Merge branch 'jk/options-cleanup'
[git] / transport.c
1 #include "cache.h"
2 #include "transport.h"
3 #include "run-command.h"
4 #include "pkt-line.h"
5 #include "fetch-pack.h"
6 #include "remote.h"
7 #include "connect.h"
8 #include "send-pack.h"
9 #include "walker.h"
10 #include "bundle.h"
11 #include "dir.h"
12 #include "refs.h"
13 #include "branch.h"
14 #include "url.h"
15 #include "submodule.h"
16 #include "string-list.h"
17 #include "sha1-array.h"
18 #include "sigchain.h"
19
20 /* rsync support */
21
22 /*
23  * We copy packed-refs and refs/ into a temporary file, then read the
24  * loose refs recursively (sorting whenever possible), and then inserting
25  * those packed refs that are not yet in the list (not validating, but
26  * assuming that the file is sorted).
27  *
28  * Appears refactoring this from refs.c is too cumbersome.
29  */
30
31 static int str_cmp(const void *a, const void *b)
32 {
33         const char *s1 = a;
34         const char *s2 = b;
35
36         return strcmp(s1, s2);
37 }
38
39 /* path->buf + name_offset is expected to point to "refs/" */
40
41 static int read_loose_refs(struct strbuf *path, int name_offset,
42                 struct ref **tail)
43 {
44         DIR *dir = opendir(path->buf);
45         struct dirent *de;
46         struct {
47                 char **entries;
48                 int nr, alloc;
49         } list;
50         int i, pathlen;
51
52         if (!dir)
53                 return -1;
54
55         memset (&list, 0, sizeof(list));
56
57         while ((de = readdir(dir))) {
58                 if (is_dot_or_dotdot(de->d_name))
59                         continue;
60                 ALLOC_GROW(list.entries, list.nr + 1, list.alloc);
61                 list.entries[list.nr++] = xstrdup(de->d_name);
62         }
63         closedir(dir);
64
65         /* sort the list */
66
67         qsort(list.entries, list.nr, sizeof(char *), str_cmp);
68
69         pathlen = path->len;
70         strbuf_addch(path, '/');
71
72         for (i = 0; i < list.nr; i++, strbuf_setlen(path, pathlen + 1)) {
73                 strbuf_addstr(path, list.entries[i]);
74                 if (read_loose_refs(path, name_offset, tail)) {
75                         int fd = open(path->buf, O_RDONLY);
76                         char buffer[40];
77                         struct ref *next;
78
79                         if (fd < 0)
80                                 continue;
81                         next = alloc_ref(path->buf + name_offset);
82                         if (read_in_full(fd, buffer, 40) != 40 ||
83                                         get_oid_hex(buffer, &next->old_oid)) {
84                                 close(fd);
85                                 free(next);
86                                 continue;
87                         }
88                         close(fd);
89                         (*tail)->next = next;
90                         *tail = next;
91                 }
92         }
93         strbuf_setlen(path, pathlen);
94
95         for (i = 0; i < list.nr; i++)
96                 free(list.entries[i]);
97         free(list.entries);
98
99         return 0;
100 }
101
102 /* insert the packed refs for which no loose refs were found */
103
104 static void insert_packed_refs(const char *packed_refs, struct ref **list)
105 {
106         FILE *f = fopen(packed_refs, "r");
107         static char buffer[PATH_MAX];
108
109         if (!f)
110                 return;
111
112         for (;;) {
113                 int cmp = 0; /* assigned before used */
114                 int len;
115
116                 if (!fgets(buffer, sizeof(buffer), f)) {
117                         fclose(f);
118                         return;
119                 }
120
121                 if (!isxdigit(buffer[0]))
122                         continue;
123                 len = strlen(buffer);
124                 if (len && buffer[len - 1] == '\n')
125                         buffer[--len] = '\0';
126                 if (len < 41)
127                         continue;
128                 while ((*list)->next &&
129                                 (cmp = strcmp(buffer + 41,
130                                       (*list)->next->name)) > 0)
131                         list = &(*list)->next;
132                 if (!(*list)->next || cmp < 0) {
133                         struct ref *next = alloc_ref(buffer + 41);
134                         buffer[40] = '\0';
135                         if (get_oid_hex(buffer, &next->old_oid)) {
136                                 warning ("invalid SHA-1: %s", buffer);
137                                 free(next);
138                                 continue;
139                         }
140                         next->next = (*list)->next;
141                         (*list)->next = next;
142                         list = &(*list)->next;
143                 }
144         }
145 }
146
147 static void set_upstreams(struct transport *transport, struct ref *refs,
148         int pretend)
149 {
150         struct ref *ref;
151         for (ref = refs; ref; ref = ref->next) {
152                 const char *localname;
153                 const char *tmp;
154                 const char *remotename;
155                 unsigned char sha[20];
156                 int flag = 0;
157                 /*
158                  * Check suitability for tracking. Must be successful /
159                  * already up-to-date ref create/modify (not delete).
