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                 if (submodule->ignore)
 169                         handle_ignore_submodules_arg(diffopt, submodule->ignore);
 170                 else if (is_gitmodules_unmerged(&the_index))
 171                         DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
 172         }
 173 }
 174
 175 /* For loading from the .gitmodules file. */
 176 static int git_modules_config(const char *var, const char *value, void *cb)
 177 {
 178         if (starts_with(var, "submodule."))
 179                 return parse_submodule_config_option(var, value);
 180         return 0;
 181 }
 182
 183 /* Loads all submodule settings from the config. */
 184 int 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                 return 0;
 191         } else {
 192                 return git_modules_config(var, value, cb);
 193         }
 194 }
 195
 196 /* Cheap function that only determines if we're interested in submodules at all */
 197 int git_default_submodule_config(const char *var, const char *value, void *cb)
 198 {
 199         if (!strcmp(var, "submodule.recurse")) {
 200                 int v = git_config_bool(var, value) ?
 201                         RECURSE_SUBMODULES_ON : RECURSE_SUBMODULES_OFF;
 202                 config_update_recurse_submodules = v;
 203         }
 204         return 0;
 205 }
 206
 207 int option_parse_recurse_submodules_worktree_updater(const struct option *opt,
 208                                                      const char *arg, int unset)
 209 {
 210         if (unset) {
 211                 config_update_recurse_submodules = RECURSE_SUBMODULES_OFF;
 212                 return 0;
 213         }
 214         if (arg)
 215                 config_update_recurse_submodules =
 216                         parse_update_recurse_submodules_arg(opt->long_name,
 217                                                             arg);
 218         else
 219                 config_update_recurse_submodules = RECURSE_SUBMODULES_ON;
 220
 221         return 0;
 222 }
 223
 224 void load_submodule_cache(void)
 225 {
 226         if (config_update_recurse_submodules == RECURSE_SUBMODULES_OFF)
 227                 return;
 228
 229         gitmodules_config();
 230         git_config(submodule_config, NULL);
 231 }
 232
 233 static int gitmodules_cb(const char *var, const char *value, void *data)
 234 {
 235         struct repository *repo = data;
 236         return submodule_config_option(repo, var, value);
 237 }
 238
 239 void repo_read_gitmodules(struct repository *repo)
 240 {
 241         if (repo->worktree) {
 242                 char *gitmodules;
 243
 244                 if (repo_read_index(repo) < 0)
 245                         return;
 246
 247                 gitmodules = repo_worktree_path(repo, GITMODULES_FILE);
 248
 249                 if (!is_gitmodules_unmerged(repo->index))
 250                         git_config_from_file(gitmodules_cb, gitmodules, repo);
 251
 252                 free(gitmodules);
 253         }
 254 }
 255
 256 void gitmodules_config(void)
 257 {
 258         repo_read_gitmodules(the_repository);
 259 }
 260
 261 void gitmodules_config_oid(const struct object_id *commit_oid)
 262 {
 263         struct strbuf rev = STRBUF_INIT;
 264         struct object_id oid;
 265
 266         if (gitmodule_oid_from_commit(commit_oid, &oid, &rev)) {
 267                 git_config_from_blob_oid(submodule_config, rev.buf,
 268                                          &oid, NULL);
 269         }
 270         strbuf_release(&rev);
 271 }
 272
 273 /*
 274  * Determine if a submodule has been initialized at a given 'path'
 275  */
 276 int is_submodule_active(struct repository *repo, const char *path)
 277 {
 278         int ret = 0;
 279         char *key = NULL;
 280         char *value = NULL;
 281         const struct string_list *sl;
 282         const struct submodule *module;
 283
 284         module = submodule_from_cache(repo, &null_oid, path);
 285
 286         /* early return if there isn't a path->module mapping */
 287         if (!module)
 288                 return 0;
 289
 290         /* submodule.<name>.active is set */
 291         key = xstrfmt("submodule.%s.active", module->name);
 292         if (!repo_config_get_bool(repo, key, &ret)) {
 293                 free(key);
 294                 return ret;
 295         }
 296         free(key);
 297
 298         /* submodule.active is set */
 299         sl = repo_config_get_value_multi(repo, "submodule.active");
 300         if (sl) {
 301                 struct pathspec ps;
 302                 struct argv_array args = ARGV_ARRAY_INIT;
 303                 const struct string_list_item *item;
 304
 305                 for_each_string_list_item(item, sl) {
 306                         argv_array_push(&args, item->string);
 307                 }
 308
 309                 parse_pathspec(&ps, 0, 0, NULL, args.argv);
 310                 ret = match_pathspec(&ps, path, strlen(path), 0, NULL, 1);
 311
 312                 argv_array_clear(&args);
 313                 clear_pathspec(&ps);
 314                 return ret;
 315         }
 316
 317         /* fallback to checking if the URL is set */
 318         key = xstrfmt("submodule.%s.url", module->name);
 319         ret = !repo_config_get_string(repo, key, &value);
 320
 321         free(value);
 322         free(key);
 323         return ret;
 324 }
 325
 326 int is_submodule_populated_gently(const char *path, int *return_error_code)
 327 {
 328         int ret = 0;
 329         char *gitdir = xstrfmt("%s/.git", path);
 330
 331         if (resolve_gitdir_gently(gitdir, return_error_code))
 332                 ret = 1;
 333
 334         free(gitdir);
 335         return ret;
 336 }
 337
 338 /*
 339  * Dies if the provided 'prefix' corresponds to an unpopulated submodule
 340  */
 341 void die_in_unpopulated_submodule(const struct index_state *istate,
 342                                   const char *prefix)
 343 {
 344         int i, prefixlen;
 345
 346         if (!prefix)
 347                 return;
 348
 349         prefixlen = strlen(prefix);
 350
 351         for (i = 0; i < istate->cache_nr; i++) {
 352                 struct cache_entry *ce = istate->cache[i];
 353                 int ce_len = ce_namelen(ce);
 354
 355                 if (!S_ISGITLINK(ce->ce_mode))
 356                         continue;
 357                 if (prefixlen <= ce_len)
 358                         continue;
 359                 if (strncmp(ce->name, prefix, ce_len))
 360                         continue;
 361                 if (prefix[ce_len] != '/')
 362                         continue;
 363
 364                 die(_("in unpopulated submodule '%s'"), ce->name);
 365         }
 366 }
 367
 368 /*
 369  * Dies if any paths in the provided pathspec descends into a submodule
 370  */
 371 void die_path_inside_submodule(const struct index_state *istate,
 372                                const struct pathspec *ps)
 373 {
 374         int i, j;
 375
 376         for (i = 0; i < istate->cache_nr; i++) {
 377                 struct cache_entry *ce = istate->cache[i];
 378                 int ce_len = ce_namelen(ce);
 379
 380                 if (!S_ISGITLINK(ce->ce_mode))
 381                         continue;
 382
 383                 for (j = 0; j < ps->nr ; j++) {
 384                         const struct pathspec_item *item = &ps->items[j];
 385
 386                         if (item->len <= ce_len)
 387                                 continue;
 388                         if (item->match[ce_len] != '/')
 389                                 continue;
 390                         if (strncmp(ce->name, item->match, ce_len))
 391                                 continue;
 392                         if (item->len == ce_len + 1)
 393                                 continue;
 394
 395                         die(_("Pathspec '%s' is in submodule '%.*s'"),
 396                             item->original, ce_len, ce->name);
 397                 }
 398         }
 399 }
 400
 401 int parse_submodule_update_strategy(const char *value,
 402                 struct submodule_update_strategy *dst)
 403 {
 404         free((void*)dst->command);
 405         dst->command = NULL;
 406         if (!strcmp(value, "none"))
 407                 dst->type = SM_UPDATE_NONE;
 408         else if (!strcmp(value, "checkout"))
 409                 dst->type = SM_UPDATE_CHECKOUT;
 410         else if (!strcmp(value, "rebase"))
 411                 dst->type = SM_UPDATE_REBASE;
 412         else if (!strcmp(value, "merge"))
 413                 dst->type = SM_UPDATE_MERGE;
 414         else if (skip_prefix(value, "!", &value)) {
 415                 dst->type = SM_UPDATE_COMMAND;
 416                 dst->command = xstrdup(value);
 417         } else
 418                 return -1;
 419         return 0;
 420 }
 421
 422 const char *submodule_strategy_to_string(const struct submodule_update_strategy *s)
 423 {
 424         struct strbuf sb = STRBUF_INIT;
 425         switch (s->type) {
 426         case SM_UPDATE_CHECKOUT:
 427                 return "checkout";
 428         case SM_UPDATE_MERGE:
 429                 return "merge";
 430         case SM_UPDATE_REBASE:
 431                 return "rebase";
 432         case SM_UPDATE_NONE:
 433                 return "none";
 434         case SM_UPDATE_UNSPECIFIED:
 435                 return NULL;
 436         case SM_UPDATE_COMMAND:
 437                 strbuf_addf(&sb, "!%s", s->command);
 438                 return strbuf_detach(&sb, NULL);
 439         }
 440         return NULL;
 441 }
 442
 443 void handle_ignore_submodules_arg(struct diff_options *diffopt,
 444                                   const char *arg)
 445 {
 446         DIFF_OPT_CLR(diffopt, IGNORE_SUBMODULES);
 447         DIFF_OPT_CLR(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 448         DIFF_OPT_CLR(diffopt, IGNORE_DIRTY_SUBMODULES);
 449
 450         if (!strcmp(arg, "all"))
 451                 DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
 452         else if (!strcmp(arg, "untracked"))
 453                 DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 454         else if (!strcmp(arg, "dirty"))
 455                 DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES);
 456         else if (strcmp(arg, "none"))
 457                 die("bad --ignore-submodules argument: %s", arg);
 458 }
 459
 460 static int prepare_submodule_summary(struct rev_info *rev, const char *path,
 461                 struct commit *left, struct commit *right,
 462                 struct commit_list *merge_bases)
 463 {
 464         struct commit_list *list;
 465
 466         init_revisions(rev, NULL);
 467         setup_revisions(0, NULL, rev, NULL);
 468         rev->left_right = 1;
 469         rev->first_parent_only = 1;
 470         left->object.flags |= SYMMETRIC_LEFT;
 471         add_pending_object(rev, &left->object, path);
 472         add_pending_object(rev, &right->object, path);
 473         for (list = merge_bases; list; list = list->next) {
 474                 list->item->object.flags |= UNINTERESTING;
 475                 add_pending_object(rev, &list->item->object,
 476                         oid_to_hex(&list->item->object.oid));
 477         }
 478         return prepare_revision_walk(rev);
 479 }
 480
 481 static void print_submodule_summary(struct rev_info *rev, struct diff_options *o)
 482 {
 483         static const char format[] = "  %m %s";
 484         struct strbuf sb = STRBUF_INIT;
 485         struct commit *commit;
 486
 487         while ((commit = get_revision(rev))) {
 488                 struct pretty_print_context ctx = {0};
 489                 ctx.date_mode = rev->date_mode;
 490                 ctx.output_encoding = get_log_output_encoding();
 491                 strbuf_setlen(&sb, 0);
 492                 format_commit_message(commit, format, &sb, &ctx);
 493                 strbuf_addch(&sb, '\n');
 494                 if (commit->object.flags & SYMMETRIC_LEFT)
 495                         diff_emit_submodule_del(o, sb.buf);
 496                 else
 497                         diff_emit_submodule_add(o, sb.buf);
 498         }
 499         strbuf_release(&sb);
 500 }
 501
 502 static void prepare_submodule_repo_env_no_git_dir(struct argv_array *out)
 503 {
 504         const char * const *var;
 505
 506         for (var = local_repo_env; *var; var++) {
 507                 if (strcmp(*var, CONFIG_DATA_ENVIRONMENT))
 508                         argv_array_push(out, *var);
 509         }
 510 }
 511
 512 void prepare_submodule_repo_env(struct argv_array *out)
 513 {
 514         prepare_submodule_repo_env_no_git_dir(out);
 515         argv_array_pushf(out, "%s=%s", GIT_DIR_ENVIRONMENT,
 516                          DEFAULT_GIT_DIR_ENVIRONMENT);
 517 }
 518
 519 /* Helper function to display the submodule header line prior to the full
 520  * summary output. If it can locate the submodule objects directory it will
 521  * attempt to lookup both the left and right commits and put them into the
 522  * left and right pointers.
 523  */
 524 static void show_submodule_header(struct diff_options *o, const char *path,
 525                 struct object_id *one, struct object_id *two,
 526                 unsigned dirty_submodule,
 527                 struct commit **left, struct commit **right,
 528                 struct commit_list **merge_bases)
 529 {
 530         const char *message = NULL;
 531         struct strbuf sb = STRBUF_INIT;
 532         int fast_forward = 0, fast_backward = 0;
 533
 534         if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
 535                 diff_emit_submodule_untracked(o, path);
 536
 537         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
 538                 diff_emit_submodule_modified(o, path);
 539
 540         if (is_null_oid(one))
 541                 message = "(new submodule)";
 542         else if (is_null_oid(two))
 543                 message = "(submodule deleted)";
 544
 545         if (add_submodule_odb(path)) {
 546                 if (!message)
 547                         message = "(not initialized)";
 548                 goto output_header;
 549         }
 550
 551         /*
 552          * Attempt to lookup the commit references, and determine if this is
 553          * a fast forward or fast backwards update.
 554          */
 555         *left = lookup_commit_reference(one);
 556         *right = lookup_commit_reference(two);
 557
 558         /*
 559          * Warn about missing commits in the submodule project, but only if
 560          * they aren't null.
 561          */
 562         if ((!is_null_oid(one) && !*left) ||
 563              (!is_null_oid(two) && !*right))
 564                 message = "(commits not present)";
 565
 566         *merge_bases = get_merge_bases(*left, *right);
 567         if (*merge_bases) {
 568                 if ((*merge_bases)->item == *left)
 569                         fast_forward = 1;
 570                 else if ((*merge_bases)->item == *right)
 571                         fast_backward = 1;
 572         }
 573
 574         if (!oidcmp(one, two)) {
 575                 strbuf_release(&sb);
 576                 return;
 577         }
 578
 579 output_header:
 580         strbuf_addf(&sb, "Submodule %s ", path);
 581         strbuf_add_unique_abbrev(&sb, one->hash, DEFAULT_ABBREV);
 582         strbuf_addstr(&sb, (fast_backward || fast_forward) ? ".." : "...");
 583         strbuf_add_unique_abbrev(&sb, two->hash, DEFAULT_ABBREV);
 584         if (message)
 585                 strbuf_addf(&sb, " %s\n", message);
 586         else
 587                 strbuf_addf(&sb, "%s:\n", fast_backward ? " (rewind)" : "");
 588         diff_emit_submodule_header(o, sb.buf);
 589
 590         strbuf_release(&sb);
 591 }
 592
 593 void show_submodule_summary(struct diff_options *o, const char *path,
 594                 struct object_id *one, struct object_id *two,
 595                 unsigned dirty_submodule)
 596 {
 597         struct rev_info rev;
 598         struct commit *left = NULL, *right = NULL;
 599         struct commit_list *merge_bases = NULL;
 600
 601         show_submodule_header(o, path, one, two, dirty_submodule,
 602                               &left, &right, &merge_bases);
 603
 604         /*
 605          * If we don't have both a left and a right pointer, there is no
 606          * reason to try and display a summary. The header line should contain
 607          * all the information the user needs.
 608          */
 609         if (!left || !right)
 610                 goto out;
 611
 612         /* Treat revision walker failure the same as missing commits */
 613         if (prepare_submodule_summary(&rev, path, left, right, merge_bases)) {
 614                 diff_emit_submodule_error(o, "(revision walker failed)\n");
 615                 goto out;
 616         }
 617
 618         print_submodule_summary(&rev, o);
 619
 620 out:
 621         if (merge_bases)
 622                 free_commit_list(merge_bases);
 623         clear_commit_marks(left, ~0);
 624         clear_commit_marks(right, ~0);
 625 }
 626
 627 void show_submodule_inline_diff(struct diff_options *o, const char *path,
 628                 struct object_id *one, struct object_id *two,
 629                 unsigned dirty_submodule)
 630 {
 631         const struct object_id *old = &empty_tree_oid, *new = &empty_tree_oid;
 632         struct commit *left = NULL, *right = NULL;
 633         struct commit_list *merge_bases = NULL;
 634         struct child_process cp = CHILD_PROCESS_INIT;
 635         struct strbuf sb = STRBUF_INIT;
 636
 637         show_submodule_header(o, path, one, two, dirty_submodule,
 638                               &left, &right, &merge_bases);
 639
 640         /* We need a valid left and right commit to display a difference */
 641         if (!(left || is_null_oid(one)) ||
 642             !(right || is_null_oid(two)))
 643                 goto done;
 644
 645         if (left)
 646                 old = one;
 647         if (right)
 648                 new = two;
 649
 650         cp.git_cmd = 1;
 651         cp.dir = path;
 652         cp.out = -1;
 653         cp.no_stdin = 1;
 654
 655         /* TODO: other options may need to be passed here. */
 656         argv_array_pushl(&cp.args, "diff", "--submodule=diff", NULL);
 657         argv_array_pushf(&cp.args, "--color=%s", want_color(o->use_color) ?
