unpack-trees: add a note about path invalidation
[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 "sha1-array.h"
16 #include "gpg-interface.h"
17 #include "cache.h"
18
19 int option_parse_push_signed(const struct option *opt,
20                              const char *arg, int unset)
21 {
22         if (unset) {
23                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_NEVER;
24                 return 0;
25         }
26         switch (git_parse_maybe_bool(arg)) {
27         case 1:
28                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_ALWAYS;
29                 return 0;
30         case 0:
31                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_NEVER;
32                 return 0;
33         }
34         if (!strcasecmp("if-asked", arg)) {
35                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_IF_ASKED;
36                 return 0;
37         }
38         die("bad %s argument: %s", opt->long_name, arg);
39 }
40
41 static void feed_object(const struct object_id *oid, FILE *fh, int negative)
42 {
43         if (negative && !has_sha1_file(oid->hash))
44                 return;
45
46         if (negative)
47                 putc('^', fh);
48         fputs(oid_to_hex(oid), fh);
49         putc('\n', fh);
50 }
51
52 /*
53  * Make a pack stream and spit it out into file descriptor fd
54  */
55 static int pack_objects(int fd, struct ref *refs, struct oid_array *extra, struct send_pack_args *args)
56 {
57         /*
58          * The child becomes pack-objects --revs; we feed
59          * the revision parameters to it via its stdin and
60          * let its stdout go back to the other end.
61          */
62         struct child_process po = CHILD_PROCESS_INIT;
63         FILE *po_in;
64         int i;
65         int rc;
66
67         argv_array_push(&po.args, "pack-objects");
68         argv_array_push(&po.args, "--all-progress-implied");
69         argv_array_push(&po.args, "--revs");
70         argv_array_push(&po.args, "--stdout");
71         if (args->use_thin_pack)
72                 argv_array_push(&po.args, "--thin");
73         if (args->use_ofs_delta)
74                 argv_array_push(&po.args, "--delta-base-offset");
75         if (args->quiet || !args->progress)
76                 argv_array_push(&po.args, "-q");
77         if (args->progress)
78                 argv_array_push(&po.args, "--progress");
79         if (is_repository_shallow(the_repository))
80                 argv_array_push(&po.args, "--shallow");
81         po.in = -1;
82         po.out = args->stateless_rpc ? -1 : fd;
83         po.git_cmd = 1;
84         if (start_command(&po))
85                 die_errno("git pack-objects failed");
86
87         /*
88          * We feed the pack-objects we just spawned with revision
89          * parameters by writing to the pipe.
90          */
91         po_in = xfdopen(po.in, "w");
92         for (i = 0; i < extra->nr; i++)
93                 feed_object(&extra->oid[i], po_in, 1);
94
95         while (refs) {
96                 if (!is_null_oid(&refs->old_oid))
97                         feed_object(&refs->old_oid, po_in, 1);
98                 if (!is_null_oid(&refs->new_oid))
99                         feed_object(&refs->new_oid, po_in, 0);
100                 refs = refs->next;
101         }
102
103         fflush(po_in);
104         if (ferror(po_in))
105                 die_errno("error writing to pack-objects");
106         fclose(po_in);
107
108         if (args->stateless_rpc) {
109                 char *buf = xmalloc(LARGE_PACKET_MAX);
110                 while (1) {
111                         ssize_t n = xread(po.out, buf, LARGE_PACKET_MAX);
112                         if (n <= 0)
113                                 break;
114                         send_sideband(fd, -1, buf, n, LARGE_PACKET_MAX);
115                 }
116                 free(buf);
117                 close(po.out);
118                 po.out = -1;
119         }
120
121         rc = finish_command(&po);
122         if (rc) {
123                 /*
124                  * For a normal non-zero exit, we assume pack-objects wrote
125                  * something useful to stderr. For death by signal, though,
126                  * we should mention it to the user. The exception is SIGPIPE
127                  * (141), because that's a normal occurrence if the remote end
128                  * hangs up (and we'll report that by trying to read the unpack
129                  * status).
