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_names = 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, CE_MATCH_IGNORE_FSMONITOR) & DATA_CHANGED)
  66                         return 0;
  67         }
  68
  69         return 1;
  70 }
  71
  72 static int for_each_remote_ref_submodule(const char *submodule,
  73                                          each_ref_fn fn, void *cb_data)
  74 {
  75         return refs_for_each_remote_ref(get_submodule_ref_store(submodule),
  76                                         fn, cb_data);
  77 }
  78
  79 /*
  80  * Try to update the "path" entry in the "submodule.<name>" section of the
  81  * .gitmodules file. Return 0 only if a .gitmodules file was found, a section
  82  * with the correct path=<oldpath> setting was found and we could update it.
  83  */
  84 int update_path_in_gitmodules(const char *oldpath, const char *newpath)
  85 {
  86         struct strbuf entry = STRBUF_INIT;
  87         const struct submodule *submodule;
  88
  89         if (!file_exists(GITMODULES_FILE)) /* Do nothing without .gitmodules */
  90                 return -1;
  91
  92         if (is_gitmodules_unmerged(&the_index))
  93                 die(_("Cannot change unmerged .gitmodules, resolve merge conflicts first"));
  94
  95         submodule = submodule_from_path(&null_oid, oldpath);
  96         if (!submodule || !submodule->name) {
  97                 warning(_("Could not find section in .gitmodules where path=%s"), oldpath);
  98                 return -1;
  99         }
 100         strbuf_addstr(&entry, "submodule.");
 101         strbuf_addstr(&entry, submodule->name);
 102         strbuf_addstr(&entry, ".path");
 103         if (git_config_set_in_file_gently(GITMODULES_FILE, entry.buf, newpath) < 0) {
 104                 /* Maybe the user already did that, don't error out here */
 105                 warning(_("Could not update .gitmodules entry %s"), entry.buf);
 106                 strbuf_release(&entry);
 107                 return -1;
 108         }
 109         strbuf_release(&entry);
 110         return 0;
 111 }
 112
 113 /*
 114  * Try to remove the "submodule.<name>" section from .gitmodules where the given
 115  * path is configured. Return 0 only if a .gitmodules file was found, a section
 116  * with the correct path=<path> setting was found and we could remove it.
 117  */
 118 int remove_path_from_gitmodules(const char *path)
 119 {
 120         struct strbuf sect = STRBUF_INIT;
 121         const struct submodule *submodule;
 122
 123         if (!file_exists(GITMODULES_FILE)) /* Do nothing without .gitmodules */
 124                 return -1;
 125
 126         if (is_gitmodules_unmerged(&the_index))
 127                 die(_("Cannot change unmerged .gitmodules, resolve merge conflicts first"));
 128
 129         submodule = submodule_from_path(&null_oid, path);
 130         if (!submodule || !submodule->name) {
 131                 warning(_("Could not find section in .gitmodules where path=%s"), path);
 132                 return -1;
 133         }
 134         strbuf_addstr(&sect, "submodule.");
 135         strbuf_addstr(&sect, submodule->name);
 136         if (git_config_rename_section_in_file(GITMODULES_FILE, sect.buf, NULL) < 0) {
 137                 /* Maybe the user already did that, don't error out here */
 138                 warning(_("Could not remove .gitmodules entry for %s"), path);
 139                 strbuf_release(&sect);
 140                 return -1;
 141         }
 142         strbuf_release(&sect);
 143         return 0;
 144 }
 145
 146 void stage_updated_gitmodules(void)
 147 {
 148         if (add_file_to_cache(GITMODULES_FILE, 0))
 149                 die(_("staging updated .gitmodules failed"));
 150 }
 151
 152 static int add_submodule_odb(const char *path)
 153 {
 154         struct strbuf objects_directory = STRBUF_INIT;
 155         int ret = 0;
 156
 157         ret = strbuf_git_path_submodule(&objects_directory, path, "objects/");
 158         if (ret)
 159                 goto done;
 160         if (!is_directory(objects_directory.buf)) {
 161                 ret = -1;
 162                 goto done;
 163         }
 164         add_to_alternates_memory(objects_directory.buf);
 165 done:
 166         strbuf_release(&objects_directory);
 167         return ret;
 168 }
 169
 170 void set_diffopt_flags_from_submodule_config(struct diff_options *diffopt,
 171                                              const char *path)
 172 {
 173         const struct submodule *submodule = submodule_from_path(&null_oid, path);
 174         if (submodule) {
 175                 const char *ignore;
 176                 char *key;
 177
 178                 key = xstrfmt("submodule.%s.ignore", submodule->name);
 179                 if (repo_config_get_string_const(the_repository, key, &ignore))
 180                         ignore = submodule->ignore;
 181                 free(key);
 182
 183                 if (ignore)
 184                         handle_ignore_submodules_arg(diffopt, ignore);
 185                 else if (is_gitmodules_unmerged(&the_index))
 186                         diffopt->flags.ignore_submodules = 1;
 187         }
 188 }
 189
 190 /* Cheap function that only determines if we're interested in submodules at all */
 191 int git_default_submodule_config(const char *var, const char *value, void *cb)
 192 {
 193         if (!strcmp(var, "submodule.recurse")) {
 194                 int v = git_config_bool(var, value) ?
 195                         RECURSE_SUBMODULES_ON : RECURSE_SUBMODULES_OFF;
 196                 config_update_recurse_submodules = v;
 197         }
 198         return 0;
 199 }
 200
 201 int option_parse_recurse_submodules_worktree_updater(const struct option *opt,
 202                                                      const char *arg, int unset)
 203 {
 204         if (unset) {
 205                 config_update_recurse_submodules = RECURSE_SUBMODULES_OFF;
 206                 return 0;
 207         }
 208         if (arg)
 209                 config_update_recurse_submodules =
 210                         parse_update_recurse_submodules_arg(opt->long_name,
 211                                                             arg);
 212         else
 213                 config_update_recurse_submodules = RECURSE_SUBMODULES_ON;
 214
 215         return 0;
 216 }
 217
 218 /*
 219  * Determine if a submodule has been initialized at a given 'path'
 220  */
 221 int is_submodule_active(struct repository *repo, const char *path)
 222 {
 223         int ret = 0;
 224         char *key = NULL;
 225         char *value = NULL;
 226         const struct string_list *sl;
 227         const struct submodule *module;
 228
 229         module = submodule_from_cache(repo, &null_oid, path);
 230
 231         /* early return if there isn't a path->module mapping */
 232         if (!module)
 233                 return 0;
 234
 235         /* submodule.<name>.active is set */
 236         key = xstrfmt("submodule.%s.active", module->name);
 237         if (!repo_config_get_bool(repo, key, &ret)) {
 238                 free(key);
 239                 return ret;
 240         }
 241         free(key);
 242
 243         /* submodule.active is set */
 244         sl = repo_config_get_value_multi(repo, "submodule.active");
 245         if (sl) {
 246                 struct pathspec ps;
 247                 struct argv_array args = ARGV_ARRAY_INIT;
 248                 const struct string_list_item *item;
 249
 250                 for_each_string_list_item(item, sl) {
 251                         argv_array_push(&args, item->string);
 252                 }
 253
 254                 parse_pathspec(&ps, 0, 0, NULL, args.argv);
 255                 ret = match_pathspec(&ps, path, strlen(path), 0, NULL, 1);
 256
 257                 argv_array_clear(&args);
 258                 clear_pathspec(&ps);
 259                 return ret;
 260         }
 261
 262         /* fallback to checking if the URL is set */
 263         key = xstrfmt("submodule.%s.url", module->name);
 264         ret = !repo_config_get_string(repo, key, &value);
 265
 266         free(value);
 267         free(key);
 268         return ret;
 269 }
 270
 271 int is_submodule_populated_gently(const char *path, int *return_error_code)
 272 {
 273         int ret = 0;
 274         char *gitdir = xstrfmt("%s/.git", path);
 275
 276         if (resolve_gitdir_gently(gitdir, return_error_code))
 277                 ret = 1;
 278
 279         free(gitdir);
 280         return ret;
 281 }
 282
 283 /*
 284  * Dies if the provided 'prefix' corresponds to an unpopulated submodule
 285  */
 286 void die_in_unpopulated_submodule(const struct index_state *istate,
 287                                   const char *prefix)
 288 {
 289         int i, prefixlen;
 290
 291         if (!prefix)
 292                 return;
 293
 294         prefixlen = strlen(prefix);
 295
 296         for (i = 0; i < istate->cache_nr; i++) {
 297                 struct cache_entry *ce = istate->cache[i];
 298                 int ce_len = ce_namelen(ce);
 299
 300                 if (!S_ISGITLINK(ce->ce_mode))
 301                         continue;
 302                 if (prefixlen <= ce_len)
 303                         continue;
 304                 if (strncmp(ce->name, prefix, ce_len))
 305                         continue;
 306                 if (prefix[ce_len] != '/')
 307                         continue;
 308
 309                 die(_("in unpopulated submodule '%s'"), ce->name);
 310         }
 311 }
 312
 313 /*
 314  * Dies if any paths in the provided pathspec descends into a submodule
 315  */
 316 void die_path_inside_submodule(const struct index_state *istate,
 317                                const struct pathspec *ps)
 318 {
 319         int i, j;
 320
 321         for (i = 0; i < istate->cache_nr; i++) {
 322                 struct cache_entry *ce = istate->cache[i];
 323                 int ce_len = ce_namelen(ce);
 324
 325                 if (!S_ISGITLINK(ce->ce_mode))
 326                         continue;
 327
 328                 for (j = 0; j < ps->nr ; j++) {
 329                         const struct pathspec_item *item = &ps->items[j];
 330
 331                         if (item->len <= ce_len)
 332                                 continue;
 333                         if (item->match[ce_len] != '/')
 334                                 continue;
 335                         if (strncmp(ce->name, item->match, ce_len))
 336                                 continue;
 337                         if (item->len == ce_len + 1)
 338                                 continue;
 339
 340                         die(_("Pathspec '%s' is in submodule '%.*s'"),
 341                             item->original, ce_len, ce->name);
 342                 }
 343         }
 344 }
 345
 346 enum submodule_update_type parse_submodule_update_type(const char *value)
 347 {
 348         if (!strcmp(value, "none"))
 349                 return SM_UPDATE_NONE;
 350         else if (!strcmp(value, "checkout"))
 351                 return SM_UPDATE_CHECKOUT;
 352         else if (!strcmp(value, "rebase"))
 353                 return SM_UPDATE_REBASE;
 354         else if (!strcmp(value, "merge"))
 355                 return SM_UPDATE_MERGE;
 356         else if (*value == '!')
