Merge branch 'mg/log-decorate-HEAD'
[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 static int option_dissociate;
53
54 static int opt_parse_reference(const struct option *opt, const char *arg, int unset)
55 {
56         struct string_list *option_reference = opt->value;
57         if (!arg)
58                 return -1;
59         string_list_append(option_reference, arg);
60         return 0;
61 }
62
63 static struct option builtin_clone_options[] = {
64         OPT__VERBOSITY(&option_verbosity),
65         OPT_BOOL(0, "progress", &option_progress,
66                  N_("force progress reporting")),
67         OPT_BOOL('n', "no-checkout", &option_no_checkout,
68                  N_("don't create a checkout")),
69         OPT_BOOL(0, "bare", &option_bare, N_("create a bare repository")),
70         OPT_HIDDEN_BOOL(0, "naked", &option_bare,
71                         N_("create a bare repository")),
72         OPT_BOOL(0, "mirror", &option_mirror,
73                  N_("create a mirror repository (implies bare)")),
74         OPT_BOOL('l', "local", &option_local,
75                 N_("to clone from a local repository")),
76         OPT_BOOL(0, "no-hardlinks", &option_no_hardlinks,
77                     N_("don't use local hardlinks, always copy")),
78         OPT_BOOL('s', "shared", &option_shared,
79                     N_("setup as shared repository")),
80         OPT_BOOL(0, "recursive", &option_recursive,
81                     N_("initialize submodules in the clone")),
82         OPT_BOOL(0, "recurse-submodules", &option_recursive,
83                     N_("initialize submodules in the clone")),
84         OPT_STRING(0, "template", &option_template, N_("template-directory"),
85                    N_("directory from which templates will be used")),
86         OPT_CALLBACK(0 , "reference", &option_reference, N_("repo"),
87                      N_("reference repository"), &opt_parse_reference),
88         OPT_STRING('o', "origin", &option_origin, N_("name"),
89                    N_("use <name> instead of 'origin' to track upstream")),
90         OPT_STRING('b', "branch", &option_branch, N_("branch"),
91                    N_("checkout <branch> instead of the remote's HEAD")),
92         OPT_STRING('u', "upload-pack", &option_upload_pack, N_("path"),
93                    N_("path to git-upload-pack on the remote")),
94         OPT_STRING(0, "depth", &option_depth, N_("depth"),
95                     N_("create a shallow clone of that depth")),
96         OPT_BOOL(0, "single-branch", &option_single_branch,
97                     N_("clone only one branch, HEAD or --branch")),
98         OPT_BOOL(0, "dissociate", &option_dissociate,
99                  N_("use --reference only while cloning")),
100         OPT_STRING(0, "separate-git-dir", &real_git_dir, N_("gitdir"),
101                    N_("separate git dir from working tree")),
102         OPT_STRING_LIST('c', "config", &option_config, N_("key=value"),
103                         N_("set config inside the new repository")),
104         OPT_END()
105 };
106
107 static const char *argv_submodule[] = {
108         "submodule", "update", "--init", "--recursive", NULL
109 };
110
111 static char *get_repo_path(const char *repo, int *is_bundle)
112 {
113         static char *suffix[] = { "/.git", "", ".git/.git", ".git" };
114         static char *bundle_suffix[] = { ".bundle", "" };
115         struct stat st;
116         int i;
117
118         for (i = 0; i < ARRAY_SIZE(suffix); i++) {
119                 const char *path;
120                 path = mkpath("%s%s", repo, suffix[i]);
121                 if (stat(path, &st))
122                         continue;
123                 if (S_ISDIR(st.st_mode) && is_git_directory(path)) {
124                         *is_bundle = 0;
125                         return xstrdup(absolute_path(path));
126                 } else if (S_ISREG(st.st_mode) && st.st_size > 8) {
127                         /* Is it a "gitfile"? */
128                         char signature[8];
129                         int len, fd = open(path, 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                         path = read_gitfile(path);
137                         if (path) {
138                                 *is_bundle = 0;
139                                 return xstrdup(absolute_path(path));
140                         }
141                 }
142         }
143
144         for (i = 0; i < ARRAY_SIZE(bundle_suffix); i++) {
145                 const char *path;
146                 path = mkpath("%s%s", repo, bundle_suffix[i]);
147                 if (!stat(path, &st) && S_ISREG(st.st_mode)) {
148                         *is_bundle = 1;
149                         return xstrdup(absolute_path(path));
150                 }
151         }
152
153         return NULL;
154 }
155
156 static char *guess_dir_name(const char *repo, int is_bundle, int is_bare)
157 {
158         const char *end = repo + strlen(repo), *start;
159         char *dir;
160
161         /*
162          * Strip trailing spaces, slashes and /.git
163          */
164         while (repo < end && (is_dir_sep(end[-1]) || isspace(end[-1])))
165                 end--;
166         if (end - repo > 5 && is_dir_sep(end[-5]) &&
167             !strncmp(end - 4, ".git", 4)) {
168                 end -= 5;
169                 while (repo < end && is_dir_sep(end[-1]))
170                         end--;
171         }
172
173         /*
174          * Find last component, but be prepared that repo could have
175          * the form  "remote.example.com:foo.git", i.e. no slash
176          * in the directory part.
