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

   1 #include "cache.h"
   2 #include "submodule-config.h"
   3 #include "submodule.h"
   4 #include "dir.h"
   5 #include "diff.h"
   6 #include "commit.h"
   7 #include "revision.h"
   8 #include "run-command.h"
   9 #include "diffcore.h"
  10 #include "refs.h"
  11 #include "string-list.h"
  12 #include "sha1-array.h"
  13 #include "argv-array.h"
  14 #include "blob.h"
  15 #include "thread-utils.h"
  16 #include "quote.h"
  17 #include "worktree.h"
  18
  19 static int config_fetch_recurse_submodules = RECURSE_SUBMODULES_ON_DEMAND;
  20 static int config_update_recurse_submodules = RECURSE_SUBMODULES_DEFAULT;
  21 static int parallel_jobs = 1;
  22 static struct string_list changed_submodule_paths = STRING_LIST_INIT_NODUP;
  23 static int initialized_fetch_ref_tips;
  24 static struct sha1_array ref_tips_before_fetch;
  25 static struct sha1_array ref_tips_after_fetch;
  26
  27 /*
  28  * The following flag is set if the .gitmodules file is unmerged. We then
  29  * disable recursion for all submodules where .git/config doesn't have a
  30  * matching config entry because we can't guess what might be configured in
  31  * .gitmodules unless the user resolves the conflict. When a command line
  32  * option is given (which always overrides configuration) this flag will be
  33  * ignored.
  34  */
  35 static int gitmodules_is_unmerged;
  36
  37 /*
  38  * This flag is set if the .gitmodules file had unstaged modifications on
  39  * startup. This must be checked before allowing modifications to the
  40  * .gitmodules file with the intention to stage them later, because when
  41  * continuing we would stage the modifications the user didn't stage herself
  42  * too. That might change in a future version when we learn to stage the
  43  * changes we do ourselves without staging any previous modifications.
  44  */
  45 static int gitmodules_is_modified;
  46
  47 int is_staging_gitmodules_ok(void)
  48 {
  49         return !gitmodules_is_modified;
  50 }
  51
  52 /*
  53  * Try to update the "path" entry in the "submodule.<name>" section of the
  54  * .gitmodules file. Return 0 only if a .gitmodules file was found, a section
  55  * with the correct path=<oldpath> setting was found and we could update it.
  56  */
  57 int update_path_in_gitmodules(const char *oldpath, const char *newpath)
  58 {
  59         struct strbuf entry = STRBUF_INIT;
  60         const struct submodule *submodule;
  61
  62         if (!file_exists(".gitmodules")) /* Do nothing without .gitmodules */
  63                 return -1;
  64
  65         if (gitmodules_is_unmerged)
  66                 die(_("Cannot change unmerged .gitmodules, resolve merge conflicts first"));
  67
  68         submodule = submodule_from_path(null_sha1, oldpath);
  69         if (!submodule || !submodule->name) {
  70                 warning(_("Could not find section in .gitmodules where path=%s"), oldpath);
  71                 return -1;
  72         }
  73         strbuf_addstr(&entry, "submodule.");
  74         strbuf_addstr(&entry, submodule->name);
  75         strbuf_addstr(&entry, ".path");
  76         if (git_config_set_in_file_gently(".gitmodules", entry.buf, newpath) < 0) {
  77                 /* Maybe the user already did that, don't error out here */
  78                 warning(_("Could not update .gitmodules entry %s"), entry.buf);
  79                 strbuf_release(&entry);
  80                 return -1;
  81         }
  82         strbuf_release(&entry);
  83         return 0;
  84 }
  85
  86 /*
  87  * Try to remove the "submodule.<name>" section from .gitmodules where the given
  88  * path is configured. Return 0 only if a .gitmodules file was found, a section
  89  * with the correct path=<path> setting was found and we could remove it.
  90  */
  91 int remove_path_from_gitmodules(const char *path)
  92 {
  93         struct strbuf sect = STRBUF_INIT;
  94         const struct submodule *submodule;
  95
  96         if (!file_exists(".gitmodules")) /* Do nothing without .gitmodules */
  97                 return -1;
  98
  99         if (gitmodules_is_unmerged)
 100                 die(_("Cannot change unmerged .gitmodules, resolve merge conflicts first"));
 101
 102         submodule = submodule_from_path(null_sha1, path);
 103         if (!submodule || !submodule->name) {
 104                 warning(_("Could not find section in .gitmodules where path=%s"), path);
 105                 return -1;
 106         }
 107         strbuf_addstr(&sect, "submodule.");
 108         strbuf_addstr(&sect, submodule->name);
 109         if (git_config_rename_section_in_file(".gitmodules", sect.buf, NULL) < 0) {
 110                 /* Maybe the user already did that, don't error out here */
 111                 warning(_("Could not remove .gitmodules entry for %s"), path);
 112                 strbuf_release(&sect);
 113                 return -1;
 114         }
 115         strbuf_release(&sect);
 116         return 0;
 117 }
 118
 119 void stage_updated_gitmodules(void)
 120 {
 121         if (add_file_to_cache(".gitmodules", 0))
 122                 die(_("staging updated .gitmodules failed"));
 123 }
 124
 125 static int add_submodule_odb(const char *path)
 126 {
 127         struct strbuf objects_directory = STRBUF_INIT;
 128         int ret = 0;
 129
 130         ret = strbuf_git_path_submodule(&objects_directory, path, "objects/");
 131         if (ret)
 132                 goto done;
 133         if (!is_directory(objects_directory.buf)) {
 134                 ret = -1;
 135                 goto done;
 136         }
 137         add_to_alternates_memory(objects_directory.buf);
 138 done:
 139         strbuf_release(&objects_directory);
 140         return ret;
 141 }
 142
 143 void set_diffopt_flags_from_submodule_config(struct diff_options *diffopt,
 144                                              const char *path)
 145 {
 146         const struct submodule *submodule = submodule_from_path(null_sha1, path);
 147         if (submodule) {
 148                 if (submodule->ignore)
 149                         handle_ignore_submodules_arg(diffopt, submodule->ignore);
 150                 else if (gitmodules_is_unmerged)
 151                         DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
 152         }
 153 }
 154
 155 int submodule_config(const char *var, const char *value, void *cb)
 156 {
 157         if (!strcmp(var, "submodule.fetchjobs")) {
 158                 parallel_jobs = git_config_int(var, value);
 159                 if (parallel_jobs < 0)
 160                         die(_("negative values not allowed for submodule.fetchJobs"));
 161                 return 0;
 162         } else if (starts_with(var, "submodule."))
