git.oblomov.eu Git - git/blob - submodule.c

   1 #include "cache.h"
   2 #include "submodule-config.h"
   3 #include "submodule.h"
   4 #include "dir.h"
   5 #include "diff.h"
   6 #include "commit.h"
   7 #include "revision.h"
   8 #include "run-command.h"
   9 #include "diffcore.h"
  10 #include "refs.h"
  11 #include "string-list.h"
  12 #include "sha1-array.h"
  13 #include "argv-array.h"
  14 #include "blob.h"
  15 #include "thread-utils.h"
  16 #include "quote.h"
  17
  18 static int config_fetch_recurse_submodules = RECURSE_SUBMODULES_ON_DEMAND;
  19 static int parallel_jobs = 1;
  20 static struct string_list changed_submodule_paths = STRING_LIST_INIT_NODUP;
  21 static int initialized_fetch_ref_tips;
  22 static struct sha1_array ref_tips_before_fetch;
  23 static struct sha1_array ref_tips_after_fetch;
  24
  25 /*
  26  * The following flag is set if the .gitmodules file is unmerged. We then
  27  * disable recursion for all submodules where .git/config doesn't have a
  28  * matching config entry because we can't guess what might be configured in
  29  * .gitmodules unless the user resolves the conflict. When a command line
  30  * option is given (which always overrides configuration) this flag will be
  31  * ignored.
  32  */
  33 static int gitmodules_is_unmerged;
  34
  35 /*
  36  * This flag is set if the .gitmodules file had unstaged modifications on
  37  * startup. This must be checked before allowing modifications to the
  38  * .gitmodules file with the intention to stage them later, because when
  39  * continuing we would stage the modifications the user didn't stage herself
  40  * too. That might change in a future version when we learn to stage the
  41  * changes we do ourselves without staging any previous modifications.
  42  */
  43 static int gitmodules_is_modified;
  44
  45 int is_staging_gitmodules_ok(void)
  46 {
  47         return !gitmodules_is_modified;
  48 }
  49
  50 /*
  51  * Try to update the "path" entry in the "submodule.<name>" section of the
  52  * .gitmodules file. Return 0 only if a .gitmodules file was found, a section
  53  * with the correct path=<oldpath> setting was found and we could update it.
  54  */
  55 int update_path_in_gitmodules(const char *oldpath, const char *newpath)
  56 {
  57         struct strbuf entry = STRBUF_INIT;
  58         const struct submodule *submodule;
  59
  60         if (!file_exists(".gitmodules")) /* Do nothing without .gitmodules */
  61                 return -1;
  62
  63         if (gitmodules_is_unmerged)
  64                 die(_("Cannot change unmerged .gitmodules, resolve merge conflicts first"));
  65
  66         submodule = submodule_from_path(null_sha1, oldpath);
  67         if (!submodule || !submodule->name) {
  68                 warning(_("Could not find section in .gitmodules where path=%s"), oldpath);
  69                 return -1;
  70         }
  71         strbuf_addstr(&entry, "submodule.");
  72         strbuf_addstr(&entry, submodule->name);
  73         strbuf_addstr(&entry, ".path");
  74         if (git_config_set_in_file_gently(".gitmodules", entry.buf, newpath) < 0) {
  75                 /* Maybe the user already did that, don't error out here */
  76                 warning(_("Could not update .gitmodules entry %s"), entry.buf);
  77                 strbuf_release(&entry);
  78                 return -1;
  79         }
  80         strbuf_release(&entry);
  81         return 0;
  82 }
  83
  84 /*
  85  * Try to remove the "submodule.<name>" section from .gitmodules where the given
  86  * path is configured. Return 0 only if a .gitmodules file was found, a section
  87  * with the correct path=<path> setting was found and we could remove it.
  88  */
  89 int remove_path_from_gitmodules(const char *path)
  90 {
  91         struct strbuf sect = STRBUF_INIT;
  92         const struct submodule *submodule;
  93
  94         if (!file_exists(".gitmodules")) /* Do nothing without .gitmodules */
  95                 return -1;
  96
  97         if (gitmodules_is_unmerged)
  98                 die(_("Cannot change unmerged .gitmodules, resolve merge conflicts first"));
  99
 100         submodule = submodule_from_path(null_sha1, path);
 101         if (!submodule || !submodule->name) {
 102                 warning(_("Could not find section in .gitmodules where path=%s"), path);
 103                 return -1;
 104         }
 105         strbuf_addstr(&sect, "submodule.");
 106         strbuf_addstr(&sect, submodule->name);
 107         if (git_config_rename_section_in_file(".gitmodules", sect.buf, NULL) < 0) {
 108                 /* Maybe the user already did that, don't error out here */
 109                 warning(_("Could not remove .gitmodules entry for %s"), path);
 110                 strbuf_release(&sect);
 111                 return -1;
 112         }
 113         strbuf_release(&sect);
 114         return 0;
 115 }
 116
 117 void stage_updated_gitmodules(void)
 118 {
 119         if (add_file_to_cache(".gitmodules", 0))
 120                 die(_("staging updated .gitmodules failed"));
 121 }
 122
 123 static int add_submodule_odb(const char *path)
 124 {
 125         struct strbuf objects_directory = STRBUF_INIT;
 126         struct alternate_object_database *alt_odb;
 127         int ret = 0;
 128         size_t alloc;
 129
 130         ret = strbuf_git_path_submodule(&objects_directory, path, "objects/");
 131         if (ret)
 132                 goto done;
 133         if (!is_directory(objects_directory.buf)) {
 134                 ret = -1;
 135                 goto done;
 136         }
 137         /* avoid adding it twice */
 138         prepare_alt_odb();
 139         for (alt_odb = alt_odb_list; alt_odb; alt_odb = alt_odb->next)
 140                 if (alt_odb->name - alt_odb->base == objects_directory.len &&
 141                                 !strncmp(alt_odb->base, objects_directory.buf,
 142                                         objects_directory.len))
 143                         goto done;
 144
 145         alloc = st_add(objects_directory.len, 42); /* for "12/345..." sha1 */
 146         alt_odb = xmalloc(st_add(sizeof(*alt_odb), alloc));
 147         alt_odb->next = alt_odb_list;
 148         xsnprintf(alt_odb->base, alloc, "%s", objects_directory.buf);
 149         alt_odb->name = alt_odb->base + objects_directory.len;
 150         alt_odb->name[2] = '/';
 151         alt_odb->name[40] = '\0';
 152         alt_odb->name[41] = '\0';
 153         alt_odb_list = alt_odb;
 154
 155         /* add possible alternates from the submodule */
 156         read_info_alternates(objects_directory.buf, 0);
 157 done:
 158         strbuf_release(&objects_directory);
 159         return ret;
 160 }
 161
 162 void set_diffopt_flags_from_submodule_config(struct diff_options *diffopt,
 163                                              const char *path)
 164 {
 165         const struct submodule *submodule = submodule_from_path(null_sha1, path);
 166         if (submodule) {
 167                 if (submodule->ignore)
 168                         handle_ignore_submodules_arg(diffopt, submodule->ignore);
 169                 else if (gitmodules_is_unmerged)
 170                         DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
 171         }
 172 }
 173
 174 int submodule_config(const char *var, const char *value, void *cb)
 175 {
 176         if (!strcmp(var, "submodule.fetchjobs")) {
 177                 parallel_jobs = git_config_int(var, value);
 178                 if (parallel_jobs < 0)
 179                         die(_("negative values not allowed for submodule.fetchJobs"));
 180                 return 0;
 181         } else if (starts_with(var, "submodule."))
