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_fetch_recurse_submodules = RECURSE_SUBMODULES_ON_DEMAND;
  24 static int config_update_recurse_submodules = RECURSE_SUBMODULES_OFF;
  25 static struct string_list changed_submodule_paths = STRING_LIST_INIT_DUP;
  26 static int initialized_fetch_ref_tips;
  27 static struct oid_array ref_tips_before_fetch;
  28 static struct oid_array ref_tips_after_fetch;
  29
  30 /*
  31  * The following flag is set if the .gitmodules file is unmerged. We then
  32  * disable recursion for all submodules where .git/config doesn't have a
  33  * matching config entry because we can't guess what might be configured in
  34  * .gitmodules unless the user resolves the conflict. When a command line
  35  * option is given (which always overrides configuration) this flag will be
  36  * ignored.
  37  */
  38 static int gitmodules_is_unmerged;
  39
  40 /*
  41  * This flag is set if the .gitmodules file had unstaged modifications on
  42  * startup. This must be checked before allowing modifications to the
  43  * .gitmodules file with the intention to stage them later, because when
  44  * continuing we would stage the modifications the user didn't stage herself
  45  * too. That might change in a future version when we learn to stage the
  46  * changes we do ourselves without staging any previous modifications.
  47  */
  48 static int gitmodules_is_modified;
  49
  50 int is_staging_gitmodules_ok(void)
  51 {
  52         return !gitmodules_is_modified;
  53 }
  54
  55 /*
  56  * Try to update the "path" entry in the "submodule.<name>" section of the
  57  * .gitmodules file. Return 0 only if a .gitmodules file was found, a section
  58  * with the correct path=<oldpath> setting was found and we could update it.
  59  */
  60 int update_path_in_gitmodules(const char *oldpath, const char *newpath)
  61 {
  62         struct strbuf entry = STRBUF_INIT;
  63         const struct submodule *submodule;
  64
  65         if (!file_exists(GITMODULES_FILE)) /* Do nothing without .gitmodules */
  66                 return -1;
  67
  68         if (gitmodules_is_unmerged)
  69                 die(_("Cannot change unmerged .gitmodules, resolve merge conflicts first"));
  70
  71         submodule = submodule_from_path(null_sha1, oldpath);
  72         if (!submodule || !submodule->name) {
  73                 warning(_("Could not find section in .gitmodules where path=%s"), oldpath);
  74                 return -1;
  75         }
  76         strbuf_addstr(&entry, "submodule.");
  77         strbuf_addstr(&entry, submodule->name);
  78         strbuf_addstr(&entry, ".path");
  79         if (git_config_set_in_file_gently(GITMODULES_FILE, entry.buf, newpath) < 0) {
  80                 /* Maybe the user already did that, don't error out here */
  81                 warning(_("Could not update .gitmodules entry %s"), entry.buf);
  82                 strbuf_release(&entry);
  83                 return -1;
  84         }
  85         strbuf_release(&entry);
  86         return 0;
  87 }
  88
  89 /*
  90  * Try to remove the "submodule.<name>" section from .gitmodules where the given
  91  * path is configured. Return 0 only if a .gitmodules file was found, a section
  92  * with the correct path=<path> setting was found and we could remove it.
  93  */
  94 int remove_path_from_gitmodules(const char *path)
  95 {
  96         struct strbuf sect = STRBUF_INIT;
  97         const struct submodule *submodule;
  98
  99         if (!file_exists(GITMODULES_FILE)) /* Do nothing without .gitmodules */
 100                 return -1;
 101
 102         if (gitmodules_is_unmerged)
 103                 die(_("Cannot change unmerged .gitmodules, resolve merge conflicts first"));
 104
 105         submodule = submodule_from_path(null_sha1, path);
 106         if (!submodule || !submodule->name) {
 107                 warning(_("Could not find section in .gitmodules where path=%s"), path);
 108                 return -1;
 109         }
 110         strbuf_addstr(&sect, "submodule.");
 111         strbuf_addstr(&sect, submodule->name);
 112         if (git_config_rename_section_in_file(GITMODULES_FILE, sect.buf, NULL) < 0) {
 113                 /* Maybe the user already did that, don't error out here */
 114                 warning(_("Could not remove .gitmodules entry for %s"), path);
 115                 strbuf_release(&sect);
 116                 return -1;
 117         }
 118         strbuf_release(&sect);
 119         return 0;
 120 }
 121
 122 void stage_updated_gitmodules(void)
 123 {
 124         if (add_file_to_cache(GITMODULES_FILE, 0))
 125                 die(_("staging updated .gitmodules failed"));
 126 }
 127
 128 static int add_submodule_odb(const char *path)
 129 {
 130         struct strbuf objects_directory = STRBUF_INIT;
 131         int ret = 0;
 132
 133         ret = strbuf_git_path_submodule(&objects_directory, path, "objects/");
 134         if (ret)
 135                 goto done;
 136         if (!is_directory(objects_directory.buf)) {
 137                 ret = -1;
 138                 goto done;
 139         }
 140         add_to_alternates_memory(objects_directory.buf);
 141 done:
 142         strbuf_release(&objects_directory);
 143         return ret;
 144 }
 145
 146 void set_diffopt_flags_from_submodule_config(struct diff_options *diffopt,
 147                                              const char *path)
 148 {
 149         const struct submodule *submodule = submodule_from_path(null_sha1, path);
 150         if (submodule) {
 151                 if (submodule->ignore)
 152                         handle_ignore_submodules_arg(diffopt, submodule->ignore);
 153                 else if (gitmodules_is_unmerged)
 154                         DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
 155         }
 156 }
 157
 158 /* For loading from the .gitmodules file. */
 159 static int git_modules_config(const char *var, const char *value, void *cb)
 160 {
 161         if (starts_with(var, "submodule."))
 162                 return parse_submodule_config_option(var, value);
 163         else if (!strcmp(var, "fetch.recursesubmodules")) {
 164                 config_fetch_recurse_submodules = parse_fetch_recurse_submodules_arg(var, value);
 165                 return 0;
 166         }
 167         return 0;
 168 }
 169
 170 /* Loads all submodule settings from the config. */
 171 int submodule_config(const char *var, const char *value, void *cb)
 172 {
 173         if (!strcmp(var, "submodule.recurse")) {
 174                 int v = git_config_bool(var, value) ?
 175                         RECURSE_SUBMODULES_ON : RECURSE_SUBMODULES_OFF;
 176                 config_update_recurse_submodules = v;
 177                 return 0;
 178         } else {
 179                 return git_modules_config(var, value, cb);
 180         }
 181 }
 182
 183 /* Cheap function that only determines if we're interested in submodules at all */
 184 int git_default_submodule_config(const char *var, const char *value, void *cb)
 185 {
 186         if (!strcmp(var, "submodule.recurse")) {
 187                 int v = git_config_bool(var, value) ?
