Merge branch 'js/fsck-tag-validation'
[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 "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  */
36 static const char * const builtin_clone_usage[] = {
37         N_("git clone [options] [--] <repo> [<dir>]"),
38         NULL
39 };
40
41 static int option_no_checkout, option_bare, option_mirror, option_single_branch = -1;
42 static int option_local = -1, option_no_hardlinks, option_shared, option_recursive;
43 static char *option_template, *option_depth;
44 static char *option_origin = NULL;
45 static char *option_branch = NULL;
46 static const char *real_git_dir;
47 static char *option_upload_pack = "git-upload-pack";
48 static int option_verbosity;
49 static int option_progress = -1;
50 static struct string_list option_config;
51 static struct string_list option_reference;
52
53 static int opt_parse_reference(const struct option *opt, const char *arg, int unset)
54 {
55         struct string_list *option_reference = opt->value;
56         if (!arg)
57                 return -1;
58         string_list_append(option_reference, arg);
59         return 0;
60 }
61
62 static struct option builtin_clone_options[] = {
63         OPT__VERBOSITY(&option_verbosity),
64         OPT_BOOL(0, "progress", &option_progress,
65                  N_("force progress reporting")),
66         OPT_BOOL('n', "no-checkout", &option_no_checkout,
67                  N_("don't create a checkout")),
68         OPT_BOOL(0, "bare", &option_bare, N_("create a bare repository")),
69         OPT_HIDDEN_BOOL(0, "naked", &option_bare,
70                         N_("create a bare repository")),
71         OPT_BOOL(0, "mirror", &option_mirror,
72                  N_("create a mirror repository (implies bare)")),
73         OPT_BOOL('l', "local", &option_local,
74                 N_("to clone from a local repository")),
75         OPT_BOOL(0, "no-hardlinks", &option_no_hardlinks,
76                     N_("don't use local hardlinks, always copy")),
77         OPT_BOOL('s', "shared", &option_shared,
78                     N_("setup as shared repository")),
79         OPT_BOOL(0, "recursive", &option_recursive,
80                     N_("initialize submodules in the clone")),
81         OPT_BOOL(0, "recurse-submodules", &option_recursive,
82                     N_("initialize submodules in the clone")),
83         OPT_STRING(0, "template", &option_template, N_("template-directory"),
84                    N_("directory from which templates will be used")),
85         OPT_CALLBACK(0 , "reference", &option_reference, N_("repo"),
86                      N_("reference repository"), &opt_parse_reference),
87         OPT_STRING('o', "origin", &option_origin, N_("name"),
88                    N_("use <name> instead of 'origin' to track upstream")),
89         OPT_STRING('b', "branch", &option_branch, N_("branch"),
90                    N_("checkout <branch> instead of the remote's HEAD")),
91         OPT_STRING('u', "upload-pack", &option_upload_pack, N_("path"),
92                    N_("path to git-upload-pack on the remote")),
93         OPT_STRING(0, "depth", &option_depth, N_("depth"),
94                     N_("create a shallow clone of that depth")),
95         OPT_BOOL(0, "single-branch", &option_single_branch,
96                     N_("clone only one branch, HEAD or --branch")),
97         OPT_STRING(0, "separate-git-dir", &real_git_dir, N_("gitdir"),
98                    N_("separate git dir from working tree")),
99         OPT_STRING_LIST('c', "config", &option_config, N_("key=value"),
100                         N_("set config inside the new repository")),
101         OPT_END()
102 };
103
104 static const char *argv_submodule[] = {
105         "submodule", "update", "--init", "--recursive", NULL
106 };
107
108 static char *get_repo_path(const char *repo, int *is_bundle)
109 {
110         static char *suffix[] = { "/.git", "", ".git/.git", ".git" };
111         static char *bundle_suffix[] = { ".bundle", "" };
112         struct stat st;
113         int i;
114
115         for (i = 0; i < ARRAY_SIZE(suffix); i++) {
116                 const char *path;
117                 path = mkpath("%s%s", repo, suffix[i]);
118                 if (stat(path, &st))
119                         continue;
120                 if (S_ISDIR(st.st_mode) && is_git_directory(path)) {
121                         *is_bundle = 0;
122                         return xstrdup(absolute_path(path));
