Merge branch 'rj/sparse-flags'
[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 {
656         struct helper_data *data = transport->data;
657         int i, count;
658
659         if (process_connect(transport, 0)) {
660                 do_take_over(transport);
661                 return transport->vtable->fetch(transport, nr_heads, to_fetch);
662         }
663
664         count = 0;
665         for (i = 0; i < nr_heads; i++)
666                 if (!(to_fetch[i]->status & REF_STATUS_UPTODATE))
667                         count++;
668
669         if (!count)
670                 return 0;
671
672         if (data->check_connectivity &&
673             data->transport_options.check_self_contained_and_connected)
674                 set_helper_option(transport, "check-connectivity", "true");
675
676         if (transport->cloning)
677                 set_helper_option(transport, "cloning", "true");
678
679         if (data->transport_options.update_shallow)
680                 set_helper_option(transport, "update-shallow", "true");
681
682         if (data->transport_options.filter_options.choice) {
683                 struct strbuf expanded_filter_spec = STRBUF_INIT;
684                 expand_list_objects_filter_spec(
685                         &data->transport_options.filter_options,
686                         &expanded_filter_spec);
687                 set_helper_option(transport, "filter",
688                                   expanded_filter_spec.buf);
689                 strbuf_release(&expanded_filter_spec);
690         }
691
692         if (data->transport_options.negotiation_tips)
693                 warning("Ignoring --negotiation-tip because the protocol does not support it.");
694
695         if (data->fetch)
696                 return fetch_with_fetch(transport, nr_heads, to_fetch);
697
698         if (data->import)
699                 return fetch_with_import(transport, nr_heads, to_fetch);
700
701         return -1;
702 }
703
704 static int push_update_ref_status(struct strbuf *buf,
705                                    struct ref **ref,
706                                    struct ref *remote_refs)
707 {
708         char *refname, *msg;
709         int status, forced = 0;
710
711         if (starts_with(buf->buf, "ok ")) {
712                 status = REF_STATUS_OK;
713                 refname = buf->buf + 3;
714         } else if (starts_with(buf->buf, "error ")) {
715                 status = REF_STATUS_REMOTE_REJECT;
716                 refname = buf->buf + 6;
717         } else
718                 die(_("expected ok/error, helper said '%s'"), buf->buf);
719
720         msg = strchr(refname, ' ');
721         if (msg) {
722                 struct strbuf msg_buf = STRBUF_INIT;
723                 const char *end;
724
725                 *msg++ = '\0';
726                 if (!unquote_c_style(&msg_buf, msg, &end))
727                         msg = strbuf_detach(&msg_buf, NULL);
728                 else
729                         msg = xstrdup(msg);
730                 strbuf_release(&msg_buf);
731
732                 if (!strcmp(msg, "no match")) {
733                         status = REF_STATUS_NONE;
734                         FREE_AND_NULL(msg);
735                 }
736                 else if (!strcmp(msg, "up to date")) {
737                         status = REF_STATUS_UPTODATE;
738                         FREE_AND_NULL(msg);
739                 }
740                 else if (!strcmp(msg, "non-fast forward")) {
741                         status = REF_STATUS_REJECT_NONFASTFORWARD;
742                         FREE_AND_NULL(msg);
743                 }
744                 else if (!strcmp(msg, "already exists")) {
745                         status = REF_STATUS_REJECT_ALREADY_EXISTS;
746                         FREE_AND_NULL(msg);
747                 }
748                 else if (!strcmp(msg, "fetch first")) {
749                         status = REF_STATUS_REJECT_FETCH_FIRST;
750                         FREE_AND_NULL(msg);
751                 }
752                 else if (!strcmp(msg, "needs force")) {
753                         status = REF_STATUS_REJECT_NEEDS_FORCE;
754                         FREE_AND_NULL(msg);
755                 }
756                 else if (!strcmp(msg, "stale info")) {
757                         status = REF_STATUS_REJECT_STALE;
758                         FREE_AND_NULL(msg);
759                 }
760                 else if (!strcmp(msg, "forced update")) {
761                         forced = 1;
762                         FREE_AND_NULL(msg);
763                 }
764         }
765
766         if (*ref)
767                 *ref = find_ref_by_name(*ref, refname);
768         if (!*ref)
769                 *ref = find_ref_by_name(remote_refs, refname);
770         if (!*ref) {
771                 warning(_("helper reported unexpected status of %s"), refname);
772                 return 1;
773         }
774
775         if ((*ref)->status != REF_STATUS_NONE) {
776                 /*
777                  * Earlier, the ref was marked not to be pushed, so ignore the ref
778                  * status reported by the remote helper if the latter is 'no match'.
