worktree: say that "add" takes an arbitrary commit in short-help
[git.git] / transport-helper.c
blobbf05a2dcf1073ad3b84b030cd9e866c6e5414792
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) < 0)
48 die_errno("Full write to remote helper failed");
51 static int recvline_fh(FILE *helper, struct strbuf *buffer, const char *name)
53 strbuf_reset(buffer);
54 if (debug)
55 fprintf(stderr, "Debug: Remote helper: Waiting...\n");
56 if (strbuf_getline(buffer, helper) == EOF) {
57 if (debug)
58 fprintf(stderr, "Debug: Remote helper quit.\n");
59 return 1;
62 if (debug)
63 fprintf(stderr, "Debug: Remote helper: <- %s\n", buffer->buf);
64 return 0;
67 static int recvline(struct helper_data *helper, struct strbuf *buffer)
69 return recvline_fh(helper->out, buffer, helper->name);
72 static void write_constant(int fd, const char *str)
74 if (debug)
75 fprintf(stderr, "Debug: Remote helper: -> %s", str);
76 if (write_in_full(fd, str, strlen(str)) < 0)
77 die_errno("Full write to remote helper failed");
80 static const char *remove_ext_force(const char *url)
82 if (url) {
83 const char *colon = strchr(url, ':');
84 if (colon && colon[1] == ':')
85 return colon + 2;
87 return url;
90 static void do_take_over(struct transport *transport)
92 struct helper_data *data;
93 data = (struct helper_data *)transport->data;
94 transport_take_over(transport, data->helper);
95 fclose(data->out);
96 free(data);
99 static void standard_options(struct transport *t);
101 static struct child_process *get_helper(struct transport *transport)
103 struct helper_data *data = transport->data;
104 struct strbuf buf = STRBUF_INIT;
105 struct child_process *helper;
106 const char **refspecs = NULL;
107 int refspec_nr = 0;
108 int refspec_alloc = 0;
109 int duped;
110 int code;
112 if (data->helper)
113 return data->helper;
115 helper = xmalloc(sizeof(*helper));
116 child_process_init(helper);
117 helper->in = -1;
118 helper->out = -1;
119 helper->err = 0;
120 argv_array_pushf(&helper->args, "git-remote-%s", data->name);
121 argv_array_push(&helper->args, transport->remote->name);
122 argv_array_push(&helper->args, remove_ext_force(transport->url));
123 helper->git_cmd = 0;
124 helper->silent_exec_failure = 1;
126 if (have_git_dir())
127 argv_array_pushf(&helper->env_array, "%s=%s",
128 GIT_DIR_ENVIRONMENT, get_git_dir());
130 code = start_command(helper);
131 if (code < 0 && errno == ENOENT)
132 die("Unable to find remote helper for '%s'", data->name);
133 else if (code != 0)
134 exit(code);
136 data->helper = helper;
137 data->no_disconnect_req = 0;
140 * Open the output as FILE* so strbuf_getline_*() family of
141 * functions can be used.
142 * Do this with duped fd because fclose() will close the fd,
143 * and stuff like taking over will require the fd to remain.
