transport-helper: trivial style cleanup
[git/gitweb.git] / transport-helper.c
blobfdd79d8b35010ae7ed6515abc9a9fd7865a5851d
1 #include "cache.h"
2 #include "transport.h"
3 #include "quote.h"
4 #include "run-command.h"
5 #include "commit.h"
6 #include "diff.h"
7 #include "revision.h"
8 #include "quote.h"
9 #include "remote.h"
10 #include "string-list.h"
11 #include "thread-utils.h"
12 #include "sigchain.h"
13 #include "argv-array.h"
15 static int debug;
17 struct helper_data {
18 const char *name;
19 struct child_process *helper;
20 FILE *out;
21 unsigned fetch : 1,
22 import : 1,
23 bidi_import : 1,
24 export : 1,
25 option : 1,
26 push : 1,
27 connect : 1,
28 no_disconnect_req : 1;
29 char *export_marks;
30 char *import_marks;
31 /* These go from remote name (as in "list") to private name */
32 struct refspec *refspecs;
33 int refspec_nr;
34 /* Transport options for fetch-pack/send-pack (should one of
35 * those be invoked).
37 struct git_transport_options transport_options;
40 static void sendline(struct helper_data *helper, struct strbuf *buffer)
42 if (debug)
43 fprintf(stderr, "Debug: Remote helper: -> %s", buffer->buf);
44 if (write_in_full(helper->helper->in, buffer->buf, buffer->len)
45 != buffer->len)
46 die_errno("Full write to remote helper failed");
49 static int recvline_fh(FILE *helper, struct strbuf *buffer)
51 strbuf_reset(buffer);
52 if (debug)
53 fprintf(stderr, "Debug: Remote helper: Waiting...\n");
54 if (strbuf_getline(buffer, helper, '\n') == EOF) {
55 if (debug)
56 fprintf(stderr, "Debug: Remote helper quit.\n");
57 exit(128);
60 if (debug)
61 fprintf(stderr, "Debug: Remote helper: <- %s\n", buffer->buf);
62 return 0;
65 static int recvline(struct helper_data *helper, struct strbuf *buffer)
67 return recvline_fh(helper->out, buffer);
70 static void xchgline(struct helper_data *helper, struct strbuf *buffer)
72 sendline(helper, buffer);
73 recvline(helper, buffer);
76 static void write_constant(int fd, const char *str)
78 if (debug)
79 fprintf(stderr, "Debug: Remote helper: -> %s", str);
80 if (write_in_full(fd, str, strlen(str)) != strlen(str))
81 die_errno("Full write to remote helper failed");
84 static const char *remove_ext_force(const char *url)
86 if (url) {
87 const char *colon = strchr(url, ':');
88 if (colon && colon[1] == ':')
89 return colon + 2;
91 return url;
94 static void do_take_over(struct transport *transport)
96 struct helper_data *data;
97 data = (struct helper_data *)transport->data;
98 transport_take_over(transport, data->helper);
99 fclose(data->out);
100 free(data);
103 static struct child_process *get_helper(struct transport *transport)
105 struct helper_data *data = transport->data;
106 struct argv_array argv = ARGV_ARRAY_INIT;
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 char git_dir_buf[sizeof(GIT_DIR_ENVIRONMENT) + PATH_MAX + 1];
115 const char *helper_env[] = {
116 git_dir_buf,
117 NULL
121 if (data->helper)
122 return data->helper;
124 helper = xcalloc(1, sizeof(*helper));
125 helper->in = -1;
126 helper->out = -1;
127 helper->err = 0;
128 argv_array_pushf(&argv, "git-remote-%s", data->name);
129 argv_array_push(&argv, transport->remote->name);
130 argv_array_push(&argv, remove_ext_force(transport->url));
131 helper->argv = argv_array_detach(&argv, NULL);
132 helper->git_cmd = 0;
133 helper->silent_exec_failure = 1;
135 snprintf(git_dir_buf, sizeof(git_dir_buf), "%s=%s", GIT_DIR_ENVIRONMENT, get_git_dir());
136 helper->env = helper_env;
138 code = start_command(helper);
139 if (code < 0 && errno == ENOENT)
140 die("Unable to find remote helper for '%s'", data->name);
141 else if (code != 0)
142 exit(code);
144 data->helper = helper;
145 data->no_disconnect_req = 0;
148 * Open the output as FILE* so strbuf_getline() can be used.
149 * Do this with duped fd because fclose() will close the fd,
150 * and stuff like taking over will require the fd to remain.
