Merge branch 'ah/fix-http-push' into maint
[git] / builtin / clone.c
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 "parse-options.h"
13 #include "fetch-pack.h"
14 #include "refs.h"
15 #include "tree.h"
16 #include "tree-walk.h"
17 #include "unpack-trees.h"
18 #include "transport.h"
19 #include "strbuf.h"
20 #include "dir.h"
21 #include "sigchain.h"
22 #include "branch.h"
23 #include "remote.h"
24 #include "run-command.h"
25 #include "connected.h"
26
27 /*
28  * Overall FIXMEs:
29  *  - respect DB_ENVIRONMENT for .git/objects.
30  *
31  * Implementation notes:
32  *  - dropping use-separate-remote and no-separate-remote compatibility
33  *
34  */
35 static const char * const builtin_clone_usage[] = {
36         N_("git clone [options] [--] <repo> [<dir>]"),
37         NULL
38 };
39
40 static int option_no_checkout, option_bare, option_mirror, option_single_branch = -1;
41 static int option_local = -1, option_no_hardlinks, option_shared, option_recursive;
42 static char *option_template, *option_depth;
43 static char *option_origin = NULL;
44 static char *option_branch = NULL;
45 static const char *real_git_dir;
46 static char *option_upload_pack = "git-upload-pack";
47 static int option_verbosity;
48 static int option_progress = -1;
49 static struct string_list option_config;
50 static struct string_list option_reference;
51
52 static int opt_parse_reference(const struct option *opt, const char *arg, int unset)
53 {
54         struct string_list *option_reference = opt->value;
55         if (!arg)
56                 return -1;
57         string_list_append(option_reference, arg);
58         return 0;
59 }
60
61 static struct option builtin_clone_options[] = {
62         OPT__VERBOSITY(&option_verbosity),
63         OPT_BOOL(0, "progress", &option_progress,
64                  N_("force progress reporting")),
65         OPT_BOOL('n', "no-checkout", &option_no_checkout,
66                  N_("don't create a checkout")),
67         OPT_BOOL(0, "bare", &option_bare, N_("create a bare repository")),
68         OPT_HIDDEN_BOOL(0, "naked", &option_bare,
69                         N_("create a bare repository")),
70         OPT_BOOL(0, "mirror", &option_mirror,
71                  N_("create a mirror repository (implies bare)")),
72         OPT_BOOL('l', "local", &option_local,
73                 N_("to clone from a local repository")),
74         OPT_BOOL(0, "no-hardlinks", &option_no_hardlinks,
75                     N_("don't use local hardlinks, always copy")),
76         OPT_BOOL('s', "shared", &option_shared,
77                     N_("setup as shared repository")),
78         OPT_BOOL(0, "recursive", &option_recursive,
79                     N_("initialize submodules in the clone")),
80         OPT_BOOL(0, "recurse-submodules", &option_recursive,
81                     N_("initialize submodules in the clone")),
82         OPT_STRING(0, "template", &option_template, N_("template-directory"),
83                    N_("directory from which templates will be used")),
84         OPT_CALLBACK(0 , "reference", &option_reference, N_("repo"),
85                      N_("reference repository"), &opt_parse_reference),
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_STRING(0, "separate-git-dir", &real_git_dir, N_("gitdir"),
97                    N_("separate git dir from working tree")),
98         OPT_STRING_LIST('c', "config", &option_config, N_("key=value"),
99                         N_("set config inside the new repository")),
100         OPT_END()
101 };
102
103 static const char *argv_submodule[] = {
104         "submodule", "update", "--init", "--recursive", NULL
105 };
106
107 static char *get_repo_path(const char *repo, int *is_bundle)
108 {
109         static char *suffix[] = { "/.git", "", ".git/.git", ".git" };
110         static char *bundle_suffix[] = { ".bundle", "" };
111         struct stat st;
112         int i;
113
114         for (i = 0; i < ARRAY_SIZE(suffix); i++) {
115                 const char *path;
116                 path = mkpath("%s%s", repo, suffix[i]);
117                 if (stat(path, &st))
118                         continue;
119                 if (S_ISDIR(st.st_mode) && is_git_directory(path)) {
120                         *is_bundle = 0;
121                         return xstrdup(absolute_path(path));
122                 } else if (S_ISREG(st.st_mode) && st.st_size > 8) {
123                         /* Is it a "gitfile"? */
124                         char signature[8];
125                         int len, fd = open(path, O_RDONLY);
126                         if (fd < 0)
127                                 continue;
128                         len = read_in_full(fd, signature, 8);
129                         close(fd);
130                         if (len != 8 || strncmp(signature, "gitdir: ", 8))
131                                 continue;
132                         path = read_gitfile(path);
133                         if (path) {
134                                 *is_bundle = 0;
135                                 return xstrdup(absolute_path(path));
136                         }
137                 }
138         }
139
140         for (i = 0; i < ARRAY_SIZE(bundle_suffix); i++) {
