transport-helper: update refspec documentation
[git/git.git] / transport-helper.c
CommitLineData
6eb996b5
DB
1#include "cache.h"
2#include "transport.h"
ae4efe19 3#include "quote.h"
6eb996b5
DB
4#include "run-command.h"
5#include "commit.h"
6#include "diff.h"
7#include "revision.h"
ef08ef9e 8#include "quote.h"
72ff8943 9#include "remote.h"
73b49a75 10#include "string-list.h"
7851b1e6 11#include "thread-utils.h"
c34fe630 12#include "sigchain.h"
bfc366d9 13#include "argv-array.h"
7851b1e6 14
bf3c523c
IL
15static int debug;
16
9cba13ca 17struct helper_data {
6eb996b5
DB
18 const char *name;
19 struct child_process *helper;
292ce46b 20 FILE *out;
ef08ef9e 21 unsigned fetch : 1,
a24a32dd 22 import : 1,
bfc366d9 23 bidi_import : 1,
73b49a75 24 export : 1,
ae4efe19 25 option : 1,
fa8c097c
IL
26 push : 1,
27 connect : 1,
28 no_disconnect_req : 1;
a515ebe9
SR
29 char *export_marks;
30 char *import_marks;
72ff8943
DB
31 /* These go from remote name (as in "list") to private name */
32 struct refspec *refspecs;
33 int refspec_nr;
61b075bd
IL
34 /* Transport options for fetch-pack/send-pack (should one of
35 * those be invoked).
36 */
37 struct git_transport_options transport_options;
6eb996b5
DB
38};
39
bf3c523c
IL
40static void sendline(struct helper_data *helper, struct strbuf *buffer)
41{
42 if (debug)
43 fprintf(stderr, "Debug: Remote helper: -> %s", buffer->buf);
44 if (write_in_full(helper->helper->in, buffer->buf, buffer->len)
45 != buffer->len)
46 die_errno("Full write to remote helper failed");
47}
48
c096955c 49static int recvline_fh(FILE *helper, struct strbuf *buffer, const char *name)
bf3c523c
IL
50{
51 strbuf_reset(buffer);
52 if (debug)
53 fprintf(stderr, "Debug: Remote helper: Waiting...\n");
fa8c097c 54 if (strbuf_getline(buffer, helper, '\n') == EOF) {
bf3c523c
IL
55 if (debug)
56 fprintf(stderr, "Debug: Remote helper quit.\n");
c096955c 57 die("Reading from helper 'git-remote-%s' failed", name);
bf3c523c
IL
58 }
59
60 if (debug)
61 fprintf(stderr, "Debug: Remote helper: <- %s\n", buffer->buf);
62 return 0;
63}
64
fa8c097c
IL
65static int recvline(struct helper_data *helper, struct strbuf *buffer)
66{
c096955c 67 return recvline_fh(helper->out, buffer, helper->name);
fa8c097c
IL
68}
69
bf3c523c
IL
70static void xchgline(struct helper_data *helper, struct strbuf *buffer)
71{
72 sendline(helper, buffer);
73 recvline(helper, buffer);
74}
75
76static void write_constant(int fd, const char *str)
77{
78 if (debug)
79 fprintf(stderr, "Debug: Remote helper: -> %s", str);
80 if (write_in_full(fd, str, strlen(str)) != strlen(str))
81 die_errno("Full write to remote helper failed");
82}
83
c2e86add 84static const char *remove_ext_force(const char *url)
25d5cc48
IL
85{
86 if (url) {
87 const char *colon = strchr(url, ':');
88 if (colon && colon[1] == ':')
89 return colon + 2;
90 }
91 return url;
92}
93
fa8c097c
IL
94static void do_take_over(struct transport *transport)
95{
96 struct helper_data *data;
97 data = (struct helper_data *)transport->data;
98 transport_take_over(transport, data->helper);
99 fclose(data->out);
100 free(data);
101}
102
6eb996b5
DB
103static struct child_process *get_helper(struct transport *transport)
104{
105 struct helper_data *data = transport->data;
bfc366d9 106 struct argv_array argv = ARGV_ARRAY_INIT;
6eb996b5
DB
107 struct strbuf buf = STRBUF_INIT;
108 struct child_process *helper;
72ff8943
DB
109 const char **refspecs = NULL;
110 int refspec_nr = 0;
111 int refspec_alloc = 0;
61b075bd 112 int duped;
6b02de3b 113 int code;
e1735872
DI
114 char git_dir_buf[sizeof(GIT_DIR_ENVIRONMENT) + PATH_MAX + 1];
115 const char *helper_env[] = {
116 git_dir_buf,
117 NULL
118 };
119
6eb996b5
DB
120
121 if (data->helper)
122 return data->helper;
123
124 helper = xcalloc(1, sizeof(*helper));
125 helper->in = -1;
126 helper->out = -1;
127 helper->err = 0;
bfc366d9
FA
128 argv_array_pushf(&argv, "git-remote-%s", data->name);
129 argv_array_push(&argv, transport->remote->name);
130 argv_array_push(&argv, remove_ext_force(transport->url));
131 helper->argv = argv_array_detach(&argv, NULL);
6b02de3b
IL
132 helper->git_cmd = 0;
133 helper->silent_exec_failure = 1;
e1735872
DI
134
135 snprintf(git_dir_buf, sizeof(git_dir_buf), "%s=%s", GIT_DIR_ENVIRONMENT, get_git_dir());
136 helper->env = helper_env;
137
6b02de3b
IL
138 code = start_command(helper);
139 if (code < 0 && errno == ENOENT)
140 die("Unable to find remote helper for '%s'", data->name);
141 else if (code != 0)
142 exit(code);
143
6eb996b5 144 data->helper = helper;
fa8c097c 145 data->no_disconnect_req = 0;
6eb996b5 146
61b075bd
IL
147 /*
148 * Open the output as FILE* so strbuf_getline() can be used.
