Start preparing for 1.8.4.2
[alt-git.git] / transport-helper.c
blob63cabc37e37dd338d3d9ee0764f099840d937600
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"
12 #include "sigchain.h"
13 #include "argv-array.h"
14 #include "refs.h"
16 static int debug;
18 struct helper_data {
19 const char *name;
20 struct child_process *helper;
21 FILE *out;
22 unsigned fetch : 1,
23 import : 1,
24 bidi_import : 1,
25 export : 1,
26 option : 1,
27 push : 1,
28 connect : 1,
29 signed_tags : 1,
30 no_disconnect_req : 1;
31 char *export_marks;
32 char *import_marks;
33 /* These go from remote name (as in "list") to private name */
34 struct refspec *refspecs;
35 int refspec_nr;
36 /* Transport options for fetch-pack/send-pack (should one of
37 * those be invoked).
39 struct git_transport_options transport_options;
42 static void sendline(struct helper_data *helper, struct strbuf *buffer)
44 if (debug)
45 fprintf(stderr, "Debug: Remote helper: -> %s", buffer->buf);
46 if (write_in_full(helper->helper->in, buffer->buf, buffer->len)
47 != buffer->len)
48 die_errno("Full write to remote helper failed");
51 static int recvline_fh(FILE *helper, struct strbuf *buffer, const char *name)
53 strbuf_reset(buffer);
54 if (debug)
55 fprintf(stderr, "Debug: Remote helper: Waiting...\n");
56 if (strbuf_getline(buffer, helper, '\n') == EOF) {
57 if (debug)
58 fprintf(stderr, "Debug: Remote helper quit.\n");
59 exit(128);
62 if (debug)
63 fprintf(stderr, "Debug: Remote helper: <- %s\n", buffer->buf);
64 return 0;
67 static int recvline(struct helper_data *helper, struct strbuf *buffer)
69 return recvline_fh(helper->out, buffer, helper->name);
72 static void xchgline(struct helper_data *helper, struct strbuf *buffer)
74 sendline(helper, buffer);
75 recvline(helper, buffer);
78 static void write_constant(int fd, const char *str)
80 if (debug)
81 fprintf(stderr, "Debug: Remote helper: -> %s", str);
82 if (write_in_full(fd, str, strlen(str)) != strlen(str))
83 die_errno("Full write to remote helper failed");
86 static const char *remove_ext_force(const char *url)
88 if (url) {
89 const char *colon = strchr(url, ':');
90 if (colon && colon[1] == ':')
91 return colon + 2;
93 return url;
96 static void do_take_over(struct transport *transport)
98 struct helper_data *data;
99 data = (struct helper_data *)transport->data;
100 transport_take_over(transport, data->helper);
101 fclose(data->out);
102 free(data);
105 static struct child_process *get_helper(struct transport *transport)
107 struct helper_data *data = transport->data;
108 struct argv_array argv = ARGV_ARRAY_INIT;
109 struct strbuf buf = STRBUF_INIT;
110 struct child_process *helper;
111 const char **refspecs = NULL;
112 int refspec_nr = 0;
113 int refspec_alloc = 0;
114 int duped;
115 int code;
116 char git_dir_buf[sizeof(GIT_DIR_ENVIRONMENT) + PATH_MAX + 1];
117 const char *helper_env[] = {
118 git_dir_buf,
119 NULL
123 if (data->helper)
124 return data->helper;
126 helper = xcalloc(1, sizeof(*helper));
127 helper->in = -1;
128 helper->out = -1;
129 helper->err = 0;
130 argv_array_pushf(&argv, "git-remote-%s", data->name);
131 argv_array_push(&argv, transport->remote->name);
132 argv_array_push(&argv, remove_ext_force(transport->url));
133 helper->argv = argv_array_detach(&argv, NULL);
134 helper->git_cmd = 0;
135 helper->silent_exec_failure = 1;
137 snprintf(git_dir_buf, sizeof(git_dir_buf), "%s=%s", GIT_DIR_ENVIRONMENT, get_git_dir());
138 helper->env = helper_env;
140 code = start_command(helper);
141 if (code < 0 && errno == ENOENT)
142 die("Unable to find remote helper for '%s'", data->name);
143 else if (code != 0)
144 exit(code);
146 data->helper = helper;
147 data->no_disconnect_req = 0;
150 * Open the output as FILE* so strbuf_getline() can be used.
151 * Do this with duped fd because fclose() will close the fd,
152 * and stuff like taking over will require the fd to remain.
