
571 mode = 0777;
572 else
573 mode = 0666;
574 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
575 if (fd < 0)
576 die("failed to open %s: %s", path, strerror(errno));
577 flush_buffer(fd, buf, size);
578 close(fd);
579 } else if (S_ISLNK(mode)) {
580 char *lnk = xmemdupz(buf, size);
581 mkdir_p(path, 0777);
582 unlink(path);
583 symlink(lnk, path);
584 free(lnk);
585 } else
586 die("do not know what to do with %06o %s '%s'",
587 mode, sha1_to_hex(sha), path);
588 }
589 update_index:
590 if (update_cache)
591 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
592}
593static void update_file(int clean,
595 const unsigned char *sha,
596 unsigned mode,
597 const char *path)
598{
599 update_file_flags(sha, mode, path, index_only || clean, !index_only);
600}
601/* Low level file merging, update and removal */
603struct merge_file_info
605{
606 unsigned char sha[20];
607 unsigned mode;
608 unsigned clean:1,
609 merge:1;
610};
611static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
613{
614 unsigned long size;
615 enum object_type type;
616 if (!hashcmp(sha1, null_sha1)) {
618 mm->ptr = xstrdup("");
619 mm->size = 0;
620 return;
621 }
622 mm->ptr = read_sha1_file(sha1, &type, &size);
624 if (!mm->ptr || type != OBJ_BLOB)
625 die("unable to read blob object %s", sha1_to_hex(sha1));
626 mm->size = size;
627}
628/*
630 * Customizable low-level merge drivers support.
631 */
632struct ll_merge_driver;
634typedef int (*ll_merge_fn)(const struct ll_merge_driver *,
635 const char *path,
636 mmfile_t *orig,
637 mmfile_t *src1, const char *name1,
638 mmfile_t *src2, const char *name2,
639 mmbuffer_t *result);
640struct ll_merge_driver {
642 const char *name;
643 const char *description;
644 ll_merge_fn fn;
645 const char *recursive;
646 struct ll_merge_driver *next;
647 char *cmdline;
648};
649/*
651 * Built-in low-levels
652 */
653static int ll_binary_merge(const struct ll_merge_driver *drv_unused,
654 const char *path_unused,
655 mmfile_t *orig,
656 mmfile_t *src1, const char *name1,
657 mmfile_t *src2, const char *name2,
658 mmbuffer_t *result)
659{
660 /*
661 * The tentative merge result is "ours" for the final round,
662 * or common ancestor for an internal merge. Still return
663 * "conflicted merge" status.
664 */
665 mmfile_t *stolen = index_only ? orig : src1;
666 result->ptr = stolen->ptr;
668 result->size = stolen->size;
669 stolen->ptr = NULL;
670 return 1;
671}
672static int ll_xdl_merge(const struct ll_merge_driver *drv_unused,
674 const char *path_unused,
675 mmfile_t *orig,
676 mmfile_t *src1, const char *name1,
677 mmfile_t *src2, const char *name2,
678 mmbuffer_t *result)
679{
680 xpparam_t xpp;
681 if (buffer_is_binary(orig->ptr, orig->size) ||
683 buffer_is_binary(src1->ptr, src1->size) ||
684 buffer_is_binary(src2->ptr, src2->size)) {
685 warning("Cannot merge binary files: %s vs. %s\n",
686 name1, name2);
687 return ll_binary_merge(drv_unused, path_unused,
688 orig, src1, name1,
689 src2, name2,
690 result);
691 }
692 memset(&xpp, 0, sizeof(xpp));
694 return xdl_merge(orig,
695 src1, name1,
696 src2, name2,
697 &xpp, XDL_MERGE_ZEALOUS,
698 result);
699}
700static int ll_union_merge(const struct ll_merge_driver *drv_unused,
702 const char *path_unused,
703 mmfile_t *orig,
704 mmfile_t *src1, const char *name1,
705 mmfile_t *src2, const char *name2,
706 mmbuffer_t *result)
707{
708 char *src, *dst;
709 long size;
710 const int marker_size = 7;
711 int status = ll_xdl_merge(drv_unused, path_unused,
713 orig, src1, NULL, src2, NULL, result);
714 if (status <= 0)
715 return status;
716 size = result->size;
717 src = dst = result->ptr;
718 while (size) {
719 char ch;
720 if ((marker_size < size) &&
721 (*src == '<' || *src == '=' || *src == '>')) {
722 int i;
723 ch = *src;
724 for (i = 0; i < marker_size; i++)
725 if (src[i] != ch)
726 goto not_a_marker;
727 if (src[marker_size] != '\n')
728 goto not_a_marker;
729 src += marker_size + 1;
730 size -= marker_size + 1;
731 continue;
732 }
733 not_a_marker:
734 do {
735 ch = *src++;
736 *dst++ = ch;
737 size--;
738 } while (ch != '\n' && size);
739 }
740 result->size = dst - result->ptr;
741 return 0;
742}
743#define LL_BINARY_MERGE 0
745#define LL_TEXT_MERGE 1
746#define LL_UNION_MERGE 2
747static struct ll_merge_driver ll_merge_drv[] = {
748 { "binary", "built-in binary merge", ll_binary_merge },
749 { "text", "built-in 3-way text merge", ll_xdl_merge },
750 { "union", "built-in union merge", ll_union_merge },
751};
752static void create_temp(mmfile_t *src, char *path)
754{
755 int fd;
756 strcpy(path, ".merge_file_XXXXXX");
758 fd = xmkstemp(path);
759 if (write_in_full(fd, src->ptr, src->size) != src->size)
760 die("unable to write temp-file");
761 close(fd);
762}
763/*
765 * User defined low-level merge driver support.