145 duped = dup(helper->out);
146 if (duped < 0)
147 die_errno("Can't dup helper output fd");
148 data->out = xfdopen(duped, "r");
150 write_constant(helper->in, "capabilities\n");
152 while (1) {
153 const char *capname, *arg;
154 int mandatory = 0;
155 if (recvline(data, &buf))
156 exit(128);
158 if (!*buf.buf)
159 break;
161 if (*buf.buf == '*') {
162 capname = buf.buf + 1;
163 mandatory = 1;
164 } else
165 capname = buf.buf;
167 if (debug)
168 fprintf(stderr, "Debug: Got cap %s\n", capname);
169 if (!strcmp(capname, "fetch"))
170 data->fetch = 1;
171 else if (!strcmp(capname, "option"))
172 data->option = 1;
173 else if (!strcmp(capname, "push"))
174 data->push = 1;
175 else if (!strcmp(capname, "import"))
176 data->import = 1;
177 else if (!strcmp(capname, "bidi-import"))
178 data->bidi_import = 1;
179 else if (!strcmp(capname, "export"))
180 data->export = 1;
181 else if (!strcmp(capname, "check-connectivity"))
182 data->check_connectivity = 1;
183 else if (!data->refspecs && skip_prefix(capname, "refspec ", &arg)) {
184 ALLOC_GROW(refspecs,
185 refspec_nr + 1,
186 refspec_alloc);
187 refspecs[refspec_nr++] = xstrdup(arg);
188 } else if (!strcmp(capname, "connect")) {
189 data->connect = 1;
190 } else if (!strcmp(capname, "signed-tags")) {
191 data->signed_tags = 1;
192 } else if (skip_prefix(capname, "export-marks ", &arg)) {
193 data->export_marks = xstrdup(arg);
194 } else if (skip_prefix(capname, "import-marks ", &arg)) {
195 data->import_marks = xstrdup(arg);
196 } else if (starts_with(capname, "no-private-update")) {
197 data->no_private_update = 1;
198 } else if (mandatory) {
199 die("Unknown mandatory capability %s. This remote "
200 "helper probably needs newer version of Git.",
201 capname);
204 if (refspecs) {
205 int i;
206 data->refspec_nr = refspec_nr;
207 data->refspecs = parse_fetch_refspec(refspec_nr, refspecs);
208 for (i = 0; i < refspec_nr; i++)
209 free((char *)refspecs[i]);
210 free(refspecs);
211 } else if (data->import || data->bidi_import || data->export) {
212 warning("This remote helper should implement refspec capability.");
214 strbuf_release(&buf);
215 if (debug)
216 fprintf(stderr, "Debug: Capabilities complete.\n");
217 standard_options(transport);
218 return data->helper;
221 static int disconnect_helper(struct transport *transport)
223 struct helper_data *data = transport->data;
224 int res = 0;
226 if (data->helper) {
227 if (debug)
228 fprintf(stderr, "Debug: Disconnecting.\n");
229 if (!data->no_disconnect_req) {
231 * Ignore write errors; there's nothing we can do,
232 * since we're about to close the pipe anyway. And the
233 * most likely error is EPIPE due to the helper dying
234 * to report an error itself.
236 sigchain_push(SIGPIPE, SIG_IGN);
237 xwrite(data->helper->in, "\n", 1);
238 sigchain_pop(SIGPIPE);
240 close(data->helper->in);
241 close(data->helper->out);
242 fclose(data->out);
243 res = finish_command(data->helper);
244 FREE_AND_NULL(data->helper);
246 return res;
249 static const char *unsupported_options[] = {
250 TRANS_OPT_UPLOADPACK,
251 TRANS_OPT_RECEIVEPACK,
252 TRANS_OPT_THIN,
253 TRANS_OPT_KEEP
256 static const char *boolean_options[] = {
257 TRANS_OPT_THIN,
258 TRANS_OPT_KEEP,
259 TRANS_OPT_FOLLOWTAGS,
260 TRANS_OPT_DEEPEN_RELATIVE
263 static int strbuf_set_helper_option(struct helper_data *data,
264 struct strbuf *buf)
266 int ret;
268 sendline(data, buf);
269 if (recvline(data, buf))
270 exit(128);
272 if (!strcmp(buf->buf, "ok"))
273 ret = 0;
274 else if (starts_with(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;
282 return ret;
285 static int string_list_set_helper_option(struct helper_data *data,
286 const char *name,
287 struct string_list *list)
289 struct strbuf buf = STRBUF_INIT;
290 int i, ret = 0;
292 for (i = 0; i < list->nr; i++) {
293 strbuf_addf(&buf, "option %s ", name);
294 quote_c_style(list->items[i].string, &buf, NULL, 0);
295 strbuf_addch(&buf, '\n');
297 if ((ret = strbuf_set_helper_option(data, &buf)))
298 break;
299 strbuf_reset(&buf);
301 strbuf_release(&buf);
302 return ret;
305 static int set_helper_option(struct transport *transport,
