merge-recursive.c

   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 <stdarg.h>
   7 #include <string.h>
   8 #include <assert.h>
   9 #include <sys/wait.h>
  10 #include <sys/types.h>
  11 #include <sys/stat.h>
  12 #include <time.h>
  13 #include "cache.h"
  14 #include "cache-tree.h"
  15 #include "commit.h"
  16 #include "blob.h"
  17 #include "tree-walk.h"
  18 #include "diff.h"
  19 #include "diffcore.h"
  20 #include "run-command.h"
  21 #include "tag.h"
  22 #include "unpack-trees.h"
  23 #include "path-list.h"
  24
  25 /*
  26  * A virtual commit has
  27  * - (const char *)commit->util set to the name, and
  28  * - *(int *)commit->object.sha1 set to the virtual id.
  29  */
  30
  31 static unsigned commit_list_count(const struct commit_list *l)
  32 {
  33         unsigned c = 0;
  34         for (; l; l = l->next )
  35                 c++;
  36         return c;
  37 }
  38
  39 static struct commit *make_virtual_commit(struct tree *tree, const char *comment)
  40 {
  41         struct commit *commit = xcalloc(1, sizeof(struct commit));
  42         static unsigned virtual_id = 1;
  43         commit->tree = tree;
  44         commit->util = (void*)comment;
  45         *(int*)commit->object.sha1 = virtual_id++;
  46         /* avoid warnings */
  47         commit->object.parsed = 1;
  48         return commit;
  49 }
  50
  51 /*
  52  * Since we use get_tree_entry(), which does not put the read object into
  53  * the object pool, we cannot rely on a == b.
  54  */
  55 static int sha_eq(const unsigned char *a, const unsigned char *b)
  56 {
  57         if (!a && !b)
  58                 return 2;
  59         return a && b && hashcmp(a, b) == 0;
  60 }
  61
  62 /*
  63  * Since we want to write the index eventually, we cannot reuse the index
  64  * for these (temporary) data.
  65  */
  66 struct stage_data
  67 {
  68         struct
  69         {
  70                 unsigned mode;
  71                 unsigned char sha[20];
  72         } stages[4];
  73         unsigned processed:1;
  74 };
  75
  76 static struct path_list current_file_set = {NULL, 0, 0, 1};
  77 static struct path_list current_directory_set = {NULL, 0, 0, 1};
  78
  79 static int output_indent = 0;
  80
  81 static void output(const char *fmt, ...)
  82 {
  83         va_list args;
  84         int i;
  85         for (i = output_indent; i--;)
  86                 fputs("  ", stdout);
  87         va_start(args, fmt);
  88         vfprintf(stdout, fmt, args);
  89         va_end(args);
  90         fputc('\n', stdout);
  91 }
  92
  93 static void output_commit_title(struct commit *commit)
  94 {
  95         int i;
  96         for (i = output_indent; i--;)
  97                 fputs("  ", stdout);
  98         if (commit->util)
  99                 printf("virtual %s\n", (char *)commit->util);
 100         else {
 101                 printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
 102                 if (parse_commit(commit) != 0)
 103                         printf("(bad commit)\n");
 104                 else {
 105                         const char *s;
 106                         int len;
 107                         for (s = commit->buffer; *s; s++)
 108                                 if (*s == '\n' && s[1] == '\n') {
 109                                         s += 2;
 110                                         break;
 111                                 }
 112                         for (len = 0; s[len] && '\n' != s[len]; len++)
 113                                 ; /* do nothing */
 114                         printf("%.*s\n", len, s);
 115                 }
 116         }
 117 }
 118
 119 static const char *current_index_file = NULL;
 120 static const char *original_index_file;
 121 static const char *temporary_index_file;
 122 static int cache_dirty = 0;
 123
 124 static int flush_cache(void)
 125 {
 126         /* flush temporary index */
 127         struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
 128         int fd = hold_lock_file_for_update(lock, current_index_file, 1);
 129         if (write_cache(fd, active_cache, active_nr) ||
 130                         close(fd) || commit_lock_file(lock))
 131                 die ("unable to write %s", current_index_file);
 132         discard_cache();
 133         cache_dirty = 0;
 134         return 0;
 135 }
 136
 137 static void setup_index(int temp)
 138 {
 139         current_index_file = temp ? temporary_index_file: original_index_file;
 140         if (cache_dirty) {
 141                 discard_cache();
 142                 cache_dirty = 0;
 143         }
 144         unlink(temporary_index_file);
 145         discard_cache();
 146 }
 147
 148 static struct cache_entry *make_cache_entry(unsigned int mode,
 149                 const unsigned char *sha1, const char *path, int stage, int refresh)
 150 {
 151         int size, len;
 152         struct cache_entry *ce;
 153
 154         if (!verify_path(path))
 155                 return NULL;
 156
 157         len = strlen(path);
 158         size = cache_entry_size(len);
 159         ce = xcalloc(1, size);
 160
 161         hashcpy(ce->sha1, sha1);
 162         memcpy(ce->name, path, len);
 163         ce->ce_flags = create_ce_flags(len, stage);
 164         ce->ce_mode = create_ce_mode(mode);
 165
 166         if (refresh)
 167                 return refresh_cache_entry(ce, 0);
 168
 169         return ce;
 170 }
 171
 172 static 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         if (!cache_dirty)
 177                 read_cache_from(current_index_file);
 178         cache_dirty++;
 179         ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
 180         if (!ce)
 181                 return error("cache_addinfo failed: %s", strerror(cache_errno));
 182         return add_cache_entry(ce, options);
 183 }
 184
 185 /*
 186  * This is a global variable which is used in a number of places but
 187  * only written to in the 'merge' function.
 188  *
 189  * index_only == 1    => Don't leave any non-stage 0 entries in the cache and
 190  *                       don't update the working directory.
 191  *               0    => Leave unmerged entries in the cache and update
 192  *                       the working directory.
