Merge branch 'rs/nth-switch-code-simplification'
[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"
72ff8943 8#include "remote.h"
73b49a75 9#include "string-list.h"
7851b1e6 10#include "thread-utils.h"
c34fe630 11#include "sigchain.h"
bfc366d9 12#include "argv-array.h"
664059fb 13#include "refs.h"
ec0cb496 14#include "refspec.h"
e967ca38 15#include "transport-internal.h"
edc9caf7 16#include "protocol.h"
7851b1e6 17
bf3c523c
IL
18static int debug;
19
9cba13ca 20struct helper_data {
6eb996b5
DB
21 const char *name;
22 struct child_process *helper;
292ce46b 23 FILE *out;
ef08ef9e 24 unsigned fetch : 1,
a24a32dd 25 import : 1,
bfc366d9 26 bidi_import : 1,
73b49a75 27 export : 1,
ae4efe19 28 option : 1,
fa8c097c
IL
29 push : 1,
30 connect : 1,
edc9caf7 31 stateless_connect : 1,
0d957a4d 32 signed_tags : 1,
9ba38048 33 check_connectivity : 1,
597b831a
MM
34 no_disconnect_req : 1,
35 no_private_update : 1;
ac3fda82
JT
36
37 /*
38 * As an optimization, the transport code may invoke fetch before
39 * get_refs_list. If this happens, and if the transport helper doesn't
40 * support connect or stateless_connect, we need to invoke
41 * get_refs_list ourselves if we haven't already done so. Keep track of
42 * whether we have invoked get_refs_list.
43 */
44 unsigned get_refs_list_called : 1;
45
a515ebe9
SR
46 char *export_marks;
47 char *import_marks;
72ff8943 48 /* These go from remote name (as in "list") to private name */
57f32ac2 49 struct refspec rs;
61b075bd
IL
50 /* Transport options for fetch-pack/send-pack (should one of
51 * those be invoked).
52 */
53 struct git_transport_options transport_options;
6eb996b5
DB
54};
55
bf3c523c
IL
56static void sendline(struct helper_data *helper, struct strbuf *buffer)
57{
58 if (debug)
59 fprintf(stderr, "Debug: Remote helper: -> %s", buffer->buf);
06f46f23 60 if (write_in_full(helper->helper->in, buffer->buf, buffer->len) < 0)
6b5b309f 61 die_errno(_("full write to remote helper failed"));
bf3c523c
IL
62}
63
b1c2edfc 64static int recvline_fh(FILE *helper, struct strbuf *buffer)
bf3c523c
IL
65{
66 strbuf_reset(buffer);
67 if (debug)
68 fprintf(stderr, "Debug: Remote helper: Waiting...\n");
692dfdfa 69 if (strbuf_getline(buffer, helper) == EOF) {
bf3c523c
IL
70 if (debug)
71 fprintf(stderr, "Debug: Remote helper quit.\n");
5931b33e 72 return 1;
bf3c523c
IL
73 }
74
75 if (debug)
76 fprintf(stderr, "Debug: Remote helper: <- %s\n", buffer->buf);
77 return 0;
78}
79
fa8c097c
IL
80static int recvline(struct helper_data *helper, struct strbuf *buffer)
81{
b1c2edfc 82 return recvline_fh(helper->out, buffer);
fa8c097c
IL
83}
84
bf3c523c
IL
85static void write_constant(int fd, const char *str)
86{
87 if (debug)
88 fprintf(stderr, "Debug: Remote helper: -> %s", str);
06f46f23 89 if (write_in_full(fd, str, strlen(str)) < 0)
6b5b309f 90 die_errno(_("full write to remote helper failed"));
bf3c523c
IL
91}
92
c2e86add 93static const char *remove_ext_force(const char *url)
25d5cc48
IL
94{
95 if (url) {
96 const char *colon = strchr(url, ':');
97 if (colon && colon[1] == ':')
98 return colon + 2;
99 }
100 return url;
101}
102
fa8c097c
IL
103static void do_take_over(struct transport *transport)
104{
105 struct helper_data *data;
106 data = (struct helper_data *)transport->data;
107 transport_take_over(transport, data->helper);
108 fclose(data->out);
109 free(data);
110}
111
2879bc3b
MH
112static void standard_options(struct transport *t);
113
6eb996b5
DB
114static struct child_process *get_helper(struct transport *transport)
115{
116 struct helper_data *data = transport->data;
117 struct strbuf buf = STRBUF_INIT;
118 struct child_process *helper;
61b075bd 119 int duped;
6b02de3b 120 int code;
6eb996b5
DB
121
122 if (data->helper)
123 return data->helper;
124
483bbd4e
RS
125 helper = xmalloc(sizeof(*helper));
126 child_process_init(helper);
6eb996b5
DB
127 helper->in = -1;
128 helper->out = -1;
129 helper->err = 0;
e0ab2ac6
JK
130 argv_array_pushf(&helper->args, "git-remote-%s", data->name);
131 argv_array_push(&helper->args, transport->remote->name);
132 argv_array_push(&helper->args, remove_ext_force(transport->url));
6b02de3b
IL
133 helper->git_cmd = 0;
134 helper->silent_exec_failure = 1;
e1735872 135
4b0c3c77
JN
136 if (have_git_dir())
137 argv_array_pushf(&helper->env_array, "%s=%s",
138 GIT_DIR_ENVIRONMENT, get_git_dir());
e1735872 139
abd81a3d
JH
140 helper->trace2_child_class = helper->args.argv[0]; /* "remote-<name>" */
141
6b02de3b
IL
142 code = start_command(helper);
143 if (code < 0 && errno == ENOENT)
6b5b309f 144 die(_("unable to find remote helper for '%s'"), data->name);
6b02de3b
IL
145 else if (code != 0)
146 exit(code);
147
6eb996b5 148 data->helper = helper;
fa8c097c 149 data->no_disconnect_req = 0;
57f32ac2 150 refspec_init(&data->rs, REFSPEC_FETCH);
6eb996b5 151
61b075bd 152 /*
1a0c8dfd
JH
153 * Open the output as FILE* so strbuf_getline_*() family of
154 * functions can be used.
61b075bd
IL
155 * Do this with duped fd because fclose() will close the fd,
156 * and stuff like taking over will require the fd to remain.