160                  */
161                 if (ref->status != REF_STATUS_OK &&
162                         ref->status != REF_STATUS_UPTODATE)
163                         continue;
164                 if (!ref->peer_ref)
165                         continue;
166                 if (is_null_oid(&ref->new_oid))
167                         continue;
168
169                 /* Follow symbolic refs (mainly for HEAD). */
170                 localname = ref->peer_ref->name;
171                 remotename = ref->name;
172                 tmp = resolve_ref_unsafe(localname, RESOLVE_REF_READING,
173                                          sha, &flag);
174                 if (tmp && flag & REF_ISSYMREF &&
175                         starts_with(tmp, "refs/heads/"))
176                         localname = tmp;
177
178                 /* Both source and destination must be local branches. */
179                 if (!localname || !starts_with(localname, "refs/heads/"))
180                         continue;
181                 if (!remotename || !starts_with(remotename, "refs/heads/"))
182                         continue;
183
184                 if (!pretend)
185                         install_branch_config(BRANCH_CONFIG_VERBOSE,
186                                 localname + 11, transport->remote->name,
187                                 remotename);
188                 else
189                         printf("Would set upstream of '%s' to '%s' of '%s'\n",
190                                 localname + 11, remotename + 11,
191                                 transport->remote->name);
192         }
193 }
194
195 static const char *rsync_url(const char *url)
196 {
197         if (!starts_with(url, "rsync://"))
198                 skip_prefix(url, "rsync:", &url);
199         return url;
200 }
201
202 static struct ref *get_refs_via_rsync(struct transport *transport, int for_push)
203 {
204         struct strbuf buf = STRBUF_INIT, temp_dir = STRBUF_INIT;
205         struct ref dummy = {NULL}, *tail = &dummy;
206         struct child_process rsync = CHILD_PROCESS_INIT;
207         const char *args[5];
208         int temp_dir_len;
209
210         if (for_push)
211                 return NULL;
212
213         /* copy the refs to the temporary directory */
214
215         strbuf_addstr(&temp_dir, git_path("rsync-refs-XXXXXX"));
216         if (!mkdtemp(temp_dir.buf))
217                 die_errno ("Could not make temporary directory");
218         temp_dir_len = temp_dir.len;
219
220         strbuf_addstr(&buf, rsync_url(transport->url));
221         strbuf_addstr(&buf, "/refs");
222
223         rsync.argv = args;
224         rsync.stdout_to_stderr = 1;
225         args[0] = "rsync";
226         args[1] = (transport->verbose > 1) ? "-rv" : "-r";
227         args[2] = buf.buf;
228         args[3] = temp_dir.buf;
229         args[4] = NULL;
230
231         if (run_command(&rsync))
232                 die ("Could not run rsync to get refs");
233
234         strbuf_reset(&buf);
235         strbuf_addstr(&buf, rsync_url(transport->url));
236         strbuf_addstr(&buf, "/packed-refs");
237
238         args[2] = buf.buf;
239
240         if (run_command(&rsync))
241                 die ("Could not run rsync to get refs");
242
243         /* read the copied refs */
244
245         strbuf_addstr(&temp_dir, "/refs");
246         read_loose_refs(&temp_dir, temp_dir_len + 1, &tail);
247         strbuf_setlen(&temp_dir, temp_dir_len);
248
249         tail = &dummy;
250         strbuf_addstr(&temp_dir, "/packed-refs");
251         insert_packed_refs(temp_dir.buf, &tail);
252         strbuf_setlen(&temp_dir, temp_dir_len);
253
254         if (remove_dir_recursively(&temp_dir, 0))
255                 warning ("Error removing temporary directory %s.",
256                                 temp_dir.buf);
257
258         strbuf_release(&buf);
259         strbuf_release(&temp_dir);
260
261         return dummy.next;
262 }
263
264 static int fetch_objs_via_rsync(struct transport *transport,
265                                 int nr_objs, struct ref **to_fetch)
266 {
267         struct child_process rsync = CHILD_PROCESS_INIT;
268
269         rsync.stdout_to_stderr = 1;
270         argv_array_push(&rsync.args, "rsync");
271         argv_array_push(&rsync.args, (transport->verbose > 1) ? "-rv" : "-r");
272         argv_array_push(&rsync.args, "--ignore-existing");
273         argv_array_push(&rsync.args, "--exclude");
274         argv_array_push(&rsync.args, "info");
275         argv_array_pushf(&rsync.args, "%s/objects/", rsync_url(transport->url));
276         argv_array_push(&rsync.args, get_object_directory());
277
278         /* NEEDSWORK: handle one level of alternates */
279         return run_command(&rsync);
280 }
281
282 static int write_one_ref(const char *name, const struct object_id *oid,
283                          int flags, void *data)
284 {
285         struct strbuf *buf = data;
286         int len = buf->len;
287
288         /* when called via for_each_ref(), flags is non-zero */
289         if (flags && !starts_with(name, "refs/heads/") &&
290                         !starts_with(name, "refs/tags/"))
291                 return 0;
292
293         strbuf_addstr(buf, name);
294         if (safe_create_leading_directories(buf->buf) ||
295             write_file_gently(buf->buf, "%s", oid_to_hex(oid)))
296                 return error("problems writing temporary file %s: %s",
297                              buf->buf, strerror(errno));
298         strbuf_setlen(buf, len);
299         return 0;
300 }
301
302 static int write_refs_to_temp_dir(struct strbuf *temp_dir,
303                                   int refspec_nr, const char **refspec)
304 {
305         int i;
306
307         for (i = 0; i < refspec_nr; i++) {
308                 struct object_id oid;
309                 char *ref;
310
311                 if (dwim_ref(refspec[i], strlen(refspec[i]), oid.hash, &ref) != 1)
312                         return error("Could not get ref %s", refspec[i]);
313
314                 if (write_one_ref(ref, &oid, 0, temp_dir)) {
315                         free(ref);
316                         return -1;
317                 }
318                 free(ref);
319         }
320         return 0;
321 }
322
323 static int rsync_transport_push(struct transport *transport,
324                 int refspec_nr, const char **refspec, int flags)
325 {
326         struct strbuf buf = STRBUF_INIT, temp_dir = STRBUF_INIT;
327         int result = 0, i;
328         struct child_process rsync = CHILD_PROCESS_INIT;
329         const char *args[10];
330
331         if (flags & TRANSPORT_PUSH_MIRROR)
332                 return error("rsync transport does not support mirror mode");
333
334         /* first push the objects */
335
336         strbuf_addstr(&buf, rsync_url(transport->url));
337         strbuf_addch(&buf, '/');
338
339         rsync.argv = args;
340         rsync.stdout_to_stderr = 1;
341         i = 0;
342         args[i++] = "rsync";
343         args[i++] = "-a";
344         if (flags & TRANSPORT_PUSH_DRY_RUN)
345                 args[i++] = "--dry-run";
346         if (transport->verbose > 1)
347                 args[i++] = "-v";
348         args[i++] = "--ignore-existing";
349         args[i++] = "--exclude";
350         args[i++] = "info";