306 const char *name, const char *value)
308 struct helper_data *data = transport->data;
309 struct strbuf buf = STRBUF_INIT;
310 int i, ret, is_bool = 0;
312 get_helper(transport);
314 if (!data->option)
315 return 1;
317 if (!strcmp(name, "deepen-not"))
318 return string_list_set_helper_option(data, name,
319 (struct string_list *)value);
321 for (i = 0; i < ARRAY_SIZE(unsupported_options); i++) {
322 if (!strcmp(name, unsupported_options[i]))
323 return 1;
326 for (i = 0; i < ARRAY_SIZE(boolean_options); i++) {
327 if (!strcmp(name, boolean_options[i])) {
328 is_bool = 1;
329 break;
333 strbuf_addf(&buf, "option %s ", name);
334 if (is_bool)
335 strbuf_addstr(&buf, value ? "true" : "false");
336 else
337 quote_c_style(value, &buf, NULL, 0);
338 strbuf_addch(&buf, '\n');
340 ret = strbuf_set_helper_option(data, &buf);
341 strbuf_release(&buf);
342 return ret;
345 static void standard_options(struct transport *t)
347 char buf[16];
348 int v = t->verbose;
350 set_helper_option(t, "progress", t->progress ? "true" : "false");
352 xsnprintf(buf, sizeof(buf), "%d", v + 1);
353 set_helper_option(t, "verbosity", buf);
355 switch (t->family) {
356 case TRANSPORT_FAMILY_ALL:
358 * this is already the default,
359 * do not break old remote helpers by setting "all" here
361 break;
362 case TRANSPORT_FAMILY_IPV4:
363 set_helper_option(t, "family", "ipv4");
364 break;
365 case TRANSPORT_FAMILY_IPV6:
366 set_helper_option(t, "family", "ipv6");
367 break;
371 static int release_helper(struct transport *transport)
373 int res = 0;
374 struct helper_data *data = transport->data;
375 free_refspec(data->refspec_nr, data->refspecs);
376 data->refspecs = NULL;
377 res = disconnect_helper(transport);
378 free(transport->data);
379 return res;
382 static int fetch_with_fetch(struct transport *transport,
383 int nr_heads, struct ref **to_fetch)
385 struct helper_data *data = transport->data;
386 int i;
387 struct strbuf buf = STRBUF_INIT;
389 for (i = 0; i < nr_heads; i++) {
390 const struct ref *posn = to_fetch[i];
391 if (posn->status & REF_STATUS_UPTODATE)
392 continue;
394 strbuf_addf(&buf, "fetch %s %s\n",
395 oid_to_hex(&posn->old_oid),
396 posn->symref ? posn->symref : posn->name);
399 strbuf_addch(&buf, '\n');
400 sendline(data, &buf);
402 while (1) {
403 if (recvline(data, &buf))
404 exit(128);
406 if (starts_with(buf.buf, "lock ")) {
407 const char *name = buf.buf + 5;
408 if (transport->pack_lockfile)
409 warning("%s also locked %s", data->name, name);
410 else
411 transport->pack_lockfile = xstrdup(name);
413 else if (data->check_connectivity &&
414 data->transport_options.check_self_contained_and_connected &&
415 !strcmp(buf.buf, "connectivity-ok"))
416 data->transport_options.self_contained_and_connected = 1;
417 else if (!buf.len)
418 break;
419 else
420 warning("%s unexpectedly said: '%s'", data->name, buf.buf);
422 strbuf_release(&buf);
423 return 0;
426 static int get_importer(struct transport *transport, struct child_process *fastimport)
428 struct child_process *helper = get_helper(transport);
429 struct helper_data *data = transport->data;
430 int cat_blob_fd, code;
431 child_process_init(fastimport);
432 fastimport->in = helper->out;
433 argv_array_push(&fastimport->args, "fast-import");
434 argv_array_push(&fastimport->args, debug ? "--stats" : "--quiet");
436 if (data->bidi_import) {
437 cat_blob_fd = xdup(helper->in);
438 argv_array_pushf(&fastimport->args, "--cat-blob-fd=%d", cat_blob_fd);
440 fastimport->git_cmd = 1;
442 code = start_command(fastimport);
443 return code;
446 static int get_exporter(struct transport *transport,
447 struct child_process *fastexport,
448 struct string_list *revlist_args)
450 struct helper_data *data = transport->data;
451 struct child_process *helper = get_helper(transport);
452 int i;
454 child_process_init(fastexport);
456 /* we need to duplicate helper->in because we want to use it after
457 * fastexport is done with it. */
458 fastexport->out = dup(helper->in);
459 argv_array_push(&fastexport->args, "fast-export");
460 argv_array_push(&fastexport->args, "--use-done-feature");
461 argv_array_push(&fastexport->args, data->signed_tags ?