 188                         RECURSE_SUBMODULES_ON : RECURSE_SUBMODULES_OFF;
 189                 config_update_recurse_submodules = v;
 190         }
 191         return 0;
 192 }
 193
 194 int option_parse_recurse_submodules_worktree_updater(const struct option *opt,
 195                                                      const char *arg, int unset)
 196 {
 197         if (unset) {
 198                 config_update_recurse_submodules = RECURSE_SUBMODULES_OFF;
 199                 return 0;
 200         }
 201         if (arg)
 202                 config_update_recurse_submodules =
 203                         parse_update_recurse_submodules_arg(opt->long_name,
 204                                                             arg);
 205         else
 206                 config_update_recurse_submodules = RECURSE_SUBMODULES_ON;
 207
 208         return 0;
 209 }
 210
 211 void load_submodule_cache(void)
 212 {
 213         if (config_update_recurse_submodules == RECURSE_SUBMODULES_OFF)
 214                 return;
 215
 216         gitmodules_config();
 217         git_config(submodule_config, NULL);
 218 }
 219
 220 void gitmodules_config(void)
 221 {
 222         const char *work_tree = get_git_work_tree();
 223         if (work_tree) {
 224                 struct strbuf gitmodules_path = STRBUF_INIT;
 225                 int pos;
 226                 strbuf_addstr(&gitmodules_path, work_tree);
 227                 strbuf_addstr(&gitmodules_path, "/" GITMODULES_FILE);
 228                 if (read_cache() < 0)
 229                         die("index file corrupt");
 230                 pos = cache_name_pos(GITMODULES_FILE, 11);
 231                 if (pos < 0) { /* .gitmodules not found or isn't merged */
 232                         pos = -1 - pos;
 233                         if (active_nr > pos) {  /* there is a .gitmodules */
 234                                 const struct cache_entry *ce = active_cache[pos];
 235                                 if (ce_namelen(ce) == 11 &&
 236                                     !memcmp(ce->name, GITMODULES_FILE, 11))
 237                                         gitmodules_is_unmerged = 1;
 238                         }
 239                 } else if (pos < active_nr) {
 240                         struct stat st;
 241                         if (lstat(GITMODULES_FILE, &st) == 0 &&
 242                             ce_match_stat(active_cache[pos], &st, 0) & DATA_CHANGED)
 243                                 gitmodules_is_modified = 1;
 244                 }
 245
 246                 if (!gitmodules_is_unmerged)
 247                         git_config_from_file(git_modules_config,
 248                                 gitmodules_path.buf, NULL);
 249                 strbuf_release(&gitmodules_path);
 250         }
 251 }
 252
 253 static int gitmodules_cb(const char *var, const char *value, void *data)
 254 {
 255         struct repository *repo = data;
 256         return submodule_config_option(repo, var, value);
 257 }
 258
 259 void repo_read_gitmodules(struct repository *repo)
 260 {
 261         char *gitmodules_path = repo_worktree_path(repo, GITMODULES_FILE);
 262
 263         git_config_from_file(gitmodules_cb, gitmodules_path, repo);
 264         free(gitmodules_path);
 265 }
 266
 267 void gitmodules_config_sha1(const unsigned char *commit_sha1)
 268 {
 269         struct strbuf rev = STRBUF_INIT;
 270         unsigned char sha1[20];
 271
 272         if (gitmodule_sha1_from_commit(commit_sha1, sha1, &rev)) {
 273                 git_config_from_blob_sha1(git_modules_config, rev.buf,
 274                                           sha1, NULL);
 275         }
 276         strbuf_release(&rev);
 277 }
 278
 279 /*
 280  * Determine if a submodule has been initialized at a given 'path'
 281  */
 282 int is_submodule_active(struct repository *repo, const char *path)
 283 {
 284         int ret = 0;
 285         char *key = NULL;
 286         char *value = NULL;
 287         const struct string_list *sl;
 288         const struct submodule *module;
 289
 290         module = submodule_from_cache(repo, null_sha1, path);
 291
 292         /* early return if there isn't a path->module mapping */
 293         if (!module)
 294                 return 0;
 295
 296         /* submodule.<name>.active is set */
 297         key = xstrfmt("submodule.%s.active", module->name);
 298         if (!repo_config_get_bool(repo, key, &ret)) {
 299                 free(key);
 300                 return ret;
 301         }
 302         free(key);
 303
 304         /* submodule.active is set */
 305         sl = repo_config_get_value_multi(repo, "submodule.active");
 306         if (sl) {
 307                 struct pathspec ps;
 308                 struct argv_array args = ARGV_ARRAY_INIT;
 309                 const struct string_list_item *item;
 310
 311                 for_each_string_list_item(item, sl) {
 312                         argv_array_push(&args, item->string);
 313                 }
 314
 315                 parse_pathspec(&ps, 0, 0, NULL, args.argv);
 316                 ret = match_pathspec(&ps, path, strlen(path), 0, NULL, 1);
 317
 318                 argv_array_clear(&args);
 319                 clear_pathspec(&ps);
 320                 return ret;
 321         }
 322
 323         /* fallback to checking if the URL is set */
 324         key = xstrfmt("submodule.%s.url", module->name);
 325         ret = !repo_config_get_string(repo, key, &value);
 326
 327         free(value);
 328         free(key);
 329         return ret;
 330 }
 331
 332 int is_submodule_populated_gently(const char *path, int *return_error_code)
 333 {
 334         int ret = 0;
 335         char *gitdir = xstrfmt("%s/.git", path);
 336
 337         if (resolve_gitdir_gently(gitdir, return_error_code))
 338                 ret = 1;
 339
 340         free(gitdir);
 341         return ret;
 342 }
 343
 344 /*
 345  * Dies if the provided 'prefix' corresponds to an unpopulated submodule
 346  */
 347 void die_in_unpopulated_submodule(const struct index_state *istate,
 348                                   const char *prefix)
 349 {
 350         int i, prefixlen;
 351
 352         if (!prefix)
 353                 return;
 354
 355         prefixlen = strlen(prefix);
 356
 357         for (i = 0; i < istate->cache_nr; i++) {
 358                 struct cache_entry *ce = istate->cache[i];
 359                 int ce_len = ce_namelen(ce);
 360
 361                 if (!S_ISGITLINK(ce->ce_mode))
 362                         continue;
 363                 if (prefixlen <= ce_len)
 364                         continue;
 365                 if (strncmp(ce->name, prefix, ce_len))
 366                         continue;
 367                 if (prefix[ce_len] != '/')
 368                         continue;
 369
 370                 die(_("in unpopulated submodule '%s'"), ce->name);
 371         }
 372 }
 373
 374 /*
 375  * Dies if any paths in the provided pathspec descends into a submodule
 376  */
 377 void die_path_inside_submodule(const struct index_state *istate,
 378                                const struct pathspec *ps)
 379 {
 380         int i, j;
 381
 382         for (i = 0; i < istate->cache_nr; i++) {
 383                 struct cache_entry *ce = istate->cache[i];
 384                 int ce_len = ce_namelen(ce);
 385
 386                 if (!S_ISGITLINK(ce->ce_mode))
 387                         continue;
 388
 389                 for (j = 0; j < ps->nr ; j++) {
 390                         const struct pathspec_item *item = &ps->items[j];
 391
 392                         if (item->len <= ce_len)
 393                                 continue;
 394                         if (item->match[ce_len] != '/')
 395                                 continue;
 396                         if (strncmp(ce->name, item->match, ce_len))
 397                                 continue;
 398                         if (item->len == ce_len + 1)
 399                                 continue;
 400
 401                         die(_("Pathspec '%s' is in submodule '%.*s'"),
 402                             item->original, ce_len, ce->name);
 403                 }
 404         }
 405 }
 406
 407 int parse_submodule_update_strategy(const char *value,
 408                 struct submodule_update_strategy *dst)
 409 {
 410         free((void*)dst->command);
 411         dst->command = NULL;
 412         if (!strcmp(value, "none"))
 413                 dst->type = SM_UPDATE_NONE;
 414         else if (!strcmp(value, "checkout"))
 415                 dst->type = SM_UPDATE_CHECKOUT;
 416         else if (!strcmp(value, "rebase"))
 417                 dst->type = SM_UPDATE_REBASE;
 418         else if (!strcmp(value, "merge"))
 419                 dst->type = SM_UPDATE_MERGE;
 420         else if (skip_prefix(value, "!", &value)) {
 421                 dst->type = SM_UPDATE_COMMAND;
 422                 dst->command = xstrdup(value);
 423         } else
 424                 return -1;
 425         return 0;
 426 }
 427
 428 const char *submodule_strategy_to_string(const struct submodule_update_strategy *s)
 429 {
 430         struct strbuf sb = STRBUF_INIT;
 431         switch (s->type) {
 432         case SM_UPDATE_CHECKOUT:
 433                 return "checkout";
 434         case SM_UPDATE_MERGE:
 435                 return "merge";
 436         case SM_UPDATE_REBASE:
 437                 return "rebase";
 438         case SM_UPDATE_NONE:
 439                 return "none";
 440         case SM_UPDATE_UNSPECIFIED:
 441                 return NULL;
 442         case SM_UPDATE_COMMAND:
 443                 strbuf_addf(&sb, "!%s", s->command);
 444                 return strbuf_detach(&sb, NULL);
 445         }
 446         return NULL;
 447 }
 448
 449 void handle_ignore_submodules_arg(struct diff_options *diffopt,
 450                                   const char *arg)
 451 {
 452         DIFF_OPT_CLR(diffopt, IGNORE_SUBMODULES);
 453         DIFF_OPT_CLR(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 454         DIFF_OPT_CLR(diffopt, IGNORE_DIRTY_SUBMODULES);
 455
 456         if (!strcmp(arg, "all"))
 457                 DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
 458         else if (!strcmp(arg, "untracked"))
 459                 DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 460         else if (!strcmp(arg, "dirty"))
 461                 DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES);
 462         else if (strcmp(arg, "none"))
 463                 die("bad --ignore-submodules argument: %s", arg);
 464 }
 465
 466 static int prepare_submodule_summary(struct rev_info *rev, const char *path,
 467                 struct commit *left, struct commit *right,
 468                 struct commit_list *merge_bases)
 469 {
 470         struct commit_list *list;
 471
 472         init_revisions(rev, NULL);
 473         setup_revisions(0, NULL, rev, NULL);
 474         rev->left_right = 1;
 475         rev->first_parent_only = 1;
 476         left->object.flags |= SYMMETRIC_LEFT;
 477         add_pending_object(rev, &left->object, path);
 478         add_pending_object(rev, &right->object, path);
 479         for (list = merge_bases; list; list = list->next) {
 480                 list->item->object.flags |= UNINTERESTING;
 481                 add_pending_object(rev, &list->item->object,
 482                         oid_to_hex(&list->item->object.oid));
 483         }
 484         return prepare_revision_walk(rev);
 485 }
 486
 487 static void print_submodule_summary(struct rev_info *rev, FILE *f,
 488                 const char *line_prefix,
 489                 const char *del, const char *add, const char *reset)
 490 {
 491         static const char format[] = "  %m %s";
 492         struct strbuf sb = STRBUF_INIT;
 493         struct commit *commit;
 494
 495         while ((commit = get_revision(rev))) {
 496                 struct pretty_print_context ctx = {0};
 497                 ctx.date_mode = rev->date_mode;
 498                 ctx.output_encoding = get_log_output_encoding();
 499                 strbuf_setlen(&sb, 0);
 500                 strbuf_addstr(&sb, line_prefix);
 501                 if (commit->object.flags & SYMMETRIC_LEFT) {
 502                         if (del)
 503                                 strbuf_addstr(&sb, del);
 504                 }
 505                 else if (add)
 506                         strbuf_addstr(&sb, add);
 507                 format_commit_message(commit, format, &sb, &ctx);
 508                 if (reset)
 509                         strbuf_addstr(&sb, reset);
 510                 strbuf_addch(&sb, '\n');
 511                 fprintf(f, "%s", sb.buf);
 512         }
 513         strbuf_release(&sb);
 514 }
 515
 516 static void prepare_submodule_repo_env_no_git_dir(struct argv_array *out)
 517 {
 518         const char * const *var;
 519
 520         for (var = local_repo_env; *var; var++) {
 521                 if (strcmp(*var, CONFIG_DATA_ENVIRONMENT))
 522                         argv_array_push(out, *var);
 523         }
 524 }
 525
 526 void prepare_submodule_repo_env(struct argv_array *out)
 527 {
 528         prepare_submodule_repo_env_no_git_dir(out);
 529         argv_array_pushf(out, "%s=%s", GIT_DIR_ENVIRONMENT,
 530                          DEFAULT_GIT_DIR_ENVIRONMENT);
 531 }
 532
 533 /* Helper function to display the submodule header line prior to the full
 534  * summary output. If it can locate the submodule objects directory it will
 535  * attempt to lookup both the left and right commits and put them into the
 536  * left and right pointers.
