submodule.c

   1 #include "cache.h"
   2 #include "submodule.h"
   3 #include "dir.h"
   4 #include "diff.h"
   5 #include "commit.h"
   6 #include "revision.h"
   7 #include "run-command.h"
   8 #include "diffcore.h"
   9 #include "refs.h"
  10 #include "string-list.h"
  11 #include "sha1-array.h"
  12 #include "argv-array.h"
  13
  14 static struct string_list config_name_for_path;
  15 static struct string_list config_fetch_recurse_submodules_for_name;
  16 static struct string_list config_ignore_for_name;
  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 static int add_submodule_odb(const char *path)
  34 {
  35         struct strbuf objects_directory = STRBUF_INIT;
  36         struct alternate_object_database *alt_odb;
  37         int ret = 0;
  38         const char *git_dir;
  39
  40         strbuf_addf(&objects_directory, "%s/.git", path);
  41         git_dir = read_gitfile(objects_directory.buf);
  42         if (git_dir) {
  43                 strbuf_reset(&objects_directory);
  44                 strbuf_addstr(&objects_directory, git_dir);
  45         }
  46         strbuf_addstr(&objects_directory, "/objects/");
  47         if (!is_directory(objects_directory.buf)) {
  48                 ret = -1;
  49                 goto done;
  50         }
  51         /* avoid adding it twice */
  52         for (alt_odb = alt_odb_list; alt_odb; alt_odb = alt_odb->next)
  53                 if (alt_odb->name - alt_odb->base == objects_directory.len &&
  54                                 !strncmp(alt_odb->base, objects_directory.buf,
  55                                         objects_directory.len))
  56                         goto done;
  57
  58         alt_odb = xmalloc(objects_directory.len + 42 + sizeof(*alt_odb));
  59         alt_odb->next = alt_odb_list;
  60         strcpy(alt_odb->base, objects_directory.buf);
  61         alt_odb->name = alt_odb->base + objects_directory.len;
  62         alt_odb->name[2] = '/';
  63         alt_odb->name[40] = '\0';
  64         alt_odb->name[41] = '\0';
  65         alt_odb_list = alt_odb;
  66
  67         /* add possible alternates from the submodule */
  68         read_info_alternates(objects_directory.buf, 0);
  69         prepare_alt_odb();
  70 done:
  71         strbuf_release(&objects_directory);
  72         return ret;
  73 }
  74
  75 void set_diffopt_flags_from_submodule_config(struct diff_options *diffopt,
  76                                              const char *path)
  77 {
  78         struct string_list_item *path_option, *ignore_option;
  79         path_option = unsorted_string_list_lookup(&config_name_for_path, path);
  80         if (path_option) {
  81                 ignore_option = unsorted_string_list_lookup(&config_ignore_for_name, path_option->util);
  82                 if (ignore_option)
  83                         handle_ignore_submodules_arg(diffopt, ignore_option->util);
  84                 else if (gitmodules_is_unmerged)
  85                         DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
  86         }
  87 }
  88
  89 int submodule_config(const char *var, const char *value, void *cb)
  90 {
  91         if (!prefixcmp(var, "submodule."))
  92                 return parse_submodule_config_option(var, value);
  93         else if (!strcmp(var, "fetch.recursesubmodules")) {
  94                 config_fetch_recurse_submodules = parse_fetch_recurse_submodules_arg(var, value);
  95                 return 0;
  96         }
  97         return 0;
  98 }
  99
 100 void gitmodules_config(void)
 101 {
 102         const char *work_tree = get_git_work_tree();
 103         if (work_tree) {
 104                 struct strbuf gitmodules_path = STRBUF_INIT;
 105                 int pos;
 106                 strbuf_addstr(&gitmodules_path, work_tree);
 107                 strbuf_addstr(&gitmodules_path, "/.gitmodules");
 108                 if (read_cache() < 0)
 109                         die("index file corrupt");
 110                 pos = cache_name_pos(".gitmodules", 11);
 111                 if (pos < 0) { /* .gitmodules not found or isn't merged */
 112                         pos = -1 - pos;
 113                         if (active_nr > pos) {  /* there is a .gitmodules */
 114                                 const struct cache_entry *ce = active_cache[pos];
 115                                 if (ce_namelen(ce) == 11 &&
 116                                     !memcmp(ce->name, ".gitmodules", 11))
 117                                         gitmodules_is_unmerged = 1;
 118                         }
 119                 }
 120
 121                 if (!gitmodules_is_unmerged)
 122                         git_config_from_file(submodule_config, gitmodules_path.buf, NULL);