141                 const char *path;
142                 path = mkpath("%s%s", repo, bundle_suffix[i]);
143                 if (!stat(path, &st) && S_ISREG(st.st_mode)) {
144                         *is_bundle = 1;
145                         return xstrdup(absolute_path(path));
146                 }
147         }
148
149         return NULL;
150 }
151
152 static char *guess_dir_name(const char *repo, int is_bundle, int is_bare)
153 {
154         const char *end = repo + strlen(repo), *start;
155         char *dir;
156
157         /*
158          * Strip trailing spaces, slashes and /.git
159          */
160         while (repo < end && (is_dir_sep(end[-1]) || isspace(end[-1])))
161                 end--;
162         if (end - repo > 5 && is_dir_sep(end[-5]) &&
163             !strncmp(end - 4, ".git", 4)) {
164                 end -= 5;
165                 while (repo < end && is_dir_sep(end[-1]))
166                         end--;
167         }
168
169         /*
170          * Find last component, but be prepared that repo could have
171          * the form  "remote.example.com:foo.git", i.e. no slash
172          * in the directory part.
173          */
174         start = end;
175         while (repo < start && !is_dir_sep(start[-1]) && start[-1] != ':')
176                 start--;
177
178         /*
179          * Strip .{bundle,git}.
180          */
181         if (is_bundle) {
182                 if (end - start > 7 && !strncmp(end - 7, ".bundle", 7))
183                         end -= 7;
184         } else {
185                 if (end - start > 4 && !strncmp(end - 4, ".git", 4))
186                         end -= 4;
187         }
188
189         if (is_bare) {
190                 struct strbuf result = STRBUF_INIT;
191                 strbuf_addf(&result, "%.*s.git", (int)(end - start), start);
192                 dir = strbuf_detach(&result, NULL);
193         } else
194                 dir = xstrndup(start, end - start);
195         /*
196          * Replace sequences of 'control' characters and whitespace
197          * with one ascii space, remove leading and trailing spaces.
198          */
199         if (*dir) {
200                 char *out = dir;
201                 int prev_space = 1 /* strip leading whitespace */;
202                 for (end = dir; *end; ++end) {
203                         char ch = *end;
204                         if ((unsigned char)ch < '\x20')
205                                 ch = '\x20';
206                         if (isspace(ch)) {
207                                 if (prev_space)
208                                         continue;
209                                 prev_space = 1;
210                         } else
211                                 prev_space = 0;
212                         *out++ = ch;
213                 }
214                 *out = '\0';
215                 if (out > dir && prev_space)
216                         out[-1] = '\0';
217         }
218         return dir;
219 }
220
221 static void strip_trailing_slashes(char *dir)
222 {
223         char *end = dir + strlen(dir);
224
225         while (dir < end - 1 && is_dir_sep(end[-1]))
226                 end--;
227         *end = '\0';
228 }
229
230 static int add_one_reference(struct string_list_item *item, void *cb_data)
231 {
232         char *ref_git;
233         const char *repo;
234         struct strbuf alternate = STRBUF_INIT;
235
236         /* Beware: read_gitfile(), real_path() and mkpath() return static buffer */
237         ref_git = xstrdup(real_path(item->string));
238
239         repo = read_gitfile(ref_git);
240         if (!repo)
241                 repo = read_gitfile(mkpath("%s/.git", ref_git));
242         if (repo) {
243                 free(ref_git);
244                 ref_git = xstrdup(repo);
245         }
246
247         if (!repo && is_directory(mkpath("%s/.git/objects", ref_git))) {
248                 char *ref_git_git = mkpathdup("%s/.git", ref_git);
249                 free(ref_git);
250                 ref_git = ref_git_git;
251         } else if (!is_directory(mkpath("%s/objects", ref_git)))
252                 die(_("reference repository '%s' is not a local repository."),
253                     item->string);
254
255         if (!access(mkpath("%s/shallow", ref_git), F_OK))
256                 die(_("reference repository '%s' is shallow"), item->string);
257
258         if (!access(mkpath("%s/info/grafts", ref_git), F_OK))
259                 die(_("reference repository '%s' is grafted"), item->string);
260
261         strbuf_addf(&alternate, "%s/objects", ref_git);
262         add_to_alternates_file(alternate.buf);
263         strbuf_release(&alternate);
264         free(ref_git);
265         return 0;
266 }
267
268 static void setup_reference(void)
269 {
270         for_each_string_list(&option_reference, add_one_reference, NULL);
271 }
272
273 static void copy_alternates(struct strbuf *src, struct strbuf *dst,
274                             const char *src_repo)
275 {
276         /*
277          * Read from the source objects/info/alternates file
278          * and copy the entries to corresponding file in the
279          * destination repository with add_to_alternates_file().
