Merge branch 'rr/push-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 "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_BOOLEAN('n', "no-checkout", &option_no_checkout,
66                     N_("don't create a checkout")),
67         OPT_BOOLEAN(0, "bare", &option_bare, N_("create a bare repository")),
68         { OPTION_BOOLEAN, 0, "naked", &option_bare, NULL,
69                 N_("create a bare repository"),
70                 PARSE_OPT_NOARG | PARSE_OPT_HIDDEN },
71         OPT_BOOLEAN(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_BOOLEAN(0, "no-hardlinks", &option_no_hardlinks,
76                     N_("don't use local hardlinks, always copy")),
77         OPT_BOOLEAN('s', "shared", &option_shared,
78                     N_("setup as shared repository")),
79         OPT_BOOLEAN(0, "recursive", &option_recursive,
80                     N_("initialize submodules in the clone")),
81         OPT_BOOLEAN(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         strbuf_addf(&alternate, "%s/objects", ref_git);
257         add_to_alternates_file(alternate.buf);
258         strbuf_release(&alternate);
259         free(ref_git);
260         return 0;
261 }
262
263 static void setup_reference(void)
264 {
265         for_each_string_list(&option_reference, add_one_reference, NULL);
266 }
267
268 static void copy_alternates(struct strbuf *src, struct strbuf *dst,
269                             const char *src_repo)
270 {
271         /*
272          * Read from the source objects/info/alternates file
273          * and copy the entries to corresponding file in the
274          * destination repository with add_to_alternates_file().
275          * Both src and dst have "$path/objects/info/alternates".
276          *
277          * Instead of copying bit-for-bit from the original,
278          * we need to append to existing one so that the already
279          * created entry via "clone -s" is not lost, and also
280          * to turn entries with paths relative to the original
281          * absolute, so that they can be used in the new repository.
282          */
283         FILE *in = fopen(src->buf, "r");
284         struct strbuf line = STRBUF_INIT;
285
286         while (strbuf_getline(&line, in, '\n') != EOF) {
287                 char *abs_path, abs_buf[PATH_MAX];
288                 if (!line.len || line.buf[0] == '#')
289                         continue;
290                 if (is_absolute_path(line.buf)) {
291                         add_to_alternates_file(line.buf);
292                         continue;
293                 }
294                 abs_path = mkpath("%s/objects/%s", src_repo, line.buf);
295                 normalize_path_copy(abs_buf, abs_path);
296                 add_to_alternates_file(abs_buf);
297         }
298         strbuf_release(&line);
299         fclose(in);
300 }
301
302 static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
303                                    const char *src_repo, int src_baselen)
304 {
305         struct dirent *de;
306         struct stat buf;
307         int src_len, dest_len;
308         DIR *dir;
309
310         dir = opendir(src->buf);
311         if (!dir)
312                 die_errno(_("failed to open '%s'"), src->buf);
313
314         if (mkdir(dest->buf, 0777)) {
315                 if (errno != EEXIST)
316                         die_errno(_("failed to create directory '%s'"), dest->buf);
317                 else if (stat(dest->buf, &buf))
318                         die_errno(_("failed to stat '%s'"), dest->buf);
319                 else if (!S_ISDIR(buf.st_mode))
320                         die(_("%s exists and is not a directory"), dest->buf);
321         }
322
323         strbuf_addch(src, '/');
324         src_len = src->len;
325         strbuf_addch(dest, '/');
326         dest_len = dest->len;
327
328         while ((de = readdir(dir)) != NULL) {
329                 strbuf_setlen(src, src_len);
330                 strbuf_addstr(src, de->d_name);
331                 strbuf_setlen(dest, dest_len);
332                 strbuf_addstr(dest, de->d_name);
333                 if (stat(src->buf, &buf)) {
334                         warning (_("failed to stat %s\n"), src->buf);
335                         continue;
336                 }
337                 if (S_ISDIR(buf.st_mode)) {
338                         if (de->d_name[0] != '.')
