Merge branch 'mh/write-refs-sooner-2.4' into maint
[git.git] / transport-helper.c
blob5d99a6bc2e7a10d40f6d8213e2f3cad254dbdb04
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"
15 static int debug;
17 struct helper_data {
18 const char *name;
19 struct child_process *helper;
20 FILE *out;
21 unsigned fetch : 1,
22 import : 1,
23 bidi_import : 1,
24 export : 1,
25 option : 1,
26 push : 1,
27 connect : 1,
28 signed_tags : 1,
29 check_connectivity : 1,
30 no_disconnect_req : 1,
31 no_private_update : 1;
32 char *export_marks;
33 char *import_marks;
34 /* These go from remote name (as in "list") to private name */
35 struct refspec *refspecs;
36 int refspec_nr;
37 /* Transport options for fetch-pack/send-pack (should one of
38 * those be invoked).
40 struct git_transport_options transport_options;
43 static void sendline(struct helper_data *helper, struct strbuf *buffer)
45 if (debug)
46 fprintf(stderr, "Debug: Remote helper: -> %s", buffer->buf);
47 if (write_in_full(helper->helper->in, buffer->buf, buffer->len)
48 != buffer->len)
49 die_errno("Full write to remote helper failed");
52 static int recvline_fh(FILE *helper, struct strbuf *buffer, const char *name)
54 strbuf_reset(buffer);
55 if (debug)
56 fprintf(stderr, "Debug: Remote helper: Waiting...\n");
57 if (strbuf_getline(buffer, helper, '\n') == EOF) {
58 if (debug)
59 fprintf(stderr, "Debug: Remote helper quit.\n");
60 return 1;
63 if (debug)
64 fprintf(stderr, "Debug: Remote helper: <- %s\n", buffer->buf);
65 return 0;
68 static int recvline(struct helper_data *helper, struct strbuf *buffer)
70 return recvline_fh(helper->out, buffer, helper->name);
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 void standard_options(struct transport *t);
102 static struct child_process *get_helper(struct transport *transport)
104 struct helper_data *data = transport->data;
105 struct strbuf buf = STRBUF_INIT;
106 struct child_process *helper;
107 const char **refspecs = NULL;
108 int refspec_nr = 0;
109 int refspec_alloc = 0;
110 int duped;
111 int code;
113 if (data->helper)
114 return data->helper;
116 helper = xmalloc(sizeof(*helper));
117 child_process_init(helper);
118 helper->in = -1;
119 helper->out = -1;
120 helper->err = 0;
121 argv_array_pushf(&helper->args, "git-remote-%s", data->name);
122 argv_array_push(&helper->args, transport->remote->name);
123 argv_array_push(&helper->args, remove_ext_force(transport->url));
124 helper->git_cmd = 0;
125 helper->silent_exec_failure = 1;
127 argv_array_pushf(&helper->env_array, "%s=%s", GIT_DIR_ENVIRONMENT,
128 get_git_dir());
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);
136 data->helper = helper;
137 data->no_disconnect_req = 0;
140 * Open the output as FILE* so strbuf_getline() can be used.
141 * Do this with duped fd because fclose() will close the fd,
142 * and stuff like taking over will require the fd to remain.
144 duped = dup(helper->out);
145 if (duped < 0)
146 die_errno("Can't dup helper output fd");
147 data->out = xfdopen(duped, "r");
149 write_constant(helper->in, "capabilities\n");
151 while (1) {
152 const char *capname, *arg;
153 int mandatory = 0;
154 if (recvline(data, &buf))
155 exit(128);
157 if (!*buf.buf)
158 break;
160 if (*buf.buf == '*') {
161 capname = buf.buf + 1;
162 mandatory = 1;
163 } else
164 capname = buf.buf;
166 if (debug)
167 fprintf(stderr, "Debug: Got cap %s\n", capname);
168 if (!strcmp(capname, "fetch"))
169 data->fetch = 1;
170 else if (!strcmp(capname, "option"))
171 data->option = 1;
172 else if (!strcmp(capname, "push"))
173 data->push = 1;
174 else if (!strcmp(capname, "import"))
175 data->import = 1;
176 else if (!strcmp(capname, "bidi-import"))
177 data->bidi_import = 1;
178 else if (!strcmp(capname, "export"))
179 data->export = 1;
180 else if (!strcmp(capname, "check-connectivity"))
181 data->check_connectivity = 1;
182 else if (!data->refspecs && skip_prefix(capname, "refspec ", &arg)) {
183 ALLOC_GROW(refspecs,
184 refspec_nr + 1,
185 refspec_alloc);
186 refspecs[refspec_nr++] = xstrdup(arg);
187 } else if (!strcmp(capname, "connect")) {
188 data->connect = 1;
189 } else if (!strcmp(capname, "signed-tags")) {
190 data->signed_tags = 1;
191 } else if (skip_prefix(capname, "export-marks ", &arg)) {
192 data->export_marks = xstrdup(arg);
193 } else if (skip_prefix(capname, "import-marks ", &arg)) {
194 data->import_marks = xstrdup(arg);
195 } else if (starts_with(capname, "no-private-update")) {
196 data->no_private_update = 1;
197 } else if (mandatory) {
198 die("Unknown mandatory capability %s. This remote "
199 "helper probably needs newer version of Git.",
200 capname);
203 if (refspecs) {
204 int i;
205 data->refspec_nr = refspec_nr;
206 data->refspecs = parse_fetch_refspec(refspec_nr, refspecs);
207 for (i = 0; i < refspec_nr; i++)
208 free((char *)refspecs[i]);
209 free(refspecs);
210 } else if (data->import || data->bidi_import || data->export) {
211 warning("This remote helper should implement refspec capability.");
213 strbuf_release(&buf);
214 if (debug)
215 fprintf(stderr, "Debug: Capabilities complete.\n");
216 standard_options(transport);
217 return data->helper;
220 static int disconnect_helper(struct transport *transport)
222 struct helper_data *data = transport->data;
223 int res = 0;
225 if (data->helper) {
226 if (debug)
227 fprintf(stderr, "Debug: Disconnecting.\n");
228 if (!data->no_disconnect_req) {
230 * Ignore write errors; there's nothing we can do,
231 * since we're about to close the pipe anyway. And the
232 * most likely error is EPIPE due to the helper dying
233 * to report an error itself.
