Merge branch 'jc/makefile-redirection-stderr'
[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 enum transport_family family;
51 static struct string_list option_config;
52 static struct string_list option_reference;
53 static int option_dissociate;
54 static int max_jobs = -1;
55
56 static struct option builtin_clone_options[] = {
57         OPT__VERBOSITY(&option_verbosity),
58         OPT_BOOL(0, "progress", &option_progress,
59                  N_("force progress reporting")),
60         OPT_BOOL('n', "no-checkout", &option_no_checkout,
61                  N_("don't create a checkout")),
62         OPT_BOOL(0, "bare", &option_bare, N_("create a bare repository")),
63         OPT_HIDDEN_BOOL(0, "naked", &option_bare,
64                         N_("create a bare repository")),
65         OPT_BOOL(0, "mirror", &option_mirror,
66                  N_("create a mirror repository (implies bare)")),
67         OPT_BOOL('l', "local", &option_local,
68                 N_("to clone from a local repository")),
69         OPT_BOOL(0, "no-hardlinks", &option_no_hardlinks,
70                     N_("don't use local hardlinks, always copy")),
71         OPT_BOOL('s', "shared", &option_shared,
72                     N_("setup as shared repository")),
73         OPT_BOOL(0, "recursive", &option_recursive,
74                     N_("initialize submodules in the clone")),
75         OPT_BOOL(0, "recurse-submodules", &option_recursive,
76                     N_("initialize submodules in the clone")),
77         OPT_INTEGER('j', "jobs", &max_jobs,
78                     N_("number of submodules cloned in parallel")),
79         OPT_STRING(0, "template", &option_template, N_("template-directory"),
80                    N_("directory from which templates will be used")),
81         OPT_STRING_LIST(0, "reference", &option_reference, N_("repo"),
82                         N_("reference repository")),
83         OPT_BOOL(0, "dissociate", &option_dissociate,
84                  N_("use --reference only while cloning")),
85         OPT_STRING('o', "origin", &option_origin, N_("name"),
86                    N_("use <name> instead of 'origin' to track upstream")),
87         OPT_STRING('b', "branch", &option_branch, N_("branch"),
88                    N_("checkout <branch> instead of the remote's HEAD")),
89         OPT_STRING('u', "upload-pack", &option_upload_pack, N_("path"),
90                    N_("path to git-upload-pack on the remote")),
91         OPT_STRING(0, "depth", &option_depth, N_("depth"),
92                     N_("create a shallow clone of that depth")),
93         OPT_BOOL(0, "single-branch", &option_single_branch,
94                     N_("clone only one branch, HEAD or --branch")),
95         OPT_STRING(0, "separate-git-dir", &real_git_dir, N_("gitdir"),
96                    N_("separate git dir from working tree")),
97         OPT_STRING_LIST('c', "config", &option_config, N_("key=value"),
98                         N_("set config inside the new repository")),
99         OPT_SET_INT('4', "ipv4", &family, N_("use IPv4 addresses only"),
100                         TRANSPORT_FAMILY_IPV4),
101         OPT_SET_INT('6', "ipv6", &family, N_("use IPv6 addresses only"),
102                         TRANSPORT_FAMILY_IPV6),
103         OPT_END()
104 };
105
106 static const char *get_repo_path_1(struct strbuf *path, int *is_bundle)
107 {
108         static char *suffix[] = { "/.git", "", ".git/.git", ".git" };
109         static char *bundle_suffix[] = { ".bundle", "" };
110         size_t baselen = path->len;
111         struct stat st;
112         int i;
113
114         for (i = 0; i < ARRAY_SIZE(suffix); i++) {
115                 strbuf_setlen(path, baselen);
116                 strbuf_addstr(path, suffix[i]);
117                 if (stat(path->buf, &st))
118                         continue;
119                 if (S_ISDIR(st.st_mode) && is_git_directory(path->buf)) {
120                         *is_bundle = 0;
121                         return path->buf;
122                 } else if (S_ISREG(st.st_mode) && st.st_size > 8) {
123                         /* Is it a "gitfile"? */
124                         char signature[8];
125                         const char *dst;
126                         int len, fd = open(path->buf, 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                         dst = read_gitfile(path->buf);
134                         if (dst) {
135                                 *is_bundle = 0;
136                                 return dst;
137                         }
138                 }
139         }
140
141         for (i = 0; i < ARRAY_SIZE(bundle_suffix); i++) {
142                 strbuf_setlen(path, baselen);
143                 strbuf_addstr(path, bundle_suffix[i]);
144                 if (!stat(path->buf, &st) && S_ISREG(st.st_mode)) {
145                         *is_bundle = 1;
146                         return path->buf;
147                 }
148         }
149
150         return NULL;
151 }
152
153 static char *get_repo_path(const char *repo, int *is_bundle)
154 {
155         struct strbuf path = STRBUF_INIT;
156         const char *raw;
157         char *canon;
158
159         strbuf_addstr(&path, repo);
160         raw = get_repo_path_1(&path, is_bundle);
161         canon = raw ? xstrdup(absolute_path(raw)) : NULL;
162         strbuf_release(&path);
163         return canon;
164 }
165
166 static char *guess_dir_name(const char *repo, int is_bundle, int is_bare)
167 {
168         const char *end = repo + strlen(repo), *start, *ptr;
169         size_t len;
170         char *dir;
171
172         /*
173          * Skip scheme.