154 duped = dup(helper->out);
155 if (duped < 0)
156 die_errno("Can't dup helper output fd");
157 data->out = xfdopen(duped, "r");
159 write_constant(helper->in, "capabilities\n");
161 while (1) {
162 const char *capname;
163 int mandatory = 0;
164 recvline(data, &buf);
166 if (!*buf.buf)
167 break;
169 if (*buf.buf == '*') {
170 capname = buf.buf + 1;
171 mandatory = 1;
172 } else
173 capname = buf.buf;
175 if (debug)
176 fprintf(stderr, "Debug: Got cap %s\n", capname);
177 if (!strcmp(capname, "fetch"))
178 data->fetch = 1;
179 else if (!strcmp(capname, "option"))
180 data->option = 1;
181 else if (!strcmp(capname, "push"))
182 data->push = 1;
183 else if (!strcmp(capname, "import"))
184 data->import = 1;
185 else if (!strcmp(capname, "bidi-import"))
186 data->bidi_import = 1;
187 else if (!strcmp(capname, "export"))
188 data->export = 1;
189 else if (!data->refspecs && !prefixcmp(capname, "refspec ")) {
190 ALLOC_GROW(refspecs,
191 refspec_nr + 1,
192 refspec_alloc);
193 refspecs[refspec_nr++] = xstrdup(capname + strlen("refspec "));
194 } else if (!strcmp(capname, "connect")) {
195 data->connect = 1;
196 } else if (!strcmp(capname, "signed-tags")) {
197 data->signed_tags = 1;
198 } else if (!prefixcmp(capname, "export-marks ")) {
199 struct strbuf arg = STRBUF_INIT;
200 strbuf_addstr(&arg, "--export-marks=");
201 strbuf_addstr(&arg, capname + strlen("export-marks "));
202 data->export_marks = strbuf_detach(&arg, NULL);
203 } else if (!prefixcmp(capname, "import-marks")) {
204 struct strbuf arg = STRBUF_INIT;
205 strbuf_addstr(&arg, "--import-marks=");
206 strbuf_addstr(&arg, capname + strlen("import-marks "));
207 data->import_marks = strbuf_detach(&arg, NULL);
208 } else if (mandatory) {
209 die("Unknown mandatory capability %s. This remote "
210 "helper probably needs newer version of Git.",
211 capname);
214 if (refspecs) {
215 int i;
216 data->refspec_nr = refspec_nr;
217 data->refspecs = parse_fetch_refspec(refspec_nr, refspecs);
218 for (i = 0; i < refspec_nr; i++)
219 free((char *)refspecs[i]);
220 free(refspecs);
221 } else if (data->import || data->bidi_import || data->export) {
222 warning("This remote helper should implement refspec capability.");
224 strbuf_release(&buf);
225 if (debug)
226 fprintf(stderr, "Debug: Capabilities complete.\n");
227 return data->helper;
230 static int disconnect_helper(struct transport *transport)
232 struct helper_data *data = transport->data;
233 int res = 0;
235 if (data->helper) {
236 if (debug)
237 fprintf(stderr, "Debug: Disconnecting.\n");
238 if (!data->no_disconnect_req) {
240 * Ignore write errors; there's nothing we can do,
241 * since we're about to close the pipe anyway. And the
242 * most likely error is EPIPE due to the helper dying
243 * to report an error itself.
245 sigchain_push(SIGPIPE, SIG_IGN);
246 xwrite(data->helper->in, "\n", 1);
247 sigchain_pop(SIGPIPE);
249 close(data->helper->in);
250 close(data->helper->out);
251 fclose(data->out);
252 res = finish_command(data->helper);
253 argv_array_free_detached(data->helper->argv);
254 free(data->helper);
255 data->helper = NULL;
257 return res;
260 static const char *unsupported_options[] = {
261 TRANS_OPT_UPLOADPACK,
262 TRANS_OPT_RECEIVEPACK,
263 TRANS_OPT_THIN,
264 TRANS_OPT_KEEP
266 static const char *boolean_options[] = {
267 TRANS_OPT_THIN,
268 TRANS_OPT_KEEP,
269 TRANS_OPT_FOLLOWTAGS
272 static int set_helper_option(struct transport *transport,
273 const char *name, const char *value)
275 struct helper_data *data = transport->data;
276 struct strbuf buf = STRBUF_INIT;
277 int i, ret, is_bool = 0;
279 get_helper(transport);
281 if (!data->option)
282 return 1;
284 for (i = 0; i < ARRAY_SIZE(unsupported_options); i++) {
285 if (!strcmp(name, unsupported_options[i]))
286 return 1;
289 for (i = 0; i < ARRAY_SIZE(boolean_options); i++) {
290 if (!strcmp(name, boolean_options[i])) {
291 is_bool = 1;
292 break;
296 strbuf_addf(&buf, "option %s ", name);
297 if (is_bool)
298 strbuf_addstr(&buf, value ? "true" : "false");
299 else
300 quote_c_style(value, &buf, NULL, 0);
301 strbuf_addch(&buf, '\n');
303 xchgline(data, &buf);
305 if (!strcmp(buf.buf, "ok"))
306 ret = 0;
307 else if (!prefixcmp(buf.buf, "error")) {
308 ret = -1;
309 } else if (!strcmp(buf.buf, "unsupported"))
310 ret = 1;
311 else {
312 warning("%s unexpectedly said: '%s'", data->name, buf.buf);
313 ret = 1;
315 strbuf_release(&buf);
316 return ret;
319 static void standard_options(struct transport *t)
321 char buf[16];
322 int n;
323 int v = t->verbose;
325 set_helper_option(t, "progress", t->progress ? "true" : "false");
