Update draft release notes to 2.2
[git/debian.git] / transport-helper.c
blob080a7a6ae23e6915c425a3e471fd641aabafba90
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"
14 #include "refs.h"
16 static int debug;
18 struct helper_data {
19 const char *name;
20 struct child_process *helper;
21 FILE *out;
22 unsigned fetch : 1,
23 import : 1,
24 bidi_import : 1,
25 export : 1,
26 option : 1,
27 push : 1,
28 connect : 1,
29 signed_tags : 1,
30 check_connectivity : 1,
31 no_disconnect_req : 1,
32 no_private_update : 1;
33 char *export_marks;
34 char *import_marks;
35 /* These go from remote name (as in "list") to private name */
36 struct refspec *refspecs;
37 int refspec_nr;
38 /* Transport options for fetch-pack/send-pack (should one of
39 * those be invoked).
41 struct git_transport_options transport_options;
44 static void sendline(struct helper_data *helper, struct strbuf *buffer)
46 if (debug)
47 fprintf(stderr, "Debug: Remote helper: -> %s", buffer->buf);
48 if (write_in_full(helper->helper->in, buffer->buf, buffer->len)
49 != buffer->len)
50 die_errno("Full write to remote helper failed");
53 static int recvline_fh(FILE *helper, struct strbuf *buffer, const char *name)
55 strbuf_reset(buffer);
56 if (debug)
57 fprintf(stderr, "Debug: Remote helper: Waiting...\n");
58 if (strbuf_getline(buffer, helper, '\n') == EOF) {
59 if (debug)
60 fprintf(stderr, "Debug: Remote helper quit.\n");
61 return 1;
64 if (debug)
65 fprintf(stderr, "Debug: Remote helper: <- %s\n", buffer->buf);
66 return 0;
69 static int recvline(struct helper_data *helper, struct strbuf *buffer)
71 return recvline_fh(helper->out, buffer, helper->name);
74 static void write_constant(int fd, const char *str)
76 if (debug)
77 fprintf(stderr, "Debug: Remote helper: -> %s", str);
78 if (write_in_full(fd, str, strlen(str)) != strlen(str))
79 die_errno("Full write to remote helper failed");
82 static const char *remove_ext_force(const char *url)
84 if (url) {
85 const char *colon = strchr(url, ':');
86 if (colon && colon[1] == ':')
87 return colon + 2;
89 return url;
92 static void do_take_over(struct transport *transport)
94 struct helper_data *data;
95 data = (struct helper_data *)transport->data;
96 transport_take_over(transport, data->helper);
97 fclose(data->out);
98 free(data);
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;
111 char git_dir_buf[sizeof(GIT_DIR_ENVIRONMENT) + PATH_MAX + 1];
112 const char *helper_env[] = {
113 git_dir_buf,
114 NULL
118 if (data->helper)
119 return data->helper;
121 helper = xmalloc(sizeof(*helper));
122 child_process_init(helper);
123 helper->in = -1;
124 helper->out = -1;
125 helper->err = 0;
126 argv_array_pushf(&helper->args, "git-remote-%s", data->name);
127 argv_array_push(&helper->args, transport->remote->name);
128 argv_array_push(&helper->args, remove_ext_force(transport->url));
129 helper->git_cmd = 0;
130 helper->silent_exec_failure = 1;
132 snprintf(git_dir_buf, sizeof(git_dir_buf), "%s=%s", GIT_DIR_ENVIRONMENT, get_git_dir());
133 helper->env = helper_env;
135 code = start_command(helper);
136 if (code < 0 && errno == ENOENT)
137 die("Unable to find remote helper for '%s'", data->name);
138 else if (code != 0)
139 exit(code);
141 data->helper = helper;
142 data->no_disconnect_req = 0;
145 * Open the output as FILE* so strbuf_getline() can be used.
146 * Do this with duped fd because fclose() will close the fd,
147 * and stuff like taking over will require the fd to remain.