174          */
175         start = strstr(repo, "://");
176         if (start == NULL)
177                 start = repo;
178         else
179                 start += 3;
180
181         /*
182          * Skip authentication data. The stripping does happen
183          * greedily, such that we strip up to the last '@' inside
184          * the host part.
185          */
186         for (ptr = start; ptr < end && !is_dir_sep(*ptr); ptr++) {
187                 if (*ptr == '@')
188                         start = ptr + 1;
189         }
190
191         /*
192          * Strip trailing spaces, slashes and /.git
193          */
194         while (start < end && (is_dir_sep(end[-1]) || isspace(end[-1])))
195                 end--;
196         if (end - start > 5 && is_dir_sep(end[-5]) &&
197             !strncmp(end - 4, ".git", 4)) {
198                 end -= 5;
199                 while (start < end && is_dir_sep(end[-1]))
200                         end--;
201         }
202
203         /*
204          * Strip trailing port number if we've got only a
205          * hostname (that is, there is no dir separator but a
206          * colon). This check is required such that we do not
207          * strip URI's like '/foo/bar:2222.git', which should
208          * result in a dir '2222' being guessed due to backwards
209          * compatibility.
210          */
211         if (memchr(start, '/', end - start) == NULL
212             && memchr(start, ':', end - start) != NULL) {
213                 ptr = end;
214                 while (start < ptr && isdigit(ptr[-1]) && ptr[-1] != ':')
215                         ptr--;
216                 if (start < ptr && ptr[-1] == ':')
217                         end = ptr - 1;
218         }
219
220         /*
221          * Find last component. To remain backwards compatible we
222          * also regard colons as path separators, such that
223          * cloning a repository 'foo:bar.git' would result in a
224          * directory 'bar' being guessed.
225          */
226         ptr = end;
227         while (start < ptr && !is_dir_sep(ptr[-1]) && ptr[-1] != ':')
228                 ptr--;
229         start = ptr;
230
231         /*
232          * Strip .{bundle,git}.
233          */
234         len = end - start;
235         strip_suffix_mem(start, &len, is_bundle ? ".bundle" : ".git");
236
237         if (!len || (len == 1 && *start == '/'))
238                 die(_("No directory name could be guessed.\n"
239                       "Please specify a directory on the command line"));
240
241         if (is_bare)
242                 dir = xstrfmt("%.*s.git", (int)len, start);
243         else
244                 dir = xstrndup(start, len);
245         /*
246          * Replace sequences of 'control' characters and whitespace
247          * with one ascii space, remove leading and trailing spaces.
248          */
249         if (*dir) {
250                 char *out = dir;
251                 int prev_space = 1 /* strip leading whitespace */;
252                 for (end = dir; *end; ++end) {
253                         char ch = *end;
254                         if ((unsigned char)ch < '\x20')
255                                 ch = '\x20';
256                         if (isspace(ch)) {
257                                 if (prev_space)
258                                         continue;
259                                 prev_space = 1;
260                         } else
261                                 prev_space = 0;
262                         *out++ = ch;
263                 }
264                 *out = '\0';
265                 if (out > dir && prev_space)
266                         out[-1] = '\0';
267         }
268         return dir;
269 }
270
271 static void strip_trailing_slashes(char *dir)
272 {
273         char *end = dir + strlen(dir);
274
275         while (dir < end - 1 && is_dir_sep(end[-1]))
276                 end--;
277         *end = '\0';
278 }
279
280 static int add_one_reference(struct string_list_item *item, void *cb_data)
281 {
282         char *ref_git;
283         const char *repo;
284         struct strbuf alternate = STRBUF_INIT;
285
286         /* Beware: read_gitfile(), real_path() and mkpath() return static buffer */
287         ref_git = xstrdup(real_path(item->string));
288
289         repo = read_gitfile(ref_git);
290         if (!repo)
291                 repo = read_gitfile(mkpath("%s/.git", ref_git));
292         if (repo) {
293                 free(ref_git);
294                 ref_git = xstrdup(repo);
295         }
296
297         if (!repo && is_directory(mkpath("%s/.git/objects", ref_git))) {
298                 char *ref_git_git = mkpathdup("%s/.git", ref_git);
299                 free(ref_git);
300                 ref_git = ref_git_git;
301         } else if (!is_directory(mkpath("%s/objects", ref_git))) {
302                 struct strbuf sb = STRBUF_INIT;
303                 if (get_common_dir(&sb, ref_git))
304                         die(_("reference repository '%s' as a linked checkout is not supported yet."),
305                             item->string);
306                 die(_("reference repository '%s' is not a local repository."),
307                     item->string);
308         }
309
310         if (!access(mkpath("%s/shallow", ref_git), F_OK))
311                 die(_("reference repository '%s' is shallow"), item->string);
312
313         if (!access(mkpath("%s/info/grafts", ref_git), F_OK))
314                 die(_("reference repository '%s' is grafted"), item->string);
315
316         strbuf_addf(&alternate, "%s/objects", ref_git);
317         add_to_alternates_file(alternate.buf);
318         strbuf_release(&alternate);
319         free(ref_git);
320         return 0;
321 }
322
323 static void setup_reference(void)
324 {
325         for_each_string_list(&option_reference, add_one_reference, NULL);
326 }
327
328 static void copy_alternates(struct strbuf *src, struct strbuf *dst,
329                             const char *src_repo)
330 {
331         /*
332          * Read from the source objects/info/alternates file
333          * and copy the entries to corresponding file in the
334          * destination repository with add_to_alternates_file().
