Merge branch 'js/get-short-oid-drop-cache'
[git] / transport.c
1 #include "cache.h"
2 #include "config.h"
3 #include "transport.h"
4 #include "run-command.h"
5 #include "pkt-line.h"
6 #include "fetch-pack.h"
7 #include "remote.h"
8 #include "connect.h"
9 #include "send-pack.h"
10 #include "walker.h"
11 #include "bundle.h"
12 #include "dir.h"
13 #include "refs.h"
14 #include "refspec.h"
15 #include "branch.h"
16 #include "url.h"
17 #include "submodule.h"
18 #include "string-list.h"
19 #include "sha1-array.h"
20 #include "sigchain.h"
21 #include "transport-internal.h"
22 #include "protocol.h"
23 #include "object-store.h"
24 #include "color.h"
25
26 static int transport_use_color = -1;
27 static char transport_colors[][COLOR_MAXLEN] = {
28         GIT_COLOR_RESET,
29         GIT_COLOR_RED           /* REJECTED */
30 };
31
32 enum color_transport {
33         TRANSPORT_COLOR_RESET = 0,
34         TRANSPORT_COLOR_REJECTED = 1
35 };
36
37 static int transport_color_config(void)
38 {
39         const char *keys[] = {
40                 "color.transport.reset",
41                 "color.transport.rejected"
42         }, *key = "color.transport";
43         char *value;
44         int i;
45         static int initialized;
46
47         if (initialized)
48                 return 0;
49         initialized = 1;
50
51         if (!git_config_get_string(key, &value))
52                 transport_use_color = git_config_colorbool(key, value);
53
54         if (!want_color_stderr(transport_use_color))
55                 return 0;
56
57         for (i = 0; i < ARRAY_SIZE(keys); i++)
58                 if (!git_config_get_string(keys[i], &value)) {
59                         if (!value)
60                                 return config_error_nonbool(keys[i]);
61                         if (color_parse(value, transport_colors[i]) < 0)
62                                 return -1;
63                 }
64
65         return 0;
66 }
67
68 static const char *transport_get_color(enum color_transport ix)
69 {
70         if (want_color_stderr(transport_use_color))
71                 return transport_colors[ix];
72         return "";
73 }
74
75 static void set_upstreams(struct transport *transport, struct ref *refs,
76         int pretend)
77 {
78         struct ref *ref;
79         for (ref = refs; ref; ref = ref->next) {
80                 const char *localname;
81                 const char *tmp;
82                 const char *remotename;
83                 int flag = 0;
84                 /*
85                  * Check suitability for tracking. Must be successful /
86                  * already up-to-date ref create/modify (not delete).
87                  */
88                 if (ref->status != REF_STATUS_OK &&
89                         ref->status != REF_STATUS_UPTODATE)
90                         continue;
91                 if (!ref->peer_ref)
92                         continue;
93                 if (is_null_oid(&ref->new_oid))
94                         continue;
95
96                 /* Follow symbolic refs (mainly for HEAD). */
97                 localname = ref->peer_ref->name;
98                 remotename = ref->name;
99                 tmp = resolve_ref_unsafe(localname, RESOLVE_REF_READING,
100                                          NULL, &flag);
101                 if (tmp && flag & REF_ISSYMREF &&
102                         starts_with(tmp, "refs/heads/"))
103                         localname = tmp;
104
105                 /* Both source and destination must be local branches. */
106                 if (!localname || !starts_with(localname, "refs/heads/"))
107                         continue;
108                 if (!remotename || !starts_with(remotename, "refs/heads/"))
109                         continue;
110
111                 if (!pretend)
112                         install_branch_config(BRANCH_CONFIG_VERBOSE,
113                                 localname + 11, transport->remote->name,
114                                 remotename);
115                 else
116                         printf(_("Would set upstream of '%s' to '%s' of '%s'\n"),
117                                 localname + 11, remotename + 11,
118                                 transport->remote->name);
119         }
120 }
121
122 struct bundle_transport_data {
123         int fd;
124         struct bundle_header header;
125 };
126
127 static struct ref *get_refs_from_bundle(struct transport *transport,
128                                         int for_push,
129                                         const struct argv_array *ref_prefixes)
130 {
131         struct bundle_transport_data *data = transport->data;
132         struct ref *result = NULL;
133         int i;
134
135         if (for_push)
136                 return NULL;
137
138         if (data->fd > 0)
139                 close(data->fd);
140         data->fd = read_bundle_header(transport->url, &data->header);
141         if (data->fd < 0)
142                 die(_("could not read bundle '%s'"), transport->url);
143         for (i = 0; i < data->header.references.nr; i++) {
144                 struct ref_list_entry *e = data->header.references.list + i;
145                 struct ref *ref = alloc_ref(e->name);
146                 oidcpy(&ref->old_oid, &e->oid);
147                 ref->next = result;
148                 result = ref;
149         }
150         return result;
151 }
152
153 static int fetch_refs_from_bundle(struct transport *transport,
154                                int nr_heads, struct ref **to_fetch)
155 {
156         struct bundle_transport_data *data = transport->data;
157         return unbundle(the_repository, &data->header, data->fd,
158                         transport->progress ? BUNDLE_VERBOSE : 0);
159 }
160
161 static int close_bundle(struct transport *transport)
162 {
163         struct bundle_transport_data *data = transport->data;
164         if (data->fd > 0)
165                 close(data->fd);
166         free(data);
167         return 0;
168 }
169
170 struct git_transport_data {
171         struct git_transport_options options;
172         struct child_process *conn;
173         int fd[2];
174         unsigned got_remote_heads : 1;
175         enum protocol_version version;
176         struct oid_array extra_have;
177         struct oid_array shallow;
178 };
179
180 static int set_git_option(struct git_transport_options *opts,
181                           const char *name, const char *value)
182 {
183         if (!strcmp(name, TRANS_OPT_UPLOADPACK)) {
184                 opts->uploadpack = value;
185                 return 0;
186         } else if (!strcmp(name, TRANS_OPT_RECEIVEPACK)) {
187                 opts->receivepack = value;
188                 return 0;
189         } else if (!strcmp(name, TRANS_OPT_THIN)) {
190                 opts->thin = !!value;
191                 return 0;
192         } else if (!strcmp(name, TRANS_OPT_FOLLOWTAGS)) {
193                 opts->followtags = !!value;
194                 return 0;
195         } else if (!strcmp(name, TRANS_OPT_KEEP)) {
196                 opts->keep = !!value;
197                 return 0;
198         } else if (!strcmp(name, TRANS_OPT_UPDATE_SHALLOW)) {
199                 opts->update_shallow = !!value;
200                 return 0;
201         } else if (!strcmp(name, TRANS_OPT_DEPTH)) {
202                 if (!value)
203                         opts->depth = 0;
204                 else {
205                         char *end;