 357                 return SM_UPDATE_COMMAND;
 358         else
 359                 return SM_UPDATE_UNSPECIFIED;
 360 }
 361
 362 int parse_submodule_update_strategy(const char *value,
 363                 struct submodule_update_strategy *dst)
 364 {
 365         enum submodule_update_type type;
 366
 367         free((void*)dst->command);
 368         dst->command = NULL;
 369
 370         type = parse_submodule_update_type(value);
 371         if (type == SM_UPDATE_UNSPECIFIED)
 372                 return -1;
 373
 374         dst->type = type;
 375         if (type == SM_UPDATE_COMMAND)
 376                 dst->command = xstrdup(value + 1);
 377
 378         return 0;
 379 }
 380
 381 const char *submodule_strategy_to_string(const struct submodule_update_strategy *s)
 382 {
 383         struct strbuf sb = STRBUF_INIT;
 384         switch (s->type) {
 385         case SM_UPDATE_CHECKOUT:
 386                 return "checkout";
 387         case SM_UPDATE_MERGE:
 388                 return "merge";
 389         case SM_UPDATE_REBASE:
 390                 return "rebase";
 391         case SM_UPDATE_NONE:
 392                 return "none";
 393         case SM_UPDATE_UNSPECIFIED:
 394                 return NULL;
 395         case SM_UPDATE_COMMAND:
 396                 strbuf_addf(&sb, "!%s", s->command);
 397                 return strbuf_detach(&sb, NULL);
 398         }
 399         return NULL;
 400 }
 401
 402 void handle_ignore_submodules_arg(struct diff_options *diffopt,
 403                                   const char *arg)
 404 {
 405         diffopt->flags.ignore_submodules = 0;
 406         diffopt->flags.ignore_untracked_in_submodules = 0;
 407         diffopt->flags.ignore_dirty_submodules = 0;
 408
 409         if (!strcmp(arg, "all"))
 410                 diffopt->flags.ignore_submodules = 1;
 411         else if (!strcmp(arg, "untracked"))
 412                 diffopt->flags.ignore_untracked_in_submodules = 1;
 413         else if (!strcmp(arg, "dirty"))
 414                 diffopt->flags.ignore_dirty_submodules = 1;
 415         else if (strcmp(arg, "none"))
 416                 die("bad --ignore-submodules argument: %s", arg);
 417 }
 418
 419 static int prepare_submodule_summary(struct rev_info *rev, const char *path,
 420                 struct commit *left, struct commit *right,
 421                 struct commit_list *merge_bases)
 422 {
 423         struct commit_list *list;
 424
 425         init_revisions(rev, NULL);
 426         setup_revisions(0, NULL, rev, NULL);
 427         rev->left_right = 1;
 428         rev->first_parent_only = 1;
 429         left->object.flags |= SYMMETRIC_LEFT;
 430         add_pending_object(rev, &left->object, path);
 431         add_pending_object(rev, &right->object, path);
 432         for (list = merge_bases; list; list = list->next) {
 433                 list->item->object.flags |= UNINTERESTING;
 434                 add_pending_object(rev, &list->item->object,
 435                         oid_to_hex(&list->item->object.oid));
 436         }
 437         return prepare_revision_walk(rev);
 438 }
 439
 440 static void print_submodule_summary(struct rev_info *rev, struct diff_options *o)
 441 {
 442         static const char format[] = "  %m %s";
 443         struct strbuf sb = STRBUF_INIT;
 444         struct commit *commit;
 445
 446         while ((commit = get_revision(rev))) {
 447                 struct pretty_print_context ctx = {0};
 448                 ctx.date_mode = rev->date_mode;
 449                 ctx.output_encoding = get_log_output_encoding();
 450                 strbuf_setlen(&sb, 0);
 451                 format_commit_message(commit, format, &sb, &ctx);
 452                 strbuf_addch(&sb, '\n');
 453                 if (commit->object.flags & SYMMETRIC_LEFT)
 454                         diff_emit_submodule_del(o, sb.buf);
 455                 else
 456                         diff_emit_submodule_add(o, sb.buf);
 457         }
 458         strbuf_release(&sb);
 459 }
 460
 461 static void prepare_submodule_repo_env_no_git_dir(struct argv_array *out)
 462 {
 463         const char * const *var;
 464
 465         for (var = local_repo_env; *var; var++) {
 466                 if (strcmp(*var, CONFIG_DATA_ENVIRONMENT))
 467                         argv_array_push(out, *var);
 468         }
 469 }
 470
 471 void prepare_submodule_repo_env(struct argv_array *out)
 472 {
 473         prepare_submodule_repo_env_no_git_dir(out);
 474         argv_array_pushf(out, "%s=%s", GIT_DIR_ENVIRONMENT,
 475                          DEFAULT_GIT_DIR_ENVIRONMENT);
 476 }
 477
 478 /* Helper function to display the submodule header line prior to the full
 479  * summary output. If it can locate the submodule objects directory it will
 480  * attempt to lookup both the left and right commits and put them into the
 481  * left and right pointers.
 482  */
 483 static void show_submodule_header(struct diff_options *o, const char *path,
 484                 struct object_id *one, struct object_id *two,
 485                 unsigned dirty_submodule,
 486                 struct commit **left, struct commit **right,
 487                 struct commit_list **merge_bases)
 488 {
 489         const char *message = NULL;
 490         struct strbuf sb = STRBUF_INIT;
 491         int fast_forward = 0, fast_backward = 0;
 492
 493         if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
 494                 diff_emit_submodule_untracked(o, path);
 495
 496         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
 497                 diff_emit_submodule_modified(o, path);
 498
 499         if (is_null_oid(one))
 500                 message = "(new submodule)";
 501         else if (is_null_oid(two))
 502                 message = "(submodule deleted)";
 503
 504         if (add_submodule_odb(path)) {
 505                 if (!message)
 506                         message = "(commits not present)";
 507                 goto output_header;
 508         }
 509
 510         /*
 511          * Attempt to lookup the commit references, and determine if this is
 512          * a fast forward or fast backwards update.
 513          */
 514         *left = lookup_commit_reference(one);
 515         *right = lookup_commit_reference(two);
 516
 517         /*
 518          * Warn about missing commits in the submodule project, but only if
 519          * they aren't null.
 520          */
 521         if ((!is_null_oid(one) && !*left) ||
 522              (!is_null_oid(two) && !*right))
 523                 message = "(commits not present)";
 524
 525         *merge_bases = get_merge_bases(*left, *right);
 526         if (*merge_bases) {
 527                 if ((*merge_bases)->item == *left)
 528                         fast_forward = 1;
 529                 else if ((*merge_bases)->item == *right)
 530                         fast_backward = 1;
 531         }
 532
 533         if (!oidcmp(one, two)) {
 534                 strbuf_release(&sb);
 535                 return;
 536         }
 537
 538 output_header:
 539         strbuf_addf(&sb, "Submodule %s ", path);
 540         strbuf_add_unique_abbrev(&sb, one->hash, DEFAULT_ABBREV);
 541         strbuf_addstr(&sb, (fast_backward || fast_forward) ? ".." : "...");
 542         strbuf_add_unique_abbrev(&sb, two->hash, DEFAULT_ABBREV);
 543         if (message)
 544                 strbuf_addf(&sb, " %s\n", message);
 545         else
 546                 strbuf_addf(&sb, "%s:\n", fast_backward ? " (rewind)" : "");
 547         diff_emit_submodule_header(o, sb.buf);
 548
 549         strbuf_release(&sb);
 550 }
 551
 552 void show_submodule_summary(struct diff_options *o, const char *path,
 553                 struct object_id *one, struct object_id *two,
 554                 unsigned dirty_submodule)
 555 {
 556         struct rev_info rev;
 557         struct commit *left = NULL, *right = NULL;
 558         struct commit_list *merge_bases = NULL;
 559
 560         show_submodule_header(o, path, one, two, dirty_submodule,
 561                               &left, &right, &merge_bases);
 562
 563         /*
 564          * If we don't have both a left and a right pointer, there is no
 565          * reason to try and display a summary. The header line should contain
 566          * all the information the user needs.
