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         struct string_list_item *config;
 130         const char *name, *key;
 131         int namelen;
 132
 133         if (parse_config_key(var, "submodule", &name, &namelen, &key) < 0 || !name)
 134                 return 0;
 135
 136         if (!strcmp(key, "path")) {
 137                 if (!value)
 138                         return config_error_nonbool(var);
 139
 140                 config = unsorted_string_list_lookup(&config_name_for_path, value);
 141                 if (config)
 142                         free(config->util);
 143                 else
 144                         config = string_list_append(&config_name_for_path, xstrdup(value));
 145                 config->util = xmemdupz(name, namelen);
 146         } else if (!strcmp(key, "fetchrecursesubmodules")) {
 147                 char *name_cstr = xmemdupz(name, namelen);
 148                 config = unsorted_string_list_lookup(&config_fetch_recurse_submodules_for_name, name_cstr);
 149                 if (!config)
 150                         config = string_list_append(&config_fetch_recurse_submodules_for_name, name_cstr);
 151                 else
 152                         free(name_cstr);
 153                 config->util = (void *)(intptr_t)parse_fetch_recurse_submodules_arg(var, value);
 154         } else if (!strcmp(key, "ignore")) {
 155                 char *name_cstr;
 156
 157                 if (!value)
 158                         return config_error_nonbool(var);
 159
 160                 if (strcmp(value, "untracked") && strcmp(value, "dirty") &&
 161                     strcmp(value, "all") && strcmp(value, "none")) {
 162                         warning("Invalid parameter \"%s\" for config option \"submodule.%s.ignore\"", value, var);
 163                         return 0;
 164                 }
 165
 166                 name_cstr = xmemdupz(name, namelen);
 167                 config = unsorted_string_list_lookup(&config_ignore_for_name, name_cstr);
 168                 if (config) {
 169                         free(config->util);
 170                         free(name_cstr);
 171                 } else
 172                         config = string_list_append(&config_ignore_for_name, name_cstr);
 173                 config->util = xstrdup(value);
 174                 return 0;
 175         }
 176         return 0;
 177 }
 178
 179 void handle_ignore_submodules_arg(struct diff_options *diffopt,
 180                                   const char *arg)
 181 {
 182         DIFF_OPT_CLR(diffopt, IGNORE_SUBMODULES);
 183         DIFF_OPT_CLR(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 184         DIFF_OPT_CLR(diffopt, IGNORE_DIRTY_SUBMODULES);
 185
 186         if (!strcmp(arg, "all"))
 187                 DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
 188         else if (!strcmp(arg, "untracked"))
 189                 DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 190         else if (!strcmp(arg, "dirty"))
 191                 DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES);
 192         else if (strcmp(arg, "none"))
 193                 die("bad --ignore-submodules argument: %s", arg);
 194 }
 195
 196 static int prepare_submodule_summary(struct rev_info *rev, const char *path,
 197                 struct commit *left, struct commit *right,
 198                 int *fast_forward, int *fast_backward)
 199 {
 200         struct commit_list *merge_bases, *list;
 201
 202         init_revisions(rev, NULL);
 203         setup_revisions(0, NULL, rev, NULL);
 204         rev->left_right = 1;
 205         rev->first_parent_only = 1;
 206         left->object.flags |= SYMMETRIC_LEFT;
 207         add_pending_object(rev, &left->object, path);
 208         add_pending_object(rev, &right->object, path);
 209         merge_bases = get_merge_bases(left, right, 1);
 210         if (merge_bases) {
 211                 if (merge_bases->item == left)
 212                         *fast_forward = 1;
 213                 else if (merge_bases->item == right)
