Merge branch 'as/read-tree-prefix-doc-fix'
[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 unsigned char *sha1, FILE *fh, int negative)
41 {
42         if (negative && !has_sha1_file(sha1))
43                 return;
44
45         if (negative)
46                 putc('^', fh);
47         fputs(sha1_to_hex(sha1), 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].hash, po_in, 1);
93
94         while (refs) {
95                 if (!is_null_oid(&refs->old_oid))
96                         feed_object(refs->old_oid.hash, po_in, 1);
97                 if (!is_null_oid(&refs->new_oid))
98                         feed_object(refs->new_oid.hash, 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 (!skip_prefix(line, "unpack ", &line))
141                 return error(_("unable to parse remote unpack status: %s"), line);
142         if (strcmp(line, "ok"))
143                 return error(_("remote unpack failed: %s"), line);
144         return 0;
145 }
146
147 static int receive_status(int in, struct ref *refs)
148 {
149         struct ref *hint;
150         int ret;
151
152         hint = NULL;
153         ret = receive_unpack_status(in);
154         while (1) {
155                 char *refname;
156                 char *msg;
157                 char *line = packet_read_line(in, NULL);
158                 if (!line)
159                         break;
160                 if (!starts_with(line, "ok ") && !starts_with(line, "ng ")) {
161                         error("invalid ref status from remote: %s", line);
162                         ret = -1;
163                         break;
164                 }
165
166                 refname = line + 3;
167                 msg = strchr(refname, ' ');
168                 if (msg)
169                         *msg++ = '\0';
170
171                 /* first try searching at our hint, falling back to all refs */
172                 if (hint)
173                         hint = find_ref_by_name(hint, refname);
174                 if (!hint)
175                         hint = find_ref_by_name(refs, refname);
176                 if (!hint) {
177                         warning("remote reported status on unknown ref: %s",
178                                         refname);
179                         continue;
180                 }
181                 if (hint->status != REF_STATUS_EXPECTING_REPORT) {
182                         warning("remote reported status on unexpected ref: %s",
183                                         refname);
184                         continue;
185                 }
186
187                 if (line[0] == 'o' && line[1] == 'k')
188                         hint->status = REF_STATUS_OK;
189                 else {
190                         hint->status = REF_STATUS_REMOTE_REJECT;
191                         ret = -1;
192                 }
193                 hint->remote_status = xstrdup_or_null(msg);
194                 /* start our next search from the next ref */
195                 hint = hint->next;
196         }
197         return ret;
198 }
199
200 static int sideband_demux(int in, int out, void *data)
201 {
202         int *fd = data, ret;
203 #ifdef NO_PTHREADS
204         close(fd[1]);
205 #endif
206         ret = recv_sideband("send-pack", fd[0], out);
207         close(out);
208         return ret;
209 }
210
211 static int advertise_shallow_grafts_cb(const struct commit_graft *graft, void *cb)
212 {
213         struct strbuf *sb = cb;
214         if (graft->nr_parent == -1)
215                 packet_buf_write(sb, "shallow %s\n", oid_to_hex(&graft->oid));
216         return 0;
217 }
218
219 static void advertise_shallow_grafts_buf(struct strbuf *sb)
220 {
221         if (!is_repository_shallow())
222                 return;
223         for_each_commit_graft(advertise_shallow_grafts_cb, sb);
224 }
225
226 #define CHECK_REF_NO_PUSH -1
227 #define CHECK_REF_STATUS_REJECTED -2
228 #define CHECK_REF_UPTODATE -3
229 static int check_to_send_update(const struct ref *ref, const struct send_pack_args *args)
230 {
231         if (!ref->peer_ref && !args->send_mirror)
232                 return CHECK_REF_NO_PUSH;
233
234         /* Check for statuses set by set_ref_status_for_push() */
235         switch (ref->status) {
236         case REF_STATUS_REJECT_NONFASTFORWARD:
237         case REF_STATUS_REJECT_ALREADY_EXISTS:
238         case REF_STATUS_REJECT_FETCH_FIRST:
239         case REF_STATUS_REJECT_NEEDS_FORCE:
240         case REF_STATUS_REJECT_STALE:
241         case REF_STATUS_REJECT_NODELETE:
242                 return CHECK_REF_STATUS_REJECTED;
243         case REF_STATUS_UPTODATE:
244                 return CHECK_REF_UPTODATE;
245         default:
246                 return 0;
247         }
248 }
249
250 /*
251  * the beginning of the next line, or the end of buffer.
