Merge branch 'bb/redecl-enum-fix'
[git] / transport-helper.c
1 #include "cache.h"
2 #include "transport.h"
3 #include "quote.h"
4 #include "run-command.h"
5 #include "commit.h"
6 #include "diff.h"
7 #include "revision.h"
8 #include "remote.h"
9 #include "string-list.h"
10 #include "thread-utils.h"
11 #include "sigchain.h"
12 #include "argv-array.h"
13 #include "refs.h"
14 #include "refspec.h"
15 #include "transport-internal.h"
16 #include "protocol.h"
17
18 static int debug;
19
20 struct helper_data {
21         const char *name;
22         struct child_process *helper;
23         FILE *out;
24         unsigned fetch : 1,
25                 import : 1,
26                 bidi_import : 1,
27                 export : 1,
28                 option : 1,
29                 push : 1,
30                 connect : 1,
31                 stateless_connect : 1,
32                 signed_tags : 1,
33                 check_connectivity : 1,
34                 no_disconnect_req : 1,
35                 no_private_update : 1;
36         char *export_marks;
37         char *import_marks;
38         /* These go from remote name (as in "list") to private name */
39         struct refspec rs;
40         /* Transport options for fetch-pack/send-pack (should one of
41          * those be invoked).
42          */
43         struct git_transport_options transport_options;
44 };
45
46 static void sendline(struct helper_data *helper, struct strbuf *buffer)
47 {
48         if (debug)
49                 fprintf(stderr, "Debug: Remote helper: -> %s", buffer->buf);
50         if (write_in_full(helper->helper->in, buffer->buf, buffer->len) < 0)
51                 die_errno(_("full write to remote helper failed"));
52 }
53
54 static int recvline_fh(FILE *helper, struct strbuf *buffer)
55 {
56         strbuf_reset(buffer);
57         if (debug)
58                 fprintf(stderr, "Debug: Remote helper: Waiting...\n");
59         if (strbuf_getline(buffer, helper) == EOF) {
60                 if (debug)
61                         fprintf(stderr, "Debug: Remote helper quit.\n");
62                 return 1;
63         }
64
65         if (debug)
66                 fprintf(stderr, "Debug: Remote helper: <- %s\n", buffer->buf);
67         return 0;
68 }
69
70 static int recvline(struct helper_data *helper, struct strbuf *buffer)
71 {
72         return recvline_fh(helper->out, buffer);
73 }
74
75 static void write_constant(int fd, const char *str)
76 {
77         if (debug)
78                 fprintf(stderr, "Debug: Remote helper: -> %s", str);
79         if (write_in_full(fd, str, strlen(str)) < 0)
80                 die_errno(_("full write to remote helper failed"));
81 }
82
83 static const char *remove_ext_force(const char *url)
84 {
85         if (url) {
86                 const char *colon = strchr(url, ':');
87                 if (colon && colon[1] == ':')
88                         return colon + 2;
89         }
90         return url;
91 }
92
93 static void do_take_over(struct transport *transport)
94 {
95         struct helper_data *data;
96         data = (struct helper_data *)transport->data;
97         transport_take_over(transport, data->helper);
98         fclose(data->out);
99         free(data);
100 }
101
102 static void standard_options(struct transport *t);
103
104 static struct child_process *get_helper(struct transport *transport)
105 {
106         struct helper_data *data = transport->data;
107         struct strbuf buf = STRBUF_INIT;
108         struct child_process *helper;
109         int duped;
110         int code;
111
112         if (data->helper)
113                 return data->helper;
114
115         helper = xmalloc(sizeof(*helper));
116         child_process_init(helper);
117         helper->in = -1;
118         helper->out = -1;
119         helper->err = 0;
120         argv_array_pushf(&helper->args, "git-remote-%s", data->name);
121         argv_array_push(&helper->args, transport->remote->name);
122         argv_array_push(&helper->args, remove_ext_force(transport->url));
123         helper->git_cmd = 0;
124         helper->silent_exec_failure = 1;
125
126         if (have_git_dir())
127                 argv_array_pushf(&helper->env_array, "%s=%s",
128                                  GIT_DIR_ENVIRONMENT, get_git_dir());
129
130         code = start_command(helper);
131         if (code < 0 && errno == ENOENT)
132                 die(_("unable to find remote helper for '%s'"), data->name);
133         else if (code != 0)
134                 exit(code);
135
136         data->helper = helper;
137         data->no_disconnect_req = 0;
138         refspec_init(&data->rs, REFSPEC_FETCH);
139
140         /*
141          * Open the output as FILE* so strbuf_getline_*() family of
142          * functions can be used.
143          * Do this with duped fd because fclose() will close the fd,
144          * and stuff like taking over will require the fd to remain.
145          */
146         duped = dup(helper->out);
147         if (duped < 0)
148                 die_errno(_("can't dup helper output fd"));
149         data->out = xfdopen(duped, "r");
150
151         write_constant(helper->in, "capabilities\n");
152
153         while (1) {
154                 const char *capname, *arg;
155                 int mandatory = 0;
156                 if (recvline(data, &buf))
157                         exit(128);
158
159                 if (!*buf.buf)
160                         break;
161
162                 if (*buf.buf == '*') {
163                         capname = buf.buf + 1;
164                         mandatory = 1;
165                 } else
166                         capname = buf.buf;
167
168                 if (debug)
169                         fprintf(stderr, "Debug: Got cap %s\n", capname);
170                 if (!strcmp(capname, "fetch"))
171                         data->fetch = 1;
172                 else if (!strcmp(capname, "option"))
173                         data->option = 1;
174                 else if (!strcmp(capname, "push"))
175                         data->push = 1;
176                 else if (!strcmp(capname, "import"))
177                         data->import = 1;
178                 else if (!strcmp(capname, "bidi-import"))
179                         data->bidi_import = 1;
180                 else if (!strcmp(capname, "export"))
181                         data->export = 1;
182                 else if (!strcmp(capname, "check-connectivity"))
183                         data->check_connectivity = 1;
184                 else if (skip_prefix(capname, "refspec ", &arg)) {
185                         refspec_append(&data->rs, arg);
186                 } else if (!strcmp(capname, "connect")) {
187                         data->connect = 1;
188                 } else if (!strcmp(capname, "stateless-connect")) {
189                         data->stateless_connect = 1;
190                 } else if (!strcmp(capname, "signed-tags")) {
191                         data->signed_tags = 1;
192                 } else if (skip_prefix(capname, "export-marks ", &arg)) {
193                         data->export_marks = xstrdup(arg);
194                 } else if (skip_prefix(capname, "import-marks ", &arg)) {
195                         data->import_marks = xstrdup(arg);
196                 } else if (starts_with(capname, "no-private-update")) {
197                         data->no_private_update = 1;
198                 } else if (mandatory) {
199                         die(_("unknown mandatory capability %s; this remote "
200                               "helper probably needs newer version of Git"),
201                             capname);
202                 }
203         }
204         if (!data->rs.nr && (data->import || data->bidi_import || data->export)) {
205                 warning(_("this remote helper should implement refspec capability"));
206         }
207         strbuf_release(&buf);
208         if (debug)
209                 fprintf(stderr, "Debug: Capabilities complete.\n");
210         standard_options(transport);
211         return data->helper;
212 }
213
214 static int disconnect_helper(struct transport *transport)
215 {
216         struct helper_data *data = transport->data;
217         int res = 0;
218
219         if (data->helper) {
220                 if (debug)
221                         fprintf(stderr, "Debug: Disconnecting.\n");
222                 if (!data->no_disconnect_req) {
223                         /*
224                          * Ignore write errors; there's nothing we can do,
225                          * since we're about to close the pipe anyway. And the
226                          * most likely error is EPIPE due to the helper dying
227                          * to report an error itself.