123                 } else if (S_ISREG(st.st_mode) && st.st_size > 8) {
124                         /* Is it a "gitfile"? */
125                         char signature[8];
126                         int len, fd = open(path, O_RDONLY);
127                         if (fd < 0)
128                                 continue;
129                         len = read_in_full(fd, signature, 8);
130                         close(fd);
131                         if (len != 8 || strncmp(signature, "gitdir: ", 8))
132                                 continue;
133                         path = read_gitfile(path);
134                         if (path) {
135                                 *is_bundle = 0;
136                                 return xstrdup(absolute_path(path));
137                         }
138                 }
139         }
140
141         for (i = 0; i < ARRAY_SIZE(bundle_suffix); i++) {
142                 const char *path;
143                 path = mkpath("%s%s", repo, bundle_suffix[i]);
144                 if (!stat(path, &st) && S_ISREG(st.st_mode)) {
145                         *is_bundle = 1;
146                         return xstrdup(absolute_path(path));
147                 }
148         }
149
150         return NULL;
151 }
152
153 static char *guess_dir_name(const char *repo, int is_bundle, int is_bare)
154 {
155         const char *end = repo + strlen(repo), *start;
156         char *dir;
157
158         /*
159          * Strip trailing spaces, slashes and /.git
160          */
161         while (repo < end && (is_dir_sep(end[-1]) || isspace(end[-1])))
162                 end--;
163         if (end - repo > 5 && is_dir_sep(end[-5]) &&
164             !strncmp(end - 4, ".git", 4)) {
165                 end -= 5;
166                 while (repo < end && is_dir_sep(end[-1]))
167                         end--;
168         }
169
170         /*
171          * Find last component, but be prepared that repo could have
172          * the form  "remote.example.com:foo.git", i.e. no slash
173          * in the directory part.
174          */
175         start = end;
176         while (repo < start && !is_dir_sep(start[-1]) && start[-1] != ':')
177                 start--;
178
179         /*
180          * Strip .{bundle,git}.
181          */
182         if (is_bundle) {
183                 if (end - start > 7 && !strncmp(end - 7, ".bundle", 7))
184                         end -= 7;
185         } else {
186                 if (end - start > 4 && !strncmp(end - 4, ".git", 4))
187                         end -= 4;
188         }
189
190         if (is_bare) {
191                 struct strbuf result = STRBUF_INIT;
192                 strbuf_addf(&result, "%.*s.git", (int)(end - start), start);
193                 dir = strbuf_detach(&result, NULL);
194         } else
195                 dir = xstrndup(start, end - start);
196         /*
197          * Replace sequences of 'control' characters and whitespace
198          * with one ascii space, remove leading and trailing spaces.
199          */
200         if (*dir) {
201                 char *out = dir;
202                 int prev_space = 1 /* strip leading whitespace */;
203                 for (end = dir; *end; ++end) {
204                         char ch = *end;
205                         if ((unsigned char)ch < '\x20')
206                                 ch = '\x20';
207                         if (isspace(ch)) {
208                                 if (prev_space)
209                                         continue;
210                                 prev_space = 1;
211                         } else
212                                 prev_space = 0;
213                         *out++ = ch;
214                 }
215                 *out = '\0';
216                 if (out > dir && prev_space)
217                         out[-1] = '\0';
218         }
219         return dir;
220 }
221
222 static void strip_trailing_slashes(char *dir)
223 {
224         char *end = dir + strlen(dir);
225
226         while (dir < end - 1 && is_dir_sep(end[-1]))
227                 end--;
228         *end = '\0';
229 }
230
231 static int add_one_reference(struct string_list_item *item, void *cb_data)
232 {
233         char *ref_git;
234         const char *repo;
235         struct strbuf alternate = STRBUF_INIT;
236
237         /* Beware: read_gitfile(), real_path() and mkpath() return static buffer */
