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 #include "blob.h"
  14
  15 static struct string_list config_name_for_path;
  16 static struct string_list config_fetch_recurse_submodules_for_name;
  17 static struct string_list config_ignore_for_name;
  18 static int config_fetch_recurse_submodules = RECURSE_SUBMODULES_ON_DEMAND;
  19 static struct string_list changed_submodule_paths;
  20 static int initialized_fetch_ref_tips;
  21 static struct sha1_array ref_tips_before_fetch;
  22 static struct sha1_array ref_tips_after_fetch;
  23
  24 /*
  25  * The following flag is set if the .gitmodules file is unmerged. We then
  26  * disable recursion for all submodules where .git/config doesn't have a
  27  * matching config entry because we can't guess what might be configured in
  28  * .gitmodules unless the user resolves the conflict. When a command line
  29  * option is given (which always overrides configuration) this flag will be
  30  * ignored.
  31  */
  32 static int gitmodules_is_unmerged;
  33
  34 /*
  35  * This flag is set if the .gitmodules file had unstaged modifications on
  36  * startup. This must be checked before allowing modifications to the
  37  * .gitmodules file with the intention to stage them later, because when
  38  * continuing we would stage the modifications the user didn't stage herself
  39  * too. That might change in a future version when we learn to stage the
  40  * changes we do ourselves without staging any previous modifications.
  41  */
  42 static int gitmodules_is_modified;
  43
  44
  45 int is_staging_gitmodules_ok(void)
  46 {
  47         return !gitmodules_is_modified;
  48 }
  49
  50 /*
  51  * Try to update the "path" entry in the "submodule.<name>" section of the
  52  * .gitmodules file. Return 0 only if a .gitmodules file was found, a section
  53  * with the correct path=<oldpath> setting was found and we could update it.
  54  */
  55 int update_path_in_gitmodules(const char *oldpath, const char *newpath)
  56 {
  57         struct strbuf entry = STRBUF_INIT;
  58         struct string_list_item *path_option;
  59
  60         if (!file_exists(".gitmodules")) /* Do nothing without .gitmodules */
  61                 return -1;
  62
  63         if (gitmodules_is_unmerged)
  64                 die(_("Cannot change unmerged .gitmodules, resolve merge conflicts first"));
  65
  66         path_option = unsorted_string_list_lookup(&config_name_for_path, oldpath);
  67         if (!path_option) {
  68                 warning(_("Could not find section in .gitmodules where path=%s"), oldpath);
  69                 return -1;
  70         }
  71         strbuf_addstr(&entry, "submodule.");
  72         strbuf_addstr(&entry, path_option->util);
  73         strbuf_addstr(&entry, ".path");
  74         if (git_config_set_in_file(".gitmodules", entry.buf, newpath) < 0) {
  75                 /* Maybe the user already did that, don't error out here */
  76                 warning(_("Could not update .gitmodules entry %s"), entry.buf);
  77                 strbuf_release(&entry);
  78                 return -1;
  79         }
  80         strbuf_release(&entry);
  81         return 0;
  82 }
  83
  84 void stage_updated_gitmodules(void)
  85 {
  86         struct strbuf buf = STRBUF_INIT;
  87         struct stat st;
  88         int pos;
  89         struct cache_entry *ce;
  90         int namelen = strlen(".gitmodules");
  91
  92         pos = cache_name_pos(".gitmodules", namelen);
  93         if (pos < 0) {
  94                 warning(_("could not find .gitmodules in index"));
  95                 return;
  96         }
  97         ce = active_cache[pos];
  98         ce->ce_flags = namelen;
  99         if (strbuf_read_file(&buf, ".gitmodules", 0) < 0)
 100                 die(_("reading updated .gitmodules failed"));
 101         if (lstat(".gitmodules", &st) < 0)
 102                 die_errno(_("unable to stat updated .gitmodules"));
 103         fill_stat_cache_info(ce, &st);
 104         ce->ce_mode = ce_mode_from_stat(ce, st.st_mode);
 105         if (remove_cache_entry_at(pos) < 0)
 106                 die(_("unable to remove .gitmodules from index"));
 107         if (write_sha1_file(buf.buf, buf.len, blob_type, ce->sha1))
 108                 die(_("adding updated .gitmodules failed"));
 109         if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE))
 110                 die(_("staging updated .gitmodules failed"));
 111 }
 112
 113 static int add_submodule_odb(const char *path)
 114 {
 115         struct strbuf objects_directory = STRBUF_INIT;
 116         struct alternate_object_database *alt_odb;
 117         int ret = 0;
 118         const char *git_dir;
 119
 120         strbuf_addf(&objects_directory, "%s/.git", path);
 121         git_dir = read_gitfile(objects_directory.buf);
 122         if (git_dir) {
 123                 strbuf_reset(&objects_directory);
 124                 strbuf_addstr(&objects_directory, git_dir);
 125         }
 126         strbuf_addstr(&objects_directory, "/objects/");
 127         if (!is_directory(objects_directory.buf)) {
 128                 ret = -1;
 129                 goto done;
 130         }
 131         /* avoid adding it twice */
 132         for (alt_odb = alt_odb_list; alt_odb; alt_odb = alt_odb->next)
 133                 if (alt_odb->name - alt_odb->base == objects_directory.len &&
 134                                 !strncmp(alt_odb->base, objects_directory.buf,
 135                                         objects_directory.len))
 136                         goto done;
 137
 138         alt_odb = xmalloc(objects_directory.len + 42 + sizeof(*alt_odb));
 139         alt_odb->next = alt_odb_list;
 140         strcpy(alt_odb->base, objects_directory.buf);
 141         alt_odb->name = alt_odb->base + objects_directory.len;
 142         alt_odb->name[2] = '/';
 143         alt_odb->name[40] = '\0';
 144         alt_odb->name[41] = '\0';
 145         alt_odb_list = alt_odb;
 146
 147         /* add possible alternates from the submodule */
 148         read_info_alternates(objects_directory.buf, 0);
 149         prepare_alt_odb();
 150 done:
 151         strbuf_release(&objects_directory);
 152         return ret;
 153 }
 154
 155 void set_diffopt_flags_from_submodule_config(struct diff_options *diffopt,
 156                                              const char *path)
 157 {
 158         struct string_list_item *path_option, *ignore_option;
 159         path_option = unsorted_string_list_lookup(&config_name_for_path, path);
 160         if (path_option) {
 161                 ignore_option = unsorted_string_list_lookup(&config_ignore_for_name, path_option->util);
 162                 if (ignore_option)
 163                         handle_ignore_submodules_arg(diffopt, ignore_option->util);
 164                 else if (gitmodules_is_unmerged)
 165                         DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
 166         }
 167 }
 168
 169 int submodule_config(const char *var, const char *value, void *cb)
 170 {
 171         if (!prefixcmp(var, "submodule."))