228                          */
229                         sigchain_push(SIGPIPE, SIG_IGN);
230                         xwrite(data->helper->in, "\n", 1);
231                         sigchain_pop(SIGPIPE);
232                 }
233                 close(data->helper->in);
234                 close(data->helper->out);
235                 fclose(data->out);
236                 res = finish_command(data->helper);
237                 FREE_AND_NULL(data->helper);
238         }
239         return res;
240 }
241
242 static const char *unsupported_options[] = {
243         TRANS_OPT_UPLOADPACK,
244         TRANS_OPT_RECEIVEPACK,
245         TRANS_OPT_THIN,
246         TRANS_OPT_KEEP
247         };
248
249 static const char *boolean_options[] = {
250         TRANS_OPT_THIN,
251         TRANS_OPT_KEEP,
252         TRANS_OPT_FOLLOWTAGS,
253         TRANS_OPT_DEEPEN_RELATIVE
254         };
255
256 static int strbuf_set_helper_option(struct helper_data *data,
257                                     struct strbuf *buf)
258 {
259         int ret;
260
261         sendline(data, buf);
262         if (recvline(data, buf))
263                 exit(128);
264
265         if (!strcmp(buf->buf, "ok"))
266                 ret = 0;
267         else if (starts_with(buf->buf, "error"))
268                 ret = -1;
269         else if (!strcmp(buf->buf, "unsupported"))
270                 ret = 1;
271         else {
272                 warning(_("%s unexpectedly said: '%s'"), data->name, buf->buf);
273                 ret = 1;
274         }
275         return ret;
276 }
277
278 static int string_list_set_helper_option(struct helper_data *data,
279                                          const char *name,
280                                          struct string_list *list)
281 {
282         struct strbuf buf = STRBUF_INIT;
283         int i, ret = 0;
284
285         for (i = 0; i < list->nr; i++) {
286                 strbuf_addf(&buf, "option %s ", name);
287                 quote_c_style(list->items[i].string, &buf, NULL, 0);
288                 strbuf_addch(&buf, '\n');
289
290                 if ((ret = strbuf_set_helper_option(data, &buf)))
291                         break;
292                 strbuf_reset(&buf);
293         }
294         strbuf_release(&buf);
295         return ret;
296 }
297
298 static int set_helper_option(struct transport *transport,
299                           const char *name, const char *value)
300 {
301         struct helper_data *data = transport->data;
302         struct strbuf buf = STRBUF_INIT;
303         int i, ret, is_bool = 0;
304
305         get_helper(transport);
306
307         if (!data->option)
308                 return 1;
309
310         if (!strcmp(name, "deepen-not"))
311                 return string_list_set_helper_option(data, name,
312                                                      (struct string_list *)value);
313
314         for (i = 0; i < ARRAY_SIZE(unsupported_options); i++) {
315                 if (!strcmp(name, unsupported_options[i]))
316                         return 1;
317         }
318
319         for (i = 0; i < ARRAY_SIZE(boolean_options); i++) {
320                 if (!strcmp(name, boolean_options[i])) {
321                         is_bool = 1;
322                         break;
323                 }
324         }
325
326         strbuf_addf(&buf, "option %s ", name);
327         if (is_bool)
328                 strbuf_addstr(&buf, value ? "true" : "false");
329         else
330                 quote_c_style(value, &buf, NULL, 0);
331         strbuf_addch(&buf, '\n');
332
333         ret = strbuf_set_helper_option(data, &buf);
334         strbuf_release(&buf);
335         return ret;
336 }
337
338 static void standard_options(struct transport *t)
339 {
340         char buf[16];
341         int v = t->verbose;
342
343         set_helper_option(t, "progress", t->progress ? "true" : "false");
344
345         xsnprintf(buf, sizeof(buf), "%d", v + 1);
346         set_helper_option(t, "verbosity", buf);
347
348         switch (t->family) {
349         case TRANSPORT_FAMILY_ALL:
350                 /*
351                  * this is already the default,
352                  * do not break old remote helpers by setting "all" here
353                  */
354                 break;
355         case TRANSPORT_FAMILY_IPV4:
356                 set_helper_option(t, "family", "ipv4");
357                 break;
358         case TRANSPORT_FAMILY_IPV6:
359                 set_helper_option(t, "family", "ipv6");
360                 break;
361         }
362 }
363
364 static int release_helper(struct transport *transport)
365 {
366         int res = 0;
367         struct helper_data *data = transport->data;
368         refspec_clear(&data->rs);
369         res = disconnect_helper(transport);
370         free(transport->data);
371         return res;
372 }
373
374 static int fetch_with_fetch(struct transport *transport,
375                             int nr_heads, struct ref **to_fetch)
376 {
377         struct helper_data *data = transport->data;
378         int i;
379         struct strbuf buf = STRBUF_INIT;
380
381         for (i = 0; i < nr_heads; i++) {
382                 const struct ref *posn = to_fetch[i];
383                 if (posn->status & REF_STATUS_UPTODATE)
384                         continue;
385
386                 strbuf_addf(&buf, "fetch %s %s\n",
387                             oid_to_hex(&posn->old_oid),
388                             posn->symref ? posn->symref : posn->name);
389         }
390
391         strbuf_addch(&buf, '\n');
392         sendline(data, &buf);
393
394         while (1) {
395                 if (recvline(data, &buf))
396                         exit(128);
397
398                 if (starts_with(buf.buf, "lock ")) {
399                         const char *name = buf.buf + 5;
400                         if (transport->pack_lockfile)
401                                 warning(_("%s also locked %s"), data->name, name);
402                         else
403                                 transport->pack_lockfile = xstrdup(name);
404                 }
405                 else if (data->check_connectivity &&
406                          data->transport_options.check_self_contained_and_connected &&