177          */
178         start = end;
179         while (repo < start && !is_dir_sep(start[-1]) && start[-1] != ':')
180                 start--;
181
182         /*
183          * Strip .{bundle,git}.
184          */
185         if (is_bundle) {
186                 if (end - start > 7 && !strncmp(end - 7, ".bundle", 7))
187                         end -= 7;
188         } else {
189                 if (end - start > 4 && !strncmp(end - 4, ".git", 4))
190                         end -= 4;
191         }
192
193         if (is_bare) {
194                 struct strbuf result = STRBUF_INIT;
195                 strbuf_addf(&result, "%.*s.git", (int)(end - start), start);
196                 dir = strbuf_detach(&result, NULL);
197         } else
198                 dir = xstrndup(start, end - start);
199         /*
200          * Replace sequences of 'control' characters and whitespace
201          * with one ascii space, remove leading and trailing spaces.
202          */
203         if (*dir) {
204                 char *out = dir;
205                 int prev_space = 1 /* strip leading whitespace */;
206                 for (end = dir; *end; ++end) {
207                         char ch = *end;
208                         if ((unsigned char)ch < '\x20')
209                                 ch = '\x20';
210                         if (isspace(ch)) {
211                                 if (prev_space)
212                                         continue;
213                                 prev_space = 1;
214                         } else
215                                 prev_space = 0;
216                         *out++ = ch;
217                 }
218                 *out = '\0';
219                 if (out > dir && prev_space)
220                         out[-1] = '\0';
221         }
222         return dir;
223 }
224
225 static void strip_trailing_slashes(char *dir)
226 {
227         char *end = dir + strlen(dir);
228
229         while (dir < end - 1 && is_dir_sep(end[-1]))
230                 end--;
231         *end = '\0';
232 }
233
234 static int add_one_reference(struct string_list_item *item, void *cb_data)
235 {
236         char *ref_git;
237         const char *repo;
238         struct strbuf alternate = STRBUF_INIT;
239
240         /* Beware: read_gitfile(), real_path() and mkpath() return static buffer */
241         ref_git = xstrdup(real_path(item->string));
242
243         repo = read_gitfile(ref_git);
244         if (!repo)
245                 repo = read_gitfile(mkpath("%s/.git", ref_git));
246         if (repo) {
247                 free(ref_git);
248                 ref_git = xstrdup(repo);
249         }
250
251         if (!repo && is_directory(mkpath("%s/.git/objects", ref_git))) {
252                 char *ref_git_git = mkpathdup("%s/.git", ref_git);
253                 free(ref_git);
254                 ref_git = ref_git_git;
255         } else if (!is_directory(mkpath("%s/objects", ref_git)))
256                 die(_("reference repository '%s' is not a local repository."),
257                     item->string);
258
259         if (!access(mkpath("%s/shallow", ref_git), F_OK))
260                 die(_("reference repository '%s' is shallow"), item->string);
261
262         if (!access(mkpath("%s/info/grafts", ref_git), F_OK))
263                 die(_("reference repository '%s' is grafted"), item->string);
264
265         strbuf_addf(&alternate, "%s/objects", ref_git);
266         add_to_alternates_file(alternate.buf);
267         strbuf_release(&alternate);
268         free(ref_git);
269         return 0;
270 }
271
272 static void setup_reference(void)
273 {
274         for_each_string_list(&option_reference, add_one_reference, NULL);
275 }
276
277 static void copy_alternates(struct strbuf *src, struct strbuf *dst,
278                             const char *src_repo)
279 {
280         /*
281          * Read from the source objects/info/alternates file
282          * and copy the entries to corresponding file in the
283          * destination repository with add_to_alternates_file().