 172                 return parse_submodule_config_option(var, value);
 173         else if (!strcmp(var, "fetch.recursesubmodules")) {
 174                 config_fetch_recurse_submodules = parse_fetch_recurse_submodules_arg(var, value);
 175                 return 0;
 176         }
 177         return 0;
 178 }
 179
 180 void gitmodules_config(void)
 181 {
 182         const char *work_tree = get_git_work_tree();
 183         if (work_tree) {
 184                 struct strbuf gitmodules_path = STRBUF_INIT;
 185                 int pos;
 186                 strbuf_addstr(&gitmodules_path, work_tree);
 187                 strbuf_addstr(&gitmodules_path, "/.gitmodules");
 188                 if (read_cache() < 0)
 189                         die("index file corrupt");
 190                 pos = cache_name_pos(".gitmodules", 11);
 191                 if (pos < 0) { /* .gitmodules not found or isn't merged */
 192                         pos = -1 - pos;
 193                         if (active_nr > pos) {  /* there is a .gitmodules */
 194                                 const struct cache_entry *ce = active_cache[pos];
 195                                 if (ce_namelen(ce) == 11 &&
 196                                     !memcmp(ce->name, ".gitmodules", 11))
 197                                         gitmodules_is_unmerged = 1;
 198                         }
 199                 } else if (pos < active_nr) {
 200                         struct stat st;
 201                         if (lstat(".gitmodules", &st) == 0 &&
 202                             ce_match_stat(active_cache[pos], &st, 0) & DATA_CHANGED)
 203                                 gitmodules_is_modified = 1;
 204                 }
 205
 206                 if (!gitmodules_is_unmerged)
 207                         git_config_from_file(submodule_config, gitmodules_path.buf, NULL);
 208                 strbuf_release(&gitmodules_path);
 209         }
 210 }
 211
 212 int parse_submodule_config_option(const char *var, const char *value)
 213 {
 214         struct string_list_item *config;
 215         const char *name, *key;
 216         int namelen;
 217
 218         if (parse_config_key(var, "submodule", &name, &namelen, &key) < 0 || !name)
 219                 return 0;
 220
 221         if (!strcmp(key, "path")) {
 222                 config = unsorted_string_list_lookup(&config_name_for_path, value);
 223                 if (config)
 224                         free(config->util);
 225                 else
 226                         config = string_list_append(&config_name_for_path, xstrdup(value));
 227                 config->util = xmemdupz(name, namelen);
 228         } else if (!strcmp(key, "fetchrecursesubmodules")) {
 229                 char *name_cstr = xmemdupz(name, namelen);
 230                 config = unsorted_string_list_lookup(&config_fetch_recurse_submodules_for_name, name_cstr);
 231                 if (!config)
 232                         config = string_list_append(&config_fetch_recurse_submodules_for_name, name_cstr);
 233                 else
 234                         free(name_cstr);
 235                 config->util = (void *)(intptr_t)parse_fetch_recurse_submodules_arg(var, value);
 236         } else if (!strcmp(key, "ignore")) {
 237                 char *name_cstr;
 238
 239                 if (strcmp(value, "untracked") && strcmp(value, "dirty") &&
 240                     strcmp(value, "all") && strcmp(value, "none")) {
 241                         warning("Invalid parameter \"%s\" for config option \"submodule.%s.ignore\"", value, var);
 242                         return 0;
 243                 }
 244
 245                 name_cstr = xmemdupz(name, namelen);
 246                 config = unsorted_string_list_lookup(&config_ignore_for_name, name_cstr);
 247                 if (config) {
 248                         free(config->util);
 249                         free(name_cstr);
 250                 } else
 251                         config = string_list_append(&config_ignore_for_name, name_cstr);
 252                 config->util = xstrdup(value);
 253                 return 0;
 254         }
 255         return 0;
 256 }
 257
 258 void handle_ignore_submodules_arg(struct diff_options *diffopt,
 259                                   const char *arg)
 260 {
 261         DIFF_OPT_CLR(diffopt, IGNORE_SUBMODULES);
 262         DIFF_OPT_CLR(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 263         DIFF_OPT_CLR(diffopt, IGNORE_DIRTY_SUBMODULES);
 264
 265         if (!strcmp(arg, "all"))
 266                 DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
 267         else if (!strcmp(arg, "untracked"))
 268                 DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 269         else if (!strcmp(arg, "dirty"))
 270                 DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES);
 271         else if (strcmp(arg, "none"))
 272                 die("bad --ignore-submodules argument: %s", arg);
 273 }
 274
 275 static int prepare_submodule_summary(struct rev_info *rev, const char *path,
 276                 struct commit *left, struct commit *right,
 277                 int *fast_forward, int *fast_backward)
 278 {
 279         struct commit_list *merge_bases, *list;