149 duped = dup(helper->out);
150 if (duped < 0)
151 die_errno("Can't dup helper output fd");
152 data->out = xfdopen(duped, "r");
154 write_constant(helper->in, "capabilities\n");
156 while (1) {
157 const char *capname, *arg;
158 int mandatory = 0;
159 if (recvline(data, &buf))
160 exit(128);
162 if (!*buf.buf)
163 break;
165 if (*buf.buf == '*') {
166 capname = buf.buf + 1;
167 mandatory = 1;
168 } else
169 capname = buf.buf;
171 if (debug)
172 fprintf(stderr, "Debug: Got cap %s\n", capname);
173 if (!strcmp(capname, "fetch"))
174 data->fetch = 1;
175 else if (!strcmp(capname, "option"))
176 data->option = 1;
177 else if (!strcmp(capname, "push"))
178 data->push = 1;
179 else if (!strcmp(capname, "import"))
180 data->import = 1;
181 else if (!strcmp(capname, "bidi-import"))
182 data->bidi_import = 1;
183 else if (!strcmp(capname, "export"))
184 data->export = 1;
185 else if (!strcmp(capname, "check-connectivity"))
186 data->check_connectivity = 1;
187 else if (!data->refspecs && skip_prefix(capname, "refspec ", &arg)) {
188 ALLOC_GROW(refspecs,
189 refspec_nr + 1,
190 refspec_alloc);
191 refspecs[refspec_nr++] = xstrdup(arg);
192 } else if (!strcmp(capname, "connect")) {
193 data->connect = 1;
194 } else if (!strcmp(capname, "signed-tags")) {
195 data->signed_tags = 1;
196 } else if (skip_prefix(capname, "export-marks ", &arg)) {
197 data->export_marks = xstrdup(arg);
198 } else if (skip_prefix(capname, "import-marks ", &arg)) {
199 data->import_marks = xstrdup(arg);
200 } else if (starts_with(capname, "no-private-update")) {
201 data->no_private_update = 1;
202 } else if (mandatory) {
203 die("Unknown mandatory capability %s. This remote "
204 "helper probably needs newer version of Git.",
205 capname);
208 if (refspecs) {
209 int i;
210 data->refspec_nr = refspec_nr;
211 data->refspecs = parse_fetch_refspec(refspec_nr, refspecs);
212 for (i = 0; i < refspec_nr; i++)
213 free((char *)refspecs[i]);
214 free(refspecs);
215 } else if (data->import || data->bidi_import || data->export) {
216 warning("This remote helper should implement refspec capability.");
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 free(data->helper);
248 data->helper = NULL;
250 return res;
253 static const char *unsupported_options[] = {
254 TRANS_OPT_UPLOADPACK,
255 TRANS_OPT_RECEIVEPACK,
256 TRANS_OPT_THIN,
257 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 sendline(data, &buf);
298 if (recvline(data, &buf))
299 exit(128);
301 if (!strcmp(buf.buf, "ok"))
302 ret = 0;
303 else if (starts_with(buf.buf, "error")) {
304 ret = -1;
305 } else if (!strcmp(buf.buf, "unsupported"))
306 ret = 1;
307 else {
308 warning("%s unexpectedly said: '%s'", data->name, buf.buf);
309 ret = 1;
311 strbuf_release(&buf);
312 return ret;
315 static void standard_options(struct transport *t)
317 char buf[16];
318 int n;
319 int v = t->verbose;
321 set_helper_option(t, "progress", t->progress ? "true" : "false");
323 n = snprintf(buf, sizeof(buf), "%d", v + 1);
324 if (n >= sizeof(buf))
325 die("impossibly large verbosity value");
326 set_helper_option(t, "verbosity", buf);
329 static int release_helper(struct transport *transport)
331 int res = 0;
332 struct helper_data *data = transport->data;
333 free_refspec(data->refspec_nr, data->refspecs);
334 data->refspecs = NULL;
335 res = disconnect_helper(transport);
336 free(transport->data);
337 return res;
340 static int fetch_with_fetch(struct transport *transport,
341 int nr_heads, struct ref **to_fetch)
343 struct helper_data *data = transport->data;
344 int i;
345 struct strbuf buf = STRBUF_INIT;
347 standard_options(transport);
348 if (data->check_connectivity &&
349 data->transport_options.check_self_contained_and_connected)
350 set_helper_option(transport, "check-connectivity", "true");
352 if (transport->cloning)
353 set_helper_option(transport, "cloning", "true");
355 if (data->transport_options.update_shallow)
356 set_helper_option(transport, "update-shallow", "true");
358 for (i = 0; i < nr_heads; i++) {
359 const struct ref *posn = to_fetch[i];
360 if (posn->status & REF_STATUS_UPTODATE)
361 continue;
363 strbuf_addf(&buf, "fetch %s %s\n",
364 sha1_to_hex(posn->old_sha1), posn->name);
367 strbuf_addch(&buf, '\n');
368 sendline(data, &buf);
370 while (1) {
371 if (recvline(data, &buf))
372 exit(128);
374 if (starts_with(buf.buf, "lock ")) {
375 const char *name = buf.buf + 5;
376 if (transport->pack_lockfile)
377 warning("%s also locked %s", data->name, name);
378 else
379 transport->pack_lockfile = xstrdup(name);
381 else if (data->check_connectivity &&
382 data->transport_options.check_self_contained_and_connected &&
383 !strcmp(buf.buf, "connectivity-ok"))
384 data->transport_options.self_contained_and_connected = 1;
385 else if (!buf.len)
386 break;
387 else
388 warning("%s unexpectedly said: '%s'", data->name, buf.buf);
390 strbuf_release(&buf);
391 return 0;
394 static int get_importer(struct transport *transport, struct child_process *fastimport)
396 struct child_process *helper = get_helper(transport);
397 struct helper_data *data = transport->data;
398 int cat_blob_fd, code;
399 child_process_init(fastimport);
400 fastimport->in = helper->out;
401 argv_array_push(&fastimport->args, "fast-import");
402 argv_array_push(&fastimport->args, debug ? "--stats" : "--quiet");
404 if (data->bidi_import) {
405 cat_blob_fd = xdup(helper->in);
406 argv_array_pushf(&fastimport->args, "--cat-blob-fd=%d", cat_blob_fd);
408 fastimport->git_cmd = 1;
410 code = start_command(fastimport);
411 return code;
414 static int get_exporter(struct transport *transport,
415 struct child_process *fastexport,
416 struct string_list *revlist_args)
418 struct helper_data *data = transport->data;
419 struct child_process *helper = get_helper(transport);
420 int i;
422 memset(fastexport, 0, sizeof(*fastexport));
424 /* we need to duplicate helper->in because we want to use it after
425 * fastexport is done with it. */
426 fastexport->out = dup(helper->in);
427 argv_array_push(&fastexport->args, "fast-export");
428 argv_array_push(&fastexport->args, "--use-done-feature");
429 argv_array_push(&fastexport->args, data->signed_tags ?