206                         opts->depth = strtol(value, &end, 0);
207                         if (*end)
208                                 die(_("transport: invalid depth option '%s'"), value);
209                 }
210                 return 0;
211         } else if (!strcmp(name, TRANS_OPT_DEEPEN_SINCE)) {
212                 opts->deepen_since = value;
213                 return 0;
214         } else if (!strcmp(name, TRANS_OPT_DEEPEN_NOT)) {
215                 opts->deepen_not = (const struct string_list *)value;
216                 return 0;
217         } else if (!strcmp(name, TRANS_OPT_DEEPEN_RELATIVE)) {
218                 opts->deepen_relative = !!value;
219                 return 0;
220         } else if (!strcmp(name, TRANS_OPT_FROM_PROMISOR)) {
221                 opts->from_promisor = !!value;
222                 return 0;
223         } else if (!strcmp(name, TRANS_OPT_NO_DEPENDENTS)) {
224                 opts->no_dependents = !!value;
225                 return 0;
226         } else if (!strcmp(name, TRANS_OPT_LIST_OBJECTS_FILTER)) {
227                 parse_list_objects_filter(&opts->filter_options, value);
228                 return 0;
229         }
230         return 1;
231 }
232
233 static int connect_setup(struct transport *transport, int for_push)
234 {
235         struct git_transport_data *data = transport->data;
236         int flags = transport->verbose > 0 ? CONNECT_VERBOSE : 0;
237
238         if (data->conn)
239                 return 0;
240
241         switch (transport->family) {
242         case TRANSPORT_FAMILY_ALL: break;
243         case TRANSPORT_FAMILY_IPV4: flags |= CONNECT_IPV4; break;
244         case TRANSPORT_FAMILY_IPV6: flags |= CONNECT_IPV6; break;
245         }
246
247         data->conn = git_connect(data->fd, transport->url,
248                                  for_push ? data->options.receivepack :
249                                  data->options.uploadpack,
250                                  flags);
251
252         return 0;
253 }
254
255 /*
256  * Obtains the protocol version from the transport and writes it to
257  * transport->data->version, first connecting if not already connected.
258  *
259  * If the protocol version is one that allows skipping the listing of remote
260  * refs, and must_list_refs is 0, the listing of remote refs is skipped and
261  * this function returns NULL. Otherwise, this function returns the list of
262  * remote refs.
263  */
264 static struct ref *handshake(struct transport *transport, int for_push,
265                              const struct argv_array *ref_prefixes,
266                              int must_list_refs)
267 {
268         struct git_transport_data *data = transport->data;
269         struct ref *refs = NULL;
270         struct packet_reader reader;
271
272         connect_setup(transport, for_push);
273
274         packet_reader_init(&reader, data->fd[0], NULL, 0,
275                            PACKET_READ_CHOMP_NEWLINE |
276                            PACKET_READ_GENTLE_ON_EOF |
277                            PACKET_READ_DIE_ON_ERR_PACKET);
278
279         data->version = discover_version(&reader);
280         switch (data->version) {
281         case protocol_v2:
282                 if (must_list_refs)
283                         get_remote_refs(data->fd[1], &reader, &refs, for_push,
284                                         ref_prefixes,
285                                         transport->server_options);
286                 break;
287         case protocol_v1:
288         case protocol_v0:
289                 get_remote_heads(&reader, &refs,
290                                  for_push ? REF_NORMAL : 0,
291                                  &data->extra_have,
292                                  &data->shallow);
293                 break;
294         case protocol_unknown_version:
295                 BUG("unknown protocol version");
296         }
297         data->got_remote_heads = 1;
298
299         if (reader.line_peeked)
300                 BUG("buffer must be empty at the end of handshake()");
301
302         return refs;
303 }
304
305 static struct ref *get_refs_via_connect(struct transport *transport, int for_push,
306                                         const struct argv_array *ref_prefixes)
307 {
308         return handshake(transport, for_push, ref_prefixes, 1);
309 }
310
311 static int fetch_refs_via_pack(struct transport *transport,
312                                int nr_heads, struct ref **to_fetch)
313 {
314         int ret = 0;
315         struct git_transport_data *data = transport->data;
316         struct ref *refs = NULL;
317         char *dest = xstrdup(transport->url);
318         struct fetch_pack_args args;
319         struct ref *refs_tmp = NULL;
320
321         memset(&args, 0, sizeof(args));
322         args.uploadpack = data->options.uploadpack;
323         args.keep_pack = data->options.keep;
324         args.lock_pack = 1;
325         args.use_thin_pack = data->options.thin;
326         args.include_tag = data->options.followtags;
327         args.verbose = (transport->verbose > 1);
328         args.quiet = (transport->verbose < 0);
329         args.no_progress = !transport->progress;
330         args.depth = data->options.depth;
331         args.deepen_since = data->options.deepen_since;
332         args.deepen_not = data->options.deepen_not;
333         args.deepen_relative = data->options.deepen_relative;
334         args.check_self_contained_and_connected =
335                 data->options.check_self_contained_and_connected;
336         args.cloning = transport->cloning;
337         args.update_shallow = data->options.update_shallow;
338         args.from_promisor = data->options.from_promisor;
339         args.no_dependents = data->options.no_dependents;
340         args.filter_options = data->options.filter_options;
341         args.stateless_rpc = transport->stateless_rpc;
342         args.server_options = transport->server_options;
343         args.negotiation_tips = data->options.negotiation_tips;
344
345         if (!data->got_remote_heads) {
346                 int i;
347                 int must_list_refs = 0;
348                 for (i = 0; i < nr_heads; i++) {
349                         if (!to_fetch[i]->exact_oid) {
350                                 must_list_refs = 1;
351                                 break;
352                         }
353                 }
354                 refs_tmp = handshake(transport, 0, NULL, must_list_refs);
355         }
356
357         switch (data->version) {
358         case protocol_v2:
359                 refs = fetch_pack(&args, data->fd, data->conn,
360                                   refs_tmp ? refs_tmp : transport->remote_refs,
361                                   dest, to_fetch, nr_heads, &data->shallow,
362                                   &transport->pack_lockfile, data->version);
363                 break;
364         case protocol_v1:
365         case protocol_v0:
366                 refs = fetch_pack(&args, data->fd, data->conn,
367                                   refs_tmp ? refs_tmp : transport->remote_refs,
368                                   dest, to_fetch, nr_heads, &data->shallow,
369                                   &transport->pack_lockfile, data->version);
370                 break;
371         case protocol_unknown_version:
372                 BUG("unknown protocol version");
373         }
374
375         close(data->fd[0]);
376         close(data->fd[1]);
377         if (finish_connect(data->conn))