152 duped = dup(helper->out);
153 if (duped < 0)
154 die_errno("Can't dup helper output fd");
155 data->out = xfdopen(duped, "r");
157 write_constant(helper->in, "capabilities\n");
159 while (1) {
160 const char *capname;
161 int mandatory = 0;
162 recvline(data, &buf);
164 if (!*buf.buf)
165 break;
167 if (*buf.buf == '*') {
168 capname = buf.buf + 1;
169 mandatory = 1;
170 } else
171 capname = buf.buf;
173 if (debug)
174 fprintf(stderr, "Debug: Got cap %s\n", capname);
175 if (!strcmp(capname, "fetch"))
176 data->fetch = 1;
177 else if (!strcmp(capname, "option"))
178 data->option = 1;
179 else if (!strcmp(capname, "push"))
180 data->push = 1;
181 else if (!strcmp(capname, "import"))
182 data->import = 1;
183 else if (!strcmp(capname, "bidi-import"))
184 data->bidi_import = 1;
185 else if (!strcmp(capname, "export"))
186 data->export = 1;
187 else if (!data->refspecs && !prefixcmp(capname, "refspec ")) {
188 ALLOC_GROW(refspecs,
189 refspec_nr + 1,
190 refspec_alloc);
191 refspecs[refspec_nr++] = xstrdup(capname + strlen("refspec "));
192 } else if (!strcmp(capname, "connect")) {
193 data->connect = 1;
194 } else if (!prefixcmp(capname, "export-marks ")) {
195 struct strbuf arg = STRBUF_INIT;
196 strbuf_addstr(&arg, "--export-marks=");
197 strbuf_addstr(&arg, capname + strlen("export-marks "));
198 data->export_marks = strbuf_detach(&arg, NULL);
199 } else if (!prefixcmp(capname, "import-marks")) {
200 struct strbuf arg = STRBUF_INIT;
201 strbuf_addstr(&arg, "--import-marks=");
202 strbuf_addstr(&arg, capname + strlen("import-marks "));
203 data->import_marks = strbuf_detach(&arg, NULL);
204 } else if (mandatory) {
205 die("Unknown mandatory capability %s. This remote "
206 "helper probably needs newer version of Git.",
207 capname);
210 if (refspecs) {
211 int i;
212 data->refspec_nr = refspec_nr;
213 data->refspecs = parse_fetch_refspec(refspec_nr, refspecs);
214 for (i = 0; i < refspec_nr; i++)
215 free((char *)refspecs[i]);
216 free(refspecs);
218 strbuf_release(&buf);
219 if (debug)
220 fprintf(stderr, "Debug: Capabilities complete.\n");
221 return data->helper;
224 static int disconnect_helper(struct transport *transport)
226 struct helper_data *data = transport->data;
227 int res = 0;
229 if (data->helper) {
230 if (debug)
231 fprintf(stderr, "Debug: Disconnecting.\n");
232 if (!data->no_disconnect_req) {
234 * Ignore write errors; there's nothing we can do,
235 * since we're about to close the pipe anyway. And the
236 * most likely error is EPIPE due to the helper dying
237 * to report an error itself.
239 sigchain_push(SIGPIPE, SIG_IGN);
240 xwrite(data->helper->in, "\n", 1);
241 sigchain_pop(SIGPIPE);
243 close(data->helper->in);
244 close(data->helper->out);
245 fclose(data->out);
246 res = finish_command(data->helper);
247 argv_array_free_detached(data->helper->argv);
248 free(data->helper);
249 data->helper = NULL;
251 return res;
254 static const char *unsupported_options[] = {
255 TRANS_OPT_UPLOADPACK,
256 TRANS_OPT_RECEIVEPACK,
257 TRANS_OPT_THIN,
258 TRANS_OPT_KEEP
260 static const char *boolean_options[] = {
261 TRANS_OPT_THIN,
262 TRANS_OPT_KEEP,
263 TRANS_OPT_FOLLOWTAGS
266 static int set_helper_option(struct transport *transport,
267 const char *name, const char *value)
269 struct helper_data *data = transport->data;
270 struct strbuf buf = STRBUF_INIT;
271 int i, ret, is_bool = 0;
273 get_helper(transport);
275 if (!data->option)
276 return 1;
278 for (i = 0; i < ARRAY_SIZE(unsupported_options); i++) {
279 if (!strcmp(name, unsupported_options[i]))
280 return 1;
283 for (i = 0; i < ARRAY_SIZE(boolean_options); i++) {
284 if (!strcmp(name, boolean_options[i])) {
285 is_bool = 1;
286 break;
290 strbuf_addf(&buf, "option %s ", name);
291 if (is_bool)
292 strbuf_addstr(&buf, value ? "true" : "false");
293 else
294 quote_c_style(value, &buf, NULL, 0);
295 strbuf_addch(&buf, '\n');
297 xchgline(data, &buf);
299 if (!strcmp(buf.buf, "ok"))
300 ret = 0;
301 else if (!prefixcmp(buf.buf, "error")) {
302 ret = -1;
303 } else if (!strcmp(buf.buf, "unsupported"))
304 ret = 1;
305 else {
306 warning("%s unexpectedly said: '%s'", data->name, buf.buf);
307 ret = 1;
309 strbuf_release(&buf);
310 return ret;
313 static void standard_options(struct transport *t)
315 char buf[16];
316 int n;
317 int v = t->verbose;
319 set_helper_option(t, "progress", t->progress ? "true" : "false");