779                  */
780                 if (status == REF_STATUS_NONE)
781                         return 1;
782         }
783
784         (*ref)->status = status;
785         (*ref)->forced_update |= forced;
786         (*ref)->remote_status = msg;
787         return !(status == REF_STATUS_OK);
788 }
789
790 static int push_update_refs_status(struct helper_data *data,
791                                     struct ref *remote_refs,
792                                     int flags)
793 {
794         struct strbuf buf = STRBUF_INIT;
795         struct ref *ref = remote_refs;
796         int ret = 0;
797
798         for (;;) {
799                 char *private;
800
801                 if (recvline(data, &buf)) {
802                         ret = 1;
803                         break;
804                 }
805
806                 if (!buf.len)
807                         break;
808
809                 if (push_update_ref_status(&buf, &ref, remote_refs))
810                         continue;
811
812                 if (flags & TRANSPORT_PUSH_DRY_RUN || !data->rs.nr || data->no_private_update)
813                         continue;
814
815                 /* propagate back the update to the remote namespace */
816                 private = apply_refspecs(&data->rs, ref->name);
817                 if (!private)
818                         continue;
819                 update_ref("update by helper", private, &ref->new_oid, NULL,
820                            0, 0);
821                 free(private);
822         }
823         strbuf_release(&buf);
824         return ret;
825 }
826
827 static void set_common_push_options(struct transport *transport,
828                                    const char *name, int flags)
829 {
830         if (flags & TRANSPORT_PUSH_DRY_RUN) {
831                 if (set_helper_option(transport, "dry-run", "true") != 0)
832                         die(_("helper %s does not support dry-run"), name);
833         } else if (flags & TRANSPORT_PUSH_CERT_ALWAYS) {
834                 if (set_helper_option(transport, TRANS_OPT_PUSH_CERT, "true") != 0)
835                         die(_("helper %s does not support --signed"), name);
836         } else if (flags & TRANSPORT_PUSH_CERT_IF_ASKED) {
837                 if (set_helper_option(transport, TRANS_OPT_PUSH_CERT, "if-asked") != 0)
838                         die(_("helper %s does not support --signed=if-asked"), name);
839         }
840
841         if (flags & TRANSPORT_PUSH_OPTIONS) {
842                 struct string_list_item *item;
843                 for_each_string_list_item(item, transport->push_options)
844                         if (set_helper_option(transport, "push-option", item->string) != 0)
845                                 die(_("helper %s does not support 'push-option'"), name);
846         }
847 }
848
849 static int push_refs_with_push(struct transport *transport,
850                                struct ref *remote_refs, int flags)
851 {
852         int force_all = flags & TRANSPORT_PUSH_FORCE;
853         int mirror = flags & TRANSPORT_PUSH_MIRROR;
854         struct helper_data *data = transport->data;
855         struct strbuf buf = STRBUF_INIT;
856         struct ref *ref;
857         struct string_list cas_options = STRING_LIST_INIT_DUP;
858         struct string_list_item *cas_option;
859
860         get_helper(transport);
861         if (!data->push)
862                 return 1;
863
864         for (ref = remote_refs; ref; ref = ref->next) {
865                 if (!ref->peer_ref && !mirror)
866                         continue;
867
868                 /* Check for statuses set by set_ref_status_for_push() */
869                 switch (ref->status) {
870                 case REF_STATUS_REJECT_NONFASTFORWARD:
871                 case REF_STATUS_REJECT_STALE:
872                 case REF_STATUS_REJECT_ALREADY_EXISTS:
873                 case REF_STATUS_UPTODATE:
874                         continue;
875                 default:
876                         ; /* do nothing */
877                 }
878
879                 if (force_all)
880                         ref->force = 1;
881
882                 strbuf_addstr(&buf, "push ");
883                 if (!ref->deletion) {
884                         if (ref->force)
885                                 strbuf_addch(&buf, '+');
886                         if (ref->peer_ref)
887                                 strbuf_addstr(&buf, ref->peer_ref->name);
888                         else
889                                 strbuf_addstr(&buf, oid_to_hex(&ref->new_oid));
890                 }
891                 strbuf_addch(&buf, ':');
892                 strbuf_addstr(&buf, ref->name);
893                 strbuf_addch(&buf, '\n');
894
895                 /*
896                  * The "--force-with-lease" options without explicit
897                  * values to expect have already been expanded into
898                  * the ref->old_oid_expect[] field; we can ignore
899                  * transport->smart_options->cas altogether and instead
900                  * can enumerate them from the refs.