149 * Do this with duped fd because fclose() will close the fd,
150 * and stuff like taking over will require the fd to remain.
61b075bd
IL
151 */
152 duped = dup(helper->out);
153 if (duped < 0)
154 die_errno("Can't dup helper output fd");
155 data->out = xfdopen(duped, "r");
156
bf3c523c 157 write_constant(helper->in, "capabilities\n");
2d14d65c 158
6eb996b5 159 while (1) {
28ed5b35
IL
160 const char *capname;
161 int mandatory = 0;
bf3c523c 162 recvline(data, &buf);
6eb996b5
DB
163
164 if (!*buf.buf)
165 break;
28ed5b35
IL
166
167 if (*buf.buf == '*') {
168 capname = buf.buf + 1;
169 mandatory = 1;
170 } else
171 capname = buf.buf;
172
bf3c523c 173 if (debug)
28ed5b35
IL
174 fprintf(stderr, "Debug: Got cap %s\n", capname);
175 if (!strcmp(capname, "fetch"))
6eb996b5 176 data->fetch = 1;
28ed5b35 177 else if (!strcmp(capname, "option"))
ef08ef9e 178 data->option = 1;
28ed5b35 179 else if (!strcmp(capname, "push"))
ae4efe19 180 data->push = 1;
28ed5b35 181 else if (!strcmp(capname, "import"))
e65e91ed 182 data->import = 1;
bfc366d9
FA
183 else if (!strcmp(capname, "bidi-import"))
184 data->bidi_import = 1;
73b49a75
SR
185 else if (!strcmp(capname, "export"))
186 data->export = 1;
28ed5b35 187 else if (!data->refspecs && !prefixcmp(capname, "refspec ")) {
72ff8943
DB
188 ALLOC_GROW(refspecs,
189 refspec_nr + 1,
190 refspec_alloc);
c28cce55 191 refspecs[refspec_nr++] = xstrdup(capname + strlen("refspec "));
fa8c097c
IL
192 } else if (!strcmp(capname, "connect")) {
193 data->connect = 1;
a515ebe9
SR
194 } else if (!prefixcmp(capname, "export-marks ")) {
195 struct strbuf arg = STRBUF_INIT;
196 strbuf_addstr(&arg, "--export-marks=");
197 strbuf_addstr(&arg, capname + strlen("export-marks "));
198 data->export_marks = strbuf_detach(&arg, NULL);
199 } else if (!prefixcmp(capname, "import-marks")) {
200 struct strbuf arg = STRBUF_INIT;
201 strbuf_addstr(&arg, "--import-marks=");
202 strbuf_addstr(&arg, capname + strlen("import-marks "));
203 data->import_marks = strbuf_detach(&arg, NULL);
28ed5b35 204 } else if (mandatory) {
9517e6b8 205 die("Unknown mandatory capability %s. This remote "
82247e9b 206 "helper probably needs newer version of Git.",
28ed5b35 207 capname);
72ff8943
DB
208 }
209 }
210 if (refspecs) {
211 int i;
212 data->refspec_nr = refspec_nr;
213 data->refspecs = parse_fetch_refspec(refspec_nr, refspecs);
214 for (i = 0; i < refspec_nr; i++) {
215 free((char *)refspecs[i]);
216 }
217 free(refspecs);
6eb996b5 218 }
b962dbdc 219 strbuf_release(&buf);
bf3c523c
IL
220 if (debug)
221 fprintf(stderr, "Debug: Capabilities complete.\n");
6eb996b5
DB
222 return data->helper;
223}
224
225static int disconnect_helper(struct transport *transport)
226{
227 struct helper_data *data = transport->data;
cc567322 228 int res = 0;
bf3c523c 229
6eb996b5 230 if (data->helper) {
bf3c523c
IL
231 if (debug)
232 fprintf(stderr, "Debug: Disconnecting.\n");
fa8c097c 233 if (!data->no_disconnect_req) {
c34fe630
JK
234 /*
235 * Ignore write errors; there's nothing we can do,
236 * since we're about to close the pipe anyway. And the
237 * most likely error is EPIPE due to the helper dying
238 * to report an error itself.
239 */
240 sigchain_push(SIGPIPE, SIG_IGN);
241 xwrite(data->helper->in, "\n", 1);
242 sigchain_pop(SIGPIPE);
fa8c097c 243 }
6eb996b5 244 close(data->helper->in);
61b075bd 245 close(data->helper->out);
292ce46b 246 fclose(data->out);
cc567322 247 res = finish_command(data->helper);
bfc366d9 248 argv_array_free_detached(data->helper->argv);
6eb996b5
DB
249 free(data->helper);
250 data->helper = NULL;
251 }
cc567322 252 return res;
6eb996b5
DB
253}
254
ef08ef9e
SP
255static const char *unsupported_options[] = {
256 TRANS_OPT_UPLOADPACK,
257 TRANS_OPT_RECEIVEPACK,
258 TRANS_OPT_THIN,
259 TRANS_OPT_KEEP
260 };
261static const char *boolean_options[] = {
262 TRANS_OPT_THIN,
263 TRANS_OPT_KEEP,
264 TRANS_OPT_FOLLOWTAGS
265 };
266
267static int set_helper_option(struct transport *transport,
268 const char *name, const char *value)
269{
270 struct helper_data *data = transport->data;
ef08ef9e
SP
271 struct strbuf buf = STRBUF_INIT;
272 int i, ret, is_bool = 0;
273
bf3c523c
IL
274 get_helper(transport);
275
ef08ef9e
SP
276 if (!data->option)
277 return 1;
278
279 for (i = 0; i < ARRAY_SIZE(unsupported_options); i++) {
280 if (!strcmp(name, unsupported_options[i]))
281 return 1;
282 }
283
284 for (i = 0; i < ARRAY_SIZE(boolean_options); i++) {
285 if (!strcmp(name, boolean_options[i])) {
286 is_bool = 1;
287 break;
288 }
289 }
290
291 strbuf_addf(&buf, "option %s ", name);
292 if (is_bool)
293 strbuf_addstr(&buf, value ? "true" : "false");
294 else
295 quote_c_style(value, &buf, NULL, 0);
296 strbuf_addch(&buf, '\n');
297
bf3c523c 298 xchgline(data, &buf);
ef08ef9e
SP
299
300 if (!strcmp(buf.buf, "ok"))
301 ret = 0;
302 else if (!prefixcmp(buf.buf, "error")) {
303 ret = -1;
304 } else if (!strcmp(buf.buf, "unsupported"))
305 ret = 1;
306 else {
