update-index: add fsmonitor support to update-index
[alt-git.git] / transport-helper.c
blobf50b34df2dba4827db6a96cf97d1c4ac7ca811a0
1 #include "cache.h"
2 #include "transport.h"
3 #include "quote.h"
4 #include "run-command.h"
5 #include "commit.h"
6 #include "diff.h"
7 #include "revision.h"
8 #include "remote.h"
9 #include "string-list.h"
10 #include "thread-utils.h"
11 #include "sigchain.h"
12 #include "argv-array.h"
13 #include "refs.h"
15 static int debug;
17 struct helper_data {
18 const char *name;
19 struct child_process *helper;
20 FILE *out;
21 unsigned fetch : 1,
22 import : 1,
23 bidi_import : 1,
24 export : 1,
25 option : 1,
26 push : 1,
27 connect : 1,
28 signed_tags : 1,
29 check_connectivity : 1,
30 no_disconnect_req : 1,
31 no_private_update : 1;
32 char *export_marks;
33 char *import_marks;
34 /* These go from remote name (as in "list") to private name */
35 struct refspec *refspecs;
36 int refspec_nr;
37 /* Transport options for fetch-pack/send-pack (should one of
38 * those be invoked).
40 struct git_transport_options transport_options;
43 static void sendline(struct helper_data *helper, struct strbuf *buffer)
45 if (debug)
46 fprintf(stderr, "Debug: Remote helper: -> %s", buffer->buf);
47 if (write_in_full(helper->helper->in, buffer->buf, buffer->len)
48 != buffer->len)
49 die_errno("Full write to remote helper failed");
52 static int recvline_fh(FILE *helper, struct strbuf *buffer, const char *name)
54 strbuf_reset(buffer);
55 if (debug)
56 fprintf(stderr, "Debug: Remote helper: Waiting...\n");
57 if (strbuf_getline(buffer, helper) == EOF) {
58 if (debug)
59 fprintf(stderr, "Debug: Remote helper quit.\n");
60 return 1;
63 if (debug)
64 fprintf(stderr, "Debug: Remote helper: <- %s\n", buffer->buf);
65 return 0;
68 static int recvline(struct helper_data *helper, struct strbuf *buffer)
70 return recvline_fh(helper->out, buffer, helper->name);
73 static void write_constant(int fd, const char *str)
75 if (debug)
76 fprintf(stderr, "Debug: Remote helper: -> %s", str);
77 if (write_in_full(fd, str, strlen(str)) != strlen(str))
78 die_errno("Full write to remote helper failed");
81 static const char *remove_ext_force(const char *url)
83 if (url) {
84 const char *colon = strchr(url, ':');
85 if (colon && colon[1] == ':')
86 return colon + 2;
88 return url;
91 static void do_take_over(struct transport *transport)
93 struct helper_data *data;
94 data = (struct helper_data *)transport->data;
95 transport_take_over(transport, data->helper);
96 fclose(data->out);
97 free(data);
100 static void standard_options(struct transport *t);
102 static struct child_process *get_helper(struct transport *transport)
104 struct helper_data *data = transport->data;
105 struct strbuf buf = STRBUF_INIT;
106 struct child_process *helper;
107 const char **refspecs = NULL;
108 int refspec_nr = 0;
109 int refspec_alloc = 0;
110 int duped;
111 int code;
113 if (data->helper)
114 return data->helper;
116 helper = xmalloc(sizeof(*helper));
117 child_process_init(helper);
118 helper->in = -1;
119 helper->out = -1;
120 helper->err = 0;
121 argv_array_pushf(&helper->args, "git-remote-%s", data->name);
122 argv_array_push(&helper->args, transport->remote->name);
123 argv_array_push(&helper->args, remove_ext_force(transport->url));
124 helper->git_cmd = 0;
125 helper->silent_exec_failure = 1;
127 if (have_git_dir())
128 argv_array_pushf(&helper->env_array, "%s=%s",
129 GIT_DIR_ENVIRONMENT, get_git_dir());
131 code = start_command(helper);
132 if (code < 0 && errno == ENOENT)
133 die("Unable to find remote helper for '%s'", data->name);
134 else if (code != 0)
135 exit(code);
137 data->helper = helper;
138 data->no_disconnect_req = 0;
141 * Open the output as FILE* so strbuf_getline_*() family of
142 * functions can be used.
143 * Do this with duped fd because fclose() will close the fd,
144 * and stuff like taking over will require the fd to remain.
