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

   1 #include "cache.h"
   2 #include "repository.h"
   3 #include "config.h"
   4 #include "submodule-config.h"
   5 #include "submodule.h"
   6 #include "dir.h"
   7 #include "diff.h"
   8 #include "commit.h"
   9 #include "revision.h"
  10 #include "run-command.h"
  11 #include "diffcore.h"
  12 #include "refs.h"
  13 #include "string-list.h"
  14 #include "sha1-array.h"
  15 #include "argv-array.h"
  16 #include "blob.h"
  17 #include "thread-utils.h"
  18 #include "quote.h"
  19 #include "remote.h"
  20 #include "worktree.h"
  21 #include "parse-options.h"
  22
  23 static int config_update_recurse_submodules = RECURSE_SUBMODULES_OFF;
  24 static struct string_list changed_submodule_paths = STRING_LIST_INIT_DUP;
  25 static int initialized_fetch_ref_tips;
  26 static struct oid_array ref_tips_before_fetch;
  27 static struct oid_array ref_tips_after_fetch;
  28
  29 /*
  30  * Check if the .gitmodules file is unmerged. Parsing of the .gitmodules file
  31  * will be disabled because we can't guess what might be configured in
  32  * .gitmodules unless the user resolves the conflict.
  33  */
  34 int is_gitmodules_unmerged(const struct index_state *istate)
  35 {
  36         int pos = index_name_pos(istate, GITMODULES_FILE, strlen(GITMODULES_FILE));
  37         if (pos < 0) { /* .gitmodules not found or isn't merged */
  38                 pos = -1 - pos;
  39                 if (istate->cache_nr > pos) {  /* there is a .gitmodules */
  40                         const struct cache_entry *ce = istate->cache[pos];
  41                         if (ce_namelen(ce) == strlen(GITMODULES_FILE) &&
  42                             !strcmp(ce->name, GITMODULES_FILE))
  43                                 return 1;
  44                 }
  45         }
  46
  47         return 0;
  48 }
  49
  50 /*
  51  * Check if the .gitmodules file has unstaged modifications.  This must be
  52  * checked before allowing modifications to the .gitmodules file with the
  53  * intention to stage them later, because when continuing we would stage the
  54  * modifications the user didn't stage herself too. That might change in a
  55  * future version when we learn to stage the changes we do ourselves without
  56  * staging any previous modifications.
  57  */
  58 int is_staging_gitmodules_ok(const struct index_state *istate)
  59 {
  60         int pos = index_name_pos(istate, GITMODULES_FILE, strlen(GITMODULES_FILE));
  61
  62         if ((pos >= 0) && (pos < istate->cache_nr)) {
  63                 struct stat st;
  64                 if (lstat(GITMODULES_FILE, &st) == 0 &&
  65                     ce_match_stat(istate->cache[pos], &st, 0) & DATA_CHANGED)
  66                         return 0;
  67         }
  68
  69         return 1;
  70 }
  71
  72 /*
  73  * Try to update the "path" entry in the "submodule.<name>" section of the
  74  * .gitmodules file. Return 0 only if a .gitmodules file was found, a section
  75  * with the correct path=<oldpath> setting was found and we could update it.
  76  */
  77 int update_path_in_gitmodules(const char *oldpath, const char *newpath)
  78 {
  79         struct strbuf entry = STRBUF_INIT;
  80         const struct submodule *submodule;
  81
  82         if (!file_exists(GITMODULES_FILE)) /* Do nothing without .gitmodules */
  83                 return -1;
  84
  85         if (is_gitmodules_unmerged(&the_index))
  86                 die(_("Cannot change unmerged .gitmodules, resolve merge conflicts first"));
  87
  88         submodule = submodule_from_path(&null_oid, oldpath);
  89         if (!submodule || !submodule->name) {
  90                 warning(_("Could not find section in .gitmodules where path=%s"), oldpath);
  91                 return -1;
  92         }
  93         strbuf_addstr(&entry, "submodule.");
  94         strbuf_addstr(&entry, submodule->name);
  95         strbuf_addstr(&entry, ".path");
  96         if (git_config_set_in_file_gently(GITMODULES_FILE, entry.buf, newpath) < 0) {
  97                 /* Maybe the user already did that, don't error out here */
  98                 warning(_("Could not update .gitmodules entry %s"), entry.buf);
  99                 strbuf_release(&entry);
 100                 return -1;
 101         }
 102         strbuf_release(&entry);
 103         return 0;
 104 }
 105
 106 /*
 107  * Try to remove the "submodule.<name>" section from .gitmodules where the given
 108  * path is configured. Return 0 only if a .gitmodules file was found, a section
 109  * with the correct path=<path> setting was found and we could remove it.
 110  */
 111 int remove_path_from_gitmodules(const char *path)
 112 {
 113         struct strbuf sect = STRBUF_INIT;
 114         const struct submodule *submodule;
 115
 116         if (!file_exists(GITMODULES_FILE)) /* Do nothing without .gitmodules */
 117                 return -1;
 118
 119         if (is_gitmodules_unmerged(&the_index))
 120                 die(_("Cannot change unmerged .gitmodules, resolve merge conflicts first"));
 121
 122         submodule = submodule_from_path(&null_oid, path);
 123         if (!submodule || !submodule->name) {
 124                 warning(_("Could not find section in .gitmodules where path=%s"), path);
 125                 return -1;
 126         }
 127         strbuf_addstr(&sect, "submodule.");
 128         strbuf_addstr(&sect, submodule->name);
 129         if (git_config_rename_section_in_file(GITMODULES_FILE, sect.buf, NULL) < 0) {
 130                 /* Maybe the user already did that, don't error out here */
 131                 warning(_("Could not remove .gitmodules entry for %s"), path);
 132                 strbuf_release(&sect);
 133                 return -1;
 134         }
 135         strbuf_release(&sect);
 136         return 0;
 137 }
 138
 139 void stage_updated_gitmodules(void)
 140 {
 141         if (add_file_to_cache(GITMODULES_FILE, 0))
 142                 die(_("staging updated .gitmodules failed"));
 143 }
 144
 145 static int add_submodule_odb(const char *path)
 146 {
 147         struct strbuf objects_directory = STRBUF_INIT;
 148         int ret = 0;
 149
 150         ret = strbuf_git_path_submodule(&objects_directory, path, "objects/");
 151         if (ret)
 152                 goto done;
 153         if (!is_directory(objects_directory.buf)) {
 154                 ret = -1;
 155                 goto done;
 156         }
 157         add_to_alternates_memory(objects_directory.buf);
 158 done:
 159         strbuf_release(&objects_directory);
 160         return ret;
 161 }
 162
 163 void set_diffopt_flags_from_submodule_config(struct diff_options *diffopt,
 164                                              const char *path)
 165 {
 166         const struct submodule *submodule = submodule_from_path(&null_oid, path);
 167         if (submodule) {
 168                 const char *ignore;
 169                 char *key;
 170
 171                 key = xstrfmt("submodule.%s.ignore", submodule->name);
 172                 if (repo_config_get_string_const(the_repository, key, &ignore))
 173                         ignore = submodule->ignore;
 174                 free(key);
 175
 176                 if (ignore)
 177                         handle_ignore_submodules_arg(diffopt, ignore);
 178                 else if (is_gitmodules_unmerged(&the_index))
 179                         DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
 180         }
 181 }
 182
 183 /* Cheap function that only determines if we're interested in submodules at all */
 184 int git_default_submodule_config(const char *var, const char *value, void *cb)
 185 {
 186         if (!strcmp(var, "submodule.recurse")) {
 187                 int v = git_config_bool(var, value) ?