901                  */
902                 if (ref->expect_old_sha1) {
903                         struct strbuf cas = STRBUF_INIT;
904                         strbuf_addf(&cas, "%s:%s",
905                                     ref->name, oid_to_hex(&ref->old_oid_expect));
906                         string_list_append_nodup(&cas_options,
907                                                  strbuf_detach(&cas, NULL));
908                 }
909         }
910         if (buf.len == 0) {
911                 string_list_clear(&cas_options, 0);
912                 return 0;
913         }
914
915         for_each_string_list_item(cas_option, &cas_options)
916                 set_helper_option(transport, "cas", cas_option->string);
917         set_common_push_options(transport, data->name, flags);
918
919         strbuf_addch(&buf, '\n');
920         sendline(data, &buf);
921         strbuf_release(&buf);
922         string_list_clear(&cas_options, 0);
923
924         return push_update_refs_status(data, remote_refs, flags);
925 }
926
927 static int push_refs_with_export(struct transport *transport,
928                 struct ref *remote_refs, int flags)
929 {
930         struct ref *ref;
931         struct child_process *helper, exporter;
932         struct helper_data *data = transport->data;
933         struct string_list revlist_args = STRING_LIST_INIT_DUP;
934         struct strbuf buf = STRBUF_INIT;
935
936         if (!data->rs.nr)
937                 die(_("remote-helper doesn't support push; refspec needed"));
938
939         set_common_push_options(transport, data->name, flags);
940         if (flags & TRANSPORT_PUSH_FORCE) {
941                 if (set_helper_option(transport, "force", "true") != 0)
942                         warning(_("helper %s does not support 'force'"), data->name);
943         }
944
945         helper = get_helper(transport);
946
947         write_constant(helper->in, "export\n");
948
949         for (ref = remote_refs; ref; ref = ref->next) {
950                 char *private;
951                 struct object_id oid;
952
953                 private = apply_refspecs(&data->rs, ref->name);
954                 if (private && !get_oid(private, &oid)) {
955                         strbuf_addf(&buf, "^%s", private);
956                         string_list_append_nodup(&revlist_args,
957                                                  strbuf_detach(&buf, NULL));
958                         oidcpy(&ref->old_oid, &oid);
959                 }
960                 free(private);
961
962                 if (ref->peer_ref) {
963                         if (strcmp(ref->name, ref->peer_ref->name)) {
964                                 if (!ref->deletion) {
965                                         const char *name;
966                                         int flag;
967
968                                         /* Follow symbolic refs (mainly for HEAD). */
969                                         name = resolve_ref_unsafe(ref->peer_ref->name,
970                                                                   RESOLVE_REF_READING,
971                                                                   &oid, &flag);
972                                         if (!name || !(flag & REF_ISSYMREF))
973                                                 name = ref->peer_ref->name;
974
975                                         strbuf_addf(&buf, "%s:%s", name, ref->name);
976                                 } else
977                                         strbuf_addf(&buf, ":%s", ref->name);
978
979                                 string_list_append(&revlist_args, "--refspec");
980                                 string_list_append(&revlist_args, buf.buf);
981                                 strbuf_release(&buf);
982                         }
983                         if (!ref->deletion)
984                                 string_list_append(&revlist_args, ref->peer_ref->name);
985                 }
986         }
987
988         if (get_exporter(transport, &exporter, &revlist_args))
989                 die(_("couldn't run fast-export"));
990
991         string_list_clear(&revlist_args, 1);
992
993         if (finish_command(&exporter))
994                 die(_("error while running fast-export"));
995         if (push_update_refs_status(data, remote_refs, flags))
996                 return 1;
997
998         if (data->export_marks) {
999                 strbuf_addf(&buf, "%s.tmp", data->export_marks);
1000                 rename(buf.buf, data->export_marks);
1001                 strbuf_release(&buf);
1002         }
1003
1004         return 0;
1005 }
1006
1007 static int push_refs(struct transport *transport,
1008                 struct ref *remote_refs, int flags)
1009 {
