t3430: add conflicting commit
[git] / send-pack.c
1 #include "builtin.h"
2 #include "config.h"
3 #include "commit.h"
4 #include "refs.h"
5 #include "pkt-line.h"
6 #include "sideband.h"
7 #include "run-command.h"
8 #include "remote.h"
9 #include "connect.h"
10 #include "send-pack.h"
11 #include "quote.h"
12 #include "transport.h"
13 #include "version.h"
14 #include "sha1-array.h"
15 #include "gpg-interface.h"
16 #include "cache.h"
17
18 int option_parse_push_signed(const struct option *opt,
19                              const char *arg, int unset)
20 {
21         if (unset) {
22                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_NEVER;
23                 return 0;
24         }
25         switch (git_parse_maybe_bool(arg)) {
26         case 1:
27                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_ALWAYS;
28                 return 0;
29         case 0:
30                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_NEVER;
31                 return 0;
32         }
33         if (!strcasecmp("if-asked", arg)) {
34                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_IF_ASKED;
35                 return 0;
36         }
37         die("bad %s argument: %s", opt->long_name, arg);
38 }
39
40 static void feed_object(const struct object_id *oid, FILE *fh, int negative)
41 {
42         if (negative && !has_sha1_file(oid->hash))
43                 return;
44
45         if (negative)
46                 putc('^', fh);
47         fputs(oid_to_hex(oid), fh);
48         putc('\n', fh);
49 }
50
51 /*
52  * Make a pack stream and spit it out into file descriptor fd
53  */
54 static int pack_objects(int fd, struct ref *refs, struct oid_array *extra, struct send_pack_args *args)
55 {
56         /*
57          * The child becomes pack-objects --revs; we feed
58          * the revision parameters to it via its stdin and
59          * let its stdout go back to the other end.
60          */
61         struct child_process po = CHILD_PROCESS_INIT;
62         FILE *po_in;
63         int i;
64         int rc;
65
66         argv_array_push(&po.args, "pack-objects");
67         argv_array_push(&po.args, "--all-progress-implied");
68         argv_array_push(&po.args, "--revs");
69         argv_array_push(&po.args, "--stdout");
70         if (args->use_thin_pack)
71                 argv_array_push(&po.args, "--thin");
72         if (args->use_ofs_delta)
73                 argv_array_push(&po.args, "--delta-base-offset");
74         if (args->quiet || !args->progress)
75                 argv_array_push(&po.args, "-q");
76         if (args->progress)
77                 argv_array_push(&po.args, "--progress");
78         if (is_repository_shallow())
79                 argv_array_push(&po.args, "--shallow");
80         po.in = -1;
81         po.out = args->stateless_rpc ? -1 : fd;
82         po.git_cmd = 1;
83         if (start_command(&po))
84                 die_errno("git pack-objects failed");
85
86         /*
87          * We feed the pack-objects we just spawned with revision
88          * parameters by writing to the pipe.
89          */
90         po_in = xfdopen(po.in, "w");
91         for (i = 0; i < extra->nr; i++)
92                 feed_object(&extra->oid[i], po_in, 1);
93
94         while (refs) {
95                 if (!is_null_oid(&refs->old_oid))
96                         feed_object(&refs->old_oid, po_in, 1);
97                 if (!is_null_oid(&refs->new_oid))
98                         feed_object(&refs->new_oid, po_in, 0);
99                 refs = refs->next;
100         }
101
102         fflush(po_in);
103         if (ferror(po_in))
104                 die_errno("error writing to pack-objects");
105         fclose(po_in);
106
107         if (args->stateless_rpc) {
108                 char *buf = xmalloc(LARGE_PACKET_MAX);
109                 while (1) {
110                         ssize_t n = xread(po.out, buf, LARGE_PACKET_MAX);
111                         if (n <= 0)
112                                 break;
113                         send_sideband(fd, -1, buf, n, LARGE_PACKET_MAX);
114                 }
115                 free(buf);
116                 close(po.out);
117                 po.out = -1;
118         }
119
120         rc = finish_command(&po);
121         if (rc) {
122                 /*
123                  * For a normal non-zero exit, we assume pack-objects wrote
124                  * something useful to stderr. For death by signal, though,
125                  * we should mention it to the user. The exception is SIGPIPE
126                  * (141), because that's a normal occurrence if the remote end
127                  * hangs up (and we'll report that by trying to read the unpack
128                  * status).