378                 ret = -1;
379         data->conn = NULL;
380         data->got_remote_heads = 0;
381         data->options.self_contained_and_connected =
382                 args.self_contained_and_connected;
383         data->options.connectivity_checked = args.connectivity_checked;
384
385         if (refs == NULL)
386                 ret = -1;
387         if (report_unmatched_refs(to_fetch, nr_heads))
388                 ret = -1;
389
390         free_refs(refs_tmp);
391         free_refs(refs);
392         free(dest);
393         return ret;
394 }
395
396 static int push_had_errors(struct ref *ref)
397 {
398         for (; ref; ref = ref->next) {
399                 switch (ref->status) {
400                 case REF_STATUS_NONE:
401                 case REF_STATUS_UPTODATE:
402                 case REF_STATUS_OK:
403                         break;
404                 default:
405                         return 1;
406                 }
407         }
408         return 0;
409 }
410
411 int transport_refs_pushed(struct ref *ref)
412 {
413         for (; ref; ref = ref->next) {
414                 switch(ref->status) {
415                 case REF_STATUS_NONE:
416                 case REF_STATUS_UPTODATE:
417                         break;
418                 default:
419                         return 1;
420                 }
421         }
422         return 0;
423 }
424
425 void transport_update_tracking_ref(struct remote *remote, struct ref *ref, int verbose)
426 {
427         struct refspec_item rs;
428
429         if (ref->status != REF_STATUS_OK && ref->status != REF_STATUS_UPTODATE)
430                 return;
431
432         rs.src = ref->name;
433         rs.dst = NULL;
434
435         if (!remote_find_tracking(remote, &rs)) {
436                 if (verbose)
437                         fprintf(stderr, "updating local tracking ref '%s'\n", rs.dst);
438                 if (ref->deletion) {
439                         delete_ref(NULL, rs.dst, NULL, 0);
440                 } else
441                         update_ref("update by push", rs.dst, &ref->new_oid,
442                                    NULL, 0, 0);
443                 free(rs.dst);
444         }
445 }
446
447 static void print_ref_status(char flag, const char *summary,
448                              struct ref *to, struct ref *from, const char *msg,
449                              int porcelain, int summary_width)
450 {
451         if (porcelain) {
452                 if (from)
453                         fprintf(stdout, "%c\t%s:%s\t", flag, from->name, to->name);
454                 else
455                         fprintf(stdout, "%c\t:%s\t", flag, to->name);
456                 if (msg)
457                         fprintf(stdout, "%s (%s)\n", summary, msg);
458                 else
459                         fprintf(stdout, "%s\n", summary);
460         } else {
461                 const char *red = "", *reset = "";
462                 if (push_had_errors(to)) {
463                         red = transport_get_color(TRANSPORT_COLOR_REJECTED);
464                         reset = transport_get_color(TRANSPORT_COLOR_RESET);
465                 }
466                 fprintf(stderr, " %s%c %-*s%s ", red, flag, summary_width,
467                         summary, reset);
468                 if (from)
469                         fprintf(stderr, "%s -> %s", prettify_refname(from->name), prettify_refname(to->name));
470                 else
471                         fputs(prettify_refname(to->name), stderr);
472                 if (msg) {
473                         fputs(" (", stderr);
474                         fputs(msg, stderr);
475                         fputc(')', stderr);
476                 }
477                 fputc('\n', stderr);
478         }
479 }
480
481 static void print_ok_ref_status(struct ref *ref, int porcelain, int summary_width)
482 {
483         if (ref->deletion)
484                 print_ref_status('-', "[deleted]", ref, NULL, NULL,
485                                  porcelain, summary_width);
486         else if (is_null_oid(&ref->old_oid))
487                 print_ref_status('*',
488                         (starts_with(ref->name, "refs/tags/") ? "[new tag]" :
489                         "[new branch]"),
490                         ref, ref->peer_ref, NULL, porcelain, summary_width);
491         else {
492                 struct strbuf quickref = STRBUF_INIT;
493                 char type;
494                 const char *msg;
495
496                 strbuf_add_unique_abbrev(&quickref, &ref->old_oid,
497                                          DEFAULT_ABBREV);
498                 if (ref->forced_update) {
499                         strbuf_addstr(&quickref, "...");
500                         type = '+';
501                         msg = "forced update";
502                 } else {
503                         strbuf_addstr(&quickref, "..");
504                         type = ' ';
505                         msg = NULL;
506                 }
507                 strbuf_add_unique_abbrev(&quickref, &ref->new_oid,
508                                          DEFAULT_ABBREV);
509
510                 print_ref_status(type, quickref.buf, ref, ref->peer_ref, msg,
511                                  porcelain, summary_width);
512                 strbuf_release(&quickref);
513         }
514 }
515
516 static int print_one_push_status(struct ref *ref, const char *dest, int count,
517                                  int porcelain, int summary_width)
518 {
519         if (!count) {
520                 char *url = transport_anonymize_url(dest);
521                 fprintf(porcelain ? stdout : stderr, "To %s\n", url);
522                 free(url);
523         }
524
525         switch(ref->status) {
526         case REF_STATUS_NONE:
527                 print_ref_status('X', "[no match]", ref, NULL, NULL,
528                                  porcelain, summary_width);
529                 break;
530         case REF_STATUS_REJECT_NODELETE:
531                 print_ref_status('!', "[rejected]", ref, NULL,
532                                  "remote does not support deleting refs",
533                                  porcelain, summary_width);
534                 break;
535         case REF_STATUS_UPTODATE:
536                 print_ref_status('=', "[up to date]", ref,
537                                  ref->peer_ref, NULL, porcelain, summary_width);
538                 break;
539         case REF_STATUS_REJECT_NONFASTFORWARD:
540                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
541                                  "non-fast-forward", porcelain, summary_width);
542                 break;
543         case REF_STATUS_REJECT_ALREADY_EXISTS:
544                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
545                                  "already exists", porcelain, summary_width);
546                 break;
547         case REF_STATUS_REJECT_FETCH_FIRST:
548                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
549                                  "fetch first", porcelain, summary_width);
550                 break;
551         case REF_STATUS_REJECT_NEEDS_FORCE:
552                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
553                                  "needs force", porcelain, summary_width);
554                 break;
555         case REF_STATUS_REJECT_STALE:
556                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