351         args[i++] = get_object_directory();
352         args[i++] = buf.buf;
353         args[i++] = NULL;
354
355         if (run_command(&rsync))
356                 return error("Could not push objects to %s",
357                                 rsync_url(transport->url));
358
359         /* copy the refs to the temporary directory; they could be packed. */
360
361         strbuf_addstr(&temp_dir, git_path("rsync-refs-XXXXXX"));
362         if (!mkdtemp(temp_dir.buf))
363                 die_errno ("Could not make temporary directory");
364         strbuf_addch(&temp_dir, '/');
365
366         if (flags & TRANSPORT_PUSH_ALL) {
367                 if (for_each_ref(write_one_ref, &temp_dir))
368                         return -1;
369         } else if (write_refs_to_temp_dir(&temp_dir, refspec_nr, refspec))
370                 return -1;
371
372         i = 2;
373         if (flags & TRANSPORT_PUSH_DRY_RUN)
374                 args[i++] = "--dry-run";
375         if (!(flags & TRANSPORT_PUSH_FORCE))
376                 args[i++] = "--ignore-existing";
377         args[i++] = temp_dir.buf;
378         args[i++] = rsync_url(transport->url);
379         args[i++] = NULL;
380         if (run_command(&rsync))
381                 result = error("Could not push to %s",
382                                 rsync_url(transport->url));
383
384         if (remove_dir_recursively(&temp_dir, 0))
385                 warning ("Could not remove temporary directory %s.",
386                                 temp_dir.buf);
387
388         strbuf_release(&buf);
389         strbuf_release(&temp_dir);
390
391         return result;
392 }
393
394 struct bundle_transport_data {
395         int fd;
396         struct bundle_header header;
397 };
398
399 static struct ref *get_refs_from_bundle(struct transport *transport, int for_push)
400 {
401         struct bundle_transport_data *data = transport->data;
402         struct ref *result = NULL;
403         int i;
404
405         if (for_push)
406                 return NULL;
407
408         if (data->fd > 0)
409                 close(data->fd);
410         data->fd = read_bundle_header(transport->url, &data->header);
411         if (data->fd < 0)
412                 die ("Could not read bundle '%s'.", transport->url);
413         for (i = 0; i < data->header.references.nr; i++) {
414                 struct ref_list_entry *e = data->header.references.list + i;
415                 struct ref *ref = alloc_ref(e->name);
416                 hashcpy(ref->old_oid.hash, e->sha1);
417                 ref->next = result;
418                 result = ref;
419         }
420         return result;
421 }
422
423 static int fetch_refs_from_bundle(struct transport *transport,
424                                int nr_heads, struct ref **to_fetch)
425 {
426         struct bundle_transport_data *data = transport->data;
427         return unbundle(&data->header, data->fd,
428                         transport->progress ? BUNDLE_VERBOSE : 0);
429 }
430
431 static int close_bundle(struct transport *transport)
432 {
433         struct bundle_transport_data *data = transport->data;
434         if (data->fd > 0)
435                 close(data->fd);
436         free(data);
437         return 0;
438 }
439
440 struct git_transport_data {
441         struct git_transport_options options;
442         struct child_process *conn;
443         int fd[2];
444         unsigned got_remote_heads : 1;
445         struct sha1_array extra_have;
446         struct sha1_array shallow;
447 };
448
449 static int set_git_option(struct git_transport_options *opts,
450                           const char *name, const char *value)
451 {
452         if (!strcmp(name, TRANS_OPT_UPLOADPACK)) {
453                 opts->uploadpack = value;
454                 return 0;
455         } else if (!strcmp(name, TRANS_OPT_RECEIVEPACK)) {
456                 opts->receivepack = value;
457                 return 0;
458         } else if (!strcmp(name, TRANS_OPT_THIN)) {
459                 opts->thin = !!value;
460                 return 0;
461         } else if (!strcmp(name, TRANS_OPT_FOLLOWTAGS)) {
462                 opts->followtags = !!value;
463                 return 0;
464         } else if (!strcmp(name, TRANS_OPT_KEEP)) {
465                 opts->keep = !!value;
466                 return 0;
467         } else if (!strcmp(name, TRANS_OPT_UPDATE_SHALLOW)) {
468                 opts->update_shallow = !!value;
469                 return 0;
470         } else if (!strcmp(name, TRANS_OPT_DEPTH)) {
471                 if (!value)
472                         opts->depth = 0;
473                 else {
474                         char *end;
475                         opts->depth = strtol(value, &end, 0);
476                         if (*end)
477                                 die("transport: invalid depth option '%s'", value);
478                 }
479                 return 0;
480         }
481         return 1;
482 }
483
484 static int connect_setup(struct transport *transport, int for_push)
485 {
486         struct git_transport_data *data = transport->data;
487         int flags = transport->verbose > 0 ? CONNECT_VERBOSE : 0;
488
489         if (data->conn)
490                 return 0;
491
492         data->conn = git_connect(data->fd, transport->url,
493                                  for_push ? data->options.receivepack :
494                                  data->options.uploadpack,
495                                  flags);
496
497         return 0;
498 }
499
500 static struct ref *get_refs_via_connect(struct transport *transport, int for_push)
501 {
502         struct git_transport_data *data = transport->data;
503         struct ref *refs;
504
505         connect_setup(transport, for_push);
506         get_remote_heads(data->fd[0], NULL, 0, &refs,
507                          for_push ? REF_NORMAL : 0,
508                          &data->extra_have,
509                          &data->shallow);
510         data->got_remote_heads = 1;
511
512         return refs;
513 }
514
515 static int fetch_refs_via_pack(struct transport *transport,
516                                int nr_heads, struct ref **to_fetch)
517 {
518         struct git_transport_data *data = transport->data;
519         struct ref *refs;
520         char *dest = xstrdup(transport->url);
521         struct fetch_pack_args args;
522         struct ref *refs_tmp = NULL;
523
524         memset(&args, 0, sizeof(args));
525         args.uploadpack = data->options.uploadpack;
526         args.keep_pack = data->options.keep;
527         args.lock_pack = 1;
528         args.use_thin_pack = data->options.thin;
529         args.include_tag = data->options.followtags;
530         args.verbose = (transport->verbose > 1);
531         args.quiet = (transport->verbose < 0);
532         args.no_progress = !transport->progress;
533         args.depth = data->options.depth;
534         args.check_self_contained_and_connected =
535                 data->options.check_self_contained_and_connected;
536         args.cloning = transport->cloning;
537         args.update_shallow = data->options.update_shallow;
538
539         if (!data->got_remote_heads) {
540                 connect_setup(transport, 0);
541                 get_remote_heads(data->fd[0], NULL, 0, &refs_tmp, 0,