235 sigchain_push(SIGPIPE, SIG_IGN);
236 xwrite(data->helper->in, "\n", 1);
237 sigchain_pop(SIGPIPE);
239 close(data->helper->in);
240 close(data->helper->out);
241 fclose(data->out);
242 res = finish_command(data->helper);
243 free(data->helper);
244 data->helper = NULL;
246 return res;
249 static const char *unsupported_options[] = {
250 TRANS_OPT_UPLOADPACK,
251 TRANS_OPT_RECEIVEPACK,
252 TRANS_OPT_THIN,
253 TRANS_OPT_KEEP
256 static const char *boolean_options[] = {
257 TRANS_OPT_THIN,
258 TRANS_OPT_KEEP,
259 TRANS_OPT_FOLLOWTAGS,
260 TRANS_OPT_PUSH_CERT
263 static int set_helper_option(struct transport *transport,
264 const char *name, const char *value)
266 struct helper_data *data = transport->data;
267 struct strbuf buf = STRBUF_INIT;
268 int i, ret, is_bool = 0;
270 get_helper(transport);
272 if (!data->option)
273 return 1;
275 for (i = 0; i < ARRAY_SIZE(unsupported_options); i++) {
276 if (!strcmp(name, unsupported_options[i]))
277 return 1;
280 for (i = 0; i < ARRAY_SIZE(boolean_options); i++) {
281 if (!strcmp(name, boolean_options[i])) {
282 is_bool = 1;
283 break;
287 strbuf_addf(&buf, "option %s ", name);
288 if (is_bool)
289 strbuf_addstr(&buf, value ? "true" : "false");
290 else
291 quote_c_style(value, &buf, NULL, 0);
292 strbuf_addch(&buf, '\n');
294 sendline(data, &buf);
295 if (recvline(data, &buf))
296 exit(128);
298 if (!strcmp(buf.buf, "ok"))
299 ret = 0;
300 else if (starts_with(buf.buf, "error")) {
301 ret = -1;
302 } else if (!strcmp(buf.buf, "unsupported"))
303 ret = 1;
304 else {
305 warning("%s unexpectedly said: '%s'", data->name, buf.buf);
306 ret = 1;
308 strbuf_release(&buf);
309 return ret;
312 static void standard_options(struct transport *t)
314 char buf[16];
315 int n;
316 int v = t->verbose;
318 set_helper_option(t, "progress", t->progress ? "true" : "false");
320 n = snprintf(buf, sizeof(buf), "%d", v + 1);
321 if (n >= sizeof(buf))
322 die("impossibly large verbosity value");
323 set_helper_option(t, "verbosity", buf);
326 static int release_helper(struct transport *transport)
328 int res = 0;
329 struct helper_data *data = transport->data;
330 free_refspec(data->refspec_nr, data->refspecs);
331 data->refspecs = NULL;
332 res = disconnect_helper(transport);
333 free(transport->data);
334 return res;
337 static int fetch_with_fetch(struct transport *transport,
338 int nr_heads, struct ref **to_fetch)
340 struct helper_data *data = transport->data;
341 int i;
342 struct strbuf buf = STRBUF_INIT;
344 for (i = 0; i < nr_heads; i++) {
345 const struct ref *posn = to_fetch[i];
346 if (posn->status & REF_STATUS_UPTODATE)
347 continue;
349 strbuf_addf(&buf, "fetch %s %s\n",
350 sha1_to_hex(posn->old_sha1),
351 posn->symref ? posn->symref : posn->name);
354 strbuf_addch(&buf, '\n');
355 sendline(data, &buf);
357 while (1) {
358 if (recvline(data, &buf))
359 exit(128);
361 if (starts_with(buf.buf, "lock ")) {
362 const char *name = buf.buf + 5;
363 if (transport->pack_lockfile)
364 warning("%s also locked %s", data->name, name);
365 else
366 transport->pack_lockfile = xstrdup(name);
368 else if (data->check_connectivity &&
369 data->transport_options.check_self_contained_and_connected &&
370 !strcmp(buf.buf, "connectivity-ok"))
371 data->transport_options.self_contained_and_connected = 1;
372 else if (!buf.len)
373 break;
374 else
375 warning("%s unexpectedly said: '%s'", data->name, buf.buf);
377 strbuf_release(&buf);
378 return 0;
381 static int get_importer(struct transport *transport, struct child_process *fastimport)
383 struct child_process *helper = get_helper(transport);
384 struct helper_data *data = transport->data;
385 int cat_blob_fd, code;
386 child_process_init(fastimport);
387 fastimport->in = helper->out;
388 argv_array_push(&fastimport->args, "fast-import");
389 argv_array_push(&fastimport->args, debug ? "--stats" : "--quiet");
391 if (data->bidi_import) {
392 cat_blob_fd = xdup(helper->in);
393 argv_array_pushf(&fastimport->args, "--cat-blob-fd=%d", cat_blob_fd);
395 fastimport->git_cmd = 1;
397 code = start_command(fastimport);
398 return code;
401 static int get_exporter(struct transport *transport,
402 struct child_process *fastexport,
403 struct string_list *revlist_args)
405 struct helper_data *data = transport->data;
406 struct child_process *helper = get_helper(transport);
407 int i;
409 child_process_init(fastexport);
411 /* we need to duplicate helper->in because we want to use it after
412 * fastexport is done with it. */
413 fastexport->out = dup(helper->in);
414 argv_array_push(&fastexport->args, "fast-export");
415 argv_array_push(&fastexport->args, "--use-done-feature");
416 argv_array_push(&fastexport->args, data->signed_tags ?
