Merge branch 'bc/object-id'
[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;
43 static int option_no_tags;
44 static int option_shallow_submodules;
45 static int deepen;
46 static char *option_template, *option_depth, *option_since;
47 static char *option_origin = NULL;
48 static char *option_branch = NULL;
49 static struct string_list option_not = STRING_LIST_INIT_NODUP;
50 static const char *real_git_dir;
51 static char *option_upload_pack = "git-upload-pack";
52 static int option_verbosity;
53 static int option_progress = -1;
54 static enum transport_family family;
55 static struct string_list option_config = STRING_LIST_INIT_NODUP;
56 static struct string_list option_required_reference = STRING_LIST_INIT_NODUP;
57 static struct string_list option_optional_reference = STRING_LIST_INIT_NODUP;
58 static int option_dissociate;
59 static int max_jobs = -1;
60 static struct string_list option_recurse_submodules = STRING_LIST_INIT_NODUP;
61
62 static int recurse_submodules_cb(const struct option *opt,
63                                  const char *arg, int unset)
64 {
65         if (unset)
66                 string_list_clear((struct string_list *)opt->value, 0);
67         else if (arg)
68                 string_list_append((struct string_list *)opt->value, arg);
69         else
70                 string_list_append((struct string_list *)opt->value,
71                                    (const char *)opt->defval);
72
73         return 0;
74 }
75
76 static struct option builtin_clone_options[] = {
77         OPT__VERBOSITY(&option_verbosity),
78         OPT_BOOL(0, "progress", &option_progress,
79                  N_("force progress reporting")),
80         OPT_BOOL('n', "no-checkout", &option_no_checkout,
81                  N_("don't create a checkout")),
82         OPT_BOOL(0, "bare", &option_bare, N_("create a bare repository")),
83         OPT_HIDDEN_BOOL(0, "naked", &option_bare,
84                         N_("create a bare repository")),
85         OPT_BOOL(0, "mirror", &option_mirror,
86                  N_("create a mirror repository (implies bare)")),
87         OPT_BOOL('l', "local", &option_local,
88                 N_("to clone from a local repository")),
89         OPT_BOOL(0, "no-hardlinks", &option_no_hardlinks,
90                     N_("don't use local hardlinks, always copy")),
91         OPT_BOOL('s', "shared", &option_shared,
92                     N_("setup as shared repository")),
93         { OPTION_CALLBACK, 0, "recursive", &option_recurse_submodules,
94           N_("pathspec"), N_("initialize submodules in the clone"),
95           PARSE_OPT_OPTARG | PARSE_OPT_HIDDEN, recurse_submodules_cb,
96           (intptr_t)"." },
97         { OPTION_CALLBACK, 0, "recurse-submodules", &option_recurse_submodules,
98           N_("pathspec"), N_("initialize submodules in the clone"),
99           PARSE_OPT_OPTARG, recurse_submodules_cb, (intptr_t)"." },
100         OPT_INTEGER('j', "jobs", &max_jobs,
101                     N_("number of submodules cloned in parallel")),
102         OPT_STRING(0, "template", &option_template, N_("template-directory"),
103                    N_("directory from which templates will be used")),
104         OPT_STRING_LIST(0, "reference", &option_required_reference, N_("repo"),
105                         N_("reference repository")),
106         OPT_STRING_LIST(0, "reference-if-able", &option_optional_reference,
107                         N_("repo"), N_("reference repository")),
108         OPT_BOOL(0, "dissociate", &option_dissociate,
109                  N_("use --reference only while cloning")),
110         OPT_STRING('o', "origin", &option_origin, N_("name"),
111                    N_("use <name> instead of 'origin' to track upstream")),
112         OPT_STRING('b', "branch", &option_branch, N_("branch"),
113                    N_("checkout <branch> instead of the remote's HEAD")),
114         OPT_STRING('u', "upload-pack", &option_upload_pack, N_("path"),
115                    N_("path to git-upload-pack on the remote")),
116         OPT_STRING(0, "depth", &option_depth, N_("depth"),
117                     N_("create a shallow clone of that depth")),
118         OPT_STRING(0, "shallow-since", &option_since, N_("time"),
119                     N_("create a shallow clone since a specific time")),
120         OPT_STRING_LIST(0, "shallow-exclude", &option_not, N_("revision"),
121                         N_("deepen history of shallow clone, excluding rev")),
122         OPT_BOOL(0, "single-branch", &option_single_branch,
123                     N_("clone only one branch, HEAD or --branch")),
124         OPT_BOOL(0, "no-tags", &option_no_tags,
125                  N_("don't clone any tags, and make later fetches not to follow them")),
126         OPT_BOOL(0, "shallow-submodules", &option_shallow_submodules,
127                     N_("any cloned submodules will be shallow")),
128         OPT_STRING(0, "separate-git-dir", &real_git_dir, N_("gitdir"),
129                    N_("separate git dir from working tree")),
130         OPT_STRING_LIST('c', "config", &option_config, N_("key=value"),
131                         N_("set config inside the new repository")),
132         OPT_SET_INT('4', "ipv4", &family, N_("use IPv4 addresses only"),
133                         TRANSPORT_FAMILY_IPV4),
134         OPT_SET_INT('6', "ipv6", &family, N_("use IPv6 addresses only"),
135                         TRANSPORT_FAMILY_IPV6),
136         OPT_END()
137 };
138