 567          */
 568         if (!left || !right)
 569                 goto out;
 570
 571         /* Treat revision walker failure the same as missing commits */
 572         if (prepare_submodule_summary(&rev, path, left, right, merge_bases)) {
 573                 diff_emit_submodule_error(o, "(revision walker failed)\n");
 574                 goto out;
 575         }
 576
 577         print_submodule_summary(&rev, o);
 578
 579 out:
 580         if (merge_bases)
 581                 free_commit_list(merge_bases);
 582         clear_commit_marks(left, ~0);
 583         clear_commit_marks(right, ~0);
 584 }
 585
 586 void show_submodule_inline_diff(struct diff_options *o, const char *path,
 587                 struct object_id *one, struct object_id *two,
 588                 unsigned dirty_submodule)
 589 {
 590         const struct object_id *old = &empty_tree_oid, *new = &empty_tree_oid;
 591         struct commit *left = NULL, *right = NULL;
 592         struct commit_list *merge_bases = NULL;
 593         struct child_process cp = CHILD_PROCESS_INIT;
 594         struct strbuf sb = STRBUF_INIT;
 595
 596         show_submodule_header(o, path, one, two, dirty_submodule,
 597                               &left, &right, &merge_bases);
 598
 599         /* We need a valid left and right commit to display a difference */
 600         if (!(left || is_null_oid(one)) ||
 601             !(right || is_null_oid(two)))
 602                 goto done;
 603
 604         if (left)
 605                 old = one;
 606         if (right)
 607                 new = two;
 608
 609         cp.git_cmd = 1;
 610         cp.dir = path;
 611         cp.out = -1;
 612         cp.no_stdin = 1;
 613
 614         /* TODO: other options may need to be passed here. */
 615         argv_array_pushl(&cp.args, "diff", "--submodule=diff", NULL);
 616         argv_array_pushf(&cp.args, "--color=%s", want_color(o->use_color) ?
 617                          "always" : "never");
 618
 619         if (o->flags.reverse_diff) {
 620                 argv_array_pushf(&cp.args, "--src-prefix=%s%s/",
 621                                  o->b_prefix, path);
 622                 argv_array_pushf(&cp.args, "--dst-prefix=%s%s/",
 623                                  o->a_prefix, path);
 624         } else {
 625                 argv_array_pushf(&cp.args, "--src-prefix=%s%s/",
 626                                  o->a_prefix, path);
 627                 argv_array_pushf(&cp.args, "--dst-prefix=%s%s/",
 628                                  o->b_prefix, path);
 629         }
 630         argv_array_push(&cp.args, oid_to_hex(old));
 631         /*
 632          * If the submodule has modified content, we will diff against the
 633          * work tree, under the assumption that the user has asked for the
 634          * diff format and wishes to actually see all differences even if they
 635          * haven't yet been committed to the submodule yet.
 636          */
 637         if (!(dirty_submodule & DIRTY_SUBMODULE_MODIFIED))
 638                 argv_array_push(&cp.args, oid_to_hex(new));
 639
 640         prepare_submodule_repo_env(&cp.env_array);
 641         if (start_command(&cp))
 642                 diff_emit_submodule_error(o, "(diff failed)\n");
 643
 644         while (strbuf_getwholeline_fd(&sb, cp.out, '\n') != EOF)
 645                 diff_emit_submodule_pipethrough(o, sb.buf, sb.len);
 646
 647         if (finish_command(&cp))
 648                 diff_emit_submodule_error(o, "(diff failed)\n");
 649
 650 done:
 651         strbuf_release(&sb);
 652         if (merge_bases)
 653                 free_commit_list(merge_bases);
 654         if (left)
 655                 clear_commit_marks(left, ~0);
 656         if (right)
 657                 clear_commit_marks(right, ~0);
 658 }
 659
 660 int should_update_submodules(void)
 661 {
 662         return config_update_recurse_submodules == RECURSE_SUBMODULES_ON;
 663 }
 664
 665 const struct submodule *submodule_from_ce(const struct cache_entry *ce)
 666 {
 667         if (!S_ISGITLINK(ce->ce_mode))
 668                 return NULL;
 669
 670         if (!should_update_submodules())
 671                 return NULL;
 672
 673         return submodule_from_path(&null_oid, ce->name);
 674 }
 675
 676 static struct oid_array *submodule_commits(struct string_list *submodules,
 677                                            const char *name)
 678 {
 679         struct string_list_item *item;
 680
 681         item = string_list_insert(submodules, name);
 682         if (item->util)
 683                 return (struct oid_array *) item->util;
 684
 685         /* NEEDSWORK: should we have oid_array_init()? */
 686         item->util = xcalloc(1, sizeof(struct oid_array));
 687         return (struct oid_array *) item->util;
 688 }
 689
 690 struct collect_changed_submodules_cb_data {
 691         struct string_list *changed;
 692         const struct object_id *commit_oid;
 693 };
 694
 695 /*
 696  * this would normally be two functions: default_name_from_path() and
 697  * path_from_default_name(). Since the default name is the same as
 698  * the submodule path we can get away with just one function which only
 699  * checks whether there is a submodule in the working directory at that
 700  * location.
 701  */
 702 static const char *default_name_or_path(const char *path_or_name)
 703 {
 704         int error_code;
 705
 706         if (!is_submodule_populated_gently(path_or_name, &error_code))
 707                 return NULL;
 708
 709         return path_or_name;
 710 }
 711
 712 static void collect_changed_submodules_cb(struct diff_queue_struct *q,
 713                                           struct diff_options *options,
 714                                           void *data)
 715 {
 716         struct collect_changed_submodules_cb_data *me = data;
 717         struct string_list *changed = me->changed;
 718         const struct object_id *commit_oid = me->commit_oid;
 719         int i;
 720
 721         for (i = 0; i < q->nr; i++) {
 722                 struct diff_filepair *p = q->queue[i];
 723                 struct oid_array *commits;
 724                 const struct submodule *submodule;
 725                 const char *name;
 726
 727                 if (!S_ISGITLINK(p->two->mode))
 728                         continue;
 729
 730                 submodule = submodule_from_path(commit_oid, p->two->path);
 731                 if (submodule)
 732                         name = submodule->name;
 733                 else {
 734                         name = default_name_or_path(p->two->path);
 735                         /* make sure name does not collide with existing one */
 736                         submodule = submodule_from_name(commit_oid, name);
 737                         if (submodule) {
 738                                 warning("Submodule in commit %s at path: "
 739                                         "'%s' collides with a submodule named "
 740                                         "the same. Skipping it.",
 741                                         oid_to_hex(commit_oid), name);
 742                                 name = NULL;
 743                         }
 744                 }
 745
 746                 if (!name)
 747                         continue;
 748
 749                 commits = submodule_commits(changed, name);
 750                 oid_array_append(commits, &p->two->oid);
 751         }
 752 }
 753
 754 /*
 755  * Collect the paths of submodules in 'changed' which have changed based on
 756  * the revisions as specified in 'argv'.  Each entry in 'changed' will also
 757  * have a corresponding 'struct oid_array' (in the 'util' field) which lists
 758  * what the submodule pointers were updated to during the change.
 759  */
 760 static void collect_changed_submodules(struct string_list *changed,
 761                                        struct argv_array *argv)
 762 {
 763         struct rev_info rev;
 764         const struct commit *commit;
 765
 766         init_revisions(&rev, NULL);
 767         setup_revisions(argv->argc, argv->argv, &rev, NULL);
 768         if (prepare_revision_walk(&rev))
 769                 die("revision walk setup failed");
 770
 771         while ((commit = get_revision(&rev))) {
 772                 struct rev_info diff_rev;
 773                 struct collect_changed_submodules_cb_data data;
 774                 data.changed = changed;
 775                 data.commit_oid = &commit->object.oid;
 776
 777                 init_revisions(&diff_rev, NULL);
 778                 diff_rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
 779                 diff_rev.diffopt.format_callback = collect_changed_submodules_cb;
 780                 diff_rev.diffopt.format_callback_data = &data;
 781                 diff_tree_combined_merge(commit, 1, &diff_rev);
 782         }
 783
 784         reset_revision_walk();
 785 }
 786
 787 static void free_submodules_oids(struct string_list *submodules)
 788 {
 789         struct string_list_item *item;
 790         for_each_string_list_item(item, submodules)
 791                 oid_array_clear((struct oid_array *) item->util);
 792         string_list_clear(submodules, 1);
 793 }
 794
 795 static int has_remote(const char *refname, const struct object_id *oid,
 796                       int flags, void *cb_data)
 797 {
 798         return 1;
 799 }
 800
 801 static int append_oid_to_argv(const struct object_id *oid, void *data)
 802 {
 803         struct argv_array *argv = data;
 804         argv_array_push(argv, oid_to_hex(oid));
 805         return 0;
 806 }
 807
 808 struct has_commit_data {
 809         int result;
 810         const char *path;
 811 };
 812
 813 static int check_has_commit(const struct object_id *oid, void *data)
 814 {
 815         struct has_commit_data *cb = data;
 816
 817         enum object_type type = sha1_object_info(oid->hash, NULL);
 818
 819         switch (type) {
 820         case OBJ_COMMIT:
 821                 return 0;
 822         case OBJ_BAD:
 823                 /*
 824                  * Object is missing or invalid. If invalid, an error message
 825                  * has already been printed.
 826                  */
 827                 cb->result = 0;
 828                 return 0;
 829         default:
 830                 die(_("submodule entry '%s' (%s) is a %s, not a commit"),
 831                     cb->path, oid_to_hex(oid), typename(type));
 832         }
 833 }
 834
 835 static int submodule_has_commits(const char *path, struct oid_array *commits)
 836 {
 837         struct has_commit_data has_commit = { 1, path };
 838
 839         /*
 840          * Perform a cheap, but incorrect check for the existence of 'commits'.
