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  * NEEDSWORK: With the addition of different configuration options to determine
 217  * if a submodule is of interests, the validity of this function's name comes
 218  * into question.  Once the dust has settled and more concrete terminology is
 219  * decided upon, come up with a more proper name for this function.  One
 220  * potential candidate could be 'is_submodule_active()'.
 221  *
 222  * Determine if a submodule has been initialized at a given 'path'
 223  */
 224 int is_submodule_initialized(const char *path)
 225 {
 226         int ret = 0;
 227         char *key = NULL;
 228         char *value = NULL;
 229         const struct string_list *sl;
 230         const struct submodule *module = submodule_from_path(null_sha1, path);
 231
 232         /* early return if there isn't a path->module mapping */
 233         if (!module)
 234                 return 0;
 235
 236         /* submodule.<name>.active is set */
 237         key = xstrfmt("submodule.%s.active", module->name);
 238         if (!git_config_get_bool(key, &ret)) {
 239                 free(key);
 240                 return ret;
 241         }
 242         free(key);
 243
 244         /* submodule.active is set */
 245         sl = git_config_get_value_multi("submodule.active");
 246         if (sl) {
 247                 struct pathspec ps;
 248                 struct argv_array args = ARGV_ARRAY_INIT;
 249                 const struct string_list_item *item;
 250
 251                 for_each_string_list_item(item, sl) {
 252                         argv_array_push(&args, item->string);
 253                 }
 254
 255                 parse_pathspec(&ps, 0, 0, NULL, args.argv);
 256                 ret = match_pathspec(&ps, path, strlen(path), 0, NULL, 1);
 257
 258                 argv_array_clear(&args);
 259                 clear_pathspec(&ps);
 260                 return ret;
 261         }
 262
 263         /* fallback to checking if the URL is set */
 264         key = xstrfmt("submodule.%s.url", module->name);
 265         ret = !git_config_get_string(key, &value);
 266
 267         free(value);
 268         free(key);
 269         return ret;
 270 }
 271
 272 int is_submodule_populated_gently(const char *path, int *return_error_code)
 273 {
 274         int ret = 0;
 275         char *gitdir = xstrfmt("%s/.git", path);
 276
 277         if (resolve_gitdir_gently(gitdir, return_error_code))
 278                 ret = 1;
 279
 280         free(gitdir);
 281         return ret;
 282 }
 283
 284 int parse_submodule_update_strategy(const char *value,
 285                 struct submodule_update_strategy *dst)
 286 {
 287         free((void*)dst->command);
 288         dst->command = NULL;
 289         if (!strcmp(value, "none"))
 290                 dst->type = SM_UPDATE_NONE;
 291         else if (!strcmp(value, "checkout"))
 292                 dst->type = SM_UPDATE_CHECKOUT;
 293         else if (!strcmp(value, "rebase"))
 294                 dst->type = SM_UPDATE_REBASE;
 295         else if (!strcmp(value, "merge"))
 296                 dst->type = SM_UPDATE_MERGE;
 297         else if (skip_prefix(value, "!", &value)) {
 298                 dst->type = SM_UPDATE_COMMAND;
 299                 dst->command = xstrdup(value);
 300         } else
 301                 return -1;
 302         return 0;
 303 }
 304
 305 const char *submodule_strategy_to_string(const struct submodule_update_strategy *s)
 306 {
 307         struct strbuf sb = STRBUF_INIT;
 308         switch (s->type) {
 309         case SM_UPDATE_CHECKOUT:
 310                 return "checkout";
 311         case SM_UPDATE_MERGE:
 312                 return "merge";
 313         case SM_UPDATE_REBASE:
 314                 return "rebase";
 315         case SM_UPDATE_NONE:
 316                 return "none";
 317         case SM_UPDATE_UNSPECIFIED:
 318                 return NULL;
 319         case SM_UPDATE_COMMAND:
 320                 strbuf_addf(&sb, "!%s", s->command);
 321                 return strbuf_detach(&sb, NULL);
 322         }
 323         return NULL;
 324 }
 325
 326 void handle_ignore_submodules_arg(struct diff_options *diffopt,
 327                                   const char *arg)
 328 {
 329         DIFF_OPT_CLR(diffopt, IGNORE_SUBMODULES);
 330         DIFF_OPT_CLR(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 331         DIFF_OPT_CLR(diffopt, IGNORE_DIRTY_SUBMODULES);
 332
 333         if (!strcmp(arg, "all"))
 334                 DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
 335         else if (!strcmp(arg, "untracked"))
 336                 DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 337         else if (!strcmp(arg, "dirty"))
 338                 DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES);
 339         else if (strcmp(arg, "none"))
 340                 die("bad --ignore-submodules argument: %s", arg);
 341 }
 342
 343 static int prepare_submodule_summary(struct rev_info *rev, const char *path,
 344                 struct commit *left, struct commit *right,
 345                 struct commit_list *merge_bases)
 346 {
 347         struct commit_list *list;
 348
 349         init_revisions(rev, NULL);
 350         setup_revisions(0, NULL, rev, NULL);
 351         rev->left_right = 1;
 352         rev->first_parent_only = 1;
 353         left->object.flags |= SYMMETRIC_LEFT;
 354         add_pending_object(rev, &left->object, path);
 355         add_pending_object(rev, &right->object, path);
 356         for (list = merge_bases; list; list = list->next) {
 357                 list->item->object.flags |= UNINTERESTING;
 358                 add_pending_object(rev, &list->item->object,
 359                         oid_to_hex(&list->item->object.oid));
 360         }
 361         return prepare_revision_walk(rev);
 362 }
 363
 364 static void print_submodule_summary(struct rev_info *rev, FILE *f,
 365                 const char *line_prefix,
 366                 const char *del, const char *add, const char *reset)
 367 {
 368         static const char format[] = "  %m %s";
 369         struct strbuf sb = STRBUF_INIT;
 370         struct commit *commit;
 371
 372         while ((commit = get_revision(rev))) {
 373                 struct pretty_print_context ctx = {0};
 374                 ctx.date_mode = rev->date_mode;
 375                 ctx.output_encoding = get_log_output_encoding();
 376                 strbuf_setlen(&sb, 0);
 377                 strbuf_addstr(&sb, line_prefix);
 378                 if (commit->object.flags & SYMMETRIC_LEFT) {
 379                         if (del)
 380                                 strbuf_addstr(&sb, del);
 381                 }
 382                 else if (add)
 383                         strbuf_addstr(&sb, add);
 384                 format_commit_message(commit, format, &sb, &ctx);
 385                 if (reset)
 386                         strbuf_addstr(&sb, reset);
 387                 strbuf_addch(&sb, '\n');
 388                 fprintf(f, "%s", sb.buf);
 389         }
 390         strbuf_release(&sb);
 391 }
 392
 393 static void prepare_submodule_repo_env_no_git_dir(struct argv_array *out)
 394 {
 395         const char * const *var;
 396
 397         for (var = local_repo_env; *var; var++) {
 398                 if (strcmp(*var, CONFIG_DATA_ENVIRONMENT))
 399                         argv_array_push(out, *var);
 400         }
 401 }
 402
 403 void prepare_submodule_repo_env(struct argv_array *out)
 404 {
 405         prepare_submodule_repo_env_no_git_dir(out);
 406         argv_array_pushf(out, "%s=%s", GIT_DIR_ENVIRONMENT,
 407                          DEFAULT_GIT_DIR_ENVIRONMENT);
 408 }
 409
 410 /* Helper function to display the submodule header line prior to the full
 411  * summary output. If it can locate the submodule objects directory it will
 412  * attempt to lookup both the left and right commits and put them into the
 413  * left and right pointers.