 537  */
 538 static void show_submodule_header(FILE *f, const char *path,
 539                 const char *line_prefix,
 540                 struct object_id *one, struct object_id *two,
 541                 unsigned dirty_submodule, const char *meta,
 542                 const char *reset,
 543                 struct commit **left, struct commit **right,
 544                 struct commit_list **merge_bases)
 545 {
 546         const char *message = NULL;
 547         struct strbuf sb = STRBUF_INIT;
 548         int fast_forward = 0, fast_backward = 0;
 549
 550         if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
 551                 fprintf(f, "%sSubmodule %s contains untracked content\n",
 552                         line_prefix, path);
 553         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
 554                 fprintf(f, "%sSubmodule %s contains modified content\n",
 555                         line_prefix, path);
 556
 557         if (is_null_oid(one))
 558                 message = "(new submodule)";
 559         else if (is_null_oid(two))
 560                 message = "(submodule deleted)";
 561
 562         if (add_submodule_odb(path)) {
 563                 if (!message)
 564                         message = "(not initialized)";
 565                 goto output_header;
 566         }
 567
 568         /*
 569          * Attempt to lookup the commit references, and determine if this is
 570          * a fast forward or fast backwards update.
 571          */
 572         *left = lookup_commit_reference(one);
 573         *right = lookup_commit_reference(two);
 574
 575         /*
 576          * Warn about missing commits in the submodule project, but only if
 577          * they aren't null.
 578          */
 579         if ((!is_null_oid(one) && !*left) ||
 580              (!is_null_oid(two) && !*right))
 581                 message = "(commits not present)";
 582
 583         *merge_bases = get_merge_bases(*left, *right);
 584         if (*merge_bases) {
 585                 if ((*merge_bases)->item == *left)
 586                         fast_forward = 1;
 587                 else if ((*merge_bases)->item == *right)
 588                         fast_backward = 1;
 589         }
 590
 591         if (!oidcmp(one, two)) {
 592                 strbuf_release(&sb);
 593                 return;
 594         }
 595
 596 output_header:
 597         strbuf_addf(&sb, "%s%sSubmodule %s ", line_prefix, meta, path);
 598         strbuf_add_unique_abbrev(&sb, one->hash, DEFAULT_ABBREV);
 599         strbuf_addstr(&sb, (fast_backward || fast_forward) ? ".." : "...");
 600         strbuf_add_unique_abbrev(&sb, two->hash, DEFAULT_ABBREV);
 601         if (message)
 602                 strbuf_addf(&sb, " %s%s\n", message, reset);
 603         else
 604                 strbuf_addf(&sb, "%s:%s\n", fast_backward ? " (rewind)" : "", reset);
 605         fwrite(sb.buf, sb.len, 1, f);
 606
 607         strbuf_release(&sb);
 608 }
 609
 610 void show_submodule_summary(FILE *f, const char *path,
 611                 const char *line_prefix,
 612                 struct object_id *one, struct object_id *two,
 613                 unsigned dirty_submodule, const char *meta,
 614                 const char *del, const char *add, const char *reset)
 615 {
 616         struct rev_info rev;
 617         struct commit *left = NULL, *right = NULL;
 618         struct commit_list *merge_bases = NULL;
 619
 620         show_submodule_header(f, path, line_prefix, one, two, dirty_submodule,
 621                               meta, reset, &left, &right, &merge_bases);
 622
 623         /*
 624          * If we don't have both a left and a right pointer, there is no
 625          * reason to try and display a summary. The header line should contain
 626          * all the information the user needs.
 627          */
 628         if (!left || !right)
 629                 goto out;
 630
 631         /* Treat revision walker failure the same as missing commits */
 632         if (prepare_submodule_summary(&rev, path, left, right, merge_bases)) {
 633                 fprintf(f, "%s(revision walker failed)\n", line_prefix);
 634                 goto out;
 635         }
 636
 637         print_submodule_summary(&rev, f, line_prefix, del, add, reset);
 638
 639 out:
 640         if (merge_bases)
 641                 free_commit_list(merge_bases);
 642         clear_commit_marks(left, ~0);
 643         clear_commit_marks(right, ~0);
 644 }
 645
 646 void show_submodule_inline_diff(FILE *f, const char *path,
 647                 const char *line_prefix,
 648                 struct object_id *one, struct object_id *two,
 649                 unsigned dirty_submodule, const char *meta,
 650                 const char *del, const char *add, const char *reset,
 651                 const struct diff_options *o)
 652 {
 653         const struct object_id *old = &empty_tree_oid, *new = &empty_tree_oid;
 654         struct commit *left = NULL, *right = NULL;
 655         struct commit_list *merge_bases = NULL;
 656         struct strbuf submodule_dir = STRBUF_INIT;
 657         struct child_process cp = CHILD_PROCESS_INIT;
 658
 659         show_submodule_header(f, path, line_prefix, one, two, dirty_submodule,
 660                               meta, reset, &left, &right, &merge_bases);
 661
 662         /* We need a valid left and right commit to display a difference */
 663         if (!(left || is_null_oid(one)) ||
 664             !(right || is_null_oid(two)))
 665                 goto done;
 666
 667         if (left)
 668                 old = one;
 669         if (right)
 670                 new = two;
 671
 672         fflush(f);
 673         cp.git_cmd = 1;
 674         cp.dir = path;
 675         cp.out = dup(fileno(f));
 676         cp.no_stdin = 1;
 677
 678         /* TODO: other options may need to be passed here. */
 679         argv_array_pushl(&cp.args, "diff", "--submodule=diff", NULL);
 680
 681         argv_array_pushf(&cp.args, "--line-prefix=%s", line_prefix);
 682         if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
 683                 argv_array_pushf(&cp.args, "--src-prefix=%s%s/",
 684                                  o->b_prefix, path);
 685                 argv_array_pushf(&cp.args, "--dst-prefix=%s%s/",
 686                                  o->a_prefix, path);
 687         } else {
 688                 argv_array_pushf(&cp.args, "--src-prefix=%s%s/",
 689                                  o->a_prefix, path);
 690                 argv_array_pushf(&cp.args, "--dst-prefix=%s%s/",
 691                                  o->b_prefix, path);
 692         }
 693         argv_array_push(&cp.args, oid_to_hex(old));
 694         /*
 695          * If the submodule has modified content, we will diff against the
 696          * work tree, under the assumption that the user has asked for the
 697          * diff format and wishes to actually see all differences even if they
 698          * haven't yet been committed to the submodule yet.
 699          */
 700         if (!(dirty_submodule & DIRTY_SUBMODULE_MODIFIED))
 701                 argv_array_push(&cp.args, oid_to_hex(new));
 702
 703         prepare_submodule_repo_env(&cp.env_array);
 704         if (run_command(&cp))
 705                 fprintf(f, "(diff failed)\n");
 706
 707 done:
 708         strbuf_release(&submodule_dir);
 709         if (merge_bases)
 710                 free_commit_list(merge_bases);
 711         if (left)
 712                 clear_commit_marks(left, ~0);
 713         if (right)
 714                 clear_commit_marks(right, ~0);
 715 }
 716
 717 void set_config_fetch_recurse_submodules(int value)
 718 {
 719         config_fetch_recurse_submodules = value;
 720 }
 721
 722 int should_update_submodules(void)
 723 {
 724         return config_update_recurse_submodules == RECURSE_SUBMODULES_ON;
 725 }
 726
 727 const struct submodule *submodule_from_ce(const struct cache_entry *ce)
 728 {
 729         if (!S_ISGITLINK(ce->ce_mode))
 730                 return NULL;
 731
 732         if (!should_update_submodules())
 733                 return NULL;
 734
 735         return submodule_from_path(null_sha1, ce->name);
 736 }
 737
 738 static struct oid_array *submodule_commits(struct string_list *submodules,
 739                                            const char *path)
 740 {
 741         struct string_list_item *item;
 742
 743         item = string_list_insert(submodules, path);
 744         if (item->util)
 745                 return (struct oid_array *) item->util;
 746
 747         /* NEEDSWORK: should we have oid_array_init()? */
 748         item->util = xcalloc(1, sizeof(struct oid_array));
 749         return (struct oid_array *) item->util;
 750 }
 751
 752 static void collect_changed_submodules_cb(struct diff_queue_struct *q,
 753                                           struct diff_options *options,
 754                                           void *data)
 755 {
 756         int i;
 757         struct string_list *changed = data;
 758
 759         for (i = 0; i < q->nr; i++) {
 760                 struct diff_filepair *p = q->queue[i];
 761                 struct oid_array *commits;
 762                 if (!S_ISGITLINK(p->two->mode))
 763                         continue;
 764
 765                 if (S_ISGITLINK(p->one->mode)) {
 766                         /*
 767                          * NEEDSWORK: We should honor the name configured in
 768                          * the .gitmodules file of the commit we are examining
 769                          * here to be able to correctly follow submodules
 770                          * being moved around.
