4cd3a6691a81b6689c9bcbdd96cd5e443a8904bb
   1/*
   2 * Builtin "git clone"
   3 *
   4 * Copyright (c) 2007 Kristian Høgsberg <krh@redhat.com>,
   5 *               2008 Daniel Barkalow <barkalow@iabervon.org>
   6 * Based on git-commit.sh by Junio C Hamano and Linus Torvalds
   7 *
   8 * Clone a repository into a different directory that does not yet exist.
   9 */
  10
  11#include "builtin.h"
  12#include "lockfile.h"
  13#include "parse-options.h"
  14#include "fetch-pack.h"
  15#include "refs.h"
  16#include "tree.h"
  17#include "tree-walk.h"
  18#include "unpack-trees.h"
  19#include "transport.h"
  20#include "strbuf.h"
  21#include "dir.h"
  22#include "sigchain.h"
  23#include "branch.h"
  24#include "remote.h"
  25#include "run-command.h"
  26#include "connected.h"
  27
  28/*
  29 * Overall FIXMEs:
  30 *  - respect DB_ENVIRONMENT for .git/objects.
  31 *
  32 * Implementation notes:
  33 *  - dropping use-separate-remote and no-separate-remote compatibility
  34 *
  35 */
  36static const char * const builtin_clone_usage[] = {
  37        N_("git clone [<options>] [--] <repo> [<dir>]"),
  38        NULL
  39};
  40
  41static int option_no_checkout, option_bare, option_mirror, option_single_branch = -1;
  42static int option_local = -1, option_no_hardlinks, option_shared, option_recursive;
  43static int option_shallow_submodules;
  44static char *option_template, *option_depth;
  45static char *option_origin = NULL;
  46static char *option_branch = NULL;
  47static const char *real_git_dir;
  48static char *option_upload_pack = "git-upload-pack";
  49static int option_verbosity;
  50static int option_progress = -1;
  51static enum transport_family family;
  52static struct string_list option_config = STRING_LIST_INIT_NODUP;
  53static struct string_list option_reference = STRING_LIST_INIT_NODUP;
  54static int option_dissociate;
  55static int max_jobs = -1;
  56
  57static struct option builtin_clone_options[] = {
  58        OPT__VERBOSITY(&option_verbosity),
  59        OPT_BOOL(0, "progress", &option_progress,
  60                 N_("force progress reporting")),
  61        OPT_BOOL('n', "no-checkout", &option_no_checkout,
  62                 N_("don't create a checkout")),
  63        OPT_BOOL(0, "bare", &option_bare, N_("create a bare repository")),
  64        OPT_HIDDEN_BOOL(0, "naked", &option_bare,
  65                        N_("create a bare repository")),
  66        OPT_BOOL(0, "mirror", &option_mirror,
  67                 N_("create a mirror repository (implies bare)")),
  68        OPT_BOOL('l', "local", &option_local,
  69                N_("to clone from a local repository")),
  70        OPT_BOOL(0, "no-hardlinks", &option_no_hardlinks,
  71                    N_("don't use local hardlinks, always copy")),
  72        OPT_BOOL('s', "shared", &option_shared,
  73                    N_("setup as shared repository")),
  74        OPT_BOOL(0, "recursive", &option_recursive,
  75                    N_("initialize submodules in the clone")),
  76        OPT_BOOL(0, "recurse-submodules", &option_recursive,
  77                    N_("initialize submodules in the clone")),
  78        OPT_INTEGER('j', "jobs", &max_jobs,
  79                    N_("number of submodules cloned in parallel")),
  80        OPT_STRING(0, "template", &option_template, N_("template-directory"),
  81                   N_("directory from which templates will be used")),
  82        OPT_STRING_LIST(0, "reference", &option_reference, N_("repo"),
  83                        N_("reference repository")),
  84        OPT_BOOL(0, "dissociate", &option_dissociate,
  85                 N_("use --reference only while cloning")),
  86        OPT_STRING('o', "origin", &option_origin, N_("name"),
  87                   N_("use <name> instead of 'origin' to track upstream")),
  88        OPT_STRING('b', "branch", &option_branch, N_("branch"),
  89                   N_("checkout <branch> instead of the remote's HEAD")),
  90        OPT_STRING('u', "upload-pack", &option_upload_pack, N_("path"),
  91                   N_("path to git-upload-pack on the remote")),
  92        OPT_STRING(0, "depth", &option_depth, N_("depth"),
  93                    N_("create a shallow clone of that depth")),
  94        OPT_BOOL(0, "single-branch", &option_single_branch,
  95                    N_("clone only one branch, HEAD or --branch")),
  96        OPT_BOOL(0, "shallow-submodules", &option_shallow_submodules,
  97                    N_("any cloned submodules will be shallow")),
  98        OPT_STRING(0, "separate-git-dir", &real_git_dir, N_("gitdir"),
  99                   N_("separate git dir from working tree")),
 100        OPT_STRING_LIST('c', "config", &option_config, N_("key=value"),
 101                        N_("set config inside the new repository")),
 102        OPT_SET_INT('4', "ipv4", &family, N_("use IPv4 addresses only"),
 103                        TRANSPORT_FAMILY_IPV4),
 104        OPT_SET_INT('6', "ipv6", &family, N_("use IPv6 addresses only"),
 105                        TRANSPORT_FAMILY_IPV6),
 106        OPT_END()
 107};
 108
 109static const char *get_repo_path_1(struct strbuf *path, int *is_bundle)
 110{
 111        static char *suffix[] = { "/.git", "", ".git/.git", ".git" };
 112        static char *bundle_suffix[] = { ".bundle", "" };
