1#include "cache.h"
2#include "transport.h"
3#include "quote.h"
4#include "run-command.h"
5#include "commit.h"
6#include "diff.h"
7#include "revision.h"
8#include "remote.h"
9#include "string-list.h"
10#include "thread-utils.h"
11#include "sigchain.h"
12#include "argv-array.h"
13#include "refs.h"
14
15static int debug;
16
17struct 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).
39 */
40 struct git_transport_options transport_options;
41};
42
43static void sendline(struct helper_data *helper, struct strbuf *buffer)
44{
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");
50}
51
52static int recvline_fh(FILE *helper, struct strbuf *buffer, const char *name)
53{
54 strbuf_reset(buffer);
55 if (debug)
56 fprintf(stderr, "Debug: Remote helper: Waiting...\n");
57 if (strbuf_getline(buffer, helper) == EOF) {
58 if (debug)
59 fprintf(stderr, "Debug: Remote helper quit.\n");
60 return 1;
61 }
62
63 if (debug)
64 fprintf(stderr, "Debug: Remote helper: <- %s\n", buffer->buf);
65 return 0;
66}
67
68static int recvline(struct helper_data *helper, struct strbuf *buffer)
69{
70 return recvline_fh(helper->out, buffer, helper->name);
71}
72
73static void write_constant(int fd, const char *str)
74{
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");
79}
80
81static const char *remove_ext_force(const char *url)
82{
83 if (url) {
84 const char *colon = strchr(url, ':');
85 if (colon && colon[1] == ':')
86 return colon + 2;
87 }
88 return url;
89}
90
91static void do_take_over(struct transport *transport)
92{
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);
98}
99
100static void standard_options(struct transport *t);
101
102static struct child_process *get_helper(struct transport *transport)
103{
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;
112
113 if (data->helper)
114 return data->helper;
115
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;
126
127 argv_array_pushf(&helper->env_array, "%s=%s", GIT_DIR_ENVIRONMENT,
128 get_git_dir());
129
130 code = start_command(helper);
131 if (code < 0 && errno == ENOENT)
132 die("Unable to find remote helper for '%s'", data->name);
133 else if (code != 0)
134 exit(code);
135
136 data->helper = helper;
137 data->no_disconnect_req = 0;
138
139 /*
140 * Open the output as FILE* so strbuf_getline_*() family of
141 * functions can be used.
142 * Do this with duped fd because fclose() will close the fd,
143 * and stuff like taking over will require the fd to remain.
144 */
145 duped = dup(helper->out);
146 if (duped < 0)
147 die_errno("Can't dup helper output fd");
148 data->out = xfdopen(duped, "r");
149
150 write_constant(helper->in, "capabilities\n");
151
152 while (1) {
153 const char *capname, *arg;
154 int mandatory = 0;
155 if (recvline(data, &buf))
156 exit(128);
157
158 if (!*buf.buf)
159 break;
160
161 if (*buf.buf == '*') {
162 capname = buf.buf + 1;
163 mandatory = 1;
164 } else
165 capname = buf.buf;
166
167 if (debug)
168 fprintf(stderr, "Debug: Got cap %s\n", capname);
169 if (!strcmp(capname, "fetch"))
170 data->fetch = 1;
171 else if (!strcmp(capname, "option"))
172 data->option = 1;
173 else if (!strcmp(capname, "push"))
174 data->push = 1;
175 else if (!strcmp(capname, "import"))
176 data->import = 1;
177 else if (!strcmp(capname, "bidi-import"))
178 data->bidi_import = 1;
179 else if (!strcmp(capname, "export"))
180 data->export = 1;
181 else if (!strcmp(capname, "check-connectivity"))
182 data->check_connectivity = 1;
183 else if (!data->refspecs && skip_prefix(capname, "refspec ", &arg)) {
184 ALLOC_GROW(refspecs,
185 refspec_nr + 1,
186 refspec_alloc);
187 refspecs[refspec_nr++] = xstrdup(arg);
188 } else if (!strcmp(capname, "connect")) {
189 data->connect = 1;
190 } else if (!strcmp(capname, "signed-tags")) {
191 data->signed_tags = 1;
192 } else if (skip_prefix(capname, "export-marks ", &arg)) {
193 data->export_marks = xstrdup(arg);
194 } else if (skip_prefix(capname, "import-marks ", &arg)) {
195 data->import_marks = xstrdup(arg);
196 } else if (starts_with(capname, "no-private-update")) {
197 data->no_private_update = 1;
198 } else if (mandatory) {
199 die("Unknown mandatory capability %s. This remote "
200 "helper probably needs newer version of Git.",
201 capname);
202 }
203 }
204 if (refspecs) {
205 int i;
206 data->refspec_nr = refspec_nr;
207 data->refspecs = parse_fetch_refspec(refspec_nr, refspecs);
208 for (i = 0; i < refspec_nr; i++)
209 free((char *)refspecs[i]);
210 free(refspecs);
211 } else if (data->import || data->bidi_import || data->export) {
212 warning("This remote helper should implement refspec capability.");
213 }
214 strbuf_release(&buf);
215 if (debug)
216 fprintf(stderr, "Debug: Capabilities complete.\n");
217 standard_options(transport);
218 return data->helper;
219}
220
221static int disconnect_helper(struct transport *transport)
222{
223 struct helper_data *data = transport->data;
224 int res = 0;
225
226 if (data->helper) {
227 if (debug)
228 fprintf(stderr, "Debug: Disconnecting.\n");
229 if (!data->no_disconnect_req) {
230 /*
231 * Ignore write errors; there's nothing we can do,
232 * since we're about to close the pipe anyway. And the
233 * most likely error is EPIPE due to the helper dying
234 * to report an error itself.
