Add new `git update` tool
[git] / send-pack.c
1 #include "builtin.h"
2 #include "commit.h"
3 #include "refs.h"
4 #include "pkt-line.h"
5 #include "sideband.h"
6 #include "run-command.h"
7 #include "remote.h"
8 #include "connect.h"
9 #include "send-pack.h"
10 #include "quote.h"
11 #include "transport.h"
12 #include "version.h"
13 #include "sha1-array.h"
14 #include "gpg-interface.h"
15 #include "cache.h"
16
17 int option_parse_push_signed(const struct option *opt,
18                              const char *arg, int unset)
19 {
20         if (unset) {
21                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_NEVER;
22                 return 0;
23         }
24         switch (git_parse_maybe_bool(arg)) {
25         case 1:
26                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_ALWAYS;
27                 return 0;
28         case 0:
29                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_NEVER;
30                 return 0;
31         }
32         if (!strcasecmp("if-asked", arg)) {
33                 *(int *)(opt->value) = SEND_PACK_PUSH_CERT_IF_ASKED;
34                 return 0;
35         }
36         die("bad %s argument: %s", opt->long_name, arg);
37 }
38
39 static int feed_object(const unsigned char *sha1, int fd, int negative)
40 {
41         char buf[42];
42
43         if (negative && !has_sha1_file(sha1))
44                 return 1;
45
46         memcpy(buf + negative, sha1_to_hex(sha1), 40);
47         if (negative)
48                 buf[0] = '^';
49         buf[40 + negative] = '\n';
50         return write_or_whine(fd, buf, 41 + negative, "send-pack: send refs");
51 }
52
53 /*
54  * Make a pack stream and spit it out into file descriptor fd
55  */
56 static int pack_objects(int fd, struct ref *refs, struct sha1_array *extra, struct send_pack_args *args)
57 {
58         /*
59          * The child becomes pack-objects --revs; we feed
60          * the revision parameters to it via its stdin and
61          * let its stdout go back to the other end.
62          */
63         const char *argv[] = {
64                 "pack-objects",
65                 "--all-progress-implied",
66                 "--revs",
67                 "--stdout",
68                 NULL,
69                 NULL,
70                 NULL,
71                 NULL,
72                 NULL,
73                 NULL,
74         };
75         struct child_process po = CHILD_PROCESS_INIT;
76         int i;
77
78         i = 4;
79         if (args->use_thin_pack)
80                 argv[i++] = "--thin";
81         if (args->use_ofs_delta)
82                 argv[i++] = "--delta-base-offset";
83         if (args->quiet || !args->progress)
84                 argv[i++] = "-q";
85         if (args->progress)
86                 argv[i++] = "--progress";
87         if (is_repository_shallow())
88                 argv[i++] = "--shallow";
89         po.argv = argv;
90         po.in = -1;
91         po.out = args->stateless_rpc ? -1 : fd;
92         po.git_cmd = 1;
93         if (start_command(&po))
94                 die_errno("git pack-objects failed");
95
96         /*
97          * We feed the pack-objects we just spawned with revision
98          * parameters by writing to the pipe.