407                          !strcmp(buf.buf, "connectivity-ok"))
408                         data->transport_options.self_contained_and_connected = 1;
409                 else if (!buf.len)
410                         break;
411                 else
412                         warning(_("%s unexpectedly said: '%s'"), data->name, buf.buf);
413         }
414         strbuf_release(&buf);
415         return 0;
416 }
417
418 static int get_importer(struct transport *transport, struct child_process *fastimport)
419 {
420         struct child_process *helper = get_helper(transport);
421         struct helper_data *data = transport->data;
422         int cat_blob_fd, code;
423         child_process_init(fastimport);
424         fastimport->in = helper->out;
425         argv_array_push(&fastimport->args, "fast-import");
426         argv_array_push(&fastimport->args, debug ? "--stats" : "--quiet");
427
428         if (data->bidi_import) {
429                 cat_blob_fd = xdup(helper->in);
430                 argv_array_pushf(&fastimport->args, "--cat-blob-fd=%d", cat_blob_fd);
431         }
432         fastimport->git_cmd = 1;
433
434         code = start_command(fastimport);
435         return code;
436 }
437
438 static int get_exporter(struct transport *transport,
439                         struct child_process *fastexport,
440                         struct string_list *revlist_args)
441 {
442         struct helper_data *data = transport->data;
443         struct child_process *helper = get_helper(transport);
444         int i;
445
446         child_process_init(fastexport);
447
448         /* we need to duplicate helper->in because we want to use it after
449          * fastexport is done with it. */
450         fastexport->out = dup(helper->in);
451         argv_array_push(&fastexport->args, "fast-export");
452         argv_array_push(&fastexport->args, "--use-done-feature");
453         argv_array_push(&fastexport->args, data->signed_tags ?
454                 "--signed-tags=verbatim" : "--signed-tags=warn-strip");
455         if (data->export_marks)
456                 argv_array_pushf(&fastexport->args, "--export-marks=%s.tmp", data->export_marks);
457         if (data->import_marks)
458                 argv_array_pushf(&fastexport->args, "--import-marks=%s", data->import_marks);
459
460         for (i = 0; i < revlist_args->nr; i++)
461                 argv_array_push(&fastexport->args, revlist_args->items[i].string);
462
463         fastexport->git_cmd = 1;
464         return start_command(fastexport);
465 }
466
467 static int fetch_with_import(struct transport *transport,
468                              int nr_heads, struct ref **to_fetch)
469 {
470         struct child_process fastimport;
471         struct helper_data *data = transport->data;
472         int i;
473         struct ref *posn;
474         struct strbuf buf = STRBUF_INIT;
475
476         get_helper(transport);
477
478         if (get_importer(transport, &fastimport))
479                 die(_("couldn't run fast-import"));
480
481         for (i = 0; i < nr_heads; i++) {
482                 posn = to_fetch[i];
483                 if (posn->status & REF_STATUS_UPTODATE)
484                         continue;
485
486                 strbuf_addf(&buf, "import %s\n",
487                             posn->symref ? posn->symref : posn->name);
488                 sendline(data, &buf);
489                 strbuf_reset(&buf);
490         }
491
492         write_constant(data->helper->in, "\n");
493         /*
494          * remote-helpers that advertise the bidi-import capability are required to
495          * buffer the complete batch of import commands until this newline before
496          * sending data to fast-import.
497          * These helpers read back data from fast-import on their stdin, which could
498          * be mixed with import commands, otherwise.
499          */
500
501         if (finish_command(&fastimport))
502                 die(_("error while running fast-import"));
503
504         /*
505          * The fast-import stream of a remote helper that advertises
506          * the "refspec" capability writes to the refs named after the
507          * right hand side of the first refspec matching each ref we
508          * were fetching.
509          *
510          * (If no "refspec" capability was specified, for historical
511          * reasons we default to the equivalent of *:*.)
512          *
513          * Store the result in to_fetch[i].old_sha1.  Callers such
514          * as "git fetch" can use the value to write feedback to the
515          * terminal, populate FETCH_HEAD, and determine what new value
516          * should be written to peer_ref if the update is a
517          * fast-forward or this is a forced update.
518          */
519         for (i = 0; i < nr_heads; i++) {
520                 char *private, *name;
521                 posn = to_fetch[i];
522                 if (posn->status & REF_STATUS_UPTODATE)
523                         continue;
524                 name = posn->symref ? posn->symref : posn->name;
525                 if (data->rs.nr)
526                         private = apply_refspecs(&data->rs, name);
527                 else
528                         private = xstrdup(name);
529                 if (private) {
530                         if (read_ref(private, &posn->old_oid) < 0)
531                                 die(_("could not read ref %s"), private);
532                         free(private);
533                 }
534         }
535         strbuf_release(&buf);
536         return 0;
537 }
538
539 static int run_connect(struct transport *transport, struct strbuf *cmdbuf)
540 {
541         struct helper_data *data = transport->data;
542         int ret = 0;
543         int duped;
544         FILE *input;
545         struct child_process *helper;
546
547         helper = get_helper(transport);
548
549         /*
550          * Yes, dup the pipe another time, as we need unbuffered version
551          * of input pipe as FILE*. fclose() closes the underlying fd and
552          * stream buffering only can be changed before first I/O operation
553          * on it.