284          * Both src and dst have "$path/objects/info/alternates".
285          *
286          * Instead of copying bit-for-bit from the original,
287          * we need to append to existing one so that the already
288          * created entry via "clone -s" is not lost, and also
289          * to turn entries with paths relative to the original
290          * absolute, so that they can be used in the new repository.
291          */
292         FILE *in = fopen(src->buf, "r");
293         struct strbuf line = STRBUF_INIT;
294
295         while (strbuf_getline(&line, in, '\n') != EOF) {
296                 char *abs_path;
297                 if (!line.len || line.buf[0] == '#')
298                         continue;
299                 if (is_absolute_path(line.buf)) {
300                         add_to_alternates_file(line.buf);
301                         continue;
302                 }
303                 abs_path = mkpathdup("%s/objects/%s", src_repo, line.buf);
304                 normalize_path_copy(abs_path, abs_path);
305                 add_to_alternates_file(abs_path);
306                 free(abs_path);
307         }
308         strbuf_release(&line);
309         fclose(in);
310 }
311
312 static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
313                                    const char *src_repo, int src_baselen)
314 {
315         struct dirent *de;
316         struct stat buf;
317         int src_len, dest_len;
318         DIR *dir;
319
320         dir = opendir(src->buf);
321         if (!dir)
322                 die_errno(_("failed to open '%s'"), src->buf);
323
324         if (mkdir(dest->buf, 0777)) {
325                 if (errno != EEXIST)
326                         die_errno(_("failed to create directory '%s'"), dest->buf);
327                 else if (stat(dest->buf, &buf))
328                         die_errno(_("failed to stat '%s'"), dest->buf);
329                 else if (!S_ISDIR(buf.st_mode))
330                         die(_("%s exists and is not a directory"), dest->buf);
331         }
332
333         strbuf_addch(src, '/');
334         src_len = src->len;
335         strbuf_addch(dest, '/');
336         dest_len = dest->len;
337
338         while ((de = readdir(dir)) != NULL) {
339                 strbuf_setlen(src, src_len);
340                 strbuf_addstr(src, de->d_name);
341                 strbuf_setlen(dest, dest_len);
342                 strbuf_addstr(dest, de->d_name);
343                 if (stat(src->buf, &buf)) {
344                         warning (_("failed to stat %s\n"), src->buf);
345                         continue;
346                 }
347                 if (S_ISDIR(buf.st_mode)) {
348                         if (de->d_name[0] != '.')
349                                 copy_or_link_directory(src, dest,
350                                                        src_repo, src_baselen);
351                         continue;
352                 }
353
354                 /* Files that cannot be copied bit-for-bit... */
355                 if (!strcmp(src->buf + src_baselen, "/info/alternates")) {
356                         copy_alternates(src, dest, src_repo);
357                         continue;
358                 }
359
360                 if (unlink(dest->buf) && errno != ENOENT)
361                         die_errno(_("failed to unlink '%s'"), dest->buf);
362                 if (!option_no_hardlinks) {
363                         if (!link(src->buf, dest->buf))
364                                 continue;
365                         if (option_local > 0)
366                                 die_errno(_("failed to create link '%s'"), dest->buf);
367                         option_no_hardlinks = 1;
368                 }
369                 if (copy_file_with_time(dest->buf, src->buf, 0666))
370                         die_errno(_("failed to copy file to '%s'"), dest->buf);
371         }
372         closedir(dir);
373 }
374
375 static void clone_local(const char *src_repo, const char *dest_repo)
376 {
377         if (option_shared) {
378                 struct strbuf alt = STRBUF_INIT;
379                 strbuf_addf(&alt, "%s/objects", src_repo);
380                 add_to_alternates_file(alt.buf);
381                 strbuf_release(&alt);
382         } else {
383                 struct strbuf src = STRBUF_INIT;
384                 struct strbuf dest = STRBUF_INIT;
385                 strbuf_addf(&src, "%s/objects", src_repo);
386                 strbuf_addf(&dest, "%s/objects", dest_repo);
387                 copy_or_link_directory(&src, &dest, src_repo, src.len);
388                 strbuf_release(&src);
389                 strbuf_release(&dest);
390         }
391
392         if (0 <= option_verbosity)
393                 fprintf(stderr, _("done.\n"));
394 }
395
396 static const char *junk_work_tree;