 214                         *fast_backward = 1;
 215         }
 216         for (list = merge_bases; list; list = list->next) {
 217                 list->item->object.flags |= UNINTERESTING;
 218                 add_pending_object(rev, &list->item->object,
 219                         sha1_to_hex(list->item->object.sha1));
 220         }
 221         return prepare_revision_walk(rev);
 222 }
 223
 224 static void print_submodule_summary(struct rev_info *rev, FILE *f,
 225                 const char *del, const char *add, const char *reset)
 226 {
 227         static const char format[] = "  %m %s";
 228         struct strbuf sb = STRBUF_INIT;
 229         struct commit *commit;
 230
 231         while ((commit = get_revision(rev))) {
 232                 struct pretty_print_context ctx = {0};
 233                 ctx.date_mode = rev->date_mode;
 234                 strbuf_setlen(&sb, 0);
 235                 if (commit->object.flags & SYMMETRIC_LEFT) {
 236                         if (del)
 237                                 strbuf_addstr(&sb, del);
 238                 }
 239                 else if (add)
 240                         strbuf_addstr(&sb, add);
 241                 format_commit_message(commit, format, &sb, &ctx);
 242                 if (reset)
 243                         strbuf_addstr(&sb, reset);
 244                 strbuf_addch(&sb, '\n');
 245                 fprintf(f, "%s", sb.buf);
 246         }
 247         strbuf_release(&sb);
 248 }
 249
 250 int parse_fetch_recurse_submodules_arg(const char *opt, const char *arg)
 251 {
 252         switch (git_config_maybe_bool(opt, arg)) {
 253         case 1:
 254                 return RECURSE_SUBMODULES_ON;
 255         case 0:
 256                 return RECURSE_SUBMODULES_OFF;
 257         default:
 258                 if (!strcmp(arg, "on-demand"))
 259                         return RECURSE_SUBMODULES_ON_DEMAND;
 260                 die("bad %s argument: %s", opt, arg);
 261         }
 262 }
 263
 264 void show_submodule_summary(FILE *f, const char *path,
 265                 unsigned char one[20], unsigned char two[20],
 266                 unsigned dirty_submodule, const char *meta,
 267                 const char *del, const char *add, const char *reset)
 268 {
 269         struct rev_info rev;
 270         struct commit *left = NULL, *right = NULL;
 271         const char *message = NULL;
 272         struct strbuf sb = STRBUF_INIT;
 273         int fast_forward = 0, fast_backward = 0;
 274
 275         if (is_null_sha1(two))
 276                 message = "(submodule deleted)";
 277         else if (add_submodule_odb(path))
 278                 message = "(not checked out)";
 279         else if (is_null_sha1(one))
 280                 message = "(new submodule)";
 281         else if (!(left = lookup_commit_reference(one)) ||
 282                  !(right = lookup_commit_reference(two)))
 283                 message = "(commits not present)";
 284         else if (prepare_submodule_summary(&rev, path, left, right,
 285                                            &fast_forward, &fast_backward))
 286                 message = "(revision walker failed)";
 287
 288         if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
 289                 fprintf(f, "Submodule %s contains untracked content\n", path);
 290         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
 291                 fprintf(f, "Submodule %s contains modified content\n", path);
 292
 293         if (!hashcmp(one, two)) {
 294                 strbuf_release(&sb);
 295                 return;
 296         }
 297
 298         strbuf_addf(&sb, "%sSubmodule %s %s..", meta, path,
 299                         find_unique_abbrev(one, DEFAULT_ABBREV));
 300         if (!fast_backward && !fast_forward)
 301                 strbuf_addch(&sb, '.');
 302         strbuf_addf(&sb, "%s", find_unique_abbrev(two, DEFAULT_ABBREV));
 303         if (message)
 304                 strbuf_addf(&sb, " %s%s\n", message, reset);
 305         else
 306                 strbuf_addf(&sb, "%s:%s\n", fast_backward ? " (rewind)" : "", reset);