 193  */
 194 static int index_only = 0;
 195
 196 static int git_read_tree(struct tree *tree)
 197 {
 198         int rc;
 199         struct object_list *trees = NULL;
 200         struct unpack_trees_options opts;
 201
 202         if (cache_dirty)
 203                 die("read-tree with dirty cache");
 204
 205         memset(&opts, 0, sizeof(opts));
 206         object_list_append(&tree->object, &trees);
 207         rc = unpack_trees(trees, &opts);
 208         cache_tree_free(&active_cache_tree);
 209
 210         if (rc == 0)
 211                 cache_dirty = 1;
 212
 213         return rc;
 214 }
 215
 216 static int git_merge_trees(int index_only,
 217                            struct tree *common,
 218                            struct tree *head,
 219                            struct tree *merge)
 220 {
 221         int rc;
 222         struct object_list *trees = NULL;
 223         struct unpack_trees_options opts;
 224
 225         if (!cache_dirty) {
 226                 read_cache_from(current_index_file);
 227                 cache_dirty = 1;
 228         }
 229
 230         memset(&opts, 0, sizeof(opts));
 231         if (index_only)
 232                 opts.index_only = 1;
 233         else
 234                 opts.update = 1;
 235         opts.merge = 1;
 236         opts.head_idx = 2;
 237         opts.fn = threeway_merge;
 238
 239         object_list_append(&common->object, &trees);
 240         object_list_append(&head->object, &trees);
 241         object_list_append(&merge->object, &trees);
 242
 243         rc = unpack_trees(trees, &opts);
 244         cache_tree_free(&active_cache_tree);
 245
 246         cache_dirty = 1;
 247
 248         return rc;
 249 }
 250
 251 static struct tree *git_write_tree(void)
 252 {
 253         struct tree *result = NULL;
 254
 255         if (cache_dirty) {
 256                 unsigned i;
 257                 for (i = 0; i < active_nr; i++) {
 258                         struct cache_entry *ce = active_cache[i];
 259                         if (ce_stage(ce))
 260                                 return NULL;
 261                 }
 262         } else
 263                 read_cache_from(current_index_file);
 264
 265         if (!active_cache_tree)
 266                 active_cache_tree = cache_tree();
 267
 268         if (!cache_tree_fully_valid(active_cache_tree) &&
 269                         cache_tree_update(active_cache_tree,
 270                                 active_cache, active_nr, 0, 0) < 0)
 271                 die("error building trees");
 272
 273         result = lookup_tree(active_cache_tree->sha1);
 274
 275         flush_cache();
 276         cache_dirty = 0;
 277
 278         return result;
 279 }
 280
 281 static int save_files_dirs(const unsigned char *sha1,
 282                 const char *base, int baselen, const char *path,
 283                 unsigned int mode, int stage)
 284 {
 285         int len = strlen(path);
 286         char *newpath = xmalloc(baselen + len + 1);
 287         memcpy(newpath, base, baselen);
 288         memcpy(newpath + baselen, path, len);
 289         newpath[baselen + len] = '\0';
 290
 291         if (S_ISDIR(mode))
 292                 path_list_insert(newpath, &current_directory_set);
 293         else
 294                 path_list_insert(newpath, &current_file_set);
 295         free(newpath);
 296
 297         return READ_TREE_RECURSIVE;
 298 }
 299
 300 static int get_files_dirs(struct tree *tree)
 301 {
 302         int n;
 303         if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs) != 0)
 304                 return 0;
 305         n = current_file_set.nr + current_directory_set.nr;
 306         return n;
 307 }
 308
 309 /*
 310  * Returns a index_entry instance which doesn't have to correspond to
 311  * a real cache entry in Git's index.
 312  */
 313 static struct stage_data *insert_stage_data(const char *path,
 314                 struct tree *o, struct tree *a, struct tree *b,
 315                 struct path_list *entries)
 316 {
 317         struct path_list_item *item;
 318         struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
 319         get_tree_entry(o->object.sha1, path,
 320                         e->stages[1].sha, &e->stages[1].mode);
 321         get_tree_entry(a->object.sha1, path,
 322                         e->stages[2].sha, &e->stages[2].mode);
 323         get_tree_entry(b->object.sha1, path,
 324                         e->stages[3].sha, &e->stages[3].mode);
 325         item = path_list_insert(path, entries);
 326         item->util = e;
 327         return e;
 328 }
 329
 330 /*
 331  * Create a dictionary mapping file names to stage_data objects. The
 332  * dictionary contains one entry for every path with a non-zero stage entry.
 333  */
 334 static struct path_list *get_unmerged(void)
 335 {
 336         struct path_list *unmerged = xcalloc(1, sizeof(struct path_list));
 337         int i;
 338
 339         unmerged->strdup_paths = 1;
 340         if (!cache_dirty) {
 341                 read_cache_from(current_index_file);
 342                 cache_dirty++;
 343         }
 344         for (i = 0; i < active_nr; i++) {
 345                 struct path_list_item *item;
 346                 struct stage_data *e;
 347                 struct cache_entry *ce = active_cache[i];
 348                 if (!ce_stage(ce))
 349                         continue;
 350
 351                 item = path_list_lookup(ce->name, unmerged);
 352                 if (!item) {
 353                         item = path_list_insert(ce->name, unmerged);
 354                         item->util = xcalloc(1, sizeof(struct stage_data));
 355                 }
 356                 e = item->util;
 357                 e->stages[ce_stage(ce)].mode = ntohl(ce->ce_mode);
 358                 hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
 359         }
 360
 361         return unmerged;
 362 }
 363
 364 struct rename
 365 {
 366         struct diff_filepair *pair;
 367         struct stage_data *src_entry;
 368         struct stage_data *dst_entry;
 369         unsigned processed:1;
 370 };
 371
 372 /*
 373  * Get information of all renames which occured between 'o_tree' and
 374  * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
 375  * 'b_tree') to be able to associate the correct cache entries with
 376  * the rename information. 'tree' is always equal to either a_tree or b_tree.