 414  */
 415 static void show_submodule_header(FILE *f, const char *path,
 416                 const char *line_prefix,
 417                 struct object_id *one, struct object_id *two,
 418                 unsigned dirty_submodule, const char *meta,
 419                 const char *reset,
 420                 struct commit **left, struct commit **right,
 421                 struct commit_list **merge_bases)
 422 {
 423         const char *message = NULL;
 424         struct strbuf sb = STRBUF_INIT;
 425         int fast_forward = 0, fast_backward = 0;
 426
 427         if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
 428                 fprintf(f, "%sSubmodule %s contains untracked content\n",
 429                         line_prefix, path);
 430         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
 431                 fprintf(f, "%sSubmodule %s contains modified content\n",
 432                         line_prefix, path);
 433
 434         if (is_null_oid(one))
 435                 message = "(new submodule)";
 436         else if (is_null_oid(two))
 437                 message = "(submodule deleted)";
 438
 439         if (add_submodule_odb(path)) {
 440                 if (!message)
 441                         message = "(not initialized)";
 442                 goto output_header;
 443         }
 444
 445         /*
 446          * Attempt to lookup the commit references, and determine if this is
 447          * a fast forward or fast backwards update.
 448          */
 449         *left = lookup_commit_reference(one->hash);
 450         *right = lookup_commit_reference(two->hash);
 451
 452         /*
 453          * Warn about missing commits in the submodule project, but only if
 454          * they aren't null.
 455          */
 456         if ((!is_null_oid(one) && !*left) ||
 457              (!is_null_oid(two) && !*right))
 458                 message = "(commits not present)";
 459
 460         *merge_bases = get_merge_bases(*left, *right);
 461         if (*merge_bases) {
 462                 if ((*merge_bases)->item == *left)
 463                         fast_forward = 1;
 464                 else if ((*merge_bases)->item == *right)
 465                         fast_backward = 1;
 466         }
 467
 468         if (!oidcmp(one, two)) {
 469                 strbuf_release(&sb);
 470                 return;
 471         }
 472
 473 output_header:
 474         strbuf_addf(&sb, "%s%sSubmodule %s ", line_prefix, meta, path);
 475         strbuf_add_unique_abbrev(&sb, one->hash, DEFAULT_ABBREV);
 476         strbuf_addstr(&sb, (fast_backward || fast_forward) ? ".." : "...");
 477         strbuf_add_unique_abbrev(&sb, two->hash, DEFAULT_ABBREV);
 478         if (message)
 479                 strbuf_addf(&sb, " %s%s\n", message, reset);
 480         else
 481                 strbuf_addf(&sb, "%s:%s\n", fast_backward ? " (rewind)" : "", reset);
 482         fwrite(sb.buf, sb.len, 1, f);
 483
 484         strbuf_release(&sb);
 485 }
 486
 487 void show_submodule_summary(FILE *f, const char *path,
 488                 const char *line_prefix,
 489                 struct object_id *one, struct object_id *two,
 490                 unsigned dirty_submodule, const char *meta,
 491                 const char *del, const char *add, const char *reset)
 492 {
 493         struct rev_info rev;
 494         struct commit *left = NULL, *right = NULL;
 495         struct commit_list *merge_bases = NULL;
 496
 497         show_submodule_header(f, path, line_prefix, one, two, dirty_submodule,
 498                               meta, reset, &left, &right, &merge_bases);
 499
 500         /*
 501          * If we don't have both a left and a right pointer, there is no
 502          * reason to try and display a summary. The header line should contain
 503          * all the information the user needs.
 504          */
 505         if (!left || !right)
 506                 goto out;
 507
 508         /* Treat revision walker failure the same as missing commits */
 509         if (prepare_submodule_summary(&rev, path, left, right, merge_bases)) {
 510                 fprintf(f, "%s(revision walker failed)\n", line_prefix);
 511                 goto out;
 512         }
 513
 514         print_submodule_summary(&rev, f, line_prefix, del, add, reset);
 515
 516 out:
 517         if (merge_bases)
 518                 free_commit_list(merge_bases);
 519         clear_commit_marks(left, ~0);
 520         clear_commit_marks(right, ~0);
 521 }
 522
 523 void show_submodule_inline_diff(FILE *f, const char *path,
 524                 const char *line_prefix,
 525                 struct object_id *one, struct object_id *two,
 526                 unsigned dirty_submodule, const char *meta,
 527                 const char *del, const char *add, const char *reset,
 528                 const struct diff_options *o)
 529 {
 530         const struct object_id *old = &empty_tree_oid, *new = &empty_tree_oid;
 531         struct commit *left = NULL, *right = NULL;
 532         struct commit_list *merge_bases = NULL;
 533         struct strbuf submodule_dir = STRBUF_INIT;
 534         struct child_process cp = CHILD_PROCESS_INIT;
 535
 536         show_submodule_header(f, path, line_prefix, one, two, dirty_submodule,
 537                               meta, reset, &left, &right, &merge_bases);
 538
 539         /* We need a valid left and right commit to display a difference */
 540         if (!(left || is_null_oid(one)) ||
 541             !(right || is_null_oid(two)))
 542                 goto done;
 543
 544         if (left)
 545                 old = one;
 546         if (right)
 547                 new = two;
 548
 549         fflush(f);
 550         cp.git_cmd = 1;
 551         cp.dir = path;
 552         cp.out = dup(fileno(f));
 553         cp.no_stdin = 1;
 554
 555         /* TODO: other options may need to be passed here. */
 556         argv_array_push(&cp.args, "diff");
 557         argv_array_pushf(&cp.args, "--line-prefix=%s", line_prefix);
 558         if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
 559                 argv_array_pushf(&cp.args, "--src-prefix=%s%s/",
 560                                  o->b_prefix, path);
 561                 argv_array_pushf(&cp.args, "--dst-prefix=%s%s/",
 562                                  o->a_prefix, path);
 563         } else {
 564                 argv_array_pushf(&cp.args, "--src-prefix=%s%s/",
 565                                  o->a_prefix, path);
 566                 argv_array_pushf(&cp.args, "--dst-prefix=%s%s/",
 567                                  o->b_prefix, path);
 568         }
 569         argv_array_push(&cp.args, oid_to_hex(old));
 570         /*
 571          * If the submodule has modified content, we will diff against the
 572          * work tree, under the assumption that the user has asked for the
 573          * diff format and wishes to actually see all differences even if they
 574          * haven't yet been committed to the submodule yet.