542                                  NULL, &data->shallow);
543                 data->got_remote_heads = 1;
544         }
545
546         refs = fetch_pack(&args, data->fd, data->conn,
547                           refs_tmp ? refs_tmp : transport->remote_refs,
548                           dest, to_fetch, nr_heads, &data->shallow,
549                           &transport->pack_lockfile);
550         close(data->fd[0]);
551         close(data->fd[1]);
552         if (finish_connect(data->conn)) {
553                 free_refs(refs);
554                 refs = NULL;
555         }
556         data->conn = NULL;
557         data->got_remote_heads = 0;
558         data->options.self_contained_and_connected =
559                 args.self_contained_and_connected;
560
561         free_refs(refs_tmp);
562         free_refs(refs);
563         free(dest);
564         return (refs ? 0 : -1);
565 }
566
567 static int push_had_errors(struct ref *ref)
568 {
569         for (; ref; ref = ref->next) {
570                 switch (ref->status) {
571                 case REF_STATUS_NONE:
572                 case REF_STATUS_UPTODATE:
573                 case REF_STATUS_OK:
574                         break;
575                 default:
576                         return 1;
577                 }
578         }
579         return 0;
580 }
581
582 int transport_refs_pushed(struct ref *ref)
583 {
584         for (; ref; ref = ref->next) {
585                 switch(ref->status) {
586                 case REF_STATUS_NONE:
587                 case REF_STATUS_UPTODATE:
588                         break;
589                 default:
590                         return 1;
591                 }
592         }
593         return 0;
594 }
595
596 void transport_update_tracking_ref(struct remote *remote, struct ref *ref, int verbose)
597 {
598         struct refspec rs;
599
600         if (ref->status != REF_STATUS_OK && ref->status != REF_STATUS_UPTODATE)
601                 return;
602
603         rs.src = ref->name;
604         rs.dst = NULL;
605
606         if (!remote_find_tracking(remote, &rs)) {
607                 if (verbose)
608                         fprintf(stderr, "updating local tracking ref '%s'\n", rs.dst);
609                 if (ref->deletion) {
610                         delete_ref(rs.dst, NULL, 0);
611                 } else
612                         update_ref("update by push", rs.dst,
613                                         ref->new_oid.hash, NULL, 0, 0);
614                 free(rs.dst);
615         }
616 }
617
618 static void print_ref_status(char flag, const char *summary, struct ref *to, struct ref *from, const char *msg, int porcelain)
619 {
620         if (porcelain) {
621                 if (from)
622                         fprintf(stdout, "%c\t%s:%s\t", flag, from->name, to->name);
623                 else
624                         fprintf(stdout, "%c\t:%s\t", flag, to->name);
625                 if (msg)
626                         fprintf(stdout, "%s (%s)\n", summary, msg);
627                 else
628                         fprintf(stdout, "%s\n", summary);
629         } else {
630                 fprintf(stderr, " %c %-*s ", flag, TRANSPORT_SUMMARY_WIDTH, summary);
631                 if (from)
632                         fprintf(stderr, "%s -> %s", prettify_refname(from->name), prettify_refname(to->name));
633                 else
634                         fputs(prettify_refname(to->name), stderr);
635                 if (msg) {
636                         fputs(" (", stderr);
637                         fputs(msg, stderr);
638                         fputc(')', stderr);
639                 }
640                 fputc('\n', stderr);
641         }
642 }
643
644 static const char *status_abbrev(unsigned char sha1[20])
645 {
646         return find_unique_abbrev(sha1, DEFAULT_ABBREV);
647 }
648
649 static void print_ok_ref_status(struct ref *ref, int porcelain)
650 {
651         if (ref->deletion)
652                 print_ref_status('-', "[deleted]", ref, NULL, NULL, porcelain);
653         else if (is_null_oid(&ref->old_oid))
654                 print_ref_status('*',
655                         (starts_with(ref->name, "refs/tags/") ? "[new tag]" :
656                         "[new branch]"),
657                         ref, ref->peer_ref, NULL, porcelain);
658         else {
659                 struct strbuf quickref = STRBUF_INIT;
660                 char type;
661                 const char *msg;
662
663                 strbuf_addstr(&quickref, status_abbrev(ref->old_oid.hash));
664                 if (ref->forced_update) {
665                         strbuf_addstr(&quickref, "...");
666                         type = '+';
667                         msg = "forced update";
668                 } else {
669                         strbuf_addstr(&quickref, "..");
670                         type = ' ';
671                         msg = NULL;
672                 }
673                 strbuf_addstr(&quickref, status_abbrev(ref->new_oid.hash));
674
675                 print_ref_status(type, quickref.buf, ref, ref->peer_ref, msg, porcelain);
676                 strbuf_release(&quickref);
677         }
678 }
679
680 static int print_one_push_status(struct ref *ref, const char *dest, int count, int porcelain)
681 {
682         if (!count)
683                 fprintf(porcelain ? stdout : stderr, "To %s\n", dest);
684
685         switch(ref->status) {
686         case REF_STATUS_NONE:
687                 print_ref_status('X', "[no match]", ref, NULL, NULL, porcelain);
688                 break;
689         case REF_STATUS_REJECT_NODELETE:
690                 print_ref_status('!', "[rejected]", ref, NULL,
691                                                  "remote does not support deleting refs", porcelain);
692                 break;
693         case REF_STATUS_UPTODATE:
694                 print_ref_status('=', "[up to date]", ref,
695                                                  ref->peer_ref, NULL, porcelain);
696                 break;
697         case REF_STATUS_REJECT_NONFASTFORWARD:
698                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
699                                                  "non-fast-forward", porcelain);
700                 break;
701         case REF_STATUS_REJECT_ALREADY_EXISTS:
702                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
703                                                  "already exists", porcelain);
704                 break;
705         case REF_STATUS_REJECT_FETCH_FIRST:
706                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
707                                                  "fetch first", porcelain);
708                 break;
709         case REF_STATUS_REJECT_NEEDS_FORCE:
710                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
711                                                  "needs force", porcelain);
712                 break;
713         case REF_STATUS_REJECT_STALE:
714                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
715                                                  "stale info", porcelain);
716                 break;
717         case REF_STATUS_REJECT_SHALLOW:
718                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