252  *
253  * NEEDSWORK: perhaps move this to git-compat-util.h or somewhere and
254  * convert many similar uses found by "git grep -A4 memchr".
255  */
256 static const char *next_line(const char *line, size_t len)
257 {
258         const char *nl = memchr(line, '\n', len);
259         if (!nl)
260                 return line + len; /* incomplete line */
261         return nl + 1;
262 }
263
264 static int generate_push_cert(struct strbuf *req_buf,
265                               const struct ref *remote_refs,
266                               struct send_pack_args *args,
267                               const char *cap_string,
268                               const char *push_cert_nonce)
269 {
270         const struct ref *ref;
271         struct string_list_item *item;
272         char *signing_key = xstrdup(get_signing_key());
273         const char *cp, *np;
274         struct strbuf cert = STRBUF_INIT;
275         int update_seen = 0;
276
277         strbuf_addstr(&cert, "certificate version 0.1\n");
278         strbuf_addf(&cert, "pusher %s ", signing_key);
279         datestamp(&cert);
280         strbuf_addch(&cert, '\n');
281         if (args->url && *args->url) {
282                 char *anon_url = transport_anonymize_url(args->url);
283                 strbuf_addf(&cert, "pushee %s\n", anon_url);
284                 free(anon_url);
285         }
286         if (push_cert_nonce[0])
287                 strbuf_addf(&cert, "nonce %s\n", push_cert_nonce);
288         if (args->push_options)
289                 for_each_string_list_item(item, args->push_options)
290                         strbuf_addf(&cert, "push-option %s\n", item->string);
291         strbuf_addstr(&cert, "\n");
292
293         for (ref = remote_refs; ref; ref = ref->next) {
294                 if (check_to_send_update(ref, args) < 0)
295                         continue;
296                 update_seen = 1;
297                 strbuf_addf(&cert, "%s %s %s\n",
298                             oid_to_hex(&ref->old_oid),
299                             oid_to_hex(&ref->new_oid),
300                             ref->name);
301         }
302         if (!update_seen)
303                 goto free_return;
304
305         if (sign_buffer(&cert, &cert, signing_key))
306                 die(_("failed to sign the push certificate"));
307
308         packet_buf_write(req_buf, "push-cert%c%s", 0, cap_string);
309         for (cp = cert.buf; cp < cert.buf + cert.len; cp = np) {
310                 np = next_line(cp, cert.buf + cert.len - cp);
311                 packet_buf_write(req_buf,
312                                  "%.*s", (int)(np - cp), cp);
313         }
314         packet_buf_write(req_buf, "push-cert-end\n");
315
316 free_return:
317         free(signing_key);
318         strbuf_release(&cert);
319         return update_seen;
320 }
321
322
323 static int atomic_push_failure(struct send_pack_args *args,
324                                struct ref *remote_refs,
325                                struct ref *failing_ref)
326 {
327         struct ref *ref;
328         /* Mark other refs as failed */
329         for (ref = remote_refs; ref; ref = ref->next) {
330                 if (!ref->peer_ref && !args->send_mirror)
331                         continue;
332
333                 switch (ref->status) {
334                 case REF_STATUS_EXPECTING_REPORT:
335                         ref->status = REF_STATUS_ATOMIC_PUSH_FAILED;
336                         continue;
337                 default:
338                         break; /* do nothing */
339                 }
340         }
341         return error("atomic push failed for ref %s. status: %d\n",
342                      failing_ref->name, failing_ref->status);
343 }
344
345 #define NONCE_LEN_LIMIT 256
346
347 static void reject_invalid_nonce(const char *nonce, int len)
348 {
349         int i = 0;
350
351         if (NONCE_LEN_LIMIT <= len)
352                 die("the receiving end asked to sign an invalid nonce <%.*s>",
353                     len, nonce);
354
355         for (i = 0; i < len; i++) {
356                 int ch = nonce[i] & 0xFF;
357                 if (isalnum(ch) ||
358                     ch == '-' || ch == '.' ||
359                     ch == '/' || ch == '+' ||
360                     ch == '=' || ch == '_')
361                         continue;
362                 die("the receiving end asked to sign an invalid nonce <%.*s>",
363                     len, nonce);
364         }
365 }
366
367 int send_pack(struct send_pack_args *args,
368               int fd[], struct child_process *conn,
369               struct ref *remote_refs,
370               struct oid_array *extra_have)
371 {
372         int in = fd[0];
373         int out = fd[1];
374         struct strbuf req_buf = STRBUF_INIT;
375         struct strbuf cap_buf = STRBUF_INIT;
376         struct ref *ref;
