submodule: Use cat instead of echo to avoid DOS line-endings
[git/dscho.git] / transport-helper.c
blob6f227e253bf638de37ce74347213657c23185afa
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 "quote.h"
9 #include "remote.h"
10 #include "string-list.h"
11 #include "thread-utils.h"
13 static int debug;
15 struct helper_data {
16 const char *name;
17 struct child_process *helper;
18 FILE *out;
19 unsigned fetch : 1,
20 import : 1,
21 export : 1,
22 option : 1,
23 push : 1,
24 connect : 1,
25 no_disconnect_req : 1;
26 char *export_marks;
27 char *import_marks;
28 /* These go from remote name (as in "list") to private name */
29 struct refspec *refspecs;
30 int refspec_nr;
31 /* Transport options for fetch-pack/send-pack (should one of
32 * those be invoked).
34 struct git_transport_options transport_options;
37 static void sendline(struct helper_data *helper, struct strbuf *buffer)
39 if (debug)
40 fprintf(stderr, "Debug: Remote helper: -> %s", buffer->buf);
41 if (write_in_full(helper->helper->in, buffer->buf, buffer->len)
42 != buffer->len)
43 die_errno("Full write to remote helper failed");
46 static int recvline_fh(FILE *helper, struct strbuf *buffer)
48 strbuf_reset(buffer);
49 if (debug)
50 fprintf(stderr, "Debug: Remote helper: Waiting...\n");
51 if (strbuf_getline(buffer, helper, '\n') == EOF) {
52 if (debug)
53 fprintf(stderr, "Debug: Remote helper quit.\n");
54 exit(128);
57 if (debug)
58 fprintf(stderr, "Debug: Remote helper: <- %s\n", buffer->buf);
59 return 0;
62 static int recvline(struct helper_data *helper, struct strbuf *buffer)
64 return recvline_fh(helper->out, buffer);
67 static void xchgline(struct helper_data *helper, struct strbuf *buffer)
69 sendline(helper, buffer);
70 recvline(helper, buffer);
73 static void write_constant(int fd, const char *str)
75 if (debug)
76 fprintf(stderr, "Debug: Remote helper: -> %s", str);
77 if (write_in_full(fd, str, strlen(str)) != strlen(str))
78 die_errno("Full write to remote helper failed");
81 static const char *remove_ext_force(const char *url)
83 if (url) {
84 const char *colon = strchr(url, ':');
85 if (colon && colon[1] == ':')
86 return colon + 2;
88 return url;
91 static void do_take_over(struct transport *transport)
93 struct helper_data *data;
94 data = (struct helper_data *)transport->data;
95 transport_take_over(transport, data->helper);
96 fclose(data->out);
97 free(data);
100 static struct child_process *get_helper(struct transport *transport)
102 struct helper_data *data = transport->data;
103 struct strbuf buf = STRBUF_INIT;
104 struct child_process *helper;
105 const char **refspecs = NULL;
106 int refspec_nr = 0;
107 int refspec_alloc = 0;
108 int duped;
109 int code;
110 char git_dir_buf[sizeof(GIT_DIR_ENVIRONMENT) + PATH_MAX + 1];
111 const char *helper_env[] = {
112 git_dir_buf,
113 NULL
117 if (data->helper)
118 return data->helper;
120 helper = xcalloc(1, sizeof(*helper));
121 helper->in = -1;
122 helper->out = -1;
123 helper->err = 0;
124 helper->argv = xcalloc(4, sizeof(*helper->argv));
125 strbuf_addf(&buf, "git-remote-%s", data->name);
126 helper->argv[0] = strbuf_detach(&buf, NULL);
127 helper->argv[1] = transport->remote->name;
128 helper->argv[2] = remove_ext_force(transport->url);
129 helper->git_cmd = 0;
130 helper->silent_exec_failure = 1;
132 snprintf(git_dir_buf, sizeof(git_dir_buf), "%s=%s", GIT_DIR_ENVIRONMENT, get_git_dir());
133 helper->env = helper_env;
135 code = start_command(helper);
136 if (code < 0 && errno == ENOENT)
137 die("Unable to find remote helper for '%s'", data->name);
138 else if (code != 0)
139 exit(code);
141 data->helper = helper;
142 data->no_disconnect_req = 0;
145 * Open the output as FILE* so strbuf_getline() can be used.
146 * Do this with duped fd because fclose() will close the fd,
147 * and stuff like taking over will require the fd to remain.