280          * Both src and dst have "$path/objects/info/alternates".
281          *
282          * Instead of copying bit-for-bit from the original,
283          * we need to append to existing one so that the already
284          * created entry via "clone -s" is not lost, and also
285          * to turn entries with paths relative to the original
286          * absolute, so that they can be used in the new repository.
287          */
288         FILE *in = fopen(src->buf, "r");
289         struct strbuf line = STRBUF_INIT;
290
291         while (strbuf_getline(&line, in, '\n') != EOF) {
292                 char *abs_path, abs_buf[PATH_MAX];
293                 if (!line.len || line.buf[0] == '#')
294                         continue;
295                 if (is_absolute_path(line.buf)) {
296                         add_to_alternates_file(line.buf);
297                         continue;
298                 }
299                 abs_path = mkpath("%s/objects/%s", src_repo, line.buf);
300                 normalize_path_copy(abs_buf, abs_path);
301                 add_to_alternates_file(abs_buf);
302         }
303         strbuf_release(&line);
304         fclose(in);
305 }
306
307 static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
308                                    const char *src_repo, int src_baselen)
309 {
310         struct dirent *de;
311         struct stat buf;
312         int src_len, dest_len;
313         DIR *dir;
314
315         dir = opendir(src->buf);
316         if (!dir)
317                 die_errno(_("failed to open '%s'"), src->buf);
318
319         if (mkdir(dest->buf, 0777)) {
320                 if (errno != EEXIST)
321                         die_errno(_("failed to create directory '%s'"), dest->buf);
322                 else if (stat(dest->buf, &buf))
323                         die_errno(_("failed to stat '%s'"), dest->buf);
324                 else if (!S_ISDIR(buf.st_mode))
325                         die(_("%s exists and is not a directory"), dest->buf);
326         }
327
328         strbuf_addch(src, '/');
329         src_len = src->len;
330         strbuf_addch(dest, '/');
331         dest_len = dest->len;
332
333         while ((de = readdir(dir)) != NULL) {
334                 strbuf_setlen(src, src_len);
335                 strbuf_addstr(src, de->d_name);
336                 strbuf_setlen(dest, dest_len);
337                 strbuf_addstr(dest, de->d_name);
338                 if (stat(src->buf, &buf)) {
339                         warning (_("failed to stat %s\n"), src->buf);
340                         continue;
341                 }
342                 if (S_ISDIR(buf.st_mode)) {
343                         if (de->d_name[0] != '.')