 182                 return parse_submodule_config_option(var, value);
 183         else if (!strcmp(var, "fetch.recursesubmodules")) {
 184                 config_fetch_recurse_submodules = parse_fetch_recurse_submodules_arg(var, value);
 185                 return 0;
 186         }
 187         return 0;
 188 }
 189
 190 void gitmodules_config(void)
 191 {
 192         const char *work_tree = get_git_work_tree();
 193         if (work_tree) {
 194                 struct strbuf gitmodules_path = STRBUF_INIT;
 195                 int pos;
 196                 strbuf_addstr(&gitmodules_path, work_tree);
 197                 strbuf_addstr(&gitmodules_path, "/.gitmodules");
 198                 if (read_cache() < 0)
 199                         die("index file corrupt");
 200                 pos = cache_name_pos(".gitmodules", 11);
 201                 if (pos < 0) { /* .gitmodules not found or isn't merged */
 202                         pos = -1 - pos;
 203                         if (active_nr > pos) {  /* there is a .gitmodules */
 204                                 const struct cache_entry *ce = active_cache[pos];
 205                                 if (ce_namelen(ce) == 11 &&
 206                                     !memcmp(ce->name, ".gitmodules", 11))
 207                                         gitmodules_is_unmerged = 1;
 208                         }
 209                 } else if (pos < active_nr) {
 210                         struct stat st;
 211                         if (lstat(".gitmodules", &st) == 0 &&
 212                             ce_match_stat(active_cache[pos], &st, 0) & DATA_CHANGED)
 213                                 gitmodules_is_modified = 1;
 214                 }
 215
 216                 if (!gitmodules_is_unmerged)
 217                         git_config_from_file(submodule_config, gitmodules_path.buf, NULL);
 218                 strbuf_release(&gitmodules_path);
 219         }
 220 }
 221
 222 int parse_submodule_update_strategy(const char *value,
 223                 struct submodule_update_strategy *dst)
 224 {
 225         free((void*)dst->command);
 226         dst->command = NULL;
 227         if (!strcmp(value, "none"))
 228                 dst->type = SM_UPDATE_NONE;
 229         else if (!strcmp(value, "checkout"))
 230                 dst->type = SM_UPDATE_CHECKOUT;
 231         else if (!strcmp(value, "rebase"))
 232                 dst->type = SM_UPDATE_REBASE;
 233         else if (!strcmp(value, "merge"))
 234                 dst->type = SM_UPDATE_MERGE;
 235         else if (skip_prefix(value, "!", &value)) {
 236                 dst->type = SM_UPDATE_COMMAND;
 237                 dst->command = xstrdup(value);
 238         } else
 239                 return -1;
 240         return 0;
 241 }
 242
 243 const char *submodule_strategy_to_string(const struct submodule_update_strategy *s)
 244 {
 245         struct strbuf sb = STRBUF_INIT;
 246         switch (s->type) {
 247         case SM_UPDATE_CHECKOUT:
 248                 return "checkout";
 249         case SM_UPDATE_MERGE:
 250                 return "merge";
 251         case SM_UPDATE_REBASE:
 252                 return "rebase";
 253         case SM_UPDATE_NONE:
 254                 return "none";
 255         case SM_UPDATE_UNSPECIFIED:
 256                 return NULL;
 257         case SM_UPDATE_COMMAND:
 258                 strbuf_addf(&sb, "!%s", s->command);
 259                 return strbuf_detach(&sb, NULL);
 260         }
 261         return NULL;
 262 }
 263
 264 void handle_ignore_submodules_arg(struct diff_options *diffopt,
 265                                   const char *arg)
 266 {
 267         DIFF_OPT_CLR(diffopt, IGNORE_SUBMODULES);
 268         DIFF_OPT_CLR(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 269         DIFF_OPT_CLR(diffopt, IGNORE_DIRTY_SUBMODULES);
 270
 271         if (!strcmp(arg, "all"))
 272                 DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
 273         else if (!strcmp(arg, "untracked"))
 274                 DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 275         else if (!strcmp(arg, "dirty"))
 276                 DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES);
 277         else if (strcmp(arg, "none"))
 278                 die("bad --ignore-submodules argument: %s", arg);
 279 }
 280
 281 static int prepare_submodule_summary(struct rev_info *rev, const char *path,
 282                 struct commit *left, struct commit *right,
 283                 struct commit_list *merge_bases)
 284 {
 285         struct commit_list *list;
 286
 287         init_revisions(rev, NULL);
 288         setup_revisions(0, NULL, rev, NULL);
 289         rev->left_right = 1;
 290         rev->first_parent_only = 1;
 291         left->object.flags |= SYMMETRIC_LEFT;
 292         add_pending_object(rev, &left->object, path);
 293         add_pending_object(rev, &right->object, path);
 294         for (list = merge_bases; list; list = list->next) {
 295                 list->item->object.flags |= UNINTERESTING;
 296                 add_pending_object(rev, &list->item->object,
 297                         oid_to_hex(&list->item->object.oid));
 298         }
 299         return prepare_revision_walk(rev);
 300 }
 301
 302 static void print_submodule_summary(struct rev_info *rev, FILE *f,
 303                 const char *line_prefix,
 304                 const char *del, const char *add, const char *reset)
 305 {
 306         static const char format[] = "  %m %s";
 307         struct strbuf sb = STRBUF_INIT;
 308         struct commit *commit;
 309
 310         while ((commit = get_revision(rev))) {
 311                 struct pretty_print_context ctx = {0};
 312                 ctx.date_mode = rev->date_mode;
 313                 ctx.output_encoding = get_log_output_encoding();
 314                 strbuf_setlen(&sb, 0);
 315                 strbuf_addstr(&sb, line_prefix);
 316                 if (commit->object.flags & SYMMETRIC_LEFT) {
 317                         if (del)
 318                                 strbuf_addstr(&sb, del);
 319                 }
 320                 else if (add)
 321                         strbuf_addstr(&sb, add);
 322                 format_commit_message(commit, format, &sb, &ctx);
 323                 if (reset)
 324                         strbuf_addstr(&sb, reset);
 325                 strbuf_addch(&sb, '\n');
 326                 fprintf(f, "%s", sb.buf);
 327         }
 328         strbuf_release(&sb);
 329 }
 330
 331 /* Helper function to display the submodule header line prior to the full
 332  * summary output. If it can locate the submodule objects directory it will
 333  * attempt to lookup both the left and right commits and put them into the
 334  * left and right pointers.