149 duped = dup(helper->out);
150 if (duped < 0)
151 die_errno("Can't dup helper output fd");
152 data->out = xfdopen(duped, "r");
154 write_constant(helper->in, "capabilities\n");
156 while (1) {
157 const char *capname;
158 int mandatory = 0;
159 recvline(data, &buf);
161 if (!*buf.buf)
162 break;
164 if (*buf.buf == '*') {
165 capname = buf.buf + 1;
166 mandatory = 1;
167 } else
168 capname = buf.buf;
170 if (debug)
171 fprintf(stderr, "Debug: Got cap %s\n", capname);
172 if (!strcmp(capname, "fetch"))
173 data->fetch = 1;
174 else if (!strcmp(capname, "option"))
175 data->option = 1;
176 else if (!strcmp(capname, "push"))
177 data->push = 1;
178 else if (!strcmp(capname, "import"))
179 data->import = 1;
180 else if (!strcmp(capname, "export"))
181 data->export = 1;
182 else if (!data->refspecs && !prefixcmp(capname, "refspec ")) {
183 ALLOC_GROW(refspecs,
184 refspec_nr + 1,
185 refspec_alloc);
186 refspecs[refspec_nr++] = xstrdup(capname + strlen("refspec "));
187 } else if (!strcmp(capname, "connect")) {
188 data->connect = 1;
189 } else if (!prefixcmp(capname, "export-marks ")) {
190 struct strbuf arg = STRBUF_INIT;
191 strbuf_addstr(&arg, "--export-marks=");
192 strbuf_addstr(&arg, capname + strlen("export-marks "));
193 data->export_marks = strbuf_detach(&arg, NULL);
194 } else if (!prefixcmp(capname, "import-marks")) {
195 struct strbuf arg = STRBUF_INIT;
196 strbuf_addstr(&arg, "--import-marks=");
197 strbuf_addstr(&arg, capname + strlen("import-marks "));
198 data->import_marks = strbuf_detach(&arg, NULL);
199 } else if (mandatory) {
200 die("Unknown mandatory capability %s. This remote "
201 "helper probably needs newer version of Git.\n",
202 capname);
205 if (refspecs) {
206 int i;
207 data->refspec_nr = refspec_nr;
208 data->refspecs = parse_fetch_refspec(refspec_nr, refspecs);
209 for (i = 0; i < refspec_nr; i++) {
210 free((char *)refspecs[i]);
212 free(refspecs);
214 strbuf_release(&buf);
215 if (debug)
216 fprintf(stderr, "Debug: Capabilities complete.\n");
217 return data->helper;
220 static int disconnect_helper(struct transport *transport)
222 struct helper_data *data = transport->data;
223 struct strbuf buf = STRBUF_INIT;
224 int res = 0;
226 if (data->helper) {
227 if (debug)
228 fprintf(stderr, "Debug: Disconnecting.\n");
229 if (!data->no_disconnect_req) {
230 strbuf_addf(&buf, "\n");
231 sendline(data, &buf);
233 close(data->helper->in);
234 close(data->helper->out);
235 fclose(data->out);
236 res = finish_command(data->helper);
237 free((char *)data->helper->argv[0]);
238 free(data->helper->argv);
239 free(data->helper);
240 data->helper = NULL;
242 return res;
245 static const char *unsupported_options[] = {
246 TRANS_OPT_UPLOADPACK,
247 TRANS_OPT_RECEIVEPACK,
248 TRANS_OPT_THIN,
249 TRANS_OPT_KEEP
251 static const char *boolean_options[] = {
252 TRANS_OPT_THIN,
253 TRANS_OPT_KEEP,
254 TRANS_OPT_FOLLOWTAGS
257 static int set_helper_option(struct transport *transport,
258 const char *name, const char *value)
260 struct helper_data *data = transport->data;
261 struct strbuf buf = STRBUF_INIT;
262 int i, ret, is_bool = 0;
264 get_helper(transport);
266 if (!data->option)
267 return 1;
269 for (i = 0; i < ARRAY_SIZE(unsupported_options); i++) {
270 if (!strcmp(name, unsupported_options[i]))
271 return 1;
274 for (i = 0; i < ARRAY_SIZE(boolean_options); i++) {
275 if (!strcmp(name, boolean_options[i])) {
276 is_bool = 1;
277 break;
281 strbuf_addf(&buf, "option %s ", name);
282 if (is_bool)
283 strbuf_addstr(&buf, value ? "true" : "false");
284 else
285 quote_c_style(value, &buf, NULL, 0);
286 strbuf_addch(&buf, '\n');
288 xchgline(data, &buf);
290 if (!strcmp(buf.buf, "ok"))
291 ret = 0;
292 else if (!prefixcmp(buf.buf, "error")) {
293 ret = -1;
294 } else if (!strcmp(buf.buf, "unsupported"))
295 ret = 1;
296 else {
297 warning("%s unexpectedly said: '%s'", data->name, buf.buf);
298 ret = 1;
300 strbuf_release(&buf);
301 return ret;
304 static void standard_options(struct transport *t)
306 char buf[16];
307 int n;
308 int v = t->verbose;
310 set_helper_option(t, "progress", t->progress ? "true" : "false");
312 n = snprintf(buf, sizeof(buf), "%d", v + 1);
313 if (n >= sizeof(buf))
314 die("impossibly large verbosity value");
315 set_helper_option(t, "verbosity", buf);