397 static const char *junk_git_dir;
398 static enum {
399         JUNK_LEAVE_NONE,
400         JUNK_LEAVE_REPO,
401         JUNK_LEAVE_ALL
402 } junk_mode = JUNK_LEAVE_NONE;
403
404 static const char junk_leave_repo_msg[] =
405 N_("Clone succeeded, but checkout failed.\n"
406    "You can inspect what was checked out with 'git status'\n"
407    "and retry the checkout with 'git checkout -f HEAD'\n");
408
409 static void remove_junk(void)
410 {
411         struct strbuf sb = STRBUF_INIT;
412
413         switch (junk_mode) {
414         case JUNK_LEAVE_REPO:
415                 warning("%s", _(junk_leave_repo_msg));
416                 /* fall-through */
417         case JUNK_LEAVE_ALL:
418                 return;
419         default:
420                 /* proceed to removal */
421                 break;
422         }
423
424         if (junk_git_dir) {
425                 strbuf_addstr(&sb, junk_git_dir);
426                 remove_dir_recursively(&sb, 0);
427                 strbuf_reset(&sb);
428         }
429         if (junk_work_tree) {
430                 strbuf_addstr(&sb, junk_work_tree);
431                 remove_dir_recursively(&sb, 0);
432                 strbuf_reset(&sb);
433         }
434 }
435
436 static void remove_junk_on_signal(int signo)
437 {
438         remove_junk();
439         sigchain_pop(signo);
440         raise(signo);
441 }
442
443 static struct ref *find_remote_branch(const struct ref *refs, const char *branch)
444 {
445         struct ref *ref;
446         struct strbuf head = STRBUF_INIT;
447         strbuf_addstr(&head, "refs/heads/");
448         strbuf_addstr(&head, branch);
449         ref = find_ref_by_name(refs, head.buf);
450         strbuf_release(&head);
451
452         if (ref)
453                 return ref;
454
455         strbuf_addstr(&head, "refs/tags/");
456         strbuf_addstr(&head, branch);
457         ref = find_ref_by_name(refs, head.buf);
458         strbuf_release(&head);
459
460         return ref;
461 }
462
463 static struct ref *wanted_peer_refs(const struct ref *refs,
464                 struct refspec *refspec)
465 {
466         struct ref *head = copy_ref(find_ref_by_name(refs, "HEAD"));
467         struct ref *local_refs = head;
468         struct ref **tail = head ? &head->next : &local_refs;
469
470         if (option_single_branch) {
471                 struct ref *remote_head = NULL;
472
473                 if (!option_branch)
474                         remote_head = guess_remote_head(head, refs, 0);
475                 else {
476                         local_refs = NULL;
477                         tail = &local_refs;
478                         remote_head = copy_ref(find_remote_branch(refs, option_branch));
479                 }
480
481                 if (!remote_head && option_branch)
482                         warning(_("Could not find remote branch %s to clone."),
483                                 option_branch);
484                 else {
485                         get_fetch_map(remote_head, refspec, &tail, 0);
486
487                         /* if --branch=tag, pull the requested tag explicitly */
488                         get_fetch_map(remote_head, tag_refspec, &tail, 0);
489                 }
490         } else
491                 get_fetch_map(refs, refspec, &tail, 0);
492
493         if (!option_mirror && !option_single_branch)
494                 get_fetch_map(refs, tag_refspec, &tail, 0);
495
496         return local_refs;
497 }
498
499 static void write_remote_refs(const struct ref *local_refs)
500 {
501         const struct ref *r;
502
503         lock_packed_refs(LOCK_DIE_ON_ERROR);
504
505         for (r = local_refs; r; r = r->next) {
506                 if (!r->peer_ref)
507                         continue;
508                 add_packed_ref(r->peer_ref->name, r->old_sha1);
509         }
510
511         if (commit_packed_refs())
512                 die_errno("unable to overwrite old ref-pack file");
513 }
514
515 static void write_followtags(const struct ref *refs, const char *msg)
516 {
517         const struct ref *ref;
518         for (ref = refs; ref; ref = ref->next) {
519                 if (!starts_with(ref->name, "refs/tags/"))
520                         continue;
521                 if (ends_with(ref->name, "^{}"))
522                         continue;
523                 if (!has_sha1_file(ref->old_sha1))
524                         continue;
525                 update_ref(msg, ref->name, ref->old_sha1,
526                            NULL, 0, UPDATE_REFS_DIE_ON_ERR);
527         }
528 }
529
530 static int iterate_ref_map(void *cb_data, unsigned char sha1[20])
531 {
532         struct ref **rm = cb_data;
533         struct ref *ref = *rm;
534
535         /*
536          * Skip anything missing a peer_ref, which we are not
537          * actually going to write a ref for.