719                                                  "new shallow roots not allowed", porcelain);
720                 break;
721         case REF_STATUS_REMOTE_REJECT:
722                 print_ref_status('!', "[remote rejected]", ref,
723                                                  ref->deletion ? NULL : ref->peer_ref,
724                                                  ref->remote_status, porcelain);
725                 break;
726         case REF_STATUS_EXPECTING_REPORT:
727                 print_ref_status('!', "[remote failure]", ref,
728                                                  ref->deletion ? NULL : ref->peer_ref,
729                                                  "remote failed to report status", porcelain);
730                 break;
731         case REF_STATUS_ATOMIC_PUSH_FAILED:
732                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
733                                                  "atomic push failed", porcelain);
734                 break;
735         case REF_STATUS_OK:
736                 print_ok_ref_status(ref, porcelain);
737                 break;
738         }
739
740         return 1;
741 }
742
743 void transport_print_push_status(const char *dest, struct ref *refs,
744                                   int verbose, int porcelain, unsigned int *reject_reasons)
745 {
746         struct ref *ref;
747         int n = 0;
748         unsigned char head_sha1[20];
749         char *head;
750
751         head = resolve_refdup("HEAD", RESOLVE_REF_READING, head_sha1, NULL);
752
753         if (verbose) {
754                 for (ref = refs; ref; ref = ref->next)
755                         if (ref->status == REF_STATUS_UPTODATE)
756                                 n += print_one_push_status(ref, dest, n, porcelain);
757         }
758
759         for (ref = refs; ref; ref = ref->next)
760                 if (ref->status == REF_STATUS_OK)
761                         n += print_one_push_status(ref, dest, n, porcelain);
762
763         *reject_reasons = 0;
764         for (ref = refs; ref; ref = ref->next) {
765                 if (ref->status != REF_STATUS_NONE &&
766                     ref->status != REF_STATUS_UPTODATE &&
767                     ref->status != REF_STATUS_OK)
768                         n += print_one_push_status(ref, dest, n, porcelain);
769                 if (ref->status == REF_STATUS_REJECT_NONFASTFORWARD) {
770                         if (head != NULL && !strcmp(head, ref->name))
771                                 *reject_reasons |= REJECT_NON_FF_HEAD;
772                         else
773                                 *reject_reasons |= REJECT_NON_FF_OTHER;
774                 } else if (ref->status == REF_STATUS_REJECT_ALREADY_EXISTS) {
775                         *reject_reasons |= REJECT_ALREADY_EXISTS;
776                 } else if (ref->status == REF_STATUS_REJECT_FETCH_FIRST) {
777                         *reject_reasons |= REJECT_FETCH_FIRST;
778                 } else if (ref->status == REF_STATUS_REJECT_NEEDS_FORCE) {
779                         *reject_reasons |= REJECT_NEEDS_FORCE;
780                 }
781         }
782         free(head);
783 }
784
785 void transport_verify_remote_names(int nr_heads, const char **heads)
786 {
787         int i;
788
789         for (i = 0; i < nr_heads; i++) {
790                 const char *local = heads[i];
791                 const char *remote = strrchr(heads[i], ':');
792
793                 if (*local == '+')
794                         local++;
795
796                 /* A matching refspec is okay.  */
797                 if (remote == local && remote[1] == '\0')
798                         continue;
799
800                 remote = remote ? (remote + 1) : local;
801                 if (check_refname_format(remote,
802                                 REFNAME_ALLOW_ONELEVEL|REFNAME_REFSPEC_PATTERN))
803                         die("remote part of refspec is not a valid name in %s",
804                                 heads[i]);
805         }
806 }
807
808 static int git_transport_push(struct transport *transport, struct ref *remote_refs, int flags)
809 {
810         struct git_transport_data *data = transport->data;
811         struct send_pack_args args;
812         int ret;
813
814         if (!data->got_remote_heads) {
815                 struct ref *tmp_refs;
816                 connect_setup(transport, 1);
817
818                 get_remote_heads(data->fd[0], NULL, 0, &tmp_refs, REF_NORMAL,
819                                  NULL, &data->shallow);
820                 data->got_remote_heads = 1;
821         }
822
823         memset(&args, 0, sizeof(args));
824         args.send_mirror = !!(flags & TRANSPORT_PUSH_MIRROR);
825         args.force_update = !!(flags & TRANSPORT_PUSH_FORCE);
826         args.use_thin_pack = data->options.thin;
827         args.verbose = (transport->verbose > 0);
828         args.quiet = (transport->verbose < 0);
829         args.progress = transport->progress;
830         args.dry_run = !!(flags & TRANSPORT_PUSH_DRY_RUN);
831         args.porcelain = !!(flags & TRANSPORT_PUSH_PORCELAIN);
832         args.atomic = !!(flags & TRANSPORT_PUSH_ATOMIC);
833         args.url = transport->url;
834
835         if (flags & TRANSPORT_PUSH_CERT_ALWAYS)
836                 args.push_cert = SEND_PACK_PUSH_CERT_ALWAYS;
837         else if (flags & TRANSPORT_PUSH_CERT_IF_ASKED)
838                 args.push_cert = SEND_PACK_PUSH_CERT_IF_ASKED;
839         else
840                 args.push_cert = SEND_PACK_PUSH_CERT_NEVER;
841
842         ret = send_pack(&args, data->fd, data->conn, remote_refs,
843                         &data->extra_have);
844
845         close(data->fd[1]);
846         close(data->fd[0]);
847         ret |= finish_connect(data->conn);
848         data->conn = NULL;
849         data->got_remote_heads = 0;
850
851         return ret;
852 }
853
854 static int connect_git(struct transport *transport, const char *name,
855                        const char *executable, int fd[2])
856 {
857         struct git_transport_data *data = transport->data;
858         data->conn = git_connect(data->fd, transport->url,
859                                  executable, 0);
860         fd[0] = data->fd[0];
861         fd[1] = data->fd[1];
862         return 0;
863 }
864
865 static int disconnect_git(struct transport *transport)
866 {
867         struct git_transport_data *data = transport->data;
868         if (data->conn) {
869                 if (data->got_remote_heads)
870                         packet_flush(data->fd[1]);
871                 close(data->fd[0]);
872                 close(data->fd[1]);
873                 finish_connect(data->conn);
874         }
875
876         free(data);
877         return 0;
878 }
879
880 void transport_take_over(struct transport *transport,
881                          struct child_process *child)
882 {
883         struct git_transport_data *data;
884
885         if (!transport->smart_options)
886                 die("Bug detected: Taking over transport requires non-NULL "
887                     "smart_options field.");
888
889         data = xcalloc(1, sizeof(*data));
890         data->options = *transport->smart_options;
891         data->conn = child;
892         data->fd[0] = data->conn->out;
893         data->fd[1] = data->conn->in;
894         data->got_remote_heads = 0;