318 static int release_helper(struct transport *transport)
320 int res = 0;
321 struct helper_data *data = transport->data;
322 free_refspec(data->refspec_nr, data->refspecs);
323 data->refspecs = NULL;
324 res = disconnect_helper(transport);
325 free(transport->data);
326 return res;
329 static int fetch_with_fetch(struct transport *transport,
330 int nr_heads, struct ref **to_fetch)
332 struct helper_data *data = transport->data;
333 int i;
334 struct strbuf buf = STRBUF_INIT;
336 standard_options(transport);
338 for (i = 0; i < nr_heads; i++) {
339 const struct ref *posn = to_fetch[i];
340 if (posn->status & REF_STATUS_UPTODATE)
341 continue;
343 strbuf_addf(&buf, "fetch %s %s\n",
344 sha1_to_hex(posn->old_sha1), posn->name);
347 strbuf_addch(&buf, '\n');
348 sendline(data, &buf);
350 while (1) {
351 recvline(data, &buf);
353 if (!prefixcmp(buf.buf, "lock ")) {
354 const char *name = buf.buf + 5;
355 if (transport->pack_lockfile)
356 warning("%s also locked %s", data->name, name);
357 else
358 transport->pack_lockfile = xstrdup(name);
360 else if (!buf.len)
361 break;
362 else
363 warning("%s unexpectedly said: '%s'", data->name, buf.buf);
365 strbuf_release(&buf);
366 return 0;
369 static int get_importer(struct transport *transport, struct child_process *fastimport)
371 struct child_process *helper = get_helper(transport);
372 memset(fastimport, 0, sizeof(*fastimport));
373 fastimport->in = helper->out;
374 fastimport->argv = xcalloc(5, sizeof(*fastimport->argv));
375 fastimport->argv[0] = "fast-import";
376 fastimport->argv[1] = "--quiet";
378 fastimport->git_cmd = 1;
379 return start_command(fastimport);
382 static int get_exporter(struct transport *transport,
383 struct child_process *fastexport,
384 struct string_list *revlist_args)
386 struct helper_data *data = transport->data;
387 struct child_process *helper = get_helper(transport);
388 int argc = 0, i;
389 memset(fastexport, 0, sizeof(*fastexport));
391 /* we need to duplicate helper->in because we want to use it after
392 * fastexport is done with it. */
393 fastexport->out = dup(helper->in);
394 fastexport->argv = xcalloc(5 + revlist_args->nr, sizeof(*fastexport->argv));
395 fastexport->argv[argc++] = "fast-export";
396 fastexport->argv[argc++] = "--use-done-feature";
397 if (data->export_marks)
398 fastexport->argv[argc++] = data->export_marks;
399 if (data->import_marks)
400 fastexport->argv[argc++] = data->import_marks;
402 for (i = 0; i < revlist_args->nr; i++)
403 fastexport->argv[argc++] = revlist_args->items[i].string;
405 fastexport->git_cmd = 1;
406 return start_command(fastexport);
409 static int fetch_with_import(struct transport *transport,
410 int nr_heads, struct ref **to_fetch)
412 struct child_process fastimport;
413 struct helper_data *data = transport->data;
414 int i;
415 struct ref *posn;
416 struct strbuf buf = STRBUF_INIT;
418 get_helper(transport);
420 if (get_importer(transport, &fastimport))
421 die("Couldn't run fast-import");
423 for (i = 0; i < nr_heads; i++) {
424 posn = to_fetch[i];
425 if (posn->status & REF_STATUS_UPTODATE)
426 continue;
428 strbuf_addf(&buf, "import %s\n", posn->name);
429 sendline(data, &buf);
430 strbuf_reset(&buf);
433 write_constant(data->helper->in, "\n");
435 if (finish_command(&fastimport))
436 die("Error while running fast-import");
437 free(fastimport.argv);
438 fastimport.argv = NULL;
440 for (i = 0; i < nr_heads; i++) {
441 char *private;
442 posn = to_fetch[i];
443 if (posn->status & REF_STATUS_UPTODATE)
444 continue;
445 if (data->refspecs)
446 private = apply_refspecs(data->refspecs, data->refspec_nr, posn->name);
447 else
448 private = xstrdup(posn->name);
449 if (private) {
450 read_ref(private, posn->old_sha1);
451 free(private);
454 strbuf_release(&buf);
455 return 0;
458 static int process_connect_service(struct transport *transport,
459 const char *name, const char *exec)
461 struct helper_data *data = transport->data;
462 struct strbuf cmdbuf = STRBUF_INIT;
463 struct child_process *helper;
464 int r, duped, ret = 0;
465 FILE *input;
467 helper = get_helper(transport);
470 * Yes, dup the pipe another time, as we need unbuffered version
471 * of input pipe as FILE*. fclose() closes the underlying fd and
472 * stream buffering only can be changed before first I/O operation
473 * on it.