238         ref_git = xstrdup(real_path(item->string));
239
240         repo = read_gitfile(ref_git);
241         if (!repo)
242                 repo = read_gitfile(mkpath("%s/.git", ref_git));
243         if (repo) {
244                 free(ref_git);
245                 ref_git = xstrdup(repo);
246         }
247
248         if (!repo && is_directory(mkpath("%s/.git/objects", ref_git))) {
249                 char *ref_git_git = mkpathdup("%s/.git", ref_git);
250                 free(ref_git);
251                 ref_git = ref_git_git;
252         } else if (!is_directory(mkpath("%s/objects", ref_git)))
253                 die(_("reference repository '%s' is not a local repository."),
254                     item->string);
255
256         if (!access(mkpath("%s/shallow", ref_git), F_OK))
257                 die(_("reference repository '%s' is shallow"), item->string);
258
259         if (!access(mkpath("%s/info/grafts", ref_git), F_OK))
260                 die(_("reference repository '%s' is grafted"), item->string);
261
262         strbuf_addf(&alternate, "%s/objects", ref_git);
263         add_to_alternates_file(alternate.buf);
264         strbuf_release(&alternate);
265         free(ref_git);
266         return 0;
267 }
268
269 static void setup_reference(void)
270 {
271         for_each_string_list(&option_reference, add_one_reference, NULL);
272 }
273
274 static void copy_alternates(struct strbuf *src, struct strbuf *dst,
275                             const char *src_repo)
276 {
277         /*
278          * Read from the source objects/info/alternates file
279          * and copy the entries to corresponding file in the
280          * destination repository with add_to_alternates_file().
281          * Both src and dst have "$path/objects/info/alternates".
282          *
283          * Instead of copying bit-for-bit from the original,
284          * we need to append to existing one so that the already
285          * created entry via "clone -s" is not lost, and also
286          * to turn entries with paths relative to the original
287          * absolute, so that they can be used in the new repository.
288          */
289         FILE *in = fopen(src->buf, "r");
290         struct strbuf line = STRBUF_INIT;
291
292         while (strbuf_getline(&line, in, '\n') != EOF) {
293                 char *abs_path, abs_buf[PATH_MAX];
294                 if (!line.len || line.buf[0] == '#')
295                         continue;
296                 if (is_absolute_path(line.buf)) {
297                         add_to_alternates_file(line.buf);
298                         continue;
299                 }
300                 abs_path = mkpath("%s/objects/%s", src_repo, line.buf);
301                 normalize_path_copy(abs_buf, abs_path);
302                 add_to_alternates_file(abs_buf);
303         }
304         strbuf_release(&line);
305         fclose(in);
306 }
307
308 static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
309                                    const char *src_repo, int src_baselen)
310 {
311         struct dirent *de;
312         struct stat buf;
313         int src_len, dest_len;
314         DIR *dir;
315
316         dir = opendir(src->buf);
317         if (!dir)
318                 die_errno(_("failed to open '%s'"), src->buf);
319
320         if (mkdir(dest->buf, 0777)) {
321                 if (errno != EEXIST)
322                         die_errno(_("failed to create directory '%s'"), dest->buf);
323                 else if (stat(dest->buf, &buf))
324                         die_errno(_("failed to stat '%s'"), dest->buf);
325                 else if (!S_ISDIR(buf.st_mode))
326                         die(_("%s exists and is not a directory"), dest->buf);
327         }
328
329         strbuf_addch(src, '/');
330         src_len = src->len;
331         strbuf_addch(dest, '/');
332         dest_len = dest->len;
333
334         while ((de = readdir(dir)) != NULL) {
335                 strbuf_setlen(src, src_len);
336                 strbuf_addstr(src, de->d_name);
337                 strbuf_setlen(dest, dest_len);
338                 strbuf_addstr(dest, de->d_name);
339                 if (stat(src->buf, &buf)) {
340                         warning (_("failed to stat %s\n"), src->buf);
341                         continue;
342                 }
343                 if (S_ISDIR(buf.st_mode)) {
344                         if (de->d_name[0] != '.')