61b075bd
IL
157 */
158 duped = dup(helper->out);
159 if (duped < 0)
6b5b309f 160 die_errno(_("can't dup helper output fd"));
61b075bd
IL
161 data->out = xfdopen(duped, "r");
162
bf3c523c 163 write_constant(helper->in, "capabilities\n");
2d14d65c 164
6eb996b5 165 while (1) {
21a2d4ad 166 const char *capname, *arg;
28ed5b35 167 int mandatory = 0;
5931b33e
FC
168 if (recvline(data, &buf))
169 exit(128);
6eb996b5
DB
170
171 if (!*buf.buf)
172 break;
28ed5b35
IL
173
174 if (*buf.buf == '*') {
175 capname = buf.buf + 1;
176 mandatory = 1;
177 } else
178 capname = buf.buf;
179
bf3c523c 180 if (debug)
28ed5b35
IL
181 fprintf(stderr, "Debug: Got cap %s\n", capname);
182 if (!strcmp(capname, "fetch"))
6eb996b5 183 data->fetch = 1;
28ed5b35 184 else if (!strcmp(capname, "option"))
ef08ef9e 185 data->option = 1;
28ed5b35 186 else if (!strcmp(capname, "push"))
ae4efe19 187 data->push = 1;
28ed5b35 188 else if (!strcmp(capname, "import"))
e65e91ed 189 data->import = 1;
bfc366d9
FA
190 else if (!strcmp(capname, "bidi-import"))
191 data->bidi_import = 1;
73b49a75
SR
192 else if (!strcmp(capname, "export"))
193 data->export = 1;
9ba38048
NTND
194 else if (!strcmp(capname, "check-connectivity"))
195 data->check_connectivity = 1;
57f32ac2
BW
196 else if (skip_prefix(capname, "refspec ", &arg)) {
197 refspec_append(&data->rs, arg);
fa8c097c
IL
198 } else if (!strcmp(capname, "connect")) {
199 data->connect = 1;
edc9caf7
BW
200 } else if (!strcmp(capname, "stateless-connect")) {
201 data->stateless_connect = 1;
0d957a4d
JK
202 } else if (!strcmp(capname, "signed-tags")) {
203 data->signed_tags = 1;
21a2d4ad
JK
204 } else if (skip_prefix(capname, "export-marks ", &arg)) {
205 data->export_marks = xstrdup(arg);
206 } else if (skip_prefix(capname, "import-marks ", &arg)) {
207 data->import_marks = xstrdup(arg);
59556548 208 } else if (starts_with(capname, "no-private-update")) {
597b831a 209 data->no_private_update = 1;
28ed5b35 210 } else if (mandatory) {
6b5b309f
NTND
211 die(_("unknown mandatory capability %s; this remote "
212 "helper probably needs newer version of Git"),
28ed5b35 213 capname);
72ff8943
DB
214 }
215 }
57f32ac2 216 if (!data->rs.nr && (data->import || data->bidi_import || data->export)) {
6b5b309f 217 warning(_("this remote helper should implement refspec capability"));
6eb996b5 218 }
b962dbdc 219 strbuf_release(&buf);
bf3c523c
IL
220 if (debug)
221 fprintf(stderr, "Debug: Capabilities complete.\n");
2879bc3b 222 standard_options(transport);
6eb996b5
DB
223 return data->helper;
224}
225
226static int disconnect_helper(struct transport *transport)
227{
228 struct helper_data *data = transport->data;
cc567322 229 int res = 0;
bf3c523c 230
6eb996b5 231 if (data->helper) {
bf3c523c
IL
232 if (debug)
233 fprintf(stderr, "Debug: Disconnecting.\n");
fa8c097c 234 if (!data->no_disconnect_req) {
c34fe630
JK
235 /*
236 * Ignore write errors; there's nothing we can do,
237 * since we're about to close the pipe anyway. And the
238 * most likely error is EPIPE due to the helper dying
239 * to report an error itself.
240 */
241 sigchain_push(SIGPIPE, SIG_IGN);
242 xwrite(data->helper->in, "\n", 1);
243 sigchain_pop(SIGPIPE);
fa8c097c 244 }
6eb996b5 245 close(data->helper->in);
61b075bd 246 close(data->helper->out);
292ce46b 247 fclose(data->out);
cc567322 248 res = finish_command(data->helper);
6a83d902 249 FREE_AND_NULL(data->helper);
6eb996b5 250 }
cc567322 251 return res;
6eb996b5
DB
252}
253
ef08ef9e
SP
254static const char *unsupported_options[] = {
255 TRANS_OPT_UPLOADPACK,
256 TRANS_OPT_RECEIVEPACK,
257 TRANS_OPT_THIN,
258 TRANS_OPT_KEEP
259 };
23cd01ec 260
ef08ef9e
SP
261static const char *boolean_options[] = {
262 TRANS_OPT_THIN,
263 TRANS_OPT_KEEP,
0ea47f9d 264 TRANS_OPT_FOLLOWTAGS,
cccf74e2 265 TRANS_OPT_DEEPEN_RELATIVE
ef08ef9e
SP
266 };
267
9318c5dd
NTND
268static int strbuf_set_helper_option(struct helper_data *data,
269 struct strbuf *buf)
270{
271 int ret;
272
273 sendline(data, buf);
274 if (recvline(data, buf))
275 exit(128);
276
277 if (!strcmp(buf->buf, "ok"))
278 ret = 0;
279 else if (starts_with(buf->buf, "error"))
280 ret = -1;
281 else if (!strcmp(buf->buf, "unsupported"))
282 ret = 1;
283 else {
6b5b309f 284 warning(_("%s unexpectedly said: '%s'"), data->name, buf->buf);
9318c5dd
NTND
285 ret = 1;
286 }
287 return ret;
288}
289
a45a2600
NTND
290static int string_list_set_helper_option(struct helper_data *data,
291 const char *name,
292 struct string_list *list)
293{
294 struct strbuf buf = STRBUF_INIT;
295 int i, ret = 0;
296
297 for (i = 0; i < list->nr; i++) {
298 strbuf_addf(&buf, "option %s ", name);
299 quote_c_style(list->items[i].string, &buf, NULL, 0);
300 strbuf_addch(&buf, '\n');
301
302 if ((ret = strbuf_set_helper_option(data, &buf)))
303 break;
304 strbuf_reset(&buf);
305 }
306 strbuf_release(&buf);
307 return ret;
308}
309
ef08ef9e
SP
310static int set_helper_option(struct transport *transport,
311 const char *name, const char *value)
312{
313 struct helper_data *data = transport->data;
ef08ef9e
SP
314 struct strbuf buf = STRBUF_INIT;
315 int i, ret, is_bool = 0;
316
bf3c523c
IL
317 get_helper(transport);
318
ef08ef9e
SP
319 if (!data->option)
320 return 1;
321
a45a2600
NTND
322 if (!strcmp(name, "deepen-not"))
323 return string_list_set_helper_option(data, name,
324 (struct string_list *)value);
325
ef08ef9e
SP
326 for (i = 0; i < ARRAY_SIZE(unsupported_options); i++) {
327 if (!strcmp(name, unsupported_options[i]))
328 return 1;
329 }
330
331 for (i = 0; i < ARRAY_SIZE(boolean_options); i++) {
332 if (!strcmp(name, boolean_options[i])) {
333 is_bool = 1;
334 break;
335 }
336 }
337
338 strbuf_addf(&buf, "option %s ", name);
339 if (is_bool)
340 strbuf_addstr(&buf, value ? "true" : "false");
341 else
342 quote_c_style(value, &buf, NULL, 0);
343 strbuf_addch(&buf, '\n');
344
9318c5dd 345 ret = strbuf_set_helper_option(data, &buf);
ef08ef9e
SP
346 strbuf_release(&buf);
347 return ret;
348}
349
350static void standard_options(struct transport *t)
351{
352 char buf[16];
ef08ef9e 353 int v = t->verbose;
ef08ef9e 354
d01b3c02 355 set_helper_option(t, "progress", t->progress ? "true" : "false");
ef08ef9e 356
8c5acfb9 357 xsnprintf(buf, sizeof(buf), "%d", v + 1);
ef08ef9e 358 set_helper_option(t, "verbosity", buf);
c915f11e
EW
359
360 switch (t->family) {
361 case TRANSPORT_FAMILY_ALL:
362 /*
363 * this is already the default,
364 * do not break old remote helpers by setting "all" here
365 */
366 break;
367 case TRANSPORT_FAMILY_IPV4:
368 set_helper_option(t, "family", "ipv4");
369 break;
370 case TRANSPORT_FAMILY_IPV6:
371 set_helper_option(t, "family", "ipv6");
372 break;
373 }
ef08ef9e
SP
374}
375
f2a37151
DB
376static int release_helper(struct transport *transport)
377{
cc567322 378 int res = 0;
72ff8943 379 struct helper_data *data = transport->data;
57f32ac2 380 refspec_clear(&data->rs);