 575          */
 576         if (!(dirty_submodule & DIRTY_SUBMODULE_MODIFIED))
 577                 argv_array_push(&cp.args, oid_to_hex(new));
 578
 579         if (run_command(&cp))
 580                 fprintf(f, "(diff failed)\n");
 581
 582 done:
 583         strbuf_release(&submodule_dir);
 584         if (merge_bases)
 585                 free_commit_list(merge_bases);
 586         if (left)
 587                 clear_commit_marks(left, ~0);
 588         if (right)
 589                 clear_commit_marks(right, ~0);
 590 }
 591
 592 void set_config_fetch_recurse_submodules(int value)
 593 {
 594         config_fetch_recurse_submodules = value;
 595 }
 596
 597 void set_config_update_recurse_submodules(int value)
 598 {
 599         config_update_recurse_submodules = value;
 600 }
 601
 602 int should_update_submodules(void)
 603 {
 604         return config_update_recurse_submodules == RECURSE_SUBMODULES_ON;
 605 }
 606
 607 const struct submodule *submodule_from_ce(const struct cache_entry *ce)
 608 {
 609         if (!S_ISGITLINK(ce->ce_mode))
 610                 return NULL;
 611
 612         if (!should_update_submodules())
 613                 return NULL;
 614
 615         return submodule_from_path(null_sha1, ce->name);
 616 }
 617
 618 static int has_remote(const char *refname, const struct object_id *oid,
 619                       int flags, void *cb_data)
 620 {
 621         return 1;
 622 }
 623
 624 static int append_sha1_to_argv(const unsigned char sha1[20], void *data)
 625 {
 626         struct argv_array *argv = data;
 627         argv_array_push(argv, sha1_to_hex(sha1));
 628         return 0;
 629 }
 630
 631 static int check_has_commit(const unsigned char sha1[20], void *data)
 632 {
 633         int *has_commit = data;
 634
 635         if (!lookup_commit_reference(sha1))
 636                 *has_commit = 0;
 637
 638         return 0;
 639 }
 640
 641 static int submodule_has_commits(const char *path, struct sha1_array *commits)
 642 {
 643         int has_commit = 1;
 644
 645         if (add_submodule_odb(path))
 646                 return 0;
 647
 648         sha1_array_for_each_unique(commits, check_has_commit, &has_commit);
 649         return has_commit;
 650 }
 651
 652 static int submodule_needs_pushing(const char *path, struct sha1_array *commits)
 653 {
 654         if (!submodule_has_commits(path, commits))
 655                 /*
 656                  * NOTE: We do consider it safe to return "no" here. The
 657                  * correct answer would be "We do not know" instead of
 658                  * "No push needed", but it is quite hard to change
 659                  * the submodule pointer without having the submodule
 660                  * around. If a user did however change the submodules
 661                  * without having the submodule around, this indicates
 662                  * an expert who knows what they are doing or a
 663                  * maintainer integrating work from other people. In
 664                  * both cases it should be safe to skip this check.
 665                  */
 666                 return 0;
 667
 668         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 669                 struct child_process cp = CHILD_PROCESS_INIT;
 670                 struct strbuf buf = STRBUF_INIT;
 671                 int needs_pushing = 0;
 672
 673                 argv_array_push(&cp.args, "rev-list");
 674                 sha1_array_for_each_unique(commits, append_sha1_to_argv, &cp.args);
 675                 argv_array_pushl(&cp.args, "--not", "--remotes", "-n", "1" , NULL);
 676
 677                 prepare_submodule_repo_env(&cp.env_array);
 678                 cp.git_cmd = 1;
 679                 cp.no_stdin = 1;
 680                 cp.out = -1;
 681                 cp.dir = path;
 682                 if (start_command(&cp))
 683                         die("Could not run 'git rev-list <commits> --not --remotes -n 1' command in submodule %s",
 684                                         path);
 685                 if (strbuf_read(&buf, cp.out, 41))
 686                         needs_pushing = 1;
 687                 finish_command(&cp);
 688                 close(cp.out);
 689                 strbuf_release(&buf);
 690                 return needs_pushing;
 691         }
 692
 693         return 0;
 694 }
 695
 696 static struct sha1_array *submodule_commits(struct string_list *submodules,
 697                                             const char *path)
 698 {
 699         struct string_list_item *item;
 700
 701         item = string_list_insert(submodules, path);
 702         if (item->util)
 703                 return (struct sha1_array *) item->util;
 704
 705         /* NEEDSWORK: should we have sha1_array_init()? */
 706         item->util = xcalloc(1, sizeof(struct sha1_array));
 707         return (struct sha1_array *) item->util;
 708 }
 709
 710 static void collect_submodules_from_diff(struct diff_queue_struct *q,
 711                                          struct diff_options *options,
 712                                          void *data)
 713 {
 714         int i;
 715         struct string_list *submodules = data;
 716
 717         for (i = 0; i < q->nr; i++) {
 718                 struct diff_filepair *p = q->queue[i];
 719                 struct sha1_array *commits;
 720                 if (!S_ISGITLINK(p->two->mode))
 721                         continue;
 722                 commits = submodule_commits(submodules, p->two->path);
 723                 sha1_array_append(commits, p->two->oid.hash);
 724         }
 725 }
 726
 727 static void find_unpushed_submodule_commits(struct commit *commit,
 728                 struct string_list *needs_pushing)
 729 {
 730         struct rev_info rev;
 731
 732         init_revisions(&rev, NULL);
 733         rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
 734         rev.diffopt.format_callback = collect_submodules_from_diff;
 735         rev.diffopt.format_callback_data = needs_pushing;
 736         diff_tree_combined_merge(commit, 1, &rev);
 737 }
 738
 739 static void free_submodules_sha1s(struct string_list *submodules)
 740 {
 741         struct string_list_item *item;
 742         for_each_string_list_item(item, submodules)
 743                 sha1_array_clear((struct sha1_array *) item->util);
 744         string_list_clear(submodules, 1);
 745 }
 746
 747 int find_unpushed_submodules(struct sha1_array *commits,
 748                 const char *remotes_name, struct string_list *needs_pushing)
 749 {
 750         struct rev_info rev;
 751         struct commit *commit;
 752         struct string_list submodules = STRING_LIST_INIT_DUP;
 753         struct string_list_item *submodule;
 754         struct argv_array argv = ARGV_ARRAY_INIT;
 755
 756         init_revisions(&rev, NULL);
 757
 758         /* argv.argv[0] will be ignored by setup_revisions */
 759         argv_array_push(&argv, "find_unpushed_submodules");
 760         sha1_array_for_each_unique(commits, append_sha1_to_argv, &argv);
 761         argv_array_push(&argv, "--not");
 762         argv_array_pushf(&argv, "--remotes=%s", remotes_name);
 763
 764         setup_revisions(argv.argc, argv.argv, &rev, NULL);
 765         if (prepare_revision_walk(&rev))
 766                 die("revision walk setup failed");
 767
 768         while ((commit = get_revision(&rev)) != NULL)
 769                 find_unpushed_submodule_commits(commit, &submodules);