339                                 copy_or_link_directory(src, dest,
340                                                        src_repo, src_baselen);
341                         continue;
342                 }
343
344                 /* Files that cannot be copied bit-for-bit... */
345                 if (!strcmp(src->buf + src_baselen, "/info/alternates")) {
346                         copy_alternates(src, dest, src_repo);
347                         continue;
348                 }
349
350                 if (unlink(dest->buf) && errno != ENOENT)
351                         die_errno(_("failed to unlink '%s'"), dest->buf);
352                 if (!option_no_hardlinks) {
353                         if (!link(src->buf, dest->buf))
354                                 continue;
355                         if (option_local > 0)
356                                 die_errno(_("failed to create link '%s'"), dest->buf);
357                         option_no_hardlinks = 1;
358                 }
359                 if (copy_file_with_time(dest->buf, src->buf, 0666))
360                         die_errno(_("failed to copy file to '%s'"), dest->buf);
361         }
362         closedir(dir);
363 }
364
365 static void clone_local(const char *src_repo, const char *dest_repo)
366 {
367         if (option_shared) {
368                 struct strbuf alt = STRBUF_INIT;
369                 strbuf_addf(&alt, "%s/objects", src_repo);
370                 add_to_alternates_file(alt.buf);
371                 strbuf_release(&alt);
372         } else {
373                 struct strbuf src = STRBUF_INIT;
374                 struct strbuf dest = STRBUF_INIT;
375                 strbuf_addf(&src, "%s/objects", src_repo);
376                 strbuf_addf(&dest, "%s/objects", dest_repo);
377                 copy_or_link_directory(&src, &dest, src_repo, src.len);
378                 strbuf_release(&src);
379                 strbuf_release(&dest);
380         }
381
382         if (0 <= option_verbosity)
383                 printf(_("done.\n"));
384 }
385
386 static const char *junk_work_tree;
387 static const char *junk_git_dir;
388 static pid_t junk_pid;
389 static enum {
390         JUNK_LEAVE_NONE,
391         JUNK_LEAVE_REPO,
392         JUNK_LEAVE_ALL
393 } junk_mode = JUNK_LEAVE_NONE;
394
395 static const char junk_leave_repo_msg[] =
396 N_("Clone succeeded, but checkout failed.\n"
397    "You can inspect what was checked out with 'git status'\n"
398    "and retry the checkout with 'git checkout -f HEAD'\n");
399
400 static void remove_junk(void)
401 {
402         struct strbuf sb = STRBUF_INIT;
403
404         switch (junk_mode) {
405         case JUNK_LEAVE_REPO:
406                 warning("%s", _(junk_leave_repo_msg));
407                 /* fall-through */
408         case JUNK_LEAVE_ALL:
409                 return;
410         default:
411                 /* proceed to removal */
412                 break;
413         }
414
415         if (getpid() != junk_pid)
416                 return;
417         if (junk_git_dir) {
418                 strbuf_addstr(&sb, junk_git_dir);
419                 remove_dir_recursively(&sb, 0);
420                 strbuf_reset(&sb);
421         }
422         if (junk_work_tree) {
423                 strbuf_addstr(&sb, junk_work_tree);
424                 remove_dir_recursively(&sb, 0);
425                 strbuf_reset(&sb);
426         }
427 }
428
429 static void remove_junk_on_signal(int signo)
430 {
431         remove_junk();
432         sigchain_pop(signo);
433         raise(signo);
434 }
435
436 static struct ref *find_remote_branch(const struct ref *refs, const char *branch)
437 {
438         struct ref *ref;
439         struct strbuf head = STRBUF_INIT;
440         strbuf_addstr(&head, "refs/heads/");
441         strbuf_addstr(&head, branch);
442         ref = find_ref_by_name(refs, head.buf);
443         strbuf_release(&head);
444
445         if (ref)
446                 return ref;
447
448         strbuf_addstr(&head, "refs/tags/");
449         strbuf_addstr(&head, branch);
450         ref = find_ref_by_name(refs, head.buf);
451         strbuf_release(&head);
452
453         return ref;
454 }
455
456 static struct ref *wanted_peer_refs(const struct ref *refs,
457                 struct refspec *refspec)
458 {
459         struct ref *head = copy_ref(find_ref_by_name(refs, "HEAD"));
460         struct ref *local_refs = head;
461         struct ref **tail = head ? &head->next : &local_refs;
462
463         if (option_single_branch) {
464                 struct ref *remote_head = NULL;
465
466                 if (!option_branch)
467                         remote_head = guess_remote_head(head, refs, 0);
468                 else {
469                         local_refs = NULL;
470                         tail = &local_refs;
471                         remote_head = copy_ref(find_remote_branch(refs, option_branch));
472                 }
473