 163                 return parse_submodule_config_option(var, value);
 164         else if (!strcmp(var, "fetch.recursesubmodules")) {
 165                 config_fetch_recurse_submodules = parse_fetch_recurse_submodules_arg(var, value);
 166                 return 0;
 167         }
 168         return 0;
 169 }
 170
 171 void gitmodules_config(void)
 172 {
 173         const char *work_tree = get_git_work_tree();
 174         if (work_tree) {
 175                 struct strbuf gitmodules_path = STRBUF_INIT;
 176                 int pos;
 177                 strbuf_addstr(&gitmodules_path, work_tree);
 178                 strbuf_addstr(&gitmodules_path, "/.gitmodules");
 179                 if (read_cache() < 0)
 180                         die("index file corrupt");
 181                 pos = cache_name_pos(".gitmodules", 11);
 182                 if (pos < 0) { /* .gitmodules not found or isn't merged */
 183                         pos = -1 - pos;
 184                         if (active_nr > pos) {  /* there is a .gitmodules */
 185                                 const struct cache_entry *ce = active_cache[pos];
 186                                 if (ce_namelen(ce) == 11 &&
 187                                     !memcmp(ce->name, ".gitmodules", 11))
 188                                         gitmodules_is_unmerged = 1;
 189                         }
 190                 } else if (pos < active_nr) {
 191                         struct stat st;
 192                         if (lstat(".gitmodules", &st) == 0 &&
 193                             ce_match_stat(active_cache[pos], &st, 0) & DATA_CHANGED)
 194                                 gitmodules_is_modified = 1;
 195                 }
 196
 197                 if (!gitmodules_is_unmerged)
 198                         git_config_from_file(submodule_config, gitmodules_path.buf, NULL);
 199                 strbuf_release(&gitmodules_path);
 200         }
 201 }
 202
 203 void gitmodules_config_sha1(const unsigned char *commit_sha1)
 204 {
 205         struct strbuf rev = STRBUF_INIT;
 206         unsigned char sha1[20];
 207
 208         if (gitmodule_sha1_from_commit(commit_sha1, sha1, &rev)) {
 209                 git_config_from_blob_sha1(submodule_config, rev.buf,
 210                                           sha1, NULL);
 211         }
 212         strbuf_release(&rev);
 213 }
 214
 215 /*
 216  * Determine if a submodule has been initialized at a given 'path'
 217  */
 218 int is_submodule_initialized(const char *path)
 219 {
 220         int ret = 0;
 221         const struct submodule *module = NULL;
 222
 223         module = submodule_from_path(null_sha1, path);
 224
 225         if (module) {
 226                 char *key = xstrfmt("submodule.%s.url", module->name);
 227                 char *value = NULL;
 228
 229                 ret = !git_config_get_string(key, &value);
 230
 231                 free(value);
 232                 free(key);
 233         }
 234
 235         return ret;
 236 }
 237
 238 int is_submodule_populated_gently(const char *path, int *return_error_code)
 239 {
 240         int ret = 0;
 241         char *gitdir = xstrfmt("%s/.git", path);
 242
 243         if (resolve_gitdir_gently(gitdir, return_error_code))
 244                 ret = 1;
 245
 246         free(gitdir);
 247         return ret;
 248 }
 249
 250 int parse_submodule_update_strategy(const char *value,
 251                 struct submodule_update_strategy *dst)
 252 {
 253         free((void*)dst->command);
 254         dst->command = NULL;
 255         if (!strcmp(value, "none"))
 256                 dst->type = SM_UPDATE_NONE;
 257         else if (!strcmp(value, "checkout"))
 258                 dst->type = SM_UPDATE_CHECKOUT;
 259         else if (!strcmp(value, "rebase"))
 260                 dst->type = SM_UPDATE_REBASE;
 261         else if (!strcmp(value, "merge"))
 262                 dst->type = SM_UPDATE_MERGE;
 263         else if (skip_prefix(value, "!", &value)) {
 264                 dst->type = SM_UPDATE_COMMAND;
 265                 dst->command = xstrdup(value);
 266         } else
 267                 return -1;
 268         return 0;
 269 }
 270
 271 const char *submodule_strategy_to_string(const struct submodule_update_strategy *s)
 272 {
 273         struct strbuf sb = STRBUF_INIT;
 274         switch (s->type) {
 275         case SM_UPDATE_CHECKOUT:
 276                 return "checkout";
 277         case SM_UPDATE_MERGE:
 278                 return "merge";
 279         case SM_UPDATE_REBASE:
 280                 return "rebase";
 281         case SM_UPDATE_NONE:
 282                 return "none";
 283         case SM_UPDATE_UNSPECIFIED:
 284                 return NULL;
 285         case SM_UPDATE_COMMAND:
 286                 strbuf_addf(&sb, "!%s", s->command);
 287                 return strbuf_detach(&sb, NULL);
 288         }
 289         return NULL;
 290 }
 291
 292 void handle_ignore_submodules_arg(struct diff_options *diffopt,
 293                                   const char *arg)
 294 {
 295         DIFF_OPT_CLR(diffopt, IGNORE_SUBMODULES);
 296         DIFF_OPT_CLR(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 297         DIFF_OPT_CLR(diffopt, IGNORE_DIRTY_SUBMODULES);
 298
 299         if (!strcmp(arg, "all"))
 300                 DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
 301         else if (!strcmp(arg, "untracked"))
 302                 DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 303         else if (!strcmp(arg, "dirty"))
 304                 DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES);
 305         else if (strcmp(arg, "none"))
 306                 die("bad --ignore-submodules argument: %s", arg);
 307 }
 308
 309 static int prepare_submodule_summary(struct rev_info *rev, const char *path,
 310                 struct commit *left, struct commit *right,
 311                 struct commit_list *merge_bases)
 312 {
 313         struct commit_list *list;
 314
 315         init_revisions(rev, NULL);
 316         setup_revisions(0, NULL, rev, NULL);
 317         rev->left_right = 1;
 318         rev->first_parent_only = 1;
 319         left->object.flags |= SYMMETRIC_LEFT;
 320         add_pending_object(rev, &left->object, path);
 321         add_pending_object(rev, &right->object, path);
 322         for (list = merge_bases; list; list = list->next) {
 323                 list->item->object.flags |= UNINTERESTING;
 324                 add_pending_object(rev, &list->item->object,
 325                         oid_to_hex(&list->item->object.oid));
 326         }
 327         return prepare_revision_walk(rev);
 328 }
 329
 330 static void print_submodule_summary(struct rev_info *rev, FILE *f,
 331                 const char *line_prefix,
 332                 const char *del, const char *add, const char *reset)
 333 {
 334         static const char format[] = "  %m %s";
 335         struct strbuf sb = STRBUF_INIT;
 336         struct commit *commit;
 337
 338         while ((commit = get_revision(rev))) {
 339                 struct pretty_print_context ctx = {0};
 340                 ctx.date_mode = rev->date_mode;
 341                 ctx.output_encoding = get_log_output_encoding();
 342                 strbuf_setlen(&sb, 0);
 343                 strbuf_addstr(&sb, line_prefix);
 344                 if (commit->object.flags & SYMMETRIC_LEFT) {
 345                         if (del)
 346                                 strbuf_addstr(&sb, del);
 347                 }
 348                 else if (add)
 349                         strbuf_addstr(&sb, add);
 350                 format_commit_message(commit, format, &sb, &ctx);
 351                 if (reset)
 352                         strbuf_addstr(&sb, reset);
 353                 strbuf_addch(&sb, '\n');
 354                 fprintf(f, "%s", sb.buf);
 355         }
 356         strbuf_release(&sb);
 357 }
 358
 359 static void prepare_submodule_repo_env_no_git_dir(struct argv_array *out)
 360 {
 361         const char * const *var;
 362
 363         for (var = local_repo_env; *var; var++) {
 364                 if (strcmp(*var, CONFIG_DATA_ENVIRONMENT))
 365                         argv_array_push(out, *var);
 366         }
 367 }
 368
 369 void prepare_submodule_repo_env(struct argv_array *out)
 370 {
 371         prepare_submodule_repo_env_no_git_dir(out);
 372         argv_array_pushf(out, "%s=%s", GIT_DIR_ENVIRONMENT,
 373                          DEFAULT_GIT_DIR_ENVIRONMENT);
 374 }
 375
 376 /* Helper function to display the submodule header line prior to the full
 377  * summary output. If it can locate the submodule objects directory it will
 378  * attempt to lookup both the left and right commits and put them into the
 379  * left and right pointers.
 380  */
 381 static void show_submodule_header(FILE *f, const char *path,
 382                 const char *line_prefix,
 383                 struct object_id *one, struct object_id *two,
 384                 unsigned dirty_submodule, const char *meta,
 385                 const char *reset,
 386                 struct commit **left, struct commit **right,
 387                 struct commit_list **merge_bases)
 388 {
 389         const char *message = NULL;
 390         struct strbuf sb = STRBUF_INIT;
 391         int fast_forward = 0, fast_backward = 0;
 392
 393         if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
 394                 fprintf(f, "%sSubmodule %s contains untracked content\n",
 395                         line_prefix, path);
 396         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
 397                 fprintf(f, "%sSubmodule %s contains modified content\n",
 398                         line_prefix, path);
 399
 400         if (is_null_oid(one))
 401                 message = "(new submodule)";
 402         else if (is_null_oid(two))
 403                 message = "(submodule deleted)";
 404
 405         if (add_submodule_odb(path)) {
 406                 if (!message)
 407                         message = "(not initialized)";
 408                 goto output_header;
 409         }
 410
 411         /*
 412          * Attempt to lookup the commit references, and determine if this is
 413          * a fast forward or fast backwards update.
 414          */
 415         *left = lookup_commit_reference(one->hash);
 416         *right = lookup_commit_reference(two->hash);
 417
 418         /*
 419          * Warn about missing commits in the submodule project, but only if
 420          * they aren't null.
