builtin/submodule--helper.c

   1 #include "builtin.h"
   2 #include "cache.h"
   3 #include "parse-options.h"
   4 #include "quote.h"
   5 #include "pathspec.h"
   6 #include "dir.h"
   7 #include "utf8.h"
   8 #include "submodule.h"
   9 #include "submodule-config.h"
  10 #include "string-list.h"
  11 #include "run-command.h"
  12 #include "remote.h"
  13 #include "refs.h"
  14 #include "connect.h"
  15
  16 static char *get_default_remote(void)
  17 {
  18         char *dest = NULL, *ret;
  19         unsigned char sha1[20];
  20         struct strbuf sb = STRBUF_INIT;
  21         const char *refname = resolve_ref_unsafe("HEAD", 0, sha1, NULL);
  22
  23         if (!refname)
  24                 die(_("No such ref: %s"), "HEAD");
  25
  26         /* detached HEAD */
  27         if (!strcmp(refname, "HEAD"))
  28                 return xstrdup("origin");
  29
  30         if (!skip_prefix(refname, "refs/heads/", &refname))
  31                 die(_("Expecting a full ref name, got %s"), refname);
  32
  33         strbuf_addf(&sb, "branch.%s.remote", refname);
  34         if (git_config_get_string(sb.buf, &dest))
  35                 ret = xstrdup("origin");
  36         else
  37                 ret = dest;
  38
  39         strbuf_release(&sb);
  40         return ret;
  41 }
  42
  43 static int starts_with_dot_slash(const char *str)
  44 {
  45         return str[0] == '.' && is_dir_sep(str[1]);
  46 }
  47
  48 static int starts_with_dot_dot_slash(const char *str)
  49 {
  50         return str[0] == '.' && str[1] == '.' && is_dir_sep(str[2]);
  51 }
  52
  53 /*
  54  * Returns 1 if it was the last chop before ':'.
  55  */
  56 static int chop_last_dir(char **remoteurl, int is_relative)
  57 {
  58         char *rfind = find_last_dir_sep(*remoteurl);
  59         if (rfind) {
  60                 *rfind = '\0';
  61                 return 0;
  62         }
  63
  64         rfind = strrchr(*remoteurl, ':');
  65         if (rfind) {
  66                 *rfind = '\0';
  67                 return 1;
  68         }
  69
  70         if (is_relative || !strcmp(".", *remoteurl))
  71                 die(_("cannot strip one component off url '%s'"),
  72                         *remoteurl);
  73
  74         free(*remoteurl);
  75         *remoteurl = xstrdup(".");
  76         return 0;
  77 }
  78
  79 /*
  80  * The `url` argument is the URL that navigates to the submodule origin
  81  * repo. When relative, this URL is relative to the superproject origin
  82  * URL repo. The `up_path` argument, if specified, is the relative
  83  * path that navigates from the submodule working tree to the superproject
  84  * working tree. Returns the origin URL of the submodule.
  85  *
  86  * Return either an absolute URL or filesystem path (if the superproject
  87  * origin URL is an absolute URL or filesystem path, respectively) or a
  88  * relative file system path (if the superproject origin URL is a relative
  89  * file system path).
  90  *
  91  * When the output is a relative file system path, the path is either
  92  * relative to the submodule working tree, if up_path is specified, or to
  93  * the superproject working tree otherwise.
  94  *
  95  * NEEDSWORK: This works incorrectly on the domain and protocol part.
  96  * remote_url      url              outcome          expectation
  97  * http://a.com/b  ../c             http://a.com/c   as is
  98  * http://a.com/b/ ../c             http://a.com/c   same as previous line, but
  99  *                                                   ignore trailing slash in url
 100  * http://a.com/b  ../../c          http://c         error out
 101  * http://a.com/b  ../../../c       http:/c          error out
 102  * http://a.com/b  ../../../../c    http:c           error out
 103  * http://a.com/b  ../../../../../c    .:c           error out
 104  * NEEDSWORK: Given how chop_last_dir() works, this function is broken
 105  * when a local part has a colon in its path component, too.
 106  */
 107 static char *relative_url(const char *remote_url,
 108                                 const char *url,
 109                                 const char *up_path)
 110 {
 111         int is_relative = 0;
 112         int colonsep = 0;
 113         char *out;
 114         char *remoteurl = xstrdup(remote_url);
 115         struct strbuf sb = STRBUF_INIT;
 116         size_t len = strlen(remoteurl);
 117
 118         if (is_dir_sep(remoteurl[len-1]))
 119                 remoteurl[len-1] = '\0';
 120
 121         if (!url_is_local_not_ssh(remoteurl) || is_absolute_path(remoteurl))
 122                 is_relative = 0;
 123         else {
 124                 is_relative = 1;
 125                 /*
 126                  * Prepend a './' to ensure all relative
 127                  * remoteurls start with './' or '../'
 128                  */
 129                 if (!starts_with_dot_slash(remoteurl) &&
 130                     !starts_with_dot_dot_slash(remoteurl)) {
 131                         strbuf_reset(&sb);
 132                         strbuf_addf(&sb, "./%s", remoteurl);
 133                         free(remoteurl);
 134                         remoteurl = strbuf_detach(&sb, NULL);
 135                 }
 136         }
 137         /*
 138          * When the url starts with '../', remove that and the
 139          * last directory in remoteurl.