430 "--signed-tags=verbatim" : "--signed-tags=warn-strip");
431 if (data->export_marks)
432 argv_array_pushf(&fastexport->args, "--export-marks=%s.tmp", data->export_marks);
433 if (data->import_marks)
434 argv_array_pushf(&fastexport->args, "--import-marks=%s", data->import_marks);
436 for (i = 0; i < revlist_args->nr; i++)
437 argv_array_push(&fastexport->args, revlist_args->items[i].string);
439 fastexport->git_cmd = 1;
440 return start_command(fastexport);
443 static int fetch_with_import(struct transport *transport,
444 int nr_heads, struct ref **to_fetch)
446 struct child_process fastimport;
447 struct helper_data *data = transport->data;
448 int i;
449 struct ref *posn;
450 struct strbuf buf = STRBUF_INIT;
452 get_helper(transport);
454 if (get_importer(transport, &fastimport))
455 die("Couldn't run fast-import");
457 for (i = 0; i < nr_heads; i++) {
458 posn = to_fetch[i];
459 if (posn->status & REF_STATUS_UPTODATE)
460 continue;
462 strbuf_addf(&buf, "import %s\n", posn->name);
463 sendline(data, &buf);
464 strbuf_reset(&buf);
467 write_constant(data->helper->in, "\n");
469 * remote-helpers that advertise the bidi-import capability are required to
470 * buffer the complete batch of import commands until this newline before
471 * sending data to fast-import.
472 * These helpers read back data from fast-import on their stdin, which could
473 * be mixed with import commands, otherwise.
476 if (finish_command(&fastimport))
477 die("Error while running fast-import");
480 * The fast-import stream of a remote helper that advertises
481 * the "refspec" capability writes to the refs named after the
482 * right hand side of the first refspec matching each ref we
483 * were fetching.
485 * (If no "refspec" capability was specified, for historical
486 * reasons we default to the equivalent of *:*.)
488 * Store the result in to_fetch[i].old_sha1. Callers such
489 * as "git fetch" can use the value to write feedback to the
490 * terminal, populate FETCH_HEAD, and determine what new value
491 * should be written to peer_ref if the update is a
492 * fast-forward or this is a forced update.
494 for (i = 0; i < nr_heads; i++) {
495 char *private;
496 posn = to_fetch[i];
497 if (posn->status & REF_STATUS_UPTODATE)
498 continue;
499 if (data->refspecs)
500 private = apply_refspecs(data->refspecs, data->refspec_nr, posn->name);
501 else
502 private = xstrdup(posn->name);
503 if (private) {
504 read_ref(private, posn->old_sha1);
505 free(private);
508 strbuf_release(&buf);
509 return 0;
512 static int process_connect_service(struct transport *transport,
513 const char *name, const char *exec)
515 struct helper_data *data = transport->data;
516 struct strbuf cmdbuf = STRBUF_INIT;
517 struct child_process *helper;
518 int r, duped, ret = 0;
519 FILE *input;
521 helper = get_helper(transport);
524 * Yes, dup the pipe another time, as we need unbuffered version
525 * of input pipe as FILE*. fclose() closes the underlying fd and
526 * stream buffering only can be changed before first I/O operation
527 * on it.
529 duped = dup(helper->out);
530 if (duped < 0)
531 die_errno("Can't dup helper output fd");
532 input = xfdopen(duped, "r");
533 setvbuf(input, NULL, _IONBF, 0);
536 * Handle --upload-pack and friends. This is fire and forget...
537 * just warn if it fails.