 335  */
 336 static void show_submodule_header(FILE *f, const char *path,
 337                 const char *line_prefix,
 338                 struct object_id *one, struct object_id *two,
 339                 unsigned dirty_submodule, const char *meta,
 340                 const char *reset,
 341                 struct commit **left, struct commit **right,
 342                 struct commit_list **merge_bases)
 343 {
 344         const char *message = NULL;
 345         struct strbuf sb = STRBUF_INIT;
 346         int fast_forward = 0, fast_backward = 0;
 347
 348         if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
 349                 fprintf(f, "%sSubmodule %s contains untracked content\n",
 350                         line_prefix, path);
 351         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
 352                 fprintf(f, "%sSubmodule %s contains modified content\n",
 353                         line_prefix, path);
 354
 355         if (is_null_oid(one))
 356                 message = "(new submodule)";
 357         else if (is_null_oid(two))
 358                 message = "(submodule deleted)";
 359
 360         if (add_submodule_odb(path)) {
 361                 if (!message)
 362                         message = "(not initialized)";
 363                 goto output_header;
 364         }
 365
 366         /*
 367          * Attempt to lookup the commit references, and determine if this is
 368          * a fast forward or fast backwards update.
 369          */
 370         *left = lookup_commit_reference(one->hash);
 371         *right = lookup_commit_reference(two->hash);
 372
 373         /*
 374          * Warn about missing commits in the submodule project, but only if
 375          * they aren't null.
 376          */
 377         if ((!is_null_oid(one) && !*left) ||
 378              (!is_null_oid(two) && !*right))
 379                 message = "(commits not present)";
 380
 381         *merge_bases = get_merge_bases(*left, *right);
 382         if (*merge_bases) {
 383                 if ((*merge_bases)->item == *left)
 384                         fast_forward = 1;
 385                 else if ((*merge_bases)->item == *right)
 386                         fast_backward = 1;
 387         }
 388
 389         if (!oidcmp(one, two)) {
 390                 strbuf_release(&sb);
 391                 return;
 392         }
 393
 394 output_header:
 395         strbuf_addf(&sb, "%s%sSubmodule %s %s..", line_prefix, meta, path,
 396                         find_unique_abbrev(one->hash, DEFAULT_ABBREV));
 397         if (!fast_backward && !fast_forward)
 398                 strbuf_addch(&sb, '.');
 399         strbuf_add_unique_abbrev(&sb, two->hash, DEFAULT_ABBREV);
 400         if (message)
 401                 strbuf_addf(&sb, " %s%s\n", message, reset);
 402         else
 403                 strbuf_addf(&sb, "%s:%s\n", fast_backward ? " (rewind)" : "", reset);
 404         fwrite(sb.buf, sb.len, 1, f);
 405
 406         strbuf_release(&sb);
 407 }
 408
 409 void show_submodule_summary(FILE *f, const char *path,
 410                 const char *line_prefix,
 411                 struct object_id *one, struct object_id *two,
 412                 unsigned dirty_submodule, const char *meta,
 413                 const char *del, const char *add, const char *reset)
 414 {
 415         struct rev_info rev;
 416         struct commit *left = NULL, *right = NULL;
 417         struct commit_list *merge_bases = NULL;
 418
 419         show_submodule_header(f, path, line_prefix, one, two, dirty_submodule,
 420                               meta, reset, &left, &right, &merge_bases);
 421
 422         /*
 423          * If we don't have both a left and a right pointer, there is no
 424          * reason to try and display a summary. The header line should contain
 425          * all the information the user needs.
 426          */
 427         if (!left || !right)
 428                 goto out;
 429
 430         /* Treat revision walker failure the same as missing commits */
 431         if (prepare_submodule_summary(&rev, path, left, right, merge_bases)) {
 432                 fprintf(f, "%s(revision walker failed)\n", line_prefix);
 433                 goto out;
 434         }
 435
 436         print_submodule_summary(&rev, f, line_prefix, del, add, reset);
 437
 438 out:
 439         if (merge_bases)
 440                 free_commit_list(merge_bases);
 441         clear_commit_marks(left, ~0);
 442         clear_commit_marks(right, ~0);
 443 }
 444
 445 void show_submodule_inline_diff(FILE *f, const char *path,
 446                 const char *line_prefix,
 447                 struct object_id *one, struct object_id *two,
 448                 unsigned dirty_submodule, const char *meta,
 449                 const char *del, const char *add, const char *reset,
 450                 const struct diff_options *o)
 451 {
 452         const struct object_id *old = &empty_tree_oid, *new = &empty_tree_oid;
 453         struct commit *left = NULL, *right = NULL;
 454         struct commit_list *merge_bases = NULL;
 455         struct strbuf submodule_dir = STRBUF_INIT;
 456         struct child_process cp = CHILD_PROCESS_INIT;
 457
 458         show_submodule_header(f, path, line_prefix, one, two, dirty_submodule,
 459                               meta, reset, &left, &right, &merge_bases);
 460
 461         /* We need a valid left and right commit to display a difference */
 462         if (!(left || is_null_oid(one)) ||
 463             !(right || is_null_oid(two)))
 464                 goto done;
 465
 466         if (left)
 467                 old = one;
 468         if (right)
 469                 new = two;
 470
 471         fflush(f);
 472         cp.git_cmd = 1;
 473         cp.dir = path;
 474         cp.out = dup(fileno(f));
 475         cp.no_stdin = 1;
 476
 477         /* TODO: other options may need to be passed here. */
 478         argv_array_push(&cp.args, "diff");
 479         argv_array_pushf(&cp.args, "--line-prefix=%s", line_prefix);
 480         if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
 481                 argv_array_pushf(&cp.args, "--src-prefix=%s%s/",
 482                                  o->b_prefix, path);
 483                 argv_array_pushf(&cp.args, "--dst-prefix=%s%s/",
 484                                  o->a_prefix, path);
 485         } else {
 486                 argv_array_pushf(&cp.args, "--src-prefix=%s%s/",
 487                                  o->a_prefix, path);
 488                 argv_array_pushf(&cp.args, "--dst-prefix=%s%s/",
 489                                  o->b_prefix, path);
 490         }
 491         argv_array_push(&cp.args, oid_to_hex(old));
 492         /*
 493          * If the submodule has modified content, we will diff against the
 494          * work tree, under the assumption that the user has asked for the
 495          * diff format and wishes to actually see all differences even if they
 496          * haven't yet been committed to the submodule yet.