895         transport->data = data;
896
897         transport->set_option = NULL;
898         transport->get_refs_list = get_refs_via_connect;
899         transport->fetch = fetch_refs_via_pack;
900         transport->push = NULL;
901         transport->push_refs = git_transport_push;
902         transport->disconnect = disconnect_git;
903         transport->smart_options = &(data->options);
904
905         transport->cannot_reuse = 1;
906 }
907
908 static int is_file(const char *url)
909 {
910         struct stat buf;
911         if (stat(url, &buf))
912                 return 0;
913         return S_ISREG(buf.st_mode);
914 }
915
916 static int external_specification_len(const char *url)
917 {
918         return strchr(url, ':') - url;
919 }
920
921 static const struct string_list *protocol_whitelist(void)
922 {
923         static int enabled = -1;
924         static struct string_list allowed = STRING_LIST_INIT_DUP;
925
926         if (enabled < 0) {
927                 const char *v = getenv("GIT_ALLOW_PROTOCOL");
928                 if (v) {
929                         string_list_split(&allowed, v, ':', -1);
930                         string_list_sort(&allowed);
931                         enabled = 1;
932                 } else {
933                         enabled = 0;
934                 }
935         }
936
937         return enabled ? &allowed : NULL;
938 }
939
940 int is_transport_allowed(const char *type)
941 {
942         const struct string_list *allowed = protocol_whitelist();
943         return !allowed || string_list_has_string(allowed, type);
944 }
945
946 void transport_check_allowed(const char *type)
947 {
948         if (!is_transport_allowed(type))
949                 die("transport '%s' not allowed", type);
950 }
951
952 int transport_restrict_protocols(void)
953 {
954         return !!protocol_whitelist();
955 }
956
957 struct transport *transport_get(struct remote *remote, const char *url)
958 {
959         const char *helper;
960         struct transport *ret = xcalloc(1, sizeof(*ret));
961
962         ret->progress = isatty(2);
963
964         if (!remote)
965                 die("No remote provided to transport_get()");
966
967         ret->got_remote_refs = 0;
968         ret->remote = remote;
969         helper = remote->foreign_vcs;
970
971         if (!url && remote->url)
972                 url = remote->url[0];
973         ret->url = url;
974
975         /* maybe it is a foreign URL? */
976         if (url) {
977                 const char *p = url;
978
979                 while (is_urlschemechar(p == url, *p))
980                         p++;
981                 if (starts_with(p, "::"))
982                         helper = xstrndup(url, p - url);
983         }
984
985         if (helper) {
986                 transport_helper_init(ret, helper);
987         } else if (starts_with(url, "rsync:")) {
988                 transport_check_allowed("rsync");
989                 ret->get_refs_list = get_refs_via_rsync;
990                 ret->fetch = fetch_objs_via_rsync;
991                 ret->push = rsync_transport_push;
992                 ret->smart_options = NULL;
993         } else if (url_is_local_not_ssh(url) && is_file(url) && is_bundle(url, 1)) {
994                 struct bundle_transport_data *data = xcalloc(1, sizeof(*data));
995                 transport_check_allowed("file");
996                 ret->data = data;
997                 ret->get_refs_list = get_refs_from_bundle;
998                 ret->fetch = fetch_refs_from_bundle;
999                 ret->disconnect = close_bundle;
1000                 ret->smart_options = NULL;
1001         } else if (!is_url(url)
1002                 || starts_with(url, "file://")
1003                 || starts_with(url, "git://")
1004                 || starts_with(url, "ssh://")
1005                 || starts_with(url, "git+ssh://")
1006                 || starts_with(url, "ssh+git://")) {
1007                 /*
1008                  * These are builtin smart transports; "allowed" transports
1009                  * will be checked individually in git_connect.
1010                  */
1011                 struct git_transport_data *data = xcalloc(1, sizeof(*data));
1012                 ret->data = data;
1013                 ret->set_option = NULL;
1014                 ret->get_refs_list = get_refs_via_connect;
1015                 ret->fetch = fetch_refs_via_pack;
1016                 ret->push_refs = git_transport_push;
1017                 ret->connect = connect_git;
1018                 ret->disconnect = disconnect_git;
1019                 ret->smart_options = &(data->options);
1020
1021                 data->conn = NULL;
1022                 data->got_remote_heads = 0;
1023         } else {
1024                 /* Unknown protocol in URL. Pass to external handler. */
1025                 int len = external_specification_len(url);
1026                 char *handler = xmemdupz(url, len);
1027                 transport_helper_init(ret, handler);
1028         }
1029
1030         if (ret->smart_options) {
1031                 ret->smart_options->thin = 1;
1032                 ret->smart_options->uploadpack = "git-upload-pack";
1033                 if (remote->uploadpack)
1034                         ret->smart_options->uploadpack = remote->uploadpack;
1035                 ret->smart_options->receivepack = "git-receive-pack";
1036                 if (remote->receivepack)
1037                         ret->smart_options->receivepack = remote->receivepack;
1038         }
1039
1040         return ret;
1041 }
1042
1043 int transport_set_option(struct transport *transport,
1044                          const char *name, const char *value)
1045 {
1046         int git_reports = 1, protocol_reports = 1;
1047
1048         if (transport->smart_options)
1049                 git_reports = set_git_option(transport->smart_options,
1050                                              name, value);
1051
1052         if (transport->set_option)
1053                 protocol_reports = transport->set_option(transport, name,
1054                                                         value);
1055
1056         /* If either report is 0, report 0 (success). */
1057         if (!git_reports || !protocol_reports)
1058                 return 0;
1059         /* If either reports -1 (invalid value), report -1. */
1060         if ((git_reports == -1) || (protocol_reports == -1))
1061                 return -1;
1062         /* Otherwise if both report unknown, report unknown. */
1063         return 1;
1064 }
1065
1066 void transport_set_verbosity(struct transport *transport, int verbosity,
1067         int force_progress)
1068 {
1069         if (verbosity >= 1)
1070                 transport->verbose = verbosity <= 3 ? verbosity : 3;
1071         if (verbosity < 0)
1072                 transport->verbose = -1;
1073
1074         /**
1075          * Rules used to determine whether to report progress (processing aborts
1076          * when a rule is satisfied):
1077          *
1078          *   . Report progress, if force_progress is 1 (ie. --progress).
1079          *   . Don't report progress, if force_progress is 0 (ie. --no-progress).
1080          *   . Don't report progress, if verbosity < 0 (ie. -q/--quiet ).
1081          *   . Report progress if isatty(2) is 1.