474                 if (!remote_head && option_branch)
475                         warning(_("Could not find remote branch %s to clone."),
476                                 option_branch);
477                 else {
478                         get_fetch_map(remote_head, refspec, &tail, 0);
479
480                         /* if --branch=tag, pull the requested tag explicitly */
481                         get_fetch_map(remote_head, tag_refspec, &tail, 0);
482                 }
483         } else
484                 get_fetch_map(refs, refspec, &tail, 0);
485
486         if (!option_mirror && !option_single_branch)
487                 get_fetch_map(refs, tag_refspec, &tail, 0);
488
489         return local_refs;
490 }
491
492 static void write_remote_refs(const struct ref *local_refs)
493 {
494         const struct ref *r;
495
496         for (r = local_refs; r; r = r->next) {
497                 if (!r->peer_ref)
498                         continue;
499                 add_packed_ref(r->peer_ref->name, r->old_sha1);
500         }
501
502         pack_refs(PACK_REFS_ALL);
503 }
504
505 static void write_followtags(const struct ref *refs, const char *msg)
506 {
507         const struct ref *ref;
508         for (ref = refs; ref; ref = ref->next) {
509                 if (prefixcmp(ref->name, "refs/tags/"))
510                         continue;
511                 if (!suffixcmp(ref->name, "^{}"))
512                         continue;
513                 if (!has_sha1_file(ref->old_sha1))
514                         continue;
515                 update_ref(msg, ref->name, ref->old_sha1,
516                            NULL, 0, DIE_ON_ERR);
517         }
518 }
519
520 static int iterate_ref_map(void *cb_data, unsigned char sha1[20])
521 {
522         struct ref **rm = cb_data;
523         struct ref *ref = *rm;
524
525         /*
526          * Skip anything missing a peer_ref, which we are not
527          * actually going to write a ref for.
528          */
529         while (ref && !ref->peer_ref)
530                 ref = ref->next;
531         /* Returning -1 notes "end of list" to the caller. */
532         if (!ref)
533                 return -1;
534
535         hashcpy(sha1, ref->old_sha1);
536         *rm = ref->next;
537         return 0;
538 }
539
540 static void update_remote_refs(const struct ref *refs,
541                                const struct ref *mapped_refs,
542                                const struct ref *remote_head_points_at,
543                                const char *branch_top,
544                                const char *msg,
545                                struct transport *transport)
546 {
547         const struct ref *rm = mapped_refs;
548
549         if (0 <= option_verbosity)
550                 printf(_("Checking connectivity... "));
551         if (check_everything_connected_with_transport(iterate_ref_map,
552                                                       0, &rm, transport))
553                 die(_("remote did not send all necessary objects"));
554         if (0 <= option_verbosity)
555                 printf(_("done\n"));
556
557         if (refs) {
558                 write_remote_refs(mapped_refs);
559                 if (option_single_branch)
560                         write_followtags(refs, msg);
561         }
562
563         if (remote_head_points_at && !option_bare) {
564                 struct strbuf head_ref = STRBUF_INIT;
565                 strbuf_addstr(&head_ref, branch_top);
566                 strbuf_addstr(&head_ref, "HEAD");
567                 create_symref(head_ref.buf,
568                               remote_head_points_at->peer_ref->name,
569                               msg);
570         }
571 }
572
573 static void update_head(const struct ref *our, const struct ref *remote,
574                         const char *msg)
575 {
576         if (our && !prefixcmp(our->name, "refs/heads/")) {
577                 /* Local default branch link */
578                 create_symref("HEAD", our->name, NULL);
579                 if (!option_bare) {
580                         const char *head = skip_prefix(our->name, "refs/heads/");
581                         update_ref(msg, "HEAD", our->old_sha1, NULL, 0, DIE_ON_ERR);
582                         install_branch_config(0, head, option_origin, our->name);
583                 }
584         } else if (our) {
585                 struct commit *c = lookup_commit_reference(our->old_sha1);
586                 /* --branch specifies a non-branch (i.e. tags), detach HEAD */
587                 update_ref(msg, "HEAD", c->object.sha1,
588                            NULL, REF_NODEREF, DIE_ON_ERR);
589         } else if (remote) {
590                 /*
591                  * We know remote HEAD points to a non-branch, or
592                  * HEAD points to a branch but we don't know which one.
593                  * Detach HEAD in all these cases.