 113        size_t baselen = path->len;
 114        struct stat st;
 115        int i;
 116
 117        for (i = 0; i < ARRAY_SIZE(suffix); i++) {
 118                strbuf_setlen(path, baselen);
 119                strbuf_addstr(path, suffix[i]);
 120                if (stat(path->buf, &st))
 121                        continue;
 122                if (S_ISDIR(st.st_mode) && is_git_directory(path->buf)) {
 123                        *is_bundle = 0;
 124                        return path->buf;
 125                } else if (S_ISREG(st.st_mode) && st.st_size > 8) {
 126                        /* Is it a "gitfile"? */
 127                        char signature[8];
 128                        const char *dst;
 129                        int len, fd = open(path->buf, O_RDONLY);
 130                        if (fd < 0)
 131                                continue;
 132                        len = read_in_full(fd, signature, 8);
 133                        close(fd);
 134                        if (len != 8 || strncmp(signature, "gitdir: ", 8))
 135                                continue;
 136                        dst = read_gitfile(path->buf);
 137                        if (dst) {
 138                                *is_bundle = 0;
 139                                return dst;
 140                        }
 141                }
 142        }
 143
 144        for (i = 0; i < ARRAY_SIZE(bundle_suffix); i++) {
 145                strbuf_setlen(path, baselen);
 146                strbuf_addstr(path, bundle_suffix[i]);
 147                if (!stat(path->buf, &st) && S_ISREG(st.st_mode)) {
 148                        *is_bundle = 1;
 149                        return path->buf;
 150                }
 151        }
 152
 153        return NULL;
 154}
 155
 156static char *get_repo_path(const char *repo, int *is_bundle)
 157{
 158        struct strbuf path = STRBUF_INIT;
 159        const char *raw;
 160        char *canon;
 161
 162        strbuf_addstr(&path, repo);
 163        raw = get_repo_path_1(&path, is_bundle);
 164        canon = raw ? xstrdup(absolute_path(raw)) : NULL;
 165        strbuf_release(&path);
 166        return canon;
 167}
 168
 169static char *guess_dir_name(const char *repo, int is_bundle, int is_bare)
 170{
 171        const char *end = repo + strlen(repo), *start, *ptr;
 172        size_t len;
 173        char *dir;
 174
 175        /*
 176         * Skip scheme.
 177         */
 178        start = strstr(repo, "://");
 179        if (start == NULL)
 180                start = repo;
 181        else
 182                start += 3;
 183
 184        /*
 185         * Skip authentication data. The stripping does happen
 186         * greedily, such that we strip up to the last '@' inside
 187         * the host part.
 188         */
 189        for (ptr = start; ptr < end && !is_dir_sep(*ptr); ptr++) {
 190                if (*ptr == '@')
 191                        start = ptr + 1;
 192        }
 193
 194        /*
 195         * Strip trailing spaces, slashes and /.git
 196         */
 197        while (start < end && (is_dir_sep(end[-1]) || isspace(end[-1])))
 198                end--;
 199        if (end - start > 5 && is_dir_sep(end[-5]) &&
 200            !strncmp(end - 4, ".git", 4)) {
 201                end -= 5;
 202                while (start < end && is_dir_sep(end[-1]))
 203                        end--;
 204        }
 205
 206        /*
 207         * Strip trailing port number if we've got only a
 208         * hostname (that is, there is no dir separator but a
 209         * colon). This check is required such that we do not
 210         * strip URI's like '/foo/bar:2222.git', which should
 211         * result in a dir '2222' being guessed due to backwards
 212         * compatibility.
 213         */
 214        if (memchr(start, '/', end - start) == NULL
 215            && memchr(start, ':', end - start) != NULL) {
 216                ptr = end;
 217                while (start < ptr && isdigit(ptr[-1]) && ptr[-1] != ':')
 218                        ptr--;
 219                if (start < ptr && ptr[-1] == ':')
 220                        end = ptr - 1;
 221        }
 222
 223        /*
 224         * Find last component. To remain backwards compatible we
 225         * also regard colons as path separators, such that
 226         * cloning a repository 'foo:bar.git' would result in a
 227         * directory 'bar' being guessed.
 228         */
 229        ptr = end;
 230        while (start < ptr && !is_dir_sep(ptr[-1]) && ptr[-1] != ':')
 231                ptr--;
 232        start = ptr;
 233
 234        /*
 235         * Strip .{bundle,git}.
 236         */
 237        len = end - start;
 238        strip_suffix_mem(start, &len, is_bundle ? ".bundle" : ".git");
 239
 240        if (!len || (len == 1 && *start == '/'))
 241                die(_("No directory name could be guessed.\n"
 242                      "Please specify a directory on the command line"));
 243
 244        if (is_bare)
 245                dir = xstrfmt("%.*s.git", (int)len, start);
 246        else
 247                dir = xstrndup(start, len);
 248        /*
 249         * Replace sequences of 'control' characters and whitespace
 250         * with one ascii space, remove leading and trailing spaces.