235 */
236 sigchain_push(SIGPIPE, SIG_IGN);
237 xwrite(data->helper->in, "\n", 1);
238 sigchain_pop(SIGPIPE);
239 }
240 close(data->helper->in);
241 close(data->helper->out);
242 fclose(data->out);
243 res = finish_command(data->helper);
244 free(data->helper);
245 data->helper = NULL;
246 }
247 return res;
248}
249
250static const char *unsupported_options[] = {
251 TRANS_OPT_UPLOADPACK,
252 TRANS_OPT_RECEIVEPACK,
253 TRANS_OPT_THIN,
254 TRANS_OPT_KEEP
255 };
256
257static const char *boolean_options[] = {
258 TRANS_OPT_THIN,
259 TRANS_OPT_KEEP,
260 TRANS_OPT_FOLLOWTAGS,
261 };
262
263static int set_helper_option(struct transport *transport,
264 const char *name, const char *value)
265{
266 struct helper_data *data = transport->data;
267 struct strbuf buf = STRBUF_INIT;
268 int i, ret, is_bool = 0;
269
270 get_helper(transport);
271
272 if (!data->option)
273 return 1;
274
275 for (i = 0; i < ARRAY_SIZE(unsupported_options); i++) {
276 if (!strcmp(name, unsupported_options[i]))
277 return 1;
278 }
279
280 for (i = 0; i < ARRAY_SIZE(boolean_options); i++) {
281 if (!strcmp(name, boolean_options[i])) {
282 is_bool = 1;
283 break;
284 }
285 }
286
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');
293
294 sendline(data, &buf);
295 if (recvline(data, &buf))
296 exit(128);
297
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;
307 }
308 strbuf_release(&buf);
309 return ret;
310}
311
312static void standard_options(struct transport *t)
313{
314 char buf[16];
315 int n;
316 int v = t->verbose;
317
318 set_helper_option(t, "progress", t->progress ? "true" : "false");
319
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);
324
325 switch (t->family) {
326 case TRANSPORT_FAMILY_ALL:
327 /*
328 * this is already the default,
329 * do not break old remote helpers by setting "all" here
330 */
331 break;
332 case TRANSPORT_FAMILY_IPV4:
333 set_helper_option(t, "family", "ipv4");
334 break;
335 case TRANSPORT_FAMILY_IPV6:
336 set_helper_option(t, "family", "ipv6");
337 break;
338 }
339}
340
341static int release_helper(struct transport *transport)
342{
343 int res = 0;
344 struct helper_data *data = transport->data;
345 free_refspec(data->refspec_nr, data->refspecs);
346 data->refspecs = NULL;
347 res = disconnect_helper(transport);
348 free(transport->data);
349 return res;
350}
351
352static int fetch_with_fetch(struct transport *transport,
353 int nr_heads, struct ref **to_fetch)
354{
355 struct helper_data *data = transport->data;
356 int i;
357 struct strbuf buf = STRBUF_INIT;
358
359 for (i = 0; i < nr_heads; i++) {
360 const struct ref *posn = to_fetch[i];
361 if (posn->status & REF_STATUS_UPTODATE)
362 continue;
363
364 strbuf_addf(&buf, "fetch %s %s\n",
365 oid_to_hex(&posn->old_oid),
366 posn->symref ? posn->symref : posn->name);
367 }
368
369 strbuf_addch(&buf, '\n');
370 sendline(data, &buf);
371
372 while (1) {
373 if (recvline(data, &buf))
374 exit(128);
375
376 if (starts_with(buf.buf, "lock ")) {
377 const char *name = buf.buf + 5;
378 if (transport->pack_lockfile)
379 warning("%s also locked %s", data->name, name);
380 else
381 transport->pack_lockfile = xstrdup(name);
382 }
383 else if (data->check_connectivity &&
384 data->transport_options.check_self_contained_and_connected &&
385 !strcmp(buf.buf, "connectivity-ok"))
386 data->transport_options.self_contained_and_connected = 1;
387 else if (!buf.len)
388 break;
389 else
390 warning("%s unexpectedly said: '%s'", data->name, buf.buf);
391 }
392 strbuf_release(&buf);
393 return 0;
394}
395
396static int get_importer(struct transport *transport, struct child_process *fastimport)
397{
398 struct child_process *helper = get_helper(transport);
399 struct helper_data *data = transport->data;
400 int cat_blob_fd, code;
401 child_process_init(fastimport);
402 fastimport->in = helper->out;
403 argv_array_push(&fastimport->args, "fast-import");
404 argv_array_push(&fastimport->args, debug ? "--stats" : "--quiet");
405
406 if (data->bidi_import) {
407 cat_blob_fd = xdup(helper->in);
408 argv_array_pushf(&fastimport->args, "--cat-blob-fd=%d", cat_blob_fd);
409 }
410 fastimport->git_cmd = 1;
411
412 code = start_command(fastimport);
413 return code;
414}
415
416static int get_exporter(struct transport *transport,
417 struct child_process *fastexport,
418 struct string_list *revlist_args)
419{
420 struct helper_data *data = transport->data;
421 struct child_process *helper = get_helper(transport);
422 int i;
423
424 child_process_init(fastexport);
425
426 /* we need to duplicate helper->in because we want to use it after
427 * fastexport is done with it. */
428 fastexport->out = dup(helper->in);
429 argv_array_push(&fastexport->args, "fast-export");
430 argv_array_push(&fastexport->args, "--use-done-feature");
431 argv_array_push(&fastexport->args, data->signed_tags ?
