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