462 "--signed-tags=verbatim" : "--signed-tags=warn-strip");
463 if (data->export_marks)
464 argv_array_pushf(&fastexport->args, "--export-marks=%s.tmp", data->export_marks);
465 if (data->import_marks)
466 argv_array_pushf(&fastexport->args, "--import-marks=%s", data->import_marks);
468 for (i = 0; i < revlist_args->nr; i++)
469 argv_array_push(&fastexport->args, revlist_args->items[i].string);
471 fastexport->git_cmd = 1;
472 return start_command(fastexport);
475 static int fetch_with_import(struct transport *transport,
476 int nr_heads, struct ref **to_fetch)
478 struct child_process fastimport;
479 struct helper_data *data = transport->data;
480 int i;
481 struct ref *posn;
482 struct strbuf buf = STRBUF_INIT;
484 get_helper(transport);
486 if (get_importer(transport, &fastimport))
487 die("Couldn't run fast-import");
489 for (i = 0; i < nr_heads; i++) {
490 posn = to_fetch[i];
491 if (posn->status & REF_STATUS_UPTODATE)
492 continue;
494 strbuf_addf(&buf, "import %s\n",
495 posn->symref ? posn->symref : posn->name);
496 sendline(data, &buf);
497 strbuf_reset(&buf);
500 write_constant(data->helper->in, "\n");
502 * remote-helpers that advertise the bidi-import capability are required to
503 * buffer the complete batch of import commands until this newline before
504 * sending data to fast-import.
505 * These helpers read back data from fast-import on their stdin, which could
506 * be mixed with import commands, otherwise.
509 if (finish_command(&fastimport))
510 die("Error while running fast-import");
513 * The fast-import stream of a remote helper that advertises
514 * the "refspec" capability writes to the refs named after the
515 * right hand side of the first refspec matching each ref we
516 * were fetching.
518 * (If no "refspec" capability was specified, for historical
519 * reasons we default to the equivalent of *:*.)
521 * Store the result in to_fetch[i].old_sha1. Callers such
522 * as "git fetch" can use the value to write feedback to the
523 * terminal, populate FETCH_HEAD, and determine what new value
524 * should be written to peer_ref if the update is a
525 * fast-forward or this is a forced update.
527 for (i = 0; i < nr_heads; i++) {
528 char *private, *name;
529 posn = to_fetch[i];
530 if (posn->status & REF_STATUS_UPTODATE)
531 continue;
532 name = posn->symref ? posn->symref : posn->name;
533 if (data->refspecs)
534 private = apply_refspecs(data->refspecs, data->refspec_nr, name);
535 else
536 private = xstrdup(name);
537 if (private) {
538 if (read_ref(private, &posn->old_oid) < 0)
539 die("Could not read ref %s", private);
540 free(private);
543 strbuf_release(&buf);
544 return 0;
547 static int process_connect_service(struct transport *transport,
548 const char *name, const char *exec)
550 struct helper_data *data = transport->data;
551 struct strbuf cmdbuf = STRBUF_INIT;
552 struct child_process *helper;
553 int r, duped, ret = 0;
554 FILE *input;
556 helper = get_helper(transport);
559 * Yes, dup the pipe another time, as we need unbuffered version
560 * of input pipe as FILE*. fclose() closes the underlying fd and
561 * stream buffering only can be changed before first I/O operation
562 * on it.
564 duped = dup(helper->out);
565 if (duped < 0)
566 die_errno("Can't dup helper output fd");
567 input = xfdopen(duped, "r");
568 setvbuf(input, NULL, _IONBF, 0);
571 * Handle --upload-pack and friends. This is fire and forget...
572 * just warn if it fails.