307 warning("%s unexpectedly said: '%s'", data->name, buf.buf);
308 ret = 1;
309 }
310 strbuf_release(&buf);
311 return ret;
312}
313
314static void standard_options(struct transport *t)
315{
316 char buf[16];
317 int n;
318 int v = t->verbose;
ef08ef9e 319
d01b3c02 320 set_helper_option(t, "progress", t->progress ? "true" : "false");
ef08ef9e
SP
321
322 n = snprintf(buf, sizeof(buf), "%d", v + 1);
323 if (n >= sizeof(buf))
324 die("impossibly large verbosity value");
325 set_helper_option(t, "verbosity", buf);
326}
327
f2a37151
DB
328static int release_helper(struct transport *transport)
329{
cc567322 330 int res = 0;
72ff8943
DB
331 struct helper_data *data = transport->data;
332 free_refspec(data->refspec_nr, data->refspecs);
333 data->refspecs = NULL;
cc567322 334 res = disconnect_helper(transport);
f2a37151 335 free(transport->data);
cc567322 336 return res;
f2a37151
DB
337}
338
6eb996b5 339static int fetch_with_fetch(struct transport *transport,
37148311 340 int nr_heads, struct ref **to_fetch)
6eb996b5 341{
292ce46b 342 struct helper_data *data = transport->data;
6eb996b5
DB
343 int i;
344 struct strbuf buf = STRBUF_INIT;
345
ef08ef9e
SP
346 standard_options(transport);
347
6eb996b5 348 for (i = 0; i < nr_heads; i++) {
1088261f 349 const struct ref *posn = to_fetch[i];
6eb996b5
DB
350 if (posn->status & REF_STATUS_UPTODATE)
351 continue;
2d14d65c
DB
352
353 strbuf_addf(&buf, "fetch %s %s\n",
354 sha1_to_hex(posn->old_sha1), posn->name);
292ce46b 355 }
2d14d65c 356
292ce46b 357 strbuf_addch(&buf, '\n');
bf3c523c 358 sendline(data, &buf);
292ce46b
SP
359
360 while (1) {
bf3c523c 361 recvline(data, &buf);
292ce46b
SP
362
363 if (!prefixcmp(buf.buf, "lock ")) {
364 const char *name = buf.buf + 5;
365 if (transport->pack_lockfile)
366 warning("%s also locked %s", data->name, name);
367 else
368 transport->pack_lockfile = xstrdup(name);
369 }
370 else if (!buf.len)
371 break;
372 else
373 warning("%s unexpectedly said: '%s'", data->name, buf.buf);
6eb996b5 374 }
292ce46b 375 strbuf_release(&buf);
6eb996b5
DB
376 return 0;
377}
378
e65e91ed
DB
379static int get_importer(struct transport *transport, struct child_process *fastimport)
380{
381 struct child_process *helper = get_helper(transport);
bfc366d9
FA
382 struct helper_data *data = transport->data;
383 struct argv_array argv = ARGV_ARRAY_INIT;
384 int cat_blob_fd, code;
e65e91ed
DB
385 memset(fastimport, 0, sizeof(*fastimport));
386 fastimport->in = helper->out;
bfc366d9 387 argv_array_push(&argv, "fast-import");
19ba02af 388 argv_array_push(&argv, debug ? "--stats" : "--quiet");
e65e91ed 389
bfc366d9
FA
390 if (data->bidi_import) {
391 cat_blob_fd = xdup(helper->in);
392 argv_array_pushf(&argv, "--cat-blob-fd=%d", cat_blob_fd);
393 }
394 fastimport->argv = argv.argv;
e65e91ed 395 fastimport->git_cmd = 1;
bfc366d9
FA
396
397 code = start_command(fastimport);
398 return code;
e65e91ed
DB
399}
400
73b49a75
SR
401static int get_exporter(struct transport *transport,
402 struct child_process *fastexport,
73b49a75
SR
403 struct string_list *revlist_args)
404{
a515ebe9 405 struct helper_data *data = transport->data;
73b49a75
SR
406 struct child_process *helper = get_helper(transport);
407 int argc = 0, i;
408 memset(fastexport, 0, sizeof(*fastexport));
409
410 /* we need to duplicate helper->in because we want to use it after
411 * fastexport is done with it. */
412 fastexport->out = dup(helper->in);
1f25c504 413 fastexport->argv = xcalloc(5 + revlist_args->nr, sizeof(*fastexport->argv));
73b49a75 414 fastexport->argv[argc++] = "fast-export";
1f25c504 415 fastexport->argv[argc++] = "--use-done-feature";
a515ebe9
SR
416 if (data->export_marks)
417 fastexport->argv[argc++] = data->export_marks;
418 if (data->import_marks)
419 fastexport->argv[argc++] = data->import_marks;
73b49a75
SR
420
421 for (i = 0; i < revlist_args->nr; i++)
422 fastexport->argv[argc++] = revlist_args->items[i].string;
423
424 fastexport->git_cmd = 1;
425 return start_command(fastexport);
426}
427
e65e91ed
DB
428static int fetch_with_import(struct transport *transport,
429 int nr_heads, struct ref **to_fetch)
430{
431 struct child_process fastimport;
72ff8943 432 struct helper_data *data = transport->data;
e65e91ed
DB
433 int i;
434 struct ref *posn;
435 struct strbuf buf = STRBUF_INIT;
436
bf3c523c
IL
437 get_helper(transport);
438
e65e91ed
DB
439 if (get_importer(transport, &fastimport))
440 die("Couldn't run fast-import");
441
442 for (i = 0; i < nr_heads; i++) {
443 posn = to_fetch[i];
444 if (posn->status & REF_STATUS_UPTODATE)
445 continue;
446
447 strbuf_addf(&buf, "import %s\n", posn->name);
bf3c523c 448 sendline(data, &buf);
e65e91ed
DB
449 strbuf_reset(&buf);
450 }
9504bc9d
SR
451
452 write_constant(data->helper->in, "\n");
bfc366d9
FA
453 /*
454 * remote-helpers that advertise the bidi-import capability are required to
455 * buffer the complete batch of import commands until this newline before
456 * sending data to fast-import.