766 */
767static int ll_ext_merge(const struct ll_merge_driver *fn,
768 const char *path,
769 mmfile_t *orig,
770 mmfile_t *src1, const char *name1,
771 mmfile_t *src2, const char *name2,
772 mmbuffer_t *result)
773{
774 char temp[3][50];
775 char cmdbuf[2048];
776 struct interp table[] = {
777 { "%O" },
778 { "%A" },
779 { "%B" },
780 };
781 struct child_process child;
782 const char *args[20];
783 int status, fd, i;
784 struct stat st;
785 if (fn->cmdline == NULL)
787 die("custom merge driver %s lacks command line.", fn->name);
788 result->ptr = NULL;
790 result->size = 0;
791 create_temp(orig, temp[0]);
792 create_temp(src1, temp[1]);
793 create_temp(src2, temp[2]);
794 interp_set_entry(table, 0, temp[0]);
796 interp_set_entry(table, 1, temp[1]);
797 interp_set_entry(table, 2, temp[2]);
798 output(1, "merging %s using %s", path,
800 fn->description ? fn->description : fn->name);
801 interpolate(cmdbuf, sizeof(cmdbuf), fn->cmdline, table, 3);
803 memset(&child, 0, sizeof(child));
805 child.argv = args;
806 args[0] = "sh";
807 args[1] = "-c";
808 args[2] = cmdbuf;
809 args[3] = NULL;
810 status = run_command(&child);
812 if (status < -ERR_RUN_COMMAND_FORK)
813 ; /* failure in run-command */
814 else
815 status = -status;
816 fd = open(temp[1], O_RDONLY);
817 if (fd < 0)
818 goto bad;
819 if (fstat(fd, &st))
820 goto close_bad;
821 result->size = st.st_size;
822 result->ptr = xmalloc(result->size + 1);
823 if (read_in_full(fd, result->ptr, result->size) != result->size) {
824 free(result->ptr);
825 result->ptr = NULL;
826 result->size = 0;
827 }
828 close_bad:
829 close(fd);
830 bad:
831 for (i = 0; i < 3; i++)
832 unlink(temp[i]);
833 return status;
834}
835/*
837 * merge.default and merge.driver configuration items
838 */
839static struct ll_merge_driver *ll_user_merge, **ll_user_merge_tail;
840static const char *default_ll_merge;
841static int read_merge_config(const char *var, const char *value)
843{
844 struct ll_merge_driver *fn;
845 const char *ep, *name;
846 int namelen;
847 if (!strcmp(var, "merge.default")) {
849 if (value)
850 default_ll_merge = strdup(value);
851 return 0;
852 }
853 /*
855 * We are not interested in anything but "merge.<name>.variable";
856 * especially, we do not want to look at variables such as
857 * "merge.summary", "merge.tool", and "merge.verbosity".
858 */
859 if (prefixcmp(var, "merge.") || (ep = strrchr(var, '.')) == var + 5)
860 return 0;
861 /*
863 * Find existing one as we might be processing merge.<name>.var2
864 * after seeing merge.<name>.var1.
865 */
866 name = var + 6;
867 namelen = ep - name;
868 for (fn = ll_user_merge; fn; fn = fn->next)
869 if (!strncmp(fn->name, name, namelen) && !fn->name[namelen])
870 break;
871 if (!fn) {
872 fn = xcalloc(1, sizeof(struct ll_merge_driver));
873 fn->name = xmemdupz(name, namelen);
874 fn->fn = ll_ext_merge;
875 *ll_user_merge_tail = fn;
876 ll_user_merge_tail = &(fn->next);
877 }
878 ep++;
880 if (!strcmp("name", ep)) {
882 if (!value)
883 return error("%s: lacks value", var);
884 fn->description = strdup(value);
885 return 0;
886 }
887 if (!strcmp("driver", ep)) {
889 if (!value)
890 return error("%s: lacks value", var);
891 /*
892 * merge.<name>.driver specifies the command line:
893 *
894 * command-line
895 *
896 * The command-line will be interpolated with the following
897 * tokens and is given to the shell:
898 *
899 * %O - temporary file name for the merge base.
900 * %A - temporary file name for our version.
901 * %B - temporary file name for the other branches' version.
902 *
903 * The external merge driver should write the results in the
904 * file named by %A, and signal that it has done with zero exit
905 * status.