146 duped = dup(helper->out);
147 if (duped < 0)
148 die_errno("Can't dup helper output fd");
149 data->out = xfdopen(duped, "r");
151 write_constant(helper->in, "capabilities\n");
153 while (1) {
154 const char *capname, *arg;
155 int mandatory = 0;
156 if (recvline(data, &buf))
157 exit(128);
159 if (!*buf.buf)
160 break;
162 if (*buf.buf == '*') {
163 capname = buf.buf + 1;
164 mandatory = 1;
165 } else
166 capname = buf.buf;
168 if (debug)
169 fprintf(stderr, "Debug: Got cap %s\n", capname);
170 if (!strcmp(capname, "fetch"))
171 data->fetch = 1;
172 else if (!strcmp(capname, "option"))
173 data->option = 1;
174 else if (!strcmp(capname, "push"))
175 data->push = 1;
176 else if (!strcmp(capname, "import"))
177 data->import = 1;
178 else if (!strcmp(capname, "bidi-import"))
179 data->bidi_import = 1;
180 else if (!strcmp(capname, "export"))
181 data->export = 1;
182 else if (!strcmp(capname, "check-connectivity"))
183 data->check_connectivity = 1;
184 else if (!data->refspecs && skip_prefix(capname, "refspec ", &arg)) {
185 ALLOC_GROW(refspecs,
186 refspec_nr + 1,
187 refspec_alloc);
188 refspecs[refspec_nr++] = xstrdup(arg);
189 } else if (!strcmp(capname, "connect")) {
190 data->connect = 1;
191 } else if (!strcmp(capname, "signed-tags")) {
192 data->signed_tags = 1;
193 } else if (skip_prefix(capname, "export-marks ", &arg)) {
194 data->export_marks = xstrdup(arg);
195 } else if (skip_prefix(capname, "import-marks ", &arg)) {
196 data->import_marks = xstrdup(arg);
197 } else if (starts_with(capname, "no-private-update")) {
198 data->no_private_update = 1;
199 } else if (mandatory) {
200 die("Unknown mandatory capability %s. This remote "
201 "helper probably needs newer version of Git.",
202 capname);
205 if (refspecs) {
206 int i;
207 data->refspec_nr = refspec_nr;
208 data->refspecs = parse_fetch_refspec(refspec_nr, refspecs);
209 for (i = 0; i < refspec_nr; i++)
210 free((char *)refspecs[i]);
211 free(refspecs);
212 } else if (data->import || data->bidi_import || data->export) {
213 warning("This remote helper should implement refspec capability.");
215 strbuf_release(&buf);
216 if (debug)
217 fprintf(stderr, "Debug: Capabilities complete.\n");
218 standard_options(transport);
219 return data->helper;
222 static int disconnect_helper(struct transport *transport)
224 struct helper_data *data = transport->data;
225 int res = 0;
227 if (data->helper) {
228 if (debug)
229 fprintf(stderr, "Debug: Disconnecting.\n");
230 if (!data->no_disconnect_req) {
232 * Ignore write errors; there's nothing we can do,
233 * since we're about to close the pipe anyway. And the
234 * most likely error is EPIPE due to the helper dying
235 * to report an error itself.
237 sigchain_push(SIGPIPE, SIG_IGN);
238 xwrite(data->helper->in, "\n", 1);
239 sigchain_pop(SIGPIPE);
241 close(data->helper->in);
242 close(data->helper->out);
243 fclose(data->out);
244 res = finish_command(data->helper);
245 FREE_AND_NULL(data->helper);
247 return res;
250 static const char *unsupported_options[] = {
251 TRANS_OPT_UPLOADPACK,
252 TRANS_OPT_RECEIVEPACK,
253 TRANS_OPT_THIN,
254 TRANS_OPT_KEEP
257 static const char *boolean_options[] = {
258 TRANS_OPT_THIN,
259 TRANS_OPT_KEEP,
260 TRANS_OPT_FOLLOWTAGS,
261 TRANS_OPT_DEEPEN_RELATIVE
264 static int strbuf_set_helper_option(struct helper_data *data,
265 struct strbuf *buf)
267 int ret;
269 sendline(data, buf);
270 if (recvline(data, buf))
271 exit(128);
273 if (!strcmp(buf->buf, "ok"))
274 ret = 0;
275 else if (starts_with(buf->buf, "error"))
276 ret = -1;
277 else if (!strcmp(buf->buf, "unsupported"))
278 ret = 1;
279 else {
280 warning("%s unexpectedly said: '%s'", data->name, buf->buf);
281 ret = 1;
283 return ret;
286 static int string_list_set_helper_option(struct helper_data *data,
287 const char *name,
288 struct string_list *list)
290 struct strbuf buf = STRBUF_INIT;
291 int i, ret = 0;
293 for (i = 0; i < list->nr; i++) {
294 strbuf_addf(&buf, "option %s ", name);
295 quote_c_style(list->items[i].string, &buf, NULL, 0);
296 strbuf_addch(&buf, '\n');
298 if ((ret = strbuf_set_helper_option(data, &buf)))
299 break;
300 strbuf_reset(&buf);
302 strbuf_release(&buf);
303 return ret;
306 static int set_helper_option(struct transport *transport,
307 const char *name, const char *value)
309 struct helper_data *data = transport->data;
310 struct strbuf buf = STRBUF_INIT;
311 int i, ret, is_bool = 0;
313 get_helper(transport);
315 if (!data->option)
316 return 1;
318 if (!strcmp(name, "deepen-not"))
319 return string_list_set_helper_option(data, name,
320 (struct string_list *)value);
322 for (i = 0; i < ARRAY_SIZE(unsupported_options); i++) {
323 if (!strcmp(name, unsupported_options[i]))
324 return 1;
327 for (i = 0; i < ARRAY_SIZE(boolean_options); i++) {
328 if (!strcmp(name, boolean_options[i])) {
329 is_bool = 1;
330 break;
334 strbuf_addf(&buf, "option %s ", name);
335 if (is_bool)
336 strbuf_addstr(&buf, value ? "true" : "false");
337 else
338 quote_c_style(value, &buf, NULL, 0);
339 strbuf_addch(&buf, '\n');
341 ret = strbuf_set_helper_option(data, &buf);
342 strbuf_release(&buf);
343 return ret;
346 static void standard_options(struct transport *t)
348 char buf[16];
349 int v = t->verbose;
351 set_helper_option(t, "progress", t->progress ? "true" : "false");