594                  */
595                 update_ref(msg, "HEAD", remote->old_sha1,
596                            NULL, REF_NODEREF, DIE_ON_ERR);
597         }
598 }
599
600 static int checkout(void)
601 {
602         unsigned char sha1[20];
603         char *head;
604         struct lock_file *lock_file;
605         struct unpack_trees_options opts;
606         struct tree *tree;
607         struct tree_desc t;
608         int err = 0, fd;
609
610         if (option_no_checkout)
611                 return 0;
612
613         head = resolve_refdup("HEAD", sha1, 1, NULL);
614         if (!head) {
615                 warning(_("remote HEAD refers to nonexistent ref, "
616                           "unable to checkout.\n"));
617                 return 0;
618         }
619         if (!strcmp(head, "HEAD")) {
620                 if (advice_detached_head)
621                         detach_advice(sha1_to_hex(sha1));
622         } else {
623                 if (prefixcmp(head, "refs/heads/"))
624                         die(_("HEAD not found below refs/heads!"));
625         }
626         free(head);
627
628         /* We need to be in the new work tree for the checkout */
629         setup_work_tree();
630
631         lock_file = xcalloc(1, sizeof(struct lock_file));
632         fd = hold_locked_index(lock_file, 1);
633
634         memset(&opts, 0, sizeof opts);
635         opts.update = 1;
636         opts.merge = 1;
637         opts.fn = oneway_merge;
638         opts.verbose_update = (option_verbosity >= 0);
639         opts.src_index = &the_index;
640         opts.dst_index = &the_index;
641
642         tree = parse_tree_indirect(sha1);
643         parse_tree(tree);
644         init_tree_desc(&t, tree->buffer, tree->size);
645         if (unpack_trees(1, &t, &opts) < 0)
646                 die(_("unable to checkout working tree"));
647
648         if (write_cache(fd, active_cache, active_nr) ||
649             commit_locked_index(lock_file))
650                 die(_("unable to write new index file"));
651
652         err |= run_hook(NULL, "post-checkout", sha1_to_hex(null_sha1),
653                         sha1_to_hex(sha1), "1", NULL);
654
655         if (!err && option_recursive)
656                 err = run_command_v_opt(argv_submodule, RUN_GIT_CMD);
657
658         return err;
659 }
660
661 static int write_one_config(const char *key, const char *value, void *data)
662 {
663         return git_config_set_multivar(key, value ? value : "true", "^$", 0);
664 }
665
666 static void write_config(struct string_list *config)
667 {
668         int i;
669
670         for (i = 0; i < config->nr; i++) {
671                 if (git_config_parse_parameter(config->items[i].string,
672                                                write_one_config, NULL) < 0)
673                         die("unable to write parameters to config file");
674         }
675 }
676
677 static void write_refspec_config(const char* src_ref_prefix,
678                 const struct ref* our_head_points_at,
679                 const struct ref* remote_head_points_at, struct strbuf* branch_top)
680 {
681         struct strbuf key = STRBUF_INIT;
682         struct strbuf value = STRBUF_INIT;
683
684         if (option_mirror || !option_bare) {
685                 if (option_single_branch && !option_mirror) {
686                         if (option_branch) {
687                                 if (strstr(our_head_points_at->name, "refs/tags/"))
688                                         strbuf_addf(&value, "+%s:%s", our_head_points_at->name,
689                                                 our_head_points_at->name);
690                                 else
691                                         strbuf_addf(&value, "+%s:%s%s", our_head_points_at->name,
692                                                 branch_top->buf, option_branch);
693                         } else if (remote_head_points_at) {
694                                 strbuf_addf(&value, "+%s:%s%s", remote_head_points_at->name,
695                                                 branch_top->buf,
696                                                 skip_prefix(remote_head_points_at->name, "refs/heads/"));
697                         }
698                         /*
699                          * otherwise, the next "git fetch" will
700                          * simply fetch from HEAD without updating
701                          * any remote tracking branch, which is what
702                          * we want.
