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
  17 static int config_fetch_recurse_submodules = RECURSE_SUBMODULES_ON_DEMAND;
  18 static struct string_list changed_submodule_paths;
  19 static int initialized_fetch_ref_tips;
  20 static struct sha1_array ref_tips_before_fetch;
  21 static struct sha1_array ref_tips_after_fetch;
  22
  23 /*
  24  * The following flag is set if the .gitmodules file is unmerged. We then
  25  * disable recursion for all submodules where .git/config doesn't have a
  26  * matching config entry because we can't guess what might be configured in
  27  * .gitmodules unless the user resolves the conflict. When a command line
  28  * option is given (which always overrides configuration) this flag will be
  29  * ignored.
  30  */
  31 static int gitmodules_is_unmerged;
  32
  33 /*
  34  * This flag is set if the .gitmodules file had unstaged modifications on
  35  * startup. This must be checked before allowing modifications to the
  36  * .gitmodules file with the intention to stage them later, because when
  37  * continuing we would stage the modifications the user didn't stage herself
  38  * too. That might change in a future version when we learn to stage the
  39  * changes we do ourselves without staging any previous modifications.
  40  */
  41 static int gitmodules_is_modified;
  42
  43 int is_staging_gitmodules_ok(void)
  44 {
  45         return !gitmodules_is_modified;
  46 }
  47
  48 /*
  49  * Try to update the "path" entry in the "submodule.<name>" section of the
  50  * .gitmodules file. Return 0 only if a .gitmodules file was found, a section
  51  * with the correct path=<oldpath> setting was found and we could update it.
  52  */
  53 int update_path_in_gitmodules(const char *oldpath, const char *newpath)
  54 {
  55         struct strbuf entry = STRBUF_INIT;
  56         const struct submodule *submodule;
  57
  58         if (!file_exists(".gitmodules")) /* Do nothing without .gitmodules */
  59                 return -1;
  60
  61         if (gitmodules_is_unmerged)
  62                 die(_("Cannot change unmerged .gitmodules, resolve merge conflicts first"));
  63
  64         submodule = submodule_from_path(null_sha1, oldpath);
  65         if (!submodule || !submodule->name) {
  66                 warning(_("Could not find section in .gitmodules where path=%s"), oldpath);
  67                 return -1;
  68         }
  69         strbuf_addstr(&entry, "submodule.");
  70         strbuf_addstr(&entry, submodule->name);
  71         strbuf_addstr(&entry, ".path");
  72         if (git_config_set_in_file(".gitmodules", entry.buf, newpath) < 0) {
  73                 /* Maybe the user already did that, don't error out here */
  74                 warning(_("Could not update .gitmodules entry %s"), entry.buf);
  75                 strbuf_release(&entry);
  76                 return -1;
  77         }
  78         strbuf_release(&entry);
  79         return 0;
  80 }
  81
  82 /*
  83  * Try to remove the "submodule.<name>" section from .gitmodules where the given
  84  * path is configured. Return 0 only if a .gitmodules file was found, a section
  85  * with the correct path=<path> setting was found and we could remove it.
  86  */
  87 int remove_path_from_gitmodules(const char *path)
  88 {
  89         struct strbuf sect = STRBUF_INIT;
  90         const struct submodule *submodule;
  91
  92         if (!file_exists(".gitmodules")) /* Do nothing without .gitmodules */
  93                 return -1;
  94
  95         if (gitmodules_is_unmerged)
  96                 die(_("Cannot change unmerged .gitmodules, resolve merge conflicts first"));
  97
  98         submodule = submodule_from_path(null_sha1, path);
  99         if (!submodule || !submodule->name) {
 100                 warning(_("Could not find section in .gitmodules where path=%s"), path);
 101                 return -1;
 102         }
 103         strbuf_addstr(&sect, "submodule.");
 104         strbuf_addstr(&sect, submodule->name);
 105         if (git_config_rename_section_in_file(".gitmodules", sect.buf, NULL) < 0) {
 106                 /* Maybe the user already did that, don't error out here */
 107                 warning(_("Could not remove .gitmodules entry for %s"), path);
 108                 strbuf_release(&sect);
 109                 return -1;
 110         }
 111         strbuf_release(&sect);
 112         return 0;
 113 }
 114
 115 void stage_updated_gitmodules(void)
 116 {
 117         if (add_file_to_cache(".gitmodules", 0))
 118                 die(_("staging updated .gitmodules failed"));
 119 }
 120
 121 static int add_submodule_odb(const char *path)
 122 {
 123         struct strbuf objects_directory = STRBUF_INIT;
 124         struct alternate_object_database *alt_odb;
 125         int ret = 0;
 126         int alloc;
 127
 128         strbuf_git_path_submodule(&objects_directory, path, "objects/");
 129         if (!is_directory(objects_directory.buf)) {
 130                 ret = -1;
 131                 goto done;
 132         }
 133         /* avoid adding it twice */
 134         prepare_alt_odb();
 135         for (alt_odb = alt_odb_list; alt_odb; alt_odb = alt_odb->next)
 136                 if (alt_odb->name - alt_odb->base == objects_directory.len &&
 137                                 !strncmp(alt_odb->base, objects_directory.buf,
 138                                         objects_directory.len))
 139                         goto done;
 140
 141         alloc = objects_directory.len + 42; /* for "12/345..." sha1 */
 142         alt_odb = xmalloc(sizeof(*alt_odb) + alloc);
 143         alt_odb->next = alt_odb_list;
 144         xsnprintf(alt_odb->base, alloc, "%s", objects_directory.buf);
 145         alt_odb->name = alt_odb->base + objects_directory.len;
 146         alt_odb->name[2] = '/';
 147         alt_odb->name[40] = '\0';
 148         alt_odb->name[41] = '\0';
 149         alt_odb_list = alt_odb;
 150
 151         /* add possible alternates from the submodule */
 152         read_info_alternates(objects_directory.buf, 0);
 153 done:
 154         strbuf_release(&objects_directory);
 155         return ret;
 156 }
 157
 158 void set_diffopt_flags_from_submodule_config(struct diff_options *diffopt,
 159                                              const char *path)
 160 {
 161         const struct submodule *submodule = submodule_from_path(null_sha1, path);
 162         if (submodule) {
 163                 if (submodule->ignore)
 164                         handle_ignore_submodules_arg(diffopt, submodule->ignore);
 165                 else if (gitmodules_is_unmerged)
 166                         DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
 167         }
 168 }
 169
 170 int submodule_config(const char *var, const char *value, void *cb)
 171 {
 172         if (starts_with(var, "submodule."))