cc567322 381 res = disconnect_helper(transport);
f2a37151 382 free(transport->data);
cc567322 383 return res;
f2a37151
DB
384}
385
6eb996b5 386static int fetch_with_fetch(struct transport *transport,
37148311 387 int nr_heads, struct ref **to_fetch)
6eb996b5 388{
292ce46b 389 struct helper_data *data = transport->data;
6eb996b5
DB
390 int i;
391 struct strbuf buf = STRBUF_INIT;
392
393 for (i = 0; i < nr_heads; i++) {
1088261f 394 const struct ref *posn = to_fetch[i];
6eb996b5
DB
395 if (posn->status & REF_STATUS_UPTODATE)
396 continue;
2d14d65c
DB
397
398 strbuf_addf(&buf, "fetch %s %s\n",
f4e54d02 399 oid_to_hex(&posn->old_oid),
33cae542 400 posn->symref ? posn->symref : posn->name);
292ce46b 401 }
2d14d65c 402
292ce46b 403 strbuf_addch(&buf, '\n');
bf3c523c 404 sendline(data, &buf);
292ce46b
SP
405
406 while (1) {
5931b33e
FC
407 if (recvline(data, &buf))
408 exit(128);
292ce46b 409
59556548 410 if (starts_with(buf.buf, "lock ")) {
292ce46b
SP
411 const char *name = buf.buf + 5;
412 if (transport->pack_lockfile)
6b5b309f 413 warning(_("%s also locked %s"), data->name, name);
292ce46b
SP
414 else
415 transport->pack_lockfile = xstrdup(name);
416 }
9ba38048
NTND
417 else if (data->check_connectivity &&
418 data->transport_options.check_self_contained_and_connected &&
419 !strcmp(buf.buf, "connectivity-ok"))
420 data->transport_options.self_contained_and_connected = 1;
292ce46b
SP
421 else if (!buf.len)
422 break;
423 else
6b5b309f 424 warning(_("%s unexpectedly said: '%s'"), data->name, buf.buf);
6eb996b5 425 }
292ce46b 426 strbuf_release(&buf);
6eb996b5
DB
427 return 0;
428}
429
e65e91ed
DB
430static int get_importer(struct transport *transport, struct child_process *fastimport)
431{
432 struct child_process *helper = get_helper(transport);
bfc366d9 433 struct helper_data *data = transport->data;
bfc366d9 434 int cat_blob_fd, code;
483bbd4e 435 child_process_init(fastimport);
8b355427 436 fastimport->in = xdup(helper->out);
173fd1a1
JK
437 argv_array_push(&fastimport->args, "fast-import");
438 argv_array_push(&fastimport->args, debug ? "--stats" : "--quiet");
e65e91ed 439
bfc366d9
FA
440 if (data->bidi_import) {
441 cat_blob_fd = xdup(helper->in);
173fd1a1 442 argv_array_pushf(&fastimport->args, "--cat-blob-fd=%d", cat_blob_fd);
bfc366d9 443 }
e65e91ed 444 fastimport->git_cmd = 1;
bfc366d9
FA
445
446 code = start_command(fastimport);
447 return code;
e65e91ed
DB
448}
449
73b49a75
SR
450static int get_exporter(struct transport *transport,
451 struct child_process *fastexport,
73b49a75
SR
452 struct string_list *revlist_args)
453{
a515ebe9 454 struct helper_data *data = transport->data;
73b49a75 455 struct child_process *helper = get_helper(transport);
2aeae40a 456 int i;
852e54bc 457
8828f298 458 child_process_init(fastexport);
73b49a75
SR
459
460 /* we need to duplicate helper->in because we want to use it after
461 * fastexport is done with it. */
462 fastexport->out = dup(helper->in);
2aeae40a
JK
463 argv_array_push(&fastexport->args, "fast-export");
464 argv_array_push(&fastexport->args, "--use-done-feature");
465 argv_array_push(&fastexport->args, data->signed_tags ?
466 "--signed-tags=verbatim" : "--signed-tags=warn-strip");
467 if (data->export_marks)
468 argv_array_pushf(&fastexport->args, "--export-marks=%s.tmp", data->export_marks);
469 if (data->import_marks)
470 argv_array_pushf(&fastexport->args, "--import-marks=%s", data->import_marks);
73b49a75
SR
471
472 for (i = 0; i < revlist_args->nr; i++)
2aeae40a 473 argv_array_push(&fastexport->args, revlist_args->items[i].string);
73b49a75
SR
474
475 fastexport->git_cmd = 1;
476 return start_command(fastexport);
477}
478
e65e91ed
DB
479static int fetch_with_import(struct transport *transport,
480 int nr_heads, struct ref **to_fetch)
481{
482 struct child_process fastimport;
72ff8943 483 struct helper_data *data = transport->data;
e65e91ed
DB
484 int i;
485 struct ref *posn;
486 struct strbuf buf = STRBUF_INIT;
487
bf3c523c
IL
488 get_helper(transport);
489
e65e91ed 490 if (get_importer(transport, &fastimport))
6b5b309f 491 die(_("couldn't run fast-import"));
e65e91ed
DB
492
493 for (i = 0; i < nr_heads; i++) {
494 posn = to_fetch[i];
495 if (posn->status & REF_STATUS_UPTODATE)
496 continue;
497
33cae542
MH
498 strbuf_addf(&buf, "import %s\n",
499 posn->symref ? posn->symref : posn->name);
bf3c523c 500 sendline(data, &buf);
e65e91ed
DB
501 strbuf_reset(&buf);
502 }
9504bc9d
SR
503
504 write_constant(data->helper->in, "\n");
bfc366d9
FA
505 /*
506 * remote-helpers that advertise the bidi-import capability are required to
507 * buffer the complete batch of import commands until this newline before
508 * sending data to fast-import.
509 * These helpers read back data from fast-import on their stdin, which could
510 * be mixed with import commands, otherwise.
511 */
9504bc9d 512
cc567322 513 if (finish_command(&fastimport))
6b5b309f 514 die(_("error while running fast-import"));
e65e91ed 515
dff9d65d
FA
516 /*
517 * The fast-import stream of a remote helper that advertises
518 * the "refspec" capability writes to the refs named after the
519 * right hand side of the first refspec matching each ref we
520 * were fetching.
521 *
522 * (If no "refspec" capability was specified, for historical
7a43c554 523 * reasons we default to the equivalent of *:*.)
dff9d65d
FA
524 *
525 * Store the result in to_fetch[i].old_sha1. Callers such
526 * as "git fetch" can use the value to write feedback to the
527 * terminal, populate FETCH_HEAD, and determine what new value
528 * should be written to peer_ref if the update is a
529 * fast-forward or this is a forced update.
530 */
e65e91ed 531 for (i = 0; i < nr_heads; i++) {
33cae542 532 char *private, *name;
e65e91ed
DB
533 posn = to_fetch[i];
534 if (posn->status & REF_STATUS_UPTODATE)
535 continue;
33cae542 536 name = posn->symref ? posn->symref : posn->name;
57f32ac2 537 if (data->rs.nr)
d000414e 538 private = apply_refspecs(&data->rs, name);
72ff8943 539 else
33cae542 540 private = xstrdup(name);
d51b720f 541 if (private) {
34c290a6 542 if (read_ref(private, &posn->old_oid) < 0)
6b5b309f 543 die(_("could not read ref %s"), private);
d51b720f
MH
544 free(private);
545 }
e65e91ed 546 }
b962dbdc 547 strbuf_release(&buf);
e65e91ed
DB
548 return 0;
549}
550
176e85c1 551static int run_connect(struct transport *transport, struct strbuf *cmdbuf)
fa8c097c
IL
552{
553 struct helper_data *data = transport->data;
176e85c1
BW
554 int ret = 0;
555 int duped;
fa8c097c 556 FILE *input;
176e85c1 557 struct child_process *helper;
fa8c097c
IL
558
559 helper = get_helper(transport);
560
561 /*
562 * Yes, dup the pipe another time, as we need unbuffered version
563 * of input pipe as FILE*. fclose() closes the underlying fd and
564 * stream buffering only can be changed before first I/O operation
565 * on it.