 251         */
 252        if (*dir) {
 253                char *out = dir;
 254                int prev_space = 1 /* strip leading whitespace */;
 255                for (end = dir; *end; ++end) {
 256                        char ch = *end;
 257                        if ((unsigned char)ch < '\x20')
 258                                ch = '\x20';
 259                        if (isspace(ch)) {
 260                                if (prev_space)
 261                                        continue;
 262                                prev_space = 1;
 263                        } else
 264                                prev_space = 0;
 265                        *out++ = ch;
 266                }
 267                *out = '\0';
 268                if (out > dir && prev_space)
 269                        out[-1] = '\0';
 270        }
 271        return dir;
 272}
 273
 274static void strip_trailing_slashes(char *dir)
 275{
 276        char *end = dir + strlen(dir);
 277
 278        while (dir < end - 1 && is_dir_sep(end[-1]))
 279                end--;
 280        *end = '\0';
 281}
 282
 283static int add_one_reference(struct string_list_item *item, void *cb_data)
 284{
 285        struct strbuf err = STRBUF_INIT;
 286        struct strbuf sb = STRBUF_INIT;
 287        char *ref_git = compute_alternate_path(item->string, &err);
 288
 289        if (!ref_git)
 290                die("%s", err.buf);
 291
 292        strbuf_addf(&sb, "%s/objects", ref_git);
 293        add_to_alternates_file(sb.buf);
 294
 295        free(ref_git);
 296        strbuf_release(&err);
 297        strbuf_release(&sb);
 298        return 0;
 299}
 300
 301static void setup_reference(void)
 302{
 303        for_each_string_list(&option_reference, add_one_reference, NULL);
 304}
 305
 306static void copy_alternates(struct strbuf *src, struct strbuf *dst,
 307                            const char *src_repo)
 308{
 309        /*
 310         * Read from the source objects/info/alternates file
 311         * and copy the entries to corresponding file in the
 312         * destination repository with add_to_alternates_file().
 313         * Both src and dst have "$path/objects/info/alternates".
 314         *
 315         * Instead of copying bit-for-bit from the original,
 316         * we need to append to existing one so that the already
 317         * created entry via "clone -s" is not lost, and also
 318         * to turn entries with paths relative to the original
 319         * absolute, so that they can be used in the new repository.
 320         */
 321        FILE *in = fopen(src->buf, "r");
 322        struct strbuf line = STRBUF_INIT;
 323
 324        while (strbuf_getline(&line, in) != EOF) {
 325                char *abs_path;
 326                if (!line.len || line.buf[0] == '#')
 327                        continue;
 328                if (is_absolute_path(line.buf)) {
 329                        add_to_alternates_file(line.buf);
 330                        continue;
 331                }
 332                abs_path = mkpathdup("%s/objects/%s", src_repo, line.buf);
 333                normalize_path_copy(abs_path, abs_path);
 334                add_to_alternates_file(abs_path);
 335                free(abs_path);
 336        }
 337        strbuf_release(&line);
 338        fclose(in);
 339}
 340
 341static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
 342                                   const char *src_repo, int src_baselen)
 343{
 344        struct dirent *de;
 345        struct stat buf;
 346        int src_len, dest_len;
 347        DIR *dir;
 348
 349        dir = opendir(src->buf);
 350        if (!dir)
 351                die_errno(_("failed to open '%s'"), src->buf);
 352
 353        if (mkdir(dest->buf, 0777)) {
 354                if (errno != EEXIST)
 355                        die_errno(_("failed to create directory '%s'"), dest->buf);
 356                else if (stat(dest->buf, &buf))
 357                        die_errno(_("failed to stat '%s'"), dest->buf);
 358                else if (!S_ISDIR(buf.st_mode))
 359                        die(_("%s exists and is not a directory"), dest->buf);
 360        }
 361
 362        strbuf_addch(src, '/');
 363        src_len = src->len;
 364        strbuf_addch(dest, '/');
 365        dest_len = dest->len;
 366
 367        while ((de = readdir(dir)) != NULL) {
 368                strbuf_setlen(src, src_len);
 369                strbuf_addstr(src, de->d_name);
 370                strbuf_setlen(dest, dest_len);
 371                strbuf_addstr(dest, de->d_name);
 372                if (stat(src->buf, &buf)) {
 373                        warning (_("failed to stat %s\n"), src->buf);
 374                        continue;
 375                }
 376                if (S_ISDIR(buf.st_mode)) {
 377                        if (de->d_name[0] != '.')