417 "--signed-tags=verbatim" : "--signed-tags=warn-strip");
418 if (data->export_marks)
419 argv_array_pushf(&fastexport->args, "--export-marks=%s.tmp", data->export_marks);
420 if (data->import_marks)
421 argv_array_pushf(&fastexport->args, "--import-marks=%s", data->import_marks);
423 for (i = 0; i < revlist_args->nr; i++)
424 argv_array_push(&fastexport->args, revlist_args->items[i].string);
426 fastexport->git_cmd = 1;
427 return start_command(fastexport);
430 static int fetch_with_import(struct transport *transport,
431 int nr_heads, struct ref **to_fetch)
433 struct child_process fastimport;
434 struct helper_data *data = transport->data;
435 int i;
436 struct ref *posn;
437 struct strbuf buf = STRBUF_INIT;
439 get_helper(transport);
441 if (get_importer(transport, &fastimport))
442 die("Couldn't run fast-import");
444 for (i = 0; i < nr_heads; i++) {
445 posn = to_fetch[i];
446 if (posn->status & REF_STATUS_UPTODATE)
447 continue;
449 strbuf_addf(&buf, "import %s\n",
450 posn->symref ? posn->symref : posn->name);
451 sendline(data, &buf);
452 strbuf_reset(&buf);
455 write_constant(data->helper->in, "\n");
457 * remote-helpers that advertise the bidi-import capability are required to
458 * buffer the complete batch of import commands until this newline before
459 * sending data to fast-import.
460 * These helpers read back data from fast-import on their stdin, which could
461 * be mixed with import commands, otherwise.
464 if (finish_command(&fastimport))
465 die("Error while running fast-import");
468 * The fast-import stream of a remote helper that advertises
469 * the "refspec" capability writes to the refs named after the
470 * right hand side of the first refspec matching each ref we
471 * were fetching.
473 * (If no "refspec" capability was specified, for historical
474 * reasons we default to the equivalent of *:*.)
476 * Store the result in to_fetch[i].old_sha1. Callers such
477 * as "git fetch" can use the value to write feedback to the
478 * terminal, populate FETCH_HEAD, and determine what new value
479 * should be written to peer_ref if the update is a
480 * fast-forward or this is a forced update.
482 for (i = 0; i < nr_heads; i++) {
483 char *private, *name;
484 posn = to_fetch[i];
485 if (posn->status & REF_STATUS_UPTODATE)
486 continue;
487 name = posn->symref ? posn->symref : posn->name;
488 if (data->refspecs)
489 private = apply_refspecs(data->refspecs, data->refspec_nr, name);
490 else
491 private = xstrdup(name);
492 if (private) {
493 read_ref(private, posn->old_sha1);
494 free(private);
497 strbuf_release(&buf);
498 return 0;
501 static int process_connect_service(struct transport *transport,
502 const char *name, const char *exec)
504 struct helper_data *data = transport->data;
505 struct strbuf cmdbuf = STRBUF_INIT;
506 struct child_process *helper;
507 int r, duped, ret = 0;
508 FILE *input;
510 helper = get_helper(transport);
513 * Yes, dup the pipe another time, as we need unbuffered version
514 * of input pipe as FILE*. fclose() closes the underlying fd and
515 * stream buffering only can be changed before first I/O operation
516 * on it.
518 duped = dup(helper->out);
519 if (duped < 0)
520 die_errno("Can't dup helper output fd");
521 input = xfdopen(duped, "r");
522 setvbuf(input, NULL, _IONBF, 0);
525 * Handle --upload-pack and friends. This is fire and forget...
526 * just warn if it fails.