 173                 return parse_submodule_config_option(var, value);
 174         else if (!strcmp(var, "fetch.recursesubmodules")) {
 175                 config_fetch_recurse_submodules = parse_fetch_recurse_submodules_arg(var, value);
 176                 return 0;
 177         }
 178         return 0;
 179 }
 180
 181 void gitmodules_config(void)
 182 {
 183         const char *work_tree = get_git_work_tree();
 184         if (work_tree) {
 185                 struct strbuf gitmodules_path = STRBUF_INIT;
 186                 int pos;
 187                 strbuf_addstr(&gitmodules_path, work_tree);
 188                 strbuf_addstr(&gitmodules_path, "/.gitmodules");
 189                 if (read_cache() < 0)
 190                         die("index file corrupt");
 191                 pos = cache_name_pos(".gitmodules", 11);
 192                 if (pos < 0) { /* .gitmodules not found or isn't merged */
 193                         pos = -1 - pos;
 194                         if (active_nr > pos) {  /* there is a .gitmodules */
 195                                 const struct cache_entry *ce = active_cache[pos];
 196                                 if (ce_namelen(ce) == 11 &&
 197                                     !memcmp(ce->name, ".gitmodules", 11))
 198                                         gitmodules_is_unmerged = 1;
 199                         }
 200                 } else if (pos < active_nr) {
 201                         struct stat st;
 202                         if (lstat(".gitmodules", &st) == 0 &&
 203                             ce_match_stat(active_cache[pos], &st, 0) & DATA_CHANGED)
 204                                 gitmodules_is_modified = 1;
 205                 }
 206
 207                 if (!gitmodules_is_unmerged)
 208                         git_config_from_file(submodule_config, gitmodules_path.buf, NULL);
 209                 strbuf_release(&gitmodules_path);
 210         }
 211 }
 212
 213 int parse_submodule_update_strategy(const char *value,
 214                 struct submodule_update_strategy *dst)
 215 {
 216         free((void*)dst->command);
 217         dst->command = NULL;
 218         if (!strcmp(value, "none"))
 219                 dst->type = SM_UPDATE_NONE;
 220         else if (!strcmp(value, "checkout"))
 221                 dst->type = SM_UPDATE_CHECKOUT;
 222         else if (!strcmp(value, "rebase"))
 223                 dst->type = SM_UPDATE_REBASE;
 224         else if (!strcmp(value, "merge"))
 225                 dst->type = SM_UPDATE_MERGE;
 226         else if (skip_prefix(value, "!", &value)) {
 227                 dst->type = SM_UPDATE_COMMAND;
 228                 dst->command = xstrdup(value);
 229         } else
 230                 return -1;
 231         return 0;
 232 }
 233
 234 void handle_ignore_submodules_arg(struct diff_options *diffopt,
 235                                   const char *arg)
 236 {
 237         DIFF_OPT_CLR(diffopt, IGNORE_SUBMODULES);
 238         DIFF_OPT_CLR(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 239         DIFF_OPT_CLR(diffopt, IGNORE_DIRTY_SUBMODULES);
 240
 241         if (!strcmp(arg, "all"))
 242                 DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
 243         else if (!strcmp(arg, "untracked"))
 244                 DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 245         else if (!strcmp(arg, "dirty"))
 246                 DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES);
 247         else if (strcmp(arg, "none"))
 248                 die("bad --ignore-submodules argument: %s", arg);
 249 }
 250
 251 static int prepare_submodule_summary(struct rev_info *rev, const char *path,
 252                 struct commit *left, struct commit *right,
 253                 int *fast_forward, int *fast_backward)
 254 {
 255         struct commit_list *merge_bases, *list;
 256
 257         init_revisions(rev, NULL);
 258         setup_revisions(0, NULL, rev, NULL);
 259         rev->left_right = 1;
 260         rev->first_parent_only = 1;
 261         left->object.flags |= SYMMETRIC_LEFT;
 262         add_pending_object(rev, &left->object, path);
 263         add_pending_object(rev, &right->object, path);
 264         merge_bases = get_merge_bases(left, right);
 265         if (merge_bases) {
 266                 if (merge_bases->item == left)
 267                         *fast_forward = 1;
 268                 else if (merge_bases->item == right)
 269                         *fast_backward = 1;
 270         }
 271         for (list = merge_bases; list; list = list->next) {
 272                 list->item->object.flags |= UNINTERESTING;
 273                 add_pending_object(rev, &list->item->object,
 274                         oid_to_hex(&list->item->object.oid));
 275         }
 276         return prepare_revision_walk(rev);
 277 }
 278
 279 static void print_submodule_summary(struct rev_info *rev, FILE *f,
 280                 const char *line_prefix,
 281                 const char *del, const char *add, const char *reset)
 282 {
 283         static const char format[] = "  %m %s";
 284         struct strbuf sb = STRBUF_INIT;
 285         struct commit *commit;
 286
 287         while ((commit = get_revision(rev))) {
 288                 struct pretty_print_context ctx = {0};
 289                 ctx.date_mode = rev->date_mode;
 290                 ctx.output_encoding = get_log_output_encoding();
 291                 strbuf_setlen(&sb, 0);
 292                 strbuf_addstr(&sb, line_prefix);
 293                 if (commit->object.flags & SYMMETRIC_LEFT) {