554          */
555         duped = dup(helper->out);
556         if (duped < 0)
557                 die_errno(_("can't dup helper output fd"));
558         input = xfdopen(duped, "r");
559         setvbuf(input, NULL, _IONBF, 0);
560
561         sendline(data, cmdbuf);
562         if (recvline_fh(input, cmdbuf))
563                 exit(128);
564
565         if (!strcmp(cmdbuf->buf, "")) {
566                 data->no_disconnect_req = 1;
567                 if (debug)
568                         fprintf(stderr, "Debug: Smart transport connection "
569                                 "ready.\n");
570                 ret = 1;
571         } else if (!strcmp(cmdbuf->buf, "fallback")) {
572                 if (debug)
573                         fprintf(stderr, "Debug: Falling back to dumb "
574                                 "transport.\n");
575         } else {
576                 die(_(_("unknown response to connect: %s")),
577                     cmdbuf->buf);
578         }
579
580         fclose(input);
581         return ret;
582 }
583
584 static int process_connect_service(struct transport *transport,
585                                    const char *name, const char *exec)
586 {
587         struct helper_data *data = transport->data;
588         struct strbuf cmdbuf = STRBUF_INIT;
589         int ret = 0;
590
591         /*
592          * Handle --upload-pack and friends. This is fire and forget...
593          * just warn if it fails.
594          */
595         if (strcmp(name, exec)) {
596                 int r = set_helper_option(transport, "servpath", exec);
597                 if (r > 0)
598                         warning(_("setting remote service path not supported by protocol"));
599                 else if (r < 0)
600                         warning(_("invalid remote service path"));
601         }
602
603         if (data->connect) {
604                 strbuf_addf(&cmdbuf, "connect %s\n", name);
605                 ret = run_connect(transport, &cmdbuf);
606         } else if (data->stateless_connect &&
607                    (get_protocol_version_config() == protocol_v2) &&
608                    !strcmp("git-upload-pack", name)) {
609                 strbuf_addf(&cmdbuf, "stateless-connect %s\n", name);
610                 ret = run_connect(transport, &cmdbuf);
611                 if (ret)
612                         transport->stateless_rpc = 1;
613         }
614
615         strbuf_release(&cmdbuf);
616         return ret;
617 }
618
619 static int process_connect(struct transport *transport,
620                                      int for_push)
621 {
622         struct helper_data *data = transport->data;
623         const char *name;
624         const char *exec;
625
626         name = for_push ? "git-receive-pack" : "git-upload-pack";
627         if (for_push)
628                 exec = data->transport_options.receivepack;
629         else
630                 exec = data->transport_options.uploadpack;
631
632         return process_connect_service(transport, name, exec);
633 }
634
635 static int connect_helper(struct transport *transport, const char *name,
636                    const char *exec, int fd[2])
637 {
638         struct helper_data *data = transport->data;
639
640         /* Get_helper so connect is inited. */
641         get_helper(transport);
642         if (!data->connect)
643                 die(_("operation not supported by protocol"));
644
645         if (!process_connect_service(transport, name, exec))
646                 die(_("can't connect to subservice %s"), name);
647
648         fd[0] = data->helper->out;
649         fd[1] = data->helper->in;
650         return 0;
651 }
652
653 static int fetch(struct transport *transport,
654                  int nr_heads, struct ref **to_fetch,
655                  struct ref **fetched_refs)
656 {
657         struct helper_data *data = transport->data;
658         int i, count;
659
660         if (process_connect(transport, 0)) {
661                 do_take_over(transport);
662                 return transport->vtable->fetch(transport, nr_heads, to_fetch,
663                                                 fetched_refs);
664         }
665
666         count = 0;
667         for (i = 0; i < nr_heads; i++)
668                 if (!(to_fetch[i]->status & REF_STATUS_UPTODATE))
669                         count++;
670
671         if (!count)
672                 return 0;
673
674         if (data->check_connectivity &&
675             data->transport_options.check_self_contained_and_connected)
676                 set_helper_option(transport, "check-connectivity", "true");
677
678         if (transport->cloning)
679                 set_helper_option(transport, "cloning", "true");
680
681         if (data->transport_options.update_shallow)
682                 set_helper_option(transport, "update-shallow", "true");
683
684         if (data->transport_options.filter_options.choice)
685                 set_helper_option(
686                         transport, "filter",
687                         data->transport_options.filter_options.filter_spec);
688
689         if (data->transport_options.negotiation_tips)
690                 warning("Ignoring --negotiation-tip because the protocol does not support it.");
691
692         if (data->fetch)
693                 return fetch_with_fetch(transport, nr_heads, to_fetch);
694
695         if (data->import)
696                 return fetch_with_import(transport, nr_heads, to_fetch);
697
698         return -1;
699 }
700
701 static int push_update_ref_status(struct strbuf *buf,
702                                    struct ref **ref,
703                                    struct ref *remote_refs)
704 {
705         char *refname, *msg;
706         int status, forced = 0;
707
708         if (starts_with(buf->buf, "ok ")) {
709                 status = REF_STATUS_OK;
710                 refname = buf->buf + 3;
711         } else if (starts_with(buf->buf, "error ")) {
712                 status = REF_STATUS_REMOTE_REJECT;
713                 refname = buf->buf + 6;
714         } else
715                 die(_("expected ok/error, helper said '%s'"), buf->buf);
716
717         msg = strchr(refname, ' ');
718         if (msg) {
719                 struct strbuf msg_buf = STRBUF_INIT;
720                 const char *end;
721
722                 *msg++ = '\0';
723                 if (!unquote_c_style(&msg_buf, msg, &end))
724                         msg = strbuf_detach(&msg_buf, NULL);
725                 else
726                         msg = xstrdup(msg);
727                 strbuf_release(&msg_buf);
728
729                 if (!strcmp(msg, "no match")) {
730                         status = REF_STATUS_NONE;
731                         FREE_AND_NULL(msg);
732                 }
733                 else if (!strcmp(msg, "up to date")) {
734                         status = REF_STATUS_UPTODATE;
735                         FREE_AND_NULL(msg);
736                 }
737                 else if (!strcmp(msg, "non-fast forward")) {
738                         status = REF_STATUS_REJECT_NONFASTFORWARD;
739                         FREE_AND_NULL(msg);
740                 }
741                 else if (!strcmp(msg, "already exists")) {
742                         status = REF_STATUS_REJECT_ALREADY_EXISTS;
743                         FREE_AND_NULL(msg);
744                 }
745                 else if (!strcmp(msg, "fetch first")) {
746                         status = REF_STATUS_REJECT_FETCH_FIRST;
747                         FREE_AND_NULL(msg);
748                 }
749                 else if (!strcmp(msg, "needs force")) {
750                         status = REF_STATUS_REJECT_NEEDS_FORCE;
751                         FREE_AND_NULL(msg);
752                 }
753                 else if (!strcmp(msg, "stale info")) {
754                         status = REF_STATUS_REJECT_STALE;
755                         FREE_AND_NULL(msg);
756                 }
757                 else if (!strcmp(msg, "forced update")) {
758                         forced = 1;
759                         FREE_AND_NULL(msg);
760                 }
761         }
762
763         if (*ref)
764                 *ref = find_ref_by_name(*ref, refname);
765         if (!*ref)
766                 *ref = find_ref_by_name(remote_refs, refname);
767         if (!*ref) {
768                 warning(_("helper reported unexpected status of %s"), refname);
769                 return 1;
770         }
771
772         if ((*ref)->status != REF_STATUS_NONE) {
773                 /*
774                  * Earlier, the ref was marked not to be pushed, so ignore the ref
775                  * status reported by the remote helper if the latter is 'no match'.