 307         fwrite(sb.buf, sb.len, 1, f);
 308
 309         if (!message) /* only NULL if we succeeded in setting up the walk */
 310                 print_submodule_summary(&rev, f, del, add, reset);
 311         if (left)
 312                 clear_commit_marks(left, ~0);
 313         if (right)
 314                 clear_commit_marks(right, ~0);
 315
 316         strbuf_release(&sb);
 317 }
 318
 319 void set_config_fetch_recurse_submodules(int value)
 320 {
 321         config_fetch_recurse_submodules = value;
 322 }
 323
 324 static int has_remote(const char *refname, const unsigned char *sha1, int flags, void *cb_data)
 325 {
 326         return 1;
 327 }
 328
 329 static int submodule_needs_pushing(const char *path, const unsigned char sha1[20])
 330 {
 331         if (add_submodule_odb(path) || !lookup_commit_reference(sha1))
 332                 return 0;
 333
 334         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 335                 struct child_process cp;
 336                 const char *argv[] = {"rev-list", NULL, "--not", "--remotes", "-n", "1" , NULL};
 337                 struct strbuf buf = STRBUF_INIT;
 338                 int needs_pushing = 0;
 339
 340                 argv[1] = sha1_to_hex(sha1);
 341                 memset(&cp, 0, sizeof(cp));
 342                 cp.argv = argv;
 343                 cp.env = local_repo_env;
 344                 cp.git_cmd = 1;
 345                 cp.no_stdin = 1;
 346                 cp.out = -1;
 347                 cp.dir = path;
 348                 if (start_command(&cp))
 349                         die("Could not run 'git rev-list %s --not --remotes -n 1' command in submodule %s",
 350                                 sha1_to_hex(sha1), path);
 351                 if (strbuf_read(&buf, cp.out, 41))
 352                         needs_pushing = 1;
 353                 finish_command(&cp);
 354                 close(cp.out);
 355                 strbuf_release(&buf);
 356                 return needs_pushing;
 357         }
 358
 359         return 0;
 360 }
 361
 362 static void collect_submodules_from_diff(struct diff_queue_struct *q,
 363                                          struct diff_options *options,
 364                                          void *data)
 365 {
 366         int i;
 367         struct string_list *needs_pushing = data;
 368
 369         for (i = 0; i < q->nr; i++) {
 370                 struct diff_filepair *p = q->queue[i];
 371                 if (!S_ISGITLINK(p->two->mode))
 372                         continue;
 373                 if (submodule_needs_pushing(p->two->path, p->two->sha1))
 374                         string_list_insert(needs_pushing, p->two->path);
 375         }
 376 }
 377
 378 static void find_unpushed_submodule_commits(struct commit *commit,
 379                 struct string_list *needs_pushing)
 380 {
 381         struct rev_info rev;
 382
 383         init_revisions(&rev, NULL);
 384         rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
 385         rev.diffopt.format_callback = collect_submodules_from_diff;
 386         rev.diffopt.format_callback_data = needs_pushing;
 387         diff_tree_combined_merge(commit, 1, &rev);
 388 }
 389
 390 int find_unpushed_submodules(unsigned char new_sha1[20],
 391                 const char *remotes_name, struct string_list *needs_pushing)
 392 {
 393         struct rev_info rev;
 394         struct commit *commit;
 395         const char *argv[] = {NULL, NULL, "--not", "NULL", NULL};
 396         int argc = ARRAY_SIZE(argv) - 1;
 397         char *sha1_copy;
 398
 399         struct strbuf remotes_arg = STRBUF_INIT;
 400
 401         strbuf_addf(&remotes_arg, "--remotes=%s", remotes_name);
 402         init_revisions(&rev, NULL);
 403         sha1_copy = xstrdup(sha1_to_hex(new_sha1));
 404         argv[1] = sha1_copy;
 405         argv[3] = remotes_arg.buf;
 406         setup_revisions(argc, argv, &rev, NULL);
 407         if (prepare_revision_walk(&rev))
 408                 die("revision walk setup failed");
 409
 410         while ((commit = get_revision(&rev)) != NULL)