703                          */
704                 } else {
705                         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top->buf);
706                 }
707                 /* Configure the remote */
708                 if (value.len) {
709                         strbuf_addf(&key, "remote.%s.fetch", option_origin);
710                         git_config_set_multivar(key.buf, value.buf, "^$", 0);
711                         strbuf_reset(&key);
712
713                         if (option_mirror) {
714                                 strbuf_addf(&key, "remote.%s.mirror", option_origin);
715                                 git_config_set(key.buf, "true");
716                                 strbuf_reset(&key);
717                         }
718                 }
719         }
720
721         strbuf_release(&key);
722         strbuf_release(&value);
723 }
724
725 int cmd_clone(int argc, const char **argv, const char *prefix)
726 {
727         int is_bundle = 0, is_local;
728         struct stat buf;
729         const char *repo_name, *repo, *work_tree, *git_dir;
730         char *path, *dir;
731         int dest_exists;
732         const struct ref *refs, *remote_head;
733         const struct ref *remote_head_points_at;
734         const struct ref *our_head_points_at;
735         struct ref *mapped_refs;
736         const struct ref *ref;
737         struct strbuf key = STRBUF_INIT, value = STRBUF_INIT;
738         struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
739         struct transport *transport = NULL;
740         const char *src_ref_prefix = "refs/heads/";
741         struct remote *remote;
742         int err = 0, complete_refs_before_fetch = 1;
743
744         struct refspec *refspec;
745         const char *fetch_pattern;
746
747         junk_pid = getpid();
748
749         packet_trace_identity("clone");
750         argc = parse_options(argc, argv, prefix, builtin_clone_options,
751                              builtin_clone_usage, 0);
752
753         if (argc > 2)
754                 usage_msg_opt(_("Too many arguments."),
755                         builtin_clone_usage, builtin_clone_options);
756
757         if (argc == 0)
758                 usage_msg_opt(_("You must specify a repository to clone."),
759                         builtin_clone_usage, builtin_clone_options);
760
761         if (option_single_branch == -1)
762                 option_single_branch = option_depth ? 1 : 0;
763
764         if (option_mirror)
765                 option_bare = 1;
766
767         if (option_bare) {
768                 if (option_origin)
769                         die(_("--bare and --origin %s options are incompatible."),
770                             option_origin);
771                 if (real_git_dir)
772                         die(_("--bare and --separate-git-dir are incompatible."));
773                 option_no_checkout = 1;
774         }
775
776         if (!option_origin)
777                 option_origin = "origin";
778
779         repo_name = argv[0];
780
781         path = get_repo_path(repo_name, &is_bundle);
782         if (path)
783                 repo = xstrdup(absolute_path(repo_name));
784         else if (!strchr(repo_name, ':'))
785                 die(_("repository '%s' does not exist"), repo_name);
786         else
787                 repo = repo_name;
788         is_local = option_local != 0 && path && !is_bundle;
789         if (is_local && option_depth)
790                 warning(_("--depth is ignored in local clones; use file:// instead."));
791         if (option_local > 0 && !is_local)
792                 warning(_("--local is ignored"));
793
794         if (argc == 2)
795                 dir = xstrdup(argv[1]);
796         else
797                 dir = guess_dir_name(repo_name, is_bundle, option_bare);
798         strip_trailing_slashes(dir);
799
800         dest_exists = !stat(dir, &buf);
801         if (dest_exists && !is_empty_dir(dir))
802                 die(_("destination path '%s' already exists and is not "
803                         "an empty directory."), dir);
804
805         strbuf_addf(&reflog_msg, "clone: from %s", repo);
806
807         if (option_bare)
808                 work_tree = NULL;
809         else {
810                 work_tree = getenv("GIT_WORK_TREE");
811                 if (work_tree && !stat(work_tree, &buf))
812                         die(_("working tree '%s' already exists."), work_tree);
813         }
814
815         if (option_bare || work_tree)
816                 git_dir = xstrdup(dir);
817         else {
818                 work_tree = dir;
819                 git_dir = mkpathdup("%s/.git", dir);
820         }
821
822         if (!option_bare) {
823                 junk_work_tree = work_tree;
824                 if (safe_create_leading_directories_const(work_tree) < 0)
825                         die_errno(_("could not create leading directories of '%s'"),
826                                   work_tree);
827                 if (!dest_exists && mkdir(work_tree, 0777))
828                         die_errno(_("could not create work tree dir '%s'."),
829                                   work_tree);
830                 set_git_work_tree(work_tree);
831         }
832         junk_git_dir = git_dir;
833         atexit(remove_junk);
834         sigchain_push_common(remove_junk_on_signal);
835
836         if (safe_create_leading_directories_const(git_dir) < 0)
837                 die(_("could not create leading directories of '%s'"), git_dir);
838
839         set_git_dir_init(git_dir, real_git_dir, 0);
840         if (real_git_dir) {
841                 git_dir = real_git_dir;
842                 junk_git_dir = real_git_dir;
843         }