 188                         RECURSE_SUBMODULES_ON : RECURSE_SUBMODULES_OFF;
 189                 config_update_recurse_submodules = v;
 190         }
 191         return 0;
 192 }
 193
 194 int option_parse_recurse_submodules_worktree_updater(const struct option *opt,
 195                                                      const char *arg, int unset)
 196 {
 197         if (unset) {
 198                 config_update_recurse_submodules = RECURSE_SUBMODULES_OFF;
 199                 return 0;
 200         }
 201         if (arg)
 202                 config_update_recurse_submodules =
 203                         parse_update_recurse_submodules_arg(opt->long_name,
 204                                                             arg);
 205         else
 206                 config_update_recurse_submodules = RECURSE_SUBMODULES_ON;
 207
 208         return 0;
 209 }
 210
 211 /*
 212  * Determine if a submodule has been initialized at a given 'path'
 213  */
 214 int is_submodule_active(struct repository *repo, const char *path)
 215 {
 216         int ret = 0;
 217         char *key = NULL;
 218         char *value = NULL;
 219         const struct string_list *sl;
 220         const struct submodule *module;
 221
 222         module = submodule_from_cache(repo, &null_oid, path);
 223
 224         /* early return if there isn't a path->module mapping */
 225         if (!module)
 226                 return 0;
 227
 228         /* submodule.<name>.active is set */
 229         key = xstrfmt("submodule.%s.active", module->name);
 230         if (!repo_config_get_bool(repo, key, &ret)) {
 231                 free(key);
 232                 return ret;
 233         }
 234         free(key);
 235
 236         /* submodule.active is set */
 237         sl = repo_config_get_value_multi(repo, "submodule.active");
 238         if (sl) {
 239                 struct pathspec ps;
 240                 struct argv_array args = ARGV_ARRAY_INIT;
 241                 const struct string_list_item *item;
 242
 243                 for_each_string_list_item(item, sl) {
 244                         argv_array_push(&args, item->string);
 245                 }
 246
 247                 parse_pathspec(&ps, 0, 0, NULL, args.argv);
 248                 ret = match_pathspec(&ps, path, strlen(path), 0, NULL, 1);
 249
 250                 argv_array_clear(&args);
 251                 clear_pathspec(&ps);
 252                 return ret;
 253         }
 254
 255         /* fallback to checking if the URL is set */
 256         key = xstrfmt("submodule.%s.url", module->name);
 257         ret = !repo_config_get_string(repo, key, &value);
 258
 259         free(value);
 260         free(key);
 261         return ret;
 262 }
 263
 264 int is_submodule_populated_gently(const char *path, int *return_error_code)
 265 {
 266         int ret = 0;
 267         char *gitdir = xstrfmt("%s/.git", path);
 268
 269         if (resolve_gitdir_gently(gitdir, return_error_code))
 270                 ret = 1;
 271
 272         free(gitdir);
 273         return ret;
 274 }
 275
 276 /*
 277  * Dies if the provided 'prefix' corresponds to an unpopulated submodule
 278  */
 279 void die_in_unpopulated_submodule(const struct index_state *istate,
 280                                   const char *prefix)
 281 {
 282         int i, prefixlen;
 283
 284         if (!prefix)
 285                 return;
 286
 287         prefixlen = strlen(prefix);
 288
 289         for (i = 0; i < istate->cache_nr; i++) {
 290                 struct cache_entry *ce = istate->cache[i];
 291                 int ce_len = ce_namelen(ce);
 292
 293                 if (!S_ISGITLINK(ce->ce_mode))
 294                         continue;
 295                 if (prefixlen <= ce_len)
 296                         continue;
 297                 if (strncmp(ce->name, prefix, ce_len))
 298                         continue;
 299                 if (prefix[ce_len] != '/')
 300                         continue;
 301
 302                 die(_("in unpopulated submodule '%s'"), ce->name);
 303         }
 304 }
 305
 306 /*
 307  * Dies if any paths in the provided pathspec descends into a submodule
 308  */
 309 void die_path_inside_submodule(const struct index_state *istate,
 310                                const struct pathspec *ps)
 311 {
 312         int i, j;
 313
 314         for (i = 0; i < istate->cache_nr; i++) {
 315                 struct cache_entry *ce = istate->cache[i];
 316                 int ce_len = ce_namelen(ce);
 317
 318                 if (!S_ISGITLINK(ce->ce_mode))
 319                         continue;
 320
 321                 for (j = 0; j < ps->nr ; j++) {
 322                         const struct pathspec_item *item = &ps->items[j];
 323
 324                         if (item->len <= ce_len)
 325                                 continue;
 326                         if (item->match[ce_len] != '/')
 327                                 continue;
 328                         if (strncmp(ce->name, item->match, ce_len))
 329                                 continue;
 330                         if (item->len == ce_len + 1)
 331                                 continue;
 332
 333                         die(_("Pathspec '%s' is in submodule '%.*s'"),
 334                             item->original, ce_len, ce->name);
 335                 }
 336         }
 337 }
 338
 339 enum submodule_update_type parse_submodule_update_type(const char *value)
 340 {
 341         if (!strcmp(value, "none"))
 342                 return SM_UPDATE_NONE;
 343         else if (!strcmp(value, "checkout"))
 344                 return SM_UPDATE_CHECKOUT;
 345         else if (!strcmp(value, "rebase"))
 346                 return SM_UPDATE_REBASE;
 347         else if (!strcmp(value, "merge"))
 348                 return SM_UPDATE_MERGE;
 349         else if (*value == '!')
 350                 return SM_UPDATE_COMMAND;
 351         else
 352                 return SM_UPDATE_UNSPECIFIED;
 353 }
 354
 355 int parse_submodule_update_strategy(const char *value,
 356                 struct submodule_update_strategy *dst)
 357 {
 358         enum submodule_update_type type;
 359
 360         free((void*)dst->command);
 361         dst->command = NULL;
 362
 363         type = parse_submodule_update_type(value);
 364         if (type == SM_UPDATE_UNSPECIFIED)
 365                 return -1;
 366
 367         dst->type = type;
 368         if (type == SM_UPDATE_COMMAND)
 369                 dst->command = xstrdup(value + 1);
 370
 371         return 0;
 372 }
 373
 374 const char *submodule_strategy_to_string(const struct submodule_update_strategy *s)
 375 {
 376         struct strbuf sb = STRBUF_INIT;
 377         switch (s->type) {
 378         case SM_UPDATE_CHECKOUT:
 379                 return "checkout";
 380         case SM_UPDATE_MERGE:
 381                 return "merge";
 382         case SM_UPDATE_REBASE:
 383                 return "rebase";
 384         case SM_UPDATE_NONE:
 385                 return "none";
 386         case SM_UPDATE_UNSPECIFIED:
 387                 return NULL;
 388         case SM_UPDATE_COMMAND:
 389                 strbuf_addf(&sb, "!%s", s->command);
 390                 return strbuf_detach(&sb, NULL);
 391         }
 392         return NULL;
 393 }
 394
 395 void handle_ignore_submodules_arg(struct diff_options *diffopt,
 396                                   const char *arg)
 397 {
 398         DIFF_OPT_CLR(diffopt, IGNORE_SUBMODULES);
 399         DIFF_OPT_CLR(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 400         DIFF_OPT_CLR(diffopt, IGNORE_DIRTY_SUBMODULES);
 401
 402         if (!strcmp(arg, "all"))
 403                 DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
 404         else if (!strcmp(arg, "untracked"))
 405                 DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 406         else if (!strcmp(arg, "dirty"))
 407                 DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES);
 408         else if (strcmp(arg, "none"))
 409                 die("bad --ignore-submodules argument: %s", arg);
 410 }
 411
 412 static int prepare_submodule_summary(struct rev_info *rev, const char *path,
 413                 struct commit *left, struct commit *right,
 414                 struct commit_list *merge_bases)
 415 {
 416         struct commit_list *list;
 417
 418         init_revisions(rev, NULL);
 419         setup_revisions(0, NULL, rev, NULL);
 420         rev->left_right = 1;
 421         rev->first_parent_only = 1;
 422         left->object.flags |= SYMMETRIC_LEFT;
 423         add_pending_object(rev, &left->object, path);
 424         add_pending_object(rev, &right->object, path);
 425         for (list = merge_bases; list; list = list->next) {
 426                 list->item->object.flags |= UNINTERESTING;
 427                 add_pending_object(rev, &list->item->object,
 428                         oid_to_hex(&list->item->object.oid));
 429         }
 430         return prepare_revision_walk(rev);
 431 }
 432
 433 static void print_submodule_summary(struct rev_info *rev, struct diff_options *o)
 434 {
 435         static const char format[] = "  %m %s";
 436         struct strbuf sb = STRBUF_INIT;
 437         struct commit *commit;
 438
 439         while ((commit = get_revision(rev))) {
 440                 struct pretty_print_context ctx = {0};
 441                 ctx.date_mode = rev->date_mode;
 442                 ctx.output_encoding = get_log_output_encoding();
 443                 strbuf_setlen(&sb, 0);
 444                 format_commit_message(commit, format, &sb, &ctx);
 445                 strbuf_addch(&sb, '\n');
 446                 if (commit->object.flags & SYMMETRIC_LEFT)
 447                         diff_emit_submodule_del(o, sb.buf);
 448                 else
 449                         diff_emit_submodule_add(o, sb.buf);
 450         }
 451         strbuf_release(&sb);
 452 }
 453
 454 static void prepare_submodule_repo_env_no_git_dir(struct argv_array *out)
 455 {
 456         const char * const *var;
 457
 458         for (var = local_repo_env; *var; var++) {
 459                 if (strcmp(*var, CONFIG_DATA_ENVIRONMENT))
 460                         argv_array_push(out, *var);
 461         }
 462 }
 463
 464 void prepare_submodule_repo_env(struct argv_array *out)
 465 {
 466         prepare_submodule_repo_env_no_git_dir(out);
 467         argv_array_pushf(out, "%s=%s", GIT_DIR_ENVIRONMENT,
 468                          DEFAULT_GIT_DIR_ENVIRONMENT);
 469 }
 470
 471 /* Helper function to display the submodule header line prior to the full
 472  * summary output. If it can locate the submodule objects directory it will
 473  * attempt to lookup both the left and right commits and put them into the
 474  * left and right pointers.
 475  */
 476 static void show_submodule_header(struct diff_options *o, const char *path,
 477                 struct object_id *one, struct object_id *two,
 478                 unsigned dirty_submodule,
 479                 struct commit **left, struct commit **right,
 480                 struct commit_list **merge_bases)
 481 {
 482         const char *message = NULL;
 483         struct strbuf sb = STRBUF_INIT;
 484         int fast_forward = 0, fast_backward = 0;
 485
 486         if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
 487                 diff_emit_submodule_untracked(o, path);
 488
 489         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
 490                 diff_emit_submodule_modified(o, path);
 491
 492         if (is_null_oid(one))
 493                 message = "(new submodule)";
 494         else if (is_null_oid(two))
 495                 message = "(submodule deleted)";
 496
 497         if (add_submodule_odb(path)) {
 498                 if (!message)
 499                         message = "(not initialized)";
 500                 goto output_header;
 501         }
 502
 503         /*
 504          * Attempt to lookup the commit references, and determine if this is
 505          * a fast forward or fast backwards update.