 123                 strbuf_release(&gitmodules_path);
 124         }
 125 }
 126
 127 int parse_submodule_config_option(const char *var, const char *value)
 128 {
 129         int len;
 130         struct string_list_item *config;
 131         struct strbuf submodname = STRBUF_INIT;
 132
 133         var += 10;              /* Skip "submodule." */
 134
 135         len = strlen(var);
 136         if ((len > 5) && !strcmp(var + len - 5, ".path")) {
 137                 strbuf_add(&submodname, var, len - 5);
 138                 config = unsorted_string_list_lookup(&config_name_for_path, value);
 139                 if (config)
 140                         free(config->util);
 141                 else
 142                         config = string_list_append(&config_name_for_path, xstrdup(value));
 143                 config->util = strbuf_detach(&submodname, NULL);
 144                 strbuf_release(&submodname);
 145         } else if ((len > 23) && !strcmp(var + len - 23, ".fetchrecursesubmodules")) {
 146                 strbuf_add(&submodname, var, len - 23);
 147                 config = unsorted_string_list_lookup(&config_fetch_recurse_submodules_for_name, submodname.buf);
 148                 if (!config)
 149                         config = string_list_append(&config_fetch_recurse_submodules_for_name,
 150                                                     strbuf_detach(&submodname, NULL));
 151                 config->util = (void *)(intptr_t)parse_fetch_recurse_submodules_arg(var, value);
 152                 strbuf_release(&submodname);
 153         } else if ((len > 7) && !strcmp(var + len - 7, ".ignore")) {
 154                 if (strcmp(value, "untracked") && strcmp(value, "dirty") &&
 155                     strcmp(value, "all") && strcmp(value, "none")) {
 156                         warning("Invalid parameter \"%s\" for config option \"submodule.%s.ignore\"", value, var);
 157                         return 0;
 158                 }
 159
 160                 strbuf_add(&submodname, var, len - 7);
 161                 config = unsorted_string_list_lookup(&config_ignore_for_name, submodname.buf);
 162                 if (config)
 163                         free(config->util);
 164                 else
 165                         config = string_list_append(&config_ignore_for_name,
 166                                                     strbuf_detach(&submodname, NULL));
 167                 strbuf_release(&submodname);
 168                 config->util = xstrdup(value);
 169                 return 0;
 170         }
 171         return 0;
 172 }
 173
 174 void handle_ignore_submodules_arg(struct diff_options *diffopt,
 175                                   const char *arg)
 176 {
 177         DIFF_OPT_CLR(diffopt, IGNORE_SUBMODULES);
 178         DIFF_OPT_CLR(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 179         DIFF_OPT_CLR(diffopt, IGNORE_DIRTY_SUBMODULES);
 180
 181         if (!strcmp(arg, "all"))
 182                 DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
 183         else if (!strcmp(arg, "untracked"))
 184                 DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 185         else if (!strcmp(arg, "dirty"))
 186                 DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES);
 187         else if (strcmp(arg, "none"))
 188                 die("bad --ignore-submodules argument: %s", arg);
 189 }
 190
 191 static int prepare_submodule_summary(struct rev_info *rev, const char *path,
 192                 struct commit *left, struct commit *right,
 193                 int *fast_forward, int *fast_backward)
 194 {
 195         struct commit_list *merge_bases, *list;
 196
 197         init_revisions(rev, NULL);
 198         setup_revisions(0, NULL, rev, NULL);
 199         rev->left_right = 1;
 200         rev->first_parent_only = 1;
 201         left->object.flags |= SYMMETRIC_LEFT;
 202         add_pending_object(rev, &left->object, path);
 203         add_pending_object(rev, &right->object, path);
 204         merge_bases = get_merge_bases(left, right, 1);
 205         if (merge_bases) {
 206                 if (merge_bases->item == left)
 207                         *fast_forward = 1;
 208                 else if (merge_bases->item == right)
 209                         *fast_backward = 1;
 210         }
 211         for (list = merge_bases; list; list = list->next) {
 212                 list->item->object.flags |= UNINTERESTING;
 213                 add_pending_object(rev, &list->item->object,
 214                         sha1_to_hex(list->item->object.sha1));
 215         }
 216         return prepare_revision_walk(rev);
 217 }
 218
 219 static void print_submodule_summary(struct rev_info *rev, FILE *f,