457 * These helpers read back data from fast-import on their stdin, which could
458 * be mixed with import commands, otherwise.
459 */
9504bc9d 460
cc567322
SR
461 if (finish_command(&fastimport))
462 die("Error while running fast-import");
bfc366d9 463 argv_array_free_detached(fastimport.argv);
e65e91ed 464
dff9d65d
FA
465 /*
466 * The fast-import stream of a remote helper that advertises
467 * the "refspec" capability writes to the refs named after the
468 * right hand side of the first refspec matching each ref we
469 * were fetching.
470 *
471 * (If no "refspec" capability was specified, for historical
7a43c554 472 * reasons we default to the equivalent of *:*.)
dff9d65d
FA
473 *
474 * Store the result in to_fetch[i].old_sha1. Callers such
475 * as "git fetch" can use the value to write feedback to the
476 * terminal, populate FETCH_HEAD, and determine what new value
477 * should be written to peer_ref if the update is a
478 * fast-forward or this is a forced update.
479 */
e65e91ed 480 for (i = 0; i < nr_heads; i++) {
72ff8943 481 char *private;
e65e91ed
DB
482 posn = to_fetch[i];
483 if (posn->status & REF_STATUS_UPTODATE)
484 continue;
72ff8943
DB
485 if (data->refspecs)
486 private = apply_refspecs(data->refspecs, data->refspec_nr, posn->name);
487 else
c28cce55 488 private = xstrdup(posn->name);
d51b720f
MH
489 if (private) {
490 read_ref(private, posn->old_sha1);
491 free(private);
492 }
e65e91ed 493 }
b962dbdc 494 strbuf_release(&buf);
e65e91ed
DB
495 return 0;
496}
497
fa8c097c
IL
498static int process_connect_service(struct transport *transport,
499 const char *name, const char *exec)
500{
501 struct helper_data *data = transport->data;
502 struct strbuf cmdbuf = STRBUF_INIT;
503 struct child_process *helper;
504 int r, duped, ret = 0;
505 FILE *input;
506
507 helper = get_helper(transport);
508
509 /*
510 * Yes, dup the pipe another time, as we need unbuffered version
511 * of input pipe as FILE*. fclose() closes the underlying fd and
512 * stream buffering only can be changed before first I/O operation
513 * on it.
514 */
515 duped = dup(helper->out);
516 if (duped < 0)
517 die_errno("Can't dup helper output fd");
518 input = xfdopen(duped, "r");
519 setvbuf(input, NULL, _IONBF, 0);
520
521 /*
522 * Handle --upload-pack and friends. This is fire and forget...
523 * just warn if it fails.
524 */
525 if (strcmp(name, exec)) {
526 r = set_helper_option(transport, "servpath", exec);
527 if (r > 0)
528 warning("Setting remote service path not supported by protocol.");
529 else if (r < 0)
530 warning("Invalid remote service path.");
531 }
532
533 if (data->connect)
534 strbuf_addf(&cmdbuf, "connect %s\n", name);
535 else
536 goto exit;
537
538 sendline(data, &cmdbuf);
c096955c 539 recvline_fh(input, &cmdbuf, name);
fa8c097c
IL
540 if (!strcmp(cmdbuf.buf, "")) {
541 data->no_disconnect_req = 1;
542 if (debug)
543 fprintf(stderr, "Debug: Smart transport connection "
544 "ready.\n");
545 ret = 1;
546 } else if (!strcmp(cmdbuf.buf, "fallback")) {
547 if (debug)
548 fprintf(stderr, "Debug: Falling back to dumb "
549 "transport.\n");
550 } else
551 die("Unknown response to connect: %s",
552 cmdbuf.buf);
553
554exit:
555 fclose(input);
556 return ret;
557}
558
559static int process_connect(struct transport *transport,
560 int for_push)
561{
562 struct helper_data *data = transport->data;
563 const char *name;
564 const char *exec;
565
566 name = for_push ? "git-receive-pack" : "git-upload-pack";
567 if (for_push)
568 exec = data->transport_options.receivepack;
569 else
570 exec = data->transport_options.uploadpack;
571
572 return process_connect_service(transport, name, exec);
573}
574
b236752a
IL
575static int connect_helper(struct transport *transport, const char *name,
576 const char *exec, int fd[2])
577{
578 struct helper_data *data = transport->data;
579
580 /* Get_helper so connect is inited. */
581 get_helper(transport);
582 if (!data->connect)
583 die("Operation not supported by protocol.");
584
585 if (!process_connect_service(transport, name, exec))
586 die("Can't connect to subservice %s.", name);
587
588 fd[0] = data->helper->out;
589 fd[1] = data->helper->in;
590 return 0;
591}
592
6eb996b5 593static int fetch(struct transport *transport,
37148311 594 int nr_heads, struct ref **to_fetch)
6eb996b5
DB
595{
596 struct helper_data *data = transport->data;
597 int i, count;
598
fa8c097c
IL
599 if (process_connect(transport, 0)) {
600 do_take_over(transport);
601 return transport->fetch(transport, nr_heads, to_fetch);
602 }
603
6eb996b5
DB
604 count = 0;
605 for (i = 0; i < nr_heads; i++)
606 if (!(to_fetch[i]->status & REF_STATUS_UPTODATE))
607 count++;
608
609 if (!count)
610 return 0;
611
612 if (data->fetch)