 658                          "always" : "never");
 659
 660         if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
 661                 argv_array_pushf(&cp.args, "--src-prefix=%s%s/",
 662                                  o->b_prefix, path);
 663                 argv_array_pushf(&cp.args, "--dst-prefix=%s%s/",
 664                                  o->a_prefix, path);
 665         } else {
 666                 argv_array_pushf(&cp.args, "--src-prefix=%s%s/",
 667                                  o->a_prefix, path);
 668                 argv_array_pushf(&cp.args, "--dst-prefix=%s%s/",
 669                                  o->b_prefix, path);
 670         }
 671         argv_array_push(&cp.args, oid_to_hex(old));
 672         /*
 673          * If the submodule has modified content, we will diff against the
 674          * work tree, under the assumption that the user has asked for the
 675          * diff format and wishes to actually see all differences even if they
 676          * haven't yet been committed to the submodule yet.
 677          */
 678         if (!(dirty_submodule & DIRTY_SUBMODULE_MODIFIED))
 679                 argv_array_push(&cp.args, oid_to_hex(new));
 680
 681         prepare_submodule_repo_env(&cp.env_array);
 682         if (start_command(&cp))
 683                 diff_emit_submodule_error(o, "(diff failed)\n");
 684
 685         while (strbuf_getwholeline_fd(&sb, cp.out, '\n') != EOF)
 686                 diff_emit_submodule_pipethrough(o, sb.buf, sb.len);
 687
 688         if (finish_command(&cp))
 689                 diff_emit_submodule_error(o, "(diff failed)\n");
 690
 691 done:
 692         strbuf_release(&sb);
 693         if (merge_bases)
 694                 free_commit_list(merge_bases);
 695         if (left)
 696                 clear_commit_marks(left, ~0);
 697         if (right)
 698                 clear_commit_marks(right, ~0);
 699 }
 700
 701 int should_update_submodules(void)
 702 {
 703         return config_update_recurse_submodules == RECURSE_SUBMODULES_ON;
 704 }
 705
 706 const struct submodule *submodule_from_ce(const struct cache_entry *ce)
 707 {
 708         if (!S_ISGITLINK(ce->ce_mode))
 709                 return NULL;
 710
 711         if (!should_update_submodules())
 712                 return NULL;
 713
 714         return submodule_from_path(&null_oid, ce->name);
 715 }
 716
 717 static struct oid_array *submodule_commits(struct string_list *submodules,
 718                                            const char *path)
 719 {
 720         struct string_list_item *item;
 721
 722         item = string_list_insert(submodules, path);
 723         if (item->util)
 724                 return (struct oid_array *) item->util;
 725
 726         /* NEEDSWORK: should we have oid_array_init()? */
 727         item->util = xcalloc(1, sizeof(struct oid_array));
 728         return (struct oid_array *) item->util;
 729 }
 730
 731 static void collect_changed_submodules_cb(struct diff_queue_struct *q,
 732                                           struct diff_options *options,
 733                                           void *data)
 734 {
 735         int i;
 736         struct string_list *changed = data;
 737
 738         for (i = 0; i < q->nr; i++) {
 739                 struct diff_filepair *p = q->queue[i];
 740                 struct oid_array *commits;
 741                 if (!S_ISGITLINK(p->two->mode))
 742                         continue;
 743
 744                 if (S_ISGITLINK(p->one->mode)) {
 745                         /*
 746                          * NEEDSWORK: We should honor the name configured in
 747                          * the .gitmodules file of the commit we are examining
 748                          * here to be able to correctly follow submodules
 749                          * being moved around.
 750                          */
 751                         commits = submodule_commits(changed, p->two->path);
 752                         oid_array_append(commits, &p->two->oid);
 753                 } else {
 754                         /* Submodule is new or was moved here */
 755                         /*
 756                          * NEEDSWORK: When the .git directories of submodules
 757                          * live inside the superprojects .git directory some
 758                          * day we should fetch new submodules directly into
 759                          * that location too when config or options request
 760                          * that so they can be checked out from there.
 761                          */
 762                         continue;
 763                 }
 764         }
 765 }
 766
 767 /*
 768  * Collect the paths of submodules in 'changed' which have changed based on
 769  * the revisions as specified in 'argv'.  Each entry in 'changed' will also
 770  * have a corresponding 'struct oid_array' (in the 'util' field) which lists
 771  * what the submodule pointers were updated to during the change.
 772  */
 773 static void collect_changed_submodules(struct string_list *changed,
 774                                        struct argv_array *argv)
 775 {
 776         struct rev_info rev;
 777         const struct commit *commit;
 778
 779         init_revisions(&rev, NULL);
 780         setup_revisions(argv->argc, argv->argv, &rev, NULL);
 781         if (prepare_revision_walk(&rev))
 782                 die("revision walk setup failed");
 783
 784         while ((commit = get_revision(&rev))) {
 785                 struct rev_info diff_rev;
 786
 787                 init_revisions(&diff_rev, NULL);
 788                 diff_rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
 789                 diff_rev.diffopt.format_callback = collect_changed_submodules_cb;
 790                 diff_rev.diffopt.format_callback_data = changed;
 791                 diff_tree_combined_merge(commit, 1, &diff_rev);
 792         }
 793
 794         reset_revision_walk();
 795 }
 796
 797 static void free_submodules_oids(struct string_list *submodules)
 798 {
 799         struct string_list_item *item;
 800         for_each_string_list_item(item, submodules)
 801                 oid_array_clear((struct oid_array *) item->util);
 802         string_list_clear(submodules, 1);
 803 }
 804
 805 static int has_remote(const char *refname, const struct object_id *oid,
 806                       int flags, void *cb_data)
 807 {
 808         return 1;
 809 }
 810
 811 static int append_oid_to_argv(const struct object_id *oid, void *data)
 812 {
 813         struct argv_array *argv = data;
 814         argv_array_push(argv, oid_to_hex(oid));
 815         return 0;
 816 }
 817
 818 static int check_has_commit(const struct object_id *oid, void *data)
 819 {
 820         int *has_commit = data;
 821
 822         if (!lookup_commit_reference(oid))
 823                 *has_commit = 0;
 824
 825         return 0;
 826 }
 827
 828 static int submodule_has_commits(const char *path, struct oid_array *commits)
 829 {
 830         int has_commit = 1;
 831
 832         /*
 833          * Perform a cheap, but incorrect check for the existence of 'commits'.
 834          * This is done by adding the submodule's object store to the in-core
 835          * object store, and then querying for each commit's existence.  If we
 836          * do not have the commit object anywhere, there is no chance we have
 837          * it in the object store of the correct submodule and have it
 838          * reachable from a ref, so we can fail early without spawning rev-list
 839          * which is expensive.
 840          */
 841         if (add_submodule_odb(path))
 842                 return 0;
 843
 844         oid_array_for_each_unique(commits, check_has_commit, &has_commit);
 845
 846         if (has_commit) {
 847                 /*
 848                  * Even if the submodule is checked out and the commit is
 849                  * present, make sure it exists in the submodule's object store
 850                  * and that it is reachable from a ref.
 851                  */
 852                 struct child_process cp = CHILD_PROCESS_INIT;
 853                 struct strbuf out = STRBUF_INIT;
 854
 855                 argv_array_pushl(&cp.args, "rev-list", "-n", "1", NULL);
 856                 oid_array_for_each_unique(commits, append_oid_to_argv, &cp.args);
 857                 argv_array_pushl(&cp.args, "--not", "--all", NULL);
 858
 859                 prepare_submodule_repo_env(&cp.env_array);
 860                 cp.git_cmd = 1;
 861                 cp.no_stdin = 1;
 862                 cp.dir = path;
 863
 864                 if (capture_command(&cp, &out, GIT_MAX_HEXSZ + 1) || out.len)
 865                         has_commit = 0;
 866
 867                 strbuf_release(&out);
 868         }
 869
 870         return has_commit;
 871 }
 872
 873 static int submodule_needs_pushing(const char *path, struct oid_array *commits)
 874 {
 875         if (!submodule_has_commits(path, commits))
 876                 /*
 877                  * NOTE: We do consider it safe to return "no" here. The
 878                  * correct answer would be "We do not know" instead of
 879                  * "No push needed", but it is quite hard to change
 880                  * the submodule pointer without having the submodule
 881                  * around. If a user did however change the submodules
 882                  * without having the submodule around, this indicates
 883                  * an expert who knows what they are doing or a
 884                  * maintainer integrating work from other people. In
 885                  * both cases it should be safe to skip this check.