 220                 const char *del, const char *add, const char *reset)
 221 {
 222         static const char format[] = "  %m %s";
 223         struct strbuf sb = STRBUF_INIT;
 224         struct commit *commit;
 225
 226         while ((commit = get_revision(rev))) {
 227                 struct pretty_print_context ctx = {0};
 228                 ctx.date_mode = rev->date_mode;
 229                 strbuf_setlen(&sb, 0);
 230                 if (commit->object.flags & SYMMETRIC_LEFT) {
 231                         if (del)
 232                                 strbuf_addstr(&sb, del);
 233                 }
 234                 else if (add)
 235                         strbuf_addstr(&sb, add);
 236                 format_commit_message(commit, format, &sb, &ctx);
 237                 if (reset)
 238                         strbuf_addstr(&sb, reset);
 239                 strbuf_addch(&sb, '\n');
 240                 fprintf(f, "%s", sb.buf);
 241         }
 242         strbuf_release(&sb);
 243 }
 244
 245 int parse_fetch_recurse_submodules_arg(const char *opt, const char *arg)
 246 {
 247         switch (git_config_maybe_bool(opt, arg)) {
 248         case 1:
 249                 return RECURSE_SUBMODULES_ON;
 250         case 0:
 251                 return RECURSE_SUBMODULES_OFF;
 252         default:
 253                 if (!strcmp(arg, "on-demand"))
 254                         return RECURSE_SUBMODULES_ON_DEMAND;
 255                 die("bad %s argument: %s", opt, arg);
 256         }
 257 }
 258
 259 void show_submodule_summary(FILE *f, const char *path,
 260                 unsigned char one[20], unsigned char two[20],
 261                 unsigned dirty_submodule,
 262                 const char *del, const char *add, const char *reset)
 263 {
 264         struct rev_info rev;
 265         struct commit *left = left, *right = right;
 266         const char *message = NULL;
 267         struct strbuf sb = STRBUF_INIT;
 268         int fast_forward = 0, fast_backward = 0;
 269
 270         if (is_null_sha1(two))
 271                 message = "(submodule deleted)";
 272         else if (add_submodule_odb(path))
 273                 message = "(not checked out)";
 274         else if (is_null_sha1(one))
 275                 message = "(new submodule)";
 276         else if (!(left = lookup_commit_reference(one)) ||
 277                  !(right = lookup_commit_reference(two)))
 278                 message = "(commits not present)";
 279
 280         if (!message &&
 281             prepare_submodule_summary(&rev, path, left, right,
 282                                         &fast_forward, &fast_backward))
 283                 message = "(revision walker failed)";
 284
 285         if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
 286                 fprintf(f, "Submodule %s contains untracked content\n", path);
 287         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
 288                 fprintf(f, "Submodule %s contains modified content\n", path);
 289
 290         if (!hashcmp(one, two)) {
 291                 strbuf_release(&sb);
 292                 return;
 293         }
 294
 295         strbuf_addf(&sb, "Submodule %s %s..", path,
 296                         find_unique_abbrev(one, DEFAULT_ABBREV));
 297         if (!fast_backward && !fast_forward)
 298                 strbuf_addch(&sb, '.');
 299         strbuf_addf(&sb, "%s", find_unique_abbrev(two, DEFAULT_ABBREV));
 300         if (message)
 301                 strbuf_addf(&sb, " %s\n", message);
 302         else
 303                 strbuf_addf(&sb, "%s:\n", fast_backward ? " (rewind)" : "");
 304         fwrite(sb.buf, sb.len, 1, f);
 305
 306         if (!message) {
 307                 print_submodule_summary(&rev, f, del, add, reset);
 308                 clear_commit_marks(left, ~0);
 309                 clear_commit_marks(right, ~0);
 310         }
 311
 312         strbuf_release(&sb);
 313 }
 314
 315 void set_config_fetch_recurse_submodules(int value)
 316 {
 317         config_fetch_recurse_submodules = value;
 318 }
 319
 320 static int has_remote(const char *refname, const unsigned char *sha1, int flags, void *cb_data)
 321 {
 322         return 1;
 323 }
 324
 325 static int submodule_needs_pushing(const char *path, const unsigned char sha1[20])
 326 {
 327         if (add_submodule_odb(path) || !lookup_commit_reference(sha1))
 328                 return 0;
 329
 330         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 331                 struct child_process cp;
 332                 const char *argv[] = {"rev-list", NULL, "--not", "--remotes", "-n", "1" , NULL};
 333                 struct strbuf buf = STRBUF_INIT;
 334                 int needs_pushing = 0;
 335