139 static const char *get_repo_path_1(struct strbuf *path, int *is_bundle)
140 {
141         static char *suffix[] = { "/.git", "", ".git/.git", ".git" };
142         static char *bundle_suffix[] = { ".bundle", "" };
143         size_t baselen = path->len;
144         struct stat st;
145         int i;
146
147         for (i = 0; i < ARRAY_SIZE(suffix); i++) {
148                 strbuf_setlen(path, baselen);
149                 strbuf_addstr(path, suffix[i]);
150                 if (stat(path->buf, &st))
151                         continue;
152                 if (S_ISDIR(st.st_mode) && is_git_directory(path->buf)) {
153                         *is_bundle = 0;
154                         return path->buf;
155                 } else if (S_ISREG(st.st_mode) && st.st_size > 8) {
156                         /* Is it a "gitfile"? */
157                         char signature[8];
158                         const char *dst;
159                         int len, fd = open(path->buf, O_RDONLY);
160                         if (fd < 0)
161                                 continue;
162                         len = read_in_full(fd, signature, 8);
163                         close(fd);
164                         if (len != 8 || strncmp(signature, "gitdir: ", 8))
165                                 continue;
166                         dst = read_gitfile(path->buf);
167                         if (dst) {
168                                 *is_bundle = 0;
169                                 return dst;
170                         }
171                 }
172         }
173
174         for (i = 0; i < ARRAY_SIZE(bundle_suffix); i++) {
175                 strbuf_setlen(path, baselen);
176                 strbuf_addstr(path, bundle_suffix[i]);
177                 if (!stat(path->buf, &st) && S_ISREG(st.st_mode)) {
178                         *is_bundle = 1;
179                         return path->buf;
180                 }
181         }
182
183         return NULL;
184 }
185
186 static char *get_repo_path(const char *repo, int *is_bundle)
187 {
188         struct strbuf path = STRBUF_INIT;
189         const char *raw;
190         char *canon;
191
192         strbuf_addstr(&path, repo);
193         raw = get_repo_path_1(&path, is_bundle);
194         canon = raw ? absolute_pathdup(raw) : NULL;
195         strbuf_release(&path);
196         return canon;
197 }
198
199 static char *guess_dir_name(const char *repo, int is_bundle, int is_bare)
200 {
201         const char *end = repo + strlen(repo), *start, *ptr;
202         size_t len;
203         char *dir;
204
205         /*
206          * Skip scheme.
207          */
208         start = strstr(repo, "://");
209         if (start == NULL)
210                 start = repo;
211         else
212                 start += 3;
213
214         /*
215          * Skip authentication data. The stripping does happen
216          * greedily, such that we strip up to the last '@' inside
217          * the host part.
218          */
219         for (ptr = start; ptr < end && !is_dir_sep(*ptr); ptr++) {
220                 if (*ptr == '@')
221                         start = ptr + 1;
222         }
223
224         /*
225          * Strip trailing spaces, slashes and /.git
226          */
227         while (start < end && (is_dir_sep(end[-1]) || isspace(end[-1])))
228                 end--;
229         if (end - start > 5 && is_dir_sep(end[-5]) &&
230             !strncmp(end - 4, ".git", 4)) {
231                 end -= 5;
232                 while (start < end && is_dir_sep(end[-1]))
233                         end--;
234         }
235
236         /*
237          * Strip trailing port number if we've got only a
238          * hostname (that is, there is no dir separator but a
239          * colon). This check is required such that we do not
240          * strip URI's like '/foo/bar:2222.git', which should
241          * result in a dir '2222' being guessed due to backwards
242          * compatibility.
243          */
244         if (memchr(start, '/', end - start) == NULL
245             && memchr(start, ':', end - start) != NULL) {
246                 ptr = end;
247                 while (start < ptr && isdigit(ptr[-1]) && ptr[-1] != ':')
248                         ptr--;
249                 if (start < ptr && ptr[-1] == ':')
250                         end = ptr - 1;
251         }
252
253         /*
254          * Find last component. To remain backwards compatible we
255          * also regard colons as path separators, such that
256          * cloning a repository 'foo:bar.git' would result in a
257          * directory 'bar' being guessed.
258          */
259         ptr = end;
260         while (start < ptr && !is_dir_sep(ptr[-1]) && ptr[-1] != ':')
261                 ptr--;
262         start = ptr;
263
264         /*
265          * Strip .{bundle,git}.
266          */
267         len = end - start;
268         strip_suffix_mem(start, &len, is_bundle ? ".bundle" : ".git");
269
270         if (!len || (len == 1 && *start == '/'))
271                 die(_("No directory name could be guessed.\n"
272                       "Please specify a directory on the command line"));
273
274         if (is_bare)
275                 dir = xstrfmt("%.*s.git", (int)len, start);
276         else
277                 dir = xstrndup(start, len);
278         /*
279          * Replace sequences of 'control' characters and whitespace
280          * with one ascii space, remove leading and trailing spaces.