335          * Both src and dst have "$path/objects/info/alternates".
336          *
337          * Instead of copying bit-for-bit from the original,
338          * we need to append to existing one so that the already
339          * created entry via "clone -s" is not lost, and also
340          * to turn entries with paths relative to the original
341          * absolute, so that they can be used in the new repository.
342          */
343         FILE *in = fopen(src->buf, "r");
344         struct strbuf line = STRBUF_INIT;
345
346         while (strbuf_getline(&line, in) != EOF) {
347                 char *abs_path;
348                 if (!line.len || line.buf[0] == '#')
349                         continue;
350                 if (is_absolute_path(line.buf)) {
351                         add_to_alternates_file(line.buf);
352                         continue;
353                 }
354                 abs_path = mkpathdup("%s/objects/%s", src_repo, line.buf);
355                 normalize_path_copy(abs_path, abs_path);
356                 add_to_alternates_file(abs_path);
357                 free(abs_path);
358         }
359         strbuf_release(&line);
360         fclose(in);
361 }
362
363 static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
364                                    const char *src_repo, int src_baselen)
365 {
366         struct dirent *de;
367         struct stat buf;
368         int src_len, dest_len;
369         DIR *dir;
370
371         dir = opendir(src->buf);
372         if (!dir)
373                 die_errno(_("failed to open '%s'"), src->buf);
374
375         if (mkdir(dest->buf, 0777)) {
376                 if (errno != EEXIST)
377                         die_errno(_("failed to create directory '%s'"), dest->buf);
378                 else if (stat(dest->buf, &buf))
379                         die_errno(_("failed to stat '%s'"), dest->buf);
380                 else if (!S_ISDIR(buf.st_mode))
381                         die(_("%s exists and is not a directory"), dest->buf);
382         }
383
384         strbuf_addch(src, '/');
385         src_len = src->len;
386         strbuf_addch(dest, '/');
387         dest_len = dest->len;
388
389         while ((de = readdir(dir)) != NULL) {
390                 strbuf_setlen(src, src_len);
391                 strbuf_addstr(src, de->d_name);
392                 strbuf_setlen(dest, dest_len);
393                 strbuf_addstr(dest, de->d_name);
394                 if (stat(src->buf, &buf)) {
395                         warning (_("failed to stat %s\n"), src->buf);
396                         continue;
397                 }
398                 if (S_ISDIR(buf.st_mode)) {
399                         if (de->d_name[0] != '.')