 421          */
 422         if ((!is_null_oid(one) && !*left) ||
 423              (!is_null_oid(two) && !*right))
 424                 message = "(commits not present)";
 425
 426         *merge_bases = get_merge_bases(*left, *right);
 427         if (*merge_bases) {
 428                 if ((*merge_bases)->item == *left)
 429                         fast_forward = 1;
 430                 else if ((*merge_bases)->item == *right)
 431                         fast_backward = 1;
 432         }
 433
 434         if (!oidcmp(one, two)) {
 435                 strbuf_release(&sb);
 436                 return;
 437         }
 438
 439 output_header:
 440         strbuf_addf(&sb, "%s%sSubmodule %s ", line_prefix, meta, path);
 441         strbuf_add_unique_abbrev(&sb, one->hash, DEFAULT_ABBREV);
 442         strbuf_addstr(&sb, (fast_backward || fast_forward) ? ".." : "...");
 443         strbuf_add_unique_abbrev(&sb, two->hash, DEFAULT_ABBREV);
 444         if (message)
 445                 strbuf_addf(&sb, " %s%s\n", message, reset);
 446         else
 447                 strbuf_addf(&sb, "%s:%s\n", fast_backward ? " (rewind)" : "", reset);
 448         fwrite(sb.buf, sb.len, 1, f);
 449
 450         strbuf_release(&sb);
 451 }
 452
 453 void show_submodule_summary(FILE *f, const char *path,
 454                 const char *line_prefix,
 455                 struct object_id *one, struct object_id *two,
 456                 unsigned dirty_submodule, const char *meta,
 457                 const char *del, const char *add, const char *reset)
 458 {
 459         struct rev_info rev;
 460         struct commit *left = NULL, *right = NULL;
 461         struct commit_list *merge_bases = NULL;
 462
 463         show_submodule_header(f, path, line_prefix, one, two, dirty_submodule,
 464                               meta, reset, &left, &right, &merge_bases);
 465
 466         /*
 467          * If we don't have both a left and a right pointer, there is no
 468          * reason to try and display a summary. The header line should contain
 469          * all the information the user needs.
 470          */
 471         if (!left || !right)
 472                 goto out;
 473
 474         /* Treat revision walker failure the same as missing commits */
 475         if (prepare_submodule_summary(&rev, path, left, right, merge_bases)) {
 476                 fprintf(f, "%s(revision walker failed)\n", line_prefix);
 477                 goto out;
 478         }
 479
 480         print_submodule_summary(&rev, f, line_prefix, del, add, reset);
 481
 482 out:
 483         if (merge_bases)
 484                 free_commit_list(merge_bases);
 485         clear_commit_marks(left, ~0);
 486         clear_commit_marks(right, ~0);
 487 }
 488
 489 void show_submodule_inline_diff(FILE *f, const char *path,
 490                 const char *line_prefix,
 491                 struct object_id *one, struct object_id *two,
 492                 unsigned dirty_submodule, const char *meta,
 493                 const char *del, const char *add, const char *reset,
 494                 const struct diff_options *o)
 495 {
 496         const struct object_id *old = &empty_tree_oid, *new = &empty_tree_oid;
 497         struct commit *left = NULL, *right = NULL;
 498         struct commit_list *merge_bases = NULL;
 499         struct strbuf submodule_dir = STRBUF_INIT;
 500         struct child_process cp = CHILD_PROCESS_INIT;
 501
 502         show_submodule_header(f, path, line_prefix, one, two, dirty_submodule,
 503                               meta, reset, &left, &right, &merge_bases);
 504
 505         /* We need a valid left and right commit to display a difference */
 506         if (!(left || is_null_oid(one)) ||
 507             !(right || is_null_oid(two)))
 508                 goto done;
 509
 510         if (left)
 511                 old = one;
 512         if (right)
 513                 new = two;
 514
 515         fflush(f);
 516         cp.git_cmd = 1;
 517         cp.dir = path;
 518         cp.out = dup(fileno(f));
 519         cp.no_stdin = 1;
 520
 521         /* TODO: other options may need to be passed here. */
 522         argv_array_push(&cp.args, "diff");
 523         argv_array_pushf(&cp.args, "--line-prefix=%s", line_prefix);
 524         if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
 525                 argv_array_pushf(&cp.args, "--src-prefix=%s%s/",
 526                                  o->b_prefix, path);
 527                 argv_array_pushf(&cp.args, "--dst-prefix=%s%s/",
 528                                  o->a_prefix, path);
 529         } else {
 530                 argv_array_pushf(&cp.args, "--src-prefix=%s%s/",
 531                                  o->a_prefix, path);
 532                 argv_array_pushf(&cp.args, "--dst-prefix=%s%s/",
 533                                  o->b_prefix, path);
 534         }
 535         argv_array_push(&cp.args, oid_to_hex(old));
 536         /*
 537          * If the submodule has modified content, we will diff against the
 538          * work tree, under the assumption that the user has asked for the
 539          * diff format and wishes to actually see all differences even if they
 540          * haven't yet been committed to the submodule yet.
 541          */
 542         if (!(dirty_submodule & DIRTY_SUBMODULE_MODIFIED))
 543                 argv_array_push(&cp.args, oid_to_hex(new));
 544
 545         if (run_command(&cp))
 546                 fprintf(f, "(diff failed)\n");
 547
 548 done:
 549         strbuf_release(&submodule_dir);
 550         if (merge_bases)
 551                 free_commit_list(merge_bases);
 552         if (left)
 553                 clear_commit_marks(left, ~0);
 554         if (right)
 555                 clear_commit_marks(right, ~0);
 556 }
 557
 558 void set_config_fetch_recurse_submodules(int value)
 559 {
 560         config_fetch_recurse_submodules = value;
 561 }
 562
 563 void set_config_update_recurse_submodules(int value)
 564 {
 565         config_update_recurse_submodules = value;
 566 }
 567
 568 int should_update_submodules(void)
 569 {
 570         return config_update_recurse_submodules == RECURSE_SUBMODULES_ON;
 571 }
 572
 573 const struct submodule *submodule_from_ce(const struct cache_entry *ce)
 574 {
 575         if (!S_ISGITLINK(ce->ce_mode))
 576                 return NULL;
 577
 578         if (!should_update_submodules())
 579                 return NULL;
 580
 581         return submodule_from_path(null_sha1, ce->name);
 582 }
 583
 584 static int has_remote(const char *refname, const struct object_id *oid,
 585                       int flags, void *cb_data)
 586 {
 587         return 1;
 588 }
 589
 590 static int append_sha1_to_argv(const unsigned char sha1[20], void *data)
 591 {
 592         struct argv_array *argv = data;
 593         argv_array_push(argv, sha1_to_hex(sha1));
 594         return 0;
 595 }
 596
 597 static int check_has_commit(const unsigned char sha1[20], void *data)
 598 {
 599         int *has_commit = data;
 600
 601         if (!lookup_commit_reference(sha1))
 602                 *has_commit = 0;
 603
 604         return 0;
 605 }
 606
 607 static int submodule_has_commits(const char *path, struct sha1_array *commits)
 608 {
 609         int has_commit = 1;
 610
 611         if (add_submodule_odb(path))
 612                 return 0;
 613
 614         sha1_array_for_each_unique(commits, check_has_commit, &has_commit);
 615         return has_commit;
 616 }
 617
 618 static int submodule_needs_pushing(const char *path, struct sha1_array *commits)
 619 {
 620         if (!submodule_has_commits(path, commits))
 621                 /*
 622                  * NOTE: We do consider it safe to return "no" here. The
 623                  * correct answer would be "We do not know" instead of
 624                  * "No push needed", but it is quite hard to change
 625                  * the submodule pointer without having the submodule
 626                  * around. If a user did however change the submodules
 627                  * without having the submodule around, this indicates
 628                  * an expert who knows what they are doing or a
 629                  * maintainer integrating work from other people. In
 630                  * both cases it should be safe to skip this check.