281          */
282         if (*dir) {
283                 char *out = dir;
284                 int prev_space = 1 /* strip leading whitespace */;
285                 for (end = dir; *end; ++end) {
286                         char ch = *end;
287                         if ((unsigned char)ch < '\x20')
288                                 ch = '\x20';
289                         if (isspace(ch)) {
290                                 if (prev_space)
291                                         continue;
292                                 prev_space = 1;
293                         } else
294                                 prev_space = 0;
295                         *out++ = ch;
296                 }
297                 *out = '\0';
298                 if (out > dir && prev_space)
299                         out[-1] = '\0';
300         }
301         return dir;
302 }
303
304 static void strip_trailing_slashes(char *dir)
305 {
306         char *end = dir + strlen(dir);
307
308         while (dir < end - 1 && is_dir_sep(end[-1]))
309                 end--;
310         *end = '\0';
311 }
312
313 static int add_one_reference(struct string_list_item *item, void *cb_data)
314 {
315         struct strbuf err = STRBUF_INIT;
316         int *required = cb_data;
317         char *ref_git = compute_alternate_path(item->string, &err);
318
319         if (!ref_git) {
320                 if (*required)
321                         die("%s", err.buf);
322                 else
323                         fprintf(stderr,
324                                 _("info: Could not add alternate for '%s': %s\n"),
325                                 item->string, err.buf);
326         } else {
327                 struct strbuf sb = STRBUF_INIT;
328                 strbuf_addf(&sb, "%s/objects", ref_git);
329                 add_to_alternates_file(sb.buf);
330                 strbuf_release(&sb);
331         }
332
333         strbuf_release(&err);
334         free(ref_git);
335         return 0;
336 }
337
338 static void setup_reference(void)
339 {
340         int required = 1;
341         for_each_string_list(&option_required_reference,
342                              add_one_reference, &required);
343         required = 0;
344         for_each_string_list(&option_optional_reference,
345                              add_one_reference, &required);
346 }
347
348 static void copy_alternates(struct strbuf *src, struct strbuf *dst,
349                             const char *src_repo)
350 {
351         /*
352          * Read from the source objects/info/alternates file
353          * and copy the entries to corresponding file in the
354          * destination repository with add_to_alternates_file().
355          * Both src and dst have "$path/objects/info/alternates".
356          *
357          * Instead of copying bit-for-bit from the original,
358          * we need to append to existing one so that the already
359          * created entry via "clone -s" is not lost, and also
360          * to turn entries with paths relative to the original
361          * absolute, so that they can be used in the new repository.
362          */
363         FILE *in = fopen(src->buf, "r");
364         struct strbuf line = STRBUF_INIT;
365
366         while (strbuf_getline(&line, in) != EOF) {
367                 char *abs_path;
368                 if (!line.len || line.buf[0] == '#')
369                         continue;
370                 if (is_absolute_path(line.buf)) {
371                         add_to_alternates_file(line.buf);
372                         continue;
373                 }
374                 abs_path = mkpathdup("%s/objects/%s", src_repo, line.buf);
375                 if (!normalize_path_copy(abs_path, abs_path))
376                         add_to_alternates_file(abs_path);
377                 else
378                         warning("skipping invalid relative alternate: %s/%s",
379                                 src_repo, line.buf);
380                 free(abs_path);
381         }
382         strbuf_release(&line);
383         fclose(in);
384 }
385
386 static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
387                                    const char *src_repo, int src_baselen)
388 {
389         struct dirent *de;
390         struct stat buf;
391         int src_len, dest_len;
392         DIR *dir;
393
394         dir = opendir(src->buf);
395         if (!dir)
396                 die_errno(_("failed to open '%s'"), src->buf);
397
398         if (mkdir(dest->buf, 0777)) {
399                 if (errno != EEXIST)
400                         die_errno(_("failed to create directory '%s'"), dest->buf);
401                 else if (stat(dest->buf, &buf))
402                         die_errno(_("failed to stat '%s'"), dest->buf);
403                 else if (!S_ISDIR(buf.st_mode))
404                         die(_("%s exists and is not a directory"), dest->buf);
405         }
406
407         strbuf_addch(src, '/');
408         src_len = src->len;
409         strbuf_addch(dest, '/');
410         dest_len = dest->len;
411
412         while ((de = readdir(dir)) != NULL) {
413                 strbuf_setlen(src, src_len);
414                 strbuf_addstr(src, de->d_name);
415                 strbuf_setlen(dest, dest_len);
416                 strbuf_addstr(dest, de->d_name);
417                 if (stat(src->buf, &buf)) {
418                         warning (_("failed to stat %s\n"), src->buf);
419                         continue;
420                 }
421                 if (S_ISDIR(buf.st_mode)) {
422                         if (de->d_name[0] != '.')
