Merge branch 'nd/dwim-wildcards-as-pathspecs'
[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 struct option builtin_clone_options[] = {
55         OPT__VERBOSITY(&option_verbosity),
56         OPT_BOOL(0, "progress", &option_progress,
57                  N_("force progress reporting")),
58         OPT_BOOL('n', "no-checkout", &option_no_checkout,
59                  N_("don't create a checkout")),
60         OPT_BOOL(0, "bare", &option_bare, N_("create a bare repository")),
61         OPT_HIDDEN_BOOL(0, "naked", &option_bare,
62                         N_("create a bare repository")),
63         OPT_BOOL(0, "mirror", &option_mirror,
64                  N_("create a mirror repository (implies bare)")),
65         OPT_BOOL('l', "local", &option_local,
66                 N_("to clone from a local repository")),
67         OPT_BOOL(0, "no-hardlinks", &option_no_hardlinks,
68                     N_("don't use local hardlinks, always copy")),
69         OPT_BOOL('s', "shared", &option_shared,
70                     N_("setup as shared repository")),
71         OPT_BOOL(0, "recursive", &option_recursive,
72                     N_("initialize submodules in the clone")),
73         OPT_BOOL(0, "recurse-submodules", &option_recursive,
74                     N_("initialize submodules in the clone")),
75         OPT_STRING(0, "template", &option_template, N_("template-directory"),
76                    N_("directory from which templates will be used")),
77         OPT_STRING_LIST(0, "reference", &option_reference, N_("repo"),
78                         N_("reference repository")),
79         OPT_BOOL(0, "dissociate", &option_dissociate,
80                  N_("use --reference only while cloning")),
81         OPT_STRING('o', "origin", &option_origin, N_("name"),
82                    N_("use <name> instead of 'origin' to track upstream")),
83         OPT_STRING('b', "branch", &option_branch, N_("branch"),
84                    N_("checkout <branch> instead of the remote's HEAD")),
85         OPT_STRING('u', "upload-pack", &option_upload_pack, N_("path"),
86                    N_("path to git-upload-pack on the remote")),
87         OPT_STRING(0, "depth", &option_depth, N_("depth"),
88                     N_("create a shallow clone of that depth")),
89         OPT_BOOL(0, "single-branch", &option_single_branch,
90                     N_("clone only one branch, HEAD or --branch")),
91         OPT_STRING(0, "separate-git-dir", &real_git_dir, N_("gitdir"),
92                    N_("separate git dir from working tree")),
93         OPT_STRING_LIST('c', "config", &option_config, N_("key=value"),
94                         N_("set config inside the new repository")),
95         OPT_END()
96 };
97
98 static const char *argv_submodule[] = {
99         "submodule", "update", "--init", "--recursive", NULL
100 };
101
102 static const char *get_repo_path_1(struct strbuf *path, int *is_bundle)
103 {
104         static char *suffix[] = { "/.git", "", ".git/.git", ".git" };
105         static char *bundle_suffix[] = { ".bundle", "" };
106         size_t baselen = path->len;
107         struct stat st;
108         int i;
109
110         for (i = 0; i < ARRAY_SIZE(suffix); i++) {
111                 strbuf_setlen(path, baselen);
112                 strbuf_addstr(path, suffix[i]);
113                 if (stat(path->buf, &st))
114                         continue;
115                 if (S_ISDIR(st.st_mode) && is_git_directory(path->buf)) {
116                         *is_bundle = 0;
117                         return path->buf;
118                 } else if (S_ISREG(st.st_mode) && st.st_size > 8) {
119                         /* Is it a "gitfile"? */
120                         char signature[8];
121                         const char *dst;
122                         int len, fd = open(path->buf, O_RDONLY);
123                         if (fd < 0)
124                                 continue;
125                         len = read_in_full(fd, signature, 8);
126                         close(fd);
127                         if (len != 8 || strncmp(signature, "gitdir: ", 8))
128                                 continue;
129                         dst = read_gitfile(path->buf);
130                         if (dst) {
131                                 *is_bundle = 0;
132                                 return dst;
133                         }
134                 }
135         }
136
137         for (i = 0; i < ARRAY_SIZE(bundle_suffix); i++) {
138                 strbuf_setlen(path, baselen);
139                 strbuf_addstr(path, bundle_suffix[i]);
140                 if (!stat(path->buf, &st) && S_ISREG(st.st_mode)) {
141                         *is_bundle = 1;
142                         return path->buf;
143                 }
144         }
145
146         return NULL;
147 }
148
149 static char *get_repo_path(const char *repo, int *is_bundle)
150 {
151         struct strbuf path = STRBUF_INIT;
152         const char *raw;
153         char *canon;
154
155         strbuf_addstr(&path, repo);
156         raw = get_repo_path_1(&path, is_bundle);
157         canon = raw ? xstrdup(absolute_path(raw)) : NULL;
158         strbuf_release(&path);
159         return canon;
160 }
161
162 static char *guess_dir_name(const char *repo, int is_bundle, int is_bare)
163 {
164         const char *end = repo + strlen(repo), *start, *ptr;
165         size_t len;
166         char *dir;
167
168         /*
169          * Skip scheme.