557                                  "stale info", porcelain, summary_width);
558                 break;
559         case REF_STATUS_REJECT_SHALLOW:
560                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
561                                  "new shallow roots not allowed",
562                                  porcelain, summary_width);
563                 break;
564         case REF_STATUS_REMOTE_REJECT:
565                 print_ref_status('!', "[remote rejected]", ref,
566                                  ref->deletion ? NULL : ref->peer_ref,
567                                  ref->remote_status, porcelain, summary_width);
568                 break;
569         case REF_STATUS_EXPECTING_REPORT:
570                 print_ref_status('!', "[remote failure]", ref,
571                                  ref->deletion ? NULL : ref->peer_ref,
572                                  "remote failed to report status",
573                                  porcelain, summary_width);
574                 break;
575         case REF_STATUS_ATOMIC_PUSH_FAILED:
576                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
577                                  "atomic push failed", porcelain, summary_width);
578                 break;
579         case REF_STATUS_OK:
580                 print_ok_ref_status(ref, porcelain, summary_width);
581                 break;
582         }
583
584         return 1;
585 }
586
587 static int measure_abbrev(const struct object_id *oid, int sofar)
588 {
589         char hex[GIT_MAX_HEXSZ + 1];
590         int w = find_unique_abbrev_r(hex, oid, DEFAULT_ABBREV);
591
592         return (w < sofar) ? sofar : w;
593 }
594
595 int transport_summary_width(const struct ref *refs)
596 {
597         int maxw = -1;
598
599         for (; refs; refs = refs->next) {
600                 maxw = measure_abbrev(&refs->old_oid, maxw);
601                 maxw = measure_abbrev(&refs->new_oid, maxw);
602         }
603         if (maxw < 0)
604                 maxw = FALLBACK_DEFAULT_ABBREV;
605         return (2 * maxw + 3);
606 }
607
608 void transport_print_push_status(const char *dest, struct ref *refs,
609                                   int verbose, int porcelain, unsigned int *reject_reasons)
610 {
611         struct ref *ref;
612         int n = 0;
613         char *head;
614         int summary_width = transport_summary_width(refs);
615
616         if (transport_color_config() < 0)
617                 warning(_("could not parse transport.color.* config"));
618
619         head = resolve_refdup("HEAD", RESOLVE_REF_READING, NULL, NULL);
620
621         if (verbose) {
622                 for (ref = refs; ref; ref = ref->next)
623                         if (ref->status == REF_STATUS_UPTODATE)
624                                 n += print_one_push_status(ref, dest, n,
625                                                            porcelain, summary_width);
626         }
627
628         for (ref = refs; ref; ref = ref->next)
629                 if (ref->status == REF_STATUS_OK)
630                         n += print_one_push_status(ref, dest, n,
631                                                    porcelain, summary_width);
632
633         *reject_reasons = 0;
634         for (ref = refs; ref; ref = ref->next) {
635                 if (ref->status != REF_STATUS_NONE &&
636                     ref->status != REF_STATUS_UPTODATE &&
637                     ref->status != REF_STATUS_OK)
638                         n += print_one_push_status(ref, dest, n,
639                                                    porcelain, summary_width);
640                 if (ref->status == REF_STATUS_REJECT_NONFASTFORWARD) {
641                         if (head != NULL && !strcmp(head, ref->name))
642                                 *reject_reasons |= REJECT_NON_FF_HEAD;
643                         else
644                                 *reject_reasons |= REJECT_NON_FF_OTHER;
645                 } else if (ref->status == REF_STATUS_REJECT_ALREADY_EXISTS) {
646                         *reject_reasons |= REJECT_ALREADY_EXISTS;
647                 } else if (ref->status == REF_STATUS_REJECT_FETCH_FIRST) {
648                         *reject_reasons |= REJECT_FETCH_FIRST;
649                 } else if (ref->status == REF_STATUS_REJECT_NEEDS_FORCE) {
650                         *reject_reasons |= REJECT_NEEDS_FORCE;
651                 }
652         }
653         free(head);
654 }
655
656 static int git_transport_push(struct transport *transport, struct ref *remote_refs, int flags)
657 {
658         struct git_transport_data *data = transport->data;
659         struct send_pack_args args;
660         int ret = 0;
661
662         if (transport_color_config() < 0)
663                 return -1;
664
665         if (!data->got_remote_heads)
666                 get_refs_via_connect(transport, 1, NULL);
667
668         memset(&args, 0, sizeof(args));
669         args.send_mirror = !!(flags & TRANSPORT_PUSH_MIRROR);
670         args.force_update = !!(flags & TRANSPORT_PUSH_FORCE);
671         args.use_thin_pack = data->options.thin;
672         args.verbose = (transport->verbose > 0);
673         args.quiet = (transport->verbose < 0);
674         args.progress = transport->progress;
675         args.dry_run = !!(flags & TRANSPORT_PUSH_DRY_RUN);
676         args.porcelain = !!(flags & TRANSPORT_PUSH_PORCELAIN);
677         args.atomic = !!(flags & TRANSPORT_PUSH_ATOMIC);
678         args.push_options = transport->push_options;
679         args.url = transport->url;
680
681         if (flags & TRANSPORT_PUSH_CERT_ALWAYS)
682                 args.push_cert = SEND_PACK_PUSH_CERT_ALWAYS;
683         else if (flags & TRANSPORT_PUSH_CERT_IF_ASKED)
684                 args.push_cert = SEND_PACK_PUSH_CERT_IF_ASKED;
685         else
686                 args.push_cert = SEND_PACK_PUSH_CERT_NEVER;
687
688         switch (data->version) {
689         case protocol_v2:
690                 die(_("support for protocol v2 not implemented yet"));
691                 break;
692         case protocol_v1:
693         case protocol_v0:
694                 ret = send_pack(&args, data->fd, data->conn, remote_refs,
695                                 &data->extra_have);
696                 break;
697         case protocol_unknown_version:
698                 BUG("unknown protocol version");
699         }
700
701         close(data->fd[1]);
702         close(data->fd[0]);
703         ret |= finish_connect(data->conn);
704         data->conn = NULL;
705         data->got_remote_heads = 0;
706
707         return ret;
708 }
709
710 static int connect_git(struct transport *transport, const char *name,
711                        const char *executable, int fd[2])
712 {
713         struct git_transport_data *data = transport->data;
714         data->conn = git_connect(data->fd, transport->url,
715                                  executable, 0);
716         fd[0] = data->fd[0];
717         fd[1] = data->fd[1];
718         return 0;
719 }
720
721 static int disconnect_git(struct transport *transport)
722 {
723         struct git_transport_data *data = transport->data;
724         if (data->conn) {
725                 if (data->got_remote_heads)
726                         packet_flush(data->fd[1]);
727                 close(data->fd[0]);
728                 close(data->fd[1]);
729                 finish_connect(data->conn);
730         }
731
732         free(data);
733         return 0;
734 }
735
736 static struct transport_vtable taken_over_vtable = {