432 "--signed-tags=verbatim" : "--signed-tags=warn-strip");
433 if (data->export_marks)
434 argv_array_pushf(&fastexport->args, "--export-marks=%s.tmp", data->export_marks);
435 if (data->import_marks)
436 argv_array_pushf(&fastexport->args, "--import-marks=%s", data->import_marks);
437
438 for (i = 0; i < revlist_args->nr; i++)
439 argv_array_push(&fastexport->args, revlist_args->items[i].string);
440
441 fastexport->git_cmd = 1;
442 return start_command(fastexport);
443}
444
445static int fetch_with_import(struct transport *transport,
446 int nr_heads, struct ref **to_fetch)
447{
448 struct child_process fastimport;
449 struct helper_data *data = transport->data;
450 int i;
451 struct ref *posn;
452 struct strbuf buf = STRBUF_INIT;
453
454 get_helper(transport);
455
456 if (get_importer(transport, &fastimport))
457 die("Couldn't run fast-import");
458
459 for (i = 0; i < nr_heads; i++) {
460 posn = to_fetch[i];
461 if (posn->status & REF_STATUS_UPTODATE)
462 continue;
463
464 strbuf_addf(&buf, "import %s\n",
465 posn->symref ? posn->symref : posn->name);
466 sendline(data, &buf);
467 strbuf_reset(&buf);
468 }
469
470 write_constant(data->helper->in, "\n");
471 /*
472 * remote-helpers that advertise the bidi-import capability are required to
473 * buffer the complete batch of import commands until this newline before
474 * sending data to fast-import.
475 * These helpers read back data from fast-import on their stdin, which could
476 * be mixed with import commands, otherwise.
477 */
478
479 if (finish_command(&fastimport))
480 die("Error while running fast-import");
481
482 /*
483 * The fast-import stream of a remote helper that advertises
484 * the "refspec" capability writes to the refs named after the
485 * right hand side of the first refspec matching each ref we
486 * were fetching.
487 *
488 * (If no "refspec" capability was specified, for historical
489 * reasons we default to the equivalent of *:*.)
490 *
491 * Store the result in to_fetch[i].old_sha1. Callers such
492 * as "git fetch" can use the value to write feedback to the
493 * terminal, populate FETCH_HEAD, and determine what new value
494 * should be written to peer_ref if the update is a
495 * fast-forward or this is a forced update.
496 */
497 for (i = 0; i < nr_heads; i++) {
498 char *private, *name;
499 posn = to_fetch[i];
500 if (posn->status & REF_STATUS_UPTODATE)
501 continue;
502 name = posn->symref ? posn->symref : posn->name;
503 if (data->refspecs)
504 private = apply_refspecs(data->refspecs, data->refspec_nr, name);
505 else
506 private = xstrdup(name);
507 if (private) {
508 if (read_ref(private, posn->old_oid.hash) < 0)
509 die("Could not read ref %s", private);
510 free(private);
511 }
512 }
513 strbuf_release(&buf);
514 return 0;
515}
516
517static int process_connect_service(struct transport *transport,
518 const char *name, const char *exec)
519{
520 struct helper_data *data = transport->data;
521 struct strbuf cmdbuf = STRBUF_INIT;
522 struct child_process *helper;
523 int r, duped, ret = 0;
524 FILE *input;
525
526 helper = get_helper(transport);
527
528 /*
529 * Yes, dup the pipe another time, as we need unbuffered version
530 * of input pipe as FILE*. fclose() closes the underlying fd and
531 * stream buffering only can be changed before first I/O operation
532 * on it.
533 */
534 duped = dup(helper->out);
535 if (duped < 0)
536 die_errno("Can't dup helper output fd");
537 input = xfdopen(duped, "r");
538 setvbuf(input, NULL, _IONBF, 0);
539
540 /*
541 * Handle --upload-pack and friends. This is fire and forget...
542 * just warn if it fails.