906 */
907 fn->cmdline = strdup(value);
908 return 0;
909 }
910 if (!strcmp("recursive", ep)) {
912 if (!value)
913 return error("%s: lacks value", var);
914 fn->recursive = strdup(value);
915 return 0;
916 }
917 return 0;
919}
920static void initialize_ll_merge(void)
922{
923 if (ll_user_merge_tail)
924 return;
925 ll_user_merge_tail = &ll_user_merge;
926 git_config(read_merge_config);
927}
928static const struct ll_merge_driver *find_ll_merge_driver(const char *merge_attr)
930{
931 struct ll_merge_driver *fn;
932 const char *name;
933 int i;
934 initialize_ll_merge();
936 if (ATTR_TRUE(merge_attr))
938 return &ll_merge_drv[LL_TEXT_MERGE];
939 else if (ATTR_FALSE(merge_attr))
940 return &ll_merge_drv[LL_BINARY_MERGE];
941 else if (ATTR_UNSET(merge_attr)) {
942 if (!default_ll_merge)
943 return &ll_merge_drv[LL_TEXT_MERGE];
944 else
945 name = default_ll_merge;
946 }
947 else
948 name = merge_attr;
949 for (fn = ll_user_merge; fn; fn = fn->next)
951 if (!strcmp(fn->name, name))
952 return fn;
953 for (i = 0; i < ARRAY_SIZE(ll_merge_drv); i++)
955 if (!strcmp(ll_merge_drv[i].name, name))
956 return &ll_merge_drv[i];
957 /* default to the 3-way */
959 return &ll_merge_drv[LL_TEXT_MERGE];
960}
961static const char *git_path_check_merge(const char *path)
963{
964 static struct git_attr_check attr_merge_check;
965 if (!attr_merge_check.attr)
967 attr_merge_check.attr = git_attr("merge", 5);
968 if (git_checkattr(path, 1, &attr_merge_check))
970 return NULL;
971 return attr_merge_check.value;
972}
973static int ll_merge(mmbuffer_t *result_buf,
975 struct diff_filespec *o,
976 struct diff_filespec *a,
977 struct diff_filespec *b,
978 const char *branch1,
979 const char *branch2)
980{
981 mmfile_t orig, src1, src2;
982 char *name1, *name2;
983 int merge_status;
984 const char *ll_driver_name;
985 const struct ll_merge_driver *driver;
986 name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
988 name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
989 fill_mm(o->sha1, &orig);
991 fill_mm(a->sha1, &src1);
992 fill_mm(b->sha1, &src2);
993 ll_driver_name = git_path_check_merge(a->path);
995 driver = find_ll_merge_driver(ll_driver_name);
996 if (index_only && driver->recursive)
998 driver = find_ll_merge_driver(driver->recursive);
999 merge_status = driver->fn(driver, a->path,
1000 &orig, &src1, name1, &src2, name2,
1001 result_buf);
1002 free(name1);
1004 free(name2);
1005 free(orig.ptr);
1006 free(src1.ptr);
1007 free(src2.ptr);
1008 return merge_status;
1009}
1010static struct merge_file_info merge_file(struct diff_filespec *o,
1012 struct diff_filespec *a, struct diff_filespec *b,
1013 const char *branch1, const char *branch2)
1014{
1015 struct merge_file_info result;
1016 result.merge = 0;
1017 result.clean = 1;
1018 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
1020 result.clean = 0;
1021 if (S_ISREG(a->mode)) {
1022 result.mode = a->mode;
1023 hashcpy(result.sha, a->sha1);
1024 } else {
1025 result.mode = b->mode;
1026 hashcpy(result.sha, b->sha1);
1027 }
1028 } else {
1029 if (!sha_eq(a->sha1, o->sha1) && !sha_eq(b->sha1, o->sha1))
1030 result.merge = 1;
1031 result.mode = a->mode == o->mode ? b->mode: a->mode;
1033 if (sha_eq(a->sha1, o->sha1))
1035 hashcpy(result.sha, b->sha1);
1036 else if (sha_eq(b->sha1, o->sha1))
1037 hashcpy(result.sha, a->sha1);
1038 else if (S_ISREG(a->mode)) {
1039 mmbuffer_t result_buf;
1040 int merge_status;
1041 merge_status = ll_merge(&result_buf, o, a, b,
1043 branch1, branch2);
1044 if ((merge_status < 0) || !result_buf.ptr)
1046 die("Failed to execute internal merge");
1047 if (write_sha1_file(result_buf.ptr, result_buf.size,
1049 blob_type, result.sha))
1050 die("Unable to add %s to database",
1051 a->path);
1052 free(result_buf.ptr);
1054 result.clean = (merge_status == 0);
1055 } else if (S_ISGITLINK(a->mode)) {
1056 result.clean = 0;
1057 hashcpy(result.sha, a->sha1);
1058 } else if (S_ISLNK(a->mode)) {
1059 hashcpy(result.sha, a->sha1);
1060 if (!sha_eq(a->sha1, b->sha1))
1062 result.clean = 0;
1063 } else {
1064 die("unsupported object type in the tree");
1065 }
1066 }
1067 return result;
1069}
1070static void conflict_rename_rename(struct rename *ren1,
1072 const char *branch1,