321 n = snprintf(buf, sizeof(buf), "%d", v + 1);
322 if (n >= sizeof(buf))
323 die("impossibly large verbosity value");
324 set_helper_option(t, "verbosity", buf);
327 static int release_helper(struct transport *transport)
329 int res = 0;
330 struct helper_data *data = transport->data;
331 free_refspec(data->refspec_nr, data->refspecs);
332 data->refspecs = NULL;
333 res = disconnect_helper(transport);
334 free(transport->data);
335 return res;
338 static int fetch_with_fetch(struct transport *transport,
339 int nr_heads, struct ref **to_fetch)
341 struct helper_data *data = transport->data;
342 int i;
343 struct strbuf buf = STRBUF_INIT;
345 standard_options(transport);
347 for (i = 0; i < nr_heads; i++) {
348 const struct ref *posn = to_fetch[i];
349 if (posn->status & REF_STATUS_UPTODATE)
350 continue;
352 strbuf_addf(&buf, "fetch %s %s\n",
353 sha1_to_hex(posn->old_sha1), posn->name);
356 strbuf_addch(&buf, '\n');
357 sendline(data, &buf);
359 while (1) {
360 recvline(data, &buf);
362 if (!prefixcmp(buf.buf, "lock ")) {
363 const char *name = buf.buf + 5;
364 if (transport->pack_lockfile)
365 warning("%s also locked %s", data->name, name);
366 else
367 transport->pack_lockfile = xstrdup(name);
369 else if (!buf.len)
370 break;
371 else
372 warning("%s unexpectedly said: '%s'", data->name, buf.buf);
374 strbuf_release(&buf);
375 return 0;
378 static int get_importer(struct transport *transport, struct child_process *fastimport)
380 struct child_process *helper = get_helper(transport);
381 struct helper_data *data = transport->data;
382 struct argv_array argv = ARGV_ARRAY_INIT;
383 int cat_blob_fd, code;
384 memset(fastimport, 0, sizeof(*fastimport));
385 fastimport->in = helper->out;
386 argv_array_push(&argv, "fast-import");
387 argv_array_push(&argv, debug ? "--stats" : "--quiet");
389 if (data->bidi_import) {
390 cat_blob_fd = xdup(helper->in);
391 argv_array_pushf(&argv, "--cat-blob-fd=%d", cat_blob_fd);
393 fastimport->argv = argv.argv;
394 fastimport->git_cmd = 1;
396 code = start_command(fastimport);
397 return code;
400 static int get_exporter(struct transport *transport,
401 struct child_process *fastexport,
402 struct string_list *revlist_args)
404 struct helper_data *data = transport->data;
405 struct child_process *helper = get_helper(transport);
406 int argc = 0, i;
407 memset(fastexport, 0, sizeof(*fastexport));
409 /* we need to duplicate helper->in because we want to use it after
410 * fastexport is done with it. */
411 fastexport->out = dup(helper->in);
412 fastexport->argv = xcalloc(5 + revlist_args->nr, sizeof(*fastexport->argv));
413 fastexport->argv[argc++] = "fast-export";
414 fastexport->argv[argc++] = "--use-done-feature";
415 if (data->export_marks)
416 fastexport->argv[argc++] = data->export_marks;
417 if (data->import_marks)
418 fastexport->argv[argc++] = data->import_marks;
420 for (i = 0; i < revlist_args->nr; i++)
421 fastexport->argv[argc++] = revlist_args->items[i].string;
423 fastexport->git_cmd = 1;
424 return start_command(fastexport);
427 static int fetch_with_import(struct transport *transport,
428 int nr_heads, struct ref **to_fetch)
430 struct child_process fastimport;
431 struct helper_data *data = transport->data;
432 int i;
433 struct ref *posn;
434 struct strbuf buf = STRBUF_INIT;
436 get_helper(transport);
438 if (get_importer(transport, &fastimport))
439 die("Couldn't run fast-import");
441 for (i = 0; i < nr_heads; i++) {
442 posn = to_fetch[i];
443 if (posn->status & REF_STATUS_UPTODATE)
444 continue;
446 strbuf_addf(&buf, "import %s\n", posn->name);
447 sendline(data, &buf);
448 strbuf_reset(&buf);
451 write_constant(data->helper->in, "\n");
453 * remote-helpers that advertise the bidi-import capability are required to
454 * buffer the complete batch of import commands until this newline before
455 * sending data to fast-import.
456 * These helpers read back data from fast-import on their stdin, which could
457 * be mixed with import commands, otherwise.
460 if (finish_command(&fastimport))
461 die("Error while running fast-import");
462 argv_array_free_detached(fastimport.argv);
465 * The fast-import stream of a remote helper that advertises
466 * the "refspec" capability writes to the refs named after the
467 * right hand side of the first refspec matching each ref we
468 * were fetching.