528 if (strcmp(name, exec)) {
529 r = set_helper_option(transport, "servpath", exec);
530 if (r > 0)
531 warning("Setting remote service path not supported by protocol.");
532 else if (r < 0)
533 warning("Invalid remote service path.");
536 if (data->connect)
537 strbuf_addf(&cmdbuf, "connect %s\n", name);
538 else
539 goto exit;
541 sendline(data, &cmdbuf);
542 if (recvline_fh(input, &cmdbuf, name))
543 exit(128);
545 if (!strcmp(cmdbuf.buf, "")) {
546 data->no_disconnect_req = 1;
547 if (debug)
548 fprintf(stderr, "Debug: Smart transport connection "
549 "ready.\n");
550 ret = 1;
551 } else if (!strcmp(cmdbuf.buf, "fallback")) {
552 if (debug)
553 fprintf(stderr, "Debug: Falling back to dumb "
554 "transport.\n");
555 } else
556 die("Unknown response to connect: %s",
557 cmdbuf.buf);
559 exit:
560 fclose(input);
561 return ret;
564 static int process_connect(struct transport *transport,
565 int for_push)
567 struct helper_data *data = transport->data;
568 const char *name;
569 const char *exec;
571 name = for_push ? "git-receive-pack" : "git-upload-pack";
572 if (for_push)
573 exec = data->transport_options.receivepack;
574 else
575 exec = data->transport_options.uploadpack;
577 return process_connect_service(transport, name, exec);
580 static int connect_helper(struct transport *transport, const char *name,
581 const char *exec, int fd[2])
583 struct helper_data *data = transport->data;
585 /* Get_helper so connect is inited. */
586 get_helper(transport);
587 if (!data->connect)
588 die("Operation not supported by protocol.");
590 if (!process_connect_service(transport, name, exec))
591 die("Can't connect to subservice %s.", name);
593 fd[0] = data->helper->out;
594 fd[1] = data->helper->in;
595 return 0;
598 static int fetch(struct transport *transport,
599 int nr_heads, struct ref **to_fetch)
601 struct helper_data *data = transport->data;
602 int i, count;
604 if (process_connect(transport, 0)) {
605 do_take_over(transport);
606 return transport->fetch(transport, nr_heads, to_fetch);
609 count = 0;
610 for (i = 0; i < nr_heads; i++)
611 if (!(to_fetch[i]->status & REF_STATUS_UPTODATE))
612 count++;
614 if (!count)
615 return 0;
617 if (data->check_connectivity &&
618 data->transport_options.check_self_contained_and_connected)
619 set_helper_option(transport, "check-connectivity", "true");
621 if (transport->cloning)
622 set_helper_option(transport, "cloning", "true");
624 if (data->transport_options.update_shallow)
625 set_helper_option(transport, "update-shallow", "true");
627 if (data->fetch)
628 return fetch_with_fetch(transport, nr_heads, to_fetch);
630 if (data->import)
631 return fetch_with_import(transport, nr_heads, to_fetch);
633 return -1;
636 static int push_update_ref_status(struct strbuf *buf,
637 struct ref **ref,
638 struct ref *remote_refs)
640 char *refname, *msg;
641 int status, forced = 0;
643 if (starts_with(buf->buf, "ok ")) {
644 status = REF_STATUS_OK;
645 refname = buf->buf + 3;
646 } else if (starts_with(buf->buf, "error ")) {
647 status = REF_STATUS_REMOTE_REJECT;
648 refname = buf->buf + 6;
649 } else
650 die("expected ok/error, helper said '%s'", buf->buf);
652 msg = strchr(refname, ' ');
653 if (msg) {
654 struct strbuf msg_buf = STRBUF_INIT;
655 const char *end;
657 *msg++ = '\0';
658 if (!unquote_c_style(&msg_buf, msg, &end))
659 msg = strbuf_detach(&msg_buf, NULL);
660 else
661 msg = xstrdup(msg);
662 strbuf_release(&msg_buf);
664 if (!strcmp(msg, "no match")) {
665 status = REF_STATUS_NONE;
666 free(msg);
667 msg = NULL;
669 else if (!strcmp(msg, "up to date")) {
670 status = REF_STATUS_UPTODATE;
671 free(msg);
672 msg = NULL;
674 else if (!strcmp(msg, "non-fast forward")) {
675 status = REF_STATUS_REJECT_NONFASTFORWARD;
676 free(msg);
677 msg = NULL;
679 else if (!strcmp(msg, "already exists")) {
680 status = REF_STATUS_REJECT_ALREADY_EXISTS;
681 free(msg);
682 msg = NULL;
684 else if (!strcmp(msg, "fetch first")) {
685 status = REF_STATUS_REJECT_FETCH_FIRST;
686 free(msg);
687 msg = NULL;
689 else if (!strcmp(msg, "needs force")) {
690 status = REF_STATUS_REJECT_NEEDS_FORCE;
691 free(msg);
692 msg = NULL;
694 else if (!strcmp(msg, "stale info")) {
695 status = REF_STATUS_REJECT_STALE;
696 free(msg);
697 msg = NULL;
699 else if (!strcmp(msg, "forced update")) {
700 forced = 1;
701 free(msg);
702 msg = NULL;
706 if (*ref)
707 *ref = find_ref_by_name(*ref, refname);
708 if (!*ref)
709 *ref = find_ref_by_name(remote_refs, refname);
710 if (!*ref) {
711 warning("helper reported unexpected status of %s", refname);
712 return 1;
715 if ((*ref)->status != REF_STATUS_NONE) {
717 * Earlier, the ref was marked not to be pushed, so ignore the ref
718 * status reported by the remote helper if the latter is 'no match'.