423                                 copy_or_link_directory(src, dest,
424                                                        src_repo, src_baselen);
425                         continue;
426                 }
427
428                 /* Files that cannot be copied bit-for-bit... */
429                 if (!strcmp(src->buf + src_baselen, "/info/alternates")) {
430                         copy_alternates(src, dest, src_repo);
431                         continue;
432                 }
433
434                 if (unlink(dest->buf) && errno != ENOENT)
435                         die_errno(_("failed to unlink '%s'"), dest->buf);
436                 if (!option_no_hardlinks) {
437                         if (!link(src->buf, dest->buf))
438                                 continue;
439                         if (option_local > 0)
440                                 die_errno(_("failed to create link '%s'"), dest->buf);
441                         option_no_hardlinks = 1;
442                 }
443                 if (copy_file_with_time(dest->buf, src->buf, 0666))
444                         die_errno(_("failed to copy file to '%s'"), dest->buf);
445         }
446         closedir(dir);
447 }
448
449 static void clone_local(const char *src_repo, const char *dest_repo)
450 {
451         if (option_shared) {
452                 struct strbuf alt = STRBUF_INIT;
453                 strbuf_addf(&alt, "%s/objects", src_repo);
454                 add_to_alternates_file(alt.buf);
455                 strbuf_release(&alt);
456         } else {
457                 struct strbuf src = STRBUF_INIT;
458                 struct strbuf dest = STRBUF_INIT;
459                 get_common_dir(&src, src_repo);
460                 get_common_dir(&dest, dest_repo);
461                 strbuf_addstr(&src, "/objects");
462                 strbuf_addstr(&dest, "/objects");
463                 copy_or_link_directory(&src, &dest, src_repo, src.len);
464                 strbuf_release(&src);
465                 strbuf_release(&dest);
466         }
467
468         if (0 <= option_verbosity)
469                 fprintf(stderr, _("done.\n"));
470 }
471
472 static const char *junk_work_tree;
473 static const char *junk_git_dir;
474 static enum {
475         JUNK_LEAVE_NONE,
476         JUNK_LEAVE_REPO,
477         JUNK_LEAVE_ALL
478 } junk_mode = JUNK_LEAVE_NONE;
479
480 static const char junk_leave_repo_msg[] =
481 N_("Clone succeeded, but checkout failed.\n"
482    "You can inspect what was checked out with 'git status'\n"
483    "and retry the checkout with 'git checkout -f HEAD'\n");
484
485 static void remove_junk(void)
486 {
487         struct strbuf sb = STRBUF_INIT;
488
489         switch (junk_mode) {
490         case JUNK_LEAVE_REPO:
491                 warning("%s", _(junk_leave_repo_msg));
492                 /* fall-through */
493         case JUNK_LEAVE_ALL:
494                 return;
495         default:
496                 /* proceed to removal */
497                 break;
498         }
499
500         if (junk_git_dir) {
501                 strbuf_addstr(&sb, junk_git_dir);
502                 remove_dir_recursively(&sb, 0);
503                 strbuf_reset(&sb);
504         }
505         if (junk_work_tree) {
506                 strbuf_addstr(&sb, junk_work_tree);
507                 remove_dir_recursively(&sb, 0);
508                 strbuf_reset(&sb);
509         }
510 }
511
512 static void remove_junk_on_signal(int signo)
513 {
514         remove_junk();
515         sigchain_pop(signo);
516         raise(signo);
517 }
518
519 static struct ref *find_remote_branch(const struct ref *refs, const char *branch)
520 {
521         struct ref *ref;
522         struct strbuf head = STRBUF_INIT;
523         strbuf_addstr(&head, "refs/heads/");
524         strbuf_addstr(&head, branch);
525         ref = find_ref_by_name(refs, head.buf);
526         strbuf_release(&head);
527
528         if (ref)
529                 return ref;
530
531         strbuf_addstr(&head, "refs/tags/");
532         strbuf_addstr(&head, branch);
533         ref = find_ref_by_name(refs, head.buf);
534         strbuf_release(&head);
535
536         return ref;
537 }
538
539 static struct ref *wanted_peer_refs(const struct ref *refs,
540                 struct refspec *refspec)
541 {
542         struct ref *head = copy_ref(find_ref_by_name(refs, "HEAD"));
543         struct ref *local_refs = head;
544         struct ref **tail = head ? &head->next : &local_refs;
545
546         if (option_single_branch) {
547                 struct ref *remote_head = NULL;
548
549                 if (!option_branch)
550                         remote_head = guess_remote_head(head, refs, 0);
551                 else {
552                         local_refs = NULL;
553                         tail = &local_refs;
554                         remote_head = copy_ref(find_remote_branch(refs, option_branch));
555                 }
556
557                 if (!remote_head && option_branch)
558                         warning(_("Could not find remote branch %s to clone."),
559                                 option_branch);
560                 else {
561                         get_fetch_map(remote_head, refspec, &tail, 0);
562
563                         /* if --branch=tag, pull the requested tag explicitly */
564                         get_fetch_map(remote_head, tag_refspec, &tail, 0);
565                 }
566         } else
567                 get_fetch_map(refs, refspec, &tail, 0);
568
569         if (!option_mirror && !option_single_branch && !option_no_tags)
570                 get_fetch_map(refs, tag_refspec, &tail, 0);
571
572         return local_refs;
573 }
574
575 static void write_remote_refs(const struct ref *local_refs)
576 {
577         const struct ref *r;
578
579         struct ref_transaction *t;
580         struct strbuf err = STRBUF_INIT;
581
582         t = ref_transaction_begin(&err);
583         if (!t)
584                 die("%s", err.buf);
585
586         for (r = local_refs; r; r = r->next) {
587                 if (!r->peer_ref)
588                         continue;
589                 if (ref_transaction_create(t, r->peer_ref->name, r->old_oid.hash,
590                                            0, NULL, &err))
591                         die("%s", err.buf);
592         }
593
594         if (initial_ref_transaction_commit(t, &err))
595                 die("%s", err.buf);
596
597         strbuf_release(&err);
598         ref_transaction_free(t);
599 }
600
601 static void write_followtags(const struct ref *refs, const char *msg)
602 {
603         const struct ref *ref;
604         for (ref = refs; ref; ref = ref->next) {
605                 if (!starts_with(ref->name, "refs/tags/"))
606                         continue;
607                 if (ends_with(ref->name, "^{}"))
608                         continue;
609                 if (!has_object_file(&ref->old_oid))
610                         continue;
611                 update_ref(msg, ref->name, ref->old_oid.hash,
612                            NULL, 0, UPDATE_REFS_DIE_ON_ERR);
613         }
614 }
615
616 static int iterate_ref_map(void *cb_data, unsigned char sha1[20])
617 {
618         struct ref **rm = cb_data;
619         struct ref *ref = *rm;
620
621         /*
622          * Skip anything missing a peer_ref, which we are not
623          * actually going to write a ref for.