 140          */
 141         while (url) {
 142                 if (starts_with_dot_dot_slash(url)) {
 143                         url += 3;
 144                         colonsep |= chop_last_dir(&remoteurl, is_relative);
 145                 } else if (starts_with_dot_slash(url))
 146                         url += 2;
 147                 else
 148                         break;
 149         }
 150         strbuf_reset(&sb);
 151         strbuf_addf(&sb, "%s%s%s", remoteurl, colonsep ? ":" : "/", url);
 152         if (ends_with(url, "/"))
 153                 strbuf_setlen(&sb, sb.len - 1);
 154         free(remoteurl);
 155
 156         if (starts_with_dot_slash(sb.buf))
 157                 out = xstrdup(sb.buf + 2);
 158         else
 159                 out = xstrdup(sb.buf);
 160         strbuf_reset(&sb);
 161
 162         if (!up_path || !is_relative)
 163                 return out;
 164
 165         strbuf_addf(&sb, "%s%s", up_path, out);
 166         free(out);
 167         return strbuf_detach(&sb, NULL);
 168 }
 169
 170 static int resolve_relative_url(int argc, const char **argv, const char *prefix)
 171 {
 172         char *remoteurl = NULL;
 173         char *remote = get_default_remote();
 174         const char *up_path = NULL;
 175         char *res;
 176         const char *url;
 177         struct strbuf sb = STRBUF_INIT;
 178
 179         if (argc != 2 && argc != 3)
 180                 die("resolve-relative-url only accepts one or two arguments");
 181
 182         url = argv[1];
 183         strbuf_addf(&sb, "remote.%s.url", remote);
 184         free(remote);
 185
 186         if (git_config_get_string(sb.buf, &remoteurl))
 187                 /* the repository is its own authoritative upstream */
 188                 remoteurl = xgetcwd();
 189
 190         if (argc == 3)
 191                 up_path = argv[2];
 192
 193         res = relative_url(remoteurl, url, up_path);
 194         puts(res);
 195         free(res);
 196         free(remoteurl);
 197         return 0;
 198 }
 199
 200 static int resolve_relative_url_test(int argc, const char **argv, const char *prefix)
 201 {
 202         char *remoteurl, *res;
 203         const char *up_path, *url;
 204
 205         if (argc != 4)
 206                 die("resolve-relative-url-test only accepts three arguments: <up_path> <remoteurl> <url>");
 207
 208         up_path = argv[1];
 209         remoteurl = xstrdup(argv[2]);
 210         url = argv[3];
 211
 212         if (!strcmp(up_path, "(null)"))
 213                 up_path = NULL;
 214
 215         res = relative_url(remoteurl, url, up_path);
 216         puts(res);
 217         free(res);
 218         free(remoteurl);
 219         return 0;
 220 }
 221
 222 struct module_list {
 223         const struct cache_entry **entries;
 224         int alloc, nr;
 225 };
 226 #define MODULE_LIST_INIT { NULL, 0, 0 }
 227
 228 static int module_list_compute(int argc, const char **argv,
 229                                const char *prefix,
 230                                struct pathspec *pathspec,
 231                                struct module_list *list)
 232 {
 233         int i, result = 0;
 234         char *ps_matched = NULL;
 235         parse_pathspec(pathspec, 0,
 236                        PATHSPEC_PREFER_FULL |
 237                        PATHSPEC_STRIP_SUBMODULE_SLASH_CHEAP,
 238                        prefix, argv);
 239
 240         if (pathspec->nr)
 241                 ps_matched = xcalloc(pathspec->nr, 1);
 242
 243         if (read_cache() < 0)
 244                 die(_("index file corrupt"));
 245
 246         for (i = 0; i < active_nr; i++) {
 247                 const struct cache_entry *ce = active_cache[i];
 248
 249                 if (!match_pathspec(pathspec, ce->name, ce_namelen(ce),
 250                                     0, ps_matched, 1) ||
 251                     !S_ISGITLINK(ce->ce_mode))
 252                         continue;
 253
 254                 ALLOC_GROW(list->entries, list->nr + 1, list->alloc);
 255                 list->entries[list->nr++] = ce;
 256                 while (i + 1 < active_nr &&
 257                        !strcmp(ce->name, active_cache[i + 1]->name))
 258                         /*
 259                          * Skip entries with the same name in different stages
 260                          * to make sure an entry is returned only once.
 261                          */
 262                         i++;
 263         }
 264
 265         if (ps_matched && report_path_error(ps_matched, pathspec, prefix))
 266                 result = -1;
 267
 268         free(ps_matched);
 269
 270         return result;
 271 }
 272
 273 static int module_list(int argc, const char **argv, const char *prefix)
 274 {
 275         int i;
 276         struct pathspec pathspec;
 277         struct module_list list = MODULE_LIST_INIT;
 278
 279         struct option module_list_options[] = {
 280                 OPT_STRING(0, "prefix", &prefix,
 281                            N_("path"),
 282                            N_("alternative anchor for relative paths")),
 283                 OPT_END()
 284         };
 285
 286         const char *const git_submodule_helper_usage[] = {
 287                 N_("git submodule--helper list [--prefix=<path>] [<path>...]"),
 288                 NULL
 289         };
 290
 291         argc = parse_options(argc, argv, prefix, module_list_options,
 292                              git_submodule_helper_usage, 0);
 293
 294         if (module_list_compute(argc, argv, prefix, &pathspec, &list) < 0)
 295                 return 1;
 296
 297         for (i = 0; i < list.nr; i++) {
 298                 const struct cache_entry *ce = list.entries[i];
 299
 300                 if (ce_stage(ce))
 301                         printf("%06o %s U\t", ce->ce_mode, sha1_to_hex(null_sha1));
 302                 else
 303                         printf("%06o %s %d\t", ce->ce_mode,
 304                                oid_to_hex(&ce->oid), ce_stage(ce));
 305
 306                 utf8_fprintf(stdout, "%s\n", ce->name);
 307         }
 308         return 0;
 309 }
 310
 311 static void init_submodule(const char *path, const char *prefix, int quiet)
 312 {
 313         const struct submodule *sub;
 314         struct strbuf sb = STRBUF_INIT;
 315         char *upd = NULL, *url = NULL, *displaypath;
 316
 317         /* Only loads from .gitmodules, no overlay with .git/config */
 318         gitmodules_config();
 319
 320         if (prefix && get_super_prefix())
 321                 die("BUG: cannot have prefix and superprefix");
 322         else if (prefix)
 323                 displaypath = xstrdup(relative_path(path, prefix, &sb));
 324         else if (get_super_prefix()) {
 325                 strbuf_addf(&sb, "%s%s", get_super_prefix(), path);
 326                 displaypath = strbuf_detach(&sb, NULL);
 327         } else
 328                 displaypath = xstrdup(path);
 329
 330         sub = submodule_from_path(null_sha1, path);
 331
 332         if (!sub)
 333                 die(_("No url found for submodule path '%s' in .gitmodules"),
 334                         displaypath);
 335
 336         /*
 337          * Copy url setting when it is not set yet.