 336                 argv[1] = sha1_to_hex(sha1);
 337                 memset(&cp, 0, sizeof(cp));
 338                 cp.argv = argv;
 339                 cp.env = local_repo_env;
 340                 cp.git_cmd = 1;
 341                 cp.no_stdin = 1;
 342                 cp.out = -1;
 343                 cp.dir = path;
 344                 if (start_command(&cp))
 345                         die("Could not run 'git rev-list %s --not --remotes -n 1' command in submodule %s",
 346                                 sha1_to_hex(sha1), path);
 347                 if (strbuf_read(&buf, cp.out, 41))
 348                         needs_pushing = 1;
 349                 finish_command(&cp);
 350                 close(cp.out);
 351                 strbuf_release(&buf);
 352                 return needs_pushing;
 353         }
 354
 355         return 0;
 356 }
 357
 358 static void collect_submodules_from_diff(struct diff_queue_struct *q,
 359                                          struct diff_options *options,
 360                                          void *data)
 361 {
 362         int i;
 363         struct string_list *needs_pushing = data;
 364
 365         for (i = 0; i < q->nr; i++) {
 366                 struct diff_filepair *p = q->queue[i];
 367                 if (!S_ISGITLINK(p->two->mode))
 368                         continue;
 369                 if (submodule_needs_pushing(p->two->path, p->two->sha1))
 370                         string_list_insert(needs_pushing, p->two->path);
 371         }
 372 }
 373
 374 static void find_unpushed_submodule_commits(struct commit *commit,
 375                 struct string_list *needs_pushing)
 376 {
 377         struct rev_info rev;
 378
 379         init_revisions(&rev, NULL);
 380         rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
 381         rev.diffopt.format_callback = collect_submodules_from_diff;
 382         rev.diffopt.format_callback_data = needs_pushing;
 383         diff_tree_combined_merge(commit, 1, &rev);
 384 }
 385
 386 int find_unpushed_submodules(unsigned char new_sha1[20],
 387                 const char *remotes_name, struct string_list *needs_pushing)
 388 {
 389         struct rev_info rev;
 390         struct commit *commit;
 391         const char *argv[] = {NULL, NULL, "--not", "NULL", NULL};
 392         int argc = ARRAY_SIZE(argv) - 1;
 393         char *sha1_copy;
 394
 395         struct strbuf remotes_arg = STRBUF_INIT;
 396
 397         strbuf_addf(&remotes_arg, "--remotes=%s", remotes_name);
 398         init_revisions(&rev, NULL);
 399         sha1_copy = xstrdup(sha1_to_hex(new_sha1));
 400         argv[1] = sha1_copy;
 401         argv[3] = remotes_arg.buf;
 402         setup_revisions(argc, argv, &rev, NULL);
 403         if (prepare_revision_walk(&rev))
 404                 die("revision walk setup failed");
 405
 406         while ((commit = get_revision(&rev)) != NULL)
 407                 find_unpushed_submodule_commits(commit, needs_pushing);
 408
 409         reset_revision_walk();
 410         free(sha1_copy);
 411         strbuf_release(&remotes_arg);
 412
 413         return needs_pushing->nr;
 414 }
 415
 416 static int push_submodule(const char *path)
 417 {
 418         if (add_submodule_odb(path))
 419                 return 1;
 420
 421         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 422                 struct child_process cp;
 423                 const char *argv[] = {"push", NULL};
 424
 425                 memset(&cp, 0, sizeof(cp));
 426                 cp.argv = argv;
 427                 cp.env = local_repo_env;
 428                 cp.git_cmd = 1;
 429                 cp.no_stdin = 1;
 430                 cp.dir = path;
 431                 if (run_command(&cp))
 432                         return 0;
 433                 close(cp.out);
 434         }
 435
 436         return 1;
 437 }
 438
 439 int push_unpushed_submodules(unsigned char new_sha1[20], const char *remotes_name)
 440 {
 441         int i, ret = 1;
 442         struct string_list needs_pushing;
 443
 444         memset(&needs_pushing, 0, sizeof(struct string_list));
 445         needs_pushing.strdup_strings = 1;
 446
 447         if (!find_unpushed_submodules(new_sha1, remotes_name, &needs_pushing))
 448                 return 1;
 449
 450         for (i = 0; i < needs_pushing.nr; i++) {
 451                 const char *path = needs_pushing.items[i].string;
 452                 fprintf(stderr, "Pushing submodule '%s'\n", path);
 453                 if (!push_submodule(path)) {
 454                         fprintf(stderr, "Unable to push submodule '%s'\n", path);
 455                         ret = 0;
 456                 }
 457         }
 458
 459         string_list_clear(&needs_pushing, 0);
 460