624          */
625         while (ref && !ref->peer_ref)
626                 ref = ref->next;
627         /* Returning -1 notes "end of list" to the caller. */
628         if (!ref)
629                 return -1;
630
631         hashcpy(sha1, ref->old_oid.hash);
632         *rm = ref->next;
633         return 0;
634 }
635
636 static void update_remote_refs(const struct ref *refs,
637                                const struct ref *mapped_refs,
638                                const struct ref *remote_head_points_at,
639                                const char *branch_top,
640                                const char *msg,
641                                struct transport *transport,
642                                int check_connectivity)
643 {
644         const struct ref *rm = mapped_refs;
645
646         if (check_connectivity) {
647                 struct check_connected_options opt = CHECK_CONNECTED_INIT;
648
649                 opt.transport = transport;
650                 opt.progress = transport->progress;
651
652                 if (check_connected(iterate_ref_map, &rm, &opt))
653                         die(_("remote did not send all necessary objects"));
654         }
655
656         if (refs) {
657                 write_remote_refs(mapped_refs);
658                 if (option_single_branch && !option_no_tags)
659                         write_followtags(refs, msg);
660         }
661
662         if (remote_head_points_at && !option_bare) {
663                 struct strbuf head_ref = STRBUF_INIT;
664                 strbuf_addstr(&head_ref, branch_top);
665                 strbuf_addstr(&head_ref, "HEAD");
666                 if (create_symref(head_ref.buf,
667                                   remote_head_points_at->peer_ref->name,
668                                   msg) < 0)
669                         die(_("unable to update %s"), head_ref.buf);
670                 strbuf_release(&head_ref);
671         }
672 }
673
674 static void update_head(const struct ref *our, const struct ref *remote,
675                         const char *msg)
676 {
677         const char *head;
678         if (our && skip_prefix(our->name, "refs/heads/", &head)) {
679                 /* Local default branch link */
680                 if (create_symref("HEAD", our->name, NULL) < 0)
681                         die(_("unable to update HEAD"));
682                 if (!option_bare) {
683                         update_ref(msg, "HEAD", our->old_oid.hash, NULL, 0,
684                                    UPDATE_REFS_DIE_ON_ERR);
685                         install_branch_config(0, head, option_origin, our->name);
686                 }
687         } else if (our) {
688                 struct commit *c = lookup_commit_reference(&our->old_oid);
689                 /* --branch specifies a non-branch (i.e. tags), detach HEAD */
690                 update_ref(msg, "HEAD", c->object.oid.hash,
691                            NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
692         } else if (remote) {
693                 /*
694                  * We know remote HEAD points to a non-branch, or
695                  * HEAD points to a branch but we don't know which one.
696                  * Detach HEAD in all these cases.
697                  */
698                 update_ref(msg, "HEAD", remote->old_oid.hash,
699                            NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
700         }
701 }
702
703 static int checkout(int submodule_progress)
704 {
705         struct object_id oid;
706         char *head;
707         struct lock_file *lock_file;
708         struct unpack_trees_options opts;
709         struct tree *tree;
710         struct tree_desc t;
711         int err = 0;
712
713         if (option_no_checkout)
714                 return 0;
715
716         head = resolve_refdup("HEAD", RESOLVE_REF_READING, oid.hash, NULL);
717         if (!head) {
718                 warning(_("remote HEAD refers to nonexistent ref, "
719                           "unable to checkout.\n"));
720                 return 0;
721         }
722         if (!strcmp(head, "HEAD")) {
723                 if (advice_detached_head)
724                         detach_advice(oid_to_hex(&oid));
725         } else {
726                 if (!starts_with(head, "refs/heads/"))
727                         die(_("HEAD not found below refs/heads!"));
728         }
729         free(head);
730
731         /* We need to be in the new work tree for the checkout */
732         setup_work_tree();
733
734         lock_file = xcalloc(1, sizeof(struct lock_file));
735         hold_locked_index(lock_file, LOCK_DIE_ON_ERROR);
736
737         memset(&opts, 0, sizeof opts);
738         opts.update = 1;
739         opts.merge = 1;
740         opts.fn = oneway_merge;
741         opts.verbose_update = (option_verbosity >= 0);
742         opts.src_index = &the_index;
743         opts.dst_index = &the_index;
744
745         tree = parse_tree_indirect(&oid);
746         parse_tree(tree);
747         init_tree_desc(&t, tree->buffer, tree->size);
748         if (unpack_trees(1, &t, &opts) < 0)
749                 die(_("unable to checkout working tree"));
750
751         if (write_locked_index(&the_index, lock_file, COMMIT_LOCK))
752                 die(_("unable to write new index file"));
753
754         err |= run_hook_le(NULL, "post-checkout", sha1_to_hex(null_sha1),
755                            oid_to_hex(&oid), "1", NULL);
756
757         if (!err && (option_recurse_submodules.nr > 0)) {
758                 struct argv_array args = ARGV_ARRAY_INIT;
759                 argv_array_pushl(&args, "submodule", "update", "--init", "--recursive", NULL);
760
761                 if (option_shallow_submodules == 1)
762                         argv_array_push(&args, "--depth=1");
763
764                 if (max_jobs != -1)
765                         argv_array_pushf(&args, "--jobs=%d", max_jobs);
766
767                 if (submodule_progress)
768                         argv_array_push(&args, "--progress");
769
770                 err = run_command_v_opt(args.argv, RUN_GIT_CMD);
771                 argv_array_clear(&args);
772         }
773
774         return err;
775 }
776
777 static int write_one_config(const char *key, const char *value, void *data)