1010         struct helper_data *data = transport->data;
1011
1012         if (process_connect(transport, 1)) {
1013                 do_take_over(transport);
1014                 return transport->vtable->push_refs(transport, remote_refs, flags);
1015         }
1016
1017         if (!remote_refs) {
1018                 fprintf(stderr,
1019                         _("No refs in common and none specified; doing nothing.\n"
1020                           "Perhaps you should specify a branch such as 'master'.\n"));
1021                 return 0;
1022         }
1023
1024         if (data->push)
1025                 return push_refs_with_push(transport, remote_refs, flags);
1026
1027         if (data->export)
1028                 return push_refs_with_export(transport, remote_refs, flags);
1029
1030         return -1;
1031 }
1032
1033
1034 static int has_attribute(const char *attrs, const char *attr)
1035 {
1036         int len;
1037         if (!attrs)
1038                 return 0;
1039
1040         len = strlen(attr);
1041         for (;;) {
1042                 const char *space = strchrnul(attrs, ' ');
1043                 if (len == space - attrs && !strncmp(attrs, attr, len))
1044                         return 1;
1045                 if (!*space)
1046                         return 0;
1047                 attrs = space + 1;
1048         }
1049 }
1050
1051 static struct ref *get_refs_list(struct transport *transport, int for_push,
1052                                  const struct argv_array *ref_prefixes)
1053 {
1054         struct helper_data *data = transport->data;
1055         struct child_process *helper;
1056         struct ref *ret = NULL;
1057         struct ref **tail = &ret;
1058         struct ref *posn;
1059         struct strbuf buf = STRBUF_INIT;
1060
1061         helper = get_helper(transport);
1062
1063         if (process_connect(transport, for_push)) {
1064                 do_take_over(transport);
1065                 return transport->vtable->get_refs_list(transport, for_push, ref_prefixes);
1066         }
1067
1068         if (data->push && for_push)
1069                 write_str_in_full(helper->in, "list for-push\n");
1070         else
1071                 write_str_in_full(helper->in, "list\n");
1072
1073         while (1) {
1074                 char *eov, *eon;
1075                 if (recvline(data, &buf))
1076                         exit(128);
1077
1078                 if (!*buf.buf)
1079                         break;
1080
1081                 eov = strchr(buf.buf, ' ');
1082                 if (!eov)
1083                         die(_("malformed response in ref list: %s"), buf.buf);
1084                 eon = strchr(eov + 1, ' ');
1085                 *eov = '\0';
1086                 if (eon)
1087                         *eon = '\0';
1088                 *tail = alloc_ref(eov + 1);
1089                 if (buf.buf[0] == '@')
1090                         (*tail)->symref = xstrdup(buf.buf + 1);
1091                 else if (buf.buf[0] != '?')
1092                         get_oid_hex(buf.buf, &(*tail)->old_oid);
1093                 if (eon) {
1094                         if (has_attribute(eon + 1, "unchanged")) {
1095                                 (*tail)->status |= REF_STATUS_UPTODATE;
1096                                 if (read_ref((*tail)->name, &(*tail)->old_oid) < 0)
1097                                         die(_("could not read ref %s"),
1098                                             (*tail)->name);
1099                         }
1100                 }
1101                 tail = &((*tail)->next);
1102         }
1103         if (debug)
1104                 fprintf(stderr, "Debug: Read ref listing.\n");
1105         strbuf_release(&buf);
1106
1107         for (posn = ret; posn; posn = posn->next)
1108                 resolve_remote_symref(posn, ret);
1109
1110         return ret;
1111 }
1112
1113 static struct transport_vtable vtable = {
1114         0,
1115         set_helper_option,
1116         get_refs_list,
1117         fetch,
1118         push_refs,
1119         connect_helper,
1120         release_helper
1121 };
1122
1123 int transport_helper_init(struct transport *transport, const char *name)
1124 {
1125         struct helper_data *data = xcalloc(1, sizeof(*data));
1126         data->name = name;
1127
1128         transport_check_allowed(name);
1129
1130         if (getenv("GIT_TRANSPORT_HELPER_DEBUG"))
1131                 debug = 1;
1132
1133         transport->data = data;
1134         transport->vtable = &vtable;
1135         transport->smart_options = &(data->transport_options);
1136         return 0;
1137 }
1138
1139 /*
1140  * Linux pipes can buffer 65536 bytes at once (and most platforms can
1141  * buffer less), so attempt reads and writes with up to that size.
