standardize brace placement in struct definitions
[git/git.git] / transport-helper.c
1 #include "cache.h"
2 #include "transport.h"
3 #include "quote.h"
4 #include "run-command.h"
5 #include "commit.h"
6 #include "diff.h"
7 #include "revision.h"
8 #include "quote.h"
9 #include "remote.h"
10 #include "string-list.h"
11 #include "thread-utils.h"
12
13 static int debug;
14
15 struct helper_data {
16 const char *name;
17 struct child_process *helper;
18 FILE *out;
19 unsigned fetch : 1,
20 import : 1,
21 export : 1,
22 option : 1,
23 push : 1,
24 connect : 1,
25 no_disconnect_req : 1;
26 /* These go from remote name (as in "list") to private name */
27 struct refspec *refspecs;
28 int refspec_nr;
29 /* Transport options for fetch-pack/send-pack (should one of
30 * those be invoked).
31 */
32 struct git_transport_options transport_options;
33 };
34
35 static void sendline(struct helper_data *helper, struct strbuf *buffer)
36 {
37 if (debug)
38 fprintf(stderr, "Debug: Remote helper: -> %s", buffer->buf);
39 if (write_in_full(helper->helper->in, buffer->buf, buffer->len)
40 != buffer->len)
41 die_errno("Full write to remote helper failed");
42 }
43
44 static int recvline_fh(FILE *helper, struct strbuf *buffer)
45 {
46 strbuf_reset(buffer);
47 if (debug)
48 fprintf(stderr, "Debug: Remote helper: Waiting...\n");
49 if (strbuf_getline(buffer, helper, '\n') == EOF) {
50 if (debug)
51 fprintf(stderr, "Debug: Remote helper quit.\n");
52 exit(128);
53 }
54
55 if (debug)
56 fprintf(stderr, "Debug: Remote helper: <- %s\n", buffer->buf);
57 return 0;
58 }
59
60 static int recvline(struct helper_data *helper, struct strbuf *buffer)
61 {
62 return recvline_fh(helper->out, buffer);
63 }
64
65 static void xchgline(struct helper_data *helper, struct strbuf *buffer)
66 {
67 sendline(helper, buffer);
68 recvline(helper, buffer);
69 }
70
71 static void write_constant(int fd, const char *str)
72 {
73 if (debug)
74 fprintf(stderr, "Debug: Remote helper: -> %s", str);
75 if (write_in_full(fd, str, strlen(str)) != strlen(str))
76 die_errno("Full write to remote helper failed");
77 }
78
79 const char *remove_ext_force(const char *url)
80 {
81 if (url) {
82 const char *colon = strchr(url, ':');
83 if (colon && colon[1] == ':')
84 return colon + 2;
85 }
86 return url;
87 }
88
89 static void do_take_over(struct transport *transport)
90 {
91 struct helper_data *data;
92 data = (struct helper_data *)transport->data;
93 transport_take_over(transport, data->helper);
94 fclose(data->out);
95 free(data);
96 }
97
98 static struct child_process *get_helper(struct transport *transport)
99 {
100 struct helper_data *data = transport->data;
101 struct strbuf buf = STRBUF_INIT;
102 struct child_process *helper;
103 const char **refspecs = NULL;
104 int refspec_nr = 0;
105 int refspec_alloc = 0;
106 int duped;
107 int code;
108
109 if (data->helper)
110 return data->helper;
111
112 helper = xcalloc(1, sizeof(*helper));
113 helper->in = -1;
114 helper->out = -1;
115 helper->err = 0;
116 helper->argv = xcalloc(4, sizeof(*helper->argv));
117 strbuf_addf(&buf, "git-remote-%s", data->name);
118 helper->argv[0] = strbuf_detach(&buf, NULL);
119 helper->argv[1] = transport->remote->name;
120 helper->argv[2] = remove_ext_force(transport->url);
121 helper->git_cmd = 0;
122 helper->silent_exec_failure = 1;
123 code = start_command(helper);
124 if (code < 0 && errno == ENOENT)
125 die("Unable to find remote helper for '%s'", data->name);
126 else if (code != 0)
127 exit(code);
128
129 data->helper = helper;
130 data->no_disconnect_req = 0;
131
132 /*
133 * Open the output as FILE* so strbuf_getline() can be used.
134 * Do this with duped fd because fclose() will close the fd,
135 * and stuff like taking over will require the fd to remain.