 771                          */
 772                         commits = submodule_commits(changed, p->two->path);
 773                         oid_array_append(commits, &p->two->oid);
 774                 } else {
 775                         /* Submodule is new or was moved here */
 776                         /*
 777                          * NEEDSWORK: When the .git directories of submodules
 778                          * live inside the superprojects .git directory some
 779                          * day we should fetch new submodules directly into
 780                          * that location too when config or options request
 781                          * that so they can be checked out from there.
 782                          */
 783                         continue;
 784                 }
 785         }
 786 }
 787
 788 /*
 789  * Collect the paths of submodules in 'changed' which have changed based on
 790  * the revisions as specified in 'argv'.  Each entry in 'changed' will also
 791  * have a corresponding 'struct oid_array' (in the 'util' field) which lists
 792  * what the submodule pointers were updated to during the change.
 793  */
 794 static void collect_changed_submodules(struct string_list *changed,
 795                                        struct argv_array *argv)
 796 {
 797         struct rev_info rev;
 798         const struct commit *commit;
 799
 800         init_revisions(&rev, NULL);
 801         setup_revisions(argv->argc, argv->argv, &rev, NULL);
 802         if (prepare_revision_walk(&rev))
 803                 die("revision walk setup failed");
 804
 805         while ((commit = get_revision(&rev))) {
 806                 struct rev_info diff_rev;
 807
 808                 init_revisions(&diff_rev, NULL);
 809                 diff_rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
 810                 diff_rev.diffopt.format_callback = collect_changed_submodules_cb;
 811                 diff_rev.diffopt.format_callback_data = changed;
 812                 diff_tree_combined_merge(commit, 1, &diff_rev);
 813         }
 814
 815         reset_revision_walk();
 816 }
 817
 818 static void free_submodules_oids(struct string_list *submodules)
 819 {
 820         struct string_list_item *item;
 821         for_each_string_list_item(item, submodules)
 822                 oid_array_clear((struct oid_array *) item->util);
 823         string_list_clear(submodules, 1);
 824 }
 825
 826 static int has_remote(const char *refname, const struct object_id *oid,
 827                       int flags, void *cb_data)
 828 {
 829         return 1;
 830 }
 831
 832 static int append_oid_to_argv(const struct object_id *oid, void *data)
 833 {
 834         struct argv_array *argv = data;
 835         argv_array_push(argv, oid_to_hex(oid));
 836         return 0;
 837 }
 838
 839 static int check_has_commit(const struct object_id *oid, void *data)
 840 {
 841         int *has_commit = data;
 842
 843         if (!lookup_commit_reference(oid))
 844                 *has_commit = 0;
 845
 846         return 0;
 847 }
 848
 849 static int submodule_has_commits(const char *path, struct oid_array *commits)
 850 {
 851         int has_commit = 1;
 852
 853         /*
 854          * Perform a cheap, but incorrect check for the existence of 'commits'.
 855          * This is done by adding the submodule's object store to the in-core
 856          * object store, and then querying for each commit's existence.  If we
 857          * do not have the commit object anywhere, there is no chance we have
 858          * it in the object store of the correct submodule and have it
 859          * reachable from a ref, so we can fail early without spawning rev-list
 860          * which is expensive.
 861          */
 862         if (add_submodule_odb(path))
 863                 return 0;
 864
 865         oid_array_for_each_unique(commits, check_has_commit, &has_commit);
 866
 867         if (has_commit) {
 868                 /*
 869                  * Even if the submodule is checked out and the commit is
 870                  * present, make sure it exists in the submodule's object store
 871                  * and that it is reachable from a ref.
 872                  */
 873                 struct child_process cp = CHILD_PROCESS_INIT;
 874                 struct strbuf out = STRBUF_INIT;
 875
 876                 argv_array_pushl(&cp.args, "rev-list", "-n", "1", NULL);
 877                 oid_array_for_each_unique(commits, append_oid_to_argv, &cp.args);
 878                 argv_array_pushl(&cp.args, "--not", "--all", NULL);
 879
 880                 prepare_submodule_repo_env(&cp.env_array);
 881                 cp.git_cmd = 1;
 882                 cp.no_stdin = 1;
 883                 cp.dir = path;
 884
 885                 if (capture_command(&cp, &out, GIT_MAX_HEXSZ + 1) || out.len)
 886                         has_commit = 0;
 887
 888                 strbuf_release(&out);
 889         }
 890
 891         return has_commit;
 892 }
 893
 894 static int submodule_needs_pushing(const char *path, struct oid_array *commits)
 895 {
 896         if (!submodule_has_commits(path, commits))
 897                 /*
 898                  * NOTE: We do consider it safe to return "no" here. The
 899                  * correct answer would be "We do not know" instead of
 900                  * "No push needed", but it is quite hard to change
 901                  * the submodule pointer without having the submodule
 902                  * around. If a user did however change the submodules
 903                  * without having the submodule around, this indicates
 904                  * an expert who knows what they are doing or a
 905                  * maintainer integrating work from other people. In
 906                  * both cases it should be safe to skip this check.
 907                  */
 908                 return 0;
 909
 910         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 911                 struct child_process cp = CHILD_PROCESS_INIT;
 912                 struct strbuf buf = STRBUF_INIT;
 913                 int needs_pushing = 0;
 914
 915                 argv_array_push(&cp.args, "rev-list");
 916                 oid_array_for_each_unique(commits, append_oid_to_argv, &cp.args);
 917                 argv_array_pushl(&cp.args, "--not", "--remotes", "-n", "1" , NULL);
 918
 919                 prepare_submodule_repo_env(&cp.env_array);
 920                 cp.git_cmd = 1;
 921                 cp.no_stdin = 1;
 922                 cp.out = -1;
 923                 cp.dir = path;
 924                 if (start_command(&cp))
 925                         die("Could not run 'git rev-list <commits> --not --remotes -n 1' command in submodule %s",
 926                                         path);
 927                 if (strbuf_read(&buf, cp.out, 41))
 928                         needs_pushing = 1;
 929                 finish_command(&cp);
 930                 close(cp.out);
 931                 strbuf_release(&buf);
 932                 return needs_pushing;
 933         }
 934
 935         return 0;
 936 }
 937
 938 int find_unpushed_submodules(struct oid_array *commits,
 939                 const char *remotes_name, struct string_list *needs_pushing)
 940 {
 941         struct string_list submodules = STRING_LIST_INIT_DUP;
 942         struct string_list_item *submodule;
 943         struct argv_array argv = ARGV_ARRAY_INIT;
 944
 945         /* argv.argv[0] will be ignored by setup_revisions */
 946         argv_array_push(&argv, "find_unpushed_submodules");
 947         oid_array_for_each_unique(commits, append_oid_to_argv, &argv);
 948         argv_array_push(&argv, "--not");
 949         argv_array_pushf(&argv, "--remotes=%s", remotes_name);
 950
 951         collect_changed_submodules(&submodules, &argv);
 952
 953         for_each_string_list_item(submodule, &submodules) {
 954                 struct oid_array *commits = submodule->util;
 955                 const char *path = submodule->string;
 956
 957                 if (submodule_needs_pushing(path, commits))
 958                         string_list_insert(needs_pushing, path);
 959         }
 960
 961         free_submodules_oids(&submodules);
 962         argv_array_clear(&argv);
 963
 964         return needs_pushing->nr;
 965 }
 966
 967 static int push_submodule(const char *path,
 968                           const struct remote *remote,
 969                           const char **refspec, int refspec_nr,
 970                           const struct string_list *push_options,
 971                           int dry_run)
 972 {
 973         if (add_submodule_odb(path))
 974                 return 1;
 975
 976         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 977                 struct child_process cp = CHILD_PROCESS_INIT;
 978                 argv_array_push(&cp.args, "push");
 979                 if (dry_run)
 980                         argv_array_push(&cp.args, "--dry-run");
 981
 982                 if (push_options && push_options->nr) {
 983                         const struct string_list_item *item;
 984                         for_each_string_list_item(item, push_options)
 985                                 argv_array_pushf(&cp.args, "--push-option=%s",
 986                                                  item->string);
 987                 }
 988
 989                 if (remote->origin != REMOTE_UNCONFIGURED) {
 990                         int i;
 991                         argv_array_push(&cp.args, remote->name);
 992                         for (i = 0; i < refspec_nr; i++)
 993                                 argv_array_push(&cp.args, refspec[i]);
 994                 }
 995
 996                 prepare_submodule_repo_env(&cp.env_array);
 997                 cp.git_cmd = 1;
 998                 cp.no_stdin = 1;
 999                 cp.dir = path;
1000                 if (run_command(&cp))
1001                         return 0;
1002                 close(cp.out);
1003         }
1004
1005         return 1;
1006 }
1007
1008 /*
1009  * Perform a check in the submodule to see if the remote and refspec work.
1010  * Die if the submodule can't be pushed.
1011  */
1012 static void submodule_push_check(const char *path, const struct remote *remote,
1013                                  const char **refspec, int refspec_nr)
1014 {
1015         struct child_process cp = CHILD_PROCESS_INIT;
1016         int i;
1017
1018         argv_array_push(&cp.args, "submodule--helper");
1019         argv_array_push(&cp.args, "push-check");
1020         argv_array_push(&cp.args, remote->name);
1021
1022         for (i = 0; i < refspec_nr; i++)
1023                 argv_array_push(&cp.args, refspec[i]);
1024
1025         prepare_submodule_repo_env(&cp.env_array);
1026         cp.git_cmd = 1;
1027         cp.no_stdin = 1;
1028         cp.no_stdout = 1;
1029         cp.dir = path;
1030
1031         /*
1032          * Simply indicate if 'submodule--helper push-check' failed.