 377  */
 378 static struct path_list *get_renames(struct tree *tree,
 379                                         struct tree *o_tree,
 380                                         struct tree *a_tree,
 381                                         struct tree *b_tree,
 382                                         struct path_list *entries)
 383 {
 384         int i;
 385         struct path_list *renames;
 386         struct diff_options opts;
 387
 388         renames = xcalloc(1, sizeof(struct path_list));
 389         diff_setup(&opts);
 390         opts.recursive = 1;
 391         opts.detect_rename = DIFF_DETECT_RENAME;
 392         opts.output_format = DIFF_FORMAT_NO_OUTPUT;
 393         if (diff_setup_done(&opts) < 0)
 394                 die("diff setup failed");
 395         diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
 396         diffcore_std(&opts);
 397         for (i = 0; i < diff_queued_diff.nr; ++i) {
 398                 struct path_list_item *item;
 399                 struct rename *re;
 400                 struct diff_filepair *pair = diff_queued_diff.queue[i];
 401                 if (pair->status != 'R') {
 402                         diff_free_filepair(pair);
 403                         continue;
 404                 }
 405                 re = xmalloc(sizeof(*re));
 406                 re->processed = 0;
 407                 re->pair = pair;
 408                 item = path_list_lookup(re->pair->one->path, entries);
 409                 if (!item)
 410                         re->src_entry = insert_stage_data(re->pair->one->path,
 411                                         o_tree, a_tree, b_tree, entries);
 412                 else
 413                         re->src_entry = item->util;
 414
 415                 item = path_list_lookup(re->pair->two->path, entries);
 416                 if (!item)
 417                         re->dst_entry = insert_stage_data(re->pair->two->path,
 418                                         o_tree, a_tree, b_tree, entries);
 419                 else
 420                         re->dst_entry = item->util;
 421                 item = path_list_insert(pair->one->path, renames);
 422                 item->util = re;
 423         }
 424         opts.output_format = DIFF_FORMAT_NO_OUTPUT;
 425         diff_queued_diff.nr = 0;
 426         diff_flush(&opts);
 427         return renames;
 428 }
 429
 430 static int update_stages(const char *path, struct diff_filespec *o,
 431                          struct diff_filespec *a, struct diff_filespec *b,
 432                          int clear)
 433 {
 434         int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
 435         if (clear)
 436                 if (remove_file_from_cache(path))
 437                         return -1;
 438         if (o)
 439                 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
 440                         return -1;
 441         if (a)
 442                 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
 443                         return -1;
 444         if (b)
 445                 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
 446                         return -1;
 447         return 0;
 448 }
 449
 450 static int remove_path(const char *name)
 451 {
 452         int ret, len;
 453         char *slash, *dirs;
 454
 455         ret = unlink(name);
 456         if (ret)
 457                 return ret;
 458         len = strlen(name);
 459         dirs = xmalloc(len+1);
 460         memcpy(dirs, name, len);
 461         dirs[len] = '\0';
 462         while ((slash = strrchr(name, '/'))) {
 463                 *slash = '\0';
 464                 len = slash - name;
 465                 if (rmdir(name) != 0)
 466                         break;
 467         }
 468         free(dirs);
 469         return ret;
 470 }
 471
 472 static int remove_file(int clean, const char *path, int no_wd)
 473 {
 474         int update_cache = index_only || clean;
 475         int update_working_directory = !index_only && !no_wd;
 476
 477         if (update_cache) {
 478                 if (!cache_dirty)
 479                         read_cache_from(current_index_file);
 480                 cache_dirty++;
 481                 if (remove_file_from_cache(path))
 482                         return -1;
 483         }
 484         if (update_working_directory) {
 485                 unlink(path);
 486                 if (errno != ENOENT || errno != EISDIR)
 487                         return -1;
 488                 remove_path(path);
 489         }
 490         return 0;
 491 }
 492
 493 static char *unique_path(const char *path, const char *branch)
 494 {
 495         char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
 496         int suffix = 0;
 497         struct stat st;
 498         char *p = newpath + strlen(path);
 499         strcpy(newpath, path);
 500         *(p++) = '~';
 501         strcpy(p, branch);
 502         for (; *p; ++p)
 503                 if ('/' == *p)
 504                         *p = '_';
 505         while (path_list_has_path(&current_file_set, newpath) ||
 506                path_list_has_path(&current_directory_set, newpath) ||
 507                lstat(newpath, &st) == 0)
 508                 sprintf(p, "_%d", suffix++);
 509
 510         path_list_insert(newpath, &current_file_set);
 511         return newpath;
 512 }
 513
 514 static int mkdir_p(const char *path, unsigned long mode)
 515 {
 516         /* path points to cache entries, so xstrdup before messing with it */
 517         char *buf = xstrdup(path);
 518         int result = safe_create_leading_directories(buf);
 519         free(buf);
 520         return result;
 521 }
 522
 523 static void flush_buffer(int fd, const char *buf, unsigned long size)
 524 {
 525         while (size > 0) {
 526                 long ret = xwrite(fd, buf, size);
 527                 if (ret < 0) {
 528                         /* Ignore epipe */
 529                         if (errno == EPIPE)
 530                                 break;
 531                         die("merge-recursive: %s", strerror(errno));
 532                 } else if (!ret) {
 533                         die("merge-recursive: disk full?");
 534                 }
 535                 size -= ret;
 536                 buf += ret;
 537         }
 538 }
 539
 540 static 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
 549         if (update_wd) {
 550                 char type[20];
 551                 void *buf;
 552                 unsigned long size;
 553
 554                 buf = read_sha1_file(sha, type, &size);
 555                 if (!buf)
 556                         die("cannot read object %s '%s'", sha1_to_hex(sha), path);
 557                 if (strcmp(type, blob_type) != 0)
 558                         die("blob expected for %s '%s'", sha1_to_hex(sha), path);
 559
 560                 if (S_ISREG(mode)) {
 561                         int fd;
 562                         if (mkdir_p(path, 0777))
 563                                 die("failed to create path %s: %s", path, strerror(errno));
 564                         unlink(path);
 565                         if (mode & 0100)
 566                                 mode = 0777;
 567                         else
 568                                 mode = 0666;
 569                         fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
 570                         if (fd < 0)
 571                                 die("failed to open %s: %s", path, strerror(errno));
 572                         flush_buffer(fd, buf, size);
 573                         close(fd);