1073 struct rename *ren2,
1074 const char *branch2)
1075{
1076 char *del[2];
1077 int delp = 0;
1078 const char *ren1_dst = ren1->pair->two->path;
1079 const char *ren2_dst = ren2->pair->two->path;
1080 const char *dst_name1 = ren1_dst;
1081 const char *dst_name2 = ren2_dst;
1082 if (path_list_has_path(¤t_directory_set, ren1_dst)) {
1083 dst_name1 = del[delp++] = unique_path(ren1_dst, branch1);
1084 output(1, "%s is a directory in %s added as %s instead",
1085 ren1_dst, branch2, dst_name1);
1086 remove_file(0, ren1_dst, 0);
1087 }
1088 if (path_list_has_path(¤t_directory_set, ren2_dst)) {
1089 dst_name2 = del[delp++] = unique_path(ren2_dst, branch2);
1090 output(1, "%s is a directory in %s added as %s instead",
1091 ren2_dst, branch1, dst_name2);
1092 remove_file(0, ren2_dst, 0);
1093 }
1094 if (index_only) {
1095 remove_file_from_cache(dst_name1);
1096 remove_file_from_cache(dst_name2);
1097 /*
1098 * Uncomment to leave the conflicting names in the resulting tree
1099 *
1100 * update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, dst_name1);
1101 * update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, dst_name2);
1102 */
1103 } else {
1104 update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
1105 update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
1106 }
1107 while (delp--)
1108 free(del[delp]);
1109}
1110static void conflict_rename_dir(struct rename *ren1,
1112 const char *branch1)
1113{
1114 char *new_path = unique_path(ren1->pair->two->path, branch1);
1115 output(1, "Renamed %s to %s instead", ren1->pair->one->path, new_path);
1116 remove_file(0, ren1->pair->two->path, 0);
1117 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
1118 free(new_path);
1119}
1120static void conflict_rename_rename_2(struct rename *ren1,
1122 const char *branch1,
1123 struct rename *ren2,
1124 const char *branch2)
1125{
1126 char *new_path1 = unique_path(ren1->pair->two->path, branch1);
1127 char *new_path2 = unique_path(ren2->pair->two->path, branch2);
1128 output(1, "Renamed %s to %s and %s to %s instead",
1129 ren1->pair->one->path, new_path1,
1130 ren2->pair->one->path, new_path2);
1131 remove_file(0, ren1->pair->two->path, 0);
1132 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
1133 update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
1134 free(new_path2);
1135 free(new_path1);
1136}
1137static int process_renames(struct path_list *a_renames,
1139 struct path_list *b_renames,
1140 const char *a_branch,
1141 const char *b_branch)
1142{
1143 int clean_merge = 1, i, j;
1144 struct path_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
1145 const struct rename *sre;
1146 for (i = 0; i < a_renames->nr; i++) {
1148 sre = a_renames->items[i].util;
1149 path_list_insert(sre->pair->two->path, &a_by_dst)->util
1150 = sre->dst_entry;
1151 }
1152 for (i = 0; i < b_renames->nr; i++) {
1153 sre = b_renames->items[i].util;
1154 path_list_insert(sre->pair->two->path, &b_by_dst)->util
1155 = sre->dst_entry;
1156 }
1157 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
1159 int compare;
1160 char *src;
1161 struct path_list *renames1, *renames2, *renames2Dst;
1162 struct rename *ren1 = NULL, *ren2 = NULL;
1163 const char *branch1, *branch2;
1164 const char *ren1_src, *ren1_dst;
1165 if (i >= a_renames->nr) {
1167 compare = 1;
1168 ren2 = b_renames->items[j++].util;
1169 } else if (j >= b_renames->nr) {
1170 compare = -1;
1171 ren1 = a_renames->items[i++].util;
1172 } else {
1173 compare = strcmp(a_renames->items[i].path,
1174 b_renames->items[j].path);
1175 if (compare <= 0)
1176 ren1 = a_renames->items[i++].util;
1177 if (compare >= 0)
1178 ren2 = b_renames->items[j++].util;
1179 }
1180 /* TODO: refactor, so that 1/2 are not needed */
1182 if (ren1) {
1183 renames1 = a_renames;
1184 renames2 = b_renames;
1185 renames2Dst = &b_by_dst;
1186 branch1 = a_branch;
1187 branch2 = b_branch;
1188 } else {
1189 struct rename *tmp;
1190 renames1 = b_renames;
1191 renames2 = a_renames;
1192 renames2Dst = &a_by_dst;
1193 branch1 = b_branch;
1194 branch2 = a_branch;
1195 tmp = ren2;
1196 ren2 = ren1;
1197 ren1 = tmp;
1198 }
1199 src = ren1->pair->one->path;
1200 ren1->dst_entry->processed = 1;