720 if (status == REF_STATUS_NONE)
721 return 1;
724 (*ref)->status = status;
725 (*ref)->forced_update |= forced;
726 (*ref)->remote_status = msg;
727 return !(status == REF_STATUS_OK);
730 static int push_update_refs_status(struct helper_data *data,
731 struct ref *remote_refs,
732 int flags)
734 struct strbuf buf = STRBUF_INIT;
735 struct ref *ref = remote_refs;
736 int ret = 0;
738 for (;;) {
739 char *private;
741 if (recvline(data, &buf)) {
742 ret = 1;
743 break;
746 if (!buf.len)
747 break;
749 if (push_update_ref_status(&buf, &ref, remote_refs))
750 continue;
752 if (flags & TRANSPORT_PUSH_DRY_RUN || !data->refspecs || data->no_private_update)
753 continue;
755 /* propagate back the update to the remote namespace */
756 private = apply_refspecs(data->refspecs, data->refspec_nr, ref->name);
757 if (!private)
758 continue;
759 update_ref("update by helper", private, ref->new_sha1, NULL, 0, 0);
760 free(private);
762 strbuf_release(&buf);
763 return ret;
766 static int push_refs_with_push(struct transport *transport,
767 struct ref *remote_refs, int flags)
769 int force_all = flags & TRANSPORT_PUSH_FORCE;
770 int mirror = flags & TRANSPORT_PUSH_MIRROR;
771 struct helper_data *data = transport->data;
772 struct strbuf buf = STRBUF_INIT;
773 struct ref *ref;
774 struct string_list cas_options = STRING_LIST_INIT_DUP;
775 struct string_list_item *cas_option;
777 get_helper(transport);
778 if (!data->push)
779 return 1;
781 for (ref = remote_refs; ref; ref = ref->next) {
782 if (!ref->peer_ref && !mirror)
783 continue;
785 /* Check for statuses set by set_ref_status_for_push() */
786 switch (ref->status) {
787 case REF_STATUS_REJECT_NONFASTFORWARD:
788 case REF_STATUS_REJECT_STALE:
789 case REF_STATUS_REJECT_ALREADY_EXISTS:
790 case REF_STATUS_UPTODATE:
791 continue;
792 default:
793 ; /* do nothing */
796 if (force_all)
797 ref->force = 1;
799 strbuf_addstr(&buf, "push ");
800 if (!ref->deletion) {
801 if (ref->force)
802 strbuf_addch(&buf, '+');
803 if (ref->peer_ref)
804 strbuf_addstr(&buf, ref->peer_ref->name);
805 else
806 strbuf_addstr(&buf, sha1_to_hex(ref->new_sha1));
808 strbuf_addch(&buf, ':');
809 strbuf_addstr(&buf, ref->name);
810 strbuf_addch(&buf, '\n');
813 * The "--force-with-lease" options without explicit
814 * values to expect have already been expanded into
815 * the ref->old_sha1_expect[] field; we can ignore
816 * transport->smart_options->cas altogether and instead
817 * can enumerate them from the refs.
819 if (ref->expect_old_sha1) {
820 struct strbuf cas = STRBUF_INIT;
821 strbuf_addf(&cas, "%s:%s",
822 ref->name, sha1_to_hex(ref->old_sha1_expect));
823 string_list_append(&cas_options, strbuf_detach(&cas, NULL));
826 if (buf.len == 0) {
827 string_list_clear(&cas_options, 0);
828 return 0;
831 for_each_string_list_item(cas_option, &cas_options)
832 set_helper_option(transport, "cas", cas_option->string);
834 if (flags & TRANSPORT_PUSH_DRY_RUN) {
835 if (set_helper_option(transport, "dry-run", "true") != 0)
836 die("helper %s does not support dry-run", data->name);
837 } else if (flags & TRANSPORT_PUSH_CERT) {
838 if (set_helper_option(transport, TRANS_OPT_PUSH_CERT, "true") != 0)
839 die("helper %s does not support --signed", data->name);
842 strbuf_addch(&buf, '\n');
843 sendline(data, &buf);
844 strbuf_release(&buf);
846 return push_update_refs_status(data, remote_refs, flags);
849 static int push_refs_with_export(struct transport *transport,
850 struct ref *remote_refs, int flags)
852 struct ref *ref;
853 struct child_process *helper, exporter;
854 struct helper_data *data = transport->data;
855 struct string_list revlist_args = STRING_LIST_INIT_DUP;
856 struct strbuf buf = STRBUF_INIT;
858 if (!data->refspecs)
859 die("remote-helper doesn't support push; refspec needed");
861 if (flags & TRANSPORT_PUSH_DRY_RUN) {
862 if (set_helper_option(transport, "dry-run", "true") != 0)
863 die("helper %s does not support dry-run", data->name);
864 } else if (flags & TRANSPORT_PUSH_CERT) {
865 if (set_helper_option(transport, TRANS_OPT_PUSH_CERT, "true") != 0)
866 die("helper %s does not support --signed", data->name);
869 if (flags & TRANSPORT_PUSH_FORCE) {
870 if (set_helper_option(transport, "force", "true") != 0)
871 warning("helper %s does not support 'force'", data->name);
874 helper = get_helper(transport);
876 write_constant(helper->in, "export\n");
878 for (ref = remote_refs; ref; ref = ref->next) {
879 char *private;
880 unsigned char sha1[20];
882 private = apply_refspecs(data->refspecs, data->refspec_nr, ref->name);