 574                 } else if (S_ISLNK(mode)) {
 575                         char *lnk = xmalloc(size + 1);
 576                         memcpy(lnk, buf, size);
 577                         lnk[size] = '\0';
 578                         mkdir_p(path, 0777);
 579                         unlink(lnk);
 580                         symlink(lnk, path);
 581                 } else
 582                         die("do not know what to do with %06o %s '%s'",
 583                             mode, sha1_to_hex(sha), path);
 584         }
 585         if (update_cache)
 586                 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
 587 }
 588
 589 static void update_file(int clean,
 590                         const unsigned char *sha,
 591                         unsigned mode,
 592                         const char *path)
 593 {
 594         update_file_flags(sha, mode, path, index_only || clean, !index_only);
 595 }
 596
 597 /* Low level file merging, update and removal */
 598
 599 struct merge_file_info
 600 {
 601         unsigned char sha[20];
 602         unsigned mode;
 603         unsigned clean:1,
 604                  merge:1;
 605 };
 606
 607 static char *git_unpack_file(const unsigned char *sha1, char *path)
 608 {
 609         void *buf;
 610         char type[20];
 611         unsigned long size;
 612         int fd;
 613
 614         buf = read_sha1_file(sha1, type, &size);
 615         if (!buf || strcmp(type, blob_type))
 616                 die("unable to read blob object %s", sha1_to_hex(sha1));
 617
 618         strcpy(path, ".merge_file_XXXXXX");
 619         fd = mkstemp(path);
 620         if (fd < 0)
 621                 die("unable to create temp-file");
 622         flush_buffer(fd, buf, size);
 623         close(fd);
 624         return path;
 625 }
 626
 627 static struct merge_file_info merge_file(struct diff_filespec *o,
 628                 struct diff_filespec *a, struct diff_filespec *b,
 629                 const char *branch1, const char *branch2)
 630 {
 631         struct merge_file_info result;
 632         result.merge = 0;
 633         result.clean = 1;
 634
 635         if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
 636                 result.clean = 0;
 637                 if (S_ISREG(a->mode)) {
 638                         result.mode = a->mode;
 639                         hashcpy(result.sha, a->sha1);
 640                 } else {
 641                         result.mode = b->mode;
 642                         hashcpy(result.sha, b->sha1);
 643                 }
 644         } else {
 645                 if (!sha_eq(a->sha1, o->sha1) && !sha_eq(b->sha1, o->sha1))
 646                         result.merge = 1;
 647
 648                 result.mode = a->mode == o->mode ? b->mode: a->mode;
 649
 650                 if (sha_eq(a->sha1, o->sha1))
 651                         hashcpy(result.sha, b->sha1);
 652                 else if (sha_eq(b->sha1, o->sha1))
 653                         hashcpy(result.sha, a->sha1);
 654                 else if (S_ISREG(a->mode)) {
 655                         int code = 1, fd;
 656                         struct stat st;
 657                         char orig[PATH_MAX];
 658                         char src1[PATH_MAX];
 659                         char src2[PATH_MAX];
 660                         const char *argv[] = {
 661                                 "merge", "-L", NULL, "-L", NULL, "-L", NULL,
 662                                 NULL, NULL, NULL,
 663                                 NULL
 664                         };
 665                         char *la, *lb, *lo;
 666
 667                         git_unpack_file(o->sha1, orig);
 668                         git_unpack_file(a->sha1, src1);
 669                         git_unpack_file(b->sha1, src2);
 670
 671                         argv[2] = la = xstrdup(mkpath("%s/%s", branch1, a->path));
 672                         argv[6] = lb = xstrdup(mkpath("%s/%s", branch2, b->path));
 673                         argv[4] = lo = xstrdup(mkpath("orig/%s", o->path));
 674                         argv[7] = src1;
 675                         argv[8] = orig;
 676                         argv[9] = src2,
 677
 678                         code = run_command_v(10, argv);
 679
 680                         free(la);
 681                         free(lb);
 682                         free(lo);
 683                         if (code && code < -256) {
 684                                 die("Failed to execute 'merge'. merge(1) is used as the "
 685                                     "file-level merge tool. Is 'merge' in your path?");
 686                         }
 687                         fd = open(src1, O_RDONLY);
 688                         if (fd < 0 || fstat(fd, &st) < 0 ||
 689                                         index_fd(result.sha, fd, &st, 1,
 690                                                 "blob"))
 691                                 die("Unable to add %s to database", src1);
 692
 693                         unlink(orig);
 694                         unlink(src1);
 695                         unlink(src2);
 696
 697                         result.clean = WEXITSTATUS(code) == 0;
 698                 } else {
 699                         if (!(S_ISLNK(a->mode) || S_ISLNK(b->mode)))
 700                                 die("cannot merge modes?");
 701
 702                         hashcpy(result.sha, a->sha1);
 703
 704                         if (!sha_eq(a->sha1, b->sha1))
 705                                 result.clean = 0;
 706                 }
 707         }
 708
 709         return result;
 710 }
 711
 712 static void conflict_rename_rename(struct rename *ren1,
 713                                    const char *branch1,
 714                                    struct rename *ren2,
 715                                    const char *branch2)
 716 {
 717         char *del[2];
 718         int delp = 0;
 719         const char *ren1_dst = ren1->pair->two->path;
 720         const char *ren2_dst = ren2->pair->two->path;
 721         const char *dst_name1 = ren1_dst;
 722         const char *dst_name2 = ren2_dst;
 723         if (path_list_has_path(&current_directory_set, ren1_dst)) {
 724                 dst_name1 = del[delp++] = unique_path(ren1_dst, branch1);
 725                 output("%s is a directory in %s adding as %s instead",
 726                        ren1_dst, branch2, dst_name1);
 727                 remove_file(0, ren1_dst, 0);
 728         }
 729         if (path_list_has_path(&current_directory_set, ren2_dst)) {
 730                 dst_name2 = del[delp++] = unique_path(ren2_dst, branch2);
 731                 output("%s is a directory in %s adding as %s instead",
 732                        ren2_dst, branch1, dst_name2);
 733                 remove_file(0, ren2_dst, 0);
 734         }
 735         update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
 736         update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
 737         while (delp--)
 738                 free(del[delp]);
 739 }
 740
 741 static void conflict_rename_dir(struct rename *ren1,
 742                                 const char *branch1)
 743 {
 744         char *new_path = unique_path(ren1->pair->two->path, branch1);
 745         output("Renaming %s to %s instead", ren1->pair->one->path, new_path);
 746         remove_file(0, ren1->pair->two->path, 0);
 747         update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
 748         free(new_path);
 749 }
 750
 751 static void conflict_rename_rename_2(struct rename *ren1,
 752                                      const char *branch1,