1202 ren1->src_entry->processed = 1;
1203 if (ren1->processed)
1205 continue;
1206 ren1->processed = 1;
1207 ren1_src = ren1->pair->one->path;
1209 ren1_dst = ren1->pair->two->path;
1210 if (ren2) {
1212 const char *ren2_src = ren2->pair->one->path;
1213 const char *ren2_dst = ren2->pair->two->path;
1214 /* Renamed in 1 and renamed in 2 */
1215 if (strcmp(ren1_src, ren2_src) != 0)
1216 die("ren1.src != ren2.src");
1217 ren2->dst_entry->processed = 1;
1218 ren2->processed = 1;
1219 if (strcmp(ren1_dst, ren2_dst) != 0) {
1220 clean_merge = 0;
1221 output(1, "CONFLICT (rename/rename): "
1222 "Rename \"%s\"->\"%s\" in branch \"%s\" "
1223 "rename \"%s\"->\"%s\" in \"%s\"%s",
1224 src, ren1_dst, branch1,
1225 src, ren2_dst, branch2,
1226 index_only ? " (left unresolved)": "");
1227 if (index_only) {
1228 remove_file_from_cache(src);
1229 update_file(0, ren1->pair->one->sha1,
1230 ren1->pair->one->mode, src);
1231 }
1232 conflict_rename_rename(ren1, branch1, ren2, branch2);
1233 } else {
1234 struct merge_file_info mfi;
1235 remove_file(1, ren1_src, 1);
1236 mfi = merge_file(ren1->pair->one,
1237 ren1->pair->two,
1238 ren2->pair->two,
1239 branch1,
1240 branch2);
1241 if (mfi.merge || !mfi.clean)
1242 output(1, "Renamed %s->%s", src, ren1_dst);
1243 if (mfi.merge)
1245 output(2, "Auto-merged %s", ren1_dst);
1246 if (!mfi.clean) {
1248 output(1, "CONFLICT (content): merge conflict in %s",
1249 ren1_dst);
1250 clean_merge = 0;
1251 if (!index_only)
1253 update_stages(ren1_dst,
1254 ren1->pair->one,
1255 ren1->pair->two,
1256 ren2->pair->two,
1257 1 /* clear */);
1258 }
1259 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
1260 }
1261 } else {
1262 /* Renamed in 1, maybe changed in 2 */
1263 struct path_list_item *item;
1264 /* we only use sha1 and mode of these */
1265 struct diff_filespec src_other, dst_other;
1266 int try_merge, stage = a_renames == renames1 ? 3: 2;
1267 remove_file(1, ren1_src, index_only || stage == 3);
1269 hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
1271 src_other.mode = ren1->src_entry->stages[stage].mode;
1272 hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha);
1273 dst_other.mode = ren1->dst_entry->stages[stage].mode;
1274 try_merge = 0;
1276 if (path_list_has_path(¤t_directory_set, ren1_dst)) {
1278 clean_merge = 0;
1279 output(1, "CONFLICT (rename/directory): Renamed %s->%s in %s "
1280 " directory %s added in %s",
1281 ren1_src, ren1_dst, branch1,
1282 ren1_dst, branch2);
1283 conflict_rename_dir(ren1, branch1);
1284 } else if (sha_eq(src_other.sha1, null_sha1)) {
1285 clean_merge = 0;
1286 output(1, "CONFLICT (rename/delete): Renamed %s->%s in %s "
1287 "and deleted in %s",
1288 ren1_src, ren1_dst, branch1,
1289 branch2);
1290 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
1291 } else if (!sha_eq(dst_other.sha1, null_sha1)) {
1292 const char *new_path;
1293 clean_merge = 0;
1294 try_merge = 1;
1295 output(1, "CONFLICT (rename/add): Renamed %s->%s in %s. "
1296 "%s added in %s",
1297 ren1_src, ren1_dst, branch1,
1298 ren1_dst, branch2);
1299 new_path = unique_path(ren1_dst, branch2);
1300 output(1, "Added as %s instead", new_path);
1301 update_file(0, dst_other.sha1, dst_other.mode, new_path);
1302 } else if ((item = path_list_lookup(ren1_dst, renames2Dst))) {
1303 ren2 = item->util;
1304 clean_merge = 0;
1305 ren2->processed = 1;
1306 output(1, "CONFLICT (rename/rename): Renamed %s->%s in %s. "
1307 "Renamed %s->%s in %s",
1308 ren1_src, ren1_dst, branch1,
1309 ren2->pair->one->path, ren2->pair->two->path, branch2);
1310 conflict_rename_rename_2(ren1, branch1, ren2, branch2);
1311 } else
1312 try_merge = 1;
1313 if (try_merge) {
1315 struct diff_filespec *o, *a, *b;
1316 struct merge_file_info mfi;
1317 src_other.path = (char *)ren1_src;
1318 o = ren1->pair->one;
1320 if (a_renames == renames1) {
1321 a = ren1->pair->two;
1322 b = &src_other;
1323 } else {
1324 b = ren1->pair->two;
1325 a = &src_other;
1326 }
1327 mfi = merge_file(o, a, b,
1328 a_branch, b_branch);
1329 if (mfi.clean &&
1331 sha_eq(mfi.sha, ren1->pair->two->sha1) &&
1332 mfi.mode == ren1->pair->two->mode)
1333 /*
1334 * This messaged is part of
1335 * t6022 test. If you change
1336 * it update the test too.