 378                                copy_or_link_directory(src, dest,
 379                                                       src_repo, src_baselen);
 380                        continue;
 381                }
 382
 383                /* Files that cannot be copied bit-for-bit... */
 384                if (!strcmp(src->buf + src_baselen, "/info/alternates")) {
 385                        copy_alternates(src, dest, src_repo);
 386                        continue;
 387                }
 388
 389                if (unlink(dest->buf) && errno != ENOENT)
 390                        die_errno(_("failed to unlink '%s'"), dest->buf);
 391                if (!option_no_hardlinks) {
 392                        if (!link(src->buf, dest->buf))
 393                                continue;
 394                        if (option_local > 0)
 395                                die_errno(_("failed to create link '%s'"), dest->buf);
 396                        option_no_hardlinks = 1;
 397                }
 398                if (copy_file_with_time(dest->buf, src->buf, 0666))
 399                        die_errno(_("failed to copy file to '%s'"), dest->buf);
 400        }
 401        closedir(dir);
 402}
 403
 404static void clone_local(const char *src_repo, const char *dest_repo)
 405{
 406        if (option_shared) {
 407                struct strbuf alt = STRBUF_INIT;
 408                strbuf_addf(&alt, "%s/objects", src_repo);
 409                add_to_alternates_file(alt.buf);
 410                strbuf_release(&alt);
 411        } else {
 412                struct strbuf src = STRBUF_INIT;
 413                struct strbuf dest = STRBUF_INIT;
 414                get_common_dir(&src, src_repo);
 415                get_common_dir(&dest, dest_repo);
 416                strbuf_addstr(&src, "/objects");
 417                strbuf_addstr(&dest, "/objects");
 418                copy_or_link_directory(&src, &dest, src_repo, src.len);
 419                strbuf_release(&src);
 420                strbuf_release(&dest);
 421        }
 422
 423        if (0 <= option_verbosity)
 424                fprintf(stderr, _("done.\n"));
 425}
 426
 427static const char *junk_work_tree;
 428static const char *junk_git_dir;
 429static enum {
 430        JUNK_LEAVE_NONE,
 431        JUNK_LEAVE_REPO,
 432        JUNK_LEAVE_ALL
 433} junk_mode = JUNK_LEAVE_NONE;
 434
 435static const char junk_leave_repo_msg[] =
 436N_("Clone succeeded, but checkout failed.\n"
 437   "You can inspect what was checked out with 'git status'\n"
 438   "and retry the checkout with 'git checkout -f HEAD'\n");
 439
 440static void remove_junk(void)
 441{
 442        struct strbuf sb = STRBUF_INIT;
 443
 444        switch (junk_mode) {
 445        case JUNK_LEAVE_REPO:
 446                warning("%s", _(junk_leave_repo_msg));
 447                /* fall-through */
 448        case JUNK_LEAVE_ALL:
 449                return;
 450        default:
 451                /* proceed to removal */
 452                break;
 453        }
 454
 455        if (junk_git_dir) {
 456                strbuf_addstr(&sb, junk_git_dir);
 457                remove_dir_recursively(&sb, 0);
 458                strbuf_reset(&sb);
 459        }
 460        if (junk_work_tree) {
 461                strbuf_addstr(&sb, junk_work_tree);
 462                remove_dir_recursively(&sb, 0);
 463                strbuf_reset(&sb);
 464        }
 465}
 466
 467static void remove_junk_on_signal(int signo)
 468{
 469        remove_junk();
 470        sigchain_pop(signo);
 471        raise(signo);
 472}
 473
 474static struct ref *find_remote_branch(const struct ref *refs, const char *branch)
 475{
 476        struct ref *ref;
 477        struct strbuf head = STRBUF_INIT;
 478        strbuf_addstr(&head, "refs/heads/");
 479        strbuf_addstr(&head, branch);
 480        ref = find_ref_by_name(refs, head.buf);
 481        strbuf_release(&head);
 482
 483        if (ref)
 484                return ref;
 485
 486        strbuf_addstr(&head, "refs/tags/");
 487        strbuf_addstr(&head, branch);
 488        ref = find_ref_by_name(refs, head.buf);
 489        strbuf_release(&head);
 490
 491        return ref;
 492}
 493
 494static struct ref *wanted_peer_refs(const struct ref *refs,
 495                struct refspec *refspec)
 496{
 497        struct ref *head = copy_ref(find_ref_by_name(refs, "HEAD"));
 498        struct ref *local_refs = head;
 499        struct ref **tail = head ? &head->next : &local_refs;
 500
 501        if (option_single_branch) {
 502                struct ref *remote_head = NULL;
 503
 504                if (!option_branch)
 505                        remote_head = guess_remote_head(head, refs, 0);
 506                else {
 507                        local_refs = NULL;
 508                        tail = &local_refs;
 509                        remote_head = copy_ref(find_remote_branch(refs, option_branch));
 510                }
 511
 512                if (!remote_head && option_branch)
 513                        warning(_("Could not find remote branch %s to clone."),
 514                                option_branch);
 515                else {
 516                        get_fetch_map(remote_head, refspec, &tail, 0);
 517
 518                        /* if --branch=tag, pull the requested tag explicitly */