99          */
100         for (i = 0; i < extra->nr; i++)
101                 if (!feed_object(extra->sha1[i], po.in, 1))
102                         break;
103
104         while (refs) {
105                 if (!is_null_oid(&refs->old_oid) &&
106                     !feed_object(refs->old_oid.hash, po.in, 1))
107                         break;
108                 if (!is_null_oid(&refs->new_oid) &&
109                     !feed_object(refs->new_oid.hash, po.in, 0))
110                         break;
111                 refs = refs->next;
112         }
113
114         close(po.in);
115
116         if (args->stateless_rpc) {
117                 char *buf = xmalloc(LARGE_PACKET_MAX);
118                 while (1) {
119                         ssize_t n = xread(po.out, buf, LARGE_PACKET_MAX);
120                         if (n <= 0)
121                                 break;
122                         send_sideband(fd, -1, buf, n, LARGE_PACKET_MAX);
123                 }
124                 free(buf);
125                 close(po.out);
126                 po.out = -1;
127         }
128
129         if (finish_command(&po))
130                 return -1;
131         return 0;
132 }
133
134 static int receive_status(int in, struct ref *refs)
135 {
136         struct ref *hint;
137         int ret = 0;
138         char *line = packet_read_line(in, NULL);
139         if (!starts_with(line, "unpack "))
140                 return error("did not receive remote status");
141         if (strcmp(line, "unpack ok")) {
142                 error("unpack failed: %s", line + 7);
143                 ret = -1;
144         }
145         hint = NULL;
146         while (1) {
147                 char *refname;
148                 char *msg;
149                 line = packet_read_line(in, NULL);
150                 if (!line)
151                         break;
152                 if (!starts_with(line, "ok ") && !starts_with(line, "ng ")) {
153                         error("invalid ref status from remote: %s", line);
154                         ret = -1;
155                         break;
156                 }
157
158                 refname = line + 3;
159                 msg = strchr(refname, ' ');
160                 if (msg)
161                         *msg++ = '\0';
162
163                 /* first try searching at our hint, falling back to all refs */
164                 if (hint)
165                         hint = find_ref_by_name(hint, refname);
166                 if (!hint)
167                         hint = find_ref_by_name(refs, refname);
168                 if (!hint) {
169                         warning("remote reported status on unknown ref: %s",
170                                         refname);
171                         continue;
172                 }
173                 if (hint->status != REF_STATUS_EXPECTING_REPORT) {
174                         warning("remote reported status on unexpected ref: %s",
175                                         refname);
176                         continue;
177                 }
178
179                 if (line[0] == 'o' && line[1] == 'k')
180                         hint->status = REF_STATUS_OK;
181                 else {
182                         hint->status = REF_STATUS_REMOTE_REJECT;
183                         ret = -1;
184                 }
185                 if (msg)
186                         hint->remote_status = xstrdup(msg);
187                 /* start our next search from the next ref */
188                 hint = hint->next;
189         }
190         return ret;
191 }
192
193 static int sideband_demux(int in, int out, void *data)
194 {
195         int *fd = data, ret;
196 #ifdef NO_PTHREADS
197         close(fd[1]);
198 #endif
199         ret = recv_sideband("send-pack", fd[0], out);
200         close(out);
201         return ret;
202 }
203
204 static int advertise_shallow_grafts_cb(const struct commit_graft *graft, void *cb)
205 {
206         struct strbuf *sb = cb;
207         if (graft->nr_parent == -1)
208                 packet_buf_write(sb, "shallow %s\n", oid_to_hex(&graft->oid));
209         return 0;
210 }
211
212 static void advertise_shallow_grafts_buf(struct strbuf *sb)
213 {
214         if (!is_repository_shallow())
215                 return;
216         for_each_commit_graft(advertise_shallow_grafts_cb, sb);
217 }
218
219 #define CHECK_REF_NO_PUSH -1
220 #define CHECK_REF_STATUS_REJECTED -2
221 #define CHECK_REF_UPTODATE -3
222 static int check_to_send_update(const struct ref *ref, const struct send_pack_args *args)
223 {
224         if (!ref->peer_ref && !args->send_mirror)
225                 return CHECK_REF_NO_PUSH;
226
227         /* Check for statuses set by set_ref_status_for_push() */
228         switch (ref->status) {
229         case REF_STATUS_REJECT_NONFASTFORWARD:
230         case REF_STATUS_REJECT_ALREADY_EXISTS:
231         case REF_STATUS_REJECT_FETCH_FIRST:
232         case REF_STATUS_REJECT_NEEDS_FORCE:
233         case REF_STATUS_REJECT_STALE:
234         case REF_STATUS_REJECT_NODELETE:
235                 return CHECK_REF_STATUS_REJECTED;
236         case REF_STATUS_UPTODATE:
237                 return CHECK_REF_UPTODATE;
238         default:
239                 return 0;
240         }
241 }
242
243 /*
244  * the beginning of the next line, or the end of buffer.