 338          * To look up the url in .git/config, we must not fall back to
 339          * .gitmodules, so look it up directly.
 340          */
 341         strbuf_reset(&sb);
 342         strbuf_addf(&sb, "submodule.%s.url", sub->name);
 343         if (git_config_get_string(sb.buf, &url)) {
 344                 url = xstrdup(sub->url);
 345
 346                 if (!url)
 347                         die(_("No url found for submodule path '%s' in .gitmodules"),
 348                                 displaypath);
 349
 350                 /* Possibly a url relative to parent */
 351                 if (starts_with_dot_dot_slash(url) ||
 352                     starts_with_dot_slash(url)) {
 353                         char *remoteurl, *relurl;
 354                         char *remote = get_default_remote();
 355                         struct strbuf remotesb = STRBUF_INIT;
 356                         strbuf_addf(&remotesb, "remote.%s.url", remote);
 357                         free(remote);
 358
 359                         if (git_config_get_string(remotesb.buf, &remoteurl))
 360                                 /*
 361                                  * The repository is its own
 362                                  * authoritative upstream
 363                                  */
 364                                 remoteurl = xgetcwd();
 365                         relurl = relative_url(remoteurl, url, NULL);
 366                         strbuf_release(&remotesb);
 367                         free(remoteurl);
 368                         free(url);
 369                         url = relurl;
 370                 }
 371
 372                 if (git_config_set_gently(sb.buf, url))
 373                         die(_("Failed to register url for submodule path '%s'"),
 374                             displaypath);
 375                 if (!quiet)
 376                         fprintf(stderr,
 377                                 _("Submodule '%s' (%s) registered for path '%s'\n"),
 378                                 sub->name, url, displaypath);
 379         }
 380
 381         /* Copy "update" setting when it is not set yet */
 382         strbuf_reset(&sb);
 383         strbuf_addf(&sb, "submodule.%s.update", sub->name);
 384         if (git_config_get_string(sb.buf, &upd) &&
 385             sub->update_strategy.type != SM_UPDATE_UNSPECIFIED) {
 386                 if (sub->update_strategy.type == SM_UPDATE_COMMAND) {
 387                         fprintf(stderr, _("warning: command update mode suggested for submodule '%s'\n"),
 388                                 sub->name);
 389                         upd = xstrdup("none");
 390                 } else
 391                         upd = xstrdup(submodule_strategy_to_string(&sub->update_strategy));
 392
 393                 if (git_config_set_gently(sb.buf, upd))
 394                         die(_("Failed to register update mode for submodule path '%s'"), displaypath);
 395         }
 396         strbuf_release(&sb);
 397         free(displaypath);
 398         free(url);
 399         free(upd);
 400 }
 401
 402 static int module_init(int argc, const char **argv, const char *prefix)
 403 {
 404         struct pathspec pathspec;
 405         struct module_list list = MODULE_LIST_INIT;
 406         int quiet = 0;
 407         int i;
 408
 409         struct option module_init_options[] = {
 410                 OPT__QUIET(&quiet, N_("Suppress output for initializing a submodule")),
 411                 OPT_END()
 412         };
 413
 414         const char *const git_submodule_helper_usage[] = {
 415                 N_("git submodule--helper init [<path>]"),
 416                 NULL
 417         };
 418
 419         argc = parse_options(argc, argv, prefix, module_init_options,
 420                              git_submodule_helper_usage, 0);
 421
 422         if (module_list_compute(argc, argv, prefix, &pathspec, &list) < 0)
 423                 return 1;
 424
 425         for (i = 0; i < list.nr; i++)
 426                 init_submodule(list.entries[i]->name, prefix, quiet);
 427
 428         return 0;
 429 }
 430
 431 static int module_name(int argc, const char **argv, const char *prefix)
 432 {
 433         const struct submodule *sub;
 434
 435         if (argc != 2)
 436                 usage(_("git submodule--helper name <path>"));
 437
 438         gitmodules_config();
 439         sub = submodule_from_path(null_sha1, argv[1]);
 440
 441         if (!sub)
 442                 die(_("no submodule mapping found in .gitmodules for path '%s'"),
 443                     argv[1]);
 444
 445         printf("%s\n", sub->name);
 446
 447         return 0;
 448 }
 449
 450 static int clone_submodule(const char *path, const char *gitdir, const char *url,
 451                            const char *depth, struct string_list *reference,
 452                            int quiet, int progress)
 453 {
 454         struct child_process cp = CHILD_PROCESS_INIT;
 455
 456         argv_array_push(&cp.args, "clone");
 457         argv_array_push(&cp.args, "--no-checkout");
 458         if (quiet)
 459                 argv_array_push(&cp.args, "--quiet");
 460         if (progress)
 461                 argv_array_push(&cp.args, "--progress");
 462         if (depth && *depth)
 463                 argv_array_pushl(&cp.args, "--depth", depth, NULL);
 464         if (reference->nr) {
 465                 struct string_list_item *item;
 466                 for_each_string_list_item(item, reference)
 467                         argv_array_pushl(&cp.args, "--reference",
 468                                          item->string, NULL);
 469         }
 470         if (gitdir && *gitdir)
 471                 argv_array_pushl(&cp.args, "--separate-git-dir", gitdir, NULL);
 472
 473         argv_array_push(&cp.args, url);
 474         argv_array_push(&cp.args, path);
 475
 476         cp.git_cmd = 1;