538          */
539         while (ref && !ref->peer_ref)
540                 ref = ref->next;
541         /* Returning -1 notes "end of list" to the caller. */
542         if (!ref)
543                 return -1;
544
545         hashcpy(sha1, ref->old_sha1);
546         *rm = ref->next;
547         return 0;
548 }
549
550 static void update_remote_refs(const struct ref *refs,
551                                const struct ref *mapped_refs,
552                                const struct ref *remote_head_points_at,
553                                const char *branch_top,
554                                const char *msg,
555                                struct transport *transport,
556                                int check_connectivity)
557 {
558         const struct ref *rm = mapped_refs;
559
560         if (check_connectivity) {
561                 if (transport->progress)
562                         fprintf(stderr, _("Checking connectivity... "));
563                 if (check_everything_connected_with_transport(iterate_ref_map,
564                                                               0, &rm, transport))
565                         die(_("remote did not send all necessary objects"));
566                 if (transport->progress)
567                         fprintf(stderr, _("done.\n"));
568         }
569
570         if (refs) {
571                 write_remote_refs(mapped_refs);
572                 if (option_single_branch)
573                         write_followtags(refs, msg);
574         }
575
576         if (remote_head_points_at && !option_bare) {
577                 struct strbuf head_ref = STRBUF_INIT;
578                 strbuf_addstr(&head_ref, branch_top);
579                 strbuf_addstr(&head_ref, "HEAD");
580                 create_symref(head_ref.buf,
581                               remote_head_points_at->peer_ref->name,
582                               msg);
583         }
584 }
585
586 static void update_head(const struct ref *our, const struct ref *remote,
587                         const char *msg)
588 {
589         const char *head;
590         if (our && skip_prefix(our->name, "refs/heads/", &head)) {
591                 /* Local default branch link */
592                 create_symref("HEAD", our->name, NULL);
593                 if (!option_bare) {
594                         update_ref(msg, "HEAD", our->old_sha1, NULL, 0,
595                                    UPDATE_REFS_DIE_ON_ERR);
596                         install_branch_config(0, head, option_origin, our->name);
597                 }
598         } else if (our) {
599                 struct commit *c = lookup_commit_reference(our->old_sha1);
600                 /* --branch specifies a non-branch (i.e. tags), detach HEAD */
601                 update_ref(msg, "HEAD", c->object.sha1,
602                            NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
603         } else if (remote) {
604                 /*
605                  * We know remote HEAD points to a non-branch, or
606                  * HEAD points to a branch but we don't know which one.
607                  * Detach HEAD in all these cases.
608                  */
609                 update_ref(msg, "HEAD", remote->old_sha1,
610                            NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
611         }
612 }
613
614 static int checkout(void)
615 {
616         unsigned char sha1[20];
617         char *head;
618         struct lock_file *lock_file;
619         struct unpack_trees_options opts;
620         struct tree *tree;
621         struct tree_desc t;
622         int err = 0;
623
624         if (option_no_checkout)
625                 return 0;
626
627         head = resolve_refdup("HEAD", RESOLVE_REF_READING, sha1, NULL);
628         if (!head) {
629                 warning(_("remote HEAD refers to nonexistent ref, "
630                           "unable to checkout.\n"));
631                 return 0;
632         }
633         if (!strcmp(head, "HEAD")) {
634                 if (advice_detached_head)
635                         detach_advice(sha1_to_hex(sha1));
636         } else {
637                 if (!starts_with(head, "refs/heads/"))
638                         die(_("HEAD not found below refs/heads!"));
639         }
640         free(head);
641
642         /* We need to be in the new work tree for the checkout */
643         setup_work_tree();
644
645         lock_file = xcalloc(1, sizeof(struct lock_file));
646         hold_locked_index(lock_file, 1);
647
648         memset(&opts, 0, sizeof opts);
649         opts.update = 1;
650         opts.merge = 1;
651         opts.fn = oneway_merge;
652         opts.verbose_update = (option_verbosity >= 0);
653         opts.src_index = &the_index;
654         opts.dst_index = &the_index;
655
656         tree = parse_tree_indirect(sha1);
657         parse_tree(tree);
658         init_tree_desc(&t, tree->buffer, tree->size);
659         if (unpack_trees(1, &t, &opts) < 0)
660                 die(_("unable to checkout working tree"));
661
662         if (write_locked_index(&the_index, lock_file, COMMIT_LOCK))
663                 die(_("unable to write new index file"));