778 {
779         return git_config_set_multivar_gently(key,
780                                               value ? value : "true",
781                                               CONFIG_REGEX_NONE, 0);
782 }
783
784 static void write_config(struct string_list *config)
785 {
786         int i;
787
788         for (i = 0; i < config->nr; i++) {
789                 if (git_config_parse_parameter(config->items[i].string,
790                                                write_one_config, NULL) < 0)
791                         die(_("unable to write parameters to config file"));
792         }
793 }
794
795 static void write_refspec_config(const char *src_ref_prefix,
796                 const struct ref *our_head_points_at,
797                 const struct ref *remote_head_points_at,
798                 struct strbuf *branch_top)
799 {
800         struct strbuf key = STRBUF_INIT;
801         struct strbuf value = STRBUF_INIT;
802
803         if (option_mirror || !option_bare) {
804                 if (option_single_branch && !option_mirror) {
805                         if (option_branch) {
806                                 if (starts_with(our_head_points_at->name, "refs/tags/"))
807                                         strbuf_addf(&value, "+%s:%s", our_head_points_at->name,
808                                                 our_head_points_at->name);
809                                 else
810                                         strbuf_addf(&value, "+%s:%s%s", our_head_points_at->name,
811                                                 branch_top->buf, option_branch);
812                         } else if (remote_head_points_at) {
813                                 const char *head = remote_head_points_at->name;
814                                 if (!skip_prefix(head, "refs/heads/", &head))
815                                         die("BUG: remote HEAD points at non-head?");
816
817                                 strbuf_addf(&value, "+%s:%s%s", remote_head_points_at->name,
818                                                 branch_top->buf, head);
819                         }
820                         /*
821                          * otherwise, the next "git fetch" will
822                          * simply fetch from HEAD without updating
823                          * any remote-tracking branch, which is what
824                          * we want.
825                          */
826                 } else {
827                         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top->buf);
828                 }
829                 /* Configure the remote */
830                 if (value.len) {
831                         strbuf_addf(&key, "remote.%s.fetch", option_origin);
832                         git_config_set_multivar(key.buf, value.buf, "^$", 0);
833                         strbuf_reset(&key);
834
835                         if (option_mirror) {
836                                 strbuf_addf(&key, "remote.%s.mirror", option_origin);
837                                 git_config_set(key.buf, "true");
838                                 strbuf_reset(&key);
839                         }
840                 }
841         }
842
843         strbuf_release(&key);
844         strbuf_release(&value);
845 }
846
847 static void dissociate_from_references(void)
848 {
849         static const char* argv[] = { "repack", "-a", "-d", NULL };
850         char *alternates = git_pathdup("objects/info/alternates");
851
852         if (!access(alternates, F_OK)) {
853                 if (run_command_v_opt(argv, RUN_GIT_CMD|RUN_COMMAND_NO_STDIN))
854                         die(_("cannot repack to clean up"));
855                 if (unlink(alternates) && errno != ENOENT)
856                         die_errno(_("cannot unlink temporary alternates file"));
857         }
858         free(alternates);
859 }
860
861 int cmd_clone(int argc, const char **argv, const char *prefix)
862 {
863         int is_bundle = 0, is_local;
864         struct stat buf;
865         const char *repo_name, *repo, *work_tree, *git_dir;
866         char *path, *dir;
867         int dest_exists;
868         const struct ref *refs, *remote_head;
869         const struct ref *remote_head_points_at;
870         const struct ref *our_head_points_at;
871         struct ref *mapped_refs;
872         const struct ref *ref;
873         struct strbuf key = STRBUF_INIT, value = STRBUF_INIT;
874         struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
875         struct transport *transport = NULL;
876         const char *src_ref_prefix = "refs/heads/";
877         struct remote *remote;
878         int err = 0, complete_refs_before_fetch = 1;
879         int submodule_progress;
880
881         struct refspec *refspec;
882         const char *fetch_pattern;
883
884         packet_trace_identity("clone");
885         argc = parse_options(argc, argv, prefix, builtin_clone_options,
886                              builtin_clone_usage, 0);
887
888         if (argc > 2)
889                 usage_msg_opt(_("Too many arguments."),
890                         builtin_clone_usage, builtin_clone_options);
891
892         if (argc == 0)
893                 usage_msg_opt(_("You must specify a repository to clone."),
894                         builtin_clone_usage, builtin_clone_options);
895
896         if (option_depth || option_since || option_not.nr)
897                 deepen = 1;
898         if (option_single_branch == -1)
899                 option_single_branch = deepen ? 1 : 0;
900
901         if (option_mirror)
902                 option_bare = 1;
903
904         if (option_bare) {
905                 if (option_origin)
906                         die(_("--bare and --origin %s options are incompatible."),
907                             option_origin);
908                 if (real_git_dir)
909                         die(_("--bare and --separate-git-dir are incompatible."));
910                 option_no_checkout = 1;
911         }
912
913         if (!option_origin)
914                 option_origin = "origin";
915
916         repo_name = argv[0];
917
918         path = get_repo_path(repo_name, &is_bundle);
919         if (path)