475 duped = dup(helper->out);
476 if (duped < 0)
477 die_errno("Can't dup helper output fd");
478 input = xfdopen(duped, "r");
479 setvbuf(input, NULL, _IONBF, 0);
482 * Handle --upload-pack and friends. This is fire and forget...
483 * just warn if it fails.
485 if (strcmp(name, exec)) {
486 r = set_helper_option(transport, "servpath", exec);
487 if (r > 0)
488 warning("Setting remote service path not supported by protocol.");
489 else if (r < 0)
490 warning("Invalid remote service path.");
493 if (data->connect)
494 strbuf_addf(&cmdbuf, "connect %s\n", name);
495 else
496 goto exit;
498 sendline(data, &cmdbuf);
499 recvline_fh(input, &cmdbuf);
500 if (!strcmp(cmdbuf.buf, "")) {
501 data->no_disconnect_req = 1;
502 if (debug)
503 fprintf(stderr, "Debug: Smart transport connection "
504 "ready.\n");
505 ret = 1;
506 } else if (!strcmp(cmdbuf.buf, "fallback")) {
507 if (debug)
508 fprintf(stderr, "Debug: Falling back to dumb "
509 "transport.\n");
510 } else
511 die("Unknown response to connect: %s",
512 cmdbuf.buf);
514 exit:
515 fclose(input);
516 return ret;
519 static int process_connect(struct transport *transport,
520 int for_push)
522 struct helper_data *data = transport->data;
523 const char *name;
524 const char *exec;
526 name = for_push ? "git-receive-pack" : "git-upload-pack";
527 if (for_push)
528 exec = data->transport_options.receivepack;
529 else
530 exec = data->transport_options.uploadpack;
532 return process_connect_service(transport, name, exec);
535 static int connect_helper(struct transport *transport, const char *name,
536 const char *exec, int fd[2])
538 struct helper_data *data = transport->data;
540 /* Get_helper so connect is inited. */
541 get_helper(transport);
542 if (!data->connect)
543 die("Operation not supported by protocol.");
545 if (!process_connect_service(transport, name, exec))
546 die("Can't connect to subservice %s.", name);
548 fd[0] = data->helper->out;
549 fd[1] = data->helper->in;
550 return 0;
553 static int fetch(struct transport *transport,
554 int nr_heads, struct ref **to_fetch)
556 struct helper_data *data = transport->data;
557 int i, count;
559 if (process_connect(transport, 0)) {
560 do_take_over(transport);
561 return transport->fetch(transport, nr_heads, to_fetch);
564 count = 0;
565 for (i = 0; i < nr_heads; i++)
566 if (!(to_fetch[i]->status & REF_STATUS_UPTODATE))
567 count++;
569 if (!count)
570 return 0;
572 if (data->fetch)
573 return fetch_with_fetch(transport, nr_heads, to_fetch);
575 if (data->import)
576 return fetch_with_import(transport, nr_heads, to_fetch);
578 return -1;
581 static void push_update_ref_status(struct strbuf *buf,
582 struct ref **ref,
583 struct ref *remote_refs)
585 char *refname, *msg;
586 int status;
588 if (!prefixcmp(buf->buf, "ok ")) {
589 status = REF_STATUS_OK;
590 refname = buf->buf + 3;
591 } else if (!prefixcmp(buf->buf, "error ")) {
592 status = REF_STATUS_REMOTE_REJECT;
593 refname = buf->buf + 6;
594 } else
595 die("expected ok/error, helper said '%s'\n", buf->buf);
597 msg = strchr(refname, ' ');
598 if (msg) {
599 struct strbuf msg_buf = STRBUF_INIT;
600 const char *end;
602 *msg++ = '\0';
603 if (!unquote_c_style(&msg_buf, msg, &end))
604 msg = strbuf_detach(&msg_buf, NULL);
605 else
606 msg = xstrdup(msg);
607 strbuf_release(&msg_buf);
609 if (!strcmp(msg, "no match")) {
610 status = REF_STATUS_NONE;
611 free(msg);
612 msg = NULL;
614 else if (!strcmp(msg, "up to date")) {
615 status = REF_STATUS_UPTODATE;
616 free(msg);
617 msg = NULL;
619 else if (!strcmp(msg, "non-fast forward")) {
620 status = REF_STATUS_REJECT_NONFASTFORWARD;
621 free(msg);
622 msg = NULL;
626 if (*ref)
627 *ref = find_ref_by_name(*ref, refname);
628 if (!*ref)
629 *ref = find_ref_by_name(remote_refs, refname);
630 if (!*ref) {
631 warning("helper reported unexpected status of %s", refname);
632 return;
635 if ((*ref)->status != REF_STATUS_NONE) {
637 * Earlier, the ref was marked not to be pushed, so ignore the ref
638 * status reported by the remote helper if the latter is 'no match'.
