submodule.c

   1 #include "cache.h"
   2 #include "submodule-config.h"
   3 #include "submodule.h"
   4 #include "dir.h"
   5 #include "diff.h"
   6 #include "commit.h"
   7 #include "revision.h"
   8 #include "run-command.h"
   9 #include "diffcore.h"
  10 #include "refs.h"
  11 #include "string-list.h"
  12 #include "sha1-array.h"
  13 #include "argv-array.h"
  14 #include "blob.h"
  15 #include "thread-utils.h"
  16 #include "quote.h"
  17
  18 static int config_fetch_recurse_submodules = RECURSE_SUBMODULES_ON_DEMAND;
  19 static int parallel_jobs = 1;
  20 static struct string_list changed_submodule_paths = STRING_LIST_INIT_NODUP;
  21 static int initialized_fetch_ref_tips;
  22 static struct sha1_array ref_tips_before_fetch;
  23 static struct sha1_array ref_tips_after_fetch;
  24
  25 /*
  26  * The following flag is set if the .gitmodules file is unmerged. We then
  27  * disable recursion for all submodules where .git/config doesn't have a
  28  * matching config entry because we can't guess what might be configured in
  29  * .gitmodules unless the user resolves the conflict. When a command line
  30  * option is given (which always overrides configuration) this flag will be
  31  * ignored.
  32  */
  33 static int gitmodules_is_unmerged;
  34
  35 /*
  36  * This flag is set if the .gitmodules file had unstaged modifications on
  37  * startup. This must be checked before allowing modifications to the
  38  * .gitmodules file with the intention to stage them later, because when
  39  * continuing we would stage the modifications the user didn't stage herself
  40  * too. That might change in a future version when we learn to stage the
  41  * changes we do ourselves without staging any previous modifications.
  42  */
  43 static int gitmodules_is_modified;
  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         const struct submodule *submodule;
  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         submodule = submodule_from_path(null_sha1, oldpath);
  67         if (!submodule || !submodule->name) {
  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, submodule->name);
  73         strbuf_addstr(&entry, ".path");
  74         if (git_config_set_in_file_gently(".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 /*
  85  * Try to remove the "submodule.<name>" section from .gitmodules where the given
  86  * path is configured. Return 0 only if a .gitmodules file was found, a section
  87  * with the correct path=<path> setting was found and we could remove it.
  88  */
  89 int remove_path_from_gitmodules(const char *path)
  90 {
  91         struct strbuf sect = STRBUF_INIT;
  92         const struct submodule *submodule;
  93
  94         if (!file_exists(".gitmodules")) /* Do nothing without .gitmodules */
  95                 return -1;
  96
  97         if (gitmodules_is_unmerged)
  98                 die(_("Cannot change unmerged .gitmodules, resolve merge conflicts first"));
  99
 100         submodule = submodule_from_path(null_sha1, path);
 101         if (!submodule || !submodule->name) {
 102                 warning(_("Could not find section in .gitmodules where path=%s"), path);
 103                 return -1;
 104         }
 105         strbuf_addstr(&sect, "submodule.");
 106         strbuf_addstr(&sect, submodule->name);
 107         if (git_config_rename_section_in_file(".gitmodules", sect.buf, NULL) < 0) {
 108                 /* Maybe the user already did that, don't error out here */
 109                 warning(_("Could not remove .gitmodules entry for %s"), path);
 110                 strbuf_release(&sect);
 111                 return -1;
 112         }
 113         strbuf_release(&sect);
 114         return 0;
 115 }
 116
 117 void stage_updated_gitmodules(void)
 118 {
 119         if (add_file_to_cache(".gitmodules", 0))
 120                 die(_("staging updated .gitmodules failed"));
 121 }
 122
 123 static int add_submodule_odb(const char *path)
 124 {
 125         struct strbuf objects_directory = STRBUF_INIT;
 126         struct alternate_object_database *alt_odb;
 127         int ret = 0;
 128         size_t alloc;
 129
 130         strbuf_git_path_submodule(&objects_directory, path, "objects/");
 131         if (!is_directory(objects_directory.buf)) {
 132                 ret = -1;
 133                 goto done;
 134         }
 135         /* avoid adding it twice */
 136         prepare_alt_odb();
 137         for (alt_odb = alt_odb_list; alt_odb; alt_odb = alt_odb->next)
 138                 if (alt_odb->name - alt_odb->base == objects_directory.len &&
 139                                 !strncmp(alt_odb->base, objects_directory.buf,
 140                                         objects_directory.len))
 141                         goto done;
 142
 143         alloc = st_add(objects_directory.len, 42); /* for "12/345..." sha1 */
 144         alt_odb = xmalloc(st_add(sizeof(*alt_odb), alloc));
 145         alt_odb->next = alt_odb_list;
 146         xsnprintf(alt_odb->base, alloc, "%s", objects_directory.buf);
 147         alt_odb->name = alt_odb->base + objects_directory.len;
 148         alt_odb->name[2] = '/';
 149         alt_odb->name[40] = '\0';
 150         alt_odb->name[41] = '\0';
 151         alt_odb_list = alt_odb;
 152
 153         /* add possible alternates from the submodule */
 154         read_info_alternates(objects_directory.buf, 0);
 155 done:
 156         strbuf_release(&objects_directory);
 157         return ret;
 158 }
 159
 160 void set_diffopt_flags_from_submodule_config(struct diff_options *diffopt,
 161                                              const char *path)
 162 {
 163         const struct submodule *submodule = submodule_from_path(null_sha1, path);
 164         if (submodule) {
 165                 if (submodule->ignore)
 166                         handle_ignore_submodules_arg(diffopt, submodule->ignore);
 167                 else if (gitmodules_is_unmerged)
 168                         DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
 169         }
 170 }
 171
 172 int submodule_config(const char *var, const char *value, void *cb)
 173 {
 174         if (!strcmp(var, "submodule.fetchjobs")) {
 175                 parallel_jobs = git_config_int(var, value);
 176                 if (parallel_jobs < 0)
 177                         die(_("negative values not allowed for submodule.fetchJobs"));
 178                 return 0;
 179         } else if (starts_with(var, "submodule."))
