1#include "cache.h"
2#include "transport.h"
3#include "quote.h"
4#include "run-command.h"
5#include "commit.h"
6#include "diff.h"
7#include "revision.h"
8#include "remote.h"
9#include "string-list.h"
10#include "thread-utils.h"
11#include "sigchain.h"
12#include "argv-array.h"
13#include "refs.h"
14#include "transport-internal.h"
15#include "protocol.h"
16
17static int debug;
18
19struct helper_data {
20 const char *name;
21 struct child_process *helper;
22 FILE *out;
23 unsigned fetch : 1,
24 import : 1,
25 bidi_import : 1,
26 export : 1,
27 option : 1,
28 push : 1,
29 connect : 1,
30 stateless_connect : 1,
31 signed_tags : 1,
32 check_connectivity : 1,
33 no_disconnect_req : 1,
34 no_private_update : 1;
35 char *export_marks;
36 char *import_marks;
37 /* These go from remote name (as in "list") to private name */
38 struct refspec *refspecs;
39 int refspec_nr;
40 /* Transport options for fetch-pack/send-pack (should one of
41 * those be invoked).
42 */
43 struct git_transport_options transport_options;
44};
45
46static void sendline(struct helper_data *helper, struct strbuf *buffer)
47{
48 if (debug)
49 fprintf(stderr, "Debug: Remote helper: -> %s", buffer->buf);
50 if (write_in_full(helper->helper->in, buffer->buf, buffer->len) < 0)
51 die_errno("Full write to remote helper failed");
52}
53
54static int recvline_fh(FILE *helper, struct strbuf *buffer)
55{
56 strbuf_reset(buffer);
57 if (debug)
58 fprintf(stderr, "Debug: Remote helper: Waiting...\n");
59 if (strbuf_getline(buffer, helper) == EOF) {
60 if (debug)
61 fprintf(stderr, "Debug: Remote helper quit.\n");
62 return 1;
63 }
64
65 if (debug)
66 fprintf(stderr, "Debug: Remote helper: <- %s\n", buffer->buf);
67 return 0;
68}
69
70static int recvline(struct helper_data *helper, struct strbuf *buffer)
71{
72 return recvline_fh(helper->out, buffer);
73}
74
75static void write_constant(int fd, const char *str)
76{
77 if (debug)
78 fprintf(stderr, "Debug: Remote helper: -> %s", str);
79 if (write_in_full(fd, str, strlen(str)) < 0)
80 die_errno("Full write to remote helper failed");
81}
82
83static const char *remove_ext_force(const char *url)
84{
85 if (url) {
86 const char *colon = strchr(url, ':');
87 if (colon && colon[1] == ':')
88 return colon + 2;
89 }
90 return url;
91}
92
93static void do_take_over(struct transport *transport)
94{
95 struct helper_data *data;
96 data = (struct helper_data *)transport->data;
97 transport_take_over(transport, data->helper);
98 fclose(data->out);
99 free(data);
100}
101
102static void standard_options(struct transport *t);
103
104static struct child_process *get_helper(struct transport *transport)
105{
106 struct helper_data *data = transport->data;
107 struct strbuf buf = STRBUF_INIT;
108 struct child_process *helper;
109 const char **refspecs = NULL;
110 int refspec_nr = 0;
111 int refspec_alloc = 0;
112 int duped;
113 int code;
114
115 if (data->helper)
116 return data->helper;
117
118 helper = xmalloc(sizeof(*helper));
119 child_process_init(helper);
120 helper->in = -1;
121 helper->out = -1;
122 helper->err = 0;
123 argv_array_pushf(&helper->args, "git-remote-%s", data->name);
124 argv_array_push(&helper->args, transport->remote->name);
125 argv_array_push(&helper->args, remove_ext_force(transport->url));
126 helper->git_cmd = 0;
127 helper->silent_exec_failure = 1;
128
129 if (have_git_dir())
130 argv_array_pushf(&helper->env_array, "%s=%s",
131 GIT_DIR_ENVIRONMENT, get_git_dir());
132
133 code = start_command(helper);
134 if (code < 0 && errno == ENOENT)
135 die("Unable to find remote helper for '%s'", data->name);
136 else if (code != 0)
137 exit(code);
138
139 data->helper = helper;
140 data->no_disconnect_req = 0;
141
142 /*
143 * Open the output as FILE* so strbuf_getline_*() family of
144 * functions can be used.
145 * Do this with duped fd because fclose() will close the fd,
146 * and stuff like taking over will require the fd to remain.