353 xsnprintf(buf, sizeof(buf), "%d", v + 1);
354 set_helper_option(t, "verbosity", buf);
356 switch (t->family) {
357 case TRANSPORT_FAMILY_ALL:
359 * this is already the default,
360 * do not break old remote helpers by setting "all" here
362 break;
363 case TRANSPORT_FAMILY_IPV4:
364 set_helper_option(t, "family", "ipv4");
365 break;
366 case TRANSPORT_FAMILY_IPV6:
367 set_helper_option(t, "family", "ipv6");
368 break;
372 static int release_helper(struct transport *transport)
374 int res = 0;
375 struct helper_data *data = transport->data;
376 free_refspec(data->refspec_nr, data->refspecs);
377 data->refspecs = NULL;
378 res = disconnect_helper(transport);
379 free(transport->data);
380 return res;
383 static int fetch_with_fetch(struct transport *transport,
384 int nr_heads, struct ref **to_fetch)
386 struct helper_data *data = transport->data;
387 int i;
388 struct strbuf buf = STRBUF_INIT;
390 for (i = 0; i < nr_heads; i++) {
391 const struct ref *posn = to_fetch[i];
392 if (posn->status & REF_STATUS_UPTODATE)
393 continue;
395 strbuf_addf(&buf, "fetch %s %s\n",
396 oid_to_hex(&posn->old_oid),
397 posn->symref ? posn->symref : posn->name);
400 strbuf_addch(&buf, '\n');
401 sendline(data, &buf);
403 while (1) {
404 if (recvline(data, &buf))
405 exit(128);
407 if (starts_with(buf.buf, "lock ")) {
408 const char *name = buf.buf + 5;
409 if (transport->pack_lockfile)
410 warning("%s also locked %s", data->name, name);
411 else
412 transport->pack_lockfile = xstrdup(name);
414 else if (data->check_connectivity &&
415 data->transport_options.check_self_contained_and_connected &&
416 !strcmp(buf.buf, "connectivity-ok"))
417 data->transport_options.self_contained_and_connected = 1;
418 else if (!buf.len)
419 break;
420 else
421 warning("%s unexpectedly said: '%s'", data->name, buf.buf);
423 strbuf_release(&buf);
424 return 0;
427 static int get_importer(struct transport *transport, struct child_process *fastimport)
429 struct child_process *helper = get_helper(transport);
430 struct helper_data *data = transport->data;
431 int cat_blob_fd, code;
432 child_process_init(fastimport);
433 fastimport->in = helper->out;
434 argv_array_push(&fastimport->args, "fast-import");
435 argv_array_push(&fastimport->args, debug ? "--stats" : "--quiet");
437 if (data->bidi_import) {
438 cat_blob_fd = xdup(helper->in);
439 argv_array_pushf(&fastimport->args, "--cat-blob-fd=%d", cat_blob_fd);
441 fastimport->git_cmd = 1;
443 code = start_command(fastimport);
444 return code;
447 static int get_exporter(struct transport *transport,
448 struct child_process *fastexport,
449 struct string_list *revlist_args)
451 struct helper_data *data = transport->data;
452 struct child_process *helper = get_helper(transport);
453 int i;
455 child_process_init(fastexport);
457 /* we need to duplicate helper->in because we want to use it after
458 * fastexport is done with it. */
459 fastexport->out = dup(helper->in);
460 argv_array_push(&fastexport->args, "fast-export");
461 argv_array_push(&fastexport->args, "--use-done-feature");
462 argv_array_push(&fastexport->args, data->signed_tags ?
463 "--signed-tags=verbatim" : "--signed-tags=warn-strip");
464 if (data->export_marks)
465 argv_array_pushf(&fastexport->args, "--export-marks=%s.tmp", data->export_marks);
466 if (data->import_marks)
467 argv_array_pushf(&fastexport->args, "--import-marks=%s", data->import_marks);
469 for (i = 0; i < revlist_args->nr; i++)
470 argv_array_push(&fastexport->args, revlist_args->items[i].string);
472 fastexport->git_cmd = 1;
473 return start_command(fastexport);
476 static int fetch_with_import(struct transport *transport,
477 int nr_heads, struct ref **to_fetch)
479 struct child_process fastimport;
480 struct helper_data *data = transport->data;
481 int i;
482 struct ref *posn;
483 struct strbuf buf = STRBUF_INIT;
485 get_helper(transport);
487 if (get_importer(transport, &fastimport))
488 die("Couldn't run fast-import");
490 for (i = 0; i < nr_heads; i++) {
491 posn = to_fetch[i];
492 if (posn->status & REF_STATUS_UPTODATE)
493 continue;
495 strbuf_addf(&buf, "import %s\n",
496 posn->symref ? posn->symref : posn->name);
497 sendline(data, &buf);
498 strbuf_reset(&buf);
501 write_constant(data->helper->in, "\n");
503 * remote-helpers that advertise the bidi-import capability are required to
504 * buffer the complete batch of import commands until this newline before
505 * sending data to fast-import.
506 * These helpers read back data from fast-import on their stdin, which could
507 * be mixed with import commands, otherwise.
510 if (finish_command(&fastimport))
511 die("Error while running fast-import");
514 * The fast-import stream of a remote helper that advertises
515 * the "refspec" capability writes to the refs named after the
516 * right hand side of the first refspec matching each ref we
517 * were fetching.
519 * (If no "refspec" capability was specified, for historical
520 * reasons we default to the equivalent of *:*.)
522 * Store the result in to_fetch[i].old_sha1. Callers such
523 * as "git fetch" can use the value to write feedback to the
524 * terminal, populate FETCH_HEAD, and determine what new value
525 * should be written to peer_ref if the update is a
526 * fast-forward or this is a forced update.