327 n = snprintf(buf, sizeof(buf), "%d", v + 1);
328 if (n >= sizeof(buf))
329 die("impossibly large verbosity value");
330 set_helper_option(t, "verbosity", buf);
333 static int release_helper(struct transport *transport)
335 int res = 0;
336 struct helper_data *data = transport->data;
337 free_refspec(data->refspec_nr, data->refspecs);
338 data->refspecs = NULL;
339 res = disconnect_helper(transport);
340 free(transport->data);
341 return res;
344 static int fetch_with_fetch(struct transport *transport,
345 int nr_heads, struct ref **to_fetch)
347 struct helper_data *data = transport->data;
348 int i;
349 struct strbuf buf = STRBUF_INIT;
351 standard_options(transport);
353 for (i = 0; i < nr_heads; i++) {
354 const struct ref *posn = to_fetch[i];
355 if (posn->status & REF_STATUS_UPTODATE)
356 continue;
358 strbuf_addf(&buf, "fetch %s %s\n",
359 sha1_to_hex(posn->old_sha1), posn->name);
362 strbuf_addch(&buf, '\n');
363 sendline(data, &buf);
365 while (1) {
366 recvline(data, &buf);
368 if (!prefixcmp(buf.buf, "lock ")) {
369 const char *name = buf.buf + 5;
370 if (transport->pack_lockfile)
371 warning("%s also locked %s", data->name, name);
372 else
373 transport->pack_lockfile = xstrdup(name);
375 else if (!buf.len)
376 break;
377 else
378 warning("%s unexpectedly said: '%s'", data->name, buf.buf);
380 strbuf_release(&buf);
381 return 0;
384 static int get_importer(struct transport *transport, struct child_process *fastimport)
386 struct child_process *helper = get_helper(transport);
387 struct helper_data *data = transport->data;
388 struct argv_array argv = ARGV_ARRAY_INIT;
389 int cat_blob_fd, code;
390 memset(fastimport, 0, sizeof(*fastimport));
391 fastimport->in = helper->out;
392 argv_array_push(&argv, "fast-import");
393 argv_array_push(&argv, debug ? "--stats" : "--quiet");
395 if (data->bidi_import) {
396 cat_blob_fd = xdup(helper->in);
397 argv_array_pushf(&argv, "--cat-blob-fd=%d", cat_blob_fd);
399 fastimport->argv = argv.argv;
400 fastimport->git_cmd = 1;
402 code = start_command(fastimport);
403 return code;
406 static int get_exporter(struct transport *transport,
407 struct child_process *fastexport,
408 struct string_list *revlist_args)
410 struct helper_data *data = transport->data;
411 struct child_process *helper = get_helper(transport);
412 int argc = 0, i;
413 memset(fastexport, 0, sizeof(*fastexport));
415 /* we need to duplicate helper->in because we want to use it after
416 * fastexport is done with it. */
417 fastexport->out = dup(helper->in);
418 fastexport->argv = xcalloc(6 + revlist_args->nr, sizeof(*fastexport->argv));
419 fastexport->argv[argc++] = "fast-export";
420 fastexport->argv[argc++] = "--use-done-feature";
421 fastexport->argv[argc++] = data->signed_tags ?
422 "--signed-tags=verbatim" : "--signed-tags=warn-strip";
423 if (data->export_marks)
424 fastexport->argv[argc++] = data->export_marks;
425 if (data->import_marks)
426 fastexport->argv[argc++] = data->import_marks;
428 for (i = 0; i < revlist_args->nr; i++)
429 fastexport->argv[argc++] = revlist_args->items[i].string;
431 fastexport->git_cmd = 1;
432 return start_command(fastexport);
435 static int fetch_with_import(struct transport *transport,
436 int nr_heads, struct ref **to_fetch)
438 struct child_process fastimport;
439 struct helper_data *data = transport->data;
440 int i;
441 struct ref *posn;
442 struct strbuf buf = STRBUF_INIT;
444 get_helper(transport);
446 if (get_importer(transport, &fastimport))
447 die("Couldn't run fast-import");
449 for (i = 0; i < nr_heads; i++) {
450 posn = to_fetch[i];
451 if (posn->status & REF_STATUS_UPTODATE)
452 continue;
454 strbuf_addf(&buf, "import %s\n", posn->name);
455 sendline(data, &buf);
456 strbuf_reset(&buf);
459 write_constant(data->helper->in, "\n");
461 * remote-helpers that advertise the bidi-import capability are required to
462 * buffer the complete batch of import commands until this newline before
463 * sending data to fast-import.
464 * These helpers read back data from fast-import on their stdin, which could
465 * be mixed with import commands, otherwise.
468 if (finish_command(&fastimport))
469 die("Error while running fast-import");
470 argv_array_free_detached(fastimport.argv);
473 * The fast-import stream of a remote helper that advertises
474 * the "refspec" capability writes to the refs named after the
475 * right hand side of the first refspec matching each ref we
476 * were fetching.
478 * (If no "refspec" capability was specified, for historical
479 * reasons we default to the equivalent of *:*.)