129                  */
130                 if (rc > 128 && rc != 141)
131                         error("pack-objects died of signal %d", rc - 128);
132                 return -1;
133         }
134         return 0;
135 }
136
137 static int receive_unpack_status(int in)
138 {
139         const char *line = packet_read_line(in, NULL);
140         if (!line)
141                 return error(_("unexpected flush packet while reading remote unpack status"));
142         if (!skip_prefix(line, "unpack ", &line))
143                 return error(_("unable to parse remote unpack status: %s"), line);
144         if (strcmp(line, "ok"))
145                 return error(_("remote unpack failed: %s"), line);
146         return 0;
147 }
148
149 static int receive_status(int in, struct ref *refs)
150 {
151         struct ref *hint;
152         int ret;
153
154         hint = NULL;
155         ret = receive_unpack_status(in);
156         while (1) {
157                 char *refname;
158                 char *msg;
159                 char *line = packet_read_line(in, NULL);
160                 if (!line)
161                         break;
162                 if (!starts_with(line, "ok ") && !starts_with(line, "ng ")) {
163                         error("invalid ref status from remote: %s", line);
164                         ret = -1;
165                         break;
166                 }
167
168                 refname = line + 3;
169                 msg = strchr(refname, ' ');
170                 if (msg)
171                         *msg++ = '\0';
172
173                 /* first try searching at our hint, falling back to all refs */
174                 if (hint)
175                         hint = find_ref_by_name(hint, refname);
176                 if (!hint)
177                         hint = find_ref_by_name(refs, refname);
178                 if (!hint) {
179                         warning("remote reported status on unknown ref: %s",
180                                         refname);
181                         continue;
182                 }
183                 if (hint->status != REF_STATUS_EXPECTING_REPORT) {
184                         warning("remote reported status on unexpected ref: %s",
185                                         refname);
186                         continue;
187                 }
188
189                 if (line[0] == 'o' && line[1] == 'k')
190                         hint->status = REF_STATUS_OK;
191                 else {
192                         hint->status = REF_STATUS_REMOTE_REJECT;
193                         ret = -1;
194                 }
195                 hint->remote_status = xstrdup_or_null(msg);
196                 /* start our next search from the next ref */
197                 hint = hint->next;
198         }
199         return ret;
200 }
201
202 static int sideband_demux(int in, int out, void *data)
203 {
204         int *fd = data, ret;
205 #ifdef NO_PTHREADS
206         close(fd[1]);
207 #endif
208         ret = recv_sideband("send-pack", fd[0], out);
209         close(out);
210         return ret;
211 }
212
213 static int advertise_shallow_grafts_cb(const struct commit_graft *graft, void *cb)
214 {
215         struct strbuf *sb = cb;
216         if (graft->nr_parent == -1)
217                 packet_buf_write(sb, "shallow %s\n", oid_to_hex(&graft->oid));
218         return 0;
219 }
220
221 static void advertise_shallow_grafts_buf(struct strbuf *sb)
222 {
223         if (!is_repository_shallow())
224                 return;
225         for_each_commit_graft(advertise_shallow_grafts_cb, sb);
226 }
227
228 #define CHECK_REF_NO_PUSH -1
229 #define CHECK_REF_STATUS_REJECTED -2
230 #define CHECK_REF_UPTODATE -3
231 static int check_to_send_update(const struct ref *ref, const struct send_pack_args *args)
232 {
233         if (!ref->peer_ref && !args->send_mirror)
234                 return CHECK_REF_NO_PUSH;
235
236         /* Check for statuses set by set_ref_status_for_push() */
237         switch (ref->status) {
238         case REF_STATUS_REJECT_NONFASTFORWARD:
239         case REF_STATUS_REJECT_ALREADY_EXISTS:
240         case REF_STATUS_REJECT_FETCH_FIRST:
241         case REF_STATUS_REJECT_NEEDS_FORCE:
242         case REF_STATUS_REJECT_STALE:
243         case REF_STATUS_REJECT_NODELETE:
244                 return CHECK_REF_STATUS_REJECTED;
245         case REF_STATUS_UPTODATE:
246                 return CHECK_REF_UPTODATE;
247         default:
248                 return 0;
249         }
250 }
251
252 /*
253  * the beginning of the next line, or the end of buffer.
254  *
255  * NEEDSWORK: perhaps move this to git-compat-util.h or somewhere and
256  * convert many similar uses found by "git grep -A4 memchr".