 497          */
 498         if (!(dirty_submodule & DIRTY_SUBMODULE_MODIFIED))
 499                 argv_array_push(&cp.args, oid_to_hex(new));
 500
 501         if (run_command(&cp))
 502                 fprintf(f, "(diff failed)\n");
 503
 504 done:
 505         strbuf_release(&submodule_dir);
 506         if (merge_bases)
 507                 free_commit_list(merge_bases);
 508         if (left)
 509                 clear_commit_marks(left, ~0);
 510         if (right)
 511                 clear_commit_marks(right, ~0);
 512 }
 513
 514 void set_config_fetch_recurse_submodules(int value)
 515 {
 516         config_fetch_recurse_submodules = value;
 517 }
 518
 519 static int has_remote(const char *refname, const struct object_id *oid,
 520                       int flags, void *cb_data)
 521 {
 522         return 1;
 523 }
 524
 525 static int append_sha1_to_argv(const unsigned char sha1[20], void *data)
 526 {
 527         struct argv_array *argv = data;
 528         argv_array_push(argv, sha1_to_hex(sha1));
 529         return 0;
 530 }
 531
 532 static int check_has_commit(const unsigned char sha1[20], void *data)
 533 {
 534         int *has_commit = data;
 535
 536         if (!lookup_commit_reference(sha1))
 537                 *has_commit = 0;
 538
 539         return 0;
 540 }
 541
 542 static int submodule_has_commits(const char *path, struct sha1_array *commits)
 543 {
 544         int has_commit = 1;
 545
 546         if (add_submodule_odb(path))
 547                 return 0;
 548
 549         sha1_array_for_each_unique(commits, check_has_commit, &has_commit);
 550         return has_commit;
 551 }
 552
 553 static int submodule_needs_pushing(const char *path, struct sha1_array *commits)
 554 {
 555         if (!submodule_has_commits(path, commits))
 556                 /*
 557                  * NOTE: We do consider it safe to return "no" here. The
 558                  * correct answer would be "We do not know" instead of
 559                  * "No push needed", but it is quite hard to change
 560                  * the submodule pointer without having the submodule
 561                  * around. If a user did however change the submodules
 562                  * without having the submodule around, this indicates
 563                  * an expert who knows what they are doing or a
 564                  * maintainer integrating work from other people. In
 565                  * both cases it should be safe to skip this check.
 566                  */
 567                 return 0;
 568
 569         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 570                 struct child_process cp = CHILD_PROCESS_INIT;
 571                 struct strbuf buf = STRBUF_INIT;
 572                 int needs_pushing = 0;
 573
 574                 argv_array_push(&cp.args, "rev-list");
 575                 sha1_array_for_each_unique(commits, append_sha1_to_argv, &cp.args);
 576                 argv_array_pushl(&cp.args, "--not", "--remotes", "-n", "1" , NULL);
 577
 578                 prepare_submodule_repo_env(&cp.env_array);
 579                 cp.git_cmd = 1;
 580                 cp.no_stdin = 1;
 581                 cp.out = -1;
 582                 cp.dir = path;
 583                 if (start_command(&cp))
 584                         die("Could not run 'git rev-list <commits> --not --remotes -n 1' command in submodule %s",
 585                                         path);
 586                 if (strbuf_read(&buf, cp.out, 41))
 587                         needs_pushing = 1;
 588                 finish_command(&cp);
 589                 close(cp.out);
 590                 strbuf_release(&buf);
 591                 return needs_pushing;
 592         }
 593
 594         return 0;
 595 }
 596
 597 static struct sha1_array *submodule_commits(struct string_list *submodules,
 598                                             const char *path)
 599 {
 600         struct string_list_item *item;
 601
 602         item = string_list_insert(submodules, path);
 603         if (item->util)
 604                 return (struct sha1_array *) item->util;
 605
 606         /* NEEDSWORK: should we have sha1_array_init()? */
 607         item->util = xcalloc(1, sizeof(struct sha1_array));
 608         return (struct sha1_array *) item->util;
 609 }
 610
 611 static void collect_submodules_from_diff(struct diff_queue_struct *q,
 612                                          struct diff_options *options,
 613                                          void *data)
 614 {
 615         int i;
 616         struct string_list *submodules = data;
 617
 618         for (i = 0; i < q->nr; i++) {
 619                 struct diff_filepair *p = q->queue[i];
 620                 struct sha1_array *commits;
 621                 if (!S_ISGITLINK(p->two->mode))
 622                         continue;
 623                 commits = submodule_commits(submodules, p->two->path);
 624                 sha1_array_append(commits, p->two->oid.hash);
 625         }
 626 }
 627
 628 static void find_unpushed_submodule_commits(struct commit *commit,
 629                 struct string_list *needs_pushing)
 630 {
 631         struct rev_info rev;
 632
 633         init_revisions(&rev, NULL);
 634         rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
 635         rev.diffopt.format_callback = collect_submodules_from_diff;
 636         rev.diffopt.format_callback_data = needs_pushing;
 637         diff_tree_combined_merge(commit, 1, &rev);
 638 }
 639
 640 static void free_submodules_sha1s(struct string_list *submodules)
 641 {
 642         struct string_list_item *item;
 643         for_each_string_list_item(item, submodules)
 644                 sha1_array_clear((struct sha1_array *) item->util);
 645         string_list_clear(submodules, 1);
 646 }
 647
 648 int find_unpushed_submodules(struct sha1_array *commits,
 649                 const char *remotes_name, struct string_list *needs_pushing)
 650 {
 651         struct rev_info rev;
 652         struct commit *commit;
 653         struct string_list submodules = STRING_LIST_INIT_DUP;
 654         struct string_list_item *submodule;
 655         struct argv_array argv = ARGV_ARRAY_INIT;
 656
 657         init_revisions(&rev, NULL);
 658
 659         /* argv.argv[0] will be ignored by setup_revisions */
 660         argv_array_push(&argv, "find_unpushed_submodules");
 661         sha1_array_for_each_unique(commits, append_sha1_to_argv, &argv);
 662         argv_array_push(&argv, "--not");
 663         argv_array_pushf(&argv, "--remotes=%s", remotes_name);
 664
 665         setup_revisions(argv.argc, argv.argv, &rev, NULL);
 666         if (prepare_revision_walk(&rev))
 667                 die("revision walk setup failed");
 668
 669         while ((commit = get_revision(&rev)) != NULL)