136 */
137 duped = dup(helper->out);
138 if (duped < 0)
139 die_errno("Can't dup helper output fd");
140 data->out = xfdopen(duped, "r");
141
142 write_constant(helper->in, "capabilities\n");
143
144 while (1) {
145 const char *capname;
146 int mandatory = 0;
147 recvline(data, &buf);
148
149 if (!*buf.buf)
150 break;
151
152 if (*buf.buf == '*') {
153 capname = buf.buf + 1;
154 mandatory = 1;
155 } else
156 capname = buf.buf;
157
158 if (debug)
159 fprintf(stderr, "Debug: Got cap %s\n", capname);
160 if (!strcmp(capname, "fetch"))
161 data->fetch = 1;
162 else if (!strcmp(capname, "option"))
163 data->option = 1;
164 else if (!strcmp(capname, "push"))
165 data->push = 1;
166 else if (!strcmp(capname, "import"))
167 data->import = 1;
168 else if (!strcmp(capname, "export"))
169 data->export = 1;
170 else if (!data->refspecs && !prefixcmp(capname, "refspec ")) {
171 ALLOC_GROW(refspecs,
172 refspec_nr + 1,
173 refspec_alloc);
174 refspecs[refspec_nr++] = strdup(buf.buf + strlen("refspec "));
175 } else if (!strcmp(capname, "connect")) {
176 data->connect = 1;
177 } else if (!strcmp(buf.buf, "gitdir")) {
178 struct strbuf gitdir = STRBUF_INIT;
179 strbuf_addf(&gitdir, "gitdir %s\n", get_git_dir());
180 sendline(data, &gitdir);
181 strbuf_release(&gitdir);
182 } else if (mandatory) {
183 die("Unknown mandatory capability %s. This remote "
184 "helper probably needs newer version of Git.\n",
185 capname);
186 }
187 }
188 if (refspecs) {
189 int i;
190 data->refspec_nr = refspec_nr;
191 data->refspecs = parse_fetch_refspec(refspec_nr, refspecs);
192 for (i = 0; i < refspec_nr; i++) {
193 free((char *)refspecs[i]);
194 }
195 free(refspecs);
196 }
197 strbuf_release(&buf);
198 if (debug)
199 fprintf(stderr, "Debug: Capabilities complete.\n");
200 return data->helper;
201 }
202
203 static int disconnect_helper(struct transport *transport)
204 {
205 struct helper_data *data = transport->data;
206 struct strbuf buf = STRBUF_INIT;
207
208 if (data->helper) {
209 if (debug)
210 fprintf(stderr, "Debug: Disconnecting.\n");
211 if (!data->no_disconnect_req) {
212 strbuf_addf(&buf, "\n");
213 sendline(data, &buf);
214 }
215 close(data->helper->in);
216 close(data->helper->out);
217 fclose(data->out);
218 finish_command(data->helper);
219 free((char *)data->helper->argv[0]);
220 free(data->helper->argv);
221 free(data->helper);
222 data->helper = NULL;
223 }
224 return 0;
225 }
226
227 static const char *unsupported_options[] = {
228 TRANS_OPT_UPLOADPACK,
229 TRANS_OPT_RECEIVEPACK,
230 TRANS_OPT_THIN,
231 TRANS_OPT_KEEP
232 };
233 static const char *boolean_options[] = {
234 TRANS_OPT_THIN,
235 TRANS_OPT_KEEP,
236 TRANS_OPT_FOLLOWTAGS
237 };
238
239 static int set_helper_option(struct transport *transport,
240 const char *name, const char *value)
241 {
242 struct helper_data *data = transport->data;
243 struct strbuf buf = STRBUF_INIT;
244 int i, ret, is_bool = 0;
245
246 get_helper(transport);
247
248 if (!data->option)
249 return 1;
250
251 for (i = 0; i < ARRAY_SIZE(unsupported_options); i++) {
252 if (!strcmp(name, unsupported_options[i]))
253 return 1;
254 }
255
256 for (i = 0; i < ARRAY_SIZE(boolean_options); i++) {
257 if (!strcmp(name, boolean_options[i])) {
258 is_bool = 1;
259 break;
260 }
261 }
262
263 strbuf_addf(&buf, "option %s ", name);
264 if (is_bool)
265 strbuf_addstr(&buf, value ? "true" : "false");
266 else
267 quote_c_style(value, &buf, NULL, 0);
268 strbuf_addch(&buf, '\n');
269
270 xchgline(data, &buf);
271
272 if (!strcmp(buf.buf, "ok"))
273 ret = 0;
274 else if (!prefixcmp(buf.buf, "error")) {
275 ret = -1;
276 } else if (!strcmp(buf.buf, "unsupported"))
277 ret = 1;
278 else {
279 warning("%s unexpectedly said: '%s'", data->name, buf.buf);
280 ret = 1;
281 }
282 strbuf_release(&buf);
283 return ret;
284 }
285
286 static void standard_options(struct transport *t)
287 {
288 char buf[16];
289 int n;
290 int v = t->verbose;
291
292 set_helper_option(t, "progress", t->progress ? "true" : "false");
293
294 n = snprintf(buf, sizeof(buf), "%d", v + 1);
295 if (n >= sizeof(buf))
296 die("impossibly large verbosity value");
297 set_helper_option(t, "verbosity", buf);
298 }
299
300 static int release_helper(struct transport *transport)
301 {