130                  */
131                 if (rc > 128 && rc != 141)
132                         error("pack-objects died of signal %d", rc - 128);
133                 return -1;
134         }
135         return 0;
136 }
137
138 static int receive_unpack_status(int in)
139 {
140         const char *line = packet_read_line(in, NULL);
141         if (!line)
142                 return error(_("unexpected flush packet while reading remote unpack status"));
143         if (!skip_prefix(line, "unpack ", &line))
144                 return error(_("unable to parse remote unpack status: %s"), line);
145         if (strcmp(line, "ok"))
146                 return error(_("remote unpack failed: %s"), line);
147         return 0;
148 }
149
150 static int receive_status(int in, struct ref *refs)
151 {
152         struct ref *hint;
153         int ret;
154
155         hint = NULL;
156         ret = receive_unpack_status(in);
157         while (1) {
158                 char *refname;
159                 char *msg;
160                 char *line = packet_read_line(in, NULL);
161                 if (!line)
162                         break;
163                 if (!starts_with(line, "ok ") && !starts_with(line, "ng ")) {
164                         error("invalid ref status from remote: %s", line);
165                         ret = -1;
166                         break;
167                 }
168
169                 refname = line + 3;
170                 msg = strchr(refname, ' ');
171                 if (msg)
172                         *msg++ = '\0';
173
174                 /* first try searching at our hint, falling back to all refs */
175                 if (hint)
176                         hint = find_ref_by_name(hint, refname);
177                 if (!hint)
178                         hint = find_ref_by_name(refs, refname);
179                 if (!hint) {
180                         warning("remote reported status on unknown ref: %s",
181                                         refname);
182                         continue;
183                 }
184                 if (hint->status != REF_STATUS_EXPECTING_REPORT) {
185                         warning("remote reported status on unexpected ref: %s",
186                                         refname);
187                         continue;
188                 }
189
190                 if (line[0] == 'o' && line[1] == 'k')
191                         hint->status = REF_STATUS_OK;
192                 else {
193                         hint->status = REF_STATUS_REMOTE_REJECT;
194                         ret = -1;
195                 }
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 #ifdef NO_PTHREADS
207         close(fd[1]);
208 #endif
209         ret = recv_sideband("send-pack", fd[0], out);
210         close(out);
211         return ret;
212 }
213
214 static int advertise_shallow_grafts_cb(const struct commit_graft *graft, void *cb)
215 {
216         struct strbuf *sb = cb;
217         if (graft->nr_parent == -1)
218                 packet_buf_write(sb, "shallow %s\n", oid_to_hex(&graft->oid));
219         return 0;
220 }
221
222 static void advertise_shallow_grafts_buf(struct strbuf *sb)
223 {
224         if (!is_repository_shallow(the_repository))
225                 return;
226         for_each_commit_graft(advertise_shallow_grafts_cb, sb);
227 }
228
229 #define CHECK_REF_NO_PUSH -1
230 #define CHECK_REF_STATUS_REJECTED -2
231 #define CHECK_REF_UPTODATE -3
232 static int check_to_send_update(const struct ref *ref, const struct send_pack_args *args)
233 {
234         if (!ref->peer_ref && !args->send_mirror)
235                 return CHECK_REF_NO_PUSH;
236
237         /* Check for statuses set by set_ref_status_for_push() */
238         switch (ref->status) {
239         case REF_STATUS_REJECT_NONFASTFORWARD:
240         case REF_STATUS_REJECT_ALREADY_EXISTS:
241         case REF_STATUS_REJECT_FETCH_FIRST:
242         case REF_STATUS_REJECT_NEEDS_FORCE:
243         case REF_STATUS_REJECT_STALE:
244         case REF_STATUS_REJECT_NODELETE:
245                 return CHECK_REF_STATUS_REJECTED;
246         case REF_STATUS_UPTODATE:
247                 return CHECK_REF_UPTODATE;
248         default:
249                 return 0;
250         }
251 }
252
253 /*
254  * the beginning of the next line, or the end of buffer.
255  *
256  * NEEDSWORK: perhaps move this to git-compat-util.h or somewhere and
257  * convert many similar uses found by "git grep -A4 memchr".