 753                                      struct rename *ren2,
 754                                      const char *branch2)
 755 {
 756         char *new_path1 = unique_path(ren1->pair->two->path, branch1);
 757         char *new_path2 = unique_path(ren2->pair->two->path, branch2);
 758         output("Renaming %s to %s and %s to %s instead",
 759                ren1->pair->one->path, new_path1,
 760                ren2->pair->one->path, new_path2);
 761         remove_file(0, ren1->pair->two->path, 0);
 762         update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
 763         update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
 764         free(new_path2);
 765         free(new_path1);
 766 }
 767
 768 static int process_renames(struct path_list *a_renames,
 769                            struct path_list *b_renames,
 770                            const char *a_branch,
 771                            const char *b_branch)
 772 {
 773         int clean_merge = 1, i, j;
 774         struct path_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
 775         const struct rename *sre;
 776
 777         for (i = 0; i < a_renames->nr; i++) {
 778                 sre = a_renames->items[i].util;
 779                 path_list_insert(sre->pair->two->path, &a_by_dst)->util
 780                         = sre->dst_entry;
 781         }
 782         for (i = 0; i < b_renames->nr; i++) {
 783                 sre = b_renames->items[i].util;
 784                 path_list_insert(sre->pair->two->path, &b_by_dst)->util
 785                         = sre->dst_entry;
 786         }
 787
 788         for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
 789                 int compare;
 790                 char *src;
 791                 struct path_list *renames1, *renames2, *renames2Dst;
 792                 struct rename *ren1 = NULL, *ren2 = NULL;
 793                 const char *branch1, *branch2;
 794                 const char *ren1_src, *ren1_dst;
 795
 796                 if (i >= a_renames->nr) {
 797                         compare = 1;
 798                         ren2 = b_renames->items[j++].util;
 799                 } else if (j >= b_renames->nr) {
 800                         compare = -1;
 801                         ren1 = a_renames->items[i++].util;
 802                 } else {
 803                         compare = strcmp(a_renames->items[i].path,
 804                                         b_renames->items[j].path);
 805                         if (compare <= 0)
 806                                 ren1 = a_renames->items[i++].util;
 807                         if (compare >= 0)
 808                                 ren2 = b_renames->items[j++].util;
 809                 }
 810
 811                 /* TODO: refactor, so that 1/2 are not needed */
 812                 if (ren1) {
 813                         renames1 = a_renames;
 814                         renames2 = b_renames;
 815                         renames2Dst = &b_by_dst;
 816                         branch1 = a_branch;
 817                         branch2 = b_branch;
 818                 } else {
 819                         struct rename *tmp;
 820                         renames1 = b_renames;
 821                         renames2 = a_renames;
 822                         renames2Dst = &a_by_dst;
 823                         branch1 = b_branch;
 824                         branch2 = a_branch;
 825                         tmp = ren2;
 826                         ren2 = ren1;
 827                         ren1 = tmp;
 828                 }
 829                 src = ren1->pair->one->path;
 830
 831                 ren1->dst_entry->processed = 1;
 832                 ren1->src_entry->processed = 1;
 833
 834                 if (ren1->processed)
 835                         continue;
 836                 ren1->processed = 1;
 837
 838                 ren1_src = ren1->pair->one->path;
 839                 ren1_dst = ren1->pair->two->path;
 840
 841                 if (ren2) {
 842                         const char *ren2_src = ren2->pair->one->path;
 843                         const char *ren2_dst = ren2->pair->two->path;
 844                         /* Renamed in 1 and renamed in 2 */
 845                         if (strcmp(ren1_src, ren2_src) != 0)
 846                                 die("ren1.src != ren2.src");
 847                         ren2->dst_entry->processed = 1;
 848                         ren2->processed = 1;
 849                         if (strcmp(ren1_dst, ren2_dst) != 0) {
 850                                 clean_merge = 0;
 851                                 output("CONFLICT (rename/rename): "
 852                                        "Rename %s->%s in branch %s "
 853                                        "rename %s->%s in %s",
 854                                        src, ren1_dst, branch1,
 855                                        src, ren2_dst, branch2);
 856                                 conflict_rename_rename(ren1, branch1, ren2, branch2);
 857                         } else {
 858                                 struct merge_file_info mfi;
 859                                 remove_file(1, ren1_src, 1);
 860                                 mfi = merge_file(ren1->pair->one,
 861                                                  ren1->pair->two,
 862                                                  ren2->pair->two,
 863                                                  branch1,
 864                                                  branch2);
 865                                 if (mfi.merge || !mfi.clean)
 866                                         output("Renaming %s->%s", src, ren1_dst);
 867
 868                                 if (mfi.merge)
 869                                         output("Auto-merging %s", ren1_dst);
 870
 871                                 if (!mfi.clean) {
 872                                         output("CONFLICT (content): merge conflict in %s",
 873                                                ren1_dst);
 874                                         clean_merge = 0;
 875
 876                                         if (!index_only)
 877                                                 update_stages(ren1_dst,
 878                                                               ren1->pair->one,
 879                                                               ren1->pair->two,
 880                                                               ren2->pair->two,
 881                                                               1 /* clear */);
 882                                 }
 883                                 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
 884                         }
 885                 } else {
 886                         /* Renamed in 1, maybe changed in 2 */
 887                         struct path_list_item *item;
 888                         /* we only use sha1 and mode of these */
 889                         struct diff_filespec src_other, dst_other;
 890                         int try_merge, stage = a_renames == renames1 ? 3: 2;
 891
 892                         remove_file(1, ren1_src, 1);
 893
 894                         hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
 895                         src_other.mode = ren1->src_entry->stages[stage].mode;
 896                         hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha);
 897                         dst_other.mode = ren1->dst_entry->stages[stage].mode;
 898
 899                         try_merge = 0;
 900
 901                         if (path_list_has_path(&current_directory_set, ren1_dst)) {