539 if (strcmp(name, exec)) {
540 r = set_helper_option(transport, "servpath", exec);
541 if (r > 0)
542 warning("Setting remote service path not supported by protocol.");
543 else if (r < 0)
544 warning("Invalid remote service path.");
547 if (data->connect)
548 strbuf_addf(&cmdbuf, "connect %s\n", name);
549 else
550 goto exit;
552 sendline(data, &cmdbuf);
553 if (recvline_fh(input, &cmdbuf, name))
554 exit(128);
556 if (!strcmp(cmdbuf.buf, "")) {
557 data->no_disconnect_req = 1;
558 if (debug)
559 fprintf(stderr, "Debug: Smart transport connection "
560 "ready.\n");
561 ret = 1;
562 } else if (!strcmp(cmdbuf.buf, "fallback")) {
563 if (debug)
564 fprintf(stderr, "Debug: Falling back to dumb "
565 "transport.\n");
566 } else
567 die("Unknown response to connect: %s",
568 cmdbuf.buf);
570 exit:
571 fclose(input);
572 return ret;
575 static int process_connect(struct transport *transport,
576 int for_push)
578 struct helper_data *data = transport->data;
579 const char *name;
580 const char *exec;
582 name = for_push ? "git-receive-pack" : "git-upload-pack";
583 if (for_push)
584 exec = data->transport_options.receivepack;
585 else
586 exec = data->transport_options.uploadpack;
588 return process_connect_service(transport, name, exec);
591 static int connect_helper(struct transport *transport, const char *name,
592 const char *exec, int fd[2])
594 struct helper_data *data = transport->data;
596 /* Get_helper so connect is inited. */
597 get_helper(transport);
598 if (!data->connect)
599 die("Operation not supported by protocol.");
601 if (!process_connect_service(transport, name, exec))
602 die("Can't connect to subservice %s.", name);
604 fd[0] = data->helper->out;
605 fd[1] = data->helper->in;
606 return 0;
609 static int fetch(struct transport *transport,
610 int nr_heads, struct ref **to_fetch)
612 struct helper_data *data = transport->data;
613 int i, count;
615 if (process_connect(transport, 0)) {
616 do_take_over(transport);
617 return transport->fetch(transport, nr_heads, to_fetch);
620 count = 0;
621 for (i = 0; i < nr_heads; i++)
622 if (!(to_fetch[i]->status & REF_STATUS_UPTODATE))
623 count++;
625 if (!count)
626 return 0;
628 if (data->fetch)
629 return fetch_with_fetch(transport, nr_heads, to_fetch);
631 if (data->import)
632 return fetch_with_import(transport, nr_heads, to_fetch);
634 return -1;
637 static int push_update_ref_status(struct strbuf *buf,
638 struct ref **ref,
639 struct ref *remote_refs)
641 char *refname, *msg;
642 int status, forced = 0;
644 if (starts_with(buf->buf, "ok ")) {
645 status = REF_STATUS_OK;
646 refname = buf->buf + 3;
647 } else if (starts_with(buf->buf, "error ")) {
648 status = REF_STATUS_REMOTE_REJECT;
649 refname = buf->buf + 6;
650 } else
651 die("expected ok/error, helper said '%s'", buf->buf);
653 msg = strchr(refname, ' ');
654 if (msg) {
655 struct strbuf msg_buf = STRBUF_INIT;
656 const char *end;
658 *msg++ = '\0';
659 if (!unquote_c_style(&msg_buf, msg, &end))
660 msg = strbuf_detach(&msg_buf, NULL);
661 else
662 msg = xstrdup(msg);
663 strbuf_release(&msg_buf);
665 if (!strcmp(msg, "no match")) {
666 status = REF_STATUS_NONE;
667 free(msg);
668 msg = NULL;
670 else if (!strcmp(msg, "up to date")) {
671 status = REF_STATUS_UPTODATE;
672 free(msg);
673 msg = NULL;
675 else if (!strcmp(msg, "non-fast forward")) {
676 status = REF_STATUS_REJECT_NONFASTFORWARD;
677 free(msg);
678 msg = NULL;
680 else if (!strcmp(msg, "already exists")) {
681 status = REF_STATUS_REJECT_ALREADY_EXISTS;
682 free(msg);
683 msg = NULL;
685 else if (!strcmp(msg, "fetch first")) {
686 status = REF_STATUS_REJECT_FETCH_FIRST;
687 free(msg);
688 msg = NULL;
690 else if (!strcmp(msg, "needs force")) {
691 status = REF_STATUS_REJECT_NEEDS_FORCE;
692 free(msg);
693 msg = NULL;
695 else if (!strcmp(msg, "stale info")) {
696 status = REF_STATUS_REJECT_STALE;
697 free(msg);
698 msg = NULL;
700 else if (!strcmp(msg, "forced update")) {
701 forced = 1;
702 free(msg);
703 msg = NULL;
707 if (*ref)
708 *ref = find_ref_by_name(*ref, refname);
709 if (!*ref)
710 *ref = find_ref_by_name(remote_refs, refname);
711 if (!*ref) {
712 warning("helper reported unexpected status of %s", refname);
713 return 1;
716 if ((*ref)->status != REF_STATUS_NONE) {
718 * Earlier, the ref was marked not to be pushed, so ignore the ref
719 * status reported by the remote helper if the latter is 'no match'.