528 for (i = 0; i < nr_heads; i++) {
529 char *private, *name;
530 posn = to_fetch[i];
531 if (posn->status & REF_STATUS_UPTODATE)
532 continue;
533 name = posn->symref ? posn->symref : posn->name;
534 if (data->refspecs)
535 private = apply_refspecs(data->refspecs, data->refspec_nr, name);
536 else
537 private = xstrdup(name);
538 if (private) {
539 if (read_ref(private, posn->old_oid.hash) < 0)
540 die("Could not read ref %s", private);
541 free(private);
544 strbuf_release(&buf);
545 return 0;
548 static int process_connect_service(struct transport *transport,
549 const char *name, const char *exec)
551 struct helper_data *data = transport->data;
552 struct strbuf cmdbuf = STRBUF_INIT;
553 struct child_process *helper;
554 int r, duped, ret = 0;
555 FILE *input;
557 helper = get_helper(transport);
560 * Yes, dup the pipe another time, as we need unbuffered version
561 * of input pipe as FILE*. fclose() closes the underlying fd and
562 * stream buffering only can be changed before first I/O operation
563 * on it.
565 duped = dup(helper->out);
566 if (duped < 0)
567 die_errno("Can't dup helper output fd");
568 input = xfdopen(duped, "r");
569 setvbuf(input, NULL, _IONBF, 0);
572 * Handle --upload-pack and friends. This is fire and forget...
573 * just warn if it fails.
575 if (strcmp(name, exec)) {
576 r = set_helper_option(transport, "servpath", exec);
577 if (r > 0)
578 warning("Setting remote service path not supported by protocol.");
579 else if (r < 0)
580 warning("Invalid remote service path.");
583 if (data->connect)
584 strbuf_addf(&cmdbuf, "connect %s\n", name);
585 else
586 goto exit;
588 sendline(data, &cmdbuf);
589 if (recvline_fh(input, &cmdbuf, name))
590 exit(128);
592 if (!strcmp(cmdbuf.buf, "")) {
593 data->no_disconnect_req = 1;
594 if (debug)
595 fprintf(stderr, "Debug: Smart transport connection "
596 "ready.\n");
597 ret = 1;
598 } else if (!strcmp(cmdbuf.buf, "fallback")) {
599 if (debug)
600 fprintf(stderr, "Debug: Falling back to dumb "
601 "transport.\n");
602 } else
603 die("Unknown response to connect: %s",
604 cmdbuf.buf);
606 exit:
607 fclose(input);
608 return ret;
611 static int process_connect(struct transport *transport,
612 int for_push)
614 struct helper_data *data = transport->data;
615 const char *name;
616 const char *exec;
618 name = for_push ? "git-receive-pack" : "git-upload-pack";
619 if (for_push)
620 exec = data->transport_options.receivepack;
621 else
622 exec = data->transport_options.uploadpack;
624 return process_connect_service(transport, name, exec);
627 static int connect_helper(struct transport *transport, const char *name,
628 const char *exec, int fd[2])
630 struct helper_data *data = transport->data;
632 /* Get_helper so connect is inited. */
633 get_helper(transport);
634 if (!data->connect)
635 die("Operation not supported by protocol.");
637 if (!process_connect_service(transport, name, exec))
638 die("Can't connect to subservice %s.", name);
640 fd[0] = data->helper->out;
641 fd[1] = data->helper->in;
642 return 0;
645 static int fetch(struct transport *transport,
646 int nr_heads, struct ref **to_fetch)
648 struct helper_data *data = transport->data;
649 int i, count;
651 if (process_connect(transport, 0)) {
652 do_take_over(transport);
653 return transport->fetch(transport, nr_heads, to_fetch);
656 count = 0;
657 for (i = 0; i < nr_heads; i++)
658 if (!(to_fetch[i]->status & REF_STATUS_UPTODATE))
659 count++;
661 if (!count)
662 return 0;
664 if (data->check_connectivity &&
665 data->transport_options.check_self_contained_and_connected)
666 set_helper_option(transport, "check-connectivity", "true");
668 if (transport->cloning)
669 set_helper_option(transport, "cloning", "true");
671 if (data->transport_options.update_shallow)
672 set_helper_option(transport, "update-shallow", "true");
674 if (data->fetch)
675 return fetch_with_fetch(transport, nr_heads, to_fetch);
677 if (data->import)
678 return fetch_with_import(transport, nr_heads, to_fetch);
680 return -1;
683 static int push_update_ref_status(struct strbuf *buf,
684 struct ref **ref,
685 struct ref *remote_refs)
687 char *refname, *msg;
688 int status, forced = 0;
690 if (starts_with(buf->buf, "ok ")) {
691 status = REF_STATUS_OK;
692 refname = buf->buf + 3;
693 } else if (starts_with(buf->buf, "error ")) {
694 status = REF_STATUS_REMOTE_REJECT;
695 refname = buf->buf + 6;
696 } else
697 die("expected ok/error, helper said '%s'", buf->buf);
699 msg = strchr(refname, ' ');
700 if (msg) {
701 struct strbuf msg_buf = STRBUF_INIT;
702 const char *end;
704 *msg++ = '\0';
705 if (!unquote_c_style(&msg_buf, msg, &end))
706 msg = strbuf_detach(&msg_buf, NULL);
707 else
708 msg = xstrdup(msg);
709 strbuf_release(&msg_buf);
711 if (!strcmp(msg, "no match")) {
712 status = REF_STATUS_NONE;
713 FREE_AND_NULL(msg);
715 else if (!strcmp(msg, "up to date")) {
716 status = REF_STATUS_UPTODATE;
717 FREE_AND_NULL(msg);
719 else if (!strcmp(msg, "non-fast forward")) {
720 status = REF_STATUS_REJECT_NONFASTFORWARD;
721 FREE_AND_NULL(msg);
723 else if (!strcmp(msg, "already exists")) {
724 status = REF_STATUS_REJECT_ALREADY_EXISTS;
725 FREE_AND_NULL(msg);
727 else if (!strcmp(msg, "fetch first")) {
728 status = REF_STATUS_REJECT_FETCH_FIRST;
729 FREE_AND_NULL(msg);
731 else if (!strcmp(msg, "needs force")) {
732 status = REF_STATUS_REJECT_NEEDS_FORCE;
733 FREE_AND_NULL(msg);
735 else if (!strcmp(msg, "stale info")) {
736 status = REF_STATUS_REJECT_STALE;
737 FREE_AND_NULL(msg);
739 else if (!strcmp(msg, "forced update")) {
740 forced = 1;
741 FREE_AND_NULL(msg);
745 if (*ref)
746 *ref = find_ref_by_name(*ref, refname);
747 if (!*ref)
748 *ref = find_ref_by_name(remote_refs, refname);
749 if (!*ref) {
750 warning("helper reported unexpected status of %s", refname);
751 return 1;
754 if ((*ref)->status != REF_STATUS_NONE) {
756 * Earlier, the ref was marked not to be pushed, so ignore the ref
757 * status reported by the remote helper if the latter is 'no match'.