664
665         err |= run_hook_le(NULL, "post-checkout", sha1_to_hex(null_sha1),
666                            sha1_to_hex(sha1), "1", NULL);
667
668         if (!err && option_recursive)
669                 err = run_command_v_opt(argv_submodule, RUN_GIT_CMD);
670
671         return err;
672 }
673
674 static int write_one_config(const char *key, const char *value, void *data)
675 {
676         return git_config_set_multivar(key, value ? value : "true", "^$", 0);
677 }
678
679 static void write_config(struct string_list *config)
680 {
681         int i;
682
683         for (i = 0; i < config->nr; i++) {
684                 if (git_config_parse_parameter(config->items[i].string,
685                                                write_one_config, NULL) < 0)
686                         die("unable to write parameters to config file");
687         }
688 }
689
690 static void write_refspec_config(const char *src_ref_prefix,
691                 const struct ref *our_head_points_at,
692                 const struct ref *remote_head_points_at,
693                 struct strbuf *branch_top)
694 {
695         struct strbuf key = STRBUF_INIT;
696         struct strbuf value = STRBUF_INIT;
697
698         if (option_mirror || !option_bare) {
699                 if (option_single_branch && !option_mirror) {
700                         if (option_branch) {
701                                 if (starts_with(our_head_points_at->name, "refs/tags/"))
702                                         strbuf_addf(&value, "+%s:%s", our_head_points_at->name,
703                                                 our_head_points_at->name);
704                                 else
705                                         strbuf_addf(&value, "+%s:%s%s", our_head_points_at->name,
706                                                 branch_top->buf, option_branch);
707                         } else if (remote_head_points_at) {
708                                 const char *head = remote_head_points_at->name;
709                                 if (!skip_prefix(head, "refs/heads/", &head))
710                                         die("BUG: remote HEAD points at non-head?");
711
712                                 strbuf_addf(&value, "+%s:%s%s", remote_head_points_at->name,
713                                                 branch_top->buf, head);
714                         }
715                         /*
716                          * otherwise, the next "git fetch" will
717                          * simply fetch from HEAD without updating
718                          * any remote-tracking branch, which is what
719                          * we want.
720                          */
721                 } else {
722                         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top->buf);
723                 }
724                 /* Configure the remote */
725                 if (value.len) {
726                         strbuf_addf(&key, "remote.%s.fetch", option_origin);
727                         git_config_set_multivar(key.buf, value.buf, "^$", 0);
728                         strbuf_reset(&key);
729
730                         if (option_mirror) {
731                                 strbuf_addf(&key, "remote.%s.mirror", option_origin);
732                                 git_config_set(key.buf, "true");
733                                 strbuf_reset(&key);
734                         }
735                 }
736         }
737
738         strbuf_release(&key);
739         strbuf_release(&value);
740 }
741
742 static void dissociate_from_references(void)
743 {
744         static const char* argv[] = { "repack", "-a", "-d", NULL };
745
746         if (run_command_v_opt(argv, RUN_GIT_CMD|RUN_COMMAND_NO_STDIN))
747                 die(_("cannot repack to clean up"));
748         if (unlink(git_path("objects/info/alternates")) && errno != ENOENT)
749                 die_errno(_("cannot unlink temporary alternates file"));
750 }
751
752 int cmd_clone(int argc, const char **argv, const char *prefix)
753 {
754         int is_bundle = 0, is_local;
755         struct stat buf;
756         const char *repo_name, *repo, *work_tree, *git_dir;
757         char *path, *dir;
758         int dest_exists;
759         const struct ref *refs, *remote_head;
760         const struct ref *remote_head_points_at;
761         const struct ref *our_head_points_at;
762         struct ref *mapped_refs;
763         const struct ref *ref;
764         struct strbuf key = STRBUF_INIT, value = STRBUF_INIT;
765         struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
766         struct transport *transport = NULL;
767         const char *src_ref_prefix = "refs/heads/";
768         struct remote *remote;
769         int err = 0, complete_refs_before_fetch = 1;
770
771         struct refspec *refspec;
772         const char *fetch_pattern;
773
774         packet_trace_identity("clone");
775         argc = parse_options(argc, argv, prefix, builtin_clone_options,
776                              builtin_clone_usage, 0);
777
778         if (argc > 2)
779                 usage_msg_opt(_("Too many arguments."),