170          */
171         start = strstr(repo, "://");
172         if (start == NULL)
173                 start = repo;
174         else
175                 start += 3;
176
177         /*
178          * Skip authentication data. The stripping does happen
179          * greedily, such that we strip up to the last '@' inside
180          * the host part.
181          */
182         for (ptr = start; ptr < end && !is_dir_sep(*ptr); ptr++) {
183                 if (*ptr == '@')
184                         start = ptr + 1;
185         }
186
187         /*
188          * Strip trailing spaces, slashes and /.git
189          */
190         while (start < end && (is_dir_sep(end[-1]) || isspace(end[-1])))
191                 end--;
192         if (end - start > 5 && is_dir_sep(end[-5]) &&
193             !strncmp(end - 4, ".git", 4)) {
194                 end -= 5;
195                 while (start < end && is_dir_sep(end[-1]))
196                         end--;
197         }
198
199         /*
200          * Strip trailing port number if we've got only a
201          * hostname (that is, there is no dir separator but a
202          * colon). This check is required such that we do not
203          * strip URI's like '/foo/bar:2222.git', which should
204          * result in a dir '2222' being guessed due to backwards
205          * compatibility.
206          */
207         if (memchr(start, '/', end - start) == NULL
208             && memchr(start, ':', end - start) != NULL) {
209                 ptr = end;
210                 while (start < ptr && isdigit(ptr[-1]) && ptr[-1] != ':')
211                         ptr--;
212                 if (start < ptr && ptr[-1] == ':')
213                         end = ptr - 1;
214         }
215
216         /*
217          * Find last component. To remain backwards compatible we
218          * also regard colons as path separators, such that
219          * cloning a repository 'foo:bar.git' would result in a
220          * directory 'bar' being guessed.
221          */
222         ptr = end;
223         while (start < ptr && !is_dir_sep(ptr[-1]) && ptr[-1] != ':')
224                 ptr--;
225         start = ptr;
226
227         /*
228          * Strip .{bundle,git}.
229          */
230         len = end - start;
231         strip_suffix_mem(start, &len, is_bundle ? ".bundle" : ".git");
232
233         if (!len || (len == 1 && *start == '/'))
234             die("No directory name could be guessed.\n"
235                 "Please specify a directory on the command line");
236
237         if (is_bare)
238                 dir = xstrfmt("%.*s.git", (int)len, start);
239         else
240                 dir = xstrndup(start, len);
241         /*
242          * Replace sequences of 'control' characters and whitespace
243          * with one ascii space, remove leading and trailing spaces.
244          */
245         if (*dir) {
246                 char *out = dir;
247                 int prev_space = 1 /* strip leading whitespace */;
248                 for (end = dir; *end; ++end) {
249                         char ch = *end;
250                         if ((unsigned char)ch < '\x20')
251                                 ch = '\x20';
252                         if (isspace(ch)) {
253                                 if (prev_space)
254                                         continue;
255                                 prev_space = 1;
256                         } else
257                                 prev_space = 0;
258                         *out++ = ch;
259                 }
260                 *out = '\0';
261                 if (out > dir && prev_space)
262                         out[-1] = '\0';
263         }
264         return dir;
265 }
266
267 static void strip_trailing_slashes(char *dir)
268 {
269         char *end = dir + strlen(dir);
270
271         while (dir < end - 1 && is_dir_sep(end[-1]))
272                 end--;
273         *end = '\0';
274 }
275
276 static int add_one_reference(struct string_list_item *item, void *cb_data)
277 {
278         char *ref_git;
279         const char *repo;
280         struct strbuf alternate = STRBUF_INIT;
281
282         /* Beware: read_gitfile(), real_path() and mkpath() return static buffer */
283         ref_git = xstrdup(real_path(item->string));
284
285         repo = read_gitfile(ref_git);
286         if (!repo)
287                 repo = read_gitfile(mkpath("%s/.git", ref_git));
288         if (repo) {
289                 free(ref_git);
290                 ref_git = xstrdup(repo);
291         }
292
293         if (!repo && is_directory(mkpath("%s/.git/objects", ref_git))) {
294                 char *ref_git_git = mkpathdup("%s/.git", ref_git);
295                 free(ref_git);
296                 ref_git = ref_git_git;
297         } else if (!is_directory(mkpath("%s/objects", ref_git))) {
298                 struct strbuf sb = STRBUF_INIT;
299                 if (get_common_dir(&sb, ref_git))
300                         die(_("reference repository '%s' as a linked checkout is not supported yet."),
301                             item->string);
302                 die(_("reference repository '%s' is not a local repository."),
303                     item->string);
304         }
305
306         if (!access(mkpath("%s/shallow", ref_git), F_OK))
307                 die(_("reference repository '%s' is shallow"), item->string);
308
309         if (!access(mkpath("%s/info/grafts", ref_git), F_OK))
310                 die(_("reference repository '%s' is grafted"), item->string);
311
312         strbuf_addf(&alternate, "%s/objects", ref_git);
313         add_to_alternates_file(alternate.buf);
314         strbuf_release(&alternate);
315         free(ref_git);
316         return 0;
317 }
318
319 static void setup_reference(void)
320 {
321         for_each_string_list(&option_reference, add_one_reference, NULL);
322 }
323
324 static void copy_alternates(struct strbuf *src, struct strbuf *dst,
325                             const char *src_repo)
326 {
327         /*
328          * Read from the source objects/info/alternates file
329          * and copy the entries to corresponding file in the
330          * destination repository with add_to_alternates_file().