400                                 copy_or_link_directory(src, dest,
401                                                        src_repo, src_baselen);
402                         continue;
403                 }
404
405                 /* Files that cannot be copied bit-for-bit... */
406                 if (!strcmp(src->buf + src_baselen, "/info/alternates")) {
407                         copy_alternates(src, dest, src_repo);
408                         continue;
409                 }
410
411                 if (unlink(dest->buf) && errno != ENOENT)
412                         die_errno(_("failed to unlink '%s'"), dest->buf);
413                 if (!option_no_hardlinks) {
414                         if (!link(src->buf, dest->buf))
415                                 continue;
416                         if (option_local > 0)
417                                 die_errno(_("failed to create link '%s'"), dest->buf);
418                         option_no_hardlinks = 1;
419                 }
420                 if (copy_file_with_time(dest->buf, src->buf, 0666))
421                         die_errno(_("failed to copy file to '%s'"), dest->buf);
422         }
423         closedir(dir);
424 }
425
426 static void clone_local(const char *src_repo, const char *dest_repo)
427 {
428         if (option_shared) {
429                 struct strbuf alt = STRBUF_INIT;
430                 strbuf_addf(&alt, "%s/objects", src_repo);
431                 add_to_alternates_file(alt.buf);
432                 strbuf_release(&alt);
433         } else {
434                 struct strbuf src = STRBUF_INIT;
435                 struct strbuf dest = STRBUF_INIT;
436                 get_common_dir(&src, src_repo);
437                 get_common_dir(&dest, dest_repo);
438                 strbuf_addstr(&src, "/objects");
439                 strbuf_addstr(&dest, "/objects");
440                 copy_or_link_directory(&src, &dest, src_repo, src.len);
441                 strbuf_release(&src);
442                 strbuf_release(&dest);
443         }
444
445         if (0 <= option_verbosity)
446                 fprintf(stderr, _("done.\n"));
447 }
448
449 static const char *junk_work_tree;
450 static const char *junk_git_dir;
451 static enum {
452         JUNK_LEAVE_NONE,
453         JUNK_LEAVE_REPO,
454         JUNK_LEAVE_ALL
455 } junk_mode = JUNK_LEAVE_NONE;
456
457 static const char junk_leave_repo_msg[] =
458 N_("Clone succeeded, but checkout failed.\n"
459    "You can inspect what was checked out with 'git status'\n"
460    "and retry the checkout with 'git checkout -f HEAD'\n");
461
462 static void remove_junk(void)
463 {
464         struct strbuf sb = STRBUF_INIT;
465
466         switch (junk_mode) {
467         case JUNK_LEAVE_REPO:
468                 warning("%s", _(junk_leave_repo_msg));
469                 /* fall-through */
470         case JUNK_LEAVE_ALL:
471                 return;
472         default:
473                 /* proceed to removal */
474                 break;
475         }
476
477         if (junk_git_dir) {
478                 strbuf_addstr(&sb, junk_git_dir);
479                 remove_dir_recursively(&sb, 0);
480                 strbuf_reset(&sb);
481         }
482         if (junk_work_tree) {
483                 strbuf_addstr(&sb, junk_work_tree);
484                 remove_dir_recursively(&sb, 0);
485                 strbuf_reset(&sb);
486         }
487 }
488
489 static void remove_junk_on_signal(int signo)
490 {
491         remove_junk();
492         sigchain_pop(signo);
493         raise(signo);
494 }
495
496 static struct ref *find_remote_branch(const struct ref *refs, const char *branch)
497 {
498         struct ref *ref;
499         struct strbuf head = STRBUF_INIT;
500         strbuf_addstr(&head, "refs/heads/");
501         strbuf_addstr(&head, branch);
502         ref = find_ref_by_name(refs, head.buf);
503         strbuf_release(&head);
504
505         if (ref)
506                 return ref;
507
508         strbuf_addstr(&head, "refs/tags/");
509         strbuf_addstr(&head, branch);
510         ref = find_ref_by_name(refs, head.buf);
511         strbuf_release(&head);
512
513         return ref;
514 }
515
516 static struct ref *wanted_peer_refs(const struct ref *refs,
517                 struct refspec *refspec)
518 {
519         struct ref *head = copy_ref(find_ref_by_name(refs, "HEAD"));
520         struct ref *local_refs = head;
521         struct ref **tail = head ? &head->next : &local_refs;
522
523         if (option_single_branch) {
524                 struct ref *remote_head = NULL;
525
526                 if (!option_branch)
527                         remote_head = guess_remote_head(head, refs, 0);
528                 else {
529                         local_refs = NULL;
530                         tail = &local_refs;
531                         remote_head = copy_ref(find_remote_branch(refs, option_branch));
532                 }
533
534                 if (!remote_head && option_branch)
535                         warning(_("Could not find remote branch %s to clone."),
536                                 option_branch);
537                 else {
538                         get_fetch_map(remote_head, refspec, &tail, 0);
539
540                         /* if --branch=tag, pull the requested tag explicitly */
541                         get_fetch_map(remote_head, tag_refspec, &tail, 0);
542                 }
543         } else
544                 get_fetch_map(refs, refspec, &tail, 0);
545
546         if (!option_mirror && !option_single_branch)
547                 get_fetch_map(refs, tag_refspec, &tail, 0);
548
549         return local_refs;
550 }
551
552 static void write_remote_refs(const struct ref *local_refs)
553 {
554         const struct ref *r;
555
556         struct ref_transaction *t;
557         struct strbuf err = STRBUF_INIT;
558
559         t = ref_transaction_begin(&err);
560         if (!t)
561                 die("%s", err.buf);
562
563         for (r = local_refs; r; r = r->next) {
564                 if (!r->peer_ref)
565                         continue;
566                 if (ref_transaction_create(t, r->peer_ref->name, r->old_oid.hash,
567                                            0, NULL, &err))
568                         die("%s", err.buf);
569         }
570
571         if (initial_ref_transaction_commit(t, &err))
572                 die("%s", err.buf);
573
574         strbuf_release(&err);
575         ref_transaction_free(t);
576 }
577
578 static void write_followtags(const struct ref *refs, const char *msg)
579 {
580         const struct ref *ref;
581         for (ref = refs; ref; ref = ref->next) {
582                 if (!starts_with(ref->name, "refs/tags/"))
583                         continue;
584                 if (ends_with(ref->name, "^{}"))
585                         continue;
586                 if (!has_object_file(&ref->old_oid))
587                         continue;
588                 update_ref(msg, ref->name, ref->old_oid.hash,
589                            NULL, 0, UPDATE_REFS_DIE_ON_ERR);
590         }
591 }
592
593 static int iterate_ref_map(void *cb_data, unsigned char sha1[20])
594 {
595         struct ref **rm = cb_data;
596         struct ref *ref = *rm;
597
598         /*
599          * Skip anything missing a peer_ref, which we are not
600          * actually going to write a ref for.