344                                 copy_or_link_directory(src, dest,
345                                                        src_repo, src_baselen);
346                         continue;
347                 }
348
349                 /* Files that cannot be copied bit-for-bit... */
350                 if (!strcmp(src->buf + src_baselen, "/info/alternates")) {
351                         copy_alternates(src, dest, src_repo);
352                         continue;
353                 }
354
355                 if (unlink(dest->buf) && errno != ENOENT)
356                         die_errno(_("failed to unlink '%s'"), dest->buf);
357                 if (!option_no_hardlinks) {
358                         if (!link(src->buf, dest->buf))
359                                 continue;
360                         if (option_local > 0)
361                                 die_errno(_("failed to create link '%s'"), dest->buf);
362                         option_no_hardlinks = 1;
363                 }
364                 if (copy_file_with_time(dest->buf, src->buf, 0666))
365                         die_errno(_("failed to copy file to '%s'"), dest->buf);
366         }
367         closedir(dir);
368 }
369
370 static void clone_local(const char *src_repo, const char *dest_repo)
371 {
372         if (option_shared) {
373                 struct strbuf alt = STRBUF_INIT;
374                 strbuf_addf(&alt, "%s/objects", src_repo);
375                 add_to_alternates_file(alt.buf);
376                 strbuf_release(&alt);
377         } else {
378                 struct strbuf src = STRBUF_INIT;
379                 struct strbuf dest = STRBUF_INIT;
380                 strbuf_addf(&src, "%s/objects", src_repo);
381                 strbuf_addf(&dest, "%s/objects", dest_repo);
382                 copy_or_link_directory(&src, &dest, src_repo, src.len);
383                 strbuf_release(&src);
384                 strbuf_release(&dest);
385         }
386
387         if (0 <= option_verbosity)
388                 fprintf(stderr, _("done.\n"));
389 }
390
391 static const char *junk_work_tree;
392 static const char *junk_git_dir;
393 static pid_t junk_pid;
394 static enum {
395         JUNK_LEAVE_NONE,
396         JUNK_LEAVE_REPO,
397         JUNK_LEAVE_ALL
398 } junk_mode = JUNK_LEAVE_NONE;
399
400 static const char junk_leave_repo_msg[] =
401 N_("Clone succeeded, but checkout failed.\n"
402    "You can inspect what was checked out with 'git status'\n"
403    "and retry the checkout with 'git checkout -f HEAD'\n");
404
405 static void remove_junk(void)
406 {
407         struct strbuf sb = STRBUF_INIT;
408
409         switch (junk_mode) {
410         case JUNK_LEAVE_REPO:
411                 warning("%s", _(junk_leave_repo_msg));
412                 /* fall-through */
413         case JUNK_LEAVE_ALL:
414                 return;
415         default:
416                 /* proceed to removal */
417                 break;
418         }
419
420         if (getpid() != junk_pid)
421                 return;
422         if (junk_git_dir) {
423                 strbuf_addstr(&sb, junk_git_dir);
424                 remove_dir_recursively(&sb, 0);
425                 strbuf_reset(&sb);
426         }
427         if (junk_work_tree) {
428                 strbuf_addstr(&sb, junk_work_tree);
429                 remove_dir_recursively(&sb, 0);
430                 strbuf_reset(&sb);
431         }
432 }
433
434 static void remove_junk_on_signal(int signo)
435 {
436         remove_junk();
437         sigchain_pop(signo);
438         raise(signo);
439 }
440
441 static struct ref *find_remote_branch(const struct ref *refs, const char *branch)
442 {
443         struct ref *ref;
444         struct strbuf head = STRBUF_INIT;
445         strbuf_addstr(&head, "refs/heads/");
446         strbuf_addstr(&head, branch);
447         ref = find_ref_by_name(refs, head.buf);
448         strbuf_release(&head);
449
450         if (ref)
451                 return ref;
452
453         strbuf_addstr(&head, "refs/tags/");
454         strbuf_addstr(&head, branch);
455         ref = find_ref_by_name(refs, head.buf);
456         strbuf_release(&head);
457
458         return ref;
459 }
460
461 static struct ref *wanted_peer_refs(const struct ref *refs,
462                 struct refspec *refspec)
463 {
464         struct ref *head = copy_ref(find_ref_by_name(refs, "HEAD"));
465         struct ref *local_refs = head;
466         struct ref **tail = head ? &head->next : &local_refs;
467
468         if (option_single_branch) {
469                 struct ref *remote_head = NULL;
470
471                 if (!option_branch)
472                         remote_head = guess_remote_head(head, refs, 0);
473                 else {
474                         local_refs = NULL;
475                         tail = &local_refs;
476                         remote_head = copy_ref(find_remote_branch(refs, option_branch));
477                 }
478
479                 if (!remote_head && option_branch)
480                         warning(_("Could not find remote branch %s to clone."),
481                                 option_branch);
482                 else {
483                         get_fetch_map(remote_head, refspec, &tail, 0);
484
485                         /* if --branch=tag, pull the requested tag explicitly */
486                         get_fetch_map(remote_head, tag_refspec, &tail, 0);
487                 }
488         } else
489                 get_fetch_map(refs, refspec, &tail, 0);
490
491         if (!option_mirror && !option_single_branch)
492                 get_fetch_map(refs, tag_refspec, &tail, 0);
493
494         return local_refs;
495 }
496
497 static void write_remote_refs(const struct ref *local_refs)
498 {
499         const struct ref *r;
500
501         lock_packed_refs(LOCK_DIE_ON_ERROR);
502
503         for (r = local_refs; r; r = r->next) {
504                 if (!r->peer_ref)
505                         continue;
506                 add_packed_ref(r->peer_ref->name, r->old_sha1);
507         }
508
509         if (commit_packed_refs())
510                 die_errno("unable to overwrite old ref-pack file");
511 }
512
513 static void write_followtags(const struct ref *refs, const char *msg)
514 {
515         const struct ref *ref;
516         for (ref = refs; ref; ref = ref->next) {
517                 if (!starts_with(ref->name, "refs/tags/"))
518                         continue;
519                 if (ends_with(ref->name, "^{}"))
520                         continue;
521                 if (!has_sha1_file(ref->old_sha1))
522                         continue;
523                 update_ref(msg, ref->name, ref->old_sha1,
524                            NULL, 0, DIE_ON_ERR);
525         }
526 }
527
528 static int iterate_ref_map(void *cb_data, unsigned char sha1[20])
529 {
530         struct ref **rm = cb_data;
531         struct ref *ref = *rm;
532
533         /*
534          * Skip anything missing a peer_ref, which we are not
535          * actually going to write a ref for.