776                  */
777                 if (status == REF_STATUS_NONE)
778                         return 1;
779         }
780
781         (*ref)->status = status;
782         (*ref)->forced_update |= forced;
783         (*ref)->remote_status = msg;
784         return !(status == REF_STATUS_OK);
785 }
786
787 static int push_update_refs_status(struct helper_data *data,
788                                     struct ref *remote_refs,
789                                     int flags)
790 {
791         struct strbuf buf = STRBUF_INIT;
792         struct ref *ref = remote_refs;
793         int ret = 0;
794
795         for (;;) {
796                 char *private;
797
798                 if (recvline(data, &buf)) {
799                         ret = 1;
800                         break;
801                 }
802
803                 if (!buf.len)
804                         break;
805
806                 if (push_update_ref_status(&buf, &ref, remote_refs))
807                         continue;
808
809                 if (flags & TRANSPORT_PUSH_DRY_RUN || !data->rs.nr || data->no_private_update)
810                         continue;
811
812                 /* propagate back the update to the remote namespace */
813                 private = apply_refspecs(&data->rs, ref->name);
814                 if (!private)
815                         continue;
816                 update_ref("update by helper", private, &ref->new_oid, NULL,
817                            0, 0);
818                 free(private);
819         }
820         strbuf_release(&buf);
821         return ret;
822 }
823
824 static void set_common_push_options(struct transport *transport,
825                                    const char *name, int flags)
826 {
827         if (flags & TRANSPORT_PUSH_DRY_RUN) {
828                 if (set_helper_option(transport, "dry-run", "true") != 0)
829                         die(_("helper %s does not support dry-run"), name);
830         } else if (flags & TRANSPORT_PUSH_CERT_ALWAYS) {
831                 if (set_helper_option(transport, TRANS_OPT_PUSH_CERT, "true") != 0)
832                         die(_("helper %s does not support --signed"), name);
833         } else if (flags & TRANSPORT_PUSH_CERT_IF_ASKED) {
834                 if (set_helper_option(transport, TRANS_OPT_PUSH_CERT, "if-asked") != 0)
835                         die(_("helper %s does not support --signed=if-asked"), name);
836         }
837
838         if (flags & TRANSPORT_PUSH_OPTIONS) {
839                 struct string_list_item *item;
840                 for_each_string_list_item(item, transport->push_options)
841                         if (set_helper_option(transport, "push-option", item->string) != 0)
842                                 die(_("helper %s does not support 'push-option'"), name);
843         }
844 }
845
846 static int push_refs_with_push(struct transport *transport,
847                                struct ref *remote_refs, int flags)
848 {
849         int force_all = flags & TRANSPORT_PUSH_FORCE;
850         int mirror = flags & TRANSPORT_PUSH_MIRROR;
851         struct helper_data *data = transport->data;
852         struct strbuf buf = STRBUF_INIT;
853         struct ref *ref;
854         struct string_list cas_options = STRING_LIST_INIT_DUP;
855         struct string_list_item *cas_option;
856
857         get_helper(transport);
858         if (!data->push)
859                 return 1;
860
861         for (ref = remote_refs; ref; ref = ref->next) {
862                 if (!ref->peer_ref && !mirror)
863                         continue;
864
865                 /* Check for statuses set by set_ref_status_for_push() */
866                 switch (ref->status) {
867                 case REF_STATUS_REJECT_NONFASTFORWARD:
868                 case REF_STATUS_REJECT_STALE:
869                 case REF_STATUS_REJECT_ALREADY_EXISTS:
870                 case REF_STATUS_UPTODATE:
871                         continue;
872                 default:
873                         ; /* do nothing */
874                 }
875
876                 if (force_all)
877                         ref->force = 1;
878
879                 strbuf_addstr(&buf, "push ");
880                 if (!ref->deletion) {
881                         if (ref->force)
882                                 strbuf_addch(&buf, '+');
883                         if (ref->peer_ref)
884                                 strbuf_addstr(&buf, ref->peer_ref->name);
885                         else
886                                 strbuf_addstr(&buf, oid_to_hex(&ref->new_oid));
887                 }
888                 strbuf_addch(&buf, ':');
889                 strbuf_addstr(&buf, ref->name);
890                 strbuf_addch(&buf, '\n');
891
892                 /*
893                  * The "--force-with-lease" options without explicit
894                  * values to expect have already been expanded into
895                  * the ref->old_oid_expect[] field; we can ignore
896                  * transport->smart_options->cas altogether and instead
897                  * can enumerate them from the refs.