883 if (private && !get_sha1(private, sha1)) {
884 strbuf_addf(&buf, "^%s", private);
885 string_list_append(&revlist_args, strbuf_detach(&buf, NULL));
886 hashcpy(ref->old_sha1, sha1);
888 free(private);
890 if (ref->peer_ref) {
891 if (strcmp(ref->name, ref->peer_ref->name)) {
892 if (!ref->deletion) {
893 const char *name;
894 int flag;
896 /* Follow symbolic refs (mainly for HEAD). */
897 name = resolve_ref_unsafe(
898 ref->peer_ref->name,
899 RESOLVE_REF_READING,
900 sha1, &flag);
901 if (!name || !(flag & REF_ISSYMREF))
902 name = ref->peer_ref->name;
904 strbuf_addf(&buf, "%s:%s", name, ref->name);
905 } else
906 strbuf_addf(&buf, ":%s", ref->name);
908 string_list_append(&revlist_args, "--refspec");
909 string_list_append(&revlist_args, buf.buf);
910 strbuf_release(&buf);
912 if (!ref->deletion)
913 string_list_append(&revlist_args, ref->peer_ref->name);
917 if (get_exporter(transport, &exporter, &revlist_args))
918 die("Couldn't run fast-export");
920 string_list_clear(&revlist_args, 1);
922 if (finish_command(&exporter))
923 die("Error while running fast-export");
924 if (push_update_refs_status(data, remote_refs, flags))
925 return 1;
927 if (data->export_marks) {
928 strbuf_addf(&buf, "%s.tmp", data->export_marks);
929 rename(buf.buf, data->export_marks);
930 strbuf_release(&buf);
933 return 0;
936 static int push_refs(struct transport *transport,
937 struct ref *remote_refs, int flags)
939 struct helper_data *data = transport->data;
941 if (process_connect(transport, 1)) {
942 do_take_over(transport);
943 return transport->push_refs(transport, remote_refs, flags);
946 if (!remote_refs) {
947 fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
948 "Perhaps you should specify a branch such as 'master'.\n");
949 return 0;
952 if (data->push)
953 return push_refs_with_push(transport, remote_refs, flags);
955 if (data->export)
956 return push_refs_with_export(transport, remote_refs, flags);
958 return -1;
962 static int has_attribute(const char *attrs, const char *attr) {
963 int len;
964 if (!attrs)
965 return 0;
967 len = strlen(attr);
968 for (;;) {
969 const char *space = strchrnul(attrs, ' ');
970 if (len == space - attrs && !strncmp(attrs, attr, len))
971 return 1;
972 if (!*space)
973 return 0;
974 attrs = space + 1;
978 static struct ref *get_refs_list(struct transport *transport, int for_push)
980 struct helper_data *data = transport->data;
981 struct child_process *helper;
982 struct ref *ret = NULL;
983 struct ref **tail = &ret;
984 struct ref *posn;
985 struct strbuf buf = STRBUF_INIT;
987 helper = get_helper(transport);
989 if (process_connect(transport, for_push)) {
990 do_take_over(transport);
991 return transport->get_refs_list(transport, for_push);
994 if (data->push && for_push)
995 write_str_in_full(helper->in, "list for-push\n");
996 else
997 write_str_in_full(helper->in, "list\n");
999 while (1) {
1000 char *eov, *eon;
1001 if (recvline(data, &buf))
1002 exit(128);
1004 if (!*buf.buf)
1005 break;
1007 eov = strchr(buf.buf, ' ');
1008 if (!eov)
1009 die("Malformed response in ref list: %s", buf.buf);
1010 eon = strchr(eov + 1, ' ');
1011 *eov = '\0';
1012 if (eon)
1013 *eon = '\0';
1014 *tail = alloc_ref(eov + 1);
1015 if (buf.buf[0] == '@')
1016 (*tail)->symref = xstrdup(buf.buf + 1);
1017 else if (buf.buf[0] != '?')
1018 get_sha1_hex(buf.buf, (*tail)->old_sha1);
1019 if (eon) {
1020 if (has_attribute(eon + 1, "unchanged")) {
1021 (*tail)->status |= REF_STATUS_UPTODATE;
1022 read_ref((*tail)->name, (*tail)->old_sha1);
1025 tail = &((*tail)->next);
1027 if (debug)
1028 fprintf(stderr, "Debug: Read ref listing.\n");
1029 strbuf_release(&buf);
1031 for (posn = ret; posn; posn = posn->next)
1032 resolve_remote_symref(posn, ret);
1034 return ret;
1037 int transport_helper_init(struct transport *transport, const char *name)
1039 struct helper_data *data = xcalloc(1, sizeof(*data));
1040 data->name = name;
1042 if (getenv("GIT_TRANSPORT_HELPER_DEBUG"))
1043 debug = 1;
1045 transport->data = data;
1046 transport->set_option = set_helper_option;
1047 transport->get_refs_list = get_refs_list;
1048 transport->fetch = fetch;
1049 transport->push_refs = push_refs;
1050 transport->disconnect = release_helper;
1051 transport->connect = connect_helper;
1052 transport->smart_options = &(data->transport_options);
1053 return 0;
1057 * Linux pipes can buffer 65536 bytes at once (and most platforms can
1058 * buffer less), so attempt reads and writes with up to that size.