536          */
537         while (ref && !ref->peer_ref)
538                 ref = ref->next;
539         /* Returning -1 notes "end of list" to the caller. */
540         if (!ref)
541                 return -1;
542
543         hashcpy(sha1, ref->old_sha1);
544         *rm = ref->next;
545         return 0;
546 }
547
548 static void update_remote_refs(const struct ref *refs,
549                                const struct ref *mapped_refs,
550                                const struct ref *remote_head_points_at,
551                                const char *branch_top,
552                                const char *msg,
553                                struct transport *transport,
554                                int check_connectivity)
555 {
556         const struct ref *rm = mapped_refs;
557
558         if (check_connectivity) {
559                 if (transport->progress)
560                         fprintf(stderr, _("Checking connectivity... "));
561                 if (check_everything_connected_with_transport(iterate_ref_map,
562                                                               0, &rm, transport))
563                         die(_("remote did not send all necessary objects"));
564                 if (transport->progress)
565                         fprintf(stderr, _("done.\n"));
566         }
567
568         if (refs) {
569                 write_remote_refs(mapped_refs);
570                 if (option_single_branch)
571                         write_followtags(refs, msg);
572         }
573
574         if (remote_head_points_at && !option_bare) {
575                 struct strbuf head_ref = STRBUF_INIT;
576                 strbuf_addstr(&head_ref, branch_top);
577                 strbuf_addstr(&head_ref, "HEAD");
578                 create_symref(head_ref.buf,
579                               remote_head_points_at->peer_ref->name,
580                               msg);
581         }
582 }
583
584 static void update_head(const struct ref *our, const struct ref *remote,
585                         const char *msg)
586 {
587         if (our && starts_with(our->name, "refs/heads/")) {
588                 /* Local default branch link */
589                 create_symref("HEAD", our->name, NULL);
590                 if (!option_bare) {
591                         const char *head = skip_prefix(our->name, "refs/heads/");
592                         update_ref(msg, "HEAD", our->old_sha1, NULL, 0, DIE_ON_ERR);
593                         install_branch_config(0, head, option_origin, our->name);
594                 }
595         } else if (our) {
596                 struct commit *c = lookup_commit_reference(our->old_sha1);
597                 /* --branch specifies a non-branch (i.e. tags), detach HEAD */
598                 update_ref(msg, "HEAD", c->object.sha1,
599                            NULL, REF_NODEREF, DIE_ON_ERR);
600         } else if (remote) {
601                 /*
602                  * We know remote HEAD points to a non-branch, or
603                  * HEAD points to a branch but we don't know which one.
604                  * Detach HEAD in all these cases.
