Code

send-pack: avoid deadlock when pack-object dies early
[git.git] / builtin-send-pack.c
1 #include "cache.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 "send-pack.h"
9 #include "quote.h"
11 static const char send_pack_usage[] =
12 "git send-pack [--all | --mirror] [--dry-run] [--force] [--receive-pack=<git-receive-pack>] [--verbose] [--thin] [<host>:]<directory> [<ref>...]\n"
13 "  --all and explicit <ref> specification are mutually exclusive.";
15 static struct send_pack_args args;
17 static int feed_object(const unsigned char *sha1, int fd, int negative)
18 {
19         char buf[42];
21         if (negative && !has_sha1_file(sha1))
22                 return 1;
24         memcpy(buf + negative, sha1_to_hex(sha1), 40);
25         if (negative)
26                 buf[0] = '^';
27         buf[40 + negative] = '\n';
28         return write_or_whine(fd, buf, 41 + negative, "send-pack: send refs");
29 }
31 /*
32  * Make a pack stream and spit it out into file descriptor fd
33  */
34 static int pack_objects(int fd, struct ref *refs, struct extra_have_objects *extra, struct send_pack_args *args)
35 {
36         /*
37          * The child becomes pack-objects --revs; we feed
38          * the revision parameters to it via its stdin and
39          * let its stdout go back to the other end.
40          */
41         const char *argv[] = {
42                 "pack-objects",
43                 "--all-progress-implied",
44                 "--revs",
45                 "--stdout",
46                 NULL,
47                 NULL,
48                 NULL,
49                 NULL,
50         };
51         struct child_process po;
52         int i;
54         i = 4;
55         if (args->use_thin_pack)
56                 argv[i++] = "--thin";
57         if (args->use_ofs_delta)
58                 argv[i++] = "--delta-base-offset";
59         if (args->quiet)
60                 argv[i++] = "-q";
61         memset(&po, 0, sizeof(po));
62         po.argv = argv;
63         po.in = -1;
64         po.out = args->stateless_rpc ? -1 : fd;
65         po.git_cmd = 1;
66         if (start_command(&po))
67                 die_errno("git pack-objects failed");
69         /*
70          * We feed the pack-objects we just spawned with revision
71          * parameters by writing to the pipe.
72          */
73         for (i = 0; i < extra->nr; i++)
74                 if (!feed_object(extra->array[i], po.in, 1))
75                         break;
77         while (refs) {
78                 if (!is_null_sha1(refs->old_sha1) &&
79                     !feed_object(refs->old_sha1, po.in, 1))
80                         break;
81                 if (!is_null_sha1(refs->new_sha1) &&
82                     !feed_object(refs->new_sha1, po.in, 0))
83                         break;
84                 refs = refs->next;
85         }
87         close(po.in);
89         if (args->stateless_rpc) {
90                 char *buf = xmalloc(LARGE_PACKET_MAX);
91                 while (1) {
92                         ssize_t n = xread(po.out, buf, LARGE_PACKET_MAX);
93                         if (n <= 0)
94                                 break;
95                         send_sideband(fd, -1, buf, n, LARGE_PACKET_MAX);
96                 }
97                 free(buf);
98                 close(po.out);
99                 po.out = -1;
100                 close(fd);
101         }
103         if (finish_command(&po))
104                 return error("pack-objects died with strange error");
105         return 0;
108 static int receive_status(int in, struct ref *refs)
110         struct ref *hint;
111         char line[1000];
112         int ret = 0;
113         int len = packet_read_line(in, line, sizeof(line));
114         if (len < 10 || memcmp(line, "unpack ", 7))
115                 return error("did not receive remote status");
116         if (memcmp(line, "unpack ok\n", 10)) {
117                 char *p = line + strlen(line) - 1;
118                 if (*p == '\n')
119                         *p = '\0';
120                 error("unpack failed: %s", line + 7);
121                 ret = -1;
122         }
123         hint = NULL;
124         while (1) {
125                 char *refname;
126                 char *msg;
127                 len = packet_read_line(in, line, sizeof(line));
128                 if (!len)
129                         break;
130                 if (len < 3 ||
131                     (memcmp(line, "ok ", 3) && memcmp(line, "ng ", 3))) {
132                         fprintf(stderr, "protocol error: %s\n", line);