601          */
602         while (ref && !ref->peer_ref)
603                 ref = ref->next;
604         /* Returning -1 notes "end of list" to the caller. */
605         if (!ref)
606                 return -1;
607
608         hashcpy(sha1, ref->old_oid.hash);
609         *rm = ref->next;
610         return 0;
611 }
612
613 static void update_remote_refs(const struct ref *refs,
614                                const struct ref *mapped_refs,
615                                const struct ref *remote_head_points_at,
616                                const char *branch_top,
617                                const char *msg,
618                                struct transport *transport,
619                                int check_connectivity)
620 {
621         const struct ref *rm = mapped_refs;
622
623         if (check_connectivity) {
624                 if (transport->progress)
625                         fprintf(stderr, _("Checking connectivity... "));
626                 if (check_everything_connected_with_transport(iterate_ref_map,
627                                                               0, &rm, transport))
628                         die(_("remote did not send all necessary objects"));
629                 if (transport->progress)
630                         fprintf(stderr, _("done.\n"));
631         }
632
633         if (refs) {
634                 write_remote_refs(mapped_refs);
635                 if (option_single_branch)
636                         write_followtags(refs, msg);
637         }
638
639         if (remote_head_points_at && !option_bare) {
640                 struct strbuf head_ref = STRBUF_INIT;
641                 strbuf_addstr(&head_ref, branch_top);
642                 strbuf_addstr(&head_ref, "HEAD");
643                 if (create_symref(head_ref.buf,
644                                   remote_head_points_at->peer_ref->name,
645                                   msg) < 0)
646                         die(_("unable to update %s"), head_ref.buf);
647                 strbuf_release(&head_ref);
648         }
649 }
650
651 static void update_head(const struct ref *our, const struct ref *remote,
652                         const char *msg)
653 {
654         const char *head;
655         if (our && skip_prefix(our->name, "refs/heads/", &head)) {
656                 /* Local default branch link */
657                 if (create_symref("HEAD", our->name, NULL) < 0)
658                         die(_("unable to update HEAD"));
659                 if (!option_bare) {
660                         update_ref(msg, "HEAD", our->old_oid.hash, NULL, 0,
661                                    UPDATE_REFS_DIE_ON_ERR);
662                         install_branch_config(0, head, option_origin, our->name);
663                 }
664         } else if (our) {
665                 struct commit *c = lookup_commit_reference(our->old_oid.hash);
666                 /* --branch specifies a non-branch (i.e. tags), detach HEAD */
667                 update_ref(msg, "HEAD", c->object.oid.hash,
668                            NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
669         } else if (remote) {
670                 /*
671                  * We know remote HEAD points to a non-branch, or
672                  * HEAD points to a branch but we don't know which one.
673                  * Detach HEAD in all these cases.