574 if (strcmp(name, exec)) {
575 r = set_helper_option(transport, "servpath", exec);
576 if (r > 0)
577 warning("Setting remote service path not supported by protocol.");
578 else if (r < 0)
579 warning("Invalid remote service path.");
582 if (data->connect)
583 strbuf_addf(&cmdbuf, "connect %s\n", name);
584 else
585 goto exit;
587 sendline(data, &cmdbuf);
588 if (recvline_fh(input, &cmdbuf, name))
589 exit(128);
591 if (!strcmp(cmdbuf.buf, "")) {
592 data->no_disconnect_req = 1;
593 if (debug)
594 fprintf(stderr, "Debug: Smart transport connection "
595 "ready.\n");
596 ret = 1;
597 } else if (!strcmp(cmdbuf.buf, "fallback")) {
598 if (debug)
599 fprintf(stderr, "Debug: Falling back to dumb "
600 "transport.\n");
601 } else
602 die("Unknown response to connect: %s",
603 cmdbuf.buf);
605 exit:
606 strbuf_release(&cmdbuf);
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, NULL,
799 0, 0);
800 free(private);
802 strbuf_release(&buf);
803 return ret;
806 static void set_common_push_options(struct transport *transport,
807 const char *name, int flags)
809 if (flags & TRANSPORT_PUSH_DRY_RUN) {
810 if (set_helper_option(transport, "dry-run", "true") != 0)
811 die("helper %s does not support dry-run", name);
812 } else if (flags & TRANSPORT_PUSH_CERT_ALWAYS) {
813 if (set_helper_option(transport, TRANS_OPT_PUSH_CERT, "true") != 0)
814 die("helper %s does not support --signed", name);
815 } else if (flags & TRANSPORT_PUSH_CERT_IF_ASKED) {
816 if (set_helper_option(transport, TRANS_OPT_PUSH_CERT, "if-asked") != 0)
817 die("helper %s does not support --signed=if-asked", name);
820 if (flags & TRANSPORT_PUSH_OPTIONS) {
821 struct string_list_item *item;
822 for_each_string_list_item(item, transport->push_options)
823 if (set_helper_option(transport, "push-option", item->string) != 0)
824 die("helper %s does not support 'push-option'", name);
828 static int push_refs_with_push(struct transport *transport,
829 struct ref *remote_refs, int flags)
831 int force_all = flags & TRANSPORT_PUSH_FORCE;
832 int mirror = flags & TRANSPORT_PUSH_MIRROR;
833 struct helper_data *data = transport->data;
834 struct strbuf buf = STRBUF_INIT;
835 struct ref *ref;
836 struct string_list cas_options = STRING_LIST_INIT_DUP;
837 struct string_list_item *cas_option;
839 get_helper(transport);
840 if (!data->push)
841 return 1;
843 for (ref = remote_refs; ref; ref = ref->next) {
844 if (!ref->peer_ref && !mirror)
845 continue;
847 /* Check for statuses set by set_ref_status_for_push() */
848 switch (ref->status) {
849 case REF_STATUS_REJECT_NONFASTFORWARD:
850 case REF_STATUS_REJECT_STALE:
851 case REF_STATUS_REJECT_ALREADY_EXISTS:
852 case REF_STATUS_UPTODATE:
853 continue;
854 default:
855 ; /* do nothing */
858 if (force_all)
859 ref->force = 1;
861 strbuf_addstr(&buf, "push ");
862 if (!ref->deletion) {
863 if (ref->force)
864 strbuf_addch(&buf, '+');
865 if (ref->peer_ref)
866 strbuf_addstr(&buf, ref->peer_ref->name);
867 else
868 strbuf_addstr(&buf, oid_to_hex(&ref->new_oid));
870 strbuf_addch(&buf, ':');
871 strbuf_addstr(&buf, ref->name);
872 strbuf_addch(&buf, '\n');
875 * The "--force-with-lease" options without explicit
876 * values to expect have already been expanded into
877 * the ref->old_oid_expect[] field; we can ignore
878 * transport->smart_options->cas altogether and instead
879 * can enumerate them from the refs.