1033          * More detailed error information will be provided by the
1034          * child process.
1035          */
1036         if (run_command(&cp))
1037                 die("process for submodule '%s' failed", path);
1038 }
1039
1040 int push_unpushed_submodules(struct oid_array *commits,
1041                              const struct remote *remote,
1042                              const char **refspec, int refspec_nr,
1043                              const struct string_list *push_options,
1044                              int dry_run)
1045 {
1046         int i, ret = 1;
1047         struct string_list needs_pushing = STRING_LIST_INIT_DUP;
1048
1049         if (!find_unpushed_submodules(commits, remote->name, &needs_pushing))
1050                 return 1;
1051
1052         /*
1053          * Verify that the remote and refspec can be propagated to all
1054          * submodules.  This check can be skipped if the remote and refspec
1055          * won't be propagated due to the remote being unconfigured (e.g. a URL
1056          * instead of a remote name).
1057          */
1058         if (remote->origin != REMOTE_UNCONFIGURED)
1059                 for (i = 0; i < needs_pushing.nr; i++)
1060                         submodule_push_check(needs_pushing.items[i].string,
1061                                              remote, refspec, refspec_nr);
1062
1063         /* Actually push the submodules */
1064         for (i = 0; i < needs_pushing.nr; i++) {
1065                 const char *path = needs_pushing.items[i].string;
1066                 fprintf(stderr, "Pushing submodule '%s'\n", path);
1067                 if (!push_submodule(path, remote, refspec, refspec_nr,
1068                                     push_options, dry_run)) {
1069                         fprintf(stderr, "Unable to push submodule '%s'\n", path);
1070                         ret = 0;
1071                 }
1072         }
1073
1074         string_list_clear(&needs_pushing, 0);
1075
1076         return ret;
1077 }
1078
1079 static int append_oid_to_array(const char *ref, const struct object_id *oid,
1080                                int flags, void *data)
1081 {
1082         struct oid_array *array = data;
1083         oid_array_append(array, oid);
1084         return 0;
1085 }
1086
1087 void check_for_new_submodule_commits(struct object_id *oid)
1088 {
1089         if (!initialized_fetch_ref_tips) {
1090                 for_each_ref(append_oid_to_array, &ref_tips_before_fetch);
1091                 initialized_fetch_ref_tips = 1;
1092         }
1093
1094         oid_array_append(&ref_tips_after_fetch, oid);
1095 }
1096
1097 static void calculate_changed_submodule_paths(void)
1098 {
1099         struct argv_array argv = ARGV_ARRAY_INIT;
1100         struct string_list changed_submodules = STRING_LIST_INIT_DUP;
1101         const struct string_list_item *item;
1102
1103         /* No need to check if there are no submodules configured */
1104         if (!submodule_from_path(NULL, NULL))
1105                 return;
1106
1107         argv_array_push(&argv, "--"); /* argv[0] program name */
1108         oid_array_for_each_unique(&ref_tips_after_fetch,
1109                                    append_oid_to_argv, &argv);
1110         argv_array_push(&argv, "--not");
1111         oid_array_for_each_unique(&ref_tips_before_fetch,
1112                                    append_oid_to_argv, &argv);
1113
1114         /*
1115          * Collect all submodules (whether checked out or not) for which new
1116          * commits have been recorded upstream in "changed_submodule_paths".
1117          */
1118         collect_changed_submodules(&changed_submodules, &argv);
1119
1120         for_each_string_list_item(item, &changed_submodules) {
1121                 struct oid_array *commits = item->util;
1122                 const char *path = item->string;
1123
1124                 if (!submodule_has_commits(path, commits))
1125                         string_list_append(&changed_submodule_paths, path);
1126         }
1127
1128         free_submodules_oids(&changed_submodules);
1129         argv_array_clear(&argv);
1130         oid_array_clear(&ref_tips_before_fetch);
1131         oid_array_clear(&ref_tips_after_fetch);
1132         initialized_fetch_ref_tips = 0;
1133 }
1134
1135 int submodule_touches_in_range(struct object_id *excl_oid,
1136                                struct object_id *incl_oid)
1137 {
1138         struct string_list subs = STRING_LIST_INIT_DUP;
1139         struct argv_array args = ARGV_ARRAY_INIT;
1140         int ret;
1141
1142         gitmodules_config();
1143         /* No need to check if there are no submodules configured */
1144         if (!submodule_from_path(NULL, NULL))
1145                 return 0;
1146
1147         argv_array_push(&args, "--"); /* args[0] program name */
1148         argv_array_push(&args, oid_to_hex(incl_oid));
1149         argv_array_push(&args, "--not");
1150         argv_array_push(&args, oid_to_hex(excl_oid));
1151
1152         collect_changed_submodules(&subs, &args);
1153         ret = subs.nr;
1154
1155         argv_array_clear(&args);
1156
1157         free_submodules_oids(&subs);
1158         return ret;
1159 }
1160
1161 struct submodule_parallel_fetch {
1162         int count;
1163         struct argv_array args;
1164         const char *work_tree;
1165         const char *prefix;
1166         int command_line_option;
1167         int quiet;
1168         int result;
1169 };
1170 #define SPF_INIT {0, ARGV_ARRAY_INIT, NULL, NULL, 0, 0, 0}
1171
1172 static int get_next_submodule(struct child_process *cp,
1173                               struct strbuf *err, void *data, void **task_cb)
1174 {
1175         int ret = 0;
1176         struct submodule_parallel_fetch *spf = data;
1177
1178         for (; spf->count < active_nr; spf->count++) {
1179                 struct strbuf submodule_path = STRBUF_INIT;
1180                 struct strbuf submodule_git_dir = STRBUF_INIT;
1181                 struct strbuf submodule_prefix = STRBUF_INIT;
1182                 const struct cache_entry *ce = active_cache[spf->count];
1183                 const char *git_dir, *default_argv;
1184                 const struct submodule *submodule;
1185
1186                 if (!S_ISGITLINK(ce->ce_mode))
1187                         continue;
1188
1189                 submodule = submodule_from_path(null_sha1, ce->name);
1190                 if (!submodule)
1191                         submodule = submodule_from_name(null_sha1, ce->name);
1192
1193                 default_argv = "yes";
1194                 if (spf->command_line_option == RECURSE_SUBMODULES_DEFAULT) {
1195                         if (submodule &&
1196                             submodule->fetch_recurse !=
1197                                                 RECURSE_SUBMODULES_NONE) {
1198                                 if (submodule->fetch_recurse ==
1199                                                 RECURSE_SUBMODULES_OFF)
1200                                         continue;
1201                                 if (submodule->fetch_recurse ==
1202                                                 RECURSE_SUBMODULES_ON_DEMAND) {
1203                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
1204                                                 continue;
1205                                         default_argv = "on-demand";
1206                                 }
1207                         } else {
1208                                 if ((config_fetch_recurse_submodules == RECURSE_SUBMODULES_OFF) ||
1209                                     gitmodules_is_unmerged)
1210                                         continue;
1211                                 if (config_fetch_recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) {
1212                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
1213                                                 continue;
1214                                         default_argv = "on-demand";
1215                                 }
1216                         }
1217                 } else if (spf->command_line_option == RECURSE_SUBMODULES_ON_DEMAND) {
1218                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
1219                                 continue;
1220                         default_argv = "on-demand";
1221                 }
1222
1223                 strbuf_addf(&submodule_path, "%s/%s", spf->work_tree, ce->name);
1224                 strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
1225                 strbuf_addf(&submodule_prefix, "%s%s/", spf->prefix, ce->name);
1226                 git_dir = read_gitfile(submodule_git_dir.buf);
1227                 if (!git_dir)
1228                         git_dir = submodule_git_dir.buf;
1229                 if (is_directory(git_dir)) {
1230                         child_process_init(cp);
1231                         cp->dir = strbuf_detach(&submodule_path, NULL);
1232                         prepare_submodule_repo_env(&cp->env_array);
1233                         cp->git_cmd = 1;
1234                         if (!spf->quiet)
1235                                 strbuf_addf(err, "Fetching submodule %s%s\n",
1236                                             spf->prefix, ce->name);
1237                         argv_array_init(&cp->args);
1238                         argv_array_pushv(&cp->args, spf->args.argv);
1239                         argv_array_push(&cp->args, default_argv);
1240                         argv_array_push(&cp->args, "--submodule-prefix");
1241                         argv_array_push(&cp->args, submodule_prefix.buf);
1242                         ret = 1;
1243                 }
1244                 strbuf_release(&submodule_path);
1245                 strbuf_release(&submodule_git_dir);
1246                 strbuf_release(&submodule_prefix);
1247                 if (ret) {
1248                         spf->count++;
1249                         return 1;
1250                 }
1251         }
1252         return 0;
1253 }
1254
1255 static int fetch_start_failure(struct strbuf *err,
1256                                void *cb, void *task_cb)
1257 {
1258         struct submodule_parallel_fetch *spf = cb;
1259
1260         spf->result = 1;
1261
1262         return 0;
1263 }
1264
1265 static int fetch_finish(int retvalue, struct strbuf *err,
1266                         void *cb, void *task_cb)
1267 {
1268         struct submodule_parallel_fetch *spf = cb;
1269
1270         if (retvalue)
1271                 spf->result = 1;
1272
1273         return 0;
1274 }
1275
1276 int fetch_populated_submodules(const struct argv_array *options,
1277                                const char *prefix, int command_line_option,
1278                                int quiet, int max_parallel_jobs)
1279 {
1280         int i;
1281         struct submodule_parallel_fetch spf = SPF_INIT;
1282
1283         spf.work_tree = get_git_work_tree();
1284         spf.command_line_option = command_line_option;
1285         spf.quiet = quiet;
1286         spf.prefix = prefix;
1287
1288         if (!spf.work_tree)
1289                 goto out;
1290
1291         if (read_cache() < 0)
1292                 die("index file corrupt");
1293
1294         argv_array_push(&spf.args, "fetch");
1295         for (i = 0; i < options->argc; i++)
1296                 argv_array_push(&spf.args, options->argv[i]);
1297         argv_array_push(&spf.args, "--recurse-submodules-default");
1298         /* default value, "--submodule-prefix" and its value are added later */
1299
1300         calculate_changed_submodule_paths();
1301         run_processes_parallel(max_parallel_jobs,
1302                                get_next_submodule,
1303                                fetch_start_failure,
1304                                fetch_finish,
1305                                &spf);
1306
1307         argv_array_clear(&spf.args);
1308 out:
1309         string_list_clear(&changed_submodule_paths, 1);
1310         return spf.result;
1311 }
1312
1313 unsigned is_submodule_modified(const char *path, int ignore_untracked)
1314 {
1315         struct child_process cp = CHILD_PROCESS_INIT;
1316         struct strbuf buf = STRBUF_INIT;
1317         FILE *fp;
1318         unsigned dirty_submodule = 0;
1319         const char *git_dir;
1320         int ignore_cp_exit_code = 0;
1321
1322         strbuf_addf(&buf, "%s/.git", path);
1323         git_dir = read_gitfile(buf.buf);
1324         if (!git_dir)
1325                 git_dir = buf.buf;
1326         if (!is_git_directory(git_dir)) {
1327                 if (is_directory(git_dir))
1328                         die(_("'%s' not recognized as a git repository"), git_dir);
1329                 strbuf_release(&buf);
1330                 /* The submodule is not checked out, so it is not modified */
1331                 return 0;
1332         }
1333         strbuf_reset(&buf);
1334
1335         argv_array_pushl(&cp.args, "status", "--porcelain=2", NULL);
1336         if (ignore_untracked)
1337                 argv_array_push(&cp.args, "-uno");
1338
1339         prepare_submodule_repo_env(&cp.env_array);
1340         cp.git_cmd = 1;
1341         cp.no_stdin = 1;
1342         cp.out = -1;
1343         cp.dir = path;
1344         if (start_command(&cp))
1345                 die("Could not run 'git status --porcelain=2' in submodule %s", path);
1346
1347         fp = xfdopen(cp.out, "r");
1348         while (strbuf_getwholeline(&buf, fp, '\n') != EOF) {
1349                 /* regular untracked files */
1350                 if (buf.buf[0] == '?')