898                  */
899                 if (ref->expect_old_sha1) {
900                         struct strbuf cas = STRBUF_INIT;
901                         strbuf_addf(&cas, "%s:%s",
902                                     ref->name, oid_to_hex(&ref->old_oid_expect));
903                         string_list_append_nodup(&cas_options,
904                                                  strbuf_detach(&cas, NULL));
905                 }
906         }
907         if (buf.len == 0) {
908                 string_list_clear(&cas_options, 0);
909                 return 0;
910         }
911
912         for_each_string_list_item(cas_option, &cas_options)
913                 set_helper_option(transport, "cas", cas_option->string);
914         set_common_push_options(transport, data->name, flags);
915
916         strbuf_addch(&buf, '\n');
917         sendline(data, &buf);
918         strbuf_release(&buf);
919         string_list_clear(&cas_options, 0);
920
921         return push_update_refs_status(data, remote_refs, flags);
922 }
923
924 static int push_refs_with_export(struct transport *transport,
925                 struct ref *remote_refs, int flags)
926 {
927         struct ref *ref;
928         struct child_process *helper, exporter;
929         struct helper_data *data = transport->data;
930         struct string_list revlist_args = STRING_LIST_INIT_DUP;
931         struct strbuf buf = STRBUF_INIT;
932
933         if (!data->rs.nr)
934                 die(_("remote-helper doesn't support push; refspec needed"));
935
936         set_common_push_options(transport, data->name, flags);
937         if (flags & TRANSPORT_PUSH_FORCE) {
938                 if (set_helper_option(transport, "force", "true") != 0)
939                         warning(_("helper %s does not support 'force'"), data->name);
940         }
941
942         helper = get_helper(transport);
943
944         write_constant(helper->in, "export\n");
945
946         for (ref = remote_refs; ref; ref = ref->next) {
947                 char *private;
948                 struct object_id oid;
949
950                 private = apply_refspecs(&data->rs, ref->name);
951                 if (private && !get_oid(private, &oid)) {
952                         strbuf_addf(&buf, "^%s", private);
953                         string_list_append_nodup(&revlist_args,
954                                                  strbuf_detach(&buf, NULL));
955                         oidcpy(&ref->old_oid, &oid);
956                 }
957                 free(private);
958
959                 if (ref->peer_ref) {
960                         if (strcmp(ref->name, ref->peer_ref->name)) {
961                                 if (!ref->deletion) {
962                                         const char *name;
963                                         int flag;
964
965                                         /* Follow symbolic refs (mainly for HEAD). */
966                                         name = resolve_ref_unsafe(ref->peer_ref->name,
967                                                                   RESOLVE_REF_READING,
968                                                                   &oid, &flag);
969                                         if (!name || !(flag & REF_ISSYMREF))
970                                                 name = ref->peer_ref->name;
971
972                                         strbuf_addf(&buf, "%s:%s", name, ref->name);
973                                 } else
974                                         strbuf_addf(&buf, ":%s", ref->name);
975
976                                 string_list_append(&revlist_args, "--refspec");
977                                 string_list_append(&revlist_args, buf.buf);
978                                 strbuf_release(&buf);
979                         }
980                         if (!ref->deletion)
981                                 string_list_append(&revlist_args, ref->peer_ref->name);
982                 }
983         }
984
985         if (get_exporter(transport, &exporter, &revlist_args))
986                 die(_("couldn't run fast-export"));
987
988         string_list_clear(&revlist_args, 1);
989
990         if (finish_command(&exporter))
991                 die(_("error while running fast-export"));
992         if (push_update_refs_status(data, remote_refs, flags))
993                 return 1;
994
995         if (data->export_marks) {
996                 strbuf_addf(&buf, "%s.tmp", data->export_marks);
997                 rename(buf.buf, data->export_marks);
998                 strbuf_release(&buf);
999         }
1000
1001         return 0;
1002 }
1003
1004 static int push_refs(struct transport *transport,
1005                 struct ref *remote_refs, int flags)
1006 {
1007         struct helper_data *data = transport->data;
1008
1009         if (process_connect(transport, 1)) {
1010                 do_take_over(transport);
1011                 return transport->vtable->push_refs(transport, remote_refs, flags);
1012         }
1013
1014         if (!remote_refs) {
1015                 fprintf(stderr,
1016                         _("No refs in common and none specified; doing nothing.\n"
1017                           "Perhaps you should specify a branch such as 'master'.\n"));
1018                 return 0;
1019         }
1020
1021         if (data->push)
1022                 return push_refs_with_push(transport, remote_refs, flags);
1023
1024         if (data->export)
1025                 return push_refs_with_export(transport, remote_refs, flags);
1026
1027         return -1;
1028 }
1029
1030
1031 static int has_attribute(const char *attrs, const char *attr) {
1032         int len;
1033         if (!attrs)
1034                 return 0;
1035
1036         len = strlen(attr);
1037         for (;;) {
1038                 const char *space = strchrnul(attrs, ' ');
1039                 if (len == space - attrs && !strncmp(attrs, attr, len))
1040                         return 1;
1041                 if (!*space)
1042                         return 0;
1043                 attrs = space + 1;
1044         }
1045 }
1046
1047 static struct ref *get_refs_list(struct transport *transport, int for_push,
1048                                  const struct argv_array *ref_prefixes)
1049 {
1050         struct helper_data *data = transport->data;
1051         struct child_process *helper;
1052         struct ref *ret = NULL;
1053         struct ref **tail = &ret;
1054         struct ref *posn;
1055         struct strbuf buf = STRBUF_INIT;
1056
1057         helper = get_helper(transport);
1058
1059         if (process_connect(transport, for_push)) {
1060                 do_take_over(transport);
1061                 return transport->vtable->get_refs_list(transport, for_push, ref_prefixes);
1062         }
1063
1064         if (data->push && for_push)
1065                 write_str_in_full(helper->in, "list for-push\n");
1066         else
1067                 write_str_in_full(helper->in, "list\n");
1068
1069         while (1) {
1070                 char *eov, *eon;
1071                 if (recvline(data, &buf))
1072                         exit(128);
1073
1074                 if (!*buf.buf)
1075                         break;
1076
1077                 eov = strchr(buf.buf, ' ');
1078                 if (!eov)
1079                         die(_("malformed response in ref list: %s"), buf.buf);
1080                 eon = strchr(eov + 1, ' ');
1081                 *eov = '\0';
1082                 if (eon)
1083                         *eon = '\0';
1084                 *tail = alloc_ref(eov + 1);
1085                 if (buf.buf[0] == '@')
1086                         (*tail)->symref = xstrdup(buf.buf + 1);
1087                 else if (buf.buf[0] != '?')