605                  */
606                 update_ref(msg, "HEAD", remote->old_sha1,
607                            NULL, REF_NODEREF, DIE_ON_ERR);
608         }
609 }
610
611 static int checkout(void)
612 {
613         unsigned char sha1[20];
614         char *head;
615         struct lock_file *lock_file;
616         struct unpack_trees_options opts;
617         struct tree *tree;
618         struct tree_desc t;
619         int err = 0, fd;
620
621         if (option_no_checkout)
622                 return 0;
623
624         head = resolve_refdup("HEAD", sha1, 1, NULL);
625         if (!head) {
626                 warning(_("remote HEAD refers to nonexistent ref, "
627                           "unable to checkout.\n"));
628                 return 0;
629         }
630         if (!strcmp(head, "HEAD")) {
631                 if (advice_detached_head)
632                         detach_advice(sha1_to_hex(sha1));
633         } else {
634                 if (!starts_with(head, "refs/heads/"))
635                         die(_("HEAD not found below refs/heads!"));
636         }
637         free(head);
638
639         /* We need to be in the new work tree for the checkout */
640         setup_work_tree();
641
642         lock_file = xcalloc(1, sizeof(struct lock_file));
643         fd = hold_locked_index(lock_file, 1);
644
645         memset(&opts, 0, sizeof opts);
646         opts.update = 1;
647         opts.merge = 1;
648         opts.fn = oneway_merge;
649         opts.verbose_update = (option_verbosity >= 0);
650         opts.src_index = &the_index;
651         opts.dst_index = &the_index;
652
653         tree = parse_tree_indirect(sha1);
654         parse_tree(tree);
655         init_tree_desc(&t, tree->buffer, tree->size);
656         if (unpack_trees(1, &t, &opts) < 0)
657                 die(_("unable to checkout working tree"));
658
659         if (write_cache(fd, active_cache, active_nr) ||
660             commit_locked_index(lock_file))
661                 die(_("unable to write new index file"));
662
663         err |= run_hook_le(NULL, "post-checkout", sha1_to_hex(null_sha1),
664                            sha1_to_hex(sha1), "1", NULL);
665
666         if (!err && option_recursive)
667                 err = run_command_v_opt(argv_submodule, RUN_GIT_CMD);
668
669         return err;
670 }
671
672 static int write_one_config(const char *key, const char *value, void *data)
673 {
674         return git_config_set_multivar(key, value ? value : "true", "^$", 0);
675 }
676
677 static void write_config(struct string_list *config)
678 {
679         int i;
680
681         for (i = 0; i < config->nr; i++) {
682                 if (git_config_parse_parameter(config->items[i].string,
683                                                write_one_config, NULL) < 0)
684                         die("unable to write parameters to config file");
685         }
686 }
687
688 static void write_refspec_config(const char* src_ref_prefix,
689                 const struct ref* our_head_points_at,
690                 const struct ref* remote_head_points_at, struct strbuf* branch_top)
691 {
692         struct strbuf key = STRBUF_INIT;
693         struct strbuf value = STRBUF_INIT;
694
695         if (option_mirror || !option_bare) {
696                 if (option_single_branch && !option_mirror) {
697                         if (option_branch) {
698                                 if (starts_with(our_head_points_at->name, "refs/tags/"))
699                                         strbuf_addf(&value, "+%s:%s", our_head_points_at->name,
700                                                 our_head_points_at->name);
701                                 else
702                                         strbuf_addf(&value, "+%s:%s%s", our_head_points_at->name,
703                                                 branch_top->buf, option_branch);
704                         } else if (remote_head_points_at) {
705                                 strbuf_addf(&value, "+%s:%s%s", remote_head_points_at->name,
706                                                 branch_top->buf,
707                                                 skip_prefix(remote_head_points_at->name, "refs/heads/"));
708                         }
709                         /*
710                          * otherwise, the next "git fetch" will
711                          * simply fetch from HEAD without updating
712                          * any remote-tracking branch, which is what
713                          * we want.
714                          */
715                 } else {
716                         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top->buf);
717                 }
718                 /* Configure the remote */
719                 if (value.len) {
720                         strbuf_addf(&key, "remote.%s.fetch", option_origin);
721                         git_config_set_multivar(key.buf, value.buf, "^$", 0);
722                         strbuf_reset(&key);
723
724                         if (option_mirror) {
725                                 strbuf_addf(&key, "remote.%s.mirror", option_origin);
726                                 git_config_set(key.buf, "true");
727                                 strbuf_reset(&key);
728                         }
729                 }
730         }
731
732         strbuf_release(&key);
733         strbuf_release(&value);
734 }
735
736 int cmd_clone(int argc, const char **argv, const char *prefix)
737 {
738         int is_bundle = 0, is_local;
739         struct stat buf;