 519                        get_fetch_map(remote_head, tag_refspec, &tail, 0);
 520                }
 521        } else
 522                get_fetch_map(refs, refspec, &tail, 0);
 523
 524        if (!option_mirror && !option_single_branch)
 525                get_fetch_map(refs, tag_refspec, &tail, 0);
 526
 527        return local_refs;
 528}
 529
 530static void write_remote_refs(const struct ref *local_refs)
 531{
 532        const struct ref *r;
 533
 534        struct ref_transaction *t;
 535        struct strbuf err = STRBUF_INIT;
 536
 537        t = ref_transaction_begin(&err);
 538        if (!t)
 539                die("%s", err.buf);
 540
 541        for (r = local_refs; r; r = r->next) {
 542                if (!r->peer_ref)
 543                        continue;
 544                if (ref_transaction_create(t, r->peer_ref->name, r->old_oid.hash,
 545                                           0, NULL, &err))
 546                        die("%s", err.buf);
 547        }
 548
 549        if (initial_ref_transaction_commit(t, &err))
 550                die("%s", err.buf);
 551
 552        strbuf_release(&err);
 553        ref_transaction_free(t);
 554}
 555
 556static void write_followtags(const struct ref *refs, const char *msg)
 557{
 558        const struct ref *ref;
 559        for (ref = refs; ref; ref = ref->next) {
 560                if (!starts_with(ref->name, "refs/tags/"))
 561                        continue;
 562                if (ends_with(ref->name, "^{}"))
 563                        continue;
 564                if (!has_object_file(&ref->old_oid))
 565                        continue;
 566                update_ref(msg, ref->name, ref->old_oid.hash,
 567                           NULL, 0, UPDATE_REFS_DIE_ON_ERR);
 568        }
 569}
 570
 571static int iterate_ref_map(void *cb_data, unsigned char sha1[20])
 572{
 573        struct ref **rm = cb_data;
 574        struct ref *ref = *rm;
 575
 576        /*
 577         * Skip anything missing a peer_ref, which we are not
 578         * actually going to write a ref for.
 579         */
 580        while (ref && !ref->peer_ref)
 581                ref = ref->next;
 582        /* Returning -1 notes "end of list" to the caller. */
 583        if (!ref)
 584                return -1;
 585
 586        hashcpy(sha1, ref->old_oid.hash);
 587        *rm = ref->next;
 588        return 0;
 589}
 590
 591static void update_remote_refs(const struct ref *refs,
 592                               const struct ref *mapped_refs,
 593                               const struct ref *remote_head_points_at,
 594                               const char *branch_top,
 595                               const char *msg,
 596                               struct transport *transport,
 597                               int check_connectivity)
 598{
 599        const struct ref *rm = mapped_refs;
 600
 601        if (check_connectivity) {
 602                struct check_connected_options opt = CHECK_CONNECTED_INIT;
 603
 604                opt.transport = transport;
 605                opt.progress = transport->progress;
 606
 607                if (check_connected(iterate_ref_map, &rm, &opt))
 608                        die(_("remote did not send all necessary objects"));
 609        }
 610
 611        if (refs) {
 612                write_remote_refs(mapped_refs);
 613                if (option_single_branch)
 614                        write_followtags(refs, msg);
 615        }
 616
 617        if (remote_head_points_at && !option_bare) {
 618                struct strbuf head_ref = STRBUF_INIT;
 619                strbuf_addstr(&head_ref, branch_top);
 620                strbuf_addstr(&head_ref, "HEAD");
 621                if (create_symref(head_ref.buf,
 622                                  remote_head_points_at->peer_ref->name,
 623                                  msg) < 0)
 624                        die(_("unable to update %s"), head_ref.buf);
 625                strbuf_release(&head_ref);
 626        }
 627}
 628
 629static void update_head(const struct ref *our, const struct ref *remote,
 630                        const char *msg)
 631{
 632        const char *head;
 633        if (our && skip_prefix(our->name, "refs/heads/", &head)) {
 634                /* Local default branch link */
 635                if (create_symref("HEAD", our->name, NULL) < 0)
 636                        die(_("unable to update HEAD"));
 637                if (!option_bare) {
 638                        update_ref(msg, "HEAD", our->old_oid.hash, NULL, 0,
 639                                   UPDATE_REFS_DIE_ON_ERR);
 640                        install_branch_config(0, head, option_origin, our->name);
 641                }
 642        } else if (our) {
 643                struct commit *c = lookup_commit_reference(our->old_oid.hash);
 644                /* --branch specifies a non-branch (i.e. tags), detach HEAD */
 645                update_ref(msg, "HEAD", c->object.oid.hash,
 646                           NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
 647        } else if (remote) {
 648                /*
 649                 * We know remote HEAD points to a non-branch, or
 650                 * HEAD points to a branch but we don't know which one.
 651                 * Detach HEAD in all these cases.