 294                         if (del)
 295                                 strbuf_addstr(&sb, del);
 296                 }
 297                 else if (add)
 298                         strbuf_addstr(&sb, add);
 299                 format_commit_message(commit, format, &sb, &ctx);
 300                 if (reset)
 301                         strbuf_addstr(&sb, reset);
 302                 strbuf_addch(&sb, '\n');
 303                 fprintf(f, "%s", sb.buf);
 304         }
 305         strbuf_release(&sb);
 306 }
 307
 308 void show_submodule_summary(FILE *f, const char *path,
 309                 const char *line_prefix,
 310                 unsigned char one[20], unsigned char two[20],
 311                 unsigned dirty_submodule, const char *meta,
 312                 const char *del, const char *add, const char *reset)
 313 {
 314         struct rev_info rev;
 315         struct commit *left = NULL, *right = NULL;
 316         const char *message = NULL;
 317         struct strbuf sb = STRBUF_INIT;
 318         int fast_forward = 0, fast_backward = 0;
 319
 320         if (is_null_sha1(two))
 321                 message = "(submodule deleted)";
 322         else if (add_submodule_odb(path))
 323                 message = "(not checked out)";
 324         else if (is_null_sha1(one))
 325                 message = "(new submodule)";
 326         else if (!(left = lookup_commit_reference(one)) ||
 327                  !(right = lookup_commit_reference(two)))
 328                 message = "(commits not present)";
 329         else if (prepare_submodule_summary(&rev, path, left, right,
 330                                            &fast_forward, &fast_backward))
 331                 message = "(revision walker failed)";
 332
 333         if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
 334                 fprintf(f, "%sSubmodule %s contains untracked content\n",
 335                         line_prefix, path);
 336         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
 337                 fprintf(f, "%sSubmodule %s contains modified content\n",
 338                         line_prefix, path);
 339
 340         if (!hashcmp(one, two)) {
 341                 strbuf_release(&sb);
 342                 return;
 343         }
 344
 345         strbuf_addf(&sb, "%s%sSubmodule %s %s..", line_prefix, meta, path,
 346                         find_unique_abbrev(one, DEFAULT_ABBREV));
 347         if (!fast_backward && !fast_forward)
 348                 strbuf_addch(&sb, '.');
 349         strbuf_addf(&sb, "%s", find_unique_abbrev(two, DEFAULT_ABBREV));
 350         if (message)
 351                 strbuf_addf(&sb, " %s%s\n", message, reset);
 352         else
 353                 strbuf_addf(&sb, "%s:%s\n", fast_backward ? " (rewind)" : "", reset);
 354         fwrite(sb.buf, sb.len, 1, f);
 355
 356         if (!message) /* only NULL if we succeeded in setting up the walk */
 357                 print_submodule_summary(&rev, f, line_prefix, del, add, reset);
 358         if (left)
 359                 clear_commit_marks(left, ~0);
 360         if (right)
 361                 clear_commit_marks(right, ~0);
 362
 363         strbuf_release(&sb);
 364 }
 365
 366 void set_config_fetch_recurse_submodules(int value)
 367 {
 368         config_fetch_recurse_submodules = value;
 369 }
 370
 371 static int has_remote(const char *refname, const struct object_id *oid,
 372                       int flags, void *cb_data)
 373 {
 374         return 1;
 375 }
 376
 377 static int submodule_needs_pushing(const char *path, const unsigned char sha1[20])
 378 {
 379         if (add_submodule_odb(path) || !lookup_commit_reference(sha1))
 380                 return 0;
 381
 382         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 383                 struct child_process cp = CHILD_PROCESS_INIT;
 384                 const char *argv[] = {"rev-list", NULL, "--not", "--remotes", "-n", "1" , NULL};
 385                 struct strbuf buf = STRBUF_INIT;
 386                 int needs_pushing = 0;
 387
 388                 argv[1] = sha1_to_hex(sha1);
 389                 cp.argv = argv;
 390                 cp.env = local_repo_env;
 391                 cp.git_cmd = 1;
 392                 cp.no_stdin = 1;
 393                 cp.out = -1;
 394                 cp.dir = path;
 395                 if (start_command(&cp))
 396                         die("Could not run 'git rev-list %s --not --remotes -n 1' command in submodule %s",
 397                                 sha1_to_hex(sha1), path);
 398                 if (strbuf_read(&buf, cp.out, 41))
 399                         needs_pushing = 1;
 400                 finish_command(&cp);
 401                 close(cp.out);
 402                 strbuf_release(&buf);
 403                 return needs_pushing;
 404         }
 405
 406         return 0;
 407 }
 408
 409 static void collect_submodules_from_diff(struct diff_queue_struct *q,
 410                                          struct diff_options *options,
 411                                          void *data)
 412 {
 413         int i;
 414         struct string_list *needs_pushing = data;
 415
 416         for (i = 0; i < q->nr; i++) {
 417                 struct diff_filepair *p = q->queue[i];
 418                 if (!S_ISGITLINK(p->two->mode))
 419                         continue;
 420                 if (submodule_needs_pushing(p->two->path, p->two->sha1))
 421                         string_list_insert(needs_pushing, p->two->path);
 422         }
 423 }
 424
 425 static void find_unpushed_submodule_commits(struct commit *commit,