345                                 copy_or_link_directory(src, dest,
346                                                        src_repo, src_baselen);
347                         continue;
348                 }
349
350                 /* Files that cannot be copied bit-for-bit... */
351                 if (!strcmp(src->buf + src_baselen, "/info/alternates")) {
352                         copy_alternates(src, dest, src_repo);
353                         continue;
354                 }
355
356                 if (unlink(dest->buf) && errno != ENOENT)
357                         die_errno(_("failed to unlink '%s'"), dest->buf);
358                 if (!option_no_hardlinks) {
359                         if (!link(src->buf, dest->buf))
360                                 continue;
361                         if (option_local > 0)
362                                 die_errno(_("failed to create link '%s'"), dest->buf);
363                         option_no_hardlinks = 1;
364                 }
365                 if (copy_file_with_time(dest->buf, src->buf, 0666))
366                         die_errno(_("failed to copy file to '%s'"), dest->buf);
367         }
368         closedir(dir);
369 }
370
371 static void clone_local(const char *src_repo, const char *dest_repo)
372 {
373         if (option_shared) {
374                 struct strbuf alt = STRBUF_INIT;
375                 strbuf_addf(&alt, "%s/objects", src_repo);
376                 add_to_alternates_file(alt.buf);
377                 strbuf_release(&alt);
378         } else {
379                 struct strbuf src = STRBUF_INIT;
380                 struct strbuf dest = STRBUF_INIT;
381                 strbuf_addf(&src, "%s/objects", src_repo);
382                 strbuf_addf(&dest, "%s/objects", dest_repo);
383                 copy_or_link_directory(&src, &dest, src_repo, src.len);
384                 strbuf_release(&src);
385                 strbuf_release(&dest);
386         }
387
388         if (0 <= option_verbosity)
389                 fprintf(stderr, _("done.\n"));
390 }
391
392 static const char *junk_work_tree;
393 static const char *junk_git_dir;
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 (junk_git_dir) {
421                 strbuf_addstr(&sb, junk_git_dir);
422                 remove_dir_recursively(&sb, 0);
423                 strbuf_reset(&sb);
424         }
425         if (junk_work_tree) {
426                 strbuf_addstr(&sb, junk_work_tree);
427                 remove_dir_recursively(&sb, 0);
428                 strbuf_reset(&sb);
429         }
430 }
431
432 static void remove_junk_on_signal(int signo)
433 {
434         remove_junk();
435         sigchain_pop(signo);
436         raise(signo);
437 }
438
439 static struct ref *find_remote_branch(const struct ref *refs, const char *branch)
440 {
441         struct ref *ref;
442         struct strbuf head = STRBUF_INIT;
443         strbuf_addstr(&head, "refs/heads/");
444         strbuf_addstr(&head, branch);
445         ref = find_ref_by_name(refs, head.buf);
446         strbuf_release(&head);
447
448         if (ref)
449                 return ref;
450
451         strbuf_addstr(&head, "refs/tags/");
452         strbuf_addstr(&head, branch);
453         ref = find_ref_by_name(refs, head.buf);
454         strbuf_release(&head);
455
456         return ref;
457 }
458
459 static struct ref *wanted_peer_refs(const struct ref *refs,
460                 struct refspec *refspec)
461 {
462         struct ref *head = copy_ref(find_ref_by_name(refs, "HEAD"));
463         struct ref *local_refs = head;
464         struct ref **tail = head ? &head->next : &local_refs;
465
466         if (option_single_branch) {
467                 struct ref *remote_head = NULL;
468
469                 if (!option_branch)
470                         remote_head = guess_remote_head(head, refs, 0);
471                 else {
472                         local_refs = NULL;
473                         tail = &local_refs;
474                         remote_head = copy_ref(find_remote_branch(refs, option_branch));
475                 }
476
477                 if (!remote_head && option_branch)
478                         warning(_("Could not find remote branch %s to clone."),
479                                 option_branch);
480                 else {
481                         get_fetch_map(remote_head, refspec, &tail, 0);
482
483                         /* if --branch=tag, pull the requested tag explicitly */
484                         get_fetch_map(remote_head, tag_refspec, &tail, 0);
485                 }
486         } else
487                 get_fetch_map(refs, refspec, &tail, 0);
488
489         if (!option_mirror && !option_single_branch)
490                 get_fetch_map(refs, tag_refspec, &tail, 0);
491
492         return local_refs;
493 }
494
495 static void write_remote_refs(const struct ref *local_refs)
496 {
497         const struct ref *r;
498
499         lock_packed_refs(LOCK_DIE_ON_ERROR);
500
501         for (r = local_refs; r; r = r->next) {
502                 if (!r->peer_ref)
503                         continue;
504                 add_packed_ref(r->peer_ref->name, r->old_sha1);
505         }
506
507         if (commit_packed_refs())
508                 die_errno("unable to overwrite old ref-pack file");
509 }
510
511 static void write_followtags(const struct ref *refs, const char *msg)
512 {
513         const struct ref *ref;
514         for (ref = refs; ref; ref = ref->next) {
515                 if (!starts_with(ref->name, "refs/tags/"))
516                         continue;
517                 if (ends_with(ref->name, "^{}"))
518                         continue;
519                 if (!has_sha1_file(ref->old_sha1))
520                         continue;
521                 update_ref(msg, ref->name, ref->old_sha1,
522                            NULL, 0, UPDATE_REFS_DIE_ON_ERR);
523         }
524 }
525
526 static int iterate_ref_map(void *cb_data, unsigned char sha1[20])
527 {
528         struct ref **rm = cb_data;
529         struct ref *ref = *rm;
530
531         /*
532          * Skip anything missing a peer_ref, which we are not
533          * actually going to write a ref for.