331          * Both src and dst have "$path/objects/info/alternates".
332          *
333          * Instead of copying bit-for-bit from the original,
334          * we need to append to existing one so that the already
335          * created entry via "clone -s" is not lost, and also
336          * to turn entries with paths relative to the original
337          * absolute, so that they can be used in the new repository.
338          */
339         FILE *in = fopen(src->buf, "r");
340         struct strbuf line = STRBUF_INIT;
341
342         while (strbuf_getline(&line, in) != EOF) {
343                 char *abs_path;
344                 if (!line.len || line.buf[0] == '#')
345                         continue;
346                 if (is_absolute_path(line.buf)) {
347                         add_to_alternates_file(line.buf);
348                         continue;
349                 }
350                 abs_path = mkpathdup("%s/objects/%s", src_repo, line.buf);
351                 normalize_path_copy(abs_path, abs_path);
352                 add_to_alternates_file(abs_path);
353                 free(abs_path);
354         }
355         strbuf_release(&line);
356         fclose(in);
357 }
358
359 static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
360                                    const char *src_repo, int src_baselen)
361 {
362         struct dirent *de;
363         struct stat buf;
364         int src_len, dest_len;
365         DIR *dir;
366
367         dir = opendir(src->buf);
368         if (!dir)
369                 die_errno(_("failed to open '%s'"), src->buf);
370
371         if (mkdir(dest->buf, 0777)) {
372                 if (errno != EEXIST)
373                         die_errno(_("failed to create directory '%s'"), dest->buf);
374                 else if (stat(dest->buf, &buf))
375                         die_errno(_("failed to stat '%s'"), dest->buf);
376                 else if (!S_ISDIR(buf.st_mode))
377                         die(_("%s exists and is not a directory"), dest->buf);
378         }
379
380         strbuf_addch(src, '/');
381         src_len = src->len;
382         strbuf_addch(dest, '/');
383         dest_len = dest->len;
384
385         while ((de = readdir(dir)) != NULL) {
386                 strbuf_setlen(src, src_len);
387                 strbuf_addstr(src, de->d_name);
388                 strbuf_setlen(dest, dest_len);
389                 strbuf_addstr(dest, de->d_name);
390                 if (stat(src->buf, &buf)) {
391                         warning (_("failed to stat %s\n"), src->buf);
392                         continue;
393                 }
394                 if (S_ISDIR(buf.st_mode)) {
395                         if (de->d_name[0] != '.')