920                 repo = absolute_pathdup(repo_name);
921         else if (!strchr(repo_name, ':'))
922                 die(_("repository '%s' does not exist"), repo_name);
923         else
924                 repo = repo_name;
925
926         /* no need to be strict, transport_set_option() will validate it again */
927         if (option_depth && atoi(option_depth) < 1)
928                 die(_("depth %s is not a positive number"), option_depth);
929
930         if (argc == 2)
931                 dir = xstrdup(argv[1]);
932         else
933                 dir = guess_dir_name(repo_name, is_bundle, option_bare);
934         strip_trailing_slashes(dir);
935
936         dest_exists = !stat(dir, &buf);
937         if (dest_exists && !is_empty_dir(dir))
938                 die(_("destination path '%s' already exists and is not "
939                         "an empty directory."), dir);
940
941         strbuf_addf(&reflog_msg, "clone: from %s", repo);
942
943         if (option_bare)
944                 work_tree = NULL;
945         else {
946                 work_tree = getenv("GIT_WORK_TREE");
947                 if (work_tree && !stat(work_tree, &buf))
948                         die(_("working tree '%s' already exists."), work_tree);
949         }
950
951         if (option_bare || work_tree)
952                 git_dir = xstrdup(dir);
953         else {
954                 work_tree = dir;
955                 git_dir = mkpathdup("%s/.git", dir);
956         }
957
958         atexit(remove_junk);
959         sigchain_push_common(remove_junk_on_signal);
960
961         if (!option_bare) {
962                 if (safe_create_leading_directories_const(work_tree) < 0)
963                         die_errno(_("could not create leading directories of '%s'"),
964                                   work_tree);
965                 if (!dest_exists && mkdir(work_tree, 0777))
966                         die_errno(_("could not create work tree dir '%s'"),
967                                   work_tree);
968                 junk_work_tree = work_tree;
969                 set_git_work_tree(work_tree);
970         }
971
972         junk_git_dir = real_git_dir ? real_git_dir : git_dir;
973         if (safe_create_leading_directories_const(git_dir) < 0)
974                 die(_("could not create leading directories of '%s'"), git_dir);
975
976         if (0 <= option_verbosity) {
977                 if (option_bare)
978                         fprintf(stderr, _("Cloning into bare repository '%s'...\n"), dir);
979                 else
980                         fprintf(stderr, _("Cloning into '%s'...\n"), dir);
981         }
982
983         if (option_recurse_submodules.nr > 0) {
984                 struct string_list_item *item;
985                 struct strbuf sb = STRBUF_INIT;
986
987                 /* remove duplicates */
988                 string_list_sort(&option_recurse_submodules);
989                 string_list_remove_duplicates(&option_recurse_submodules, 0);
990
991                 /*
992                  * NEEDSWORK: In a multi-working-tree world, this needs to be
993                  * set in the per-worktree config.
994                  */
995                 for_each_string_list_item(item, &option_recurse_submodules) {
996                         strbuf_addf(&sb, "submodule.active=%s",
997                                     item->string);
998                         string_list_append(&option_config,
999                                            strbuf_detach(&sb, NULL));
1000                 }
1001
1002                 if (option_required_reference.nr &&
1003                     option_optional_reference.nr)
1004                         die(_("clone --recursive is not compatible with "
1005                               "both --reference and --reference-if-able"));
1006                 else if (option_required_reference.nr) {
1007                         string_list_append(&option_config,
1008                                 "submodule.alternateLocation=superproject");
1009                         string_list_append(&option_config,
1010                                 "submodule.alternateErrorStrategy=die");
1011                 } else if (option_optional_reference.nr) {
1012                         string_list_append(&option_config,
1013                                 "submodule.alternateLocation=superproject");
1014                         string_list_append(&option_config,
1015                                 "submodule.alternateErrorStrategy=info");
1016                 }
1017         }
1018
1019         init_db(git_dir, real_git_dir, option_template, INIT_DB_QUIET);
1020
1021         if (real_git_dir)
1022                 git_dir = real_git_dir;
1023
1024         write_config(&option_config);
1025
1026         git_config(git_default_config, NULL);
1027
1028         if (option_bare) {
1029                 if (option_mirror)
1030                         src_ref_prefix = "refs/";
1031                 strbuf_addstr(&branch_top, src_ref_prefix);
1032
1033                 git_config_set("core.bare", "true");
1034         } else {
1035                 strbuf_addf(&branch_top, "refs/remotes/%s/", option_origin);
1036         }
1037
1038         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top.buf);
1039         strbuf_addf(&key, "remote.%s.url", option_origin);
1040         git_config_set(key.buf, repo);
1041         strbuf_reset(&key);
1042
1043         if (option_no_tags) {
1044                 strbuf_addf(&key, "remote.%s.tagOpt", option_origin);
1045                 git_config_set(key.buf, "--no-tags");
1046                 strbuf_reset(&key);
1047         }
1048
1049         if (option_required_reference.nr || option_optional_reference.nr)
1050                 setup_reference();
1051
1052         fetch_pattern = value.buf;
1053         refspec = parse_fetch_refspec(1, &fetch_pattern);
1054
1055         strbuf_reset(&value);
1056
1057         remote = remote_get(option_origin);
1058         transport = transport_get(remote, remote->url[0]);
1059         transport_set_verbosity(transport, option_verbosity, option_progress);
1060         transport->family = family;
1061
1062         path = get_repo_path(remote->url[0], &is_bundle);
1063         is_local = option_local != 0 && path && !is_bundle;