 841          * This is done by adding the submodule's object store to the in-core
 842          * object store, and then querying for each commit's existence.  If we
 843          * do not have the commit object anywhere, there is no chance we have
 844          * it in the object store of the correct submodule and have it
 845          * reachable from a ref, so we can fail early without spawning rev-list
 846          * which is expensive.
 847          */
 848         if (add_submodule_odb(path))
 849                 return 0;
 850
 851         oid_array_for_each_unique(commits, check_has_commit, &has_commit);
 852
 853         if (has_commit.result) {
 854                 /*
 855                  * Even if the submodule is checked out and the commit is
 856                  * present, make sure it exists in the submodule's object store
 857                  * and that it is reachable from a ref.
 858                  */
 859                 struct child_process cp = CHILD_PROCESS_INIT;
 860                 struct strbuf out = STRBUF_INIT;
 861
 862                 argv_array_pushl(&cp.args, "rev-list", "-n", "1", NULL);
 863                 oid_array_for_each_unique(commits, append_oid_to_argv, &cp.args);
 864                 argv_array_pushl(&cp.args, "--not", "--all", NULL);
 865
 866                 prepare_submodule_repo_env(&cp.env_array);
 867                 cp.git_cmd = 1;
 868                 cp.no_stdin = 1;
 869                 cp.dir = path;
 870
 871                 if (capture_command(&cp, &out, GIT_MAX_HEXSZ + 1) || out.len)
 872                         has_commit.result = 0;
 873
 874                 strbuf_release(&out);
 875         }
 876
 877         return has_commit.result;
 878 }
 879
 880 static int submodule_needs_pushing(const char *path, struct oid_array *commits)
 881 {
 882         if (!submodule_has_commits(path, commits))
 883                 /*
 884                  * NOTE: We do consider it safe to return "no" here. The
 885                  * correct answer would be "We do not know" instead of
 886                  * "No push needed", but it is quite hard to change
 887                  * the submodule pointer without having the submodule
 888                  * around. If a user did however change the submodules
 889                  * without having the submodule around, this indicates
 890                  * an expert who knows what they are doing or a
 891                  * maintainer integrating work from other people. In
 892                  * both cases it should be safe to skip this check.
 893                  */
 894                 return 0;
 895
 896         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 897                 struct child_process cp = CHILD_PROCESS_INIT;
 898                 struct strbuf buf = STRBUF_INIT;
 899                 int needs_pushing = 0;
 900
 901                 argv_array_push(&cp.args, "rev-list");
 902                 oid_array_for_each_unique(commits, append_oid_to_argv, &cp.args);
 903                 argv_array_pushl(&cp.args, "--not", "--remotes", "-n", "1" , NULL);
 904
 905                 prepare_submodule_repo_env(&cp.env_array);
 906                 cp.git_cmd = 1;
 907                 cp.no_stdin = 1;
 908                 cp.out = -1;
 909                 cp.dir = path;
 910                 if (start_command(&cp))
 911                         die("Could not run 'git rev-list <commits> --not --remotes -n 1' command in submodule %s",
 912                                         path);
 913                 if (strbuf_read(&buf, cp.out, 41))
 914                         needs_pushing = 1;
 915                 finish_command(&cp);
 916                 close(cp.out);
 917                 strbuf_release(&buf);
 918                 return needs_pushing;
 919         }
 920
 921         return 0;
 922 }
 923
 924 int find_unpushed_submodules(struct oid_array *commits,
 925                 const char *remotes_name, struct string_list *needs_pushing)
 926 {
 927         struct string_list submodules = STRING_LIST_INIT_DUP;
 928         struct string_list_item *name;
 929         struct argv_array argv = ARGV_ARRAY_INIT;
 930
 931         /* argv.argv[0] will be ignored by setup_revisions */
 932         argv_array_push(&argv, "find_unpushed_submodules");
 933         oid_array_for_each_unique(commits, append_oid_to_argv, &argv);
 934         argv_array_push(&argv, "--not");
 935         argv_array_pushf(&argv, "--remotes=%s", remotes_name);
 936
 937         collect_changed_submodules(&submodules, &argv);
 938
 939         for_each_string_list_item(name, &submodules) {
 940                 struct oid_array *commits = name->util;
 941                 const struct submodule *submodule;
 942                 const char *path = NULL;
 943
 944                 submodule = submodule_from_name(&null_oid, name->string);
 945                 if (submodule)
 946                         path = submodule->path;
 947                 else
 948                         path = default_name_or_path(name->string);
 949
 950                 if (!path)
 951                         continue;
 952
 953                 if (submodule_needs_pushing(path, commits))
 954                         string_list_insert(needs_pushing, path);
 955         }
 956
 957         free_submodules_oids(&submodules);
 958         argv_array_clear(&argv);
 959
 960         return needs_pushing->nr;
 961 }
 962
 963 static int push_submodule(const char *path,
 964                           const struct remote *remote,
 965                           const char **refspec, int refspec_nr,
 966                           const struct string_list *push_options,
 967                           int dry_run)
 968 {
 969         if (add_submodule_odb(path))
 970                 return 1;
 971
 972         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 973                 struct child_process cp = CHILD_PROCESS_INIT;
 974                 argv_array_push(&cp.args, "push");
 975                 if (dry_run)
 976                         argv_array_push(&cp.args, "--dry-run");
 977
 978                 if (push_options && push_options->nr) {
 979                         const struct string_list_item *item;
 980                         for_each_string_list_item(item, push_options)
 981                                 argv_array_pushf(&cp.args, "--push-option=%s",
 982                                                  item->string);
 983                 }
 984
 985                 if (remote->origin != REMOTE_UNCONFIGURED) {
 986                         int i;
 987                         argv_array_push(&cp.args, remote->name);
 988                         for (i = 0; i < refspec_nr; i++)
 989                                 argv_array_push(&cp.args, refspec[i]);
 990                 }
 991
 992                 prepare_submodule_repo_env(&cp.env_array);
 993                 cp.git_cmd = 1;
 994                 cp.no_stdin = 1;
 995                 cp.dir = path;
 996                 if (run_command(&cp))
 997                         return 0;
 998                 close(cp.out);
 999         }
1000
1001         return 1;
1002 }
1003
1004 /*
1005  * Perform a check in the submodule to see if the remote and refspec work.
1006  * Die if the submodule can't be pushed.
1007  */
1008 static void submodule_push_check(const char *path, const char *head,
1009                                  const struct remote *remote,
1010                                  const char **refspec, int refspec_nr)
1011 {
1012         struct child_process cp = CHILD_PROCESS_INIT;
1013         int i;
1014
1015         argv_array_push(&cp.args, "submodule--helper");
1016         argv_array_push(&cp.args, "push-check");
1017         argv_array_push(&cp.args, head);
1018         argv_array_push(&cp.args, remote->name);
1019
1020         for (i = 0; i < refspec_nr; i++)
1021                 argv_array_push(&cp.args, refspec[i]);
1022
1023         prepare_submodule_repo_env(&cp.env_array);
1024         cp.git_cmd = 1;
1025         cp.no_stdin = 1;
1026         cp.no_stdout = 1;
1027         cp.dir = path;
1028
1029         /*
1030          * Simply indicate if 'submodule--helper push-check' failed.
1031          * More detailed error information will be provided by the
1032          * child process.
1033          */
1034         if (run_command(&cp))
1035                 die("process for submodule '%s' failed", path);
1036 }
1037
1038 int push_unpushed_submodules(struct oid_array *commits,
1039                              const struct remote *remote,
1040                              const char **refspec, int refspec_nr,
1041                              const struct string_list *push_options,
1042                              int dry_run)
1043 {
1044         int i, ret = 1;
1045         struct string_list needs_pushing = STRING_LIST_INIT_DUP;
1046
1047         if (!find_unpushed_submodules(commits, remote->name, &needs_pushing))
1048                 return 1;
1049
1050         /*
1051          * Verify that the remote and refspec can be propagated to all
1052          * submodules.  This check can be skipped if the remote and refspec
1053          * won't be propagated due to the remote being unconfigured (e.g. a URL
1054          * instead of a remote name).