566 */
567 duped = dup(helper->out);
568 if (duped < 0)
6b5b309f 569 die_errno(_("can't dup helper output fd"));
fa8c097c
IL
570 input = xfdopen(duped, "r");
571 setvbuf(input, NULL, _IONBF, 0);
572
176e85c1
BW
573 sendline(data, cmdbuf);
574 if (recvline_fh(input, cmdbuf))
575 exit(128);
576
577 if (!strcmp(cmdbuf->buf, "")) {
578 data->no_disconnect_req = 1;
579 if (debug)
580 fprintf(stderr, "Debug: Smart transport connection "
581 "ready.\n");
582 ret = 1;
583 } else if (!strcmp(cmdbuf->buf, "fallback")) {
584 if (debug)
585 fprintf(stderr, "Debug: Falling back to dumb "
586 "transport.\n");
587 } else {
739fb716 588 die(_("unknown response to connect: %s"),
6b5b309f 589 cmdbuf->buf);
176e85c1
BW
590 }
591
592 fclose(input);
593 return ret;
594}
595
596static int process_connect_service(struct transport *transport,
597 const char *name, const char *exec)
598{
599 struct helper_data *data = transport->data;
600 struct strbuf cmdbuf = STRBUF_INIT;
601 int ret = 0;
602
fa8c097c
IL
603 /*
604 * Handle --upload-pack and friends. This is fire and forget...
605 * just warn if it fails.
606 */
607 if (strcmp(name, exec)) {
176e85c1 608 int r = set_helper_option(transport, "servpath", exec);
fa8c097c 609 if (r > 0)
6b5b309f 610 warning(_("setting remote service path not supported by protocol"));
fa8c097c 611 else if (r < 0)
6b5b309f 612 warning(_("invalid remote service path"));
fa8c097c
IL
613 }
614
176e85c1 615 if (data->connect) {
fa8c097c 616 strbuf_addf(&cmdbuf, "connect %s\n", name);
176e85c1 617 ret = run_connect(transport, &cmdbuf);
edc9caf7
BW
618 } else if (data->stateless_connect &&
619 (get_protocol_version_config() == protocol_v2) &&
620 !strcmp("git-upload-pack", name)) {
621 strbuf_addf(&cmdbuf, "stateless-connect %s\n", name);
622 ret = run_connect(transport, &cmdbuf);
623 if (ret)
624 transport->stateless_rpc = 1;
176e85c1 625 }
fa8c097c 626
4168be8e 627 strbuf_release(&cmdbuf);
fa8c097c
IL
628 return ret;
629}
630
631static int process_connect(struct transport *transport,
632 int for_push)
633{
634 struct helper_data *data = transport->data;
635 const char *name;
636 const char *exec;
637
638 name = for_push ? "git-receive-pack" : "git-upload-pack";
639 if (for_push)
640 exec = data->transport_options.receivepack;
641 else
642 exec = data->transport_options.uploadpack;
643
644 return process_connect_service(transport, name, exec);
645}
646
b236752a
IL
647static int connect_helper(struct transport *transport, const char *name,
648 const char *exec, int fd[2])
649{
650 struct helper_data *data = transport->data;
651
652 /* Get_helper so connect is inited. */
653 get_helper(transport);
654 if (!data->connect)
6b5b309f 655 die(_("operation not supported by protocol"));
b236752a
IL
656
657 if (!process_connect_service(transport, name, exec))
6b5b309f 658 die(_("can't connect to subservice %s"), name);
b236752a
IL
659
660 fd[0] = data->helper->out;
661 fd[1] = data->helper->in;
662 return 0;
663}
664
ac3fda82
JT
665static struct ref *get_refs_list_using_list(struct transport *transport,
666 int for_push);
667
6eb996b5 668static int fetch(struct transport *transport,
e2842b39 669 int nr_heads, struct ref **to_fetch)
6eb996b5
DB
670{
671 struct helper_data *data = transport->data;
672 int i, count;
673
ac3fda82
JT
674 get_helper(transport);
675
fa8c097c
IL
676 if (process_connect(transport, 0)) {
677 do_take_over(transport);
e2842b39 678 return transport->vtable->fetch(transport, nr_heads, to_fetch);
fa8c097c
IL
679 }
680
ac3fda82
JT
681 if (!data->get_refs_list_called)
682 get_refs_list_using_list(transport, 0);
683
6eb996b5
DB
684 count = 0;
685 for (i = 0; i < nr_heads; i++)
686 if (!(to_fetch[i]->status & REF_STATUS_UPTODATE))
687 count++;
688
689 if (!count)
690 return 0;
691
aab1beb0
MH
692 if (data->check_connectivity &&
693 data->transport_options.check_self_contained_and_connected)
694 set_helper_option(transport, "check-connectivity", "true");
695
696 if (transport->cloning)
697 set_helper_option(transport, "cloning", "true");
698
699 if (data->transport_options.update_shallow)
700 set_helper_option(transport, "update-shallow", "true");
701
87c2d9d3 702 if (data->transport_options.filter_options.choice) {
cf9ceb5a
MD
703 const char *spec = expand_list_objects_filter_spec(
704 &data->transport_options.filter_options);
705 set_helper_option(transport, "filter", spec);
87c2d9d3 706 }
640d8b72 707
3390e42a
JT
708 if (data->transport_options.negotiation_tips)
709 warning("Ignoring --negotiation-tip because the protocol does not support it.");
710
6eb996b5
DB
711 if (data->fetch)
712 return fetch_with_fetch(transport, nr_heads, to_fetch);
713
e65e91ed
DB
714 if (data->import)
715 return fetch_with_import(transport, nr_heads, to_fetch);
716
6eb996b5
DB
717 return -1;
718}
719
664059fb 720static int push_update_ref_status(struct strbuf *buf,
d2e73c6f
SR
721 struct ref **ref,
722 struct ref *remote_refs)
723{
724 char *refname, *msg;
f9e3c6be 725 int status, forced = 0;
d2e73c6f 726
59556548 727 if (starts_with(buf->buf, "ok ")) {
d2e73c6f
SR
728 status = REF_STATUS_OK;
729 refname = buf->buf + 3;
59556548 730 } else if (starts_with(buf->buf, "error ")) {
d2e73c6f
SR
731 status = REF_STATUS_REMOTE_REJECT;
732 refname = buf->buf + 6;
733 } else
6b5b309f 734 die(_("expected ok/error, helper said '%s'"), buf->buf);
d2e73c6f
SR
735
736 msg = strchr(refname, ' ');
737 if (msg) {
738 struct strbuf msg_buf = STRBUF_INIT;
739 const char *end;
740
741 *msg++ = '\0';
742 if (!unquote_c_style(&msg_buf, msg, &end))
743 msg = strbuf_detach(&msg_buf, NULL);
744 else
745 msg = xstrdup(msg);
746 strbuf_release(&msg_buf);
747
748 if (!strcmp(msg, "no match")) {
749 status = REF_STATUS_NONE;
6a83d902 750 FREE_AND_NULL(msg);
d2e73c6f
SR
751 }
752 else if (!strcmp(msg, "up to date")) {
753 status = REF_STATUS_UPTODATE;
6a83d902 754 FREE_AND_NULL(msg);
d2e73c6f
SR
755 }
756 else if (!strcmp(msg, "non-fast forward")) {
757 status = REF_STATUS_REJECT_NONFASTFORWARD;
6a83d902 758 FREE_AND_NULL(msg);
d2e73c6f 759 }
dbfeddb1
CR
760 else if (!strcmp(msg, "already exists")) {
761 status = REF_STATUS_REJECT_ALREADY_EXISTS;
6a83d902 762 FREE_AND_NULL(msg);
dbfeddb1 763 }
75e5c0dc
JH
764 else if (!strcmp(msg, "fetch first")) {
765 status = REF_STATUS_REJECT_FETCH_FIRST;
6a83d902 766 FREE_AND_NULL(msg);
75e5c0dc
JH
767 }
768 else if (!strcmp(msg, "needs force")) {
769 status = REF_STATUS_REJECT_NEEDS_FORCE;
6a83d902 770 FREE_AND_NULL(msg);
75e5c0dc 771 }
631b5ef2
JH
772 else if (!strcmp(msg, "stale info")) {
773 status = REF_STATUS_REJECT_STALE;
6a83d902 774 FREE_AND_NULL(msg);
631b5ef2 775 }
f9e3c6be
FC
776 else if (!strcmp(msg, "forced update")) {
777 forced = 1;
6a83d902 778 FREE_AND_NULL(msg);
f9e3c6be 779 }
d2e73c6f
SR
780 }
781
782 if (*ref)
783 *ref = find_ref_by_name(*ref, refname);
784 if (!*ref)
785 *ref = find_ref_by_name(remote_refs, refname);
786 if (!*ref) {
6b5b309f 787 warning(_("helper reported unexpected status of %s"), refname);
664059fb 788 return 1;
d2e73c6f
SR
789 }
790
791 if ((*ref)->status != REF_STATUS_NONE) {
792 /*
793 * Earlier, the ref was marked not to be pushed, so ignore the ref
794 * status reported by the remote helper if the latter is 'no match'.