 411                 find_unpushed_submodule_commits(commit, needs_pushing);
 412
 413         reset_revision_walk();
 414         free(sha1_copy);
 415         strbuf_release(&remotes_arg);
 416
 417         return needs_pushing->nr;
 418 }
 419
 420 static int push_submodule(const char *path)
 421 {
 422         if (add_submodule_odb(path))
 423                 return 1;
 424
 425         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 426                 struct child_process cp;
 427                 const char *argv[] = {"push", NULL};
 428
 429                 memset(&cp, 0, sizeof(cp));
 430                 cp.argv = argv;
 431                 cp.env = local_repo_env;
 432                 cp.git_cmd = 1;
 433                 cp.no_stdin = 1;
 434                 cp.dir = path;
 435                 if (run_command(&cp))
 436                         return 0;
 437                 close(cp.out);
 438         }
 439
 440         return 1;
 441 }
 442
 443 int push_unpushed_submodules(unsigned char new_sha1[20], const char *remotes_name)
 444 {
 445         int i, ret = 1;
 446         struct string_list needs_pushing;
 447
 448         memset(&needs_pushing, 0, sizeof(struct string_list));
 449         needs_pushing.strdup_strings = 1;
 450
 451         if (!find_unpushed_submodules(new_sha1, remotes_name, &needs_pushing))
 452                 return 1;
 453
 454         for (i = 0; i < needs_pushing.nr; i++) {
 455                 const char *path = needs_pushing.items[i].string;
 456                 fprintf(stderr, "Pushing submodule '%s'\n", path);
 457                 if (!push_submodule(path)) {
 458                         fprintf(stderr, "Unable to push submodule '%s'\n", path);
 459                         ret = 0;
 460                 }
 461         }
 462
 463         string_list_clear(&needs_pushing, 0);
 464
 465         return ret;
 466 }
 467
 468 static int is_submodule_commit_present(const char *path, unsigned char sha1[20])
 469 {
 470         int is_present = 0;
 471         if (!add_submodule_odb(path) && lookup_commit_reference(sha1)) {
 472                 /* Even if the submodule is checked out and the commit is
 473                  * present, make sure it is reachable from a ref. */
 474                 struct child_process cp;
 475                 const char *argv[] = {"rev-list", "-n", "1", NULL, "--not", "--all", NULL};
 476                 struct strbuf buf = STRBUF_INIT;
 477
 478                 argv[3] = sha1_to_hex(sha1);
 479                 memset(&cp, 0, sizeof(cp));
 480                 cp.argv = argv;
 481                 cp.env = local_repo_env;
 482                 cp.git_cmd = 1;
 483                 cp.no_stdin = 1;
 484                 cp.out = -1;
 485                 cp.dir = path;
 486                 if (!run_command(&cp) && !strbuf_read(&buf, cp.out, 1024))
 487                         is_present = 1;
 488
 489                 close(cp.out);
 490                 strbuf_release(&buf);
 491         }
 492         return is_present;
 493 }
 494
 495 static void submodule_collect_changed_cb(struct diff_queue_struct *q,
 496                                          struct diff_options *options,
 497                                          void *data)
 498 {
 499         int i;
 500         for (i = 0; i < q->nr; i++) {
 501                 struct diff_filepair *p = q->queue[i];
 502                 if (!S_ISGITLINK(p->two->mode))
 503                         continue;
 504
 505                 if (S_ISGITLINK(p->one->mode)) {
 506                         /* NEEDSWORK: We should honor the name configured in
 507                          * the .gitmodules file of the commit we are examining
 508                          * here to be able to correctly follow submodules
 509                          * being moved around. */
 510                         struct string_list_item *path;
 511                         path = unsorted_string_list_lookup(&changed_submodule_paths, p->two->path);
 512                         if (!path && !is_submodule_commit_present(p->two->path, p->two->sha1))