881 if (ref->expect_old_sha1) {
882 struct strbuf cas = STRBUF_INIT;
883 strbuf_addf(&cas, "%s:%s",
884 ref->name, oid_to_hex(&ref->old_oid_expect));
885 string_list_append(&cas_options, strbuf_detach(&cas, NULL));
888 if (buf.len == 0) {
889 string_list_clear(&cas_options, 0);
890 return 0;
893 for_each_string_list_item(cas_option, &cas_options)
894 set_helper_option(transport, "cas", cas_option->string);
895 set_common_push_options(transport, data->name, flags);
897 strbuf_addch(&buf, '\n');
898 sendline(data, &buf);
899 strbuf_release(&buf);
901 return push_update_refs_status(data, remote_refs, flags);
904 static int push_refs_with_export(struct transport *transport,
905 struct ref *remote_refs, int flags)
907 struct ref *ref;
908 struct child_process *helper, exporter;
909 struct helper_data *data = transport->data;
910 struct string_list revlist_args = STRING_LIST_INIT_DUP;
911 struct strbuf buf = STRBUF_INIT;
913 if (!data->refspecs)
914 die("remote-helper doesn't support push; refspec needed");
916 set_common_push_options(transport, data->name, flags);
917 if (flags & TRANSPORT_PUSH_FORCE) {
918 if (set_helper_option(transport, "force", "true") != 0)
919 warning("helper %s does not support 'force'", data->name);
922 helper = get_helper(transport);
924 write_constant(helper->in, "export\n");
926 for (ref = remote_refs; ref; ref = ref->next) {
927 char *private;
928 struct object_id oid;
930 private = apply_refspecs(data->refspecs, data->refspec_nr, ref->name);
931 if (private && !get_oid(private, &oid)) {
932 strbuf_addf(&buf, "^%s", private);
933 string_list_append(&revlist_args, strbuf_detach(&buf, NULL));
934 oidcpy(&ref->old_oid, &oid);
936 free(private);
938 if (ref->peer_ref) {
939 if (strcmp(ref->name, ref->peer_ref->name)) {
940 if (!ref->deletion) {
941 const char *name;
942 int flag;
944 /* Follow symbolic refs (mainly for HEAD). */
945 name = resolve_ref_unsafe(ref->peer_ref->name,
946 RESOLVE_REF_READING,
947 &oid, &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, &(*tail)->old_oid) < 0)
1070 die(_("Could not read ref %s"),
1071 (*tail)->name);
1074 tail = &((*tail)->next);
1076 if (debug)
1077 fprintf(stderr, "Debug: Read ref listing.\n");
1078 strbuf_release(&buf);
1080 for (posn = ret; posn; posn = posn->next)
1081 resolve_remote_symref(posn, ret);
1083 return ret;
1086 int transport_helper_init(struct transport *transport, const char *name)
1088 struct helper_data *data = xcalloc(1, sizeof(*data));
1089 data->name = name;
1091 transport_check_allowed(name);
1093 if (getenv("GIT_TRANSPORT_HELPER_DEBUG"))
1094 debug = 1;
1096 transport->data = data;
1097 transport->set_option = set_helper_option;
1098 transport->get_refs_list = get_refs_list;
1099 transport->fetch = fetch;
1100 transport->push_refs = push_refs;
1101 transport->disconnect = release_helper;
1102 transport->connect = connect_helper;
1103 transport->smart_options = &(data->transport_options);
1104 return 0;
1108 * Linux pipes can buffer 65536 bytes at once (and most platforms can
1109 * buffer less), so attempt reads and writes with up to that size.
1111 #define BUFFERSIZE 65536
1112 /* This should be enough to hold debugging message. */
1113 #define PBUFFERSIZE 8192
1115 /* Print bidirectional transfer loop debug message. */
1116 __attribute__((format (printf, 1, 2)))
1117 static void transfer_debug(const char *fmt, ...)
1120 * NEEDSWORK: This function is sometimes used from multiple threads, and
1121 * we end up using debug_enabled racily. That "should not matter" since
1122 * we always write the same value, but it's still wrong. This function
1123 * is listed in .tsan-suppressions for the time being.
1126 va_list args;
1127 char msgbuf[PBUFFERSIZE];
1128 static int debug_enabled = -1;
1130 if (debug_enabled < 0)
1131 debug_enabled = getenv("GIT_TRANSLOOP_DEBUG") ? 1 : 0;
1132 if (!debug_enabled)
1133 return;
1135 va_start(args, fmt);
1136 vsnprintf(msgbuf, PBUFFERSIZE, fmt, args);
1137 va_end(args);
1138 fprintf(stderr, "Transfer loop debugging: %s\n", msgbuf);
1141 /* Stream state: More data may be coming in this direction. */
1142 #define SSTATE_TRANSFERRING 0
1144 * Stream state: No more data coming in this direction, flushing rest of
1145 * data.