470 * (If no "refspec" capability was specified, for historical
471 * reasons we default to *:*.)
473 * Store the result in to_fetch[i].old_sha1. Callers such
474 * as "git fetch" can use the value to write feedback to the
475 * terminal, populate FETCH_HEAD, and determine what new value
476 * should be written to peer_ref if the update is a
477 * fast-forward or this is a forced update.
479 for (i = 0; i < nr_heads; i++) {
480 char *private;
481 posn = to_fetch[i];
482 if (posn->status & REF_STATUS_UPTODATE)
483 continue;
484 if (data->refspecs)
485 private = apply_refspecs(data->refspecs, data->refspec_nr, posn->name);
486 else
487 private = xstrdup(posn->name);
488 if (private) {
489 read_ref(private, posn->old_sha1);
490 free(private);
493 strbuf_release(&buf);
494 return 0;
497 static int process_connect_service(struct transport *transport,
498 const char *name, const char *exec)
500 struct helper_data *data = transport->data;
501 struct strbuf cmdbuf = STRBUF_INIT;
502 struct child_process *helper;
503 int r, duped, ret = 0;
504 FILE *input;
506 helper = get_helper(transport);
509 * Yes, dup the pipe another time, as we need unbuffered version
510 * of input pipe as FILE*. fclose() closes the underlying fd and
511 * stream buffering only can be changed before first I/O operation
512 * on it.
514 duped = dup(helper->out);
515 if (duped < 0)
516 die_errno("Can't dup helper output fd");
517 input = xfdopen(duped, "r");
518 setvbuf(input, NULL, _IONBF, 0);
521 * Handle --upload-pack and friends. This is fire and forget...
522 * just warn if it fails.
524 if (strcmp(name, exec)) {
525 r = set_helper_option(transport, "servpath", exec);
526 if (r > 0)
527 warning("Setting remote service path not supported by protocol.");
528 else if (r < 0)
529 warning("Invalid remote service path.");
532 if (data->connect)
533 strbuf_addf(&cmdbuf, "connect %s\n", name);
534 else
535 goto exit;
537 sendline(data, &cmdbuf);
538 recvline_fh(input, &cmdbuf);
539 if (!strcmp(cmdbuf.buf, "")) {
540 data->no_disconnect_req = 1;
541 if (debug)
542 fprintf(stderr, "Debug: Smart transport connection "
543 "ready.\n");
544 ret = 1;
545 } else if (!strcmp(cmdbuf.buf, "fallback")) {
546 if (debug)
547 fprintf(stderr, "Debug: Falling back to dumb "
548 "transport.\n");
549 } else
550 die("Unknown response to connect: %s",
551 cmdbuf.buf);
553 exit:
554 fclose(input);
555 return ret;
558 static int process_connect(struct transport *transport,
559 int for_push)
561 struct helper_data *data = transport->data;
562 const char *name;
563 const char *exec;
565 name = for_push ? "git-receive-pack" : "git-upload-pack";
566 if (for_push)
567 exec = data->transport_options.receivepack;
568 else
569 exec = data->transport_options.uploadpack;
571 return process_connect_service(transport, name, exec);
574 static int connect_helper(struct transport *transport, const char *name,
575 const char *exec, int fd[2])
577 struct helper_data *data = transport->data;
579 /* Get_helper so connect is inited. */
580 get_helper(transport);
581 if (!data->connect)
582 die("Operation not supported by protocol.");
584 if (!process_connect_service(transport, name, exec))
585 die("Can't connect to subservice %s.", name);
587 fd[0] = data->helper->out;
588 fd[1] = data->helper->in;
589 return 0;
592 static int fetch(struct transport *transport,
593 int nr_heads, struct ref **to_fetch)
595 struct helper_data *data = transport->data;
596 int i, count;
598 if (process_connect(transport, 0)) {
599 do_take_over(transport);
600 return transport->fetch(transport, nr_heads, to_fetch);
603 count = 0;
604 for (i = 0; i < nr_heads; i++)
605 if (!(to_fetch[i]->status & REF_STATUS_UPTODATE))
606 count++;
608 if (!count)
609 return 0;
611 if (data->fetch)
612 return fetch_with_fetch(transport, nr_heads, to_fetch);
614 if (data->import)
615 return fetch_with_import(transport, nr_heads, to_fetch);
617 return -1;
620 static void push_update_ref_status(struct strbuf *buf,
621 struct ref **ref,
622 struct ref *remote_refs)
624 char *refname, *msg;
625 int status;
627 if (!prefixcmp(buf->buf, "ok ")) {
628 status = REF_STATUS_OK;
629 refname = buf->buf + 3;
630 } else if (!prefixcmp(buf->buf, "error ")) {
631 status = REF_STATUS_REMOTE_REJECT;