1142  */
1143 #define BUFFERSIZE 65536
1144 /* This should be enough to hold debugging message. */
1145 #define PBUFFERSIZE 8192
1146
1147 /* Print bidirectional transfer loop debug message. */
1148 __attribute__((format (printf, 1, 2)))
1149 static void transfer_debug(const char *fmt, ...)
1150 {
1151         /*
1152          * NEEDSWORK: This function is sometimes used from multiple threads, and
1153          * we end up using debug_enabled racily. That "should not matter" since
1154          * we always write the same value, but it's still wrong. This function
1155          * is listed in .tsan-suppressions for the time being.
1156          */
1157
1158         va_list args;
1159         char msgbuf[PBUFFERSIZE];
1160         static int debug_enabled = -1;
1161
1162         if (debug_enabled < 0)
1163                 debug_enabled = getenv("GIT_TRANSLOOP_DEBUG") ? 1 : 0;
1164         if (!debug_enabled)
1165                 return;
1166
1167         va_start(args, fmt);
1168         vsnprintf(msgbuf, PBUFFERSIZE, fmt, args);
1169         va_end(args);
1170         fprintf(stderr, "Transfer loop debugging: %s\n", msgbuf);
1171 }
1172
1173 /* Stream state: More data may be coming in this direction. */
1174 #define SSTATE_TRANSFERRING 0
1175 /*
1176  * Stream state: No more data coming in this direction, flushing rest of
1177  * data.
1178  */
1179 #define SSTATE_FLUSHING 1
1180 /* Stream state: Transfer in this direction finished. */
1181 #define SSTATE_FINISHED 2
1182
1183 #define STATE_NEEDS_READING(state) ((state) <= SSTATE_TRANSFERRING)
1184 #define STATE_NEEDS_WRITING(state) ((state) <= SSTATE_FLUSHING)
1185 #define STATE_NEEDS_CLOSING(state) ((state) == SSTATE_FLUSHING)
1186
1187 /* Unidirectional transfer. */
1188 struct unidirectional_transfer {
1189         /* Source */
1190         int src;
1191         /* Destination */
1192         int dest;
1193         /* Is source socket? */
1194         int src_is_sock;
1195         /* Is destination socket? */
1196         int dest_is_sock;
1197         /* Transfer state (TRANSFERRING/FLUSHING/FINISHED) */
1198         int state;
1199         /* Buffer. */
1200         char buf[BUFFERSIZE];
1201         /* Buffer used. */
1202         size_t bufuse;
1203         /* Name of source. */
1204         const char *src_name;
1205         /* Name of destination. */
1206         const char *dest_name;
1207 };
1208
1209 /* Closes the target (for writing) if transfer has finished. */
1210 static void udt_close_if_finished(struct unidirectional_transfer *t)
1211 {
1212         if (STATE_NEEDS_CLOSING(t->state) && !t->bufuse) {
1213                 t->state = SSTATE_FINISHED;
1214                 if (t->dest_is_sock)
1215                         shutdown(t->dest, SHUT_WR);
1216                 else
1217                         close(t->dest);
1218                 transfer_debug("Closed %s.", t->dest_name);
1219         }
1220 }
1221
1222 /*
1223  * Tries to read data from source into buffer. If buffer is full,
1224  * no data is read. Returns 0 on success, -1 on error.