396                                 copy_or_link_directory(src, dest,
397                                                        src_repo, src_baselen);
398                         continue;
399                 }
400
401                 /* Files that cannot be copied bit-for-bit... */
402                 if (!strcmp(src->buf + src_baselen, "/info/alternates")) {
403                         copy_alternates(src, dest, src_repo);
404                         continue;
405                 }
406
407                 if (unlink(dest->buf) && errno != ENOENT)
408                         die_errno(_("failed to unlink '%s'"), dest->buf);
409                 if (!option_no_hardlinks) {
410                         if (!link(src->buf, dest->buf))
411                                 continue;
412                         if (option_local > 0)
413                                 die_errno(_("failed to create link '%s'"), dest->buf);
414                         option_no_hardlinks = 1;
415                 }
416                 if (copy_file_with_time(dest->buf, src->buf, 0666))
417                         die_errno(_("failed to copy file to '%s'"), dest->buf);
418         }
419         closedir(dir);
420 }
421
422 static void clone_local(const char *src_repo, const char *dest_repo)
423 {
424         if (option_shared) {
425                 struct strbuf alt = STRBUF_INIT;
426                 strbuf_addf(&alt, "%s/objects", src_repo);
427                 add_to_alternates_file(alt.buf);
428                 strbuf_release(&alt);
429         } else {
430                 struct strbuf src = STRBUF_INIT;
431                 struct strbuf dest = STRBUF_INIT;
432                 get_common_dir(&src, src_repo);
433                 get_common_dir(&dest, dest_repo);
434                 strbuf_addstr(&src, "/objects");
435                 strbuf_addstr(&dest, "/objects");
436                 copy_or_link_directory(&src, &dest, src_repo, src.len);
437                 strbuf_release(&src);
438                 strbuf_release(&dest);
439         }
440
441         if (0 <= option_verbosity)
442                 fprintf(stderr, _("done.\n"));
443 }
444
445 static const char *junk_work_tree;
446 static const char *junk_git_dir;
447 static enum {
448         JUNK_LEAVE_NONE,
449         JUNK_LEAVE_REPO,
450         JUNK_LEAVE_ALL
451 } junk_mode = JUNK_LEAVE_NONE;
452
453 static const char junk_leave_repo_msg[] =
454 N_("Clone succeeded, but checkout failed.\n"
455    "You can inspect what was checked out with 'git status'\n"
456    "and retry the checkout with 'git checkout -f HEAD'\n");
457
458 static void remove_junk(void)
459 {
460         struct strbuf sb = STRBUF_INIT;
461
462         switch (junk_mode) {
463         case JUNK_LEAVE_REPO:
464                 warning("%s", _(junk_leave_repo_msg));
465                 /* fall-through */
466         case JUNK_LEAVE_ALL:
467                 return;
468         default:
469                 /* proceed to removal */
470                 break;
471         }
472
473         if (junk_git_dir) {
474                 strbuf_addstr(&sb, junk_git_dir);
475                 remove_dir_recursively(&sb, 0);
476                 strbuf_reset(&sb);
477         }
478         if (junk_work_tree) {
479                 strbuf_addstr(&sb, junk_work_tree);
480                 remove_dir_recursively(&sb, 0);
481                 strbuf_reset(&sb);
482         }
483 }
484
485 static void remove_junk_on_signal(int signo)
486 {
487         remove_junk();
488         sigchain_pop(signo);
489         raise(signo);
490 }
491
492 static struct ref *find_remote_branch(const struct ref *refs, const char *branch)
493 {
494         struct ref *ref;
495         struct strbuf head = STRBUF_INIT;
496         strbuf_addstr(&head, "refs/heads/");
497         strbuf_addstr(&head, branch);
498         ref = find_ref_by_name(refs, head.buf);
499         strbuf_release(&head);
500
501         if (ref)
502                 return ref;
503
504         strbuf_addstr(&head, "refs/tags/");
505         strbuf_addstr(&head, branch);
506         ref = find_ref_by_name(refs, head.buf);
507         strbuf_release(&head);
508
509         return ref;
510 }
511
512 static struct ref *wanted_peer_refs(const struct ref *refs,
513                 struct refspec *refspec)
514 {
515         struct ref *head = copy_ref(find_ref_by_name(refs, "HEAD"));
516         struct ref *local_refs = head;
517         struct ref **tail = head ? &head->next : &local_refs;
518
519         if (option_single_branch) {
520                 struct ref *remote_head = NULL;
521
522                 if (!option_branch)
523                         remote_head = guess_remote_head(head, refs, 0);
524                 else {
525                         local_refs = NULL;
526                         tail = &local_refs;
527                         remote_head = copy_ref(find_remote_branch(refs, option_branch));
528                 }
529
530                 if (!remote_head && option_branch)
531                         warning(_("Could not find remote branch %s to clone."),
532                                 option_branch);
533                 else {
534                         get_fetch_map(remote_head, refspec, &tail, 0);
535
536                         /* if --branch=tag, pull the requested tag explicitly */
537                         get_fetch_map(remote_head, tag_refspec, &tail, 0);
538                 }
539         } else
540                 get_fetch_map(refs, refspec, &tail, 0);
541
542         if (!option_mirror && !option_single_branch)
543                 get_fetch_map(refs, tag_refspec, &tail, 0);
544
545         return local_refs;
546 }
547
548 static void write_remote_refs(const struct ref *local_refs)
549 {
550         const struct ref *r;
551
552         struct ref_transaction *t;
553         struct strbuf err = STRBUF_INIT;
554
555         t = ref_transaction_begin(&err);
556         if (!t)
557                 die("%s", err.buf);
558
559         for (r = local_refs; r; r = r->next) {
560                 if (!r->peer_ref)
561                         continue;
562                 if (ref_transaction_create(t, r->peer_ref->name, r->old_oid.hash,
563                                            0, NULL, &err))
564                         die("%s", err.buf);
565         }
566
567         if (initial_ref_transaction_commit(t, &err))
568                 die("%s", err.buf);
569
570         strbuf_release(&err);
571         ref_transaction_free(t);
572 }
573
574 static void write_followtags(const struct ref *refs, const char *msg)
575 {
576         const struct ref *ref;
577         for (ref = refs; ref; ref = ref->next) {
578                 if (!starts_with(ref->name, "refs/tags/"))
579                         continue;
580                 if (ends_with(ref->name, "^{}"))
581                         continue;
582                 if (!has_object_file(&ref->old_oid))
583                         continue;
584                 update_ref(msg, ref->name, ref->old_oid.hash,
585                            NULL, 0, UPDATE_REFS_DIE_ON_ERR);
586         }
587 }
588
589 static int iterate_ref_map(void *cb_data, unsigned char sha1[20])
590 {
591         struct ref **rm = cb_data;
592         struct ref *ref = *rm;
593
594         /*
595          * Skip anything missing a peer_ref, which we are not
596          * actually going to write a ref for.