640 if (status == REF_STATUS_NONE)
641 return;
644 (*ref)->status = status;
645 (*ref)->remote_status = msg;
648 static void push_update_refs_status(struct helper_data *data,
649 struct ref *remote_refs)
651 struct strbuf buf = STRBUF_INIT;
652 struct ref *ref = remote_refs;
653 for (;;) {
654 recvline(data, &buf);
655 if (!buf.len)
656 break;
658 push_update_ref_status(&buf, &ref, remote_refs);
660 strbuf_release(&buf);
663 static int push_refs_with_push(struct transport *transport,
664 struct ref *remote_refs, int flags)
666 int force_all = flags & TRANSPORT_PUSH_FORCE;
667 int mirror = flags & TRANSPORT_PUSH_MIRROR;
668 struct helper_data *data = transport->data;
669 struct strbuf buf = STRBUF_INIT;
670 struct ref *ref;
672 get_helper(transport);
673 if (!data->push)
674 return 1;
676 for (ref = remote_refs; ref; ref = ref->next) {
677 if (!ref->peer_ref && !mirror)
678 continue;
680 /* Check for statuses set by set_ref_status_for_push() */
681 switch (ref->status) {
682 case REF_STATUS_REJECT_NONFASTFORWARD:
683 case REF_STATUS_UPTODATE:
684 continue;
685 default:
686 ; /* do nothing */
689 if (force_all)
690 ref->force = 1;
692 strbuf_addstr(&buf, "push ");
693 if (!ref->deletion) {
694 if (ref->force)
695 strbuf_addch(&buf, '+');
696 if (ref->peer_ref)
697 strbuf_addstr(&buf, ref->peer_ref->name);
698 else
699 strbuf_addstr(&buf, sha1_to_hex(ref->new_sha1));
701 strbuf_addch(&buf, ':');
702 strbuf_addstr(&buf, ref->name);
703 strbuf_addch(&buf, '\n');
705 if (buf.len == 0)
706 return 0;
708 standard_options(transport);
710 if (flags & TRANSPORT_PUSH_DRY_RUN) {
711 if (set_helper_option(transport, "dry-run", "true") != 0)
712 die("helper %s does not support dry-run", data->name);
715 strbuf_addch(&buf, '\n');
716 sendline(data, &buf);
717 strbuf_release(&buf);
719 push_update_refs_status(data, remote_refs);
720 return 0;
723 static int push_refs_with_export(struct transport *transport,
724 struct ref *remote_refs, int flags)
726 struct ref *ref;
727 struct child_process *helper, exporter;
728 struct helper_data *data = transport->data;
729 struct string_list revlist_args = STRING_LIST_INIT_NODUP;
730 struct strbuf buf = STRBUF_INIT;
732 helper = get_helper(transport);
734 write_constant(helper->in, "export\n");
736 strbuf_reset(&buf);
738 for (ref = remote_refs; ref; ref = ref->next) {
739 char *private;
740 unsigned char sha1[20];
742 if (!data->refspecs)
743 continue;
744 private = apply_refspecs(data->refspecs, data->refspec_nr, ref->name);
745 if (private && !get_sha1(private, sha1)) {
746 strbuf_addf(&buf, "^%s", private);
747 string_list_append(&revlist_args, strbuf_detach(&buf, NULL));
749 free(private);
751 if (ref->deletion) {
752 die("remote-helpers do not support ref deletion");
755 if (ref->peer_ref)
756 string_list_append(&revlist_args, ref->peer_ref->name);
760 if (get_exporter(transport, &exporter, &revlist_args))
761 die("Couldn't run fast-export");
763 if (finish_command(&exporter))
764 die("Error while running fast-export");
765 push_update_refs_status(data, remote_refs);
766 return 0;
769 static int push_refs(struct transport *transport,
770 struct ref *remote_refs, int flags)
772 struct helper_data *data = transport->data;
774 if (process_connect(transport, 1)) {
775 do_take_over(transport);
776 return transport->push_refs(transport, remote_refs, flags);
779 if (!remote_refs) {
780 fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
781 "Perhaps you should specify a branch such as 'master'.\n");