1064         if (is_local) {
1065                 if (option_depth)
1066                         warning(_("--depth is ignored in local clones; use file:// instead."));
1067                 if (option_since)
1068                         warning(_("--shallow-since is ignored in local clones; use file:// instead."));
1069                 if (option_not.nr)
1070                         warning(_("--shallow-exclude is ignored in local clones; use file:// instead."));
1071                 if (!access(mkpath("%s/shallow", path), F_OK)) {
1072                         if (option_local > 0)
1073                                 warning(_("source repository is shallow, ignoring --local"));
1074                         is_local = 0;
1075                 }
1076         }
1077         if (option_local > 0 && !is_local)
1078                 warning(_("--local is ignored"));
1079         transport->cloning = 1;
1080
1081         if (!transport->get_refs_list || (!is_local && !transport->fetch))
1082                 die(_("Don't know how to clone %s"), transport->url);
1083
1084         transport_set_option(transport, TRANS_OPT_KEEP, "yes");
1085
1086         if (option_depth)
1087                 transport_set_option(transport, TRANS_OPT_DEPTH,
1088                                      option_depth);
1089         if (option_since)
1090                 transport_set_option(transport, TRANS_OPT_DEEPEN_SINCE,
1091                                      option_since);
1092         if (option_not.nr)
1093                 transport_set_option(transport, TRANS_OPT_DEEPEN_NOT,
1094                                      (const char *)&option_not);
1095         if (option_single_branch)
1096                 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
1097
1098         if (option_upload_pack)
1099                 transport_set_option(transport, TRANS_OPT_UPLOADPACK,
1100                                      option_upload_pack);
1101
1102         if (transport->smart_options && !deepen)
1103                 transport->smart_options->check_self_contained_and_connected = 1;
1104
1105         refs = transport_get_remote_refs(transport);
1106
1107         if (refs) {
1108                 mapped_refs = wanted_peer_refs(refs, refspec);
1109                 /*
1110                  * transport_get_remote_refs() may return refs with null sha-1
1111                  * in mapped_refs (see struct transport->get_refs_list
1112                  * comment). In that case we need fetch it early because
1113                  * remote_head code below relies on it.
1114                  *
1115                  * for normal clones, transport_get_remote_refs() should
1116                  * return reliable ref set, we can delay cloning until after
1117                  * remote HEAD check.
1118                  */
1119                 for (ref = refs; ref; ref = ref->next)
1120                         if (is_null_oid(&ref->old_oid)) {
1121                                 complete_refs_before_fetch = 0;
1122                                 break;
1123                         }
1124
1125                 if (!is_local && !complete_refs_before_fetch)
1126                         transport_fetch_refs(transport, mapped_refs);
1127
1128                 remote_head = find_ref_by_name(refs, "HEAD");
1129                 remote_head_points_at =
1130                         guess_remote_head(remote_head, mapped_refs, 0);
1131
1132                 if (option_branch) {
1133                         our_head_points_at =
1134                                 find_remote_branch(mapped_refs, option_branch);
1135
1136                         if (!our_head_points_at)
1137                                 die(_("Remote branch %s not found in upstream %s"),
1138                                     option_branch, option_origin);
1139                 }
1140                 else
1141                         our_head_points_at = remote_head_points_at;
1142         }
1143         else {
1144                 if (option_branch)
1145                         die(_("Remote branch %s not found in upstream %s"),
1146                                         option_branch, option_origin);
1147
1148                 warning(_("You appear to have cloned an empty repository."));
1149                 mapped_refs = NULL;
1150                 our_head_points_at = NULL;
1151                 remote_head_points_at = NULL;
1152                 remote_head = NULL;
1153                 option_no_checkout = 1;
1154                 if (!option_bare)
1155                         install_branch_config(0, "master", option_origin,
1156                                               "refs/heads/master");
1157         }
1158
1159         write_refspec_config(src_ref_prefix, our_head_points_at,
1160                         remote_head_points_at, &branch_top);
1161
1162         if (is_local)
1163                 clone_local(path, git_dir);
1164         else if (refs && complete_refs_before_fetch)
1165                 transport_fetch_refs(transport, mapped_refs);
1166
1167         update_remote_refs(refs, mapped_refs, remote_head_points_at,
1168                            branch_top.buf, reflog_msg.buf, transport, !is_local);
1169
1170         update_head(our_head_points_at, remote_head, reflog_msg.buf);
1171
1172         /*
1173          * We want to show progress for recursive submodule clones iff
1174          * we did so for the main clone. But only the transport knows
1175          * the final decision for this flag, so we need to rescue the value
1176          * before we free the transport.
1177          */
1178         submodule_progress = transport->progress;
1179
1180         transport_unlock_pack(transport);
1181         transport_disconnect(transport);
1182
1183         if (option_dissociate) {
1184                 close_all_packs();
1185                 dissociate_from_references();
1186         }
1187
1188         junk_mode = JUNK_LEAVE_REPO;
1189         err = checkout(submodule_progress);
1190
1191         strbuf_release(&reflog_msg);
1192         strbuf_release(&branch_top);
1193         strbuf_release(&key);
1194         strbuf_release(&value);
1195         junk_mode = JUNK_LEAVE_ALL;
1196
1197         free(refspec);
1198         return err;
1199 }