534          */
535         while (ref && !ref->peer_ref)
536                 ref = ref->next;
537         /* Returning -1 notes "end of list" to the caller. */
538         if (!ref)
539                 return -1;
540
541         hashcpy(sha1, ref->old_sha1);
542         *rm = ref->next;
543         return 0;
544 }
545
546 static void update_remote_refs(const struct ref *refs,
547                                const struct ref *mapped_refs,
548                                const struct ref *remote_head_points_at,
549                                const char *branch_top,
550                                const char *msg,
551                                struct transport *transport,
552                                int check_connectivity)
553 {
554         const struct ref *rm = mapped_refs;
555
556         if (check_connectivity) {
557                 if (transport->progress)
558                         fprintf(stderr, _("Checking connectivity... "));
559                 if (check_everything_connected_with_transport(iterate_ref_map,
560                                                               0, &rm, transport))
561                         die(_("remote did not send all necessary objects"));
562                 if (transport->progress)
563                         fprintf(stderr, _("done.\n"));
564         }
565
566         if (refs) {
567                 write_remote_refs(mapped_refs);
568                 if (option_single_branch)
569                         write_followtags(refs, msg);
570         }
571
572         if (remote_head_points_at && !option_bare) {
573                 struct strbuf head_ref = STRBUF_INIT;
574                 strbuf_addstr(&head_ref, branch_top);
575                 strbuf_addstr(&head_ref, "HEAD");
576                 create_symref(head_ref.buf,
577                               remote_head_points_at->peer_ref->name,
578                               msg);
579         }
580 }
581
582 static void update_head(const struct ref *our, const struct ref *remote,
583                         const char *msg)
584 {
585         const char *head;
586         if (our && skip_prefix(our->name, "refs/heads/", &head)) {
587                 /* Local default branch link */
588                 create_symref("HEAD", our->name, NULL);
589                 if (!option_bare) {
590                         update_ref(msg, "HEAD", our->old_sha1, NULL, 0,
591                                    UPDATE_REFS_DIE_ON_ERR);
592                         install_branch_config(0, head, option_origin, our->name);
593                 }
594         } else if (our) {
595                 struct commit *c = lookup_commit_reference(our->old_sha1);
596                 /* --branch specifies a non-branch (i.e. tags), detach HEAD */
597                 update_ref(msg, "HEAD", c->object.sha1,
598                            NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
599         } else if (remote) {
600                 /*
601                  * We know remote HEAD points to a non-branch, or
602                  * HEAD points to a branch but we don't know which one.
603                  * Detach HEAD in all these cases.