 770
 771         reset_revision_walk();
 772         argv_array_clear(&argv);
 773
 774         for_each_string_list_item(submodule, &submodules) {
 775                 struct sha1_array *commits = (struct sha1_array *) submodule->util;
 776
 777                 if (submodule_needs_pushing(submodule->string, commits))
 778                         string_list_insert(needs_pushing, submodule->string);
 779         }
 780         free_submodules_sha1s(&submodules);
 781
 782         return needs_pushing->nr;
 783 }
 784
 785 static int push_submodule(const char *path,
 786                           const struct string_list *push_options,
 787                           int dry_run)
 788 {
 789         if (add_submodule_odb(path))
 790                 return 1;
 791
 792         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 793                 struct child_process cp = CHILD_PROCESS_INIT;
 794                 argv_array_push(&cp.args, "push");
 795                 if (dry_run)
 796                         argv_array_push(&cp.args, "--dry-run");
 797
 798                 if (push_options && push_options->nr) {
 799                         const struct string_list_item *item;
 800                         for_each_string_list_item(item, push_options)
 801                                 argv_array_pushf(&cp.args, "--push-option=%s",
 802                                                  item->string);
 803                 }
 804                 prepare_submodule_repo_env(&cp.env_array);
 805                 cp.git_cmd = 1;
 806                 cp.no_stdin = 1;
 807                 cp.dir = path;
 808                 if (run_command(&cp))
 809                         return 0;
 810                 close(cp.out);
 811         }
 812
 813         return 1;
 814 }
 815
 816 int push_unpushed_submodules(struct sha1_array *commits,
 817                              const char *remotes_name,
 818                              const struct string_list *push_options,
 819                              int dry_run)
 820 {
 821         int i, ret = 1;
 822         struct string_list needs_pushing = STRING_LIST_INIT_DUP;
 823
 824         if (!find_unpushed_submodules(commits, remotes_name, &needs_pushing))
 825                 return 1;
 826
 827         for (i = 0; i < needs_pushing.nr; i++) {
 828                 const char *path = needs_pushing.items[i].string;
 829                 fprintf(stderr, "Pushing submodule '%s'\n", path);
 830                 if (!push_submodule(path, push_options, dry_run)) {
 831                         fprintf(stderr, "Unable to push submodule '%s'\n", path);
 832                         ret = 0;
 833                 }
 834         }
 835
 836         string_list_clear(&needs_pushing, 0);
 837
 838         return ret;
 839 }
 840
 841 static int is_submodule_commit_present(const char *path, unsigned char sha1[20])
 842 {
 843         int is_present = 0;
 844         if (!add_submodule_odb(path) && lookup_commit_reference(sha1)) {
 845                 /* Even if the submodule is checked out and the commit is
 846                  * present, make sure it is reachable from a ref. */
 847                 struct child_process cp = CHILD_PROCESS_INIT;
 848                 const char *argv[] = {"rev-list", "-n", "1", NULL, "--not", "--all", NULL};
 849                 struct strbuf buf = STRBUF_INIT;
 850
 851                 argv[3] = sha1_to_hex(sha1);
 852                 cp.argv = argv;
 853                 prepare_submodule_repo_env(&cp.env_array);
 854                 cp.git_cmd = 1;
 855                 cp.no_stdin = 1;
 856                 cp.dir = path;
 857                 if (!capture_command(&cp, &buf, 1024) && !buf.len)
 858                         is_present = 1;
 859
 860                 strbuf_release(&buf);
 861         }
 862         return is_present;
 863 }
 864
 865 static void submodule_collect_changed_cb(struct diff_queue_struct *q,
 866                                          struct diff_options *options,
 867                                          void *data)
 868 {
 869         int i;
 870         for (i = 0; i < q->nr; i++) {
 871                 struct diff_filepair *p = q->queue[i];
 872                 if (!S_ISGITLINK(p->two->mode))
 873                         continue;
 874
 875                 if (S_ISGITLINK(p->one->mode)) {
 876                         /* NEEDSWORK: We should honor the name configured in
 877                          * the .gitmodules file of the commit we are examining
 878                          * here to be able to correctly follow submodules
 879                          * being moved around. */
 880                         struct string_list_item *path;
 881                         path = unsorted_string_list_lookup(&changed_submodule_paths, p->two->path);
 882                         if (!path && !is_submodule_commit_present(p->two->path, p->two->oid.hash))
 883                                 string_list_append(&changed_submodule_paths, xstrdup(p->two->path));
 884                 } else {
 885                         /* Submodule is new or was moved here */
 886                         /* NEEDSWORK: When the .git directories of submodules
 887                          * live inside the superprojects .git directory some
 888                          * day we should fetch new submodules directly into
 889                          * that location too when config or options request
 890                          * that so they can be checked out from there. */
 891                         continue;
 892                 }
 893         }
 894 }
 895
 896 static int add_sha1_to_array(const char *ref, const struct object_id *oid,
 897                              int flags, void *data)
 898 {
 899         sha1_array_append(data, oid->hash);
 900         return 0;
 901 }
 902
 903 void check_for_new_submodule_commits(unsigned char new_sha1[20])
 904 {
 905         if (!initialized_fetch_ref_tips) {
 906                 for_each_ref(add_sha1_to_array, &ref_tips_before_fetch);
 907                 initialized_fetch_ref_tips = 1;
 908         }
 909
 910         sha1_array_append(&ref_tips_after_fetch, new_sha1);
 911 }
 912
 913 static int add_sha1_to_argv(const unsigned char sha1[20], void *data)
 914 {
 915         argv_array_push(data, sha1_to_hex(sha1));
 916         return 0;
 917 }
 918
 919 static void calculate_changed_submodule_paths(void)
 920 {
 921         struct rev_info rev;
 922         struct commit *commit;
 923         struct argv_array argv = ARGV_ARRAY_INIT;
 924
 925         /* No need to check if there are no submodules configured */
 926         if (!submodule_from_path(NULL, NULL))
 927                 return;
 928
 929         init_revisions(&rev, NULL);
 930         argv_array_push(&argv, "--"); /* argv[0] program name */
 931         sha1_array_for_each_unique(&ref_tips_after_fetch,
 932                                    add_sha1_to_argv, &argv);
 933         argv_array_push(&argv, "--not");
 934         sha1_array_for_each_unique(&ref_tips_before_fetch,
 935                                    add_sha1_to_argv, &argv);
 936         setup_revisions(argv.argc, argv.argv, &rev, NULL);
 937         if (prepare_revision_walk(&rev))
 938                 die("revision walk setup failed");
 939
 940         /*
 941          * Collect all submodules (whether checked out or not) for which new
 942          * commits have been recorded upstream in "changed_submodule_paths".