 886                  */
 887                 return 0;
 888
 889         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 890                 struct child_process cp = CHILD_PROCESS_INIT;
 891                 struct strbuf buf = STRBUF_INIT;
 892                 int needs_pushing = 0;
 893
 894                 argv_array_push(&cp.args, "rev-list");
 895                 oid_array_for_each_unique(commits, append_oid_to_argv, &cp.args);
 896                 argv_array_pushl(&cp.args, "--not", "--remotes", "-n", "1" , NULL);
 897
 898                 prepare_submodule_repo_env(&cp.env_array);
 899                 cp.git_cmd = 1;
 900                 cp.no_stdin = 1;
 901                 cp.out = -1;
 902                 cp.dir = path;
 903                 if (start_command(&cp))
 904                         die("Could not run 'git rev-list <commits> --not --remotes -n 1' command in submodule %s",
 905                                         path);
 906                 if (strbuf_read(&buf, cp.out, 41))
 907                         needs_pushing = 1;
 908                 finish_command(&cp);
 909                 close(cp.out);
 910                 strbuf_release(&buf);
 911                 return needs_pushing;
 912         }
 913
 914         return 0;
 915 }
 916
 917 int find_unpushed_submodules(struct oid_array *commits,
 918                 const char *remotes_name, struct string_list *needs_pushing)
 919 {
 920         struct string_list submodules = STRING_LIST_INIT_DUP;
 921         struct string_list_item *submodule;
 922         struct argv_array argv = ARGV_ARRAY_INIT;
 923
 924         /* argv.argv[0] will be ignored by setup_revisions */
 925         argv_array_push(&argv, "find_unpushed_submodules");
 926         oid_array_for_each_unique(commits, append_oid_to_argv, &argv);
 927         argv_array_push(&argv, "--not");
 928         argv_array_pushf(&argv, "--remotes=%s", remotes_name);
 929
 930         collect_changed_submodules(&submodules, &argv);
 931
 932         for_each_string_list_item(submodule, &submodules) {
 933                 struct oid_array *commits = submodule->util;
 934                 const char *path = submodule->string;
 935
 936                 if (submodule_needs_pushing(path, commits))
 937                         string_list_insert(needs_pushing, path);
 938         }
 939
 940         free_submodules_oids(&submodules);
 941         argv_array_clear(&argv);
 942
 943         return needs_pushing->nr;
 944 }
 945
 946 static int push_submodule(const char *path,
 947                           const struct remote *remote,
 948                           const char **refspec, int refspec_nr,
 949                           const struct string_list *push_options,
 950                           int dry_run)
 951 {
 952         if (add_submodule_odb(path))
 953                 return 1;
 954
 955         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 956                 struct child_process cp = CHILD_PROCESS_INIT;
 957                 argv_array_push(&cp.args, "push");
 958                 if (dry_run)
 959                         argv_array_push(&cp.args, "--dry-run");
 960
 961                 if (push_options && push_options->nr) {
 962                         const struct string_list_item *item;
 963                         for_each_string_list_item(item, push_options)
 964                                 argv_array_pushf(&cp.args, "--push-option=%s",
 965                                                  item->string);
 966                 }
 967
 968                 if (remote->origin != REMOTE_UNCONFIGURED) {
 969                         int i;
 970                         argv_array_push(&cp.args, remote->name);
 971                         for (i = 0; i < refspec_nr; i++)
 972                                 argv_array_push(&cp.args, refspec[i]);
 973                 }
 974
 975                 prepare_submodule_repo_env(&cp.env_array);
 976                 cp.git_cmd = 1;
 977                 cp.no_stdin = 1;
 978                 cp.dir = path;
 979                 if (run_command(&cp))
 980                         return 0;
 981                 close(cp.out);
 982         }
 983
 984         return 1;
 985 }
 986
 987 /*
 988  * Perform a check in the submodule to see if the remote and refspec work.
 989  * Die if the submodule can't be pushed.
 990  */
 991 static void submodule_push_check(const char *path, const char *head,
 992                                  const struct remote *remote,
 993                                  const char **refspec, int refspec_nr)
 994 {
 995         struct child_process cp = CHILD_PROCESS_INIT;
 996         int i;
 997
 998         argv_array_push(&cp.args, "submodule--helper");
 999         argv_array_push(&cp.args, "push-check");
1000         argv_array_push(&cp.args, head);
1001         argv_array_push(&cp.args, remote->name);
1002
1003         for (i = 0; i < refspec_nr; i++)
1004                 argv_array_push(&cp.args, refspec[i]);
1005
1006         prepare_submodule_repo_env(&cp.env_array);
1007         cp.git_cmd = 1;
1008         cp.no_stdin = 1;
1009         cp.no_stdout = 1;
1010         cp.dir = path;
1011
1012         /*
1013          * Simply indicate if 'submodule--helper push-check' failed.
1014          * More detailed error information will be provided by the
1015          * child process.
1016          */
1017         if (run_command(&cp))
1018                 die("process for submodule '%s' failed", path);
1019 }
1020
1021 int push_unpushed_submodules(struct oid_array *commits,
1022                              const struct remote *remote,
1023                              const char **refspec, int refspec_nr,
1024                              const struct string_list *push_options,
1025                              int dry_run)
1026 {
1027         int i, ret = 1;
1028         struct string_list needs_pushing = STRING_LIST_INIT_DUP;
1029
1030         if (!find_unpushed_submodules(commits, remote->name, &needs_pushing))
1031                 return 1;
1032
1033         /*
1034          * Verify that the remote and refspec can be propagated to all
1035          * submodules.  This check can be skipped if the remote and refspec
1036          * won't be propagated due to the remote being unconfigured (e.g. a URL
1037          * instead of a remote name).
1038          */
1039         if (remote->origin != REMOTE_UNCONFIGURED) {
1040                 char *head;
1041                 struct object_id head_oid;
1042
1043                 head = resolve_refdup("HEAD", 0, head_oid.hash, NULL);
1044                 if (!head)
1045                         die(_("Failed to resolve HEAD as a valid ref."));
1046
1047                 for (i = 0; i < needs_pushing.nr; i++)
1048                         submodule_push_check(needs_pushing.items[i].string,
1049                                              head, remote,
1050                                              refspec, refspec_nr);
1051                 free(head);
1052         }
1053
1054         /* Actually push the submodules */
1055         for (i = 0; i < needs_pushing.nr; i++) {
1056                 const char *path = needs_pushing.items[i].string;
1057                 fprintf(stderr, "Pushing submodule '%s'\n", path);
1058                 if (!push_submodule(path, remote, refspec, refspec_nr,
1059                                     push_options, dry_run)) {
1060                         fprintf(stderr, "Unable to push submodule '%s'\n", path);
1061                         ret = 0;
1062                 }
1063         }
1064
1065         string_list_clear(&needs_pushing, 0);
1066
1067         return ret;
1068 }
1069
1070 static int append_oid_to_array(const char *ref, const struct object_id *oid,
1071                                int flags, void *data)
1072 {
1073         struct oid_array *array = data;
1074         oid_array_append(array, oid);
1075         return 0;
1076 }
1077
1078 void check_for_new_submodule_commits(struct object_id *oid)
1079 {
1080         if (!initialized_fetch_ref_tips) {
1081                 for_each_ref(append_oid_to_array, &ref_tips_before_fetch);
1082                 initialized_fetch_ref_tips = 1;
1083         }
1084
1085         oid_array_append(&ref_tips_after_fetch, oid);
1086 }
1087
1088 static void calculate_changed_submodule_paths(void)
1089 {
1090         struct argv_array argv = ARGV_ARRAY_INIT;
1091         struct string_list changed_submodules = STRING_LIST_INIT_DUP;
1092         const struct string_list_item *item;
1093
1094         /* No need to check if there are no submodules configured */
1095         if (!submodule_from_path(NULL, NULL))
1096                 return;
1097
1098         argv_array_push(&argv, "--"); /* argv[0] program name */
1099         oid_array_for_each_unique(&ref_tips_after_fetch,
1100                                    append_oid_to_argv, &argv);
1101         argv_array_push(&argv, "--not");
1102         oid_array_for_each_unique(&ref_tips_before_fetch,
1103                                    append_oid_to_argv, &argv);
1104
1105         /*
1106          * Collect all submodules (whether checked out or not) for which new
1107          * commits have been recorded upstream in "changed_submodule_paths".