721 if (status == REF_STATUS_NONE)
722 return 1;
725 (*ref)->status = status;
726 (*ref)->forced_update |= forced;
727 (*ref)->remote_status = msg;
728 return !(status == REF_STATUS_OK);
731 static int push_update_refs_status(struct helper_data *data,
732 struct ref *remote_refs,
733 int flags)
735 struct strbuf buf = STRBUF_INIT;
736 struct ref *ref = remote_refs;
737 int ret = 0;
739 for (;;) {
740 char *private;
742 if (recvline(data, &buf)) {
743 ret = 1;
744 break;
747 if (!buf.len)
748 break;
750 if (push_update_ref_status(&buf, &ref, remote_refs))
751 continue;
753 if (flags & TRANSPORT_PUSH_DRY_RUN || !data->refspecs || data->no_private_update)
754 continue;
756 /* propagate back the update to the remote namespace */
757 private = apply_refspecs(data->refspecs, data->refspec_nr, ref->name);
758 if (!private)
759 continue;
760 update_ref("update by helper", private, ref->new_sha1, NULL, 0, 0);
761 free(private);
763 strbuf_release(&buf);
764 return ret;
767 static int push_refs_with_push(struct transport *transport,
768 struct ref *remote_refs, int flags)
770 int force_all = flags & TRANSPORT_PUSH_FORCE;
771 int mirror = flags & TRANSPORT_PUSH_MIRROR;
772 struct helper_data *data = transport->data;
773 struct strbuf buf = STRBUF_INIT;
774 struct ref *ref;
775 struct string_list cas_options = STRING_LIST_INIT_DUP;
776 struct string_list_item *cas_option;
778 get_helper(transport);
779 if (!data->push)
780 return 1;
782 for (ref = remote_refs; ref; ref = ref->next) {
783 if (!ref->peer_ref && !mirror)
784 continue;
786 /* Check for statuses set by set_ref_status_for_push() */
787 switch (ref->status) {
788 case REF_STATUS_REJECT_NONFASTFORWARD:
789 case REF_STATUS_REJECT_STALE:
790 case REF_STATUS_REJECT_ALREADY_EXISTS:
791 case REF_STATUS_UPTODATE:
792 continue;
793 default:
794 ; /* do nothing */
797 if (force_all)
798 ref->force = 1;
800 strbuf_addstr(&buf, "push ");
801 if (!ref->deletion) {
802 if (ref->force)
803 strbuf_addch(&buf, '+');
804 if (ref->peer_ref)
805 strbuf_addstr(&buf, ref->peer_ref->name);
806 else
807 strbuf_addstr(&buf, sha1_to_hex(ref->new_sha1));
809 strbuf_addch(&buf, ':');
810 strbuf_addstr(&buf, ref->name);
811 strbuf_addch(&buf, '\n');
814 * The "--force-with-lease" options without explicit
815 * values to expect have already been expanded into
816 * the ref->old_sha1_expect[] field; we can ignore
817 * transport->smart_options->cas altogether and instead
818 * can enumerate them from the refs.
820 if (ref->expect_old_sha1) {
821 struct strbuf cas = STRBUF_INIT;
822 strbuf_addf(&cas, "%s:%s",
823 ref->name, sha1_to_hex(ref->old_sha1_expect));
824 string_list_append(&cas_options, strbuf_detach(&cas, NULL));
827 if (buf.len == 0) {
828 string_list_clear(&cas_options, 0);
829 return 0;
832 standard_options(transport);
833 for_each_string_list_item(cas_option, &cas_options)
834 set_helper_option(transport, "cas", cas_option->string);
836 if (flags & TRANSPORT_PUSH_DRY_RUN) {
837 if (set_helper_option(transport, "dry-run", "true") != 0)
838 die("helper %s does not support dry-run", data->name);
841 strbuf_addch(&buf, '\n');
842 sendline(data, &buf);
843 strbuf_release(&buf);
845 return push_update_refs_status(data, remote_refs, flags);
848 static int push_refs_with_export(struct transport *transport,
849 struct ref *remote_refs, int flags)
851 struct ref *ref;
852 struct child_process *helper, exporter;
853 struct helper_data *data = transport->data;
854 struct string_list revlist_args = STRING_LIST_INIT_DUP;
855 struct strbuf buf = STRBUF_INIT;
857 if (!data->refspecs)
858 die("remote-helper doesn't support push; refspec needed");
860 if (flags & TRANSPORT_PUSH_DRY_RUN) {
861 if (set_helper_option(transport, "dry-run", "true") != 0)
862 die("helper %s does not support dry-run", data->name);
865 if (flags & TRANSPORT_PUSH_FORCE) {
866 if (set_helper_option(transport, "force", "true") != 0)
867 warning("helper %s does not support 'force'", data->name);
870 helper = get_helper(transport);
872 write_constant(helper->in, "export\n");
874 for (ref = remote_refs; ref; ref = ref->next) {
875 char *private;
876 unsigned char sha1[20];
878 private = apply_refspecs(data->refspecs, data->refspec_nr, ref->name);
879 if (private && !get_sha1(private, sha1)) {
880 strbuf_addf(&buf, "^%s", private);
881 string_list_append(&revlist_args, strbuf_detach(&buf, NULL));
882 hashcpy(ref->old_sha1, sha1);
884 free(private);
886 if (ref->peer_ref) {