1060 #define BUFFERSIZE 65536
1061 /* This should be enough to hold debugging message. */
1062 #define PBUFFERSIZE 8192
1064 /* Print bidirectional transfer loop debug message. */
1065 __attribute__((format (printf, 1, 2)))
1066 static void transfer_debug(const char *fmt, ...)
1068 va_list args;
1069 char msgbuf[PBUFFERSIZE];
1070 static int debug_enabled = -1;
1072 if (debug_enabled < 0)
1073 debug_enabled = getenv("GIT_TRANSLOOP_DEBUG") ? 1 : 0;
1074 if (!debug_enabled)
1075 return;
1077 va_start(args, fmt);
1078 vsnprintf(msgbuf, PBUFFERSIZE, fmt, args);
1079 va_end(args);
1080 fprintf(stderr, "Transfer loop debugging: %s\n", msgbuf);
1083 /* Stream state: More data may be coming in this direction. */
1084 #define SSTATE_TRANSFERING 0
1086 * Stream state: No more data coming in this direction, flushing rest of
1087 * data.
1089 #define SSTATE_FLUSHING 1
1090 /* Stream state: Transfer in this direction finished. */
1091 #define SSTATE_FINISHED 2
1093 #define STATE_NEEDS_READING(state) ((state) <= SSTATE_TRANSFERING)
1094 #define STATE_NEEDS_WRITING(state) ((state) <= SSTATE_FLUSHING)
1095 #define STATE_NEEDS_CLOSING(state) ((state) == SSTATE_FLUSHING)
1097 /* Unidirectional transfer. */
1098 struct unidirectional_transfer {
1099 /* Source */
1100 int src;
1101 /* Destination */
1102 int dest;
1103 /* Is source socket? */
1104 int src_is_sock;
1105 /* Is destination socket? */
1106 int dest_is_sock;
1107 /* Transfer state (TRANSFERRING/FLUSHING/FINISHED) */
1108 int state;
1109 /* Buffer. */
1110 char buf[BUFFERSIZE];
1111 /* Buffer used. */
1112 size_t bufuse;
1113 /* Name of source. */
1114 const char *src_name;
1115 /* Name of destination. */
1116 const char *dest_name;
1119 /* Closes the target (for writing) if transfer has finished. */
1120 static void udt_close_if_finished(struct unidirectional_transfer *t)
1122 if (STATE_NEEDS_CLOSING(t->state) && !t->bufuse) {
1123 t->state = SSTATE_FINISHED;
1124 if (t->dest_is_sock)
1125 shutdown(t->dest, SHUT_WR);
1126 else
1127 close(t->dest);
1128 transfer_debug("Closed %s.", t->dest_name);
1133 * Tries to read read data from source into buffer. If buffer is full,
1134 * no data is read. Returns 0 on success, -1 on error.
1136 static int udt_do_read(struct unidirectional_transfer *t)
1138 ssize_t bytes;
1140 if (t->bufuse == BUFFERSIZE)
1141 return 0; /* No space for more. */
1143 transfer_debug("%s is readable", t->src_name);
1144 bytes = read(t->src, t->buf + t->bufuse, BUFFERSIZE - t->bufuse);
1145 if (bytes < 0 && errno != EWOULDBLOCK && errno != EAGAIN &&
1146 errno != EINTR) {
1147 error("read(%s) failed: %s", t->src_name, strerror(errno));
1148 return -1;
1149 } else if (bytes == 0) {
1150 transfer_debug("%s EOF (with %i bytes in buffer)",
1151 t->src_name, (int)t->bufuse);
1152 t->state = SSTATE_FLUSHING;
1153 } else if (bytes > 0) {
1154 t->bufuse += bytes;
1155 transfer_debug("Read %i bytes from %s (buffer now at %i)",
1156 (int)bytes, t->src_name, (int)t->bufuse);
1158 return 0;
1161 /* Tries to write data from buffer into destination. If buffer is empty,
1162 * no data is written. Returns 0 on success, -1 on error.
1164 static int udt_do_write(struct unidirectional_transfer *t)
1166 ssize_t bytes;
1168 if (t->bufuse == 0)
1169 return 0; /* Nothing to write. */
1171 transfer_debug("%s is writable", t->dest_name);
1172 bytes = xwrite(t->dest, t->buf, t->bufuse);
1173 if (bytes < 0 && errno != EWOULDBLOCK) {
1174 error("write(%s) failed: %s", t->dest_name, strerror(errno));
1175 return -1;
1176 } else if (bytes > 0) {
1177 t->bufuse -= bytes;
1178 if (t->bufuse)
1179 memmove(t->buf, t->buf + bytes, t->bufuse);
1180 transfer_debug("Wrote %i bytes to %s (buffer now at %i)",
1181 (int)bytes, t->dest_name, (int)t->bufuse);
1183 return 0;
1187 /* State of bidirectional transfer loop. */
1188 struct bidirectional_transfer_state {
1189 /* Direction from program to git. */
1190 struct unidirectional_transfer ptg;
1191 /* Direction from git to program. */
1192 struct unidirectional_transfer gtp;
1195 static void *udt_copy_task_routine(void *udt)
1197 struct unidirectional_transfer *t = (struct unidirectional_transfer *)udt;
1198 while (t->state != SSTATE_FINISHED) {
1199 if (STATE_NEEDS_READING(t->state))
1200 if (udt_do_read(t))
1201 return NULL;
1202 if (STATE_NEEDS_WRITING(t->state))
1203 if (udt_do_write(t))
1204 return NULL;
1205 if (STATE_NEEDS_CLOSING(t->state))
1206 udt_close_if_finished(t);
1208 return udt; /* Just some non-NULL value. */
1211 #ifndef NO_PTHREADS
1214 * Join thread, with appropriate errors on failure. Name is name for the
1215 * thread (for error messages). Returns 0 on success, 1 on failure.