543 */
544 if (strcmp(name, exec)) {
545 r = set_helper_option(transport, "servpath", exec);
546 if (r > 0)
547 warning("Setting remote service path not supported by protocol.");
548 else if (r < 0)
549 warning("Invalid remote service path.");
550 }
551
552 if (data->connect)
553 strbuf_addf(&cmdbuf, "connect %s\n", name);
554 else
555 goto exit;
556
557 sendline(data, &cmdbuf);
558 if (recvline_fh(input, &cmdbuf, name))
559 exit(128);
560
561 if (!strcmp(cmdbuf.buf, "")) {
562 data->no_disconnect_req = 1;
563 if (debug)
564 fprintf(stderr, "Debug: Smart transport connection "
565 "ready.\n");
566 ret = 1;
567 } else if (!strcmp(cmdbuf.buf, "fallback")) {
568 if (debug)
569 fprintf(stderr, "Debug: Falling back to dumb "
570 "transport.\n");
571 } else
572 die("Unknown response to connect: %s",
573 cmdbuf.buf);
574
575exit:
576 fclose(input);
577 return ret;
578}
579
580static int process_connect(struct transport *transport,
581 int for_push)
582{
583 struct helper_data *data = transport->data;
584 const char *name;
585 const char *exec;
586
587 name = for_push ? "git-receive-pack" : "git-upload-pack";
588 if (for_push)
589 exec = data->transport_options.receivepack;
590 else
591 exec = data->transport_options.uploadpack;
592
593 return process_connect_service(transport, name, exec);
594}
595
596static int connect_helper(struct transport *transport, const char *name,
597 const char *exec, int fd[2])
598{
599 struct helper_data *data = transport->data;
600
601 /* Get_helper so connect is inited. */
602 get_helper(transport);
603 if (!data->connect)
604 die("Operation not supported by protocol.");
605
606 if (!process_connect_service(transport, name, exec))
607 die("Can't connect to subservice %s.", name);
608
609 fd[0] = data->helper->out;
610 fd[1] = data->helper->in;
611 return 0;
612}
613
614static int fetch(struct transport *transport,
615 int nr_heads, struct ref **to_fetch)
616{
617 struct helper_data *data = transport->data;
618 int i, count;
619
620 if (process_connect(transport, 0)) {
621 do_take_over(transport);
622 return transport->fetch(transport, nr_heads, to_fetch);
623 }
624
625 count = 0;
626 for (i = 0; i < nr_heads; i++)
627 if (!(to_fetch[i]->status & REF_STATUS_UPTODATE))
628 count++;
629
630 if (!count)
631 return 0;
632
633 if (data->check_connectivity &&
634 data->transport_options.check_self_contained_and_connected)
635 set_helper_option(transport, "check-connectivity", "true");
636
637 if (transport->cloning)
638 set_helper_option(transport, "cloning", "true");
639
640 if (data->transport_options.update_shallow)
641 set_helper_option(transport, "update-shallow", "true");
642
643 if (data->fetch)
644 return fetch_with_fetch(transport, nr_heads, to_fetch);
645
646 if (data->import)
647 return fetch_with_import(transport, nr_heads, to_fetch);
648
649 return -1;
650}
651
652static int push_update_ref_status(struct strbuf *buf,
653 struct ref **ref,
654 struct ref *remote_refs)
655{
656 char *refname, *msg;
657 int status, forced = 0;
658
659 if (starts_with(buf->buf, "ok ")) {
660 status = REF_STATUS_OK;
661 refname = buf->buf + 3;
662 } else if (starts_with(buf->buf, "error ")) {
663 status = REF_STATUS_REMOTE_REJECT;
664 refname = buf->buf + 6;
665 } else
666 die("expected ok/error, helper said '%s'", buf->buf);
667
668 msg = strchr(refname, ' ');
669 if (msg) {
670 struct strbuf msg_buf = STRBUF_INIT;
671 const char *end;
672
673 *msg++ = '\0';
674 if (!unquote_c_style(&msg_buf, msg, &end))
675 msg = strbuf_detach(&msg_buf, NULL);
676 else
677 msg = xstrdup(msg);
678 strbuf_release(&msg_buf);
679
680 if (!strcmp(msg, "no match")) {
681 status = REF_STATUS_NONE;
682 free(msg);
683 msg = NULL;
684 }
685 else if (!strcmp(msg, "up to date")) {
686 status = REF_STATUS_UPTODATE;
687 free(msg);
688 msg = NULL;
689 }
690 else if (!strcmp(msg, "non-fast forward")) {
691 status = REF_STATUS_REJECT_NONFASTFORWARD;
692 free(msg);
693 msg = NULL;
694 }
695 else if (!strcmp(msg, "already exists")) {
696 status = REF_STATUS_REJECT_ALREADY_EXISTS;
697 free(msg);
698 msg = NULL;
699 }
700 else if (!strcmp(msg, "fetch first")) {
701 status = REF_STATUS_REJECT_FETCH_FIRST;
702 free(msg);
703 msg = NULL;
704 }
705 else if (!strcmp(msg, "needs force")) {
706 status = REF_STATUS_REJECT_NEEDS_FORCE;
707 free(msg);
708 msg = NULL;
709 }
710 else if (!strcmp(msg, "stale info")) {
711 status = REF_STATUS_REJECT_STALE;
712 free(msg);
713 msg = NULL;
714 }
715 else if (!strcmp(msg, "forced update")) {
716 forced = 1;
717 free(msg);
718 msg = NULL;
719 }
720 }
721
722 if (*ref)
723 *ref = find_ref_by_name(*ref, refname);
724 if (!*ref)
725 *ref = find_ref_by_name(remote_refs, refname);
726 if (!*ref) {
727 warning("helper reported unexpected status of %s", refname);
728 return 1;
729 }
730
731 if ((*ref)->status != REF_STATUS_NONE) {
732 /*
733 * Earlier, the ref was marked not to be pushed, so ignore the ref
734 * status reported by the remote helper if the latter is 'no match'.
