Merge branch 'ao/p4-d-f-conflict-recover'
[git] / send-pack.c
1 #include "builtin.h"
2 #include "config.h"
3 #include "commit.h"
4 #include "refs.h"
5 #include "object-store.h"
6 #include "pkt-line.h"
7 #include "sideband.h"
8 #include "run-command.h"
9 #include "remote.h"
10 #include "connect.h"
11 #include "send-pack.h"
12 #include "quote.h"
13 #include "transport.h"
14 #include "version.h"
15 #include "oid-array.h"
16 #include "gpg-interface.h"
17 #include "cache.h"
18 #include "shallow.h"
19
20 int option_parse_push_signed(const struct option *opt,
21                              const char *arg, int unset)
22 {
23         if (unset) {
24                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_NEVER;
25                 return 0;
26         }
27         switch (git_parse_maybe_bool(arg)) {
28         case 1:
29                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_ALWAYS;
30                 return 0;
31         case 0:
32                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_NEVER;
33                 return 0;
34         }
35         if (!strcasecmp("if-asked", arg)) {
36                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_IF_ASKED;
37                 return 0;
38         }
39         die("bad %s argument: %s", opt->long_name, arg);
40 }
41
42 static void feed_object(const struct object_id *oid, FILE *fh, int negative)
43 {
44         if (negative &&
45             !has_object_file_with_flags(oid,
46                                         OBJECT_INFO_SKIP_FETCH_OBJECT |
47                                         OBJECT_INFO_QUICK))
48                 return;
49
50         if (negative)
51                 putc('^', fh);
52         fputs(oid_to_hex(oid), fh);
53         putc('\n', fh);
54 }
55
56 /*
57  * Make a pack stream and spit it out into file descriptor fd
58  */
59 static int pack_objects(int fd, struct ref *refs, struct oid_array *extra, struct send_pack_args *args)
60 {
61         /*
62          * The child becomes pack-objects --revs; we feed
63          * the revision parameters to it via its stdin and
64          * let its stdout go back to the other end.
65          */
66         struct child_process po = CHILD_PROCESS_INIT;
67         FILE *po_in;
68         int i;
69         int rc;
70
71         argv_array_push(&po.args, "pack-objects");
72         argv_array_push(&po.args, "--all-progress-implied");
73         argv_array_push(&po.args, "--revs");
74         argv_array_push(&po.args, "--stdout");
75         if (args->use_thin_pack)
76                 argv_array_push(&po.args, "--thin");
77         if (args->use_ofs_delta)
78                 argv_array_push(&po.args, "--delta-base-offset");
79         if (args->quiet || !args->progress)
80                 argv_array_push(&po.args, "-q");
81         if (args->progress)
82                 argv_array_push(&po.args, "--progress");
83         if (is_repository_shallow(the_repository))
84                 argv_array_push(&po.args, "--shallow");
85         po.in = -1;
86         po.out = args->stateless_rpc ? -1 : fd;
87         po.git_cmd = 1;
88         if (start_command(&po))
89                 die_errno("git pack-objects failed");
90
91         /*
92          * We feed the pack-objects we just spawned with revision
93          * parameters by writing to the pipe.
94          */
95         po_in = xfdopen(po.in, "w");
96         for (i = 0; i < extra->nr; i++)
97                 feed_object(&extra->oid[i], po_in, 1);
98
99         while (refs) {
100                 if (!is_null_oid(&refs->old_oid))
101                         feed_object(&refs->old_oid, po_in, 1);
102                 if (!is_null_oid(&refs->new_oid))
103                         feed_object(&refs->new_oid, po_in, 0);
104                 refs = refs->next;
105         }
106
107         fflush(po_in);
108         if (ferror(po_in))
109                 die_errno("error writing to pack-objects");
110         fclose(po_in);
111
112         if (args->stateless_rpc) {
113                 char *buf = xmalloc(LARGE_PACKET_MAX);
114                 while (1) {
115                         ssize_t n = xread(po.out, buf, LARGE_PACKET_MAX);
116                         if (n <= 0)
117                                 break;
118                         send_sideband(fd, -1, buf, n, LARGE_PACKET_MAX);
119                 }
120                 free(buf);
121                 close(po.out);
122                 po.out = -1;
123         }
124
125         rc = finish_command(&po);
126         if (rc) {
127                 /*
128                  * For a normal non-zero exit, we assume pack-objects wrote
129                  * something useful to stderr. For death by signal, though,
130                  * we should mention it to the user. The exception is SIGPIPE
131                  * (141), because that's a normal occurrence if the remote end
132                  * hangs up (and we'll report that by trying to read the unpack
133                  * status).