 670                 find_unpushed_submodule_commits(commit, &submodules);
 671
 672         reset_revision_walk();
 673         argv_array_clear(&argv);
 674
 675         for_each_string_list_item(submodule, &submodules) {
 676                 struct sha1_array *commits = (struct sha1_array *) submodule->util;
 677
 678                 if (submodule_needs_pushing(submodule->string, commits))
 679                         string_list_insert(needs_pushing, submodule->string);
 680         }
 681         free_submodules_sha1s(&submodules);
 682
 683         return needs_pushing->nr;
 684 }
 685
 686 static int push_submodule(const char *path)
 687 {
 688         if (add_submodule_odb(path))
 689                 return 1;
 690
 691         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 692                 struct child_process cp = CHILD_PROCESS_INIT;
 693                 const char *argv[] = {"push", NULL};
 694
 695                 cp.argv = argv;
 696                 prepare_submodule_repo_env(&cp.env_array);
 697                 cp.git_cmd = 1;
 698                 cp.no_stdin = 1;
 699                 cp.dir = path;
 700                 if (run_command(&cp))
 701                         return 0;
 702                 close(cp.out);
 703         }
 704
 705         return 1;
 706 }
 707
 708 int push_unpushed_submodules(struct sha1_array *commits, const char *remotes_name)
 709 {
 710         int i, ret = 1;
 711         struct string_list needs_pushing = STRING_LIST_INIT_DUP;
 712
 713         if (!find_unpushed_submodules(commits, remotes_name, &needs_pushing))
 714                 return 1;
 715
 716         for (i = 0; i < needs_pushing.nr; i++) {
 717                 const char *path = needs_pushing.items[i].string;
 718                 fprintf(stderr, "Pushing submodule '%s'\n", path);
 719                 if (!push_submodule(path)) {
 720                         fprintf(stderr, "Unable to push submodule '%s'\n", path);
 721                         ret = 0;
 722                 }
 723         }
 724
 725         string_list_clear(&needs_pushing, 0);
 726
 727         return ret;
 728 }
 729
 730 static int is_submodule_commit_present(const char *path, unsigned char sha1[20])
 731 {
 732         int is_present = 0;
 733         if (!add_submodule_odb(path) && lookup_commit_reference(sha1)) {
 734                 /* Even if the submodule is checked out and the commit is
 735                  * present, make sure it is reachable from a ref. */
 736                 struct child_process cp = CHILD_PROCESS_INIT;
 737                 const char *argv[] = {"rev-list", "-n", "1", NULL, "--not", "--all", NULL};
 738                 struct strbuf buf = STRBUF_INIT;
 739
 740                 argv[3] = sha1_to_hex(sha1);
 741                 cp.argv = argv;
 742                 prepare_submodule_repo_env(&cp.env_array);
 743                 cp.git_cmd = 1;
 744                 cp.no_stdin = 1;
 745                 cp.dir = path;
 746                 if (!capture_command(&cp, &buf, 1024) && !buf.len)
 747                         is_present = 1;
 748
 749                 strbuf_release(&buf);
 750         }
 751         return is_present;
 752 }
 753
 754 static void submodule_collect_changed_cb(struct diff_queue_struct *q,
 755                                          struct diff_options *options,
 756                                          void *data)
 757 {
 758         int i;
 759         for (i = 0; i < q->nr; i++) {
 760                 struct diff_filepair *p = q->queue[i];
 761                 if (!S_ISGITLINK(p->two->mode))
 762                         continue;
 763
 764                 if (S_ISGITLINK(p->one->mode)) {
 765                         /* NEEDSWORK: We should honor the name configured in
 766                          * the .gitmodules file of the commit we are examining
 767                          * here to be able to correctly follow submodules
 768                          * being moved around. */
 769                         struct string_list_item *path;
 770                         path = unsorted_string_list_lookup(&changed_submodule_paths, p->two->path);
 771                         if (!path && !is_submodule_commit_present(p->two->path, p->two->oid.hash))
 772                                 string_list_append(&changed_submodule_paths, xstrdup(p->two->path));
 773                 } else {
 774                         /* Submodule is new or was moved here */
 775                         /* NEEDSWORK: When the .git directories of submodules
 776                          * live inside the superprojects .git directory some
 777                          * day we should fetch new submodules directly into
 778                          * that location too when config or options request
 779                          * that so they can be checked out from there. */
 780                         continue;
 781                 }
 782         }
 783 }
 784
 785 static int add_sha1_to_array(const char *ref, const struct object_id *oid,
 786                              int flags, void *data)
 787 {
 788         sha1_array_append(data, oid->hash);
 789         return 0;
 790 }
 791
 792 void check_for_new_submodule_commits(unsigned char new_sha1[20])
 793 {
 794         if (!initialized_fetch_ref_tips) {
 795                 for_each_ref(add_sha1_to_array, &ref_tips_before_fetch);
 796                 initialized_fetch_ref_tips = 1;
 797         }
 798
 799         sha1_array_append(&ref_tips_after_fetch, new_sha1);
 800 }
 801
 802 static int add_sha1_to_argv(const unsigned char sha1[20], void *data)
 803 {
 804         argv_array_push(data, sha1_to_hex(sha1));
 805         return 0;
 806 }
 807
 808 static void calculate_changed_submodule_paths(void)
 809 {
 810         struct rev_info rev;
 811         struct commit *commit;
 812         struct argv_array argv = ARGV_ARRAY_INIT;
 813
 814         /* No need to check if there are no submodules configured */
 815         if (!submodule_from_path(NULL, NULL))
 816                 return;
 817
 818         init_revisions(&rev, NULL);
 819         argv_array_push(&argv, "--"); /* argv[0] program name */
 820         sha1_array_for_each_unique(&ref_tips_after_fetch,
 821                                    add_sha1_to_argv, &argv);
 822         argv_array_push(&argv, "--not");
 823         sha1_array_for_each_unique(&ref_tips_before_fetch,
 824                                    add_sha1_to_argv, &argv);
 825         setup_revisions(argv.argc, argv.argv, &rev, NULL);
 826         if (prepare_revision_walk(&rev))
 827                 die("revision walk setup failed");
 828
 829         /*
 830          * Collect all submodules (whether checked out or not) for which new
 831          * commits have been recorded upstream in "changed_submodule_paths".