1108          */
1109         collect_changed_submodules(&changed_submodules, &argv);
1110
1111         for_each_string_list_item(item, &changed_submodules) {
1112                 struct oid_array *commits = item->util;
1113                 const char *path = item->string;
1114
1115                 if (!submodule_has_commits(path, commits))
1116                         string_list_append(&changed_submodule_paths, path);
1117         }
1118
1119         free_submodules_oids(&changed_submodules);
1120         argv_array_clear(&argv);
1121         oid_array_clear(&ref_tips_before_fetch);
1122         oid_array_clear(&ref_tips_after_fetch);
1123         initialized_fetch_ref_tips = 0;
1124 }
1125
1126 int submodule_touches_in_range(struct object_id *excl_oid,
1127                                struct object_id *incl_oid)
1128 {
1129         struct string_list subs = STRING_LIST_INIT_DUP;
1130         struct argv_array args = ARGV_ARRAY_INIT;
1131         int ret;
1132
1133         gitmodules_config();
1134         /* No need to check if there are no submodules configured */
1135         if (!submodule_from_path(NULL, NULL))
1136                 return 0;
1137
1138         argv_array_push(&args, "--"); /* args[0] program name */
1139         argv_array_push(&args, oid_to_hex(incl_oid));
1140         argv_array_push(&args, "--not");
1141         argv_array_push(&args, oid_to_hex(excl_oid));
1142
1143         collect_changed_submodules(&subs, &args);
1144         ret = subs.nr;
1145
1146         argv_array_clear(&args);
1147
1148         free_submodules_oids(&subs);
1149         return ret;
1150 }
1151
1152 struct submodule_parallel_fetch {
1153         int count;
1154         struct argv_array args;
1155         const char *work_tree;
1156         const char *prefix;
1157         int command_line_option;
1158         int default_option;
1159         int quiet;
1160         int result;
1161 };
1162 #define SPF_INIT {0, ARGV_ARRAY_INIT, NULL, NULL, 0, 0, 0, 0}
1163
1164 static int get_next_submodule(struct child_process *cp,
1165                               struct strbuf *err, void *data, void **task_cb)
1166 {
1167         int ret = 0;
1168         struct submodule_parallel_fetch *spf = data;
1169
1170         for (; spf->count < active_nr; spf->count++) {
1171                 struct strbuf submodule_path = STRBUF_INIT;
1172                 struct strbuf submodule_git_dir = STRBUF_INIT;
1173                 struct strbuf submodule_prefix = STRBUF_INIT;
1174                 const struct cache_entry *ce = active_cache[spf->count];
1175                 const char *git_dir, *default_argv;
1176                 const struct submodule *submodule;
1177
1178                 if (!S_ISGITLINK(ce->ce_mode))
1179                         continue;
1180
1181                 submodule = submodule_from_path(&null_oid, ce->name);
1182                 if (!submodule)
1183                         submodule = submodule_from_name(&null_oid, ce->name);
1184
1185                 default_argv = "yes";
1186                 if (spf->command_line_option == RECURSE_SUBMODULES_DEFAULT) {
1187                         if (submodule &&
1188                             submodule->fetch_recurse !=
1189                                                 RECURSE_SUBMODULES_NONE) {
1190                                 if (submodule->fetch_recurse ==
1191                                                 RECURSE_SUBMODULES_OFF)
1192                                         continue;
1193                                 if (submodule->fetch_recurse ==
1194                                                 RECURSE_SUBMODULES_ON_DEMAND) {
1195                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
1196                                                 continue;
1197                                         default_argv = "on-demand";
1198                                 }
1199                         } else {
1200                                 if (spf->default_option == RECURSE_SUBMODULES_OFF)
1201                                         continue;
1202                                 if (spf->default_option == RECURSE_SUBMODULES_ON_DEMAND) {
1203                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
1204                                                 continue;
1205                                         default_argv = "on-demand";
1206                                 }
1207                         }
1208                 } else if (spf->command_line_option == RECURSE_SUBMODULES_ON_DEMAND) {
1209                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
1210                                 continue;
1211                         default_argv = "on-demand";
1212                 }
1213
1214                 strbuf_addf(&submodule_path, "%s/%s", spf->work_tree, ce->name);
1215                 strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
1216                 strbuf_addf(&submodule_prefix, "%s%s/", spf->prefix, ce->name);
1217                 git_dir = read_gitfile(submodule_git_dir.buf);
1218                 if (!git_dir)
1219                         git_dir = submodule_git_dir.buf;
1220                 if (is_directory(git_dir)) {
1221                         child_process_init(cp);
1222                         cp->dir = strbuf_detach(&submodule_path, NULL);
1223                         prepare_submodule_repo_env(&cp->env_array);
1224                         cp->git_cmd = 1;
1225                         if (!spf->quiet)
1226                                 strbuf_addf(err, "Fetching submodule %s%s\n",
1227                                             spf->prefix, ce->name);
1228                         argv_array_init(&cp->args);
1229                         argv_array_pushv(&cp->args, spf->args.argv);
1230                         argv_array_push(&cp->args, default_argv);
1231                         argv_array_push(&cp->args, "--submodule-prefix");
1232                         argv_array_push(&cp->args, submodule_prefix.buf);
1233                         ret = 1;
1234                 }
1235                 strbuf_release(&submodule_path);
1236                 strbuf_release(&submodule_git_dir);
1237                 strbuf_release(&submodule_prefix);
1238                 if (ret) {
1239                         spf->count++;
1240                         return 1;
1241                 }
1242         }
1243         return 0;
1244 }
1245
1246 static int fetch_start_failure(struct strbuf *err,
1247                                void *cb, void *task_cb)
1248 {
1249         struct submodule_parallel_fetch *spf = cb;
1250
1251         spf->result = 1;
1252
1253         return 0;
1254 }
1255
1256 static int fetch_finish(int retvalue, struct strbuf *err,
1257                         void *cb, void *task_cb)
1258 {
1259         struct submodule_parallel_fetch *spf = cb;
1260
1261         if (retvalue)
1262                 spf->result = 1;
1263
1264         return 0;
1265 }
1266
1267 int fetch_populated_submodules(const struct argv_array *options,
1268                                const char *prefix, int command_line_option,
1269                                int default_option,
1270                                int quiet, int max_parallel_jobs)
1271 {
1272         int i;
1273         struct submodule_parallel_fetch spf = SPF_INIT;
1274
1275         spf.work_tree = get_git_work_tree();
1276         spf.command_line_option = command_line_option;
1277         spf.default_option = default_option;
1278         spf.quiet = quiet;
1279         spf.prefix = prefix;
1280
1281         if (!spf.work_tree)
1282                 goto out;
1283
1284         if (read_cache() < 0)
1285                 die("index file corrupt");
1286
1287         argv_array_push(&spf.args, "fetch");
1288         for (i = 0; i < options->argc; i++)
1289                 argv_array_push(&spf.args, options->argv[i]);
1290         argv_array_push(&spf.args, "--recurse-submodules-default");
1291         /* default value, "--submodule-prefix" and its value are added later */
1292
1293         calculate_changed_submodule_paths();
1294         run_processes_parallel(max_parallel_jobs,
1295                                get_next_submodule,
1296                                fetch_start_failure,
1297                                fetch_finish,
1298                                &spf);
1299
1300         argv_array_clear(&spf.args);
1301 out:
1302         string_list_clear(&changed_submodule_paths, 1);
1303         return spf.result;
1304 }
1305
1306 unsigned is_submodule_modified(const char *path, int ignore_untracked)
1307 {
1308         struct child_process cp = CHILD_PROCESS_INIT;
1309         struct strbuf buf = STRBUF_INIT;
1310         FILE *fp;
1311         unsigned dirty_submodule = 0;
1312         const char *git_dir;
1313         int ignore_cp_exit_code = 0;
1314
1315         strbuf_addf(&buf, "%s/.git", path);
1316         git_dir = read_gitfile(buf.buf);
1317         if (!git_dir)
1318                 git_dir = buf.buf;
1319         if (!is_git_directory(git_dir)) {
1320                 if (is_directory(git_dir))
1321                         die(_("'%s' not recognized as a git repository"), git_dir);
1322                 strbuf_release(&buf);
1323                 /* The submodule is not checked out, so it is not modified */
1324                 return 0;
1325         }
1326         strbuf_reset(&buf);
1327
1328         argv_array_pushl(&cp.args, "status", "--porcelain=2", NULL);
1329         if (ignore_untracked)
1330                 argv_array_push(&cp.args, "-uno");
1331
1332         prepare_submodule_repo_env(&cp.env_array);
1333         cp.git_cmd = 1;
1334         cp.no_stdin = 1;
1335         cp.out = -1;
1336         cp.dir = path;
1337         if (start_command(&cp))
1338                 die("Could not run 'git status --porcelain=2' in submodule %s", path);
1339
1340         fp = xfdopen(cp.out, "r");
1341         while (strbuf_getwholeline(&buf, fp, '\n') != EOF) {
1342                 /* regular untracked files */
1343                 if (buf.buf[0] == '?')