1351                         dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
1352
1353                 if (buf.buf[0] == 'u' ||
1354                     buf.buf[0] == '1' ||
1355                     buf.buf[0] == '2') {
1356                         /* T = line type, XY = status, SSSS = submodule state */
1357                         if (buf.len < strlen("T XY SSSS"))
1358                                 die("BUG: invalid status --porcelain=2 line %s",
1359                                     buf.buf);
1360
1361                         if (buf.buf[5] == 'S' && buf.buf[8] == 'U')
1362                                 /* nested untracked file */
1363                                 dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
1364
1365                         if (buf.buf[0] == 'u' ||
1366                             buf.buf[0] == '2' ||
1367                             memcmp(buf.buf + 5, "S..U", 4))
1368                                 /* other change */
1369                                 dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
1370                 }
1371
1372                 if ((dirty_submodule & DIRTY_SUBMODULE_MODIFIED) &&
1373                     ((dirty_submodule & DIRTY_SUBMODULE_UNTRACKED) ||
1374                      ignore_untracked)) {
1375                         /*
1376                          * We're not interested in any further information from
1377                          * the child any more, neither output nor its exit code.
1378                          */
1379                         ignore_cp_exit_code = 1;
1380                         break;
1381                 }
1382         }
1383         fclose(fp);
1384
1385         if (finish_command(&cp) && !ignore_cp_exit_code)
1386                 die("'git status --porcelain=2' failed in submodule %s", path);
1387
1388         strbuf_release(&buf);
1389         return dirty_submodule;
1390 }
1391
1392 int submodule_uses_gitfile(const char *path)
1393 {
1394         struct child_process cp = CHILD_PROCESS_INIT;
1395         const char *argv[] = {
1396                 "submodule",
1397                 "foreach",
1398                 "--quiet",
1399                 "--recursive",
1400                 "test -f .git",
1401                 NULL,
1402         };
1403         struct strbuf buf = STRBUF_INIT;
1404         const char *git_dir;
1405
1406         strbuf_addf(&buf, "%s/.git", path);
1407         git_dir = read_gitfile(buf.buf);
1408         if (!git_dir) {
1409                 strbuf_release(&buf);
1410                 return 0;
1411         }
1412         strbuf_release(&buf);
1413
1414         /* Now test that all nested submodules use a gitfile too */
1415         cp.argv = argv;
1416         prepare_submodule_repo_env(&cp.env_array);
1417         cp.git_cmd = 1;
1418         cp.no_stdin = 1;
1419         cp.no_stderr = 1;
1420         cp.no_stdout = 1;
1421         cp.dir = path;
1422         if (run_command(&cp))
1423                 return 0;
1424
1425         return 1;
1426 }
1427
1428 /*
1429  * Check if it is a bad idea to remove a submodule, i.e. if we'd lose data
1430  * when doing so.
1431  *
1432  * Return 1 if we'd lose data, return 0 if the removal is fine,
1433  * and negative values for errors.
1434  */
1435 int bad_to_remove_submodule(const char *path, unsigned flags)
1436 {
1437         ssize_t len;
1438         struct child_process cp = CHILD_PROCESS_INIT;
1439         struct strbuf buf = STRBUF_INIT;
1440         int ret = 0;
1441
1442         if (!file_exists(path) || is_empty_dir(path))
1443                 return 0;
1444
1445         if (!submodule_uses_gitfile(path))
1446                 return 1;
1447
1448         argv_array_pushl(&cp.args, "status", "--porcelain",
1449                                    "--ignore-submodules=none", NULL);
1450
1451         if (flags & SUBMODULE_REMOVAL_IGNORE_UNTRACKED)
1452                 argv_array_push(&cp.args, "-uno");
1453         else
1454                 argv_array_push(&cp.args, "-uall");
1455
1456         if (!(flags & SUBMODULE_REMOVAL_IGNORE_IGNORED_UNTRACKED))
1457                 argv_array_push(&cp.args, "--ignored");
1458
1459         prepare_submodule_repo_env(&cp.env_array);
1460         cp.git_cmd = 1;
1461         cp.no_stdin = 1;
1462         cp.out = -1;
1463         cp.dir = path;
1464         if (start_command(&cp)) {
1465                 if (flags & SUBMODULE_REMOVAL_DIE_ON_ERROR)
1466                         die(_("could not start 'git status' in submodule '%s'"),
1467                                 path);
1468                 ret = -1;
1469                 goto out;
1470         }
1471
1472         len = strbuf_read(&buf, cp.out, 1024);
1473         if (len > 2)
1474                 ret = 1;
1475         close(cp.out);
1476
1477         if (finish_command(&cp)) {
1478                 if (flags & SUBMODULE_REMOVAL_DIE_ON_ERROR)
1479                         die(_("could not run 'git status' in submodule '%s'"),
1480                                 path);
1481                 ret = -1;
1482         }
1483 out:
1484         strbuf_release(&buf);
1485         return ret;
1486 }
1487
1488 static const char *get_super_prefix_or_empty(void)
1489 {
1490         const char *s = get_super_prefix();
1491         if (!s)
1492                 s = "";
1493         return s;
1494 }
1495
1496 static int submodule_has_dirty_index(const struct submodule *sub)
1497 {
1498         struct child_process cp = CHILD_PROCESS_INIT;
1499
1500         prepare_submodule_repo_env(&cp.env_array);
1501
1502         cp.git_cmd = 1;
1503         argv_array_pushl(&cp.args, "diff-index", "--quiet",
1504                                    "--cached", "HEAD", NULL);
1505         cp.no_stdin = 1;
1506         cp.no_stdout = 1;
1507         cp.dir = sub->path;
1508         if (start_command(&cp))
1509                 die("could not recurse into submodule '%s'", sub->path);
1510
1511         return finish_command(&cp);
1512 }
1513
1514 static void submodule_reset_index(const char *path)
1515 {
1516         struct child_process cp = CHILD_PROCESS_INIT;
1517         prepare_submodule_repo_env(&cp.env_array);
1518
1519         cp.git_cmd = 1;
1520         cp.no_stdin = 1;
1521         cp.dir = path;
1522
1523         argv_array_pushf(&cp.args, "--super-prefix=%s%s/",
1524                                    get_super_prefix_or_empty(), path);
1525         argv_array_pushl(&cp.args, "read-tree", "-u", "--reset", NULL);
1526
1527         argv_array_push(&cp.args, EMPTY_TREE_SHA1_HEX);
1528
1529         if (run_command(&cp))
1530                 die("could not reset submodule index");
1531 }
1532
1533 /**
1534  * Moves a submodule at a given path from a given head to another new head.
1535  * For edge cases (a submodule coming into existence or removing a submodule)
1536  * pass NULL for old or new respectively.