735 */
736 if (status == REF_STATUS_NONE)
737 return 1;
738 }
739
740 (*ref)->status = status;
741 (*ref)->forced_update |= forced;
742 (*ref)->remote_status = msg;
743 return !(status == REF_STATUS_OK);
744}
745
746static int push_update_refs_status(struct helper_data *data,
747 struct ref *remote_refs,
748 int flags)
749{
750 struct strbuf buf = STRBUF_INIT;
751 struct ref *ref = remote_refs;
752 int ret = 0;
753
754 for (;;) {
755 char *private;
756
757 if (recvline(data, &buf)) {
758 ret = 1;
759 break;
760 }
761
762 if (!buf.len)
763 break;
764
765 if (push_update_ref_status(&buf, &ref, remote_refs))
766 continue;
767
768 if (flags & TRANSPORT_PUSH_DRY_RUN || !data->refspecs || data->no_private_update)
769 continue;
770
771 /* propagate back the update to the remote namespace */
772 private = apply_refspecs(data->refspecs, data->refspec_nr, ref->name);
773 if (!private)
774 continue;
775 update_ref("update by helper", private, ref->new_oid.hash, NULL, 0, 0);
776 free(private);
777 }
778 strbuf_release(&buf);
779 return ret;
780}
781
782static void set_common_push_options(struct transport *transport,
783 const char *name, int flags)
784{
785 if (flags & TRANSPORT_PUSH_DRY_RUN) {
786 if (set_helper_option(transport, "dry-run", "true") != 0)
787 die("helper %s does not support dry-run", name);
788 } else if (flags & TRANSPORT_PUSH_CERT_ALWAYS) {
789 if (set_helper_option(transport, TRANS_OPT_PUSH_CERT, "true") != 0)
790 die("helper %s does not support --signed", name);
791 } else if (flags & TRANSPORT_PUSH_CERT_IF_ASKED) {
792 if (set_helper_option(transport, TRANS_OPT_PUSH_CERT, "if-asked") != 0)
793 die("helper %s does not support --signed=if-asked", name);
794 }
795}
796
797static int push_refs_with_push(struct transport *transport,
798 struct ref *remote_refs, int flags)
799{
800 int force_all = flags & TRANSPORT_PUSH_FORCE;
801 int mirror = flags & TRANSPORT_PUSH_MIRROR;
802 struct helper_data *data = transport->data;
803 struct strbuf buf = STRBUF_INIT;
804 struct ref *ref;
805 struct string_list cas_options = STRING_LIST_INIT_DUP;
806 struct string_list_item *cas_option;
807
808 get_helper(transport);
809 if (!data->push)
810 return 1;
811
812 for (ref = remote_refs; ref; ref = ref->next) {
813 if (!ref->peer_ref && !mirror)
814 continue;
815
816 /* Check for statuses set by set_ref_status_for_push() */
817 switch (ref->status) {
818 case REF_STATUS_REJECT_NONFASTFORWARD:
819 case REF_STATUS_REJECT_STALE:
820 case REF_STATUS_REJECT_ALREADY_EXISTS:
821 case REF_STATUS_UPTODATE:
822 continue;
823 default:
824 ; /* do nothing */
825 }
826
827 if (force_all)
828 ref->force = 1;
829
830 strbuf_addstr(&buf, "push ");
831 if (!ref->deletion) {
832 if (ref->force)
833 strbuf_addch(&buf, '+');
834 if (ref->peer_ref)
835 strbuf_addstr(&buf, ref->peer_ref->name);
836 else
837 strbuf_addstr(&buf, oid_to_hex(&ref->new_oid));
838 }
839 strbuf_addch(&buf, ':');
840 strbuf_addstr(&buf, ref->name);
841 strbuf_addch(&buf, '\n');
842
843 /*
844 * The "--force-with-lease" options without explicit
845 * values to expect have already been expanded into
846 * the ref->old_oid_expect[] field; we can ignore
847 * transport->smart_options->cas altogether and instead
848 * can enumerate them from the refs.
849 */
850 if (ref->expect_old_sha1) {
851 struct strbuf cas = STRBUF_INIT;
852 strbuf_addf(&cas, "%s:%s",
853 ref->name, oid_to_hex(&ref->old_oid_expect));
854 string_list_append(&cas_options, strbuf_detach(&cas, NULL));
855 }
856 }
857 if (buf.len == 0) {
858 string_list_clear(&cas_options, 0);
859 return 0;
860 }
861
862 for_each_string_list_item(cas_option, &cas_options)
863 set_helper_option(transport, "cas", cas_option->string);
864 set_common_push_options(transport, data->name, flags);
865
866 strbuf_addch(&buf, '\n');
867 sendline(data, &buf);
868 strbuf_release(&buf);
869
870 return push_update_refs_status(data, remote_refs, flags);
871}
872
873static int push_refs_with_export(struct transport *transport,
874 struct ref *remote_refs, int flags)
875{
876 struct ref *ref;
877 struct child_process *helper, exporter;
878 struct helper_data *data = transport->data;
879 struct string_list revlist_args = STRING_LIST_INIT_DUP;
880 struct strbuf buf = STRBUF_INIT;
881
882 if (!data->refspecs)
883 die("remote-helper doesn't support push; refspec needed");
884
885 set_common_push_options(transport, data->name, flags);
886 if (flags & TRANSPORT_PUSH_FORCE) {
887 if (set_helper_option(transport, "force", "true") != 0)
888 warning("helper %s does not support 'force'", data->name);
889 }
890
891 helper = get_helper(transport);
892
893 write_constant(helper->in, "export\n");
894
895 for (ref = remote_refs; ref; ref = ref->next) {
896 char *private;
897 struct object_id oid;
898
899 private = apply_refspecs(data->refspecs, data->refspec_nr, ref->name);
900 if (private && !get_sha1(private, oid.hash)) {
901 strbuf_addf(&buf, "^%s", private);
902 string_list_append(&revlist_args, strbuf_detach(&buf, NULL));