377         int need_pack_data = 0;
378         int allow_deleting_refs = 0;
379         int status_report = 0;
380         int use_sideband = 0;
381         int quiet_supported = 0;
382         int agent_supported = 0;
383         int use_atomic = 0;
384         int atomic_supported = 0;
385         int use_push_options = 0;
386         int push_options_supported = 0;
387         unsigned cmds_sent = 0;
388         int ret;
389         struct async demux;
390         const char *push_cert_nonce = NULL;
391
392         /* Does the other end support the reporting? */
393         if (server_supports("report-status"))
394                 status_report = 1;
395         if (server_supports("delete-refs"))
396                 allow_deleting_refs = 1;
397         if (server_supports("ofs-delta"))
398                 args->use_ofs_delta = 1;
399         if (server_supports("side-band-64k"))
400                 use_sideband = 1;
401         if (server_supports("quiet"))
402                 quiet_supported = 1;
403         if (server_supports("agent"))
404                 agent_supported = 1;
405         if (server_supports("no-thin"))
406                 args->use_thin_pack = 0;
407         if (server_supports("atomic"))
408                 atomic_supported = 1;
409         if (server_supports("push-options"))
410                 push_options_supported = 1;
411
412         if (args->push_cert != SEND_PACK_PUSH_CERT_NEVER) {
413                 int len;
414                 push_cert_nonce = server_feature_value("push-cert", &len);
415                 if (push_cert_nonce) {
416                         reject_invalid_nonce(push_cert_nonce, len);
417                         push_cert_nonce = xmemdupz(push_cert_nonce, len);
418                 } else if (args->push_cert == SEND_PACK_PUSH_CERT_ALWAYS) {
419                         die(_("the receiving end does not support --signed push"));
420                 } else if (args->push_cert == SEND_PACK_PUSH_CERT_IF_ASKED) {
421                         warning(_("not sending a push certificate since the"
422                                   " receiving end does not support --signed"
423                                   " push"));
424                 }
425         }
426
427         if (!remote_refs) {
428                 fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
429                         "Perhaps you should specify a branch such as 'master'.\n");
430                 return 0;
431         }
432         if (args->atomic && !atomic_supported)
433                 die(_("the receiving end does not support --atomic push"));
434
435         use_atomic = atomic_supported && args->atomic;
436
437         if (args->push_options && !push_options_supported)
438                 die(_("the receiving end does not support push options"));
439
440         use_push_options = push_options_supported && args->push_options;
441
442         if (status_report)
443                 strbuf_addstr(&cap_buf, " report-status");
444         if (use_sideband)
445                 strbuf_addstr(&cap_buf, " side-band-64k");
446         if (quiet_supported && (args->quiet || !args->progress))
447                 strbuf_addstr(&cap_buf, " quiet");
448         if (use_atomic)
449                 strbuf_addstr(&cap_buf, " atomic");
450         if (use_push_options)
451                 strbuf_addstr(&cap_buf, " push-options");
452         if (agent_supported)
453                 strbuf_addf(&cap_buf, " agent=%s", git_user_agent_sanitized());
454
455         /*
456          * NEEDSWORK: why does delete-refs have to be so specific to
457          * send-pack machinery that set_ref_status_for_push() cannot
458          * set this bit for us???
459          */
460         for (ref = remote_refs; ref; ref = ref->next)
461                 if (ref->deletion && !allow_deleting_refs)
462                         ref->status = REF_STATUS_REJECT_NODELETE;
463
464         if (!args->dry_run)
465                 advertise_shallow_grafts_buf(&req_buf);
466
467         if (!args->dry_run && push_cert_nonce)
468                 cmds_sent = generate_push_cert(&req_buf, remote_refs, args,
469                                                cap_buf.buf, push_cert_nonce);
470
471         /*
472          * Clear the status for each ref and see if we need to send
473          * the pack data.
474          */
475         for (ref = remote_refs; ref; ref = ref->next) {
476                 switch (check_to_send_update(ref, args)) {
477                 case 0: /* no error */
478                         break;
479                 case CHECK_REF_STATUS_REJECTED:
480                         /*
481                          * When we know the server would reject a ref update if
482                          * we were to send it and we're trying to send the refs
483                          * atomically, abort the whole operation.