 902                                 clean_merge = 0;
 903                                 output("CONFLICT (rename/directory): Rename %s->%s in %s "
 904                                        " directory %s added in %s",
 905                                        ren1_src, ren1_dst, branch1,
 906                                        ren1_dst, branch2);
 907                                 conflict_rename_dir(ren1, branch1);
 908                         } else if (sha_eq(src_other.sha1, null_sha1)) {
 909                                 clean_merge = 0;
 910                                 output("CONFLICT (rename/delete): Rename %s->%s in %s "
 911                                        "and deleted in %s",
 912                                        ren1_src, ren1_dst, branch1,
 913                                        branch2);
 914                                 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
 915                         } else if (!sha_eq(dst_other.sha1, null_sha1)) {
 916                                 const char *new_path;
 917                                 clean_merge = 0;
 918                                 try_merge = 1;
 919                                 output("CONFLICT (rename/add): Rename %s->%s in %s. "
 920                                        "%s added in %s",
 921                                        ren1_src, ren1_dst, branch1,
 922                                        ren1_dst, branch2);
 923                                 new_path = unique_path(ren1_dst, branch2);
 924                                 output("Adding as %s instead", new_path);
 925                                 update_file(0, dst_other.sha1, dst_other.mode, new_path);
 926                         } else if ((item = path_list_lookup(ren1_dst, renames2Dst))) {
 927                                 ren2 = item->util;
 928                                 clean_merge = 0;
 929                                 ren2->processed = 1;
 930                                 output("CONFLICT (rename/rename): Rename %s->%s in %s. "
 931                                        "Rename %s->%s in %s",
 932                                        ren1_src, ren1_dst, branch1,
 933                                        ren2->pair->one->path, ren2->pair->two->path, branch2);
 934                                 conflict_rename_rename_2(ren1, branch1, ren2, branch2);
 935                         } else
 936                                 try_merge = 1;
 937
 938                         if (try_merge) {
 939                                 struct diff_filespec *o, *a, *b;
 940                                 struct merge_file_info mfi;
 941                                 src_other.path = (char *)ren1_src;
 942
 943                                 o = ren1->pair->one;
 944                                 if (a_renames == renames1) {
 945                                         a = ren1->pair->two;
 946                                         b = &src_other;
 947                                 } else {
 948                                         b = ren1->pair->two;
 949                                         a = &src_other;
 950                                 }
 951                                 mfi = merge_file(o, a, b,
 952                                                 a_branch, b_branch);
 953
 954                                 if (mfi.merge || !mfi.clean)
 955                                         output("Renaming %s => %s", ren1_src, ren1_dst);
 956                                 if (mfi.merge)
 957                                         output("Auto-merging %s", ren1_dst);
 958                                 if (!mfi.clean) {
 959                                         output("CONFLICT (rename/modify): Merge conflict in %s",
 960                                                ren1_dst);
 961                                         clean_merge = 0;
 962
 963                                         if (!index_only)
 964                                                 update_stages(ren1_dst,
 965                                                                 o, a, b, 1);
 966                                 }
 967                                 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
 968                         }
 969                 }
 970         }
 971         path_list_clear(&a_by_dst, 0);
 972         path_list_clear(&b_by_dst, 0);
 973
 974         if (cache_dirty)
 975                 flush_cache();
 976         return clean_merge;
 977 }
 978
 979 static unsigned char *has_sha(const unsigned char *sha)
 980 {
 981         return is_null_sha1(sha) ? NULL: (unsigned char *)sha;
 982 }
 983
 984 /* Per entry merge function */
 985 static int process_entry(const char *path, struct stage_data *entry,
 986                          const char *branch1,
 987                          const char *branch2)
 988 {
 989         /*
 990         printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
 991         print_index_entry("\tpath: ", entry);
 992         */
 993         int clean_merge = 1;
 994         unsigned char *o_sha = has_sha(entry->stages[1].sha);
 995         unsigned char *a_sha = has_sha(entry->stages[2].sha);
 996         unsigned char *b_sha = has_sha(entry->stages[3].sha);
 997         unsigned o_mode = entry->stages[1].mode;
 998         unsigned a_mode = entry->stages[2].mode;
 999         unsigned b_mode = entry->stages[3].mode;
1000
1001         if (o_sha && (!a_sha || !b_sha)) {
1002                 /* Case A: Deleted in one */
1003                 if ((!a_sha && !b_sha) ||
1004                     (sha_eq(a_sha, o_sha) && !b_sha) ||
1005                     (!a_sha && sha_eq(b_sha, o_sha))) {
1006                         /* Deleted in both or deleted in one and
1007                          * unchanged in the other */
1008                         if (a_sha)
1009                                 output("Removing %s", path);
1010                         /* do not touch working file if it did not exist */
1011                         remove_file(1, path, !a_sha);
1012                 } else {
1013                         /* Deleted in one and changed in the other */
1014                         clean_merge = 0;
1015                         if (!a_sha) {
1016                                 output("CONFLICT (delete/modify): %s deleted in %s "
1017                                        "and modified in %s. Version %s of %s left in tree.",
1018                                        path, branch1,
1019                                        branch2, branch2, path);
1020                                 update_file(0, b_sha, b_mode, path);
1021                         } else {
1022                                 output("CONFLICT (delete/modify): %s deleted in %s "
1023                                        "and modified in %s. Version %s of %s left in tree.",
1024                                        path, branch2,
1025                                        branch1, branch1, path);
1026                                 update_file(0, a_sha, a_mode, path);
1027                         }
1028                 }
1029
1030         } else if ((!o_sha && a_sha && !b_sha) ||
1031                    (!o_sha && !a_sha && b_sha)) {
1032                 /* Case B: Added in one. */
1033                 const char *add_branch;
1034                 const char *other_branch;
1035                 unsigned mode;
1036                 const unsigned char *sha;
1037                 const char *conf;
1038
1039                 if (a_sha) {
1040                         add_branch = branch1;