795 */
796 if (status == REF_STATUS_NONE)
664059fb 797 return 1;
d2e73c6f
SR
798 }
799
800 (*ref)->status = status;
cf31f70c 801 (*ref)->forced_update |= forced;
d2e73c6f 802 (*ref)->remote_status = msg;
126aac5c 803 return !(status == REF_STATUS_OK);
d2e73c6f
SR
804}
805
0551a06c 806static int push_update_refs_status(struct helper_data *data,
5a75353f
FC
807 struct ref *remote_refs,
808 int flags)
d2e73c6f
SR
809{
810 struct strbuf buf = STRBUF_INIT;
811 struct ref *ref = remote_refs;
0551a06c
FC
812 int ret = 0;
813
d2e73c6f 814 for (;;) {
664059fb
FC
815 char *private;
816
0551a06c
FC
817 if (recvline(data, &buf)) {
818 ret = 1;
819 break;
820 }
821
d2e73c6f
SR
822 if (!buf.len)
823 break;
824
664059fb
FC
825 if (push_update_ref_status(&buf, &ref, remote_refs))
826 continue;
827
57f32ac2 828 if (flags & TRANSPORT_PUSH_DRY_RUN || !data->rs.nr || data->no_private_update)
664059fb
FC
829 continue;
830
831 /* propagate back the update to the remote namespace */
d000414e 832 private = apply_refspecs(&data->rs, ref->name);
664059fb
FC
833 if (!private)
834 continue;
ae077771 835 update_ref("update by helper", private, &ref->new_oid, NULL,
836 0, 0);
664059fb 837 free(private);
d2e73c6f
SR
838 }
839 strbuf_release(&buf);
0551a06c 840 return ret;
d2e73c6f
SR
841}
842
30261094
DB
843static void set_common_push_options(struct transport *transport,
844 const char *name, int flags)
845{
846 if (flags & TRANSPORT_PUSH_DRY_RUN) {
847 if (set_helper_option(transport, "dry-run", "true") != 0)
6b5b309f 848 die(_("helper %s does not support dry-run"), name);
30261094
DB
849 } else if (flags & TRANSPORT_PUSH_CERT_ALWAYS) {
850 if (set_helper_option(transport, TRANS_OPT_PUSH_CERT, "true") != 0)
6b5b309f 851 die(_("helper %s does not support --signed"), name);
30261094
DB
852 } else if (flags & TRANSPORT_PUSH_CERT_IF_ASKED) {
853 if (set_helper_option(transport, TRANS_OPT_PUSH_CERT, "if-asked") != 0)
6b5b309f 854 die(_("helper %s does not support --signed=if-asked"), name);
30261094 855 }
438fc684
SB
856
857 if (flags & TRANSPORT_PUSH_OPTIONS) {
858 struct string_list_item *item;
859 for_each_string_list_item(item, transport->push_options)
860 if (set_helper_option(transport, "push-option", item->string) != 0)
6b5b309f 861 die(_("helper %s does not support 'push-option'"), name);
438fc684 862 }
30261094
DB
863}
864
73b49a75 865static int push_refs_with_push(struct transport *transport,
05c1eb10 866 struct ref *remote_refs, int flags)
ae4efe19
SP
867{
868 int force_all = flags & TRANSPORT_PUSH_FORCE;
869 int mirror = flags & TRANSPORT_PUSH_MIRROR;
3bca1e7f 870 int atomic = flags & TRANSPORT_PUSH_ATOMIC;
ae4efe19
SP
871 struct helper_data *data = transport->data;
872 struct strbuf buf = STRBUF_INIT;
ae4efe19 873 struct ref *ref;
05c1eb10
JH
874 struct string_list cas_options = STRING_LIST_INIT_DUP;
875 struct string_list_item *cas_option;
ae4efe19 876
c0aa335c 877 get_helper(transport);
ae4efe19
SP
878 if (!data->push)
879 return 1;
880
881 for (ref = remote_refs; ref; ref = ref->next) {
20e8b465 882 if (!ref->peer_ref && !mirror)
ae4efe19
SP
883 continue;
884
20e8b465
TRC
885 /* Check for statuses set by set_ref_status_for_push() */
886 switch (ref->status) {
887 case REF_STATUS_REJECT_NONFASTFORWARD:
631b5ef2 888 case REF_STATUS_REJECT_STALE:
dbfeddb1 889 case REF_STATUS_REJECT_ALREADY_EXISTS:
3bca1e7f
ES
890 if (atomic) {
891 string_list_clear(&cas_options, 0);
892 return 0;
893 } else
894 continue;
20e8b465 895 case REF_STATUS_UPTODATE:
ae4efe19 896 continue;
20e8b465
TRC
897 default:
898 ; /* do nothing */
ae4efe19
SP
899 }
900
901 if (force_all)
902 ref->force = 1;
903
904 strbuf_addstr(&buf, "push ");
905 if (!ref->deletion) {
906 if (ref->force)
907 strbuf_addch(&buf, '+');
908 if (ref->peer_ref)
909 strbuf_addstr(&buf, ref->peer_ref->name);
910 else
f4e54d02 911 strbuf_addstr(&buf, oid_to_hex(&ref->new_oid));
ae4efe19
SP
912 }
913 strbuf_addch(&buf, ':');
914 strbuf_addstr(&buf, ref->name);
915 strbuf_addch(&buf, '\n');
05c1eb10
JH
916
917 /*
918 * The "--force-with-lease" options without explicit
919 * values to expect have already been expanded into
f4e54d02 920 * the ref->old_oid_expect[] field; we can ignore
05c1eb10
JH
921 * transport->smart_options->cas altogether and instead
922 * can enumerate them from the refs.