759 if (status == REF_STATUS_NONE)
760 return 1;
763 (*ref)->status = status;
764 (*ref)->forced_update |= forced;
765 (*ref)->remote_status = msg;
766 return !(status == REF_STATUS_OK);
769 static int push_update_refs_status(struct helper_data *data,
770 struct ref *remote_refs,
771 int flags)
773 struct strbuf buf = STRBUF_INIT;
774 struct ref *ref = remote_refs;
775 int ret = 0;
777 for (;;) {
778 char *private;
780 if (recvline(data, &buf)) {
781 ret = 1;
782 break;
785 if (!buf.len)
786 break;
788 if (push_update_ref_status(&buf, &ref, remote_refs))
789 continue;
791 if (flags & TRANSPORT_PUSH_DRY_RUN || !data->refspecs || data->no_private_update)
792 continue;
794 /* propagate back the update to the remote namespace */
795 private = apply_refspecs(data->refspecs, data->refspec_nr, ref->name);
796 if (!private)
797 continue;
798 update_ref("update by helper", private, ref->new_oid.hash, NULL, 0, 0);
799 free(private);
801 strbuf_release(&buf);
802 return ret;
805 static void set_common_push_options(struct transport *transport,
806 const char *name, int flags)
808 if (flags & TRANSPORT_PUSH_DRY_RUN) {
809 if (set_helper_option(transport, "dry-run", "true") != 0)
810 die("helper %s does not support dry-run", name);
811 } else if (flags & TRANSPORT_PUSH_CERT_ALWAYS) {
812 if (set_helper_option(transport, TRANS_OPT_PUSH_CERT, "true") != 0)
813 die("helper %s does not support --signed", name);
814 } else if (flags & TRANSPORT_PUSH_CERT_IF_ASKED) {
815 if (set_helper_option(transport, TRANS_OPT_PUSH_CERT, "if-asked") != 0)
816 die("helper %s does not support --signed=if-asked", name);
819 if (flags & TRANSPORT_PUSH_OPTIONS) {
820 struct string_list_item *item;
821 for_each_string_list_item(item, transport->push_options)
822 if (set_helper_option(transport, "push-option", item->string) != 0)
823 die("helper %s does not support 'push-option'", name);
827 static int push_refs_with_push(struct transport *transport,
828 struct ref *remote_refs, int flags)
830 int force_all = flags & TRANSPORT_PUSH_FORCE;
831 int mirror = flags & TRANSPORT_PUSH_MIRROR;
832 struct helper_data *data = transport->data;
833 struct strbuf buf = STRBUF_INIT;
834 struct ref *ref;
835 struct string_list cas_options = STRING_LIST_INIT_DUP;
836 struct string_list_item *cas_option;
838 get_helper(transport);
839 if (!data->push)
840 return 1;
842 for (ref = remote_refs; ref; ref = ref->next) {
843 if (!ref->peer_ref && !mirror)
844 continue;
846 /* Check for statuses set by set_ref_status_for_push() */
847 switch (ref->status) {
848 case REF_STATUS_REJECT_NONFASTFORWARD:
849 case REF_STATUS_REJECT_STALE:
850 case REF_STATUS_REJECT_ALREADY_EXISTS:
851 case REF_STATUS_UPTODATE:
852 continue;
853 default:
854 ; /* do nothing */
857 if (force_all)
858 ref->force = 1;
860 strbuf_addstr(&buf, "push ");
861 if (!ref->deletion) {
862 if (ref->force)
863 strbuf_addch(&buf, '+');
864 if (ref->peer_ref)
865 strbuf_addstr(&buf, ref->peer_ref->name);
866 else
867 strbuf_addstr(&buf, oid_to_hex(&ref->new_oid));
869 strbuf_addch(&buf, ':');
870 strbuf_addstr(&buf, ref->name);
871 strbuf_addch(&buf, '\n');
874 * The "--force-with-lease" options without explicit
875 * values to expect have already been expanded into
876 * the ref->old_oid_expect[] field; we can ignore
877 * transport->smart_options->cas altogether and instead
878 * can enumerate them from the refs.