 461         return ret;
 462 }
 463
 464 static int is_submodule_commit_present(const char *path, unsigned char sha1[20])
 465 {
 466         int is_present = 0;
 467         if (!add_submodule_odb(path) && lookup_commit_reference(sha1)) {
 468                 /* Even if the submodule is checked out and the commit is
 469                  * present, make sure it is reachable from a ref. */
 470                 struct child_process cp;
 471                 const char *argv[] = {"rev-list", "-n", "1", NULL, "--not", "--all", NULL};
 472                 struct strbuf buf = STRBUF_INIT;
 473
 474                 argv[3] = sha1_to_hex(sha1);
 475                 memset(&cp, 0, sizeof(cp));
 476                 cp.argv = argv;
 477                 cp.env = local_repo_env;
 478                 cp.git_cmd = 1;
 479                 cp.no_stdin = 1;
 480                 cp.out = -1;
 481                 cp.dir = path;
 482                 if (!run_command(&cp) && !strbuf_read(&buf, cp.out, 1024))
 483                         is_present = 1;
 484
 485                 close(cp.out);
 486                 strbuf_release(&buf);
 487         }
 488         return is_present;
 489 }
 490
 491 static void submodule_collect_changed_cb(struct diff_queue_struct *q,
 492                                          struct diff_options *options,
 493                                          void *data)
 494 {
 495         int i;
 496         for (i = 0; i < q->nr; i++) {
 497                 struct diff_filepair *p = q->queue[i];
 498                 if (!S_ISGITLINK(p->two->mode))
 499                         continue;
 500
 501                 if (S_ISGITLINK(p->one->mode)) {
 502                         /* NEEDSWORK: We should honor the name configured in
 503                          * the .gitmodules file of the commit we are examining
 504                          * here to be able to correctly follow submodules
 505                          * being moved around. */
 506                         struct string_list_item *path;
 507                         path = unsorted_string_list_lookup(&changed_submodule_paths, p->two->path);
 508                         if (!path && !is_submodule_commit_present(p->two->path, p->two->sha1))
 509                                 string_list_append(&changed_submodule_paths, xstrdup(p->two->path));
 510                 } else {
 511                         /* Submodule is new or was moved here */
 512                         /* NEEDSWORK: When the .git directories of submodules
 513                          * live inside the superprojects .git directory some
 514                          * day we should fetch new submodules directly into
 515                          * that location too when config or options request
 516                          * that so they can be checked out from there. */
 517                         continue;
 518                 }
 519         }
 520 }
 521
 522 static int add_sha1_to_array(const char *ref, const unsigned char *sha1,
 523                              int flags, void *data)
 524 {
 525         sha1_array_append(data, sha1);
 526         return 0;
 527 }
 528
 529 void check_for_new_submodule_commits(unsigned char new_sha1[20])
 530 {
 531         if (!initialized_fetch_ref_tips) {
 532                 for_each_ref(add_sha1_to_array, &ref_tips_before_fetch);
 533                 initialized_fetch_ref_tips = 1;
 534         }
 535
 536         sha1_array_append(&ref_tips_after_fetch, new_sha1);
 537 }
 538
 539 static void add_sha1_to_argv(const unsigned char sha1[20], void *data)
 540 {
 541         argv_array_push(data, sha1_to_hex(sha1));
 542 }
 543
 544 static void calculate_changed_submodule_paths(void)
 545 {
 546         struct rev_info rev;
 547         struct commit *commit;
 548         struct argv_array argv = ARGV_ARRAY_INIT;
 549
 550         /* No need to check if there are no submodules configured */
 551         if (!config_name_for_path.nr)
 552                 return;
 553
 554         init_revisions(&rev, NULL);
 555         argv_array_push(&argv, "--"); /* argv[0] program name */
 556         sha1_array_for_each_unique(&ref_tips_after_fetch,
 557                                    add_sha1_to_argv, &argv);
 558         argv_array_push(&argv, "--not");
 559         sha1_array_for_each_unique(&ref_tips_before_fetch,
 560                                    add_sha1_to_argv, &argv);
 561         setup_revisions(argv.argc, argv.argv, &rev, NULL);
 562         if (prepare_revision_walk(&rev))
 563                 die("revision walk setup failed");
 564
 565         /*
 566          * Collect all submodules (whether checked out or not) for which new
 567          * commits have been recorded upstream in "changed_submodule_paths".