 513                                 string_list_append(&changed_submodule_paths, xstrdup(p->two->path));
 514                 } else {
 515                         /* Submodule is new or was moved here */
 516                         /* NEEDSWORK: When the .git directories of submodules
 517                          * live inside the superprojects .git directory some
 518                          * day we should fetch new submodules directly into
 519                          * that location too when config or options request
 520                          * that so they can be checked out from there. */
 521                         continue;
 522                 }
 523         }
 524 }
 525
 526 static int add_sha1_to_array(const char *ref, const unsigned char *sha1,
 527                              int flags, void *data)
 528 {
 529         sha1_array_append(data, sha1);
 530         return 0;
 531 }
 532
 533 void check_for_new_submodule_commits(unsigned char new_sha1[20])
 534 {
 535         if (!initialized_fetch_ref_tips) {
 536                 for_each_ref(add_sha1_to_array, &ref_tips_before_fetch);
 537                 initialized_fetch_ref_tips = 1;
 538         }
 539
 540         sha1_array_append(&ref_tips_after_fetch, new_sha1);
 541 }
 542
 543 static void add_sha1_to_argv(const unsigned char sha1[20], void *data)
 544 {
 545         argv_array_push(data, sha1_to_hex(sha1));
 546 }
 547
 548 static void calculate_changed_submodule_paths(void)
 549 {
 550         struct rev_info rev;
 551         struct commit *commit;
 552         struct argv_array argv = ARGV_ARRAY_INIT;
 553
 554         /* No need to check if there are no submodules configured */
 555         if (!config_name_for_path.nr)
 556                 return;
 557
 558         init_revisions(&rev, NULL);
 559         argv_array_push(&argv, "--"); /* argv[0] program name */
 560         sha1_array_for_each_unique(&ref_tips_after_fetch,
 561                                    add_sha1_to_argv, &argv);
 562         argv_array_push(&argv, "--not");
 563         sha1_array_for_each_unique(&ref_tips_before_fetch,
 564                                    add_sha1_to_argv, &argv);
 565         setup_revisions(argv.argc, argv.argv, &rev, NULL);
 566         if (prepare_revision_walk(&rev))
 567                 die("revision walk setup failed");
 568
 569         /*
 570          * Collect all submodules (whether checked out or not) for which new
 571          * commits have been recorded upstream in "changed_submodule_paths".
 572          */
 573         while ((commit = get_revision(&rev))) {
 574                 struct commit_list *parent = commit->parents;
 575                 while (parent) {
 576                         struct diff_options diff_opts;
 577                         diff_setup(&diff_opts);
 578                         DIFF_OPT_SET(&diff_opts, RECURSIVE);
 579                         diff_opts.output_format |= DIFF_FORMAT_CALLBACK;
 580                         diff_opts.format_callback = submodule_collect_changed_cb;
 581                         diff_setup_done(&diff_opts);
 582                         diff_tree_sha1(parent->item->object.sha1, commit->object.sha1, "", &diff_opts);
 583                         diffcore_std(&diff_opts);
 584                         diff_flush(&diff_opts);
 585                         parent = parent->next;
 586                 }
 587         }
 588
 589         argv_array_clear(&argv);
 590         sha1_array_clear(&ref_tips_before_fetch);
 591         sha1_array_clear(&ref_tips_after_fetch);
 592         initialized_fetch_ref_tips = 0;
 593 }
 594
 595 int fetch_populated_submodules(const struct argv_array *options,
 596                                const char *prefix, int command_line_option,
 597                                int quiet)
 598 {
 599         int i, result = 0;
 600         struct child_process cp;
 601         struct argv_array argv = ARGV_ARRAY_INIT;
 602         struct string_list_item *name_for_path;
 603         const char *work_tree = get_git_work_tree();
 604         if (!work_tree)
 605                 goto out;