1082          **/
1083         if (force_progress >= 0)
1084                 transport->progress = !!force_progress;
1085         else
1086                 transport->progress = verbosity >= 0 && isatty(2);
1087 }
1088
1089 static void die_with_unpushed_submodules(struct string_list *needs_pushing)
1090 {
1091         int i;
1092
1093         fprintf(stderr, "The following submodule paths contain changes that can\n"
1094                         "not be found on any remote:\n");
1095         for (i = 0; i < needs_pushing->nr; i++)
1096                 printf("  %s\n", needs_pushing->items[i].string);
1097         fprintf(stderr, "\nPlease try\n\n"
1098                         "       git push --recurse-submodules=on-demand\n\n"
1099                         "or cd to the path and use\n\n"
1100                         "       git push\n\n"
1101                         "to push them to a remote.\n\n");
1102
1103         string_list_clear(needs_pushing, 0);
1104
1105         die("Aborting.");
1106 }
1107
1108 static int run_pre_push_hook(struct transport *transport,
1109                              struct ref *remote_refs)
1110 {
1111         int ret = 0, x;
1112         struct ref *r;
1113         struct child_process proc = CHILD_PROCESS_INIT;
1114         struct strbuf buf;
1115         const char *argv[4];
1116
1117         if (!(argv[0] = find_hook("pre-push")))
1118                 return 0;
1119
1120         argv[1] = transport->remote->name;
1121         argv[2] = transport->url;
1122         argv[3] = NULL;
1123
1124         proc.argv = argv;
1125         proc.in = -1;
1126
1127         if (start_command(&proc)) {
1128                 finish_command(&proc);
1129                 return -1;
1130         }
1131
1132         sigchain_push(SIGPIPE, SIG_IGN);
1133
1134         strbuf_init(&buf, 256);
1135
1136         for (r = remote_refs; r; r = r->next) {
1137                 if (!r->peer_ref) continue;
1138                 if (r->status == REF_STATUS_REJECT_NONFASTFORWARD) continue;
1139                 if (r->status == REF_STATUS_REJECT_STALE) continue;
1140                 if (r->status == REF_STATUS_UPTODATE) continue;
1141
1142                 strbuf_reset(&buf);
1143                 strbuf_addf( &buf, "%s %s %s %s\n",
1144                          r->peer_ref->name, oid_to_hex(&r->new_oid),
1145                          r->name, oid_to_hex(&r->old_oid));
1146
1147                 if (write_in_full(proc.in, buf.buf, buf.len) < 0) {
1148                         /* We do not mind if a hook does not read all refs. */
1149                         if (errno != EPIPE)
1150                                 ret = -1;
1151                         break;
1152                 }
1153         }
1154
1155         strbuf_release(&buf);
1156
1157         x = close(proc.in);
1158         if (!ret)
1159                 ret = x;
1160
1161         sigchain_pop(SIGPIPE);
1162
1163         x = finish_command(&proc);
1164         if (!ret)
1165                 ret = x;
1166
1167         return ret;
1168 }
1169
1170 int transport_push(struct transport *transport,
1171                    int refspec_nr, const char **refspec, int flags,
1172                    unsigned int *reject_reasons)
1173 {
1174         *reject_reasons = 0;
1175         transport_verify_remote_names(refspec_nr, refspec);
1176
1177         if (transport->push) {
1178                 /* Maybe FIXME. But no important transport uses this case. */
1179                 if (flags & TRANSPORT_PUSH_SET_UPSTREAM)
1180                         die("This transport does not support using --set-upstream");
1181
1182                 return transport->push(transport, refspec_nr, refspec, flags);
1183         } else if (transport->push_refs) {
1184                 struct ref *remote_refs;
1185                 struct ref *local_refs = get_local_heads();
1186                 int match_flags = MATCH_REFS_NONE;
1187                 int verbose = (transport->verbose > 0);
1188                 int quiet = (transport->verbose < 0);
1189                 int porcelain = flags & TRANSPORT_PUSH_PORCELAIN;
1190                 int pretend = flags & TRANSPORT_PUSH_DRY_RUN;
1191                 int push_ret, ret, err;
1192
1193                 if (check_push_refs(local_refs, refspec_nr, refspec) < 0)
1194                         return -1;
1195
1196                 remote_refs = transport->get_refs_list(transport, 1);
1197
1198                 if (flags & TRANSPORT_PUSH_ALL)
1199                         match_flags |= MATCH_REFS_ALL;
1200                 if (flags & TRANSPORT_PUSH_MIRROR)
1201                         match_flags |= MATCH_REFS_MIRROR;
1202                 if (flags & TRANSPORT_PUSH_PRUNE)
1203                         match_flags |= MATCH_REFS_PRUNE;
1204                 if (flags & TRANSPORT_PUSH_FOLLOW_TAGS)
1205                         match_flags |= MATCH_REFS_FOLLOW_TAGS;
1206
1207                 if (match_push_refs(local_refs, &remote_refs,
1208                                     refspec_nr, refspec, match_flags)) {
1209                         return -1;
1210                 }
1211
1212                 if (transport->smart_options &&
1213                     transport->smart_options->cas &&
1214                     !is_empty_cas(transport->smart_options->cas))
1215                         apply_push_cas(transport->smart_options->cas,
1216                                        transport->remote, remote_refs);
1217
1218                 set_ref_status_for_push(remote_refs,
1219                         flags & TRANSPORT_PUSH_MIRROR,
1220                         flags & TRANSPORT_PUSH_FORCE);
1221
1222                 if (!(flags & TRANSPORT_PUSH_NO_HOOK))
1223                         if (run_pre_push_hook(transport, remote_refs))
1224                                 return -1;
1225
1226                 if ((flags & TRANSPORT_RECURSE_SUBMODULES_ON_DEMAND) && !is_bare_repository()) {
1227                         struct ref *ref = remote_refs;
1228                         for (; ref; ref = ref->next)
1229                                 if (!is_null_oid(&ref->new_oid) &&
1230                                     !push_unpushed_submodules(ref->new_oid.hash,
1231                                             transport->remote->name))
1232                                     die ("Failed to push all needed submodules!");
1233                 }
1234
1235                 if ((flags & (TRANSPORT_RECURSE_SUBMODULES_ON_DEMAND |
1236                               TRANSPORT_RECURSE_SUBMODULES_CHECK)) && !is_bare_repository()) {
1237                         struct ref *ref = remote_refs;
1238                         struct string_list needs_pushing = STRING_LIST_INIT_DUP;
1239
1240                         for (; ref; ref = ref->next)
1241                                 if (!is_null_oid(&ref->new_oid) &&
1242                                     find_unpushed_submodules(ref->new_oid.hash,
1243                                             transport->remote->name, &needs_pushing))
1244                                         die_with_unpushed_submodules(&needs_pushing);
1245                 }
1246
1247                 push_ret = transport->push_refs(transport, remote_refs, flags);
1248                 err = push_had_errors(remote_refs);
1249                 ret = push_ret | err;
1250
1251                 if (!quiet || err)
1252                         transport_print_push_status(transport->url, remote_refs,
1253                                         verbose | porcelain, porcelain,
1254                                         reject_reasons);
1255
1256                 if (flags & TRANSPORT_PUSH_SET_UPSTREAM)
1257                         set_upstreams(transport, remote_refs, pretend);
1258
1259                 if (!(flags & TRANSPORT_PUSH_DRY_RUN)) {
1260                         struct ref *ref;
1261                         for (ref = remote_refs; ref; ref = ref->next)
1262                                 transport_update_tracking_ref(transport->remote, ref, verbose);
1263                 }
1264
1265                 if (porcelain && !push_ret)
1266                         puts("Done");
1267                 else if (!quiet && !ret && !transport_refs_pushed(remote_refs))
1268                         fprintf(stderr, "Everything up-to-date\n");
1269
1270                 return ret;
1271         }
1272         return 1;
1273 }
1274
1275 const struct ref *transport_get_remote_refs(struct transport *transport)
1276 {
1277         if (!transport->got_remote_refs) {
1278                 transport->remote_refs = transport->get_refs_list(transport, 0);
1279                 transport->got_remote_refs = 1;
1280         }
1281
1282         return transport->remote_refs;
1283 }
1284
1285 int transport_fetch_refs(struct transport *transport, struct ref *refs)
1286 {
1287         int rc;
1288         int nr_heads = 0, nr_alloc = 0, nr_refs = 0;
1289         struct ref **heads = NULL;
1290         struct ref *rm;
1291
1292         for (rm = refs; rm; rm = rm->next) {
1293                 nr_refs++;
1294                 if (rm->peer_ref &&
1295                     !is_null_oid(&rm->old_oid) &&
1296                     !oidcmp(&rm->peer_ref->old_oid, &rm->old_oid))
1297                         continue;
1298                 ALLOC_GROW(heads, nr_heads + 1, nr_alloc);
1299                 heads[nr_heads++] = rm;
1300         }
1301
1302         if (!nr_heads) {
1303                 /*
1304                  * When deepening of a shallow repository is requested,
1305                  * then local and remote refs are likely to still be equal.