 568          */
 569         while ((commit = get_revision(&rev))) {
 570                 struct commit_list *parent = commit->parents;
 571                 while (parent) {
 572                         struct diff_options diff_opts;
 573                         diff_setup(&diff_opts);
 574                         DIFF_OPT_SET(&diff_opts, RECURSIVE);
 575                         diff_opts.output_format |= DIFF_FORMAT_CALLBACK;
 576                         diff_opts.format_callback = submodule_collect_changed_cb;
 577                         diff_setup_done(&diff_opts);
 578                         diff_tree_sha1(parent->item->object.sha1, commit->object.sha1, "", &diff_opts);
 579                         diffcore_std(&diff_opts);
 580                         diff_flush(&diff_opts);
 581                         parent = parent->next;
 582                 }
 583         }
 584
 585         argv_array_clear(&argv);
 586         sha1_array_clear(&ref_tips_before_fetch);
 587         sha1_array_clear(&ref_tips_after_fetch);
 588         initialized_fetch_ref_tips = 0;
 589 }
 590
 591 int fetch_populated_submodules(int num_options, const char **options,
 592                                const char *prefix, int command_line_option,
 593                                int quiet)
 594 {
 595         int i, result = 0, argc = 0, default_argc;
 596         struct child_process cp;
 597         const char **argv;
 598         struct string_list_item *name_for_path;
 599         const char *work_tree = get_git_work_tree();
 600         if (!work_tree)
 601                 goto out;
 602
 603         if (!the_index.initialized)
 604                 if (read_cache() < 0)
 605                         die("index file corrupt");
 606
 607         /* 6: "fetch" (options) --recurse-submodules-default default "--submodule-prefix" prefix NULL */
 608         argv = xcalloc(num_options + 6, sizeof(const char *));
 609         argv[argc++] = "fetch";
 610         for (i = 0; i < num_options; i++)
 611                 argv[argc++] = options[i];
 612         argv[argc++] = "--recurse-submodules-default";
 613         default_argc = argc++;
 614         argv[argc++] = "--submodule-prefix";
 615
 616         memset(&cp, 0, sizeof(cp));
 617         cp.argv = argv;
 618         cp.env = local_repo_env;
 619         cp.git_cmd = 1;
 620         cp.no_stdin = 1;
 621
 622         calculate_changed_submodule_paths();
 623
 624         for (i = 0; i < active_nr; i++) {
 625                 struct strbuf submodule_path = STRBUF_INIT;
 626                 struct strbuf submodule_git_dir = STRBUF_INIT;
 627                 struct strbuf submodule_prefix = STRBUF_INIT;
 628                 struct cache_entry *ce = active_cache[i];
 629                 const char *git_dir, *name, *default_argv;
 630
 631                 if (!S_ISGITLINK(ce->ce_mode))
 632                         continue;
 633
 634                 name = ce->name;
 635                 name_for_path = unsorted_string_list_lookup(&config_name_for_path, ce->name);
 636                 if (name_for_path)
 637                         name = name_for_path->util;
 638
 639                 default_argv = "yes";
 640                 if (command_line_option == RECURSE_SUBMODULES_DEFAULT) {
 641                         struct string_list_item *fetch_recurse_submodules_option;
 642                         fetch_recurse_submodules_option = unsorted_string_list_lookup(&config_fetch_recurse_submodules_for_name, name);
 643                         if (fetch_recurse_submodules_option) {
 644                                 if ((intptr_t)fetch_recurse_submodules_option->util == RECURSE_SUBMODULES_OFF)
 645                                         continue;
 646                                 if ((intptr_t)fetch_recurse_submodules_option->util == RECURSE_SUBMODULES_ON_DEMAND) {
 647                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 648                                                 continue;
 649                                         default_argv = "on-demand";
 650                                 }
 651                         } else {
 652                                 if ((config_fetch_recurse_submodules == RECURSE_SUBMODULES_OFF) ||
 653                                     gitmodules_is_unmerged)
 654                                         continue;
 655                                 if (config_fetch_recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) {
 656                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 657                                                 continue;
 658                                         default_argv = "on-demand";
 659                                 }
 660                         }
 661                 } else if (command_line_option == RECURSE_SUBMODULES_ON_DEMAND) {
 662                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 663                                 continue;
 664                         default_argv = "on-demand";
 665                 }
 666
 667                 strbuf_addf(&submodule_path, "%s/%s", work_tree, ce->name);
 668                 strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
 669                 strbuf_addf(&submodule_prefix, "%s%s/", prefix, ce->name);