147 */
148 duped = dup(helper->out);
149 if (duped < 0)
150 die_errno("Can't dup helper output fd");
151 data->out = xfdopen(duped, "r");
152
153 write_constant(helper->in, "capabilities\n");
154
155 while (1) {
156 const char *capname, *arg;
157 int mandatory = 0;
158 if (recvline(data, &buf))
159 exit(128);
160
161 if (!*buf.buf)
162 break;
163
164 if (*buf.buf == '*') {
165 capname = buf.buf + 1;
166 mandatory = 1;
167 } else
168 capname = buf.buf;
169
170 if (debug)
171 fprintf(stderr, "Debug: Got cap %s\n", capname);
172 if (!strcmp(capname, "fetch"))
173 data->fetch = 1;
174 else if (!strcmp(capname, "option"))
175 data->option = 1;
176 else if (!strcmp(capname, "push"))
177 data->push = 1;
178 else if (!strcmp(capname, "import"))
179 data->import = 1;
180 else if (!strcmp(capname, "bidi-import"))
181 data->bidi_import = 1;
182 else if (!strcmp(capname, "export"))
183 data->export = 1;
184 else if (!strcmp(capname, "check-connectivity"))
185 data->check_connectivity = 1;
186 else if (!data->refspecs && skip_prefix(capname, "refspec ", &arg)) {
187 ALLOC_GROW(refspecs,
188 refspec_nr + 1,
189 refspec_alloc);
190 refspecs[refspec_nr++] = xstrdup(arg);
191 } else if (!strcmp(capname, "connect")) {
192 data->connect = 1;
193 } else if (!strcmp(capname, "stateless-connect")) {
194 data->stateless_connect = 1;
195 } else if (!strcmp(capname, "signed-tags")) {
196 data->signed_tags = 1;
197 } else if (skip_prefix(capname, "export-marks ", &arg)) {
198 data->export_marks = xstrdup(arg);
199 } else if (skip_prefix(capname, "import-marks ", &arg)) {
200 data->import_marks = xstrdup(arg);
201 } else if (starts_with(capname, "no-private-update")) {
202 data->no_private_update = 1;
203 } else if (mandatory) {
204 die("Unknown mandatory capability %s. This remote "
205 "helper probably needs newer version of Git.",
206 capname);
207 }
208 }
209 if (refspecs) {
210 int i;
211 data->refspec_nr = refspec_nr;
212 data->refspecs = parse_fetch_refspec(refspec_nr, refspecs);
213 for (i = 0; i < refspec_nr; i++)
214 free((char *)refspecs[i]);
215 free(refspecs);
216 } else if (data->import || data->bidi_import || data->export) {
217 warning("This remote helper should implement refspec capability.");
218 }
219 strbuf_release(&buf);
220 if (debug)
221 fprintf(stderr, "Debug: Capabilities complete.\n");
222 standard_options(transport);
223 return data->helper;
224}
225
226static int disconnect_helper(struct transport *transport)
227{
228 struct helper_data *data = transport->data;
229 int res = 0;
230
231 if (data->helper) {
232 if (debug)
233 fprintf(stderr, "Debug: Disconnecting.\n");
234 if (!data->no_disconnect_req) {
235 /*
236 * Ignore write errors; there's nothing we can do,
237 * since we're about to close the pipe anyway. And the
238 * most likely error is EPIPE due to the helper dying
239 * to report an error itself.
240 */
241 sigchain_push(SIGPIPE, SIG_IGN);
242 xwrite(data->helper->in, "\n", 1);
243 sigchain_pop(SIGPIPE);
244 }
245 close(data->helper->in);
246 close(data->helper->out);
247 fclose(data->out);
248 res = finish_command(data->helper);
249 FREE_AND_NULL(data->helper);
250 }
251 return res;
252}
253
254static const char *unsupported_options[] = {
255 TRANS_OPT_UPLOADPACK,
256 TRANS_OPT_RECEIVEPACK,
257 TRANS_OPT_THIN,
258 TRANS_OPT_KEEP
259 };
260
261static const char *boolean_options[] = {
262 TRANS_OPT_THIN,
263 TRANS_OPT_KEEP,
264 TRANS_OPT_FOLLOWTAGS,
265 TRANS_OPT_DEEPEN_RELATIVE
266 };
267
268static int strbuf_set_helper_option(struct helper_data *data,
269 struct strbuf *buf)
270{
271 int ret;
272
273 sendline(data, buf);
274 if (recvline(data, buf))
275 exit(128);
276
277 if (!strcmp(buf->buf, "ok"))
278 ret = 0;
279 else if (starts_with(buf->buf, "error"))
280 ret = -1;
281 else if (!strcmp(buf->buf, "unsupported"))
282 ret = 1;
283 else {
284 warning("%s unexpectedly said: '%s'", data->name, buf->buf);
285 ret = 1;
286 }
287 return ret;
288}
289
290static int string_list_set_helper_option(struct helper_data *data,
291 const char *name,
292 struct string_list *list)
293{
294 struct strbuf buf = STRBUF_INIT;
295 int i, ret = 0;
296
297 for (i = 0; i < list->nr; i++) {
298 strbuf_addf(&buf, "option %s ", name);
299 quote_c_style(list->items[i].string, &buf, NULL, 0);
300 strbuf_addch(&buf, '\n');
301
302 if ((ret = strbuf_set_helper_option(data, &buf)))
303 break;
304 strbuf_reset(&buf);
305 }
306 strbuf_release(&buf);
307 return ret;
308}
309
310static int set_helper_option(struct transport *transport,
311 const char *name, const char *value)
312{
313 struct helper_data *data = transport->data;
314 struct strbuf buf = STRBUF_INIT;
315 int i, ret, is_bool = 0;
316
317 get_helper(transport);
318
319 if (!data->option)
320 return 1;
321
322 if (!strcmp(name, "deepen-not"))
323 return string_list_set_helper_option(data, name,
324 (struct string_list *)value);
325
326 for (i = 0; i < ARRAY_SIZE(unsupported_options); i++) {
327 if (!strcmp(name, unsupported_options[i]))
328 return 1;
329 }
330
331 for (i = 0; i < ARRAY_SIZE(boolean_options); i++) {
332 if (!strcmp(name, boolean_options[i])) {
333 is_bool = 1;
334 break;
335 }
336 }
337
338 strbuf_addf(&buf, "option %s ", name);
339 if (is_bool)
340 strbuf_addstr(&buf, value ? "true" : "false");
341 else
342 quote_c_style(value, &buf, NULL, 0);
343 strbuf_addch(&buf, '\n');
344
345 ret = strbuf_set_helper_option(data, &buf);
346 strbuf_release(&buf);
347 return ret;
348}
349
350static void standard_options(struct transport *t)
351{
352 char buf[16];
353 int v = t->verbose;
354
355 set_helper_option(t, "progress", t->progress ? "true" : "false");
356
357 xsnprintf(buf, sizeof(buf), "%d", v + 1);
358 set_helper_option(t, "verbosity", buf);
359
360 switch (t->family) {
361 case TRANSPORT_FAMILY_ALL:
362 /*
363 * this is already the default,
364 * do not break old remote helpers by setting "all" here
365 */
366 break;
367 case TRANSPORT_FAMILY_IPV4:
368 set_helper_option(t, "family", "ipv4");
369 break;
370 case TRANSPORT_FAMILY_IPV6:
371 set_helper_option(t, "family", "ipv6");
372 break;