1537  */
1538 int submodule_move_head(const char *path,
1539                          const char *old,
1540                          const char *new,
1541                          unsigned flags)
1542 {
1543         int ret = 0;
1544         struct child_process cp = CHILD_PROCESS_INIT;
1545         const struct submodule *sub;
1546         int *error_code_ptr, error_code;
1547
1548         if (!is_submodule_active(the_repository, path))
1549                 return 0;
1550
1551         if (flags & SUBMODULE_MOVE_HEAD_FORCE)
1552                 /*
1553                  * Pass non NULL pointer to is_submodule_populated_gently
1554                  * to prevent die()-ing. We'll use connect_work_tree_and_git_dir
1555                  * to fixup the submodule in the force case later.
1556                  */
1557                 error_code_ptr = &error_code;
1558         else
1559                 error_code_ptr = NULL;
1560
1561         if (old && !is_submodule_populated_gently(path, error_code_ptr))
1562                 return 0;
1563
1564         sub = submodule_from_path(null_sha1, path);
1565
1566         if (!sub)
1567                 die("BUG: could not get submodule information for '%s'", path);
1568
1569         if (old && !(flags & SUBMODULE_MOVE_HEAD_FORCE)) {
1570                 /* Check if the submodule has a dirty index. */
1571                 if (submodule_has_dirty_index(sub))
1572                         return error(_("submodule '%s' has dirty index"), path);
1573         }
1574
1575         if (!(flags & SUBMODULE_MOVE_HEAD_DRY_RUN)) {
1576                 if (old) {
1577                         if (!submodule_uses_gitfile(path))
1578                                 absorb_git_dir_into_superproject("", path,
1579                                         ABSORB_GITDIR_RECURSE_SUBMODULES);
1580                 } else {
1581                         char *gitdir = xstrfmt("%s/modules/%s",
1582                                     get_git_common_dir(), sub->name);
1583                         connect_work_tree_and_git_dir(path, gitdir);
1584                         free(gitdir);
1585
1586                         /* make sure the index is clean as well */
1587                         submodule_reset_index(path);
1588                 }
1589
1590                 if (old && (flags & SUBMODULE_MOVE_HEAD_FORCE)) {
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         }
1597
1598         prepare_submodule_repo_env(&cp.env_array);
1599
1600         cp.git_cmd = 1;
1601         cp.no_stdin = 1;
1602         cp.dir = path;
1603
1604         argv_array_pushf(&cp.args, "--super-prefix=%s%s/",
1605                         get_super_prefix_or_empty(), path);
1606         argv_array_pushl(&cp.args, "read-tree", "--recurse-submodules", NULL);
1607
1608         if (flags & SUBMODULE_MOVE_HEAD_DRY_RUN)
1609                 argv_array_push(&cp.args, "-n");
1610         else
1611                 argv_array_push(&cp.args, "-u");
1612
1613         if (flags & SUBMODULE_MOVE_HEAD_FORCE)
1614                 argv_array_push(&cp.args, "--reset");
1615         else
1616                 argv_array_push(&cp.args, "-m");
1617
1618         argv_array_push(&cp.args, old ? old : EMPTY_TREE_SHA1_HEX);
1619         argv_array_push(&cp.args, new ? new : EMPTY_TREE_SHA1_HEX);
1620
1621         if (run_command(&cp)) {
1622                 ret = -1;
1623                 goto out;
1624         }
1625
1626         if (!(flags & SUBMODULE_MOVE_HEAD_DRY_RUN)) {
1627                 if (new) {
1628                         child_process_init(&cp);
1629                         /* also set the HEAD accordingly */
1630                         cp.git_cmd = 1;
1631                         cp.no_stdin = 1;
1632                         cp.dir = path;
1633
1634                         prepare_submodule_repo_env(&cp.env_array);
1635                         argv_array_pushl(&cp.args, "update-ref", "HEAD", new, NULL);
1636
1637                         if (run_command(&cp)) {
1638                                 ret = -1;
1639                                 goto out;
1640                         }
1641                 } else {
1642                         struct strbuf sb = STRBUF_INIT;
1643
1644                         strbuf_addf(&sb, "%s/.git", path);
1645                         unlink_or_warn(sb.buf);
1646                         strbuf_release(&sb);
1647
1648                         if (is_empty_dir(path))
1649                                 rmdir_or_warn(path);
1650                 }
1651         }
1652 out:
1653         return ret;
1654 }
1655
1656 static int find_first_merges(struct object_array *result, const char *path,
1657                 struct commit *a, struct commit *b)
1658 {
1659         int i, j;
1660         struct object_array merges = OBJECT_ARRAY_INIT;
1661         struct commit *commit;
1662         int contains_another;
1663
1664         char merged_revision[42];
1665         const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
1666                                    "--all", merged_revision, NULL };
1667         struct rev_info revs;
1668         struct setup_revision_opt rev_opts;
1669
1670         memset(result, 0, sizeof(struct object_array));
1671         memset(&rev_opts, 0, sizeof(rev_opts));
1672
1673         /* get all revisions that merge commit a */
1674         xsnprintf(merged_revision, sizeof(merged_revision), "^%s",
1675                         oid_to_hex(&a->object.oid));
1676         init_revisions(&revs, NULL);
1677         rev_opts.submodule = path;
1678         setup_revisions(ARRAY_SIZE(rev_args)-1, rev_args, &revs, &rev_opts);
1679
1680         /* save all revisions from the above list that contain b */
1681         if (prepare_revision_walk(&revs))
1682                 die("revision walk setup failed");
1683         while ((commit = get_revision(&revs)) != NULL) {
1684                 struct object *o = &(commit->object);
1685                 if (in_merge_bases(b, commit))
1686                         add_object_array(o, NULL, &merges);
1687         }
1688         reset_revision_walk();
1689
1690         /* Now we've got all merges that contain a and b. Prune all
1691          * merges that contain another found merge and save them in
1692          * result.
1693          */
1694         for (i = 0; i < merges.nr; i++) {
1695                 struct commit *m1 = (struct commit *) merges.objects[i].item;
1696
1697                 contains_another = 0;
1698                 for (j = 0; j < merges.nr; j++) {
1699                         struct commit *m2 = (struct commit *) merges.objects[j].item;
1700                         if (i != j && in_merge_bases(m2, m1)) {
1701                                 contains_another = 1;
1702                                 break;
1703                         }
1704                 }
1705
1706                 if (!contains_another)
1707                         add_object_array(merges.objects[i].item, NULL, result);
1708         }
1709
1710         free(merges.objects);
1711         return result->nr;
1712 }
1713
1714 static void print_commit(struct commit *commit)
1715 {
1716         struct strbuf sb = STRBUF_INIT;
1717         struct pretty_print_context ctx = {0};
1718         ctx.date_mode.type = DATE_NORMAL;
1719         format_commit_message(commit, " %h: %m %s", &sb, &ctx);
1720         fprintf(stderr, "%s\n", sb.buf);
1721         strbuf_release(&sb);
1722 }
1723
1724 #define MERGE_WARNING(path, msg) \
1725         warning("Failed to merge submodule %s (%s)", path, msg);
1726
1727 int merge_submodule(struct object_id *result, const char *path,
1728                     const struct object_id *base, const struct object_id *a,
1729                     const struct object_id *b, int search)
1730 {
1731         struct commit *commit_base, *commit_a, *commit_b;
1732         int parent_count;
1733         struct object_array merges;
1734
1735         int i;
1736
1737         /* store a in result in case we fail */
1738         oidcpy(result, a);
1739
1740         /* we can not handle deletion conflicts */
1741         if (is_null_oid(base))
1742                 return 0;
1743         if (is_null_oid(a))
1744                 return 0;
1745         if (is_null_oid(b))
1746                 return 0;
1747
1748         if (add_submodule_odb(path)) {
1749                 MERGE_WARNING(path, "not checked out");
1750                 return 0;
1751         }
1752
1753         if (!(commit_base = lookup_commit_reference(base)) ||
1754             !(commit_a = lookup_commit_reference(a)) ||
1755             !(commit_b = lookup_commit_reference(b))) {
1756                 MERGE_WARNING(path, "commits not present");
1757                 return 0;
1758         }
1759
1760         /* check whether both changes are forward */
1761         if (!in_merge_bases(commit_base, commit_a) ||
1762             !in_merge_bases(commit_base, commit_b)) {
1763                 MERGE_WARNING(path, "commits don't follow merge-base");
1764                 return 0;
1765         }
1766
1767         /* Case #1: a is contained in b or vice versa */
1768         if (in_merge_bases(commit_a, commit_b)) {
1769                 oidcpy(result, b);
1770                 return 1;
1771         }
1772         if (in_merge_bases(commit_b, commit_a)) {
1773                 oidcpy(result, a);
1774                 return 1;
1775         }
1776
1777         /*
1778          * Case #2: There are one or more merges that contain a and b in
1779          * the submodule. If there is only one, then present it as a
1780          * suggestion to the user, but leave it marked unmerged so the
1781          * user needs to confirm the resolution.