 832          */
 833         while ((commit = get_revision(&rev))) {
 834                 struct commit_list *parent = commit->parents;
 835                 while (parent) {
 836                         struct diff_options diff_opts;
 837                         diff_setup(&diff_opts);
 838                         DIFF_OPT_SET(&diff_opts, RECURSIVE);
 839                         diff_opts.output_format |= DIFF_FORMAT_CALLBACK;
 840                         diff_opts.format_callback = submodule_collect_changed_cb;
 841                         diff_setup_done(&diff_opts);
 842                         diff_tree_sha1(parent->item->object.oid.hash, commit->object.oid.hash, "", &diff_opts);
 843                         diffcore_std(&diff_opts);
 844                         diff_flush(&diff_opts);
 845                         parent = parent->next;
 846                 }
 847         }
 848
 849         argv_array_clear(&argv);
 850         sha1_array_clear(&ref_tips_before_fetch);
 851         sha1_array_clear(&ref_tips_after_fetch);
 852         initialized_fetch_ref_tips = 0;
 853 }
 854
 855 struct submodule_parallel_fetch {
 856         int count;
 857         struct argv_array args;
 858         const char *work_tree;
 859         const char *prefix;
 860         int command_line_option;
 861         int quiet;
 862         int result;
 863 };
 864 #define SPF_INIT {0, ARGV_ARRAY_INIT, NULL, NULL, 0, 0, 0}
 865
 866 static int get_next_submodule(struct child_process *cp,
 867                               struct strbuf *err, void *data, void **task_cb)
 868 {
 869         int ret = 0;
 870         struct submodule_parallel_fetch *spf = data;
 871
 872         for (; spf->count < active_nr; spf->count++) {
 873                 struct strbuf submodule_path = STRBUF_INIT;
 874                 struct strbuf submodule_git_dir = STRBUF_INIT;
 875                 struct strbuf submodule_prefix = STRBUF_INIT;
 876                 const struct cache_entry *ce = active_cache[spf->count];
 877                 const char *git_dir, *default_argv;
 878                 const struct submodule *submodule;
 879
 880                 if (!S_ISGITLINK(ce->ce_mode))
 881                         continue;
 882
 883                 submodule = submodule_from_path(null_sha1, ce->name);
 884                 if (!submodule)
 885                         submodule = submodule_from_name(null_sha1, ce->name);
 886
 887                 default_argv = "yes";
 888                 if (spf->command_line_option == RECURSE_SUBMODULES_DEFAULT) {
 889                         if (submodule &&
 890                             submodule->fetch_recurse !=
 891                                                 RECURSE_SUBMODULES_NONE) {
 892                                 if (submodule->fetch_recurse ==
 893                                                 RECURSE_SUBMODULES_OFF)
 894                                         continue;
 895                                 if (submodule->fetch_recurse ==
 896                                                 RECURSE_SUBMODULES_ON_DEMAND) {
 897                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 898                                                 continue;
 899                                         default_argv = "on-demand";
 900                                 }
 901                         } else {
 902                                 if ((config_fetch_recurse_submodules == RECURSE_SUBMODULES_OFF) ||
 903                                     gitmodules_is_unmerged)
 904                                         continue;
 905                                 if (config_fetch_recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) {
 906                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 907                                                 continue;
 908                                         default_argv = "on-demand";
 909                                 }
 910                         }
 911                 } else if (spf->command_line_option == RECURSE_SUBMODULES_ON_DEMAND) {
 912                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 913                                 continue;
 914                         default_argv = "on-demand";
 915                 }
 916
 917                 strbuf_addf(&submodule_path, "%s/%s", spf->work_tree, ce->name);
 918                 strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
 919                 strbuf_addf(&submodule_prefix, "%s%s/", spf->prefix, ce->name);
 920                 git_dir = read_gitfile(submodule_git_dir.buf);
 921                 if (!git_dir)
 922                         git_dir = submodule_git_dir.buf;
 923                 if (is_directory(git_dir)) {
 924                         child_process_init(cp);
 925                         cp->dir = strbuf_detach(&submodule_path, NULL);
 926                         prepare_submodule_repo_env(&cp->env_array);
 927                         cp->git_cmd = 1;
 928                         if (!spf->quiet)
 929                                 strbuf_addf(err, "Fetching submodule %s%s\n",
 930                                             spf->prefix, ce->name);
 931                         argv_array_init(&cp->args);
 932                         argv_array_pushv(&cp->args, spf->args.argv);
 933                         argv_array_push(&cp->args, default_argv);
 934                         argv_array_push(&cp->args, "--submodule-prefix");
 935                         argv_array_push(&cp->args, submodule_prefix.buf);
 936                         ret = 1;
 937                 }
 938                 strbuf_release(&submodule_path);
 939                 strbuf_release(&submodule_git_dir);
 940                 strbuf_release(&submodule_prefix);
 941                 if (ret) {
 942                         spf->count++;
 943                         return 1;
 944                 }
 945         }
 946         return 0;
 947 }
 948
 949 static int fetch_start_failure(struct strbuf *err,
 950                                void *cb, void *task_cb)
 951 {
 952         struct submodule_parallel_fetch *spf = cb;
 953
 954         spf->result = 1;
 955
 956         return 0;
 957 }
 958
 959 static int fetch_finish(int retvalue, struct strbuf *err,
 960                         void *cb, void *task_cb)
 961 {
 962         struct submodule_parallel_fetch *spf = cb;
 963
 964         if (retvalue)
 965                 spf->result = 1;
 966
 967         return 0;
 968 }
 969
 970 int fetch_populated_submodules(const struct argv_array *options,
 971                                const char *prefix, int command_line_option,
 972                                int quiet, int max_parallel_jobs)
 973 {
 974         int i;
 975         struct submodule_parallel_fetch spf = SPF_INIT;
 976
 977         spf.work_tree = get_git_work_tree();
 978         spf.command_line_option = command_line_option;
 979         spf.quiet = quiet;
 980         spf.prefix = prefix;
 981
 982         if (!spf.work_tree)
 983                 goto out;
 984
 985         if (read_cache() < 0)
 986                 die("index file corrupt");
 987
 988         argv_array_push(&spf.args, "fetch");
 989         for (i = 0; i < options->argc; i++)
 990                 argv_array_push(&spf.args, options->argv[i]);
 991         argv_array_push(&spf.args, "--recurse-submodules-default");