604                  */
605                 update_ref(msg, "HEAD", remote->old_sha1,
606                            NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
607         }
608 }
609
610 static int checkout(void)
611 {
612         unsigned char sha1[20];
613         char *head;
614         struct lock_file *lock_file;
615         struct unpack_trees_options opts;
616         struct tree *tree;
617         struct tree_desc t;
618         int err = 0;
619
620         if (option_no_checkout)
621                 return 0;
622
623         head = resolve_refdup("HEAD", RESOLVE_REF_READING, sha1, NULL);
624         if (!head) {
625                 warning(_("remote HEAD refers to nonexistent ref, "
626                           "unable to checkout.\n"));
627                 return 0;
628         }
629         if (!strcmp(head, "HEAD")) {
630                 if (advice_detached_head)
631                         detach_advice(sha1_to_hex(sha1));
632         } else {
633                 if (!starts_with(head, "refs/heads/"))
634                         die(_("HEAD not found below refs/heads!"));
635         }
636         free(head);
637
638         /* We need to be in the new work tree for the checkout */
639         setup_work_tree();
640
641         lock_file = xcalloc(1, sizeof(struct lock_file));
642         hold_locked_index(lock_file, 1);
643
644         memset(&opts, 0, sizeof opts);
645         opts.update = 1;
646         opts.merge = 1;
647         opts.fn = oneway_merge;
648         opts.verbose_update = (option_verbosity >= 0);
649         opts.src_index = &the_index;
650         opts.dst_index = &the_index;
651
652         tree = parse_tree_indirect(sha1);
653         parse_tree(tree);
654         init_tree_desc(&t, tree->buffer, tree->size);
655         if (unpack_trees(1, &t, &opts) < 0)
656                 die(_("unable to checkout working tree"));
657
658         if (write_locked_index(&the_index, lock_file, COMMIT_LOCK))
659                 die(_("unable to write new index file"));
660
661         err |= run_hook_le(NULL, "post-checkout", sha1_to_hex(null_sha1),
662                            sha1_to_hex(sha1), "1", NULL);
663
664         if (!err && option_recursive)
665                 err = run_command_v_opt(argv_submodule, RUN_GIT_CMD);
666
667         return err;
668 }
669
670 static int write_one_config(const char *key, const char *value, void *data)
671 {
672         return git_config_set_multivar(key, value ? value : "true", "^$", 0);
673 }
674
675 static void write_config(struct string_list *config)
676 {
677         int i;
678
679         for (i = 0; i < config->nr; i++) {
680                 if (git_config_parse_parameter(config->items[i].string,
681                                                write_one_config, NULL) < 0)
682                         die("unable to write parameters to config file");
683         }
684 }
685
686 static void write_refspec_config(const char *src_ref_prefix,
687                 const struct ref *our_head_points_at,
688                 const struct ref *remote_head_points_at,
689                 struct strbuf *branch_top)
690 {
691         struct strbuf key = STRBUF_INIT;
692         struct strbuf value = STRBUF_INIT;
693
694         if (option_mirror || !option_bare) {
695                 if (option_single_branch && !option_mirror) {
696                         if (option_branch) {
697                                 if (starts_with(our_head_points_at->name, "refs/tags/"))
698                                         strbuf_addf(&value, "+%s:%s", our_head_points_at->name,
699                                                 our_head_points_at->name);
700                                 else
701                                         strbuf_addf(&value, "+%s:%s%s", our_head_points_at->name,
702                                                 branch_top->buf, option_branch);
703                         } else if (remote_head_points_at) {
704                                 const char *head = remote_head_points_at->name;
705                                 if (!skip_prefix(head, "refs/heads/", &head))
706                                         die("BUG: remote HEAD points at non-head?");
707
708                                 strbuf_addf(&value, "+%s:%s%s", remote_head_points_at->name,
709                                                 branch_top->buf, head);
710                         }
711                         /*
712                          * otherwise, the next "git fetch" will
713                          * simply fetch from HEAD without updating
714                          * any remote-tracking branch, which is what
715                          * we want.