 606
 607         if (!the_index.initialized)
 608                 if (read_cache() < 0)
 609                         die("index file corrupt");
 610
 611         argv_array_push(&argv, "fetch");
 612         for (i = 0; i < options->argc; i++)
 613                 argv_array_push(&argv, options->argv[i]);
 614         argv_array_push(&argv, "--recurse-submodules-default");
 615         /* default value, "--submodule-prefix" and its value are added later */
 616
 617         memset(&cp, 0, sizeof(cp));
 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_array_push(&argv, default_argv);
 678                         argv_array_push(&argv, "--submodule-prefix");
 679                         argv_array_push(&argv, submodule_prefix.buf);
 680                         cp.argv = argv.argv;
 681                         if (run_command(&cp))
 682                                 result = 1;
 683                         argv_array_pop(&argv);
 684                         argv_array_pop(&argv);
 685                         argv_array_pop(&argv);
 686                 }
 687                 strbuf_release(&submodule_path);
 688                 strbuf_release(&submodule_git_dir);
 689                 strbuf_release(&submodule_prefix);
 690         }
 691         argv_array_clear(&argv);
 692 out:
 693         string_list_clear(&changed_submodule_paths, 1);
 694         return result;
 695 }
 696
 697 unsigned is_submodule_modified(const char *path, int ignore_untracked)
 698 {
 699         ssize_t len;
 700         struct child_process cp;
 701         const char *argv[] = {
 702                 "status",
 703                 "--porcelain",
 704                 NULL,
 705                 NULL,
 706         };
 707         struct strbuf buf = STRBUF_INIT;
 708         unsigned dirty_submodule = 0;
 709         const char *line, *next_line;
 710         const char *git_dir;
 711
 712         strbuf_addf(&buf, "%s/.git", path);
 713         git_dir = read_gitfile(buf.buf);
 714         if (!git_dir)
 715                 git_dir = buf.buf;
 716         if (!is_directory(git_dir)) {
 717                 strbuf_release(&buf);
 718                 /* The submodule is not checked out, so it is not modified */
 719                 return 0;
 720
 721         }
 722         strbuf_reset(&buf);
 723
 724         if (ignore_untracked)
 725                 argv[2] = "-uno";
 726
 727         memset(&cp, 0, sizeof(cp));
 728         cp.argv = argv;
 729         cp.env = local_repo_env;
 730         cp.git_cmd = 1;
 731         cp.no_stdin = 1;
 732         cp.out = -1;
 733         cp.dir = path;
 734         if (start_command(&cp))
 735                 die("Could not run 'git status --porcelain' in submodule %s", path);
 736
 737         len = strbuf_read(&buf, cp.out, 1024);
 738         line = buf.buf;
 739         while (len > 2) {
 740                 if ((line[0] == '?') && (line[1] == '?')) {
 741                         dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
 742                         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
 743                                 break;
 744                 } else {
 745                         dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
 746                         if (ignore_untracked ||
 747                             (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED))
 748                                 break;
 749                 }
 750                 next_line = strchr(line, '\n');
 751                 if (!next_line)
 752                         break;
 753                 next_line++;
 754                 len -= (next_line - line);
 755                 line = next_line;
 756         }
 757         close(cp.out);
 758
 759         if (finish_command(&cp))
 760                 die("'git status --porcelain' failed in submodule %s", path);
 761
 762         strbuf_release(&buf);
 763         return dirty_submodule;
 764 }
 765
 766 int submodule_uses_gitfile(const char *path)
 767 {
 768         struct child_process cp;
 769         const char *argv[] = {