 477         prepare_submodule_repo_env(&cp.env_array);
 478         cp.no_stdin = 1;
 479
 480         return run_command(&cp);
 481 }
 482
 483 struct submodule_alternate_setup {
 484         const char *submodule_name;
 485         enum SUBMODULE_ALTERNATE_ERROR_MODE {
 486                 SUBMODULE_ALTERNATE_ERROR_DIE,
 487                 SUBMODULE_ALTERNATE_ERROR_INFO,
 488                 SUBMODULE_ALTERNATE_ERROR_IGNORE
 489         } error_mode;
 490         struct string_list *reference;
 491 };
 492 #define SUBMODULE_ALTERNATE_SETUP_INIT { NULL, \
 493         SUBMODULE_ALTERNATE_ERROR_IGNORE, NULL }
 494
 495 static int add_possible_reference_from_superproject(
 496                 struct alternate_object_database *alt, void *sas_cb)
 497 {
 498         struct submodule_alternate_setup *sas = sas_cb;
 499
 500         /*
 501          * If the alternate object store is another repository, try the
 502          * standard layout with .git/(modules/<name>)+/objects
 503          */
 504         if (ends_with(alt->path, "/objects")) {
 505                 char *sm_alternate;
 506                 struct strbuf sb = STRBUF_INIT;
 507                 struct strbuf err = STRBUF_INIT;
 508                 strbuf_add(&sb, alt->path, strlen(alt->path) - strlen("objects"));
 509
 510                 /*
 511                  * We need to end the new path with '/' to mark it as a dir,
 512                  * otherwise a submodule name containing '/' will be broken
 513                  * as the last part of a missing submodule reference would
 514                  * be taken as a file name.
 515                  */
 516                 strbuf_addf(&sb, "modules/%s/", sas->submodule_name);
 517
 518                 sm_alternate = compute_alternate_path(sb.buf, &err);
 519                 if (sm_alternate) {
 520                         string_list_append(sas->reference, xstrdup(sb.buf));
 521                         free(sm_alternate);
 522                 } else {
 523                         switch (sas->error_mode) {
 524                         case SUBMODULE_ALTERNATE_ERROR_DIE:
 525                                 die(_("submodule '%s' cannot add alternate: %s"),
 526                                     sas->submodule_name, err.buf);
 527                         case SUBMODULE_ALTERNATE_ERROR_INFO:
 528                                 fprintf(stderr, _("submodule '%s' cannot add alternate: %s"),
 529                                         sas->submodule_name, err.buf);
 530                         case SUBMODULE_ALTERNATE_ERROR_IGNORE:
 531                                 ; /* nothing */
 532                         }
 533                 }
 534                 strbuf_release(&sb);
 535         }
 536
 537         return 0;
 538 }
 539
 540 static void prepare_possible_alternates(const char *sm_name,
 541                 struct string_list *reference)
 542 {
 543         char *sm_alternate = NULL, *error_strategy = NULL;
 544         struct submodule_alternate_setup sas = SUBMODULE_ALTERNATE_SETUP_INIT;
 545
 546         git_config_get_string("submodule.alternateLocation", &sm_alternate);
 547         if (!sm_alternate)
 548                 return;
 549
 550         git_config_get_string("submodule.alternateErrorStrategy", &error_strategy);
 551
 552         if (!error_strategy)
 553                 error_strategy = xstrdup("die");
 554
 555         sas.submodule_name = sm_name;
 556         sas.reference = reference;
 557         if (!strcmp(error_strategy, "die"))
 558                 sas.error_mode = SUBMODULE_ALTERNATE_ERROR_DIE;
 559         else if (!strcmp(error_strategy, "info"))
 560                 sas.error_mode = SUBMODULE_ALTERNATE_ERROR_INFO;
 561         else if (!strcmp(error_strategy, "ignore"))
 562                 sas.error_mode = SUBMODULE_ALTERNATE_ERROR_IGNORE;
 563         else
 564                 die(_("Value '%s' for submodule.alternateErrorStrategy is not recognized"), error_strategy);
 565
 566         if (!strcmp(sm_alternate, "superproject"))
 567                 foreach_alt_odb(add_possible_reference_from_superproject, &sas);
 568         else if (!strcmp(sm_alternate, "no"))
 569                 ; /* do nothing */
 570         else
 571                 die(_("Value '%s' for submodule.alternateLocation is not recognized"), sm_alternate);
 572
 573         free(sm_alternate);
 574         free(error_strategy);
 575 }
 576
 577 static int module_clone(int argc, const char **argv, const char *prefix)
 578 {
 579         const char *name = NULL, *url = NULL, *depth = NULL;
 580         int quiet = 0;
 581         int progress = 0;
 582         FILE *submodule_dot_git;
 583         char *p, *path = NULL, *sm_gitdir;
 584         struct strbuf rel_path = STRBUF_INIT;
 585         struct strbuf sb = STRBUF_INIT;
 586         struct string_list reference = STRING_LIST_INIT_NODUP;
 587         char *sm_alternate = NULL, *error_strategy = NULL;
 588
 589         struct option module_clone_options[] = {
 590                 OPT_STRING(0, "prefix", &prefix,
 591                            N_("path"),
 592                            N_("alternative anchor for relative paths")),
 593                 OPT_STRING(0, "path", &path,
 594                            N_("path"),
 595                            N_("where the new submodule will be cloned to")),
 596                 OPT_STRING(0, "name", &name,
 597                            N_("string"),
 598                            N_("name of the new submodule")),
 599                 OPT_STRING(0, "url", &url,
 600                            N_("string"),
 601                            N_("url where to clone the submodule from")),
 602                 OPT_STRING_LIST(0, "reference", &reference,
 603                            N_("repo"),
 604                            N_("reference repository")),
 605                 OPT_STRING(0, "depth", &depth,
 606                            N_("string"),