1337 */
1338 output(3, "Skipped %s (merged same as existing)", ren1_dst);
1339 else {
1340 if (mfi.merge || !mfi.clean)
1341 output(1, "Renamed %s => %s", ren1_src, ren1_dst);
1342 if (mfi.merge)
1343 output(2, "Auto-merged %s", ren1_dst);
1344 if (!mfi.clean) {
1345 output(1, "CONFLICT (rename/modify): Merge conflict in %s",
1346 ren1_dst);
1347 clean_merge = 0;
1348 if (!index_only)
1350 update_stages(ren1_dst,
1351 o, a, b, 1);
1352 }
1353 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
1354 }
1355 }
1356 }
1357 }
1358 path_list_clear(&a_by_dst, 0);
1359 path_list_clear(&b_by_dst, 0);
1360 return clean_merge;
1362}
1363static unsigned char *stage_sha(const unsigned char *sha, unsigned mode)
1365{
1366 return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha;
1367}
1368/* Per entry merge function */
1370static int process_entry(const char *path, struct stage_data *entry,
1371 const char *branch1,
1372 const char *branch2)
1373{
1374 /*
1375 printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
1376 print_index_entry("\tpath: ", entry);
1377 */
1378 int clean_merge = 1;
1379 unsigned o_mode = entry->stages[1].mode;
1380 unsigned a_mode = entry->stages[2].mode;
1381 unsigned b_mode = entry->stages[3].mode;
1382 unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
1383 unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
1384 unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
1385 if (o_sha && (!a_sha || !b_sha)) {
1387 /* Case A: Deleted in one */
1388 if ((!a_sha && !b_sha) ||
1389 (sha_eq(a_sha, o_sha) && !b_sha) ||
1390 (!a_sha && sha_eq(b_sha, o_sha))) {
1391 /* Deleted in both or deleted in one and
1392 * unchanged in the other */
1393 if (a_sha)
1394 output(2, "Removed %s", path);
1395 /* do not touch working file if it did not exist */
1396 remove_file(1, path, !a_sha);
1397 } else {
1398 /* Deleted in one and changed in the other */
1399 clean_merge = 0;
1400 if (!a_sha) {
1401 output(1, "CONFLICT (delete/modify): %s deleted in %s "
1402 "and modified in %s. Version %s of %s left in tree.",
1403 path, branch1,
1404 branch2, branch2, path);
1405 update_file(0, b_sha, b_mode, path);
1406 } else {
1407 output(1, "CONFLICT (delete/modify): %s deleted in %s "
1408 "and modified in %s. Version %s of %s left in tree.",
1409 path, branch2,
1410 branch1, branch1, path);
1411 update_file(0, a_sha, a_mode, path);
1412 }
1413 }
1414 } else if ((!o_sha && a_sha && !b_sha) ||
1416 (!o_sha && !a_sha && b_sha)) {
1417 /* Case B: Added in one. */
1418 const char *add_branch;
1419 const char *other_branch;
1420 unsigned mode;
1421 const unsigned char *sha;
1422 const char *conf;
1423 if (a_sha) {
1425 add_branch = branch1;
1426 other_branch = branch2;
1427 mode = a_mode;
1428 sha = a_sha;
1429 conf = "file/directory";
1430 } else {
1431 add_branch = branch2;
1432 other_branch = branch1;
1433 mode = b_mode;
1434 sha = b_sha;
1435 conf = "directory/file";
1436 }
1437 if (path_list_has_path(¤t_directory_set, path)) {
1438 const char *new_path = unique_path(path, add_branch);
1439 clean_merge = 0;
1440 output(1, "CONFLICT (%s): There is a directory with name %s in %s. "
1441 "Added %s as %s",
1442 conf, path, other_branch, path, new_path);
1443 remove_file(0, path, 0);
1444 update_file(0, sha, mode, new_path);
1445 } else {
1446 output(2, "Added %s", path);
1447 update_file(1, sha, mode, path);
1448 }
1449 } else if (a_sha && b_sha) {
1450 /* Case C: Added in both (check for same permissions) and */
1451 /* case D: Modified in both, but differently. */
1452 const char *reason = "content";
1453 struct merge_file_info mfi;
1454 struct diff_filespec o, a, b;
1455 if (!o_sha) {
1457 reason = "add/add";
1458 o_sha = (unsigned char *)null_sha1;
1459 }
1460 output(2, "Auto-merged %s", path);
1461 o.path = a.path = b.path = (char *)path;
1462 hashcpy(o.sha1, o_sha);
1463 o.mode = o_mode;
1464 hashcpy(a.sha1, a_sha);
1465 a.mode = a_mode;
1466 hashcpy(b.sha1, b_sha);
1467 b.mode = b_mode;
1468 mfi = merge_file(&o, &a, &b,
1470 branch1, branch2);
1471 clean_merge = mfi.clean;
1473 if (mfi.clean)
1474 update_file(1, mfi.sha, mfi.mode, path);
1475 else if (S_ISGITLINK(mfi.mode))
1476 output(1, "CONFLICT (submodule): Merge conflict in %s "
1477 "- needs %s", path, sha1_to_hex(b.sha1));
1478 else {
1479 output(1, "CONFLICT (%s): Merge conflict in %s",
1480 reason, path);
1481 if (index_only)
1483 update_file(0, mfi.sha, mfi.mode, path);
1484 else
1485 update_file_flags(mfi.sha, mfi.mode, path,
1486 0 /* update_cache */, 1 /* update_working_directory */);
1487 }
1488 } else if (!o_sha && !a_sha && !b_sha) {
1489 /*
1490 * this entry was deleted altogether. a_mode == 0 means
1491 * we had that path and want to actively remove it.