302 struct helper_data *data = transport->data;
303 free_refspec(data->refspec_nr, data->refspecs);
304 data->refspecs = NULL;
305 disconnect_helper(transport);
306 free(transport->data);
307 return 0;
308 }
309
310 static int fetch_with_fetch(struct transport *transport,
311 int nr_heads, struct ref **to_fetch)
312 {
313 struct helper_data *data = transport->data;
314 int i;
315 struct strbuf buf = STRBUF_INIT;
316
317 standard_options(transport);
318
319 for (i = 0; i < nr_heads; i++) {
320 const struct ref *posn = to_fetch[i];
321 if (posn->status & REF_STATUS_UPTODATE)
322 continue;
323
324 strbuf_addf(&buf, "fetch %s %s\n",
325 sha1_to_hex(posn->old_sha1), posn->name);
326 }
327
328 strbuf_addch(&buf, '\n');
329 sendline(data, &buf);
330
331 while (1) {
332 recvline(data, &buf);
333
334 if (!prefixcmp(buf.buf, "lock ")) {
335 const char *name = buf.buf + 5;
336 if (transport->pack_lockfile)
337 warning("%s also locked %s", data->name, name);
338 else
339 transport->pack_lockfile = xstrdup(name);
340 }
341 else if (!buf.len)
342 break;
343 else
344 warning("%s unexpectedly said: '%s'", data->name, buf.buf);
345 }
346 strbuf_release(&buf);
347 return 0;
348 }
349
350 static int get_importer(struct transport *transport, struct child_process *fastimport)
351 {
352 struct child_process *helper = get_helper(transport);
353 memset(fastimport, 0, sizeof(*fastimport));
354 fastimport->in = helper->out;
355 fastimport->argv = xcalloc(5, sizeof(*fastimport->argv));
356 fastimport->argv[0] = "fast-import";
357 fastimport->argv[1] = "--quiet";
358
359 fastimport->git_cmd = 1;
360 return start_command(fastimport);
361 }
362
363 static int get_exporter(struct transport *transport,
364 struct child_process *fastexport,
365 const char *export_marks,
366 const char *import_marks,
367 struct string_list *revlist_args)
368 {
369 struct child_process *helper = get_helper(transport);
370 int argc = 0, i;
371 memset(fastexport, 0, sizeof(*fastexport));
372
373 /* we need to duplicate helper->in because we want to use it after
374 * fastexport is done with it. */
375 fastexport->out = dup(helper->in);
376 fastexport->argv = xcalloc(4 + revlist_args->nr, sizeof(*fastexport->argv));
377 fastexport->argv[argc++] = "fast-export";
378 if (export_marks)
379 fastexport->argv[argc++] = export_marks;
380 if (import_marks)
381 fastexport->argv[argc++] = import_marks;
382
383 for (i = 0; i < revlist_args->nr; i++)
384 fastexport->argv[argc++] = revlist_args->items[i].string;
385
386 fastexport->git_cmd = 1;
387 return start_command(fastexport);
388 }
389
390 static int fetch_with_import(struct transport *transport,
391 int nr_heads, struct ref **to_fetch)
392 {
393 struct child_process fastimport;
394 struct helper_data *data = transport->data;
395 int i;
396 struct ref *posn;
397 struct strbuf buf = STRBUF_INIT;
398
399 get_helper(transport);
400
401 if (get_importer(transport, &fastimport))
402 die("Couldn't run fast-import");
403
404 for (i = 0; i < nr_heads; i++) {
405 posn = to_fetch[i];
406 if (posn->status & REF_STATUS_UPTODATE)
407 continue;
408
409 strbuf_addf(&buf, "import %s\n", posn->name);
410 sendline(data, &buf);
411 strbuf_reset(&buf);
412 }
413 disconnect_helper(transport);
414 finish_command(&fastimport);
415 free(fastimport.argv);
416 fastimport.argv = NULL;
417
418 for (i = 0; i < nr_heads; i++) {
419 char *private;
420 posn = to_fetch[i];
421 if (posn->status & REF_STATUS_UPTODATE)
422 continue;
423 if (data->refspecs)
424 private = apply_refspecs(data->refspecs, data->refspec_nr, posn->name);
425 else
426 private = strdup(posn->name);
427 read_ref(private, posn->old_sha1);
428 free(private);
429 }
430 strbuf_release(&buf);
431 return 0;
432 }
433
434 static int process_connect_service(struct transport *transport,
435 const char *name, const char *exec)
436 {
437 struct helper_data *data = transport->data;
438 struct strbuf cmdbuf = STRBUF_INIT;
439 struct child_process *helper;
440 int r, duped, ret = 0;
441 FILE *input;
442
443 helper = get_helper(transport);
444
445 /*
446 * Yes, dup the pipe another time, as we need unbuffered version
447 * of input pipe as FILE*. fclose() closes the underlying fd and
448 * stream buffering only can be changed before first I/O operation
449 * on it.