 943          */
 944         while ((commit = get_revision(&rev))) {
 945                 struct commit_list *parent = commit->parents;
 946                 while (parent) {
 947                         struct diff_options diff_opts;
 948                         diff_setup(&diff_opts);
 949                         DIFF_OPT_SET(&diff_opts, RECURSIVE);
 950                         diff_opts.output_format |= DIFF_FORMAT_CALLBACK;
 951                         diff_opts.format_callback = submodule_collect_changed_cb;
 952                         diff_setup_done(&diff_opts);
 953                         diff_tree_sha1(parent->item->object.oid.hash, commit->object.oid.hash, "", &diff_opts);
 954                         diffcore_std(&diff_opts);
 955                         diff_flush(&diff_opts);
 956                         parent = parent->next;
 957                 }
 958         }
 959
 960         argv_array_clear(&argv);
 961         sha1_array_clear(&ref_tips_before_fetch);
 962         sha1_array_clear(&ref_tips_after_fetch);
 963         initialized_fetch_ref_tips = 0;
 964 }
 965
 966 struct submodule_parallel_fetch {
 967         int count;
 968         struct argv_array args;
 969         const char *work_tree;
 970         const char *prefix;
 971         int command_line_option;
 972         int quiet;
 973         int result;
 974 };
 975 #define SPF_INIT {0, ARGV_ARRAY_INIT, NULL, NULL, 0, 0, 0}
 976
 977 static int get_next_submodule(struct child_process *cp,
 978                               struct strbuf *err, void *data, void **task_cb)
 979 {
 980         int ret = 0;
 981         struct submodule_parallel_fetch *spf = data;
 982
 983         for (; spf->count < active_nr; spf->count++) {
 984                 struct strbuf submodule_path = STRBUF_INIT;
 985                 struct strbuf submodule_git_dir = STRBUF_INIT;
 986                 struct strbuf submodule_prefix = STRBUF_INIT;
 987                 const struct cache_entry *ce = active_cache[spf->count];
 988                 const char *git_dir, *default_argv;
 989                 const struct submodule *submodule;
 990
 991                 if (!S_ISGITLINK(ce->ce_mode))
 992                         continue;
 993
 994                 submodule = submodule_from_path(null_sha1, ce->name);
 995                 if (!submodule)
 996                         submodule = submodule_from_name(null_sha1, ce->name);
 997
 998                 default_argv = "yes";
 999                 if (spf->command_line_option == RECURSE_SUBMODULES_DEFAULT) {
1000                         if (submodule &&
1001                             submodule->fetch_recurse !=
1002                                                 RECURSE_SUBMODULES_NONE) {
1003                                 if (submodule->fetch_recurse ==
1004                                                 RECURSE_SUBMODULES_OFF)
1005                                         continue;
1006                                 if (submodule->fetch_recurse ==
1007                                                 RECURSE_SUBMODULES_ON_DEMAND) {
1008                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
1009                                                 continue;
1010                                         default_argv = "on-demand";
1011                                 }
1012                         } else {
1013                                 if ((config_fetch_recurse_submodules == RECURSE_SUBMODULES_OFF) ||
1014                                     gitmodules_is_unmerged)
1015                                         continue;
1016                                 if (config_fetch_recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) {
1017                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
1018                                                 continue;
1019                                         default_argv = "on-demand";
1020                                 }
1021                         }
1022                 } else if (spf->command_line_option == RECURSE_SUBMODULES_ON_DEMAND) {
1023                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
1024                                 continue;
1025                         default_argv = "on-demand";
1026                 }
1027
1028                 strbuf_addf(&submodule_path, "%s/%s", spf->work_tree, ce->name);
1029                 strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
1030                 strbuf_addf(&submodule_prefix, "%s%s/", spf->prefix, ce->name);
1031                 git_dir = read_gitfile(submodule_git_dir.buf);
1032                 if (!git_dir)
1033                         git_dir = submodule_git_dir.buf;
1034                 if (is_directory(git_dir)) {
1035                         child_process_init(cp);
1036                         cp->dir = strbuf_detach(&submodule_path, NULL);
1037                         prepare_submodule_repo_env(&cp->env_array);
1038                         cp->git_cmd = 1;
1039                         if (!spf->quiet)
1040                                 strbuf_addf(err, "Fetching submodule %s%s\n",
1041                                             spf->prefix, ce->name);
1042                         argv_array_init(&cp->args);
1043                         argv_array_pushv(&cp->args, spf->args.argv);
1044                         argv_array_push(&cp->args, default_argv);
1045                         argv_array_push(&cp->args, "--submodule-prefix");
1046                         argv_array_push(&cp->args, submodule_prefix.buf);
1047                         ret = 1;
1048                 }
1049                 strbuf_release(&submodule_path);
1050                 strbuf_release(&submodule_git_dir);
1051                 strbuf_release(&submodule_prefix);
1052                 if (ret) {
1053                         spf->count++;
1054                         return 1;
1055                 }
1056         }
1057         return 0;
1058 }
1059
1060 static int fetch_start_failure(struct strbuf *err,
1061                                void *cb, void *task_cb)
1062 {
1063         struct submodule_parallel_fetch *spf = cb;
1064
1065         spf->result = 1;
1066
1067         return 0;
1068 }
1069
1070 static int fetch_finish(int retvalue, struct strbuf *err,
1071                         void *cb, void *task_cb)
1072 {
1073         struct submodule_parallel_fetch *spf = cb;
1074
1075         if (retvalue)
1076                 spf->result = 1;
1077
1078         return 0;
1079 }
1080
1081 int fetch_populated_submodules(const struct argv_array *options,
1082                                const char *prefix, int command_line_option,
1083                                int quiet, int max_parallel_jobs)
1084 {
1085         int i;
1086         struct submodule_parallel_fetch spf = SPF_INIT;
1087
1088         spf.work_tree = get_git_work_tree();
1089         spf.command_line_option = command_line_option;
1090         spf.quiet = quiet;
1091         spf.prefix = prefix;
1092
1093         if (!spf.work_tree)
1094                 goto out;
1095
1096         if (read_cache() < 0)
1097                 die("index file corrupt");
1098
1099         argv_array_push(&spf.args, "fetch");
1100         for (i = 0; i < options->argc; i++)
1101                 argv_array_push(&spf.args, options->argv[i]);
1102         argv_array_push(&spf.args, "--recurse-submodules-default");
1103         /* default value, "--submodule-prefix" and its value are added later */
1104
1105         if (max_parallel_jobs < 0)
1106                 max_parallel_jobs = parallel_jobs;
1107
1108         calculate_changed_submodule_paths();
1109         run_processes_parallel(max_parallel_jobs,
1110                                get_next_submodule,
1111                                fetch_start_failure,
1112                                fetch_finish,
1113                                &spf);
1114
1115         argv_array_clear(&spf.args);
1116 out:
1117         string_list_clear(&changed_submodule_paths, 1);
1118         return spf.result;
1119 }
1120
1121 unsigned is_submodule_modified(const char *path, int ignore_untracked)
1122 {
1123         ssize_t len;
1124         struct child_process cp = CHILD_PROCESS_INIT;
1125         const char *argv[] = {
1126                 "status",
1127                 "--porcelain",
1128                 NULL,
1129                 NULL,
1130         };
1131         struct strbuf buf = STRBUF_INIT;
1132         unsigned dirty_submodule = 0;
1133         const char *line, *next_line;
1134         const char *git_dir;
1135
1136         strbuf_addf(&buf, "%s/.git", path);
1137         git_dir = read_gitfile(buf.buf);
1138         if (!git_dir)
1139                 git_dir = buf.buf;
1140         if (!is_directory(git_dir)) {
1141                 strbuf_release(&buf);
1142                 /* The submodule is not checked out, so it is not modified */
1143                 return 0;
1144
1145         }
1146         strbuf_reset(&buf);
1147
1148         if (ignore_untracked)
1149                 argv[2] = "-uno";
1150
1151         cp.argv = argv;
1152         prepare_submodule_repo_env(&cp.env_array);
1153         cp.git_cmd = 1;
1154         cp.no_stdin = 1;
1155         cp.out = -1;
1156         cp.dir = path;
1157         if (start_command(&cp))
1158                 die("Could not run 'git status --porcelain' in submodule %s", path);
1159
1160         len = strbuf_read(&buf, cp.out, 1024);
1161         line = buf.buf;
1162         while (len > 2) {
1163                 if ((line[0] == '?') && (line[1] == '?')) {
1164                         dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
1165                         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
1166                                 break;
1167                 } else {
1168                         dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
1169                         if (ignore_untracked ||
1170                             (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED))
1171                                 break;
1172                 }
1173                 next_line = strchr(line, '\n');
1174                 if (!next_line)
1175                         break;
1176                 next_line++;
1177                 len -= (next_line - line);
1178                 line = next_line;
1179         }
1180         close(cp.out);
1181
1182         if (finish_command(&cp))
1183                 die("'git status --porcelain' failed in submodule %s", path);
1184
1185         strbuf_release(&buf);
1186         return dirty_submodule;
1187 }
1188
1189 int submodule_uses_gitfile(const char *path)
1190 {
1191         struct child_process cp = CHILD_PROCESS_INIT;
1192         const char *argv[] = {
1193                 "submodule",
1194                 "foreach",
1195                 "--quiet",
1196                 "--recursive",
1197                 "test -f .git",
1198                 NULL,
1199         };
1200         struct strbuf buf = STRBUF_INIT;
1201         const char *git_dir;
1202
1203         strbuf_addf(&buf, "%s/.git", path);
1204         git_dir = read_gitfile(buf.buf);
1205         if (!git_dir) {
1206                 strbuf_release(&buf);
1207                 return 0;
1208         }
1209         strbuf_release(&buf);
1210
1211         /* Now test that all nested submodules use a gitfile too */
1212         cp.argv = argv;
1213         prepare_submodule_repo_env(&cp.env_array);
1214         cp.git_cmd = 1;
1215         cp.no_stdin = 1;
1216         cp.no_stderr = 1;
1217         cp.no_stdout = 1;
1218         cp.dir = path;
1219         if (run_command(&cp))
1220                 return 0;
1221
1222         return 1;
1223 }
1224
1225 /*
1226  * Check if it is a bad idea to remove a submodule, i.e. if we'd lose data
1227  * when doing so.