1492 */
1493 remove_file(1, path, !a_mode);
1494 } else
1495 die("Fatal merge failure, shouldn't happen.");
1496 return clean_merge;
1498}
1499int merge_trees(struct tree *head,
1501 struct tree *merge,
1502 struct tree *common,
1503 const char *branch1,
1504 const char *branch2,
1505 struct tree **result)
1506{
1507 int code, clean;
1508 if (subtree_merge) {
1510 merge = shift_tree_object(head, merge);
1511 common = shift_tree_object(head, common);
1512 }
1513 if (sha_eq(common->object.sha1, merge->object.sha1)) {
1515 output(0, "Already uptodate!");
1516 *result = head;
1517 return 1;
1518 }
1519 code = git_merge_trees(index_only, common, head, merge);
1521 if (code != 0)
1523 die("merging of trees %s and %s failed",
1524 sha1_to_hex(head->object.sha1),
1525 sha1_to_hex(merge->object.sha1));
1526 if (unmerged_index()) {
1528 struct path_list *entries, *re_head, *re_merge;
1529 int i;
1530 path_list_clear(¤t_file_set, 1);
1531 path_list_clear(¤t_directory_set, 1);
1532 get_files_dirs(head);
1533 get_files_dirs(merge);
1534 entries = get_unmerged();
1536 re_head = get_renames(head, common, head, merge, entries);
1537 re_merge = get_renames(merge, common, head, merge, entries);
1538 clean = process_renames(re_head, re_merge,
1539 branch1, branch2);
1540 for (i = 0; i < entries->nr; i++) {
1541 const char *path = entries->items[i].path;
1542 struct stage_data *e = entries->items[i].util;
1543 if (!e->processed
1544 && !process_entry(path, e, branch1, branch2))
1545 clean = 0;
1546 }
1547 path_list_clear(re_merge, 0);
1549 path_list_clear(re_head, 0);
1550 path_list_clear(entries, 1);
1551 }
1553 else
1554 clean = 1;
1555 if (index_only)
1557 *result = write_tree_from_memory();
1558 return clean;
1560}
1561static struct commit_list *reverse_commit_list(struct commit_list *list)
1563{
1564 struct commit_list *next = NULL, *current, *backup;
1565 for (current = list; current; current = backup) {
1566 backup = current->next;
1567 current->next = next;
1568 next = current;
1569 }
1570 return next;
1571}
1572/*
1574 * Merge the commits h1 and h2, return the resulting virtual
1575 * commit object and a flag indicating the cleanness of the merge.
1576 */
1577int merge_recursive(struct commit *h1,
1578 struct commit *h2,
1579 const char *branch1,
1580 const char *branch2,
1581 struct commit_list *ca,
1582 struct commit **result)
1583{
1584 struct commit_list *iter;
1585 struct commit *merged_common_ancestors;
1586 struct tree *mrtree = mrtree;
1587 int clean;
1588 if (show(4)) {
1590 output(4, "Merging:");
1591 output_commit_title(h1);
1592 output_commit_title(h2);
1593 }
1594 if (!ca) {
1596 ca = get_merge_bases(h1, h2, 1);
1597 ca = reverse_commit_list(ca);
1598 }
1599 if (show(5)) {
1601 output(5, "found %u common ancestor(s):", commit_list_count(ca));
1602 for (iter = ca; iter; iter = iter->next)
1603 output_commit_title(iter->item);
1604 }
1605 merged_common_ancestors = pop_commit(&ca);
1607 if (merged_common_ancestors == NULL) {
1608 /* if there is no common ancestor, make an empty tree */
1609 struct tree *tree = xcalloc(1, sizeof(struct tree));
1610 tree->object.parsed = 1;
1612 tree->object.type = OBJ_TREE;
1613 pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
1614 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1615 }
1616 for (iter = ca; iter; iter = iter->next) {
1618 call_depth++;
1619 /*
1620 * When the merge fails, the result contains files
1621 * with conflict markers. The cleanness flag is
1622 * ignored, it was never actually used, as result of
1623 * merge_trees has always overwritten it: the committed
1624 * "conflicts" were already resolved.