450 */
451 duped = dup(helper->out);
452 if (duped < 0)
453 die_errno("Can't dup helper output fd");
454 input = xfdopen(duped, "r");
455 setvbuf(input, NULL, _IONBF, 0);
456
457 /*
458 * Handle --upload-pack and friends. This is fire and forget...
459 * just warn if it fails.
460 */
461 if (strcmp(name, exec)) {
462 r = set_helper_option(transport, "servpath", exec);
463 if (r > 0)
464 warning("Setting remote service path not supported by protocol.");
465 else if (r < 0)
466 warning("Invalid remote service path.");
467 }
468
469 if (data->connect)
470 strbuf_addf(&cmdbuf, "connect %s\n", name);
471 else
472 goto exit;
473
474 sendline(data, &cmdbuf);
475 recvline_fh(input, &cmdbuf);
476 if (!strcmp(cmdbuf.buf, "")) {
477 data->no_disconnect_req = 1;
478 if (debug)
479 fprintf(stderr, "Debug: Smart transport connection "
480 "ready.\n");
481 ret = 1;
482 } else if (!strcmp(cmdbuf.buf, "fallback")) {
483 if (debug)
484 fprintf(stderr, "Debug: Falling back to dumb "
485 "transport.\n");
486 } else
487 die("Unknown response to connect: %s",
488 cmdbuf.buf);
489
490 exit:
491 fclose(input);
492 return ret;
493 }
494
495 static int process_connect(struct transport *transport,
496 int for_push)
497 {
498 struct helper_data *data = transport->data;
499 const char *name;
500 const char *exec;
501
502 name = for_push ? "git-receive-pack" : "git-upload-pack";
503 if (for_push)
504 exec = data->transport_options.receivepack;
505 else
506 exec = data->transport_options.uploadpack;
507
508 return process_connect_service(transport, name, exec);
509 }
510
511 static int connect_helper(struct transport *transport, const char *name,
512 const char *exec, int fd[2])
513 {
514 struct helper_data *data = transport->data;
515
516 /* Get_helper so connect is inited. */
517 get_helper(transport);
518 if (!data->connect)
519 die("Operation not supported by protocol.");
520
521 if (!process_connect_service(transport, name, exec))
522 die("Can't connect to subservice %s.", name);
523
524 fd[0] = data->helper->out;
525 fd[1] = data->helper->in;
526 return 0;
527 }
528
529 static int fetch(struct transport *transport,
530 int nr_heads, struct ref **to_fetch)
531 {
532 struct helper_data *data = transport->data;
533 int i, count;
534
535 if (process_connect(transport, 0)) {
536 do_take_over(transport);
537 return transport->fetch(transport, nr_heads, to_fetch);
538 }
539
540 count = 0;
541 for (i = 0; i < nr_heads; i++)
542 if (!(to_fetch[i]->status & REF_STATUS_UPTODATE))
543 count++;
544
545 if (!count)
546 return 0;
547
548 if (data->fetch)
549 return fetch_with_fetch(transport, nr_heads, to_fetch);
550
551 if (data->import)
552 return fetch_with_import(transport, nr_heads, to_fetch);
553
554 return -1;
555 }
556
557 static int push_refs_with_push(struct transport *transport,
558 struct ref *remote_refs, int flags)
559 {
560 int force_all = flags & TRANSPORT_PUSH_FORCE;
561 int mirror = flags & TRANSPORT_PUSH_MIRROR;
562 struct helper_data *data = transport->data;
563 struct strbuf buf = STRBUF_INIT;
564 struct child_process *helper;
565 struct ref *ref;
566
567 helper = get_helper(transport);
568 if (!data->push)
569 return 1;
570
571 for (ref = remote_refs; ref; ref = ref->next) {
572 if (!ref->peer_ref && !mirror)
573 continue;
574
575 /* Check for statuses set by set_ref_status_for_push() */
576 switch (ref->status) {
577 case REF_STATUS_REJECT_NONFASTFORWARD:
578 case REF_STATUS_UPTODATE:
579 continue;
580 default:
581 ; /* do nothing */
582 }
583
584 if (force_all)
585 ref->force = 1;
586
587 strbuf_addstr(&buf, "push ");
588 if (!ref->deletion) {
589 if (ref->force)
590 strbuf_addch(&buf, '+');
591 if (ref->peer_ref)
592 strbuf_addstr(&buf, ref->peer_ref->name);
593 else
594 strbuf_addstr(&buf, sha1_to_hex(ref->new_sha1));
595 }
596 strbuf_addch(&buf, ':');
597 strbuf_addstr(&buf, ref->name);
598 strbuf_addch(&buf, '\n');
599 }
600 if (buf.len == 0)