880 if (ref->expect_old_sha1) {
881 struct strbuf cas = STRBUF_INIT;
882 strbuf_addf(&cas, "%s:%s",
883 ref->name, oid_to_hex(&ref->old_oid_expect));
884 string_list_append(&cas_options, strbuf_detach(&cas, NULL));
887 if (buf.len == 0) {
888 string_list_clear(&cas_options, 0);
889 return 0;
892 for_each_string_list_item(cas_option, &cas_options)
893 set_helper_option(transport, "cas", cas_option->string);
894 set_common_push_options(transport, data->name, flags);
896 strbuf_addch(&buf, '\n');
897 sendline(data, &buf);
898 strbuf_release(&buf);
900 return push_update_refs_status(data, remote_refs, flags);
903 static int push_refs_with_export(struct transport *transport,
904 struct ref *remote_refs, int flags)
906 struct ref *ref;
907 struct child_process *helper, exporter;
908 struct helper_data *data = transport->data;
909 struct string_list revlist_args = STRING_LIST_INIT_DUP;
910 struct strbuf buf = STRBUF_INIT;
912 if (!data->refspecs)
913 die("remote-helper doesn't support push; refspec needed");
915 set_common_push_options(transport, data->name, flags);
916 if (flags & TRANSPORT_PUSH_FORCE) {
917 if (set_helper_option(transport, "force", "true") != 0)
918 warning("helper %s does not support 'force'", data->name);
921 helper = get_helper(transport);
923 write_constant(helper->in, "export\n");
925 for (ref = remote_refs; ref; ref = ref->next) {
926 char *private;
927 struct object_id oid;
929 private = apply_refspecs(data->refspecs, data->refspec_nr, ref->name);
930 if (private && !get_oid(private, &oid)) {
931 strbuf_addf(&buf, "^%s", private);
932 string_list_append(&revlist_args, strbuf_detach(&buf, NULL));
933 oidcpy(&ref->old_oid, &oid);
935 free(private);
937 if (ref->peer_ref) {
938 if (strcmp(ref->name, ref->peer_ref->name)) {
939 if (!ref->deletion) {
940 const char *name;
941 int flag;
943 /* Follow symbolic refs (mainly for HEAD). */
944 name = resolve_ref_unsafe(
945 ref->peer_ref->name,
946 RESOLVE_REF_READING,
947 oid.hash, &flag);
948 if (!name || !(flag & REF_ISSYMREF))
949 name = ref->peer_ref->name;
951 strbuf_addf(&buf, "%s:%s", name, ref->name);
952 } else
953 strbuf_addf(&buf, ":%s", ref->name);
955 string_list_append(&revlist_args, "--refspec");
956 string_list_append(&revlist_args, buf.buf);
957 strbuf_release(&buf);
959 if (!ref->deletion)
960 string_list_append(&revlist_args, ref->peer_ref->name);
964 if (get_exporter(transport, &exporter, &revlist_args))
965 die("Couldn't run fast-export");
967 string_list_clear(&revlist_args, 1);
969 if (finish_command(&exporter))
970 die("Error while running fast-export");
971 if (push_update_refs_status(data, remote_refs, flags))
972 return 1;
974 if (data->export_marks) {
975 strbuf_addf(&buf, "%s.tmp", data->export_marks);
976 rename(buf.buf, data->export_marks);
977 strbuf_release(&buf);
980 return 0;
983 static int push_refs(struct transport *transport,
984 struct ref *remote_refs, int flags)
986 struct helper_data *data = transport->data;
988 if (process_connect(transport, 1)) {
989 do_take_over(transport);
990 return transport->push_refs(transport, remote_refs, flags);
993 if (!remote_refs) {
994 fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
995 "Perhaps you should specify a branch such as 'master'.\n");
996 return 0;
999 if (data->push)
1000 return push_refs_with_push(transport, remote_refs, flags);
1002 if (data->export)
1003 return push_refs_with_export(transport, remote_refs, flags);
1005 return -1;
1009 static int has_attribute(const char *attrs, const char *attr) {
1010 int len;
1011 if (!attrs)
1012 return 0;
1014 len = strlen(attr);
1015 for (;;) {
1016 const char *space = strchrnul(attrs, ' ');
1017 if (len == space - attrs && !strncmp(attrs, attr, len))
1018 return 1;
1019 if (!*space)
1020 return 0;
1021 attrs = space + 1;
1025 static struct ref *get_refs_list(struct transport *transport, int for_push)
1027 struct helper_data *data = transport->data;
1028 struct child_process *helper;
1029 struct ref *ret = NULL;
1030 struct ref **tail = &ret;
1031 struct ref *posn;
1032 struct strbuf buf = STRBUF_INIT;
1034 helper = get_helper(transport);
1036 if (process_connect(transport, for_push)) {
1037 do_take_over(transport);
1038 return transport->get_refs_list(transport, for_push);
1041 if (data->push && for_push)
1042 write_str_in_full(helper->in, "list for-push\n");
1043 else
1044 write_str_in_full(helper->in, "list\n");
1046 while (1) {
1047 char *eov, *eon;
1048 if (recvline(data, &buf))
1049 exit(128);
1051 if (!*buf.buf)
1052 break;
1054 eov = strchr(buf.buf, ' ');
1055 if (!eov)
1056 die("Malformed response in ref list: %s", buf.buf);
1057 eon = strchr(eov + 1, ' ');
1058 *eov = '\0';
1059 if (eon)
1060 *eon = '\0';
1061 *tail = alloc_ref(eov + 1);
1062 if (buf.buf[0] == '@')
1063 (*tail)->symref = xstrdup(buf.buf + 1);
1064 else if (buf.buf[0] != '?')
1065 get_oid_hex(buf.buf, &(*tail)->old_oid);
1066 if (eon) {
1067 if (has_attribute(eon + 1, "unchanged")) {
1068 (*tail)->status |= REF_STATUS_UPTODATE;
1069 if (read_ref((*tail)->name,
1070 (*tail)->old_oid.hash) < 0)
1071 die(_("Could not read ref %s"),
1072 (*tail)->name);
1075 tail = &((*tail)->next);
1077 if (debug)
1078 fprintf(stderr, "Debug: Read ref listing.\n");
1079 strbuf_release(&buf);
1081 for (posn = ret; posn; posn = posn->next)
1082 resolve_remote_symref(posn, ret);
1084 return ret;
1087 int transport_helper_init(struct transport *transport, const char *name)
1089 struct helper_data *data = xcalloc(1, sizeof(*data));
1090 data->name = name;
1092 transport_check_allowed(name);
1094 if (getenv("GIT_TRANSPORT_HELPER_DEBUG"))
1095 debug = 1;
1097 transport->data = data;
1098 transport->set_option = set_helper_option;
1099 transport->get_refs_list = get_refs_list;
1100 transport->fetch = fetch;
1101 transport->push_refs = push_refs;
1102 transport->disconnect = release_helper;
1103 transport->connect = connect_helper;
1104 transport->smart_options = &(data->transport_options);
1105 return 0;
1109 * Linux pipes can buffer 65536 bytes at once (and most platforms can
1110 * buffer less), so attempt reads and writes with up to that size.