 631                  */
 632                 return 0;
 633
 634         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 635                 struct child_process cp = CHILD_PROCESS_INIT;
 636                 struct strbuf buf = STRBUF_INIT;
 637                 int needs_pushing = 0;
 638
 639                 argv_array_push(&cp.args, "rev-list");
 640                 sha1_array_for_each_unique(commits, append_sha1_to_argv, &cp.args);
 641                 argv_array_pushl(&cp.args, "--not", "--remotes", "-n", "1" , NULL);
 642
 643                 prepare_submodule_repo_env(&cp.env_array);
 644                 cp.git_cmd = 1;
 645                 cp.no_stdin = 1;
 646                 cp.out = -1;
 647                 cp.dir = path;
 648                 if (start_command(&cp))
 649                         die("Could not run 'git rev-list <commits> --not --remotes -n 1' command in submodule %s",
 650                                         path);
 651                 if (strbuf_read(&buf, cp.out, 41))
 652                         needs_pushing = 1;
 653                 finish_command(&cp);
 654                 close(cp.out);
 655                 strbuf_release(&buf);
 656                 return needs_pushing;
 657         }
 658
 659         return 0;
 660 }
 661
 662 static struct sha1_array *submodule_commits(struct string_list *submodules,
 663                                             const char *path)
 664 {
 665         struct string_list_item *item;
 666
 667         item = string_list_insert(submodules, path);
 668         if (item->util)
 669                 return (struct sha1_array *) item->util;
 670
 671         /* NEEDSWORK: should we have sha1_array_init()? */
 672         item->util = xcalloc(1, sizeof(struct sha1_array));
 673         return (struct sha1_array *) item->util;
 674 }
 675
 676 static void collect_submodules_from_diff(struct diff_queue_struct *q,
 677                                          struct diff_options *options,
 678                                          void *data)
 679 {
 680         int i;
 681         struct string_list *submodules = data;
 682
 683         for (i = 0; i < q->nr; i++) {
 684                 struct diff_filepair *p = q->queue[i];
 685                 struct sha1_array *commits;
 686                 if (!S_ISGITLINK(p->two->mode))
 687                         continue;
 688                 commits = submodule_commits(submodules, p->two->path);
 689                 sha1_array_append(commits, p->two->oid.hash);
 690         }
 691 }
 692
 693 static void find_unpushed_submodule_commits(struct commit *commit,
 694                 struct string_list *needs_pushing)
 695 {
 696         struct rev_info rev;
 697
 698         init_revisions(&rev, NULL);
 699         rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
 700         rev.diffopt.format_callback = collect_submodules_from_diff;
 701         rev.diffopt.format_callback_data = needs_pushing;
 702         diff_tree_combined_merge(commit, 1, &rev);
 703 }
 704
 705 static void free_submodules_sha1s(struct string_list *submodules)
 706 {
 707         struct string_list_item *item;
 708         for_each_string_list_item(item, submodules)
 709                 sha1_array_clear((struct sha1_array *) item->util);
 710         string_list_clear(submodules, 1);
 711 }
 712
 713 int find_unpushed_submodules(struct sha1_array *commits,
 714                 const char *remotes_name, struct string_list *needs_pushing)
 715 {
 716         struct rev_info rev;
 717         struct commit *commit;
 718         struct string_list submodules = STRING_LIST_INIT_DUP;
 719         struct string_list_item *submodule;
 720         struct argv_array argv = ARGV_ARRAY_INIT;
 721
 722         init_revisions(&rev, NULL);
 723
 724         /* argv.argv[0] will be ignored by setup_revisions */
 725         argv_array_push(&argv, "find_unpushed_submodules");
 726         sha1_array_for_each_unique(commits, append_sha1_to_argv, &argv);
 727         argv_array_push(&argv, "--not");
 728         argv_array_pushf(&argv, "--remotes=%s", remotes_name);
 729
 730         setup_revisions(argv.argc, argv.argv, &rev, NULL);
 731         if (prepare_revision_walk(&rev))
 732                 die("revision walk setup failed");
 733
 734         while ((commit = get_revision(&rev)) != NULL)
 735                 find_unpushed_submodule_commits(commit, &submodules);
 736
 737         reset_revision_walk();
 738         argv_array_clear(&argv);
 739
 740         for_each_string_list_item(submodule, &submodules) {
 741                 struct sha1_array *commits = (struct sha1_array *) submodule->util;
 742
 743                 if (submodule_needs_pushing(submodule->string, commits))
 744                         string_list_insert(needs_pushing, submodule->string);
 745         }
 746         free_submodules_sha1s(&submodules);
 747
 748         return needs_pushing->nr;
 749 }
 750
 751 static int push_submodule(const char *path, int dry_run)
 752 {
 753         if (add_submodule_odb(path))
 754                 return 1;
 755
 756         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 757                 struct child_process cp = CHILD_PROCESS_INIT;
 758                 argv_array_push(&cp.args, "push");
 759                 if (dry_run)
 760                         argv_array_push(&cp.args, "--dry-run");
 761
 762                 prepare_submodule_repo_env(&cp.env_array);
 763                 cp.git_cmd = 1;
 764                 cp.no_stdin = 1;
 765                 cp.dir = path;
 766                 if (run_command(&cp))
 767                         return 0;
 768                 close(cp.out);
 769         }
 770
 771         return 1;
 772 }
 773
 774 int push_unpushed_submodules(struct sha1_array *commits,
 775                              const char *remotes_name,
 776                              int dry_run)
 777 {
 778         int i, ret = 1;
 779         struct string_list needs_pushing = STRING_LIST_INIT_DUP;
 780
 781         if (!find_unpushed_submodules(commits, remotes_name, &needs_pushing))
 782                 return 1;
 783
 784         for (i = 0; i < needs_pushing.nr; i++) {
 785                 const char *path = needs_pushing.items[i].string;
 786                 fprintf(stderr, "Pushing submodule '%s'\n", path);
 787                 if (!push_submodule(path, dry_run)) {
 788                         fprintf(stderr, "Unable to push submodule '%s'\n", path);
 789                         ret = 0;
 790                 }
 791         }
 792
 793         string_list_clear(&needs_pushing, 0);
 794
 795         return ret;
 796 }
 797
 798 static int is_submodule_commit_present(const char *path, unsigned char sha1[20])
 799 {
 800         int is_present = 0;
 801         if (!add_submodule_odb(path) && lookup_commit_reference(sha1)) {
 802                 /* Even if the submodule is checked out and the commit is
 803                  * present, make sure it is reachable from a ref. */
 804                 struct child_process cp = CHILD_PROCESS_INIT;
 805                 const char *argv[] = {"rev-list", "-n", "1", NULL, "--not", "--all", NULL};
 806                 struct strbuf buf = STRBUF_INIT;
 807
 808                 argv[3] = sha1_to_hex(sha1);
 809                 cp.argv = argv;
 810                 prepare_submodule_repo_env(&cp.env_array);
 811                 cp.git_cmd = 1;
 812                 cp.no_stdin = 1;
 813                 cp.dir = path;
 814                 if (!capture_command(&cp, &buf, 1024) && !buf.len)
 815                         is_present = 1;
 816
 817                 strbuf_release(&buf);
 818         }
 819         return is_present;
 820 }
 821
 822 static void submodule_collect_changed_cb(struct diff_queue_struct *q,
 823                                          struct diff_options *options,
 824                                          void *data)
 825 {
 826         int i;
 827         for (i = 0; i < q->nr; i++) {
 828                 struct diff_filepair *p = q->queue[i];
 829                 if (!S_ISGITLINK(p->two->mode))
 830                         continue;
 831
 832                 if (S_ISGITLINK(p->one->mode)) {
 833                         /* NEEDSWORK: We should honor the name configured in
 834                          * the .gitmodules file of the commit we are examining
 835                          * here to be able to correctly follow submodules
 836                          * being moved around. */
 837                         struct string_list_item *path;
 838                         path = unsorted_string_list_lookup(&changed_submodule_paths, p->two->path);
 839                         if (!path && !is_submodule_commit_present(p->two->path, p->two->oid.hash))
 840                                 string_list_append(&changed_submodule_paths, xstrdup(p->two->path));
 841                 } else {
 842                         /* Submodule is new or was moved here */
 843                         /* NEEDSWORK: When the .git directories of submodules
 844                          * live inside the superprojects .git directory some
 845                          * day we should fetch new submodules directly into
 846                          * that location too when config or options request
 847                          * that so they can be checked out from there. */
 848                         continue;
 849                 }
 850         }
 851 }
 852
 853 static int add_sha1_to_array(const char *ref, const struct object_id *oid,
 854                              int flags, void *data)
 855 {
 856         sha1_array_append(data, oid->hash);
 857         return 0;
 858 }
 859
 860 void check_for_new_submodule_commits(unsigned char new_sha1[20])
 861 {
 862         if (!initialized_fetch_ref_tips) {
 863                 for_each_ref(add_sha1_to_array, &ref_tips_before_fetch);
 864                 initialized_fetch_ref_tips = 1;
 865         }
 866
 867         sha1_array_append(&ref_tips_after_fetch, new_sha1);
 868 }
 869
 870 static int add_sha1_to_argv(const unsigned char sha1[20], void *data)
 871 {
 872         argv_array_push(data, sha1_to_hex(sha1));
 873         return 0;
 874 }
 875
 876 static void calculate_changed_submodule_paths(void)
 877 {
 878         struct rev_info rev;
 879         struct commit *commit;
 880         struct argv_array argv = ARGV_ARRAY_INIT;
 881
 882         /* No need to check if there are no submodules configured */
 883         if (!submodule_from_path(NULL, NULL))
 884                 return;
 885
 886         init_revisions(&rev, NULL);
 887         argv_array_push(&argv, "--"); /* argv[0] program name */
 888         sha1_array_for_each_unique(&ref_tips_after_fetch,
 889                                    add_sha1_to_argv, &argv);
 890         argv_array_push(&argv, "--not");
 891         sha1_array_for_each_unique(&ref_tips_before_fetch,
 892                                    add_sha1_to_argv, &argv);
 893         setup_revisions(argv.argc, argv.argv, &rev, NULL);
 894         if (prepare_revision_walk(&rev))
 895                 die("revision walk setup failed");
 896
 897         /*
 898          * Collect all submodules (whether checked out or not) for which new
 899          * commits have been recorded upstream in "changed_submodule_paths".