 652                 */
 653                update_ref(msg, "HEAD", remote->old_oid.hash,
 654                           NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
 655        }
 656}
 657
 658static int checkout(void)
 659{
 660        unsigned char sha1[20];
 661        char *head;
 662        struct lock_file *lock_file;
 663        struct unpack_trees_options opts;
 664        struct tree *tree;
 665        struct tree_desc t;
 666        int err = 0;
 667
 668        if (option_no_checkout)
 669                return 0;
 670
 671        head = resolve_refdup("HEAD", RESOLVE_REF_READING, sha1, NULL);
 672        if (!head) {
 673                warning(_("remote HEAD refers to nonexistent ref, "
 674                          "unable to checkout.\n"));
 675                return 0;
 676        }
 677        if (!strcmp(head, "HEAD")) {
 678                if (advice_detached_head)
 679                        detach_advice(sha1_to_hex(sha1));
 680        } else {
 681                if (!starts_with(head, "refs/heads/"))
 682                        die(_("HEAD not found below refs/heads!"));
 683        }
 684        free(head);
 685
 686        /* We need to be in the new work tree for the checkout */
 687        setup_work_tree();
 688
 689        lock_file = xcalloc(1, sizeof(struct lock_file));
 690        hold_locked_index(lock_file, 1);
 691
 692        memset(&opts, 0, sizeof opts);
 693        opts.update = 1;
 694        opts.merge = 1;
 695        opts.fn = oneway_merge;
 696        opts.verbose_update = (option_verbosity >= 0);
 697        opts.src_index = &the_index;
 698        opts.dst_index = &the_index;
 699
 700        tree = parse_tree_indirect(sha1);
 701        parse_tree(tree);
 702        init_tree_desc(&t, tree->buffer, tree->size);
 703        if (unpack_trees(1, &t, &opts) < 0)
 704                die(_("unable to checkout working tree"));
 705
 706        if (write_locked_index(&the_index, lock_file, COMMIT_LOCK))
 707                die(_("unable to write new index file"));
 708
 709        err |= run_hook_le(NULL, "post-checkout", sha1_to_hex(null_sha1),
 710                           sha1_to_hex(sha1), "1", NULL);
 711
 712        if (!err && option_recursive) {
 713                struct argv_array args = ARGV_ARRAY_INIT;
 714                argv_array_pushl(&args, "submodule", "update", "--init", "--recursive", NULL);
 715
 716                if (option_shallow_submodules == 1)
 717                        argv_array_push(&args, "--depth=1");
 718
 719                if (max_jobs != -1)
 720                        argv_array_pushf(&args, "--jobs=%d", max_jobs);
 721
 722                err = run_command_v_opt(args.argv, RUN_GIT_CMD);
 723                argv_array_clear(&args);
 724        }
 725
 726        return err;
 727}
 728
 729static int write_one_config(const char *key, const char *value, void *data)
 730{
 731        return git_config_set_multivar_gently(key, value ? value : "true", "^$", 0);
 732}
 733
 734static void write_config(struct string_list *config)
 735{
 736        int i;
 737
 738        for (i = 0; i < config->nr; i++) {
 739                if (git_config_parse_parameter(config->items[i].string,
 740                                               write_one_config, NULL) < 0)
 741                        die(_("unable to write parameters to config file"));
 742        }
 743}
 744
 745static void write_refspec_config(const char *src_ref_prefix,
 746                const struct ref *our_head_points_at,
 747                const struct ref *remote_head_points_at,
 748                struct strbuf *branch_top)
 749{
 750        struct strbuf key = STRBUF_INIT;
 751        struct strbuf value = STRBUF_INIT;
 752
 753        if (option_mirror || !option_bare) {
 754                if (option_single_branch && !option_mirror) {
 755                        if (option_branch) {
 756                                if (starts_with(our_head_points_at->name, "refs/tags/"))
 757                                        strbuf_addf(&value, "+%s:%s", our_head_points_at->name,
 758                                                our_head_points_at->name);
 759                                else
 760                                        strbuf_addf(&value, "+%s:%s%s", our_head_points_at->name,
 761                                                branch_top->buf, option_branch);
 762                        } else if (remote_head_points_at) {
 763                                const char *head = remote_head_points_at->name;
 764                                if (!skip_prefix(head, "refs/heads/", &head))
 765                                        die("BUG: remote HEAD points at non-head?");
 766
 767                                strbuf_addf(&value, "+%s:%s%s", remote_head_points_at->name,
 768                                                branch_top->buf, head);
 769                        }
 770                        /*
 771                         * otherwise, the next "git fetch" will
 772                         * simply fetch from HEAD without updating
 773                         * any remote-tracking branch, which is what
 774                         * we want.