245  *
246  * NEEDSWORK: perhaps move this to git-compat-util.h or somewhere and
247  * convert many similar uses found by "git grep -A4 memchr".
248  */
249 static const char *next_line(const char *line, size_t len)
250 {
251         const char *nl = memchr(line, '\n', len);
252         if (!nl)
253                 return line + len; /* incomplete line */
254         return nl + 1;
255 }
256
257 static int generate_push_cert(struct strbuf *req_buf,
258                               const struct ref *remote_refs,
259                               struct send_pack_args *args,
260                               const char *cap_string,
261                               const char *push_cert_nonce)
262 {
263         const struct ref *ref;
264         char *signing_key = xstrdup(get_signing_key());
265         const char *cp, *np;
266         struct strbuf cert = STRBUF_INIT;
267         int update_seen = 0;
268
269         strbuf_addf(&cert, "certificate version 0.1\n");
270         strbuf_addf(&cert, "pusher %s ", signing_key);
271         datestamp(&cert);
272         strbuf_addch(&cert, '\n');
273         if (args->url && *args->url) {
274                 char *anon_url = transport_anonymize_url(args->url);
275                 strbuf_addf(&cert, "pushee %s\n", anon_url);
276                 free(anon_url);
277         }
278         if (push_cert_nonce[0])
279                 strbuf_addf(&cert, "nonce %s\n", push_cert_nonce);
280         strbuf_addstr(&cert, "\n");
281
282         for (ref = remote_refs; ref; ref = ref->next) {
283                 if (check_to_send_update(ref, args) < 0)
284                         continue;
285                 update_seen = 1;
286                 strbuf_addf(&cert, "%s %s %s\n",
287                             oid_to_hex(&ref->old_oid),
288                             oid_to_hex(&ref->new_oid),
289                             ref->name);
290         }
291         if (!update_seen)
292                 goto free_return;
293
294         if (sign_buffer(&cert, &cert, signing_key))
295                 die(_("failed to sign the push certificate"));
296
297         packet_buf_write(req_buf, "push-cert%c%s", 0, cap_string);
298         for (cp = cert.buf; cp < cert.buf + cert.len; cp = np) {
299                 np = next_line(cp, cert.buf + cert.len - cp);
300                 packet_buf_write(req_buf,
301                                  "%.*s", (int)(np - cp), cp);
302         }
303         packet_buf_write(req_buf, "push-cert-end\n");
304
305 free_return:
306         free(signing_key);
307         strbuf_release(&cert);
308         return update_seen;
309 }
310
311
312 static int atomic_push_failure(struct send_pack_args *args,
313                                struct ref *remote_refs,
314                                struct ref *failing_ref)
315 {
316         struct ref *ref;
317         /* Mark other refs as failed */
318         for (ref = remote_refs; ref; ref = ref->next) {
319                 if (!ref->peer_ref && !args->send_mirror)
320                         continue;
321
322                 switch (ref->status) {
323                 case REF_STATUS_EXPECTING_REPORT:
324                         ref->status = REF_STATUS_ATOMIC_PUSH_FAILED;
325                         continue;
326                 default:
327                         break; /* do nothing */
328                 }
329         }
330         return error("atomic push failed for ref %s. status: %d\n",
331                      failing_ref->name, failing_ref->status);
332 }
333
334 #define NONCE_LEN_LIMIT 256
335
336 static void reject_invalid_nonce(const char *nonce, int len)
337 {
338         int i = 0;
339
340         if (NONCE_LEN_LIMIT <= len)
341                 die("the receiving end asked to sign an invalid nonce <%.*s>",
342                     len, nonce);
343
344         for (i = 0; i < len; i++) {
345                 int ch = nonce[i] & 0xFF;
346                 if (isalnum(ch) ||
347                     ch == '-' || ch == '.' ||
348                     ch == '/' || ch == '+' ||
349                     ch == '=' || ch == '_')
350                         continue;
351                 die("the receiving end asked to sign an invalid nonce <%.*s>",
352                     len, nonce);
353         }
354 }
355
356 int send_pack(struct send_pack_args *args,