481 * Store the result in to_fetch[i].old_sha1. Callers such
482 * as "git fetch" can use the value to write feedback to the
483 * terminal, populate FETCH_HEAD, and determine what new value
484 * should be written to peer_ref if the update is a
485 * fast-forward or this is a forced update.
487 for (i = 0; i < nr_heads; i++) {
488 char *private;
489 posn = to_fetch[i];
490 if (posn->status & REF_STATUS_UPTODATE)
491 continue;
492 if (data->refspecs)
493 private = apply_refspecs(data->refspecs, data->refspec_nr, posn->name);
494 else
495 private = xstrdup(posn->name);
496 if (private) {
497 read_ref(private, posn->old_sha1);
498 free(private);
501 strbuf_release(&buf);
502 return 0;
505 static int process_connect_service(struct transport *transport,
506 const char *name, const char *exec)
508 struct helper_data *data = transport->data;
509 struct strbuf cmdbuf = STRBUF_INIT;
510 struct child_process *helper;
511 int r, duped, ret = 0;
512 FILE *input;
514 helper = get_helper(transport);
517 * Yes, dup the pipe another time, as we need unbuffered version
518 * of input pipe as FILE*. fclose() closes the underlying fd and
519 * stream buffering only can be changed before first I/O operation
520 * on it.
522 duped = dup(helper->out);
523 if (duped < 0)
524 die_errno("Can't dup helper output fd");
525 input = xfdopen(duped, "r");
526 setvbuf(input, NULL, _IONBF, 0);
529 * Handle --upload-pack and friends. This is fire and forget...
530 * just warn if it fails.
532 if (strcmp(name, exec)) {
533 r = set_helper_option(transport, "servpath", exec);
534 if (r > 0)
535 warning("Setting remote service path not supported by protocol.");
536 else if (r < 0)
537 warning("Invalid remote service path.");
540 if (data->connect)
541 strbuf_addf(&cmdbuf, "connect %s\n", name);
542 else
543 goto exit;
545 sendline(data, &cmdbuf);
546 recvline_fh(input, &cmdbuf, name);
547 if (!strcmp(cmdbuf.buf, "")) {
548 data->no_disconnect_req = 1;
549 if (debug)
550 fprintf(stderr, "Debug: Smart transport connection "
551 "ready.\n");
552 ret = 1;
553 } else if (!strcmp(cmdbuf.buf, "fallback")) {
554 if (debug)
555 fprintf(stderr, "Debug: Falling back to dumb "
556 "transport.\n");
557 } else
558 die("Unknown response to connect: %s",
559 cmdbuf.buf);
561 exit:
562 fclose(input);
563 return ret;
566 static int process_connect(struct transport *transport,
567 int for_push)
569 struct helper_data *data = transport->data;
570 const char *name;
571 const char *exec;
573 name = for_push ? "git-receive-pack" : "git-upload-pack";
574 if (for_push)
575 exec = data->transport_options.receivepack;
576 else
577 exec = data->transport_options.uploadpack;
579 return process_connect_service(transport, name, exec);
582 static int connect_helper(struct transport *transport, const char *name,
583 const char *exec, int fd[2])
585 struct helper_data *data = transport->data;
587 /* Get_helper so connect is inited. */
588 get_helper(transport);
589 if (!data->connect)
590 die("Operation not supported by protocol.");
592 if (!process_connect_service(transport, name, exec))
593 die("Can't connect to subservice %s.", name);
595 fd[0] = data->helper->out;
596 fd[1] = data->helper->in;
597 return 0;
600 static int fetch(struct transport *transport,
601 int nr_heads, struct ref **to_fetch)
603 struct helper_data *data = transport->data;
604 int i, count;
606 if (process_connect(transport, 0)) {
607 do_take_over(transport);
608 return transport->fetch(transport, nr_heads, to_fetch);
611 count = 0;
612 for (i = 0; i < nr_heads; i++)
613 if (!(to_fetch[i]->status & REF_STATUS_UPTODATE))
614 count++;
616 if (!count)
617 return 0;
619 if (data->fetch)
620 return fetch_with_fetch(transport, nr_heads, to_fetch);
622 if (data->import)
623 return fetch_with_import(transport, nr_heads, to_fetch);
625 return -1;
628 static int push_update_ref_status(struct strbuf *buf,
629 struct ref **ref,
630 struct ref *remote_refs)
632 char *refname, *msg;
633 int status;
635 if (!prefixcmp(buf->buf, "ok ")) {
636 status = REF_STATUS_OK;
637 refname = buf->buf + 3;
638 } else if (!prefixcmp(buf->buf, "error ")) {
639 status = REF_STATUS_REMOTE_REJECT;
640 refname = buf->buf + 6;
641 } else
642 die("expected ok/error, helper said '%s'", buf->buf);
644 msg = strchr(refname, ' ');
645 if (msg) {