887 if (strcmp(ref->name, ref->peer_ref->name)) {
888 if (!ref->deletion) {
889 const char *name;
890 int flag;
892 /* Follow symbolic refs (mainly for HEAD). */
893 name = resolve_ref_unsafe(ref->peer_ref->name, sha1, 1, &flag);
894 if (!name || !(flag & REF_ISSYMREF))
895 name = ref->peer_ref->name;
897 strbuf_addf(&buf, "%s:%s", name, ref->name);
898 } else
899 strbuf_addf(&buf, ":%s", ref->name);
901 string_list_append(&revlist_args, "--refspec");
902 string_list_append(&revlist_args, buf.buf);
903 strbuf_release(&buf);
905 if (!ref->deletion)
906 string_list_append(&revlist_args, ref->peer_ref->name);
910 if (get_exporter(transport, &exporter, &revlist_args))
911 die("Couldn't run fast-export");
913 string_list_clear(&revlist_args, 1);
915 if (finish_command(&exporter))
916 die("Error while running fast-export");
917 if (push_update_refs_status(data, remote_refs, flags))
918 return 1;
920 if (data->export_marks) {
921 strbuf_addf(&buf, "%s.tmp", data->export_marks);
922 rename(buf.buf, data->export_marks);
923 strbuf_release(&buf);
926 return 0;
929 static int push_refs(struct transport *transport,
930 struct ref *remote_refs, int flags)
932 struct helper_data *data = transport->data;
934 if (process_connect(transport, 1)) {
935 do_take_over(transport);
936 return transport->push_refs(transport, remote_refs, flags);
939 if (!remote_refs) {
940 fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
941 "Perhaps you should specify a branch such as 'master'.\n");
942 return 0;
945 if (data->push)
946 return push_refs_with_push(transport, remote_refs, flags);
948 if (data->export)
949 return push_refs_with_export(transport, remote_refs, flags);
951 return -1;
955 static int has_attribute(const char *attrs, const char *attr) {
956 int len;
957 if (!attrs)
958 return 0;
960 len = strlen(attr);
961 for (;;) {
962 const char *space = strchrnul(attrs, ' ');
963 if (len == space - attrs && !strncmp(attrs, attr, len))
964 return 1;
965 if (!*space)
966 return 0;
967 attrs = space + 1;
971 static struct ref *get_refs_list(struct transport *transport, int for_push)
973 struct helper_data *data = transport->data;
974 struct child_process *helper;
975 struct ref *ret = NULL;
976 struct ref **tail = &ret;
977 struct ref *posn;
978 struct strbuf buf = STRBUF_INIT;
980 helper = get_helper(transport);
982 if (process_connect(transport, for_push)) {
983 do_take_over(transport);
984 return transport->get_refs_list(transport, for_push);
987 if (data->push && for_push)
988 write_str_in_full(helper->in, "list for-push\n");
989 else
990 write_str_in_full(helper->in, "list\n");
992 while (1) {
993 char *eov, *eon;
994 if (recvline(data, &buf))
995 exit(128);
997 if (!*buf.buf)
998 break;
1000 eov = strchr(buf.buf, ' ');
1001 if (!eov)
1002 die("Malformed response in ref list: %s", buf.buf);
1003 eon = strchr(eov + 1, ' ');
1004 *eov = '\0';
1005 if (eon)
1006 *eon = '\0';
1007 *tail = alloc_ref(eov + 1);
1008 if (buf.buf[0] == '@')
1009 (*tail)->symref = xstrdup(buf.buf + 1);
1010 else if (buf.buf[0] != '?')
1011 get_sha1_hex(buf.buf, (*tail)->old_sha1);
1012 if (eon) {
1013 if (has_attribute(eon + 1, "unchanged")) {
1014 (*tail)->status |= REF_STATUS_UPTODATE;
1015 read_ref((*tail)->name, (*tail)->old_sha1);
1018 tail = &((*tail)->next);
1020 if (debug)
1021 fprintf(stderr, "Debug: Read ref listing.\n");
1022 strbuf_release(&buf);
1024 for (posn = ret; posn; posn = posn->next)
1025 resolve_remote_symref(posn, ret);
1027 return ret;
1030 int transport_helper_init(struct transport *transport, const char *name)
1032 struct helper_data *data = xcalloc(1, sizeof(*data));
1033 data->name = name;
1035 if (getenv("GIT_TRANSPORT_HELPER_DEBUG"))
1036 debug = 1;
1038 transport->data = data;
1039 transport->set_option = set_helper_option;
1040 transport->get_refs_list = get_refs_list;
1041 transport->fetch = fetch;
1042 transport->push_refs = push_refs;
1043 transport->disconnect = release_helper;
1044 transport->connect = connect_helper;
1045 transport->smart_options = &(data->transport_options);
1046 return 0;
1050 * Linux pipes can buffer 65536 bytes at once (and most platforms can
1051 * buffer less), so attempt reads and writes with up to that size.
1053 #define BUFFERSIZE 65536
1054 /* This should be enough to hold debugging message. */
1055 #define PBUFFERSIZE 8192
1057 /* Print bidirectional transfer loop debug message. */
1058 __attribute__((format (printf, 1, 2)))
1059 static void transfer_debug(const char *fmt, ...)