 280
 281         init_revisions(rev, NULL);
 282         setup_revisions(0, NULL, rev, NULL);
 283         rev->left_right = 1;
 284         rev->first_parent_only = 1;
 285         left->object.flags |= SYMMETRIC_LEFT;
 286         add_pending_object(rev, &left->object, path);
 287         add_pending_object(rev, &right->object, path);
 288         merge_bases = get_merge_bases(left, right, 1);
 289         if (merge_bases) {
 290                 if (merge_bases->item == left)
 291                         *fast_forward = 1;
 292                 else if (merge_bases->item == right)
 293                         *fast_backward = 1;
 294         }
 295         for (list = merge_bases; list; list = list->next) {
 296                 list->item->object.flags |= UNINTERESTING;
 297                 add_pending_object(rev, &list->item->object,
 298                         sha1_to_hex(list->item->object.sha1));
 299         }
 300         return prepare_revision_walk(rev);
 301 }
 302
 303 static void print_submodule_summary(struct rev_info *rev, FILE *f,
 304                 const char *line_prefix,
 305                 const char *del, const char *add, const char *reset)
 306 {
 307         static const char format[] = "  %m %s";
 308         struct strbuf sb = STRBUF_INIT;
 309         struct commit *commit;
 310
 311         while ((commit = get_revision(rev))) {
 312                 struct pretty_print_context ctx = {0};
 313                 ctx.date_mode = rev->date_mode;
 314                 ctx.output_encoding = get_log_output_encoding();
 315                 strbuf_setlen(&sb, 0);
 316                 strbuf_addstr(&sb, line_prefix);
 317                 if (commit->object.flags & SYMMETRIC_LEFT) {
 318                         if (del)
 319                                 strbuf_addstr(&sb, del);
 320                 }
 321                 else if (add)
 322                         strbuf_addstr(&sb, add);
 323                 format_commit_message(commit, format, &sb, &ctx);
 324                 if (reset)
 325                         strbuf_addstr(&sb, reset);
 326                 strbuf_addch(&sb, '\n');
 327                 fprintf(f, "%s", sb.buf);
 328         }
 329         strbuf_release(&sb);
 330 }
 331
 332 int parse_fetch_recurse_submodules_arg(const char *opt, const char *arg)
 333 {
 334         switch (git_config_maybe_bool(opt, arg)) {
 335         case 1:
 336                 return RECURSE_SUBMODULES_ON;
 337         case 0:
 338                 return RECURSE_SUBMODULES_OFF;
 339         default:
 340                 if (!strcmp(arg, "on-demand"))
 341                         return RECURSE_SUBMODULES_ON_DEMAND;
 342                 die("bad %s argument: %s", opt, arg);
 343         }
 344 }
 345
 346 void show_submodule_summary(FILE *f, const char *path,
 347                 const char *line_prefix,
 348                 unsigned char one[20], unsigned char two[20],
 349                 unsigned dirty_submodule, const char *meta,
 350                 const char *del, const char *add, const char *reset)
 351 {
 352         struct rev_info rev;
 353         struct commit *left = NULL, *right = NULL;
 354         const char *message = NULL;
 355         struct strbuf sb = STRBUF_INIT;
 356         int fast_forward = 0, fast_backward = 0;
 357
 358         if (is_null_sha1(two))
 359                 message = "(submodule deleted)";
 360         else if (add_submodule_odb(path))
 361                 message = "(not checked out)";
 362         else if (is_null_sha1(one))
 363                 message = "(new submodule)";
 364         else if (!(left = lookup_commit_reference(one)) ||
 365                  !(right = lookup_commit_reference(two)))
 366                 message = "(commits not present)";
 367         else if (prepare_submodule_summary(&rev, path, left, right,
 368                                            &fast_forward, &fast_backward))
 369                 message = "(revision walker failed)";
 370
 371         if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
 372                 fprintf(f, "%sSubmodule %s contains untracked content\n",
 373                         line_prefix, path);
 374         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
 375                 fprintf(f, "%sSubmodule %s contains modified content\n",
 376                         line_prefix, path);
 377
 378         if (!hashcmp(one, two)) {
 379                 strbuf_release(&sb);
 380                 return;
 381         }
 382
 383         strbuf_addf(&sb, "%s%sSubmodule %s %s..", line_prefix, meta, path,
 384                         find_unique_abbrev(one, DEFAULT_ABBREV));
 385         if (!fast_backward && !fast_forward)
 386                 strbuf_addch(&sb, '.');
 387         strbuf_addf(&sb, "%s", find_unique_abbrev(two, DEFAULT_ABBREV));
 388         if (message)
 389                 strbuf_addf(&sb, " %s%s\n", message, reset);
 390         else
 391                 strbuf_addf(&sb, "%s:%s\n", fast_backward ? " (rewind)" : "", reset);
 392         fwrite(sb.buf, sb.len, 1, f);
 393
 394         if (!message) /* only NULL if we succeeded in setting up the walk */
 395                 print_submodule_summary(&rev, f, line_prefix, del, add, reset);