1055          */
1056         if (remote->origin != REMOTE_UNCONFIGURED) {
1057                 char *head;
1058                 struct object_id head_oid;
1059
1060                 head = resolve_refdup("HEAD", 0, &head_oid, NULL);
1061                 if (!head)
1062                         die(_("Failed to resolve HEAD as a valid ref."));
1063
1064                 for (i = 0; i < needs_pushing.nr; i++)
1065                         submodule_push_check(needs_pushing.items[i].string,
1066                                              head, remote,
1067                                              refspec, refspec_nr);
1068                 free(head);
1069         }
1070
1071         /* Actually push the submodules */
1072         for (i = 0; i < needs_pushing.nr; i++) {
1073                 const char *path = needs_pushing.items[i].string;
1074                 fprintf(stderr, "Pushing submodule '%s'\n", path);
1075                 if (!push_submodule(path, remote, refspec, refspec_nr,
1076                                     push_options, dry_run)) {
1077                         fprintf(stderr, "Unable to push submodule '%s'\n", path);
1078                         ret = 0;
1079                 }
1080         }
1081
1082         string_list_clear(&needs_pushing, 0);
1083
1084         return ret;
1085 }
1086
1087 static int append_oid_to_array(const char *ref, const struct object_id *oid,
1088                                int flags, void *data)
1089 {
1090         struct oid_array *array = data;
1091         oid_array_append(array, oid);
1092         return 0;
1093 }
1094
1095 void check_for_new_submodule_commits(struct object_id *oid)
1096 {
1097         if (!initialized_fetch_ref_tips) {
1098                 for_each_ref(append_oid_to_array, &ref_tips_before_fetch);
1099                 initialized_fetch_ref_tips = 1;
1100         }
1101
1102         oid_array_append(&ref_tips_after_fetch, oid);
1103 }
1104
1105 static void calculate_changed_submodule_paths(void)
1106 {
1107         struct argv_array argv = ARGV_ARRAY_INIT;
1108         struct string_list changed_submodules = STRING_LIST_INIT_DUP;
1109         const struct string_list_item *name;
1110
1111         /* No need to check if there are no submodules configured */
1112         if (!submodule_from_path(NULL, NULL))
1113                 return;
1114
1115         argv_array_push(&argv, "--"); /* argv[0] program name */
1116         oid_array_for_each_unique(&ref_tips_after_fetch,
1117                                    append_oid_to_argv, &argv);
1118         argv_array_push(&argv, "--not");
1119         oid_array_for_each_unique(&ref_tips_before_fetch,
1120                                    append_oid_to_argv, &argv);
1121
1122         /*
1123          * Collect all submodules (whether checked out or not) for which new
1124          * commits have been recorded upstream in "changed_submodule_names".
1125          */
1126         collect_changed_submodules(&changed_submodules, &argv);
1127
1128         for_each_string_list_item(name, &changed_submodules) {
1129                 struct oid_array *commits = name->util;
1130                 const struct submodule *submodule;
1131                 const char *path = NULL;
1132
1133                 submodule = submodule_from_name(&null_oid, name->string);
1134                 if (submodule)
1135                         path = submodule->path;
1136                 else
1137                         path = default_name_or_path(name->string);
1138
1139                 if (!path)
1140                         continue;
1141
1142                 if (!submodule_has_commits(path, commits))
1143                         string_list_append(&changed_submodule_names, name->string);
1144         }
1145
1146         free_submodules_oids(&changed_submodules);
1147         argv_array_clear(&argv);
1148         oid_array_clear(&ref_tips_before_fetch);
1149         oid_array_clear(&ref_tips_after_fetch);
1150         initialized_fetch_ref_tips = 0;
1151 }
1152
1153 int submodule_touches_in_range(struct object_id *excl_oid,
1154                                struct object_id *incl_oid)
1155 {
1156         struct string_list subs = STRING_LIST_INIT_DUP;
1157         struct argv_array args = ARGV_ARRAY_INIT;
1158         int ret;
1159
1160         /* No need to check if there are no submodules configured */
1161         if (!submodule_from_path(NULL, NULL))
1162                 return 0;
1163
1164         argv_array_push(&args, "--"); /* args[0] program name */
1165         argv_array_push(&args, oid_to_hex(incl_oid));
1166         argv_array_push(&args, "--not");
1167         argv_array_push(&args, oid_to_hex(excl_oid));
1168
1169         collect_changed_submodules(&subs, &args);
1170         ret = subs.nr;
1171
1172         argv_array_clear(&args);
1173
1174         free_submodules_oids(&subs);
1175         return ret;
1176 }
1177
1178 struct submodule_parallel_fetch {
1179         int count;
1180         struct argv_array args;
1181         const char *work_tree;
1182         const char *prefix;
1183         int command_line_option;
1184         int default_option;
1185         int quiet;
1186         int result;
1187 };
1188 #define SPF_INIT {0, ARGV_ARRAY_INIT, NULL, NULL, 0, 0, 0, 0}
1189
1190 static int get_fetch_recurse_config(const struct submodule *submodule,
1191                                     struct submodule_parallel_fetch *spf)
1192 {
1193         if (spf->command_line_option != RECURSE_SUBMODULES_DEFAULT)
1194                 return spf->command_line_option;
1195
1196         if (submodule) {
1197                 char *key;
1198                 const char *value;
1199
1200                 int fetch_recurse = submodule->fetch_recurse;
1201                 key = xstrfmt("submodule.%s.fetchRecurseSubmodules", submodule->name);
1202                 if (!repo_config_get_string_const(the_repository, key, &value)) {
1203                         fetch_recurse = parse_fetch_recurse_submodules_arg(key, value);
1204                 }
1205                 free(key);
1206
1207                 if (fetch_recurse != RECURSE_SUBMODULES_NONE)
1208                         /* local config overrules everything except commandline */
1209                         return fetch_recurse;
1210         }
1211
1212         return spf->default_option;
1213 }
1214
1215 static int get_next_submodule(struct child_process *cp,
1216                               struct strbuf *err, void *data, void **task_cb)
1217 {
1218         int ret = 0;
1219         struct submodule_parallel_fetch *spf = data;
1220
1221         for (; spf->count < active_nr; spf->count++) {
1222                 struct strbuf submodule_path = STRBUF_INIT;
1223                 struct strbuf submodule_git_dir = STRBUF_INIT;
1224                 struct strbuf submodule_prefix = STRBUF_INIT;
1225                 const struct cache_entry *ce = active_cache[spf->count];
1226                 const char *git_dir, *default_argv;
1227                 const struct submodule *submodule;
1228                 struct submodule default_submodule = SUBMODULE_INIT;
1229
1230                 if (!S_ISGITLINK(ce->ce_mode))
1231                         continue;
1232
1233                 submodule = submodule_from_path(&null_oid, ce->name);
1234                 if (!submodule) {
1235                         const char *name = default_name_or_path(ce->name);
1236                         if (name) {
1237                                 default_submodule.path = default_submodule.name = name;
1238                                 submodule = &default_submodule;
1239                         }
1240                 }
1241
1242                 switch (get_fetch_recurse_config(submodule, spf))
1243                 {
1244                 default:
1245                 case RECURSE_SUBMODULES_DEFAULT:
1246                 case RECURSE_SUBMODULES_ON_DEMAND:
1247                         if (!submodule || !unsorted_string_list_lookup(&changed_submodule_names,
1248                                                          submodule->name))
1249                                 continue;
1250                         default_argv = "on-demand";
1251                         break;
1252                 case RECURSE_SUBMODULES_ON:
1253                         default_argv = "yes";
1254                         break;
1255                 case RECURSE_SUBMODULES_OFF:
1256                         continue;
1257                 }
1258
1259                 strbuf_addf(&submodule_path, "%s/%s", spf->work_tree, ce->name);
1260                 strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
1261                 strbuf_addf(&submodule_prefix, "%s%s/", spf->prefix, ce->name);
1262                 git_dir = read_gitfile(submodule_git_dir.buf);
1263                 if (!git_dir)
1264                         git_dir = submodule_git_dir.buf;
1265                 if (is_directory(git_dir)) {
1266                         child_process_init(cp);
1267                         cp->dir = strbuf_detach(&submodule_path, NULL);
1268                         prepare_submodule_repo_env(&cp->env_array);
1269                         cp->git_cmd = 1;
1270                         if (!spf->quiet)
1271                                 strbuf_addf(err, "Fetching submodule %s%s\n",
1272                                             spf->prefix, ce->name);
1273                         argv_array_init(&cp->args);
1274                         argv_array_pushv(&cp->args, spf->args.argv);
1275                         argv_array_push(&cp->args, default_argv);
1276                         argv_array_push(&cp->args, "--submodule-prefix");
1277                         argv_array_push(&cp->args, submodule_prefix.buf);
1278                         ret = 1;
1279                 }
1280                 strbuf_release(&submodule_path);
1281                 strbuf_release(&submodule_git_dir);
1282                 strbuf_release(&submodule_prefix);
1283                 if (ret) {
1284                         spf->count++;
1285                         return 1;
1286                 }
1287         }
1288         return 0;
1289 }
1290
1291 static int fetch_start_failure(struct strbuf *err,
1292                                void *cb, void *task_cb)
1293 {
1294         struct submodule_parallel_fetch *spf = cb;
1295
1296         spf->result = 1;
1297
1298         return 0;
1299 }
1300
1301 static int fetch_finish(int retvalue, struct strbuf *err,
1302                         void *cb, void *task_cb)
1303 {
1304         struct submodule_parallel_fetch *spf = cb;
1305
1306         if (retvalue)
1307                 spf->result = 1;
1308
1309         return 0;
1310 }
1311
1312 int fetch_populated_submodules(const struct argv_array *options,
1313                                const char *prefix, int command_line_option,
1314                                int default_option,
1315                                int quiet, int max_parallel_jobs)
1316 {
1317         int i;
1318         struct submodule_parallel_fetch spf = SPF_INIT;
1319
1320         spf.work_tree = get_git_work_tree();
1321         spf.command_line_option = command_line_option;
1322         spf.default_option = default_option;
1323         spf.quiet = quiet;
1324         spf.prefix = prefix;
1325
1326         if (!spf.work_tree)
1327                 goto out;
1328
1329         if (read_cache() < 0)
1330                 die("index file corrupt");
1331
1332         argv_array_push(&spf.args, "fetch");
1333         for (i = 0; i < options->argc; i++)
1334                 argv_array_push(&spf.args, options->argv[i]);
1335         argv_array_push(&spf.args, "--recurse-submodules-default");
1336         /* default value, "--submodule-prefix" and its value are added later */
1337
1338         calculate_changed_submodule_paths();
1339         run_processes_parallel(max_parallel_jobs,
1340                                get_next_submodule,
1341                                fetch_start_failure,
1342                                fetch_finish,
1343                                &spf);
1344
1345         argv_array_clear(&spf.args);
1346 out:
1347         string_list_clear(&changed_submodule_names, 1);
1348         return spf.result;
1349 }
1350
1351 unsigned is_submodule_modified(const char *path, int ignore_untracked)
1352 {
1353         struct child_process cp = CHILD_PROCESS_INIT;
1354         struct strbuf buf = STRBUF_INIT;
1355         FILE *fp;
1356         unsigned dirty_submodule = 0;
1357         const char *git_dir;
1358         int ignore_cp_exit_code = 0;
1359
1360         strbuf_addf(&buf, "%s/.git", path);
1361         git_dir = read_gitfile(buf.buf);
1362         if (!git_dir)
1363                 git_dir = buf.buf;
1364         if (!is_git_directory(git_dir)) {
1365                 if (is_directory(git_dir))
1366                         die(_("'%s' not recognized as a git repository"), git_dir);
1367                 strbuf_release(&buf);
1368                 /* The submodule is not checked out, so it is not modified */
1369                 return 0;
1370         }
1371         strbuf_reset(&buf);
1372
1373         argv_array_pushl(&cp.args, "status", "--porcelain=2", NULL);
1374         if (ignore_untracked)
1375                 argv_array_push(&cp.args, "-uno");
1376
1377         prepare_submodule_repo_env(&cp.env_array);
1378         cp.git_cmd = 1;
1379         cp.no_stdin = 1;
1380         cp.out = -1;
1381         cp.dir = path;
1382         if (start_command(&cp))
1383                 die("Could not run 'git status --porcelain=2' in submodule %s", path);
1384
1385         fp = xfdopen(cp.out, "r");
1386         while (strbuf_getwholeline(&buf, fp, '\n') != EOF) {
1387                 /* regular untracked files */
1388                 if (buf.buf[0] == '?')