373 }
374}
375
376static int release_helper(struct transport *transport)
377{
378 int res = 0;
379 struct helper_data *data = transport->data;
380 free_refspec(data->refspec_nr, data->refspecs);
381 data->refspecs = NULL;
382 res = disconnect_helper(transport);
383 free(transport->data);
384 return res;
385}
386
387static int fetch_with_fetch(struct transport *transport,
388 int nr_heads, struct ref **to_fetch)
389{
390 struct helper_data *data = transport->data;
391 int i;
392 struct strbuf buf = STRBUF_INIT;
393
394 for (i = 0; i < nr_heads; i++) {
395 const struct ref *posn = to_fetch[i];
396 if (posn->status & REF_STATUS_UPTODATE)
397 continue;
398
399 strbuf_addf(&buf, "fetch %s %s\n",
400 oid_to_hex(&posn->old_oid),
401 posn->symref ? posn->symref : posn->name);
402 }
403
404 strbuf_addch(&buf, '\n');
405 sendline(data, &buf);
406
407 while (1) {
408 if (recvline(data, &buf))
409 exit(128);
410
411 if (starts_with(buf.buf, "lock ")) {
412 const char *name = buf.buf + 5;
413 if (transport->pack_lockfile)
414 warning("%s also locked %s", data->name, name);
415 else
416 transport->pack_lockfile = xstrdup(name);
417 }
418 else if (data->check_connectivity &&
419 data->transport_options.check_self_contained_and_connected &&
420 !strcmp(buf.buf, "connectivity-ok"))
421 data->transport_options.self_contained_and_connected = 1;
422 else if (!buf.len)
423 break;
424 else
425 warning("%s unexpectedly said: '%s'", data->name, buf.buf);
426 }
427 strbuf_release(&buf);
428 return 0;
429}
430
431static int get_importer(struct transport *transport, struct child_process *fastimport)
432{
433 struct child_process *helper = get_helper(transport);
434 struct helper_data *data = transport->data;
435 int cat_blob_fd, code;
436 child_process_init(fastimport);
437 fastimport->in = helper->out;
438 argv_array_push(&fastimport->args, "fast-import");
439 argv_array_push(&fastimport->args, debug ? "--stats" : "--quiet");
440
441 if (data->bidi_import) {
442 cat_blob_fd = xdup(helper->in);
443 argv_array_pushf(&fastimport->args, "--cat-blob-fd=%d", cat_blob_fd);
444 }
445 fastimport->git_cmd = 1;
446
447 code = start_command(fastimport);
448 return code;
449}
450
451static int get_exporter(struct transport *transport,
452 struct child_process *fastexport,
453 struct string_list *revlist_args)
454{
455 struct helper_data *data = transport->data;
456 struct child_process *helper = get_helper(transport);
457 int i;
458
459 child_process_init(fastexport);
460
461 /* we need to duplicate helper->in because we want to use it after
462 * fastexport is done with it. */
463 fastexport->out = dup(helper->in);
464 argv_array_push(&fastexport->args, "fast-export");
465 argv_array_push(&fastexport->args, "--use-done-feature");
466 argv_array_push(&fastexport->args, data->signed_tags ?
467 "--signed-tags=verbatim" : "--signed-tags=warn-strip");
468 if (data->export_marks)
469 argv_array_pushf(&fastexport->args, "--export-marks=%s.tmp", data->export_marks);
470 if (data->import_marks)
471 argv_array_pushf(&fastexport->args, "--import-marks=%s", data->import_marks);
472
473 for (i = 0; i < revlist_args->nr; i++)
474 argv_array_push(&fastexport->args, revlist_args->items[i].string);
475
476 fastexport->git_cmd = 1;
477 return start_command(fastexport);
478}
479
480static int fetch_with_import(struct transport *transport,
481 int nr_heads, struct ref **to_fetch)
482{
483 struct child_process fastimport;
484 struct helper_data *data = transport->data;
485 int i;
486 struct ref *posn;
487 struct strbuf buf = STRBUF_INIT;
488
489 get_helper(transport);
490
491 if (get_importer(transport, &fastimport))
492 die("Couldn't run fast-import");
493
494 for (i = 0; i < nr_heads; i++) {
495 posn = to_fetch[i];
496 if (posn->status & REF_STATUS_UPTODATE)
497 continue;
498
499 strbuf_addf(&buf, "import %s\n",
500 posn->symref ? posn->symref : posn->name);
501 sendline(data, &buf);
502 strbuf_reset(&buf);
503 }
504
505 write_constant(data->helper->in, "\n");
506 /*
507 * remote-helpers that advertise the bidi-import capability are required to
508 * buffer the complete batch of import commands until this newline before
509 * sending data to fast-import.
510 * These helpers read back data from fast-import on their stdin, which could
511 * be mixed with import commands, otherwise.
512 */
513
514 if (finish_command(&fastimport))
515 die("Error while running fast-import");
516
517 /*
518 * The fast-import stream of a remote helper that advertises
519 * the "refspec" capability writes to the refs named after the
520 * right hand side of the first refspec matching each ref we
521 * were fetching.
522 *
523 * (If no "refspec" capability was specified, for historical
524 * reasons we default to the equivalent of *:*.)
525 *
526 * Store the result in to_fetch[i].old_sha1. Callers such
527 * as "git fetch" can use the value to write feedback to the
528 * terminal, populate FETCH_HEAD, and determine what new value
529 * should be written to peer_ref if the update is a
530 * fast-forward or this is a forced update.
531 */
532 for (i = 0; i < nr_heads; i++) {
533 char *private, *name;
534 posn = to_fetch[i];
535 if (posn->status & REF_STATUS_UPTODATE)
536 continue;
537 name = posn->symref ? posn->symref : posn->name;
538 if (data->refspecs)
539 private = apply_refspecs(data->refspecs, data->refspec_nr, name);
540 else
541 private = xstrdup(name);
542 if (private) {
543 if (read_ref(private, &posn->old_oid) < 0)
544 die("Could not read ref %s", private);
545 free(private);
546 }
547 }
548 strbuf_release(&buf);
549 return 0;
550}
551
552static int run_connect(struct transport *transport, struct strbuf *cmdbuf)
553{
554 struct helper_data *data = transport->data;
555 int ret = 0;
556 int duped;
557 FILE *input;
558 struct child_process *helper;
559
560 helper = get_helper(transport);
561
562 /*
563 * Yes, dup the pipe another time, as we need unbuffered version
564 * of input pipe as FILE*. fclose() closes the underlying fd and
565 * stream buffering only can be changed before first I/O operation
566 * on it.