1228  *
1229  * Return 1 if we'd lose data, return 0 if the removal is fine,
1230  * and negative values for errors.
1231  */
1232 int bad_to_remove_submodule(const char *path, unsigned flags)
1233 {
1234         ssize_t len;
1235         struct child_process cp = CHILD_PROCESS_INIT;
1236         struct strbuf buf = STRBUF_INIT;
1237         int ret = 0;
1238
1239         if (!file_exists(path) || is_empty_dir(path))
1240                 return 0;
1241
1242         if (!submodule_uses_gitfile(path))
1243                 return 1;
1244
1245         argv_array_pushl(&cp.args, "status", "--porcelain",
1246                                    "--ignore-submodules=none", NULL);
1247
1248         if (flags & SUBMODULE_REMOVAL_IGNORE_UNTRACKED)
1249                 argv_array_push(&cp.args, "-uno");
1250         else
1251                 argv_array_push(&cp.args, "-uall");
1252
1253         if (!(flags & SUBMODULE_REMOVAL_IGNORE_IGNORED_UNTRACKED))
1254                 argv_array_push(&cp.args, "--ignored");
1255
1256         prepare_submodule_repo_env(&cp.env_array);
1257         cp.git_cmd = 1;
1258         cp.no_stdin = 1;
1259         cp.out = -1;
1260         cp.dir = path;
1261         if (start_command(&cp)) {
1262                 if (flags & SUBMODULE_REMOVAL_DIE_ON_ERROR)
1263                         die(_("could not start 'git status in submodule '%s'"),
1264                                 path);
1265                 ret = -1;
1266                 goto out;
1267         }
1268
1269         len = strbuf_read(&buf, cp.out, 1024);
1270         if (len > 2)
1271                 ret = 1;
1272         close(cp.out);
1273
1274         if (finish_command(&cp)) {
1275                 if (flags & SUBMODULE_REMOVAL_DIE_ON_ERROR)
1276                         die(_("could not run 'git status in submodule '%s'"),
1277                                 path);
1278                 ret = -1;
1279         }
1280 out:
1281         strbuf_release(&buf);
1282         return ret;
1283 }
1284
1285 static const char *get_super_prefix_or_empty(void)
1286 {
1287         const char *s = get_super_prefix();
1288         if (!s)
1289                 s = "";
1290         return s;
1291 }
1292
1293 static int submodule_has_dirty_index(const struct submodule *sub)
1294 {
1295         struct child_process cp = CHILD_PROCESS_INIT;
1296
1297         prepare_submodule_repo_env_no_git_dir(&cp.env_array);
1298
1299         cp.git_cmd = 1;
1300         argv_array_pushl(&cp.args, "diff-index", "--quiet",
1301                                    "--cached", "HEAD", NULL);
1302         cp.no_stdin = 1;
1303         cp.no_stdout = 1;
1304         cp.dir = sub->path;
1305         if (start_command(&cp))
1306                 die("could not recurse into submodule '%s'", sub->path);
1307
1308         return finish_command(&cp);
1309 }
1310
1311 static void submodule_reset_index(const char *path)
1312 {
1313         struct child_process cp = CHILD_PROCESS_INIT;
1314         prepare_submodule_repo_env_no_git_dir(&cp.env_array);
1315
1316         cp.git_cmd = 1;
1317         cp.no_stdin = 1;
1318         cp.dir = path;
1319
1320         argv_array_pushf(&cp.args, "--super-prefix=%s%s/",
1321                                    get_super_prefix_or_empty(), path);
1322         argv_array_pushl(&cp.args, "read-tree", "-u", "--reset", NULL);
1323
1324         argv_array_push(&cp.args, EMPTY_TREE_SHA1_HEX);
1325
1326         if (run_command(&cp))
1327                 die("could not reset submodule index");
1328 }
1329
1330 /**
1331  * Moves a submodule at a given path from a given head to another new head.
1332  * For edge cases (a submodule coming into existence or removing a submodule)
1333  * pass NULL for old or new respectively.
1334  */
1335 int submodule_move_head(const char *path,
1336                          const char *old,
1337                          const char *new,
1338                          unsigned flags)
1339 {
1340         int ret = 0;
1341         struct child_process cp = CHILD_PROCESS_INIT;
1342         const struct submodule *sub;
1343
1344         sub = submodule_from_path(null_sha1, path);
1345
1346         if (!sub)
1347                 die("BUG: could not get submodule information for '%s'", path);
1348
1349         if (old && !(flags & SUBMODULE_MOVE_HEAD_FORCE)) {
1350                 /* Check if the submodule has a dirty index. */
1351                 if (submodule_has_dirty_index(sub))
1352                         return error(_("submodule '%s' has dirty index"), path);
1353         }
1354
1355         if (!(flags & SUBMODULE_MOVE_HEAD_DRY_RUN)) {
1356                 if (old) {
1357                         if (!submodule_uses_gitfile(path))
1358                                 absorb_git_dir_into_superproject("", path,
1359                                         ABSORB_GITDIR_RECURSE_SUBMODULES);
1360                 } else {
1361                         struct strbuf sb = STRBUF_INIT;
1362                         strbuf_addf(&sb, "%s/modules/%s",
1363                                     get_git_common_dir(), sub->name);
1364                         connect_work_tree_and_git_dir(path, sb.buf);
1365                         strbuf_release(&sb);
1366
1367                         /* make sure the index is clean as well */
1368                         submodule_reset_index(path);
1369                 }
1370         }
1371
1372         prepare_submodule_repo_env_no_git_dir(&cp.env_array);
1373
1374         cp.git_cmd = 1;
1375         cp.no_stdin = 1;
1376         cp.dir = path;
1377
1378         argv_array_pushf(&cp.args, "--super-prefix=%s%s/",
1379                         get_super_prefix_or_empty(), path);
1380         argv_array_pushl(&cp.args, "read-tree", NULL);
1381
1382         if (flags & SUBMODULE_MOVE_HEAD_DRY_RUN)
1383                 argv_array_push(&cp.args, "-n");
1384         else
1385                 argv_array_push(&cp.args, "-u");
1386
1387         if (flags & SUBMODULE_MOVE_HEAD_FORCE)
1388                 argv_array_push(&cp.args, "--reset");
1389         else
1390                 argv_array_push(&cp.args, "-m");
1391
1392         argv_array_push(&cp.args, old ? old : EMPTY_TREE_SHA1_HEX);
1393         argv_array_push(&cp.args, new ? new : EMPTY_TREE_SHA1_HEX);
1394
1395         if (run_command(&cp)) {
1396                 ret = -1;
1397                 goto out;
1398         }
1399
1400         if (!(flags & SUBMODULE_MOVE_HEAD_DRY_RUN)) {
1401                 if (new) {
1402                         struct child_process cp1 = CHILD_PROCESS_INIT;
1403                         /* also set the HEAD accordingly */
1404                         cp1.git_cmd = 1;
1405                         cp1.no_stdin = 1;
1406                         cp1.dir = path;
1407
1408                         argv_array_pushl(&cp1.args, "update-ref", "HEAD",
1409                                          new ? new : EMPTY_TREE_SHA1_HEX, NULL);
1410
1411                         if (run_command(&cp1)) {
1412                                 ret = -1;
1413                                 goto out;
1414                         }
1415                 } else {
1416                         struct strbuf sb = STRBUF_INIT;
1417