1088                         get_oid_hex(buf.buf, &(*tail)->old_oid);
1089                 if (eon) {
1090                         if (has_attribute(eon + 1, "unchanged")) {
1091                                 (*tail)->status |= REF_STATUS_UPTODATE;
1092                                 if (read_ref((*tail)->name, &(*tail)->old_oid) < 0)
1093                                         die(_("could not read ref %s"),
1094                                             (*tail)->name);
1095                         }
1096                 }
1097                 tail = &((*tail)->next);
1098         }
1099         if (debug)
1100                 fprintf(stderr, "Debug: Read ref listing.\n");
1101         strbuf_release(&buf);
1102
1103         for (posn = ret; posn; posn = posn->next)
1104                 resolve_remote_symref(posn, ret);
1105
1106         return ret;
1107 }
1108
1109 static struct transport_vtable vtable = {
1110         set_helper_option,
1111         get_refs_list,
1112         fetch,
1113         push_refs,
1114         connect_helper,
1115         release_helper
1116 };
1117
1118 int transport_helper_init(struct transport *transport, const char *name)
1119 {
1120         struct helper_data *data = xcalloc(1, sizeof(*data));
1121         data->name = name;
1122
1123         transport_check_allowed(name);
1124
1125         if (getenv("GIT_TRANSPORT_HELPER_DEBUG"))
1126                 debug = 1;
1127
1128         transport->data = data;
1129         transport->vtable = &vtable;
1130         transport->smart_options = &(data->transport_options);
1131         return 0;
1132 }
1133
1134 /*
1135  * Linux pipes can buffer 65536 bytes at once (and most platforms can
1136  * buffer less), so attempt reads and writes with up to that size.
1137  */
1138 #define BUFFERSIZE 65536
1139 /* This should be enough to hold debugging message. */
1140 #define PBUFFERSIZE 8192
1141
1142 /* Print bidirectional transfer loop debug message. */
1143 __attribute__((format (printf, 1, 2)))
1144 static void transfer_debug(const char *fmt, ...)
1145 {
1146         /*
1147          * NEEDSWORK: This function is sometimes used from multiple threads, and
1148          * we end up using debug_enabled racily. That "should not matter" since
1149          * we always write the same value, but it's still wrong. This function
1150          * is listed in .tsan-suppressions for the time being.
1151          */
1152
1153         va_list args;
1154         char msgbuf[PBUFFERSIZE];
1155         static int debug_enabled = -1;
1156
1157         if (debug_enabled < 0)
1158                 debug_enabled = getenv("GIT_TRANSLOOP_DEBUG") ? 1 : 0;
1159         if (!debug_enabled)
1160                 return;
1161
1162         va_start(args, fmt);
1163         vsnprintf(msgbuf, PBUFFERSIZE, fmt, args);
1164         va_end(args);
1165         fprintf(stderr, "Transfer loop debugging: %s\n", msgbuf);
1166 }
1167
1168 /* Stream state: More data may be coming in this direction. */
1169 #define SSTATE_TRANSFERRING 0
1170 /*
1171  * Stream state: No more data coming in this direction, flushing rest of
1172  * data.
1173  */
1174 #define SSTATE_FLUSHING 1
1175 /* Stream state: Transfer in this direction finished. */
1176 #define SSTATE_FINISHED 2
1177
1178 #define STATE_NEEDS_READING(state) ((state) <= SSTATE_TRANSFERRING)
1179 #define STATE_NEEDS_WRITING(state) ((state) <= SSTATE_FLUSHING)
1180 #define STATE_NEEDS_CLOSING(state) ((state) == SSTATE_FLUSHING)
1181
1182 /* Unidirectional transfer. */
1183 struct unidirectional_transfer {
1184         /* Source */
1185         int src;
1186         /* Destination */
1187         int dest;
1188         /* Is source socket? */
1189         int src_is_sock;
1190         /* Is destination socket? */
1191         int dest_is_sock;
1192         /* Transfer state (TRANSFERRING/FLUSHING/FINISHED) */
1193         int state;
1194         /* Buffer. */
1195         char buf[BUFFERSIZE];
1196         /* Buffer used. */
1197         size_t bufuse;
1198         /* Name of source. */
1199         const char *src_name;
1200         /* Name of destination. */
1201         const char *dest_name;
1202 };
1203
1204 /* Closes the target (for writing) if transfer has finished. */
1205 static void udt_close_if_finished(struct unidirectional_transfer *t)
1206 {
1207         if (STATE_NEEDS_CLOSING(t->state) && !t->bufuse) {
1208                 t->state = SSTATE_FINISHED;
1209                 if (t->dest_is_sock)
1210                         shutdown(t->dest, SHUT_WR);
1211                 else
1212                         close(t->dest);
1213                 transfer_debug("Closed %s.", t->dest_name);
1214         }
1215 }
1216
1217 /*
1218  * Tries to read data from source into buffer. If buffer is full,
1219  * no data is read. Returns 0 on success, -1 on error.
1220  */
1221 static int udt_do_read(struct unidirectional_transfer *t)
1222 {
1223         ssize_t bytes;
1224
1225         if (t->bufuse == BUFFERSIZE)
1226                 return 0;       /* No space for more. */
1227
1228         transfer_debug("%s is readable", t->src_name);
1229         bytes = read(t->src, t->buf + t->bufuse, BUFFERSIZE - t->bufuse);
1230         if (bytes < 0 && errno != EWOULDBLOCK && errno != EAGAIN &&
1231                 errno != EINTR) {
1232                 error_errno(_("read(%s) failed"), t->src_name);
1233                 return -1;
1234         } else if (bytes == 0) {
1235                 transfer_debug("%s EOF (with %i bytes in buffer)",
1236                         t->src_name, (int)t->bufuse);
1237                 t->state = SSTATE_FLUSHING;
1238         } else if (bytes > 0) {
1239                 t->bufuse += bytes;
1240                 transfer_debug("Read %i bytes from %s (buffer now at %i)",
1241                         (int)bytes, t->src_name, (int)t->bufuse);
1242         }
1243         return 0;
1244 }
1245
1246 /* Tries to write data from buffer into destination. If buffer is empty,
1247  * no data is written. Returns 0 on success, -1 on error.
