Merge branch 'pt/am-builtin'
[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
19 /* rsync support */
20
21 /*
22  * We copy packed-refs and refs/ into a temporary file, then read the
23  * loose refs recursively (sorting whenever possible), and then inserting
24  * those packed refs that are not yet in the list (not validating, but
25  * assuming that the file is sorted).
26  *
27  * Appears refactoring this from refs.c is too cumbersome.
28  */
29
30 static int str_cmp(const void *a, const void *b)
31 {
32         const char *s1 = a;
33         const char *s2 = b;
34
35         return strcmp(s1, s2);
36 }
37
38 /* path->buf + name_offset is expected to point to "refs/" */
39
40 static int read_loose_refs(struct strbuf *path, int name_offset,
41                 struct ref **tail)
42 {
43         DIR *dir = opendir(path->buf);
44         struct dirent *de;
45         struct {
46                 char **entries;
47                 int nr, alloc;
48         } list;
49         int i, pathlen;
50
51         if (!dir)
52                 return -1;
53
54         memset (&list, 0, sizeof(list));
55
56         while ((de = readdir(dir))) {
57                 if (is_dot_or_dotdot(de->d_name))
58                         continue;
59                 ALLOC_GROW(list.entries, list.nr + 1, list.alloc);
60                 list.entries[list.nr++] = xstrdup(de->d_name);
61         }
62         closedir(dir);
63
64         /* sort the list */
65
66         qsort(list.entries, list.nr, sizeof(char *), str_cmp);
67
68         pathlen = path->len;
69         strbuf_addch(path, '/');
70
71         for (i = 0; i < list.nr; i++, strbuf_setlen(path, pathlen + 1)) {
72                 strbuf_addstr(path, list.entries[i]);
73                 if (read_loose_refs(path, name_offset, tail)) {
74                         int fd = open(path->buf, O_RDONLY);
75                         char buffer[40];
76                         struct ref *next;
77
78                         if (fd < 0)
79                                 continue;
80                         next = alloc_ref(path->buf + name_offset);
81                         if (read_in_full(fd, buffer, 40) != 40 ||
82                                         get_sha1_hex(buffer, next->old_sha1)) {
83                                 close(fd);
84                                 free(next);
85                                 continue;
86                         }
87                         close(fd);
88                         (*tail)->next = next;
89                         *tail = next;
90                 }
91         }
92         strbuf_setlen(path, pathlen);
93
94         for (i = 0; i < list.nr; i++)
95                 free(list.entries[i]);
96         free(list.entries);
97
98         return 0;
99 }
100
101 /* insert the packed refs for which no loose refs were found */
102
103 static void insert_packed_refs(const char *packed_refs, struct ref **list)
104 {
105         FILE *f = fopen(packed_refs, "r");
106         static char buffer[PATH_MAX];
107
108         if (!f)
109                 return;
110
111         for (;;) {
112                 int cmp = 0; /* assigned before used */
113                 int len;
114
115                 if (!fgets(buffer, sizeof(buffer), f)) {
116                         fclose(f);
117                         return;
118                 }
119
120                 if (!isxdigit(buffer[0]))
121                         continue;
122                 len = strlen(buffer);
123                 if (len && buffer[len - 1] == '\n')
124                         buffer[--len] = '\0';
125                 if (len < 41)
126                         continue;
127                 while ((*list)->next &&
128                                 (cmp = strcmp(buffer + 41,
129                                       (*list)->next->name)) > 0)
130                         list = &(*list)->next;
131                 if (!(*list)->next || cmp < 0) {
132                         struct ref *next = alloc_ref(buffer + 41);
133                         buffer[40] = '\0';
134                         if (get_sha1_hex(buffer, next->old_sha1)) {
135                                 warning ("invalid SHA-1: %s", buffer);
136                                 free(next);
137                                 continue;
138                         }
139                         next->next = (*list)->next;
140                         (*list)->next = next;
141                         list = &(*list)->next;
142                 }
143         }
144 }
145
146 static void set_upstreams(struct transport *transport, struct ref *refs,
147         int pretend)
148 {
149         struct ref *ref;
150         for (ref = refs; ref; ref = ref->next) {
151                 const char *localname;
152                 const char *tmp;
153                 const char *remotename;
154                 unsigned char sha[20];
155                 int flag = 0;
156                 /*
157                  * Check suitability for tracking. Must be successful /
158                  * already up-to-date ref create/modify (not delete).
159                  */
160                 if (ref->status != REF_STATUS_OK &&
161                         ref->status != REF_STATUS_UPTODATE)
162                         continue;
163                 if (!ref->peer_ref)
164                         continue;
165                 if (is_null_sha1(ref->new_sha1))
166                         continue;
167
168                 /* Follow symbolic refs (mainly for HEAD). */
169                 localname = ref->peer_ref->name;
170                 remotename = ref->name;
171                 tmp = resolve_ref_unsafe(localname, RESOLVE_REF_READING,
172                                          sha, &flag);
173                 if (tmp && flag & REF_ISSYMREF &&
174                         starts_with(tmp, "refs/heads/"))
175                         localname = tmp;
176
177                 /* Both source and destination must be local branches. */
178                 if (!localname || !starts_with(localname, "refs/heads/"))
179                         continue;
180                 if (!remotename || !starts_with(remotename, "refs/heads/"))
181                         continue;
182
183                 if (!pretend)
184                         install_branch_config(BRANCH_CONFIG_VERBOSE,
185                                 localname + 11, transport->remote->name,
186                                 remotename);
187                 else
188                         printf("Would set upstream of '%s' to '%s' of '%s'\n",
189                                 localname + 11, remotename + 11,
190                                 transport->remote->name);
191         }
192 }
193
194 static const char *rsync_url(const char *url)
195 {
196         if (!starts_with(url, "rsync://"))
197                 skip_prefix(url, "rsync:", &url);
198         return url;
199 }
200