903 oidcpy(&ref->old_oid, &oid);
904 }
905 free(private);
906
907 if (ref->peer_ref) {
908 if (strcmp(ref->name, ref->peer_ref->name)) {
909 if (!ref->deletion) {
910 const char *name;
911 int flag;
912
913 /* Follow symbolic refs (mainly for HEAD). */
914 name = resolve_ref_unsafe(
915 ref->peer_ref->name,
916 RESOLVE_REF_READING,
917 oid.hash, &flag);
918 if (!name || !(flag & REF_ISSYMREF))
919 name = ref->peer_ref->name;
920
921 strbuf_addf(&buf, "%s:%s", name, ref->name);
922 } else
923 strbuf_addf(&buf, ":%s", ref->name);
924
925 string_list_append(&revlist_args, "--refspec");
926 string_list_append(&revlist_args, buf.buf);
927 strbuf_release(&buf);
928 }
929 if (!ref->deletion)
930 string_list_append(&revlist_args, ref->peer_ref->name);
931 }
932 }
933
934 if (get_exporter(transport, &exporter, &revlist_args))
935 die("Couldn't run fast-export");
936
937 string_list_clear(&revlist_args, 1);
938
939 if (finish_command(&exporter))
940 die("Error while running fast-export");
941 if (push_update_refs_status(data, remote_refs, flags))
942 return 1;
943
944 if (data->export_marks) {
945 strbuf_addf(&buf, "%s.tmp", data->export_marks);
946 rename(buf.buf, data->export_marks);
947 strbuf_release(&buf);
948 }
949
950 return 0;
951}
952
953static int push_refs(struct transport *transport,
954 struct ref *remote_refs, int flags)
955{
956 struct helper_data *data = transport->data;
957
958 if (process_connect(transport, 1)) {
959 do_take_over(transport);
960 return transport->push_refs(transport, remote_refs, flags);
961 }
962
963 if (!remote_refs) {
964 fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
965 "Perhaps you should specify a branch such as 'master'.\n");
966 return 0;
967 }
968
969 if (data->push)
970 return push_refs_with_push(transport, remote_refs, flags);
971
972 if (data->export)
973 return push_refs_with_export(transport, remote_refs, flags);
974
975 return -1;
976}
977
978
979static int has_attribute(const char *attrs, const char *attr) {
980 int len;
981 if (!attrs)
982 return 0;
983
984 len = strlen(attr);
985 for (;;) {
986 const char *space = strchrnul(attrs, ' ');
987 if (len == space - attrs && !strncmp(attrs, attr, len))
988 return 1;
989 if (!*space)
990 return 0;
991 attrs = space + 1;
992 }
993}
994
995static struct ref *get_refs_list(struct transport *transport, int for_push)
996{
997 struct helper_data *data = transport->data;
998 struct child_process *helper;
999 struct ref *ret = NULL;
1000 struct ref **tail = &ret;
1001 struct ref *posn;
1002 struct strbuf buf = STRBUF_INIT;
1003
1004 helper = get_helper(transport);
1005
1006 if (process_connect(transport, for_push)) {
1007 do_take_over(transport);
1008 return transport->get_refs_list(transport, for_push);
1009 }
1010
1011 if (data->push && for_push)
1012 write_str_in_full(helper->in, "list for-push\n");
1013 else
1014 write_str_in_full(helper->in, "list\n");
1015
1016 while (1) {
1017 char *eov, *eon;
1018 if (recvline(data, &buf))
1019 exit(128);
1020
1021 if (!*buf.buf)
1022 break;
1023
1024 eov = strchr(buf.buf, ' ');
1025 if (!eov)
1026 die("Malformed response in ref list: %s", buf.buf);
1027 eon = strchr(eov + 1, ' ');
1028 *eov = '\0';
1029 if (eon)
1030 *eon = '\0';
1031 *tail = alloc_ref(eov + 1);
1032 if (buf.buf[0] == '@')
1033 (*tail)->symref = xstrdup(buf.buf + 1);
1034 else if (buf.buf[0] != '?')
1035 get_oid_hex(buf.buf, &(*tail)->old_oid);
1036 if (eon) {
1037 if (has_attribute(eon + 1, "unchanged")) {
1038 (*tail)->status |= REF_STATUS_UPTODATE;
1039 if (read_ref((*tail)->name,
1040 (*tail)->old_oid.hash) < 0)
1041 die(N_("Could not read ref %s"),
1042 (*tail)->name);
1043 }
1044 }
1045 tail = &((*tail)->next);
1046 }
1047 if (debug)
1048 fprintf(stderr, "Debug: Read ref listing.\n");
1049 strbuf_release(&buf);
1050
1051 for (posn = ret; posn; posn = posn->next)
1052 resolve_remote_symref(posn, ret);
1053
1054 return ret;
1055}
1056
1057int transport_helper_init(struct transport *transport, const char *name)
1058{
1059 struct helper_data *data = xcalloc(1, sizeof(*data));
1060 data->name = name;
1061
1062 transport_check_allowed(name);
1063
1064 if (getenv("GIT_TRANSPORT_HELPER_DEBUG"))
1065 debug = 1;
1066
1067 transport->data = data;
1068 transport->set_option = set_helper_option;
1069 transport->get_refs_list = get_refs_list;
1070 transport->fetch = fetch;
1071 transport->push_refs = push_refs;
1072 transport->disconnect = release_helper;
1073 transport->connect = connect_helper;
1074 transport->smart_options = &(data->transport_options);
1075 return 0;
1076}
1077
1078/*
1079 * Linux pipes can buffer 65536 bytes at once (and most platforms can
1080 * buffer less), so attempt reads and writes with up to that size.
1081 */
1082#define BUFFERSIZE 65536
1083/* This should be enough to hold debugging message. */
1084#define PBUFFERSIZE 8192
1085
1086/* Print bidirectional transfer loop debug message. */
1087__attribute__((format (printf, 1, 2)))
1088static void transfer_debug(const char *fmt, ...)