 900          */
 901         while ((commit = get_revision(&rev))) {
 902                 struct commit_list *parent = commit->parents;
 903                 while (parent) {
 904                         struct diff_options diff_opts;
 905                         diff_setup(&diff_opts);
 906                         DIFF_OPT_SET(&diff_opts, RECURSIVE);
 907                         diff_opts.output_format |= DIFF_FORMAT_CALLBACK;
 908                         diff_opts.format_callback = submodule_collect_changed_cb;
 909                         diff_setup_done(&diff_opts);
 910                         diff_tree_sha1(parent->item->object.oid.hash, commit->object.oid.hash, "", &diff_opts);
 911                         diffcore_std(&diff_opts);
 912                         diff_flush(&diff_opts);
 913                         parent = parent->next;
 914                 }
 915         }
 916
 917         argv_array_clear(&argv);
 918         sha1_array_clear(&ref_tips_before_fetch);
 919         sha1_array_clear(&ref_tips_after_fetch);
 920         initialized_fetch_ref_tips = 0;
 921 }
 922
 923 struct submodule_parallel_fetch {
 924         int count;
 925         struct argv_array args;
 926         const char *work_tree;
 927         const char *prefix;
 928         int command_line_option;
 929         int quiet;
 930         int result;
 931 };
 932 #define SPF_INIT {0, ARGV_ARRAY_INIT, NULL, NULL, 0, 0, 0}
 933
 934 static int get_next_submodule(struct child_process *cp,
 935                               struct strbuf *err, void *data, void **task_cb)
 936 {
 937         int ret = 0;
 938         struct submodule_parallel_fetch *spf = data;
 939
 940         for (; spf->count < active_nr; spf->count++) {
 941                 struct strbuf submodule_path = STRBUF_INIT;
 942                 struct strbuf submodule_git_dir = STRBUF_INIT;
 943                 struct strbuf submodule_prefix = STRBUF_INIT;
 944                 const struct cache_entry *ce = active_cache[spf->count];
 945                 const char *git_dir, *default_argv;
 946                 const struct submodule *submodule;
 947
 948                 if (!S_ISGITLINK(ce->ce_mode))
 949                         continue;
 950
 951                 submodule = submodule_from_path(null_sha1, ce->name);
 952                 if (!submodule)
 953                         submodule = submodule_from_name(null_sha1, ce->name);
 954
 955                 default_argv = "yes";
 956                 if (spf->command_line_option == RECURSE_SUBMODULES_DEFAULT) {
 957                         if (submodule &&
 958                             submodule->fetch_recurse !=
 959                                                 RECURSE_SUBMODULES_NONE) {
 960                                 if (submodule->fetch_recurse ==
 961                                                 RECURSE_SUBMODULES_OFF)
 962                                         continue;
 963                                 if (submodule->fetch_recurse ==
 964                                                 RECURSE_SUBMODULES_ON_DEMAND) {
 965                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 966                                                 continue;
 967                                         default_argv = "on-demand";
 968                                 }
 969                         } else {
 970                                 if ((config_fetch_recurse_submodules == RECURSE_SUBMODULES_OFF) ||
 971                                     gitmodules_is_unmerged)
 972                                         continue;
 973                                 if (config_fetch_recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) {
 974                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 975                                                 continue;
 976                                         default_argv = "on-demand";
 977                                 }
 978                         }
 979                 } else if (spf->command_line_option == RECURSE_SUBMODULES_ON_DEMAND) {
 980                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 981                                 continue;
 982                         default_argv = "on-demand";
 983                 }
 984
 985                 strbuf_addf(&submodule_path, "%s/%s", spf->work_tree, ce->name);
 986                 strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
 987                 strbuf_addf(&submodule_prefix, "%s%s/", spf->prefix, ce->name);
 988                 git_dir = read_gitfile(submodule_git_dir.buf);
 989                 if (!git_dir)
 990                         git_dir = submodule_git_dir.buf;
 991                 if (is_directory(git_dir)) {
 992                         child_process_init(cp);
 993                         cp->dir = strbuf_detach(&submodule_path, NULL);
 994                         prepare_submodule_repo_env(&cp->env_array);
 995                         cp->git_cmd = 1;
 996                         if (!spf->quiet)
 997                                 strbuf_addf(err, "Fetching submodule %s%s\n",
 998                                             spf->prefix, ce->name);
 999                         argv_array_init(&cp->args);
1000                         argv_array_pushv(&cp->args, spf->args.argv);
1001                         argv_array_push(&cp->args, default_argv);
1002                         argv_array_push(&cp->args, "--submodule-prefix");
1003                         argv_array_push(&cp->args, submodule_prefix.buf);
1004                         ret = 1;
1005                 }
1006                 strbuf_release(&submodule_path);
1007                 strbuf_release(&submodule_git_dir);
1008                 strbuf_release(&submodule_prefix);
1009                 if (ret) {
1010                         spf->count++;
1011                         return 1;
1012                 }
1013         }
1014         return 0;
1015 }
1016
1017 static int fetch_start_failure(struct strbuf *err,
1018                                void *cb, void *task_cb)
1019 {
1020         struct submodule_parallel_fetch *spf = cb;
1021
1022         spf->result = 1;
1023
1024         return 0;
1025 }
1026
1027 static int fetch_finish(int retvalue, struct strbuf *err,
1028                         void *cb, void *task_cb)
1029 {
1030         struct submodule_parallel_fetch *spf = cb;
1031
1032         if (retvalue)
1033                 spf->result = 1;
1034
1035         return 0;
1036 }
1037
1038 int fetch_populated_submodules(const struct argv_array *options,
1039                                const char *prefix, int command_line_option,
1040                                int quiet, int max_parallel_jobs)
1041 {
1042         int i;
1043         struct submodule_parallel_fetch spf = SPF_INIT;
1044
1045         spf.work_tree = get_git_work_tree();
1046         spf.command_line_option = command_line_option;
1047         spf.quiet = quiet;
1048         spf.prefix = prefix;
1049
1050         if (!spf.work_tree)
1051                 goto out;
1052
1053         if (read_cache() < 0)
1054                 die("index file corrupt");
1055
1056         argv_array_push(&spf.args, "fetch");
1057         for (i = 0; i < options->argc; i++)
1058                 argv_array_push(&spf.args, options->argv[i]);
1059         argv_array_push(&spf.args, "--recurse-submodules-default");
1060         /* default value, "--submodule-prefix" and its value are added later */
1061
1062         if (max_parallel_jobs < 0)
1063                 max_parallel_jobs = parallel_jobs;
1064
1065         calculate_changed_submodule_paths();
1066         run_processes_parallel(max_parallel_jobs,
1067                                get_next_submodule,
1068                                fetch_start_failure,