674                  */
675                 update_ref(msg, "HEAD", remote->old_oid.hash,
676                            NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
677         }
678 }
679
680 static int checkout(void)
681 {
682         unsigned char sha1[20];
683         char *head;
684         struct lock_file *lock_file;
685         struct unpack_trees_options opts;
686         struct tree *tree;
687         struct tree_desc t;
688         int err = 0;
689
690         if (option_no_checkout)
691                 return 0;
692
693         head = resolve_refdup("HEAD", RESOLVE_REF_READING, sha1, NULL);
694         if (!head) {
695                 warning(_("remote HEAD refers to nonexistent ref, "
696                           "unable to checkout.\n"));
697                 return 0;
698         }
699         if (!strcmp(head, "HEAD")) {
700                 if (advice_detached_head)
701                         detach_advice(sha1_to_hex(sha1));
702         } else {
703                 if (!starts_with(head, "refs/heads/"))
704                         die(_("HEAD not found below refs/heads!"));
705         }
706         free(head);
707
708         /* We need to be in the new work tree for the checkout */
709         setup_work_tree();
710
711         lock_file = xcalloc(1, sizeof(struct lock_file));
712         hold_locked_index(lock_file, 1);
713
714         memset(&opts, 0, sizeof opts);
715         opts.update = 1;
716         opts.merge = 1;
717         opts.fn = oneway_merge;
718         opts.verbose_update = (option_verbosity >= 0);
719         opts.src_index = &the_index;
720         opts.dst_index = &the_index;
721
722         tree = parse_tree_indirect(sha1);
723         parse_tree(tree);
724         init_tree_desc(&t, tree->buffer, tree->size);
725         if (unpack_trees(1, &t, &opts) < 0)
726                 die(_("unable to checkout working tree"));
727
728         if (write_locked_index(&the_index, lock_file, COMMIT_LOCK))
729                 die(_("unable to write new index file"));
730
731         err |= run_hook_le(NULL, "post-checkout", sha1_to_hex(null_sha1),
732                            sha1_to_hex(sha1), "1", NULL);
733
734         if (!err && option_recursive) {
735                 struct argv_array args = ARGV_ARRAY_INIT;
736                 argv_array_pushl(&args, "submodule", "update", "--init", "--recursive", NULL);
737
738                 if (max_jobs != -1)
739                         argv_array_pushf(&args, "--jobs=%d", max_jobs);
740
741                 err = run_command_v_opt(args.argv, RUN_GIT_CMD);
742                 argv_array_clear(&args);
743         }
744
745         return err;
746 }
747
748 static int write_one_config(const char *key, const char *value, void *data)
749 {
750         return git_config_set_multivar_gently(key, value ? value : "true", "^$", 0);
751 }
752
753 static void write_config(struct string_list *config)
754 {
755         int i;
756
757         for (i = 0; i < config->nr; i++) {
758                 if (git_config_parse_parameter(config->items[i].string,
759                                                write_one_config, NULL) < 0)
760                         die(_("unable to write parameters to config file"));
761         }
762 }
763
764 static void write_refspec_config(const char *src_ref_prefix,
765                 const struct ref *our_head_points_at,
766                 const struct ref *remote_head_points_at,
767                 struct strbuf *branch_top)
768 {
769         struct strbuf key = STRBUF_INIT;
770         struct strbuf value = STRBUF_INIT;
771
772         if (option_mirror || !option_bare) {
773                 if (option_single_branch && !option_mirror) {
774                         if (option_branch) {
775                                 if (starts_with(our_head_points_at->name, "refs/tags/"))
776                                         strbuf_addf(&value, "+%s:%s", our_head_points_at->name,
777                                                 our_head_points_at->name);
778                                 else
779                                         strbuf_addf(&value, "+%s:%s%s", our_head_points_at->name,
780                                                 branch_top->buf, option_branch);
781                         } else if (remote_head_points_at) {
782                                 const char *head = remote_head_points_at->name;
783                                 if (!skip_prefix(head, "refs/heads/", &head))
784                                         die("BUG: remote HEAD points at non-head?");
785
786                                 strbuf_addf(&value, "+%s:%s%s", remote_head_points_at->name,
787                                                 branch_top->buf, head);
788                         }
789                         /*
790                          * otherwise, the next "git fetch" will
791                          * simply fetch from HEAD without updating
792                          * any remote-tracking branch, which is what
793                          * we want.
794                          */
795                 } else {
796                         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top->buf);
797                 }
798                 /* Configure the remote */
799                 if (value.len) {
800                         strbuf_addf(&key, "remote.%s.fetch", option_origin);
801                         git_config_set_multivar(key.buf, value.buf, "^$", 0);
802                         strbuf_reset(&key);
803
804                         if (option_mirror) {
805                                 strbuf_addf(&key, "remote.%s.mirror", option_origin);
806                                 git_config_set(key.buf, "true");
807                                 strbuf_reset(&key);
808                         }
809                 }
810         }
811
812         strbuf_release(&key);
813         strbuf_release(&value);
814 }
815
816 static void dissociate_from_references(void)
817 {
818         static const char* argv[] = { "repack", "-a", "-d", NULL };