632 refname = buf->buf + 6;
633 } else
634 die("expected ok/error, helper said '%s'", buf->buf);
636 msg = strchr(refname, ' ');
637 if (msg) {
638 struct strbuf msg_buf = STRBUF_INIT;
639 const char *end;
641 *msg++ = '\0';
642 if (!unquote_c_style(&msg_buf, msg, &end))
643 msg = strbuf_detach(&msg_buf, NULL);
644 else
645 msg = xstrdup(msg);
646 strbuf_release(&msg_buf);
648 if (!strcmp(msg, "no match")) {
649 status = REF_STATUS_NONE;
650 free(msg);
651 msg = NULL;
653 else if (!strcmp(msg, "up to date")) {
654 status = REF_STATUS_UPTODATE;
655 free(msg);
656 msg = NULL;
658 else if (!strcmp(msg, "non-fast forward")) {
659 status = REF_STATUS_REJECT_NONFASTFORWARD;
660 free(msg);
661 msg = NULL;
663 else if (!strcmp(msg, "already exists")) {
664 status = REF_STATUS_REJECT_ALREADY_EXISTS;
665 free(msg);
666 msg = NULL;
668 else if (!strcmp(msg, "fetch first")) {
669 status = REF_STATUS_REJECT_FETCH_FIRST;
670 free(msg);
671 msg = NULL;
673 else if (!strcmp(msg, "needs force")) {
674 status = REF_STATUS_REJECT_NEEDS_FORCE;
675 free(msg);
676 msg = NULL;
680 if (*ref)
681 *ref = find_ref_by_name(*ref, refname);
682 if (!*ref)
683 *ref = find_ref_by_name(remote_refs, refname);
684 if (!*ref) {
685 warning("helper reported unexpected status of %s", refname);
686 return;
689 if ((*ref)->status != REF_STATUS_NONE) {
691 * Earlier, the ref was marked not to be pushed, so ignore the ref
692 * status reported by the remote helper if the latter is 'no match'.
694 if (status == REF_STATUS_NONE)
695 return;
698 (*ref)->status = status;
699 (*ref)->remote_status = msg;
702 static void push_update_refs_status(struct helper_data *data,
703 struct ref *remote_refs)
705 struct strbuf buf = STRBUF_INIT;
706 struct ref *ref = remote_refs;
707 for (;;) {
708 recvline(data, &buf);
709 if (!buf.len)
710 break;
712 push_update_ref_status(&buf, &ref, remote_refs);
714 strbuf_release(&buf);
717 static int push_refs_with_push(struct transport *transport,
718 struct ref *remote_refs, int flags)
720 int force_all = flags & TRANSPORT_PUSH_FORCE;
721 int mirror = flags & TRANSPORT_PUSH_MIRROR;
722 struct helper_data *data = transport->data;
723 struct strbuf buf = STRBUF_INIT;
724 struct ref *ref;
726 get_helper(transport);
727 if (!data->push)
728 return 1;
730 for (ref = remote_refs; ref; ref = ref->next) {
731 if (!ref->peer_ref && !mirror)
732 continue;
734 /* Check for statuses set by set_ref_status_for_push() */
735 switch (ref->status) {
736 case REF_STATUS_REJECT_NONFASTFORWARD:
737 case REF_STATUS_REJECT_ALREADY_EXISTS:
738 case REF_STATUS_UPTODATE:
739 continue;
740 default:
741 ; /* do nothing */
744 if (force_all)
745 ref->force = 1;
747 strbuf_addstr(&buf, "push ");
748 if (!ref->deletion) {
749 if (ref->force)
750 strbuf_addch(&buf, '+');
751 if (ref->peer_ref)
752 strbuf_addstr(&buf, ref->peer_ref->name);
753 else
754 strbuf_addstr(&buf, sha1_to_hex(ref->new_sha1));
756 strbuf_addch(&buf, ':');
757 strbuf_addstr(&buf, ref->name);
758 strbuf_addch(&buf, '\n');
760 if (buf.len == 0)
761 return 0;
763 standard_options(transport);
765 if (flags & TRANSPORT_PUSH_DRY_RUN) {
766 if (set_helper_option(transport, "dry-run", "true") != 0)
767 die("helper %s does not support dry-run", data->name);
770 strbuf_addch(&buf, '\n');
771 sendline(data, &buf);
772 strbuf_release(&buf);
774 push_update_refs_status(data, remote_refs);
775 return 0;
778 static int push_refs_with_export(struct transport *transport,
779 struct ref *remote_refs, int flags)
781 struct ref *ref;
782 struct child_process *helper, exporter;
783 struct helper_data *data = transport->data;
784 struct string_list revlist_args = STRING_LIST_INIT_NODUP;
785 struct strbuf buf = STRBUF_INIT;
787 helper = get_helper(transport);
789 write_constant(helper->in, "export\n");
791 strbuf_reset(&buf);
793 for (ref = remote_refs; ref; ref = ref->next) {
794 char *private;
795 unsigned char sha1[20];
797 if (!data->refspecs)
798 continue;
799 private = apply_refspecs(data->refspecs, data->refspec_nr, ref->name);
800 if (private && !get_sha1(private, sha1)) {
801 strbuf_addf(&buf, "^%s", private);
802 string_list_append(&revlist_args, strbuf_detach(&buf, NULL));
804 free(private);
806 if (ref->deletion) {