737         1,
738         NULL,
739         get_refs_via_connect,
740         fetch_refs_via_pack,
741         git_transport_push,
742         NULL,
743         disconnect_git
744 };
745
746 void transport_take_over(struct transport *transport,
747                          struct child_process *child)
748 {
749         struct git_transport_data *data;
750
751         if (!transport->smart_options)
752                 BUG("taking over transport requires non-NULL "
753                     "smart_options field.");
754
755         data = xcalloc(1, sizeof(*data));
756         data->options = *transport->smart_options;
757         data->conn = child;
758         data->fd[0] = data->conn->out;
759         data->fd[1] = data->conn->in;
760         data->got_remote_heads = 0;
761         transport->data = data;
762
763         transport->vtable = &taken_over_vtable;
764         transport->smart_options = &(data->options);
765
766         transport->cannot_reuse = 1;
767 }
768
769 static int is_file(const char *url)
770 {
771         struct stat buf;
772         if (stat(url, &buf))
773                 return 0;
774         return S_ISREG(buf.st_mode);
775 }
776
777 static int external_specification_len(const char *url)
778 {
779         return strchr(url, ':') - url;
780 }
781
782 static const struct string_list *protocol_whitelist(void)
783 {
784         static int enabled = -1;
785         static struct string_list allowed = STRING_LIST_INIT_DUP;
786
787         if (enabled < 0) {
788                 const char *v = getenv("GIT_ALLOW_PROTOCOL");
789                 if (v) {
790                         string_list_split(&allowed, v, ':', -1);
791                         string_list_sort(&allowed);
792                         enabled = 1;
793                 } else {
794                         enabled = 0;
795                 }
796         }
797
798         return enabled ? &allowed : NULL;
799 }
800
801 enum protocol_allow_config {
802         PROTOCOL_ALLOW_NEVER = 0,
803         PROTOCOL_ALLOW_USER_ONLY,
804         PROTOCOL_ALLOW_ALWAYS
805 };
806
807 static enum protocol_allow_config parse_protocol_config(const char *key,
808                                                         const char *value)
809 {
810         if (!strcasecmp(value, "always"))
811                 return PROTOCOL_ALLOW_ALWAYS;
812         else if (!strcasecmp(value, "never"))
813                 return PROTOCOL_ALLOW_NEVER;
814         else if (!strcasecmp(value, "user"))
815                 return PROTOCOL_ALLOW_USER_ONLY;
816
817         die(_("unknown value for config '%s': %s"), key, value);
818 }
819
820 static enum protocol_allow_config get_protocol_config(const char *type)
821 {
822         char *key = xstrfmt("protocol.%s.allow", type);
823         char *value;
824
825         /* first check the per-protocol config */
826         if (!git_config_get_string(key, &value)) {
827                 enum protocol_allow_config ret =
828                         parse_protocol_config(key, value);
829                 free(key);
830                 free(value);
831                 return ret;
832         }
833         free(key);
834
835         /* if defined, fallback to user-defined default for unknown protocols */
836         if (!git_config_get_string("protocol.allow", &value)) {
837                 enum protocol_allow_config ret =
838                         parse_protocol_config("protocol.allow", value);
839                 free(value);
840                 return ret;
841         }
842
843         /* fallback to built-in defaults */
844         /* known safe */
845         if (!strcmp(type, "http") ||
846             !strcmp(type, "https") ||
847             !strcmp(type, "git") ||
848             !strcmp(type, "ssh") ||
849             !strcmp(type, "file"))
850                 return PROTOCOL_ALLOW_ALWAYS;
851
852         /* known scary; err on the side of caution */
853         if (!strcmp(type, "ext"))
854                 return PROTOCOL_ALLOW_NEVER;
855
856         /* unknown; by default let them be used only directly by the user */
857         return PROTOCOL_ALLOW_USER_ONLY;
858 }
859
860 int is_transport_allowed(const char *type, int from_user)
861 {
862         const struct string_list *whitelist = protocol_whitelist();
863         if (whitelist)
864                 return string_list_has_string(whitelist, type);
865
866         switch (get_protocol_config(type)) {
867         case PROTOCOL_ALLOW_ALWAYS:
868                 return 1;
869         case PROTOCOL_ALLOW_NEVER:
870                 return 0;
871         case PROTOCOL_ALLOW_USER_ONLY:
872                 if (from_user < 0)
873                         from_user = git_env_bool("GIT_PROTOCOL_FROM_USER", 1);
874                 return from_user;
875         }
876
877         BUG("invalid protocol_allow_config type");
878 }
879
880 void transport_check_allowed(const char *type)
881 {
882         if (!is_transport_allowed(type, -1))
883                 die(_("transport '%s' not allowed"), type);
884 }
885
886 static struct transport_vtable bundle_vtable = {
887         0,
888         NULL,
889         get_refs_from_bundle,
890         fetch_refs_from_bundle,
891         NULL,
892         NULL,
893         close_bundle
894 };
895
896 static struct transport_vtable builtin_smart_vtable = {
897         1,
898         NULL,
899         get_refs_via_connect,
900         fetch_refs_via_pack,
901         git_transport_push,
902         connect_git,
903         disconnect_git
904 };
905
906 struct transport *transport_get(struct remote *remote, const char *url)
907 {
908         const char *helper;
909         struct transport *ret = xcalloc(1, sizeof(*ret));
910
911         ret->progress = isatty(2);
912
913         if (!remote)
914                 BUG("No remote provided to transport_get()");
915
916         ret->got_remote_refs = 0;
917         ret->remote = remote;
918         helper = remote->foreign_vcs;
919
920         if (!url && remote->url)
921                 url = remote->url[0];
922         ret->url = url;
923
924         /* maybe it is a foreign URL? */
925         if (url) {
926                 const char *p = url;
927
928                 while (is_urlschemechar(p == url, *p))
929                         p++;
930                 if (starts_with(p, "::"))
931                         helper = xstrndup(url, p - url);
932         }
933
934         if (helper) {
935                 transport_helper_init(ret, helper);
936         } else if (starts_with(url, "rsync:")) {
937                 die(_("git-over-rsync is no longer supported"));
938         } else if (url_is_local_not_ssh(url) && is_file(url) && is_bundle(url, 1)) {
939                 struct bundle_transport_data *data = xcalloc(1, sizeof(*data));
940                 transport_check_allowed("file");
941                 ret->data = data;
942                 ret->vtable = &bundle_vtable;
943                 ret->smart_options = NULL;
944         } else if (!is_url(url)
945                 || starts_with(url, "file://")
946                 || starts_with(url, "git://")
947                 || starts_with(url, "ssh://")
948                 || starts_with(url, "git+ssh://") /* deprecated - do not use */
949                 || starts_with(url, "ssh+git://") /* deprecated - do not use */
950                 ) {
951                 /*
952                  * These are builtin smart transports; "allowed" transports
953                  * will be checked individually in git_connect.