133                         ret = -1;
134                         break;
135                 }
137                 line[strlen(line)-1] = '\0';
138                 refname = line + 3;
139                 msg = strchr(refname, ' ');
140                 if (msg)
141                         *msg++ = '\0';
143                 /* first try searching at our hint, falling back to all refs */
144                 if (hint)
145                         hint = find_ref_by_name(hint, refname);
146                 if (!hint)
147                         hint = find_ref_by_name(refs, refname);
148                 if (!hint) {
149                         warning("remote reported status on unknown ref: %s",
150                                         refname);
151                         continue;
152                 }
153                 if (hint->status != REF_STATUS_EXPECTING_REPORT) {
154                         warning("remote reported status on unexpected ref: %s",
155                                         refname);
156                         continue;
157                 }
159                 if (line[0] == 'o' && line[1] == 'k')
160                         hint->status = REF_STATUS_OK;
161                 else {
162                         hint->status = REF_STATUS_REMOTE_REJECT;
163                         ret = -1;
164                 }
165                 if (msg)
166                         hint->remote_status = xstrdup(msg);
167                 /* start our next search from the next ref */
168                 hint = hint->next;
169         }
170         return ret;
173 static void update_tracking_ref(struct remote *remote, struct ref *ref)
175         struct refspec rs;
177         if (ref->status != REF_STATUS_OK && ref->status != REF_STATUS_UPTODATE)
178                 return;
180         rs.src = ref->name;
181         rs.dst = NULL;
183         if (!remote_find_tracking(remote, &rs)) {
184                 if (args.verbose)
185                         fprintf(stderr, "updating local tracking ref '%s'\n", rs.dst);
186                 if (ref->deletion) {
187                         delete_ref(rs.dst, NULL, 0);
188                 } else
189                         update_ref("update by push", rs.dst,
190                                         ref->new_sha1, NULL, 0, 0);
191                 free(rs.dst);
192         }
195 #define SUMMARY_WIDTH (2 * DEFAULT_ABBREV + 3)
197 static void print_ref_status(char flag, const char *summary, struct ref *to, struct ref *from, const char *msg)
199         fprintf(stderr, " %c %-*s ", flag, SUMMARY_WIDTH, summary);
200         if (from)
201                 fprintf(stderr, "%s -> %s", prettify_refname(from->name), prettify_refname(to->name));
202         else
203                 fputs(prettify_refname(to->name), stderr);
204         if (msg) {
205                 fputs(" (", stderr);
206                 fputs(msg, stderr);
207                 fputc(')', stderr);
208         }
209         fputc('\n', stderr);
212 static const char *status_abbrev(unsigned char sha1[20])
214         return find_unique_abbrev(sha1, DEFAULT_ABBREV);
217 static void print_ok_ref_status(struct ref *ref)
219         if (ref->deletion)
220                 print_ref_status('-', "[deleted]", ref, NULL, NULL);
221         else if (is_null_sha1(ref->old_sha1))
222                 print_ref_status('*',
223                         (!prefixcmp(ref->name, "refs/tags/") ? "[new tag]" :
224                           "[new branch]"),
225                         ref, ref->peer_ref, NULL);
226         else {
227                 char quickref[84];
228                 char type;
229                 const char *msg;
231                 strcpy(quickref, status_abbrev(ref->old_sha1));
232                 if (ref->nonfastforward) {
233                         strcat(quickref, "...");
234                         type = '+';
235                         msg = "forced update";
236                 } else {
237                         strcat(quickref, "..");
238                         type = ' ';
239                         msg = NULL;
240                 }
241                 strcat(quickref, status_abbrev(ref->new_sha1));
243                 print_ref_status(type, quickref, ref, ref->peer_ref, msg);
244         }
247 static int print_one_push_status(struct ref *ref, const char *dest, int count)
249         if (!count)
250                 fprintf(stderr, "To %s\n", dest);
252         switch(ref->status) {
253         case REF_STATUS_NONE:
254                 print_ref_status('X', "[no match]", ref, NULL, NULL);
255                 break;
256         case REF_STATUS_REJECT_NODELETE:
257                 print_ref_status('!', "[rejected]", ref, NULL,
258                                 "remote does not support deleting refs");
259                 break;
260         case REF_STATUS_UPTODATE:
261                 print_ref_status('=', "[up to date]", ref,
262                                 ref->peer_ref, NULL);
263                 break;
264         case REF_STATUS_REJECT_NONFASTFORWARD:
265                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
266                                 "non-fast-forward");
267                 break;
268         case REF_STATUS_REMOTE_REJECT:
269                 print_ref_status('!', "[remote rejected]", ref,
270                                 ref->deletion ? NULL : ref->peer_ref,
271                                 ref->remote_status);
272                 break;
273         case REF_STATUS_EXPECTING_REPORT:
274                 print_ref_status('!', "[remote failure]", ref,
275                                 ref->deletion ? NULL : ref->peer_ref,
276                                 "remote failed to report status");
277                 break;
278         case REF_STATUS_OK:
279                 print_ok_ref_status(ref);
280                 break;
281         }
283         return 1;
286 static void print_push_status(const char *dest, struct ref *refs)
288         struct ref *ref;
289         int n = 0;
291         if (args.verbose) {
292                 for (ref = refs; ref; ref = ref->next)
293                         if (ref->status == REF_STATUS_UPTODATE)
294                                 n += print_one_push_status(ref, dest, n);
295         }
297         for (ref = refs; ref; ref = ref->next)
298                 if (ref->status == REF_STATUS_OK)
299                         n += print_one_push_status(ref, dest, n);
301         for (ref = refs; ref; ref = ref->next) {
302                 if (ref->status != REF_STATUS_NONE &&
303                     ref->status != REF_STATUS_UPTODATE &&
304                     ref->status != REF_STATUS_OK)
305                         n += print_one_push_status(ref, dest, n);
306         }
309 static int refs_pushed(struct ref *ref)
311         for (; ref; ref = ref->next) {
312                 switch(ref->status) {
313                 case REF_STATUS_NONE:
314                 case REF_STATUS_UPTODATE:
315                         break;
316                 default:
317                         return 1;
318                 }
319         }
320         return 0;
323 static void print_helper_status(struct ref *ref)
325         struct strbuf buf = STRBUF_INIT;
327         for (; ref; ref = ref->next) {
328                 const char *msg = NULL;
329                 const char *res;
331                 switch(ref->status) {
332                 case REF_STATUS_NONE:
333                         res = "error";
334                         msg = "no match";
335                         break;
337                 case REF_STATUS_OK:
338                         res = "ok";
339                         break;
341                 case REF_STATUS_UPTODATE:
342                         res = "ok";
343                         msg = "up to date";
344                         break;
346                 case REF_STATUS_REJECT_NONFASTFORWARD:
347                         res = "error";
348                         msg = "non-fast forward";
349                         break;
351                 case REF_STATUS_REJECT_NODELETE:
352                 case REF_STATUS_REMOTE_REJECT:
353                         res = "error";
354                         break;
356                 case REF_STATUS_EXPECTING_REPORT:
357                 default:
358                         continue;
359                 }
361                 strbuf_reset(&buf);
362                 strbuf_addf(&buf, "%s %s", res, ref->name);
363                 if (ref->remote_status)
364                         msg = ref->remote_status;
365                 if (msg) {
366                         strbuf_addch(&buf, ' ');
367                         quote_two_c_style(&buf, "", msg, 0);
368                 }
369                 strbuf_addch(&buf, '\n');
371                 safe_write(1, buf.buf, buf.len);
372         }
373         strbuf_release(&buf);
376 static int sideband_demux(int in, int out, void *data)
378         int *fd = data;
379 #ifndef WIN32
380         close(fd[1]);
381 #endif
382         int ret = recv_sideband("send-pack", fd[0], out);