1069                                fetch_finish,
1070                                &spf);
1071
1072         argv_array_clear(&spf.args);
1073 out:
1074         string_list_clear(&changed_submodule_paths, 1);
1075         return spf.result;
1076 }
1077
1078 unsigned is_submodule_modified(const char *path, int ignore_untracked)
1079 {
1080         ssize_t len;
1081         struct child_process cp = CHILD_PROCESS_INIT;
1082         const char *argv[] = {
1083                 "status",
1084                 "--porcelain",
1085                 NULL,
1086                 NULL,
1087         };
1088         struct strbuf buf = STRBUF_INIT;
1089         unsigned dirty_submodule = 0;
1090         const char *line, *next_line;
1091         const char *git_dir;
1092
1093         strbuf_addf(&buf, "%s/.git", path);
1094         git_dir = read_gitfile(buf.buf);
1095         if (!git_dir)
1096                 git_dir = buf.buf;
1097         if (!is_directory(git_dir)) {
1098                 strbuf_release(&buf);
1099                 /* The submodule is not checked out, so it is not modified */
1100                 return 0;
1101
1102         }
1103         strbuf_reset(&buf);
1104
1105         if (ignore_untracked)
1106                 argv[2] = "-uno";
1107
1108         cp.argv = argv;
1109         prepare_submodule_repo_env(&cp.env_array);
1110         cp.git_cmd = 1;
1111         cp.no_stdin = 1;
1112         cp.out = -1;
1113         cp.dir = path;
1114         if (start_command(&cp))
1115                 die("Could not run 'git status --porcelain' in submodule %s", path);
1116
1117         len = strbuf_read(&buf, cp.out, 1024);
1118         line = buf.buf;
1119         while (len > 2) {
1120                 if ((line[0] == '?') && (line[1] == '?')) {
1121                         dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
1122                         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
1123                                 break;
1124                 } else {
1125                         dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
1126                         if (ignore_untracked ||
1127                             (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED))
1128                                 break;
1129                 }
1130                 next_line = strchr(line, '\n');
1131                 if (!next_line)
1132                         break;
1133                 next_line++;
1134                 len -= (next_line - line);
1135                 line = next_line;
1136         }
1137         close(cp.out);
1138
1139         if (finish_command(&cp))
1140                 die("'git status --porcelain' failed in submodule %s", path);
1141
1142         strbuf_release(&buf);
1143         return dirty_submodule;
1144 }
1145
1146 int submodule_uses_gitfile(const char *path)
1147 {
1148         struct child_process cp = CHILD_PROCESS_INIT;
1149         const char *argv[] = {
1150                 "submodule",
1151                 "foreach",
1152                 "--quiet",
1153                 "--recursive",
1154                 "test -f .git",
1155                 NULL,
1156         };
1157         struct strbuf buf = STRBUF_INIT;
1158         const char *git_dir;
1159
1160         strbuf_addf(&buf, "%s/.git", path);
1161         git_dir = read_gitfile(buf.buf);
1162         if (!git_dir) {
1163                 strbuf_release(&buf);
1164                 return 0;
1165         }
1166         strbuf_release(&buf);
1167
1168         /* Now test that all nested submodules use a gitfile too */
1169         cp.argv = argv;
1170         prepare_submodule_repo_env(&cp.env_array);
1171         cp.git_cmd = 1;
1172         cp.no_stdin = 1;
1173         cp.no_stderr = 1;
1174         cp.no_stdout = 1;
1175         cp.dir = path;
1176         if (run_command(&cp))
1177                 return 0;
1178
1179         return 1;
1180 }
1181
1182 /*
1183  * Check if it is a bad idea to remove a submodule, i.e. if we'd lose data
1184  * when doing so.
1185  *
1186  * Return 1 if we'd lose data, return 0 if the removal is fine,
1187  * and negative values for errors.
1188  */
1189 int bad_to_remove_submodule(const char *path, unsigned flags)
1190 {
1191         ssize_t len;
1192         struct child_process cp = CHILD_PROCESS_INIT;
1193         struct strbuf buf = STRBUF_INIT;
1194         int ret = 0;
1195
1196         if (!file_exists(path) || is_empty_dir(path))
1197                 return 0;
1198
1199         if (!submodule_uses_gitfile(path))
1200                 return 1;
1201
1202         argv_array_pushl(&cp.args, "status", "--porcelain",
1203                                    "--ignore-submodules=none", NULL);
1204
1205         if (flags & SUBMODULE_REMOVAL_IGNORE_UNTRACKED)
1206                 argv_array_push(&cp.args, "-uno");
1207         else
1208                 argv_array_push(&cp.args, "-uall");
1209
1210         if (!(flags & SUBMODULE_REMOVAL_IGNORE_IGNORED_UNTRACKED))
1211                 argv_array_push(&cp.args, "--ignored");
1212
1213         prepare_submodule_repo_env(&cp.env_array);
1214         cp.git_cmd = 1;
1215         cp.no_stdin = 1;
1216         cp.out = -1;
1217         cp.dir = path;
1218         if (start_command(&cp)) {
1219                 if (flags & SUBMODULE_REMOVAL_DIE_ON_ERROR)
1220                         die(_("could not start 'git status in submodule '%s'"),
1221                                 path);
1222                 ret = -1;
1223                 goto out;
1224         }
1225
1226         len = strbuf_read(&buf, cp.out, 1024);
1227         if (len > 2)
1228                 ret = 1;
1229         close(cp.out);
1230
1231         if (finish_command(&cp)) {
1232                 if (flags & SUBMODULE_REMOVAL_DIE_ON_ERROR)
1233                         die(_("could not run 'git status in submodule '%s'"),
1234                                 path);
1235                 ret = -1;
1236         }
1237 out:
1238         strbuf_release(&buf);
1239         return ret;
1240 }
1241
1242 static const char *get_super_prefix_or_empty(void)
1243 {
1244         const char *s = get_super_prefix();
1245         if (!s)
1246                 s = "";
1247         return s;
1248 }
1249
1250 static int submodule_has_dirty_index(const struct submodule *sub)
1251 {
1252         struct child_process cp = CHILD_PROCESS_INIT;
1253
1254         prepare_submodule_repo_env_no_git_dir(&cp.env_array);
1255
1256         cp.git_cmd = 1;
1257         argv_array_pushl(&cp.args, "diff-index", "--quiet",
1258                                    "--cached", "HEAD", NULL);
1259         cp.no_stdin = 1;
1260         cp.no_stdout = 1;
1261         cp.dir = sub->path;
1262         if (start_command(&cp))
1263                 die("could not recurse into submodule '%s'", sub->path);
1264
1265         return finish_command(&cp);
1266 }
1267
1268 static void submodule_reset_index(const char *path)
1269 {
1270         struct child_process cp = CHILD_PROCESS_INIT;
1271         prepare_submodule_repo_env_no_git_dir(&cp.env_array);
1272
1273         cp.git_cmd = 1;
1274         cp.no_stdin = 1;
1275         cp.dir = path;
1276
1277         argv_array_pushf(&cp.args, "--super-prefix=%s%s/",
1278                                    get_super_prefix_or_empty(), path);
1279         argv_array_pushl(&cp.args, "read-tree", "-u", "--reset", NULL);
1280
1281         argv_array_push(&cp.args, EMPTY_TREE_SHA1_HEX);
1282
1283         if (run_command(&cp))
1284                 die("could not reset submodule index");
1285 }
1286
1287 /**
1288  * Moves a submodule at a given path from a given head to another new head.
1289  * For edge cases (a submodule coming into existence or removing a submodule)
1290  * pass NULL for old or new respectively.