601 return 0;
602
603 standard_options(transport);
604
605 if (flags & TRANSPORT_PUSH_DRY_RUN) {
606 if (set_helper_option(transport, "dry-run", "true") != 0)
607 die("helper %s does not support dry-run", data->name);
608 }
609
610 strbuf_addch(&buf, '\n');
611 sendline(data, &buf);
612
613 ref = remote_refs;
614 while (1) {
615 char *refname, *msg;
616 int status;
617
618 recvline(data, &buf);
619 if (!buf.len)
620 break;
621
622 if (!prefixcmp(buf.buf, "ok ")) {
623 status = REF_STATUS_OK;
624 refname = buf.buf + 3;
625 } else if (!prefixcmp(buf.buf, "error ")) {
626 status = REF_STATUS_REMOTE_REJECT;
627 refname = buf.buf + 6;
628 } else
629 die("expected ok/error, helper said '%s'\n", buf.buf);
630
631 msg = strchr(refname, ' ');
632 if (msg) {
633 struct strbuf msg_buf = STRBUF_INIT;
634 const char *end;
635
636 *msg++ = '\0';
637 if (!unquote_c_style(&msg_buf, msg, &end))
638 msg = strbuf_detach(&msg_buf, NULL);
639 else
640 msg = xstrdup(msg);
641 strbuf_release(&msg_buf);
642
643 if (!strcmp(msg, "no match")) {
644 status = REF_STATUS_NONE;
645 free(msg);
646 msg = NULL;
647 }
648 else if (!strcmp(msg, "up to date")) {
649 status = REF_STATUS_UPTODATE;
650 free(msg);
651 msg = NULL;
652 }
653 else if (!strcmp(msg, "non-fast forward")) {
654 status = REF_STATUS_REJECT_NONFASTFORWARD;
655 free(msg);
656 msg = NULL;
657 }
658 }
659
660 if (ref)
661 ref = find_ref_by_name(ref, refname);
662 if (!ref)
663 ref = find_ref_by_name(remote_refs, refname);
664 if (!ref) {
665 warning("helper reported unexpected status of %s", refname);
666 continue;
667 }
668
669 if (ref->status != REF_STATUS_NONE) {
670 /*
671 * Earlier, the ref was marked not to be pushed, so ignore the ref
672 * status reported by the remote helper if the latter is 'no match'.
673 */
674 if (status == REF_STATUS_NONE)
675 continue;
676 }
677
678 ref->status = status;
679 ref->remote_status = msg;
680 }
681 strbuf_release(&buf);
682 return 0;
683 }
684
685 static int push_refs_with_export(struct transport *transport,
686 struct ref *remote_refs, int flags)
687 {
688 struct ref *ref;
689 struct child_process *helper, exporter;
690 struct helper_data *data = transport->data;
691 char *export_marks = NULL, *import_marks = NULL;
692 struct string_list revlist_args = STRING_LIST_INIT_NODUP;
693 struct strbuf buf = STRBUF_INIT;
694
695 helper = get_helper(transport);
696
697 write_constant(helper->in, "export\n");
698
699 recvline(data, &buf);
700 if (debug)
701 fprintf(stderr, "Debug: Got export_marks '%s'\n", buf.buf);
702 if (buf.len) {
703 struct strbuf arg = STRBUF_INIT;
704 strbuf_addstr(&arg, "--export-marks=");
705 strbuf_addbuf(&arg, &buf);
706 export_marks = strbuf_detach(&arg, NULL);
707 }
708
709 recvline(data, &buf);
710 if (debug)
711 fprintf(stderr, "Debug: Got import_marks '%s'\n", buf.buf);
712 if (buf.len) {
713 struct strbuf arg = STRBUF_INIT;
714 strbuf_addstr(&arg, "--import-marks=");
715 strbuf_addbuf(&arg, &buf);
716 import_marks = strbuf_detach(&arg, NULL);
717 }
718
719 strbuf_reset(&buf);
720
721 for (ref = remote_refs; ref; ref = ref->next) {
722 char *private;
723 unsigned char sha1[20];
724
725 if (!data->refspecs)
726 continue;
727 private = apply_refspecs(data->refspecs, data->refspec_nr, ref->name);
728 if (private && !get_sha1(private, sha1)) {
729 strbuf_addf(&buf, "^%s", private);
730 string_list_append(&revlist_args, strbuf_detach(&buf, NULL));
731 }
732
733 string_list_append(&revlist_args, ref->name);
734
735 }
736
737 if (get_exporter(transport, &exporter,
738 export_marks, import_marks, &revlist_args))
739 die("Couldn't run fast-export");
740
741 data->no_disconnect_req = 1;
742 finish_command(&exporter);
743 disconnect_helper(transport);
744 return 0;
745 }
746
747 static int push_refs(struct transport *transport,
748 struct ref *remote_refs, int flags)
749 {
750 struct helper_data *data = transport->data;
751