1112 #define BUFFERSIZE 65536
1113 /* This should be enough to hold debugging message. */
1114 #define PBUFFERSIZE 8192
1116 /* Print bidirectional transfer loop debug message. */
1117 __attribute__((format (printf, 1, 2)))
1118 static void transfer_debug(const char *fmt, ...)
1121 * NEEDSWORK: This function is sometimes used from multiple threads, and
1122 * we end up using debug_enabled racily. That "should not matter" since
1123 * we always write the same value, but it's still wrong. This function
1124 * is listed in .tsan-suppressions for the time being.
1127 va_list args;
1128 char msgbuf[PBUFFERSIZE];
1129 static int debug_enabled = -1;
1131 if (debug_enabled < 0)
1132 debug_enabled = getenv("GIT_TRANSLOOP_DEBUG") ? 1 : 0;
1133 if (!debug_enabled)
1134 return;
1136 va_start(args, fmt);
1137 vsnprintf(msgbuf, PBUFFERSIZE, fmt, args);
1138 va_end(args);
1139 fprintf(stderr, "Transfer loop debugging: %s\n", msgbuf);
1142 /* Stream state: More data may be coming in this direction. */
1143 #define SSTATE_TRANSFERRING 0
1145 * Stream state: No more data coming in this direction, flushing rest of
1146 * data.
1148 #define SSTATE_FLUSHING 1
1149 /* Stream state: Transfer in this direction finished. */
1150 #define SSTATE_FINISHED 2
1152 #define STATE_NEEDS_READING(state) ((state) <= SSTATE_TRANSFERRING)
1153 #define STATE_NEEDS_WRITING(state) ((state) <= SSTATE_FLUSHING)
1154 #define STATE_NEEDS_CLOSING(state) ((state) == SSTATE_FLUSHING)
1156 /* Unidirectional transfer. */
1157 struct unidirectional_transfer {
1158 /* Source */
1159 int src;
1160 /* Destination */
1161 int dest;
1162 /* Is source socket? */
1163 int src_is_sock;
1164 /* Is destination socket? */
1165 int dest_is_sock;
1166 /* Transfer state (TRANSFERRING/FLUSHING/FINISHED) */
1167 int state;
1168 /* Buffer. */
1169 char buf[BUFFERSIZE];
1170 /* Buffer used. */
1171 size_t bufuse;
1172 /* Name of source. */
1173 const char *src_name;
1174 /* Name of destination. */
1175 const char *dest_name;
1178 /* Closes the target (for writing) if transfer has finished. */
1179 static void udt_close_if_finished(struct unidirectional_transfer *t)
1181 if (STATE_NEEDS_CLOSING(t->state) && !t->bufuse) {
1182 t->state = SSTATE_FINISHED;
1183 if (t->dest_is_sock)
1184 shutdown(t->dest, SHUT_WR);
1185 else
1186 close(t->dest);
1187 transfer_debug("Closed %s.", t->dest_name);
1192 * Tries to read data from source into buffer. If buffer is full,
1193 * no data is read. Returns 0 on success, -1 on error.
1195 static int udt_do_read(struct unidirectional_transfer *t)
1197 ssize_t bytes;
1199 if (t->bufuse == BUFFERSIZE)
1200 return 0; /* No space for more. */
1202 transfer_debug("%s is readable", t->src_name);
1203 bytes = read(t->src, t->buf + t->bufuse, BUFFERSIZE - t->bufuse);
1204 if (bytes < 0 && errno != EWOULDBLOCK && errno != EAGAIN &&
1205 errno != EINTR) {
1206 error_errno("read(%s) failed", t->src_name);
1207 return -1;
1208 } else if (bytes == 0) {
1209 transfer_debug("%s EOF (with %i bytes in buffer)",
1210 t->src_name, (int)t->bufuse);
1211 t->state = SSTATE_FLUSHING;
1212 } else if (bytes > 0) {
1213 t->bufuse += bytes;
1214 transfer_debug("Read %i bytes from %s (buffer now at %i)",
1215 (int)bytes, t->src_name, (int)t->bufuse);
1217 return 0;
1220 /* Tries to write data from buffer into destination. If buffer is empty,
1221 * no data is written. Returns 0 on success, -1 on error.