1291  */
1292 int submodule_move_head(const char *path,
1293                          const char *old,
1294                          const char *new,
1295                          unsigned flags)
1296 {
1297         int ret = 0;
1298         struct child_process cp = CHILD_PROCESS_INIT;
1299         const struct submodule *sub;
1300
1301         sub = submodule_from_path(null_sha1, path);
1302
1303         if (!sub)
1304                 die("BUG: could not get submodule information for '%s'", path);
1305
1306         if (old && !(flags & SUBMODULE_MOVE_HEAD_FORCE)) {
1307                 /* Check if the submodule has a dirty index. */
1308                 if (submodule_has_dirty_index(sub))
1309                         return error(_("submodule '%s' has dirty index"), path);
1310         }
1311
1312         if (!(flags & SUBMODULE_MOVE_HEAD_DRY_RUN)) {
1313                 if (old) {
1314                         if (!submodule_uses_gitfile(path))
1315                                 absorb_git_dir_into_superproject("", path,
1316                                         ABSORB_GITDIR_RECURSE_SUBMODULES);
1317                 } else {
1318                         struct strbuf sb = STRBUF_INIT;
1319                         strbuf_addf(&sb, "%s/modules/%s",
1320                                     get_git_common_dir(), sub->name);
1321                         connect_work_tree_and_git_dir(path, sb.buf);
1322                         strbuf_release(&sb);
1323
1324                         /* make sure the index is clean as well */
1325                         submodule_reset_index(path);
1326                 }
1327         }
1328
1329         prepare_submodule_repo_env_no_git_dir(&cp.env_array);
1330
1331         cp.git_cmd = 1;
1332         cp.no_stdin = 1;
1333         cp.dir = path;
1334
1335         argv_array_pushf(&cp.args, "--super-prefix=%s%s/",
1336                         get_super_prefix_or_empty(), path);
1337         argv_array_pushl(&cp.args, "read-tree", NULL);
1338
1339         if (flags & SUBMODULE_MOVE_HEAD_DRY_RUN)
1340                 argv_array_push(&cp.args, "-n");
1341         else
1342                 argv_array_push(&cp.args, "-u");
1343
1344         if (flags & SUBMODULE_MOVE_HEAD_FORCE)
1345                 argv_array_push(&cp.args, "--reset");
1346         else
1347                 argv_array_push(&cp.args, "-m");
1348
1349         argv_array_push(&cp.args, old ? old : EMPTY_TREE_SHA1_HEX);
1350         argv_array_push(&cp.args, new ? new : EMPTY_TREE_SHA1_HEX);
1351
1352         if (run_command(&cp)) {
1353                 ret = -1;
1354                 goto out;
1355         }
1356
1357         if (!(flags & SUBMODULE_MOVE_HEAD_DRY_RUN)) {
1358                 if (new) {
1359                         struct child_process cp1 = CHILD_PROCESS_INIT;
1360                         /* also set the HEAD accordingly */
1361                         cp1.git_cmd = 1;
1362                         cp1.no_stdin = 1;
1363                         cp1.dir = path;
1364
1365                         argv_array_pushl(&cp1.args, "update-ref", "HEAD",
1366                                          new ? new : EMPTY_TREE_SHA1_HEX, NULL);
1367
1368                         if (run_command(&cp1)) {
1369                                 ret = -1;
1370                                 goto out;
1371                         }
1372                 } else {
1373                         struct strbuf sb = STRBUF_INIT;
1374
1375                         strbuf_addf(&sb, "%s/.git", path);
1376                         unlink_or_warn(sb.buf);
1377                         strbuf_release(&sb);
1378
1379                         if (is_empty_dir(path))
1380                                 rmdir_or_warn(path);
1381                 }
1382         }
1383 out:
1384         return ret;
1385 }
1386
1387 static int find_first_merges(struct object_array *result, const char *path,
1388                 struct commit *a, struct commit *b)
1389 {
1390         int i, j;
1391         struct object_array merges = OBJECT_ARRAY_INIT;
1392         struct commit *commit;
1393         int contains_another;
1394
1395         char merged_revision[42];
1396         const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
1397                                    "--all", merged_revision, NULL };
1398         struct rev_info revs;
1399         struct setup_revision_opt rev_opts;
1400
1401         memset(result, 0, sizeof(struct object_array));
1402         memset(&rev_opts, 0, sizeof(rev_opts));
1403
1404         /* get all revisions that merge commit a */
1405         snprintf(merged_revision, sizeof(merged_revision), "^%s",
1406                         oid_to_hex(&a->object.oid));
1407         init_revisions(&revs, NULL);
1408         rev_opts.submodule = path;
1409         setup_revisions(ARRAY_SIZE(rev_args)-1, rev_args, &revs, &rev_opts);
1410
1411         /* save all revisions from the above list that contain b */
1412         if (prepare_revision_walk(&revs))
1413                 die("revision walk setup failed");
1414         while ((commit = get_revision(&revs)) != NULL) {
1415                 struct object *o = &(commit->object);
1416                 if (in_merge_bases(b, commit))
1417                         add_object_array(o, NULL, &merges);
1418         }
1419         reset_revision_walk();
1420
1421         /* Now we've got all merges that contain a and b. Prune all
1422          * merges that contain another found merge and save them in
1423          * result.
1424          */
1425         for (i = 0; i < merges.nr; i++) {
1426                 struct commit *m1 = (struct commit *) merges.objects[i].item;
1427
1428                 contains_another = 0;
1429                 for (j = 0; j < merges.nr; j++) {
1430                         struct commit *m2 = (struct commit *) merges.objects[j].item;
1431                         if (i != j && in_merge_bases(m2, m1)) {
1432                                 contains_another = 1;
1433                                 break;
1434                         }
1435                 }
1436
1437                 if (!contains_another)
1438                         add_object_array(merges.objects[i].item, NULL, result);
1439         }
1440
1441         free(merges.objects);
1442         return result->nr;
1443 }
1444
1445 static void print_commit(struct commit *commit)
1446 {
1447         struct strbuf sb = STRBUF_INIT;
1448         struct pretty_print_context ctx = {0};
1449         ctx.date_mode.type = DATE_NORMAL;
1450         format_commit_message(commit, " %h: %m %s", &sb, &ctx);
1451         fprintf(stderr, "%s\n", sb.buf);
1452         strbuf_release(&sb);
1453 }
1454
1455 #define MERGE_WARNING(path, msg) \
1456         warning("Failed to merge submodule %s (%s)", path, msg);
1457
1458 int merge_submodule(unsigned char result[20], const char *path,
1459                     const unsigned char base[20], const unsigned char a[20],
1460                     const unsigned char b[20], int search)
1461 {
1462         struct commit *commit_base, *commit_a, *commit_b;
1463         int parent_count;
1464         struct object_array merges;
1465
1466         int i;
1467
1468         /* store a in result in case we fail */
1469         hashcpy(result, a);
1470
1471         /* we can not handle deletion conflicts */
1472         if (is_null_sha1(base))
1473                 return 0;
1474         if (is_null_sha1(a))
1475                 return 0;
1476         if (is_null_sha1(b))
1477                 return 0;
1478
1479         if (add_submodule_odb(path)) {
1480                 MERGE_WARNING(path, "not checked out");
1481                 return 0;
1482         }
1483
1484         if (!(commit_base = lookup_commit_reference(base)) ||
1485             !(commit_a = lookup_commit_reference(a)) ||
1486             !(commit_b = lookup_commit_reference(b))) {
1487                 MERGE_WARNING(path, "commits not present");
1488                 return 0;
1489         }
1490
1491         /* check whether both changes are forward */
1492         if (!in_merge_bases(commit_base, commit_a) ||
1493             !in_merge_bases(commit_base, commit_b)) {
1494                 MERGE_WARNING(path, "commits don't follow merge-base");
1495                 return 0;
1496         }
1497
1498         /* Case #1: a is contained in b or vice versa */
1499         if (in_merge_bases(commit_a, commit_b)) {
1500                 hashcpy(result, b);
1501                 return 1;
1502         }
1503         if (in_merge_bases(commit_b, commit_a)) {
1504                 hashcpy(result, a);
1505                 return 1;
1506         }
1507
1508         /*
1509          * Case #2: There are one or more merges that contain a and b in
1510          * the submodule. If there is only one, then present it as a
1511          * suggestion to the user, but leave it marked unmerged so the
1512          * user needs to confirm the resolution.
1513          */
1514
1515         /* Skip the search if makes no sense to the calling context.  */
1516         if (!search)
1517                 return 0;
1518
1519         /* find commit which merges them */
1520         parent_count = find_first_merges(&merges, path, commit_a, commit_b);
1521         switch (parent_count) {
1522         case 0:
1523                 MERGE_WARNING(path, "merge following commits not found");
1524                 break;
1525
1526         case 1:
1527                 MERGE_WARNING(path, "not fast-forward");
1528                 fprintf(stderr, "Found a possible merge resolution "
1529                                 "for the submodule:\n");
1530                 print_commit((struct commit *) merges.objects[0].item);
1531                 fprintf(stderr,
1532                         "If this is correct simply add it to the index "
1533                         "for example\n"
1534                         "by using:\n\n"
1535                         "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1536                         "which will accept this suggestion.\n",
1537                         oid_to_hex(&merges.objects[0].item->oid), path);
1538                 break;
1539
1540         default:
1541                 MERGE_WARNING(path, "multiple merges found");
1542                 for (i = 0; i < merges.nr; i++)
1543                         print_commit((struct commit *) merges.objects[i].item);
1544         }
1545
1546         free(merges.objects);
1547         return 0;
1548 }
1549
1550 int parallel_submodules(void)
1551 {
1552         return parallel_jobs;
1553 }
1554
1555 /*
1556  * Embeds a single submodules git directory into the superprojects git dir,
1557  * non recursively.