 506          */
 507         *left = lookup_commit_reference(one);
 508         *right = lookup_commit_reference(two);
 509
 510         /*
 511          * Warn about missing commits in the submodule project, but only if
 512          * they aren't null.
 513          */
 514         if ((!is_null_oid(one) && !*left) ||
 515              (!is_null_oid(two) && !*right))
 516                 message = "(commits not present)";
 517
 518         *merge_bases = get_merge_bases(*left, *right);
 519         if (*merge_bases) {
 520                 if ((*merge_bases)->item == *left)
 521                         fast_forward = 1;
 522                 else if ((*merge_bases)->item == *right)
 523                         fast_backward = 1;
 524         }
 525
 526         if (!oidcmp(one, two)) {
 527                 strbuf_release(&sb);
 528                 return;
 529         }
 530
 531 output_header:
 532         strbuf_addf(&sb, "Submodule %s ", path);
 533         strbuf_add_unique_abbrev(&sb, one->hash, DEFAULT_ABBREV);
 534         strbuf_addstr(&sb, (fast_backward || fast_forward) ? ".." : "...");
 535         strbuf_add_unique_abbrev(&sb, two->hash, DEFAULT_ABBREV);
 536         if (message)
 537                 strbuf_addf(&sb, " %s\n", message);
 538         else
 539                 strbuf_addf(&sb, "%s:\n", fast_backward ? " (rewind)" : "");
 540         diff_emit_submodule_header(o, sb.buf);
 541
 542         strbuf_release(&sb);
 543 }
 544
 545 void show_submodule_summary(struct diff_options *o, const char *path,
 546                 struct object_id *one, struct object_id *two,
 547                 unsigned dirty_submodule)
 548 {
 549         struct rev_info rev;
 550         struct commit *left = NULL, *right = NULL;
 551         struct commit_list *merge_bases = NULL;
 552
 553         show_submodule_header(o, path, one, two, dirty_submodule,
 554                               &left, &right, &merge_bases);
 555
 556         /*
 557          * If we don't have both a left and a right pointer, there is no
 558          * reason to try and display a summary. The header line should contain
 559          * all the information the user needs.
 560          */
 561         if (!left || !right)
 562                 goto out;
 563
 564         /* Treat revision walker failure the same as missing commits */
 565         if (prepare_submodule_summary(&rev, path, left, right, merge_bases)) {
 566                 diff_emit_submodule_error(o, "(revision walker failed)\n");
 567                 goto out;
 568         }
 569
 570         print_submodule_summary(&rev, o);
 571
 572 out:
 573         if (merge_bases)
 574                 free_commit_list(merge_bases);
 575         clear_commit_marks(left, ~0);
 576         clear_commit_marks(right, ~0);
 577 }
 578
 579 void show_submodule_inline_diff(struct diff_options *o, const char *path,
 580                 struct object_id *one, struct object_id *two,
 581                 unsigned dirty_submodule)
 582 {
 583         const struct object_id *old = &empty_tree_oid, *new = &empty_tree_oid;
 584         struct commit *left = NULL, *right = NULL;
 585         struct commit_list *merge_bases = NULL;
 586         struct child_process cp = CHILD_PROCESS_INIT;
 587         struct strbuf sb = STRBUF_INIT;
 588
 589         show_submodule_header(o, path, one, two, dirty_submodule,
 590                               &left, &right, &merge_bases);
 591
 592         /* We need a valid left and right commit to display a difference */
 593         if (!(left || is_null_oid(one)) ||
 594             !(right || is_null_oid(two)))
 595                 goto done;
 596
 597         if (left)
 598                 old = one;
 599         if (right)
 600                 new = two;
 601
 602         cp.git_cmd = 1;
 603         cp.dir = path;
 604         cp.out = -1;
 605         cp.no_stdin = 1;
 606
 607         /* TODO: other options may need to be passed here. */
 608         argv_array_pushl(&cp.args, "diff", "--submodule=diff", NULL);
 609         argv_array_pushf(&cp.args, "--color=%s", want_color(o->use_color) ?
 610                          "always" : "never");
 611
 612         if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
 613                 argv_array_pushf(&cp.args, "--src-prefix=%s%s/",
 614                                  o->b_prefix, path);
 615                 argv_array_pushf(&cp.args, "--dst-prefix=%s%s/",
 616                                  o->a_prefix, path);
 617         } else {
 618                 argv_array_pushf(&cp.args, "--src-prefix=%s%s/",
 619                                  o->a_prefix, path);
 620                 argv_array_pushf(&cp.args, "--dst-prefix=%s%s/",
 621                                  o->b_prefix, path);
 622         }
 623         argv_array_push(&cp.args, oid_to_hex(old));
 624         /*
 625          * If the submodule has modified content, we will diff against the
 626          * work tree, under the assumption that the user has asked for the
 627          * diff format and wishes to actually see all differences even if they
 628          * haven't yet been committed to the submodule yet.
 629          */
 630         if (!(dirty_submodule & DIRTY_SUBMODULE_MODIFIED))
 631                 argv_array_push(&cp.args, oid_to_hex(new));
 632
 633         prepare_submodule_repo_env(&cp.env_array);
 634         if (start_command(&cp))
 635                 diff_emit_submodule_error(o, "(diff failed)\n");
 636
 637         while (strbuf_getwholeline_fd(&sb, cp.out, '\n') != EOF)
 638                 diff_emit_submodule_pipethrough(o, sb.buf, sb.len);
 639
 640         if (finish_command(&cp))
 641                 diff_emit_submodule_error(o, "(diff failed)\n");
 642
 643 done:
 644         strbuf_release(&sb);
 645         if (merge_bases)
 646                 free_commit_list(merge_bases);
 647         if (left)
 648                 clear_commit_marks(left, ~0);
 649         if (right)
 650                 clear_commit_marks(right, ~0);
 651 }
 652
 653 int should_update_submodules(void)
 654 {
 655         return config_update_recurse_submodules == RECURSE_SUBMODULES_ON;
 656 }
 657
 658 const struct submodule *submodule_from_ce(const struct cache_entry *ce)
 659 {
 660         if (!S_ISGITLINK(ce->ce_mode))
 661                 return NULL;
 662
 663         if (!should_update_submodules())
 664                 return NULL;
 665
 666         return submodule_from_path(&null_oid, ce->name);
 667 }
 668
 669 static struct oid_array *submodule_commits(struct string_list *submodules,
 670                                            const char *path)
 671 {
 672         struct string_list_item *item;
 673
 674         item = string_list_insert(submodules, path);
 675         if (item->util)
 676                 return (struct oid_array *) item->util;
 677
 678         /* NEEDSWORK: should we have oid_array_init()? */
 679         item->util = xcalloc(1, sizeof(struct oid_array));
 680         return (struct oid_array *) item->util;
 681 }
 682
 683 static void collect_changed_submodules_cb(struct diff_queue_struct *q,
 684                                           struct diff_options *options,
 685                                           void *data)
 686 {
 687         int i;
 688         struct string_list *changed = data;
 689
 690         for (i = 0; i < q->nr; i++) {
 691                 struct diff_filepair *p = q->queue[i];
 692                 struct oid_array *commits;
 693                 if (!S_ISGITLINK(p->two->mode))
 694                         continue;
 695
 696                 if (S_ISGITLINK(p->one->mode)) {
 697                         /*
 698                          * NEEDSWORK: We should honor the name configured in
 699                          * the .gitmodules file of the commit we are examining
 700                          * here to be able to correctly follow submodules
 701                          * being moved around.
 702                          */
 703                         commits = submodule_commits(changed, p->two->path);
 704                         oid_array_append(commits, &p->two->oid);
 705                 } else {
 706                         /* Submodule is new or was moved here */
 707                         /*
 708                          * NEEDSWORK: When the .git directories of submodules
 709                          * live inside the superprojects .git directory some
 710                          * day we should fetch new submodules directly into
 711                          * that location too when config or options request
 712                          * that so they can be checked out from there.
 713                          */
 714                         continue;
 715                 }
 716         }
 717 }
 718
 719 /*
 720  * Collect the paths of submodules in 'changed' which have changed based on
 721  * the revisions as specified in 'argv'.  Each entry in 'changed' will also
 722  * have a corresponding 'struct oid_array' (in the 'util' field) which lists
 723  * what the submodule pointers were updated to during the change.
 724  */
 725 static void collect_changed_submodules(struct string_list *changed,
 726                                        struct argv_array *argv)
 727 {
 728         struct rev_info rev;
 729         const struct commit *commit;
 730
 731         init_revisions(&rev, NULL);
 732         setup_revisions(argv->argc, argv->argv, &rev, NULL);
 733         if (prepare_revision_walk(&rev))
 734                 die("revision walk setup failed");
 735
 736         while ((commit = get_revision(&rev))) {
 737                 struct rev_info diff_rev;
 738
 739                 init_revisions(&diff_rev, NULL);
 740                 diff_rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
 741                 diff_rev.diffopt.format_callback = collect_changed_submodules_cb;
 742                 diff_rev.diffopt.format_callback_data = changed;
 743                 diff_tree_combined_merge(commit, 1, &diff_rev);
 744         }
 745
 746         reset_revision_walk();
 747 }
 748
 749 static void free_submodules_oids(struct string_list *submodules)
 750 {
 751         struct string_list_item *item;
 752         for_each_string_list_item(item, submodules)
 753                 oid_array_clear((struct oid_array *) item->util);
 754         string_list_clear(submodules, 1);
 755 }
 756
 757 static int has_remote(const char *refname, const struct object_id *oid,
 758                       int flags, void *cb_data)
 759 {
 760         return 1;
 761 }
 762
 763 static int append_oid_to_argv(const struct object_id *oid, void *data)
 764 {
 765         struct argv_array *argv = data;
 766         argv_array_push(argv, oid_to_hex(oid));
 767         return 0;
 768 }
 769
 770 struct has_commit_data {
 771         int result;
 772         const char *path;
 773 };
 774
 775 static int check_has_commit(const struct object_id *oid, void *data)
 776 {
 777         struct has_commit_data *cb = data;
 778
 779         enum object_type type = sha1_object_info(oid->hash, NULL);
 780
 781         switch (type) {
 782         case OBJ_COMMIT:
 783                 return 0;
 784         case OBJ_BAD:
 785                 /*
 786                  * Object is missing or invalid. If invalid, an error message
 787                  * has already been printed.