716                          */
717                 } else {
718                         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top->buf);
719                 }
720                 /* Configure the remote */
721                 if (value.len) {
722                         strbuf_addf(&key, "remote.%s.fetch", option_origin);
723                         git_config_set_multivar(key.buf, value.buf, "^$", 0);
724                         strbuf_reset(&key);
725
726                         if (option_mirror) {
727                                 strbuf_addf(&key, "remote.%s.mirror", option_origin);
728                                 git_config_set(key.buf, "true");
729                                 strbuf_reset(&key);
730                         }
731                 }
732         }
733
734         strbuf_release(&key);
735         strbuf_release(&value);
736 }
737
738 int cmd_clone(int argc, const char **argv, const char *prefix)
739 {
740         int is_bundle = 0, is_local;
741         struct stat buf;
742         const char *repo_name, *repo, *work_tree, *git_dir;
743         char *path, *dir;
744         int dest_exists;
745         const struct ref *refs, *remote_head;
746         const struct ref *remote_head_points_at;
747         const struct ref *our_head_points_at;
748         struct ref *mapped_refs;
749         const struct ref *ref;
750         struct strbuf key = STRBUF_INIT, value = STRBUF_INIT;
751         struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
752         struct transport *transport = NULL;
753         const char *src_ref_prefix = "refs/heads/";
754         struct remote *remote;
755         int err = 0, complete_refs_before_fetch = 1;
756
757         struct refspec *refspec;
758         const char *fetch_pattern;
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
800         /* no need to be strict, transport_set_option() will validate it again */
801         if (option_depth && atoi(option_depth) < 1)
802                 die(_("depth %s is not a positive number"), option_depth);
803
804         if (argc == 2)
805                 dir = xstrdup(argv[1]);
806         else
807                 dir = guess_dir_name(repo_name, is_bundle, option_bare);
808         strip_trailing_slashes(dir);
809
810         dest_exists = !stat(dir, &buf);
811         if (dest_exists && !is_empty_dir(dir))
812                 die(_("destination path '%s' already exists and is not "
813                         "an empty directory."), dir);
814
815         strbuf_addf(&reflog_msg, "clone: from %s", repo);
816
817         if (option_bare)
818                 work_tree = NULL;
819         else {
820                 work_tree = getenv("GIT_WORK_TREE");
821                 if (work_tree && !stat(work_tree, &buf))
822                         die(_("working tree '%s' already exists."), work_tree);
823         }
824
825         if (option_bare || work_tree)
826                 git_dir = xstrdup(dir);
827         else {
828                 work_tree = dir;
829                 git_dir = mkpathdup("%s/.git", dir);
830         }
831
832         if (!option_bare) {
833                 junk_work_tree = work_tree;
834                 if (safe_create_leading_directories_const(work_tree) < 0)
835                         die_errno(_("could not create leading directories of '%s'"),
836                                   work_tree);
837                 if (!dest_exists && mkdir(work_tree, 0777))
838                         die_errno(_("could not create work tree dir '%s'."),
839                                   work_tree);
840                 set_git_work_tree(work_tree);
841         }
842         junk_git_dir = git_dir;
843         atexit(remove_junk);
844         sigchain_push_common(remove_junk_on_signal);
845
846         if (safe_create_leading_directories_const(git_dir) < 0)
847                 die(_("could not create leading directories of '%s'"), git_dir);
848
849         set_git_dir_init(git_dir, real_git_dir, 0);
850         if (real_git_dir) {
851                 git_dir = real_git_dir;
852                 junk_git_dir = real_git_dir;
853         }
854
855         if (0 <= option_verbosity) {
856                 if (option_bare)
857                         fprintf(stderr, _("Cloning into bare repository '%s'...\n"), dir);
858                 else
859                         fprintf(stderr, _("Cloning into '%s'...\n"), dir);
860         }
861         init_db(option_template, INIT_DB_QUIET);
862         write_config(&option_config);
863
864         git_config(git_default_config, NULL);
865
866         if (option_bare) {
867                 if (option_mirror)
868                         src_ref_prefix = "refs/";
869                 strbuf_addstr(&branch_top, src_ref_prefix);
870
871                 git_config_set("core.bare", "true");
872         } else {
873                 strbuf_addf(&branch_top, "refs/remotes/%s/", option_origin);
874         }
875
876         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top.buf);
877         strbuf_addf(&key, "remote.%s.url", option_origin);
878         git_config_set(key.buf, repo);
879         strbuf_reset(&key);
880
881         if (option_reference.nr)
882                 setup_reference();
883
884         fetch_pattern = value.buf;
885         refspec = parse_fetch_refspec(1, &fetch_pattern);
886