 426                 struct string_list *needs_pushing)
 427 {
 428         struct rev_info rev;
 429
 430         init_revisions(&rev, NULL);
 431         rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
 432         rev.diffopt.format_callback = collect_submodules_from_diff;
 433         rev.diffopt.format_callback_data = needs_pushing;
 434         diff_tree_combined_merge(commit, 1, &rev);
 435 }
 436
 437 int find_unpushed_submodules(unsigned char new_sha1[20],
 438                 const char *remotes_name, struct string_list *needs_pushing)
 439 {
 440         struct rev_info rev;
 441         struct commit *commit;
 442         const char *argv[] = {NULL, NULL, "--not", "NULL", NULL};
 443         int argc = ARRAY_SIZE(argv) - 1;
 444         char *sha1_copy;
 445
 446         struct strbuf remotes_arg = STRBUF_INIT;
 447
 448         strbuf_addf(&remotes_arg, "--remotes=%s", remotes_name);
 449         init_revisions(&rev, NULL);
 450         sha1_copy = xstrdup(sha1_to_hex(new_sha1));
 451         argv[1] = sha1_copy;
 452         argv[3] = remotes_arg.buf;
 453         setup_revisions(argc, argv, &rev, NULL);
 454         if (prepare_revision_walk(&rev))
 455                 die("revision walk setup failed");
 456
 457         while ((commit = get_revision(&rev)) != NULL)
 458                 find_unpushed_submodule_commits(commit, needs_pushing);
 459
 460         reset_revision_walk();
 461         free(sha1_copy);
 462         strbuf_release(&remotes_arg);
 463
 464         return needs_pushing->nr;
 465 }
 466
 467 static int push_submodule(const char *path)
 468 {
 469         if (add_submodule_odb(path))
 470                 return 1;
 471
 472         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 473                 struct child_process cp = CHILD_PROCESS_INIT;
 474                 const char *argv[] = {"push", NULL};
 475
 476                 cp.argv = argv;
 477                 cp.env = local_repo_env;
 478                 cp.git_cmd = 1;
 479                 cp.no_stdin = 1;
 480                 cp.dir = path;
 481                 if (run_command(&cp))
 482                         return 0;
 483                 close(cp.out);
 484         }
 485
 486         return 1;
 487 }
 488
 489 int push_unpushed_submodules(unsigned char new_sha1[20], const char *remotes_name)
 490 {
 491         int i, ret = 1;
 492         struct string_list needs_pushing = STRING_LIST_INIT_DUP;
 493
 494         if (!find_unpushed_submodules(new_sha1, remotes_name, &needs_pushing))
 495                 return 1;
 496
 497         for (i = 0; i < needs_pushing.nr; i++) {
 498                 const char *path = needs_pushing.items[i].string;
 499                 fprintf(stderr, "Pushing submodule '%s'\n", path);
 500                 if (!push_submodule(path)) {
 501                         fprintf(stderr, "Unable to push submodule '%s'\n", path);
 502                         ret = 0;
 503                 }
 504         }
 505
 506         string_list_clear(&needs_pushing, 0);
 507
 508         return ret;
 509 }
 510
 511 static int is_submodule_commit_present(const char *path, unsigned char sha1[20])
 512 {
 513         int is_present = 0;
 514         if (!add_submodule_odb(path) && lookup_commit_reference(sha1)) {
 515                 /* Even if the submodule is checked out and the commit is
 516                  * present, make sure it is reachable from a ref. */
 517                 struct child_process cp = CHILD_PROCESS_INIT;
 518                 const char *argv[] = {"rev-list", "-n", "1", NULL, "--not", "--all", NULL};
 519                 struct strbuf buf = STRBUF_INIT;
 520
 521                 argv[3] = sha1_to_hex(sha1);
 522                 cp.argv = argv;
 523                 cp.env = local_repo_env;
 524                 cp.git_cmd = 1;
 525                 cp.no_stdin = 1;
 526                 cp.dir = path;
 527                 if (!capture_command(&cp, &buf, 1024) && !buf.len)
 528                         is_present = 1;
 529
 530                 strbuf_release(&buf);
 531         }
 532         return is_present;
 533 }
 534
 535 static void submodule_collect_changed_cb(struct diff_queue_struct *q,
 536                                          struct diff_options *options,
 537                                          void *data)
 538 {
 539         int i;
 540         for (i = 0; i < q->nr; i++) {
 541                 struct diff_filepair *p = q->queue[i];
 542                 if (!S_ISGITLINK(p->two->mode))
 543                         continue;
 544
 545                 if (S_ISGITLINK(p->one->mode)) {
 546                         /* NEEDSWORK: We should honor the name configured in
 547                          * the .gitmodules file of the commit we are examining
 548                          * here to be able to correctly follow submodules
 549                          * being moved around. */
 550                         struct string_list_item *path;
 551                         path = unsorted_string_list_lookup(&changed_submodule_paths, p->two->path);
 552                         if (!path && !is_submodule_commit_present(p->two->path, p->two->sha1))
 553                                 string_list_append(&changed_submodule_paths, xstrdup(p->two->path));
 554                 } else {
 555                         /* Submodule is new or was moved here */
 556                         /* NEEDSWORK: When the .git directories of submodules
 557                          * live inside the superprojects .git directory some