 180                 return parse_submodule_config_option(var, value);
 181         else if (!strcmp(var, "fetch.recursesubmodules")) {
 182                 config_fetch_recurse_submodules = parse_fetch_recurse_submodules_arg(var, value);
 183                 return 0;
 184         }
 185         return 0;
 186 }
 187
 188 void gitmodules_config(void)
 189 {
 190         const char *work_tree = get_git_work_tree();
 191         if (work_tree) {
 192                 struct strbuf gitmodules_path = STRBUF_INIT;
 193                 int pos;
 194                 strbuf_addstr(&gitmodules_path, work_tree);
 195                 strbuf_addstr(&gitmodules_path, "/.gitmodules");
 196                 if (read_cache() < 0)
 197                         die("index file corrupt");
 198                 pos = cache_name_pos(".gitmodules", 11);
 199                 if (pos < 0) { /* .gitmodules not found or isn't merged */
 200                         pos = -1 - pos;
 201                         if (active_nr > pos) {  /* there is a .gitmodules */
 202                                 const struct cache_entry *ce = active_cache[pos];
 203                                 if (ce_namelen(ce) == 11 &&
 204                                     !memcmp(ce->name, ".gitmodules", 11))
 205                                         gitmodules_is_unmerged = 1;
 206                         }
 207                 } else if (pos < active_nr) {
 208                         struct stat st;
 209                         if (lstat(".gitmodules", &st) == 0 &&
 210                             ce_match_stat(active_cache[pos], &st, 0) & DATA_CHANGED)
 211                                 gitmodules_is_modified = 1;
 212                 }
 213
 214                 if (!gitmodules_is_unmerged)
 215                         git_config_from_file(submodule_config, gitmodules_path.buf, NULL);
 216                 strbuf_release(&gitmodules_path);
 217         }
 218 }
 219
 220 int parse_submodule_update_strategy(const char *value,
 221                 struct submodule_update_strategy *dst)
 222 {
 223         free((void*)dst->command);
 224         dst->command = NULL;
 225         if (!strcmp(value, "none"))
 226                 dst->type = SM_UPDATE_NONE;
 227         else if (!strcmp(value, "checkout"))
 228                 dst->type = SM_UPDATE_CHECKOUT;
 229         else if (!strcmp(value, "rebase"))
 230                 dst->type = SM_UPDATE_REBASE;
 231         else if (!strcmp(value, "merge"))
 232                 dst->type = SM_UPDATE_MERGE;
 233         else if (skip_prefix(value, "!", &value)) {
 234                 dst->type = SM_UPDATE_COMMAND;
 235                 dst->command = xstrdup(value);
 236         } else
 237                 return -1;
 238         return 0;
 239 }
 240
 241 const char *submodule_strategy_to_string(const struct submodule_update_strategy *s)
 242 {
 243         struct strbuf sb = STRBUF_INIT;
 244         switch (s->type) {
 245         case SM_UPDATE_CHECKOUT:
 246                 return "checkout";
 247         case SM_UPDATE_MERGE:
 248                 return "merge";
 249         case SM_UPDATE_REBASE:
 250                 return "rebase";
 251         case SM_UPDATE_NONE:
 252                 return "none";
 253         case SM_UPDATE_UNSPECIFIED:
 254                 return NULL;
 255         case SM_UPDATE_COMMAND:
 256                 strbuf_addf(&sb, "!%s", s->command);
 257                 return strbuf_detach(&sb, NULL);
 258         }
 259         return NULL;
 260 }
 261
 262 void handle_ignore_submodules_arg(struct diff_options *diffopt,
 263                                   const char *arg)
 264 {
 265         DIFF_OPT_CLR(diffopt, IGNORE_SUBMODULES);
 266         DIFF_OPT_CLR(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 267         DIFF_OPT_CLR(diffopt, IGNORE_DIRTY_SUBMODULES);
 268
 269         if (!strcmp(arg, "all"))
 270                 DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
 271         else if (!strcmp(arg, "untracked"))
 272                 DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 273         else if (!strcmp(arg, "dirty"))
 274                 DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES);
 275         else if (strcmp(arg, "none"))
 276                 die("bad --ignore-submodules argument: %s", arg);
 277 }
 278
 279 static int prepare_submodule_summary(struct rev_info *rev, const char *path,
 280                 struct commit *left, struct commit *right,
 281                 int *fast_forward, int *fast_backward)
 282 {
 283         struct commit_list *merge_bases, *list;
 284
 285         init_revisions(rev, NULL);
 286         setup_revisions(0, NULL, rev, NULL);
 287         rev->left_right = 1;
 288         rev->first_parent_only = 1;
 289         left->object.flags |= SYMMETRIC_LEFT;
 290         add_pending_object(rev, &left->object, path);
 291         add_pending_object(rev, &right->object, path);
 292         merge_bases = get_merge_bases(left, right);
 293         if (merge_bases) {
 294                 if (merge_bases->item == left)
 295                         *fast_forward = 1;
 296                 else if (merge_bases->item == right)
 297                         *fast_backward = 1;
 298         }
 299         for (list = merge_bases; list; list = list->next) {
 300                 list->item->object.flags |= UNINTERESTING;
 301                 add_pending_object(rev, &list->item->object,
 302                         oid_to_hex(&list->item->object.oid));
 303         }
 304         return prepare_revision_walk(rev);
 305 }
 306
 307 static void print_submodule_summary(struct rev_info *rev, FILE *f,
 308                 const char *line_prefix,