134                  */
135                 if (rc > 128 && rc != 141)
136                         error("pack-objects died of signal %d", rc - 128);
137                 return -1;
138         }
139         return 0;
140 }
141
142 static int receive_unpack_status(struct packet_reader *reader)
143 {
144         if (packet_reader_read(reader) != PACKET_READ_NORMAL)
145                 return error(_("unexpected flush packet while reading remote unpack status"));
146         if (!skip_prefix(reader->line, "unpack ", &reader->line))
147                 return error(_("unable to parse remote unpack status: %s"), reader->line);
148         if (strcmp(reader->line, "ok"))
149                 return error(_("remote unpack failed: %s"), reader->line);
150         return 0;
151 }
152
153 static int receive_status(struct packet_reader *reader, struct ref *refs)
154 {
155         struct ref *hint;
156         int ret;
157
158         hint = NULL;
159         ret = receive_unpack_status(reader);
160         while (1) {
161                 const char *refname;
162                 char *msg;
163                 if (packet_reader_read(reader) != PACKET_READ_NORMAL)
164                         break;
165                 if (!starts_with(reader->line, "ok ") && !starts_with(reader->line, "ng ")) {
166                         error("invalid ref status from remote: %s", reader->line);
167                         ret = -1;
168                         break;
169                 }
170
171                 refname = reader->line + 3;
172                 msg = strchr(refname, ' ');
173                 if (msg)
174                         *msg++ = '\0';
175
176                 /* first try searching at our hint, falling back to all refs */
177                 if (hint)
178                         hint = find_ref_by_name(hint, refname);
179                 if (!hint)
180                         hint = find_ref_by_name(refs, refname);
181                 if (!hint) {
182                         warning("remote reported status on unknown ref: %s",
183                                         refname);
184                         continue;
185                 }
186                 if (hint->status != REF_STATUS_EXPECTING_REPORT) {
187                         warning("remote reported status on unexpected ref: %s",
188                                         refname);
189                         continue;
190                 }
191
192                 if (reader->line[0] == 'o' && reader->line[1] == 'k')
193                         hint->status = REF_STATUS_OK;
194                 else
195                         hint->status = REF_STATUS_REMOTE_REJECT;
196                 hint->remote_status = xstrdup_or_null(msg);
197                 /* start our next search from the next ref */
198                 hint = hint->next;
199         }
200         return ret;
201 }
202
203 static int sideband_demux(int in, int out, void *data)
204 {
205         int *fd = data, ret;
206         if (async_with_fork())
207                 close(fd[1]);
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(the_repository))
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 #define NONCE_LEN_LIMIT 256
325
326 static void reject_invalid_nonce(const char *nonce, int len)
327 {
328         int i = 0;
329
330         if (NONCE_LEN_LIMIT <= len)
331                 die("the receiving end asked to sign an invalid nonce <%.*s>",
332                     len, nonce);
333
334         for (i = 0; i < len; i++) {
335                 int ch = nonce[i] & 0xFF;
336                 if (isalnum(ch) ||
337                     ch == '-' || ch == '.' ||
338                     ch == '/' || ch == '+' ||
339                     ch == '=' || ch == '_')
340                         continue;
341                 die("the receiving end asked to sign an invalid nonce <%.*s>",
342                     len, nonce);
343         }
344 }
345
346 int send_pack(struct send_pack_args *args,
347               int fd[], struct child_process *conn,
348               struct ref *remote_refs,
349               struct oid_array *extra_have)
350 {
351         int in = fd[0];
352         int out = fd[1];
353         struct strbuf req_buf = STRBUF_INIT;
354         struct strbuf cap_buf = STRBUF_INIT;
355         struct ref *ref;
356         int need_pack_data = 0;
357         int allow_deleting_refs = 0;
358         int status_report = 0;
359         int use_sideband = 0;
360         int quiet_supported = 0;
361         int agent_supported = 0;
362         int use_atomic = 0;
363         int atomic_supported = 0;
364         int use_push_options = 0;
365         int push_options_supported = 0;
366         unsigned cmds_sent = 0;
367         int ret;
368         struct async demux;
369         const char *push_cert_nonce = NULL;
370         struct packet_reader reader;
371
372         /* Does the other end support the reporting? */
373         if (server_supports("report-status"))
374                 status_report = 1;
375         if (server_supports("delete-refs"))
376                 allow_deleting_refs = 1;
377         if (server_supports("ofs-delta"))