383         close(out);
384         return ret;
387 int send_pack(struct send_pack_args *args,
388               int fd[], struct child_process *conn,
389               struct ref *remote_refs,
390               struct extra_have_objects *extra_have)
392         int in = fd[0];
393         int out = fd[1];
394         struct strbuf req_buf = STRBUF_INIT;
395         struct ref *ref;
396         int new_refs;
397         int allow_deleting_refs = 0;
398         int status_report = 0;
399         int use_sideband = 0;
400         unsigned cmds_sent = 0;
401         int ret;
402         struct async demux;
404         /* Does the other end support the reporting? */
405         if (server_supports("report-status"))
406                 status_report = 1;
407         if (server_supports("delete-refs"))
408                 allow_deleting_refs = 1;
409         if (server_supports("ofs-delta"))
410                 args->use_ofs_delta = 1;
411         if (server_supports("side-band-64k"))
412                 use_sideband = 1;
414         if (!remote_refs) {
415                 fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
416                         "Perhaps you should specify a branch such as 'master'.\n");
417                 return 0;
418         }
420         /*
421          * Finally, tell the other end!
422          */
423         new_refs = 0;
424         for (ref = remote_refs; ref; ref = ref->next) {
426                 if (ref->peer_ref)
427                         hashcpy(ref->new_sha1, ref->peer_ref->new_sha1);
428                 else if (!args->send_mirror)
429                         continue;
431                 ref->deletion = is_null_sha1(ref->new_sha1);
432                 if (ref->deletion && !allow_deleting_refs) {
433                         ref->status = REF_STATUS_REJECT_NODELETE;
434                         continue;
435                 }
436                 if (!ref->deletion &&
437                     !hashcmp(ref->old_sha1, ref->new_sha1)) {
438                         ref->status = REF_STATUS_UPTODATE;
439                         continue;
440                 }
442                 /* This part determines what can overwrite what.
443                  * The rules are:
444                  *
445                  * (0) you can always use --force or +A:B notation to
446                  *     selectively force individual ref pairs.
447                  *
448                  * (1) if the old thing does not exist, it is OK.
449                  *
450                  * (2) if you do not have the old thing, you are not allowed
451                  *     to overwrite it; you would not know what you are losing
452                  *     otherwise.
453                  *
454                  * (3) if both new and old are commit-ish, and new is a
455                  *     descendant of old, it is OK.
456                  *
457                  * (4) regardless of all of the above, removing :B is
458                  *     always allowed.
459                  */
461                 ref->nonfastforward =
462                     !ref->deletion &&
463                     !is_null_sha1(ref->old_sha1) &&
464                     (!has_sha1_file(ref->old_sha1)
465                       || !ref_newer(ref->new_sha1, ref->old_sha1));
467                 if (ref->nonfastforward && !ref->force && !args->force_update) {
468                         ref->status = REF_STATUS_REJECT_NONFASTFORWARD;
469                         continue;
470                 }
472                 if (!ref->deletion)
473                         new_refs++;
475                 if (args->dry_run) {
476                         ref->status = REF_STATUS_OK;
477                 } else {
478                         char *old_hex = sha1_to_hex(ref->old_sha1);
479                         char *new_hex = sha1_to_hex(ref->new_sha1);
481                         if (!cmds_sent && (status_report || use_sideband)) {
482                                 packet_buf_write(&req_buf, "%s %s %s%c%s%s",
483                                         old_hex, new_hex, ref->name, 0,
484                                         status_report ? " report-status" : "",
485                                         use_sideband ? " side-band-64k" : "");
486                         }
487                         else
488                                 packet_buf_write(&req_buf, "%s %s %s",
489                                         old_hex, new_hex, ref->name);
490                         ref->status = status_report ?