 558                          * day we should fetch new submodules directly into
 559                          * that location too when config or options request
 560                          * that so they can be checked out from there. */
 561                         continue;
 562                 }
 563         }
 564 }
 565
 566 static int add_sha1_to_array(const char *ref, const struct object_id *oid,
 567                              int flags, void *data)
 568 {
 569         sha1_array_append(data, oid->hash);
 570         return 0;
 571 }
 572
 573 void check_for_new_submodule_commits(unsigned char new_sha1[20])
 574 {
 575         if (!initialized_fetch_ref_tips) {
 576                 for_each_ref(add_sha1_to_array, &ref_tips_before_fetch);
 577                 initialized_fetch_ref_tips = 1;
 578         }
 579
 580         sha1_array_append(&ref_tips_after_fetch, new_sha1);
 581 }
 582
 583 static void add_sha1_to_argv(const unsigned char sha1[20], void *data)
 584 {
 585         argv_array_push(data, sha1_to_hex(sha1));
 586 }
 587
 588 static void calculate_changed_submodule_paths(void)
 589 {
 590         struct rev_info rev;
 591         struct commit *commit;
 592         struct argv_array argv = ARGV_ARRAY_INIT;
 593
 594         /* No need to check if there are no submodules configured */
 595         if (!submodule_from_path(NULL, NULL))
 596                 return;
 597
 598         init_revisions(&rev, NULL);
 599         argv_array_push(&argv, "--"); /* argv[0] program name */
 600         sha1_array_for_each_unique(&ref_tips_after_fetch,
 601                                    add_sha1_to_argv, &argv);
 602         argv_array_push(&argv, "--not");
 603         sha1_array_for_each_unique(&ref_tips_before_fetch,
 604                                    add_sha1_to_argv, &argv);
 605         setup_revisions(argv.argc, argv.argv, &rev, NULL);
 606         if (prepare_revision_walk(&rev))
 607                 die("revision walk setup failed");
 608
 609         /*
 610          * Collect all submodules (whether checked out or not) for which new
 611          * commits have been recorded upstream in "changed_submodule_paths".
 612          */
 613         while ((commit = get_revision(&rev))) {
 614                 struct commit_list *parent = commit->parents;
 615                 while (parent) {
 616                         struct diff_options diff_opts;
 617                         diff_setup(&diff_opts);
 618                         DIFF_OPT_SET(&diff_opts, RECURSIVE);
 619                         diff_opts.output_format |= DIFF_FORMAT_CALLBACK;
 620                         diff_opts.format_callback = submodule_collect_changed_cb;
 621                         diff_setup_done(&diff_opts);
 622                         diff_tree_sha1(parent->item->object.oid.hash, commit->object.oid.hash, "", &diff_opts);
 623                         diffcore_std(&diff_opts);
 624                         diff_flush(&diff_opts);
 625                         parent = parent->next;
 626                 }
 627         }
 628
 629         argv_array_clear(&argv);
 630         sha1_array_clear(&ref_tips_before_fetch);
 631         sha1_array_clear(&ref_tips_after_fetch);
 632         initialized_fetch_ref_tips = 0;
 633 }
 634
 635 struct submodule_parallel_fetch {
 636         int count;
 637         struct argv_array args;
 638         const char *work_tree;
 639         const char *prefix;
 640         int command_line_option;
 641         int quiet;
 642         int result;
 643 };
 644 #define SPF_INIT {0, ARGV_ARRAY_INIT, NULL, NULL, 0, 0, 0}
 645
 646 static int get_next_submodule(struct child_process *cp,
 647                               struct strbuf *err, void *data, void **task_cb)
 648 {
 649         int ret = 0;
 650         struct submodule_parallel_fetch *spf = data;
 651
 652         for (; spf->count < active_nr; spf->count++) {
 653                 struct strbuf submodule_path = STRBUF_INIT;
 654                 struct strbuf submodule_git_dir = STRBUF_INIT;
 655                 struct strbuf submodule_prefix = STRBUF_INIT;
 656                 const struct cache_entry *ce = active_cache[spf->count];
 657                 const char *git_dir, *default_argv;
 658                 const struct submodule *submodule;
 659
 660                 if (!S_ISGITLINK(ce->ce_mode))
 661                         continue;
 662
 663                 submodule = submodule_from_path(null_sha1, ce->name);
 664                 if (!submodule)
 665                         submodule = submodule_from_name(null_sha1, ce->name);
 666
 667                 default_argv = "yes";
 668                 if (spf->command_line_option == RECURSE_SUBMODULES_DEFAULT) {
 669                         if (submodule &&
 670                             submodule->fetch_recurse !=
 671                                                 RECURSE_SUBMODULES_NONE) {
 672                                 if (submodule->fetch_recurse ==
 673                                                 RECURSE_SUBMODULES_OFF)
 674                                         continue;
 675                                 if (submodule->fetch_recurse ==
 676                                                 RECURSE_SUBMODULES_ON_DEMAND) {
 677                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 678                                                 continue;
 679                                         default_argv = "on-demand";
 680                                 }
 681                         } else {
 682                                 if ((config_fetch_recurse_submodules == RECURSE_SUBMODULES_OFF) ||