 775                         */
 776                } else {
 777                        strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top->buf);
 778                }
 779                /* Configure the remote */
 780                if (value.len) {
 781                        strbuf_addf(&key, "remote.%s.fetch", option_origin);
 782                        git_config_set_multivar(key.buf, value.buf, "^$", 0);
 783                        strbuf_reset(&key);
 784
 785                        if (option_mirror) {
 786                                strbuf_addf(&key, "remote.%s.mirror", option_origin);
 787                                git_config_set(key.buf, "true");
 788                                strbuf_reset(&key);
 789                        }
 790                }
 791        }
 792
 793        strbuf_release(&key);
 794        strbuf_release(&value);
 795}
 796
 797static void dissociate_from_references(void)
 798{
 799        static const char* argv[] = { "repack", "-a", "-d", NULL };
 800        char *alternates = git_pathdup("objects/info/alternates");
 801
 802        if (!access(alternates, F_OK)) {
 803                if (run_command_v_opt(argv, RUN_GIT_CMD|RUN_COMMAND_NO_STDIN))
 804                        die(_("cannot repack to clean up"));
 805                if (unlink(alternates) && errno != ENOENT)
 806                        die_errno(_("cannot unlink temporary alternates file"));
 807        }
 808        free(alternates);
 809}
 810
 811int cmd_clone(int argc, const char **argv, const char *prefix)
 812{
 813        int is_bundle = 0, is_local;
 814        struct stat buf;
 815        const char *repo_name, *repo, *work_tree, *git_dir;
 816        char *path, *dir;
 817        int dest_exists;
 818        const struct ref *refs, *remote_head;
 819        const struct ref *remote_head_points_at;
 820        const struct ref *our_head_points_at;
 821        struct ref *mapped_refs;
 822        const struct ref *ref;
 823        struct strbuf key = STRBUF_INIT, value = STRBUF_INIT;
 824        struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
 825        struct transport *transport = NULL;
 826        const char *src_ref_prefix = "refs/heads/";
 827        struct remote *remote;
 828        int err = 0, complete_refs_before_fetch = 1;
 829
 830        struct refspec *refspec;
 831        const char *fetch_pattern;
 832
 833        packet_trace_identity("clone");
 834        argc = parse_options(argc, argv, prefix, builtin_clone_options,
 835                             builtin_clone_usage, 0);
 836
 837        if (argc > 2)
 838                usage_msg_opt(_("Too many arguments."),
 839                        builtin_clone_usage, builtin_clone_options);
 840
 841        if (argc == 0)
 842                usage_msg_opt(_("You must specify a repository to clone."),
 843                        builtin_clone_usage, builtin_clone_options);
 844
 845        if (option_single_branch == -1)
 846                option_single_branch = option_depth ? 1 : 0;
 847
 848        if (option_mirror)
 849                option_bare = 1;
 850
 851        if (option_bare) {
 852                if (option_origin)
 853                        die(_("--bare and --origin %s options are incompatible."),
 854                            option_origin);
 855                if (real_git_dir)
 856                        die(_("--bare and --separate-git-dir are incompatible."));
 857                option_no_checkout = 1;
 858        }
 859
 860        if (!option_origin)
 861                option_origin = "origin";
 862
 863        repo_name = argv[0];
 864
 865        path = get_repo_path(repo_name, &is_bundle);
 866        if (path)
 867                repo = xstrdup(absolute_path(repo_name));
 868        else if (!strchr(repo_name, ':'))
 869                die(_("repository '%s' does not exist"), repo_name);
 870        else
 871                repo = repo_name;
 872
 873        /* no need to be strict, transport_set_option() will validate it again */
 874        if (option_depth && atoi(option_depth) < 1)
 875                die(_("depth %s is not a positive number"), option_depth);
 876
 877        if (argc == 2)
 878                dir = xstrdup(argv[1]);
 879        else
 880                dir = guess_dir_name(repo_name, is_bundle, option_bare);
 881        strip_trailing_slashes(dir);
 882
 883        dest_exists = !stat(dir, &buf);
 884        if (dest_exists && !is_empty_dir(dir))
 885                die(_("destination path '%s' already exists and is not "
 886                        "an empty directory."), dir);
 887
 888        strbuf_addf(&reflog_msg, "clone: from %s", repo);
 889
 890        if (option_bare)
 891                work_tree = NULL;
 892        else {
 893                work_tree = getenv("GIT_WORK_TREE");
 894                if (work_tree && !stat(work_tree, &buf))
 895                        die(_("working tree '%s' already exists."), work_tree);
 896        }
 897
 898        if (option_bare || work_tree)
 899                git_dir = xstrdup(dir);
 900        else {
 901                work_tree = dir;
 902                git_dir = mkpathdup("%s/.git", dir);
 903        }
 904
 905        atexit(remove_junk);
 906        sigchain_push_common(remove_junk_on_signal);
 907
 908        if (!option_bare) {
 909                if (safe_create_leading_directories_const(work_tree) < 0)
 910                        die_errno(_("could not create leading directories of '%s'"),
 911                                  work_tree);
 912                if (!dest_exists && mkdir(work_tree, 0777))
 913                        die_errno(_("could not create work tree dir '%s'"),
 914                                  work_tree);
 915                junk_work_tree = work_tree;
 916                set_git_work_tree(work_tree);
 917        }
 918
 919        junk_git_dir = git_dir;
 920        if (safe_create_leading_directories_const(git_dir) < 0)
 921                die(_("could not create leading directories of '%s'"), git_dir);
 922
 923        set_git_dir_init(git_dir, real_git_dir, 0);
 924        if (real_git_dir) {
 925                git_dir = real_git_dir;
 926                junk_git_dir = real_git_dir;
 927        }
 928
 929        if (0 <= option_verbosity) {
 930                if (option_bare)
 931                        fprintf(stderr, _("Cloning into bare repository '%s'...\n"), dir);
 932                else
 933                        fprintf(stderr, _("Cloning into '%s'...\n"), dir);