1089{
1090 va_list args;
1091 char msgbuf[PBUFFERSIZE];
1092 static int debug_enabled = -1;
1093
1094 if (debug_enabled < 0)
1095 debug_enabled = getenv("GIT_TRANSLOOP_DEBUG") ? 1 : 0;
1096 if (!debug_enabled)
1097 return;
1098
1099 va_start(args, fmt);
1100 vsnprintf(msgbuf, PBUFFERSIZE, fmt, args);
1101 va_end(args);
1102 fprintf(stderr, "Transfer loop debugging: %s\n", msgbuf);
1103}
1104
1105/* Stream state: More data may be coming in this direction. */
1106#define SSTATE_TRANSFERING 0
1107/*
1108 * Stream state: No more data coming in this direction, flushing rest of
1109 * data.
1110 */
1111#define SSTATE_FLUSHING 1
1112/* Stream state: Transfer in this direction finished. */
1113#define SSTATE_FINISHED 2
1114
1115#define STATE_NEEDS_READING(state) ((state) <= SSTATE_TRANSFERING)
1116#define STATE_NEEDS_WRITING(state) ((state) <= SSTATE_FLUSHING)
1117#define STATE_NEEDS_CLOSING(state) ((state) == SSTATE_FLUSHING)
1118
1119/* Unidirectional transfer. */
1120struct unidirectional_transfer {
1121 /* Source */
1122 int src;
1123 /* Destination */
1124 int dest;
1125 /* Is source socket? */
1126 int src_is_sock;
1127 /* Is destination socket? */
1128 int dest_is_sock;
1129 /* Transfer state (TRANSFERRING/FLUSHING/FINISHED) */
1130 int state;
1131 /* Buffer. */
1132 char buf[BUFFERSIZE];
1133 /* Buffer used. */
1134 size_t bufuse;
1135 /* Name of source. */
1136 const char *src_name;
1137 /* Name of destination. */
1138 const char *dest_name;
1139};
1140
1141/* Closes the target (for writing) if transfer has finished. */
1142static void udt_close_if_finished(struct unidirectional_transfer *t)
1143{
1144 if (STATE_NEEDS_CLOSING(t->state) && !t->bufuse) {
1145 t->state = SSTATE_FINISHED;
1146 if (t->dest_is_sock)
1147 shutdown(t->dest, SHUT_WR);
1148 else
1149 close(t->dest);
1150 transfer_debug("Closed %s.", t->dest_name);
1151 }
1152}
1153
1154/*
1155 * Tries to read read data from source into buffer. If buffer is full,
1156 * no data is read. Returns 0 on success, -1 on error.
1157 */
1158static int udt_do_read(struct unidirectional_transfer *t)
1159{
1160 ssize_t bytes;
1161
1162 if (t->bufuse == BUFFERSIZE)
1163 return 0; /* No space for more. */
1164
1165 transfer_debug("%s is readable", t->src_name);
1166 bytes = read(t->src, t->buf + t->bufuse, BUFFERSIZE - t->bufuse);
1167 if (bytes < 0 && errno != EWOULDBLOCK && errno != EAGAIN &&
1168 errno != EINTR) {
1169 error_errno("read(%s) failed", t->src_name);
1170 return -1;
1171 } else if (bytes == 0) {
1172 transfer_debug("%s EOF (with %i bytes in buffer)",
1173 t->src_name, (int)t->bufuse);
1174 t->state = SSTATE_FLUSHING;
1175 } else if (bytes > 0) {
1176 t->bufuse += bytes;
1177 transfer_debug("Read %i bytes from %s (buffer now at %i)",
1178 (int)bytes, t->src_name, (int)t->bufuse);
1179 }
1180 return 0;
1181}
1182
1183/* Tries to write data from buffer into destination. If buffer is empty,
1184 * no data is written. Returns 0 on success, -1 on error.
1185 */
1186static int udt_do_write(struct unidirectional_transfer *t)
1187{
1188 ssize_t bytes;
1189
1190 if (t->bufuse == 0)
1191 return 0; /* Nothing to write. */
1192
1193 transfer_debug("%s is writable", t->dest_name);
1194 bytes = xwrite(t->dest, t->buf, t->bufuse);
1195 if (bytes < 0 && errno != EWOULDBLOCK) {
1196 error_errno("write(%s) failed", t->dest_name);
1197 return -1;
1198 } else if (bytes > 0) {
1199 t->bufuse -= bytes;
1200 if (t->bufuse)
1201 memmove(t->buf, t->buf + bytes, t->bufuse);
1202 transfer_debug("Wrote %i bytes to %s (buffer now at %i)",
1203 (int)bytes, t->dest_name, (int)t->bufuse);
1204 }
1205 return 0;
1206}
1207
1208
1209/* State of bidirectional transfer loop. */
1210struct bidirectional_transfer_state {
1211 /* Direction from program to git. */
1212 struct unidirectional_transfer ptg;
1213 /* Direction from git to program. */
1214 struct unidirectional_transfer gtp;
1215};
1216
1217static void *udt_copy_task_routine(void *udt)
1218{
1219 struct unidirectional_transfer *t = (struct unidirectional_transfer *)udt;
1220 while (t->state != SSTATE_FINISHED) {
1221 if (STATE_NEEDS_READING(t->state))
1222 if (udt_do_read(t))
1223 return NULL;
1224 if (STATE_NEEDS_WRITING(t->state))
1225 if (udt_do_write(t))
1226 return NULL;
1227 if (STATE_NEEDS_CLOSING(t->state))
1228 udt_close_if_finished(t);
1229 }
1230 return udt; /* Just some non-NULL value. */
1231}
1232
1233#ifndef NO_PTHREADS
1234
1235/*
1236 * Join thread, with appropriate errors on failure. Name is name for the
1237 * thread (for error messages). Returns 0 on success, 1 on failure.