1344                         dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
1345
1346                 if (buf.buf[0] == 'u' ||
1347                     buf.buf[0] == '1' ||
1348                     buf.buf[0] == '2') {
1349                         /* T = line type, XY = status, SSSS = submodule state */
1350                         if (buf.len < strlen("T XY SSSS"))
1351                                 die("BUG: invalid status --porcelain=2 line %s",
1352                                     buf.buf);
1353
1354                         if (buf.buf[5] == 'S' && buf.buf[8] == 'U')
1355                                 /* nested untracked file */
1356                                 dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
1357
1358                         if (buf.buf[0] == 'u' ||
1359                             buf.buf[0] == '2' ||
1360                             memcmp(buf.buf + 5, "S..U", 4))
1361                                 /* other change */
1362                                 dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
1363                 }
1364
1365                 if ((dirty_submodule & DIRTY_SUBMODULE_MODIFIED) &&
1366                     ((dirty_submodule & DIRTY_SUBMODULE_UNTRACKED) ||
1367                      ignore_untracked)) {
1368                         /*
1369                          * We're not interested in any further information from
1370                          * the child any more, neither output nor its exit code.
1371                          */
1372                         ignore_cp_exit_code = 1;
1373                         break;
1374                 }
1375         }
1376         fclose(fp);
1377
1378         if (finish_command(&cp) && !ignore_cp_exit_code)
1379                 die("'git status --porcelain=2' failed in submodule %s", path);
1380
1381         strbuf_release(&buf);
1382         return dirty_submodule;
1383 }
1384
1385 int submodule_uses_gitfile(const char *path)
1386 {
1387         struct child_process cp = CHILD_PROCESS_INIT;
1388         const char *argv[] = {
1389                 "submodule",
1390                 "foreach",
1391                 "--quiet",
1392                 "--recursive",
1393                 "test -f .git",
1394                 NULL,
1395         };
1396         struct strbuf buf = STRBUF_INIT;
1397         const char *git_dir;
1398
1399         strbuf_addf(&buf, "%s/.git", path);
1400         git_dir = read_gitfile(buf.buf);
1401         if (!git_dir) {
1402                 strbuf_release(&buf);
1403                 return 0;
1404         }
1405         strbuf_release(&buf);
1406
1407         /* Now test that all nested submodules use a gitfile too */
1408         cp.argv = argv;
1409         prepare_submodule_repo_env(&cp.env_array);
1410         cp.git_cmd = 1;
1411         cp.no_stdin = 1;
1412         cp.no_stderr = 1;
1413         cp.no_stdout = 1;
1414         cp.dir = path;
1415         if (run_command(&cp))
1416                 return 0;
1417
1418         return 1;
1419 }
1420
1421 /*
1422  * Check if it is a bad idea to remove a submodule, i.e. if we'd lose data
1423  * when doing so.
1424  *
1425  * Return 1 if we'd lose data, return 0 if the removal is fine,
1426  * and negative values for errors.
1427  */
1428 int bad_to_remove_submodule(const char *path, unsigned flags)
1429 {
1430         ssize_t len;
1431         struct child_process cp = CHILD_PROCESS_INIT;
1432         struct strbuf buf = STRBUF_INIT;
1433         int ret = 0;
1434
1435         if (!file_exists(path) || is_empty_dir(path))
1436                 return 0;
1437
1438         if (!submodule_uses_gitfile(path))
1439                 return 1;
1440
1441         argv_array_pushl(&cp.args, "status", "--porcelain",
1442                                    "--ignore-submodules=none", NULL);
1443
1444         if (flags & SUBMODULE_REMOVAL_IGNORE_UNTRACKED)
1445                 argv_array_push(&cp.args, "-uno");
1446         else
1447                 argv_array_push(&cp.args, "-uall");
1448
1449         if (!(flags & SUBMODULE_REMOVAL_IGNORE_IGNORED_UNTRACKED))
1450                 argv_array_push(&cp.args, "--ignored");
1451
1452         prepare_submodule_repo_env(&cp.env_array);
1453         cp.git_cmd = 1;
1454         cp.no_stdin = 1;
1455         cp.out = -1;
1456         cp.dir = path;
1457         if (start_command(&cp)) {
1458                 if (flags & SUBMODULE_REMOVAL_DIE_ON_ERROR)
1459                         die(_("could not start 'git status' in submodule '%s'"),
1460                                 path);
1461                 ret = -1;
1462                 goto out;
1463         }
1464
1465         len = strbuf_read(&buf, cp.out, 1024);
1466         if (len > 2)
1467                 ret = 1;
1468         close(cp.out);
1469
1470         if (finish_command(&cp)) {
1471                 if (flags & SUBMODULE_REMOVAL_DIE_ON_ERROR)
1472                         die(_("could not run 'git status' in submodule '%s'"),
1473                                 path);
1474                 ret = -1;
1475         }
1476 out:
1477         strbuf_release(&buf);
1478         return ret;
1479 }
1480
1481 static const char *get_super_prefix_or_empty(void)
1482 {
1483         const char *s = get_super_prefix();
1484         if (!s)
1485                 s = "";
1486         return s;
1487 }
1488
1489 static int submodule_has_dirty_index(const struct submodule *sub)
1490 {
1491         struct child_process cp = CHILD_PROCESS_INIT;
1492
1493         prepare_submodule_repo_env(&cp.env_array);
1494
1495         cp.git_cmd = 1;
1496         argv_array_pushl(&cp.args, "diff-index", "--quiet",
1497                                    "--cached", "HEAD", NULL);
1498         cp.no_stdin = 1;
1499         cp.no_stdout = 1;
1500         cp.dir = sub->path;
1501         if (start_command(&cp))
1502                 die("could not recurse into submodule '%s'", sub->path);
1503
1504         return finish_command(&cp);
1505 }
1506
1507 static void submodule_reset_index(const char *path)
1508 {
1509         struct child_process cp = CHILD_PROCESS_INIT;
1510         prepare_submodule_repo_env(&cp.env_array);
1511
1512         cp.git_cmd = 1;
1513         cp.no_stdin = 1;
1514         cp.dir = path;
1515
1516         argv_array_pushf(&cp.args, "--super-prefix=%s%s/",
1517                                    get_super_prefix_or_empty(), path);
1518         argv_array_pushl(&cp.args, "read-tree", "-u", "--reset", NULL);
1519
1520         argv_array_push(&cp.args, EMPTY_TREE_SHA1_HEX);
1521
1522         if (run_command(&cp))
1523                 die("could not reset submodule index");
1524 }
1525
1526 /**
1527  * Moves a submodule at a given path from a given head to another new head.
1528  * For edge cases (a submodule coming into existence or removing a submodule)
1529  * pass NULL for old or new respectively.
1530  */
1531 int submodule_move_head(const char *path,
1532                          const char *old,
1533                          const char *new,
1534                          unsigned flags)
1535 {
1536         int ret = 0;
1537         struct child_process cp = CHILD_PROCESS_INIT;
1538         const struct submodule *sub;
1539         int *error_code_ptr, error_code;
1540
1541         if (!is_submodule_active(the_repository, path))
1542                 return 0;
1543
1544         if (flags & SUBMODULE_MOVE_HEAD_FORCE)
1545                 /*
1546                  * Pass non NULL pointer to is_submodule_populated_gently
1547                  * to prevent die()-ing. We'll use connect_work_tree_and_git_dir
1548                  * to fixup the submodule in the force case later.