378                 args->use_ofs_delta = 1;
379         if (server_supports("side-band-64k"))
380                 use_sideband = 1;
381         if (server_supports("quiet"))
382                 quiet_supported = 1;
383         if (server_supports("agent"))
384                 agent_supported = 1;
385         if (server_supports("no-thin"))
386                 args->use_thin_pack = 0;
387         if (server_supports("atomic"))
388                 atomic_supported = 1;
389         if (server_supports("push-options"))
390                 push_options_supported = 1;
391
392         if (args->push_cert != SEND_PACK_PUSH_CERT_NEVER) {
393                 int len;
394                 push_cert_nonce = server_feature_value("push-cert", &len);
395                 if (push_cert_nonce) {
396                         reject_invalid_nonce(push_cert_nonce, len);
397                         push_cert_nonce = xmemdupz(push_cert_nonce, len);
398                 } else if (args->push_cert == SEND_PACK_PUSH_CERT_ALWAYS) {
399                         die(_("the receiving end does not support --signed push"));
400                 } else if (args->push_cert == SEND_PACK_PUSH_CERT_IF_ASKED) {
401                         warning(_("not sending a push certificate since the"
402                                   " receiving end does not support --signed"
403                                   " push"));
404                 }
405         }
406
407         if (!remote_refs) {
408                 fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
409                         "Perhaps you should specify a branch such as 'master'.\n");
410                 return 0;
411         }
412         if (args->atomic && !atomic_supported)
413                 die(_("the receiving end does not support --atomic push"));
414
415         use_atomic = atomic_supported && args->atomic;
416
417         if (args->push_options && !push_options_supported)
418                 die(_("the receiving end does not support push options"));
419
420         use_push_options = push_options_supported && args->push_options;
421
422         if (status_report)
423                 strbuf_addstr(&cap_buf, " report-status");
424         if (use_sideband)
425                 strbuf_addstr(&cap_buf, " side-band-64k");
426         if (quiet_supported && (args->quiet || !args->progress))
427                 strbuf_addstr(&cap_buf, " quiet");
428         if (use_atomic)
429                 strbuf_addstr(&cap_buf, " atomic");
430         if (use_push_options)
431                 strbuf_addstr(&cap_buf, " push-options");
432         if (agent_supported)
433                 strbuf_addf(&cap_buf, " agent=%s", git_user_agent_sanitized());
434
435         /*
436          * NEEDSWORK: why does delete-refs have to be so specific to
437          * send-pack machinery that set_ref_status_for_push() cannot
438          * set this bit for us???
439          */
440         for (ref = remote_refs; ref; ref = ref->next)
441                 if (ref->deletion && !allow_deleting_refs)
442                         ref->status = REF_STATUS_REJECT_NODELETE;
443
444         if (!args->dry_run)
445                 advertise_shallow_grafts_buf(&req_buf);
446
447         if (!args->dry_run && push_cert_nonce)
448                 cmds_sent = generate_push_cert(&req_buf, remote_refs, args,
449                                                cap_buf.buf, push_cert_nonce);
450
451         /*
452          * Clear the status for each ref and see if we need to send
453          * the pack data.
454          */
455         for (ref = remote_refs; ref; ref = ref->next) {
456                 switch (check_to_send_update(ref, args)) {
457                 case 0: /* no error */
458                         break;
459                 case CHECK_REF_STATUS_REJECTED:
460                         /*
461                          * When we know the server would reject a ref update if
462                          * we were to send it and we're trying to send the refs
463                          * atomically, abort the whole operation.
464                          */
465                         if (use_atomic) {
466                                 strbuf_release(&req_buf);
467                                 strbuf_release(&cap_buf);
468                                 reject_atomic_push(remote_refs, args->send_mirror);
469                                 error("atomic push failed for ref %s. status: %d\n",
470                                       ref->name, ref->status);
471                                 return args->porcelain ? 0 : -1;
472                         }
473                         /* else fallthrough */
474                 default:
475                         continue;
476                 }
477                 if (!ref->deletion)
478                         need_pack_data = 1;
479
480                 if (args->dry_run || !status_report)
481                         ref->status = REF_STATUS_OK;
482                 else
483                         ref->status = REF_STATUS_EXPECTING_REPORT;
484         }
485
486         /*
487          * Finally, tell the other end!