782 return 0;
785 if (data->push)
786 return push_refs_with_push(transport, remote_refs, flags);
788 if (data->export)
789 return push_refs_with_export(transport, remote_refs, flags);
791 return -1;
795 static int has_attribute(const char *attrs, const char *attr) {
796 int len;
797 if (!attrs)
798 return 0;
800 len = strlen(attr);
801 for (;;) {
802 const char *space = strchrnul(attrs, ' ');
803 if (len == space - attrs && !strncmp(attrs, attr, len))
804 return 1;
805 if (!*space)
806 return 0;
807 attrs = space + 1;
811 static struct ref *get_refs_list(struct transport *transport, int for_push)
813 struct helper_data *data = transport->data;
814 struct child_process *helper;
815 struct ref *ret = NULL;
816 struct ref **tail = &ret;
817 struct ref *posn;
818 struct strbuf buf = STRBUF_INIT;
820 helper = get_helper(transport);
822 if (process_connect(transport, for_push)) {
823 do_take_over(transport);
824 return transport->get_refs_list(transport, for_push);
827 if (data->push && for_push)
828 write_str_in_full(helper->in, "list for-push\n");
829 else
830 write_str_in_full(helper->in, "list\n");
832 while (1) {
833 char *eov, *eon;
834 recvline(data, &buf);
836 if (!*buf.buf)
837 break;
839 eov = strchr(buf.buf, ' ');
840 if (!eov)
841 die("Malformed response in ref list: %s", buf.buf);
842 eon = strchr(eov + 1, ' ');
843 *eov = '\0';
844 if (eon)
845 *eon = '\0';
846 *tail = alloc_ref(eov + 1);
847 if (buf.buf[0] == '@')
848 (*tail)->symref = xstrdup(buf.buf + 1);
849 else if (buf.buf[0] != '?')
850 get_sha1_hex(buf.buf, (*tail)->old_sha1);
851 if (eon) {
852 if (has_attribute(eon + 1, "unchanged")) {
853 (*tail)->status |= REF_STATUS_UPTODATE;
854 read_ref((*tail)->name, (*tail)->old_sha1);
857 tail = &((*tail)->next);
859 if (debug)
860 fprintf(stderr, "Debug: Read ref listing.\n");
861 strbuf_release(&buf);
863 for (posn = ret; posn; posn = posn->next)
864 resolve_remote_symref(posn, ret);
866 return ret;
869 int transport_helper_init(struct transport *transport, const char *name)
871 struct helper_data *data = xcalloc(sizeof(*data), 1);
872 data->name = name;
874 if (getenv("GIT_TRANSPORT_HELPER_DEBUG"))
875 debug = 1;
877 transport->data = data;
878 transport->set_option = set_helper_option;
879 transport->get_refs_list = get_refs_list;
880 transport->fetch = fetch;
881 transport->push_refs = push_refs;
882 transport->disconnect = release_helper;
883 transport->connect = connect_helper;
884 transport->smart_options = &(data->transport_options);
885 return 0;
889 * Linux pipes can buffer 65536 bytes at once (and most platforms can
890 * buffer less), so attempt reads and writes with up to that size.
892 #define BUFFERSIZE 65536
893 /* This should be enough to hold debugging message. */
894 #define PBUFFERSIZE 8192
896 /* Print bidirectional transfer loop debug message. */
897 static void transfer_debug(const char *fmt, ...)
899 va_list args;
900 char msgbuf[PBUFFERSIZE];
901 static int debug_enabled = -1;
903 if (debug_enabled < 0)
904 debug_enabled = getenv("GIT_TRANSLOOP_DEBUG") ? 1 : 0;
905 if (!debug_enabled)
906 return;
908 va_start(args, fmt);
909 vsnprintf(msgbuf, PBUFFERSIZE, fmt, args);
910 va_end(args);
911 fprintf(stderr, "Transfer loop debugging: %s\n", msgbuf);
914 /* Stream state: More data may be coming in this direction. */
915 #define SSTATE_TRANSFERING 0
917 * Stream state: No more data coming in this direction, flushing rest of
918 * data.