1389                         dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
1390
1391                 if (buf.buf[0] == 'u' ||
1392                     buf.buf[0] == '1' ||
1393                     buf.buf[0] == '2') {
1394                         /* T = line type, XY = status, SSSS = submodule state */
1395                         if (buf.len < strlen("T XY SSSS"))
1396                                 die("BUG: invalid status --porcelain=2 line %s",
1397                                     buf.buf);
1398
1399                         if (buf.buf[5] == 'S' && buf.buf[8] == 'U')
1400                                 /* nested untracked file */
1401                                 dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
1402
1403                         if (buf.buf[0] == 'u' ||
1404                             buf.buf[0] == '2' ||
1405                             memcmp(buf.buf + 5, "S..U", 4))
1406                                 /* other change */
1407                                 dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
1408                 }
1409
1410                 if ((dirty_submodule & DIRTY_SUBMODULE_MODIFIED) &&
1411                     ((dirty_submodule & DIRTY_SUBMODULE_UNTRACKED) ||
1412                      ignore_untracked)) {
1413                         /*
1414                          * We're not interested in any further information from
1415                          * the child any more, neither output nor its exit code.
1416                          */
1417                         ignore_cp_exit_code = 1;
1418                         break;
1419                 }
1420         }
1421         fclose(fp);
1422
1423         if (finish_command(&cp) && !ignore_cp_exit_code)
1424                 die("'git status --porcelain=2' failed in submodule %s", path);
1425
1426         strbuf_release(&buf);
1427         return dirty_submodule;
1428 }
1429
1430 int submodule_uses_gitfile(const char *path)
1431 {
1432         struct child_process cp = CHILD_PROCESS_INIT;
1433         const char *argv[] = {
1434                 "submodule",
1435                 "foreach",
1436                 "--quiet",
1437                 "--recursive",
1438                 "test -f .git",
1439                 NULL,
1440         };
1441         struct strbuf buf = STRBUF_INIT;
1442         const char *git_dir;
1443
1444         strbuf_addf(&buf, "%s/.git", path);
1445         git_dir = read_gitfile(buf.buf);
1446         if (!git_dir) {
1447                 strbuf_release(&buf);
1448                 return 0;
1449         }
1450         strbuf_release(&buf);
1451
1452         /* Now test that all nested submodules use a gitfile too */
1453         cp.argv = argv;
1454         prepare_submodule_repo_env(&cp.env_array);
1455         cp.git_cmd = 1;
1456         cp.no_stdin = 1;
1457         cp.no_stderr = 1;
1458         cp.no_stdout = 1;
1459         cp.dir = path;
1460         if (run_command(&cp))
1461                 return 0;
1462
1463         return 1;
1464 }
1465
1466 /*
1467  * Check if it is a bad idea to remove a submodule, i.e. if we'd lose data
1468  * when doing so.
1469  *
1470  * Return 1 if we'd lose data, return 0 if the removal is fine,
1471  * and negative values for errors.
1472  */
1473 int bad_to_remove_submodule(const char *path, unsigned flags)
1474 {
1475         ssize_t len;
1476         struct child_process cp = CHILD_PROCESS_INIT;
1477         struct strbuf buf = STRBUF_INIT;
1478         int ret = 0;
1479
1480         if (!file_exists(path) || is_empty_dir(path))
1481                 return 0;
1482
1483         if (!submodule_uses_gitfile(path))
1484                 return 1;
1485
1486         argv_array_pushl(&cp.args, "status", "--porcelain",
1487                                    "--ignore-submodules=none", NULL);
1488
1489         if (flags & SUBMODULE_REMOVAL_IGNORE_UNTRACKED)
1490                 argv_array_push(&cp.args, "-uno");
1491         else
1492                 argv_array_push(&cp.args, "-uall");
1493
1494         if (!(flags & SUBMODULE_REMOVAL_IGNORE_IGNORED_UNTRACKED))
1495                 argv_array_push(&cp.args, "--ignored");
1496
1497         prepare_submodule_repo_env(&cp.env_array);
1498         cp.git_cmd = 1;
1499         cp.no_stdin = 1;
1500         cp.out = -1;
1501         cp.dir = path;
1502         if (start_command(&cp)) {
1503                 if (flags & SUBMODULE_REMOVAL_DIE_ON_ERROR)
1504                         die(_("could not start 'git status' in submodule '%s'"),
1505                                 path);
1506                 ret = -1;
1507                 goto out;
1508         }
1509
1510         len = strbuf_read(&buf, cp.out, 1024);
1511         if (len > 2)
1512                 ret = 1;
1513         close(cp.out);
1514
1515         if (finish_command(&cp)) {
1516                 if (flags & SUBMODULE_REMOVAL_DIE_ON_ERROR)
1517                         die(_("could not run 'git status' in submodule '%s'"),
1518                                 path);
1519                 ret = -1;
1520         }
1521 out:
1522         strbuf_release(&buf);
1523         return ret;
1524 }
1525
1526 static const char *get_super_prefix_or_empty(void)
1527 {
1528         const char *s = get_super_prefix();
1529         if (!s)
1530                 s = "";
1531         return s;
1532 }
1533
1534 static int submodule_has_dirty_index(const struct submodule *sub)
1535 {
1536         struct child_process cp = CHILD_PROCESS_INIT;
1537
1538         prepare_submodule_repo_env(&cp.env_array);
1539
1540         cp.git_cmd = 1;
1541         argv_array_pushl(&cp.args, "diff-index", "--quiet",
1542                                    "--cached", "HEAD", NULL);
1543         cp.no_stdin = 1;
1544         cp.no_stdout = 1;
1545         cp.dir = sub->path;
1546         if (start_command(&cp))
1547                 die("could not recurse into submodule '%s'", sub->path);
1548
1549         return finish_command(&cp);
1550 }
1551
1552 static void submodule_reset_index(const char *path)
1553 {
1554         struct child_process cp = CHILD_PROCESS_INIT;
1555         prepare_submodule_repo_env(&cp.env_array);
1556
1557         cp.git_cmd = 1;
1558         cp.no_stdin = 1;
1559         cp.dir = path;
1560
1561         argv_array_pushf(&cp.args, "--super-prefix=%s%s/",
1562                                    get_super_prefix_or_empty(), path);
1563         argv_array_pushl(&cp.args, "read-tree", "-u", "--reset", NULL);
1564
1565         argv_array_push(&cp.args, EMPTY_TREE_SHA1_HEX);
1566
1567         if (run_command(&cp))
1568                 die("could not reset submodule index");
1569 }
1570
1571 /**
1572  * Moves a submodule at a given path from a given head to another new head.
1573  * For edge cases (a submodule coming into existence or removing a submodule)
1574  * pass NULL for old or new respectively.
1575  */
1576 int submodule_move_head(const char *path,
1577                          const char *old,
1578                          const char *new,
1579                          unsigned flags)
1580 {
1581         int ret = 0;
1582         struct child_process cp = CHILD_PROCESS_INIT;
1583         const struct submodule *sub;
1584         int *error_code_ptr, error_code;
1585
1586         if (!is_submodule_active(the_repository, path))
1587                 return 0;
1588
1589         if (flags & SUBMODULE_MOVE_HEAD_FORCE)
1590                 /*
1591                  * Pass non NULL pointer to is_submodule_populated_gently
1592                  * to prevent die()-ing. We'll use connect_work_tree_and_git_dir
1593                  * to fixup the submodule in the force case later.