780                         builtin_clone_usage, builtin_clone_options);
781
782         if (argc == 0)
783                 usage_msg_opt(_("You must specify a repository to clone."),
784                         builtin_clone_usage, builtin_clone_options);
785
786         if (option_single_branch == -1)
787                 option_single_branch = option_depth ? 1 : 0;
788
789         if (option_mirror)
790                 option_bare = 1;
791
792         if (option_bare) {
793                 if (option_origin)
794                         die(_("--bare and --origin %s options are incompatible."),
795                             option_origin);
796                 if (real_git_dir)
797                         die(_("--bare and --separate-git-dir are incompatible."));
798                 option_no_checkout = 1;
799         }
800
801         if (!option_origin)
802                 option_origin = "origin";
803
804         repo_name = argv[0];
805
806         path = get_repo_path(repo_name, &is_bundle);
807         if (path)
808                 repo = xstrdup(absolute_path(repo_name));
809         else if (!strchr(repo_name, ':'))
810                 die(_("repository '%s' does not exist"), repo_name);
811         else
812                 repo = repo_name;
813
814         /* no need to be strict, transport_set_option() will validate it again */
815         if (option_depth && atoi(option_depth) < 1)
816                 die(_("depth %s is not a positive number"), option_depth);
817
818         if (argc == 2)
819                 dir = xstrdup(argv[1]);
820         else
821                 dir = guess_dir_name(repo_name, is_bundle, option_bare);
822         strip_trailing_slashes(dir);
823
824         dest_exists = !stat(dir, &buf);
825         if (dest_exists && !is_empty_dir(dir))
826                 die(_("destination path '%s' already exists and is not "
827                         "an empty directory."), dir);
828
829         strbuf_addf(&reflog_msg, "clone: from %s", repo);
830
831         if (option_bare)
832                 work_tree = NULL;
833         else {
834                 work_tree = getenv("GIT_WORK_TREE");
835                 if (work_tree && !stat(work_tree, &buf))
836                         die(_("working tree '%s' already exists."), work_tree);
837         }
838
839         if (option_bare || work_tree)
840                 git_dir = xstrdup(dir);
841         else {
842                 work_tree = dir;
843                 git_dir = mkpathdup("%s/.git", dir);
844         }
845
846         atexit(remove_junk);
847         sigchain_push_common(remove_junk_on_signal);
848
849         if (!option_bare) {
850                 if (safe_create_leading_directories_const(work_tree) < 0)
851                         die_errno(_("could not create leading directories of '%s'"),
852                                   work_tree);
853                 if (!dest_exists && mkdir(work_tree, 0777))
854                         die_errno(_("could not create work tree dir '%s'"),
855                                   work_tree);
856                 junk_work_tree = work_tree;
857                 set_git_work_tree(work_tree);
858         }
859
860         junk_git_dir = git_dir;
861         if (safe_create_leading_directories_const(git_dir) < 0)
862                 die(_("could not create leading directories of '%s'"), git_dir);
863
864         set_git_dir_init(git_dir, real_git_dir, 0);
865         if (real_git_dir) {
866                 git_dir = real_git_dir;
867                 junk_git_dir = real_git_dir;
868         }
869
870         if (0 <= option_verbosity) {
871                 if (option_bare)
872                         fprintf(stderr, _("Cloning into bare repository '%s'...\n"), dir);
873                 else
874                         fprintf(stderr, _("Cloning into '%s'...\n"), dir);
875         }
876         init_db(option_template, INIT_DB_QUIET);
877         write_config(&option_config);
878
879         git_config(git_default_config, NULL);
880
881         if (option_bare) {
882                 if (option_mirror)
883                         src_ref_prefix = "refs/";
884                 strbuf_addstr(&branch_top, src_ref_prefix);
885
886                 git_config_set("core.bare", "true");
887         } else {
888                 strbuf_addf(&branch_top, "refs/remotes/%s/", option_origin);
889         }
890
891         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top.buf);
892         strbuf_addf(&key, "remote.%s.url", option_origin);
893         git_config_set(key.buf, repo);
894         strbuf_reset(&key);
895
896         if (option_reference.nr)
897                 setup_reference();
898         else if (option_dissociate) {
899                 warning(_("--dissociate given, but there is no --reference"));
900                 option_dissociate = 0;
901         }
902
903         fetch_pattern = value.buf;
904         refspec = parse_fetch_refspec(1, &fetch_pattern);
905
906         strbuf_reset(&value);
907
908         remote = remote_get(option_origin);
909         transport = transport_get(remote, remote->url[0]);
910         path = get_repo_path(remote->url[0], &is_bundle);
911         is_local = option_local != 0 && path && !is_bundle;