740         const char *repo_name, *repo, *work_tree, *git_dir;
741         char *path, *dir;
742         int dest_exists;
743         const struct ref *refs, *remote_head;
744         const struct ref *remote_head_points_at;
745         const struct ref *our_head_points_at;
746         struct ref *mapped_refs;
747         const struct ref *ref;
748         struct strbuf key = STRBUF_INIT, value = STRBUF_INIT;
749         struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
750         struct transport *transport = NULL;
751         const char *src_ref_prefix = "refs/heads/";
752         struct remote *remote;
753         int err = 0, complete_refs_before_fetch = 1;
754
755         struct refspec *refspec;
756         const char *fetch_pattern;
757
758         junk_pid = getpid();
759
760         packet_trace_identity("clone");
761         argc = parse_options(argc, argv, prefix, builtin_clone_options,
762                              builtin_clone_usage, 0);
763
764         if (argc > 2)
765                 usage_msg_opt(_("Too many arguments."),
766                         builtin_clone_usage, builtin_clone_options);
767
768         if (argc == 0)
769                 usage_msg_opt(_("You must specify a repository to clone."),
770                         builtin_clone_usage, builtin_clone_options);
771
772         if (option_single_branch == -1)
773                 option_single_branch = option_depth ? 1 : 0;
774
775         if (option_mirror)
776                 option_bare = 1;
777
778         if (option_bare) {
779                 if (option_origin)
780                         die(_("--bare and --origin %s options are incompatible."),
781                             option_origin);
782                 if (real_git_dir)
783                         die(_("--bare and --separate-git-dir are incompatible."));
784                 option_no_checkout = 1;
785         }
786
787         if (!option_origin)
788                 option_origin = "origin";
789
790         repo_name = argv[0];
791
792         path = get_repo_path(repo_name, &is_bundle);
793         if (path)
794                 repo = xstrdup(absolute_path(repo_name));
795         else if (!strchr(repo_name, ':'))
796                 die(_("repository '%s' does not exist"), repo_name);
797         else
798                 repo = repo_name;
799         is_local = option_local != 0 && path && !is_bundle;
800         if (is_local) {
801                 if (option_depth)
802                         warning(_("--depth is ignored in local clones; use file:// instead."));
803                 if (!access(mkpath("%s/shallow", path), F_OK)) {
804                         if (option_local > 0)
805                                 warning(_("source repository is shallow, ignoring --local"));
806                         is_local = 0;
807                 }
808         }
809         if (option_local > 0 && !is_local)
810                 warning(_("--local is ignored"));
811
812         /* no need to be strict, transport_set_option() will validate it again */
813         if (option_depth && atoi(option_depth) < 1)
814                 die(_("depth %s is not a positive number"), option_depth);
815
816         if (argc == 2)
817                 dir = xstrdup(argv[1]);
818         else
819                 dir = guess_dir_name(repo_name, is_bundle, option_bare);
820         strip_trailing_slashes(dir);
821
822         dest_exists = !stat(dir, &buf);
823         if (dest_exists && !is_empty_dir(dir))
824                 die(_("destination path '%s' already exists and is not "
825                         "an empty directory."), dir);
826
827         strbuf_addf(&reflog_msg, "clone: from %s", repo);
828
829         if (option_bare)
830                 work_tree = NULL;
831         else {
832                 work_tree = getenv("GIT_WORK_TREE");
833                 if (work_tree && !stat(work_tree, &buf))
834                         die(_("working tree '%s' already exists."), work_tree);
835         }
836
837         if (option_bare || work_tree)
838                 git_dir = xstrdup(dir);
839         else {
840                 work_tree = dir;
841                 git_dir = mkpathdup("%s/.git", dir);
842         }
843
844         if (!option_bare) {
845                 junk_work_tree = work_tree;
846                 if (safe_create_leading_directories_const(work_tree) < 0)
847                         die_errno(_("could not create leading directories of '%s'"),
848                                   work_tree);
849                 if (!dest_exists && mkdir(work_tree, 0777))
850                         die_errno(_("could not create work tree dir '%s'."),
851                                   work_tree);
852                 set_git_work_tree(work_tree);
853         }
854         junk_git_dir = git_dir;
855         atexit(remove_junk);
856         sigchain_push_common(remove_junk_on_signal);
857
858         if (safe_create_leading_directories_const(git_dir) < 0)
859                 die(_("could not create leading directories of '%s'"), git_dir);
860
861         set_git_dir_init(git_dir, real_git_dir, 0);
862         if (real_git_dir) {
863                 git_dir = real_git_dir;
864                 junk_git_dir = real_git_dir;
865         }
866
867         if (0 <= option_verbosity) {
868                 if (option_bare)
869                         fprintf(stderr, _("Cloning into bare repository '%s'...\n"), dir);
870                 else
871                         fprintf(stderr, _("Cloning into '%s'...\n"), dir);
872         }