1147 #define SSTATE_FLUSHING 1
1148 /* Stream state: Transfer in this direction finished. */
1149 #define SSTATE_FINISHED 2
1151 #define STATE_NEEDS_READING(state) ((state) <= SSTATE_TRANSFERRING)
1152 #define STATE_NEEDS_WRITING(state) ((state) <= SSTATE_FLUSHING)
1153 #define STATE_NEEDS_CLOSING(state) ((state) == SSTATE_FLUSHING)
1155 /* Unidirectional transfer. */
1156 struct unidirectional_transfer {
1157 /* Source */
1158 int src;
1159 /* Destination */
1160 int dest;
1161 /* Is source socket? */
1162 int src_is_sock;
1163 /* Is destination socket? */
1164 int dest_is_sock;
1165 /* Transfer state (TRANSFERRING/FLUSHING/FINISHED) */
1166 int state;
1167 /* Buffer. */
1168 char buf[BUFFERSIZE];
1169 /* Buffer used. */
1170 size_t bufuse;
1171 /* Name of source. */
1172 const char *src_name;
1173 /* Name of destination. */
1174 const char *dest_name;
1177 /* Closes the target (for writing) if transfer has finished. */
1178 static void udt_close_if_finished(struct unidirectional_transfer *t)
1180 if (STATE_NEEDS_CLOSING(t->state) && !t->bufuse) {
1181 t->state = SSTATE_FINISHED;
1182 if (t->dest_is_sock)
1183 shutdown(t->dest, SHUT_WR);
1184 else
1185 close(t->dest);
1186 transfer_debug("Closed %s.", t->dest_name);
1191 * Tries to read data from source into buffer. If buffer is full,
1192 * no data is read. Returns 0 on success, -1 on error.
1194 static int udt_do_read(struct unidirectional_transfer *t)
1196 ssize_t bytes;
1198 if (t->bufuse == BUFFERSIZE)
1199 return 0; /* No space for more. */
1201 transfer_debug("%s is readable", t->src_name);
1202 bytes = read(t->src, t->buf + t->bufuse, BUFFERSIZE - t->bufuse);
1203 if (bytes < 0 && errno != EWOULDBLOCK && errno != EAGAIN &&
1204 errno != EINTR) {
1205 error_errno("read(%s) failed", t->src_name);
1206 return -1;
1207 } else if (bytes == 0) {
1208 transfer_debug("%s EOF (with %i bytes in buffer)",
1209 t->src_name, (int)t->bufuse);
1210 t->state = SSTATE_FLUSHING;
1211 } else if (bytes > 0) {
1212 t->bufuse += bytes;
1213 transfer_debug("Read %i bytes from %s (buffer now at %i)",
1214 (int)bytes, t->src_name, (int)t->bufuse);
1216 return 0;
1219 /* Tries to write data from buffer into destination. If buffer is empty,
1220 * no data is written. Returns 0 on success, -1 on error.
1222 static int udt_do_write(struct unidirectional_transfer *t)
1224 ssize_t bytes;
1226 if (t->bufuse == 0)
1227 return 0; /* Nothing to write. */
1229 transfer_debug("%s is writable", t->dest_name);
1230 bytes = xwrite(t->dest, t->buf, t->bufuse);
1231 if (bytes < 0 && errno != EWOULDBLOCK) {
1232 error_errno("write(%s) failed", t->dest_name);
1233 return -1;
1234 } else if (bytes > 0) {
1235 t->bufuse -= bytes;
1236 if (t->bufuse)
1237 memmove(t->buf, t->buf + bytes, t->bufuse);
1238 transfer_debug("Wrote %i bytes to %s (buffer now at %i)",
1239 (int)bytes, t->dest_name, (int)t->bufuse);
1241 return 0;
1245 /* State of bidirectional transfer loop. */
1246 struct bidirectional_transfer_state {
1247 /* Direction from program to git. */
1248 struct unidirectional_transfer ptg;
1249 /* Direction from git to program. */
1250 struct unidirectional_transfer gtp;
1253 static void *udt_copy_task_routine(void *udt)
1255 struct unidirectional_transfer *t = (struct unidirectional_transfer *)udt;
1256 while (t->state != SSTATE_FINISHED) {
1257 if (STATE_NEEDS_READING(t->state))
1258 if (udt_do_read(t))
1259 return NULL;
1260 if (STATE_NEEDS_WRITING(t->state))
1261 if (udt_do_write(t))
1262 return NULL;
1263 if (STATE_NEEDS_CLOSING(t->state))
1264 udt_close_if_finished(t);
1266 return udt; /* Just some non-NULL value. */
1269 #ifndef NO_PTHREADS
1272 * Join thread, with appropriate errors on failure. Name is name for the
1273 * thread (for error messages). Returns 0 on success, 1 on failure.
1275 static int tloop_join(pthread_t thread, const char *name)
1277 int err;
1278 void *tret;
1279 err = pthread_join(thread, &tret);
1280 if (!tret) {
1281 error("%s thread failed", name);
1282 return 1;
1284 if (err) {
1285 error("%s thread failed to join: %s", name, strerror(err));
1286 return 1;
1288 return 0;
1292 * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1293 * -1 on failure.