1223 static int udt_do_write(struct unidirectional_transfer *t)
1225 ssize_t bytes;
1227 if (t->bufuse == 0)
1228 return 0; /* Nothing to write. */
1230 transfer_debug("%s is writable", t->dest_name);
1231 bytes = xwrite(t->dest, t->buf, t->bufuse);
1232 if (bytes < 0 && errno != EWOULDBLOCK) {
1233 error_errno("write(%s) failed", t->dest_name);
1234 return -1;
1235 } else if (bytes > 0) {
1236 t->bufuse -= bytes;
1237 if (t->bufuse)
1238 memmove(t->buf, t->buf + bytes, t->bufuse);
1239 transfer_debug("Wrote %i bytes to %s (buffer now at %i)",
1240 (int)bytes, t->dest_name, (int)t->bufuse);
1242 return 0;
1246 /* State of bidirectional transfer loop. */
1247 struct bidirectional_transfer_state {
1248 /* Direction from program to git. */
1249 struct unidirectional_transfer ptg;
1250 /* Direction from git to program. */
1251 struct unidirectional_transfer gtp;
1254 static void *udt_copy_task_routine(void *udt)
1256 struct unidirectional_transfer *t = (struct unidirectional_transfer *)udt;
1257 while (t->state != SSTATE_FINISHED) {
1258 if (STATE_NEEDS_READING(t->state))
1259 if (udt_do_read(t))
1260 return NULL;
1261 if (STATE_NEEDS_WRITING(t->state))
1262 if (udt_do_write(t))
1263 return NULL;
1264 if (STATE_NEEDS_CLOSING(t->state))
1265 udt_close_if_finished(t);
1267 return udt; /* Just some non-NULL value. */
1270 #ifndef NO_PTHREADS
1273 * Join thread, with appropriate errors on failure. Name is name for the
1274 * thread (for error messages). Returns 0 on success, 1 on failure.
1276 static int tloop_join(pthread_t thread, const char *name)
1278 int err;
1279 void *tret;
1280 err = pthread_join(thread, &tret);
1281 if (!tret) {
1282 error("%s thread failed", name);
1283 return 1;
1285 if (err) {
1286 error("%s thread failed to join: %s", name, strerror(err));
1287 return 1;
1289 return 0;
1293 * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1294 * -1 on failure.
1296 static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1298 pthread_t gtp_thread;
1299 pthread_t ptg_thread;
1300 int err;
1301 int ret = 0;
1302 err = pthread_create(&gtp_thread, NULL, udt_copy_task_routine,
1303 &s->gtp);
1304 if (err)
1305 die("Can't start thread for copying data: %s", strerror(err));
1306 err = pthread_create(&ptg_thread, NULL, udt_copy_task_routine,
1307 &s->ptg);
1308 if (err)
1309 die("Can't start thread for copying data: %s", strerror(err));
1311 ret |= tloop_join(gtp_thread, "Git to program copy");
1312 ret |= tloop_join(ptg_thread, "Program to git copy");
1313 return ret;
1315 #else
1317 /* Close the source and target (for writing) for transfer. */
1318 static void udt_kill_transfer(struct unidirectional_transfer *t)
1320 t->state = SSTATE_FINISHED;
1322 * Socket read end left open isn't a disaster if nobody
1323 * attempts to read from it (mingw compat headers do not
1324 * have SHUT_RD)...
1326 * We can't fully close the socket since otherwise gtp
1327 * task would first close the socket it sends data to
1328 * while closing the ptg file descriptors.
1330 if (!t->src_is_sock)
1331 close(t->src);
1332 if (t->dest_is_sock)
1333 shutdown(t->dest, SHUT_WR);
1334 else
1335 close(t->dest);
1339 * Join process, with appropriate errors on failure. Name is name for the
1340 * process (for error messages). Returns 0 on success, 1 on failure.
1342 static int tloop_join(pid_t pid, const char *name)
1344 int tret;
1345 if (waitpid(pid, &tret, 0) < 0) {
1346 error_errno("%s process failed to wait", name);
1347 return 1;
1349 if (!WIFEXITED(tret) || WEXITSTATUS(tret)) {
1350 error("%s process failed", name);
1351 return 1;
1353 return 0;
1357 * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1358 * -1 on failure.
1360 static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1362 pid_t pid1, pid2;
1363 int ret = 0;
1365 /* Fork thread #1: git to program. */
1366 pid1 = fork();
1367 if (pid1 < 0)
1368 die_errno("Can't start thread for copying data");
1369 else if (pid1 == 0) {
1370 udt_kill_transfer(&s->ptg);
1371 exit(udt_copy_task_routine(&s->gtp) ? 0 : 1);
1374 /* Fork thread #2: program to git. */
1375 pid2 = fork();
1376 if (pid2 < 0)
1377 die_errno("Can't start thread for copying data");
1378 else if (pid2 == 0) {
1379 udt_kill_transfer(&s->gtp);
1380 exit(udt_copy_task_routine(&s->ptg) ? 0 : 1);
1384 * Close both streams in parent as to not interfere with
1385 * end of file detection and wait for both tasks to finish.
1387 udt_kill_transfer(&s->gtp);
1388 udt_kill_transfer(&s->ptg);
1389 ret |= tloop_join(pid1, "Git to program copy");
1390 ret |= tloop_join(pid2, "Program to git copy");
1391 return ret;
1393 #endif
1396 * Copies data from stdin to output and from input to stdout simultaneously.
1397 * Additionally filtering through given filter. If filter is NULL, uses
1398 * identity filter.
1400 int bidirectional_transfer_loop(int input, int output)
1402 struct bidirectional_transfer_state state;
1404 /* Fill the state fields. */
1405 state.ptg.src = input;
1406 state.ptg.dest = 1;
1407 state.ptg.src_is_sock = (input == output);
1408 state.ptg.dest_is_sock = 0;
1409 state.ptg.state = SSTATE_TRANSFERRING;
1410 state.ptg.bufuse = 0;
1411 state.ptg.src_name = "remote input";
1412 state.ptg.dest_name = "stdout";
1414 state.gtp.src = 0;
1415 state.gtp.dest = output;
1416 state.gtp.src_is_sock = 0;
1417 state.gtp.dest_is_sock = (input == output);
1418 state.gtp.state = SSTATE_TRANSFERRING;
1419 state.gtp.bufuse = 0;
1420 state.gtp.src_name = "stdin";
1421 state.gtp.dest_name = "remote output";
1423 return tloop_spawnwait_tasks(&state);