807 die("remote-helpers do not support ref deletion");
810 if (ref->peer_ref)
811 string_list_append(&revlist_args, ref->peer_ref->name);
815 if (get_exporter(transport, &exporter, &revlist_args))
816 die("Couldn't run fast-export");
818 if (finish_command(&exporter))
819 die("Error while running fast-export");
820 push_update_refs_status(data, remote_refs);
821 return 0;
824 static int push_refs(struct transport *transport,
825 struct ref *remote_refs, int flags)
827 struct helper_data *data = transport->data;
829 if (process_connect(transport, 1)) {
830 do_take_over(transport);
831 return transport->push_refs(transport, remote_refs, flags);
834 if (!remote_refs) {
835 fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
836 "Perhaps you should specify a branch such as 'master'.\n");
837 return 0;
840 if (data->push)
841 return push_refs_with_push(transport, remote_refs, flags);
843 if (data->export)
844 return push_refs_with_export(transport, remote_refs, flags);
846 return -1;
850 static int has_attribute(const char *attrs, const char *attr) {
851 int len;
852 if (!attrs)
853 return 0;
855 len = strlen(attr);
856 for (;;) {
857 const char *space = strchrnul(attrs, ' ');
858 if (len == space - attrs && !strncmp(attrs, attr, len))
859 return 1;
860 if (!*space)
861 return 0;
862 attrs = space + 1;
866 static struct ref *get_refs_list(struct transport *transport, int for_push)
868 struct helper_data *data = transport->data;
869 struct child_process *helper;
870 struct ref *ret = NULL;
871 struct ref **tail = &ret;
872 struct ref *posn;
873 struct strbuf buf = STRBUF_INIT;
875 helper = get_helper(transport);
877 if (process_connect(transport, for_push)) {
878 do_take_over(transport);
879 return transport->get_refs_list(transport, for_push);
882 if (data->push && for_push)
883 write_str_in_full(helper->in, "list for-push\n");
884 else
885 write_str_in_full(helper->in, "list\n");
887 while (1) {
888 char *eov, *eon;
889 recvline(data, &buf);
891 if (!*buf.buf)
892 break;
894 eov = strchr(buf.buf, ' ');
895 if (!eov)
896 die("Malformed response in ref list: %s", buf.buf);
897 eon = strchr(eov + 1, ' ');
898 *eov = '\0';
899 if (eon)
900 *eon = '\0';
901 *tail = alloc_ref(eov + 1);
902 if (buf.buf[0] == '@')
903 (*tail)->symref = xstrdup(buf.buf + 1);
904 else if (buf.buf[0] != '?')
905 get_sha1_hex(buf.buf, (*tail)->old_sha1);
906 if (eon) {
907 if (has_attribute(eon + 1, "unchanged")) {
908 (*tail)->status |= REF_STATUS_UPTODATE;
909 read_ref((*tail)->name, (*tail)->old_sha1);
912 tail = &((*tail)->next);
914 if (debug)
915 fprintf(stderr, "Debug: Read ref listing.\n");
916 strbuf_release(&buf);
918 for (posn = ret; posn; posn = posn->next)
919 resolve_remote_symref(posn, ret);
921 return ret;
924 int transport_helper_init(struct transport *transport, const char *name)
926 struct helper_data *data = xcalloc(sizeof(*data), 1);
927 data->name = name;
929 if (getenv("GIT_TRANSPORT_HELPER_DEBUG"))
930 debug = 1;
932 transport->data = data;
933 transport->set_option = set_helper_option;
934 transport->get_refs_list = get_refs_list;
935 transport->fetch = fetch;
936 transport->push_refs = push_refs;
937 transport->disconnect = release_helper;
938 transport->connect = connect_helper;
939 transport->smart_options = &(data->transport_options);
940 return 0;
944 * Linux pipes can buffer 65536 bytes at once (and most platforms can
945 * buffer less), so attempt reads and writes with up to that size.
947 #define BUFFERSIZE 65536
948 /* This should be enough to hold debugging message. */
949 #define PBUFFERSIZE 8192
951 /* Print bidirectional transfer loop debug message. */
952 static void transfer_debug(const char *fmt, ...)
954 va_list args;
955 char msgbuf[PBUFFERSIZE];
956 static int debug_enabled = -1;
958 if (debug_enabled < 0)
959 debug_enabled = getenv("GIT_TRANSLOOP_DEBUG") ? 1 : 0;
960 if (!debug_enabled)
961 return;
963 va_start(args, fmt);
964 vsnprintf(msgbuf, PBUFFERSIZE, fmt, args);
965 va_end(args);
966 fprintf(stderr, "Transfer loop debugging: %s\n", msgbuf);
969 /* Stream state: More data may be coming in this direction. */
970 #define SSTATE_TRANSFERING 0
972 * Stream state: No more data coming in this direction, flushing rest of
973 * data.