954                  */
955                 struct git_transport_data *data = xcalloc(1, sizeof(*data));
956                 ret->data = data;
957                 ret->vtable = &builtin_smart_vtable;
958                 ret->smart_options = &(data->options);
959
960                 data->conn = NULL;
961                 data->got_remote_heads = 0;
962         } else {
963                 /* Unknown protocol in URL. Pass to external handler. */
964                 int len = external_specification_len(url);
965                 char *handler = xmemdupz(url, len);
966                 transport_helper_init(ret, handler);
967         }
968
969         if (ret->smart_options) {
970                 ret->smart_options->thin = 1;
971                 ret->smart_options->uploadpack = "git-upload-pack";
972                 if (remote->uploadpack)
973                         ret->smart_options->uploadpack = remote->uploadpack;
974                 ret->smart_options->receivepack = "git-receive-pack";
975                 if (remote->receivepack)
976                         ret->smart_options->receivepack = remote->receivepack;
977         }
978
979         return ret;
980 }
981
982 int transport_set_option(struct transport *transport,
983                          const char *name, const char *value)
984 {
985         int git_reports = 1, protocol_reports = 1;
986
987         if (transport->smart_options)
988                 git_reports = set_git_option(transport->smart_options,
989                                              name, value);
990
991         if (transport->vtable->set_option)
992                 protocol_reports = transport->vtable->set_option(transport,
993                                                                  name, value);
994
995         /* If either report is 0, report 0 (success). */
996         if (!git_reports || !protocol_reports)
997                 return 0;
998         /* If either reports -1 (invalid value), report -1. */
999         if ((git_reports == -1) || (protocol_reports == -1))
1000                 return -1;
1001         /* Otherwise if both report unknown, report unknown. */
1002         return 1;
1003 }
1004
1005 void transport_set_verbosity(struct transport *transport, int verbosity,
1006         int force_progress)
1007 {
1008         if (verbosity >= 1)
1009                 transport->verbose = verbosity <= 3 ? verbosity : 3;
1010         if (verbosity < 0)
1011                 transport->verbose = -1;
1012
1013         /**
1014          * Rules used to determine whether to report progress (processing aborts
1015          * when a rule is satisfied):
1016          *
1017          *   . Report progress, if force_progress is 1 (ie. --progress).
1018          *   . Don't report progress, if force_progress is 0 (ie. --no-progress).
1019          *   . Don't report progress, if verbosity < 0 (ie. -q/--quiet ).
1020          *   . Report progress if isatty(2) is 1.
1021          **/
1022         if (force_progress >= 0)
1023                 transport->progress = !!force_progress;
1024         else
1025                 transport->progress = verbosity >= 0 && isatty(2);
1026 }
1027
1028 static void die_with_unpushed_submodules(struct string_list *needs_pushing)
1029 {
1030         int i;
1031
1032         fprintf(stderr, _("The following submodule paths contain changes that can\n"
1033                         "not be found on any remote:\n"));
1034         for (i = 0; i < needs_pushing->nr; i++)
1035                 fprintf(stderr, "  %s\n", needs_pushing->items[i].string);
1036         fprintf(stderr, _("\nPlease try\n\n"
1037                           "     git push --recurse-submodules=on-demand\n\n"
1038                           "or cd to the path and use\n\n"
1039                           "     git push\n\n"
1040                           "to push them to a remote.\n\n"));
1041
1042         string_list_clear(needs_pushing, 0);
1043
1044         die(_("Aborting."));
1045 }
1046
1047 static int run_pre_push_hook(struct transport *transport,
1048                              struct ref *remote_refs)
1049 {
1050         int ret = 0, x;
1051         struct ref *r;
1052         struct child_process proc = CHILD_PROCESS_INIT;
1053         struct strbuf buf;
1054         const char *argv[4];
1055
1056         if (!(argv[0] = find_hook("pre-push")))
1057                 return 0;
1058
1059         argv[1] = transport->remote->name;
1060         argv[2] = transport->url;
1061         argv[3] = NULL;
1062
1063         proc.argv = argv;
1064         proc.in = -1;
1065         proc.trace2_hook_name = "pre-push";
1066
1067         if (start_command(&proc)) {
1068                 finish_command(&proc);
1069                 return -1;
1070         }
1071
1072         sigchain_push(SIGPIPE, SIG_IGN);
1073
1074         strbuf_init(&buf, 256);
1075
1076         for (r = remote_refs; r; r = r->next) {
1077                 if (!r->peer_ref) continue;
1078                 if (r->status == REF_STATUS_REJECT_NONFASTFORWARD) continue;
1079                 if (r->status == REF_STATUS_REJECT_STALE) continue;
1080                 if (r->status == REF_STATUS_UPTODATE) continue;
1081
1082                 strbuf_reset(&buf);
1083                 strbuf_addf( &buf, "%s %s %s %s\n",
1084                          r->peer_ref->name, oid_to_hex(&r->new_oid),
1085                          r->name, oid_to_hex(&r->old_oid));
1086
1087                 if (write_in_full(proc.in, buf.buf, buf.len) < 0) {
1088                         /* We do not mind if a hook does not read all refs. */
1089                         if (errno != EPIPE)
1090                                 ret = -1;
1091                         break;
1092                 }
1093         }
1094
1095         strbuf_release(&buf);
1096
1097         x = close(proc.in);
1098         if (!ret)
1099                 ret = x;
1100
1101         sigchain_pop(SIGPIPE);
1102
1103         x = finish_command(&proc);
1104         if (!ret)
1105                 ret = x;
1106
1107         return ret;
1108 }
1109
1110 int transport_push(struct repository *r,
1111                    struct transport *transport,
1112                    struct refspec *rs, int flags,
1113                    unsigned int *reject_reasons)
1114 {
1115         *reject_reasons = 0;
1116
1117         if (transport_color_config() < 0)
1118                 return -1;
1119
1120         if (transport->vtable->push_refs) {
1121                 struct ref *remote_refs;
1122                 struct ref *local_refs = get_local_heads();
1123                 int match_flags = MATCH_REFS_NONE;
1124                 int verbose = (transport->verbose > 0);
1125                 int quiet = (transport->verbose < 0);
1126                 int porcelain = flags & TRANSPORT_PUSH_PORCELAIN;
1127                 int pretend = flags & TRANSPORT_PUSH_DRY_RUN;
1128                 int push_ret, ret, err;
1129                 struct argv_array ref_prefixes = ARGV_ARRAY_INIT;
1130
1131                 if (check_push_refs(local_refs, rs) < 0)