567 */
568 duped = dup(helper->out);
569 if (duped < 0)
570 die_errno("Can't dup helper output fd");
571 input = xfdopen(duped, "r");
572 setvbuf(input, NULL, _IONBF, 0);
573
574 sendline(data, cmdbuf);
575 if (recvline_fh(input, cmdbuf))
576 exit(128);
577
578 if (!strcmp(cmdbuf->buf, "")) {
579 data->no_disconnect_req = 1;
580 if (debug)
581 fprintf(stderr, "Debug: Smart transport connection "
582 "ready.\n");
583 ret = 1;
584 } else if (!strcmp(cmdbuf->buf, "fallback")) {
585 if (debug)
586 fprintf(stderr, "Debug: Falling back to dumb "
587 "transport.\n");
588 } else {
589 die("Unknown response to connect: %s",
590 cmdbuf->buf);
591 }
592
593 fclose(input);
594 return ret;
595}
596
597static int process_connect_service(struct transport *transport,
598 const char *name, const char *exec)
599{
600 struct helper_data *data = transport->data;
601 struct strbuf cmdbuf = STRBUF_INIT;
602 int ret = 0;
603
604 /*
605 * Handle --upload-pack and friends. This is fire and forget...
606 * just warn if it fails.
607 */
608 if (strcmp(name, exec)) {
609 int r = set_helper_option(transport, "servpath", exec);
610 if (r > 0)
611 warning("Setting remote service path not supported by protocol.");
612 else if (r < 0)
613 warning("Invalid remote service path.");
614 }
615
616 if (data->connect) {
617 strbuf_addf(&cmdbuf, "connect %s\n", name);
618 ret = run_connect(transport, &cmdbuf);
619 } else if (data->stateless_connect &&
620 (get_protocol_version_config() == protocol_v2) &&
621 !strcmp("git-upload-pack", name)) {
622 strbuf_addf(&cmdbuf, "stateless-connect %s\n", name);
623 ret = run_connect(transport, &cmdbuf);
624 if (ret)
625 transport->stateless_rpc = 1;
626 }
627
628 strbuf_release(&cmdbuf);
629 return ret;
630}
631
632static int process_connect(struct transport *transport,
633 int for_push)
634{
635 struct helper_data *data = transport->data;
636 const char *name;
637 const char *exec;
638
639 name = for_push ? "git-receive-pack" : "git-upload-pack";
640 if (for_push)
641 exec = data->transport_options.receivepack;
642 else
643 exec = data->transport_options.uploadpack;
644
645 return process_connect_service(transport, name, exec);
646}
647
648static int connect_helper(struct transport *transport, const char *name,
649 const char *exec, int fd[2])
650{
651 struct helper_data *data = transport->data;
652
653 /* Get_helper so connect is inited. */
654 get_helper(transport);
655 if (!data->connect)
656 die("Operation not supported by protocol.");
657
658 if (!process_connect_service(transport, name, exec))
659 die("Can't connect to subservice %s.", name);
660
661 fd[0] = data->helper->out;
662 fd[1] = data->helper->in;
663 return 0;
664}
665
666static int fetch(struct transport *transport,
667 int nr_heads, struct ref **to_fetch)
668{
669 struct helper_data *data = transport->data;
670 int i, count;
671
672 if (process_connect(transport, 0)) {
673 do_take_over(transport);
674 return transport->vtable->fetch(transport, nr_heads, to_fetch);
675 }
676
677 count = 0;
678 for (i = 0; i < nr_heads; i++)
679 if (!(to_fetch[i]->status & REF_STATUS_UPTODATE))
680 count++;
681
682 if (!count)
683 return 0;
684
685 if (data->check_connectivity &&
686 data->transport_options.check_self_contained_and_connected)
687 set_helper_option(transport, "check-connectivity", "true");
688
689 if (transport->cloning)
690 set_helper_option(transport, "cloning", "true");
691
692 if (data->transport_options.update_shallow)
693 set_helper_option(transport, "update-shallow", "true");
694
695 if (data->fetch)
696 return fetch_with_fetch(transport, nr_heads, to_fetch);
697
698 if (data->import)
699 return fetch_with_import(transport, nr_heads, to_fetch);
700
701 return -1;
702}
703
704static int push_update_ref_status(struct strbuf *buf,
705 struct ref **ref,
706 struct ref *remote_refs)
707{
708 char *refname, *msg;
709 int status, forced = 0;
710
711 if (starts_with(buf->buf, "ok ")) {
712 status = REF_STATUS_OK;
713 refname = buf->buf + 3;
714 } else if (starts_with(buf->buf, "error ")) {
715 status = REF_STATUS_REMOTE_REJECT;
716 refname = buf->buf + 6;
717 } else
718 die("expected ok/error, helper said '%s'", buf->buf);
719
720 msg = strchr(refname, ' ');
721 if (msg) {
722 struct strbuf msg_buf = STRBUF_INIT;
723 const char *end;
724
725 *msg++ = '\0';
726 if (!unquote_c_style(&msg_buf, msg, &end))
727 msg = strbuf_detach(&msg_buf, NULL);
728 else
729 msg = xstrdup(msg);
730 strbuf_release(&msg_buf);
731
732 if (!strcmp(msg, "no match")) {
733 status = REF_STATUS_NONE;
734 FREE_AND_NULL(msg);
735 }
736 else if (!strcmp(msg, "up to date")) {
737 status = REF_STATUS_UPTODATE;
738 FREE_AND_NULL(msg);
739 }
740 else if (!strcmp(msg, "non-fast forward")) {
741 status = REF_STATUS_REJECT_NONFASTFORWARD;
742 FREE_AND_NULL(msg);
743 }
744 else if (!strcmp(msg, "already exists")) {
745 status = REF_STATUS_REJECT_ALREADY_EXISTS;
746 FREE_AND_NULL(msg);
747 }
748 else if (!strcmp(msg, "fetch first")) {
749 status = REF_STATUS_REJECT_FETCH_FIRST;
750 FREE_AND_NULL(msg);
751 }
752 else if (!strcmp(msg, "needs force")) {
753 status = REF_STATUS_REJECT_NEEDS_FORCE;
754 FREE_AND_NULL(msg);
755 }
756 else if (!strcmp(msg, "stale info")) {
757 status = REF_STATUS_REJECT_STALE;
758 FREE_AND_NULL(msg);
759 }
760 else if (!strcmp(msg, "forced update")) {
761 forced = 1;
762 FREE_AND_NULL(msg);
763 }
764 }
765
766 if (*ref)
767 *ref = find_ref_by_name(*ref, refname);
768 if (!*ref)
769 *ref = find_ref_by_name(remote_refs, refname);
770 if (!*ref) {
771 warning("helper reported unexpected status of %s", refname);
772 return 1;
773 }
774
775 if ((*ref)->status != REF_STATUS_NONE) {
776 /*
777 * Earlier, the ref was marked not to be pushed, so ignore the ref
778 * status reported by the remote helper if the latter is 'no match'.