613 return fetch_with_fetch(transport, nr_heads, to_fetch);
614
e65e91ed
DB
615 if (data->import)
616 return fetch_with_import(transport, nr_heads, to_fetch);
617
6eb996b5
DB
618 return -1;
619}
620
d2e73c6f
SR
621static void push_update_ref_status(struct strbuf *buf,
622 struct ref **ref,
623 struct ref *remote_refs)
624{
625 char *refname, *msg;
626 int status;
627
628 if (!prefixcmp(buf->buf, "ok ")) {
629 status = REF_STATUS_OK;
630 refname = buf->buf + 3;
631 } else if (!prefixcmp(buf->buf, "error ")) {
632 status = REF_STATUS_REMOTE_REJECT;
633 refname = buf->buf + 6;
634 } else
82247e9b 635 die("expected ok/error, helper said '%s'", buf->buf);
d2e73c6f
SR
636
637 msg = strchr(refname, ' ');
638 if (msg) {
639 struct strbuf msg_buf = STRBUF_INIT;
640 const char *end;
641
642 *msg++ = '\0';
643 if (!unquote_c_style(&msg_buf, msg, &end))
644 msg = strbuf_detach(&msg_buf, NULL);
645 else
646 msg = xstrdup(msg);
647 strbuf_release(&msg_buf);
648
649 if (!strcmp(msg, "no match")) {
650 status = REF_STATUS_NONE;
651 free(msg);
652 msg = NULL;
653 }
654 else if (!strcmp(msg, "up to date")) {
655 status = REF_STATUS_UPTODATE;
656 free(msg);
657 msg = NULL;
658 }
659 else if (!strcmp(msg, "non-fast forward")) {
660 status = REF_STATUS_REJECT_NONFASTFORWARD;
661 free(msg);
662 msg = NULL;
663 }
dbfeddb1
CR
664 else if (!strcmp(msg, "already exists")) {
665 status = REF_STATUS_REJECT_ALREADY_EXISTS;
666 free(msg);
667 msg = NULL;
668 }
75e5c0dc
JH
669 else if (!strcmp(msg, "fetch first")) {
670 status = REF_STATUS_REJECT_FETCH_FIRST;
671 free(msg);
672 msg = NULL;
673 }
674 else if (!strcmp(msg, "needs force")) {
675 status = REF_STATUS_REJECT_NEEDS_FORCE;
676 free(msg);
677 msg = NULL;
678 }
d2e73c6f
SR
679 }
680
681 if (*ref)
682 *ref = find_ref_by_name(*ref, refname);
683 if (!*ref)
684 *ref = find_ref_by_name(remote_refs, refname);
685 if (!*ref) {
686 warning("helper reported unexpected status of %s", refname);
687 return;
688 }
689
690 if ((*ref)->status != REF_STATUS_NONE) {
691 /*
692 * Earlier, the ref was marked not to be pushed, so ignore the ref
693 * status reported by the remote helper if the latter is 'no match'.
694 */
695 if (status == REF_STATUS_NONE)
696 return;
697 }
698
699 (*ref)->status = status;
700 (*ref)->remote_status = msg;
701}
702
703static void push_update_refs_status(struct helper_data *data,
704 struct ref *remote_refs)
705{
706 struct strbuf buf = STRBUF_INIT;
707 struct ref *ref = remote_refs;
708 for (;;) {
709 recvline(data, &buf);
710 if (!buf.len)
711 break;
712
713 push_update_ref_status(&buf, &ref, remote_refs);
714 }
715 strbuf_release(&buf);
716}
717
73b49a75 718static int push_refs_with_push(struct transport *transport,
ae4efe19
SP
719 struct ref *remote_refs, int flags)
720{
721 int force_all = flags & TRANSPORT_PUSH_FORCE;
722 int mirror = flags & TRANSPORT_PUSH_MIRROR;
723 struct helper_data *data = transport->data;
724 struct strbuf buf = STRBUF_INIT;
ae4efe19
SP
725 struct ref *ref;
726
c0aa335c 727 get_helper(transport);
ae4efe19
SP
728 if (!data->push)
729 return 1;
730
731 for (ref = remote_refs; ref; ref = ref->next) {
20e8b465 732 if (!ref->peer_ref && !mirror)
ae4efe19
SP
733 continue;
734
20e8b465
TRC
735 /* Check for statuses set by set_ref_status_for_push() */
736 switch (ref->status) {
737 case REF_STATUS_REJECT_NONFASTFORWARD:
dbfeddb1 738 case REF_STATUS_REJECT_ALREADY_EXISTS:
20e8b465 739 case REF_STATUS_UPTODATE:
ae4efe19 740 continue;
20e8b465
TRC
741 default:
742 ; /* do nothing */
ae4efe19
SP
743 }
744
745 if (force_all)
746 ref->force = 1;
747
748 strbuf_addstr(&buf, "push ");
749 if (!ref->deletion) {
750 if (ref->force)
751 strbuf_addch(&buf, '+');
752 if (ref->peer_ref)
753 strbuf_addstr(&buf, ref->peer_ref->name);
754 else
755 strbuf_addstr(&buf, sha1_to_hex(ref->new_sha1));
756 }
757 strbuf_addch(&buf, ':');
758 strbuf_addstr(&buf, ref->name);
759 strbuf_addch(&buf, '\n');
760 }
d8f67d20
CB
761 if (buf.len == 0)
762 return 0;
ae4efe19 763
ae4efe19
SP
764 standard_options(transport);
765
766 if (flags & TRANSPORT_PUSH_DRY_RUN) {
767 if (set_helper_option(transport, "dry-run", "true") != 0)
768 die("helper %s does not support dry-run", data->name);
769 }
770
771 strbuf_addch(&buf, '\n');
bf3c523c 772 sendline(data, &buf);
ae4efe19 773 strbuf_release(&buf);
d2e73c6f
SR
774
775 push_update_refs_status(data, remote_refs);
ae4efe19
SP
776 return 0;
777}
778
73b49a75
SR
779static int push_refs_with_export(struct transport *transport,
780 struct ref *remote_refs, int flags)
781{
782 struct ref *ref;
783 struct child_process *helper, exporter;
784 struct helper_data *data = transport->data;
183113a5 785 struct string_list revlist_args = STRING_LIST_INIT_NODUP;
73b49a75
SR