646 struct strbuf msg_buf = STRBUF_INIT;
647 const char *end;
649 *msg++ = '\0';
650 if (!unquote_c_style(&msg_buf, msg, &end))
651 msg = strbuf_detach(&msg_buf, NULL);
652 else
653 msg = xstrdup(msg);
654 strbuf_release(&msg_buf);
656 if (!strcmp(msg, "no match")) {
657 status = REF_STATUS_NONE;
658 free(msg);
659 msg = NULL;
661 else if (!strcmp(msg, "up to date")) {
662 status = REF_STATUS_UPTODATE;
663 free(msg);
664 msg = NULL;
666 else if (!strcmp(msg, "non-fast forward")) {
667 status = REF_STATUS_REJECT_NONFASTFORWARD;
668 free(msg);
669 msg = NULL;
671 else if (!strcmp(msg, "already exists")) {
672 status = REF_STATUS_REJECT_ALREADY_EXISTS;
673 free(msg);
674 msg = NULL;
676 else if (!strcmp(msg, "fetch first")) {
677 status = REF_STATUS_REJECT_FETCH_FIRST;
678 free(msg);
679 msg = NULL;
681 else if (!strcmp(msg, "needs force")) {
682 status = REF_STATUS_REJECT_NEEDS_FORCE;
683 free(msg);
684 msg = NULL;
688 if (*ref)
689 *ref = find_ref_by_name(*ref, refname);
690 if (!*ref)
691 *ref = find_ref_by_name(remote_refs, refname);
692 if (!*ref) {
693 warning("helper reported unexpected status of %s", refname);
694 return 1;
697 if ((*ref)->status != REF_STATUS_NONE) {
699 * Earlier, the ref was marked not to be pushed, so ignore the ref
700 * status reported by the remote helper if the latter is 'no match'.
702 if (status == REF_STATUS_NONE)
703 return 1;
706 (*ref)->status = status;
707 (*ref)->remote_status = msg;
708 return !(status == REF_STATUS_OK);
711 static void push_update_refs_status(struct helper_data *data,
712 struct ref *remote_refs)
714 struct strbuf buf = STRBUF_INIT;
715 struct ref *ref = remote_refs;
716 for (;;) {
717 char *private;
719 recvline(data, &buf);
720 if (!buf.len)
721 break;
723 if (push_update_ref_status(&buf, &ref, remote_refs))
724 continue;
726 if (!data->refspecs)
727 continue;
729 /* propagate back the update to the remote namespace */
730 private = apply_refspecs(data->refspecs, data->refspec_nr, ref->name);
731 if (!private)
732 continue;
733 update_ref("update by helper", private, ref->new_sha1, NULL, 0, 0);
734 free(private);
736 strbuf_release(&buf);
739 static int push_refs_with_push(struct transport *transport,
740 struct ref *remote_refs, int flags)
742 int force_all = flags & TRANSPORT_PUSH_FORCE;
743 int mirror = flags & TRANSPORT_PUSH_MIRROR;
744 struct helper_data *data = transport->data;
745 struct strbuf buf = STRBUF_INIT;
746 struct ref *ref;
748 get_helper(transport);
749 if (!data->push)
750 return 1;
752 for (ref = remote_refs; ref; ref = ref->next) {
753 if (!ref->peer_ref && !mirror)
754 continue;
756 /* Check for statuses set by set_ref_status_for_push() */
757 switch (ref->status) {
758 case REF_STATUS_REJECT_NONFASTFORWARD:
759 case REF_STATUS_REJECT_ALREADY_EXISTS:
760 case REF_STATUS_UPTODATE:
761 continue;
762 default:
763 ; /* do nothing */
766 if (force_all)
767 ref->force = 1;
769 strbuf_addstr(&buf, "push ");
770 if (!ref->deletion) {
771 if (ref->force)
772 strbuf_addch(&buf, '+');
773 if (ref->peer_ref)
774 strbuf_addstr(&buf, ref->peer_ref->name);
775 else
776 strbuf_addstr(&buf, sha1_to_hex(ref->new_sha1));
778 strbuf_addch(&buf, ':');
779 strbuf_addstr(&buf, ref->name);
780 strbuf_addch(&buf, '\n');
782 if (buf.len == 0)
783 return 0;
785 standard_options(transport);
787 if (flags & TRANSPORT_PUSH_DRY_RUN) {
788 if (set_helper_option(transport, "dry-run", "true") != 0)
789 die("helper %s does not support dry-run", data->name);
792 strbuf_addch(&buf, '\n');
793 sendline(data, &buf);
794 strbuf_release(&buf);
796 push_update_refs_status(data, remote_refs);
797 return 0;
800 static int push_refs_with_export(struct transport *transport,
801 struct ref *remote_refs, int flags)
803 struct ref *ref;
804 struct child_process *helper, exporter;
805 struct helper_data *data = transport->data;
806 struct string_list revlist_args = STRING_LIST_INIT_NODUP;
807 struct strbuf buf = STRBUF_INIT;
809 if (!data->refspecs)
810 die("remote-helper doesn't support push; refspec needed");
812 if (flags & TRANSPORT_PUSH_DRY_RUN) {
813 if (set_helper_option(transport, "dry-run", "true") != 0)
814 die("helper %s does not support dry-run", data->name);
817 helper = get_helper(transport);
819 write_constant(helper->in, "export\n");
821 strbuf_reset(&buf);