 770                 "submodule",
 771                 "foreach",
 772                 "--quiet",
 773                 "--recursive",
 774                 "test -f .git",
 775                 NULL,
 776         };
 777         struct strbuf buf = STRBUF_INIT;
 778         const char *git_dir;
 779
 780         strbuf_addf(&buf, "%s/.git", path);
 781         git_dir = read_gitfile(buf.buf);
 782         if (!git_dir) {
 783                 strbuf_release(&buf);
 784                 return 0;
 785         }
 786         strbuf_release(&buf);
 787
 788         /* Now test that all nested submodules use a gitfile too */
 789         memset(&cp, 0, sizeof(cp));
 790         cp.argv = argv;
 791         cp.env = local_repo_env;
 792         cp.git_cmd = 1;
 793         cp.no_stdin = 1;
 794         cp.no_stderr = 1;
 795         cp.no_stdout = 1;
 796         cp.dir = path;
 797         if (run_command(&cp))
 798                 return 0;
 799
 800         return 1;
 801 }
 802
 803 int ok_to_remove_submodule(const char *path)
 804 {
 805         struct stat st;
 806         ssize_t len;
 807         struct child_process cp;
 808         const char *argv[] = {
 809                 "status",
 810                 "--porcelain",
 811                 "-u",
 812                 "--ignore-submodules=none",
 813                 NULL,
 814         };
 815         struct strbuf buf = STRBUF_INIT;
 816         int ok_to_remove = 1;
 817
 818         if ((lstat(path, &st) < 0) || is_empty_dir(path))
 819                 return 1;
 820
 821         if (!submodule_uses_gitfile(path))
 822                 return 0;
 823
 824         memset(&cp, 0, sizeof(cp));
 825         cp.argv = argv;
 826         cp.env = local_repo_env;
 827         cp.git_cmd = 1;
 828         cp.no_stdin = 1;
 829         cp.out = -1;
 830         cp.dir = path;
 831         if (start_command(&cp))
 832                 die("Could not run 'git status --porcelain -uall --ignore-submodules=none' in submodule %s", path);
 833
 834         len = strbuf_read(&buf, cp.out, 1024);
 835         if (len > 2)
 836                 ok_to_remove = 0;
 837         close(cp.out);
 838
 839         if (finish_command(&cp))
 840                 die("'git status --porcelain -uall --ignore-submodules=none' failed in submodule %s", path);
 841
 842         strbuf_release(&buf);
 843         return ok_to_remove;
 844 }
 845
 846 static int find_first_merges(struct object_array *result, const char *path,
 847                 struct commit *a, struct commit *b)
 848 {
 849         int i, j;
 850         struct object_array merges;
 851         struct commit *commit;
 852         int contains_another;
 853
 854         char merged_revision[42];
 855         const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
 856                                    "--all", merged_revision, NULL };
 857         struct rev_info revs;
 858         struct setup_revision_opt rev_opts;
 859
 860         memset(&merges, 0, sizeof(merges));
 861         memset(result, 0, sizeof(struct object_array));
 862         memset(&rev_opts, 0, sizeof(rev_opts));
 863
 864         /* get all revisions that merge commit a */
 865         snprintf(merged_revision, sizeof(merged_revision), "^%s",
 866                         sha1_to_hex(a->object.sha1));
 867         init_revisions(&revs, NULL);
 868         rev_opts.submodule = path;
 869         setup_revisions(sizeof(rev_args)/sizeof(char *)-1, rev_args, &revs, &rev_opts);
 870
 871         /* save all revisions from the above list that contain b */
 872         if (prepare_revision_walk(&revs))
 873                 die("revision walk setup failed");
 874         while ((commit = get_revision(&revs)) != NULL) {
 875                 struct object *o = &(commit->object);
 876                 if (in_merge_bases(b, commit))
 877                         add_object_array(o, NULL, &merges);
 878         }
 879         reset_revision_walk();
 880
 881         /* Now we've got all merges that contain a and b. Prune all
 882          * merges that contain another found merge and save them in
 883          * result.