 396         if (left)
 397                 clear_commit_marks(left, ~0);
 398         if (right)
 399                 clear_commit_marks(right, ~0);
 400
 401         strbuf_release(&sb);
 402 }
 403
 404 void set_config_fetch_recurse_submodules(int value)
 405 {
 406         config_fetch_recurse_submodules = value;
 407 }
 408
 409 static int has_remote(const char *refname, const unsigned char *sha1, int flags, void *cb_data)
 410 {
 411         return 1;
 412 }
 413
 414 static int submodule_needs_pushing(const char *path, const unsigned char sha1[20])
 415 {
 416         if (add_submodule_odb(path) || !lookup_commit_reference(sha1))
 417                 return 0;
 418
 419         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 420                 struct child_process cp;
 421                 const char *argv[] = {"rev-list", NULL, "--not", "--remotes", "-n", "1" , NULL};
 422                 struct strbuf buf = STRBUF_INIT;
 423                 int needs_pushing = 0;
 424
 425                 argv[1] = sha1_to_hex(sha1);
 426                 memset(&cp, 0, sizeof(cp));
 427                 cp.argv = argv;
 428                 cp.env = local_repo_env;
 429                 cp.git_cmd = 1;
 430                 cp.no_stdin = 1;
 431                 cp.out = -1;
 432                 cp.dir = path;
 433                 if (start_command(&cp))
 434                         die("Could not run 'git rev-list %s --not --remotes -n 1' command in submodule %s",
 435                                 sha1_to_hex(sha1), path);
 436                 if (strbuf_read(&buf, cp.out, 41))
 437                         needs_pushing = 1;
 438                 finish_command(&cp);
 439                 close(cp.out);
 440                 strbuf_release(&buf);
 441                 return needs_pushing;
 442         }
 443
 444         return 0;
 445 }
 446
 447 static void collect_submodules_from_diff(struct diff_queue_struct *q,
 448                                          struct diff_options *options,
 449                                          void *data)
 450 {
 451         int i;
 452         struct string_list *needs_pushing = data;
 453
 454         for (i = 0; i < q->nr; i++) {
 455                 struct diff_filepair *p = q->queue[i];
 456                 if (!S_ISGITLINK(p->two->mode))
 457                         continue;
 458                 if (submodule_needs_pushing(p->two->path, p->two->sha1))
 459                         string_list_insert(needs_pushing, p->two->path);
 460         }
 461 }
 462
 463 static void find_unpushed_submodule_commits(struct commit *commit,
 464                 struct string_list *needs_pushing)
 465 {
 466         struct rev_info rev;
 467
 468         init_revisions(&rev, NULL);
 469         rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
 470         rev.diffopt.format_callback = collect_submodules_from_diff;
 471         rev.diffopt.format_callback_data = needs_pushing;
 472         diff_tree_combined_merge(commit, 1, &rev);
 473 }
 474
 475 int find_unpushed_submodules(unsigned char new_sha1[20],
 476                 const char *remotes_name, struct string_list *needs_pushing)
 477 {
 478         struct rev_info rev;
 479         struct commit *commit;
 480         const char *argv[] = {NULL, NULL, "--not", "NULL", NULL};
 481         int argc = ARRAY_SIZE(argv) - 1;
 482         char *sha1_copy;
 483
 484         struct strbuf remotes_arg = STRBUF_INIT;
 485
 486         strbuf_addf(&remotes_arg, "--remotes=%s", remotes_name);
 487         init_revisions(&rev, NULL);
 488         sha1_copy = xstrdup(sha1_to_hex(new_sha1));
 489         argv[1] = sha1_copy;
 490         argv[3] = remotes_arg.buf;
 491         setup_revisions(argc, argv, &rev, NULL);
 492         if (prepare_revision_walk(&rev))
 493                 die("revision walk setup failed");
 494
 495         while ((commit = get_revision(&rev)) != NULL)
 496                 find_unpushed_submodule_commits(commit, needs_pushing);
 497
 498         reset_revision_walk();
 499         free(sha1_copy);
 500         strbuf_release(&remotes_arg);
 501
 502         return needs_pushing->nr;
 503 }
 504
 505 static int push_submodule(const char *path)
 506 {
 507         if (add_submodule_odb(path))
 508                 return 1;
 509
 510         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 511                 struct child_process cp;
 512                 const char *argv[] = {"push", NULL};
 513
 514                 memset(&cp, 0, sizeof(cp));
 515                 cp.argv = argv;
 516                 cp.env = local_repo_env;
 517                 cp.git_cmd = 1;
 518                 cp.no_stdin = 1;
 519                 cp.dir = path;
 520                 if (run_command(&cp))
 521                         return 0;
 522                 close(cp.out);
 523         }
 524
 525         return 1;
 526 }
 527
 528 int push_unpushed_submodules(unsigned char new_sha1[20], const char *remotes_name)
 529 {
 530         int i, ret = 1;
 531         struct string_list needs_pushing;
 532
 533         memset(&needs_pushing, 0, sizeof(struct string_list));
 534         needs_pushing.strdup_strings = 1;
 535
 536         if (!find_unpushed_submodules(new_sha1, remotes_name, &needs_pushing))