1061 va_list args;
1062 char msgbuf[PBUFFERSIZE];
1063 static int debug_enabled = -1;
1065 if (debug_enabled < 0)
1066 debug_enabled = getenv("GIT_TRANSLOOP_DEBUG") ? 1 : 0;
1067 if (!debug_enabled)
1068 return;
1070 va_start(args, fmt);
1071 vsnprintf(msgbuf, PBUFFERSIZE, fmt, args);
1072 va_end(args);
1073 fprintf(stderr, "Transfer loop debugging: %s\n", msgbuf);
1076 /* Stream state: More data may be coming in this direction. */
1077 #define SSTATE_TRANSFERING 0
1079 * Stream state: No more data coming in this direction, flushing rest of
1080 * data.
1082 #define SSTATE_FLUSHING 1
1083 /* Stream state: Transfer in this direction finished. */
1084 #define SSTATE_FINISHED 2
1086 #define STATE_NEEDS_READING(state) ((state) <= SSTATE_TRANSFERING)
1087 #define STATE_NEEDS_WRITING(state) ((state) <= SSTATE_FLUSHING)
1088 #define STATE_NEEDS_CLOSING(state) ((state) == SSTATE_FLUSHING)
1090 /* Unidirectional transfer. */
1091 struct unidirectional_transfer {
1092 /* Source */
1093 int src;
1094 /* Destination */
1095 int dest;
1096 /* Is source socket? */
1097 int src_is_sock;
1098 /* Is destination socket? */
1099 int dest_is_sock;
1100 /* Transfer state (TRANSFERRING/FLUSHING/FINISHED) */
1101 int state;
1102 /* Buffer. */
1103 char buf[BUFFERSIZE];
1104 /* Buffer used. */
1105 size_t bufuse;
1106 /* Name of source. */
1107 const char *src_name;
1108 /* Name of destination. */
1109 const char *dest_name;
1112 /* Closes the target (for writing) if transfer has finished. */
1113 static void udt_close_if_finished(struct unidirectional_transfer *t)
1115 if (STATE_NEEDS_CLOSING(t->state) && !t->bufuse) {
1116 t->state = SSTATE_FINISHED;
1117 if (t->dest_is_sock)
1118 shutdown(t->dest, SHUT_WR);
1119 else
1120 close(t->dest);
1121 transfer_debug("Closed %s.", t->dest_name);
1126 * Tries to read read data from source into buffer. If buffer is full,
1127 * no data is read. Returns 0 on success, -1 on error.
1129 static int udt_do_read(struct unidirectional_transfer *t)
1131 ssize_t bytes;
1133 if (t->bufuse == BUFFERSIZE)
1134 return 0; /* No space for more. */
1136 transfer_debug("%s is readable", t->src_name);
1137 bytes = read(t->src, t->buf + t->bufuse, BUFFERSIZE - t->bufuse);
1138 if (bytes < 0 && errno != EWOULDBLOCK && errno != EAGAIN &&
1139 errno != EINTR) {
1140 error("read(%s) failed: %s", t->src_name, strerror(errno));
1141 return -1;
1142 } else if (bytes == 0) {
1143 transfer_debug("%s EOF (with %i bytes in buffer)",
1144 t->src_name, (int)t->bufuse);
1145 t->state = SSTATE_FLUSHING;
1146 } else if (bytes > 0) {
1147 t->bufuse += bytes;
1148 transfer_debug("Read %i bytes from %s (buffer now at %i)",
1149 (int)bytes, t->src_name, (int)t->bufuse);
1151 return 0;
1154 /* Tries to write data from buffer into destination. If buffer is empty,
1155 * no data is written. Returns 0 on success, -1 on error.
1157 static int udt_do_write(struct unidirectional_transfer *t)
1159 ssize_t bytes;
1161 if (t->bufuse == 0)
1162 return 0; /* Nothing to write. */
1164 transfer_debug("%s is writable", t->dest_name);
1165 bytes = xwrite(t->dest, t->buf, t->bufuse);
1166 if (bytes < 0 && errno != EWOULDBLOCK) {
1167 error("write(%s) failed: %s", t->dest_name, strerror(errno));
1168 return -1;
1169 } else if (bytes > 0) {
1170 t->bufuse -= bytes;
1171 if (t->bufuse)
1172 memmove(t->buf, t->buf + bytes, t->bufuse);
1173 transfer_debug("Wrote %i bytes to %s (buffer now at %i)",
1174 (int)bytes, t->dest_name, (int)t->bufuse);
1176 return 0;
1180 /* State of bidirectional transfer loop. */
1181 struct bidirectional_transfer_state {
1182 /* Direction from program to git. */
1183 struct unidirectional_transfer ptg;
1184 /* Direction from git to program. */
1185 struct unidirectional_transfer gtp;
1188 static void *udt_copy_task_routine(void *udt)
1190 struct unidirectional_transfer *t = (struct unidirectional_transfer *)udt;
1191 while (t->state != SSTATE_FINISHED) {
1192 if (STATE_NEEDS_READING(t->state))
1193 if (udt_do_read(t))
1194 return NULL;
1195 if (STATE_NEEDS_WRITING(t->state))
1196 if (udt_do_write(t))
1197 return NULL;
1198 if (STATE_NEEDS_CLOSING(t->state))
1199 udt_close_if_finished(t);
1201 return udt; /* Just some non-NULL value. */
1204 #ifndef NO_PTHREADS
1207 * Join thread, with appropriate errors on failure. Name is name for the
1208 * thread (for error messages). Returns 0 on success, 1 on failure.