779 */
780 if (status == REF_STATUS_NONE)
781 return 1;
782 }
783
784 (*ref)->status = status;
785 (*ref)->forced_update |= forced;
786 (*ref)->remote_status = msg;
787 return !(status == REF_STATUS_OK);
788}
789
790static int push_update_refs_status(struct helper_data *data,
791 struct ref *remote_refs,
792 int flags)
793{
794 struct strbuf buf = STRBUF_INIT;
795 struct ref *ref = remote_refs;
796 int ret = 0;
797
798 for (;;) {
799 char *private;
800
801 if (recvline(data, &buf)) {
802 ret = 1;
803 break;
804 }
805
806 if (!buf.len)
807 break;
808
809 if (push_update_ref_status(&buf, &ref, remote_refs))
810 continue;
811
812 if (flags & TRANSPORT_PUSH_DRY_RUN || !data->refspecs || data->no_private_update)
813 continue;
814
815 /* propagate back the update to the remote namespace */
816 private = apply_refspecs(data->refspecs, data->refspec_nr, ref->name);
817 if (!private)
818 continue;
819 update_ref("update by helper", private, &ref->new_oid, NULL,
820 0, 0);
821 free(private);
822 }
823 strbuf_release(&buf);
824 return ret;
825}
826
827static void set_common_push_options(struct transport *transport,
828 const char *name, int flags)
829{
830 if (flags & TRANSPORT_PUSH_DRY_RUN) {
831 if (set_helper_option(transport, "dry-run", "true") != 0)
832 die("helper %s does not support dry-run", name);
833 } else if (flags & TRANSPORT_PUSH_CERT_ALWAYS) {
834 if (set_helper_option(transport, TRANS_OPT_PUSH_CERT, "true") != 0)
835 die("helper %s does not support --signed", name);
836 } else if (flags & TRANSPORT_PUSH_CERT_IF_ASKED) {
837 if (set_helper_option(transport, TRANS_OPT_PUSH_CERT, "if-asked") != 0)
838 die("helper %s does not support --signed=if-asked", name);
839 }
840
841 if (flags & TRANSPORT_PUSH_OPTIONS) {
842 struct string_list_item *item;
843 for_each_string_list_item(item, transport->push_options)
844 if (set_helper_option(transport, "push-option", item->string) != 0)
845 die("helper %s does not support 'push-option'", name);
846 }
847}
848
849static int push_refs_with_push(struct transport *transport,
850 struct ref *remote_refs, int flags)
851{
852 int force_all = flags & TRANSPORT_PUSH_FORCE;
853 int mirror = flags & TRANSPORT_PUSH_MIRROR;
854 struct helper_data *data = transport->data;
855 struct strbuf buf = STRBUF_INIT;
856 struct ref *ref;
857 struct string_list cas_options = STRING_LIST_INIT_DUP;
858 struct string_list_item *cas_option;
859
860 get_helper(transport);
861 if (!data->push)
862 return 1;
863
864 for (ref = remote_refs; ref; ref = ref->next) {
865 if (!ref->peer_ref && !mirror)
866 continue;
867
868 /* Check for statuses set by set_ref_status_for_push() */
869 switch (ref->status) {
870 case REF_STATUS_REJECT_NONFASTFORWARD:
871 case REF_STATUS_REJECT_STALE:
872 case REF_STATUS_REJECT_ALREADY_EXISTS:
873 case REF_STATUS_UPTODATE:
874 continue;
875 default:
876 ; /* do nothing */
877 }
878
879 if (force_all)
880 ref->force = 1;
881
882 strbuf_addstr(&buf, "push ");
883 if (!ref->deletion) {
884 if (ref->force)
885 strbuf_addch(&buf, '+');
886 if (ref->peer_ref)
887 strbuf_addstr(&buf, ref->peer_ref->name);
888 else
889 strbuf_addstr(&buf, oid_to_hex(&ref->new_oid));
890 }
891 strbuf_addch(&buf, ':');
892 strbuf_addstr(&buf, ref->name);
893 strbuf_addch(&buf, '\n');
894
895 /*
896 * The "--force-with-lease" options without explicit
897 * values to expect have already been expanded into
898 * the ref->old_oid_expect[] field; we can ignore
899 * transport->smart_options->cas altogether and instead
900 * can enumerate them from the refs.