1418                         strbuf_addf(&sb, "%s/.git", path);
1419                         unlink_or_warn(sb.buf);
1420                         strbuf_release(&sb);
1421
1422                         if (is_empty_dir(path))
1423                                 rmdir_or_warn(path);
1424                 }
1425         }
1426 out:
1427         return ret;
1428 }
1429
1430 static int find_first_merges(struct object_array *result, const char *path,
1431                 struct commit *a, struct commit *b)
1432 {
1433         int i, j;
1434         struct object_array merges = OBJECT_ARRAY_INIT;
1435         struct commit *commit;
1436         int contains_another;
1437
1438         char merged_revision[42];
1439         const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
1440                                    "--all", merged_revision, NULL };
1441         struct rev_info revs;
1442         struct setup_revision_opt rev_opts;
1443
1444         memset(result, 0, sizeof(struct object_array));
1445         memset(&rev_opts, 0, sizeof(rev_opts));
1446
1447         /* get all revisions that merge commit a */
1448         snprintf(merged_revision, sizeof(merged_revision), "^%s",
1449                         oid_to_hex(&a->object.oid));
1450         init_revisions(&revs, NULL);
1451         rev_opts.submodule = path;
1452         setup_revisions(ARRAY_SIZE(rev_args)-1, rev_args, &revs, &rev_opts);
1453
1454         /* save all revisions from the above list that contain b */
1455         if (prepare_revision_walk(&revs))
1456                 die("revision walk setup failed");
1457         while ((commit = get_revision(&revs)) != NULL) {
1458                 struct object *o = &(commit->object);
1459                 if (in_merge_bases(b, commit))
1460                         add_object_array(o, NULL, &merges);
1461         }
1462         reset_revision_walk();
1463
1464         /* Now we've got all merges that contain a and b. Prune all
1465          * merges that contain another found merge and save them in
1466          * result.
1467          */
1468         for (i = 0; i < merges.nr; i++) {
1469                 struct commit *m1 = (struct commit *) merges.objects[i].item;
1470
1471                 contains_another = 0;
1472                 for (j = 0; j < merges.nr; j++) {
1473                         struct commit *m2 = (struct commit *) merges.objects[j].item;
1474                         if (i != j && in_merge_bases(m2, m1)) {
1475                                 contains_another = 1;
1476                                 break;
1477                         }
1478                 }
1479
1480                 if (!contains_another)
1481                         add_object_array(merges.objects[i].item, NULL, result);
1482         }
1483
1484         free(merges.objects);
1485         return result->nr;
1486 }
1487
1488 static void print_commit(struct commit *commit)
1489 {
1490         struct strbuf sb = STRBUF_INIT;
1491         struct pretty_print_context ctx = {0};
1492         ctx.date_mode.type = DATE_NORMAL;
1493         format_commit_message(commit, " %h: %m %s", &sb, &ctx);
1494         fprintf(stderr, "%s\n", sb.buf);
1495         strbuf_release(&sb);
1496 }
1497
1498 #define MERGE_WARNING(path, msg) \
1499         warning("Failed to merge submodule %s (%s)", path, msg);
1500
1501 int merge_submodule(unsigned char result[20], const char *path,
1502                     const unsigned char base[20], const unsigned char a[20],
1503                     const unsigned char b[20], int search)
1504 {
1505         struct commit *commit_base, *commit_a, *commit_b;
1506         int parent_count;
1507         struct object_array merges;
1508
1509         int i;
1510
1511         /* store a in result in case we fail */
1512         hashcpy(result, a);
1513
1514         /* we can not handle deletion conflicts */
1515         if (is_null_sha1(base))
1516                 return 0;
1517         if (is_null_sha1(a))
1518                 return 0;
1519         if (is_null_sha1(b))
1520                 return 0;
1521
1522         if (add_submodule_odb(path)) {
1523                 MERGE_WARNING(path, "not checked out");
1524                 return 0;
1525         }
1526
1527         if (!(commit_base = lookup_commit_reference(base)) ||
1528             !(commit_a = lookup_commit_reference(a)) ||
1529             !(commit_b = lookup_commit_reference(b))) {
1530                 MERGE_WARNING(path, "commits not present");
1531                 return 0;
1532         }
1533
1534         /* check whether both changes are forward */
1535         if (!in_merge_bases(commit_base, commit_a) ||
1536             !in_merge_bases(commit_base, commit_b)) {
1537                 MERGE_WARNING(path, "commits don't follow merge-base");
1538                 return 0;
1539         }
1540
1541         /* Case #1: a is contained in b or vice versa */
1542         if (in_merge_bases(commit_a, commit_b)) {
1543                 hashcpy(result, b);
1544                 return 1;
1545         }
1546         if (in_merge_bases(commit_b, commit_a)) {
1547                 hashcpy(result, a);
1548                 return 1;
1549         }
1550
1551         /*
1552          * Case #2: There are one or more merges that contain a and b in
1553          * the submodule. If there is only one, then present it as a
1554          * suggestion to the user, but leave it marked unmerged so the
1555          * user needs to confirm the resolution.
1556          */
1557
1558         /* Skip the search if makes no sense to the calling context.  */
1559         if (!search)
1560                 return 0;
1561
1562         /* find commit which merges them */
1563         parent_count = find_first_merges(&merges, path, commit_a, commit_b);
1564         switch (parent_count) {
1565         case 0:
1566                 MERGE_WARNING(path, "merge following commits not found");
1567                 break;
1568
1569         case 1:
1570                 MERGE_WARNING(path, "not fast-forward");
1571                 fprintf(stderr, "Found a possible merge resolution "
1572                                 "for the submodule:\n");
1573                 print_commit((struct commit *) merges.objects[0].item);
1574                 fprintf(stderr,
1575                         "If this is correct simply add it to the index "
1576                         "for example\n"
1577                         "by using:\n\n"
1578                         "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1579                         "which will accept this suggestion.\n",
1580                         oid_to_hex(&merges.objects[0].item->oid), path);
1581                 break;
1582
1583         default:
1584                 MERGE_WARNING(path, "multiple merges found");
1585                 for (i = 0; i < merges.nr; i++)
1586                         print_commit((struct commit *) merges.objects[i].item);
1587         }
1588
1589         free(merges.objects);
1590         return 0;
1591 }
1592
1593 int parallel_submodules(void)
1594 {
1595         return parallel_jobs;
1596 }
1597
1598 /*
1599  * Embeds a single submodules git directory into the superprojects git dir,
1600  * non recursively.