920 #define SSTATE_FLUSHING 1
921 /* Stream state: Transfer in this direction finished. */
922 #define SSTATE_FINISHED 2
924 #define STATE_NEEDS_READING(state) ((state) <= SSTATE_TRANSFERING)
925 #define STATE_NEEDS_WRITING(state) ((state) <= SSTATE_FLUSHING)
926 #define STATE_NEEDS_CLOSING(state) ((state) == SSTATE_FLUSHING)
928 /* Unidirectional transfer. */
929 struct unidirectional_transfer {
930 /* Source */
931 int src;
932 /* Destination */
933 int dest;
934 /* Is source socket? */
935 int src_is_sock;
936 /* Is destination socket? */
937 int dest_is_sock;
938 /* Transfer state (TRANSFERING/FLUSHING/FINISHED) */
939 int state;
940 /* Buffer. */
941 char buf[BUFFERSIZE];
942 /* Buffer used. */
943 size_t bufuse;
944 /* Name of source. */
945 const char *src_name;
946 /* Name of destination. */
947 const char *dest_name;
950 /* Closes the target (for writing) if transfer has finished. */
951 static void udt_close_if_finished(struct unidirectional_transfer *t)
953 if (STATE_NEEDS_CLOSING(t->state) && !t->bufuse) {
954 t->state = SSTATE_FINISHED;
955 if (t->dest_is_sock)
956 shutdown(t->dest, SHUT_WR);
957 else
958 close(t->dest);
959 transfer_debug("Closed %s.", t->dest_name);
964 * Tries to read read data from source into buffer. If buffer is full,
965 * no data is read. Returns 0 on success, -1 on error.
967 static int udt_do_read(struct unidirectional_transfer *t)
969 ssize_t bytes;
971 if (t->bufuse == BUFFERSIZE)
972 return 0; /* No space for more. */
974 transfer_debug("%s is readable", t->src_name);
975 bytes = read(t->src, t->buf + t->bufuse, BUFFERSIZE - t->bufuse);
976 if (bytes < 0 && errno != EWOULDBLOCK && errno != EAGAIN &&
977 errno != EINTR) {
978 error("read(%s) failed: %s", t->src_name, strerror(errno));
979 return -1;
980 } else if (bytes == 0) {
981 transfer_debug("%s EOF (with %i bytes in buffer)",
982 t->src_name, t->bufuse);
983 t->state = SSTATE_FLUSHING;
984 } else if (bytes > 0) {
985 t->bufuse += bytes;
986 transfer_debug("Read %i bytes from %s (buffer now at %i)",
987 (int)bytes, t->src_name, (int)t->bufuse);
989 return 0;
992 /* Tries to write data from buffer into destination. If buffer is empty,
993 * no data is written. Returns 0 on success, -1 on error.
995 static int udt_do_write(struct unidirectional_transfer *t)
997 ssize_t bytes;
999 if (t->bufuse == 0)
1000 return 0; /* Nothing to write. */
1002 transfer_debug("%s is writable", t->dest_name);
1003 bytes = write(t->dest, t->buf, t->bufuse);
1004 if (bytes < 0 && errno != EWOULDBLOCK && errno != EAGAIN &&
1005 errno != EINTR) {
1006 error("write(%s) failed: %s", t->dest_name, strerror(errno));
1007 return -1;
1008 } else if (bytes > 0) {
1009 t->bufuse -= bytes;
1010 if (t->bufuse)
1011 memmove(t->buf, t->buf + bytes, t->bufuse);
1012 transfer_debug("Wrote %i bytes to %s (buffer now at %i)",
1013 (int)bytes, t->dest_name, (int)t->bufuse);
1015 return 0;
1019 /* State of bidirectional transfer loop. */
1020 struct bidirectional_transfer_state {
1021 /* Direction from program to git. */
1022 struct unidirectional_transfer ptg;
1023 /* Direction from git to program. */
1024 struct unidirectional_transfer gtp;
1027 static void *udt_copy_task_routine(void *udt)
1029 struct unidirectional_transfer *t = (struct unidirectional_transfer *)udt;
1030 while (t->state != SSTATE_FINISHED) {
1031 if (STATE_NEEDS_READING(t->state))
1032 if (udt_do_read(t))
1033 return NULL;
1034 if (STATE_NEEDS_WRITING(t->state))
1035 if (udt_do_write(t))
1036 return NULL;
1037 if (STATE_NEEDS_CLOSING(t->state))
1038 udt_close_if_finished(t);
1040 return udt; /* Just some non-NULL value. */
1043 #ifndef NO_PTHREADS
1046 * Join thread, with apporiate errors on failure. Name is name for the
1047 * thread (for error messages). Returns 0 on success, 1 on failure.