975 #define SSTATE_FLUSHING 1
976 /* Stream state: Transfer in this direction finished. */
977 #define SSTATE_FINISHED 2
979 #define STATE_NEEDS_READING(state) ((state) <= SSTATE_TRANSFERING)
980 #define STATE_NEEDS_WRITING(state) ((state) <= SSTATE_FLUSHING)
981 #define STATE_NEEDS_CLOSING(state) ((state) == SSTATE_FLUSHING)
983 /* Unidirectional transfer. */
984 struct unidirectional_transfer {
985 /* Source */
986 int src;
987 /* Destination */
988 int dest;
989 /* Is source socket? */
990 int src_is_sock;
991 /* Is destination socket? */
992 int dest_is_sock;
993 /* Transfer state (TRANSFERRING/FLUSHING/FINISHED) */
994 int state;
995 /* Buffer. */
996 char buf[BUFFERSIZE];
997 /* Buffer used. */
998 size_t bufuse;
999 /* Name of source. */
1000 const char *src_name;
1001 /* Name of destination. */
1002 const char *dest_name;
1005 /* Closes the target (for writing) if transfer has finished. */
1006 static void udt_close_if_finished(struct unidirectional_transfer *t)
1008 if (STATE_NEEDS_CLOSING(t->state) && !t->bufuse) {
1009 t->state = SSTATE_FINISHED;
1010 if (t->dest_is_sock)
1011 shutdown(t->dest, SHUT_WR);
1012 else
1013 close(t->dest);
1014 transfer_debug("Closed %s.", t->dest_name);
1019 * Tries to read read data from source into buffer. If buffer is full,
1020 * no data is read. Returns 0 on success, -1 on error.
1022 static int udt_do_read(struct unidirectional_transfer *t)
1024 ssize_t bytes;
1026 if (t->bufuse == BUFFERSIZE)
1027 return 0; /* No space for more. */
1029 transfer_debug("%s is readable", t->src_name);
1030 bytes = read(t->src, t->buf + t->bufuse, BUFFERSIZE - t->bufuse);
1031 if (bytes < 0 && errno != EWOULDBLOCK && errno != EAGAIN &&
1032 errno != EINTR) {
1033 error("read(%s) failed: %s", t->src_name, strerror(errno));
1034 return -1;
1035 } else if (bytes == 0) {
1036 transfer_debug("%s EOF (with %i bytes in buffer)",
1037 t->src_name, t->bufuse);
1038 t->state = SSTATE_FLUSHING;
1039 } else if (bytes > 0) {
1040 t->bufuse += bytes;
1041 transfer_debug("Read %i bytes from %s (buffer now at %i)",
1042 (int)bytes, t->src_name, (int)t->bufuse);
1044 return 0;
1047 /* Tries to write data from buffer into destination. If buffer is empty,
1048 * no data is written. Returns 0 on success, -1 on error.
1050 static int udt_do_write(struct unidirectional_transfer *t)
1052 ssize_t bytes;
1054 if (t->bufuse == 0)
1055 return 0; /* Nothing to write. */
1057 transfer_debug("%s is writable", t->dest_name);
1058 bytes = write(t->dest, t->buf, t->bufuse);
1059 if (bytes < 0 && errno != EWOULDBLOCK && errno != EAGAIN &&
1060 errno != EINTR) {
1061 error("write(%s) failed: %s", t->dest_name, strerror(errno));
1062 return -1;
1063 } else if (bytes > 0) {
1064 t->bufuse -= bytes;
1065 if (t->bufuse)
1066 memmove(t->buf, t->buf + bytes, t->bufuse);
1067 transfer_debug("Wrote %i bytes to %s (buffer now at %i)",
1068 (int)bytes, t->dest_name, (int)t->bufuse);
1070 return 0;
1074 /* State of bidirectional transfer loop. */
1075 struct bidirectional_transfer_state {
1076 /* Direction from program to git. */
1077 struct unidirectional_transfer ptg;
1078 /* Direction from git to program. */
1079 struct unidirectional_transfer gtp;
1082 static void *udt_copy_task_routine(void *udt)
1084 struct unidirectional_transfer *t = (struct unidirectional_transfer *)udt;
1085 while (t->state != SSTATE_FINISHED) {
1086 if (STATE_NEEDS_READING(t->state))
1087 if (udt_do_read(t))
1088 return NULL;
1089 if (STATE_NEEDS_WRITING(t->state))
1090 if (udt_do_write(t))
1091 return NULL;
1092 if (STATE_NEEDS_CLOSING(t->state))
1093 udt_close_if_finished(t);
1095 return udt; /* Just some non-NULL value. */
1098 #ifndef NO_PTHREADS
1101 * Join thread, with apporiate errors on failure. Name is name for the
1102 * thread (for error messages). Returns 0 on success, 1 on failure.