 309                 const char *del, const char *add, const char *reset)
 310 {
 311         static const char format[] = "  %m %s";
 312         struct strbuf sb = STRBUF_INIT;
 313         struct commit *commit;
 314
 315         while ((commit = get_revision(rev))) {
 316                 struct pretty_print_context ctx = {0};
 317                 ctx.date_mode = rev->date_mode;
 318                 ctx.output_encoding = get_log_output_encoding();
 319                 strbuf_setlen(&sb, 0);
 320                 strbuf_addstr(&sb, line_prefix);
 321                 if (commit->object.flags & SYMMETRIC_LEFT) {
 322                         if (del)
 323                                 strbuf_addstr(&sb, del);
 324                 }
 325                 else if (add)
 326                         strbuf_addstr(&sb, add);
 327                 format_commit_message(commit, format, &sb, &ctx);
 328                 if (reset)
 329                         strbuf_addstr(&sb, reset);
 330                 strbuf_addch(&sb, '\n');
 331                 fprintf(f, "%s", sb.buf);
 332         }
 333         strbuf_release(&sb);
 334 }
 335
 336 void show_submodule_summary(FILE *f, const char *path,
 337                 const char *line_prefix,
 338                 unsigned char one[20], unsigned char two[20],
 339                 unsigned dirty_submodule, const char *meta,
 340                 const char *del, const char *add, const char *reset)
 341 {
 342         struct rev_info rev;
 343         struct commit *left = NULL, *right = NULL;
 344         const char *message = NULL;
 345         struct strbuf sb = STRBUF_INIT;
 346         int fast_forward = 0, fast_backward = 0;
 347
 348         if (is_null_sha1(two))
 349                 message = "(submodule deleted)";
 350         else if (add_submodule_odb(path))
 351                 message = "(not checked out)";
 352         else if (is_null_sha1(one))
 353                 message = "(new submodule)";
 354         else if (!(left = lookup_commit_reference(one)) ||
 355                  !(right = lookup_commit_reference(two)))
 356                 message = "(commits not present)";
 357         else if (prepare_submodule_summary(&rev, path, left, right,
 358                                            &fast_forward, &fast_backward))
 359                 message = "(revision walker failed)";
 360
 361         if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
 362                 fprintf(f, "%sSubmodule %s contains untracked content\n",
 363                         line_prefix, path);
 364         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
 365                 fprintf(f, "%sSubmodule %s contains modified content\n",
 366                         line_prefix, path);
 367
 368         if (!hashcmp(one, two)) {
 369                 strbuf_release(&sb);
 370                 return;
 371         }
 372
 373         strbuf_addf(&sb, "%s%sSubmodule %s ", line_prefix, meta, path);
 374         strbuf_add_unique_abbrev(&sb, one, DEFAULT_ABBREV);
 375         strbuf_addstr(&sb, (fast_backward || fast_forward) ? ".." : "...");
 376         strbuf_add_unique_abbrev(&sb, two, DEFAULT_ABBREV);
 377         if (message)
 378                 strbuf_addf(&sb, " %s%s\n", message, reset);
 379         else
 380                 strbuf_addf(&sb, "%s:%s\n", fast_backward ? " (rewind)" : "", reset);
 381         fwrite(sb.buf, sb.len, 1, f);
 382
 383         if (!message) /* only NULL if we succeeded in setting up the walk */
 384                 print_submodule_summary(&rev, f, line_prefix, del, add, reset);
 385         if (left)
 386                 clear_commit_marks(left, ~0);
 387         if (right)
 388                 clear_commit_marks(right, ~0);
 389
 390         strbuf_release(&sb);
 391 }
 392
 393 void set_config_fetch_recurse_submodules(int value)
 394 {
 395         config_fetch_recurse_submodules = value;
 396 }
 397
 398 static int has_remote(const char *refname, const struct object_id *oid,
 399                       int flags, void *cb_data)
 400 {
 401         return 1;
 402 }
 403
 404 static int submodule_needs_pushing(const char *path, const unsigned char sha1[20])
 405 {
 406         if (add_submodule_odb(path) || !lookup_commit_reference(sha1))
 407                 return 0;
 408
 409         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 410                 struct child_process cp = CHILD_PROCESS_INIT;
 411                 const char *argv[] = {"rev-list", NULL, "--not", "--remotes", "-n", "1" , NULL};
 412                 struct strbuf buf = STRBUF_INIT;
 413                 int needs_pushing = 0;
 414
 415                 argv[1] = sha1_to_hex(sha1);
 416                 cp.argv = argv;
 417                 prepare_submodule_repo_env(&cp.env_array);
 418                 cp.git_cmd = 1;
 419                 cp.no_stdin = 1;
 420                 cp.out = -1;
 421                 cp.dir = path;
 422                 if (start_command(&cp))
 423                         die("Could not run 'git rev-list %s --not --remotes -n 1' command in submodule %s",
 424                                 sha1_to_hex(sha1), path);
 425                 if (strbuf_read(&buf, cp.out, 41))
 426                         needs_pushing = 1;
 427                 finish_command(&cp);
 428                 close(cp.out);
 429                 strbuf_release(&buf);
 430                 return needs_pushing;
 431         }
 432
 433         return 0;
 434 }
 435
 436 static void collect_submodules_from_diff(struct diff_queue_struct *q,
 437                                          struct diff_options *options,
 438                                          void *data)
 439 {
 440         int i;
 441         struct string_list *needs_pushing = data;
 442