 537                 return 1;
 538
 539         for (i = 0; i < needs_pushing.nr; i++) {
 540                 const char *path = needs_pushing.items[i].string;
 541                 fprintf(stderr, "Pushing submodule '%s'\n", path);
 542                 if (!push_submodule(path)) {
 543                         fprintf(stderr, "Unable to push submodule '%s'\n", path);
 544                         ret = 0;
 545                 }
 546         }
 547
 548         string_list_clear(&needs_pushing, 0);
 549
 550         return ret;
 551 }
 552
 553 static int is_submodule_commit_present(const char *path, unsigned char sha1[20])
 554 {
 555         int is_present = 0;
 556         if (!add_submodule_odb(path) && lookup_commit_reference(sha1)) {
 557                 /* Even if the submodule is checked out and the commit is
 558                  * present, make sure it is reachable from a ref. */
 559                 struct child_process cp;
 560                 const char *argv[] = {"rev-list", "-n", "1", NULL, "--not", "--all", NULL};
 561                 struct strbuf buf = STRBUF_INIT;
 562
 563                 argv[3] = sha1_to_hex(sha1);
 564                 memset(&cp, 0, sizeof(cp));
 565                 cp.argv = argv;
 566                 cp.env = local_repo_env;
 567                 cp.git_cmd = 1;
 568                 cp.no_stdin = 1;
 569                 cp.out = -1;
 570                 cp.dir = path;
 571                 if (!run_command(&cp) && !strbuf_read(&buf, cp.out, 1024))
 572                         is_present = 1;
 573
 574                 close(cp.out);
 575                 strbuf_release(&buf);
 576         }
 577         return is_present;
 578 }
 579
 580 static void submodule_collect_changed_cb(struct diff_queue_struct *q,
 581                                          struct diff_options *options,
 582                                          void *data)
 583 {
 584         int i;
 585         for (i = 0; i < q->nr; i++) {
 586                 struct diff_filepair *p = q->queue[i];
 587                 if (!S_ISGITLINK(p->two->mode))
 588                         continue;
 589
 590                 if (S_ISGITLINK(p->one->mode)) {
 591                         /* NEEDSWORK: We should honor the name configured in
 592                          * the .gitmodules file of the commit we are examining
 593                          * here to be able to correctly follow submodules
 594                          * being moved around. */
 595                         struct string_list_item *path;
 596                         path = unsorted_string_list_lookup(&changed_submodule_paths, p->two->path);
 597                         if (!path && !is_submodule_commit_present(p->two->path, p->two->sha1))
 598                                 string_list_append(&changed_submodule_paths, xstrdup(p->two->path));
 599                 } else {
 600                         /* Submodule is new or was moved here */
 601                         /* NEEDSWORK: When the .git directories of submodules
 602                          * live inside the superprojects .git directory some
 603                          * day we should fetch new submodules directly into
 604                          * that location too when config or options request
 605                          * that so they can be checked out from there. */
 606                         continue;
 607                 }
 608         }
 609 }
 610
 611 static int add_sha1_to_array(const char *ref, const unsigned char *sha1,
 612                              int flags, void *data)
 613 {
 614         sha1_array_append(data, sha1);
 615         return 0;
 616 }
 617
 618 void check_for_new_submodule_commits(unsigned char new_sha1[20])
 619 {
 620         if (!initialized_fetch_ref_tips) {
 621                 for_each_ref(add_sha1_to_array, &ref_tips_before_fetch);
 622                 initialized_fetch_ref_tips = 1;
 623         }
 624
 625         sha1_array_append(&ref_tips_after_fetch, new_sha1);
 626 }
 627
 628 static void add_sha1_to_argv(const unsigned char sha1[20], void *data)
 629 {
 630         argv_array_push(data, sha1_to_hex(sha1));
 631 }
 632
 633 static void calculate_changed_submodule_paths(void)
 634 {
 635         struct rev_info rev;
 636         struct commit *commit;
 637         struct argv_array argv = ARGV_ARRAY_INIT;
 638
 639         /* No need to check if there are no submodules configured */
 640         if (!config_name_for_path.nr)
 641                 return;
 642
 643         init_revisions(&rev, NULL);
 644         argv_array_push(&argv, "--"); /* argv[0] program name */
 645         sha1_array_for_each_unique(&ref_tips_after_fetch,
 646                                    add_sha1_to_argv, &argv);
 647         argv_array_push(&argv, "--not");
 648         sha1_array_for_each_unique(&ref_tips_before_fetch,
 649                                    add_sha1_to_argv, &argv);
 650         setup_revisions(argv.argc, argv.argv, &rev, NULL);
 651         if (prepare_revision_walk(&rev))
 652                 die("revision walk setup failed");
 653
 654         /*
 655          * Collect all submodules (whether checked out or not) for which new
 656          * commits have been recorded upstream in "changed_submodule_paths".