923 */
924 if (ref->expect_old_sha1) {
925 struct strbuf cas = STRBUF_INIT;
926 strbuf_addf(&cas, "%s:%s",
f4e54d02 927 ref->name, oid_to_hex(&ref->old_oid_expect));
176cb979
RS
928 string_list_append_nodup(&cas_options,
929 strbuf_detach(&cas, NULL));
05c1eb10 930 }
ae4efe19 931 }
05c1eb10
JH
932 if (buf.len == 0) {
933 string_list_clear(&cas_options, 0);
d8f67d20 934 return 0;
05c1eb10 935 }
ae4efe19 936
05c1eb10
JH
937 for_each_string_list_item(cas_option, &cas_options)
938 set_helper_option(transport, "cas", cas_option->string);
30261094 939 set_common_push_options(transport, data->name, flags);
ae4efe19
SP
940
941 strbuf_addch(&buf, '\n');
bf3c523c 942 sendline(data, &buf);
ae4efe19 943 strbuf_release(&buf);
176cb979 944 string_list_clear(&cas_options, 0);
d2e73c6f 945
0551a06c 946 return push_update_refs_status(data, remote_refs, flags);
ae4efe19
SP
947}
948
73b49a75
SR
949static int push_refs_with_export(struct transport *transport,
950 struct ref *remote_refs, int flags)
951{
952 struct ref *ref;
953 struct child_process *helper, exporter;
954 struct helper_data *data = transport->data;
d98c8153 955 struct string_list revlist_args = STRING_LIST_INIT_DUP;
73b49a75
SR
956 struct strbuf buf = STRBUF_INIT;
957
57f32ac2 958 if (!data->rs.nr)
6b5b309f 959 die(_("remote-helper doesn't support push; refspec needed"));
21610d82 960
30261094 961 set_common_push_options(transport, data->name, flags);
510fa6f5
FC
962 if (flags & TRANSPORT_PUSH_FORCE) {
963 if (set_helper_option(transport, "force", "true") != 0)
6b5b309f 964 warning(_("helper %s does not support 'force'"), data->name);
510fa6f5
FC
965 }
966
73b49a75
SR
967 helper = get_helper(transport);
968
969 write_constant(helper->in, "export\n");
970
73b49a75
SR
971 for (ref = remote_refs; ref; ref = ref->next) {
972 char *private;
27912a03 973 struct object_id oid;
73b49a75 974
d000414e 975 private = apply_refspecs(&data->rs, ref->name);
e82caf38 976 if (private && !get_oid(private, &oid)) {
73b49a75 977 strbuf_addf(&buf, "^%s", private);
176cb979
RS
978 string_list_append_nodup(&revlist_args,
979 strbuf_detach(&buf, NULL));
27912a03 980 oidcpy(&ref->old_oid, &oid);
73b49a75 981 }
2faa1527 982 free(private);
73b49a75 983
67c9c782 984 if (ref->peer_ref) {
d98c8153 985 if (strcmp(ref->name, ref->peer_ref->name)) {
f3d03763
FC
986 if (!ref->deletion) {
987 const char *name;
988 int flag;
989
990 /* Follow symbolic refs (mainly for HEAD). */
49e61479 991 name = resolve_ref_unsafe(ref->peer_ref->name,
992 RESOLVE_REF_READING,
993 &oid, &flag);
f3d03763
FC
994 if (!name || !(flag & REF_ISSYMREF))
995 name = ref->peer_ref->name;
9193f742 996
f3d03763
FC
997 strbuf_addf(&buf, "%s:%s", name, ref->name);
998 } else
999 strbuf_addf(&buf, ":%s", ref->name);
9193f742 1000
d98c8153
FC
1001 string_list_append(&revlist_args, "--refspec");
1002 string_list_append(&revlist_args, buf.buf);
1003 strbuf_release(&buf);
1004 }
f3d03763
FC
1005 if (!ref->deletion)
1006 string_list_append(&revlist_args, ref->peer_ref->name);
67c9c782 1007 }
73b49a75
SR
1008 }
1009
a515ebe9 1010 if (get_exporter(transport, &exporter, &revlist_args))
6b5b309f 1011 die(_("couldn't run fast-export"));
73b49a75 1012
d98c8153
FC
1013 string_list_clear(&revlist_args, 1);
1014
cc567322 1015 if (finish_command(&exporter))
6b5b309f 1016 die(_("error while running fast-export"));
3994e64d
FC
1017 if (push_update_refs_status(data, remote_refs, flags))
1018 return 1;
1019
1020 if (data->export_marks) {
1021 strbuf_addf(&buf, "%s.tmp", data->export_marks);
1022 rename(buf.buf, data->export_marks);
1023 strbuf_release(&buf);
1024 }
1025
1026 return 0;
73b49a75
SR
1027}
1028
1029static int push_refs(struct transport *transport,
1030 struct ref *remote_refs, int flags)
1031{
1032 struct helper_data *data = transport->data;
1033
1034 if (process_connect(transport, 1)) {
1035 do_take_over(transport);
e967ca38 1036 return transport->vtable->push_refs(transport, remote_refs, flags);
73b49a75
SR
1037 }
1038
1039 if (!remote_refs) {
6b5b309f
NTND
1040 fprintf(stderr,
1041 _("No refs in common and none specified; doing nothing.\n"
1042 "Perhaps you should specify a branch such as 'master'.\n"));
73b49a75
SR
1043 return 0;
1044 }
1045
1046 if (data->push)
1047 return push_refs_with_push(transport, remote_refs, flags);
1048
1049 if (data->export)
1050 return push_refs_with_export(transport, remote_refs, flags);
1051
1052 return -1;
1053}
1054
1055
3b335762
NTND
1056static int has_attribute(const char *attrs, const char *attr)
1057{
f8ec9167
DB
1058 int len;
1059 if (!attrs)
1060 return 0;
1061
1062 len = strlen(attr);
1063 for (;;) {
1064 const char *space = strchrnul(attrs, ' ');
1065 if (len == space - attrs && !strncmp(attrs, attr, len))
1066 return 1;
1067 if (!*space)
1068 return 0;
1069 attrs = space + 1;
1070 }
1071}
1072
834cf34b
BW
1073static struct ref *get_refs_list(struct transport *transport, int for_push,
1074 const struct argv_array *ref_prefixes)
ac3fda82
JT
1075{
1076 get_helper(transport);
1077
1078 if (process_connect(transport, for_push)) {
1079 do_take_over(transport);
1080 return transport->vtable->get_refs_list(transport, for_push, ref_prefixes);
1081 }
1082
1083 return get_refs_list_using_list(transport, for_push);
1084}
1085
1086static struct ref *get_refs_list_using_list(struct transport *transport,
1087 int for_push)
6eb996b5 1088{
292ce46b 1089 struct helper_data *data = transport->data;
6eb996b5
DB
1090 struct child_process *helper;
1091 struct ref *ret = NULL;
1092 struct ref **tail = &ret;
1093 struct ref *posn;
1094 struct strbuf buf = STRBUF_INIT;
6eb996b5 1095
ac3fda82 1096 data->get_refs_list_called = 1;
6eb996b5 1097 helper = get_helper(transport);
2d14d65c 1098
ae4efe19
SP
1099 if (data->push && for_push)
1100 write_str_in_full(helper->in, "list for-push\n");
1101 else
1102 write_str_in_full(helper->in, "list\n");
6eb996b5 1103
6eb996b5
DB
1104 while (1) {
1105 char *eov, *eon;
5931b33e
FC
1106 if (recvline(data, &buf))
1107 exit(128);
6eb996b5
DB
1108
1109 if (!*buf.buf)
1110 break;
1111
1112 eov = strchr(buf.buf, ' ');
1113 if (!eov)
6b5b309f 1114 die(_("malformed response in ref list: %s"), buf.buf);
6eb996b5
DB
1115 eon = strchr(eov + 1, ' ');
1116 *eov = '\0';
1117 if (eon)
1118 *eon = '\0';
1119 *tail = alloc_ref(eov + 1);
1120 if (buf.buf[0] == '@')
1121 (*tail)->symref = xstrdup(buf.buf + 1);
1122 else if (buf.buf[0] != '?')