201 static struct ref *get_refs_via_rsync(struct transport *transport, int for_push)
202 {
203         struct strbuf buf = STRBUF_INIT, temp_dir = STRBUF_INIT;
204         struct ref dummy = {NULL}, *tail = &dummy;
205         struct child_process rsync = CHILD_PROCESS_INIT;
206         const char *args[5];
207         int temp_dir_len;
208
209         if (for_push)
210                 return NULL;
211
212         /* copy the refs to the temporary directory */
213
214         strbuf_addstr(&temp_dir, git_path("rsync-refs-XXXXXX"));
215         if (!mkdtemp(temp_dir.buf))
216                 die_errno ("Could not make temporary directory");
217         temp_dir_len = temp_dir.len;
218
219         strbuf_addstr(&buf, rsync_url(transport->url));
220         strbuf_addstr(&buf, "/refs");
221
222         rsync.argv = args;
223         rsync.stdout_to_stderr = 1;
224         args[0] = "rsync";
225         args[1] = (transport->verbose > 1) ? "-rv" : "-r";
226         args[2] = buf.buf;
227         args[3] = temp_dir.buf;
228         args[4] = NULL;
229
230         if (run_command(&rsync))
231                 die ("Could not run rsync to get refs");
232
233         strbuf_reset(&buf);
234         strbuf_addstr(&buf, rsync_url(transport->url));
235         strbuf_addstr(&buf, "/packed-refs");
236
237         args[2] = buf.buf;
238
239         if (run_command(&rsync))
240                 die ("Could not run rsync to get refs");
241
242         /* read the copied refs */
243
244         strbuf_addstr(&temp_dir, "/refs");
245         read_loose_refs(&temp_dir, temp_dir_len + 1, &tail);
246         strbuf_setlen(&temp_dir, temp_dir_len);
247
248         tail = &dummy;
249         strbuf_addstr(&temp_dir, "/packed-refs");
250         insert_packed_refs(temp_dir.buf, &tail);
251         strbuf_setlen(&temp_dir, temp_dir_len);
252
253         if (remove_dir_recursively(&temp_dir, 0))
254                 warning ("Error removing temporary directory %s.",
255                                 temp_dir.buf);
256
257         strbuf_release(&buf);
258         strbuf_release(&temp_dir);
259
260         return dummy.next;
261 }
262
263 static int fetch_objs_via_rsync(struct transport *transport,
264                                 int nr_objs, struct ref **to_fetch)
265 {
266         struct child_process rsync = CHILD_PROCESS_INIT;
267
268         rsync.stdout_to_stderr = 1;
269         argv_array_push(&rsync.args, "rsync");
270         argv_array_push(&rsync.args, (transport->verbose > 1) ? "-rv" : "-r");
271         argv_array_push(&rsync.args, "--ignore-existing");
272         argv_array_push(&rsync.args, "--exclude");
273         argv_array_push(&rsync.args, "info");
274         argv_array_pushf(&rsync.args, "%s/objects/", rsync_url(transport->url));
275         argv_array_push(&rsync.args, get_object_directory());
276
277         /* NEEDSWORK: handle one level of alternates */
278         return run_command(&rsync);
279 }
280
281 static int write_one_ref(const char *name, const struct object_id *oid,
282                          int flags, void *data)
283 {
284         struct strbuf *buf = data;
285         int len = buf->len;
286
287         /* when called via for_each_ref(), flags is non-zero */
288         if (flags && !starts_with(name, "refs/heads/") &&
289                         !starts_with(name, "refs/tags/"))
290                 return 0;
291
292         strbuf_addstr(buf, name);
293         if (safe_create_leading_directories(buf->buf) ||
294             write_file_gently(buf->buf, "%s", oid_to_hex(oid)))
295                 return error("problems writing temporary file %s: %s",
296                              buf->buf, strerror(errno));
297         strbuf_setlen(buf, len);
298         return 0;
299 }
300
301 static int write_refs_to_temp_dir(struct strbuf *temp_dir,
302                                   int refspec_nr, const char **refspec)
303 {
304         int i;
305
306         for (i = 0; i < refspec_nr; i++) {
307                 struct object_id oid;
308                 char *ref;
309
310                 if (dwim_ref(refspec[i], strlen(refspec[i]), oid.hash, &ref) != 1)
311                         return error("Could not get ref %s", refspec[i]);
312
313                 if (write_one_ref(ref, &oid, 0, temp_dir)) {
314                         free(ref);
315                         return -1;
316                 }
317                 free(ref);
318         }
319         return 0;
320 }
321
322 static int rsync_transport_push(struct transport *transport,
323                 int refspec_nr, const char **refspec, int flags)
324 {
325         struct strbuf buf = STRBUF_INIT, temp_dir = STRBUF_INIT;
326         int result = 0, i;
327         struct child_process rsync = CHILD_PROCESS_INIT;
328         const char *args[10];
329
330         if (flags & TRANSPORT_PUSH_MIRROR)
331                 return error("rsync transport does not support mirror mode");
332
333         /* first push the objects */
334
335         strbuf_addstr(&buf, rsync_url(transport->url));
336         strbuf_addch(&buf, '/');
337
338         rsync.argv = args;
339         rsync.stdout_to_stderr = 1;
340         i = 0;
341         args[i++] = "rsync";
342         args[i++] = "-a";
343         if (flags & TRANSPORT_PUSH_DRY_RUN)
344                 args[i++] = "--dry-run";
345         if (transport->verbose > 1)
346                 args[i++] = "-v";
347         args[i++] = "--ignore-existing";
348         args[i++] = "--exclude";
349         args[i++] = "info";
350         args[i++] = get_object_directory();
351         args[i++] = buf.buf;
352         args[i++] = NULL;
353
354         if (run_command(&rsync))
355                 return error("Could not push objects to %s",
356                                 rsync_url(transport->url));
357
358         /* copy the refs to the temporary directory; they could be packed. */
359
360         strbuf_addstr(&temp_dir, git_path("rsync-refs-XXXXXX"));
361         if (!mkdtemp(temp_dir.buf))
362                 die_errno ("Could not make temporary directory");
363         strbuf_addch(&temp_dir, '/');
364
365         if (flags & TRANSPORT_PUSH_ALL) {
366                 if (for_each_ref(write_one_ref, &temp_dir))
367                         return -1;
368         } else if (write_refs_to_temp_dir(&temp_dir, refspec_nr, refspec))
369                 return -1;
370
371         i = 2;
372         if (flags & TRANSPORT_PUSH_DRY_RUN)
373                 args[i++] = "--dry-run";
374         if (!(flags & TRANSPORT_PUSH_FORCE))
375                 args[i++] = "--ignore-existing";
376         args[i++] = temp_dir.buf;
377         args[i++] = rsync_url(transport->url);
378         args[i++] = NULL;
379         if (run_command(&rsync))
380                 result = error("Could not push to %s",
381                                 rsync_url(transport->url));
382
383         if (remove_dir_recursively(&temp_dir, 0))
384                 warning ("Could not remove temporary directory %s.",