 443         for (i = 0; i < q->nr; i++) {
 444                 struct diff_filepair *p = q->queue[i];
 445                 if (!S_ISGITLINK(p->two->mode))
 446                         continue;
 447                 if (submodule_needs_pushing(p->two->path, p->two->oid.hash))
 448                         string_list_insert(needs_pushing, p->two->path);
 449         }
 450 }
 451
 452 static void find_unpushed_submodule_commits(struct commit *commit,
 453                 struct string_list *needs_pushing)
 454 {
 455         struct rev_info rev;
 456
 457         init_revisions(&rev, NULL);
 458         rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
 459         rev.diffopt.format_callback = collect_submodules_from_diff;
 460         rev.diffopt.format_callback_data = needs_pushing;
 461         diff_tree_combined_merge(commit, 1, &rev);
 462 }
 463
 464 int find_unpushed_submodules(unsigned char new_sha1[20],
 465                 const char *remotes_name, struct string_list *needs_pushing)
 466 {
 467         struct rev_info rev;
 468         struct commit *commit;
 469         const char *argv[] = {NULL, NULL, "--not", "NULL", NULL};
 470         int argc = ARRAY_SIZE(argv) - 1;
 471         char *sha1_copy;
 472
 473         struct strbuf remotes_arg = STRBUF_INIT;
 474
 475         strbuf_addf(&remotes_arg, "--remotes=%s", remotes_name);
 476         init_revisions(&rev, NULL);
 477         sha1_copy = xstrdup(sha1_to_hex(new_sha1));
 478         argv[1] = sha1_copy;
 479         argv[3] = remotes_arg.buf;
 480         setup_revisions(argc, argv, &rev, NULL);
 481         if (prepare_revision_walk(&rev))
 482                 die("revision walk setup failed");
 483
 484         while ((commit = get_revision(&rev)) != NULL)
 485                 find_unpushed_submodule_commits(commit, needs_pushing);
 486
 487         reset_revision_walk();
 488         free(sha1_copy);
 489         strbuf_release(&remotes_arg);
 490
 491         return needs_pushing->nr;
 492 }
 493
 494 static int push_submodule(const char *path)
 495 {
 496         if (add_submodule_odb(path))
 497                 return 1;
 498
 499         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 500                 struct child_process cp = CHILD_PROCESS_INIT;
 501                 const char *argv[] = {"push", NULL};
 502
 503                 cp.argv = argv;
 504                 prepare_submodule_repo_env(&cp.env_array);
 505                 cp.git_cmd = 1;
 506                 cp.no_stdin = 1;
 507                 cp.dir = path;
 508                 if (run_command(&cp))
 509                         return 0;
 510                 close(cp.out);
 511         }
 512
 513         return 1;
 514 }
 515
 516 int push_unpushed_submodules(unsigned char new_sha1[20], const char *remotes_name)
 517 {
 518         int i, ret = 1;
 519         struct string_list needs_pushing = STRING_LIST_INIT_DUP;
 520
 521         if (!find_unpushed_submodules(new_sha1, remotes_name, &needs_pushing))
 522                 return 1;
 523
 524         for (i = 0; i < needs_pushing.nr; i++) {
 525                 const char *path = needs_pushing.items[i].string;
 526                 fprintf(stderr, "Pushing submodule '%s'\n", path);
 527                 if (!push_submodule(path)) {
 528                         fprintf(stderr, "Unable to push submodule '%s'\n", path);
 529                         ret = 0;
 530                 }
 531         }
 532
 533         string_list_clear(&needs_pushing, 0);
 534
 535         return ret;
 536 }
 537
 538 static int is_submodule_commit_present(const char *path, unsigned char sha1[20])
 539 {
 540         int is_present = 0;
 541         if (!add_submodule_odb(path) && lookup_commit_reference(sha1)) {
 542                 /* Even if the submodule is checked out and the commit is
 543                  * present, make sure it is reachable from a ref. */
 544                 struct child_process cp = CHILD_PROCESS_INIT;
 545                 const char *argv[] = {"rev-list", "-n", "1", NULL, "--not", "--all", NULL};
 546                 struct strbuf buf = STRBUF_INIT;
 547
 548                 argv[3] = sha1_to_hex(sha1);
 549                 cp.argv = argv;
 550                 prepare_submodule_repo_env(&cp.env_array);
 551                 cp.git_cmd = 1;
 552                 cp.no_stdin = 1;
 553                 cp.dir = path;
 554                 if (!capture_command(&cp, &buf, 1024) && !buf.len)
 555                         is_present = 1;
 556
 557                 strbuf_release(&buf);
 558         }
 559         return is_present;
 560 }
 561
 562 static void submodule_collect_changed_cb(struct diff_queue_struct *q,
 563                                          struct diff_options *options,
 564                                          void *data)
 565 {
 566         int i;
 567         for (i = 0; i < q->nr; i++) {
 568                 struct diff_filepair *p = q->queue[i];
 569                 if (!S_ISGITLINK(p->two->mode))
 570                         continue;
 571
 572                 if (S_ISGITLINK(p->one->mode)) {
 573                         /* NEEDSWORK: We should honor the name configured in
 574                          * the .gitmodules file of the commit we are examining
 575                          * here to be able to correctly follow submodules
 576                          * being moved around. */
 577                         struct string_list_item *path;
 578                         path = unsorted_string_list_lookup(&changed_submodule_paths, p->two->path);
 579                         if (!path && !is_submodule_commit_present(p->two->path, p->two->oid.hash))
 580                                 string_list_append(&changed_submodule_paths, xstrdup(p->two->path));