1041                         other_branch = branch2;
1042                         mode = a_mode;
1043                         sha = a_sha;
1044                         conf = "file/directory";
1045                 } else {
1046                         add_branch = branch2;
1047                         other_branch = branch1;
1048                         mode = b_mode;
1049                         sha = b_sha;
1050                         conf = "directory/file";
1051                 }
1052                 if (path_list_has_path(&current_directory_set, path)) {
1053                         const char *new_path = unique_path(path, add_branch);
1054                         clean_merge = 0;
1055                         output("CONFLICT (%s): There is a directory with name %s in %s. "
1056                                "Adding %s as %s",
1057                                conf, path, other_branch, path, new_path);
1058                         remove_file(0, path, 0);
1059                         update_file(0, sha, mode, new_path);
1060                 } else {
1061                         output("Adding %s", path);
1062                         update_file(1, sha, mode, path);
1063                 }
1064         } else if (!o_sha && a_sha && b_sha) {
1065                 /* Case C: Added in both (check for same permissions). */
1066                 if (sha_eq(a_sha, b_sha)) {
1067                         if (a_mode != b_mode) {
1068                                 clean_merge = 0;
1069                                 output("CONFLICT: File %s added identically in both branches, "
1070                                        "but permissions conflict %06o->%06o",
1071                                        path, a_mode, b_mode);
1072                                 output("CONFLICT: adding with permission: %06o", a_mode);
1073                                 update_file(0, a_sha, a_mode, path);
1074                         } else {
1075                                 /* This case is handled by git-read-tree */
1076                                 assert(0 && "This case must be handled by git-read-tree");
1077                         }
1078                 } else {
1079                         const char *new_path1, *new_path2;
1080                         clean_merge = 0;
1081                         new_path1 = unique_path(path, branch1);
1082                         new_path2 = unique_path(path, branch2);
1083                         output("CONFLICT (add/add): File %s added non-identically "
1084                                "in both branches. Adding as %s and %s instead.",
1085                                path, new_path1, new_path2);
1086                         remove_file(0, path, 0);
1087                         update_file(0, a_sha, a_mode, new_path1);
1088                         update_file(0, b_sha, b_mode, new_path2);
1089                 }
1090
1091         } else if (o_sha && a_sha && b_sha) {
1092                 /* case D: Modified in both, but differently. */
1093                 struct merge_file_info mfi;
1094                 struct diff_filespec o, a, b;
1095
1096                 output("Auto-merging %s", path);
1097                 o.path = a.path = b.path = (char *)path;
1098                 hashcpy(o.sha1, o_sha);
1099                 o.mode = o_mode;
1100                 hashcpy(a.sha1, a_sha);
1101                 a.mode = a_mode;
1102                 hashcpy(b.sha1, b_sha);
1103                 b.mode = b_mode;
1104
1105                 mfi = merge_file(&o, &a, &b,
1106                                  branch1, branch2);
1107
1108                 if (mfi.clean)
1109                         update_file(1, mfi.sha, mfi.mode, path);
1110                 else {
1111                         clean_merge = 0;
1112                         output("CONFLICT (content): Merge conflict in %s", path);
1113
1114                         if (index_only)
1115                                 update_file(0, mfi.sha, mfi.mode, path);
1116                         else
1117                                 update_file_flags(mfi.sha, mfi.mode, path,
1118                                               0 /* update_cache */, 1 /* update_working_directory */);
1119                 }
1120         } else
1121                 die("Fatal merge failure, shouldn't happen.");
1122
1123         if (cache_dirty)
1124                 flush_cache();
1125
1126         return clean_merge;
1127 }
1128
1129 static int merge_trees(struct tree *head,
1130                        struct tree *merge,
1131                        struct tree *common,
1132                        const char *branch1,
1133                        const char *branch2,
1134                        struct tree **result)
1135 {
1136         int code, clean;
1137         if (sha_eq(common->object.sha1, merge->object.sha1)) {
1138                 output("Already uptodate!");
1139                 *result = head;
1140                 return 1;
1141         }
1142
1143         code = git_merge_trees(index_only, common, head, merge);
1144
1145         if (code != 0)
1146                 die("merging of trees %s and %s failed",
1147                     sha1_to_hex(head->object.sha1),
1148                     sha1_to_hex(merge->object.sha1));
1149
1150         *result = git_write_tree();
1151
1152         if (!*result) {
1153                 struct path_list *entries, *re_head, *re_merge;
1154                 int i;
1155                 path_list_clear(&current_file_set, 1);
1156                 path_list_clear(&current_directory_set, 1);
1157                 get_files_dirs(head);
1158                 get_files_dirs(merge);
1159
1160                 entries = get_unmerged();
1161                 re_head  = get_renames(head, common, head, merge, entries);
1162                 re_merge = get_renames(merge, common, head, merge, entries);
1163                 clean = process_renames(re_head, re_merge,
1164                                 branch1, branch2);
1165                 for (i = 0; i < entries->nr; i++) {
1166                         const char *path = entries->items[i].path;
1167                         struct stage_data *e = entries->items[i].util;
1168                         if (e->processed)
1169                                 continue;
1170                         if (!process_entry(path, e, branch1, branch2))
1171                                 clean = 0;
1172                 }
1173
1174                 path_list_clear(re_merge, 0);
1175                 path_list_clear(re_head, 0);
1176                 path_list_clear(entries, 1);
1177
1178                 if (clean || index_only)
1179                         *result = git_write_tree();
1180                 else
1181                         *result = NULL;
1182         } else {
1183                 clean = 1;
1184                 printf("merging of trees %s and %s resulted in %s\n",
1185                        sha1_to_hex(head->object.sha1),
1186                        sha1_to_hex(merge->object.sha1),
1187                        sha1_to_hex((*result)->object.sha1));
1188         }
1189
1190         return clean;
1191 }
1192
1193 static struct commit_list *reverse_commit_list(struct commit_list *list)
1194 {
1195         struct commit_list *next = NULL, *current, *backup;
1196         for (current = list; current; current = backup) {
1197                 backup = current->next;
1198                 current->next = next;
1199                 next = current;
1200         }
1201         return next;
1202 }
1203
1204 /*
1205  * Merge the commits h1 and h2, return the resulting virtual
1206  * commit object and a flag indicating the cleaness of the merge.