1104 static int tloop_join(pthread_t thread, const char *name)
1106 int err;
1107 void *tret;
1108 err = pthread_join(thread, &tret);
1109 if (!tret) {
1110 error("%s thread failed", name);
1111 return 1;
1113 if (err) {
1114 error("%s thread failed to join: %s", name, strerror(err));
1115 return 1;
1117 return 0;
1121 * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1122 * -1 on failure.
1124 static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1126 pthread_t gtp_thread;
1127 pthread_t ptg_thread;
1128 int err;
1129 int ret = 0;
1130 err = pthread_create(&gtp_thread, NULL, udt_copy_task_routine,
1131 &s->gtp);
1132 if (err)
1133 die("Can't start thread for copying data: %s", strerror(err));
1134 err = pthread_create(&ptg_thread, NULL, udt_copy_task_routine,
1135 &s->ptg);
1136 if (err)
1137 die("Can't start thread for copying data: %s", strerror(err));
1139 ret |= tloop_join(gtp_thread, "Git to program copy");
1140 ret |= tloop_join(ptg_thread, "Program to git copy");
1141 return ret;
1143 #else
1145 /* Close the source and target (for writing) for transfer. */
1146 static void udt_kill_transfer(struct unidirectional_transfer *t)
1148 t->state = SSTATE_FINISHED;
1150 * Socket read end left open isn't a disaster if nobody
1151 * attempts to read from it (mingw compat headers do not
1152 * have SHUT_RD)...
1154 * We can't fully close the socket since otherwise gtp
1155 * task would first close the socket it sends data to
1156 * while closing the ptg file descriptors.
1158 if (!t->src_is_sock)
1159 close(t->src);
1160 if (t->dest_is_sock)
1161 shutdown(t->dest, SHUT_WR);
1162 else
1163 close(t->dest);
1167 * Join process, with apporiate errors on failure. Name is name for the
1168 * process (for error messages). Returns 0 on success, 1 on failure.
1170 static int tloop_join(pid_t pid, const char *name)
1172 int tret;
1173 if (waitpid(pid, &tret, 0) < 0) {
1174 error("%s process failed to wait: %s", name, strerror(errno));
1175 return 1;
1177 if (!WIFEXITED(tret) || WEXITSTATUS(tret)) {
1178 error("%s process failed", name);
1179 return 1;
1181 return 0;
1185 * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1186 * -1 on failure.
1188 static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1190 pid_t pid1, pid2;
1191 int ret = 0;
1193 /* Fork thread #1: git to program. */
1194 pid1 = fork();
1195 if (pid1 < 0)
1196 die_errno("Can't start thread for copying data");
1197 else if (pid1 == 0) {
1198 udt_kill_transfer(&s->ptg);
1199 exit(udt_copy_task_routine(&s->gtp) ? 0 : 1);
1202 /* Fork thread #2: program to git. */
1203 pid2 = fork();
1204 if (pid2 < 0)
1205 die_errno("Can't start thread for copying data");
1206 else if (pid2 == 0) {
1207 udt_kill_transfer(&s->gtp);
1208 exit(udt_copy_task_routine(&s->ptg) ? 0 : 1);
1212 * Close both streams in parent as to not interfere with
1213 * end of file detection and wait for both tasks to finish.
1215 udt_kill_transfer(&s->gtp);
1216 udt_kill_transfer(&s->ptg);
1217 ret |= tloop_join(pid1, "Git to program copy");
1218 ret |= tloop_join(pid2, "Program to git copy");
1219 return ret;
1221 #endif
1224 * Copies data from stdin to output and from input to stdout simultaneously.
1225 * Additionally filtering through given filter. If filter is NULL, uses
1226 * identity filter.
1228 int bidirectional_transfer_loop(int input, int output)
1230 struct bidirectional_transfer_state state;
1232 /* Fill the state fields. */
1233 state.ptg.src = input;
1234 state.ptg.dest = 1;
1235 state.ptg.src_is_sock = (input == output);
1236 state.ptg.dest_is_sock = 0;
1237 state.ptg.state = SSTATE_TRANSFERING;
1238 state.ptg.bufuse = 0;
1239 state.ptg.src_name = "remote input";
1240 state.ptg.dest_name = "stdout";
1242 state.gtp.src = 0;
1243 state.gtp.dest = output;
1244 state.gtp.src_is_sock = 0;
1245 state.gtp.dest_is_sock = (input == output);
1246 state.gtp.state = SSTATE_TRANSFERING;
1247 state.gtp.bufuse = 0;
1248 state.gtp.src_name = "stdin";
1249 state.gtp.dest_name = "remote output";
1251 return tloop_spawnwait_tasks(&state);