258  */
259 static const char *next_line(const char *line, size_t len)
260 {
261         const char *nl = memchr(line, '\n', len);
262         if (!nl)
263                 return line + len; /* incomplete line */
264         return nl + 1;
265 }
266
267 static int generate_push_cert(struct strbuf *req_buf,
268                               const struct ref *remote_refs,
269                               struct send_pack_args *args,
270                               const char *cap_string,
271                               const char *push_cert_nonce)
272 {
273         const struct ref *ref;
274         struct string_list_item *item;
275         char *signing_key = xstrdup(get_signing_key());
276         const char *cp, *np;
277         struct strbuf cert = STRBUF_INIT;
278         int update_seen = 0;
279
280         strbuf_addstr(&cert, "certificate version 0.1\n");
281         strbuf_addf(&cert, "pusher %s ", signing_key);
282         datestamp(&cert);
283         strbuf_addch(&cert, '\n');
284         if (args->url && *args->url) {
285                 char *anon_url = transport_anonymize_url(args->url);
286                 strbuf_addf(&cert, "pushee %s\n", anon_url);
287                 free(anon_url);
288         }
289         if (push_cert_nonce[0])
290                 strbuf_addf(&cert, "nonce %s\n", push_cert_nonce);
291         if (args->push_options)
292                 for_each_string_list_item(item, args->push_options)
293                         strbuf_addf(&cert, "push-option %s\n", item->string);
294         strbuf_addstr(&cert, "\n");
295
296         for (ref = remote_refs; ref; ref = ref->next) {
297                 if (check_to_send_update(ref, args) < 0)
298                         continue;
299                 update_seen = 1;
300                 strbuf_addf(&cert, "%s %s %s\n",
301                             oid_to_hex(&ref->old_oid),
302                             oid_to_hex(&ref->new_oid),
303                             ref->name);
304         }
305         if (!update_seen)
306                 goto free_return;
307
308         if (sign_buffer(&cert, &cert, signing_key))
309                 die(_("failed to sign the push certificate"));
310
311         packet_buf_write(req_buf, "push-cert%c%s", 0, cap_string);
312         for (cp = cert.buf; cp < cert.buf + cert.len; cp = np) {
313                 np = next_line(cp, cert.buf + cert.len - cp);
314                 packet_buf_write(req_buf,
315                                  "%.*s", (int)(np - cp), cp);
316         }
317         packet_buf_write(req_buf, "push-cert-end\n");
318
319 free_return:
320         free(signing_key);
321         strbuf_release(&cert);
322         return update_seen;
323 }
324
325
326 static int atomic_push_failure(struct send_pack_args *args,
327                                struct ref *remote_refs,
328                                struct ref *failing_ref)
329 {
330         struct ref *ref;
331         /* Mark other refs as failed */
332         for (ref = remote_refs; ref; ref = ref->next) {
333                 if (!ref->peer_ref && !args->send_mirror)
334                         continue;
335
336                 switch (ref->status) {
337                 case REF_STATUS_EXPECTING_REPORT:
338                         ref->status = REF_STATUS_ATOMIC_PUSH_FAILED;
339                         continue;
340                 default:
341                         break; /* do nothing */
342                 }
343         }
344         return error("atomic push failed for ref %s. status: %d\n",
345                      failing_ref->name, failing_ref->status);
346 }
347
348 #define NONCE_LEN_LIMIT 256
349
350 static void reject_invalid_nonce(const char *nonce, int len)
351 {
352         int i = 0;
353
354         if (NONCE_LEN_LIMIT <= len)
355                 die("the receiving end asked to sign an invalid nonce <%.*s>",
356                     len, nonce);
357
358         for (i = 0; i < len; i++) {
359                 int ch = nonce[i] & 0xFF;
360                 if (isalnum(ch) ||
361                     ch == '-' || ch == '.' ||
362                     ch == '/' || ch == '+' ||
363                     ch == '=' || ch == '_')
364                         continue;
365                 die("the receiving end asked to sign an invalid nonce <%.*s>",
366                     len, nonce);
367         }
368 }
369
370 int send_pack(struct send_pack_args *args,
371               int fd[], struct child_process *conn,
372               struct ref *remote_refs,
373               struct oid_array *extra_have)
374 {
375         int in = fd[0];
376         int out = fd[1];
377         struct strbuf req_buf = STRBUF_INIT;
378         struct strbuf cap_buf = STRBUF_INIT;
379         struct ref *ref;
380         int need_pack_data = 0;
381         int allow_deleting_refs = 0;