 934        }
 935        init_db(option_template, INIT_DB_QUIET);
 936        write_config(&option_config);
 937
 938        git_config(git_default_config, NULL);
 939
 940        if (option_bare) {
 941                if (option_mirror)
 942                        src_ref_prefix = "refs/";
 943                strbuf_addstr(&branch_top, src_ref_prefix);
 944
 945                git_config_set("core.bare", "true");
 946        } else {
 947                strbuf_addf(&branch_top, "refs/remotes/%s/", option_origin);
 948        }
 949
 950        strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top.buf);
 951        strbuf_addf(&key, "remote.%s.url", option_origin);
 952        git_config_set(key.buf, repo);
 953        strbuf_reset(&key);
 954
 955        if (option_reference.nr)
 956                setup_reference();
 957
 958        fetch_pattern = value.buf;
 959        refspec = parse_fetch_refspec(1, &fetch_pattern);
 960
 961        strbuf_reset(&value);
 962
 963        remote = remote_get(option_origin);
 964        transport = transport_get(remote, remote->url[0]);
 965        transport_set_verbosity(transport, option_verbosity, option_progress);
 966        transport->family = family;
 967
 968        path = get_repo_path(remote->url[0], &is_bundle);
 969        is_local = option_local != 0 && path && !is_bundle;
 970        if (is_local) {
 971                if (option_depth)
 972                        warning(_("--depth is ignored in local clones; use file:// instead."));
 973                if (!access(mkpath("%s/shallow", path), F_OK)) {
 974                        if (option_local > 0)
 975                                warning(_("source repository is shallow, ignoring --local"));
 976                        is_local = 0;
 977                }
 978        }
 979        if (option_local > 0 && !is_local)
 980                warning(_("--local is ignored"));
 981        transport->cloning = 1;
 982
 983        if (!transport->get_refs_list || (!is_local && !transport->fetch))
 984                die(_("Don't know how to clone %s"), transport->url);
 985
 986        transport_set_option(transport, TRANS_OPT_KEEP, "yes");
 987
 988        if (option_depth)
 989                transport_set_option(transport, TRANS_OPT_DEPTH,
 990                                     option_depth);
 991        if (option_single_branch)
 992                transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
 993
 994        if (option_upload_pack)
 995                transport_set_option(transport, TRANS_OPT_UPLOADPACK,
 996                                     option_upload_pack);
 997
 998        if (transport->smart_options && !option_depth)
 999                transport->smart_options->check_self_contained_and_connected = 1;
1000
1001        refs = transport_get_remote_refs(transport);
1002
1003        if (refs) {
1004                mapped_refs = wanted_peer_refs(refs, refspec);
1005                /*
1006                 * transport_get_remote_refs() may return refs with null sha-1
1007                 * in mapped_refs (see struct transport->get_refs_list
1008                 * comment). In that case we need fetch it early because
1009                 * remote_head code below relies on it.
1010                 *
1011                 * for normal clones, transport_get_remote_refs() should
1012                 * return reliable ref set, we can delay cloning until after
1013                 * remote HEAD check.
1014                 */
1015                for (ref = refs; ref; ref = ref->next)
1016                        if (is_null_oid(&ref->old_oid)) {
1017                                complete_refs_before_fetch = 0;
1018                                break;
1019                        }
1020
1021                if (!is_local && !complete_refs_before_fetch)
1022                        transport_fetch_refs(transport, mapped_refs);
1023
1024                remote_head = find_ref_by_name(refs, "HEAD");
1025                remote_head_points_at =
1026                        guess_remote_head(remote_head, mapped_refs, 0);
1027
1028                if (option_branch) {
1029                        our_head_points_at =
1030                                find_remote_branch(mapped_refs, option_branch);
1031
1032                        if (!our_head_points_at)
1033                                die(_("Remote branch %s not found in upstream %s"),
1034                                    option_branch, option_origin);
1035                }
1036                else
1037                        our_head_points_at = remote_head_points_at;
1038        }
1039        else {
1040                if (option_branch)
1041                        die(_("Remote branch %s not found in upstream %s"),
1042                                        option_branch, option_origin);
1043
1044                warning(_("You appear to have cloned an empty repository."));
1045                mapped_refs = NULL;
1046                our_head_points_at = NULL;
1047                remote_head_points_at = NULL;
1048                remote_head = NULL;
1049                option_no_checkout = 1;
1050                if (!option_bare)
1051                        install_branch_config(0, "master", option_origin,
1052                                              "refs/heads/master");
1053        }
1054
1055        write_refspec_config(src_ref_prefix, our_head_points_at,
1056                        remote_head_points_at, &branch_top);
1057
1058        if (is_local)
1059                clone_local(path, git_dir);
1060        else if (refs && complete_refs_before_fetch)
1061                transport_fetch_refs(transport, mapped_refs);
1062
1063        update_remote_refs(refs, mapped_refs, remote_head_points_at,
1064                           branch_top.buf, reflog_msg.buf, transport, !is_local);
1065
1066        update_head(our_head_points_at, remote_head, reflog_msg.buf);
1067
1068        transport_unlock_pack(transport);
1069        transport_disconnect(transport);
1070
1071        if (option_dissociate) {
1072                close_all_packs();
1073                dissociate_from_references();
1074        }
1075
1076        junk_mode = JUNK_LEAVE_REPO;
1077        err = checkout();
1078
1079        strbuf_release(&reflog_msg);
1080        strbuf_release(&branch_top);
1081        strbuf_release(&key);
1082        strbuf_release(&value);
1083        junk_mode = JUNK_LEAVE_ALL;
1084
1085        free(refspec);
1086        return err;
1087}