1132                         return -1;
1133
1134                 refspec_ref_prefixes(rs, &ref_prefixes);
1135
1136                 remote_refs = transport->vtable->get_refs_list(transport, 1,
1137                                                                &ref_prefixes);
1138
1139                 argv_array_clear(&ref_prefixes);
1140
1141                 if (flags & TRANSPORT_PUSH_ALL)
1142                         match_flags |= MATCH_REFS_ALL;
1143                 if (flags & TRANSPORT_PUSH_MIRROR)
1144                         match_flags |= MATCH_REFS_MIRROR;
1145                 if (flags & TRANSPORT_PUSH_PRUNE)
1146                         match_flags |= MATCH_REFS_PRUNE;
1147                 if (flags & TRANSPORT_PUSH_FOLLOW_TAGS)
1148                         match_flags |= MATCH_REFS_FOLLOW_TAGS;
1149
1150                 if (match_push_refs(local_refs, &remote_refs, rs, match_flags))
1151                         return -1;
1152
1153                 if (transport->smart_options &&
1154                     transport->smart_options->cas &&
1155                     !is_empty_cas(transport->smart_options->cas))
1156                         apply_push_cas(transport->smart_options->cas,
1157                                        transport->remote, remote_refs);
1158
1159                 set_ref_status_for_push(remote_refs,
1160                         flags & TRANSPORT_PUSH_MIRROR,
1161                         flags & TRANSPORT_PUSH_FORCE);
1162
1163                 if (!(flags & TRANSPORT_PUSH_NO_HOOK))
1164                         if (run_pre_push_hook(transport, remote_refs))
1165                                 return -1;
1166
1167                 if ((flags & (TRANSPORT_RECURSE_SUBMODULES_ON_DEMAND |
1168                               TRANSPORT_RECURSE_SUBMODULES_ONLY)) &&
1169                     !is_bare_repository()) {
1170                         struct ref *ref = remote_refs;
1171                         struct oid_array commits = OID_ARRAY_INIT;
1172
1173                         for (; ref; ref = ref->next)
1174                                 if (!is_null_oid(&ref->new_oid))
1175                                         oid_array_append(&commits,
1176                                                           &ref->new_oid);
1177
1178                         if (!push_unpushed_submodules(r,
1179                                                       &commits,
1180                                                       transport->remote,
1181                                                       rs,
1182                                                       transport->push_options,
1183                                                       pretend)) {
1184                                 oid_array_clear(&commits);
1185                                 die(_("failed to push all needed submodules"));
1186                         }
1187                         oid_array_clear(&commits);
1188                 }
1189
1190                 if (((flags & TRANSPORT_RECURSE_SUBMODULES_CHECK) ||
1191                      ((flags & (TRANSPORT_RECURSE_SUBMODULES_ON_DEMAND |
1192                                 TRANSPORT_RECURSE_SUBMODULES_ONLY)) &&
1193                       !pretend)) && !is_bare_repository()) {
1194                         struct ref *ref = remote_refs;
1195                         struct string_list needs_pushing = STRING_LIST_INIT_DUP;
1196                         struct oid_array commits = OID_ARRAY_INIT;
1197
1198                         for (; ref; ref = ref->next)
1199                                 if (!is_null_oid(&ref->new_oid))
1200                                         oid_array_append(&commits,
1201                                                           &ref->new_oid);
1202
1203                         if (find_unpushed_submodules(r,
1204                                                      &commits,
1205                                                      transport->remote->name,
1206                                                      &needs_pushing)) {
1207                                 oid_array_clear(&commits);
1208                                 die_with_unpushed_submodules(&needs_pushing);
1209                         }
1210                         string_list_clear(&needs_pushing, 0);
1211                         oid_array_clear(&commits);
1212                 }
1213
1214                 if (!(flags & TRANSPORT_RECURSE_SUBMODULES_ONLY))
1215                         push_ret = transport->vtable->push_refs(transport, remote_refs, flags);
1216                 else
1217                         push_ret = 0;
1218                 err = push_had_errors(remote_refs);
1219                 ret = push_ret | err;
1220
1221                 if (!quiet || err)
1222                         transport_print_push_status(transport->url, remote_refs,
1223                                         verbose | porcelain, porcelain,
1224                                         reject_reasons);
1225
1226                 if (flags & TRANSPORT_PUSH_SET_UPSTREAM)
1227                         set_upstreams(transport, remote_refs, pretend);
1228
1229                 if (!(flags & (TRANSPORT_PUSH_DRY_RUN |
1230                                TRANSPORT_RECURSE_SUBMODULES_ONLY))) {
1231                         struct ref *ref;
1232                         for (ref = remote_refs; ref; ref = ref->next)
1233                                 transport_update_tracking_ref(transport->remote, ref, verbose);
1234                 }
1235
1236                 if (porcelain && !push_ret)
1237                         puts("Done");
1238                 else if (!quiet && !ret && !transport_refs_pushed(remote_refs))
1239                         fprintf(stderr, "Everything up-to-date\n");
1240
1241                 return ret;
1242         }
1243         return 1;
1244 }
1245
1246 const struct ref *transport_get_remote_refs(struct transport *transport,
1247                                             const struct argv_array *ref_prefixes)
1248 {
1249         if (!transport->got_remote_refs) {
1250                 transport->remote_refs =
1251                         transport->vtable->get_refs_list(transport, 0,
1252                                                          ref_prefixes);
1253                 transport->got_remote_refs = 1;
1254         }
1255
1256         return transport->remote_refs;
1257 }
1258
1259 int transport_fetch_refs(struct transport *transport, struct ref *refs)
1260 {
1261         int rc;
1262         int nr_heads = 0, nr_alloc = 0, nr_refs = 0;
1263         struct ref **heads = NULL;
1264         struct ref *rm;
1265
1266         if (!transport->vtable->fetch_without_list)
1267                 /*
1268                  * Some transports (e.g. the built-in bundle transport and the
1269                  * transport helper interface) do not work when fetching is
1270                  * done immediately after transport creation. List the remote
1271                  * refs anyway (if not already listed) as a workaround.