823 for (ref = remote_refs; ref; ref = ref->next) {
824 char *private;
825 unsigned char sha1[20];
827 if (ref->deletion)
828 die("remote-helpers do not support ref deletion");
830 private = apply_refspecs(data->refspecs, data->refspec_nr, ref->name);
831 if (private && !get_sha1(private, sha1)) {
832 strbuf_addf(&buf, "^%s", private);
833 string_list_append(&revlist_args, strbuf_detach(&buf, NULL));
834 hashcpy(ref->old_sha1, sha1);
836 free(private);
838 if (ref->deletion)
839 die("remote-helpers do not support ref deletion");
841 if (ref->peer_ref) {
842 if (strcmp(ref->peer_ref->name, ref->name))
843 die("remote-helpers do not support old:new syntax");
844 string_list_append(&revlist_args, ref->peer_ref->name);
848 if (get_exporter(transport, &exporter, &revlist_args))
849 die("Couldn't run fast-export");
851 if (finish_command(&exporter))
852 die("Error while running fast-export");
853 push_update_refs_status(data, remote_refs);
854 return 0;
857 static int push_refs(struct transport *transport,
858 struct ref *remote_refs, int flags)
860 struct helper_data *data = transport->data;
862 if (process_connect(transport, 1)) {
863 do_take_over(transport);
864 return transport->push_refs(transport, remote_refs, flags);
867 if (!remote_refs) {
868 fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
869 "Perhaps you should specify a branch such as 'master'.\n");
870 return 0;
873 if (data->push)
874 return push_refs_with_push(transport, remote_refs, flags);
876 if (data->export)
877 return push_refs_with_export(transport, remote_refs, flags);
879 return -1;
883 static int has_attribute(const char *attrs, const char *attr) {
884 int len;
885 if (!attrs)
886 return 0;
888 len = strlen(attr);
889 for (;;) {
890 const char *space = strchrnul(attrs, ' ');
891 if (len == space - attrs && !strncmp(attrs, attr, len))
892 return 1;
893 if (!*space)
894 return 0;
895 attrs = space + 1;
899 static struct ref *get_refs_list(struct transport *transport, int for_push)
901 struct helper_data *data = transport->data;
902 struct child_process *helper;
903 struct ref *ret = NULL;
904 struct ref **tail = &ret;
905 struct ref *posn;
906 struct strbuf buf = STRBUF_INIT;
908 helper = get_helper(transport);
910 if (process_connect(transport, for_push)) {
911 do_take_over(transport);
912 return transport->get_refs_list(transport, for_push);
915 if (data->push && for_push)
916 write_str_in_full(helper->in, "list for-push\n");
917 else
918 write_str_in_full(helper->in, "list\n");
920 while (1) {
921 char *eov, *eon;
922 recvline(data, &buf);
924 if (!*buf.buf)
925 break;
927 eov = strchr(buf.buf, ' ');
928 if (!eov)
929 die("Malformed response in ref list: %s", buf.buf);
930 eon = strchr(eov + 1, ' ');
931 *eov = '\0';
932 if (eon)
933 *eon = '\0';
934 *tail = alloc_ref(eov + 1);
935 if (buf.buf[0] == '@')
936 (*tail)->symref = xstrdup(buf.buf + 1);
937 else if (buf.buf[0] != '?')
938 get_sha1_hex(buf.buf, (*tail)->old_sha1);
939 if (eon) {
940 if (has_attribute(eon + 1, "unchanged")) {
941 (*tail)->status |= REF_STATUS_UPTODATE;
942 read_ref((*tail)->name, (*tail)->old_sha1);
945 tail = &((*tail)->next);
947 if (debug)
948 fprintf(stderr, "Debug: Read ref listing.\n");
949 strbuf_release(&buf);
951 for (posn = ret; posn; posn = posn->next)
952 resolve_remote_symref(posn, ret);
954 return ret;
957 int transport_helper_init(struct transport *transport, const char *name)
959 struct helper_data *data = xcalloc(sizeof(*data), 1);
960 data->name = name;
962 if (getenv("GIT_TRANSPORT_HELPER_DEBUG"))
963 debug = 1;
965 transport->data = data;
966 transport->set_option = set_helper_option;
967 transport->get_refs_list = get_refs_list;
968 transport->fetch = fetch;
969 transport->push_refs = push_refs;
970 transport->disconnect = release_helper;
971 transport->connect = connect_helper;
972 transport->smart_options = &(data->transport_options);
973 return 0;
977 * Linux pipes can buffer 65536 bytes at once (and most platforms can
978 * buffer less), so attempt reads and writes with up to that size.
980 #define BUFFERSIZE 65536
981 /* This should be enough to hold debugging message. */
982 #define PBUFFERSIZE 8192
984 /* Print bidirectional transfer loop debug message. */
985 __attribute__((format (printf, 1, 2)))
986 static void transfer_debug(const char *fmt, ...)