385                                 temp_dir.buf);
386
387         strbuf_release(&buf);
388         strbuf_release(&temp_dir);
389
390         return result;
391 }
392
393 struct bundle_transport_data {
394         int fd;
395         struct bundle_header header;
396 };
397
398 static struct ref *get_refs_from_bundle(struct transport *transport, int for_push)
399 {
400         struct bundle_transport_data *data = transport->data;
401         struct ref *result = NULL;
402         int i;
403
404         if (for_push)
405                 return NULL;
406
407         if (data->fd > 0)
408                 close(data->fd);
409         data->fd = read_bundle_header(transport->url, &data->header);
410         if (data->fd < 0)
411                 die ("Could not read bundle '%s'.", transport->url);
412         for (i = 0; i < data->header.references.nr; i++) {
413                 struct ref_list_entry *e = data->header.references.list + i;
414                 struct ref *ref = alloc_ref(e->name);
415                 hashcpy(ref->old_sha1, e->sha1);
416                 ref->next = result;
417                 result = ref;
418         }
419         return result;
420 }
421
422 static int fetch_refs_from_bundle(struct transport *transport,
423                                int nr_heads, struct ref **to_fetch)
424 {
425         struct bundle_transport_data *data = transport->data;
426         return unbundle(&data->header, data->fd,
427                         transport->progress ? BUNDLE_VERBOSE : 0);
428 }
429
430 static int close_bundle(struct transport *transport)
431 {
432         struct bundle_transport_data *data = transport->data;
433         if (data->fd > 0)
434                 close(data->fd);
435         free(data);
436         return 0;
437 }
438
439 struct git_transport_data {
440         struct git_transport_options options;
441         struct child_process *conn;
442         int fd[2];
443         unsigned got_remote_heads : 1;
444         struct sha1_array extra_have;
445         struct sha1_array shallow;
446 };
447
448 static int set_git_option(struct git_transport_options *opts,
449                           const char *name, const char *value)
450 {
451         if (!strcmp(name, TRANS_OPT_UPLOADPACK)) {
452                 opts->uploadpack = value;
453                 return 0;
454         } else if (!strcmp(name, TRANS_OPT_RECEIVEPACK)) {
455                 opts->receivepack = value;
456                 return 0;
457         } else if (!strcmp(name, TRANS_OPT_THIN)) {
458                 opts->thin = !!value;
459                 return 0;
460         } else if (!strcmp(name, TRANS_OPT_FOLLOWTAGS)) {
461                 opts->followtags = !!value;
462                 return 0;
463         } else if (!strcmp(name, TRANS_OPT_KEEP)) {
464                 opts->keep = !!value;
465                 return 0;
466         } else if (!strcmp(name, TRANS_OPT_UPDATE_SHALLOW)) {
467                 opts->update_shallow = !!value;
468                 return 0;
469         } else if (!strcmp(name, TRANS_OPT_DEPTH)) {
470                 if (!value)
471                         opts->depth = 0;
472                 else {
473                         char *end;
474                         opts->depth = strtol(value, &end, 0);
475                         if (*end)
476                                 die("transport: invalid depth option '%s'", value);
477                 }
478                 return 0;
479         }
480         return 1;
481 }
482
483 static int connect_setup(struct transport *transport, int for_push, int verbose)
484 {
485         struct git_transport_data *data = transport->data;
486
487         if (data->conn)
488                 return 0;
489
490         data->conn = git_connect(data->fd, transport->url,
491                                  for_push ? data->options.receivepack :
492                                  data->options.uploadpack,
493                                  verbose ? CONNECT_VERBOSE : 0);
494
495         return 0;
496 }
497
498 static struct ref *get_refs_via_connect(struct transport *transport, int for_push)
499 {
500         struct git_transport_data *data = transport->data;
501         struct ref *refs;
502
503         connect_setup(transport, for_push, 0);
504         get_remote_heads(data->fd[0], NULL, 0, &refs,
505                          for_push ? REF_NORMAL : 0,
506                          &data->extra_have,
507                          &data->shallow);
508         data->got_remote_heads = 1;
509
510         return refs;
511 }
512
513 static int fetch_refs_via_pack(struct transport *transport,
514                                int nr_heads, struct ref **to_fetch)
515 {
516         struct git_transport_data *data = transport->data;
517         struct ref *refs;
518         char *dest = xstrdup(transport->url);
519         struct fetch_pack_args args;
520         struct ref *refs_tmp = NULL;
521
522         memset(&args, 0, sizeof(args));
523         args.uploadpack = data->options.uploadpack;
524         args.keep_pack = data->options.keep;
525         args.lock_pack = 1;
526         args.use_thin_pack = data->options.thin;
527         args.include_tag = data->options.followtags;
528         args.verbose = (transport->verbose > 1);
529         args.quiet = (transport->verbose < 0);
530         args.no_progress = !transport->progress;
531         args.depth = data->options.depth;
532         args.check_self_contained_and_connected =
533                 data->options.check_self_contained_and_connected;
534         args.cloning = transport->cloning;
535         args.update_shallow = data->options.update_shallow;
536
537         if (!data->got_remote_heads) {
538                 connect_setup(transport, 0, 0);
539                 get_remote_heads(data->fd[0], NULL, 0, &refs_tmp, 0,
540                                  NULL, &data->shallow);
541                 data->got_remote_heads = 1;
542         }
543
544         refs = fetch_pack(&args, data->fd, data->conn,
545                           refs_tmp ? refs_tmp : transport->remote_refs,
546                           dest, to_fetch, nr_heads, &data->shallow,
547                           &transport->pack_lockfile);
548         close(data->fd[0]);
549         close(data->fd[1]);
550         if (finish_connect(data->conn)) {
551                 free_refs(refs);
552                 refs = NULL;
553         }
554         data->conn = NULL;
555         data->got_remote_heads = 0;
556         data->options.self_contained_and_connected =
557                 args.self_contained_and_connected;
558
559         free_refs(refs_tmp);
560         free_refs(refs);
561         free(dest);
562         return (refs ? 0 : -1);
563 }
564
565 static int push_had_errors(struct ref *ref)
566 {
567         for (; ref; ref = ref->next) {
568                 switch (ref->status) {
569                 case REF_STATUS_NONE:
570                 case REF_STATUS_UPTODATE:
571                 case REF_STATUS_OK:
572                         break;
573                 default:
574                         return 1;
575                 }
576         }
577         return 0;
578 }
579
580 int transport_refs_pushed(struct ref *ref)
581 {
582         for (; ref; ref = ref->next) {
583                 switch(ref->status) {
584                 case REF_STATUS_NONE:
585                 case REF_STATUS_UPTODATE:
586                         break;
587                 default:
588                         return 1;
589                 }
590         }
591         return 0;
592 }
593
594 void transport_update_tracking_ref(struct remote *remote, struct ref *ref, int verbose)
595 {
596         struct refspec rs;
597
598         if (ref->status != REF_STATUS_OK && ref->status != REF_STATUS_UPTODATE)
599                 return;
600
601         rs.src = ref->name;
602         rs.dst = NULL;
603
604         if (!remote_find_tracking(remote, &rs)) {
605                 if (verbose)
606                         fprintf(stderr, "updating local tracking ref '%s'\n", rs.dst);
607                 if (ref->deletion) {
608                         delete_ref(rs.dst, NULL, 0);
609                 } else
610                         update_ref("update by push", rs.dst,
611                                         ref->new_sha1, NULL, 0, 0);
612                 free(rs.dst);
613         }
614 }
615
616 static void print_ref_status(char flag, const char *summary, struct ref *to, struct ref *from, const char *msg, int porcelain)
617 {
618         if (porcelain) {
619                 if (from)
620                         fprintf(stdout, "%c\t%s:%s\t", flag, from->name, to->name);
621                 else
622                         fprintf(stdout, "%c\t:%s\t", flag, to->name);
623                 if (msg)
624                         fprintf(stdout, "%s (%s)\n", summary, msg);
625                 else
626                         fprintf(stdout, "%s\n", summary);
627         } else {
628                 fprintf(stderr, " %c %-*s ", flag, TRANSPORT_SUMMARY_WIDTH, summary);
629                 if (from)
630                         fprintf(stderr, "%s -> %s", prettify_refname(from->name), prettify_refname(to->name));
631                 else
632                         fputs(prettify_refname(to->name), stderr);
633                 if (msg) {
634                         fputs(" (", stderr);
635                         fputs(msg, stderr);
636                         fputc(')', stderr);
637                 }
638                 fputc('\n', stderr);
639         }
640 }
641
642 static const char *status_abbrev(unsigned char sha1[20])
643 {
644         return find_unique_abbrev(sha1, DEFAULT_ABBREV);
645 }
646
647 static void print_ok_ref_status(struct ref *ref, int porcelain)
648 {
649         if (ref->deletion)
650                 print_ref_status('-', "[deleted]", ref, NULL, NULL, porcelain);
651         else if (is_null_sha1(ref->old_sha1))
652                 print_ref_status('*',
653                         (starts_with(ref->name, "refs/tags/") ? "[new tag]" :
654                         "[new branch]"),
655                         ref, ref->peer_ref, NULL, porcelain);
656         else {
657                 char quickref[84];
658                 char type;
659                 const char *msg;
660
661                 strcpy(quickref, status_abbrev(ref->old_sha1));
662                 if (ref->forced_update) {
663                         strcat(quickref, "...");
664                         type = '+';
665                         msg = "forced update";
666                 } else {
667                         strcat(quickref, "..");
668                         type = ' ';
669                         msg = NULL;
670                 }
671                 strcat(quickref, status_abbrev(ref->new_sha1));
672
673                 print_ref_status(type, quickref, ref, ref->peer_ref, msg, porcelain);
674         }
675 }
676
677 static int print_one_push_status(struct ref *ref, const char *dest, int count, int porcelain)
678 {
679         if (!count)
680                 fprintf(porcelain ? stdout : stderr, "To %s\n", dest);
681
682         switch(ref->status) {
683         case REF_STATUS_NONE:
684                 print_ref_status('X', "[no match]", ref, NULL, NULL, porcelain);
685                 break;
686         case REF_STATUS_REJECT_NODELETE:
687                 print_ref_status('!', "[rejected]", ref, NULL,
688                                                  "remote does not support deleting refs", porcelain);
689                 break;
690         case REF_STATUS_UPTODATE:
691                 print_ref_status('=', "[up to date]", ref,
692                                                  ref->peer_ref, NULL, porcelain);
693                 break;
694         case REF_STATUS_REJECT_NONFASTFORWARD:
695                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
696                                                  "non-fast-forward", porcelain);
697                 break;
698         case REF_STATUS_REJECT_ALREADY_EXISTS:
699                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
700                                                  "already exists", porcelain);
701                 break;
702         case REF_STATUS_REJECT_FETCH_FIRST:
703                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
704                                                  "fetch first", porcelain);
705                 break;
706         case REF_STATUS_REJECT_NEEDS_FORCE:
707                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
708                                                  "needs force", porcelain);
709                 break;
710         case REF_STATUS_REJECT_STALE:
711                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
712                                                  "stale info", porcelain);
713                 break;
714         case REF_STATUS_REJECT_SHALLOW:
715                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
716                                                  "new shallow roots not allowed", porcelain);
717                 break;
718         case REF_STATUS_REMOTE_REJECT:
719                 print_ref_status('!', "[remote rejected]", ref,
720                                                  ref->deletion ? NULL : ref->peer_ref,
721                                                  ref->remote_status, porcelain);
722                 break;
723         case REF_STATUS_EXPECTING_REPORT:
724                 print_ref_status('!', "[remote failure]", ref,
725                                                  ref->deletion ? NULL : ref->peer_ref,
726                                                  "remote failed to report status", porcelain);
727                 break;
728         case REF_STATUS_ATOMIC_PUSH_FAILED:
729                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
730                                                  "atomic push failed", porcelain);
731                 break;
732         case REF_STATUS_OK:
733                 print_ok_ref_status(ref, porcelain);
734                 break;
735         }
736
737         return 1;
738 }
739
740 void transport_print_push_status(const char *dest, struct ref *refs,
741                                   int verbose, int porcelain, unsigned int *reject_reasons)
742 {
743         struct ref *ref;
744         int n = 0;
745         unsigned char head_sha1[20];
746         char *head;
747
748         head = resolve_refdup("HEAD", RESOLVE_REF_READING, head_sha1, NULL);
749
750         if (verbose) {
751                 for (ref = refs; ref; ref = ref->next)
752                         if (ref->status == REF_STATUS_UPTODATE)
753                                 n += print_one_push_status(ref, dest, n, porcelain);
754         }
755
756         for (ref = refs; ref; ref = ref->next)
757                 if (ref->status == REF_STATUS_OK)
758                         n += print_one_push_status(ref, dest, n, porcelain);
759
760         *reject_reasons = 0;
761         for (ref = refs; ref; ref = ref->next) {
762                 if (ref->status != REF_STATUS_NONE &&
763                     ref->status != REF_STATUS_UPTODATE &&
764                     ref->status != REF_STATUS_OK)
765                         n += print_one_push_status(ref, dest, n, porcelain);
766                 if (ref->status == REF_STATUS_REJECT_NONFASTFORWARD) {
767                         if (head != NULL && !strcmp(head, ref->name))
768                                 *reject_reasons |= REJECT_NON_FF_HEAD;
769                         else
770                                 *reject_reasons |= REJECT_NON_FF_OTHER;
771                 } else if (ref->status == REF_STATUS_REJECT_ALREADY_EXISTS) {
772                         *reject_reasons |= REJECT_ALREADY_EXISTS;
773                 } else if (ref->status == REF_STATUS_REJECT_FETCH_FIRST) {
774                         *reject_reasons |= REJECT_FETCH_FIRST;
775                 } else if (ref->status == REF_STATUS_REJECT_NEEDS_FORCE) {
776                         *reject_reasons |= REJECT_NEEDS_FORCE;
777                 }
778         }
779         free(head);
780 }
781
782 void transport_verify_remote_names(int nr_heads, const char **heads)
783 {
784         int i;
785
786         for (i = 0; i < nr_heads; i++) {
787                 const char *local = heads[i];
788                 const char *remote = strrchr(heads[i], ':');
789
790                 if (*local == '+')
791                         local++;
792
793                 /* A matching refspec is okay.  */
794                 if (remote == local && remote[1] == '\0')
795                         continue;
796
797                 remote = remote ? (remote + 1) : local;
798                 if (check_refname_format(remote,
799                                 REFNAME_ALLOW_ONELEVEL|REFNAME_REFSPEC_PATTERN))
800                         die("remote part of refspec is not a valid name in %s",
801                                 heads[i]);
802         }
803 }
804
805 static int git_transport_push(struct transport *transport, struct ref *remote_refs, int flags)
806 {
807         struct git_transport_data *data = transport->data;
808         struct send_pack_args args;
809         int ret;
810
811         if (!data->got_remote_heads) {
812                 struct ref *tmp_refs;
813                 connect_setup(transport, 1, 0);
814
815                 get_remote_heads(data->fd[0], NULL, 0, &tmp_refs, REF_NORMAL,
816                                  NULL, &data->shallow);
817                 data->got_remote_heads = 1;
818         }
819
820         memset(&args, 0, sizeof(args));
821         args.send_mirror = !!(flags & TRANSPORT_PUSH_MIRROR);
822         args.force_update = !!(flags & TRANSPORT_PUSH_FORCE);
823         args.use_thin_pack = data->options.thin;
824         args.verbose = (transport->verbose > 0);
825         args.quiet = (transport->verbose < 0);
826         args.progress = transport->progress;
827         args.dry_run = !!(flags & TRANSPORT_PUSH_DRY_RUN);
828         args.porcelain = !!(flags & TRANSPORT_PUSH_PORCELAIN);
829         args.atomic = !!(flags & TRANSPORT_PUSH_ATOMIC);
830         args.url = transport->url;
831
832         if (flags & TRANSPORT_PUSH_CERT_ALWAYS)
833                 args.push_cert = SEND_PACK_PUSH_CERT_ALWAYS;
834         else if (flags & TRANSPORT_PUSH_CERT_IF_ASKED)
835                 args.push_cert = SEND_PACK_PUSH_CERT_IF_ASKED;
836         else
837                 args.push_cert = SEND_PACK_PUSH_CERT_NEVER;
838
839         ret = send_pack(&args, data->fd, data->conn, remote_refs,
840                         &data->extra_have);
841
842         close(data->fd[1]);
843         close(data->fd[0]);
844         ret |= finish_connect(data->conn);
845         data->conn = NULL;
846         data->got_remote_heads = 0;
847
848         return ret;
849 }
850
851 static int connect_git(struct transport *transport, const char *name,
852                        const char *executable, int fd[2])
853 {
854         struct git_transport_data *data = transport->data;
855         data->conn = git_connect(data->fd, transport->url,
856                                  executable, 0);
857         fd[0] = data->fd[0];
858         fd[1] = data->fd[1];
859         return 0;
860 }
861
862 static int disconnect_git(struct transport *transport)
863 {
864         struct git_transport_data *data = transport->data;
865         if (data->conn) {
866                 if (data->got_remote_heads)
867                         packet_flush(data->fd[1]);
868                 close(data->fd[0]);
869                 close(data->fd[1]);
870                 finish_connect(data->conn);
871         }
872
873         free(data);
874         return 0;
875 }
876
877 void transport_take_over(struct transport *transport,
878                          struct child_process *child)
879 {
880         struct git_transport_data *data;
881
882         if (!transport->smart_options)
883                 die("Bug detected: Taking over transport requires non-NULL "
884                     "smart_options field.");
885
886         data = xcalloc(1, sizeof(*data));
887         data->options = *transport->smart_options;
888         data->conn = child;
889         data->fd[0] = data->conn->out;
890         data->fd[1] = data->conn->in;
891         data->got_remote_heads = 0;
892         transport->data = data;
893
894         transport->set_option = NULL;
895         transport->get_refs_list = get_refs_via_connect;
896         transport->fetch = fetch_refs_via_pack;
897         transport->push = NULL;
898         transport->push_refs = git_transport_push;
899         transport->disconnect = disconnect_git;
900         transport->smart_options = &(data->options);