1210 static int tloop_join(pthread_t thread, const char *name)
1212 int err;
1213 void *tret;
1214 err = pthread_join(thread, &tret);
1215 if (!tret) {
1216 error("%s thread failed", name);
1217 return 1;
1219 if (err) {
1220 error("%s thread failed to join: %s", name, strerror(err));
1221 return 1;
1223 return 0;
1227 * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1228 * -1 on failure.
1230 static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1232 pthread_t gtp_thread;
1233 pthread_t ptg_thread;
1234 int err;
1235 int ret = 0;
1236 err = pthread_create(&gtp_thread, NULL, udt_copy_task_routine,
1237 &s->gtp);
1238 if (err)
1239 die("Can't start thread for copying data: %s", strerror(err));
1240 err = pthread_create(&ptg_thread, NULL, udt_copy_task_routine,
1241 &s->ptg);
1242 if (err)
1243 die("Can't start thread for copying data: %s", strerror(err));
1245 ret |= tloop_join(gtp_thread, "Git to program copy");
1246 ret |= tloop_join(ptg_thread, "Program to git copy");
1247 return ret;
1249 #else
1251 /* Close the source and target (for writing) for transfer. */
1252 static void udt_kill_transfer(struct unidirectional_transfer *t)
1254 t->state = SSTATE_FINISHED;
1256 * Socket read end left open isn't a disaster if nobody
1257 * attempts to read from it (mingw compat headers do not
1258 * have SHUT_RD)...
1260 * We can't fully close the socket since otherwise gtp
1261 * task would first close the socket it sends data to
1262 * while closing the ptg file descriptors.
1264 if (!t->src_is_sock)
1265 close(t->src);
1266 if (t->dest_is_sock)
1267 shutdown(t->dest, SHUT_WR);
1268 else
1269 close(t->dest);
1273 * Join process, with appropriate errors on failure. Name is name for the
1274 * process (for error messages). Returns 0 on success, 1 on failure.
1276 static int tloop_join(pid_t pid, const char *name)
1278 int tret;
1279 if (waitpid(pid, &tret, 0) < 0) {
1280 error("%s process failed to wait: %s", name, strerror(errno));
1281 return 1;
1283 if (!WIFEXITED(tret) || WEXITSTATUS(tret)) {
1284 error("%s process failed", name);
1285 return 1;
1287 return 0;
1291 * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1292 * -1 on failure.
1294 static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1296 pid_t pid1, pid2;
1297 int ret = 0;
1299 /* Fork thread #1: git to program. */
1300 pid1 = fork();
1301 if (pid1 < 0)
1302 die_errno("Can't start thread for copying data");
1303 else if (pid1 == 0) {
1304 udt_kill_transfer(&s->ptg);
1305 exit(udt_copy_task_routine(&s->gtp) ? 0 : 1);
1308 /* Fork thread #2: program to git. */
1309 pid2 = fork();
1310 if (pid2 < 0)
1311 die_errno("Can't start thread for copying data");
1312 else if (pid2 == 0) {
1313 udt_kill_transfer(&s->gtp);
1314 exit(udt_copy_task_routine(&s->ptg) ? 0 : 1);
1318 * Close both streams in parent as to not interfere with
1319 * end of file detection and wait for both tasks to finish.
1321 udt_kill_transfer(&s->gtp);
1322 udt_kill_transfer(&s->ptg);
1323 ret |= tloop_join(pid1, "Git to program copy");
1324 ret |= tloop_join(pid2, "Program to git copy");
1325 return ret;
1327 #endif
1330 * Copies data from stdin to output and from input to stdout simultaneously.
1331 * Additionally filtering through given filter. If filter is NULL, uses
1332 * identity filter.
1334 int bidirectional_transfer_loop(int input, int output)
1336 struct bidirectional_transfer_state state;
1338 /* Fill the state fields. */
1339 state.ptg.src = input;
1340 state.ptg.dest = 1;
1341 state.ptg.src_is_sock = (input == output);
1342 state.ptg.dest_is_sock = 0;
1343 state.ptg.state = SSTATE_TRANSFERING;
1344 state.ptg.bufuse = 0;
1345 state.ptg.src_name = "remote input";
1346 state.ptg.dest_name = "stdout";
1348 state.gtp.src = 0;
1349 state.gtp.dest = output;
1350 state.gtp.src_is_sock = 0;
1351 state.gtp.dest_is_sock = (input == output);
1352 state.gtp.state = SSTATE_TRANSFERING;
1353 state.gtp.bufuse = 0;
1354 state.gtp.src_name = "stdin";
1355 state.gtp.dest_name = "remote output";
1357 return tloop_spawnwait_tasks(&state);