988 va_list args;
989 char msgbuf[PBUFFERSIZE];
990 static int debug_enabled = -1;
992 if (debug_enabled < 0)
993 debug_enabled = getenv("GIT_TRANSLOOP_DEBUG") ? 1 : 0;
994 if (!debug_enabled)
995 return;
997 va_start(args, fmt);
998 vsnprintf(msgbuf, PBUFFERSIZE, fmt, args);
999 va_end(args);
1000 fprintf(stderr, "Transfer loop debugging: %s\n", msgbuf);
1003 /* Stream state: More data may be coming in this direction. */
1004 #define SSTATE_TRANSFERING 0
1006 * Stream state: No more data coming in this direction, flushing rest of
1007 * data.
1009 #define SSTATE_FLUSHING 1
1010 /* Stream state: Transfer in this direction finished. */
1011 #define SSTATE_FINISHED 2
1013 #define STATE_NEEDS_READING(state) ((state) <= SSTATE_TRANSFERING)
1014 #define STATE_NEEDS_WRITING(state) ((state) <= SSTATE_FLUSHING)
1015 #define STATE_NEEDS_CLOSING(state) ((state) == SSTATE_FLUSHING)
1017 /* Unidirectional transfer. */
1018 struct unidirectional_transfer {
1019 /* Source */
1020 int src;
1021 /* Destination */
1022 int dest;
1023 /* Is source socket? */
1024 int src_is_sock;
1025 /* Is destination socket? */
1026 int dest_is_sock;
1027 /* Transfer state (TRANSFERRING/FLUSHING/FINISHED) */
1028 int state;
1029 /* Buffer. */
1030 char buf[BUFFERSIZE];
1031 /* Buffer used. */
1032 size_t bufuse;
1033 /* Name of source. */
1034 const char *src_name;
1035 /* Name of destination. */
1036 const char *dest_name;
1039 /* Closes the target (for writing) if transfer has finished. */
1040 static void udt_close_if_finished(struct unidirectional_transfer *t)
1042 if (STATE_NEEDS_CLOSING(t->state) && !t->bufuse) {
1043 t->state = SSTATE_FINISHED;
1044 if (t->dest_is_sock)
1045 shutdown(t->dest, SHUT_WR);
1046 else
1047 close(t->dest);
1048 transfer_debug("Closed %s.", t->dest_name);
1053 * Tries to read read data from source into buffer. If buffer is full,
1054 * no data is read. Returns 0 on success, -1 on error.
1056 static int udt_do_read(struct unidirectional_transfer *t)
1058 ssize_t bytes;
1060 if (t->bufuse == BUFFERSIZE)
1061 return 0; /* No space for more. */
1063 transfer_debug("%s is readable", t->src_name);
1064 bytes = read(t->src, t->buf + t->bufuse, BUFFERSIZE - t->bufuse);
1065 if (bytes < 0 && errno != EWOULDBLOCK && errno != EAGAIN &&
1066 errno != EINTR) {
1067 error("read(%s) failed: %s", t->src_name, strerror(errno));
1068 return -1;
1069 } else if (bytes == 0) {
1070 transfer_debug("%s EOF (with %i bytes in buffer)",
1071 t->src_name, (int)t->bufuse);
1072 t->state = SSTATE_FLUSHING;
1073 } else if (bytes > 0) {
1074 t->bufuse += bytes;
1075 transfer_debug("Read %i bytes from %s (buffer now at %i)",
1076 (int)bytes, t->src_name, (int)t->bufuse);
1078 return 0;
1081 /* Tries to write data from buffer into destination. If buffer is empty,
1082 * no data is written. Returns 0 on success, -1 on error.
1084 static int udt_do_write(struct unidirectional_transfer *t)
1086 ssize_t bytes;
1088 if (t->bufuse == 0)
1089 return 0; /* Nothing to write. */
1091 transfer_debug("%s is writable", t->dest_name);
1092 bytes = write(t->dest, t->buf, t->bufuse);
1093 if (bytes < 0 && errno != EWOULDBLOCK && errno != EAGAIN &&
1094 errno != EINTR) {
1095 error("write(%s) failed: %s", t->dest_name, strerror(errno));
1096 return -1;
1097 } else if (bytes > 0) {
1098 t->bufuse -= bytes;
1099 if (t->bufuse)
1100 memmove(t->buf, t->buf + bytes, t->bufuse);
1101 transfer_debug("Wrote %i bytes to %s (buffer now at %i)",
1102 (int)bytes, t->dest_name, (int)t->bufuse);
1104 return 0;
1108 /* State of bidirectional transfer loop. */
1109 struct bidirectional_transfer_state {
1110 /* Direction from program to git. */
1111 struct unidirectional_transfer ptg;
1112 /* Direction from git to program. */
1113 struct unidirectional_transfer gtp;
1116 static void *udt_copy_task_routine(void *udt)
1118 struct unidirectional_transfer *t = (struct unidirectional_transfer *)udt;
1119 while (t->state != SSTATE_FINISHED) {
1120 if (STATE_NEEDS_READING(t->state))
1121 if (udt_do_read(t))
1122 return NULL;
1123 if (STATE_NEEDS_WRITING(t->state))
1124 if (udt_do_write(t))
1125 return NULL;
1126 if (STATE_NEEDS_CLOSING(t->state))
1127 udt_close_if_finished(t);
1129 return udt; /* Just some non-NULL value. */
1132 #ifndef NO_PTHREADS
1135 * Join thread, with appropriate errors on failure. Name is name for the
1136 * thread (for error messages). Returns 0 on success, 1 on failure.