901
902         transport->cannot_reuse = 1;
903 }
904
905 static int is_file(const char *url)
906 {
907         struct stat buf;
908         if (stat(url, &buf))
909                 return 0;
910         return S_ISREG(buf.st_mode);
911 }
912
913 static int external_specification_len(const char *url)
914 {
915         return strchr(url, ':') - url;
916 }
917
918 static const struct string_list *protocol_whitelist(void)
919 {
920         static int enabled = -1;
921         static struct string_list allowed = STRING_LIST_INIT_DUP;
922
923         if (enabled < 0) {
924                 const char *v = getenv("GIT_ALLOW_PROTOCOL");
925                 if (v) {
926                         string_list_split(&allowed, v, ':', -1);
927                         string_list_sort(&allowed);
928                         enabled = 1;
929                 } else {
930                         enabled = 0;
931                 }
932         }
933
934         return enabled ? &allowed : NULL;
935 }
936
937 int is_transport_allowed(const char *type)
938 {
939         const struct string_list *allowed = protocol_whitelist();
940         return !allowed || string_list_has_string(allowed, type);
941 }
942
943 void transport_check_allowed(const char *type)
944 {
945         if (!is_transport_allowed(type))
946                 die("transport '%s' not allowed", type);
947 }
948
949 int transport_restrict_protocols(void)
950 {
951         return !!protocol_whitelist();
952 }
953
954 struct transport *transport_get(struct remote *remote, const char *url)
955 {
956         const char *helper;
957         struct transport *ret = xcalloc(1, sizeof(*ret));
958
959         ret->progress = isatty(2);
960
961         if (!remote)
962                 die("No remote provided to transport_get()");
963
964         ret->got_remote_refs = 0;
965         ret->remote = remote;
966         helper = remote->foreign_vcs;
967
968         if (!url && remote->url)
969                 url = remote->url[0];
970         ret->url = url;
971
972         /* maybe it is a foreign URL? */
973         if (url) {
974                 const char *p = url;
975
976                 while (is_urlschemechar(p == url, *p))
977                         p++;
978                 if (starts_with(p, "::"))
979                         helper = xstrndup(url, p - url);
980         }
981
982         if (helper) {
983                 transport_helper_init(ret, helper);
984         } else if (starts_with(url, "rsync:")) {
985                 transport_check_allowed("rsync");
986                 ret->get_refs_list = get_refs_via_rsync;
987                 ret->fetch = fetch_objs_via_rsync;
988                 ret->push = rsync_transport_push;
989                 ret->smart_options = NULL;
990         } else if (url_is_local_not_ssh(url) && is_file(url) && is_bundle(url, 1)) {
991                 struct bundle_transport_data *data = xcalloc(1, sizeof(*data));
992                 transport_check_allowed("file");
993                 ret->data = data;
994                 ret->get_refs_list = get_refs_from_bundle;
995                 ret->fetch = fetch_refs_from_bundle;
996                 ret->disconnect = close_bundle;
997                 ret->smart_options = NULL;
998         } else if (!is_url(url)
999                 || starts_with(url, "file://")
1000                 || starts_with(url, "git://")
1001                 || starts_with(url, "ssh://")
1002                 || starts_with(url, "git+ssh://")
1003                 || starts_with(url, "ssh+git://")) {
1004                 /*
1005                  * These are builtin smart transports; "allowed" transports
1006                  * will be checked individually in git_connect.
1007                  */
1008                 struct git_transport_data *data = xcalloc(1, sizeof(*data));
1009                 ret->data = data;
1010                 ret->set_option = NULL;
1011                 ret->get_refs_list = get_refs_via_connect;
1012                 ret->fetch = fetch_refs_via_pack;
1013                 ret->push_refs = git_transport_push;
1014                 ret->connect = connect_git;
1015                 ret->disconnect = disconnect_git;
1016                 ret->smart_options = &(data->options);
1017
1018                 data->conn = NULL;
1019                 data->got_remote_heads = 0;
1020         } else {
1021                 /* Unknown protocol in URL. Pass to external handler. */
1022                 int len = external_specification_len(url);
1023                 char *handler = xmemdupz(url, len);
1024                 transport_helper_init(ret, handler);
1025         }
1026
1027         if (ret->smart_options) {
1028                 ret->smart_options->thin = 1;
1029                 ret->smart_options->uploadpack = "git-upload-pack";
1030                 if (remote->uploadpack)
1031                         ret->smart_options->uploadpack = remote->uploadpack;
1032                 ret->smart_options->receivepack = "git-receive-pack";
1033                 if (remote->receivepack)
1034                         ret->smart_options->receivepack = remote->receivepack;
1035         }
1036
1037         return ret;
1038 }
1039
1040 int transport_set_option(struct transport *transport,
1041                          const char *name, const char *value)
1042 {
1043         int git_reports = 1, protocol_reports = 1;
1044
1045         if (transport->smart_options)
1046                 git_reports = set_git_option(transport->smart_options,
1047                                              name, value);
1048
1049         if (transport->set_option)
1050                 protocol_reports = transport->set_option(transport, name,
1051                                                         value);
1052
1053         /* If either report is 0, report 0 (success). */
1054         if (!git_reports || !protocol_reports)
1055                 return 0;
1056         /* If either reports -1 (invalid value), report -1. */
1057         if ((git_reports == -1) || (protocol_reports == -1))
1058                 return -1;
1059         /* Otherwise if both report unknown, report unknown. */
1060         return 1;
1061 }
1062
1063 void transport_set_verbosity(struct transport *transport, int verbosity,
1064         int force_progress)
1065 {
1066         if (verbosity >= 1)
1067                 transport->verbose = verbosity <= 3 ? verbosity : 3;
1068         if (verbosity < 0)
1069                 transport->verbose = -1;
1070
1071         /**
1072          * Rules used to determine whether to report progress (processing aborts
1073          * when a rule is satisfied):
1074          *
1075          *   . Report progress, if force_progress is 1 (ie. --progress).
1076          *   . Don't report progress, if force_progress is 0 (ie. --no-progress).
1077          *   . Don't report progress, if verbosity < 0 (ie. -q/--quiet ).
1078          *   . Report progress if isatty(2) is 1.