786 struct strbuf buf = STRBUF_INIT;
787
788 helper = get_helper(transport);
789
790 write_constant(helper->in, "export\n");
791
73b49a75
SR
792 strbuf_reset(&buf);
793
794 for (ref = remote_refs; ref; ref = ref->next) {
795 char *private;
796 unsigned char sha1[20];
797
798 if (!data->refspecs)
799 continue;
800 private = apply_refspecs(data->refspecs, data->refspec_nr, ref->name);
801 if (private && !get_sha1(private, sha1)) {
802 strbuf_addf(&buf, "^%s", private);
1d2f80fa 803 string_list_append(&revlist_args, strbuf_detach(&buf, NULL));
5034fdea 804 hashcpy(ref->old_sha1, sha1);
73b49a75 805 }
2faa1527 806 free(private);
73b49a75 807
105fe3e4
SR
808 if (ref->deletion) {
809 die("remote-helpers do not support ref deletion");
810 }
811
3ea7d094
JK
812 if (ref->peer_ref)
813 string_list_append(&revlist_args, ref->peer_ref->name);
73b49a75
SR
814
815 }
816
a515ebe9 817 if (get_exporter(transport, &exporter, &revlist_args))
73b49a75
SR
818 die("Couldn't run fast-export");
819
cc567322
SR
820 if (finish_command(&exporter))
821 die("Error while running fast-export");
6c8151a3 822 push_update_refs_status(data, remote_refs);
73b49a75
SR
823 return 0;
824}
825
826static int push_refs(struct transport *transport,
827 struct ref *remote_refs, int flags)
828{
829 struct helper_data *data = transport->data;
830
831 if (process_connect(transport, 1)) {
832 do_take_over(transport);
833 return transport->push_refs(transport, remote_refs, flags);
834 }
835
836 if (!remote_refs) {
837 fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
838 "Perhaps you should specify a branch such as 'master'.\n");
839 return 0;
840 }
841
842 if (data->push)
843 return push_refs_with_push(transport, remote_refs, flags);
844
845 if (data->export)
846 return push_refs_with_export(transport, remote_refs, flags);
847
848 return -1;
849}
850
851
f8ec9167
DB
852static int has_attribute(const char *attrs, const char *attr) {
853 int len;
854 if (!attrs)
855 return 0;
856
857 len = strlen(attr);
858 for (;;) {
859 const char *space = strchrnul(attrs, ' ');
860 if (len == space - attrs && !strncmp(attrs, attr, len))
861 return 1;
862 if (!*space)
863 return 0;
864 attrs = space + 1;
865 }
866}
867
6eb996b5
DB
868static struct ref *get_refs_list(struct transport *transport, int for_push)
869{
292ce46b 870 struct helper_data *data = transport->data;
6eb996b5
DB
871 struct child_process *helper;
872 struct ref *ret = NULL;
873 struct ref **tail = &ret;
874 struct ref *posn;
875 struct strbuf buf = STRBUF_INIT;
6eb996b5
DB
876
877 helper = get_helper(transport);
2d14d65c 878
fa8c097c
IL
879 if (process_connect(transport, for_push)) {
880 do_take_over(transport);
881 return transport->get_refs_list(transport, for_push);
882 }
883
ae4efe19
SP
884 if (data->push && for_push)
885 write_str_in_full(helper->in, "list for-push\n");
886 else
887 write_str_in_full(helper->in, "list\n");
6eb996b5 888
6eb996b5
DB
889 while (1) {
890 char *eov, *eon;
bf3c523c 891 recvline(data, &buf);
6eb996b5
DB
892
893 if (!*buf.buf)
894 break;
895
896 eov = strchr(buf.buf, ' ');
897 if (!eov)
898 die("Malformed response in ref list: %s", buf.buf);
899 eon = strchr(eov + 1, ' ');
900 *eov = '\0';
901 if (eon)
902 *eon = '\0';
903 *tail = alloc_ref(eov + 1);
904 if (buf.buf[0] == '@')
905 (*tail)->symref = xstrdup(buf.buf + 1);
906 else if (buf.buf[0] != '?')
907 get_sha1_hex(buf.buf, (*tail)->old_sha1);
f8ec9167
DB
908 if (eon) {
909 if (has_attribute(eon + 1, "unchanged")) {
910 (*tail)->status |= REF_STATUS_UPTODATE;
911 read_ref((*tail)->name, (*tail)->old_sha1);
912 }
913 }
6eb996b5
DB
914 tail = &((*tail)->next);
915 }
bf3c523c
IL
916 if (debug)
917 fprintf(stderr, "Debug: Read ref listing.\n");
6eb996b5
DB
918 strbuf_release(&buf);
919
920 for (posn = ret; posn; posn = posn->next)
921 resolve_remote_symref(posn, ret);
922
923 return ret;
924}
925
c9e388bb 926int transport_helper_init(struct transport *transport, const char *name)
6eb996b5
DB
927{
928 struct helper_data *data = xcalloc(sizeof(*data), 1);
c9e388bb 929 data->name = name;
6eb996b5 930
bf3c523c
IL
931 if (getenv("GIT_TRANSPORT_HELPER_DEBUG"))
932 debug = 1;
933
6eb996b5 934 transport->data = data;
ef08ef9e 935 transport->set_option = set_helper_option;
6eb996b5
DB
936 transport->get_refs_list = get_refs_list;
937 transport->fetch = fetch;
ae4efe19 938 transport->push_refs = push_refs;
f2a37151 939 transport->disconnect = release_helper;
b236752a 940 transport->connect = connect_helper;
61b075bd 941 transport->smart_options = &(data->transport_options);
6eb996b5
DB
942 return 0;
943}
419f37db
IL
944
945/*
946 * Linux pipes can buffer 65536 bytes at once (and most platforms can
947 * buffer less), so attempt reads and writes with up to that size.