 683                                     gitmodules_is_unmerged)
 684                                         continue;
 685                                 if (config_fetch_recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) {
 686                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 687                                                 continue;
 688                                         default_argv = "on-demand";
 689                                 }
 690                         }
 691                 } else if (spf->command_line_option == RECURSE_SUBMODULES_ON_DEMAND) {
 692                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 693                                 continue;
 694                         default_argv = "on-demand";
 695                 }
 696
 697                 strbuf_addf(&submodule_path, "%s/%s", spf->work_tree, ce->name);
 698                 strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
 699                 strbuf_addf(&submodule_prefix, "%s%s/", spf->prefix, ce->name);
 700                 git_dir = read_gitfile(submodule_git_dir.buf);
 701                 if (!git_dir)
 702                         git_dir = submodule_git_dir.buf;
 703                 if (is_directory(git_dir)) {
 704                         child_process_init(cp);
 705                         cp->dir = strbuf_detach(&submodule_path, NULL);
 706                         cp->env = local_repo_env;
 707                         cp->git_cmd = 1;
 708                         if (!spf->quiet)
 709                                 strbuf_addf(err, "Fetching submodule %s%s\n",
 710                                             spf->prefix, ce->name);
 711                         argv_array_init(&cp->args);
 712                         argv_array_pushv(&cp->args, spf->args.argv);
 713                         argv_array_push(&cp->args, default_argv);
 714                         argv_array_push(&cp->args, "--submodule-prefix");
 715                         argv_array_push(&cp->args, submodule_prefix.buf);
 716                         ret = 1;
 717                 }
 718                 strbuf_release(&submodule_path);
 719                 strbuf_release(&submodule_git_dir);
 720                 strbuf_release(&submodule_prefix);
 721                 if (ret) {
 722                         spf->count++;
 723                         return 1;
 724                 }
 725         }
 726         return 0;
 727 }
 728
 729 static int fetch_start_failure(struct strbuf *err,
 730                                void *cb, void *task_cb)
 731 {
 732         struct submodule_parallel_fetch *spf = cb;
 733
 734         spf->result = 1;
 735
 736         return 0;
 737 }
 738
 739 static int fetch_finish(int retvalue, struct strbuf *err,
 740                         void *cb, void *task_cb)
 741 {
 742         struct submodule_parallel_fetch *spf = cb;
 743
 744         if (retvalue)
 745                 spf->result = 1;
 746
 747         return 0;
 748 }
 749
 750 int fetch_populated_submodules(const struct argv_array *options,
 751                                const char *prefix, int command_line_option,
 752                                int quiet, int max_parallel_jobs)
 753 {
 754         int i;
 755         struct submodule_parallel_fetch spf = SPF_INIT;
 756
 757         spf.work_tree = get_git_work_tree();
 758         spf.command_line_option = command_line_option;
 759         spf.quiet = quiet;
 760         spf.prefix = prefix;
 761
 762         if (!spf.work_tree)
 763                 goto out;
 764
 765         if (read_cache() < 0)
 766                 die("index file corrupt");
 767
 768         argv_array_push(&spf.args, "fetch");
 769         for (i = 0; i < options->argc; i++)
 770                 argv_array_push(&spf.args, options->argv[i]);
 771         argv_array_push(&spf.args, "--recurse-submodules-default");
 772         /* default value, "--submodule-prefix" and its value are added later */
 773
 774         calculate_changed_submodule_paths();
 775         run_processes_parallel(max_parallel_jobs,
 776                                get_next_submodule,
 777                                fetch_start_failure,
 778                                fetch_finish,
 779                                &spf);
 780
 781         argv_array_clear(&spf.args);
 782 out:
 783         string_list_clear(&changed_submodule_paths, 1);
 784         return spf.result;
 785 }
 786
 787 unsigned is_submodule_modified(const char *path, int ignore_untracked)
 788 {
 789         ssize_t len;
 790         struct child_process cp = CHILD_PROCESS_INIT;
 791         const char *argv[] = {
 792                 "status",
 793                 "--porcelain",
 794                 NULL,
 795                 NULL,
 796         };
 797         struct strbuf buf = STRBUF_INIT;
 798         unsigned dirty_submodule = 0;
 799         const char *line, *next_line;
 800         const char *git_dir;
 801
 802         strbuf_addf(&buf, "%s/.git", path);
 803         git_dir = read_gitfile(buf.buf);
 804         if (!git_dir)
 805                 git_dir = buf.buf;
 806         if (!is_directory(git_dir)) {
 807                 strbuf_release(&buf);
 808                 /* The submodule is not checked out, so it is not modified */
 809                 return 0;
 810
 811         }
 812         strbuf_reset(&buf);
 813
 814         if (ignore_untracked)
 815                 argv[2] = "-uno";
 816
 817         cp.argv = argv;
 818         cp.env = local_repo_env;