901 */
902 if (ref->expect_old_sha1) {
903 struct strbuf cas = STRBUF_INIT;
904 strbuf_addf(&cas, "%s:%s",
905 ref->name, oid_to_hex(&ref->old_oid_expect));
906 string_list_append_nodup(&cas_options,
907 strbuf_detach(&cas, NULL));
908 }
909 }
910 if (buf.len == 0) {
911 string_list_clear(&cas_options, 0);
912 return 0;
913 }
914
915 for_each_string_list_item(cas_option, &cas_options)
916 set_helper_option(transport, "cas", cas_option->string);
917 set_common_push_options(transport, data->name, flags);
918
919 strbuf_addch(&buf, '\n');
920 sendline(data, &buf);
921 strbuf_release(&buf);
922 string_list_clear(&cas_options, 0);
923
924 return push_update_refs_status(data, remote_refs, flags);
925}
926
927static int push_refs_with_export(struct transport *transport,
928 struct ref *remote_refs, int flags)
929{
930 struct ref *ref;
931 struct child_process *helper, exporter;
932 struct helper_data *data = transport->data;
933 struct string_list revlist_args = STRING_LIST_INIT_DUP;
934 struct strbuf buf = STRBUF_INIT;
935
936 if (!data->refspecs)
937 die("remote-helper doesn't support push; refspec needed");
938
939 set_common_push_options(transport, data->name, flags);
940 if (flags & TRANSPORT_PUSH_FORCE) {
941 if (set_helper_option(transport, "force", "true") != 0)
942 warning("helper %s does not support 'force'", data->name);
943 }
944
945 helper = get_helper(transport);
946
947 write_constant(helper->in, "export\n");
948
949 for (ref = remote_refs; ref; ref = ref->next) {
950 char *private;
951 struct object_id oid;
952
953 private = apply_refspecs(data->refspecs, data->refspec_nr, ref->name);
954 if (private && !get_oid(private, &oid)) {
955 strbuf_addf(&buf, "^%s", private);
956 string_list_append_nodup(&revlist_args,
957 strbuf_detach(&buf, NULL));
958 oidcpy(&ref->old_oid, &oid);
959 }
960 free(private);
961
962 if (ref->peer_ref) {
963 if (strcmp(ref->name, ref->peer_ref->name)) {
964 if (!ref->deletion) {
965 const char *name;
966 int flag;
967
968 /* Follow symbolic refs (mainly for HEAD). */
969 name = resolve_ref_unsafe(ref->peer_ref->name,
970 RESOLVE_REF_READING,
971 &oid, &flag);
972 if (!name || !(flag & REF_ISSYMREF))
973 name = ref->peer_ref->name;
974
975 strbuf_addf(&buf, "%s:%s", name, ref->name);
976 } else
977 strbuf_addf(&buf, ":%s", ref->name);
978
979 string_list_append(&revlist_args, "--refspec");
980 string_list_append(&revlist_args, buf.buf);
981 strbuf_release(&buf);
982 }
983 if (!ref->deletion)
984 string_list_append(&revlist_args, ref->peer_ref->name);
985 }
986 }
987
988 if (get_exporter(transport, &exporter, &revlist_args))
989 die("Couldn't run fast-export");
990
991 string_list_clear(&revlist_args, 1);
992
993 if (finish_command(&exporter))
994 die("Error while running fast-export");
995 if (push_update_refs_status(data, remote_refs, flags))
996 return 1;
997
998 if (data->export_marks) {
999 strbuf_addf(&buf, "%s.tmp", data->export_marks);
1000 rename(buf.buf, data->export_marks);
1001 strbuf_release(&buf);
1002 }
1003
1004 return 0;
1005}
1006
1007static int push_refs(struct transport *transport,
1008 struct ref *remote_refs, int flags)
1009{
1010 struct helper_data *data = transport->data;
1011
1012 if (process_connect(transport, 1)) {
1013 do_take_over(transport);
1014 return transport->vtable->push_refs(transport, remote_refs, flags);
1015 }
1016
1017 if (!remote_refs) {
1018 fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
1019 "Perhaps you should specify a branch such as 'master'.\n");
1020 return 0;
1021 }
1022
1023 if (data->push)
1024 return push_refs_with_push(transport, remote_refs, flags);
1025
1026 if (data->export)
1027 return push_refs_with_export(transport, remote_refs, flags);
1028
1029 return -1;
1030}
1031
1032
1033static int has_attribute(const char *attrs, const char *attr) {
1034 int len;
1035 if (!attrs)
1036 return 0;
1037
1038 len = strlen(attr);
1039 for (;;) {
1040 const char *space = strchrnul(attrs, ' ');
1041 if (len == space - attrs && !strncmp(attrs, attr, len))
1042 return 1;
1043 if (!*space)
1044 return 0;
1045 attrs = space + 1;
1046 }
1047}
1048
1049static struct ref *get_refs_list(struct transport *transport, int for_push,
1050 const struct argv_array *ref_prefixes)
1051{
1052 struct helper_data *data = transport->data;
1053 struct child_process *helper;
1054 struct ref *ret = NULL;
1055 struct ref **tail = &ret;
1056 struct ref *posn;
1057 struct strbuf buf = STRBUF_INIT;
1058
1059 helper = get_helper(transport);
1060
1061 if (process_connect(transport, for_push)) {
1062 do_take_over(transport);
1063 return transport->vtable->get_refs_list(transport, for_push, ref_prefixes);
1064 }
1065
1066 if (data->push && for_push)
1067 write_str_in_full(helper->in, "list for-push\n");
1068 else
1069 write_str_in_full(helper->in, "list\n");
1070
1071 while (1) {
1072 char *eov, *eon;
1073 if (recvline(data, &buf))
1074 exit(128);
1075
1076 if (!*buf.buf)
1077 break;
1078
1079 eov = strchr(buf.buf, ' ');
1080 if (!eov)
1081 die("Malformed response in ref list: %s", buf.buf);
1082 eon = strchr(eov + 1, ' ');
1083 *eov = '\0';
1084 if (eon)
1085 *eon = '\0';
1086 *tail = alloc_ref(eov + 1);
1087 if (buf.buf[0] == '@')
1088 (*tail)->symref = xstrdup(buf.buf + 1);
1089 else if (buf.buf[0] != '?')
1090 get_oid_hex(buf.buf, &(*tail)->old_oid);
1091 if (eon) {
1092 if (has_attribute(eon + 1, "unchanged")) {
1093 (*tail)->status |= REF_STATUS_UPTODATE;
1094 if (read_ref((*tail)->name, &(*tail)->old_oid) < 0)
1095 die(_("Could not read ref %s"),
1096 (*tail)->name);
1097 }
1098 }
1099 tail = &((*tail)->next);
1100 }
1101 if (debug)
1102 fprintf(stderr, "Debug: Read ref listing.\n");
1103 strbuf_release(&buf);
1104
1105 for (posn = ret; posn; posn = posn->next)
1106 resolve_remote_symref(posn, ret);
1107
1108 return ret;
1109}
1110
1111static struct transport_vtable vtable = {
1112 set_helper_option,
1113 get_refs_list,
1114 fetch,
1115 push_refs,
1116 connect_helper,
1117 release_helper
1118};
1119
1120int transport_helper_init(struct transport *transport, const char *name)
1121{
1122 struct helper_data *data = xcalloc(1, sizeof(*data));
1123 data->name = name;
1124
1125 transport_check_allowed(name);
1126
1127 if (getenv("GIT_TRANSPORT_HELPER_DEBUG"))
1128 debug = 1;
1129
1130 transport->data = data;
1131 transport->vtable = &vtable;
1132 transport->smart_options = &(data->transport_options);
1133 return 0;
1134}
1135
1136/*
1137 * Linux pipes can buffer 65536 bytes at once (and most platforms can
1138 * buffer less), so attempt reads and writes with up to that size.