597          */
598         while (ref && !ref->peer_ref)
599                 ref = ref->next;
600         /* Returning -1 notes "end of list" to the caller. */
601         if (!ref)
602                 return -1;
603
604         hashcpy(sha1, ref->old_oid.hash);
605         *rm = ref->next;
606         return 0;
607 }
608
609 static void update_remote_refs(const struct ref *refs,
610                                const struct ref *mapped_refs,
611                                const struct ref *remote_head_points_at,
612                                const char *branch_top,
613                                const char *msg,
614                                struct transport *transport,
615                                int check_connectivity)
616 {
617         const struct ref *rm = mapped_refs;
618
619         if (check_connectivity) {
620                 if (transport->progress)
621                         fprintf(stderr, _("Checking connectivity... "));
622                 if (check_everything_connected_with_transport(iterate_ref_map,
623                                                               0, &rm, transport))
624                         die(_("remote did not send all necessary objects"));
625                 if (transport->progress)
626                         fprintf(stderr, _("done.\n"));
627         }
628
629         if (refs) {
630                 write_remote_refs(mapped_refs);
631                 if (option_single_branch)
632                         write_followtags(refs, msg);
633         }
634
635         if (remote_head_points_at && !option_bare) {
636                 struct strbuf head_ref = STRBUF_INIT;
637                 strbuf_addstr(&head_ref, branch_top);
638                 strbuf_addstr(&head_ref, "HEAD");
639                 if (create_symref(head_ref.buf,
640                                   remote_head_points_at->peer_ref->name,
641                                   msg) < 0)
642                         die("unable to update %s", head_ref.buf);
643                 strbuf_release(&head_ref);
644         }
645 }
646
647 static void update_head(const struct ref *our, const struct ref *remote,
648                         const char *msg)
649 {
650         const char *head;
651         if (our && skip_prefix(our->name, "refs/heads/", &head)) {
652                 /* Local default branch link */
653                 if (create_symref("HEAD", our->name, NULL) < 0)
654                         die("unable to update HEAD");
655                 if (!option_bare) {
656                         update_ref(msg, "HEAD", our->old_oid.hash, NULL, 0,
657                                    UPDATE_REFS_DIE_ON_ERR);
658                         install_branch_config(0, head, option_origin, our->name);
659                 }
660         } else if (our) {
661                 struct commit *c = lookup_commit_reference(our->old_oid.hash);
662                 /* --branch specifies a non-branch (i.e. tags), detach HEAD */
663                 update_ref(msg, "HEAD", c->object.oid.hash,
664                            NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
665         } else if (remote) {
666                 /*
667                  * We know remote HEAD points to a non-branch, or
668                  * HEAD points to a branch but we don't know which one.
669                  * Detach HEAD in all these cases.