 819         cp.git_cmd = 1;
 820         cp.no_stdin = 1;
 821         cp.out = -1;
 822         cp.dir = path;
 823         if (start_command(&cp))
 824                 die("Could not run 'git status --porcelain' in submodule %s", path);
 825
 826         len = strbuf_read(&buf, cp.out, 1024);
 827         line = buf.buf;
 828         while (len > 2) {
 829                 if ((line[0] == '?') && (line[1] == '?')) {
 830                         dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
 831                         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
 832                                 break;
 833                 } else {
 834                         dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
 835                         if (ignore_untracked ||
 836                             (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED))
 837                                 break;
 838                 }
 839                 next_line = strchr(line, '\n');
 840                 if (!next_line)
 841                         break;
 842                 next_line++;
 843                 len -= (next_line - line);
 844                 line = next_line;
 845         }
 846         close(cp.out);
 847
 848         if (finish_command(&cp))
 849                 die("'git status --porcelain' failed in submodule %s", path);
 850
 851         strbuf_release(&buf);
 852         return dirty_submodule;
 853 }
 854
 855 int submodule_uses_gitfile(const char *path)
 856 {
 857         struct child_process cp = CHILD_PROCESS_INIT;
 858         const char *argv[] = {
 859                 "submodule",
 860                 "foreach",
 861                 "--quiet",
 862                 "--recursive",
 863                 "test -f .git",
 864                 NULL,
 865         };
 866         struct strbuf buf = STRBUF_INIT;
 867         const char *git_dir;
 868
 869         strbuf_addf(&buf, "%s/.git", path);
 870         git_dir = read_gitfile(buf.buf);
 871         if (!git_dir) {
 872                 strbuf_release(&buf);
 873                 return 0;
 874         }
 875         strbuf_release(&buf);
 876
 877         /* Now test that all nested submodules use a gitfile too */
 878         cp.argv = argv;
 879         cp.env = local_repo_env;
 880         cp.git_cmd = 1;
 881         cp.no_stdin = 1;
 882         cp.no_stderr = 1;
 883         cp.no_stdout = 1;
 884         cp.dir = path;
 885         if (run_command(&cp))
 886                 return 0;
 887
 888         return 1;
 889 }
 890
 891 int ok_to_remove_submodule(const char *path)
 892 {
 893         ssize_t len;
 894         struct child_process cp = CHILD_PROCESS_INIT;
 895         const char *argv[] = {
 896                 "status",
 897                 "--porcelain",
 898                 "-u",
 899                 "--ignore-submodules=none",
 900                 NULL,
 901         };
 902         struct strbuf buf = STRBUF_INIT;
 903         int ok_to_remove = 1;
 904
 905         if (!file_exists(path) || is_empty_dir(path))
 906                 return 1;
 907
 908         if (!submodule_uses_gitfile(path))
 909                 return 0;
 910
 911         cp.argv = argv;
 912         cp.env = local_repo_env;
 913         cp.git_cmd = 1;
 914         cp.no_stdin = 1;
 915         cp.out = -1;
 916         cp.dir = path;
 917         if (start_command(&cp))
 918                 die("Could not run 'git status --porcelain -uall --ignore-submodules=none' in submodule %s", path);
 919
 920         len = strbuf_read(&buf, cp.out, 1024);
 921         if (len > 2)
 922                 ok_to_remove = 0;
 923         close(cp.out);
 924
 925         if (finish_command(&cp))
 926                 die("'git status --porcelain -uall --ignore-submodules=none' failed in submodule %s", path);
 927
 928         strbuf_release(&buf);
 929         return ok_to_remove;
 930 }
 931
 932 static int find_first_merges(struct object_array *result, const char *path,
 933                 struct commit *a, struct commit *b)
 934 {
 935         int i, j;
 936         struct object_array merges = OBJECT_ARRAY_INIT;
 937         struct commit *commit;
 938         int contains_another;
 939
 940         char merged_revision[42];
 941         const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
 942                                    "--all", merged_revision, NULL };
 943         struct rev_info revs;
 944         struct setup_revision_opt rev_opts;
 945
 946         memset(result, 0, sizeof(struct object_array));
 947         memset(&rev_opts, 0, sizeof(rev_opts));
 948
 949         /* get all revisions that merge commit a */
 950         snprintf(merged_revision, sizeof(merged_revision), "^%s",
 951                         oid_to_hex(&a->object.oid));
 952         init_revisions(&revs, NULL);
 953         rev_opts.submodule = path;
 954         setup_revisions(ARRAY_SIZE(rev_args)-1, rev_args, &revs, &rev_opts);
 955
 956         /* save all revisions from the above list that contain b */
 957         if (prepare_revision_walk(&revs))
 958                 die("revision walk setup failed");
 959         while ((commit = get_revision(&revs)) != NULL) {
 960                 struct object *o = &(commit->object);
 961                 if (in_merge_bases(b, commit))
 962                         add_object_array(o, NULL, &merges);
 963         }
 964         reset_revision_walk();
 965
 966         /* Now we've got all merges that contain a and b. Prune all
 967          * merges that contain another found merge and save them in
 968          * result.