 670                 git_dir = read_gitfile(submodule_git_dir.buf);
 671                 if (!git_dir)
 672                         git_dir = submodule_git_dir.buf;
 673                 if (is_directory(git_dir)) {
 674                         if (!quiet)
 675                                 printf("Fetching submodule %s%s\n", prefix, ce->name);
 676                         cp.dir = submodule_path.buf;
 677                         argv[default_argc] = default_argv;
 678                         argv[argc] = submodule_prefix.buf;
 679                         if (run_command(&cp))
 680                                 result = 1;
 681                 }
 682                 strbuf_release(&submodule_path);
 683                 strbuf_release(&submodule_git_dir);
 684                 strbuf_release(&submodule_prefix);
 685         }
 686         free(argv);
 687 out:
 688         string_list_clear(&changed_submodule_paths, 1);
 689         return result;
 690 }
 691
 692 unsigned is_submodule_modified(const char *path, int ignore_untracked)
 693 {
 694         ssize_t len;
 695         struct child_process cp;
 696         const char *argv[] = {
 697                 "status",
 698                 "--porcelain",
 699                 NULL,
 700                 NULL,
 701         };
 702         struct strbuf buf = STRBUF_INIT;
 703         unsigned dirty_submodule = 0;
 704         const char *line, *next_line;
 705         const char *git_dir;
 706
 707         strbuf_addf(&buf, "%s/.git", path);
 708         git_dir = read_gitfile(buf.buf);
 709         if (!git_dir)
 710                 git_dir = buf.buf;
 711         if (!is_directory(git_dir)) {
 712                 strbuf_release(&buf);
 713                 /* The submodule is not checked out, so it is not modified */
 714                 return 0;
 715
 716         }
 717         strbuf_reset(&buf);
 718
 719         if (ignore_untracked)
 720                 argv[2] = "-uno";
 721
 722         memset(&cp, 0, sizeof(cp));
 723         cp.argv = argv;
 724         cp.env = local_repo_env;
 725         cp.git_cmd = 1;
 726         cp.no_stdin = 1;
 727         cp.out = -1;
 728         cp.dir = path;
 729         if (start_command(&cp))
 730                 die("Could not run 'git status --porcelain' in submodule %s", path);
 731
 732         len = strbuf_read(&buf, cp.out, 1024);
 733         line = buf.buf;
 734         while (len > 2) {
 735                 if ((line[0] == '?') && (line[1] == '?')) {
 736                         dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
 737                         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
 738                                 break;
 739                 } else {
 740                         dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
 741                         if (ignore_untracked ||
 742                             (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED))
 743                                 break;
 744                 }
 745                 next_line = strchr(line, '\n');
 746                 if (!next_line)
 747                         break;
 748                 next_line++;
 749                 len -= (next_line - line);
 750                 line = next_line;
 751         }
 752         close(cp.out);
 753
 754         if (finish_command(&cp))
 755                 die("'git status --porcelain' failed in submodule %s", path);
 756
 757         strbuf_release(&buf);
 758         return dirty_submodule;
 759 }
 760
 761 static int find_first_merges(struct object_array *result, const char *path,
 762                 struct commit *a, struct commit *b)
 763 {
 764         int i, j;
 765         struct object_array merges;
 766         struct commit *commit;
 767         int contains_another;
 768
 769         char merged_revision[42];
 770         const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
 771                                    "--all", merged_revision, NULL };
 772         struct rev_info revs;
 773         struct setup_revision_opt rev_opts;
 774
 775         memset(&merges, 0, sizeof(merges));
 776         memset(result, 0, sizeof(struct object_array));
 777         memset(&rev_opts, 0, sizeof(rev_opts));
 778
 779         /* get all revisions that merge commit a */
 780         snprintf(merged_revision, sizeof(merged_revision), "^%s",
 781                         sha1_to_hex(a->object.sha1));
 782         init_revisions(&revs, NULL);
 783         rev_opts.submodule = path;
 784         setup_revisions(sizeof(rev_args)/sizeof(char *)-1, rev_args, &revs, &rev_opts);
 785
 786         /* save all revisions from the above list that contain b */
 787         if (prepare_revision_walk(&revs))
 788                 die("revision walk setup failed");
 789         while ((commit = get_revision(&revs)) != NULL) {
 790                 struct object *o = &(commit->object);
 791                 if (in_merge_bases(b, &commit, 1))
 792                         add_object_array(o, NULL, &merges);
 793         }
 794         reset_revision_walk();
 795
 796         /* Now we've got all merges that contain a and b. Prune all
 797          * merges that contain another found merge and save them in
 798          * result.