844
845         if (0 <= option_verbosity) {
846                 if (option_bare)
847                         printf(_("Cloning into bare repository '%s'...\n"), dir);
848                 else
849                         printf(_("Cloning into '%s'...\n"), dir);
850         }
851         init_db(option_template, INIT_DB_QUIET);
852         write_config(&option_config);
853
854         git_config(git_default_config, NULL);
855
856         if (option_bare) {
857                 if (option_mirror)
858                         src_ref_prefix = "refs/";
859                 strbuf_addstr(&branch_top, src_ref_prefix);
860
861                 git_config_set("core.bare", "true");
862         } else {
863                 strbuf_addf(&branch_top, "refs/remotes/%s/", option_origin);
864         }
865
866         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top.buf);
867         strbuf_addf(&key, "remote.%s.url", option_origin);
868         git_config_set(key.buf, repo);
869         strbuf_reset(&key);
870
871         if (option_reference.nr)
872                 setup_reference();
873
874         fetch_pattern = value.buf;
875         refspec = parse_fetch_refspec(1, &fetch_pattern);
876
877         strbuf_reset(&value);
878
879         remote = remote_get(option_origin);
880         transport = transport_get(remote, remote->url[0]);
881
882         if (!is_local) {
883                 if (!transport->get_refs_list || !transport->fetch)
884                         die(_("Don't know how to clone %s"), transport->url);
885
886                 transport_set_option(transport, TRANS_OPT_KEEP, "yes");
887
888                 if (option_depth)
889                         transport_set_option(transport, TRANS_OPT_DEPTH,
890                                              option_depth);
891                 if (option_single_branch)
892                         transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
893
894                 transport_set_verbosity(transport, option_verbosity, option_progress);
895
896                 if (option_upload_pack)
897                         transport_set_option(transport, TRANS_OPT_UPLOADPACK,
898                                              option_upload_pack);
899
900                 if (transport->smart_options && !option_depth)
901                         transport->smart_options->check_self_contained_and_connected = 1;
902         }
903
904         refs = transport_get_remote_refs(transport);
905
906         if (refs) {
907                 mapped_refs = wanted_peer_refs(refs, refspec);
908                 /*
909                  * transport_get_remote_refs() may return refs with null sha-1
910                  * in mapped_refs (see struct transport->get_refs_list
911                  * comment). In that case we need fetch it early because
912                  * remote_head code below relies on it.
913                  *
914                  * for normal clones, transport_get_remote_refs() should
915                  * return reliable ref set, we can delay cloning until after
916                  * remote HEAD check.
917                  */
918                 for (ref = refs; ref; ref = ref->next)
919                         if (is_null_sha1(ref->old_sha1)) {
920                                 complete_refs_before_fetch = 0;
921                                 break;
922                         }
923
924                 if (!is_local && !complete_refs_before_fetch)
925                         transport_fetch_refs(transport, mapped_refs);
926
927                 remote_head = find_ref_by_name(refs, "HEAD");
928                 remote_head_points_at =
929                         guess_remote_head(remote_head, mapped_refs, 0);
930
931                 if (option_branch) {
932                         our_head_points_at =
933                                 find_remote_branch(mapped_refs, option_branch);
934
935                         if (!our_head_points_at)
936                                 die(_("Remote branch %s not found in upstream %s"),
937                                     option_branch, option_origin);
938                 }
939                 else
940                         our_head_points_at = remote_head_points_at;
941         }
942         else {
943                 warning(_("You appear to have cloned an empty repository."));
944                 mapped_refs = NULL;
945                 our_head_points_at = NULL;
946                 remote_head_points_at = NULL;
947                 remote_head = NULL;
948                 option_no_checkout = 1;
949                 if (!option_bare)
950                         install_branch_config(0, "master", option_origin,
951                                               "refs/heads/master");
952         }
953
954         write_refspec_config(src_ref_prefix, our_head_points_at,
955                         remote_head_points_at, &branch_top);
956
957         if (is_local)
958                 clone_local(path, git_dir);
959         else if (refs && complete_refs_before_fetch)
960                 transport_fetch_refs(transport, mapped_refs);
961
962         update_remote_refs(refs, mapped_refs, remote_head_points_at,
963                            branch_top.buf, reflog_msg.buf, transport);
964
965         update_head(our_head_points_at, remote_head, reflog_msg.buf);
966
967         transport_unlock_pack(transport);
968         transport_disconnect(transport);
969
970         junk_mode = JUNK_LEAVE_REPO;
971         err = checkout();
972
973         strbuf_release(&reflog_msg);
974         strbuf_release(&branch_top);
975         strbuf_release(&key);
976         strbuf_release(&value);
977         junk_mode = JUNK_LEAVE_ALL;
978         return err;
979 }