 992         /* default value, "--submodule-prefix" and its value are added later */
 993
 994         if (max_parallel_jobs < 0)
 995                 max_parallel_jobs = parallel_jobs;
 996
 997         calculate_changed_submodule_paths();
 998         run_processes_parallel(max_parallel_jobs,
 999                                get_next_submodule,
1000                                fetch_start_failure,
1001                                fetch_finish,
1002                                &spf);
1003
1004         argv_array_clear(&spf.args);
1005 out:
1006         string_list_clear(&changed_submodule_paths, 1);
1007         return spf.result;
1008 }
1009
1010 unsigned is_submodule_modified(const char *path, int ignore_untracked)
1011 {
1012         ssize_t len;
1013         struct child_process cp = CHILD_PROCESS_INIT;
1014         const char *argv[] = {
1015                 "status",
1016                 "--porcelain",
1017                 NULL,
1018                 NULL,
1019         };
1020         struct strbuf buf = STRBUF_INIT;
1021         unsigned dirty_submodule = 0;
1022         const char *line, *next_line;
1023         const char *git_dir;
1024
1025         strbuf_addf(&buf, "%s/.git", path);
1026         git_dir = read_gitfile(buf.buf);
1027         if (!git_dir)
1028                 git_dir = buf.buf;
1029         if (!is_directory(git_dir)) {
1030                 strbuf_release(&buf);
1031                 /* The submodule is not checked out, so it is not modified */
1032                 return 0;
1033
1034         }
1035         strbuf_reset(&buf);
1036
1037         if (ignore_untracked)
1038                 argv[2] = "-uno";
1039
1040         cp.argv = argv;
1041         prepare_submodule_repo_env(&cp.env_array);
1042         cp.git_cmd = 1;
1043         cp.no_stdin = 1;
1044         cp.out = -1;
1045         cp.dir = path;
1046         if (start_command(&cp))
1047                 die("Could not run 'git status --porcelain' in submodule %s", path);
1048
1049         len = strbuf_read(&buf, cp.out, 1024);
1050         line = buf.buf;
1051         while (len > 2) {
1052                 if ((line[0] == '?') && (line[1] == '?')) {
1053                         dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
1054                         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
1055                                 break;
1056                 } else {
1057                         dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
1058                         if (ignore_untracked ||
1059                             (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED))
1060                                 break;
1061                 }
1062                 next_line = strchr(line, '\n');
1063                 if (!next_line)
1064                         break;
1065                 next_line++;
1066                 len -= (next_line - line);
1067                 line = next_line;
1068         }
1069         close(cp.out);
1070
1071         if (finish_command(&cp))
1072                 die("'git status --porcelain' failed in submodule %s", path);
1073
1074         strbuf_release(&buf);
1075         return dirty_submodule;
1076 }
1077
1078 int submodule_uses_gitfile(const char *path)
1079 {
1080         struct child_process cp = CHILD_PROCESS_INIT;
1081         const char *argv[] = {
1082                 "submodule",
1083                 "foreach",
1084                 "--quiet",
1085                 "--recursive",
1086                 "test -f .git",
1087                 NULL,
1088         };
1089         struct strbuf buf = STRBUF_INIT;
1090         const char *git_dir;
1091
1092         strbuf_addf(&buf, "%s/.git", path);
1093         git_dir = read_gitfile(buf.buf);
1094         if (!git_dir) {
1095                 strbuf_release(&buf);
1096                 return 0;
1097         }
1098         strbuf_release(&buf);
1099
1100         /* Now test that all nested submodules use a gitfile too */
1101         cp.argv = argv;
1102         prepare_submodule_repo_env(&cp.env_array);
1103         cp.git_cmd = 1;
1104         cp.no_stdin = 1;
1105         cp.no_stderr = 1;
1106         cp.no_stdout = 1;
1107         cp.dir = path;
1108         if (run_command(&cp))
1109                 return 0;
1110
1111         return 1;
1112 }
1113
1114 int ok_to_remove_submodule(const char *path)
1115 {
1116         ssize_t len;
1117         struct child_process cp = CHILD_PROCESS_INIT;
1118         const char *argv[] = {
1119                 "status",
1120                 "--porcelain",
1121                 "-u",
1122                 "--ignore-submodules=none",
1123                 NULL,
1124         };
1125         struct strbuf buf = STRBUF_INIT;
1126         int ok_to_remove = 1;
1127
1128         if (!file_exists(path) || is_empty_dir(path))
1129                 return 1;
1130
1131         if (!submodule_uses_gitfile(path))
1132                 return 0;
1133
1134         cp.argv = argv;
1135         prepare_submodule_repo_env(&cp.env_array);
1136         cp.git_cmd = 1;
1137         cp.no_stdin = 1;
1138         cp.out = -1;
1139         cp.dir = path;
1140         if (start_command(&cp))
1141                 die("Could not run 'git status --porcelain -uall --ignore-submodules=none' in submodule %s", path);
1142
1143         len = strbuf_read(&buf, cp.out, 1024);
1144         if (len > 2)
1145                 ok_to_remove = 0;
1146         close(cp.out);
1147
1148         if (finish_command(&cp))
1149                 die("'git status --porcelain -uall --ignore-submodules=none' failed in submodule %s", path);
1150
1151         strbuf_release(&buf);
1152         return ok_to_remove;
1153 }
1154
1155 static int find_first_merges(struct object_array *result, const char *path,
1156                 struct commit *a, struct commit *b)
1157 {
1158         int i, j;
1159         struct object_array merges = OBJECT_ARRAY_INIT;
1160         struct commit *commit;
1161         int contains_another;
1162
1163         char merged_revision[42];
1164         const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
1165                                    "--all", merged_revision, NULL };
1166         struct rev_info revs;
1167         struct setup_revision_opt rev_opts;
1168
1169         memset(result, 0, sizeof(struct object_array));
1170         memset(&rev_opts, 0, sizeof(rev_opts));
1171
1172         /* get all revisions that merge commit a */
1173         snprintf(merged_revision, sizeof(merged_revision), "^%s",
1174                         oid_to_hex(&a->object.oid));
1175         init_revisions(&revs, NULL);
1176         rev_opts.submodule = path;
1177         setup_revisions(ARRAY_SIZE(rev_args)-1, rev_args, &revs, &rev_opts);
1178
1179         /* save all revisions from the above list that contain b */
1180         if (prepare_revision_walk(&revs))
1181                 die("revision walk setup failed");
1182         while ((commit = get_revision(&revs)) != NULL) {
1183                 struct object *o = &(commit->object);
1184                 if (in_merge_bases(b, commit))
1185                         add_object_array(o, NULL, &merges);
1186         }
1187         reset_revision_walk();
1188
1189         /* Now we've got all merges that contain a and b. Prune all
1190          * merges that contain another found merge and save them in
1191          * result.