1549                  */
1550                 error_code_ptr = &error_code;
1551         else
1552                 error_code_ptr = NULL;
1553
1554         if (old && !is_submodule_populated_gently(path, error_code_ptr))
1555                 return 0;
1556
1557         sub = submodule_from_path(&null_oid, path);
1558
1559         if (!sub)
1560                 die("BUG: could not get submodule information for '%s'", path);
1561
1562         if (old && !(flags & SUBMODULE_MOVE_HEAD_FORCE)) {
1563                 /* Check if the submodule has a dirty index. */
1564                 if (submodule_has_dirty_index(sub))
1565                         return error(_("submodule '%s' has dirty index"), path);
1566         }
1567
1568         if (!(flags & SUBMODULE_MOVE_HEAD_DRY_RUN)) {
1569                 if (old) {
1570                         if (!submodule_uses_gitfile(path))
1571                                 absorb_git_dir_into_superproject("", path,
1572                                         ABSORB_GITDIR_RECURSE_SUBMODULES);
1573                 } else {
1574                         char *gitdir = xstrfmt("%s/modules/%s",
1575                                     get_git_common_dir(), sub->name);
1576                         connect_work_tree_and_git_dir(path, gitdir);
1577                         free(gitdir);
1578
1579                         /* make sure the index is clean as well */
1580                         submodule_reset_index(path);
1581                 }
1582
1583                 if (old && (flags & SUBMODULE_MOVE_HEAD_FORCE)) {
1584                         char *gitdir = xstrfmt("%s/modules/%s",
1585                                     get_git_common_dir(), sub->name);
1586                         connect_work_tree_and_git_dir(path, gitdir);
1587                         free(gitdir);
1588                 }
1589         }
1590
1591         prepare_submodule_repo_env(&cp.env_array);
1592
1593         cp.git_cmd = 1;
1594         cp.no_stdin = 1;
1595         cp.dir = path;
1596
1597         argv_array_pushf(&cp.args, "--super-prefix=%s%s/",
1598                         get_super_prefix_or_empty(), path);
1599         argv_array_pushl(&cp.args, "read-tree", "--recurse-submodules", NULL);
1600
1601         if (flags & SUBMODULE_MOVE_HEAD_DRY_RUN)
1602                 argv_array_push(&cp.args, "-n");
1603         else
1604                 argv_array_push(&cp.args, "-u");
1605
1606         if (flags & SUBMODULE_MOVE_HEAD_FORCE)
1607                 argv_array_push(&cp.args, "--reset");
1608         else
1609                 argv_array_push(&cp.args, "-m");
1610
1611         argv_array_push(&cp.args, old ? old : EMPTY_TREE_SHA1_HEX);
1612         argv_array_push(&cp.args, new ? new : EMPTY_TREE_SHA1_HEX);
1613
1614         if (run_command(&cp)) {
1615                 ret = -1;
1616                 goto out;
1617         }
1618
1619         if (!(flags & SUBMODULE_MOVE_HEAD_DRY_RUN)) {
1620                 if (new) {
1621                         child_process_init(&cp);
1622                         /* also set the HEAD accordingly */
1623                         cp.git_cmd = 1;
1624                         cp.no_stdin = 1;
1625                         cp.dir = path;
1626
1627                         prepare_submodule_repo_env(&cp.env_array);
1628                         argv_array_pushl(&cp.args, "update-ref", "HEAD", new, NULL);
1629
1630                         if (run_command(&cp)) {
1631                                 ret = -1;
1632                                 goto out;
1633                         }
1634                 } else {
1635                         struct strbuf sb = STRBUF_INIT;
1636
1637                         strbuf_addf(&sb, "%s/.git", path);
1638                         unlink_or_warn(sb.buf);
1639                         strbuf_release(&sb);
1640
1641                         if (is_empty_dir(path))
1642                                 rmdir_or_warn(path);
1643                 }
1644         }
1645 out:
1646         return ret;
1647 }
1648
1649 static int find_first_merges(struct object_array *result, const char *path,
1650                 struct commit *a, struct commit *b)
1651 {
1652         int i, j;
1653         struct object_array merges = OBJECT_ARRAY_INIT;
1654         struct commit *commit;
1655         int contains_another;
1656
1657         char merged_revision[42];
1658         const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
1659                                    "--all", merged_revision, NULL };
1660         struct rev_info revs;
1661         struct setup_revision_opt rev_opts;
1662
1663         memset(result, 0, sizeof(struct object_array));
1664         memset(&rev_opts, 0, sizeof(rev_opts));
1665
1666         /* get all revisions that merge commit a */
1667         xsnprintf(merged_revision, sizeof(merged_revision), "^%s",
1668                         oid_to_hex(&a->object.oid));
1669         init_revisions(&revs, NULL);
1670         rev_opts.submodule = path;
1671         setup_revisions(ARRAY_SIZE(rev_args)-1, rev_args, &revs, &rev_opts);
1672
1673         /* save all revisions from the above list that contain b */
1674         if (prepare_revision_walk(&revs))
1675                 die("revision walk setup failed");
1676         while ((commit = get_revision(&revs)) != NULL) {
1677                 struct object *o = &(commit->object);
1678                 if (in_merge_bases(b, commit))
1679                         add_object_array(o, NULL, &merges);
1680         }
1681         reset_revision_walk();
1682
1683         /* Now we've got all merges that contain a and b. Prune all
1684          * merges that contain another found merge and save them in
1685          * result.
1686          */
1687         for (i = 0; i < merges.nr; i++) {
1688                 struct commit *m1 = (struct commit *) merges.objects[i].item;
1689
1690                 contains_another = 0;
1691                 for (j = 0; j < merges.nr; j++) {
1692                         struct commit *m2 = (struct commit *) merges.objects[j].item;
1693                         if (i != j && in_merge_bases(m2, m1)) {
1694                                 contains_another = 1;
1695                                 break;
1696                         }
1697                 }
1698
1699                 if (!contains_another)
1700                         add_object_array(merges.objects[i].item, NULL, result);
1701         }
1702
1703         free(merges.objects);
1704         return result->nr;
1705 }
1706
1707 static void print_commit(struct commit *commit)
1708 {
1709         struct strbuf sb = STRBUF_INIT;
1710         struct pretty_print_context ctx = {0};
1711         ctx.date_mode.type = DATE_NORMAL;
1712         format_commit_message(commit, " %h: %m %s", &sb, &ctx);
1713         fprintf(stderr, "%s\n", sb.buf);
1714         strbuf_release(&sb);
1715 }
1716
1717 #define MERGE_WARNING(path, msg) \
1718         warning("Failed to merge submodule %s (%s)", path, msg);
1719
1720 int merge_submodule(struct object_id *result, const char *path,
1721                     const struct object_id *base, const struct object_id *a,
1722                     const struct object_id *b, int search)
1723 {
1724         struct commit *commit_base, *commit_a, *commit_b;
1725         int parent_count;
1726         struct object_array merges;
1727
1728         int i;
1729
1730         /* store a in result in case we fail */
1731         oidcpy(result, a);
1732
1733         /* we can not handle deletion conflicts */
1734         if (is_null_oid(base))
1735                 return 0;
1736         if (is_null_oid(a))
1737                 return 0;
1738         if (is_null_oid(b))
1739                 return 0;
1740
1741         if (add_submodule_odb(path)) {
1742                 MERGE_WARNING(path, "not checked out");
1743                 return 0;
1744         }
1745
1746         if (!(commit_base = lookup_commit_reference(base)) ||
1747             !(commit_a = lookup_commit_reference(a)) ||
1748             !(commit_b = lookup_commit_reference(b))) {
1749                 MERGE_WARNING(path, "commits not present");
1750                 return 0;
1751         }
1752
1753         /* check whether both changes are forward */
1754         if (!in_merge_bases(commit_base, commit_a) ||
1755             !in_merge_bases(commit_base, commit_b)) {
1756                 MERGE_WARNING(path, "commits don't follow merge-base");
1757                 return 0;
1758         }
1759
1760         /* Case #1: a is contained in b or vice versa */
1761         if (in_merge_bases(commit_a, commit_b)) {
1762                 oidcpy(result, b);
1763                 return 1;
1764         }
1765         if (in_merge_bases(commit_b, commit_a)) {
1766                 oidcpy(result, a);
1767                 return 1;
1768         }
1769
1770         /*
1771          * Case #2: There are one or more merges that contain a and b in
1772          * the submodule. If there is only one, then present it as a
1773          * suggestion to the user, but leave it marked unmerged so the
1774          * user needs to confirm the resolution.
1775          */
1776
1777         /* Skip the search if makes no sense to the calling context.  */
1778         if (!search)
1779                 return 0;
1780
1781         /* find commit which merges them */
1782         parent_count = find_first_merges(&merges, path, commit_a, commit_b);
1783         switch (parent_count) {
1784         case 0:
1785                 MERGE_WARNING(path, "merge following commits not found");
1786                 break;
1787
1788         case 1:
1789                 MERGE_WARNING(path, "not fast-forward");
1790                 fprintf(stderr, "Found a possible merge resolution "
1791                                 "for the submodule:\n");
1792                 print_commit((struct commit *) merges.objects[0].item);
1793                 fprintf(stderr,
1794                         "If this is correct simply add it to the index "
1795                         "for example\n"
1796                         "by using:\n\n"
1797                         "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1798                         "which will accept this suggestion.\n",
1799                         oid_to_hex(&merges.objects[0].item->oid), path);
1800                 break;
1801
1802         default:
1803                 MERGE_WARNING(path, "multiple merges found");
1804                 for (i = 0; i < merges.nr; i++)
1805                         print_commit((struct commit *) merges.objects[i].item);
1806         }
1807
1808         free(merges.objects);
1809         return 0;
1810 }
1811
1812 /*
1813  * Embeds a single submodules git directory into the superprojects git dir,
1814  * non recursively.