 788                  */
 789                 cb->result = 0;
 790                 return 0;
 791         default:
 792                 die(_("submodule entry '%s' (%s) is a %s, not a commit"),
 793                     cb->path, oid_to_hex(oid), typename(type));
 794         }
 795 }
 796
 797 static int submodule_has_commits(const char *path, struct oid_array *commits)
 798 {
 799         struct has_commit_data has_commit = { 1, path };
 800
 801         /*
 802          * Perform a cheap, but incorrect check for the existence of 'commits'.
 803          * This is done by adding the submodule's object store to the in-core
 804          * object store, and then querying for each commit's existence.  If we
 805          * do not have the commit object anywhere, there is no chance we have
 806          * it in the object store of the correct submodule and have it
 807          * reachable from a ref, so we can fail early without spawning rev-list
 808          * which is expensive.
 809          */
 810         if (add_submodule_odb(path))
 811                 return 0;
 812
 813         oid_array_for_each_unique(commits, check_has_commit, &has_commit);
 814
 815         if (has_commit.result) {
 816                 /*
 817                  * Even if the submodule is checked out and the commit is
 818                  * present, make sure it exists in the submodule's object store
 819                  * and that it is reachable from a ref.
 820                  */
 821                 struct child_process cp = CHILD_PROCESS_INIT;
 822                 struct strbuf out = STRBUF_INIT;
 823
 824                 argv_array_pushl(&cp.args, "rev-list", "-n", "1", NULL);
 825                 oid_array_for_each_unique(commits, append_oid_to_argv, &cp.args);
 826                 argv_array_pushl(&cp.args, "--not", "--all", NULL);
 827
 828                 prepare_submodule_repo_env(&cp.env_array);
 829                 cp.git_cmd = 1;
 830                 cp.no_stdin = 1;
 831                 cp.dir = path;
 832
 833                 if (capture_command(&cp, &out, GIT_MAX_HEXSZ + 1) || out.len)
 834                         has_commit.result = 0;
 835
 836                 strbuf_release(&out);
 837         }
 838
 839         return has_commit.result;
 840 }
 841
 842 static int submodule_needs_pushing(const char *path, struct oid_array *commits)
 843 {
 844         if (!submodule_has_commits(path, commits))
 845                 /*
 846                  * NOTE: We do consider it safe to return "no" here. The
 847                  * correct answer would be "We do not know" instead of
 848                  * "No push needed", but it is quite hard to change
 849                  * the submodule pointer without having the submodule
 850                  * around. If a user did however change the submodules
 851                  * without having the submodule around, this indicates
 852                  * an expert who knows what they are doing or a
 853                  * maintainer integrating work from other people. In
 854                  * both cases it should be safe to skip this check.
 855                  */
 856                 return 0;
 857
 858         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 859                 struct child_process cp = CHILD_PROCESS_INIT;
 860                 struct strbuf buf = STRBUF_INIT;
 861                 int needs_pushing = 0;
 862
 863                 argv_array_push(&cp.args, "rev-list");
 864                 oid_array_for_each_unique(commits, append_oid_to_argv, &cp.args);
 865                 argv_array_pushl(&cp.args, "--not", "--remotes", "-n", "1" , NULL);
 866
 867                 prepare_submodule_repo_env(&cp.env_array);
 868                 cp.git_cmd = 1;
 869                 cp.no_stdin = 1;
 870                 cp.out = -1;
 871                 cp.dir = path;
 872                 if (start_command(&cp))
 873                         die("Could not run 'git rev-list <commits> --not --remotes -n 1' command in submodule %s",
 874                                         path);
 875                 if (strbuf_read(&buf, cp.out, 41))
 876                         needs_pushing = 1;
 877                 finish_command(&cp);
 878                 close(cp.out);
 879                 strbuf_release(&buf);
 880                 return needs_pushing;
 881         }
 882
 883         return 0;
 884 }
 885
 886 int find_unpushed_submodules(struct oid_array *commits,
 887                 const char *remotes_name, struct string_list *needs_pushing)
 888 {
 889         struct string_list submodules = STRING_LIST_INIT_DUP;
 890         struct string_list_item *submodule;
 891         struct argv_array argv = ARGV_ARRAY_INIT;
 892
 893         /* argv.argv[0] will be ignored by setup_revisions */
 894         argv_array_push(&argv, "find_unpushed_submodules");
 895         oid_array_for_each_unique(commits, append_oid_to_argv, &argv);
 896         argv_array_push(&argv, "--not");
 897         argv_array_pushf(&argv, "--remotes=%s", remotes_name);
 898
 899         collect_changed_submodules(&submodules, &argv);
 900
 901         for_each_string_list_item(submodule, &submodules) {
 902                 struct oid_array *commits = submodule->util;
 903                 const char *path = submodule->string;
 904
 905                 if (submodule_needs_pushing(path, commits))
 906                         string_list_insert(needs_pushing, path);
 907         }
 908
 909         free_submodules_oids(&submodules);
 910         argv_array_clear(&argv);
 911
 912         return needs_pushing->nr;
 913 }
 914
 915 static int push_submodule(const char *path,
 916                           const struct remote *remote,
 917                           const char **refspec, int refspec_nr,
 918                           const struct string_list *push_options,
 919                           int dry_run)
 920 {
 921         if (add_submodule_odb(path))
 922                 return 1;
 923
 924         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 925                 struct child_process cp = CHILD_PROCESS_INIT;
 926                 argv_array_push(&cp.args, "push");
 927                 if (dry_run)
 928                         argv_array_push(&cp.args, "--dry-run");
 929
 930                 if (push_options && push_options->nr) {
 931                         const struct string_list_item *item;
 932                         for_each_string_list_item(item, push_options)
 933                                 argv_array_pushf(&cp.args, "--push-option=%s",
 934                                                  item->string);
 935                 }
 936
 937                 if (remote->origin != REMOTE_UNCONFIGURED) {
 938                         int i;
 939                         argv_array_push(&cp.args, remote->name);
 940                         for (i = 0; i < refspec_nr; i++)
 941                                 argv_array_push(&cp.args, refspec[i]);
 942                 }
 943
 944                 prepare_submodule_repo_env(&cp.env_array);
 945                 cp.git_cmd = 1;
 946                 cp.no_stdin = 1;
 947                 cp.dir = path;
 948                 if (run_command(&cp))
 949                         return 0;
 950                 close(cp.out);
 951         }
 952
 953         return 1;
 954 }
 955
 956 /*
 957  * Perform a check in the submodule to see if the remote and refspec work.
 958  * Die if the submodule can't be pushed.
 959  */
 960 static void submodule_push_check(const char *path, const char *head,
 961                                  const struct remote *remote,
 962                                  const char **refspec, int refspec_nr)
 963 {
 964         struct child_process cp = CHILD_PROCESS_INIT;
 965         int i;
 966
 967         argv_array_push(&cp.args, "submodule--helper");
 968         argv_array_push(&cp.args, "push-check");
 969         argv_array_push(&cp.args, head);
 970         argv_array_push(&cp.args, remote->name);
 971
 972         for (i = 0; i < refspec_nr; i++)
 973                 argv_array_push(&cp.args, refspec[i]);
 974
 975         prepare_submodule_repo_env(&cp.env_array);
 976         cp.git_cmd = 1;
 977         cp.no_stdin = 1;
 978         cp.no_stdout = 1;
 979         cp.dir = path;
 980
 981         /*
 982          * Simply indicate if 'submodule--helper push-check' failed.
 983          * More detailed error information will be provided by the
 984          * child process.
 985          */
 986         if (run_command(&cp))
 987                 die("process for submodule '%s' failed", path);
 988 }
 989
 990 int push_unpushed_submodules(struct oid_array *commits,
 991                              const struct remote *remote,
 992                              const char **refspec, int refspec_nr,
 993                              const struct string_list *push_options,
 994                              int dry_run)
 995 {
 996         int i, ret = 1;
 997         struct string_list needs_pushing = STRING_LIST_INIT_DUP;
 998
 999         if (!find_unpushed_submodules(commits, remote->name, &needs_pushing))
1000                 return 1;
1001
1002         /*
1003          * Verify that the remote and refspec can be propagated to all
1004          * submodules.  This check can be skipped if the remote and refspec
1005          * won't be propagated due to the remote being unconfigured (e.g. a URL
1006          * instead of a remote name).