1594                  */
1595                 error_code_ptr = &error_code;
1596         else
1597                 error_code_ptr = NULL;
1598
1599         if (old && !is_submodule_populated_gently(path, error_code_ptr))
1600                 return 0;
1601
1602         sub = submodule_from_path(&null_oid, path);
1603
1604         if (!sub)
1605                 die("BUG: could not get submodule information for '%s'", path);
1606
1607         if (old && !(flags & SUBMODULE_MOVE_HEAD_FORCE)) {
1608                 /* Check if the submodule has a dirty index. */
1609                 if (submodule_has_dirty_index(sub))
1610                         return error(_("submodule '%s' has dirty index"), path);
1611         }
1612
1613         if (!(flags & SUBMODULE_MOVE_HEAD_DRY_RUN)) {
1614                 if (old) {
1615                         if (!submodule_uses_gitfile(path))
1616                                 absorb_git_dir_into_superproject("", path,
1617                                         ABSORB_GITDIR_RECURSE_SUBMODULES);
1618                 } else {
1619                         char *gitdir = xstrfmt("%s/modules/%s",
1620                                     get_git_common_dir(), sub->name);
1621                         connect_work_tree_and_git_dir(path, gitdir);
1622                         free(gitdir);
1623
1624                         /* make sure the index is clean as well */
1625                         submodule_reset_index(path);
1626                 }
1627
1628                 if (old && (flags & SUBMODULE_MOVE_HEAD_FORCE)) {
1629                         char *gitdir = xstrfmt("%s/modules/%s",
1630                                     get_git_common_dir(), sub->name);
1631                         connect_work_tree_and_git_dir(path, gitdir);
1632                         free(gitdir);
1633                 }
1634         }
1635
1636         prepare_submodule_repo_env(&cp.env_array);
1637
1638         cp.git_cmd = 1;
1639         cp.no_stdin = 1;
1640         cp.dir = path;
1641
1642         argv_array_pushf(&cp.args, "--super-prefix=%s%s/",
1643                         get_super_prefix_or_empty(), path);
1644         argv_array_pushl(&cp.args, "read-tree", "--recurse-submodules", NULL);
1645
1646         if (flags & SUBMODULE_MOVE_HEAD_DRY_RUN)
1647                 argv_array_push(&cp.args, "-n");
1648         else
1649                 argv_array_push(&cp.args, "-u");
1650
1651         if (flags & SUBMODULE_MOVE_HEAD_FORCE)
1652                 argv_array_push(&cp.args, "--reset");
1653         else
1654                 argv_array_push(&cp.args, "-m");
1655
1656         argv_array_push(&cp.args, old ? old : EMPTY_TREE_SHA1_HEX);
1657         argv_array_push(&cp.args, new ? new : EMPTY_TREE_SHA1_HEX);
1658
1659         if (run_command(&cp)) {
1660                 ret = -1;
1661                 goto out;
1662         }
1663
1664         if (!(flags & SUBMODULE_MOVE_HEAD_DRY_RUN)) {
1665                 if (new) {
1666                         child_process_init(&cp);
1667                         /* also set the HEAD accordingly */
1668                         cp.git_cmd = 1;
1669                         cp.no_stdin = 1;
1670                         cp.dir = path;
1671
1672                         prepare_submodule_repo_env(&cp.env_array);
1673                         argv_array_pushl(&cp.args, "update-ref", "HEAD",
1674                                          "--no-deref", new, NULL);
1675
1676                         if (run_command(&cp)) {
1677                                 ret = -1;
1678                                 goto out;
1679                         }
1680                 } else {
1681                         struct strbuf sb = STRBUF_INIT;
1682
1683                         strbuf_addf(&sb, "%s/.git", path);
1684                         unlink_or_warn(sb.buf);
1685                         strbuf_release(&sb);
1686
1687                         if (is_empty_dir(path))
1688                                 rmdir_or_warn(path);
1689                 }
1690         }
1691 out:
1692         return ret;
1693 }
1694
1695 static int find_first_merges(struct object_array *result, const char *path,
1696                 struct commit *a, struct commit *b)
1697 {
1698         int i, j;
1699         struct object_array merges = OBJECT_ARRAY_INIT;
1700         struct commit *commit;
1701         int contains_another;
1702
1703         char merged_revision[42];
1704         const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
1705                                    "--all", merged_revision, NULL };
1706         struct rev_info revs;
1707         struct setup_revision_opt rev_opts;
1708
1709         memset(result, 0, sizeof(struct object_array));
1710         memset(&rev_opts, 0, sizeof(rev_opts));
1711
1712         /* get all revisions that merge commit a */
1713         xsnprintf(merged_revision, sizeof(merged_revision), "^%s",
1714                         oid_to_hex(&a->object.oid));
1715         init_revisions(&revs, NULL);
1716         rev_opts.submodule = path;
1717         /* FIXME: can't handle linked worktrees in submodules yet */
1718         revs.single_worktree = path != NULL;
1719         setup_revisions(ARRAY_SIZE(rev_args)-1, rev_args, &revs, &rev_opts);
1720
1721         /* save all revisions from the above list that contain b */
1722         if (prepare_revision_walk(&revs))
1723                 die("revision walk setup failed");
1724         while ((commit = get_revision(&revs)) != NULL) {
1725                 struct object *o = &(commit->object);
1726                 if (in_merge_bases(b, commit))
1727                         add_object_array(o, NULL, &merges);
1728         }
1729         reset_revision_walk();
1730
1731         /* Now we've got all merges that contain a and b. Prune all
1732          * merges that contain another found merge and save them in
1733          * result.
1734          */
1735         for (i = 0; i < merges.nr; i++) {
1736                 struct commit *m1 = (struct commit *) merges.objects[i].item;
1737
1738                 contains_another = 0;
1739                 for (j = 0; j < merges.nr; j++) {
1740                         struct commit *m2 = (struct commit *) merges.objects[j].item;
1741                         if (i != j && in_merge_bases(m2, m1)) {
1742                                 contains_another = 1;
1743                                 break;
1744                         }
1745                 }
1746
1747                 if (!contains_another)
1748                         add_object_array(merges.objects[i].item, NULL, result);
1749         }
1750
1751         object_array_clear(&merges);
1752         return result->nr;
1753 }
1754
1755 static void print_commit(struct commit *commit)
1756 {
1757         struct strbuf sb = STRBUF_INIT;
1758         struct pretty_print_context ctx = {0};
1759         ctx.date_mode.type = DATE_NORMAL;
1760         format_commit_message(commit, " %h: %m %s", &sb, &ctx);
1761         fprintf(stderr, "%s\n", sb.buf);
1762         strbuf_release(&sb);
1763 }
1764
1765 #define MERGE_WARNING(path, msg) \
1766         warning("Failed to merge submodule %s (%s)", path, msg);
1767
1768 int merge_submodule(struct object_id *result, const char *path,
1769                     const struct object_id *base, const struct object_id *a,
1770                     const struct object_id *b, int search)
1771 {
1772         struct commit *commit_base, *commit_a, *commit_b;
1773         int parent_count;
1774         struct object_array merges;
1775
1776         int i;
1777
1778         /* store a in result in case we fail */
1779         oidcpy(result, a);
1780
1781         /* we can not handle deletion conflicts */
1782         if (is_null_oid(base))
1783                 return 0;
1784         if (is_null_oid(a))
1785                 return 0;
1786         if (is_null_oid(b))
1787                 return 0;
1788
1789         if (add_submodule_odb(path)) {
1790                 MERGE_WARNING(path, "not checked out");
1791                 return 0;
1792         }
1793
1794         if (!(commit_base = lookup_commit_reference(base)) ||
1795             !(commit_a = lookup_commit_reference(a)) ||
1796             !(commit_b = lookup_commit_reference(b))) {
1797                 MERGE_WARNING(path, "commits not present");
1798                 return 0;
1799         }
1800
1801         /* check whether both changes are forward */
1802         if (!in_merge_bases(commit_base, commit_a) ||
1803             !in_merge_bases(commit_base, commit_b)) {
1804                 MERGE_WARNING(path, "commits don't follow merge-base");
1805                 return 0;
1806         }
1807
1808         /* Case #1: a is contained in b or vice versa */
1809         if (in_merge_bases(commit_a, commit_b)) {
1810                 oidcpy(result, b);
1811                 return 1;
1812         }
1813         if (in_merge_bases(commit_b, commit_a)) {
1814                 oidcpy(result, a);
1815                 return 1;
1816         }
1817
1818         /*
1819          * Case #2: There are one or more merges that contain a and b in
1820          * the submodule. If there is only one, then present it as a
1821          * suggestion to the user, but leave it marked unmerged so the
1822          * user needs to confirm the resolution.
1823          */
1824
1825         /* Skip the search if makes no sense to the calling context.  */
1826         if (!search)
1827                 return 0;
1828
1829         /* find commit which merges them */
1830         parent_count = find_first_merges(&merges, path, commit_a, commit_b);
1831         switch (parent_count) {
1832         case 0:
1833                 MERGE_WARNING(path, "merge following commits not found");
1834                 break;
1835
1836         case 1:
1837                 MERGE_WARNING(path, "not fast-forward");
1838                 fprintf(stderr, "Found a possible merge resolution "
1839                                 "for the submodule:\n");
1840                 print_commit((struct commit *) merges.objects[0].item);
1841                 fprintf(stderr,
1842                         "If this is correct simply add it to the index "
1843                         "for example\n"
1844                         "by using:\n\n"
1845                         "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1846                         "which will accept this suggestion.\n",
1847                         oid_to_hex(&merges.objects[0].item->oid), path);
1848                 break;
1849
1850         default:
1851                 MERGE_WARNING(path, "multiple merges found");
1852                 for (i = 0; i < merges.nr; i++)
1853                         print_commit((struct commit *) merges.objects[i].item);
1854         }
1855
1856         object_array_clear(&merges);
1857         return 0;
1858 }
1859
1860 /*
1861  * Embeds a single submodules git directory into the superprojects git dir,
1862  * non recursively.