 581                 } else {
 582                         /* Submodule is new or was moved here */
 583                         /* NEEDSWORK: When the .git directories of submodules
 584                          * live inside the superprojects .git directory some
 585                          * day we should fetch new submodules directly into
 586                          * that location too when config or options request
 587                          * that so they can be checked out from there. */
 588                         continue;
 589                 }
 590         }
 591 }
 592
 593 static int add_sha1_to_array(const char *ref, const struct object_id *oid,
 594                              int flags, void *data)
 595 {
 596         sha1_array_append(data, oid->hash);
 597         return 0;
 598 }
 599
 600 void check_for_new_submodule_commits(unsigned char new_sha1[20])
 601 {
 602         if (!initialized_fetch_ref_tips) {
 603                 for_each_ref(add_sha1_to_array, &ref_tips_before_fetch);
 604                 initialized_fetch_ref_tips = 1;
 605         }
 606
 607         sha1_array_append(&ref_tips_after_fetch, new_sha1);
 608 }
 609
 610 static void add_sha1_to_argv(const unsigned char sha1[20], void *data)
 611 {
 612         argv_array_push(data, sha1_to_hex(sha1));
 613 }
 614
 615 static void calculate_changed_submodule_paths(void)
 616 {
 617         struct rev_info rev;
 618         struct commit *commit;
 619         struct argv_array argv = ARGV_ARRAY_INIT;
 620
 621         /* No need to check if there are no submodules configured */
 622         if (!submodule_from_path(NULL, NULL))
 623                 return;
 624
 625         init_revisions(&rev, NULL);
 626         argv_array_push(&argv, "--"); /* argv[0] program name */
 627         sha1_array_for_each_unique(&ref_tips_after_fetch,
 628                                    add_sha1_to_argv, &argv);
 629         argv_array_push(&argv, "--not");
 630         sha1_array_for_each_unique(&ref_tips_before_fetch,
 631                                    add_sha1_to_argv, &argv);
 632         setup_revisions(argv.argc, argv.argv, &rev, NULL);
 633         if (prepare_revision_walk(&rev))
 634                 die("revision walk setup failed");
 635
 636         /*
 637          * Collect all submodules (whether checked out or not) for which new
 638          * commits have been recorded upstream in "changed_submodule_paths".
 639          */
 640         while ((commit = get_revision(&rev))) {
 641                 struct commit_list *parent = commit->parents;
 642                 while (parent) {
 643                         struct diff_options diff_opts;
 644                         diff_setup(&diff_opts);
 645                         DIFF_OPT_SET(&diff_opts, RECURSIVE);
 646                         diff_opts.output_format |= DIFF_FORMAT_CALLBACK;
 647                         diff_opts.format_callback = submodule_collect_changed_cb;
 648                         diff_setup_done(&diff_opts);
 649                         diff_tree_sha1(parent->item->object.oid.hash, commit->object.oid.hash, "", &diff_opts);
 650                         diffcore_std(&diff_opts);
 651                         diff_flush(&diff_opts);
 652                         parent = parent->next;
 653                 }
 654         }
 655
 656         argv_array_clear(&argv);
 657         sha1_array_clear(&ref_tips_before_fetch);
 658         sha1_array_clear(&ref_tips_after_fetch);
 659         initialized_fetch_ref_tips = 0;
 660 }
 661
 662 struct submodule_parallel_fetch {
 663         int count;
 664         struct argv_array args;
 665         const char *work_tree;
 666         const char *prefix;
 667         int command_line_option;
 668         int quiet;
 669         int result;
 670 };
 671 #define SPF_INIT {0, ARGV_ARRAY_INIT, NULL, NULL, 0, 0, 0}
 672
 673 static int get_next_submodule(struct child_process *cp,
 674                               struct strbuf *err, void *data, void **task_cb)
 675 {
 676         int ret = 0;
 677         struct submodule_parallel_fetch *spf = data;
 678
 679         for (; spf->count < active_nr; spf->count++) {
 680                 struct strbuf submodule_path = STRBUF_INIT;
 681                 struct strbuf submodule_git_dir = STRBUF_INIT;
 682                 struct strbuf submodule_prefix = STRBUF_INIT;
 683                 const struct cache_entry *ce = active_cache[spf->count];
 684                 const char *git_dir, *default_argv;
 685                 const struct submodule *submodule;
 686
 687                 if (!S_ISGITLINK(ce->ce_mode))
 688                         continue;
 689
 690                 submodule = submodule_from_path(null_sha1, ce->name);
 691                 if (!submodule)
 692                         submodule = submodule_from_name(null_sha1, ce->name);
 693
 694                 default_argv = "yes";
 695                 if (spf->command_line_option == RECURSE_SUBMODULES_DEFAULT) {
 696                         if (submodule &&
 697                             submodule->fetch_recurse !=
 698                                                 RECURSE_SUBMODULES_NONE) {
 699                                 if (submodule->fetch_recurse ==
 700                                                 RECURSE_SUBMODULES_OFF)
 701                                         continue;
 702                                 if (submodule->fetch_recurse ==
 703                                                 RECURSE_SUBMODULES_ON_DEMAND) {
 704                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 705                                                 continue;
 706                                         default_argv = "on-demand";