1225  */
1226 static int udt_do_read(struct unidirectional_transfer *t)
1227 {
1228         ssize_t bytes;
1229
1230         if (t->bufuse == BUFFERSIZE)
1231                 return 0;       /* No space for more. */
1232
1233         transfer_debug("%s is readable", t->src_name);
1234         bytes = xread(t->src, t->buf + t->bufuse, BUFFERSIZE - t->bufuse);
1235         if (bytes < 0) {
1236                 error_errno(_("read(%s) failed"), t->src_name);
1237                 return -1;
1238         } else if (bytes == 0) {
1239                 transfer_debug("%s EOF (with %i bytes in buffer)",
1240                         t->src_name, (int)t->bufuse);
1241                 t->state = SSTATE_FLUSHING;
1242         } else if (bytes > 0) {
1243                 t->bufuse += bytes;
1244                 transfer_debug("Read %i bytes from %s (buffer now at %i)",
1245                         (int)bytes, t->src_name, (int)t->bufuse);
1246         }
1247         return 0;
1248 }
1249
1250 /* Tries to write data from buffer into destination. If buffer is empty,
1251  * no data is written. Returns 0 on success, -1 on error.
1252  */
1253 static int udt_do_write(struct unidirectional_transfer *t)
1254 {
1255         ssize_t bytes;
1256
1257         if (t->bufuse == 0)
1258                 return 0;       /* Nothing to write. */
1259
1260         transfer_debug("%s is writable", t->dest_name);
1261         bytes = xwrite(t->dest, t->buf, t->bufuse);
1262         if (bytes < 0) {
1263                 error_errno(_("write(%s) failed"), t->dest_name);
1264                 return -1;
1265         } else if (bytes > 0) {
1266                 t->bufuse -= bytes;
1267                 if (t->bufuse)
1268                         memmove(t->buf, t->buf + bytes, t->bufuse);
1269                 transfer_debug("Wrote %i bytes to %s (buffer now at %i)",
1270                         (int)bytes, t->dest_name, (int)t->bufuse);
1271         }
1272         return 0;
1273 }
1274
1275
1276 /* State of bidirectional transfer loop. */
1277 struct bidirectional_transfer_state {
1278         /* Direction from program to git. */
1279         struct unidirectional_transfer ptg;
1280         /* Direction from git to program. */
1281         struct unidirectional_transfer gtp;
1282 };
1283
1284 static void *udt_copy_task_routine(void *udt)
1285 {
1286         struct unidirectional_transfer *t = (struct unidirectional_transfer *)udt;
1287         while (t->state != SSTATE_FINISHED) {
1288                 if (STATE_NEEDS_READING(t->state))
1289                         if (udt_do_read(t))
1290                                 return NULL;
1291                 if (STATE_NEEDS_WRITING(t->state))
1292                         if (udt_do_write(t))
1293                                 return NULL;
1294                 if (STATE_NEEDS_CLOSING(t->state))
1295                         udt_close_if_finished(t);
1296         }
1297         return udt;     /* Just some non-NULL value. */
1298 }
1299
1300 #ifndef NO_PTHREADS
1301
1302 /*
1303  * Join thread, with appropriate errors on failure. Name is name for the
1304  * thread (for error messages). Returns 0 on success, 1 on failure.
1305  */
1306 static int tloop_join(pthread_t thread, const char *name)
1307 {
1308         int err;
1309         void *tret;
1310         err = pthread_join(thread, &tret);
1311         if (!tret) {
1312                 error(_("%s thread failed"), name);
1313                 return 1;
1314         }
1315         if (err) {
1316                 error(_("%s thread failed to join: %s"), name, strerror(err));
1317                 return 1;
1318         }
1319         return 0;
1320 }
1321
1322 /*
1323  * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1324  * -1 on failure.