819         char *alternates = git_pathdup("objects/info/alternates");
820
821         if (!access(alternates, F_OK)) {
822                 if (run_command_v_opt(argv, RUN_GIT_CMD|RUN_COMMAND_NO_STDIN))
823                         die(_("cannot repack to clean up"));
824                 if (unlink(alternates) && errno != ENOENT)
825                         die_errno(_("cannot unlink temporary alternates file"));
826         }
827         free(alternates);
828 }
829
830 int cmd_clone(int argc, const char **argv, const char *prefix)
831 {
832         int is_bundle = 0, is_local;
833         struct stat buf;
834         const char *repo_name, *repo, *work_tree, *git_dir;
835         char *path, *dir;
836         int dest_exists;
837         const struct ref *refs, *remote_head;
838         const struct ref *remote_head_points_at;
839         const struct ref *our_head_points_at;
840         struct ref *mapped_refs;
841         const struct ref *ref;
842         struct strbuf key = STRBUF_INIT, value = STRBUF_INIT;
843         struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
844         struct transport *transport = NULL;
845         const char *src_ref_prefix = "refs/heads/";
846         struct remote *remote;
847         int err = 0, complete_refs_before_fetch = 1;
848
849         struct refspec *refspec;
850         const char *fetch_pattern;
851
852         packet_trace_identity("clone");
853         argc = parse_options(argc, argv, prefix, builtin_clone_options,
854                              builtin_clone_usage, 0);
855
856         if (argc > 2)
857                 usage_msg_opt(_("Too many arguments."),
858                         builtin_clone_usage, builtin_clone_options);
859
860         if (argc == 0)
861                 usage_msg_opt(_("You must specify a repository to clone."),
862                         builtin_clone_usage, builtin_clone_options);
863
864         if (option_single_branch == -1)
865                 option_single_branch = option_depth ? 1 : 0;
866
867         if (option_mirror)
868                 option_bare = 1;
869
870         if (option_bare) {
871                 if (option_origin)
872                         die(_("--bare and --origin %s options are incompatible."),
873                             option_origin);
874                 if (real_git_dir)
875                         die(_("--bare and --separate-git-dir are incompatible."));
876                 option_no_checkout = 1;
877         }
878
879         if (!option_origin)
880                 option_origin = "origin";
881
882         repo_name = argv[0];
883
884         path = get_repo_path(repo_name, &is_bundle);
885         if (path)
886                 repo = xstrdup(absolute_path(repo_name));
887         else if (!strchr(repo_name, ':'))
888                 die(_("repository '%s' does not exist"), repo_name);
889         else
890                 repo = repo_name;
891
892         /* no need to be strict, transport_set_option() will validate it again */
893         if (option_depth && atoi(option_depth) < 1)
894                 die(_("depth %s is not a positive number"), option_depth);
895
896         if (argc == 2)
897                 dir = xstrdup(argv[1]);
898         else
899                 dir = guess_dir_name(repo_name, is_bundle, option_bare);
900         strip_trailing_slashes(dir);
901
902         dest_exists = !stat(dir, &buf);
903         if (dest_exists && !is_empty_dir(dir))
904                 die(_("destination path '%s' already exists and is not "
905                         "an empty directory."), dir);
906
907         strbuf_addf(&reflog_msg, "clone: from %s", repo);
908
909         if (option_bare)
910                 work_tree = NULL;
911         else {
912                 work_tree = getenv("GIT_WORK_TREE");
913                 if (work_tree && !stat(work_tree, &buf))
914                         die(_("working tree '%s' already exists."), work_tree);
915         }
916
917         if (option_bare || work_tree)
918                 git_dir = xstrdup(dir);
919         else {
920                 work_tree = dir;
921                 git_dir = mkpathdup("%s/.git", dir);
922         }
923
924         atexit(remove_junk);
925         sigchain_push_common(remove_junk_on_signal);
926
927         if (!option_bare) {
928                 if (safe_create_leading_directories_const(work_tree) < 0)
929                         die_errno(_("could not create leading directories of '%s'"),
930                                   work_tree);
931                 if (!dest_exists && mkdir(work_tree, 0777))
932                         die_errno(_("could not create work tree dir '%s'"),
933                                   work_tree);
934                 junk_work_tree = work_tree;
935                 set_git_work_tree(work_tree);
936         }
937
938         junk_git_dir = git_dir;
939         if (safe_create_leading_directories_const(git_dir) < 0)
940                 die(_("could not create leading directories of '%s'"), git_dir);
941
942         set_git_dir_init(git_dir, real_git_dir, 0);
943         if (real_git_dir) {
944                 git_dir = real_git_dir;
945                 junk_git_dir = real_git_dir;
946         }
947
948         if (0 <= option_verbosity) {
949                 if (option_bare)
950                         fprintf(stderr, _("Cloning into bare repository '%s'...\n"), dir);
951                 else
952                         fprintf(stderr, _("Cloning into '%s'...\n"), dir);
953         }
954         init_db(option_template, INIT_DB_QUIET);
955         write_config(&option_config);
956
957         git_config(git_default_config, NULL);
958
959         if (option_bare) {
960                 if (option_mirror)
961                         src_ref_prefix = "refs/";
962                 strbuf_addstr(&branch_top, src_ref_prefix);
963
964                 git_config_set("core.bare", "true");
965         } else {
966                 strbuf_addf(&branch_top, "refs/remotes/%s/", option_origin);
967         }