 707                                 }
 708                         } else {
 709                                 if ((config_fetch_recurse_submodules == RECURSE_SUBMODULES_OFF) ||
 710                                     gitmodules_is_unmerged)
 711                                         continue;
 712                                 if (config_fetch_recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) {
 713                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 714                                                 continue;
 715                                         default_argv = "on-demand";
 716                                 }
 717                         }
 718                 } else if (spf->command_line_option == RECURSE_SUBMODULES_ON_DEMAND) {
 719                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 720                                 continue;
 721                         default_argv = "on-demand";
 722                 }
 723
 724                 strbuf_addf(&submodule_path, "%s/%s", spf->work_tree, ce->name);
 725                 strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
 726                 strbuf_addf(&submodule_prefix, "%s%s/", spf->prefix, ce->name);
 727                 git_dir = read_gitfile(submodule_git_dir.buf);
 728                 if (!git_dir)
 729                         git_dir = submodule_git_dir.buf;
 730                 if (is_directory(git_dir)) {
 731                         child_process_init(cp);
 732                         cp->dir = strbuf_detach(&submodule_path, NULL);
 733                         prepare_submodule_repo_env(&cp->env_array);
 734                         cp->git_cmd = 1;
 735                         if (!spf->quiet)
 736                                 strbuf_addf(err, "Fetching submodule %s%s\n",
 737                                             spf->prefix, ce->name);
 738                         argv_array_init(&cp->args);
 739                         argv_array_pushv(&cp->args, spf->args.argv);
 740                         argv_array_push(&cp->args, default_argv);
 741                         argv_array_push(&cp->args, "--submodule-prefix");
 742                         argv_array_push(&cp->args, submodule_prefix.buf);
 743                         ret = 1;
 744                 }
 745                 strbuf_release(&submodule_path);
 746                 strbuf_release(&submodule_git_dir);
 747                 strbuf_release(&submodule_prefix);
 748                 if (ret) {
 749                         spf->count++;
 750                         return 1;
 751                 }
 752         }
 753         return 0;
 754 }
 755
 756 static int fetch_start_failure(struct strbuf *err,
 757                                void *cb, void *task_cb)
 758 {
 759         struct submodule_parallel_fetch *spf = cb;
 760
 761         spf->result = 1;
 762
 763         return 0;
 764 }
 765
 766 static int fetch_finish(int retvalue, struct strbuf *err,
 767                         void *cb, void *task_cb)
 768 {
 769         struct submodule_parallel_fetch *spf = cb;
 770
 771         if (retvalue)
 772                 spf->result = 1;
 773
 774         return 0;
 775 }
 776
 777 int fetch_populated_submodules(const struct argv_array *options,
 778                                const char *prefix, int command_line_option,
 779                                int quiet, int max_parallel_jobs)
 780 {
 781         int i;
 782         struct submodule_parallel_fetch spf = SPF_INIT;
 783
 784         spf.work_tree = get_git_work_tree();
 785         spf.command_line_option = command_line_option;
 786         spf.quiet = quiet;
 787         spf.prefix = prefix;
 788
 789         if (!spf.work_tree)
 790                 goto out;
 791
 792         if (read_cache() < 0)
 793                 die("index file corrupt");
 794
 795         argv_array_push(&spf.args, "fetch");
 796         for (i = 0; i < options->argc; i++)
 797                 argv_array_push(&spf.args, options->argv[i]);
 798         argv_array_push(&spf.args, "--recurse-submodules-default");
 799         /* default value, "--submodule-prefix" and its value are added later */
 800
 801         if (max_parallel_jobs < 0)
 802                 max_parallel_jobs = parallel_jobs;
 803
 804         calculate_changed_submodule_paths();
 805         run_processes_parallel(max_parallel_jobs,
 806                                get_next_submodule,
 807                                fetch_start_failure,
 808                                fetch_finish,
 809                                &spf);
 810
 811         argv_array_clear(&spf.args);
 812 out:
 813         string_list_clear(&changed_submodule_paths, 1);
 814         return spf.result;
 815 }
 816
 817 unsigned is_submodule_modified(const char *path, int ignore_untracked)
 818 {
 819         ssize_t len;
 820         struct child_process cp = CHILD_PROCESS_INIT;
 821         const char *argv[] = {
 822                 "status",
 823                 "--porcelain",
 824                 NULL,
 825                 NULL,
 826         };
 827         struct strbuf buf = STRBUF_INIT;
 828         unsigned dirty_submodule = 0;
 829         const char *line, *next_line;
 830         const char *git_dir;
 831
 832         strbuf_addf(&buf, "%s/.git", path);
 833         git_dir = read_gitfile(buf.buf);
 834         if (!git_dir)
 835                 git_dir = buf.buf;
 836         if (!is_directory(git_dir)) {
 837                 strbuf_release(&buf);
 838                 /* The submodule is not checked out, so it is not modified */
 839                 return 0;
 840
 841         }
 842         strbuf_reset(&buf);
 843
 844         if (ignore_untracked)