1138 static int tloop_join(pthread_t thread, const char *name)
1140 int err;
1141 void *tret;
1142 err = pthread_join(thread, &tret);
1143 if (!tret) {
1144 error("%s thread failed", name);
1145 return 1;
1147 if (err) {
1148 error("%s thread failed to join: %s", name, strerror(err));
1149 return 1;
1151 return 0;
1155 * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1156 * -1 on failure.
1158 static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1160 pthread_t gtp_thread;
1161 pthread_t ptg_thread;
1162 int err;
1163 int ret = 0;
1164 err = pthread_create(&gtp_thread, NULL, udt_copy_task_routine,
1165 &s->gtp);
1166 if (err)
1167 die("Can't start thread for copying data: %s", strerror(err));
1168 err = pthread_create(&ptg_thread, NULL, udt_copy_task_routine,
1169 &s->ptg);
1170 if (err)
1171 die("Can't start thread for copying data: %s", strerror(err));
1173 ret |= tloop_join(gtp_thread, "Git to program copy");
1174 ret |= tloop_join(ptg_thread, "Program to git copy");
1175 return ret;
1177 #else
1179 /* Close the source and target (for writing) for transfer. */
1180 static void udt_kill_transfer(struct unidirectional_transfer *t)
1182 t->state = SSTATE_FINISHED;
1184 * Socket read end left open isn't a disaster if nobody
1185 * attempts to read from it (mingw compat headers do not
1186 * have SHUT_RD)...
1188 * We can't fully close the socket since otherwise gtp
1189 * task would first close the socket it sends data to
1190 * while closing the ptg file descriptors.
1192 if (!t->src_is_sock)
1193 close(t->src);
1194 if (t->dest_is_sock)
1195 shutdown(t->dest, SHUT_WR);
1196 else
1197 close(t->dest);
1201 * Join process, with appropriate errors on failure. Name is name for the
1202 * process (for error messages). Returns 0 on success, 1 on failure.
1204 static int tloop_join(pid_t pid, const char *name)
1206 int tret;
1207 if (waitpid(pid, &tret, 0) < 0) {
1208 error("%s process failed to wait: %s", name, strerror(errno));
1209 return 1;
1211 if (!WIFEXITED(tret) || WEXITSTATUS(tret)) {
1212 error("%s process failed", name);
1213 return 1;
1215 return 0;
1219 * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1220 * -1 on failure.
1222 static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1224 pid_t pid1, pid2;
1225 int ret = 0;
1227 /* Fork thread #1: git to program. */
1228 pid1 = fork();
1229 if (pid1 < 0)
1230 die_errno("Can't start thread for copying data");
1231 else if (pid1 == 0) {
1232 udt_kill_transfer(&s->ptg);
1233 exit(udt_copy_task_routine(&s->gtp) ? 0 : 1);
1236 /* Fork thread #2: program to git. */
1237 pid2 = fork();
1238 if (pid2 < 0)
1239 die_errno("Can't start thread for copying data");
1240 else if (pid2 == 0) {
1241 udt_kill_transfer(&s->gtp);
1242 exit(udt_copy_task_routine(&s->ptg) ? 0 : 1);
1246 * Close both streams in parent as to not interfere with
1247 * end of file detection and wait for both tasks to finish.
1249 udt_kill_transfer(&s->gtp);
1250 udt_kill_transfer(&s->ptg);
1251 ret |= tloop_join(pid1, "Git to program copy");
1252 ret |= tloop_join(pid2, "Program to git copy");
1253 return ret;
1255 #endif
1258 * Copies data from stdin to output and from input to stdout simultaneously.
1259 * Additionally filtering through given filter. If filter is NULL, uses
1260 * identity filter.
1262 int bidirectional_transfer_loop(int input, int output)
1264 struct bidirectional_transfer_state state;
1266 /* Fill the state fields. */
1267 state.ptg.src = input;
1268 state.ptg.dest = 1;
1269 state.ptg.src_is_sock = (input == output);
1270 state.ptg.dest_is_sock = 0;
1271 state.ptg.state = SSTATE_TRANSFERING;
1272 state.ptg.bufuse = 0;
1273 state.ptg.src_name = "remote input";
1274 state.ptg.dest_name = "stdout";
1276 state.gtp.src = 0;
1277 state.gtp.dest = output;
1278 state.gtp.src_is_sock = 0;
1279 state.gtp.dest_is_sock = (input == output);
1280 state.gtp.state = SSTATE_TRANSFERING;
1281 state.gtp.bufuse = 0;
1282 state.gtp.src_name = "stdin";
1283 state.gtp.dest_name = "remote output";
1285 return tloop_spawnwait_tasks(&state);