 607                            N_("depth for shallow clones")),
 608                 OPT__QUIET(&quiet, "Suppress output for cloning a submodule"),
 609                 OPT_BOOL(0, "progress", &progress,
 610                            N_("force cloning progress")),
 611                 OPT_END()
 612         };
 613
 614         const char *const git_submodule_helper_usage[] = {
 615                 N_("git submodule--helper clone [--prefix=<path>] [--quiet] "
 616                    "[--reference <repository>] [--name <name>] [--depth <depth>] "
 617                    "--url <url> --path <path>"),
 618                 NULL
 619         };
 620
 621         argc = parse_options(argc, argv, prefix, module_clone_options,
 622                              git_submodule_helper_usage, 0);
 623
 624         if (argc || !url || !path || !*path)
 625                 usage_with_options(git_submodule_helper_usage,
 626                                    module_clone_options);
 627
 628         strbuf_addf(&sb, "%s/modules/%s", get_git_dir(), name);
 629         sm_gitdir = absolute_pathdup(sb.buf);
 630         strbuf_reset(&sb);
 631
 632         if (!is_absolute_path(path)) {
 633                 strbuf_addf(&sb, "%s/%s", get_git_work_tree(), path);
 634                 path = strbuf_detach(&sb, NULL);
 635         } else
 636                 path = xstrdup(path);
 637
 638         if (!file_exists(sm_gitdir)) {
 639                 if (safe_create_leading_directories_const(sm_gitdir) < 0)
 640                         die(_("could not create directory '%s'"), sm_gitdir);
 641
 642                 prepare_possible_alternates(name, &reference);
 643
 644                 if (clone_submodule(path, sm_gitdir, url, depth, &reference,
 645                                     quiet, progress))
 646                         die(_("clone of '%s' into submodule path '%s' failed"),
 647                             url, path);
 648         } else {
 649                 if (safe_create_leading_directories_const(path) < 0)
 650                         die(_("could not create directory '%s'"), path);
 651                 strbuf_addf(&sb, "%s/index", sm_gitdir);
 652                 unlink_or_warn(sb.buf);
 653                 strbuf_reset(&sb);
 654         }
 655
 656         /* Write a .git file in the submodule to redirect to the superproject. */
 657         strbuf_addf(&sb, "%s/.git", path);
 658         if (safe_create_leading_directories_const(sb.buf) < 0)
 659                 die(_("could not create leading directories of '%s'"), sb.buf);
 660         submodule_dot_git = fopen(sb.buf, "w");
 661         if (!submodule_dot_git)
 662                 die_errno(_("cannot open file '%s'"), sb.buf);
 663
 664         fprintf_or_die(submodule_dot_git, "gitdir: %s\n",
 665                        relative_path(sm_gitdir, path, &rel_path));
 666         if (fclose(submodule_dot_git))
 667                 die(_("could not close file %s"), sb.buf);
 668         strbuf_reset(&sb);
 669         strbuf_reset(&rel_path);
 670
 671         /* Redirect the worktree of the submodule in the superproject's config */
 672         p = git_pathdup_submodule(path, "config");
 673         if (!p)
 674                 die(_("could not get submodule directory for '%s'"), path);
 675         git_config_set_in_file(p, "core.worktree",
 676                                relative_path(path, sm_gitdir, &rel_path));
 677
 678         /* setup alternateLocation and alternateErrorStrategy in the cloned submodule if needed */
 679         git_config_get_string("submodule.alternateLocation", &sm_alternate);
 680         if (sm_alternate)
 681                 git_config_set_in_file(p, "submodule.alternateLocation",
 682                                            sm_alternate);
 683         git_config_get_string("submodule.alternateErrorStrategy", &error_strategy);
 684         if (error_strategy)
 685                 git_config_set_in_file(p, "submodule.alternateErrorStrategy",
 686                                            error_strategy);
 687
 688         free(sm_alternate);
 689         free(error_strategy);
 690
 691         strbuf_release(&sb);
 692         strbuf_release(&rel_path);
 693         free(sm_gitdir);
 694         free(path);
 695         free(p);
 696         return 0;
 697 }
 698
 699 struct submodule_update_clone {
 700         /* index into 'list', the list of submodules to look into for cloning */
 701         int current;
 702         struct module_list list;
 703         unsigned warn_if_uninitialized : 1;
 704
 705         /* update parameter passed via commandline */
 706         struct submodule_update_strategy update;
 707
 708         /* configuration parameters which are passed on to the children */
 709         int progress;
 710         int quiet;
 711         int recommend_shallow;
 712         struct string_list references;
 713         const char *depth;
 714         const char *recursive_prefix;
 715         const char *prefix;
 716
 717         /* Machine-readable status lines to be consumed by git-submodule.sh */
 718         struct string_list projectlines;
 719
 720         /* If we want to stop as fast as possible and return an error */
 721         unsigned quickstop : 1;
 722
 723         /* failed clones to be retried again */
 724         const struct cache_entry **failed_clones;
 725         int failed_clones_nr, failed_clones_alloc;
 726 };
 727 #define SUBMODULE_UPDATE_CLONE_INIT {0, MODULE_LIST_INIT, 0, \
 728         SUBMODULE_UPDATE_STRATEGY_INIT, 0, 0, -1, STRING_LIST_INIT_DUP, \
 729         NULL, NULL, NULL, \
 730         STRING_LIST_INIT_DUP, 0, NULL, 0, 0}
 731
 732
 733 static void next_submodule_warn_missing(struct submodule_update_clone *suc,
 734                 struct strbuf *out, const char *displaypath)
 735 {
 736         /*
 737          * Only mention uninitialized submodules when their
 738          * paths have been specified.