1325  */
1326 static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1327 {
1328         pthread_t gtp_thread;
1329         pthread_t ptg_thread;
1330         int err;
1331         int ret = 0;
1332         err = pthread_create(&gtp_thread, NULL, udt_copy_task_routine,
1333                 &s->gtp);
1334         if (err)
1335                 die(_("can't start thread for copying data: %s"), strerror(err));
1336         err = pthread_create(&ptg_thread, NULL, udt_copy_task_routine,
1337                 &s->ptg);
1338         if (err)
1339                 die(_("can't start thread for copying data: %s"), strerror(err));
1340
1341         ret |= tloop_join(gtp_thread, "Git to program copy");
1342         ret |= tloop_join(ptg_thread, "Program to git copy");
1343         return ret;
1344 }
1345 #else
1346
1347 /* Close the source and target (for writing) for transfer. */
1348 static void udt_kill_transfer(struct unidirectional_transfer *t)
1349 {
1350         t->state = SSTATE_FINISHED;
1351         /*
1352          * Socket read end left open isn't a disaster if nobody
1353          * attempts to read from it (mingw compat headers do not
1354          * have SHUT_RD)...
1355          *
1356          * We can't fully close the socket since otherwise gtp
1357          * task would first close the socket it sends data to
1358          * while closing the ptg file descriptors.
1359          */
1360         if (!t->src_is_sock)
1361                 close(t->src);
1362         if (t->dest_is_sock)
1363                 shutdown(t->dest, SHUT_WR);
1364         else
1365                 close(t->dest);
1366 }
1367
1368 /*
1369  * Join process, with appropriate errors on failure. Name is name for the
1370  * process (for error messages). Returns 0 on success, 1 on failure.
1371  */
1372 static int tloop_join(pid_t pid, const char *name)
1373 {
1374         int tret;
1375         if (waitpid(pid, &tret, 0) < 0) {
1376                 error_errno(_("%s process failed to wait"), name);
1377                 return 1;
1378         }
1379         if (!WIFEXITED(tret) || WEXITSTATUS(tret)) {
1380                 error(_("%s process failed"), name);
1381                 return 1;
1382         }
1383         return 0;
1384 }
1385
1386 /*
1387  * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1388  * -1 on failure.
1389  */
1390 static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1391 {
1392         pid_t pid1, pid2;
1393         int ret = 0;
1394
1395         /* Fork thread #1: git to program. */
1396         pid1 = fork();
1397         if (pid1 < 0)
1398                 die_errno(_("can't start thread for copying data"));
1399         else if (pid1 == 0) {
1400                 udt_kill_transfer(&s->ptg);
1401                 exit(udt_copy_task_routine(&s->gtp) ? 0 : 1);
1402         }
1403
1404         /* Fork thread #2: program to git. */
1405         pid2 = fork();
1406         if (pid2 < 0)
1407                 die_errno(_("can't start thread for copying data"));
1408         else if (pid2 == 0) {
1409                 udt_kill_transfer(&s->gtp);
1410                 exit(udt_copy_task_routine(&s->ptg) ? 0 : 1);
1411         }
1412
1413         /*
1414          * Close both streams in parent as to not interfere with
1415          * end of file detection and wait for both tasks to finish.
1416          */
1417         udt_kill_transfer(&s->gtp);
1418         udt_kill_transfer(&s->ptg);
1419         ret |= tloop_join(pid1, "Git to program copy");
1420         ret |= tloop_join(pid2, "Program to git copy");
1421         return ret;
1422 }
1423 #endif
1424
1425 /*
1426  * Copies data from stdin to output and from input to stdout simultaneously.
1427  * Additionally filtering through given filter. If filter is NULL, uses
1428  * identity filter.
1429  */
1430 int bidirectional_transfer_loop(int input, int output)
1431 {
1432         struct bidirectional_transfer_state state;
1433
1434         /* Fill the state fields. */
1435         state.ptg.src = input;
1436         state.ptg.dest = 1;
1437         state.ptg.src_is_sock = (input == output);
1438         state.ptg.dest_is_sock = 0;
1439         state.ptg.state = SSTATE_TRANSFERRING;
1440         state.ptg.bufuse = 0;
1441         state.ptg.src_name = "remote input";
1442         state.ptg.dest_name = "stdout";
1443
1444         state.gtp.src = 0;
1445         state.gtp.dest = output;
1446         state.gtp.src_is_sock = 0;
1447         state.gtp.dest_is_sock = (input == output);
1448         state.gtp.state = SSTATE_TRANSFERRING;
1449         state.gtp.bufuse = 0;
1450         state.gtp.src_name = "stdin";
1451         state.gtp.dest_name = "remote output";
1452
1453         return tloop_spawnwait_tasks(&state);
1454 }