 884          */
 885         for (i = 0; i < merges.nr; i++) {
 886                 struct commit *m1 = (struct commit *) merges.objects[i].item;
 887
 888                 contains_another = 0;
 889                 for (j = 0; j < merges.nr; j++) {
 890                         struct commit *m2 = (struct commit *) merges.objects[j].item;
 891                         if (i != j && in_merge_bases(m2, m1)) {
 892                                 contains_another = 1;
 893                                 break;
 894                         }
 895                 }
 896
 897                 if (!contains_another)
 898                         add_object_array(merges.objects[i].item,
 899                                          merges.objects[i].name, result);
 900         }
 901
 902         free(merges.objects);
 903         return result->nr;
 904 }
 905
 906 static void print_commit(struct commit *commit)
 907 {
 908         struct strbuf sb = STRBUF_INIT;
 909         struct pretty_print_context ctx = {0};
 910         ctx.date_mode = DATE_NORMAL;
 911         format_commit_message(commit, " %h: %m %s", &sb, &ctx);
 912         fprintf(stderr, "%s\n", sb.buf);
 913         strbuf_release(&sb);
 914 }
 915
 916 #define MERGE_WARNING(path, msg) \
 917         warning("Failed to merge submodule %s (%s)", path, msg);
 918
 919 int merge_submodule(unsigned char result[20], const char *path,
 920                     const unsigned char base[20], const unsigned char a[20],
 921                     const unsigned char b[20], int search)
 922 {
 923         struct commit *commit_base, *commit_a, *commit_b;
 924         int parent_count;
 925         struct object_array merges;
 926
 927         int i;
 928
 929         /* store a in result in case we fail */
 930         hashcpy(result, a);
 931
 932         /* we can not handle deletion conflicts */
 933         if (is_null_sha1(base))
 934                 return 0;
 935         if (is_null_sha1(a))
 936                 return 0;
 937         if (is_null_sha1(b))
 938                 return 0;
 939
 940         if (add_submodule_odb(path)) {
 941                 MERGE_WARNING(path, "not checked out");
 942                 return 0;
 943         }
 944
 945         if (!(commit_base = lookup_commit_reference(base)) ||
 946             !(commit_a = lookup_commit_reference(a)) ||
 947             !(commit_b = lookup_commit_reference(b))) {
 948                 MERGE_WARNING(path, "commits not present");
 949                 return 0;
 950         }
 951
 952         /* check whether both changes are forward */
 953         if (!in_merge_bases(commit_base, commit_a) ||
 954             !in_merge_bases(commit_base, commit_b)) {
 955                 MERGE_WARNING(path, "commits don't follow merge-base");
 956                 return 0;
 957         }
 958
 959         /* Case #1: a is contained in b or vice versa */
 960         if (in_merge_bases(commit_a, commit_b)) {
 961                 hashcpy(result, b);
 962                 return 1;
 963         }
 964         if (in_merge_bases(commit_b, commit_a)) {
 965                 hashcpy(result, a);
 966                 return 1;
 967         }
 968
 969         /*
 970          * Case #2: There are one or more merges that contain a and b in
 971          * the submodule. If there is only one, then present it as a
 972          * suggestion to the user, but leave it marked unmerged so the
 973          * user needs to confirm the resolution.
 974          */
 975
 976         /* Skip the search if makes no sense to the calling context.  */
 977         if (!search)
 978                 return 0;
 979
 980         /* find commit which merges them */
 981         parent_count = find_first_merges(&merges, path, commit_a, commit_b);
 982         switch (parent_count) {
 983         case 0:
 984                 MERGE_WARNING(path, "merge following commits not found");
 985                 break;
 986
 987         case 1:
 988                 MERGE_WARNING(path, "not fast-forward");
 989                 fprintf(stderr, "Found a possible merge resolution "
 990                                 "for the submodule:\n");
 991                 print_commit((struct commit *) merges.objects[0].item);
 992                 fprintf(stderr,
 993                         "If this is correct simply add it to the index "
 994                         "for example\n"
 995                         "by using:\n\n"
 996                         "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
 997                         "which will accept this suggestion.\n",
 998                         sha1_to_hex(merges.objects[0].item->sha1), path);
 999                 break;
1000
1001         default:
1002                 MERGE_WARNING(path, "multiple merges found");
1003                 for (i = 0; i < merges.nr; i++)
1004                         print_commit((struct commit *) merges.objects[i].item);
1005         }
1006
1007         free(merges.objects);
1008         return 0;
1009 }