 657          */
 658         while ((commit = get_revision(&rev))) {
 659                 struct commit_list *parent = commit->parents;
 660                 while (parent) {
 661                         struct diff_options diff_opts;
 662                         diff_setup(&diff_opts);
 663                         DIFF_OPT_SET(&diff_opts, RECURSIVE);
 664                         diff_opts.output_format |= DIFF_FORMAT_CALLBACK;
 665                         diff_opts.format_callback = submodule_collect_changed_cb;
 666                         diff_setup_done(&diff_opts);
 667                         diff_tree_sha1(parent->item->object.sha1, commit->object.sha1, "", &diff_opts);
 668                         diffcore_std(&diff_opts);
 669                         diff_flush(&diff_opts);
 670                         parent = parent->next;
 671                 }
 672         }
 673
 674         argv_array_clear(&argv);
 675         sha1_array_clear(&ref_tips_before_fetch);
 676         sha1_array_clear(&ref_tips_after_fetch);
 677         initialized_fetch_ref_tips = 0;
 678 }
 679
 680 int fetch_populated_submodules(const struct argv_array *options,
 681                                const char *prefix, int command_line_option,
 682                                int quiet)
 683 {
 684         int i, result = 0;
 685         struct child_process cp;
 686         struct argv_array argv = ARGV_ARRAY_INIT;
 687         struct string_list_item *name_for_path;
 688         const char *work_tree = get_git_work_tree();
 689         if (!work_tree)
 690                 goto out;
 691
 692         if (read_cache() < 0)
 693                 die("index file corrupt");
 694
 695         argv_array_push(&argv, "fetch");
 696         for (i = 0; i < options->argc; i++)
 697                 argv_array_push(&argv, options->argv[i]);
 698         argv_array_push(&argv, "--recurse-submodules-default");
 699         /* default value, "--submodule-prefix" and its value are added later */
 700
 701         memset(&cp, 0, sizeof(cp));
 702         cp.env = local_repo_env;
 703         cp.git_cmd = 1;
 704         cp.no_stdin = 1;
 705
 706         calculate_changed_submodule_paths();
 707
 708         for (i = 0; i < active_nr; i++) {
 709                 struct strbuf submodule_path = STRBUF_INIT;
 710                 struct strbuf submodule_git_dir = STRBUF_INIT;
 711                 struct strbuf submodule_prefix = STRBUF_INIT;
 712                 struct cache_entry *ce = active_cache[i];
 713                 const char *git_dir, *name, *default_argv;
 714
 715                 if (!S_ISGITLINK(ce->ce_mode))
 716                         continue;
 717
 718                 name = ce->name;
 719                 name_for_path = unsorted_string_list_lookup(&config_name_for_path, ce->name);
 720                 if (name_for_path)
 721                         name = name_for_path->util;
 722
 723                 default_argv = "yes";
 724                 if (command_line_option == RECURSE_SUBMODULES_DEFAULT) {
 725                         struct string_list_item *fetch_recurse_submodules_option;
 726                         fetch_recurse_submodules_option = unsorted_string_list_lookup(&config_fetch_recurse_submodules_for_name, name);
 727                         if (fetch_recurse_submodules_option) {
 728                                 if ((intptr_t)fetch_recurse_submodules_option->util == RECURSE_SUBMODULES_OFF)
 729                                         continue;
 730                                 if ((intptr_t)fetch_recurse_submodules_option->util == RECURSE_SUBMODULES_ON_DEMAND) {
 731                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 732                                                 continue;
 733                                         default_argv = "on-demand";
 734                                 }
 735                         } else {
 736                                 if ((config_fetch_recurse_submodules == RECURSE_SUBMODULES_OFF) ||
 737                                     gitmodules_is_unmerged)
 738                                         continue;
 739                                 if (config_fetch_recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) {
 740                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 741                                                 continue;
 742                                         default_argv = "on-demand";
 743                                 }
 744                         }
 745                 } else if (command_line_option == RECURSE_SUBMODULES_ON_DEMAND) {
 746                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 747                                 continue;
 748                         default_argv = "on-demand";
 749                 }
 750
 751                 strbuf_addf(&submodule_path, "%s/%s", work_tree, ce->name);
 752                 strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
 753                 strbuf_addf(&submodule_prefix, "%s%s/", prefix, ce->name);
 754                 git_dir = read_gitfile(submodule_git_dir.buf);
 755                 if (!git_dir)
 756                         git_dir = submodule_git_dir.buf;
 757                 if (is_directory(git_dir)) {
 758                         if (!quiet)
 759                                 printf("Fetching submodule %s%s\n", prefix, ce->name);
 760                         cp.dir = submodule_path.buf;
 761                         argv_array_push(&argv, default_argv);
 762                         argv_array_push(&argv, "--submodule-prefix");
 763                         argv_array_push(&argv, submodule_prefix.buf);
 764                         cp.argv = argv.argv;
 765                         if (run_command(&cp))
 766                                 result = 1;
 767                         argv_array_pop(&argv);
 768                         argv_array_pop(&argv);
 769                         argv_array_pop(&argv);
 770                 }
 771                 strbuf_release(&submodule_path);
 772                 strbuf_release(&submodule_git_dir);
 773                 strbuf_release(&submodule_prefix);
 774         }
 775         argv_array_clear(&argv);
 776 out:
 777         string_list_clear(&changed_submodule_paths, 1);
 778         return result;
 779 }
 780
 781 unsigned is_submodule_modified(const char *path, int ignore_untracked)
 782 {
 783         ssize_t len;
 784         struct child_process cp;
 785         const char *argv[] = {
 786                 "status",