1625 */
1626 discard_cache();
1627 merge_recursive(merged_common_ancestors, iter->item,
1628 "Temporary merge branch 1",
1629 "Temporary merge branch 2",
1630 NULL,
1631 &merged_common_ancestors);
1632 call_depth--;
1633 if (!merged_common_ancestors)
1635 die("merge returned no commit");
1636 }
1637 discard_cache();
1639 if (!call_depth) {
1640 read_cache();
1641 index_only = 0;
1642 } else
1643 index_only = 1;
1644 clean = merge_trees(h1->tree, h2->tree, merged_common_ancestors->tree,
1646 branch1, branch2, &mrtree);
1647 if (index_only) {
1649 *result = make_virtual_commit(mrtree, "merged tree");
1650 commit_list_insert(h1, &(*result)->parents);
1651 commit_list_insert(h2, &(*result)->parents->next);
1652 }
1653 flush_output();
1654 return clean;
1655}
1656static const char *better_branch_name(const char *branch)
1658{
1659 static char githead_env[8 + 40 + 1];
1660 char *name;
1661 if (strlen(branch) != 40)
1663 return branch;
1664 sprintf(githead_env, "GITHEAD_%s", branch);
1665 name = getenv(githead_env);
1666 return name ? name : branch;
1667}
1668static struct commit *get_ref(const char *ref)
1670{
1671 unsigned char sha1[20];
1672 struct object *object;
1673 if (get_sha1(ref, sha1))
1675 die("Could not resolve ref '%s'", ref);
1676 object = deref_tag(parse_object(sha1), ref, strlen(ref));
1677 if (object->type == OBJ_TREE)
1678 return make_virtual_commit((struct tree*)object,
1679 better_branch_name(ref));
1680 if (object->type != OBJ_COMMIT)
1681 return NULL;
1682 if (parse_commit((struct commit *)object))
1683 die("Could not parse commit '%s'", sha1_to_hex(object->sha1));
1684 return (struct commit *)object;
1685}
1686static int merge_config(const char *var, const char *value)
1688{
1689 if (!strcasecmp(var, "merge.verbosity")) {
1690 verbosity = git_config_int(var, value);
1691 return 0;
1692 }
1693 if (!strcasecmp(var, "diff.renamelimit")) {
1694 rename_limit = git_config_int(var, value);
1695 return 0;
1696 }
1697 return git_default_config(var, value);
1698}
1699int cmd_merge_recursive(int argc, const char **argv, const char *prefix)
1701{
1702 static const char *bases[20];
1703 static unsigned bases_count = 0;
1704 int i, clean;
1705 const char *branch1, *branch2;
1706 struct commit *result, *h1, *h2;
1707 struct commit_list *ca = NULL;
1708 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1709 int index_fd;
1710 if (argv[0]) {
1712 int namelen = strlen(argv[0]);
1713 if (8 < namelen &&
1714 !strcmp(argv[0] + namelen - 8, "-subtree"))
1715 subtree_merge = 1;
1716 }
1717 git_config(merge_config);
1719 if (getenv("GIT_MERGE_VERBOSITY"))
1720 verbosity = strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
1721 if (argc < 4)
1723 die("Usage: %s <base>... -- <head> <remote> ...\n", argv[0]);
1724 for (i = 1; i < argc; ++i) {
1726 if (!strcmp(argv[i], "--"))
1727 break;
1728 if (bases_count < sizeof(bases)/sizeof(*bases))
1729 bases[bases_count++] = argv[i];
1730 }
1731 if (argc - i != 3) /* "--" "<head>" "<remote>" */
1732 die("Not handling anything other than two heads merge.");
1733 if (verbosity >= 5)
1734 buffer_output = 0;
1735 branch1 = argv[++i];
1737 branch2 = argv[++i];
1738 h1 = get_ref(branch1);
1740 h2 = get_ref(branch2);
1741 branch1 = better_branch_name(branch1);
1743 branch2 = better_branch_name(branch2);
1744 if (show(3))
1746 printf("Merging %s with %s\n", branch1, branch2);
1747 index_fd = hold_locked_index(lock, 1);
1749 for (i = 0; i < bases_count; i++) {
1751 struct commit *ancestor = get_ref(bases[i]);
1752 ca = commit_list_insert(ancestor, &ca);
1753 }
1754 clean = merge_recursive(h1, h2, branch1, branch2, ca, &result);
1755 if (active_cache_changed &&
1757 (write_cache(index_fd, active_cache, active_nr) ||
1758 commit_locked_index(lock)))
1759 die ("unable to write %s", get_index_file());
1760 return clean ? 0: 1;
1762}