1079          **/
1080         if (force_progress >= 0)
1081                 transport->progress = !!force_progress;
1082         else
1083                 transport->progress = verbosity >= 0 && isatty(2);
1084 }
1085
1086 static void die_with_unpushed_submodules(struct string_list *needs_pushing)
1087 {
1088         int i;
1089
1090         fprintf(stderr, "The following submodule paths contain changes that can\n"
1091                         "not be found on any remote:\n");
1092         for (i = 0; i < needs_pushing->nr; i++)
1093                 printf("  %s\n", needs_pushing->items[i].string);
1094         fprintf(stderr, "\nPlease try\n\n"
1095                         "       git push --recurse-submodules=on-demand\n\n"
1096                         "or cd to the path and use\n\n"
1097                         "       git push\n\n"
1098                         "to push them to a remote.\n\n");
1099
1100         string_list_clear(needs_pushing, 0);
1101
1102         die("Aborting.");
1103 }
1104
1105 static int run_pre_push_hook(struct transport *transport,
1106                              struct ref *remote_refs)
1107 {
1108         int ret = 0, x;
1109         struct ref *r;
1110         struct child_process proc = CHILD_PROCESS_INIT;
1111         struct strbuf buf;
1112         const char *argv[4];
1113
1114         if (!(argv[0] = find_hook("pre-push")))
1115                 return 0;
1116
1117         argv[1] = transport->remote->name;
1118         argv[2] = transport->url;
1119         argv[3] = NULL;
1120
1121         proc.argv = argv;
1122         proc.in = -1;
1123
1124         if (start_command(&proc)) {
1125                 finish_command(&proc);
1126                 return -1;
1127         }
1128
1129         strbuf_init(&buf, 256);
1130
1131         for (r = remote_refs; r; r = r->next) {
1132                 if (!r->peer_ref) continue;
1133                 if (r->status == REF_STATUS_REJECT_NONFASTFORWARD) continue;
1134                 if (r->status == REF_STATUS_REJECT_STALE) continue;
1135                 if (r->status == REF_STATUS_UPTODATE) continue;
1136
1137                 strbuf_reset(&buf);
1138                 strbuf_addf( &buf, "%s %s %s %s\n",
1139                          r->peer_ref->name, sha1_to_hex(r->new_sha1),
1140                          r->name, sha1_to_hex(r->old_sha1));
1141
1142                 if (write_in_full(proc.in, buf.buf, buf.len) != buf.len) {
1143                         ret = -1;
1144                         break;
1145                 }
1146         }
1147
1148         strbuf_release(&buf);
1149
1150         x = close(proc.in);
1151         if (!ret)
1152                 ret = x;
1153
1154         x = finish_command(&proc);
1155         if (!ret)
1156                 ret = x;
1157
1158         return ret;
1159 }
1160
1161 int transport_push(struct transport *transport,
1162                    int refspec_nr, const char **refspec, int flags,
1163                    unsigned int *reject_reasons)
1164 {
1165         *reject_reasons = 0;
1166         transport_verify_remote_names(refspec_nr, refspec);
1167
1168         if (transport->push) {
1169                 /* Maybe FIXME. But no important transport uses this case. */
1170                 if (flags & TRANSPORT_PUSH_SET_UPSTREAM)
1171                         die("This transport does not support using --set-upstream");
1172
1173                 return transport->push(transport, refspec_nr, refspec, flags);
1174         } else if (transport->push_refs) {
1175                 struct ref *remote_refs;
1176                 struct ref *local_refs = get_local_heads();
1177                 int match_flags = MATCH_REFS_NONE;
1178                 int verbose = (transport->verbose > 0);
1179                 int quiet = (transport->verbose < 0);
1180                 int porcelain = flags & TRANSPORT_PUSH_PORCELAIN;
1181                 int pretend = flags & TRANSPORT_PUSH_DRY_RUN;
1182                 int push_ret, ret, err;
1183
1184                 if (check_push_refs(local_refs, refspec_nr, refspec) < 0)
1185                         return -1;
1186
1187                 remote_refs = transport->get_refs_list(transport, 1);
1188
1189                 if (flags & TRANSPORT_PUSH_ALL)
1190                         match_flags |= MATCH_REFS_ALL;
1191                 if (flags & TRANSPORT_PUSH_MIRROR)
1192                         match_flags |= MATCH_REFS_MIRROR;
1193                 if (flags & TRANSPORT_PUSH_PRUNE)
1194                         match_flags |= MATCH_REFS_PRUNE;
1195                 if (flags & TRANSPORT_PUSH_FOLLOW_TAGS)
1196                         match_flags |= MATCH_REFS_FOLLOW_TAGS;
1197
1198                 if (match_push_refs(local_refs, &remote_refs,
1199                                     refspec_nr, refspec, match_flags)) {
1200                         return -1;
1201                 }
1202
1203                 if (transport->smart_options &&
1204                     transport->smart_options->cas &&
1205                     !is_empty_cas(transport->smart_options->cas))
1206                         apply_push_cas(transport->smart_options->cas,
1207                                        transport->remote, remote_refs);
1208
1209                 set_ref_status_for_push(remote_refs,
1210                         flags & TRANSPORT_PUSH_MIRROR,
1211                         flags & TRANSPORT_PUSH_FORCE);
1212
1213                 if (!(flags & TRANSPORT_PUSH_NO_HOOK))
1214                         if (run_pre_push_hook(transport, remote_refs))
1215                                 return -1;
1216
1217                 if ((flags & TRANSPORT_RECURSE_SUBMODULES_ON_DEMAND) && !is_bare_repository()) {
1218                         struct ref *ref = remote_refs;
1219                         for (; ref; ref = ref->next)
1220                                 if (!is_null_sha1(ref->new_sha1) &&
1221                                     !push_unpushed_submodules(ref->new_sha1,
1222                                             transport->remote->name))
1223                                     die ("Failed to push all needed submodules!");
1224                 }
1225
1226                 if ((flags & (TRANSPORT_RECURSE_SUBMODULES_ON_DEMAND |
1227                               TRANSPORT_RECURSE_SUBMODULES_CHECK)) && !is_bare_repository()) {
1228                         struct ref *ref = remote_refs;
1229                         struct string_list needs_pushing = STRING_LIST_INIT_DUP;
1230
1231                         for (; ref; ref = ref->next)
1232                                 if (!is_null_sha1(ref->new_sha1) &&
1233                                     find_unpushed_submodules(ref->new_sha1,
1234                                             transport->remote->name, &needs_pushing))
1235                                         die_with_unpushed_submodules(&needs_pushing);
1236                 }
1237
1238                 push_ret = transport->push_refs(transport, remote_refs, flags);
1239                 err = push_had_errors(remote_refs);
1240                 ret = push_ret | err;
1241
1242                 if (!quiet || err)
1243                         transport_print_push_status(transport->url, remote_refs,
1244                                         verbose | porcelain, porcelain,
1245                                         reject_reasons);
1246
1247                 if (flags & TRANSPORT_PUSH_SET_UPSTREAM)
1248                         set_upstreams(transport, remote_refs, pretend);
1249
1250                 if (!(flags & TRANSPORT_PUSH_DRY_RUN)) {
1251                         struct ref *ref;
1252                         for (ref = remote_refs; ref; ref = ref->next)
1253                                 transport_update_tracking_ref(transport->remote, ref, verbose);
1254                 }
1255
1256                 if (porcelain && !push_ret)
1257                         puts("Done");
1258                 else if (!quiet && !ret && !transport_refs_pushed(remote_refs))
1259                         fprintf(stderr, "Everything up-to-date\n");
1260
1261                 return ret;
1262         }
1263         return 1;
1264 }
1265
1266 const struct ref *transport_get_remote_refs(struct transport *transport)
1267 {
1268         if (!transport->got_remote_refs) {
1269                 transport->remote_refs = transport->get_refs_list(transport, 0);
1270                 transport->got_remote_refs = 1;
1271         }
1272
1273         return transport->remote_refs;
1274 }
1275
1276 int transport_fetch_refs(struct transport *transport, struct ref *refs)
1277 {
1278         int rc;
1279         int nr_heads = 0, nr_alloc = 0, nr_refs = 0;
1280         struct ref **heads = NULL;
1281         struct ref *rm;
1282
1283         for (rm = refs; rm; rm = rm->next) {
1284                 nr_refs++;
1285                 if (rm->peer_ref &&
1286                     !is_null_sha1(rm->old_sha1) &&
1287                     !hashcmp(rm->peer_ref->old_sha1, rm->old_sha1))
1288                         continue;
1289                 ALLOC_GROW(heads, nr_heads + 1, nr_alloc);
1290                 heads[nr_heads++] = rm;
1291         }
1292
1293         if (!nr_heads) {
1294                 /*
1295                  * When deepening of a shallow repository is requested,
1296                  * then local and remote refs are likely to still be equal.