1306                  * Just feed them all to the fetch method in that case.
1307                  * This condition shouldn't be met in a non-deepening fetch
1308                  * (see builtin/fetch.c:quickfetch()).
1309                  */
1310                 heads = xmalloc(nr_refs * sizeof(*heads));
1311                 for (rm = refs; rm; rm = rm->next)
1312                         heads[nr_heads++] = rm;
1313         }
1314
1315         rc = transport->fetch(transport, nr_heads, heads);
1316
1317         free(heads);
1318         return rc;
1319 }
1320
1321 void transport_unlock_pack(struct transport *transport)
1322 {
1323         if (transport->pack_lockfile) {
1324                 unlink_or_warn(transport->pack_lockfile);
1325                 free(transport->pack_lockfile);
1326                 transport->pack_lockfile = NULL;
1327         }
1328 }
1329
1330 int transport_connect(struct transport *transport, const char *name,
1331                       const char *exec, int fd[2])
1332 {
1333         if (transport->connect)
1334                 return transport->connect(transport, name, exec, fd);
1335         else
1336                 die("Operation not supported by protocol");
1337 }
1338
1339 int transport_disconnect(struct transport *transport)
1340 {
1341         int ret = 0;
1342         if (transport->disconnect)
1343                 ret = transport->disconnect(transport);
1344         free(transport);
1345         return ret;
1346 }
1347
1348 /*
1349  * Strip username (and password) from a URL and return
1350  * it in a newly allocated string.
1351  */
1352 char *transport_anonymize_url(const char *url)
1353 {
1354         char *anon_url, *scheme_prefix, *anon_part;
1355         size_t anon_len, prefix_len = 0;
1356
1357         anon_part = strchr(url, '@');
1358         if (url_is_local_not_ssh(url) || !anon_part)
1359                 goto literal_copy;
1360
1361         anon_len = strlen(++anon_part);
1362         scheme_prefix = strstr(url, "://");
1363         if (!scheme_prefix) {
1364                 if (!strchr(anon_part, ':'))
1365                         /* cannot be "me@there:/path/name" */
1366                         goto literal_copy;
1367         } else {
1368                 const char *cp;
1369                 /* make sure scheme is reasonable */
1370                 for (cp = url; cp < scheme_prefix; cp++) {
1371                         switch (*cp) {
1372                                 /* RFC 1738 2.1 */
1373                         case '+': case '.': case '-':
1374                                 break; /* ok */
1375                         default:
1376                                 if (isalnum(*cp))
1377                                         break;
1378                                 /* it isn't */
1379                                 goto literal_copy;
1380                         }
1381                 }
1382                 /* @ past the first slash does not count */
1383                 cp = strchr(scheme_prefix + 3, '/');
1384                 if (cp && cp < anon_part)
1385                         goto literal_copy;
1386                 prefix_len = scheme_prefix - url + 3;
1387         }
1388         anon_url = xcalloc(1, 1 + prefix_len + anon_len);
1389         memcpy(anon_url, url, prefix_len);
1390         memcpy(anon_url + prefix_len, anon_part, anon_len);
1391         return anon_url;
1392 literal_copy:
1393         return xstrdup(url);
1394 }
1395
1396 struct alternate_refs_data {
1397         alternate_ref_fn *fn;
1398         void *data;
1399 };
1400
1401 static int refs_from_alternate_cb(struct alternate_object_database *e,
1402                                   void *data)
1403 {
1404         char *other;
1405         size_t len;
1406         struct remote *remote;
1407         struct transport *transport;
1408         const struct ref *extra;
1409         struct alternate_refs_data *cb = data;
1410
1411         e->name[-1] = '\0';
1412         other = xstrdup(real_path(e->base));
1413         e->name[-1] = '/';
1414         len = strlen(other);
1415
1416         while (other[len-1] == '/')
1417                 other[--len] = '\0';
1418         if (len < 8 || memcmp(other + len - 8, "/objects", 8))
1419                 goto out;
1420         /* Is this a git repository with refs? */
1421         memcpy(other + len - 8, "/refs", 6);
1422         if (!is_directory(other))
1423                 goto out;
1424         other[len - 8] = '\0';
1425         remote = remote_get(other);
1426         transport = transport_get(remote, other);
1427         for (extra = transport_get_remote_refs(transport);
1428              extra;
1429              extra = extra->next)
1430                 cb->fn(extra, cb->data);
1431         transport_disconnect(transport);
1432 out:
1433         free(other);
1434         return 0;
1435 }
1436
1437 void for_each_alternate_ref(alternate_ref_fn fn, void *data)
1438 {
1439         struct alternate_refs_data cb;
1440         cb.fn = fn;
1441         cb.data = data;
1442         foreach_alt_odb(refs_from_alternate_cb, &cb);
1443 }