887         strbuf_reset(&value);
888
889         remote = remote_get(option_origin);
890         transport = transport_get(remote, remote->url[0]);
891         path = get_repo_path(remote->url[0], &is_bundle);
892         is_local = option_local != 0 && path && !is_bundle;
893         if (is_local) {
894                 if (option_depth)
895                         warning(_("--depth is ignored in local clones; use file:// instead."));
896                 if (!access(mkpath("%s/shallow", path), F_OK)) {
897                         if (option_local > 0)
898                                 warning(_("source repository is shallow, ignoring --local"));
899                         is_local = 0;
900                 }
901         }
902         if (option_local > 0 && !is_local)
903                 warning(_("--local is ignored"));
904         transport->cloning = 1;
905
906         if (!transport->get_refs_list || (!is_local && !transport->fetch))
907                 die(_("Don't know how to clone %s"), transport->url);
908
909         transport_set_option(transport, TRANS_OPT_KEEP, "yes");
910
911         if (option_depth)
912                 transport_set_option(transport, TRANS_OPT_DEPTH,
913                                      option_depth);
914         if (option_single_branch)
915                 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
916
917         transport_set_verbosity(transport, option_verbosity, option_progress);
918
919         if (option_upload_pack)
920                 transport_set_option(transport, TRANS_OPT_UPLOADPACK,
921                                      option_upload_pack);
922
923         if (transport->smart_options && !option_depth)
924                 transport->smart_options->check_self_contained_and_connected = 1;
925
926         refs = transport_get_remote_refs(transport);
927
928         if (refs) {
929                 mapped_refs = wanted_peer_refs(refs, refspec);
930                 /*
931                  * transport_get_remote_refs() may return refs with null sha-1
932                  * in mapped_refs (see struct transport->get_refs_list
933                  * comment). In that case we need fetch it early because
934                  * remote_head code below relies on it.
935                  *
936                  * for normal clones, transport_get_remote_refs() should
937                  * return reliable ref set, we can delay cloning until after
938                  * remote HEAD check.
939                  */
940                 for (ref = refs; ref; ref = ref->next)
941                         if (is_null_sha1(ref->old_sha1)) {
942                                 complete_refs_before_fetch = 0;
943                                 break;
944                         }
945
946                 if (!is_local && !complete_refs_before_fetch)
947                         transport_fetch_refs(transport, mapped_refs);
948
949                 remote_head = find_ref_by_name(refs, "HEAD");
950                 remote_head_points_at =
951                         guess_remote_head(remote_head, mapped_refs, 0);
952
953                 if (option_branch) {
954                         our_head_points_at =
955                                 find_remote_branch(mapped_refs, option_branch);
956
957                         if (!our_head_points_at)
958                                 die(_("Remote branch %s not found in upstream %s"),
959                                     option_branch, option_origin);
960                 }
961                 else
962                         our_head_points_at = remote_head_points_at;
963         }
964         else {
965                 if (option_branch)
966                         die(_("Remote branch %s not found in upstream %s"),
967                                         option_branch, option_origin);
968
969                 warning(_("You appear to have cloned an empty repository."));
970                 mapped_refs = NULL;
971                 our_head_points_at = NULL;
972                 remote_head_points_at = NULL;
973                 remote_head = NULL;
974                 option_no_checkout = 1;
975                 if (!option_bare)
976                         install_branch_config(0, "master", option_origin,
977                                               "refs/heads/master");
978         }
979
980         write_refspec_config(src_ref_prefix, our_head_points_at,
981                         remote_head_points_at, &branch_top);
982
983         if (is_local)
984                 clone_local(path, git_dir);
985         else if (refs && complete_refs_before_fetch)
986                 transport_fetch_refs(transport, mapped_refs);
987
988         update_remote_refs(refs, mapped_refs, remote_head_points_at,
989                            branch_top.buf, reflog_msg.buf, transport, !is_local);
990
991         update_head(our_head_points_at, remote_head, reflog_msg.buf);
992
993         transport_unlock_pack(transport);
994         transport_disconnect(transport);
995
996         junk_mode = JUNK_LEAVE_REPO;
997         err = checkout();
998
999         strbuf_release(&reflog_msg);
1000         strbuf_release(&branch_top);
1001         strbuf_release(&key);
1002         strbuf_release(&value);
1003         junk_mode = JUNK_LEAVE_ALL;
1004
1005         free(refspec);
1006         return err;
1007 }