f4e54d02 1123 get_oid_hex(buf.buf, &(*tail)->old_oid);
f8ec9167
DB
1124 if (eon) {
1125 if (has_attribute(eon + 1, "unchanged")) {
1126 (*tail)->status |= REF_STATUS_UPTODATE;
34c290a6 1127 if (read_ref((*tail)->name, &(*tail)->old_oid) < 0)
1a07e59c 1128 die(_("could not read ref %s"),
ae25fd39 1129 (*tail)->name);
f8ec9167
DB
1130 }
1131 }
6eb996b5
DB
1132 tail = &((*tail)->next);
1133 }
bf3c523c
IL
1134 if (debug)
1135 fprintf(stderr, "Debug: Read ref listing.\n");
6eb996b5
DB
1136 strbuf_release(&buf);
1137
1138 for (posn = ret; posn; posn = posn->next)
1139 resolve_remote_symref(posn, ret);
1140
1141 return ret;
1142}
1143
e967ca38
JT
1144static struct transport_vtable vtable = {
1145 set_helper_option,
1146 get_refs_list,
1147 fetch,
1148 push_refs,
1149 connect_helper,
1150 release_helper
1151};
1152
c9e388bb 1153int transport_helper_init(struct transport *transport, const char *name)
6eb996b5 1154{
92e25b6b 1155 struct helper_data *data = xcalloc(1, sizeof(*data));
c9e388bb 1156 data->name = name;
6eb996b5 1157
a5adaced
JK
1158 transport_check_allowed(name);
1159
bf3c523c
IL
1160 if (getenv("GIT_TRANSPORT_HELPER_DEBUG"))
1161 debug = 1;
1162
6eb996b5 1163 transport->data = data;
e967ca38 1164 transport->vtable = &vtable;
61b075bd 1165 transport->smart_options = &(data->transport_options);
6eb996b5
DB
1166 return 0;
1167}
419f37db
IL
1168
1169/*
1170 * Linux pipes can buffer 65536 bytes at once (and most platforms can
1171 * buffer less), so attempt reads and writes with up to that size.
1172 */
1173#define BUFFERSIZE 65536
1174/* This should be enough to hold debugging message. */
1175#define PBUFFERSIZE 8192
1176
1177/* Print bidirectional transfer loop debug message. */
4621085b 1178__attribute__((format (printf, 1, 2)))
419f37db
IL
1179static void transfer_debug(const char *fmt, ...)
1180{
6cdf8a79
1181 /*
1182 * NEEDSWORK: This function is sometimes used from multiple threads, and
1183 * we end up using debug_enabled racily. That "should not matter" since
1184 * we always write the same value, but it's still wrong. This function
1185 * is listed in .tsan-suppressions for the time being.
1186 */
1187
419f37db
IL
1188 va_list args;
1189 char msgbuf[PBUFFERSIZE];
1190 static int debug_enabled = -1;
1191
1192 if (debug_enabled < 0)
1193 debug_enabled = getenv("GIT_TRANSLOOP_DEBUG") ? 1 : 0;
1194 if (!debug_enabled)
1195 return;
1196
1197 va_start(args, fmt);
1198 vsnprintf(msgbuf, PBUFFERSIZE, fmt, args);
1199 va_end(args);
1200 fprintf(stderr, "Transfer loop debugging: %s\n", msgbuf);
1201}
1202
1203/* Stream state: More data may be coming in this direction. */
2e3a16b2 1204#define SSTATE_TRANSFERRING 0
419f37db
IL
1205/*
1206 * Stream state: No more data coming in this direction, flushing rest of
1207 * data.
1208 */
1209#define SSTATE_FLUSHING 1
1210/* Stream state: Transfer in this direction finished. */
1211#define SSTATE_FINISHED 2
1212
2e3a16b2 1213#define STATE_NEEDS_READING(state) ((state) <= SSTATE_TRANSFERRING)
419f37db
IL
1214#define STATE_NEEDS_WRITING(state) ((state) <= SSTATE_FLUSHING)
1215#define STATE_NEEDS_CLOSING(state) ((state) == SSTATE_FLUSHING)
1216
1217/* Unidirectional transfer. */
1218struct unidirectional_transfer {
1219 /* Source */
1220 int src;
1221 /* Destination */
1222 int dest;
1223 /* Is source socket? */
1224 int src_is_sock;
1225 /* Is destination socket? */
1226 int dest_is_sock;
41ccfdd9 1227 /* Transfer state (TRANSFERRING/FLUSHING/FINISHED) */
419f37db
IL
1228 int state;
1229 /* Buffer. */
1230 char buf[BUFFERSIZE];
1231 /* Buffer used. */
1232 size_t bufuse;
1233 /* Name of source. */
1234 const char *src_name;
1235 /* Name of destination. */
1236 const char *dest_name;
1237};
1238
1239/* Closes the target (for writing) if transfer has finished. */
1240static void udt_close_if_finished(struct unidirectional_transfer *t)
1241{
1242 if (STATE_NEEDS_CLOSING(t->state) && !t->bufuse) {
1243 t->state = SSTATE_FINISHED;
1244 if (t->dest_is_sock)
1245 shutdown(t->dest, SHUT_WR);
1246 else
1247 close(t->dest);
1248 transfer_debug("Closed %s.", t->dest_name);
1249 }
1250}
1251
1252/*
832c0e5e 1253 * Tries to read data from source into buffer. If buffer is full,
419f37db
IL
1254 * no data is read. Returns 0 on success, -1 on error.
1255 */
1256static int udt_do_read(struct unidirectional_transfer *t)
1257{
1258 ssize_t bytes;
1259
1260 if (t->bufuse == BUFFERSIZE)
1261 return 0; /* No space for more. */
1262
1263 transfer_debug("%s is readable", t->src_name);
c14e5a1a 1264 bytes = xread(t->src, t->buf + t->bufuse, BUFFERSIZE - t->bufuse);
d4c81368 1265 if (bytes < 0) {
6b5b309f 1266 error_errno(_("read(%s) failed"), t->src_name);
419f37db
IL
1267 return -1;
1268 } else if (bytes == 0) {
1269 transfer_debug("%s EOF (with %i bytes in buffer)",
4621085b 1270 t->src_name, (int)t->bufuse);
419f37db
IL
1271 t->state = SSTATE_FLUSHING;
1272 } else if (bytes > 0) {
1273 t->bufuse += bytes;
1274 transfer_debug("Read %i bytes from %s (buffer now at %i)",
1275 (int)bytes, t->src_name, (int)t->bufuse);
1276 }
1277 return 0;
1278}
1279
1280/* Tries to write data from buffer into destination. If buffer is empty,
1281 * no data is written. Returns 0 on success, -1 on error.