1207  */
1208 static int merge(struct commit *h1,
1209                  struct commit *h2,
1210                  const char *branch1,
1211                  const char *branch2,
1212                  int call_depth /* =0 */,
1213                  struct commit *ancestor /* =None */,
1214                  struct commit **result)
1215 {
1216         struct commit_list *ca = NULL, *iter;
1217         struct commit *merged_common_ancestors;
1218         struct tree *mrtree;
1219         int clean;
1220
1221         output("Merging:");
1222         output_commit_title(h1);
1223         output_commit_title(h2);
1224
1225         if (ancestor)
1226                 commit_list_insert(ancestor, &ca);
1227         else
1228                 ca = reverse_commit_list(get_merge_bases(h1, h2, 1));
1229
1230         output("found %u common ancestor(s):", commit_list_count(ca));
1231         for (iter = ca; iter; iter = iter->next)
1232                 output_commit_title(iter->item);
1233
1234         merged_common_ancestors = pop_commit(&ca);
1235         if (merged_common_ancestors == NULL) {
1236                 /* if there is no common ancestor, make an empty tree */
1237                 struct tree *tree = xcalloc(1, sizeof(struct tree));
1238
1239                 tree->object.parsed = 1;
1240                 tree->object.type = OBJ_TREE;
1241                 write_sha1_file(NULL, 0, tree_type, tree->object.sha1);
1242                 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1243         }
1244
1245         for (iter = ca; iter; iter = iter->next) {
1246                 output_indent = call_depth + 1;
1247                 /*
1248                  * When the merge fails, the result contains files
1249                  * with conflict markers. The cleanness flag is
1250                  * ignored, it was never acutally used, as result of
1251                  * merge_trees has always overwritten it: the commited
1252                  * "conflicts" were already resolved.
1253                  */
1254                 merge(merged_common_ancestors, iter->item,
1255                       "Temporary merge branch 1",
1256                       "Temporary merge branch 2",
1257                       call_depth + 1,
1258                       NULL,
1259                       &merged_common_ancestors);
1260                 output_indent = call_depth;
1261
1262                 if (!merged_common_ancestors)
1263                         die("merge returned no commit");
1264         }
1265
1266         if (call_depth == 0) {
1267                 setup_index(0 /* $GIT_DIR/index */);
1268                 index_only = 0;
1269         } else {
1270                 setup_index(1 /* temporary index */);
1271                 git_read_tree(h1->tree);
1272                 index_only = 1;
1273         }
1274
1275         clean = merge_trees(h1->tree, h2->tree, merged_common_ancestors->tree,
1276                             branch1, branch2, &mrtree);
1277
1278         if (!ancestor && (clean || index_only)) {
1279                 *result = make_virtual_commit(mrtree, "merged tree");
1280                 commit_list_insert(h1, &(*result)->parents);
1281                 commit_list_insert(h2, &(*result)->parents->next);
1282         } else
1283                 *result = NULL;
1284
1285         return clean;
1286 }
1287
1288 static struct commit *get_ref(const char *ref)
1289 {
1290         unsigned char sha1[20];
1291         struct object *object;
1292
1293         if (get_sha1(ref, sha1))
1294                 die("Could not resolve ref '%s'", ref);
1295         object = deref_tag(parse_object(sha1), ref, strlen(ref));
1296         if (object->type != OBJ_COMMIT)
1297                 return NULL;
1298         if (parse_commit((struct commit *)object))
1299                 die("Could not parse commit '%s'", sha1_to_hex(object->sha1));
1300         return (struct commit *)object;
1301 }
1302
1303 int main(int argc, char *argv[])
1304 {
1305         static const char *bases[2];
1306         static unsigned bases_count = 0;
1307         int i, clean;
1308         const char *branch1, *branch2;
1309         struct commit *result, *h1, *h2;
1310
1311         git_config(git_default_config); /* core.filemode */
1312         original_index_file = getenv("GIT_INDEX_FILE");
1313
1314         if (!original_index_file)
1315                 original_index_file = xstrdup(git_path("index"));
1316
1317         temporary_index_file = xstrdup(git_path("mrg-rcrsv-tmp-idx"));
1318
1319         if (argc < 4)
1320                 die("Usage: %s <base>... -- <head> <remote> ...\n", argv[0]);
1321
1322         for (i = 1; i < argc; ++i) {
1323                 if (!strcmp(argv[i], "--"))
1324                         break;
1325                 if (bases_count < sizeof(bases)/sizeof(*bases))
1326                         bases[bases_count++] = argv[i];
1327         }
1328         if (argc - i != 3) /* "--" "<head>" "<remote>" */
1329                 die("Not handling anything other than two heads merge.");
1330
1331         branch1 = argv[++i];
1332         branch2 = argv[++i];
1333         printf("Merging %s with %s\n", branch1, branch2);
1334
1335         h1 = get_ref(branch1);
1336         h2 = get_ref(branch2);
1337
1338         if (bases_count == 1) {
1339                 struct commit *ancestor = get_ref(bases[0]);
1340                 clean = merge(h1, h2, branch1, branch2, 0, ancestor, &result);
1341         } else
1342                 clean = merge(h1, h2, branch1, branch2, 0, NULL, &result);
1343
1344         if (cache_dirty)
1345                 flush_cache();
1346
1347         return clean ? 0: 1;
1348 }
1349
1350 /*
1351 vim: sw=8 noet
1352 */