1782          */
1783
1784         /* Skip the search if makes no sense to the calling context.  */
1785         if (!search)
1786                 return 0;
1787
1788         /* find commit which merges them */
1789         parent_count = find_first_merges(&merges, path, commit_a, commit_b);
1790         switch (parent_count) {
1791         case 0:
1792                 MERGE_WARNING(path, "merge following commits not found");
1793                 break;
1794
1795         case 1:
1796                 MERGE_WARNING(path, "not fast-forward");
1797                 fprintf(stderr, "Found a possible merge resolution "
1798                                 "for the submodule:\n");
1799                 print_commit((struct commit *) merges.objects[0].item);
1800                 fprintf(stderr,
1801                         "If this is correct simply add it to the index "
1802                         "for example\n"
1803                         "by using:\n\n"
1804                         "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1805                         "which will accept this suggestion.\n",
1806                         oid_to_hex(&merges.objects[0].item->oid), path);
1807                 break;
1808
1809         default:
1810                 MERGE_WARNING(path, "multiple merges found");
1811                 for (i = 0; i < merges.nr; i++)
1812                         print_commit((struct commit *) merges.objects[i].item);
1813         }
1814
1815         free(merges.objects);
1816         return 0;
1817 }
1818
1819 /*
1820  * Embeds a single submodules git directory into the superprojects git dir,
1821  * non recursively.
1822  */
1823 static void relocate_single_git_dir_into_superproject(const char *prefix,
1824                                                       const char *path)
1825 {
1826         char *old_git_dir = NULL, *real_old_git_dir = NULL, *real_new_git_dir = NULL;
1827         const char *new_git_dir;
1828         const struct submodule *sub;
1829
1830         if (submodule_uses_worktrees(path))
1831                 die(_("relocate_gitdir for submodule '%s' with "
1832                       "more than one worktree not supported"), path);
1833
1834         old_git_dir = xstrfmt("%s/.git", path);
1835         if (read_gitfile(old_git_dir))
1836                 /* If it is an actual gitfile, it doesn't need migration. */
1837                 return;
1838
1839         real_old_git_dir = real_pathdup(old_git_dir, 1);
1840
1841         sub = submodule_from_path(null_sha1, path);
1842         if (!sub)
1843                 die(_("could not lookup name for submodule '%s'"), path);
1844
1845         new_git_dir = git_path("modules/%s", sub->name);
1846         if (safe_create_leading_directories_const(new_git_dir) < 0)
1847                 die(_("could not create directory '%s'"), new_git_dir);
1848         real_new_git_dir = real_pathdup(new_git_dir, 1);
1849
1850         fprintf(stderr, _("Migrating git directory of '%s%s' from\n'%s' to\n'%s'\n"),
1851                 get_super_prefix_or_empty(), path,
1852                 real_old_git_dir, real_new_git_dir);
1853
1854         relocate_gitdir(path, real_old_git_dir, real_new_git_dir);
1855
1856         free(old_git_dir);
1857         free(real_old_git_dir);
1858         free(real_new_git_dir);
1859 }
1860
1861 /*
1862  * Migrate the git directory of the submodule given by path from
1863  * having its git directory within the working tree to the git dir nested
1864  * in its superprojects git dir under modules/.
1865  */
1866 void absorb_git_dir_into_superproject(const char *prefix,
1867                                       const char *path,
1868                                       unsigned flags)
1869 {
1870         int err_code;
1871         const char *sub_git_dir;
1872         struct strbuf gitdir = STRBUF_INIT;
1873         strbuf_addf(&gitdir, "%s/.git", path);
1874         sub_git_dir = resolve_gitdir_gently(gitdir.buf, &err_code);
1875
1876         /* Not populated? */
1877         if (!sub_git_dir) {
1878                 const struct submodule *sub;
1879
1880                 if (err_code == READ_GITFILE_ERR_STAT_FAILED) {
1881                         /* unpopulated as expected */
1882                         strbuf_release(&gitdir);
1883                         return;
1884                 }
1885
1886                 if (err_code != READ_GITFILE_ERR_NOT_A_REPO)
1887                         /* We don't know what broke here. */
1888                         read_gitfile_error_die(err_code, path, NULL);
1889
1890                 /*
1891                 * Maybe populated, but no git directory was found?
1892                 * This can happen if the superproject is a submodule
1893                 * itself and was just absorbed. The absorption of the
1894                 * superproject did not rewrite the git file links yet,
1895                 * fix it now.
1896                 */
1897                 sub = submodule_from_path(null_sha1, path);
1898                 if (!sub)
1899                         die(_("could not lookup name for submodule '%s'"), path);
1900                 connect_work_tree_and_git_dir(path,
1901                         git_path("modules/%s", sub->name));
1902         } else {
1903                 /* Is it already absorbed into the superprojects git dir? */
1904                 char *real_sub_git_dir = real_pathdup(sub_git_dir, 1);
1905                 char *real_common_git_dir = real_pathdup(get_git_common_dir(), 1);
1906
1907                 if (!starts_with(real_sub_git_dir, real_common_git_dir))
1908                         relocate_single_git_dir_into_superproject(prefix, path);
1909
1910                 free(real_sub_git_dir);
1911                 free(real_common_git_dir);
1912         }
1913         strbuf_release(&gitdir);
1914
1915         if (flags & ABSORB_GITDIR_RECURSE_SUBMODULES) {
1916                 struct child_process cp = CHILD_PROCESS_INIT;
1917                 struct strbuf sb = STRBUF_INIT;
1918
1919                 if (flags & ~ABSORB_GITDIR_RECURSE_SUBMODULES)
1920                         die("BUG: we don't know how to pass the flags down?");
1921
1922                 strbuf_addstr(&sb, get_super_prefix_or_empty());
1923                 strbuf_addstr(&sb, path);
1924                 strbuf_addch(&sb, '/');
1925
1926                 cp.dir = path;
1927                 cp.git_cmd = 1;
1928                 cp.no_stdin = 1;
1929                 argv_array_pushl(&cp.args, "--super-prefix", sb.buf,
1930                                            "submodule--helper",
1931                                            "absorb-git-dirs", NULL);
1932                 prepare_submodule_repo_env(&cp.env_array);
1933                 if (run_command(&cp))
1934                         die(_("could not recurse into submodule '%s'"), path);
1935
1936                 strbuf_release(&sb);
1937         }
1938 }
1939
1940 const char *get_superproject_working_tree(void)
1941 {
1942         struct child_process cp = CHILD_PROCESS_INIT;
1943         struct strbuf sb = STRBUF_INIT;
1944         const char *one_up = real_path_if_valid("../");
1945         const char *cwd = xgetcwd();
1946         const char *ret = NULL;
1947         const char *subpath;
1948         int code;
1949         ssize_t len;
1950
1951         if (!is_inside_work_tree())
1952                 /*
1953                  * FIXME:
1954                  * We might have a superproject, but it is harder
1955                  * to determine.
1956                  */
1957                 return NULL;
1958
1959         if (!one_up)
1960                 return NULL;
1961
1962         subpath = relative_path(cwd, one_up, &sb);
1963
1964         prepare_submodule_repo_env(&cp.env_array);
1965         argv_array_pop(&cp.env_array);
1966
1967         argv_array_pushl(&cp.args, "--literal-pathspecs", "-C", "..",
1968                         "ls-files", "-z", "--stage", "--full-name", "--",
1969                         subpath, NULL);
1970         strbuf_reset(&sb);
1971
1972         cp.no_stdin = 1;
1973         cp.no_stderr = 1;
1974         cp.out = -1;
1975         cp.git_cmd = 1;
1976
1977         if (start_command(&cp))
1978                 die(_("could not start ls-files in .."));
1979
1980         len = strbuf_read(&sb, cp.out, PATH_MAX);
1981         close(cp.out);
1982
1983         if (starts_with(sb.buf, "160000")) {
1984                 int super_sub_len;
1985                 int cwd_len = strlen(cwd);
1986                 char *super_sub, *super_wt;
1987
1988                 /*
1989                  * There is a superproject having this repo as a submodule.
1990                  * The format is <mode> SP <hash> SP <stage> TAB <full name> \0,
1991                  * We're only interested in the name after the tab.
1992                  */
1993                 super_sub = strchr(sb.buf, '\t') + 1;
1994                 super_sub_len = sb.buf + sb.len - super_sub - 1;
1995
1996                 if (super_sub_len > cwd_len ||
1997                     strcmp(&cwd[cwd_len - super_sub_len], super_sub))
1998                         die (_("BUG: returned path string doesn't match cwd?"));
1999
2000                 super_wt = xstrdup(cwd);
2001                 super_wt[cwd_len - super_sub_len] = '\0';
2002
2003                 ret = real_path(super_wt);
2004                 free(super_wt);
2005         }
2006         strbuf_release(&sb);
2007
2008         code = finish_command(&cp);
2009
2010         if (code == 128)
2011                 /* '../' is not a git repository */
2012                 return NULL;
2013         if (code == 0 && len == 0)
2014                 /* There is an unrelated git repository at '../' */
2015                 return NULL;
2016         if (code)
2017                 die(_("ls-tree returned unexpected return code %d"), code);
2018
2019         return ret;
2020 }
2021
2022 int submodule_to_gitdir(struct strbuf *buf, const char *submodule)
2023 {
2024         const struct submodule *sub;
2025         const char *git_dir;
2026         int ret = 0;
2027
2028         strbuf_reset(buf);
2029         strbuf_addstr(buf, submodule);
2030         strbuf_complete(buf, '/');
2031         strbuf_addstr(buf, ".git");
2032
2033         git_dir = read_gitfile(buf->buf);
2034         if (git_dir) {
2035                 strbuf_reset(buf);
2036                 strbuf_addstr(buf, git_dir);
2037         }
2038         if (!is_git_directory(buf->buf)) {
2039                 gitmodules_config();
2040                 sub = submodule_from_path(null_sha1, submodule);
2041                 if (!sub) {
2042                         ret = -1;
2043                         goto cleanup;
2044                 }
2045                 strbuf_reset(buf);
2046                 strbuf_git_path(buf, "%s/%s", "modules", sub->name);
2047         }
2048
2049 cleanup:
2050         return ret;
2051 }