1272                  */
1273                 transport_get_remote_refs(transport, NULL);
1274
1275         for (rm = refs; rm; rm = rm->next) {
1276                 nr_refs++;
1277                 if (rm->peer_ref &&
1278                     !is_null_oid(&rm->old_oid) &&
1279                     oideq(&rm->peer_ref->old_oid, &rm->old_oid))
1280                         continue;
1281                 ALLOC_GROW(heads, nr_heads + 1, nr_alloc);
1282                 heads[nr_heads++] = rm;
1283         }
1284
1285         if (!nr_heads) {
1286                 /*
1287                  * When deepening of a shallow repository is requested,
1288                  * then local and remote refs are likely to still be equal.
1289                  * Just feed them all to the fetch method in that case.
1290                  * This condition shouldn't be met in a non-deepening fetch
1291                  * (see builtin/fetch.c:quickfetch()).
1292                  */
1293                 ALLOC_ARRAY(heads, nr_refs);
1294                 for (rm = refs; rm; rm = rm->next)
1295                         heads[nr_heads++] = rm;
1296         }
1297
1298         rc = transport->vtable->fetch(transport, nr_heads, heads);
1299
1300         free(heads);
1301         return rc;
1302 }
1303
1304 void transport_unlock_pack(struct transport *transport)
1305 {
1306         if (transport->pack_lockfile) {
1307                 unlink_or_warn(transport->pack_lockfile);
1308                 FREE_AND_NULL(transport->pack_lockfile);
1309         }
1310 }
1311
1312 int transport_connect(struct transport *transport, const char *name,
1313                       const char *exec, int fd[2])
1314 {
1315         if (transport->vtable->connect)
1316                 return transport->vtable->connect(transport, name, exec, fd);
1317         else
1318                 die(_("operation not supported by protocol"));
1319 }
1320
1321 int transport_disconnect(struct transport *transport)
1322 {
1323         int ret = 0;
1324         if (transport->vtable->disconnect)
1325                 ret = transport->vtable->disconnect(transport);
1326         free(transport);
1327         return ret;
1328 }
1329
1330 /*
1331  * Strip username (and password) from a URL and return
1332  * it in a newly allocated string.
1333  */
1334 char *transport_anonymize_url(const char *url)
1335 {
1336         char *scheme_prefix, *anon_part;
1337         size_t anon_len, prefix_len = 0;
1338
1339         anon_part = strchr(url, '@');
1340         if (url_is_local_not_ssh(url) || !anon_part)
1341                 goto literal_copy;
1342
1343         anon_len = strlen(++anon_part);
1344         scheme_prefix = strstr(url, "://");
1345         if (!scheme_prefix) {
1346                 if (!strchr(anon_part, ':'))
1347                         /* cannot be "me@there:/path/name" */
1348                         goto literal_copy;
1349         } else {
1350                 const char *cp;
1351                 /* make sure scheme is reasonable */
1352                 for (cp = url; cp < scheme_prefix; cp++) {
1353                         switch (*cp) {
1354                                 /* RFC 1738 2.1 */
1355                         case '+': case '.': case '-':
1356                                 break; /* ok */
1357                         default:
1358                                 if (isalnum(*cp))
1359                                         break;
1360                                 /* it isn't */
1361                                 goto literal_copy;
1362                         }
1363                 }
1364                 /* @ past the first slash does not count */
1365                 cp = strchr(scheme_prefix + 3, '/');
1366                 if (cp && cp < anon_part)
1367                         goto literal_copy;
1368                 prefix_len = scheme_prefix - url + 3;
1369         }
1370         return xstrfmt("%.*s%.*s", (int)prefix_len, url,
1371                        (int)anon_len, anon_part);
1372 literal_copy:
1373         return xstrdup(url);
1374 }
1375
1376 static void fill_alternate_refs_command(struct child_process *cmd,
1377                                         const char *repo_path)
1378 {
1379         const char *value;
1380
1381         if (!git_config_get_value("core.alternateRefsCommand", &value)) {
1382                 cmd->use_shell = 1;
1383
1384                 argv_array_push(&cmd->args, value);
1385                 argv_array_push(&cmd->args, repo_path);
1386         } else {
1387                 cmd->git_cmd = 1;
1388
1389                 argv_array_pushf(&cmd->args, "--git-dir=%s", repo_path);
1390                 argv_array_push(&cmd->args, "for-each-ref");
1391                 argv_array_push(&cmd->args, "--format=%(objectname)");
1392
1393                 if (!git_config_get_value("core.alternateRefsPrefixes", &value)) {
1394                         argv_array_push(&cmd->args, "--");
1395                         argv_array_split(&cmd->args, value);
1396                 }
1397         }
1398
1399         cmd->env = local_repo_env;
1400         cmd->out = -1;
1401 }
1402
1403 static void read_alternate_refs(const char *path,
1404                                 alternate_ref_fn *cb,
1405                                 void *data)
1406 {
1407         struct child_process cmd = CHILD_PROCESS_INIT;
1408         struct strbuf line = STRBUF_INIT;
1409         FILE *fh;
1410
1411         fill_alternate_refs_command(&cmd, path);
1412
1413         if (start_command(&cmd))
1414                 return;
1415
1416         fh = xfdopen(cmd.out, "r");
1417         while (strbuf_getline_lf(&line, fh) != EOF) {
1418                 struct object_id oid;
1419                 const char *p;
1420
1421                 if (parse_oid_hex(line.buf, &oid, &p) || *p) {
1422                         warning(_("invalid line while parsing alternate refs: %s"),
1423                                 line.buf);
1424                         break;
1425                 }
1426
1427                 cb(&oid, data);
1428         }
1429
1430         fclose(fh);
1431         finish_command(&cmd);
1432 }
1433
1434 struct alternate_refs_data {
1435         alternate_ref_fn *fn;
1436         void *data;
1437 };
1438
1439 static int refs_from_alternate_cb(struct object_directory *e,
1440                                   void *data)
1441 {
1442         struct strbuf path = STRBUF_INIT;
1443         size_t base_len;
1444         struct alternate_refs_data *cb = data;
1445
1446         if (!strbuf_realpath(&path, e->path, 0))
1447                 goto out;
1448         if (!strbuf_strip_suffix(&path, "/objects"))
1449                 goto out;
1450         base_len = path.len;
1451
1452         /* Is this a git repository with refs? */
1453         strbuf_addstr(&path, "/refs");
1454         if (!is_directory(path.buf))
1455                 goto out;
1456         strbuf_setlen(&path, base_len);
1457
1458         read_alternate_refs(path.buf, cb->fn, cb->data);
1459
1460 out:
1461         strbuf_release(&path);
1462         return 0;
1463 }
1464
1465 void for_each_alternate_ref(alternate_ref_fn fn, void *data)
1466 {
1467         struct alternate_refs_data cb;
1468         cb.fn = fn;
1469         cb.data = data;
1470         foreach_alt_odb(refs_from_alternate_cb, &cb);
1471 }