1863  */
1864 static void relocate_single_git_dir_into_superproject(const char *prefix,
1865                                                       const char *path)
1866 {
1867         char *old_git_dir = NULL, *real_old_git_dir = NULL, *real_new_git_dir = NULL;
1868         const char *new_git_dir;
1869         const struct submodule *sub;
1870
1871         if (submodule_uses_worktrees(path))
1872                 die(_("relocate_gitdir for submodule '%s' with "
1873                       "more than one worktree not supported"), path);
1874
1875         old_git_dir = xstrfmt("%s/.git", path);
1876         if (read_gitfile(old_git_dir))
1877                 /* If it is an actual gitfile, it doesn't need migration. */
1878                 return;
1879
1880         real_old_git_dir = real_pathdup(old_git_dir, 1);
1881
1882         sub = submodule_from_path(&null_oid, path);
1883         if (!sub)
1884                 die(_("could not lookup name for submodule '%s'"), path);
1885
1886         new_git_dir = git_path("modules/%s", sub->name);
1887         if (safe_create_leading_directories_const(new_git_dir) < 0)
1888                 die(_("could not create directory '%s'"), new_git_dir);
1889         real_new_git_dir = real_pathdup(new_git_dir, 1);
1890
1891         fprintf(stderr, _("Migrating git directory of '%s%s' from\n'%s' to\n'%s'\n"),
1892                 get_super_prefix_or_empty(), path,
1893                 real_old_git_dir, real_new_git_dir);
1894
1895         relocate_gitdir(path, real_old_git_dir, real_new_git_dir);
1896
1897         free(old_git_dir);
1898         free(real_old_git_dir);
1899         free(real_new_git_dir);
1900 }
1901
1902 /*
1903  * Migrate the git directory of the submodule given by path from
1904  * having its git directory within the working tree to the git dir nested
1905  * in its superprojects git dir under modules/.
1906  */
1907 void absorb_git_dir_into_superproject(const char *prefix,
1908                                       const char *path,
1909                                       unsigned flags)
1910 {
1911         int err_code;
1912         const char *sub_git_dir;
1913         struct strbuf gitdir = STRBUF_INIT;
1914         strbuf_addf(&gitdir, "%s/.git", path);
1915         sub_git_dir = resolve_gitdir_gently(gitdir.buf, &err_code);
1916
1917         /* Not populated? */
1918         if (!sub_git_dir) {
1919                 const struct submodule *sub;
1920
1921                 if (err_code == READ_GITFILE_ERR_STAT_FAILED) {
1922                         /* unpopulated as expected */
1923                         strbuf_release(&gitdir);
1924                         return;
1925                 }
1926
1927                 if (err_code != READ_GITFILE_ERR_NOT_A_REPO)
1928                         /* We don't know what broke here. */
1929                         read_gitfile_error_die(err_code, path, NULL);
1930
1931                 /*
1932                 * Maybe populated, but no git directory was found?
1933                 * This can happen if the superproject is a submodule
1934                 * itself and was just absorbed. The absorption of the
1935                 * superproject did not rewrite the git file links yet,
1936                 * fix it now.
1937                 */
1938                 sub = submodule_from_path(&null_oid, path);
1939                 if (!sub)
1940                         die(_("could not lookup name for submodule '%s'"), path);
1941                 connect_work_tree_and_git_dir(path,
1942                         git_path("modules/%s", sub->name));
1943         } else {
1944                 /* Is it already absorbed into the superprojects git dir? */
1945                 char *real_sub_git_dir = real_pathdup(sub_git_dir, 1);
1946                 char *real_common_git_dir = real_pathdup(get_git_common_dir(), 1);
1947
1948                 if (!starts_with(real_sub_git_dir, real_common_git_dir))
1949                         relocate_single_git_dir_into_superproject(prefix, path);
1950
1951                 free(real_sub_git_dir);
1952                 free(real_common_git_dir);
1953         }
1954         strbuf_release(&gitdir);
1955
1956         if (flags & ABSORB_GITDIR_RECURSE_SUBMODULES) {
1957                 struct child_process cp = CHILD_PROCESS_INIT;
1958                 struct strbuf sb = STRBUF_INIT;
1959
1960                 if (flags & ~ABSORB_GITDIR_RECURSE_SUBMODULES)
1961                         die("BUG: we don't know how to pass the flags down?");
1962
1963                 strbuf_addstr(&sb, get_super_prefix_or_empty());
1964                 strbuf_addstr(&sb, path);
1965                 strbuf_addch(&sb, '/');
1966
1967                 cp.dir = path;
1968                 cp.git_cmd = 1;
1969                 cp.no_stdin = 1;
1970                 argv_array_pushl(&cp.args, "--super-prefix", sb.buf,
1971                                            "submodule--helper",
1972                                            "absorb-git-dirs", NULL);
1973                 prepare_submodule_repo_env(&cp.env_array);
1974                 if (run_command(&cp))
1975                         die(_("could not recurse into submodule '%s'"), path);
1976
1977                 strbuf_release(&sb);
1978         }
1979 }
1980
1981 const char *get_superproject_working_tree(void)
1982 {
1983         struct child_process cp = CHILD_PROCESS_INIT;
1984         struct strbuf sb = STRBUF_INIT;
1985         const char *one_up = real_path_if_valid("../");
1986         const char *cwd = xgetcwd();
1987         const char *ret = NULL;
1988         const char *subpath;
1989         int code;
1990         ssize_t len;
1991
1992         if (!is_inside_work_tree())
1993                 /*
1994                  * FIXME:
1995                  * We might have a superproject, but it is harder
1996                  * to determine.
1997                  */
1998                 return NULL;
1999
2000         if (!one_up)
2001                 return NULL;
2002
2003         subpath = relative_path(cwd, one_up, &sb);
2004
2005         prepare_submodule_repo_env(&cp.env_array);
2006         argv_array_pop(&cp.env_array);
2007
2008         argv_array_pushl(&cp.args, "--literal-pathspecs", "-C", "..",
2009                         "ls-files", "-z", "--stage", "--full-name", "--",
2010                         subpath, NULL);
2011         strbuf_reset(&sb);
2012
2013         cp.no_stdin = 1;
2014         cp.no_stderr = 1;
2015         cp.out = -1;
2016         cp.git_cmd = 1;
2017
2018         if (start_command(&cp))
2019                 die(_("could not start ls-files in .."));
2020
2021         len = strbuf_read(&sb, cp.out, PATH_MAX);
2022         close(cp.out);
2023
2024         if (starts_with(sb.buf, "160000")) {
2025                 int super_sub_len;
2026                 int cwd_len = strlen(cwd);
2027                 char *super_sub, *super_wt;
2028
2029                 /*
2030                  * There is a superproject having this repo as a submodule.
2031                  * The format is <mode> SP <hash> SP <stage> TAB <full name> \0,
2032                  * We're only interested in the name after the tab.
2033                  */
2034                 super_sub = strchr(sb.buf, '\t') + 1;
2035                 super_sub_len = sb.buf + sb.len - super_sub - 1;
2036
2037                 if (super_sub_len > cwd_len ||
2038                     strcmp(&cwd[cwd_len - super_sub_len], super_sub))
2039                         die (_("BUG: returned path string doesn't match cwd?"));
2040
2041                 super_wt = xstrdup(cwd);
2042                 super_wt[cwd_len - super_sub_len] = '\0';
2043
2044                 ret = real_path(super_wt);
2045                 free(super_wt);
2046         }
2047         strbuf_release(&sb);
2048
2049         code = finish_command(&cp);
2050
2051         if (code == 128)
2052                 /* '../' is not a git repository */
2053                 return NULL;
2054         if (code == 0 && len == 0)
2055                 /* There is an unrelated git repository at '../' */
2056                 return NULL;
2057         if (code)
2058                 die(_("ls-tree returned unexpected return code %d"), code);
2059
2060         return ret;
2061 }
2062
2063 /*
2064  * Put the gitdir for a submodule (given relative to the main
2065  * repository worktree) into `buf`, or return -1 on error.
2066  */
2067 int submodule_to_gitdir(struct strbuf *buf, const char *submodule)
2068 {
2069         const struct submodule *sub;
2070         const char *git_dir;
2071         int ret = 0;
2072
2073         strbuf_reset(buf);
2074         strbuf_addstr(buf, submodule);
2075         strbuf_complete(buf, '/');
2076         strbuf_addstr(buf, ".git");
2077
2078         git_dir = read_gitfile(buf->buf);
2079         if (git_dir) {
2080                 strbuf_reset(buf);
2081                 strbuf_addstr(buf, git_dir);
2082         }
2083         if (!is_git_directory(buf->buf)) {
2084                 sub = submodule_from_path(&null_oid, submodule);
2085                 if (!sub) {
2086                         ret = -1;
2087                         goto cleanup;
2088                 }
2089                 strbuf_reset(buf);
2090                 strbuf_git_path(buf, "%s/%s", "modules", sub->name);
2091         }
2092
2093 cleanup:
2094         return ret;
2095 }