 969          */
 970         for (i = 0; i < merges.nr; i++) {
 971                 struct commit *m1 = (struct commit *) merges.objects[i].item;
 972
 973                 contains_another = 0;
 974                 for (j = 0; j < merges.nr; j++) {
 975                         struct commit *m2 = (struct commit *) merges.objects[j].item;
 976                         if (i != j && in_merge_bases(m2, m1)) {
 977                                 contains_another = 1;
 978                                 break;
 979                         }
 980                 }
 981
 982                 if (!contains_another)
 983                         add_object_array(merges.objects[i].item, NULL, result);
 984         }
 985
 986         free(merges.objects);
 987         return result->nr;
 988 }
 989
 990 static void print_commit(struct commit *commit)
 991 {
 992         struct strbuf sb = STRBUF_INIT;
 993         struct pretty_print_context ctx = {0};
 994         ctx.date_mode.type = DATE_NORMAL;
 995         format_commit_message(commit, " %h: %m %s", &sb, &ctx);
 996         fprintf(stderr, "%s\n", sb.buf);
 997         strbuf_release(&sb);
 998 }
 999
1000 #define MERGE_WARNING(path, msg) \
1001         warning("Failed to merge submodule %s (%s)", path, msg);
1002
1003 int merge_submodule(unsigned char result[20], const char *path,
1004                     const unsigned char base[20], const unsigned char a[20],
1005                     const unsigned char b[20], int search)
1006 {
1007         struct commit *commit_base, *commit_a, *commit_b;
1008         int parent_count;
1009         struct object_array merges;
1010
1011         int i;
1012
1013         /* store a in result in case we fail */
1014         hashcpy(result, a);
1015
1016         /* we can not handle deletion conflicts */
1017         if (is_null_sha1(base))
1018                 return 0;
1019         if (is_null_sha1(a))
1020                 return 0;
1021         if (is_null_sha1(b))
1022                 return 0;
1023
1024         if (add_submodule_odb(path)) {
1025                 MERGE_WARNING(path, "not checked out");
1026                 return 0;
1027         }
1028
1029         if (!(commit_base = lookup_commit_reference(base)) ||
1030             !(commit_a = lookup_commit_reference(a)) ||
1031             !(commit_b = lookup_commit_reference(b))) {
1032                 MERGE_WARNING(path, "commits not present");
1033                 return 0;
1034         }
1035
1036         /* check whether both changes are forward */
1037         if (!in_merge_bases(commit_base, commit_a) ||
1038             !in_merge_bases(commit_base, commit_b)) {
1039                 MERGE_WARNING(path, "commits don't follow merge-base");
1040                 return 0;
1041         }
1042
1043         /* Case #1: a is contained in b or vice versa */
1044         if (in_merge_bases(commit_a, commit_b)) {
1045                 hashcpy(result, b);
1046                 return 1;
1047         }
1048         if (in_merge_bases(commit_b, commit_a)) {
1049                 hashcpy(result, a);
1050                 return 1;
1051         }
1052
1053         /*
1054          * Case #2: There are one or more merges that contain a and b in
1055          * the submodule. If there is only one, then present it as a
1056          * suggestion to the user, but leave it marked unmerged so the
1057          * user needs to confirm the resolution.
1058          */
1059
1060         /* Skip the search if makes no sense to the calling context.  */
1061         if (!search)
1062                 return 0;
1063
1064         /* find commit which merges them */
1065         parent_count = find_first_merges(&merges, path, commit_a, commit_b);
1066         switch (parent_count) {
1067         case 0:
1068                 MERGE_WARNING(path, "merge following commits not found");
1069                 break;
1070
1071         case 1:
1072                 MERGE_WARNING(path, "not fast-forward");
1073                 fprintf(stderr, "Found a possible merge resolution "
1074                                 "for the submodule:\n");
1075                 print_commit((struct commit *) merges.objects[0].item);
1076                 fprintf(stderr,
1077                         "If this is correct simply add it to the index "
1078                         "for example\n"
1079                         "by using:\n\n"
1080                         "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1081                         "which will accept this suggestion.\n",
1082                         oid_to_hex(&merges.objects[0].item->oid), path);
1083                 break;
1084
1085         default:
1086                 MERGE_WARNING(path, "multiple merges found");
1087                 for (i = 0; i < merges.nr; i++)
1088                         print_commit((struct commit *) merges.objects[i].item);
1089         }
1090
1091         free(merges.objects);
1092         return 0;
1093 }
1094
1095 /* Update gitfile and core.worktree setting to connect work tree and git dir */
1096 void connect_work_tree_and_git_dir(const char *work_tree, const char *git_dir)
1097 {
1098         struct strbuf file_name = STRBUF_INIT;
1099         struct strbuf rel_path = STRBUF_INIT;
1100         const char *real_work_tree = xstrdup(real_path(work_tree));
1101
1102         /* Update gitfile */
1103         strbuf_addf(&file_name, "%s/.git", work_tree);
1104         write_file(file_name.buf, "gitdir: %s",
1105                    relative_path(git_dir, real_work_tree, &rel_path));
1106
1107         /* Update core.worktree setting */
1108         strbuf_reset(&file_name);
1109         strbuf_addf(&file_name, "%s/config", git_dir);
1110         if (git_config_set_in_file(file_name.buf, "core.worktree",
1111                                    relative_path(real_work_tree, git_dir,
1112                                                  &rel_path)))
1113                 die(_("Could not set core.worktree in %s"),
1114                     file_name.buf);
1115
1116         strbuf_release(&file_name);
1117         strbuf_release(&rel_path);
1118         free((void *)real_work_tree);
1119 }