1217 static int tloop_join(pthread_t thread, const char *name)
1219 int err;
1220 void *tret;
1221 err = pthread_join(thread, &tret);
1222 if (!tret) {
1223 error("%s thread failed", name);
1224 return 1;
1226 if (err) {
1227 error("%s thread failed to join: %s", name, strerror(err));
1228 return 1;
1230 return 0;
1234 * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1235 * -1 on failure.
1237 static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1239 pthread_t gtp_thread;
1240 pthread_t ptg_thread;
1241 int err;
1242 int ret = 0;
1243 err = pthread_create(&gtp_thread, NULL, udt_copy_task_routine,
1244 &s->gtp);
1245 if (err)
1246 die("Can't start thread for copying data: %s", strerror(err));
1247 err = pthread_create(&ptg_thread, NULL, udt_copy_task_routine,
1248 &s->ptg);
1249 if (err)
1250 die("Can't start thread for copying data: %s", strerror(err));
1252 ret |= tloop_join(gtp_thread, "Git to program copy");
1253 ret |= tloop_join(ptg_thread, "Program to git copy");
1254 return ret;
1256 #else
1258 /* Close the source and target (for writing) for transfer. */
1259 static void udt_kill_transfer(struct unidirectional_transfer *t)
1261 t->state = SSTATE_FINISHED;
1263 * Socket read end left open isn't a disaster if nobody
1264 * attempts to read from it (mingw compat headers do not
1265 * have SHUT_RD)...
1267 * We can't fully close the socket since otherwise gtp
1268 * task would first close the socket it sends data to
1269 * while closing the ptg file descriptors.
1271 if (!t->src_is_sock)
1272 close(t->src);
1273 if (t->dest_is_sock)
1274 shutdown(t->dest, SHUT_WR);
1275 else
1276 close(t->dest);
1280 * Join process, with appropriate errors on failure. Name is name for the
1281 * process (for error messages). Returns 0 on success, 1 on failure.
1283 static int tloop_join(pid_t pid, const char *name)
1285 int tret;
1286 if (waitpid(pid, &tret, 0) < 0) {
1287 error("%s process failed to wait: %s", name, strerror(errno));
1288 return 1;
1290 if (!WIFEXITED(tret) || WEXITSTATUS(tret)) {
1291 error("%s process failed", name);
1292 return 1;
1294 return 0;
1298 * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1299 * -1 on failure.
1301 static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1303 pid_t pid1, pid2;
1304 int ret = 0;
1306 /* Fork thread #1: git to program. */
1307 pid1 = fork();
1308 if (pid1 < 0)
1309 die_errno("Can't start thread for copying data");
1310 else if (pid1 == 0) {
1311 udt_kill_transfer(&s->ptg);
1312 exit(udt_copy_task_routine(&s->gtp) ? 0 : 1);
1315 /* Fork thread #2: program to git. */
1316 pid2 = fork();
1317 if (pid2 < 0)
1318 die_errno("Can't start thread for copying data");
1319 else if (pid2 == 0) {
1320 udt_kill_transfer(&s->gtp);
1321 exit(udt_copy_task_routine(&s->ptg) ? 0 : 1);
1325 * Close both streams in parent as to not interfere with
1326 * end of file detection and wait for both tasks to finish.
1328 udt_kill_transfer(&s->gtp);
1329 udt_kill_transfer(&s->ptg);
1330 ret |= tloop_join(pid1, "Git to program copy");
1331 ret |= tloop_join(pid2, "Program to git copy");
1332 return ret;
1334 #endif
1337 * Copies data from stdin to output and from input to stdout simultaneously.
1338 * Additionally filtering through given filter. If filter is NULL, uses
1339 * identity filter.
1341 int bidirectional_transfer_loop(int input, int output)
1343 struct bidirectional_transfer_state state;
1345 /* Fill the state fields. */
1346 state.ptg.src = input;
1347 state.ptg.dest = 1;
1348 state.ptg.src_is_sock = (input == output);
1349 state.ptg.dest_is_sock = 0;
1350 state.ptg.state = SSTATE_TRANSFERING;
1351 state.ptg.bufuse = 0;
1352 state.ptg.src_name = "remote input";
1353 state.ptg.dest_name = "stdout";
1355 state.gtp.src = 0;
1356 state.gtp.dest = output;
1357 state.gtp.src_is_sock = 0;
1358 state.gtp.dest_is_sock = (input == output);
1359 state.gtp.state = SSTATE_TRANSFERING;
1360 state.gtp.bufuse = 0;
1361 state.gtp.src_name = "stdin";
1362 state.gtp.dest_name = "remote output";
1364 return tloop_spawnwait_tasks(&state);