 739          */
 740         if (suc->warn_if_uninitialized) {
 741                 strbuf_addf(out,
 742                         _("Submodule path '%s' not initialized"),
 743                         displaypath);
 744                 strbuf_addch(out, '\n');
 745                 strbuf_addstr(out,
 746                         _("Maybe you want to use 'update --init'?"));
 747                 strbuf_addch(out, '\n');
 748         }
 749 }
 750
 751 /**
 752  * Determine whether 'ce' needs to be cloned. If so, prepare the 'child' to
 753  * run the clone. Returns 1 if 'ce' needs to be cloned, 0 otherwise.
 754  */
 755 static int prepare_to_clone_next_submodule(const struct cache_entry *ce,
 756                                            struct child_process *child,
 757                                            struct submodule_update_clone *suc,
 758                                            struct strbuf *out)
 759 {
 760         const struct submodule *sub = NULL;
 761         struct strbuf displaypath_sb = STRBUF_INIT;
 762         struct strbuf sb = STRBUF_INIT;
 763         const char *displaypath = NULL;
 764         char *url = NULL;
 765         int needs_cloning = 0;
 766
 767         if (ce_stage(ce)) {
 768                 if (suc->recursive_prefix)
 769                         strbuf_addf(&sb, "%s/%s", suc->recursive_prefix, ce->name);
 770                 else
 771                         strbuf_addstr(&sb, ce->name);
 772                 strbuf_addf(out, _("Skipping unmerged submodule %s"), sb.buf);
 773                 strbuf_addch(out, '\n');
 774                 goto cleanup;
 775         }
 776
 777         sub = submodule_from_path(null_sha1, ce->name);
 778
 779         if (suc->recursive_prefix)
 780                 displaypath = relative_path(suc->recursive_prefix,
 781                                             ce->name, &displaypath_sb);
 782         else
 783                 displaypath = ce->name;
 784
 785         if (!sub) {
 786                 next_submodule_warn_missing(suc, out, displaypath);
 787                 goto cleanup;
 788         }
 789
 790         if (suc->update.type == SM_UPDATE_NONE
 791             || (suc->update.type == SM_UPDATE_UNSPECIFIED
 792                 && sub->update_strategy.type == SM_UPDATE_NONE)) {
 793                 strbuf_addf(out, _("Skipping submodule '%s'"), displaypath);
 794                 strbuf_addch(out, '\n');
 795                 goto cleanup;
 796         }
 797
 798         /*
 799          * Looking up the url in .git/config.
 800          * We must not fall back to .gitmodules as we only want
 801          * to process configured submodules.
 802          */
 803         strbuf_reset(&sb);
 804         strbuf_addf(&sb, "submodule.%s.url", sub->name);
 805         git_config_get_string(sb.buf, &url);
 806         if (!url) {
 807                 next_submodule_warn_missing(suc, out, displaypath);
 808                 goto cleanup;
 809         }
 810
 811         strbuf_reset(&sb);
 812         strbuf_addf(&sb, "%s/.git", ce->name);
 813         needs_cloning = !file_exists(sb.buf);
 814
 815         strbuf_reset(&sb);
 816         strbuf_addf(&sb, "%06o %s %d %d\t%s\n", ce->ce_mode,
 817                         oid_to_hex(&ce->oid), ce_stage(ce),
 818                         needs_cloning, ce->name);
 819         string_list_append(&suc->projectlines, sb.buf);
 820
 821         if (!needs_cloning)
 822                 goto cleanup;
 823
 824         child->git_cmd = 1;
 825         child->no_stdin = 1;
 826         child->stdout_to_stderr = 1;
 827         child->err = -1;
 828         argv_array_push(&child->args, "submodule--helper");
 829         argv_array_push(&child->args, "clone");
 830         if (suc->progress)
 831                 argv_array_push(&child->args, "--progress");
 832         if (suc->quiet)
 833                 argv_array_push(&child->args, "--quiet");
 834         if (suc->prefix)
 835                 argv_array_pushl(&child->args, "--prefix", suc->prefix, NULL);
 836         if (suc->recommend_shallow && sub->recommend_shallow == 1)
 837                 argv_array_push(&child->args, "--depth=1");
 838         argv_array_pushl(&child->args, "--path", sub->path, NULL);
 839         argv_array_pushl(&child->args, "--name", sub->name, NULL);
 840         argv_array_pushl(&child->args, "--url", url, NULL);
 841         if (suc->references.nr) {
 842                 struct string_list_item *item;
 843                 for_each_string_list_item(item, &suc->references)
 844                         argv_array_pushl(&child->args, "--reference", item->string, NULL);
 845         }
 846         if (suc->depth)
 847                 argv_array_push(&child->args, suc->depth);
 848
 849 cleanup:
 850         free(url);
 851         strbuf_reset(&displaypath_sb);
 852         strbuf_reset(&sb);
 853
 854         return needs_cloning;
 855 }
 856
 857 static int update_clone_get_next_task(struct child_process *child,
 858                                       struct strbuf *err,
 859                                       void *suc_cb,
 860                                       void **idx_task_cb)
 861 {
 862         struct submodule_update_clone *suc = suc_cb;
 863         const struct cache_entry *ce;
 864         int index;
 865
 866         for (; suc->current < suc->list.nr; suc->current++) {
 867                 ce = suc->list.entries[suc->current];
 868                 if (prepare_to_clone_next_submodule(ce, child, suc, err)) {
 869                         int *p = xmalloc(sizeof(*p));
 870                         *p = suc->current;
 871                         *idx_task_cb = p;
 872                         suc->current++;
 873                         return 1;
 874                 }
 875         }
 876
 877         /*
 878          * The loop above tried cloning each submodule once, now try the
 879          * stragglers again, which we can imagine as an extension of the
 880          * entry list.