257  */
258 static const char *next_line(const char *line, size_t len)
259 {
260         const char *nl = memchr(line, '\n', len);
261         if (!nl)
262                 return line + len; /* incomplete line */
263         return nl + 1;
264 }
265
266 static int generate_push_cert(struct strbuf *req_buf,
267                               const struct ref *remote_refs,
268                               struct send_pack_args *args,
269                               const char *cap_string,
270                               const char *push_cert_nonce)
271 {
272         const struct ref *ref;
273         struct string_list_item *item;
274         char *signing_key = xstrdup(get_signing_key());
275         const char *cp, *np;
276         struct strbuf cert = STRBUF_INIT;
277         int update_seen = 0;
278
279         strbuf_addstr(&cert, "certificate version 0.1\n");
280         strbuf_addf(&cert, "pusher %s ", signing_key);
281         datestamp(&cert);
282         strbuf_addch(&cert, '\n');
283         if (args->url && *args->url) {
284                 char *anon_url = transport_anonymize_url(args->url);
285                 strbuf_addf(&cert, "pushee %s\n", anon_url);
286                 free(anon_url);
287         }
288         if (push_cert_nonce[0])
289                 strbuf_addf(&cert, "nonce %s\n", push_cert_nonce);
290         if (args->push_options)
291                 for_each_string_list_item(item, args->push_options)
292                         strbuf_addf(&cert, "push-option %s\n", item->string);
293         strbuf_addstr(&cert, "\n");
294
295         for (ref = remote_refs; ref; ref = ref->next) {
296                 if (check_to_send_update(ref, args) < 0)
297                         continue;
298                 update_seen = 1;
299                 strbuf_addf(&cert, "%s %s %s\n",
300                             oid_to_hex(&ref->old_oid),
301                             oid_to_hex(&ref->new_oid),
302                             ref->name);
303         }
304         if (!update_seen)
305                 goto free_return;
306
307         if (sign_buffer(&cert, &cert, signing_key))
308                 die(_("failed to sign the push certificate"));
309
310         packet_buf_write(req_buf, "push-cert%c%s", 0, cap_string);
311         for (cp = cert.buf; cp < cert.buf + cert.len; cp = np) {
312                 np = next_line(cp, cert.buf + cert.len - cp);
313                 packet_buf_write(req_buf,
314                                  "%.*s", (int)(np - cp), cp);
315         }
316         packet_buf_write(req_buf, "push-cert-end\n");
317
318 free_return:
319         free(signing_key);
320         strbuf_release(&cert);
321         return update_seen;
322 }
323
324
325 static int atomic_push_failure(struct send_pack_args *args,
326                                struct ref *remote_refs,
327                                struct ref *failing_ref)
328 {
329         struct ref *ref;
330         /* Mark other refs as failed */
331         for (ref = remote_refs; ref; ref = ref->next) {
332                 if (!ref->peer_ref && !args->send_mirror)
333                         continue;
334
335                 switch (ref->status) {
336                 case REF_STATUS_EXPECTING_REPORT:
337                         ref->status = REF_STATUS_ATOMIC_PUSH_FAILED;
338                         continue;
339                 default:
340                         break; /* do nothing */
341                 }
342         }
343         return error("atomic push failed for ref %s. status: %d\n",
344                      failing_ref->name, failing_ref->status);
345 }
346
347 #define NONCE_LEN_LIMIT 256
348
349 static void reject_invalid_nonce(const char *nonce, int len)
350 {
351         int i = 0;
352
353         if (NONCE_LEN_LIMIT <= len)
354                 die("the receiving end asked to sign an invalid nonce <%.*s>",
355                     len, nonce);
356
357         for (i = 0; i < len; i++) {
358                 int ch = nonce[i] & 0xFF;
359                 if (isalnum(ch) ||
360                     ch == '-' || ch == '.' ||
361                     ch == '/' || ch == '+' ||
362                     ch == '=' || ch == '_')
363                         continue;
364                 die("the receiving end asked to sign an invalid nonce <%.*s>",
365                     len, nonce);
366         }
367 }
368
369 int send_pack(struct send_pack_args *args,
370               int fd[], struct child_process *conn,
371               struct ref *remote_refs,
372               struct oid_array *extra_have)
373 {
374         int in = fd[0];
375         int out = fd[1];
376         struct strbuf req_buf = STRBUF_INIT;
377         struct strbuf cap_buf = STRBUF_INIT;
378         struct ref *ref;
379         int need_pack_data = 0;
380         int allow_deleting_refs = 0;