1297                  * Just feed them all to the fetch method in that case.
1298                  * This condition shouldn't be met in a non-deepening fetch
1299                  * (see builtin/fetch.c:quickfetch()).
1300                  */
1301                 heads = xmalloc(nr_refs * sizeof(*heads));
1302                 for (rm = refs; rm; rm = rm->next)
1303                         heads[nr_heads++] = rm;
1304         }
1305
1306         rc = transport->fetch(transport, nr_heads, heads);
1307
1308         free(heads);
1309         return rc;
1310 }
1311
1312 void transport_unlock_pack(struct transport *transport)
1313 {
1314         if (transport->pack_lockfile) {
1315                 unlink_or_warn(transport->pack_lockfile);
1316                 free(transport->pack_lockfile);
1317                 transport->pack_lockfile = NULL;
1318         }
1319 }
1320
1321 int transport_connect(struct transport *transport, const char *name,
1322                       const char *exec, int fd[2])
1323 {
1324         if (transport->connect)
1325                 return transport->connect(transport, name, exec, fd);
1326         else
1327                 die("Operation not supported by protocol");
1328 }
1329
1330 int transport_disconnect(struct transport *transport)
1331 {
1332         int ret = 0;
1333         if (transport->disconnect)
1334                 ret = transport->disconnect(transport);
1335         free(transport);
1336         return ret;
1337 }
1338
1339 /*
1340  * Strip username (and password) from a URL and return
1341  * it in a newly allocated string.
1342  */
1343 char *transport_anonymize_url(const char *url)
1344 {
1345         char *anon_url, *scheme_prefix, *anon_part;
1346         size_t anon_len, prefix_len = 0;
1347
1348         anon_part = strchr(url, '@');
1349         if (url_is_local_not_ssh(url) || !anon_part)
1350                 goto literal_copy;
1351
1352         anon_len = strlen(++anon_part);
1353         scheme_prefix = strstr(url, "://");
1354         if (!scheme_prefix) {
1355                 if (!strchr(anon_part, ':'))
1356                         /* cannot be "me@there:/path/name" */
1357                         goto literal_copy;
1358         } else {
1359                 const char *cp;
1360                 /* make sure scheme is reasonable */
1361                 for (cp = url; cp < scheme_prefix; cp++) {
1362                         switch (*cp) {
1363                                 /* RFC 1738 2.1 */
1364                         case '+': case '.': case '-':
1365                                 break; /* ok */
1366                         default:
1367                                 if (isalnum(*cp))
1368                                         break;
1369                                 /* it isn't */
1370                                 goto literal_copy;
1371                         }
1372                 }
1373                 /* @ past the first slash does not count */
1374                 cp = strchr(scheme_prefix + 3, '/');
1375                 if (cp && cp < anon_part)
1376                         goto literal_copy;
1377                 prefix_len = scheme_prefix - url + 3;
1378         }
1379         anon_url = xcalloc(1, 1 + prefix_len + anon_len);
1380         memcpy(anon_url, url, prefix_len);
1381         memcpy(anon_url + prefix_len, anon_part, anon_len);
1382         return anon_url;
1383 literal_copy:
1384         return xstrdup(url);
1385 }
1386
1387 struct alternate_refs_data {
1388         alternate_ref_fn *fn;
1389         void *data;
1390 };
1391
1392 static int refs_from_alternate_cb(struct alternate_object_database *e,
1393                                   void *data)
1394 {
1395         char *other;
1396         size_t len;
1397         struct remote *remote;
1398         struct transport *transport;
1399         const struct ref *extra;
1400         struct alternate_refs_data *cb = data;
1401
1402         e->name[-1] = '\0';
1403         other = xstrdup(real_path(e->base));
1404         e->name[-1] = '/';
1405         len = strlen(other);
1406
1407         while (other[len-1] == '/')
1408                 other[--len] = '\0';
1409         if (len < 8 || memcmp(other + len - 8, "/objects", 8))
1410                 goto out;
1411         /* Is this a git repository with refs? */
1412         memcpy(other + len - 8, "/refs", 6);
1413         if (!is_directory(other))
1414                 goto out;
1415         other[len - 8] = '\0';
1416         remote = remote_get(other);
1417         transport = transport_get(remote, other);
1418         for (extra = transport_get_remote_refs(transport);
1419              extra;
1420              extra = extra->next)
1421                 cb->fn(extra, cb->data);
1422         transport_disconnect(transport);
1423 out:
1424         free(other);
1425         return 0;
1426 }
1427
1428 void for_each_alternate_ref(alternate_ref_fn fn, void *data)
1429 {
1430         struct alternate_refs_data cb;
1431         cb.fn = fn;
1432         cb.data = data;
1433         foreach_alt_odb(refs_from_alternate_cb, &cb);
1434 }