 881          */
 882         index = suc->current - suc->list.nr;
 883         if (index < suc->failed_clones_nr) {
 884                 int *p;
 885                 ce = suc->failed_clones[index];
 886                 if (!prepare_to_clone_next_submodule(ce, child, suc, err)) {
 887                         suc->current ++;
 888                         strbuf_addstr(err, "BUG: submodule considered for "
 889                                            "cloning, doesn't need cloning "
 890                                            "any more?\n");
 891                         return 0;
 892                 }
 893                 p = xmalloc(sizeof(*p));
 894                 *p = suc->current;
 895                 *idx_task_cb = p;
 896                 suc->current ++;
 897                 return 1;
 898         }
 899
 900         return 0;
 901 }
 902
 903 static int update_clone_start_failure(struct strbuf *err,
 904                                       void *suc_cb,
 905                                       void *idx_task_cb)
 906 {
 907         struct submodule_update_clone *suc = suc_cb;
 908         suc->quickstop = 1;
 909         return 1;
 910 }
 911
 912 static int update_clone_task_finished(int result,
 913                                       struct strbuf *err,
 914                                       void *suc_cb,
 915                                       void *idx_task_cb)
 916 {
 917         const struct cache_entry *ce;
 918         struct submodule_update_clone *suc = suc_cb;
 919
 920         int *idxP = *(int**)idx_task_cb;
 921         int idx = *idxP;
 922         free(idxP);
 923
 924         if (!result)
 925                 return 0;
 926
 927         if (idx < suc->list.nr) {
 928                 ce  = suc->list.entries[idx];
 929                 strbuf_addf(err, _("Failed to clone '%s'. Retry scheduled"),
 930                             ce->name);
 931                 strbuf_addch(err, '\n');
 932                 ALLOC_GROW(suc->failed_clones,
 933                            suc->failed_clones_nr + 1,
 934                            suc->failed_clones_alloc);
 935                 suc->failed_clones[suc->failed_clones_nr++] = ce;
 936                 return 0;
 937         } else {
 938                 idx -= suc->list.nr;
 939                 ce  = suc->failed_clones[idx];
 940                 strbuf_addf(err, _("Failed to clone '%s' a second time, aborting"),
 941                             ce->name);
 942                 strbuf_addch(err, '\n');
 943                 suc->quickstop = 1;
 944                 return 1;
 945         }
 946
 947         return 0;
 948 }
 949
 950 static int update_clone(int argc, const char **argv, const char *prefix)
 951 {
 952         const char *update = NULL;
 953         int max_jobs = -1;
 954         struct string_list_item *item;
 955         struct pathspec pathspec;
 956         struct submodule_update_clone suc = SUBMODULE_UPDATE_CLONE_INIT;
 957
 958         struct option module_update_clone_options[] = {
 959                 OPT_STRING(0, "prefix", &prefix,
 960                            N_("path"),
 961                            N_("path into the working tree")),
 962                 OPT_STRING(0, "recursive-prefix", &suc.recursive_prefix,
 963                            N_("path"),
 964                            N_("path into the working tree, across nested "
 965                               "submodule boundaries")),
 966                 OPT_STRING(0, "update", &update,
 967                            N_("string"),
 968                            N_("rebase, merge, checkout or none")),
 969                 OPT_STRING_LIST(0, "reference", &suc.references, N_("repo"),
 970                            N_("reference repository")),
 971                 OPT_STRING(0, "depth", &suc.depth, "<depth>",
 972                            N_("Create a shallow clone truncated to the "
 973                               "specified number of revisions")),
 974                 OPT_INTEGER('j', "jobs", &max_jobs,
 975                             N_("parallel jobs")),
 976                 OPT_BOOL(0, "recommend-shallow", &suc.recommend_shallow,
 977                             N_("whether the initial clone should follow the shallow recommendation")),
 978                 OPT__QUIET(&suc.quiet, N_("don't print cloning progress")),
 979                 OPT_BOOL(0, "progress", &suc.progress,
 980                             N_("force cloning progress")),
 981                 OPT_END()
 982         };
 983
 984         const char *const git_submodule_helper_usage[] = {
 985                 N_("git submodule--helper update_clone [--prefix=<path>] [<path>...]"),
 986                 NULL
 987         };
 988         suc.prefix = prefix;
 989
 990         argc = parse_options(argc, argv, prefix, module_update_clone_options,
 991                              git_submodule_helper_usage, 0);
 992
 993         if (update)
 994                 if (parse_submodule_update_strategy(update, &suc.update) < 0)
 995                         die(_("bad value for update parameter"));
 996
 997         if (module_list_compute(argc, argv, prefix, &pathspec, &suc.list) < 0)
 998                 return 1;
 999
1000         if (pathspec.nr)
1001                 suc.warn_if_uninitialized = 1;
1002
1003         /* Overlay the parsed .gitmodules file with .git/config */
1004         gitmodules_config();
1005         git_config(submodule_config, NULL);
1006
1007         if (max_jobs < 0)
1008                 max_jobs = parallel_submodules();
1009
1010         run_processes_parallel(max_jobs,
1011                                update_clone_get_next_task,
1012                                update_clone_start_failure,
1013                                update_clone_task_finished,
1014                                &suc);
1015
1016         /*
1017          * We saved the output and put it out all at once now.