 799          */
 800         for (i = 0; i < merges.nr; i++) {
 801                 struct commit *m1 = (struct commit *) merges.objects[i].item;
 802
 803                 contains_another = 0;
 804                 for (j = 0; j < merges.nr; j++) {
 805                         struct commit *m2 = (struct commit *) merges.objects[j].item;
 806                         if (i != j && in_merge_bases(m2, &m1, 1)) {
 807                                 contains_another = 1;
 808                                 break;
 809                         }
 810                 }
 811
 812                 if (!contains_another)
 813                         add_object_array(merges.objects[i].item,
 814                                          merges.objects[i].name, result);
 815         }
 816
 817         free(merges.objects);
 818         return result->nr;
 819 }
 820
 821 static void print_commit(struct commit *commit)
 822 {
 823         struct strbuf sb = STRBUF_INIT;
 824         struct pretty_print_context ctx = {0};
 825         ctx.date_mode = DATE_NORMAL;
 826         format_commit_message(commit, " %h: %m %s", &sb, &ctx);
 827         fprintf(stderr, "%s\n", sb.buf);
 828         strbuf_release(&sb);
 829 }
 830
 831 #define MERGE_WARNING(path, msg) \
 832         warning("Failed to merge submodule %s (%s)", path, msg);
 833
 834 int merge_submodule(unsigned char result[20], const char *path,
 835                     const unsigned char base[20], const unsigned char a[20],
 836                     const unsigned char b[20], int search)
 837 {
 838         struct commit *commit_base, *commit_a, *commit_b;
 839         int parent_count;
 840         struct object_array merges;
 841
 842         int i;
 843
 844         /* store a in result in case we fail */
 845         hashcpy(result, a);
 846
 847         /* we can not handle deletion conflicts */
 848         if (is_null_sha1(base))
 849                 return 0;
 850         if (is_null_sha1(a))
 851                 return 0;
 852         if (is_null_sha1(b))
 853                 return 0;
 854
 855         if (add_submodule_odb(path)) {
 856                 MERGE_WARNING(path, "not checked out");
 857                 return 0;
 858         }
 859
 860         if (!(commit_base = lookup_commit_reference(base)) ||
 861             !(commit_a = lookup_commit_reference(a)) ||
 862             !(commit_b = lookup_commit_reference(b))) {
 863                 MERGE_WARNING(path, "commits not present");
 864                 return 0;
 865         }
 866
 867         /* check whether both changes are forward */
 868         if (!in_merge_bases(commit_base, &commit_a, 1) ||
 869             !in_merge_bases(commit_base, &commit_b, 1)) {
 870                 MERGE_WARNING(path, "commits don't follow merge-base");
 871                 return 0;
 872         }
 873
 874         /* Case #1: a is contained in b or vice versa */
 875         if (in_merge_bases(commit_a, &commit_b, 1)) {
 876                 hashcpy(result, b);
 877                 return 1;
 878         }
 879         if (in_merge_bases(commit_b, &commit_a, 1)) {
 880                 hashcpy(result, a);
 881                 return 1;
 882         }
 883
 884         /*
 885          * Case #2: There are one or more merges that contain a and b in
 886          * the submodule. If there is only one, then present it as a
 887          * suggestion to the user, but leave it marked unmerged so the
 888          * user needs to confirm the resolution.
 889          */
 890
 891         /* Skip the search if makes no sense to the calling context.  */
 892         if (!search)
 893                 return 0;
 894
 895         /* find commit which merges them */
 896         parent_count = find_first_merges(&merges, path, commit_a, commit_b);
 897         switch (parent_count) {
 898         case 0:
 899                 MERGE_WARNING(path, "merge following commits not found");
 900                 break;
 901
 902         case 1:
 903                 MERGE_WARNING(path, "not fast-forward");
 904                 fprintf(stderr, "Found a possible merge resolution "
 905                                 "for the submodule:\n");
 906                 print_commit((struct commit *) merges.objects[0].item);
 907                 fprintf(stderr,
 908                         "If this is correct simply add it to the index "
 909                         "for example\n"
 910                         "by using:\n\n"
 911                         "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
 912                         "which will accept this suggestion.\n",
 913                         sha1_to_hex(merges.objects[0].item->sha1), path);
 914                 break;
 915
 916         default:
 917                 MERGE_WARNING(path, "multiple merges found");
 918                 for (i = 0; i < merges.nr; i++)
 919                         print_commit((struct commit *) merges.objects[i].item);
 920         }
 921
 922         free(merges.objects);
 923         return 0;
 924 }