381         int status_report = 0;
382         int use_sideband = 0;
383         int quiet_supported = 0;
384         int agent_supported = 0;
385         int use_atomic = 0;
386         int atomic_supported = 0;
387         int use_push_options = 0;
388         int push_options_supported = 0;
389         unsigned cmds_sent = 0;
390         int ret;
391         struct async demux;
392         const char *push_cert_nonce = NULL;
393
394         /* Does the other end support the reporting? */
395         if (server_supports("report-status"))
396                 status_report = 1;
397         if (server_supports("delete-refs"))
398                 allow_deleting_refs = 1;
399         if (server_supports("ofs-delta"))
400                 args->use_ofs_delta = 1;
401         if (server_supports("side-band-64k"))
402                 use_sideband = 1;
403         if (server_supports("quiet"))
404                 quiet_supported = 1;
405         if (server_supports("agent"))
406                 agent_supported = 1;
407         if (server_supports("no-thin"))
408                 args->use_thin_pack = 0;
409         if (server_supports("atomic"))
410                 atomic_supported = 1;
411         if (server_supports("push-options"))
412                 push_options_supported = 1;
413
414         if (args->push_cert != SEND_PACK_PUSH_CERT_NEVER) {
415                 int len;
416                 push_cert_nonce = server_feature_value("push-cert", &len);
417                 if (push_cert_nonce) {
418                         reject_invalid_nonce(push_cert_nonce, len);
419                         push_cert_nonce = xmemdupz(push_cert_nonce, len);
420                 } else if (args->push_cert == SEND_PACK_PUSH_CERT_ALWAYS) {
421                         die(_("the receiving end does not support --signed push"));
422                 } else if (args->push_cert == SEND_PACK_PUSH_CERT_IF_ASKED) {
423                         warning(_("not sending a push certificate since the"
424                                   " receiving end does not support --signed"
425                                   " push"));
426                 }
427         }
428
429         if (!remote_refs) {
430                 fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
431                         "Perhaps you should specify a branch such as 'master'.\n");
432                 return 0;
433         }
434         if (args->atomic && !atomic_supported)
435                 die(_("the receiving end does not support --atomic push"));
436
437         use_atomic = atomic_supported && args->atomic;
438
439         if (args->push_options && !push_options_supported)
440                 die(_("the receiving end does not support push options"));
441
442         use_push_options = push_options_supported && args->push_options;
443
444         if (status_report)
445                 strbuf_addstr(&cap_buf, " report-status");
446         if (use_sideband)
447                 strbuf_addstr(&cap_buf, " side-band-64k");
448         if (quiet_supported && (args->quiet || !args->progress))
449                 strbuf_addstr(&cap_buf, " quiet");
450         if (use_atomic)
451                 strbuf_addstr(&cap_buf, " atomic");
452         if (use_push_options)
453                 strbuf_addstr(&cap_buf, " push-options");
454         if (agent_supported)
455                 strbuf_addf(&cap_buf, " agent=%s", git_user_agent_sanitized());
456
457         /*
458          * NEEDSWORK: why does delete-refs have to be so specific to
459          * send-pack machinery that set_ref_status_for_push() cannot
460          * set this bit for us???
461          */
462         for (ref = remote_refs; ref; ref = ref->next)
463                 if (ref->deletion && !allow_deleting_refs)
464                         ref->status = REF_STATUS_REJECT_NODELETE;
465
466         if (!args->dry_run)
467                 advertise_shallow_grafts_buf(&req_buf);
468
469         if (!args->dry_run && push_cert_nonce)
470                 cmds_sent = generate_push_cert(&req_buf, remote_refs, args,
471                                                cap_buf.buf, push_cert_nonce);
472
473         /*
474          * Clear the status for each ref and see if we need to send
475          * the pack data.
476          */
477         for (ref = remote_refs; ref; ref = ref->next) {
478                 switch (check_to_send_update(ref, args)) {
479                 case 0: /* no error */
480                         break;
481                 case CHECK_REF_STATUS_REJECTED:
482                         /*
483                          * When we know the server would reject a ref update if
484                          * we were to send it and we're trying to send the refs
485                          * atomically, abort the whole operation.