1282 */
1283static int udt_do_write(struct unidirectional_transfer *t)
1284{
803dbdb9 1285 ssize_t bytes;
419f37db
IL
1286
1287 if (t->bufuse == 0)
1288 return 0; /* Nothing to write. */
1289
1290 transfer_debug("%s is writable", t->dest_name);
7edc02f4 1291 bytes = xwrite(t->dest, t->buf, t->bufuse);
d4c81368 1292 if (bytes < 0) {
6b5b309f 1293 error_errno(_("write(%s) failed"), t->dest_name);
419f37db
IL
1294 return -1;
1295 } else if (bytes > 0) {
1296 t->bufuse -= bytes;
1297 if (t->bufuse)
1298 memmove(t->buf, t->buf + bytes, t->bufuse);
1299 transfer_debug("Wrote %i bytes to %s (buffer now at %i)",
1300 (int)bytes, t->dest_name, (int)t->bufuse);
1301 }
1302 return 0;
1303}
1304
1305
1306/* State of bidirectional transfer loop. */
1307struct bidirectional_transfer_state {
1308 /* Direction from program to git. */
1309 struct unidirectional_transfer ptg;
1310 /* Direction from git to program. */
1311 struct unidirectional_transfer gtp;
1312};
1313
1314static void *udt_copy_task_routine(void *udt)
1315{
1316 struct unidirectional_transfer *t = (struct unidirectional_transfer *)udt;
1317 while (t->state != SSTATE_FINISHED) {
1318 if (STATE_NEEDS_READING(t->state))
1319 if (udt_do_read(t))
1320 return NULL;
1321 if (STATE_NEEDS_WRITING(t->state))
1322 if (udt_do_write(t))
1323 return NULL;
1324 if (STATE_NEEDS_CLOSING(t->state))
1325 udt_close_if_finished(t);
1326 }
1327 return udt; /* Just some non-NULL value. */
1328}
1329
1330#ifndef NO_PTHREADS
1331
1332/*
98e023de 1333 * Join thread, with appropriate errors on failure. Name is name for the
419f37db
IL
1334 * thread (for error messages). Returns 0 on success, 1 on failure.
1335 */
1336static int tloop_join(pthread_t thread, const char *name)
1337{
1338 int err;
1339 void *tret;
1340 err = pthread_join(thread, &tret);
1341 if (!tret) {
6b5b309f 1342 error(_("%s thread failed"), name);
419f37db
IL
1343 return 1;
1344 }
1345 if (err) {
6b5b309f 1346 error(_("%s thread failed to join: %s"), name, strerror(err));
419f37db
IL
1347 return 1;
1348 }
1349 return 0;
1350}
1351
1352/*
1353 * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1354 * -1 on failure.
1355 */
1356static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1357{
1358 pthread_t gtp_thread;
1359 pthread_t ptg_thread;
1360 int err;
1361 int ret = 0;
1362 err = pthread_create(&gtp_thread, NULL, udt_copy_task_routine,
1363 &s->gtp);
1364 if (err)
6b5b309f 1365 die(_("can't start thread for copying data: %s"), strerror(err));
419f37db
IL
1366 err = pthread_create(&ptg_thread, NULL, udt_copy_task_routine,
1367 &s->ptg);
1368 if (err)
6b5b309f 1369 die(_("can't start thread for copying data: %s"), strerror(err));
419f37db
IL
1370
1371 ret |= tloop_join(gtp_thread, "Git to program copy");
1372 ret |= tloop_join(ptg_thread, "Program to git copy");
1373 return ret;
1374}
1375#else
1376
1377/* Close the source and target (for writing) for transfer. */
1378static void udt_kill_transfer(struct unidirectional_transfer *t)
1379{
1380 t->state = SSTATE_FINISHED;
1381 /*
1382 * Socket read end left open isn't a disaster if nobody
1383 * attempts to read from it (mingw compat headers do not
1384 * have SHUT_RD)...
1385 *
1386 * We can't fully close the socket since otherwise gtp
1387 * task would first close the socket it sends data to
1388 * while closing the ptg file descriptors.
1389 */
1390 if (!t->src_is_sock)
1391 close(t->src);
1392 if (t->dest_is_sock)
1393 shutdown(t->dest, SHUT_WR);
1394 else
1395 close(t->dest);
1396}
1397
1398/*
98e023de 1399 * Join process, with appropriate errors on failure. Name is name for the
419f37db
IL
1400 * process (for error messages). Returns 0 on success, 1 on failure.
1401 */
1402static int tloop_join(pid_t pid, const char *name)
1403{
1404 int tret;
1405 if (waitpid(pid, &tret, 0) < 0) {
6b5b309f 1406 error_errno(_("%s process failed to wait"), name);
419f37db
IL
1407 return 1;
1408 }
1409 if (!WIFEXITED(tret) || WEXITSTATUS(tret)) {
6b5b309f 1410 error(_("%s process failed"), name);
419f37db
IL
1411 return 1;
1412 }
1413 return 0;
1414}
1415
1416/*
1417 * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1418 * -1 on failure.
1419 */
1420static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1421{
1422 pid_t pid1, pid2;
1423 int ret = 0;
1424
1425 /* Fork thread #1: git to program. */
1426 pid1 = fork();
1427 if (pid1 < 0)
6b5b309f 1428 die_errno(_("can't start thread for copying data"));
419f37db
IL
1429 else if (pid1 == 0) {
1430 udt_kill_transfer(&s->ptg);
1431 exit(udt_copy_task_routine(&s->gtp) ? 0 : 1);
1432 }
1433
1434 /* Fork thread #2: program to git. */
1435 pid2 = fork();
1436 if (pid2 < 0)
6b5b309f 1437 die_errno(_("can't start thread for copying data"));
419f37db
IL
1438 else if (pid2 == 0) {
1439 udt_kill_transfer(&s->gtp);
1440 exit(udt_copy_task_routine(&s->ptg) ? 0 : 1);
1441 }
1442
1443 /*
1444 * Close both streams in parent as to not interfere with
1445 * end of file detection and wait for both tasks to finish.
1446 */
1447 udt_kill_transfer(&s->gtp);
1448 udt_kill_transfer(&s->ptg);
1449 ret |= tloop_join(pid1, "Git to program copy");
1450 ret |= tloop_join(pid2, "Program to git copy");
1451 return ret;
1452}
1453#endif
1454
1455/*
1456 * Copies data from stdin to output and from input to stdout simultaneously.
1457 * Additionally filtering through given filter. If filter is NULL, uses
1458 * identity filter.
1459 */
1460int bidirectional_transfer_loop(int input, int output)
1461{
1462 struct bidirectional_transfer_state state;
1463
1464 /* Fill the state fields. */
1465 state.ptg.src = input;
1466 state.ptg.dest = 1;
1467 state.ptg.src_is_sock = (input == output);
1468 state.ptg.dest_is_sock = 0;
2e3a16b2 1469 state.ptg.state = SSTATE_TRANSFERRING;
419f37db
IL
1470 state.ptg.bufuse = 0;
1471 state.ptg.src_name = "remote input";
1472 state.ptg.dest_name = "stdout";
1473
1474 state.gtp.src = 0;
1475 state.gtp.dest = output;
1476 state.gtp.src_is_sock = 0;
1477 state.gtp.dest_is_sock = (input == output);
2e3a16b2 1478 state.gtp.state = SSTATE_TRANSFERRING;
419f37db
IL
1479 state.gtp.bufuse = 0;
1480 state.gtp.src_name = "stdin";
1481 state.gtp.dest_name = "remote output";
1482
1483 return tloop_spawnwait_tasks(&state);
1484}