491                                 REF_STATUS_EXPECTING_REPORT :
492                                 REF_STATUS_OK;
493                         cmds_sent++;
494                 }
495         }
497         if (args->stateless_rpc) {
498                 if (!args->dry_run && cmds_sent) {
499                         packet_buf_flush(&req_buf);
500                         send_sideband(out, -1, req_buf.buf, req_buf.len, LARGE_PACKET_MAX);
501                 }
502         } else {
503                 safe_write(out, req_buf.buf, req_buf.len);
504                 packet_flush(out);
505         }
506         strbuf_release(&req_buf);
508         if (use_sideband && cmds_sent) {
509                 memset(&demux, 0, sizeof(demux));
510                 demux.proc = sideband_demux;
511                 demux.data = fd;
512                 demux.out = -1;
513                 if (start_async(&demux))
514                         die("receive-pack: unable to fork off sideband demultiplexer");
515                 in = demux.out;
516         }
518         if (new_refs && cmds_sent) {
519                 if (pack_objects(out, remote_refs, extra_have, args) < 0) {
520                         for (ref = remote_refs; ref; ref = ref->next)
521                                 ref->status = REF_STATUS_NONE;
522                         if (use_sideband)
523                                 finish_async(&demux);
524                         return -1;
525                 }
526         }
527         if (args->stateless_rpc && cmds_sent)
528                 packet_flush(out);
530         if (status_report && cmds_sent)
531                 ret = receive_status(in, remote_refs);
532         else
533                 ret = 0;
534         if (args->stateless_rpc)
535                 packet_flush(out);
537         if (use_sideband && cmds_sent) {
538                 if (finish_async(&demux)) {
539                         error("error in sideband demultiplexer");
540                         ret = -1;
541                 }
542                 close(demux.out);
543         }
545         if (ret < 0)
546                 return ret;
547         for (ref = remote_refs; ref; ref = ref->next) {
548                 switch (ref->status) {
549                 case REF_STATUS_NONE:
550                 case REF_STATUS_UPTODATE:
551                 case REF_STATUS_OK:
552                         break;
553                 default:
554                         return -1;
555                 }
556         }
557         return 0;
560 static void verify_remote_names(int nr_heads, const char **heads)
562         int i;
564         for (i = 0; i < nr_heads; i++) {
565                 const char *local = heads[i];
566                 const char *remote = strrchr(heads[i], ':');
568                 if (*local == '+')
569                         local++;
571                 /* A matching refspec is okay.  */
572                 if (remote == local && remote[1] == '\0')
573                         continue;
575                 remote = remote ? (remote + 1) : local;
576                 switch (check_ref_format(remote)) {
577                 case 0: /* ok */
578                 case CHECK_REF_FORMAT_ONELEVEL:
579                         /* ok but a single level -- that is fine for
580                          * a match pattern.