1295 static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1297 pthread_t gtp_thread;
1298 pthread_t ptg_thread;
1299 int err;
1300 int ret = 0;
1301 err = pthread_create(&gtp_thread, NULL, udt_copy_task_routine,
1302 &s->gtp);
1303 if (err)
1304 die("Can't start thread for copying data: %s", strerror(err));
1305 err = pthread_create(&ptg_thread, NULL, udt_copy_task_routine,
1306 &s->ptg);
1307 if (err)
1308 die("Can't start thread for copying data: %s", strerror(err));
1310 ret |= tloop_join(gtp_thread, "Git to program copy");
1311 ret |= tloop_join(ptg_thread, "Program to git copy");
1312 return ret;
1314 #else
1316 /* Close the source and target (for writing) for transfer. */
1317 static void udt_kill_transfer(struct unidirectional_transfer *t)
1319 t->state = SSTATE_FINISHED;
1321 * Socket read end left open isn't a disaster if nobody
1322 * attempts to read from it (mingw compat headers do not
1323 * have SHUT_RD)...
1325 * We can't fully close the socket since otherwise gtp
1326 * task would first close the socket it sends data to
1327 * while closing the ptg file descriptors.
1329 if (!t->src_is_sock)
1330 close(t->src);
1331 if (t->dest_is_sock)
1332 shutdown(t->dest, SHUT_WR);
1333 else
1334 close(t->dest);
1338 * Join process, with appropriate errors on failure. Name is name for the
1339 * process (for error messages). Returns 0 on success, 1 on failure.
1341 static int tloop_join(pid_t pid, const char *name)
1343 int tret;
1344 if (waitpid(pid, &tret, 0) < 0) {
1345 error_errno("%s process failed to wait", name);
1346 return 1;
1348 if (!WIFEXITED(tret) || WEXITSTATUS(tret)) {
1349 error("%s process failed", name);
1350 return 1;
1352 return 0;
1356 * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1357 * -1 on failure.
1359 static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1361 pid_t pid1, pid2;
1362 int ret = 0;
1364 /* Fork thread #1: git to program. */
1365 pid1 = fork();
1366 if (pid1 < 0)
1367 die_errno("Can't start thread for copying data");
1368 else if (pid1 == 0) {
1369 udt_kill_transfer(&s->ptg);
1370 exit(udt_copy_task_routine(&s->gtp) ? 0 : 1);
1373 /* Fork thread #2: program to git. */
1374 pid2 = fork();
1375 if (pid2 < 0)
1376 die_errno("Can't start thread for copying data");
1377 else if (pid2 == 0) {
1378 udt_kill_transfer(&s->gtp);
1379 exit(udt_copy_task_routine(&s->ptg) ? 0 : 1);
1383 * Close both streams in parent as to not interfere with
1384 * end of file detection and wait for both tasks to finish.
1386 udt_kill_transfer(&s->gtp);
1387 udt_kill_transfer(&s->ptg);
1388 ret |= tloop_join(pid1, "Git to program copy");
1389 ret |= tloop_join(pid2, "Program to git copy");
1390 return ret;
1392 #endif
1395 * Copies data from stdin to output and from input to stdout simultaneously.
1396 * Additionally filtering through given filter. If filter is NULL, uses
1397 * identity filter.
1399 int bidirectional_transfer_loop(int input, int output)
1401 struct bidirectional_transfer_state state;
1403 /* Fill the state fields. */
1404 state.ptg.src = input;
1405 state.ptg.dest = 1;
1406 state.ptg.src_is_sock = (input == output);
1407 state.ptg.dest_is_sock = 0;
1408 state.ptg.state = SSTATE_TRANSFERRING;
1409 state.ptg.bufuse = 0;
1410 state.ptg.src_name = "remote input";
1411 state.ptg.dest_name = "stdout";
1413 state.gtp.src = 0;
1414 state.gtp.dest = output;
1415 state.gtp.src_is_sock = 0;
1416 state.gtp.dest_is_sock = (input == output);
1417 state.gtp.state = SSTATE_TRANSFERRING;
1418 state.gtp.bufuse = 0;
1419 state.gtp.src_name = "stdin";
1420 state.gtp.dest_name = "remote output";
1422 return tloop_spawnwait_tasks(&state);