1139 */
1140#define BUFFERSIZE 65536
1141/* This should be enough to hold debugging message. */
1142#define PBUFFERSIZE 8192
1143
1144/* Print bidirectional transfer loop debug message. */
1145__attribute__((format (printf, 1, 2)))
1146static void transfer_debug(const char *fmt, ...)
1147{
1148 /*
1149 * NEEDSWORK: This function is sometimes used from multiple threads, and
1150 * we end up using debug_enabled racily. That "should not matter" since
1151 * we always write the same value, but it's still wrong. This function
1152 * is listed in .tsan-suppressions for the time being.
1153 */
1154
1155 va_list args;
1156 char msgbuf[PBUFFERSIZE];
1157 static int debug_enabled = -1;
1158
1159 if (debug_enabled < 0)
1160 debug_enabled = getenv("GIT_TRANSLOOP_DEBUG") ? 1 : 0;
1161 if (!debug_enabled)
1162 return;
1163
1164 va_start(args, fmt);
1165 vsnprintf(msgbuf, PBUFFERSIZE, fmt, args);
1166 va_end(args);
1167 fprintf(stderr, "Transfer loop debugging: %s\n", msgbuf);
1168}
1169
1170/* Stream state: More data may be coming in this direction. */
1171#define SSTATE_TRANSFERRING 0
1172/*
1173 * Stream state: No more data coming in this direction, flushing rest of
1174 * data.
1175 */
1176#define SSTATE_FLUSHING 1
1177/* Stream state: Transfer in this direction finished. */
1178#define SSTATE_FINISHED 2
1179
1180#define STATE_NEEDS_READING(state) ((state) <= SSTATE_TRANSFERRING)
1181#define STATE_NEEDS_WRITING(state) ((state) <= SSTATE_FLUSHING)
1182#define STATE_NEEDS_CLOSING(state) ((state) == SSTATE_FLUSHING)
1183
1184/* Unidirectional transfer. */
1185struct unidirectional_transfer {
1186 /* Source */
1187 int src;
1188 /* Destination */
1189 int dest;
1190 /* Is source socket? */
1191 int src_is_sock;
1192 /* Is destination socket? */
1193 int dest_is_sock;
1194 /* Transfer state (TRANSFERRING/FLUSHING/FINISHED) */
1195 int state;
1196 /* Buffer. */
1197 char buf[BUFFERSIZE];
1198 /* Buffer used. */
1199 size_t bufuse;
1200 /* Name of source. */
1201 const char *src_name;
1202 /* Name of destination. */
1203 const char *dest_name;
1204};
1205
1206/* Closes the target (for writing) if transfer has finished. */
1207static void udt_close_if_finished(struct unidirectional_transfer *t)
1208{
1209 if (STATE_NEEDS_CLOSING(t->state) && !t->bufuse) {
1210 t->state = SSTATE_FINISHED;
1211 if (t->dest_is_sock)
1212 shutdown(t->dest, SHUT_WR);
1213 else
1214 close(t->dest);
1215 transfer_debug("Closed %s.", t->dest_name);
1216 }
1217}
1218
1219/*
1220 * Tries to read data from source into buffer. If buffer is full,
1221 * no data is read. Returns 0 on success, -1 on error.
1222 */
1223static int udt_do_read(struct unidirectional_transfer *t)
1224{
1225 ssize_t bytes;
1226
1227 if (t->bufuse == BUFFERSIZE)
1228 return 0; /* No space for more. */
1229
1230 transfer_debug("%s is readable", t->src_name);
1231 bytes = read(t->src, t->buf + t->bufuse, BUFFERSIZE - t->bufuse);
1232 if (bytes < 0 && errno != EWOULDBLOCK && errno != EAGAIN &&
1233 errno != EINTR) {
1234 error_errno("read(%s) failed", t->src_name);
1235 return -1;
1236 } else if (bytes == 0) {
1237 transfer_debug("%s EOF (with %i bytes in buffer)",
1238 t->src_name, (int)t->bufuse);
1239 t->state = SSTATE_FLUSHING;
1240 } else if (bytes > 0) {
1241 t->bufuse += bytes;
1242 transfer_debug("Read %i bytes from %s (buffer now at %i)",
1243 (int)bytes, t->src_name, (int)t->bufuse);
1244 }
1245 return 0;
1246}
1247
1248/* Tries to write data from buffer into destination. If buffer is empty,
1249 * no data is written. Returns 0 on success, -1 on error.