948 */
949#define BUFFERSIZE 65536
950/* This should be enough to hold debugging message. */
951#define PBUFFERSIZE 8192
952
953/* Print bidirectional transfer loop debug message. */
954static void transfer_debug(const char *fmt, ...)
955{
956 va_list args;
957 char msgbuf[PBUFFERSIZE];
958 static int debug_enabled = -1;
959
960 if (debug_enabled < 0)
961 debug_enabled = getenv("GIT_TRANSLOOP_DEBUG") ? 1 : 0;
962 if (!debug_enabled)
963 return;
964
965 va_start(args, fmt);
966 vsnprintf(msgbuf, PBUFFERSIZE, fmt, args);
967 va_end(args);
968 fprintf(stderr, "Transfer loop debugging: %s\n", msgbuf);
969}
970
971/* Stream state: More data may be coming in this direction. */
972#define SSTATE_TRANSFERING 0
973/*
974 * Stream state: No more data coming in this direction, flushing rest of
975 * data.
976 */
977#define SSTATE_FLUSHING 1
978/* Stream state: Transfer in this direction finished. */
979#define SSTATE_FINISHED 2
980
981#define STATE_NEEDS_READING(state) ((state) <= SSTATE_TRANSFERING)
982#define STATE_NEEDS_WRITING(state) ((state) <= SSTATE_FLUSHING)
983#define STATE_NEEDS_CLOSING(state) ((state) == SSTATE_FLUSHING)
984
985/* Unidirectional transfer. */
986struct unidirectional_transfer {
987 /* Source */
988 int src;
989 /* Destination */
990 int dest;
991 /* Is source socket? */
992 int src_is_sock;
993 /* Is destination socket? */
994 int dest_is_sock;
995 /* Transfer state (TRANSFERING/FLUSHING/FINISHED) */
996 int state;
997 /* Buffer. */
998 char buf[BUFFERSIZE];
999 /* Buffer used. */
1000 size_t bufuse;
1001 /* Name of source. */
1002 const char *src_name;
1003 /* Name of destination. */
1004 const char *dest_name;
1005};
1006
1007/* Closes the target (for writing) if transfer has finished. */
1008static void udt_close_if_finished(struct unidirectional_transfer *t)
1009{
1010 if (STATE_NEEDS_CLOSING(t->state) && !t->bufuse) {
1011 t->state = SSTATE_FINISHED;
1012 if (t->dest_is_sock)
1013 shutdown(t->dest, SHUT_WR);
1014 else
1015 close(t->dest);
1016 transfer_debug("Closed %s.", t->dest_name);
1017 }
1018}
1019
1020/*
1021 * Tries to read read data from source into buffer. If buffer is full,
1022 * no data is read. Returns 0 on success, -1 on error.
1023 */
1024static int udt_do_read(struct unidirectional_transfer *t)
1025{
1026 ssize_t bytes;
1027
1028 if (t->bufuse == BUFFERSIZE)
1029 return 0; /* No space for more. */
1030
1031 transfer_debug("%s is readable", t->src_name);
1032 bytes = read(t->src, t->buf + t->bufuse, BUFFERSIZE - t->bufuse);
1033 if (bytes < 0 && errno != EWOULDBLOCK && errno != EAGAIN &&
1034 errno != EINTR) {
1035 error("read(%s) failed: %s", t->src_name, strerror(errno));
1036 return -1;
1037 } else if (bytes == 0) {
1038 transfer_debug("%s EOF (with %i bytes in buffer)",
1039 t->src_name, t->bufuse);
1040 t->state = SSTATE_FLUSHING;
1041 } else if (bytes > 0) {
1042 t->bufuse += bytes;
1043 transfer_debug("Read %i bytes from %s (buffer now at %i)",
1044 (int)bytes, t->src_name, (int)t->bufuse);
1045 }
1046 return 0;
1047}
1048
1049/* Tries to write data from buffer into destination. If buffer is empty,
1050 * no data is written. Returns 0 on success, -1 on error.
1051 */
1052static int udt_do_write(struct unidirectional_transfer *t)
1053{
803dbdb9 1054 ssize_t bytes;
419f37db
IL
1055
1056 if (t->bufuse == 0)
1057 return 0; /* Nothing to write. */
1058
1059 transfer_debug("%s is writable", t->dest_name);
1060 bytes = write(t->dest, t->buf, t->bufuse);
1061 if (bytes < 0 && errno != EWOULDBLOCK && errno != EAGAIN &&
1062 errno != EINTR) {
1063 error("write(%s) failed: %s", t->dest_name, strerror(errno));
1064 return -1;
1065 } else if (bytes > 0) {
1066 t->bufuse -= bytes;
1067 if (t->bufuse)
1068 memmove(t->buf, t->buf + bytes, t->bufuse);
1069 transfer_debug("Wrote %i bytes to %s (buffer now at %i)",
1070 (int)bytes, t->dest_name, (int)t->bufuse);
1071 }
1072 return 0;
1073}
1074
1075
1076/* State of bidirectional transfer loop. */
1077struct bidirectional_transfer_state {
1078 /* Direction from program to git. */
1079 struct unidirectional_transfer ptg;
1080 /* Direction from git to program. */
1081 struct unidirectional_transfer gtp;
1082};
1083
1084static void *udt_copy_task_routine(void *udt)
1085{
1086 struct unidirectional_transfer *t = (struct unidirectional_transfer *)udt;
1087 while (t->state != SSTATE_FINISHED) {
1088 if (STATE_NEEDS_READING(t->state))
1089 if (udt_do_read(t))
1090 return NULL;
1091 if (STATE_NEEDS_WRITING(t->state))
1092 if (udt_do_write(t))
1093 return NULL;
1094 if (STATE_NEEDS_CLOSING(t->state))
1095 udt_close_if_finished(t);
1096 }
1097 return udt; /* Just some non-NULL value. */
1098}
1099
1100#ifndef NO_PTHREADS
1101
1102/*
1103 * Join thread, with apporiate errors on failure. Name is name for the
1104 * thread (for error messages). Returns 0 on success, 1 on failure.