873         init_db(option_template, INIT_DB_QUIET);
874         write_config(&option_config);
875
876         git_config(git_default_config, NULL);
877
878         if (option_bare) {
879                 if (option_mirror)
880                         src_ref_prefix = "refs/";
881                 strbuf_addstr(&branch_top, src_ref_prefix);
882
883                 git_config_set("core.bare", "true");
884         } else {
885                 strbuf_addf(&branch_top, "refs/remotes/%s/", option_origin);
886         }
887
888         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top.buf);
889         strbuf_addf(&key, "remote.%s.url", option_origin);
890         git_config_set(key.buf, repo);
891         strbuf_reset(&key);
892
893         if (option_reference.nr)
894                 setup_reference();
895
896         fetch_pattern = value.buf;
897         refspec = parse_fetch_refspec(1, &fetch_pattern);
898
899         strbuf_reset(&value);
900
901         remote = remote_get(option_origin);
902         transport = transport_get(remote, remote->url[0]);
903         transport->cloning = 1;
904
905         if (!transport->get_refs_list || (!is_local && !transport->fetch))
906                 die(_("Don't know how to clone %s"), transport->url);
907
908         transport_set_option(transport, TRANS_OPT_KEEP, "yes");
909
910         if (option_depth)
911                 transport_set_option(transport, TRANS_OPT_DEPTH,
912                                      option_depth);
913         if (option_single_branch)
914                 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
915
916         transport_set_verbosity(transport, option_verbosity, option_progress);
917
918         if (option_upload_pack)
919                 transport_set_option(transport, TRANS_OPT_UPLOADPACK,
920                                      option_upload_pack);
921
922         if (transport->smart_options && !option_depth)
923                 transport->smart_options->check_self_contained_and_connected = 1;
924
925         refs = transport_get_remote_refs(transport);
926
927         if (refs) {
928                 mapped_refs = wanted_peer_refs(refs, refspec);
929                 /*
930                  * transport_get_remote_refs() may return refs with null sha-1
931                  * in mapped_refs (see struct transport->get_refs_list
932                  * comment). In that case we need fetch it early because
933                  * remote_head code below relies on it.
934                  *
935                  * for normal clones, transport_get_remote_refs() should
936                  * return reliable ref set, we can delay cloning until after
937                  * remote HEAD check.
938                  */
939                 for (ref = refs; ref; ref = ref->next)
940                         if (is_null_sha1(ref->old_sha1)) {
941                                 complete_refs_before_fetch = 0;
942                                 break;
943                         }
944
945                 if (!is_local && !complete_refs_before_fetch)
946                         transport_fetch_refs(transport, mapped_refs);
947
948                 remote_head = find_ref_by_name(refs, "HEAD");
949                 remote_head_points_at =
950                         guess_remote_head(remote_head, mapped_refs, 0);
951
952                 if (option_branch) {
953                         our_head_points_at =
954                                 find_remote_branch(mapped_refs, option_branch);
955
956                         if (!our_head_points_at)
957                                 die(_("Remote branch %s not found in upstream %s"),
958                                     option_branch, option_origin);
959                 }
960                 else
961                         our_head_points_at = remote_head_points_at;
962         }
963         else {
964                 if (option_branch)
965                         die(_("Remote branch %s not found in upstream %s"),
966                                         option_branch, option_origin);
967
968                 warning(_("You appear to have cloned an empty repository."));
969                 mapped_refs = NULL;
970                 our_head_points_at = NULL;
971                 remote_head_points_at = NULL;
972                 remote_head = NULL;
973                 option_no_checkout = 1;
974                 if (!option_bare)
975                         install_branch_config(0, "master", option_origin,
976                                               "refs/heads/master");
977         }
978
979         write_refspec_config(src_ref_prefix, our_head_points_at,
980                         remote_head_points_at, &branch_top);
981
982         if (is_local)
983                 clone_local(path, git_dir);
984         else if (refs && complete_refs_before_fetch)
985                 transport_fetch_refs(transport, mapped_refs);
986
987         update_remote_refs(refs, mapped_refs, remote_head_points_at,
988                            branch_top.buf, reflog_msg.buf, transport, !is_local);
989
990         update_head(our_head_points_at, remote_head, reflog_msg.buf);
991
992         transport_unlock_pack(transport);
993         transport_disconnect(transport);
994
995         junk_mode = JUNK_LEAVE_REPO;
996         err = checkout();
997
998         strbuf_release(&reflog_msg);
999         strbuf_release(&branch_top);
1000         strbuf_release(&key);
1001         strbuf_release(&value);
1002         junk_mode = JUNK_LEAVE_ALL;
1003         return err;
1004 }