1018          * That means:
1019          * - the listener does not have to interleave their (checkout)
1020          *   work with our fetching.  The writes involved in a
1021          *   checkout involve more straightforward sequential I/O.
1022          * - the listener can avoid doing any work if fetching failed.
1023          */
1024         if (suc.quickstop)
1025                 return 1;
1026
1027         for_each_string_list_item(item, &suc.projectlines)
1028                 utf8_fprintf(stdout, "%s", item->string);
1029
1030         return 0;
1031 }
1032
1033 static int resolve_relative_path(int argc, const char **argv, const char *prefix)
1034 {
1035         struct strbuf sb = STRBUF_INIT;
1036         if (argc != 3)
1037                 die("submodule--helper relative-path takes exactly 2 arguments, got %d", argc);
1038
1039         printf("%s", relative_path(argv[1], argv[2], &sb));
1040         strbuf_release(&sb);
1041         return 0;
1042 }
1043
1044 static const char *remote_submodule_branch(const char *path)
1045 {
1046         const struct submodule *sub;
1047         gitmodules_config();
1048         git_config(submodule_config, NULL);
1049
1050         sub = submodule_from_path(null_sha1, path);
1051         if (!sub)
1052                 return NULL;
1053
1054         if (!sub->branch)
1055                 return "master";
1056
1057         if (!strcmp(sub->branch, ".")) {
1058                 unsigned char sha1[20];
1059                 const char *refname = resolve_ref_unsafe("HEAD", 0, sha1, NULL);
1060
1061                 if (!refname)
1062                         die(_("No such ref: %s"), "HEAD");
1063
1064                 /* detached HEAD */
1065                 if (!strcmp(refname, "HEAD"))
1066                         die(_("Submodule (%s) branch configured to inherit "
1067                               "branch from superproject, but the superproject "
1068                               "is not on any branch"), sub->name);
1069
1070                 if (!skip_prefix(refname, "refs/heads/", &refname))
1071                         die(_("Expecting a full ref name, got %s"), refname);
1072                 return refname;
1073         }
1074
1075         return sub->branch;
1076 }
1077
1078 static int resolve_remote_submodule_branch(int argc, const char **argv,
1079                 const char *prefix)
1080 {
1081         const char *ret;
1082         struct strbuf sb = STRBUF_INIT;
1083         if (argc != 2)
1084                 die("submodule--helper remote-branch takes exactly one arguments, got %d", argc);
1085
1086         ret = remote_submodule_branch(argv[1]);
1087         if (!ret)
1088                 die("submodule %s doesn't exist", argv[1]);
1089
1090         printf("%s", ret);
1091         strbuf_release(&sb);
1092         return 0;
1093 }
1094
1095 static int absorb_git_dirs(int argc, const char **argv, const char *prefix)
1096 {
1097         int i;
1098         struct pathspec pathspec;
1099         struct module_list list = MODULE_LIST_INIT;
1100         unsigned flags = ABSORB_GITDIR_RECURSE_SUBMODULES;
1101
1102         struct option embed_gitdir_options[] = {
1103                 OPT_STRING(0, "prefix", &prefix,
1104                            N_("path"),
1105                            N_("path into the working tree")),
1106                 OPT_BIT(0, "--recursive", &flags, N_("recurse into submodules"),
1107                         ABSORB_GITDIR_RECURSE_SUBMODULES),
1108                 OPT_END()
1109         };
1110
1111         const char *const git_submodule_helper_usage[] = {
1112                 N_("git submodule--helper embed-git-dir [<path>...]"),
1113                 NULL
1114         };
1115
1116         argc = parse_options(argc, argv, prefix, embed_gitdir_options,
1117                              git_submodule_helper_usage, 0);
1118
1119         gitmodules_config();
1120         git_config(submodule_config, NULL);
1121
1122         if (module_list_compute(argc, argv, prefix, &pathspec, &list) < 0)
1123                 return 1;
1124
1125         for (i = 0; i < list.nr; i++)
1126                 absorb_git_dir_into_superproject(prefix,
1127                                 list.entries[i]->name, flags);
1128
1129         return 0;
1130 }
1131
1132 #define SUPPORT_SUPER_PREFIX (1<<0)
1133
1134 struct cmd_struct {
1135         const char *cmd;
1136         int (*fn)(int, const char **, const char *);
1137         unsigned option;
1138 };
1139
1140 static struct cmd_struct commands[] = {
1141         {"list", module_list, 0},
1142         {"name", module_name, 0},
1143         {"clone", module_clone, 0},
1144         {"update-clone", update_clone, 0},
1145         {"relative-path", resolve_relative_path, 0},
1146         {"resolve-relative-url", resolve_relative_url, 0},
1147         {"resolve-relative-url-test", resolve_relative_url_test, 0},
1148         {"init", module_init, SUPPORT_SUPER_PREFIX},
1149         {"remote-branch", resolve_remote_submodule_branch, 0},
1150         {"absorb-git-dirs", absorb_git_dirs, SUPPORT_SUPER_PREFIX},
1151 };
1152
1153 int cmd_submodule__helper(int argc, const char **argv, const char *prefix)
1154 {
1155         int i;
1156         if (argc < 2)
1157                 die(_("submodule--helper subcommand must be "
1158                       "called with a subcommand"));
1159
1160         for (i = 0; i < ARRAY_SIZE(commands); i++) {
1161                 if (!strcmp(argv[1], commands[i].cmd)) {
1162                         if (get_super_prefix() &&
1163                             !(commands[i].option & SUPPORT_SUPER_PREFIX))
1164                                 die(_("%s doesn't support --super-prefix"),
1165                                     commands[i].cmd);
1166                         return commands[i].fn(argc - 1, argv + 1, prefix);
1167                 }
1168         }
1169
1170         die(_("'%s' is not a valid submodule--helper "
1171               "subcommand"), argv[1]);
1172 }