670                  */
671                 update_ref(msg, "HEAD", remote->old_oid.hash,
672                            NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
673         }
674 }
675
676 static int checkout(void)
677 {
678         unsigned char sha1[20];
679         char *head;
680         struct lock_file *lock_file;
681         struct unpack_trees_options opts;
682         struct tree *tree;
683         struct tree_desc t;
684         int err = 0;
685
686         if (option_no_checkout)
687                 return 0;
688
689         head = resolve_refdup("HEAD", RESOLVE_REF_READING, sha1, NULL);
690         if (!head) {
691                 warning(_("remote HEAD refers to nonexistent ref, "
692                           "unable to checkout.\n"));
693                 return 0;
694         }
695         if (!strcmp(head, "HEAD")) {
696                 if (advice_detached_head)
697                         detach_advice(sha1_to_hex(sha1));
698         } else {
699                 if (!starts_with(head, "refs/heads/"))
700                         die(_("HEAD not found below refs/heads!"));
701         }
702         free(head);
703
704         /* We need to be in the new work tree for the checkout */
705         setup_work_tree();
706
707         lock_file = xcalloc(1, sizeof(struct lock_file));
708         hold_locked_index(lock_file, 1);
709
710         memset(&opts, 0, sizeof opts);
711         opts.update = 1;
712         opts.merge = 1;
713         opts.fn = oneway_merge;
714         opts.verbose_update = (option_verbosity >= 0);
715         opts.src_index = &the_index;
716         opts.dst_index = &the_index;
717
718         tree = parse_tree_indirect(sha1);
719         parse_tree(tree);
720         init_tree_desc(&t, tree->buffer, tree->size);
721         if (unpack_trees(1, &t, &opts) < 0)
722                 die(_("unable to checkout working tree"));
723
724         if (write_locked_index(&the_index, lock_file, COMMIT_LOCK))
725                 die(_("unable to write new index file"));
726
727         err |= run_hook_le(NULL, "post-checkout", sha1_to_hex(null_sha1),
728                            sha1_to_hex(sha1), "1", NULL);
729
730         if (!err && option_recursive)
731                 err = run_command_v_opt(argv_submodule, RUN_GIT_CMD);
732
733         return err;
734 }
735
736 static int write_one_config(const char *key, const char *value, void *data)
737 {
738         return git_config_set_multivar(key, value ? value : "true", "^$", 0);
739 }
740
741 static void write_config(struct string_list *config)
742 {
743         int i;
744
745         for (i = 0; i < config->nr; i++) {
746                 if (git_config_parse_parameter(config->items[i].string,
747                                                write_one_config, NULL) < 0)
748                         die("unable to write parameters to config file");
749         }
750 }
751
752 static void write_refspec_config(const char *src_ref_prefix,
753                 const struct ref *our_head_points_at,
754                 const struct ref *remote_head_points_at,
755                 struct strbuf *branch_top)
756 {
757         struct strbuf key = STRBUF_INIT;
758         struct strbuf value = STRBUF_INIT;
759
760         if (option_mirror || !option_bare) {
761                 if (option_single_branch && !option_mirror) {
762                         if (option_branch) {
763                                 if (starts_with(our_head_points_at->name, "refs/tags/"))
764                                         strbuf_addf(&value, "+%s:%s", our_head_points_at->name,
765                                                 our_head_points_at->name);
766                                 else
767                                         strbuf_addf(&value, "+%s:%s%s", our_head_points_at->name,
768                                                 branch_top->buf, option_branch);
769                         } else if (remote_head_points_at) {
770                                 const char *head = remote_head_points_at->name;
771                                 if (!skip_prefix(head, "refs/heads/", &head))
772                                         die("BUG: remote HEAD points at non-head?");
773
774                                 strbuf_addf(&value, "+%s:%s%s", remote_head_points_at->name,
775                                                 branch_top->buf, head);
776                         }
777                         /*
778                          * otherwise, the next "git fetch" will
779                          * simply fetch from HEAD without updating
780                          * any remote-tracking branch, which is what
781                          * we want.
782                          */
783                 } else {
784                         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top->buf);
785                 }
786                 /* Configure the remote */
787                 if (value.len) {
788                         strbuf_addf(&key, "remote.%s.fetch", option_origin);
789                         git_config_set_multivar(key.buf, value.buf, "^$", 0);
790                         strbuf_reset(&key);
791
792                         if (option_mirror) {
793                                 strbuf_addf(&key, "remote.%s.mirror", option_origin);
794                                 git_config_set(key.buf, "true");
795                                 strbuf_reset(&key);
796                         }
797                 }
798         }
799
800         strbuf_release(&key);
801         strbuf_release(&value);
802 }
803
804 static void dissociate_from_references(void)
805 {
806         static const char* argv[] = { "repack", "-a", "-d", NULL };
807         char *alternates = git_pathdup("objects/info/alternates");
808
809         if (!access(alternates, F_OK)) {
810                 if (run_command_v_opt(argv, RUN_GIT_CMD|RUN_COMMAND_NO_STDIN))