968
969         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top.buf);
970         strbuf_addf(&key, "remote.%s.url", option_origin);
971         git_config_set(key.buf, repo);
972         strbuf_reset(&key);
973
974         if (option_reference.nr)
975                 setup_reference();
976
977         fetch_pattern = value.buf;
978         refspec = parse_fetch_refspec(1, &fetch_pattern);
979
980         strbuf_reset(&value);
981
982         remote = remote_get(option_origin);
983         transport = transport_get(remote, remote->url[0]);
984         transport_set_verbosity(transport, option_verbosity, option_progress);
985         transport->family = family;
986
987         path = get_repo_path(remote->url[0], &is_bundle);
988         is_local = option_local != 0 && path && !is_bundle;
989         if (is_local) {
990                 if (option_depth)
991                         warning(_("--depth is ignored in local clones; use file:// instead."));
992                 if (!access(mkpath("%s/shallow", path), F_OK)) {
993                         if (option_local > 0)
994                                 warning(_("source repository is shallow, ignoring --local"));
995                         is_local = 0;
996                 }
997         }
998         if (option_local > 0 && !is_local)
999                 warning(_("--local is ignored"));
1000         transport->cloning = 1;
1001
1002         if (!transport->get_refs_list || (!is_local && !transport->fetch))
1003                 die(_("Don't know how to clone %s"), transport->url);
1004
1005         transport_set_option(transport, TRANS_OPT_KEEP, "yes");
1006
1007         if (option_depth)
1008                 transport_set_option(transport, TRANS_OPT_DEPTH,
1009                                      option_depth);
1010         if (option_single_branch)
1011                 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
1012
1013         if (option_upload_pack)
1014                 transport_set_option(transport, TRANS_OPT_UPLOADPACK,
1015                                      option_upload_pack);
1016
1017         if (transport->smart_options && !option_depth)
1018                 transport->smart_options->check_self_contained_and_connected = 1;
1019
1020         refs = transport_get_remote_refs(transport);
1021
1022         if (refs) {
1023                 mapped_refs = wanted_peer_refs(refs, refspec);
1024                 /*
1025                  * transport_get_remote_refs() may return refs with null sha-1
1026                  * in mapped_refs (see struct transport->get_refs_list
1027                  * comment). In that case we need fetch it early because
1028                  * remote_head code below relies on it.
1029                  *
1030                  * for normal clones, transport_get_remote_refs() should
1031                  * return reliable ref set, we can delay cloning until after
1032                  * remote HEAD check.
1033                  */
1034                 for (ref = refs; ref; ref = ref->next)
1035                         if (is_null_oid(&ref->old_oid)) {
1036                                 complete_refs_before_fetch = 0;
1037                                 break;
1038                         }
1039
1040                 if (!is_local && !complete_refs_before_fetch)
1041                         transport_fetch_refs(transport, mapped_refs);
1042
1043                 remote_head = find_ref_by_name(refs, "HEAD");
1044                 remote_head_points_at =
1045                         guess_remote_head(remote_head, mapped_refs, 0);
1046
1047                 if (option_branch) {
1048                         our_head_points_at =
1049                                 find_remote_branch(mapped_refs, option_branch);
1050
1051                         if (!our_head_points_at)
1052                                 die(_("Remote branch %s not found in upstream %s"),
1053                                     option_branch, option_origin);
1054                 }
1055                 else
1056                         our_head_points_at = remote_head_points_at;
1057         }
1058         else {
1059                 if (option_branch)
1060                         die(_("Remote branch %s not found in upstream %s"),
1061                                         option_branch, option_origin);
1062
1063                 warning(_("You appear to have cloned an empty repository."));
1064                 mapped_refs = NULL;
1065                 our_head_points_at = NULL;
1066                 remote_head_points_at = NULL;
1067                 remote_head = NULL;
1068                 option_no_checkout = 1;
1069                 if (!option_bare)
1070                         install_branch_config(0, "master", option_origin,
1071                                               "refs/heads/master");
1072         }
1073
1074         write_refspec_config(src_ref_prefix, our_head_points_at,
1075                         remote_head_points_at, &branch_top);
1076
1077         if (is_local)
1078                 clone_local(path, git_dir);
1079         else if (refs && complete_refs_before_fetch)
1080                 transport_fetch_refs(transport, mapped_refs);
1081
1082         update_remote_refs(refs, mapped_refs, remote_head_points_at,
1083                            branch_top.buf, reflog_msg.buf, transport, !is_local);
1084
1085         update_head(our_head_points_at, remote_head, reflog_msg.buf);
1086
1087         transport_unlock_pack(transport);
1088         transport_disconnect(transport);
1089
1090         if (option_dissociate) {
1091                 close_all_packs();
1092                 dissociate_from_references();
1093         }
1094
1095         junk_mode = JUNK_LEAVE_REPO;
1096         err = checkout();
1097
1098         strbuf_release(&reflog_msg);
1099         strbuf_release(&branch_top);
1100         strbuf_release(&key);
1101         strbuf_release(&value);
1102         junk_mode = JUNK_LEAVE_ALL;
1103
1104         free(refspec);
1105         return err;
1106 }