752 if (process_connect(transport, 1)) {
753 do_take_over(transport);
754 return transport->push_refs(transport, remote_refs, flags);
755 }
756
757 if (!remote_refs) {
758 fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
759 "Perhaps you should specify a branch such as 'master'.\n");
760 return 0;
761 }
762
763 if (data->push)
764 return push_refs_with_push(transport, remote_refs, flags);
765
766 if (data->export)
767 return push_refs_with_export(transport, remote_refs, flags);
768
769 return -1;
770 }
771
772
773 static int has_attribute(const char *attrs, const char *attr) {
774 int len;
775 if (!attrs)
776 return 0;
777
778 len = strlen(attr);
779 for (;;) {
780 const char *space = strchrnul(attrs, ' ');
781 if (len == space - attrs && !strncmp(attrs, attr, len))
782 return 1;
783 if (!*space)
784 return 0;
785 attrs = space + 1;
786 }
787 }
788
789 static struct ref *get_refs_list(struct transport *transport, int for_push)
790 {
791 struct helper_data *data = transport->data;
792 struct child_process *helper;
793 struct ref *ret = NULL;
794 struct ref **tail = &ret;
795 struct ref *posn;
796 struct strbuf buf = STRBUF_INIT;
797
798 helper = get_helper(transport);
799
800 if (process_connect(transport, for_push)) {
801 do_take_over(transport);
802 return transport->get_refs_list(transport, for_push);
803 }
804
805 if (data->push && for_push)
806 write_str_in_full(helper->in, "list for-push\n");
807 else
808 write_str_in_full(helper->in, "list\n");
809
810 while (1) {
811 char *eov, *eon;
812 recvline(data, &buf);
813
814 if (!*buf.buf)
815 break;
816
817 eov = strchr(buf.buf, ' ');
818 if (!eov)
819 die("Malformed response in ref list: %s", buf.buf);
820 eon = strchr(eov + 1, ' ');
821 *eov = '\0';
822 if (eon)
823 *eon = '\0';
824 *tail = alloc_ref(eov + 1);
825 if (buf.buf[0] == '@')
826 (*tail)->symref = xstrdup(buf.buf + 1);
827 else if (buf.buf[0] != '?')
828 get_sha1_hex(buf.buf, (*tail)->old_sha1);
829 if (eon) {
830 if (has_attribute(eon + 1, "unchanged")) {
831 (*tail)->status |= REF_STATUS_UPTODATE;
832 read_ref((*tail)->name, (*tail)->old_sha1);
833 }
834 }
835 tail = &((*tail)->next);
836 }
837 if (debug)
838 fprintf(stderr, "Debug: Read ref listing.\n");
839 strbuf_release(&buf);
840
841 for (posn = ret; posn; posn = posn->next)
842 resolve_remote_symref(posn, ret);
843
844 return ret;
845 }
846
847 int transport_helper_init(struct transport *transport, const char *name)
848 {
849 struct helper_data *data = xcalloc(sizeof(*data), 1);
850 data->name = name;
851
852 if (getenv("GIT_TRANSPORT_HELPER_DEBUG"))
853 debug = 1;
854
855 transport->data = data;
856 transport->set_option = set_helper_option;
857 transport->get_refs_list = get_refs_list;
858 transport->fetch = fetch;
859 transport->push_refs = push_refs;
860 transport->disconnect = release_helper;
861 transport->connect = connect_helper;
862 transport->smart_options = &(data->transport_options);
863 return 0;
864 }
865
866 /*
867 * Linux pipes can buffer 65536 bytes at once (and most platforms can
868 * buffer less), so attempt reads and writes with up to that size.
869 */
870 #define BUFFERSIZE 65536
871 /* This should be enough to hold debugging message. */
872 #define PBUFFERSIZE 8192
873
874 /* Print bidirectional transfer loop debug message. */
875 static void transfer_debug(const char *fmt, ...)
876 {
877 va_list args;
878 char msgbuf[PBUFFERSIZE];
879 static int debug_enabled = -1;
880
881 if (debug_enabled < 0)
882 debug_enabled = getenv("GIT_TRANSLOOP_DEBUG") ? 1 : 0;
883 if (!debug_enabled)
884 return;
885
886 va_start(args, fmt);
887 vsnprintf(msgbuf, PBUFFERSIZE, fmt, args);
888 va_end(args);
889 fprintf(stderr, "Transfer loop debugging: %s\n", msgbuf);
890 }
891
892 /* Stream state: More data may be coming in this direction. */
893 #define SSTATE_TRANSFERING 0
894 /*
895 * Stream state: No more data coming in this direction, flushing rest of
896 * data.