484                          */
485                         if (use_atomic) {
486                                 strbuf_release(&req_buf);
487                                 strbuf_release(&cap_buf);
488                                 return atomic_push_failure(args, remote_refs, ref);
489                         }
490                         /* else fallthrough */
491                 default:
492                         continue;
493                 }
494                 if (!ref->deletion)
495                         need_pack_data = 1;
496
497                 if (args->dry_run || !status_report)
498                         ref->status = REF_STATUS_OK;
499                 else
500                         ref->status = REF_STATUS_EXPECTING_REPORT;
501         }
502
503         /*
504          * Finally, tell the other end!
505          */
506         for (ref = remote_refs; ref; ref = ref->next) {
507                 char *old_hex, *new_hex;
508
509                 if (args->dry_run || push_cert_nonce)
510                         continue;
511
512                 if (check_to_send_update(ref, args) < 0)
513                         continue;
514
515                 old_hex = oid_to_hex(&ref->old_oid);
516                 new_hex = oid_to_hex(&ref->new_oid);
517                 if (!cmds_sent) {
518                         packet_buf_write(&req_buf,
519                                          "%s %s %s%c%s",
520                                          old_hex, new_hex, ref->name, 0,
521                                          cap_buf.buf);
522                         cmds_sent = 1;
523                 } else {
524                         packet_buf_write(&req_buf, "%s %s %s",
525                                          old_hex, new_hex, ref->name);
526                 }
527         }
528
529         if (use_push_options) {
530                 struct string_list_item *item;
531
532                 packet_buf_flush(&req_buf);
533                 for_each_string_list_item(item, args->push_options)
534                         packet_buf_write(&req_buf, "%s", item->string);
535         }
536
537         if (args->stateless_rpc) {
538                 if (!args->dry_run && (cmds_sent || is_repository_shallow())) {
539                         packet_buf_flush(&req_buf);
540                         send_sideband(out, -1, req_buf.buf, req_buf.len, LARGE_PACKET_MAX);
541                 }
542         } else {
543                 write_or_die(out, req_buf.buf, req_buf.len);
544                 packet_flush(out);
545         }
546         strbuf_release(&req_buf);
547         strbuf_release(&cap_buf);
548
549         if (use_sideband && cmds_sent) {
550                 memset(&demux, 0, sizeof(demux));
551                 demux.proc = sideband_demux;
552                 demux.data = fd;
553                 demux.out = -1;
554                 demux.isolate_sigpipe = 1;
555                 if (start_async(&demux))
556                         die("send-pack: unable to fork off sideband demultiplexer");
557                 in = demux.out;
558         }
559
560         if (need_pack_data && cmds_sent) {
561                 if (pack_objects(out, remote_refs, extra_have, args) < 0) {
562                         for (ref = remote_refs; ref; ref = ref->next)
563                                 ref->status = REF_STATUS_NONE;
564                         if (args->stateless_rpc)
565                                 close(out);
566                         if (git_connection_is_socket(conn))
567                                 shutdown(fd[0], SHUT_WR);
568
569                         /*
570                          * Do not even bother with the return value; we know we
571                          * are failing, and just want the error() side effects.
572                          */
573                         if (status_report)
574                                 receive_unpack_status(in);
575
576                         if (use_sideband) {
577                                 close(demux.out);
578                                 finish_async(&demux);
579                         }
580                         fd[1] = -1;
581                         return -1;
582                 }
583                 if (!args->stateless_rpc)
584                         /* Closed by pack_objects() via start_command() */
585                         fd[1] = -1;
586         }
587         if (args->stateless_rpc && cmds_sent)
588                 packet_flush(out);
589
590         if (status_report && cmds_sent)
591                 ret = receive_status(in, remote_refs);
592         else
593                 ret = 0;
594         if (args->stateless_rpc)
595                 packet_flush(out);
596
597         if (use_sideband && cmds_sent) {
598                 close(demux.out);
599                 if (finish_async(&demux)) {
600                         error("error in sideband demultiplexer");
601                         ret = -1;
602                 }
603         }
604
605         if (ret < 0)
606                 return ret;
607
608         if (args->porcelain)
609                 return 0;
610
611         for (ref = remote_refs; ref; ref = ref->next) {
612                 switch (ref->status) {
613                 case REF_STATUS_NONE:
614                 case REF_STATUS_UPTODATE:
615                 case REF_STATUS_OK:
616                         break;
617                 default:
618                         return -1;
619                 }
620         }
621         return 0;
622 }