1558  */
1559 static void relocate_single_git_dir_into_superproject(const char *prefix,
1560                                                       const char *path)
1561 {
1562         char *old_git_dir = NULL, *real_old_git_dir = NULL, *real_new_git_dir = NULL;
1563         const char *new_git_dir;
1564         const struct submodule *sub;
1565
1566         if (submodule_uses_worktrees(path))
1567                 die(_("relocate_gitdir for submodule '%s' with "
1568                       "more than one worktree not supported"), path);
1569
1570         old_git_dir = xstrfmt("%s/.git", path);
1571         if (read_gitfile(old_git_dir))
1572                 /* If it is an actual gitfile, it doesn't need migration. */
1573                 return;
1574
1575         real_old_git_dir = real_pathdup(old_git_dir, 1);
1576
1577         sub = submodule_from_path(null_sha1, path);
1578         if (!sub)
1579                 die(_("could not lookup name for submodule '%s'"), path);
1580
1581         new_git_dir = git_path("modules/%s", sub->name);
1582         if (safe_create_leading_directories_const(new_git_dir) < 0)
1583                 die(_("could not create directory '%s'"), new_git_dir);
1584         real_new_git_dir = real_pathdup(new_git_dir, 1);
1585
1586         fprintf(stderr, _("Migrating git directory of '%s%s' from\n'%s' to\n'%s'\n"),
1587                 get_super_prefix_or_empty(), path,
1588                 real_old_git_dir, real_new_git_dir);
1589
1590         relocate_gitdir(path, real_old_git_dir, real_new_git_dir);
1591
1592         free(old_git_dir);
1593         free(real_old_git_dir);
1594         free(real_new_git_dir);
1595 }
1596
1597 /*
1598  * Migrate the git directory of the submodule given by path from
1599  * having its git directory within the working tree to the git dir nested
1600  * in its superprojects git dir under modules/.
1601  */
1602 void absorb_git_dir_into_superproject(const char *prefix,
1603                                       const char *path,
1604                                       unsigned flags)
1605 {
1606         int err_code;
1607         const char *sub_git_dir;
1608         struct strbuf gitdir = STRBUF_INIT;
1609         strbuf_addf(&gitdir, "%s/.git", path);
1610         sub_git_dir = resolve_gitdir_gently(gitdir.buf, &err_code);
1611
1612         /* Not populated? */
1613         if (!sub_git_dir) {
1614                 const struct submodule *sub;
1615
1616                 if (err_code == READ_GITFILE_ERR_STAT_FAILED) {
1617                         /* unpopulated as expected */
1618                         strbuf_release(&gitdir);
1619                         return;
1620                 }
1621
1622                 if (err_code != READ_GITFILE_ERR_NOT_A_REPO)
1623                         /* We don't know what broke here. */
1624                         read_gitfile_error_die(err_code, path, NULL);
1625
1626                 /*
1627                 * Maybe populated, but no git directory was found?
1628                 * This can happen if the superproject is a submodule
1629                 * itself and was just absorbed. The absorption of the
1630                 * superproject did not rewrite the git file links yet,
1631                 * fix it now.
1632                 */
1633                 sub = submodule_from_path(null_sha1, path);
1634                 if (!sub)
1635                         die(_("could not lookup name for submodule '%s'"), path);
1636                 connect_work_tree_and_git_dir(path,
1637                         git_path("modules/%s", sub->name));
1638         } else {
1639                 /* Is it already absorbed into the superprojects git dir? */
1640                 char *real_sub_git_dir = real_pathdup(sub_git_dir, 1);
1641                 char *real_common_git_dir = real_pathdup(get_git_common_dir(), 1);
1642
1643                 if (!starts_with(real_sub_git_dir, real_common_git_dir))
1644                         relocate_single_git_dir_into_superproject(prefix, path);
1645
1646                 free(real_sub_git_dir);
1647                 free(real_common_git_dir);
1648         }
1649         strbuf_release(&gitdir);
1650
1651         if (flags & ABSORB_GITDIR_RECURSE_SUBMODULES) {
1652                 struct child_process cp = CHILD_PROCESS_INIT;
1653                 struct strbuf sb = STRBUF_INIT;
1654
1655                 if (flags & ~ABSORB_GITDIR_RECURSE_SUBMODULES)
1656                         die("BUG: we don't know how to pass the flags down?");
1657
1658                 strbuf_addstr(&sb, get_super_prefix_or_empty());
1659                 strbuf_addstr(&sb, path);
1660                 strbuf_addch(&sb, '/');
1661
1662                 cp.dir = path;
1663                 cp.git_cmd = 1;
1664                 cp.no_stdin = 1;
1665                 argv_array_pushl(&cp.args, "--super-prefix", sb.buf,
1666                                            "submodule--helper",
1667                                            "absorb-git-dirs", NULL);
1668                 prepare_submodule_repo_env(&cp.env_array);
1669                 if (run_command(&cp))
1670                         die(_("could not recurse into submodule '%s'"), path);
1671
1672                 strbuf_release(&sb);
1673         }
1674 }
1675
1676 const char *get_superproject_working_tree(void)
1677 {
1678         struct child_process cp = CHILD_PROCESS_INIT;
1679         struct strbuf sb = STRBUF_INIT;
1680         const char *one_up = real_path_if_valid("../");
1681         const char *cwd = xgetcwd();
1682         const char *ret = NULL;
1683         const char *subpath;
1684         int code;
1685         ssize_t len;
1686
1687         if (!is_inside_work_tree())
1688                 /*
1689                  * FIXME:
1690                  * We might have a superproject, but it is harder
1691                  * to determine.
1692                  */
1693                 return NULL;
1694
1695         if (!one_up)
1696                 return NULL;
1697
1698         subpath = relative_path(cwd, one_up, &sb);
1699
1700         prepare_submodule_repo_env(&cp.env_array);
1701         argv_array_pop(&cp.env_array);
1702
1703         argv_array_pushl(&cp.args, "--literal-pathspecs", "-C", "..",
1704                         "ls-files", "-z", "--stage", "--full-name", "--",
1705                         subpath, NULL);
1706         strbuf_reset(&sb);
1707
1708         cp.no_stdin = 1;
1709         cp.no_stderr = 1;
1710         cp.out = -1;
1711         cp.git_cmd = 1;
1712
1713         if (start_command(&cp))
1714                 die(_("could not start ls-files in .."));
1715
1716         len = strbuf_read(&sb, cp.out, PATH_MAX);
1717         close(cp.out);
1718
1719         if (starts_with(sb.buf, "160000")) {
1720                 int super_sub_len;
1721                 int cwd_len = strlen(cwd);
1722                 char *super_sub, *super_wt;
1723
1724                 /*
1725                  * There is a superproject having this repo as a submodule.
1726                  * The format is <mode> SP <hash> SP <stage> TAB <full name> \0,
1727                  * We're only interested in the name after the tab.
1728                  */
1729                 super_sub = strchr(sb.buf, '\t') + 1;
1730                 super_sub_len = sb.buf + sb.len - super_sub - 1;
1731
1732                 if (super_sub_len > cwd_len ||
1733                     strcmp(&cwd[cwd_len - super_sub_len], super_sub))
1734                         die (_("BUG: returned path string doesn't match cwd?"));
1735
1736                 super_wt = xstrdup(cwd);
1737                 super_wt[cwd_len - super_sub_len] = '\0';
1738
1739                 ret = real_path(super_wt);
1740                 free(super_wt);
1741         }
1742         strbuf_release(&sb);
1743
1744         code = finish_command(&cp);
1745
1746         if (code == 128)
1747                 /* '../' is not a git repository */
1748                 return NULL;
1749         if (code == 0 && len == 0)
1750                 /* There is an unrelated git repository at '../' */
1751                 return NULL;
1752         if (code)
1753                 die(_("ls-tree returned unexpected return code %d"), code);
1754
1755         return ret;
1756 }