486                          */
487                         if (use_atomic) {
488                                 strbuf_release(&req_buf);
489                                 strbuf_release(&cap_buf);
490                                 return atomic_push_failure(args, remote_refs, ref);
491                         }
492                         /* else fallthrough */
493                 default:
494                         continue;
495                 }
496                 if (!ref->deletion)
497                         need_pack_data = 1;
498
499                 if (args->dry_run || !status_report)
500                         ref->status = REF_STATUS_OK;
501                 else
502                         ref->status = REF_STATUS_EXPECTING_REPORT;
503         }
504
505         /*
506          * Finally, tell the other end!
507          */
508         for (ref = remote_refs; ref; ref = ref->next) {
509                 char *old_hex, *new_hex;
510
511                 if (args->dry_run || push_cert_nonce)
512                         continue;
513
514                 if (check_to_send_update(ref, args) < 0)
515                         continue;
516
517                 old_hex = oid_to_hex(&ref->old_oid);
518                 new_hex = oid_to_hex(&ref->new_oid);
519                 if (!cmds_sent) {
520                         packet_buf_write(&req_buf,
521                                          "%s %s %s%c%s",
522                                          old_hex, new_hex, ref->name, 0,
523                                          cap_buf.buf);
524                         cmds_sent = 1;
525                 } else {
526                         packet_buf_write(&req_buf, "%s %s %s",
527                                          old_hex, new_hex, ref->name);
528                 }
529         }
530
531         if (use_push_options) {
532                 struct string_list_item *item;
533
534                 packet_buf_flush(&req_buf);
535                 for_each_string_list_item(item, args->push_options)
536                         packet_buf_write(&req_buf, "%s", item->string);
537         }
538
539         if (args->stateless_rpc) {
540                 if (!args->dry_run && (cmds_sent || is_repository_shallow())) {
541                         packet_buf_flush(&req_buf);
542                         send_sideband(out, -1, req_buf.buf, req_buf.len, LARGE_PACKET_MAX);
543                 }
544         } else {
545                 write_or_die(out, req_buf.buf, req_buf.len);
546                 packet_flush(out);
547         }
548         strbuf_release(&req_buf);
549         strbuf_release(&cap_buf);
550
551         if (use_sideband && cmds_sent) {
552                 memset(&demux, 0, sizeof(demux));
553                 demux.proc = sideband_demux;
554                 demux.data = fd;
555                 demux.out = -1;
556                 demux.isolate_sigpipe = 1;
557                 if (start_async(&demux))
558                         die("send-pack: unable to fork off sideband demultiplexer");
559                 in = demux.out;
560         }
561
562         if (need_pack_data && cmds_sent) {
563                 if (pack_objects(out, remote_refs, extra_have, args) < 0) {
564                         for (ref = remote_refs; ref; ref = ref->next)
565                                 ref->status = REF_STATUS_NONE;
566                         if (args->stateless_rpc)
567                                 close(out);
568                         if (git_connection_is_socket(conn))
569                                 shutdown(fd[0], SHUT_WR);
570
571                         /*
572                          * Do not even bother with the return value; we know we
573                          * are failing, and just want the error() side effects.
574                          */
575                         if (status_report)
576                                 receive_unpack_status(in);
577
578                         if (use_sideband) {
579                                 close(demux.out);
580                                 finish_async(&demux);
581                         }
582                         fd[1] = -1;
583                         return -1;
584                 }
585                 if (!args->stateless_rpc)
586                         /* Closed by pack_objects() via start_command() */
587                         fd[1] = -1;
588         }
589         if (args->stateless_rpc && cmds_sent)
590                 packet_flush(out);
591
592         if (status_report && cmds_sent)
593                 ret = receive_status(in, remote_refs);
594         else
595                 ret = 0;
596         if (args->stateless_rpc)
597                 packet_flush(out);
598
599         if (use_sideband && cmds_sent) {
600                 close(demux.out);
601                 if (finish_async(&demux)) {
602                         error("error in sideband demultiplexer");
603                         ret = -1;
604                 }
605         }
606
607         if (ret < 0)
608                 return ret;
609
610         if (args->porcelain)
611                 return 0;
612
613         for (ref = remote_refs; ref; ref = ref->next) {
614                 switch (ref->status) {
615                 case REF_STATUS_NONE:
616                 case REF_STATUS_UPTODATE:
617                 case REF_STATUS_OK:
618                         break;
619                 default:
620                         return -1;
621                 }
622         }
623         return 0;
624 }