1049 static int tloop_join(pthread_t thread, const char *name)
1051 int err;
1052 void *tret;
1053 err = pthread_join(thread, &tret);
1054 if (!tret) {
1055 error("%s thread failed", name);
1056 return 1;
1058 if (err) {
1059 error("%s thread failed to join: %s", name, strerror(err));
1060 return 1;
1062 return 0;
1066 * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1067 * -1 on failure.
1069 static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1071 pthread_t gtp_thread;
1072 pthread_t ptg_thread;
1073 int err;
1074 int ret = 0;
1075 err = pthread_create(&gtp_thread, NULL, udt_copy_task_routine,
1076 &s->gtp);
1077 if (err)
1078 die("Can't start thread for copying data: %s", strerror(err));
1079 err = pthread_create(&ptg_thread, NULL, udt_copy_task_routine,
1080 &s->ptg);
1081 if (err)
1082 die("Can't start thread for copying data: %s", strerror(err));
1084 ret |= tloop_join(gtp_thread, "Git to program copy");
1085 ret |= tloop_join(ptg_thread, "Program to git copy");
1086 return ret;
1088 #else
1090 /* Close the source and target (for writing) for transfer. */
1091 static void udt_kill_transfer(struct unidirectional_transfer *t)
1093 t->state = SSTATE_FINISHED;
1095 * Socket read end left open isn't a disaster if nobody
1096 * attempts to read from it (mingw compat headers do not
1097 * have SHUT_RD)...
1099 * We can't fully close the socket since otherwise gtp
1100 * task would first close the socket it sends data to
1101 * while closing the ptg file descriptors.
1103 if (!t->src_is_sock)
1104 close(t->src);
1105 if (t->dest_is_sock)
1106 shutdown(t->dest, SHUT_WR);
1107 else
1108 close(t->dest);
1112 * Join process, with apporiate errors on failure. Name is name for the
1113 * process (for error messages). Returns 0 on success, 1 on failure.
1115 static int tloop_join(pid_t pid, const char *name)
1117 int tret;
1118 if (waitpid(pid, &tret, 0) < 0) {
1119 error("%s process failed to wait: %s", name, strerror(errno));
1120 return 1;
1122 if (!WIFEXITED(tret) || WEXITSTATUS(tret)) {
1123 error("%s process failed", name);
1124 return 1;
1126 return 0;
1130 * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1131 * -1 on failure.
1133 static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1135 pid_t pid1, pid2;
1136 int ret = 0;
1138 /* Fork thread #1: git to program. */
1139 pid1 = fork();
1140 if (pid1 < 0)
1141 die_errno("Can't start thread for copying data");
1142 else if (pid1 == 0) {
1143 udt_kill_transfer(&s->ptg);
1144 exit(udt_copy_task_routine(&s->gtp) ? 0 : 1);
1147 /* Fork thread #2: program to git. */
1148 pid2 = fork();
1149 if (pid2 < 0)
1150 die_errno("Can't start thread for copying data");
1151 else if (pid2 == 0) {
1152 udt_kill_transfer(&s->gtp);
1153 exit(udt_copy_task_routine(&s->ptg) ? 0 : 1);
1157 * Close both streams in parent as to not interfere with
1158 * end of file detection and wait for both tasks to finish.
1160 udt_kill_transfer(&s->gtp);
1161 udt_kill_transfer(&s->ptg);
1162 ret |= tloop_join(pid1, "Git to program copy");
1163 ret |= tloop_join(pid2, "Program to git copy");
1164 return ret;
1166 #endif
1169 * Copies data from stdin to output and from input to stdout simultaneously.
1170 * Additionally filtering through given filter. If filter is NULL, uses
1171 * identity filter.
1173 int bidirectional_transfer_loop(int input, int output)
1175 struct bidirectional_transfer_state state;
1177 /* Fill the state fields. */
1178 state.ptg.src = input;
1179 state.ptg.dest = 1;
1180 state.ptg.src_is_sock = (input == output);
1181 state.ptg.dest_is_sock = 0;
1182 state.ptg.state = SSTATE_TRANSFERING;
1183 state.ptg.bufuse = 0;
1184 state.ptg.src_name = "remote input";
1185 state.ptg.dest_name = "stdout";
1187 state.gtp.src = 0;
1188 state.gtp.dest = output;
1189 state.gtp.src_is_sock = 0;
1190 state.gtp.dest_is_sock = (input == output);
1191 state.gtp.state = SSTATE_TRANSFERING;
1192 state.gtp.bufuse = 0;
1193 state.gtp.src_name = "stdin";
1194 state.gtp.dest_name = "remote output";
1196 return tloop_spawnwait_tasks(&state);