357               int fd[], struct child_process *conn,
358               struct ref *remote_refs,
359               struct sha1_array *extra_have)
360 {
361         int in = fd[0];
362         int out = fd[1];
363         struct strbuf req_buf = STRBUF_INIT;
364         struct strbuf cap_buf = STRBUF_INIT;
365         struct ref *ref;
366         int need_pack_data = 0;
367         int allow_deleting_refs = 0;
368         int status_report = 0;
369         int use_sideband = 0;
370         int quiet_supported = 0;
371         int agent_supported = 0;
372         int use_atomic = 0;
373         int atomic_supported = 0;
374         unsigned cmds_sent = 0;
375         int ret;
376         struct async demux;
377         const char *push_cert_nonce = NULL;
378
379         /* Does the other end support the reporting? */
380         if (server_supports("report-status"))
381                 status_report = 1;
382         if (server_supports("delete-refs"))
383                 allow_deleting_refs = 1;
384         if (server_supports("ofs-delta"))
385                 args->use_ofs_delta = 1;
386         if (server_supports("side-band-64k"))
387                 use_sideband = 1;
388         if (server_supports("quiet"))
389                 quiet_supported = 1;
390         if (server_supports("agent"))
391                 agent_supported = 1;
392         if (server_supports("no-thin"))
393                 args->use_thin_pack = 0;
394         if (server_supports("atomic"))
395                 atomic_supported = 1;
396
397         if (args->push_cert != SEND_PACK_PUSH_CERT_NEVER) {
398                 int len;
399                 push_cert_nonce = server_feature_value("push-cert", &len);
400                 if (push_cert_nonce) {
401                         reject_invalid_nonce(push_cert_nonce, len);
402                         push_cert_nonce = xmemdupz(push_cert_nonce, len);
403                 } else if (args->push_cert == SEND_PACK_PUSH_CERT_ALWAYS) {
404                         die(_("the receiving end does not support --signed push"));
405                 } else if (args->push_cert == SEND_PACK_PUSH_CERT_IF_ASKED) {
406                         warning(_("not sending a push certificate since the"
407                                   " receiving end does not support --signed"
408                                   " push"));
409                 }
410         }
411
412         if (!remote_refs) {
413                 fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
414                         "Perhaps you should specify a branch such as 'master'.\n");
415                 return 0;
416         }
417         if (args->atomic && !atomic_supported)
418                 die(_("the receiving end does not support --atomic push"));
419
420         use_atomic = atomic_supported && args->atomic;
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 (agent_supported)
431                 strbuf_addf(&cap_buf, " agent=%s", git_user_agent_sanitized());
432
433         /*
434          * NEEDSWORK: why does delete-refs have to be so specific to
435          * send-pack machinery that set_ref_status_for_push() cannot
436          * set this bit for us???
437          */
438         for (ref = remote_refs; ref; ref = ref->next)
439                 if (ref->deletion && !allow_deleting_refs)
440                         ref->status = REF_STATUS_REJECT_NODELETE;
441
442         if (!args->dry_run)
443                 advertise_shallow_grafts_buf(&req_buf);
444
445         if (!args->dry_run && push_cert_nonce)
446                 cmds_sent = generate_push_cert(&req_buf, remote_refs, args,
447                                                cap_buf.buf, push_cert_nonce);
448
449         /*
450          * Clear the status for each ref and see if we need to send
451          * the pack data.
452          */
453         for (ref = remote_refs; ref; ref = ref->next) {
454                 switch (check_to_send_update(ref, args)) {
455                 case 0: /* no error */
456                         break;
457                 case CHECK_REF_STATUS_REJECTED:
458                         /*
459                          * When we know the server would reject a ref update if
460                          * we were to send it and we're trying to send the refs
461                          * atomically, abort the whole operation.