1007          */
1008         if (remote->origin != REMOTE_UNCONFIGURED) {
1009                 char *head;
1010                 struct object_id head_oid;
1011
1012                 head = resolve_refdup("HEAD", 0, head_oid.hash, NULL);
1013                 if (!head)
1014                         die(_("Failed to resolve HEAD as a valid ref."));
1015
1016                 for (i = 0; i < needs_pushing.nr; i++)
1017                         submodule_push_check(needs_pushing.items[i].string,
1018                                              head, remote,
1019                                              refspec, refspec_nr);
1020                 free(head);
1021         }
1022
1023         /* Actually push the submodules */
1024         for (i = 0; i < needs_pushing.nr; i++) {
1025                 const char *path = needs_pushing.items[i].string;
1026                 fprintf(stderr, "Pushing submodule '%s'\n", path);
1027                 if (!push_submodule(path, remote, refspec, refspec_nr,
1028                                     push_options, dry_run)) {
1029                         fprintf(stderr, "Unable to push submodule '%s'\n", path);
1030                         ret = 0;
1031                 }
1032         }
1033
1034         string_list_clear(&needs_pushing, 0);
1035
1036         return ret;
1037 }
1038
1039 static int append_oid_to_array(const char *ref, const struct object_id *oid,
1040                                int flags, void *data)
1041 {
1042         struct oid_array *array = data;
1043         oid_array_append(array, oid);
1044         return 0;
1045 }
1046
1047 void check_for_new_submodule_commits(struct object_id *oid)
1048 {
1049         if (!initialized_fetch_ref_tips) {
1050                 for_each_ref(append_oid_to_array, &ref_tips_before_fetch);
1051                 initialized_fetch_ref_tips = 1;
1052         }
1053
1054         oid_array_append(&ref_tips_after_fetch, oid);
1055 }
1056
1057 static void calculate_changed_submodule_paths(void)
1058 {
1059         struct argv_array argv = ARGV_ARRAY_INIT;
1060         struct string_list changed_submodules = STRING_LIST_INIT_DUP;
1061         const struct string_list_item *item;
1062
1063         /* No need to check if there are no submodules configured */
1064         if (!submodule_from_path(NULL, NULL))
1065                 return;
1066
1067         argv_array_push(&argv, "--"); /* argv[0] program name */
1068         oid_array_for_each_unique(&ref_tips_after_fetch,
1069                                    append_oid_to_argv, &argv);
1070         argv_array_push(&argv, "--not");
1071         oid_array_for_each_unique(&ref_tips_before_fetch,
1072                                    append_oid_to_argv, &argv);
1073
1074         /*
1075          * Collect all submodules (whether checked out or not) for which new
1076          * commits have been recorded upstream in "changed_submodule_paths".
1077          */
1078         collect_changed_submodules(&changed_submodules, &argv);
1079
1080         for_each_string_list_item(item, &changed_submodules) {
1081                 struct oid_array *commits = item->util;
1082                 const char *path = item->string;
1083
1084                 if (!submodule_has_commits(path, commits))
1085                         string_list_append(&changed_submodule_paths, path);
1086         }
1087
1088         free_submodules_oids(&changed_submodules);
1089         argv_array_clear(&argv);
1090         oid_array_clear(&ref_tips_before_fetch);
1091         oid_array_clear(&ref_tips_after_fetch);
1092         initialized_fetch_ref_tips = 0;
1093 }
1094
1095 int submodule_touches_in_range(struct object_id *excl_oid,
1096                                struct object_id *incl_oid)
1097 {
1098         struct string_list subs = STRING_LIST_INIT_DUP;
1099         struct argv_array args = ARGV_ARRAY_INIT;
1100         int ret;
1101
1102         /* No need to check if there are no submodules configured */
1103         if (!submodule_from_path(NULL, NULL))
1104                 return 0;
1105
1106         argv_array_push(&args, "--"); /* args[0] program name */
1107         argv_array_push(&args, oid_to_hex(incl_oid));
1108         argv_array_push(&args, "--not");
1109         argv_array_push(&args, oid_to_hex(excl_oid));
1110
1111         collect_changed_submodules(&subs, &args);
1112         ret = subs.nr;
1113
1114         argv_array_clear(&args);
1115
1116         free_submodules_oids(&subs);
1117         return ret;
1118 }
1119
1120 struct submodule_parallel_fetch {
1121         int count;
1122         struct argv_array args;
1123         const char *work_tree;
1124         const char *prefix;
1125         int command_line_option;
1126         int default_option;
1127         int quiet;
1128         int result;
1129 };
1130 #define SPF_INIT {0, ARGV_ARRAY_INIT, NULL, NULL, 0, 0, 0, 0}
1131
1132 static int get_next_submodule(struct child_process *cp,
1133                               struct strbuf *err, void *data, void **task_cb)
1134 {
1135         int ret = 0;
1136         struct submodule_parallel_fetch *spf = data;
1137
1138         for (; spf->count < active_nr; spf->count++) {
1139                 struct strbuf submodule_path = STRBUF_INIT;
1140                 struct strbuf submodule_git_dir = STRBUF_INIT;
1141                 struct strbuf submodule_prefix = STRBUF_INIT;
1142                 const struct cache_entry *ce = active_cache[spf->count];
1143                 const char *git_dir, *default_argv;
1144                 const struct submodule *submodule;
1145
1146                 if (!S_ISGITLINK(ce->ce_mode))
1147                         continue;
1148
1149                 submodule = submodule_from_path(&null_oid, ce->name);
1150
1151                 default_argv = "yes";
1152                 if (spf->command_line_option == RECURSE_SUBMODULES_DEFAULT) {
1153                         int fetch_recurse = RECURSE_SUBMODULES_NONE;
1154
1155                         if (submodule) {
1156                                 char *key;
1157                                 const char *value;
1158
1159                                 fetch_recurse = submodule->fetch_recurse;
1160                                 key = xstrfmt("submodule.%s.fetchRecurseSubmodules", submodule->name);
1161                                 if (!repo_config_get_string_const(the_repository, key, &value)) {
1162                                         fetch_recurse = parse_fetch_recurse_submodules_arg(key, value);
1163                                 }
1164                                 free(key);
1165                         }
1166
1167                         if (fetch_recurse != RECURSE_SUBMODULES_NONE) {
1168                                 if (fetch_recurse == RECURSE_SUBMODULES_OFF)
1169                                         continue;
1170                                 if (fetch_recurse == RECURSE_SUBMODULES_ON_DEMAND) {
1171                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
1172                                                 continue;
1173                                         default_argv = "on-demand";
1174                                 }
1175                         } else {
1176                                 if (spf->default_option == RECURSE_SUBMODULES_OFF)
1177                                         continue;
1178                                 if (spf->default_option == RECURSE_SUBMODULES_ON_DEMAND) {
1179                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
1180                                                 continue;
1181                                         default_argv = "on-demand";
1182                                 }
1183                         }
1184                 } else if (spf->command_line_option == RECURSE_SUBMODULES_ON_DEMAND) {
1185                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
1186                                 continue;
1187                         default_argv = "on-demand";
1188                 }
1189
1190                 strbuf_addf(&submodule_path, "%s/%s", spf->work_tree, ce->name);
1191                 strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
1192                 strbuf_addf(&submodule_prefix, "%s%s/", spf->prefix, ce->name);
1193                 git_dir = read_gitfile(submodule_git_dir.buf);
1194                 if (!git_dir)
1195                         git_dir = submodule_git_dir.buf;
1196                 if (is_directory(git_dir)) {
1197                         child_process_init(cp);
1198                         cp->dir = strbuf_detach(&submodule_path, NULL);
1199                         prepare_submodule_repo_env(&cp->env_array);
1200                         cp->git_cmd = 1;
1201                         if (!spf->quiet)
1202                                 strbuf_addf(err, "Fetching submodule %s%s\n",
1203                                             spf->prefix, ce->name);
1204                         argv_array_init(&cp->args);
1205                         argv_array_pushv(&cp->args, spf->args.argv);
1206                         argv_array_push(&cp->args, default_argv);
1207                         argv_array_push(&cp->args, "--submodule-prefix");
1208                         argv_array_push(&cp->args, submodule_prefix.buf);
1209                         ret = 1;
1210                 }
1211                 strbuf_release(&submodule_path);
1212                 strbuf_release(&submodule_git_dir);
1213                 strbuf_release(&submodule_prefix);
1214                 if (ret) {
1215                         spf->count++;
1216                         return 1;
1217                 }
1218         }
1219         return 0;
1220 }
1221
1222 static int fetch_start_failure(struct strbuf *err,
1223                                void *cb, void *task_cb)
1224 {
1225         struct submodule_parallel_fetch *spf = cb;
1226
1227         spf->result = 1;
1228
1229         return 0;
1230 }
1231
1232 static int fetch_finish(int retvalue, struct strbuf *err,
1233                         void *cb, void *task_cb)
1234 {
1235         struct submodule_parallel_fetch *spf = cb;
1236
1237         if (retvalue)
1238                 spf->result = 1;
1239
1240         return 0;
1241 }
1242
1243 int fetch_populated_submodules(const struct argv_array *options,
1244                                const char *prefix, int command_line_option,
1245                                int default_option,
1246                                int quiet, int max_parallel_jobs)
1247 {
1248         int i;
1249         struct submodule_parallel_fetch spf = SPF_INIT;
1250
1251         spf.work_tree = get_git_work_tree();
1252         spf.command_line_option = command_line_option;
1253         spf.default_option = default_option;
1254         spf.quiet = quiet;
1255         spf.prefix = prefix;
1256
1257         if (!spf.work_tree)
1258                 goto out;
1259
1260         if (read_cache() < 0)
1261                 die("index file corrupt");
1262
1263         argv_array_push(&spf.args, "fetch");
1264         for (i = 0; i < options->argc; i++)
1265                 argv_array_push(&spf.args, options->argv[i]);
1266         argv_array_push(&spf.args, "--recurse-submodules-default");
1267         /* default value, "--submodule-prefix" and its value are added later */
1268
1269         calculate_changed_submodule_paths();
1270         run_processes_parallel(max_parallel_jobs,
1271                                get_next_submodule,
1272                                fetch_start_failure,
1273                                fetch_finish,
1274                                &spf);
1275
1276         argv_array_clear(&spf.args);
1277 out:
1278         string_list_clear(&changed_submodule_paths, 1);
1279         return spf.result;
1280 }
1281
1282 unsigned is_submodule_modified(const char *path, int ignore_untracked)
1283 {
1284         struct child_process cp = CHILD_PROCESS_INIT;
1285         struct strbuf buf = STRBUF_INIT;
1286         FILE *fp;
1287         unsigned dirty_submodule = 0;
1288         const char *git_dir;
1289         int ignore_cp_exit_code = 0;
1290
1291         strbuf_addf(&buf, "%s/.git", path);
1292         git_dir = read_gitfile(buf.buf);
1293         if (!git_dir)
1294                 git_dir = buf.buf;
1295         if (!is_git_directory(git_dir)) {
1296                 if (is_directory(git_dir))
1297                         die(_("'%s' not recognized as a git repository"), git_dir);
1298                 strbuf_release(&buf);
1299                 /* The submodule is not checked out, so it is not modified */
1300                 return 0;
1301         }
1302         strbuf_reset(&buf);
1303
1304         argv_array_pushl(&cp.args, "status", "--porcelain=2", NULL);
1305         if (ignore_untracked)
1306                 argv_array_push(&cp.args, "-uno");
1307
1308         prepare_submodule_repo_env(&cp.env_array);
1309         cp.git_cmd = 1;
1310         cp.no_stdin = 1;
1311         cp.out = -1;
1312         cp.dir = path;
1313         if (start_command(&cp))
1314                 die("Could not run 'git status --porcelain=2' in submodule %s", path);
1315
1316         fp = xfdopen(cp.out, "r");
1317         while (strbuf_getwholeline(&buf, fp, '\n') != EOF) {
1318                 /* regular untracked files */
1319                 if (buf.buf[0] == '?')