 845                 argv[2] = "-uno";
 846
 847         cp.argv = argv;
 848         prepare_submodule_repo_env(&cp.env_array);
 849         cp.git_cmd = 1;
 850         cp.no_stdin = 1;
 851         cp.out = -1;
 852         cp.dir = path;
 853         if (start_command(&cp))
 854                 die("Could not run 'git status --porcelain' in submodule %s", path);
 855
 856         len = strbuf_read(&buf, cp.out, 1024);
 857         line = buf.buf;
 858         while (len > 2) {
 859                 if ((line[0] == '?') && (line[1] == '?')) {
 860                         dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
 861                         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
 862                                 break;
 863                 } else {
 864                         dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
 865                         if (ignore_untracked ||
 866                             (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED))
 867                                 break;
 868                 }
 869                 next_line = strchr(line, '\n');
 870                 if (!next_line)
 871                         break;
 872                 next_line++;
 873                 len -= (next_line - line);
 874                 line = next_line;
 875         }
 876         close(cp.out);
 877
 878         if (finish_command(&cp))
 879                 die("'git status --porcelain' failed in submodule %s", path);
 880
 881         strbuf_release(&buf);
 882         return dirty_submodule;
 883 }
 884
 885 int submodule_uses_gitfile(const char *path)
 886 {
 887         struct child_process cp = CHILD_PROCESS_INIT;
 888         const char *argv[] = {
 889                 "submodule",
 890                 "foreach",
 891                 "--quiet",
 892                 "--recursive",
 893                 "test -f .git",
 894                 NULL,
 895         };
 896         struct strbuf buf = STRBUF_INIT;
 897         const char *git_dir;
 898
 899         strbuf_addf(&buf, "%s/.git", path);
 900         git_dir = read_gitfile(buf.buf);
 901         if (!git_dir) {
 902                 strbuf_release(&buf);
 903                 return 0;
 904         }
 905         strbuf_release(&buf);
 906
 907         /* Now test that all nested submodules use a gitfile too */
 908         cp.argv = argv;
 909         prepare_submodule_repo_env(&cp.env_array);
 910         cp.git_cmd = 1;
 911         cp.no_stdin = 1;
 912         cp.no_stderr = 1;
 913         cp.no_stdout = 1;
 914         cp.dir = path;
 915         if (run_command(&cp))
 916                 return 0;
 917
 918         return 1;
 919 }
 920
 921 int ok_to_remove_submodule(const char *path)
 922 {
 923         ssize_t len;
 924         struct child_process cp = CHILD_PROCESS_INIT;
 925         const char *argv[] = {
 926                 "status",
 927                 "--porcelain",
 928                 "-u",
 929                 "--ignore-submodules=none",
 930                 NULL,
 931         };
 932         struct strbuf buf = STRBUF_INIT;
 933         int ok_to_remove = 1;
 934
 935         if (!file_exists(path) || is_empty_dir(path))
 936                 return 1;
 937
 938         if (!submodule_uses_gitfile(path))
 939                 return 0;
 940
 941         cp.argv = argv;
 942         prepare_submodule_repo_env(&cp.env_array);
 943         cp.git_cmd = 1;
 944         cp.no_stdin = 1;
 945         cp.out = -1;
 946         cp.dir = path;
 947         if (start_command(&cp))
 948                 die("Could not run 'git status --porcelain -uall --ignore-submodules=none' in submodule %s", path);
 949
 950         len = strbuf_read(&buf, cp.out, 1024);
 951         if (len > 2)
 952                 ok_to_remove = 0;
 953         close(cp.out);
 954
 955         if (finish_command(&cp))
 956                 die("'git status --porcelain -uall --ignore-submodules=none' failed in submodule %s", path);
 957
 958         strbuf_release(&buf);
 959         return ok_to_remove;
 960 }
 961
 962 static int find_first_merges(struct object_array *result, const char *path,
 963                 struct commit *a, struct commit *b)
 964 {
 965         int i, j;
 966         struct object_array merges = OBJECT_ARRAY_INIT;
 967         struct commit *commit;
 968         int contains_another;
 969
 970         char merged_revision[42];
 971         const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
 972                                    "--all", merged_revision, NULL };
 973         struct rev_info revs;
 974         struct setup_revision_opt rev_opts;
 975
 976         memset(result, 0, sizeof(struct object_array));
 977         memset(&rev_opts, 0, sizeof(rev_opts));
 978
 979         /* get all revisions that merge commit a */
 980         snprintf(merged_revision, sizeof(merged_revision), "^%s",
 981                         oid_to_hex(&a->object.oid));
 982         init_revisions(&revs, NULL);
 983         rev_opts.submodule = path;
 984         setup_revisions(ARRAY_SIZE(rev_args)-1, rev_args, &revs, &rev_opts);
 985
 986         /* save all revisions from the above list that contain b */
 987         if (prepare_revision_walk(&revs))
 988                 die("revision walk setup failed");
 989         while ((commit = get_revision(&revs)) != NULL) {
 990                 struct object *o = &(commit->object);
 991                 if (in_merge_bases(b, commit))
 992                         add_object_array(o, NULL, &merges);
 993         }
 994         reset_revision_walk();
 995
 996         /* Now we've got all merges that contain a and b. Prune all
 997          * merges that contain another found merge and save them in
 998          * result.