811                         die(_("cannot repack to clean up"));
812                 if (unlink(alternates) && errno != ENOENT)
813                         die_errno(_("cannot unlink temporary alternates file"));
814         }
815         free(alternates);
816 }
817
818 int cmd_clone(int argc, const char **argv, const char *prefix)
819 {
820         int is_bundle = 0, is_local;
821         struct stat buf;
822         const char *repo_name, *repo, *work_tree, *git_dir;
823         char *path, *dir;
824         int dest_exists;
825         const struct ref *refs, *remote_head;
826         const struct ref *remote_head_points_at;
827         const struct ref *our_head_points_at;
828         struct ref *mapped_refs;
829         const struct ref *ref;
830         struct strbuf key = STRBUF_INIT, value = STRBUF_INIT;
831         struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
832         struct transport *transport = NULL;
833         const char *src_ref_prefix = "refs/heads/";
834         struct remote *remote;
835         int err = 0, complete_refs_before_fetch = 1;
836
837         struct refspec *refspec;
838         const char *fetch_pattern;
839
840         packet_trace_identity("clone");
841         argc = parse_options(argc, argv, prefix, builtin_clone_options,
842                              builtin_clone_usage, 0);
843
844         if (argc > 2)
845                 usage_msg_opt(_("Too many arguments."),
846                         builtin_clone_usage, builtin_clone_options);
847
848         if (argc == 0)
849                 usage_msg_opt(_("You must specify a repository to clone."),
850                         builtin_clone_usage, builtin_clone_options);
851
852         if (option_single_branch == -1)
853                 option_single_branch = option_depth ? 1 : 0;
854
855         if (option_mirror)
856                 option_bare = 1;
857
858         if (option_bare) {
859                 if (option_origin)
860                         die(_("--bare and --origin %s options are incompatible."),
861                             option_origin);
862                 if (real_git_dir)
863                         die(_("--bare and --separate-git-dir are incompatible."));
864                 option_no_checkout = 1;
865         }
866
867         if (!option_origin)
868                 option_origin = "origin";
869
870         repo_name = argv[0];
871
872         path = get_repo_path(repo_name, &is_bundle);
873         if (path)
874                 repo = xstrdup(absolute_path(repo_name));
875         else if (!strchr(repo_name, ':'))
876                 die(_("repository '%s' does not exist"), repo_name);
877         else
878                 repo = repo_name;
879
880         /* no need to be strict, transport_set_option() will validate it again */
881         if (option_depth && atoi(option_depth) < 1)
882                 die(_("depth %s is not a positive number"), option_depth);
883
884         if (argc == 2)
885                 dir = xstrdup(argv[1]);
886         else
887                 dir = guess_dir_name(repo_name, is_bundle, option_bare);
888         strip_trailing_slashes(dir);
889
890         dest_exists = !stat(dir, &buf);
891         if (dest_exists && !is_empty_dir(dir))
892                 die(_("destination path '%s' already exists and is not "
893                         "an empty directory."), dir);
894
895         strbuf_addf(&reflog_msg, "clone: from %s", repo);
896
897         if (option_bare)
898                 work_tree = NULL;
899         else {
900                 work_tree = getenv("GIT_WORK_TREE");
901                 if (work_tree && !stat(work_tree, &buf))
902                         die(_("working tree '%s' already exists."), work_tree);
903         }
904
905         if (option_bare || work_tree)
906                 git_dir = xstrdup(dir);
907         else {
908                 work_tree = dir;
909                 git_dir = mkpathdup("%s/.git", dir);
910         }
911
912         atexit(remove_junk);
913         sigchain_push_common(remove_junk_on_signal);
914
915         if (!option_bare) {
916                 if (safe_create_leading_directories_const(work_tree) < 0)
917                         die_errno(_("could not create leading directories of '%s'"),
918                                   work_tree);
919                 if (!dest_exists && mkdir(work_tree, 0777))
920                         die_errno(_("could not create work tree dir '%s'"),
921                                   work_tree);
922                 junk_work_tree = work_tree;
923                 set_git_work_tree(work_tree);
924         }
925
926         junk_git_dir = git_dir;
927         if (safe_create_leading_directories_const(git_dir) < 0)
928                 die(_("could not create leading directories of '%s'"), git_dir);
929
930         set_git_dir_init(git_dir, real_git_dir, 0);
931         if (real_git_dir) {
932                 git_dir = real_git_dir;
933                 junk_git_dir = real_git_dir;
934         }
935
936         if (0 <= option_verbosity) {
937                 if (option_bare)
938                         fprintf(stderr, _("Cloning into bare repository '%s'...\n"), dir);
939                 else
940                         fprintf(stderr, _("Cloning into '%s'...\n"), dir);
941         }
942         init_db(option_template, INIT_DB_QUIET);
943         write_config(&option_config);
944
945         git_config(git_default_config, NULL);
946
947         if (option_bare) {
948                 if (option_mirror)
949                         src_ref_prefix = "refs/";
950                 strbuf_addstr(&branch_top, src_ref_prefix);
951
952                 git_config_set("core.bare", "true");
953         } else {
954                 strbuf_addf(&branch_top, "refs/remotes/%s/", option_origin);
955         }
956
957         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top.buf);