1601  */
1602 static void relocate_single_git_dir_into_superproject(const char *prefix,
1603                                                       const char *path)
1604 {
1605         char *old_git_dir = NULL, *real_old_git_dir = NULL, *real_new_git_dir = NULL;
1606         const char *new_git_dir;
1607         const struct submodule *sub;
1608
1609         if (submodule_uses_worktrees(path))
1610                 die(_("relocate_gitdir for submodule '%s' with "
1611                       "more than one worktree not supported"), path);
1612
1613         old_git_dir = xstrfmt("%s/.git", path);
1614         if (read_gitfile(old_git_dir))
1615                 /* If it is an actual gitfile, it doesn't need migration. */
1616                 return;
1617
1618         real_old_git_dir = real_pathdup(old_git_dir, 1);
1619
1620         sub = submodule_from_path(null_sha1, path);
1621         if (!sub)
1622                 die(_("could not lookup name for submodule '%s'"), path);
1623
1624         new_git_dir = git_path("modules/%s", sub->name);
1625         if (safe_create_leading_directories_const(new_git_dir) < 0)
1626                 die(_("could not create directory '%s'"), new_git_dir);
1627         real_new_git_dir = real_pathdup(new_git_dir, 1);
1628
1629         fprintf(stderr, _("Migrating git directory of '%s%s' from\n'%s' to\n'%s'\n"),
1630                 get_super_prefix_or_empty(), path,
1631                 real_old_git_dir, real_new_git_dir);
1632
1633         relocate_gitdir(path, real_old_git_dir, real_new_git_dir);
1634
1635         free(old_git_dir);
1636         free(real_old_git_dir);
1637         free(real_new_git_dir);
1638 }
1639
1640 /*
1641  * Migrate the git directory of the submodule given by path from
1642  * having its git directory within the working tree to the git dir nested
1643  * in its superprojects git dir under modules/.
1644  */
1645 void absorb_git_dir_into_superproject(const char *prefix,
1646                                       const char *path,
1647                                       unsigned flags)
1648 {
1649         int err_code;
1650         const char *sub_git_dir;
1651         struct strbuf gitdir = STRBUF_INIT;
1652         strbuf_addf(&gitdir, "%s/.git", path);
1653         sub_git_dir = resolve_gitdir_gently(gitdir.buf, &err_code);
1654
1655         /* Not populated? */
1656         if (!sub_git_dir) {
1657                 const struct submodule *sub;
1658
1659                 if (err_code == READ_GITFILE_ERR_STAT_FAILED) {
1660                         /* unpopulated as expected */
1661                         strbuf_release(&gitdir);
1662                         return;
1663                 }
1664
1665                 if (err_code != READ_GITFILE_ERR_NOT_A_REPO)
1666                         /* We don't know what broke here. */
1667                         read_gitfile_error_die(err_code, path, NULL);
1668
1669                 /*
1670                 * Maybe populated, but no git directory was found?
1671                 * This can happen if the superproject is a submodule
1672                 * itself and was just absorbed. The absorption of the
1673                 * superproject did not rewrite the git file links yet,
1674                 * fix it now.
1675                 */
1676                 sub = submodule_from_path(null_sha1, path);
1677                 if (!sub)
1678                         die(_("could not lookup name for submodule '%s'"), path);
1679                 connect_work_tree_and_git_dir(path,
1680                         git_path("modules/%s", sub->name));
1681         } else {
1682                 /* Is it already absorbed into the superprojects git dir? */
1683                 char *real_sub_git_dir = real_pathdup(sub_git_dir, 1);
1684                 char *real_common_git_dir = real_pathdup(get_git_common_dir(), 1);
1685
1686                 if (!starts_with(real_sub_git_dir, real_common_git_dir))
1687                         relocate_single_git_dir_into_superproject(prefix, path);
1688
1689                 free(real_sub_git_dir);
1690                 free(real_common_git_dir);
1691         }
1692         strbuf_release(&gitdir);
1693
1694         if (flags & ABSORB_GITDIR_RECURSE_SUBMODULES) {
1695                 struct child_process cp = CHILD_PROCESS_INIT;
1696                 struct strbuf sb = STRBUF_INIT;
1697
1698                 if (flags & ~ABSORB_GITDIR_RECURSE_SUBMODULES)
1699                         die("BUG: we don't know how to pass the flags down?");
1700
1701                 strbuf_addstr(&sb, get_super_prefix_or_empty());
1702                 strbuf_addstr(&sb, path);
1703                 strbuf_addch(&sb, '/');
1704
1705                 cp.dir = path;
1706                 cp.git_cmd = 1;
1707                 cp.no_stdin = 1;
1708                 argv_array_pushl(&cp.args, "--super-prefix", sb.buf,
1709                                            "submodule--helper",
1710                                            "absorb-git-dirs", NULL);
1711                 prepare_submodule_repo_env(&cp.env_array);
1712                 if (run_command(&cp))
1713                         die(_("could not recurse into submodule '%s'"), path);
1714
1715                 strbuf_release(&sb);
1716         }
1717 }
1718
1719 const char *get_superproject_working_tree(void)
1720 {
1721         struct child_process cp = CHILD_PROCESS_INIT;
1722         struct strbuf sb = STRBUF_INIT;
1723         const char *one_up = real_path_if_valid("../");
1724         const char *cwd = xgetcwd();
1725         const char *ret = NULL;
1726         const char *subpath;
1727         int code;
1728         ssize_t len;
1729
1730         if (!is_inside_work_tree())
1731                 /*
1732                  * FIXME:
1733                  * We might have a superproject, but it is harder
1734                  * to determine.
1735                  */
1736                 return NULL;
1737
1738         if (!one_up)
1739                 return NULL;
1740
1741         subpath = relative_path(cwd, one_up, &sb);
1742
1743         prepare_submodule_repo_env(&cp.env_array);
1744         argv_array_pop(&cp.env_array);
1745
1746         argv_array_pushl(&cp.args, "--literal-pathspecs", "-C", "..",
1747                         "ls-files", "-z", "--stage", "--full-name", "--",
1748                         subpath, NULL);
1749         strbuf_reset(&sb);
1750
1751         cp.no_stdin = 1;
1752         cp.no_stderr = 1;
1753         cp.out = -1;
1754         cp.git_cmd = 1;
1755
1756         if (start_command(&cp))
1757                 die(_("could not start ls-files in .."));
1758
1759         len = strbuf_read(&sb, cp.out, PATH_MAX);
1760         close(cp.out);
1761
1762         if (starts_with(sb.buf, "160000")) {
1763                 int super_sub_len;
1764                 int cwd_len = strlen(cwd);
1765                 char *super_sub, *super_wt;
1766
1767                 /*
1768                  * There is a superproject having this repo as a submodule.
1769                  * The format is <mode> SP <hash> SP <stage> TAB <full name> \0,
1770                  * We're only interested in the name after the tab.
1771                  */
1772                 super_sub = strchr(sb.buf, '\t') + 1;
1773                 super_sub_len = sb.buf + sb.len - super_sub - 1;
1774
1775                 if (super_sub_len > cwd_len ||
1776                     strcmp(&cwd[cwd_len - super_sub_len], super_sub))
1777                         die (_("BUG: returned path string doesn't match cwd?"));
1778
1779                 super_wt = xstrdup(cwd);
1780                 super_wt[cwd_len - super_sub_len] = '\0';
1781
1782                 ret = real_path(super_wt);
1783                 free(super_wt);
1784         }
1785         strbuf_release(&sb);
1786
1787         code = finish_command(&cp);
1788
1789         if (code == 128)
1790                 /* '../' is not a git repository */
1791                 return NULL;
1792         if (code == 0 && len == 0)
1793                 /* There is an unrelated git repository at '../' */
1794                 return NULL;
1795         if (code)
1796                 die(_("ls-tree returned unexpected return code %d"), code);
1797
1798         return ret;
1799 }