1320                         dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
1321
1322                 if (buf.buf[0] == 'u' ||
1323                     buf.buf[0] == '1' ||
1324                     buf.buf[0] == '2') {
1325                         /* T = line type, XY = status, SSSS = submodule state */
1326                         if (buf.len < strlen("T XY SSSS"))
1327                                 die("BUG: invalid status --porcelain=2 line %s",
1328                                     buf.buf);
1329
1330                         if (buf.buf[5] == 'S' && buf.buf[8] == 'U')
1331                                 /* nested untracked file */
1332                                 dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
1333
1334                         if (buf.buf[0] == 'u' ||
1335                             buf.buf[0] == '2' ||
1336                             memcmp(buf.buf + 5, "S..U", 4))
1337                                 /* other change */
1338                                 dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
1339                 }
1340
1341                 if ((dirty_submodule & DIRTY_SUBMODULE_MODIFIED) &&
1342                     ((dirty_submodule & DIRTY_SUBMODULE_UNTRACKED) ||
1343                      ignore_untracked)) {
1344                         /*
1345                          * We're not interested in any further information from
1346                          * the child any more, neither output nor its exit code.
1347                          */
1348                         ignore_cp_exit_code = 1;
1349                         break;
1350                 }
1351         }
1352         fclose(fp);
1353
1354         if (finish_command(&cp) && !ignore_cp_exit_code)
1355                 die("'git status --porcelain=2' failed in submodule %s", path);
1356
1357         strbuf_release(&buf);
1358         return dirty_submodule;
1359 }
1360
1361 int submodule_uses_gitfile(const char *path)
1362 {
1363         struct child_process cp = CHILD_PROCESS_INIT;
1364         const char *argv[] = {
1365                 "submodule",
1366                 "foreach",
1367                 "--quiet",
1368                 "--recursive",
1369                 "test -f .git",
1370                 NULL,
1371         };
1372         struct strbuf buf = STRBUF_INIT;
1373         const char *git_dir;
1374
1375         strbuf_addf(&buf, "%s/.git", path);
1376         git_dir = read_gitfile(buf.buf);
1377         if (!git_dir) {
1378                 strbuf_release(&buf);
1379                 return 0;
1380         }
1381         strbuf_release(&buf);
1382
1383         /* Now test that all nested submodules use a gitfile too */
1384         cp.argv = argv;
1385         prepare_submodule_repo_env(&cp.env_array);
1386         cp.git_cmd = 1;
1387         cp.no_stdin = 1;
1388         cp.no_stderr = 1;
1389         cp.no_stdout = 1;
1390         cp.dir = path;
1391         if (run_command(&cp))
1392                 return 0;
1393
1394         return 1;
1395 }
1396
1397 /*
1398  * Check if it is a bad idea to remove a submodule, i.e. if we'd lose data
1399  * when doing so.
1400  *
1401  * Return 1 if we'd lose data, return 0 if the removal is fine,
1402  * and negative values for errors.
1403  */
1404 int bad_to_remove_submodule(const char *path, unsigned flags)
1405 {
1406         ssize_t len;
1407         struct child_process cp = CHILD_PROCESS_INIT;
1408         struct strbuf buf = STRBUF_INIT;
1409         int ret = 0;
1410
1411         if (!file_exists(path) || is_empty_dir(path))
1412                 return 0;
1413
1414         if (!submodule_uses_gitfile(path))
1415                 return 1;
1416
1417         argv_array_pushl(&cp.args, "status", "--porcelain",
1418                                    "--ignore-submodules=none", NULL);
1419
1420         if (flags & SUBMODULE_REMOVAL_IGNORE_UNTRACKED)
1421                 argv_array_push(&cp.args, "-uno");
1422         else
1423                 argv_array_push(&cp.args, "-uall");
1424
1425         if (!(flags & SUBMODULE_REMOVAL_IGNORE_IGNORED_UNTRACKED))
1426                 argv_array_push(&cp.args, "--ignored");
1427
1428         prepare_submodule_repo_env(&cp.env_array);
1429         cp.git_cmd = 1;
1430         cp.no_stdin = 1;
1431         cp.out = -1;
1432         cp.dir = path;
1433         if (start_command(&cp)) {
1434                 if (flags & SUBMODULE_REMOVAL_DIE_ON_ERROR)
1435                         die(_("could not start 'git status' in submodule '%s'"),
1436                                 path);
1437                 ret = -1;
1438                 goto out;
1439         }
1440
1441         len = strbuf_read(&buf, cp.out, 1024);
1442         if (len > 2)
1443                 ret = 1;
1444         close(cp.out);
1445
1446         if (finish_command(&cp)) {
1447                 if (flags & SUBMODULE_REMOVAL_DIE_ON_ERROR)
1448                         die(_("could not run 'git status' in submodule '%s'"),
1449                                 path);
1450                 ret = -1;
1451         }
1452 out:
1453         strbuf_release(&buf);
1454         return ret;
1455 }
1456
1457 static const char *get_super_prefix_or_empty(void)
1458 {
1459         const char *s = get_super_prefix();
1460         if (!s)
1461                 s = "";
1462         return s;
1463 }
1464
1465 static int submodule_has_dirty_index(const struct submodule *sub)
1466 {
1467         struct child_process cp = CHILD_PROCESS_INIT;
1468
1469         prepare_submodule_repo_env(&cp.env_array);
1470
1471         cp.git_cmd = 1;
1472         argv_array_pushl(&cp.args, "diff-index", "--quiet",
1473                                    "--cached", "HEAD", NULL);
1474         cp.no_stdin = 1;
1475         cp.no_stdout = 1;
1476         cp.dir = sub->path;
1477         if (start_command(&cp))
1478                 die("could not recurse into submodule '%s'", sub->path);
1479
1480         return finish_command(&cp);
1481 }
1482
1483 static void submodule_reset_index(const char *path)
1484 {
1485         struct child_process cp = CHILD_PROCESS_INIT;
1486         prepare_submodule_repo_env(&cp.env_array);
1487
1488         cp.git_cmd = 1;
1489         cp.no_stdin = 1;
1490         cp.dir = path;
1491
1492         argv_array_pushf(&cp.args, "--super-prefix=%s%s/",
1493                                    get_super_prefix_or_empty(), path);
1494         argv_array_pushl(&cp.args, "read-tree", "-u", "--reset", NULL);
1495
1496         argv_array_push(&cp.args, EMPTY_TREE_SHA1_HEX);
1497
1498         if (run_command(&cp))
1499                 die("could not reset submodule index");
1500 }
1501
1502 /**
1503  * Moves a submodule at a given path from a given head to another new head.
1504  * For edge cases (a submodule coming into existence or removing a submodule)
1505  * pass NULL for old or new respectively.
1506  */
1507 int submodule_move_head(const char *path,
1508                          const char *old,
1509                          const char *new,
1510                          unsigned flags)
1511 {
1512         int ret = 0;
1513         struct child_process cp = CHILD_PROCESS_INIT;
1514         const struct submodule *sub;
1515         int *error_code_ptr, error_code;
1516
1517         if (!is_submodule_active(the_repository, path))
1518                 return 0;
1519
1520         if (flags & SUBMODULE_MOVE_HEAD_FORCE)
1521                 /*
1522                  * Pass non NULL pointer to is_submodule_populated_gently
1523                  * to prevent die()-ing. We'll use connect_work_tree_and_git_dir
1524                  * to fixup the submodule in the force case later.