488          */
489         for (ref = remote_refs; ref; ref = ref->next) {
490                 char *old_hex, *new_hex;
491
492                 if (args->dry_run || push_cert_nonce)
493                         continue;
494
495                 if (check_to_send_update(ref, args) < 0)
496                         continue;
497
498                 old_hex = oid_to_hex(&ref->old_oid);
499                 new_hex = oid_to_hex(&ref->new_oid);
500                 if (!cmds_sent) {
501                         packet_buf_write(&req_buf,
502                                          "%s %s %s%c%s",
503                                          old_hex, new_hex, ref->name, 0,
504                                          cap_buf.buf);
505                         cmds_sent = 1;
506                 } else {
507                         packet_buf_write(&req_buf, "%s %s %s",
508                                          old_hex, new_hex, ref->name);
509                 }
510         }
511
512         if (use_push_options) {
513                 struct string_list_item *item;
514
515                 packet_buf_flush(&req_buf);
516                 for_each_string_list_item(item, args->push_options)
517                         packet_buf_write(&req_buf, "%s", item->string);
518         }
519
520         if (args->stateless_rpc) {
521                 if (!args->dry_run && (cmds_sent || is_repository_shallow(the_repository))) {
522                         packet_buf_flush(&req_buf);
523                         send_sideband(out, -1, req_buf.buf, req_buf.len, LARGE_PACKET_MAX);
524                 }
525         } else {
526                 write_or_die(out, req_buf.buf, req_buf.len);
527                 packet_flush(out);
528         }
529         strbuf_release(&req_buf);
530         strbuf_release(&cap_buf);
531
532         if (use_sideband && cmds_sent) {
533                 memset(&demux, 0, sizeof(demux));
534                 demux.proc = sideband_demux;
535                 demux.data = fd;
536                 demux.out = -1;
537                 demux.isolate_sigpipe = 1;
538                 if (start_async(&demux))
539                         die("send-pack: unable to fork off sideband demultiplexer");
540                 in = demux.out;
541         }
542
543         packet_reader_init(&reader, in, NULL, 0,
544                            PACKET_READ_CHOMP_NEWLINE |
545                            PACKET_READ_DIE_ON_ERR_PACKET);
546
547         if (need_pack_data && cmds_sent) {
548                 if (pack_objects(out, remote_refs, extra_have, args) < 0) {
549                         if (args->stateless_rpc)
550                                 close(out);
551                         if (git_connection_is_socket(conn))
552                                 shutdown(fd[0], SHUT_WR);
553
554                         /*
555                          * Do not even bother with the return value; we know we
556                          * are failing, and just want the error() side effects,
557                          * as well as marking refs with their remote status (if
558                          * we get one).
559                          */
560                         if (status_report)
561                                 receive_status(&reader, remote_refs);
562
563                         if (use_sideband) {
564                                 close(demux.out);
565                                 finish_async(&demux);
566                         }
567                         fd[1] = -1;
568                         return -1;
569                 }
570                 if (!args->stateless_rpc)
571                         /* Closed by pack_objects() via start_command() */
572                         fd[1] = -1;
573         }
574         if (args->stateless_rpc && cmds_sent)
575                 packet_flush(out);
576
577         if (status_report && cmds_sent)
578                 ret = receive_status(&reader, remote_refs);
579         else
580                 ret = 0;
581         if (args->stateless_rpc)
582                 packet_flush(out);
583
584         if (use_sideband && cmds_sent) {
585                 close(demux.out);
586                 if (finish_async(&demux)) {
587                         error("error in sideband demultiplexer");
588                         ret = -1;
589                 }
590         }
591
592         if (ret < 0)
593                 return ret;
594
595         if (args->porcelain)
596                 return 0;
597
598         for (ref = remote_refs; ref; ref = ref->next) {
599                 switch (ref->status) {
600                 case REF_STATUS_NONE:
601                 case REF_STATUS_UPTODATE:
602                 case REF_STATUS_OK:
603                         break;
604                 default:
605                         return -1;
606                 }
607         }
608         return 0;
609 }