897 */
898 #define SSTATE_FLUSHING 1
899 /* Stream state: Transfer in this direction finished. */
900 #define SSTATE_FINISHED 2
901
902 #define STATE_NEEDS_READING(state) ((state) <= SSTATE_TRANSFERING)
903 #define STATE_NEEDS_WRITING(state) ((state) <= SSTATE_FLUSHING)
904 #define STATE_NEEDS_CLOSING(state) ((state) == SSTATE_FLUSHING)
905
906 /* Unidirectional transfer. */
907 struct unidirectional_transfer {
908 /* Source */
909 int src;
910 /* Destination */
911 int dest;
912 /* Is source socket? */
913 int src_is_sock;
914 /* Is destination socket? */
915 int dest_is_sock;
916 /* Transfer state (TRANSFERING/FLUSHING/FINISHED) */
917 int state;
918 /* Buffer. */
919 char buf[BUFFERSIZE];
920 /* Buffer used. */
921 size_t bufuse;
922 /* Name of source. */
923 const char *src_name;
924 /* Name of destination. */
925 const char *dest_name;
926 };
927
928 /* Closes the target (for writing) if transfer has finished. */
929 static void udt_close_if_finished(struct unidirectional_transfer *t)
930 {
931 if (STATE_NEEDS_CLOSING(t->state) && !t->bufuse) {
932 t->state = SSTATE_FINISHED;
933 if (t->dest_is_sock)
934 shutdown(t->dest, SHUT_WR);
935 else
936 close(t->dest);
937 transfer_debug("Closed %s.", t->dest_name);
938 }
939 }
940
941 /*
942 * Tries to read read data from source into buffer. If buffer is full,
943 * no data is read. Returns 0 on success, -1 on error.
944 */
945 static int udt_do_read(struct unidirectional_transfer *t)
946 {
947 ssize_t bytes;
948
949 if (t->bufuse == BUFFERSIZE)
950 return 0; /* No space for more. */
951
952 transfer_debug("%s is readable", t->src_name);
953 bytes = read(t->src, t->buf + t->bufuse, BUFFERSIZE - t->bufuse);
954 if (bytes < 0 && errno != EWOULDBLOCK && errno != EAGAIN &&
955 errno != EINTR) {
956 error("read(%s) failed: %s", t->src_name, strerror(errno));
957 return -1;
958 } else if (bytes == 0) {
959 transfer_debug("%s EOF (with %i bytes in buffer)",
960 t->src_name, t->bufuse);
961 t->state = SSTATE_FLUSHING;
962 } else if (bytes > 0) {
963 t->bufuse += bytes;
964 transfer_debug("Read %i bytes from %s (buffer now at %i)",
965 (int)bytes, t->src_name, (int)t->bufuse);
966 }
967 return 0;
968 }
969
970 /* Tries to write data from buffer into destination. If buffer is empty,
971 * no data is written. Returns 0 on success, -1 on error.
972 */
973 static int udt_do_write(struct unidirectional_transfer *t)
974 {
975 size_t bytes;
976
977 if (t->bufuse == 0)
978 return 0; /* Nothing to write. */
979
980 transfer_debug("%s is writable", t->dest_name);
981 bytes = write(t->dest, t->buf, t->bufuse);
982 if (bytes < 0 && errno != EWOULDBLOCK && errno != EAGAIN &&
983 errno != EINTR) {
984 error("write(%s) failed: %s", t->dest_name, strerror(errno));
985 return -1;
986 } else if (bytes > 0) {
987 t->bufuse -= bytes;
988 if (t->bufuse)
989 memmove(t->buf, t->buf + bytes, t->bufuse);
990 transfer_debug("Wrote %i bytes to %s (buffer now at %i)",
991 (int)bytes, t->dest_name, (int)t->bufuse);
992 }
993 return 0;
994 }
995
996
997 /* State of bidirectional transfer loop. */
998 struct bidirectional_transfer_state {
999 /* Direction from program to git. */
1000 struct unidirectional_transfer ptg;
1001 /* Direction from git to program. */
1002 struct unidirectional_transfer gtp;
1003 };
1004
1005 static void *udt_copy_task_routine(void *udt)
1006 {
1007 struct unidirectional_transfer *t = (struct unidirectional_transfer *)udt;
1008 while (t->state != SSTATE_FINISHED) {
1009 if (STATE_NEEDS_READING(t->state))
1010 if (udt_do_read(t))
1011 return NULL;
1012 if (STATE_NEEDS_WRITING(t->state))
1013 if (udt_do_write(t))
1014 return NULL;
1015 if (STATE_NEEDS_CLOSING(t->state))
1016 udt_close_if_finished(t);
1017 }
1018 return udt; /* Just some non-NULL value. */
1019 }
1020
1021 #ifndef NO_PTHREADS
1022
1023 /*
1024 * Join thread, with apporiate errors on failure. Name is name for the
1025 * thread (for error messages). Returns 0 on success, 1 on failure.
1026 */
1027 static int tloop_join(pthread_t thread, const char *name)
1028 {
1029 int err;
1030 void *tret;
1031 err = pthread_join(thread, &tret);
1032 if (!tret) {
1033 error("%s thread failed", name);
1034 return 1;
1035 }
1036 if (err) {
1037 error("%s thread failed to join: %s", name, strerror(err));
1038 return 1;
1039 }
1040 return 0;
1041 }
1042
1043 /*
1044 * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1045 * -1 on failure.