1192          */
1193         for (i = 0; i < merges.nr; i++) {
1194                 struct commit *m1 = (struct commit *) merges.objects[i].item;
1195
1196                 contains_another = 0;
1197                 for (j = 0; j < merges.nr; j++) {
1198                         struct commit *m2 = (struct commit *) merges.objects[j].item;
1199                         if (i != j && in_merge_bases(m2, m1)) {
1200                                 contains_another = 1;
1201                                 break;
1202                         }
1203                 }
1204
1205                 if (!contains_another)
1206                         add_object_array(merges.objects[i].item, NULL, result);
1207         }
1208
1209         free(merges.objects);
1210         return result->nr;
1211 }
1212
1213 static void print_commit(struct commit *commit)
1214 {
1215         struct strbuf sb = STRBUF_INIT;
1216         struct pretty_print_context ctx = {0};
1217         ctx.date_mode.type = DATE_NORMAL;
1218         format_commit_message(commit, " %h: %m %s", &sb, &ctx);
1219         fprintf(stderr, "%s\n", sb.buf);
1220         strbuf_release(&sb);
1221 }
1222
1223 #define MERGE_WARNING(path, msg) \
1224         warning("Failed to merge submodule %s (%s)", path, msg);
1225
1226 int merge_submodule(unsigned char result[20], const char *path,
1227                     const unsigned char base[20], const unsigned char a[20],
1228                     const unsigned char b[20], int search)
1229 {
1230         struct commit *commit_base, *commit_a, *commit_b;
1231         int parent_count;
1232         struct object_array merges;
1233
1234         int i;
1235
1236         /* store a in result in case we fail */
1237         hashcpy(result, a);
1238
1239         /* we can not handle deletion conflicts */
1240         if (is_null_sha1(base))
1241                 return 0;
1242         if (is_null_sha1(a))
1243                 return 0;
1244         if (is_null_sha1(b))
1245                 return 0;
1246
1247         if (add_submodule_odb(path)) {
1248                 MERGE_WARNING(path, "not checked out");
1249                 return 0;
1250         }
1251
1252         if (!(commit_base = lookup_commit_reference(base)) ||
1253             !(commit_a = lookup_commit_reference(a)) ||
1254             !(commit_b = lookup_commit_reference(b))) {
1255                 MERGE_WARNING(path, "commits not present");
1256                 return 0;
1257         }
1258
1259         /* check whether both changes are forward */
1260         if (!in_merge_bases(commit_base, commit_a) ||
1261             !in_merge_bases(commit_base, commit_b)) {
1262                 MERGE_WARNING(path, "commits don't follow merge-base");
1263                 return 0;
1264         }
1265
1266         /* Case #1: a is contained in b or vice versa */
1267         if (in_merge_bases(commit_a, commit_b)) {
1268                 hashcpy(result, b);
1269                 return 1;
1270         }
1271         if (in_merge_bases(commit_b, commit_a)) {
1272                 hashcpy(result, a);
1273                 return 1;
1274         }
1275
1276         /*
1277          * Case #2: There are one or more merges that contain a and b in
1278          * the submodule. If there is only one, then present it as a
1279          * suggestion to the user, but leave it marked unmerged so the
1280          * user needs to confirm the resolution.
1281          */
1282
1283         /* Skip the search if makes no sense to the calling context.  */
1284         if (!search)
1285                 return 0;
1286
1287         /* find commit which merges them */
1288         parent_count = find_first_merges(&merges, path, commit_a, commit_b);
1289         switch (parent_count) {
1290         case 0:
1291                 MERGE_WARNING(path, "merge following commits not found");
1292                 break;
1293
1294         case 1:
1295                 MERGE_WARNING(path, "not fast-forward");
1296                 fprintf(stderr, "Found a possible merge resolution "
1297                                 "for the submodule:\n");
1298                 print_commit((struct commit *) merges.objects[0].item);
1299                 fprintf(stderr,
1300                         "If this is correct simply add it to the index "
1301                         "for example\n"
1302                         "by using:\n\n"
1303                         "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1304                         "which will accept this suggestion.\n",
1305                         oid_to_hex(&merges.objects[0].item->oid), path);
1306                 break;
1307
1308         default:
1309                 MERGE_WARNING(path, "multiple merges found");
1310                 for (i = 0; i < merges.nr; i++)
1311                         print_commit((struct commit *) merges.objects[i].item);
1312         }
1313
1314         free(merges.objects);
1315         return 0;
1316 }
1317
1318 /* Update gitfile and core.worktree setting to connect work tree and git dir */
1319 void connect_work_tree_and_git_dir(const char *work_tree, const char *git_dir)
1320 {
1321         struct strbuf file_name = STRBUF_INIT;
1322         struct strbuf rel_path = STRBUF_INIT;
1323         const char *real_work_tree = xstrdup(real_path(work_tree));
1324
1325         /* Update gitfile */
1326         strbuf_addf(&file_name, "%s/.git", work_tree);
1327         write_file(file_name.buf, "gitdir: %s",
1328                    relative_path(git_dir, real_work_tree, &rel_path));
1329
1330         /* Update core.worktree setting */
1331         strbuf_reset(&file_name);
1332         strbuf_addf(&file_name, "%s/config", git_dir);
1333         git_config_set_in_file(file_name.buf, "core.worktree",
1334                                relative_path(real_work_tree, git_dir,
1335                                              &rel_path));
1336
1337         strbuf_release(&file_name);
1338         strbuf_release(&rel_path);
1339         free((void *)real_work_tree);
1340 }
1341
1342 int parallel_submodules(void)
1343 {
1344         return parallel_jobs;
1345 }
1346
1347 void prepare_submodule_repo_env(struct argv_array *out)
1348 {
1349         const char * const *var;
1350
1351         for (var = local_repo_env; *var; var++) {
1352                 if (strcmp(*var, CONFIG_DATA_ENVIRONMENT))
1353                         argv_array_push(out, *var);
1354         }
1355         argv_array_push(out, "GIT_DIR=.git");
1356 }