1105 */
1106static int tloop_join(pthread_t thread, const char *name)
1107{
1108 int err;
1109 void *tret;
1110 err = pthread_join(thread, &tret);
1111 if (!tret) {
1112 error("%s thread failed", name);
1113 return 1;
1114 }
1115 if (err) {
1116 error("%s thread failed to join: %s", name, strerror(err));
1117 return 1;
1118 }
1119 return 0;
1120}
1121
1122/*
1123 * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1124 * -1 on failure.
1125 */
1126static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1127{
1128 pthread_t gtp_thread;
1129 pthread_t ptg_thread;
1130 int err;
1131 int ret = 0;
1132 err = pthread_create(&gtp_thread, NULL, udt_copy_task_routine,
1133 &s->gtp);
1134 if (err)
1135 die("Can't start thread for copying data: %s", strerror(err));
1136 err = pthread_create(&ptg_thread, NULL, udt_copy_task_routine,
1137 &s->ptg);
1138 if (err)
1139 die("Can't start thread for copying data: %s", strerror(err));
1140
1141 ret |= tloop_join(gtp_thread, "Git to program copy");
1142 ret |= tloop_join(ptg_thread, "Program to git copy");
1143 return ret;
1144}
1145#else
1146
1147/* Close the source and target (for writing) for transfer. */
1148static void udt_kill_transfer(struct unidirectional_transfer *t)
1149{
1150 t->state = SSTATE_FINISHED;
1151 /*
1152 * Socket read end left open isn't a disaster if nobody
1153 * attempts to read from it (mingw compat headers do not
1154 * have SHUT_RD)...
1155 *
1156 * We can't fully close the socket since otherwise gtp
1157 * task would first close the socket it sends data to
1158 * while closing the ptg file descriptors.
1159 */
1160 if (!t->src_is_sock)
1161 close(t->src);
1162 if (t->dest_is_sock)
1163 shutdown(t->dest, SHUT_WR);
1164 else
1165 close(t->dest);
1166}
1167
1168/*
1169 * Join process, with apporiate errors on failure. Name is name for the
1170 * process (for error messages). Returns 0 on success, 1 on failure.
1171 */
1172static int tloop_join(pid_t pid, const char *name)
1173{
1174 int tret;
1175 if (waitpid(pid, &tret, 0) < 0) {
1176 error("%s process failed to wait: %s", name, strerror(errno));
1177 return 1;
1178 }
1179 if (!WIFEXITED(tret) || WEXITSTATUS(tret)) {
1180 error("%s process failed", name);
1181 return 1;
1182 }
1183 return 0;
1184}
1185
1186/*
1187 * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1188 * -1 on failure.
1189 */
1190static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1191{
1192 pid_t pid1, pid2;
1193 int ret = 0;
1194
1195 /* Fork thread #1: git to program. */
1196 pid1 = fork();
1197 if (pid1 < 0)
1198 die_errno("Can't start thread for copying data");
1199 else if (pid1 == 0) {
1200 udt_kill_transfer(&s->ptg);
1201 exit(udt_copy_task_routine(&s->gtp) ? 0 : 1);
1202 }
1203
1204 /* Fork thread #2: program to git. */
1205 pid2 = fork();
1206 if (pid2 < 0)
1207 die_errno("Can't start thread for copying data");
1208 else if (pid2 == 0) {
1209 udt_kill_transfer(&s->gtp);
1210 exit(udt_copy_task_routine(&s->ptg) ? 0 : 1);
1211 }
1212
1213 /*
1214 * Close both streams in parent as to not interfere with
1215 * end of file detection and wait for both tasks to finish.
1216 */
1217 udt_kill_transfer(&s->gtp);
1218 udt_kill_transfer(&s->ptg);
1219 ret |= tloop_join(pid1, "Git to program copy");
1220 ret |= tloop_join(pid2, "Program to git copy");
1221 return ret;
1222}
1223#endif
1224
1225/*
1226 * Copies data from stdin to output and from input to stdout simultaneously.
1227 * Additionally filtering through given filter. If filter is NULL, uses
1228 * identity filter.
1229 */
1230int bidirectional_transfer_loop(int input, int output)
1231{
1232 struct bidirectional_transfer_state state;
1233
1234 /* Fill the state fields. */
1235 state.ptg.src = input;
1236 state.ptg.dest = 1;
1237 state.ptg.src_is_sock = (input == output);
1238 state.ptg.dest_is_sock = 0;
1239 state.ptg.state = SSTATE_TRANSFERING;
1240 state.ptg.bufuse = 0;
1241 state.ptg.src_name = "remote input";
1242 state.ptg.dest_name = "stdout";
1243
1244 state.gtp.src = 0;
1245 state.gtp.dest = output;
1246 state.gtp.src_is_sock = 0;
1247 state.gtp.dest_is_sock = (input == output);
1248 state.gtp.state = SSTATE_TRANSFERING;
1249 state.gtp.bufuse = 0;
1250 state.gtp.src_name = "stdin";
1251 state.gtp.dest_name = "remote output";
1252
1253 return tloop_spawnwait_tasks(&state);
1254}