958         strbuf_addf(&key, "remote.%s.url", option_origin);
959         git_config_set(key.buf, repo);
960         strbuf_reset(&key);
961
962         if (option_reference.nr)
963                 setup_reference();
964
965         fetch_pattern = value.buf;
966         refspec = parse_fetch_refspec(1, &fetch_pattern);
967
968         strbuf_reset(&value);
969
970         remote = remote_get(option_origin);
971         transport = transport_get(remote, remote->url[0]);
972         transport_set_verbosity(transport, option_verbosity, option_progress);
973
974         path = get_repo_path(remote->url[0], &is_bundle);
975         is_local = option_local != 0 && path && !is_bundle;
976         if (is_local) {
977                 if (option_depth)
978                         warning(_("--depth is ignored in local clones; use file:// instead."));
979                 if (!access(mkpath("%s/shallow", path), F_OK)) {
980                         if (option_local > 0)
981                                 warning(_("source repository is shallow, ignoring --local"));
982                         is_local = 0;
983                 }
984         }
985         if (option_local > 0 && !is_local)
986                 warning(_("--local is ignored"));
987         transport->cloning = 1;
988
989         if (!transport->get_refs_list || (!is_local && !transport->fetch))
990                 die(_("Don't know how to clone %s"), transport->url);
991
992         transport_set_option(transport, TRANS_OPT_KEEP, "yes");
993
994         if (option_depth)
995                 transport_set_option(transport, TRANS_OPT_DEPTH,
996                                      option_depth);
997         if (option_single_branch)
998                 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
999
1000         if (option_upload_pack)
1001                 transport_set_option(transport, TRANS_OPT_UPLOADPACK,
1002                                      option_upload_pack);
1003
1004         if (transport->smart_options && !option_depth)
1005                 transport->smart_options->check_self_contained_and_connected = 1;
1006
1007         refs = transport_get_remote_refs(transport);
1008
1009         if (refs) {
1010                 mapped_refs = wanted_peer_refs(refs, refspec);
1011                 /*
1012                  * transport_get_remote_refs() may return refs with null sha-1
1013                  * in mapped_refs (see struct transport->get_refs_list
1014                  * comment). In that case we need fetch it early because
1015                  * remote_head code below relies on it.
1016                  *
1017                  * for normal clones, transport_get_remote_refs() should
1018                  * return reliable ref set, we can delay cloning until after
1019                  * remote HEAD check.
1020                  */
1021                 for (ref = refs; ref; ref = ref->next)
1022                         if (is_null_oid(&ref->old_oid)) {
1023                                 complete_refs_before_fetch = 0;
1024                                 break;
1025                         }
1026
1027                 if (!is_local && !complete_refs_before_fetch)
1028                         transport_fetch_refs(transport, mapped_refs);
1029
1030                 remote_head = find_ref_by_name(refs, "HEAD");
1031                 remote_head_points_at =
1032                         guess_remote_head(remote_head, mapped_refs, 0);
1033
1034                 if (option_branch) {
1035                         our_head_points_at =
1036                                 find_remote_branch(mapped_refs, option_branch);
1037
1038                         if (!our_head_points_at)
1039                                 die(_("Remote branch %s not found in upstream %s"),
1040                                     option_branch, option_origin);
1041                 }
1042                 else
1043                         our_head_points_at = remote_head_points_at;
1044         }
1045         else {
1046                 if (option_branch)
1047                         die(_("Remote branch %s not found in upstream %s"),
1048                                         option_branch, option_origin);
1049
1050                 warning(_("You appear to have cloned an empty repository."));
1051                 mapped_refs = NULL;
1052                 our_head_points_at = NULL;
1053                 remote_head_points_at = NULL;
1054                 remote_head = NULL;
1055                 option_no_checkout = 1;
1056                 if (!option_bare)
1057                         install_branch_config(0, "master", option_origin,
1058                                               "refs/heads/master");
1059         }
1060
1061         write_refspec_config(src_ref_prefix, our_head_points_at,
1062                         remote_head_points_at, &branch_top);
1063
1064         if (is_local)
1065                 clone_local(path, git_dir);
1066         else if (refs && complete_refs_before_fetch)
1067                 transport_fetch_refs(transport, mapped_refs);
1068
1069         update_remote_refs(refs, mapped_refs, remote_head_points_at,
1070                            branch_top.buf, reflog_msg.buf, transport, !is_local);
1071
1072         update_head(our_head_points_at, remote_head, reflog_msg.buf);
1073
1074         transport_unlock_pack(transport);
1075         transport_disconnect(transport);
1076
1077         if (option_dissociate) {
1078                 close_all_packs();
1079                 dissociate_from_references();
1080         }
1081
1082         junk_mode = JUNK_LEAVE_REPO;
1083         err = checkout();
1084
1085         strbuf_release(&reflog_msg);
1086         strbuf_release(&branch_top);
1087         strbuf_release(&key);
1088         strbuf_release(&value);
1089         junk_mode = JUNK_LEAVE_ALL;
1090
1091         free(refspec);
1092         return err;
1093 }