581                          */
582                 case CHECK_REF_FORMAT_WILDCARD:
583                         /* ok but ends with a pattern-match character */
584                         continue;
585                 }
586                 die("remote part of refspec is not a valid name in %s",
587                     heads[i]);
588         }
591 int cmd_send_pack(int argc, const char **argv, const char *prefix)
593         int i, nr_refspecs = 0;
594         const char **refspecs = NULL;
595         const char *remote_name = NULL;
596         struct remote *remote = NULL;
597         const char *dest = NULL;
598         int fd[2];
599         struct child_process *conn;
600         struct extra_have_objects extra_have;
601         struct ref *remote_refs, *local_refs;
602         int ret;
603         int helper_status = 0;
604         int send_all = 0;
605         const char *receivepack = "git-receive-pack";
606         int flags;
608         argv++;
609         for (i = 1; i < argc; i++, argv++) {
610                 const char *arg = *argv;
612                 if (*arg == '-') {
613                         if (!prefixcmp(arg, "--receive-pack=")) {
614                                 receivepack = arg + 15;
615                                 continue;
616                         }
617                         if (!prefixcmp(arg, "--exec=")) {
618                                 receivepack = arg + 7;
619                                 continue;
620                         }
621                         if (!prefixcmp(arg, "--remote=")) {
622                                 remote_name = arg + 9;
623                                 continue;
624                         }
625                         if (!strcmp(arg, "--all")) {
626                                 send_all = 1;
627                                 continue;
628                         }
629                         if (!strcmp(arg, "--dry-run")) {
630                                 args.dry_run = 1;
631                                 continue;
632                         }
633                         if (!strcmp(arg, "--mirror")) {
634                                 args.send_mirror = 1;
635                                 continue;
636                         }
637                         if (!strcmp(arg, "--force")) {
638                                 args.force_update = 1;
639                                 continue;
640                         }
641                         if (!strcmp(arg, "--verbose")) {
642                                 args.verbose = 1;
643                                 continue;
644                         }
645                         if (!strcmp(arg, "--thin")) {
646                                 args.use_thin_pack = 1;
647                                 continue;
648                         }
649                         if (!strcmp(arg, "--stateless-rpc")) {
650                                 args.stateless_rpc = 1;
651                                 continue;
652                         }
653                         if (!strcmp(arg, "--helper-status")) {
654                                 helper_status = 1;
655                                 continue;
656                         }
657                         usage(send_pack_usage);
658                 }
659                 if (!dest) {
660                         dest = arg;
661                         continue;
662                 }
663                 refspecs = (const char **) argv;
664                 nr_refspecs = argc - i;
665                 break;
666         }
667         if (!dest)
668                 usage(send_pack_usage);
669         /*
670          * --all and --mirror are incompatible; neither makes sense
671          * with any refspecs.
672          */
673         if ((refspecs && (send_all || args.send_mirror)) ||
674             (send_all && args.send_mirror))
675                 usage(send_pack_usage);
677         if (remote_name) {
678                 remote = remote_get(remote_name);
679                 if (!remote_has_url(remote, dest)) {
680                         die("Destination %s is not a uri for %s",
681                             dest, remote_name);
682                 }
683         }
685         if (args.stateless_rpc) {
686                 conn = NULL;
687                 fd[0] = 0;
688                 fd[1] = 1;
689         } else {
690                 conn = git_connect(fd, dest, receivepack,
691                         args.verbose ? CONNECT_VERBOSE : 0);
692         }
694         memset(&extra_have, 0, sizeof(extra_have));
696         get_remote_heads(fd[0], &remote_refs, 0, NULL, REF_NORMAL,
697                          &extra_have);
699         verify_remote_names(nr_refspecs, refspecs);
701         local_refs = get_local_heads();
703         flags = MATCH_REFS_NONE;
705         if (send_all)
706                 flags |= MATCH_REFS_ALL;
707         if (args.send_mirror)
708                 flags |= MATCH_REFS_MIRROR;
710         /* match them up */
711         if (match_refs(local_refs, &remote_refs, nr_refspecs, refspecs, flags))
712                 return -1;
714         ret = send_pack(&args, fd, conn, remote_refs, &extra_have);
716         if (helper_status)
717                 print_helper_status(remote_refs);
719         close(fd[1]);
720         close(fd[0]);
722         ret |= finish_connect(conn);
724         if (!helper_status)
725                 print_push_status(dest, remote_refs);
727         if (!args.dry_run && remote) {
728                 struct ref *ref;
729                 for (ref = remote_refs; ref; ref = ref->next)
730                         update_tracking_ref(remote, ref);
731         }
733         if (!ret && !refs_pushed(remote_refs))
734                 fprintf(stderr, "Everything up-to-date\n");
736         return ret;