912         if (is_local) {
913                 if (option_depth)
914                         warning(_("--depth is ignored in local clones; use file:// instead."));
915                 if (!access(mkpath("%s/shallow", path), F_OK)) {
916                         if (option_local > 0)
917                                 warning(_("source repository is shallow, ignoring --local"));
918                         is_local = 0;
919                 }
920         }
921         if (option_local > 0 && !is_local)
922                 warning(_("--local is ignored"));
923         transport->cloning = 1;
924
925         if (!transport->get_refs_list || (!is_local && !transport->fetch))
926                 die(_("Don't know how to clone %s"), transport->url);
927
928         transport_set_option(transport, TRANS_OPT_KEEP, "yes");
929
930         if (option_depth)
931                 transport_set_option(transport, TRANS_OPT_DEPTH,
932                                      option_depth);
933         if (option_single_branch)
934                 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
935
936         transport_set_verbosity(transport, option_verbosity, option_progress);
937
938         if (option_upload_pack)
939                 transport_set_option(transport, TRANS_OPT_UPLOADPACK,
940                                      option_upload_pack);
941
942         if (transport->smart_options && !option_depth)
943                 transport->smart_options->check_self_contained_and_connected = 1;
944
945         refs = transport_get_remote_refs(transport);
946
947         if (refs) {
948                 mapped_refs = wanted_peer_refs(refs, refspec);
949                 /*
950                  * transport_get_remote_refs() may return refs with null sha-1
951                  * in mapped_refs (see struct transport->get_refs_list
952                  * comment). In that case we need fetch it early because
953                  * remote_head code below relies on it.
954                  *
955                  * for normal clones, transport_get_remote_refs() should
956                  * return reliable ref set, we can delay cloning until after
957                  * remote HEAD check.
958                  */
959                 for (ref = refs; ref; ref = ref->next)
960                         if (is_null_sha1(ref->old_sha1)) {
961                                 complete_refs_before_fetch = 0;
962                                 break;
963                         }
964
965                 if (!is_local && !complete_refs_before_fetch)
966                         transport_fetch_refs(transport, mapped_refs);
967
968                 remote_head = find_ref_by_name(refs, "HEAD");
969                 remote_head_points_at =
970                         guess_remote_head(remote_head, mapped_refs, 0);
971
972                 if (option_branch) {
973                         our_head_points_at =
974                                 find_remote_branch(mapped_refs, option_branch);
975
976                         if (!our_head_points_at)
977                                 die(_("Remote branch %s not found in upstream %s"),
978                                     option_branch, option_origin);
979                 }
980                 else
981                         our_head_points_at = remote_head_points_at;
982         }
983         else {
984                 if (option_branch)
985                         die(_("Remote branch %s not found in upstream %s"),
986                                         option_branch, option_origin);
987
988                 warning(_("You appear to have cloned an empty repository."));
989                 mapped_refs = NULL;
990                 our_head_points_at = NULL;
991                 remote_head_points_at = NULL;
992                 remote_head = NULL;
993                 option_no_checkout = 1;
994                 if (!option_bare)
995                         install_branch_config(0, "master", option_origin,
996                                               "refs/heads/master");
997         }
998
999         write_refspec_config(src_ref_prefix, our_head_points_at,
1000                         remote_head_points_at, &branch_top);
1001
1002         if (is_local)
1003                 clone_local(path, git_dir);
1004         else if (refs && complete_refs_before_fetch)
1005                 transport_fetch_refs(transport, mapped_refs);
1006
1007         update_remote_refs(refs, mapped_refs, remote_head_points_at,
1008                            branch_top.buf, reflog_msg.buf, transport, !is_local);
1009
1010         update_head(our_head_points_at, remote_head, reflog_msg.buf);
1011
1012         transport_unlock_pack(transport);
1013         transport_disconnect(transport);
1014
1015         if (option_dissociate)
1016                 dissociate_from_references();
1017
1018         junk_mode = JUNK_LEAVE_REPO;
1019         err = checkout();
1020
1021         strbuf_release(&reflog_msg);
1022         strbuf_release(&branch_top);
1023         strbuf_release(&key);
1024         strbuf_release(&value);
1025         junk_mode = JUNK_LEAVE_ALL;
1026
1027         free(refspec);
1028         return err;
1029 }