1815  */
1816 static void relocate_single_git_dir_into_superproject(const char *prefix,
1817                                                       const char *path)
1818 {
1819         char *old_git_dir = NULL, *real_old_git_dir = NULL, *real_new_git_dir = NULL;
1820         const char *new_git_dir;
1821         const struct submodule *sub;
1822
1823         if (submodule_uses_worktrees(path))
1824                 die(_("relocate_gitdir for submodule '%s' with "
1825                       "more than one worktree not supported"), path);
1826
1827         old_git_dir = xstrfmt("%s/.git", path);
1828         if (read_gitfile(old_git_dir))
1829                 /* If it is an actual gitfile, it doesn't need migration. */
1830                 return;
1831
1832         real_old_git_dir = real_pathdup(old_git_dir, 1);
1833
1834         sub = submodule_from_path(&null_oid, path);
1835         if (!sub)
1836                 die(_("could not lookup name for submodule '%s'"), path);
1837
1838         new_git_dir = git_path("modules/%s", sub->name);
1839         if (safe_create_leading_directories_const(new_git_dir) < 0)
1840                 die(_("could not create directory '%s'"), new_git_dir);
1841         real_new_git_dir = real_pathdup(new_git_dir, 1);
1842
1843         fprintf(stderr, _("Migrating git directory of '%s%s' from\n'%s' to\n'%s'\n"),
1844                 get_super_prefix_or_empty(), path,
1845                 real_old_git_dir, real_new_git_dir);
1846
1847         relocate_gitdir(path, real_old_git_dir, real_new_git_dir);
1848
1849         free(old_git_dir);
1850         free(real_old_git_dir);
1851         free(real_new_git_dir);
1852 }
1853
1854 /*
1855  * Migrate the git directory of the submodule given by path from
1856  * having its git directory within the working tree to the git dir nested
1857  * in its superprojects git dir under modules/.
1858  */
1859 void absorb_git_dir_into_superproject(const char *prefix,
1860                                       const char *path,
1861                                       unsigned flags)
1862 {
1863         int err_code;
1864         const char *sub_git_dir;
1865         struct strbuf gitdir = STRBUF_INIT;
1866         strbuf_addf(&gitdir, "%s/.git", path);
1867         sub_git_dir = resolve_gitdir_gently(gitdir.buf, &err_code);
1868
1869         /* Not populated? */
1870         if (!sub_git_dir) {
1871                 const struct submodule *sub;
1872
1873                 if (err_code == READ_GITFILE_ERR_STAT_FAILED) {
1874                         /* unpopulated as expected */
1875                         strbuf_release(&gitdir);
1876                         return;
1877                 }
1878
1879                 if (err_code != READ_GITFILE_ERR_NOT_A_REPO)
1880                         /* We don't know what broke here. */
1881                         read_gitfile_error_die(err_code, path, NULL);
1882
1883                 /*
1884                 * Maybe populated, but no git directory was found?
1885                 * This can happen if the superproject is a submodule
1886                 * itself and was just absorbed. The absorption of the
1887                 * superproject did not rewrite the git file links yet,
1888                 * fix it now.
1889                 */
1890                 sub = submodule_from_path(&null_oid, path);
1891                 if (!sub)
1892                         die(_("could not lookup name for submodule '%s'"), path);
1893                 connect_work_tree_and_git_dir(path,
1894                         git_path("modules/%s", sub->name));
1895         } else {
1896                 /* Is it already absorbed into the superprojects git dir? */
1897                 char *real_sub_git_dir = real_pathdup(sub_git_dir, 1);
1898                 char *real_common_git_dir = real_pathdup(get_git_common_dir(), 1);
1899
1900                 if (!starts_with(real_sub_git_dir, real_common_git_dir))
1901                         relocate_single_git_dir_into_superproject(prefix, path);
1902
1903                 free(real_sub_git_dir);
1904                 free(real_common_git_dir);
1905         }
1906         strbuf_release(&gitdir);
1907
1908         if (flags & ABSORB_GITDIR_RECURSE_SUBMODULES) {
1909                 struct child_process cp = CHILD_PROCESS_INIT;
1910                 struct strbuf sb = STRBUF_INIT;
1911
1912                 if (flags & ~ABSORB_GITDIR_RECURSE_SUBMODULES)
1913                         die("BUG: we don't know how to pass the flags down?");
1914
1915                 strbuf_addstr(&sb, get_super_prefix_or_empty());
1916                 strbuf_addstr(&sb, path);
1917                 strbuf_addch(&sb, '/');
1918
1919                 cp.dir = path;
1920                 cp.git_cmd = 1;
1921                 cp.no_stdin = 1;
1922                 argv_array_pushl(&cp.args, "--super-prefix", sb.buf,
1923                                            "submodule--helper",
1924                                            "absorb-git-dirs", NULL);
1925                 prepare_submodule_repo_env(&cp.env_array);
1926                 if (run_command(&cp))
1927                         die(_("could not recurse into submodule '%s'"), path);
1928
1929                 strbuf_release(&sb);
1930         }
1931 }
1932
1933 const char *get_superproject_working_tree(void)
1934 {
1935         struct child_process cp = CHILD_PROCESS_INIT;
1936         struct strbuf sb = STRBUF_INIT;
1937         const char *one_up = real_path_if_valid("../");
1938         const char *cwd = xgetcwd();
1939         const char *ret = NULL;
1940         const char *subpath;
1941         int code;
1942         ssize_t len;
1943
1944         if (!is_inside_work_tree())
1945                 /*
1946                  * FIXME:
1947                  * We might have a superproject, but it is harder
1948                  * to determine.
1949                  */
1950                 return NULL;
1951
1952         if (!one_up)
1953                 return NULL;
1954
1955         subpath = relative_path(cwd, one_up, &sb);
1956
1957         prepare_submodule_repo_env(&cp.env_array);
1958         argv_array_pop(&cp.env_array);
1959
1960         argv_array_pushl(&cp.args, "--literal-pathspecs", "-C", "..",
1961                         "ls-files", "-z", "--stage", "--full-name", "--",
1962                         subpath, NULL);
1963         strbuf_reset(&sb);
1964
1965         cp.no_stdin = 1;
1966         cp.no_stderr = 1;
1967         cp.out = -1;
1968         cp.git_cmd = 1;
1969
1970         if (start_command(&cp))
1971                 die(_("could not start ls-files in .."));
1972
1973         len = strbuf_read(&sb, cp.out, PATH_MAX);
1974         close(cp.out);
1975
1976         if (starts_with(sb.buf, "160000")) {
1977                 int super_sub_len;
1978                 int cwd_len = strlen(cwd);
1979                 char *super_sub, *super_wt;
1980
1981                 /*
1982                  * There is a superproject having this repo as a submodule.
1983                  * The format is <mode> SP <hash> SP <stage> TAB <full name> \0,
1984                  * We're only interested in the name after the tab.
1985                  */
1986                 super_sub = strchr(sb.buf, '\t') + 1;
1987                 super_sub_len = sb.buf + sb.len - super_sub - 1;
1988
1989                 if (super_sub_len > cwd_len ||
1990                     strcmp(&cwd[cwd_len - super_sub_len], super_sub))
1991                         die (_("BUG: returned path string doesn't match cwd?"));
1992
1993                 super_wt = xstrdup(cwd);
1994                 super_wt[cwd_len - super_sub_len] = '\0';
1995
1996                 ret = real_path(super_wt);
1997                 free(super_wt);
1998         }
1999         strbuf_release(&sb);
2000
2001         code = finish_command(&cp);
2002
2003         if (code == 128)
2004                 /* '../' is not a git repository */
2005                 return NULL;
2006         if (code == 0 && len == 0)
2007                 /* There is an unrelated git repository at '../' */
2008                 return NULL;
2009         if (code)
2010                 die(_("ls-tree returned unexpected return code %d"), code);
2011
2012         return ret;
2013 }
2014
2015 int submodule_to_gitdir(struct strbuf *buf, const char *submodule)
2016 {
2017         const struct submodule *sub;
2018         const char *git_dir;
2019         int ret = 0;
2020
2021         strbuf_reset(buf);
2022         strbuf_addstr(buf, submodule);
2023         strbuf_complete(buf, '/');
2024         strbuf_addstr(buf, ".git");
2025
2026         git_dir = read_gitfile(buf->buf);
2027         if (git_dir) {
2028                 strbuf_reset(buf);
2029                 strbuf_addstr(buf, git_dir);
2030         }
2031         if (!is_git_directory(buf->buf)) {
2032                 gitmodules_config();
2033                 sub = submodule_from_path(&null_oid, submodule);
2034                 if (!sub) {
2035                         ret = -1;
2036                         goto cleanup;
2037                 }
2038                 strbuf_reset(buf);
2039                 strbuf_git_path(buf, "%s/%s", "modules", sub->name);
2040         }
2041
2042 cleanup:
2043         return ret;
2044 }