462                          */
463                         if (use_atomic)
464                                 return atomic_push_failure(args, remote_refs, ref);
465                         /* Fallthrough for non atomic case. */
466                 default:
467                         continue;
468                 }
469                 if (!ref->deletion)
470                         need_pack_data = 1;
471
472                 if (args->dry_run || !status_report)
473                         ref->status = REF_STATUS_OK;
474                 else
475                         ref->status = REF_STATUS_EXPECTING_REPORT;
476         }
477
478         /*
479          * Finally, tell the other end!
480          */
481         for (ref = remote_refs; ref; ref = ref->next) {
482                 char *old_hex, *new_hex;
483
484                 if (args->dry_run || push_cert_nonce)
485                         continue;
486
487                 if (check_to_send_update(ref, args) < 0)
488                         continue;
489
490                 old_hex = oid_to_hex(&ref->old_oid);
491                 new_hex = oid_to_hex(&ref->new_oid);
492                 if (!cmds_sent) {
493                         packet_buf_write(&req_buf,
494                                          "%s %s %s%c%s",
495                                          old_hex, new_hex, ref->name, 0,
496                                          cap_buf.buf);
497                         cmds_sent = 1;
498                 } else {
499                         packet_buf_write(&req_buf, "%s %s %s",
500                                          old_hex, new_hex, ref->name);
501                 }
502         }
503
504         if (args->stateless_rpc) {
505                 if (!args->dry_run && (cmds_sent || is_repository_shallow())) {
506                         packet_buf_flush(&req_buf);
507                         send_sideband(out, -1, req_buf.buf, req_buf.len, LARGE_PACKET_MAX);
508                 }
509         } else {
510                 write_or_die(out, req_buf.buf, req_buf.len);
511                 packet_flush(out);
512         }
513         strbuf_release(&req_buf);
514         strbuf_release(&cap_buf);
515
516         if (use_sideband && cmds_sent) {
517                 memset(&demux, 0, sizeof(demux));
518                 demux.proc = sideband_demux;
519                 demux.data = fd;
520                 demux.out = -1;
521                 if (start_async(&demux))
522                         die("send-pack: unable to fork off sideband demultiplexer");
523                 in = demux.out;
524         }
525
526         if (need_pack_data && cmds_sent) {
527                 if (pack_objects(out, remote_refs, extra_have, args) < 0) {
528                         for (ref = remote_refs; ref; ref = ref->next)
529                                 ref->status = REF_STATUS_NONE;
530                         if (args->stateless_rpc)
531                                 close(out);
532                         if (git_connection_is_socket(conn))
533                                 shutdown(fd[0], SHUT_WR);
534                         if (use_sideband)
535                                 finish_async(&demux);
536                         fd[1] = -1;
537                         return -1;
538                 }
539                 if (!args->stateless_rpc)
540                         /* Closed by pack_objects() via start_command() */
541                         fd[1] = -1;
542         }
543         if (args->stateless_rpc && cmds_sent)
544                 packet_flush(out);
545
546         if (status_report && cmds_sent)
547                 ret = receive_status(in, remote_refs);
548         else
549                 ret = 0;
550         if (args->stateless_rpc)
551                 packet_flush(out);
552
553         if (use_sideband && cmds_sent) {
554                 if (finish_async(&demux)) {
555                         error("error in sideband demultiplexer");
556                         ret = -1;
557                 }
558                 close(demux.out);
559         }
560
561         if (ret < 0)
562                 return ret;
563
564         if (args->porcelain)
565                 return 0;
566
567         for (ref = remote_refs; ref; ref = ref->next) {
568                 switch (ref->status) {
569                 case REF_STATUS_NONE:
570                 case REF_STATUS_UPTODATE:
571                 case REF_STATUS_OK:
572                         break;
573                 default:
574                         return -1;
575                 }
576         }
577         return 0;
578 }