1248  */
1249 static int udt_do_write(struct unidirectional_transfer *t)
1250 {
1251         ssize_t bytes;
1252
1253         if (t->bufuse == 0)
1254                 return 0;       /* Nothing to write. */
1255
1256         transfer_debug("%s is writable", t->dest_name);
1257         bytes = xwrite(t->dest, t->buf, t->bufuse);
1258         if (bytes < 0 && errno != EWOULDBLOCK) {
1259                 error_errno(_("write(%s) failed"), t->dest_name);
1260                 return -1;
1261         } else if (bytes > 0) {
1262                 t->bufuse -= bytes;
1263                 if (t->bufuse)
1264                         memmove(t->buf, t->buf + bytes, t->bufuse);
1265                 transfer_debug("Wrote %i bytes to %s (buffer now at %i)",
1266                         (int)bytes, t->dest_name, (int)t->bufuse);
1267         }
1268         return 0;
1269 }
1270
1271
1272 /* State of bidirectional transfer loop. */
1273 struct bidirectional_transfer_state {
1274         /* Direction from program to git. */
1275         struct unidirectional_transfer ptg;
1276         /* Direction from git to program. */
1277         struct unidirectional_transfer gtp;
1278 };
1279
1280 static void *udt_copy_task_routine(void *udt)
1281 {
1282         struct unidirectional_transfer *t = (struct unidirectional_transfer *)udt;
1283         while (t->state != SSTATE_FINISHED) {
1284                 if (STATE_NEEDS_READING(t->state))
1285                         if (udt_do_read(t))
1286                                 return NULL;
1287                 if (STATE_NEEDS_WRITING(t->state))
1288                         if (udt_do_write(t))
1289                                 return NULL;
1290                 if (STATE_NEEDS_CLOSING(t->state))
1291                         udt_close_if_finished(t);
1292         }
1293         return udt;     /* Just some non-NULL value. */
1294 }
1295
1296 #ifndef NO_PTHREADS
1297
1298 /*
1299  * Join thread, with appropriate errors on failure. Name is name for the
1300  * thread (for error messages). Returns 0 on success, 1 on failure.
1301  */
1302 static int tloop_join(pthread_t thread, const char *name)
1303 {
1304         int err;
1305         void *tret;
1306         err = pthread_join(thread, &tret);
1307         if (!tret) {
1308                 error(_("%s thread failed"), name);
1309                 return 1;
1310         }
1311         if (err) {
1312                 error(_("%s thread failed to join: %s"), name, strerror(err));
1313                 return 1;
1314         }
1315         return 0;
1316 }
1317
1318 /*
1319  * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1320  * -1 on failure.
1321  */
1322 static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1323 {
1324         pthread_t gtp_thread;
1325         pthread_t ptg_thread;
1326         int err;
1327         int ret = 0;
1328         err = pthread_create(&gtp_thread, NULL, udt_copy_task_routine,
1329                 &s->gtp);
1330         if (err)
1331                 die(_("can't start thread for copying data: %s"), strerror(err));
1332         err = pthread_create(&ptg_thread, NULL, udt_copy_task_routine,
1333                 &s->ptg);
1334         if (err)
1335                 die(_("can't start thread for copying data: %s"), strerror(err));
1336
1337         ret |= tloop_join(gtp_thread, "Git to program copy");
1338         ret |= tloop_join(ptg_thread, "Program to git copy");
1339         return ret;
1340 }
1341 #else
1342
1343 /* Close the source and target (for writing) for transfer. */
1344 static void udt_kill_transfer(struct unidirectional_transfer *t)
1345 {
1346         t->state = SSTATE_FINISHED;
1347         /*
1348          * Socket read end left open isn't a disaster if nobody
1349          * attempts to read from it (mingw compat headers do not
1350          * have SHUT_RD)...
1351          *
1352          * We can't fully close the socket since otherwise gtp
1353          * task would first close the socket it sends data to
1354          * while closing the ptg file descriptors.
1355          */
1356         if (!t->src_is_sock)
1357                 close(t->src);
1358         if (t->dest_is_sock)
1359                 shutdown(t->dest, SHUT_WR);
1360         else
1361                 close(t->dest);
1362 }
1363
1364 /*
1365  * Join process, with appropriate errors on failure. Name is name for the
1366  * process (for error messages). Returns 0 on success, 1 on failure.
1367  */
1368 static int tloop_join(pid_t pid, const char *name)
1369 {
1370         int tret;
1371         if (waitpid(pid, &tret, 0) < 0) {
1372                 error_errno(_("%s process failed to wait"), name);
1373                 return 1;
1374         }
1375         if (!WIFEXITED(tret) || WEXITSTATUS(tret)) {
1376                 error(_("%s process failed"), name);
1377                 return 1;
1378         }
1379         return 0;
1380 }
1381
1382 /*
1383  * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1384  * -1 on failure.
1385  */
1386 static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1387 {
1388         pid_t pid1, pid2;
1389         int ret = 0;
1390
1391         /* Fork thread #1: git to program. */
1392         pid1 = fork();
1393         if (pid1 < 0)
1394                 die_errno(_("can't start thread for copying data"));
1395         else if (pid1 == 0) {
1396                 udt_kill_transfer(&s->ptg);
1397                 exit(udt_copy_task_routine(&s->gtp) ? 0 : 1);
1398         }
1399
1400         /* Fork thread #2: program to git. */
1401         pid2 = fork();
1402         if (pid2 < 0)
1403                 die_errno(_("can't start thread for copying data"));
1404         else if (pid2 == 0) {
1405                 udt_kill_transfer(&s->gtp);
1406                 exit(udt_copy_task_routine(&s->ptg) ? 0 : 1);
1407         }
1408
1409         /*
1410          * Close both streams in parent as to not interfere with
1411          * end of file detection and wait for both tasks to finish.
1412          */
1413         udt_kill_transfer(&s->gtp);
1414         udt_kill_transfer(&s->ptg);
1415         ret |= tloop_join(pid1, "Git to program copy");
1416         ret |= tloop_join(pid2, "Program to git copy");
1417         return ret;
1418 }
1419 #endif
1420
1421 /*
1422  * Copies data from stdin to output and from input to stdout simultaneously.
1423  * Additionally filtering through given filter. If filter is NULL, uses
1424  * identity filter.
1425  */
1426 int bidirectional_transfer_loop(int input, int output)
1427 {
1428         struct bidirectional_transfer_state state;
1429
1430         /* Fill the state fields. */
1431         state.ptg.src = input;
1432         state.ptg.dest = 1;
1433         state.ptg.src_is_sock = (input == output);
1434         state.ptg.dest_is_sock = 0;
1435         state.ptg.state = SSTATE_TRANSFERRING;
1436         state.ptg.bufuse = 0;
1437         state.ptg.src_name = "remote input";
1438         state.ptg.dest_name = "stdout";
1439
1440         state.gtp.src = 0;
1441         state.gtp.dest = output;
1442         state.gtp.src_is_sock = 0;
1443         state.gtp.dest_is_sock = (input == output);
1444         state.gtp.state = SSTATE_TRANSFERRING;
1445         state.gtp.bufuse = 0;
1446         state.gtp.src_name = "stdin";
1447         state.gtp.dest_name = "remote output";
1448
1449         return tloop_spawnwait_tasks(&state);
1450 }