 999          */
1000         for (i = 0; i < merges.nr; i++) {
1001                 struct commit *m1 = (struct commit *) merges.objects[i].item;
1002
1003                 contains_another = 0;
1004                 for (j = 0; j < merges.nr; j++) {
1005                         struct commit *m2 = (struct commit *) merges.objects[j].item;
1006                         if (i != j && in_merge_bases(m2, m1)) {
1007                                 contains_another = 1;
1008                                 break;
1009                         }
1010                 }
1011
1012                 if (!contains_another)
1013                         add_object_array(merges.objects[i].item, NULL, result);
1014         }
1015
1016         free(merges.objects);
1017         return result->nr;
1018 }
1019
1020 static void print_commit(struct commit *commit)
1021 {
1022         struct strbuf sb = STRBUF_INIT;
1023         struct pretty_print_context ctx = {0};
1024         ctx.date_mode.type = DATE_NORMAL;
1025         format_commit_message(commit, " %h: %m %s", &sb, &ctx);
1026         fprintf(stderr, "%s\n", sb.buf);
1027         strbuf_release(&sb);
1028 }
1029
1030 #define MERGE_WARNING(path, msg) \
1031         warning("Failed to merge submodule %s (%s)", path, msg);
1032
1033 int merge_submodule(unsigned char result[20], const char *path,
1034                     const unsigned char base[20], const unsigned char a[20],
1035                     const unsigned char b[20], int search)
1036 {
1037         struct commit *commit_base, *commit_a, *commit_b;
1038         int parent_count;
1039         struct object_array merges;
1040
1041         int i;
1042
1043         /* store a in result in case we fail */
1044         hashcpy(result, a);
1045
1046         /* we can not handle deletion conflicts */
1047         if (is_null_sha1(base))
1048                 return 0;
1049         if (is_null_sha1(a))
1050                 return 0;
1051         if (is_null_sha1(b))
1052                 return 0;
1053
1054         if (add_submodule_odb(path)) {
1055                 MERGE_WARNING(path, "not checked out");
1056                 return 0;
1057         }
1058
1059         if (!(commit_base = lookup_commit_reference(base)) ||
1060             !(commit_a = lookup_commit_reference(a)) ||
1061             !(commit_b = lookup_commit_reference(b))) {
1062                 MERGE_WARNING(path, "commits not present");
1063                 return 0;
1064         }
1065
1066         /* check whether both changes are forward */
1067         if (!in_merge_bases(commit_base, commit_a) ||
1068             !in_merge_bases(commit_base, commit_b)) {
1069                 MERGE_WARNING(path, "commits don't follow merge-base");
1070                 return 0;
1071         }
1072
1073         /* Case #1: a is contained in b or vice versa */
1074         if (in_merge_bases(commit_a, commit_b)) {
1075                 hashcpy(result, b);
1076                 return 1;
1077         }
1078         if (in_merge_bases(commit_b, commit_a)) {
1079                 hashcpy(result, a);
1080                 return 1;
1081         }
1082
1083         /*
1084          * Case #2: There are one or more merges that contain a and b in
1085          * the submodule. If there is only one, then present it as a
1086          * suggestion to the user, but leave it marked unmerged so the
1087          * user needs to confirm the resolution.
1088          */
1089
1090         /* Skip the search if makes no sense to the calling context.  */
1091         if (!search)
1092                 return 0;
1093
1094         /* find commit which merges them */
1095         parent_count = find_first_merges(&merges, path, commit_a, commit_b);
1096         switch (parent_count) {
1097         case 0:
1098                 MERGE_WARNING(path, "merge following commits not found");
1099                 break;
1100
1101         case 1:
1102                 MERGE_WARNING(path, "not fast-forward");
1103                 fprintf(stderr, "Found a possible merge resolution "
1104                                 "for the submodule:\n");
1105                 print_commit((struct commit *) merges.objects[0].item);
1106                 fprintf(stderr,
1107                         "If this is correct simply add it to the index "
1108                         "for example\n"
1109                         "by using:\n\n"
1110                         "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1111                         "which will accept this suggestion.\n",
1112                         oid_to_hex(&merges.objects[0].item->oid), path);
1113                 break;
1114
1115         default:
1116                 MERGE_WARNING(path, "multiple merges found");
1117                 for (i = 0; i < merges.nr; i++)
1118                         print_commit((struct commit *) merges.objects[i].item);
1119         }
1120
1121         free(merges.objects);
1122         return 0;
1123 }
1124
1125 /* Update gitfile and core.worktree setting to connect work tree and git dir */
1126 void connect_work_tree_and_git_dir(const char *work_tree, const char *git_dir)
1127 {
1128         struct strbuf file_name = STRBUF_INIT;
1129         struct strbuf rel_path = STRBUF_INIT;
1130         const char *real_work_tree = xstrdup(real_path(work_tree));
1131
1132         /* Update gitfile */
1133         strbuf_addf(&file_name, "%s/.git", work_tree);
1134         write_file(file_name.buf, "gitdir: %s",
1135                    relative_path(git_dir, real_work_tree, &rel_path));
1136
1137         /* Update core.worktree setting */
1138         strbuf_reset(&file_name);
1139         strbuf_addf(&file_name, "%s/config", git_dir);
1140         git_config_set_in_file(file_name.buf, "core.worktree",
1141                                relative_path(real_work_tree, git_dir,
1142                                              &rel_path));
1143
1144         strbuf_release(&file_name);
1145         strbuf_release(&rel_path);
1146         free((void *)real_work_tree);
1147 }
1148
1149 int parallel_submodules(void)
1150 {
1151         return parallel_jobs;
1152 }
1153
1154 void prepare_submodule_repo_env(struct argv_array *out)
1155 {
1156         const char * const *var;
1157
1158         for (var = local_repo_env; *var; var++) {
1159                 if (strcmp(*var, CONFIG_DATA_ENVIRONMENT))
1160                         argv_array_push(out, *var);
1161         }
1162         argv_array_push(out, "GIT_DIR=.git");
1163 }