382         int status_report = 0;
383         int use_sideband = 0;
384         int quiet_supported = 0;
385         int agent_supported = 0;
386         int use_atomic = 0;
387         int atomic_supported = 0;
388         int use_push_options = 0;
389         int push_options_supported = 0;
390         unsigned cmds_sent = 0;
391         int ret;
392         struct async demux;
393         const char *push_cert_nonce = NULL;
394
395         /* Does the other end support the reporting? */
396         if (server_supports("report-status"))
397                 status_report = 1;
398         if (server_supports("delete-refs"))
399                 allow_deleting_refs = 1;
400         if (server_supports("ofs-delta"))
401                 args->use_ofs_delta = 1;
402         if (server_supports("side-band-64k"))
403                 use_sideband = 1;
404         if (server_supports("quiet"))
405                 quiet_supported = 1;
406         if (server_supports("agent"))
407                 agent_supported = 1;
408         if (server_supports("no-thin"))
409                 args->use_thin_pack = 0;
410         if (server_supports("atomic"))
411                 atomic_supported = 1;
412         if (server_supports("push-options"))
413                 push_options_supported = 1;
414
415         if (args->push_cert != SEND_PACK_PUSH_CERT_NEVER) {
416                 int len;
417                 push_cert_nonce = server_feature_value("push-cert", &len);
418                 if (push_cert_nonce) {
419                         reject_invalid_nonce(push_cert_nonce, len);
420                         push_cert_nonce = xmemdupz(push_cert_nonce, len);
421                 } else if (args->push_cert == SEND_PACK_PUSH_CERT_ALWAYS) {
422                         die(_("the receiving end does not support --signed push"));
423                 } else if (args->push_cert == SEND_PACK_PUSH_CERT_IF_ASKED) {
424                         warning(_("not sending a push certificate since the"
425                                   " receiving end does not support --signed"
426                                   " push"));
427                 }
428         }
429
430         if (!remote_refs) {
431                 fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
432                         "Perhaps you should specify a branch such as 'master'.\n");
433                 return 0;
434         }
435         if (args->atomic && !atomic_supported)
436                 die(_("the receiving end does not support --atomic push"));
437
438         use_atomic = atomic_supported && args->atomic;
439
440         if (args->push_options && !push_options_supported)
441                 die(_("the receiving end does not support push options"));
442
443         use_push_options = push_options_supported && args->push_options;
444
445         if (status_report)
446                 strbuf_addstr(&cap_buf, " report-status");
447         if (use_sideband)
448                 strbuf_addstr(&cap_buf, " side-band-64k");
449         if (quiet_supported && (args->quiet || !args->progress))
450                 strbuf_addstr(&cap_buf, " quiet");
451         if (use_atomic)
452                 strbuf_addstr(&cap_buf, " atomic");
453         if (use_push_options)
454                 strbuf_addstr(&cap_buf, " push-options");
455         if (agent_supported)
456                 strbuf_addf(&cap_buf, " agent=%s", git_user_agent_sanitized());
457
458         /*
459          * NEEDSWORK: why does delete-refs have to be so specific to
460          * send-pack machinery that set_ref_status_for_push() cannot
461          * set this bit for us???
462          */
463         for (ref = remote_refs; ref; ref = ref->next)
464                 if (ref->deletion && !allow_deleting_refs)
465                         ref->status = REF_STATUS_REJECT_NODELETE;
466
467         if (!args->dry_run)
468                 advertise_shallow_grafts_buf(&req_buf);
469
470         if (!args->dry_run && push_cert_nonce)
471                 cmds_sent = generate_push_cert(&req_buf, remote_refs, args,
472                                                cap_buf.buf, push_cert_nonce);
473
474         /*
475          * Clear the status for each ref and see if we need to send
476          * the pack data.
477          */
478         for (ref = remote_refs; ref; ref = ref->next) {
479                 switch (check_to_send_update(ref, args)) {
480                 case 0: /* no error */
481                         break;
482                 case CHECK_REF_STATUS_REJECTED:
483                         /*
484                          * When we know the server would reject a ref update if
485                          * we were to send it and we're trying to send the refs
486                          * atomically, abort the whole operation.