 787                 "--porcelain",
 788                 NULL,
 789                 NULL,
 790         };
 791         struct strbuf buf = STRBUF_INIT;
 792         unsigned dirty_submodule = 0;
 793         const char *line, *next_line;
 794         const char *git_dir;
 795
 796         strbuf_addf(&buf, "%s/.git", path);
 797         git_dir = read_gitfile(buf.buf);
 798         if (!git_dir)
 799                 git_dir = buf.buf;
 800         if (!is_directory(git_dir)) {
 801                 strbuf_release(&buf);
 802                 /* The submodule is not checked out, so it is not modified */
 803                 return 0;
 804
 805         }
 806         strbuf_reset(&buf);
 807
 808         if (ignore_untracked)
 809                 argv[2] = "-uno";
 810
 811         memset(&cp, 0, sizeof(cp));
 812         cp.argv = argv;
 813         cp.env = local_repo_env;
 814         cp.git_cmd = 1;
 815         cp.no_stdin = 1;
 816         cp.out = -1;
 817         cp.dir = path;
 818         if (start_command(&cp))
 819                 die("Could not run 'git status --porcelain' in submodule %s", path);
 820
 821         len = strbuf_read(&buf, cp.out, 1024);
 822         line = buf.buf;
 823         while (len > 2) {
 824                 if ((line[0] == '?') && (line[1] == '?')) {
 825                         dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
 826                         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
 827                                 break;
 828                 } else {
 829                         dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
 830                         if (ignore_untracked ||
 831                             (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED))
 832                                 break;
 833                 }
 834                 next_line = strchr(line, '\n');
 835                 if (!next_line)
 836                         break;
 837                 next_line++;
 838                 len -= (next_line - line);
 839                 line = next_line;
 840         }
 841         close(cp.out);
 842
 843         if (finish_command(&cp))
 844                 die("'git status --porcelain' failed in submodule %s", path);
 845
 846         strbuf_release(&buf);
 847         return dirty_submodule;
 848 }
 849
 850 int submodule_uses_gitfile(const char *path)
 851 {
 852         struct child_process cp;
 853         const char *argv[] = {
 854                 "submodule",
 855                 "foreach",
 856                 "--quiet",
 857                 "--recursive",
 858                 "test -f .git",
 859                 NULL,
 860         };
 861         struct strbuf buf = STRBUF_INIT;
 862         const char *git_dir;
 863
 864         strbuf_addf(&buf, "%s/.git", path);
 865         git_dir = read_gitfile(buf.buf);
 866         if (!git_dir) {
 867                 strbuf_release(&buf);
 868                 return 0;
 869         }
 870         strbuf_release(&buf);
 871
 872         /* Now test that all nested submodules use a gitfile too */
 873         memset(&cp, 0, sizeof(cp));
 874         cp.argv = argv;
 875         cp.env = local_repo_env;
 876         cp.git_cmd = 1;
 877         cp.no_stdin = 1;
 878         cp.no_stderr = 1;
 879         cp.no_stdout = 1;
 880         cp.dir = path;
 881         if (run_command(&cp))
 882                 return 0;
 883
 884         return 1;
 885 }
 886
 887 int ok_to_remove_submodule(const char *path)
 888 {
 889         struct stat st;
 890         ssize_t len;
 891         struct child_process cp;
 892         const char *argv[] = {
 893                 "status",
 894                 "--porcelain",
 895                 "-u",
 896                 "--ignore-submodules=none",
 897                 NULL,
 898         };
 899         struct strbuf buf = STRBUF_INIT;
 900         int ok_to_remove = 1;
 901
 902         if ((lstat(path, &st) < 0) || is_empty_dir(path))
 903                 return 1;
 904
 905         if (!submodule_uses_gitfile(path))
 906                 return 0;
 907
 908         memset(&cp, 0, sizeof(cp));
 909         cp.argv = argv;
 910         cp.env = local_repo_env;
 911         cp.git_cmd = 1;
 912         cp.no_stdin = 1;
 913         cp.out = -1;
 914         cp.dir = path;
 915         if (start_command(&cp))
 916                 die("Could not run 'git status --porcelain -uall --ignore-submodules=none' in submodule %s", path);
 917
 918         len = strbuf_read(&buf, cp.out, 1024);
 919         if (len > 2)
 920                 ok_to_remove = 0;
 921         close(cp.out);
 922
 923         if (finish_command(&cp))
 924                 die("'git status --porcelain -uall --ignore-submodules=none' failed in submodule %s", path);
 925
 926         strbuf_release(&buf);
 927         return ok_to_remove;
 928 }
 929
 930 static int find_first_merges(struct object_array *result, const char *path,
 931                 struct commit *a, struct commit *b)
 932 {
 933         int i, j;
 934         struct object_array merges = OBJECT_ARRAY_INIT;
 935         struct commit *commit;
 936         int contains_another;
 937
 938         char merged_revision[42];
 939         const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
 940                                    "--all", merged_revision, NULL };
 941         struct rev_info revs;
 942         struct setup_revision_opt rev_opts;
 943
 944         memset(result, 0, sizeof(struct object_array));
 945         memset(&rev_opts, 0, sizeof(rev_opts));
 946
 947         /* get all revisions that merge commit a */
 948         snprintf(merged_revision, sizeof(merged_revision), "^%s",
 949                         sha1_to_hex(a->object.sha1));
 950         init_revisions(&revs, NULL);
 951         rev_opts.submodule = path;
 952         setup_revisions(sizeof(rev_args)/sizeof(char *)-1, rev_args, &revs, &rev_opts);
 953
 954         /* save all revisions from the above list that contain b */
 955         if (prepare_revision_walk(&revs))
 956                 die("revision walk setup failed");
 957         while ((commit = get_revision(&revs)) != NULL) {
 958                 struct object *o = &(commit->object);
 959                 if (in_merge_bases(b, commit))
 960                         add_object_array(o, NULL, &merges);
 961         }
 962         reset_revision_walk();
 963
 964         /* Now we've got all merges that contain a and b. Prune all
 965          * merges that contain another found merge and save them in
 966          * result.