1250 */
1251static int udt_do_write(struct unidirectional_transfer *t)
1252{
1253 ssize_t bytes;
1254
1255 if (t->bufuse == 0)
1256 return 0; /* Nothing to write. */
1257
1258 transfer_debug("%s is writable", t->dest_name);
1259 bytes = xwrite(t->dest, t->buf, t->bufuse);
1260 if (bytes < 0 && errno != EWOULDBLOCK) {
1261 error_errno("write(%s) failed", t->dest_name);
1262 return -1;
1263 } else if (bytes > 0) {
1264 t->bufuse -= bytes;
1265 if (t->bufuse)
1266 memmove(t->buf, t->buf + bytes, t->bufuse);
1267 transfer_debug("Wrote %i bytes to %s (buffer now at %i)",
1268 (int)bytes, t->dest_name, (int)t->bufuse);
1269 }
1270 return 0;
1271}
1272
1273
1274/* State of bidirectional transfer loop. */
1275struct bidirectional_transfer_state {
1276 /* Direction from program to git. */
1277 struct unidirectional_transfer ptg;
1278 /* Direction from git to program. */
1279 struct unidirectional_transfer gtp;
1280};
1281
1282static void *udt_copy_task_routine(void *udt)
1283{
1284 struct unidirectional_transfer *t = (struct unidirectional_transfer *)udt;
1285 while (t->state != SSTATE_FINISHED) {
1286 if (STATE_NEEDS_READING(t->state))
1287 if (udt_do_read(t))
1288 return NULL;
1289 if (STATE_NEEDS_WRITING(t->state))
1290 if (udt_do_write(t))
1291 return NULL;
1292 if (STATE_NEEDS_CLOSING(t->state))
1293 udt_close_if_finished(t);
1294 }
1295 return udt; /* Just some non-NULL value. */
1296}
1297
1298#ifndef NO_PTHREADS
1299
1300/*
1301 * Join thread, with appropriate errors on failure. Name is name for the
1302 * thread (for error messages). Returns 0 on success, 1 on failure.
1303 */
1304static int tloop_join(pthread_t thread, const char *name)
1305{
1306 int err;
1307 void *tret;
1308 err = pthread_join(thread, &tret);
1309 if (!tret) {
1310 error("%s thread failed", name);
1311 return 1;
1312 }
1313 if (err) {
1314 error("%s thread failed to join: %s", name, strerror(err));
1315 return 1;
1316 }
1317 return 0;
1318}
1319
1320/*
1321 * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1322 * -1 on failure.
1323 */
1324static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1325{
1326 pthread_t gtp_thread;
1327 pthread_t ptg_thread;
1328 int err;
1329 int ret = 0;
1330 err = pthread_create(>p_thread, NULL, udt_copy_task_routine,
1331 &s->gtp);
1332 if (err)
1333 die("Can't start thread for copying data: %s", strerror(err));
1334 err = pthread_create(&ptg_thread, NULL, udt_copy_task_routine,
1335 &s->ptg);
1336 if (err)
1337 die("Can't start thread for copying data: %s", strerror(err));
1338
1339 ret |= tloop_join(gtp_thread, "Git to program copy");
1340 ret |= tloop_join(ptg_thread, "Program to git copy");
1341 return ret;
1342}
1343#else
1344
1345/* Close the source and target (for writing) for transfer. */
1346static void udt_kill_transfer(struct unidirectional_transfer *t)
1347{
1348 t->state = SSTATE_FINISHED;
1349 /*
1350 * Socket read end left open isn't a disaster if nobody
1351 * attempts to read from it (mingw compat headers do not
1352 * have SHUT_RD)...
1353 *
1354 * We can't fully close the socket since otherwise gtp
1355 * task would first close the socket it sends data to
1356 * while closing the ptg file descriptors.
1357 */
1358 if (!t->src_is_sock)
1359 close(t->src);
1360 if (t->dest_is_sock)
1361 shutdown(t->dest, SHUT_WR);
1362 else
1363 close(t->dest);
1364}
1365
1366/*
1367 * Join process, with appropriate errors on failure. Name is name for the
1368 * process (for error messages). Returns 0 on success, 1 on failure.
1369 */
1370static int tloop_join(pid_t pid, const char *name)
1371{
1372 int tret;
1373 if (waitpid(pid, &tret, 0) < 0) {
1374 error_errno("%s process failed to wait", name);
1375 return 1;
1376 }
1377 if (!WIFEXITED(tret) || WEXITSTATUS(tret)) {
1378 error("%s process failed", name);
1379 return 1;
1380 }
1381 return 0;
1382}
1383
1384/*
1385 * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1386 * -1 on failure.
1387 */
1388static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1389{
1390 pid_t pid1, pid2;
1391 int ret = 0;
1392
1393 /* Fork thread #1: git to program. */
1394 pid1 = fork();
1395 if (pid1 < 0)
1396 die_errno("Can't start thread for copying data");
1397 else if (pid1 == 0) {
1398 udt_kill_transfer(&s->ptg);
1399 exit(udt_copy_task_routine(&s->gtp) ? 0 : 1);
1400 }
1401
1402 /* Fork thread #2: program to git. */
1403 pid2 = fork();
1404 if (pid2 < 0)
1405 die_errno("Can't start thread for copying data");
1406 else if (pid2 == 0) {
1407 udt_kill_transfer(&s->gtp);
1408 exit(udt_copy_task_routine(&s->ptg) ? 0 : 1);
1409 }
1410
1411 /*
1412 * Close both streams in parent as to not interfere with
1413 * end of file detection and wait for both tasks to finish.
1414 */
1415 udt_kill_transfer(&s->gtp);
1416 udt_kill_transfer(&s->ptg);
1417 ret |= tloop_join(pid1, "Git to program copy");
1418 ret |= tloop_join(pid2, "Program to git copy");
1419 return ret;
1420}
1421#endif
1422
1423/*
1424 * Copies data from stdin to output and from input to stdout simultaneously.
1425 * Additionally filtering through given filter. If filter is NULL, uses
1426 * identity filter.
1427 */
1428int bidirectional_transfer_loop(int input, int output)
1429{
1430 struct bidirectional_transfer_state state;
1431
1432 /* Fill the state fields. */
1433 state.ptg.src = input;
1434 state.ptg.dest = 1;
1435 state.ptg.src_is_sock = (input == output);
1436 state.ptg.dest_is_sock = 0;
1437 state.ptg.state = SSTATE_TRANSFERRING;
1438 state.ptg.bufuse = 0;
1439 state.ptg.src_name = "remote input";
1440 state.ptg.dest_name = "stdout";
1441
1442 state.gtp.src = 0;
1443 state.gtp.dest = output;
1444 state.gtp.src_is_sock = 0;
1445 state.gtp.dest_is_sock = (input == output);
1446 state.gtp.state = SSTATE_TRANSFERRING;
1447 state.gtp.bufuse = 0;
1448 state.gtp.src_name = "stdin";
1449 state.gtp.dest_name = "remote output";
1450
1451 return tloop_spawnwait_tasks(&state);
1452}