1525                  */
1526                 error_code_ptr = &error_code;
1527         else
1528                 error_code_ptr = NULL;
1529
1530         if (old && !is_submodule_populated_gently(path, error_code_ptr))
1531                 return 0;
1532
1533         sub = submodule_from_path(&null_oid, path);
1534
1535         if (!sub)
1536                 die("BUG: could not get submodule information for '%s'", path);
1537
1538         if (old && !(flags & SUBMODULE_MOVE_HEAD_FORCE)) {
1539                 /* Check if the submodule has a dirty index. */
1540                 if (submodule_has_dirty_index(sub))
1541                         return error(_("submodule '%s' has dirty index"), path);
1542         }
1543
1544         if (!(flags & SUBMODULE_MOVE_HEAD_DRY_RUN)) {
1545                 if (old) {
1546                         if (!submodule_uses_gitfile(path))
1547                                 absorb_git_dir_into_superproject("", path,
1548                                         ABSORB_GITDIR_RECURSE_SUBMODULES);
1549                 } else {
1550                         char *gitdir = xstrfmt("%s/modules/%s",
1551                                     get_git_common_dir(), sub->name);
1552                         connect_work_tree_and_git_dir(path, gitdir);
1553                         free(gitdir);
1554
1555                         /* make sure the index is clean as well */
1556                         submodule_reset_index(path);
1557                 }
1558
1559                 if (old && (flags & SUBMODULE_MOVE_HEAD_FORCE)) {
1560                         char *gitdir = xstrfmt("%s/modules/%s",
1561                                     get_git_common_dir(), sub->name);
1562                         connect_work_tree_and_git_dir(path, gitdir);
1563                         free(gitdir);
1564                 }
1565         }
1566
1567         prepare_submodule_repo_env(&cp.env_array);
1568
1569         cp.git_cmd = 1;
1570         cp.no_stdin = 1;
1571         cp.dir = path;
1572
1573         argv_array_pushf(&cp.args, "--super-prefix=%s%s/",
1574                         get_super_prefix_or_empty(), path);
1575         argv_array_pushl(&cp.args, "read-tree", "--recurse-submodules", NULL);
1576
1577         if (flags & SUBMODULE_MOVE_HEAD_DRY_RUN)
1578                 argv_array_push(&cp.args, "-n");
1579         else
1580                 argv_array_push(&cp.args, "-u");
1581
1582         if (flags & SUBMODULE_MOVE_HEAD_FORCE)
1583                 argv_array_push(&cp.args, "--reset");
1584         else
1585                 argv_array_push(&cp.args, "-m");
1586
1587         argv_array_push(&cp.args, old ? old : EMPTY_TREE_SHA1_HEX);
1588         argv_array_push(&cp.args, new ? new : EMPTY_TREE_SHA1_HEX);
1589
1590         if (run_command(&cp)) {
1591                 ret = -1;
1592                 goto out;
1593         }
1594
1595         if (!(flags & SUBMODULE_MOVE_HEAD_DRY_RUN)) {
1596                 if (new) {
1597                         child_process_init(&cp);
1598                         /* also set the HEAD accordingly */
1599                         cp.git_cmd = 1;
1600                         cp.no_stdin = 1;
1601                         cp.dir = path;
1602
1603                         prepare_submodule_repo_env(&cp.env_array);
1604                         argv_array_pushl(&cp.args, "update-ref", "HEAD", new, NULL);
1605
1606                         if (run_command(&cp)) {
1607                                 ret = -1;
1608                                 goto out;
1609                         }
1610                 } else {
1611                         struct strbuf sb = STRBUF_INIT;
1612
1613                         strbuf_addf(&sb, "%s/.git", path);
1614                         unlink_or_warn(sb.buf);
1615                         strbuf_release(&sb);
1616
1617                         if (is_empty_dir(path))
1618                                 rmdir_or_warn(path);
1619                 }
1620         }
1621 out:
1622         return ret;
1623 }
1624
1625 static int find_first_merges(struct object_array *result, const char *path,
1626                 struct commit *a, struct commit *b)
1627 {
1628         int i, j;
1629         struct object_array merges = OBJECT_ARRAY_INIT;
1630         struct commit *commit;
1631         int contains_another;
1632
1633         char merged_revision[42];
1634         const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
1635                                    "--all", merged_revision, NULL };
1636         struct rev_info revs;
1637         struct setup_revision_opt rev_opts;
1638
1639         memset(result, 0, sizeof(struct object_array));
1640         memset(&rev_opts, 0, sizeof(rev_opts));
1641
1642         /* get all revisions that merge commit a */
1643         xsnprintf(merged_revision, sizeof(merged_revision), "^%s",
1644                         oid_to_hex(&a->object.oid));
1645         init_revisions(&revs, NULL);
1646         rev_opts.submodule = path;
1647         setup_revisions(ARRAY_SIZE(rev_args)-1, rev_args, &revs, &rev_opts);
1648
1649         /* save all revisions from the above list that contain b */
1650         if (prepare_revision_walk(&revs))
1651                 die("revision walk setup failed");
1652         while ((commit = get_revision(&revs)) != NULL) {
1653                 struct object *o = &(commit->object);
1654                 if (in_merge_bases(b, commit))
1655                         add_object_array(o, NULL, &merges);
1656         }
1657         reset_revision_walk();
1658
1659         /* Now we've got all merges that contain a and b. Prune all
1660          * merges that contain another found merge and save them in
1661          * result.
1662          */
1663         for (i = 0; i < merges.nr; i++) {
1664                 struct commit *m1 = (struct commit *) merges.objects[i].item;
1665
1666                 contains_another = 0;
1667                 for (j = 0; j < merges.nr; j++) {
1668                         struct commit *m2 = (struct commit *) merges.objects[j].item;
1669                         if (i != j && in_merge_bases(m2, m1)) {
1670                                 contains_another = 1;
1671                                 break;
1672                         }
1673                 }
1674
1675                 if (!contains_another)
1676                         add_object_array(merges.objects[i].item, NULL, result);
1677         }
1678
1679         free(merges.objects);
1680         return result->nr;
1681 }
1682
1683 static void print_commit(struct commit *commit)
1684 {
1685         struct strbuf sb = STRBUF_INIT;
1686         struct pretty_print_context ctx = {0};
1687         ctx.date_mode.type = DATE_NORMAL;
1688         format_commit_message(commit, " %h: %m %s", &sb, &ctx);
1689         fprintf(stderr, "%s\n", sb.buf);
1690         strbuf_release(&sb);
1691 }
1692
1693 #define MERGE_WARNING(path, msg) \
1694         warning("Failed to merge submodule %s (%s)", path, msg);
1695
1696 int merge_submodule(struct object_id *result, const char *path,
1697                     const struct object_id *base, const struct object_id *a,
1698                     const struct object_id *b, int search)
1699 {
1700         struct commit *commit_base, *commit_a, *commit_b;
1701         int parent_count;
1702         struct object_array merges;
1703
1704         int i;
1705
1706         /* store a in result in case we fail */
1707         oidcpy(result, a);
1708
1709         /* we can not handle deletion conflicts */
1710         if (is_null_oid(base))
1711                 return 0;
1712         if (is_null_oid(a))
1713                 return 0;
1714         if (is_null_oid(b))
1715                 return 0;
1716
1717         if (add_submodule_odb(path)) {
1718                 MERGE_WARNING(path, "not checked out");
1719                 return 0;
1720         }
1721
1722         if (!(commit_base = lookup_commit_reference(base)) ||
1723             !(commit_a = lookup_commit_reference(a)) ||
1724             !(commit_b = lookup_commit_reference(b))) {
1725                 MERGE_WARNING(path, "commits not present");
1726                 return 0;
1727         }
1728
1729         /* check whether both changes are forward */
1730         if (!in_merge_bases(commit_base, commit_a) ||
1731             !in_merge_bases(commit_base, commit_b)) {
1732                 MERGE_WARNING(path, "commits don't follow merge-base");
1733                 return 0;
1734         }
1735
1736         /* Case #1: a is contained in b or vice versa */
1737         if (in_merge_bases(commit_a, commit_b)) {
1738                 oidcpy(result, b);
1739                 return 1;
1740         }
1741         if (in_merge_bases(commit_b, commit_a)) {
1742                 oidcpy(result, a);
1743                 return 1;
1744         }
1745
1746         /*
1747          * Case #2: There are one or more merges that contain a and b in
1748          * the submodule. If there is only one, then present it as a
1749          * suggestion to the user, but leave it marked unmerged so the
1750          * user needs to confirm the resolution.
1751          */
1752
1753         /* Skip the search if makes no sense to the calling context.  */
1754         if (!search)
1755                 return 0;
1756
1757         /* find commit which merges them */
1758         parent_count = find_first_merges(&merges, path, commit_a, commit_b);
1759         switch (parent_count) {
1760         case 0:
1761                 MERGE_WARNING(path, "merge following commits not found");
1762                 break;
1763
1764         case 1:
1765                 MERGE_WARNING(path, "not fast-forward");
1766                 fprintf(stderr, "Found a possible merge resolution "
1767                                 "for the submodule:\n");
1768                 print_commit((struct commit *) merges.objects[0].item);
1769                 fprintf(stderr,
1770                         "If this is correct simply add it to the index "
1771                         "for example\n"
1772                         "by using:\n\n"
1773                         "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1774                         "which will accept this suggestion.\n",
1775                         oid_to_hex(&merges.objects[0].item->oid), path);
1776                 break;
1777
1778         default:
1779                 MERGE_WARNING(path, "multiple merges found");
1780                 for (i = 0; i < merges.nr; i++)
1781                         print_commit((struct commit *) merges.objects[i].item);
1782         }
1783
1784         free(merges.objects);
1785         return 0;
1786 }
1787
1788 /*
1789  * Embeds a single submodules git directory into the superprojects git dir,
1790  * non recursively.