1046 */
1047 static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1048 {
1049 pthread_t gtp_thread;
1050 pthread_t ptg_thread;
1051 int err;
1052 int ret = 0;
1053 err = pthread_create(&gtp_thread, NULL, udt_copy_task_routine,
1054 &s->gtp);
1055 if (err)
1056 die("Can't start thread for copying data: %s", strerror(err));
1057 err = pthread_create(&ptg_thread, NULL, udt_copy_task_routine,
1058 &s->ptg);
1059 if (err)
1060 die("Can't start thread for copying data: %s", strerror(err));
1061
1062 ret |= tloop_join(gtp_thread, "Git to program copy");
1063 ret |= tloop_join(ptg_thread, "Program to git copy");
1064 return ret;
1065 }
1066 #else
1067
1068 /* Close the source and target (for writing) for transfer. */
1069 static void udt_kill_transfer(struct unidirectional_transfer *t)
1070 {
1071 t->state = SSTATE_FINISHED;
1072 /*
1073 * Socket read end left open isn't a disaster if nobody
1074 * attempts to read from it (mingw compat headers do not
1075 * have SHUT_RD)...
1076 *
1077 * We can't fully close the socket since otherwise gtp
1078 * task would first close the socket it sends data to
1079 * while closing the ptg file descriptors.
1080 */
1081 if (!t->src_is_sock)
1082 close(t->src);
1083 if (t->dest_is_sock)
1084 shutdown(t->dest, SHUT_WR);
1085 else
1086 close(t->dest);
1087 }
1088
1089 /*
1090 * Join process, with apporiate errors on failure. Name is name for the
1091 * process (for error messages). Returns 0 on success, 1 on failure.
1092 */
1093 static int tloop_join(pid_t pid, const char *name)
1094 {
1095 int tret;
1096 if (waitpid(pid, &tret, 0) < 0) {
1097 error("%s process failed to wait: %s", name, strerror(errno));
1098 return 1;
1099 }
1100 if (!WIFEXITED(tret) || WEXITSTATUS(tret)) {
1101 error("%s process failed", name);
1102 return 1;
1103 }
1104 return 0;
1105 }
1106
1107 /*
1108 * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1109 * -1 on failure.
1110 */
1111 static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1112 {
1113 pid_t pid1, pid2;
1114 int ret = 0;
1115
1116 /* Fork thread #1: git to program. */
1117 pid1 = fork();
1118 if (pid1 < 0)
1119 die_errno("Can't start thread for copying data");
1120 else if (pid1 == 0) {
1121 udt_kill_transfer(&s->ptg);
1122 exit(udt_copy_task_routine(&s->gtp) ? 0 : 1);
1123 }
1124
1125 /* Fork thread #2: program to git. */
1126 pid2 = fork();
1127 if (pid2 < 0)
1128 die_errno("Can't start thread for copying data");
1129 else if (pid2 == 0) {
1130 udt_kill_transfer(&s->gtp);
1131 exit(udt_copy_task_routine(&s->ptg) ? 0 : 1);
1132 }
1133
1134 /*
1135 * Close both streams in parent as to not interfere with
1136 * end of file detection and wait for both tasks to finish.
1137 */
1138 udt_kill_transfer(&s->gtp);
1139 udt_kill_transfer(&s->ptg);
1140 ret |= tloop_join(pid1, "Git to program copy");
1141 ret |= tloop_join(pid2, "Program to git copy");
1142 return ret;
1143 }
1144 #endif
1145
1146 /*
1147 * Copies data from stdin to output and from input to stdout simultaneously.
1148 * Additionally filtering through given filter. If filter is NULL, uses
1149 * identity filter.
1150 */
1151 int bidirectional_transfer_loop(int input, int output)
1152 {
1153 struct bidirectional_transfer_state state;
1154
1155 /* Fill the state fields. */
1156 state.ptg.src = input;
1157 state.ptg.dest = 1;
1158 state.ptg.src_is_sock = (input == output);
1159 state.ptg.dest_is_sock = 0;
1160 state.ptg.state = SSTATE_TRANSFERING;
1161 state.ptg.bufuse = 0;
1162 state.ptg.src_name = "remote input";
1163 state.ptg.dest_name = "stdout";
1164
1165 state.gtp.src = 0;
1166 state.gtp.dest = output;
1167 state.gtp.src_is_sock = 0;
1168 state.gtp.dest_is_sock = (input == output);
1169 state.gtp.state = SSTATE_TRANSFERING;
1170 state.gtp.bufuse = 0;
1171 state.gtp.src_name = "stdin";
1172 state.gtp.dest_name = "remote output";
1173
1174 return tloop_spawnwait_tasks(&state);
1175 }