487                          */
488                         if (use_atomic) {
489                                 strbuf_release(&req_buf);
490                                 strbuf_release(&cap_buf);
491                                 return atomic_push_failure(args, remote_refs, ref);
492                         }
493                         /* else fallthrough */
494                 default:
495                         continue;
496                 }
497                 if (!ref->deletion)
498                         need_pack_data = 1;
499
500                 if (args->dry_run || !status_report)
501                         ref->status = REF_STATUS_OK;
502                 else
503                         ref->status = REF_STATUS_EXPECTING_REPORT;
504         }
505
506         /*
507          * Finally, tell the other end!
508          */
509         for (ref = remote_refs; ref; ref = ref->next) {
510                 char *old_hex, *new_hex;
511
512                 if (args->dry_run || push_cert_nonce)
513                         continue;
514
515                 if (check_to_send_update(ref, args) < 0)
516                         continue;
517
518                 old_hex = oid_to_hex(&ref->old_oid);
519                 new_hex = oid_to_hex(&ref->new_oid);
520                 if (!cmds_sent) {
521                         packet_buf_write(&req_buf,
522                                          "%s %s %s%c%s",
523                                          old_hex, new_hex, ref->name, 0,
524                                          cap_buf.buf);
525                         cmds_sent = 1;
526                 } else {
527                         packet_buf_write(&req_buf, "%s %s %s",
528                                          old_hex, new_hex, ref->name);
529                 }
530         }
531
532         if (use_push_options) {
533                 struct string_list_item *item;
534
535                 packet_buf_flush(&req_buf);
536                 for_each_string_list_item(item, args->push_options)
537                         packet_buf_write(&req_buf, "%s", item->string);
538         }
539
540         if (args->stateless_rpc) {
541                 if (!args->dry_run && (cmds_sent || is_repository_shallow(the_repository))) {
542                         packet_buf_flush(&req_buf);
543                         send_sideband(out, -1, req_buf.buf, req_buf.len, LARGE_PACKET_MAX);
544                 }
545         } else {
546                 write_or_die(out, req_buf.buf, req_buf.len);
547                 packet_flush(out);
548         }
549         strbuf_release(&req_buf);
550         strbuf_release(&cap_buf);
551
552         if (use_sideband && cmds_sent) {
553                 memset(&demux, 0, sizeof(demux));
554                 demux.proc = sideband_demux;
555                 demux.data = fd;
556                 demux.out = -1;
557                 demux.isolate_sigpipe = 1;
558                 if (start_async(&demux))
559                         die("send-pack: unable to fork off sideband demultiplexer");
560                 in = demux.out;
561         }
562
563         if (need_pack_data && cmds_sent) {
564                 if (pack_objects(out, remote_refs, extra_have, args) < 0) {
565                         for (ref = remote_refs; ref; ref = ref->next)
566                                 ref->status = REF_STATUS_NONE;
567                         if (args->stateless_rpc)
568                                 close(out);
569                         if (git_connection_is_socket(conn))
570                                 shutdown(fd[0], SHUT_WR);
571
572                         /*
573                          * Do not even bother with the return value; we know we
574                          * are failing, and just want the error() side effects.
575                          */
576                         if (status_report)
577                                 receive_unpack_status(in);
578
579                         if (use_sideband) {
580                                 close(demux.out);
581                                 finish_async(&demux);
582                         }
583                         fd[1] = -1;
584                         return -1;
585                 }
586                 if (!args->stateless_rpc)
587                         /* Closed by pack_objects() via start_command() */
588                         fd[1] = -1;
589         }
590         if (args->stateless_rpc && cmds_sent)
591                 packet_flush(out);
592
593         if (status_report && cmds_sent)
594                 ret = receive_status(in, remote_refs);
595         else
596                 ret = 0;
597         if (args->stateless_rpc)
598                 packet_flush(out);
599
600         if (use_sideband && cmds_sent) {
601                 close(demux.out);
602                 if (finish_async(&demux)) {
603                         error("error in sideband demultiplexer");
604                         ret = -1;
605                 }
606         }
607
608         if (ret < 0)
609                 return ret;
610
611         if (args->porcelain)
612                 return 0;
613
614         for (ref = remote_refs; ref; ref = ref->next) {
615                 switch (ref->status) {
616                 case REF_STATUS_NONE:
617                 case REF_STATUS_UPTODATE:
618                 case REF_STATUS_OK:
619                         break;
620                 default:
621                         return -1;
622                 }
623         }
624         return 0;
625 }