1791  */
1792 static void relocate_single_git_dir_into_superproject(const char *prefix,
1793                                                       const char *path)
1794 {
1795         char *old_git_dir = NULL, *real_old_git_dir = NULL, *real_new_git_dir = NULL;
1796         const char *new_git_dir;
1797         const struct submodule *sub;
1798
1799         if (submodule_uses_worktrees(path))
1800                 die(_("relocate_gitdir for submodule '%s' with "
1801                       "more than one worktree not supported"), path);
1802
1803         old_git_dir = xstrfmt("%s/.git", path);
1804         if (read_gitfile(old_git_dir))
1805                 /* If it is an actual gitfile, it doesn't need migration. */
1806                 return;
1807
1808         real_old_git_dir = real_pathdup(old_git_dir, 1);
1809
1810         sub = submodule_from_path(&null_oid, path);
1811         if (!sub)
1812                 die(_("could not lookup name for submodule '%s'"), path);
1813
1814         new_git_dir = git_path("modules/%s", sub->name);
1815         if (safe_create_leading_directories_const(new_git_dir) < 0)
1816                 die(_("could not create directory '%s'"), new_git_dir);
1817         real_new_git_dir = real_pathdup(new_git_dir, 1);
1818
1819         fprintf(stderr, _("Migrating git directory of '%s%s' from\n'%s' to\n'%s'\n"),
1820                 get_super_prefix_or_empty(), path,
1821                 real_old_git_dir, real_new_git_dir);
1822
1823         relocate_gitdir(path, real_old_git_dir, real_new_git_dir);
1824
1825         free(old_git_dir);
1826         free(real_old_git_dir);
1827         free(real_new_git_dir);
1828 }
1829
1830 /*
1831  * Migrate the git directory of the submodule given by path from
1832  * having its git directory within the working tree to the git dir nested
1833  * in its superprojects git dir under modules/.
1834  */
1835 void absorb_git_dir_into_superproject(const char *prefix,
1836                                       const char *path,
1837                                       unsigned flags)
1838 {
1839         int err_code;
1840         const char *sub_git_dir;
1841         struct strbuf gitdir = STRBUF_INIT;
1842         strbuf_addf(&gitdir, "%s/.git", path);
1843         sub_git_dir = resolve_gitdir_gently(gitdir.buf, &err_code);
1844
1845         /* Not populated? */
1846         if (!sub_git_dir) {
1847                 const struct submodule *sub;
1848
1849                 if (err_code == READ_GITFILE_ERR_STAT_FAILED) {
1850                         /* unpopulated as expected */
1851                         strbuf_release(&gitdir);
1852                         return;
1853                 }
1854
1855                 if (err_code != READ_GITFILE_ERR_NOT_A_REPO)
1856                         /* We don't know what broke here. */
1857                         read_gitfile_error_die(err_code, path, NULL);
1858
1859                 /*
1860                 * Maybe populated, but no git directory was found?
1861                 * This can happen if the superproject is a submodule
1862                 * itself and was just absorbed. The absorption of the
1863                 * superproject did not rewrite the git file links yet,
1864                 * fix it now.
1865                 */
1866                 sub = submodule_from_path(&null_oid, path);
1867                 if (!sub)
1868                         die(_("could not lookup name for submodule '%s'"), path);
1869                 connect_work_tree_and_git_dir(path,
1870                         git_path("modules/%s", sub->name));
1871         } else {
1872                 /* Is it already absorbed into the superprojects git dir? */
1873                 char *real_sub_git_dir = real_pathdup(sub_git_dir, 1);
1874                 char *real_common_git_dir = real_pathdup(get_git_common_dir(), 1);
1875
1876                 if (!starts_with(real_sub_git_dir, real_common_git_dir))
1877                         relocate_single_git_dir_into_superproject(prefix, path);
1878
1879                 free(real_sub_git_dir);
1880                 free(real_common_git_dir);
1881         }
1882         strbuf_release(&gitdir);
1883
1884         if (flags & ABSORB_GITDIR_RECURSE_SUBMODULES) {
1885                 struct child_process cp = CHILD_PROCESS_INIT;
1886                 struct strbuf sb = STRBUF_INIT;
1887
1888                 if (flags & ~ABSORB_GITDIR_RECURSE_SUBMODULES)
1889                         die("BUG: we don't know how to pass the flags down?");
1890
1891                 strbuf_addstr(&sb, get_super_prefix_or_empty());
1892                 strbuf_addstr(&sb, path);
1893                 strbuf_addch(&sb, '/');
1894
1895                 cp.dir = path;
1896                 cp.git_cmd = 1;
1897                 cp.no_stdin = 1;
1898                 argv_array_pushl(&cp.args, "--super-prefix", sb.buf,
1899                                            "submodule--helper",
1900                                            "absorb-git-dirs", NULL);
1901                 prepare_submodule_repo_env(&cp.env_array);
1902                 if (run_command(&cp))
1903                         die(_("could not recurse into submodule '%s'"), path);
1904
1905                 strbuf_release(&sb);
1906         }
1907 }
1908
1909 const char *get_superproject_working_tree(void)
1910 {
1911         struct child_process cp = CHILD_PROCESS_INIT;
1912         struct strbuf sb = STRBUF_INIT;
1913         const char *one_up = real_path_if_valid("../");
1914         const char *cwd = xgetcwd();
1915         const char *ret = NULL;
1916         const char *subpath;
1917         int code;
1918         ssize_t len;
1919
1920         if (!is_inside_work_tree())
1921                 /*
1922                  * FIXME:
1923                  * We might have a superproject, but it is harder
1924                  * to determine.
1925                  */
1926                 return NULL;
1927
1928         if (!one_up)
1929                 return NULL;
1930
1931         subpath = relative_path(cwd, one_up, &sb);
1932
1933         prepare_submodule_repo_env(&cp.env_array);
1934         argv_array_pop(&cp.env_array);
1935
1936         argv_array_pushl(&cp.args, "--literal-pathspecs", "-C", "..",
1937                         "ls-files", "-z", "--stage", "--full-name", "--",
1938                         subpath, NULL);
1939         strbuf_reset(&sb);
1940
1941         cp.no_stdin = 1;
1942         cp.no_stderr = 1;
1943         cp.out = -1;
1944         cp.git_cmd = 1;
1945
1946         if (start_command(&cp))
1947                 die(_("could not start ls-files in .."));
1948
1949         len = strbuf_read(&sb, cp.out, PATH_MAX);
1950         close(cp.out);
1951
1952         if (starts_with(sb.buf, "160000")) {
1953                 int super_sub_len;
1954                 int cwd_len = strlen(cwd);
1955                 char *super_sub, *super_wt;
1956
1957                 /*
1958                  * There is a superproject having this repo as a submodule.
1959                  * The format is <mode> SP <hash> SP <stage> TAB <full name> \0,
1960                  * We're only interested in the name after the tab.
1961                  */
1962                 super_sub = strchr(sb.buf, '\t') + 1;
1963                 super_sub_len = sb.buf + sb.len - super_sub - 1;
1964
1965                 if (super_sub_len > cwd_len ||
1966                     strcmp(&cwd[cwd_len - super_sub_len], super_sub))
1967                         die (_("BUG: returned path string doesn't match cwd?"));
1968
1969                 super_wt = xstrdup(cwd);
1970                 super_wt[cwd_len - super_sub_len] = '\0';
1971
1972                 ret = real_path(super_wt);
1973                 free(super_wt);
1974         }
1975         strbuf_release(&sb);
1976
1977         code = finish_command(&cp);
1978
1979         if (code == 128)
1980                 /* '../' is not a git repository */
1981                 return NULL;
1982         if (code == 0 && len == 0)
1983                 /* There is an unrelated git repository at '../' */
1984                 return NULL;
1985         if (code)
1986                 die(_("ls-tree returned unexpected return code %d"), code);
1987
1988         return ret;
1989 }
1990
1991 int submodule_to_gitdir(struct strbuf *buf, const char *submodule)
1992 {
1993         const struct submodule *sub;
1994         const char *git_dir;
1995         int ret = 0;
1996
1997         strbuf_reset(buf);
1998         strbuf_addstr(buf, submodule);
1999         strbuf_complete(buf, '/');
2000         strbuf_addstr(buf, ".git");
2001
2002         git_dir = read_gitfile(buf->buf);
2003         if (git_dir) {
2004                 strbuf_reset(buf);
2005                 strbuf_addstr(buf, git_dir);
2006         }
2007         if (!is_git_directory(buf->buf)) {
2008                 sub = submodule_from_path(&null_oid, submodule);
2009                 if (!sub) {
2010                         ret = -1;
2011                         goto cleanup;
2012                 }
2013                 strbuf_reset(buf);
2014                 strbuf_git_path(buf, "%s/%s", "modules", sub->name);
2015         }
2016
2017 cleanup:
2018         return ret;
2019 }