 967          */
 968         for (i = 0; i < merges.nr; i++) {
 969                 struct commit *m1 = (struct commit *) merges.objects[i].item;
 970
 971                 contains_another = 0;
 972                 for (j = 0; j < merges.nr; j++) {
 973                         struct commit *m2 = (struct commit *) merges.objects[j].item;
 974                         if (i != j && in_merge_bases(m2, m1)) {
 975                                 contains_another = 1;
 976                                 break;
 977                         }
 978                 }
 979
 980                 if (!contains_another)
 981                         add_object_array(merges.objects[i].item, NULL, result);
 982         }
 983
 984         free(merges.objects);
 985         return result->nr;
 986 }
 987
 988 static void print_commit(struct commit *commit)
 989 {
 990         struct strbuf sb = STRBUF_INIT;
 991         struct pretty_print_context ctx = {0};
 992         ctx.date_mode = DATE_NORMAL;
 993         format_commit_message(commit, " %h: %m %s", &sb, &ctx);
 994         fprintf(stderr, "%s\n", sb.buf);
 995         strbuf_release(&sb);
 996 }
 997
 998 #define MERGE_WARNING(path, msg) \
 999         warning("Failed to merge submodule %s (%s)", path, msg);
1000
1001 int merge_submodule(unsigned char result[20], const char *path,
1002                     const unsigned char base[20], const unsigned char a[20],
1003                     const unsigned char b[20], int search)
1004 {
1005         struct commit *commit_base, *commit_a, *commit_b;
1006         int parent_count;
1007         struct object_array merges;
1008
1009         int i;
1010
1011         /* store a in result in case we fail */
1012         hashcpy(result, a);
1013
1014         /* we can not handle deletion conflicts */
1015         if (is_null_sha1(base))
1016                 return 0;
1017         if (is_null_sha1(a))
1018                 return 0;
1019         if (is_null_sha1(b))
1020                 return 0;
1021
1022         if (add_submodule_odb(path)) {
1023                 MERGE_WARNING(path, "not checked out");
1024                 return 0;
1025         }
1026
1027         if (!(commit_base = lookup_commit_reference(base)) ||
1028             !(commit_a = lookup_commit_reference(a)) ||
1029             !(commit_b = lookup_commit_reference(b))) {
1030                 MERGE_WARNING(path, "commits not present");
1031                 return 0;
1032         }
1033
1034         /* check whether both changes are forward */
1035         if (!in_merge_bases(commit_base, commit_a) ||
1036             !in_merge_bases(commit_base, commit_b)) {
1037                 MERGE_WARNING(path, "commits don't follow merge-base");
1038                 return 0;
1039         }
1040
1041         /* Case #1: a is contained in b or vice versa */
1042         if (in_merge_bases(commit_a, commit_b)) {
1043                 hashcpy(result, b);
1044                 return 1;
1045         }
1046         if (in_merge_bases(commit_b, commit_a)) {
1047                 hashcpy(result, a);
1048                 return 1;
1049         }
1050
1051         /*
1052          * Case #2: There are one or more merges that contain a and b in
1053          * the submodule. If there is only one, then present it as a
1054          * suggestion to the user, but leave it marked unmerged so the
1055          * user needs to confirm the resolution.
1056          */
1057
1058         /* Skip the search if makes no sense to the calling context.  */
1059         if (!search)
1060                 return 0;
1061
1062         /* find commit which merges them */
1063         parent_count = find_first_merges(&merges, path, commit_a, commit_b);
1064         switch (parent_count) {
1065         case 0:
1066                 MERGE_WARNING(path, "merge following commits not found");
1067                 break;
1068
1069         case 1:
1070                 MERGE_WARNING(path, "not fast-forward");
1071                 fprintf(stderr, "Found a possible merge resolution "
1072                                 "for the submodule:\n");
1073                 print_commit((struct commit *) merges.objects[0].item);
1074                 fprintf(stderr,
1075                         "If this is correct simply add it to the index "
1076                         "for example\n"
1077                         "by using:\n\n"
1078                         "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1079                         "which will accept this suggestion.\n",
1080                         sha1_to_hex(merges.objects[0].item->sha1), path);
1081                 break;
1082
1083         default:
1084                 MERGE_WARNING(path, "multiple merges found");
1085                 for (i = 0; i < merges.nr; i++)
1086                         print_commit((struct commit *) merges.objects[i].item);
1087         }
1088
1089         free(merges.objects);
1090         return 0;
1091 }
1092
1093 /* Update gitfile and core.worktree setting to connect work tree and git dir */
1094 void connect_work_tree_and_git_dir(const char *work_tree, const char *git_dir)
1095 {
1096         struct strbuf file_name = STRBUF_INIT;
1097         struct strbuf rel_path = STRBUF_INIT;
1098         const char *real_work_tree = xstrdup(real_path(work_tree));
1099         FILE *fp;
1100
1101         /* Update gitfile */
1102         strbuf_addf(&file_name, "%s/.git", work_tree);
1103         fp = fopen(file_name.buf, "w");
1104         if (!fp)
1105                 die(_("Could not create git link %s"), file_name.buf);
1106         fprintf(fp, "gitdir: %s\n", relative_path(git_dir, real_work_tree,
1107                                                   &rel_path));
1108         fclose(fp);
1109
1110         /* Update core.worktree setting */
1111         strbuf_reset(&file_name);
1112         strbuf_addf(&file_name, "%s/config", git_dir);
1113         if (git_config_set_in_file(file_name.buf, "core.worktree",
1114                                    relative_path(real_work_tree, git_dir,
1115                                                  &rel_path)))
1116                 die(_("Could not set core.worktree in %s"),
1117                     file_name.buf);
1118
1119         strbuf_release(&file_name);
1120         strbuf_release(&rel_path);
1121         free((void *)real_work_tree);
1122 }