1238 */
1239static int tloop_join(pthread_t thread, const char *name)
1240{
1241 int err;
1242 void *tret;
1243 err = pthread_join(thread, &tret);
1244 if (!tret) {
1245 error("%s thread failed", name);
1246 return 1;
1247 }
1248 if (err) {
1249 error("%s thread failed to join: %s", name, strerror(err));
1250 return 1;
1251 }
1252 return 0;
1253}
1254
1255/*
1256 * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1257 * -1 on failure.
1258 */
1259static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1260{
1261 pthread_t gtp_thread;
1262 pthread_t ptg_thread;
1263 int err;
1264 int ret = 0;
1265 err = pthread_create(>p_thread, NULL, udt_copy_task_routine,
1266 &s->gtp);
1267 if (err)
1268 die("Can't start thread for copying data: %s", strerror(err));
1269 err = pthread_create(&ptg_thread, NULL, udt_copy_task_routine,
1270 &s->ptg);
1271 if (err)
1272 die("Can't start thread for copying data: %s", strerror(err));
1273
1274 ret |= tloop_join(gtp_thread, "Git to program copy");
1275 ret |= tloop_join(ptg_thread, "Program to git copy");
1276 return ret;
1277}
1278#else
1279
1280/* Close the source and target (for writing) for transfer. */
1281static void udt_kill_transfer(struct unidirectional_transfer *t)
1282{
1283 t->state = SSTATE_FINISHED;
1284 /*
1285 * Socket read end left open isn't a disaster if nobody
1286 * attempts to read from it (mingw compat headers do not
1287 * have SHUT_RD)...
1288 *
1289 * We can't fully close the socket since otherwise gtp
1290 * task would first close the socket it sends data to
1291 * while closing the ptg file descriptors.
1292 */
1293 if (!t->src_is_sock)
1294 close(t->src);
1295 if (t->dest_is_sock)
1296 shutdown(t->dest, SHUT_WR);
1297 else
1298 close(t->dest);
1299}
1300
1301/*
1302 * Join process, with appropriate errors on failure. Name is name for the
1303 * process (for error messages). Returns 0 on success, 1 on failure.
1304 */
1305static int tloop_join(pid_t pid, const char *name)
1306{
1307 int tret;
1308 if (waitpid(pid, &tret, 0) < 0) {
1309 error_errno("%s process failed to wait", name);
1310 return 1;
1311 }
1312 if (!WIFEXITED(tret) || WEXITSTATUS(tret)) {
1313 error("%s process failed", name);
1314 return 1;
1315 }
1316 return 0;
1317}
1318
1319/*
1320 * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1321 * -1 on failure.
1322 */
1323static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1324{
1325 pid_t pid1, pid2;
1326 int ret = 0;
1327
1328 /* Fork thread #1: git to program. */
1329 pid1 = fork();
1330 if (pid1 < 0)
1331 die_errno("Can't start thread for copying data");
1332 else if (pid1 == 0) {
1333 udt_kill_transfer(&s->ptg);
1334 exit(udt_copy_task_routine(&s->gtp) ? 0 : 1);
1335 }
1336
1337 /* Fork thread #2: program to git. */
1338 pid2 = fork();
1339 if (pid2 < 0)
1340 die_errno("Can't start thread for copying data");
1341 else if (pid2 == 0) {
1342 udt_kill_transfer(&s->gtp);
1343 exit(udt_copy_task_routine(&s->ptg) ? 0 : 1);
1344 }
1345
1346 /*
1347 * Close both streams in parent as to not interfere with
1348 * end of file detection and wait for both tasks to finish.
1349 */
1350 udt_kill_transfer(&s->gtp);
1351 udt_kill_transfer(&s->ptg);
1352 ret |= tloop_join(pid1, "Git to program copy");
1353 ret |= tloop_join(pid2, "Program to git copy");
1354 return ret;
1355}
1356#endif
1357
1358/*
1359 * Copies data from stdin to output and from input to stdout simultaneously.
1360 * Additionally filtering through given filter. If filter is NULL, uses
1361 * identity filter.
1362 */
1363int bidirectional_transfer_loop(int input, int output)
1364{
1365 struct bidirectional_transfer_state state;
1366
1367 /* Fill the state fields. */
1368 state.ptg.src = input;
1369 state.ptg.dest = 1;
1370 state.ptg.src_is_sock = (input == output);
1371 state.ptg.dest_is_sock = 0;
1372 state.ptg.state = SSTATE_TRANSFERING;
1373 state.ptg.bufuse = 0;
1374 state.ptg.src_name = "remote input";
1375 state.ptg.dest_name = "stdout";
1376
1377 state.gtp.src = 0;
1378 state.gtp.dest = output;
1379 state.gtp.src_is_sock = 0;
1380 state.gtp.dest_is_sock = (input == output);
1381 state.gtp.state = SSTATE_TRANSFERING;
1382 state.gtp.bufuse = 0;
1383 state.gtp.src_name = "stdin";
1384 state.gtp.dest_name = "remote output";
1385
1386 return tloop_spawnwait_tasks(&state);
1387}