Merge branch 'sh/maint-rebase3'
[git] / builtin-receive-pack.c
1 #include "cache.h"
2 #include "pack.h"
3 #include "refs.h"
4 #include "pkt-line.h"
5 #include "run-command.h"
6 #include "exec_cmd.h"
7 #include "commit.h"
8 #include "object.h"
9 #include "remote.h"
10 #include "transport.h"
11
12 static const char receive_pack_usage[] = "git-receive-pack <git-dir>";
13
14 static int deny_non_fast_forwards = 0;
15 static int receive_fsck_objects;
16 static int receive_unpack_limit = -1;
17 static int transfer_unpack_limit = -1;
18 static int unpack_limit = 100;
19 static int report_status;
20
21 static char capabilities[] = " report-status delete-refs ";
22 static int capabilities_sent;
23
24 static int receive_pack_config(const char *var, const char *value, void *cb)
25 {
26         if (strcmp(var, "receive.denynonfastforwards") == 0) {
27                 deny_non_fast_forwards = git_config_bool(var, value);
28                 return 0;
29         }
30
31         if (strcmp(var, "receive.unpacklimit") == 0) {
32                 receive_unpack_limit = git_config_int(var, value);
33                 return 0;
34         }
35
36         if (strcmp(var, "transfer.unpacklimit") == 0) {
37                 transfer_unpack_limit = git_config_int(var, value);
38                 return 0;
39         }
40
41         if (strcmp(var, "receive.fsckobjects") == 0) {
42                 receive_fsck_objects = git_config_bool(var, value);
43                 return 0;
44         }
45
46         return git_default_config(var, value, cb);
47 }
48
49 static int show_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
50 {
51         if (capabilities_sent)
52                 packet_write(1, "%s %s\n", sha1_to_hex(sha1), path);
53         else
54                 packet_write(1, "%s %s%c%s\n",
55                              sha1_to_hex(sha1), path, 0, capabilities);
56         capabilities_sent = 1;
57         return 0;
58 }
59
60 static void write_head_info(void)
61 {
62         for_each_ref(show_ref, NULL);
63         if (!capabilities_sent)
64                 show_ref("capabilities^{}", null_sha1, 0, NULL);
65
66 }
67
68 struct command {
69         struct command *next;
70         const char *error_string;
71         unsigned char old_sha1[20];
72         unsigned char new_sha1[20];
73         char ref_name[FLEX_ARRAY]; /* more */
74 };
75
76 static struct command *commands;
77
78 static const char pre_receive_hook[] = "hooks/pre-receive";
79 static const char post_receive_hook[] = "hooks/post-receive";
80
81 static int hook_status(int code, const char *hook_name)
82 {
83         switch (code) {
84         case 0:
85                 return 0;
86         case -ERR_RUN_COMMAND_FORK:
87                 return error("hook fork failed");
88         case -ERR_RUN_COMMAND_EXEC:
89                 return error("hook execute failed");
90         case -ERR_RUN_COMMAND_PIPE:
91                 return error("hook pipe failed");
92         case -ERR_RUN_COMMAND_WAITPID:
93                 return error("waitpid failed");
94         case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
95                 return error("waitpid is confused");
96         case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
97                 return error("%s died of signal", hook_name);
98         case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
99                 return error("%s died strangely", hook_name);
100         default:
101                 error("%s exited with error code %d", hook_name, -code);
102                 return -code;
103         }
104 }
105
106 static int run_hook(const char *hook_name)
107 {
108         static char buf[sizeof(commands->old_sha1) * 2 + PATH_MAX + 4];
109         struct command *cmd;
110         struct child_process proc;
111         const char *argv[2];
112         int have_input = 0, code;
113
114         for (cmd = commands; !have_input && cmd; cmd = cmd->next) {
115                 if (!cmd->error_string)
116                         have_input = 1;
117         }
118
119         if (!have_input || access(hook_name, X_OK) < 0)
120                 return 0;
121
122         argv[0] = hook_name;
123         argv[1] = NULL;
124
125         memset(&proc, 0, sizeof(proc));
126         proc.argv = argv;
127         proc.in = -1;
128         proc.stdout_to_stderr = 1;
129
130         code = start_command(&proc);
131         if (code)
132                 return hook_status(code, hook_name);
133         for (cmd = commands; cmd; cmd = cmd->next) {
134                 if (!cmd->error_string) {
135                         size_t n = snprintf(buf, sizeof(buf), "%s %s %s\n",
136                                 sha1_to_hex(cmd->old_sha1),
137                                 sha1_to_hex(cmd->new_sha1),
138                                 cmd->ref_name);
139                         if (write_in_full(proc.in, buf, n) != n)
140                                 break;
141                 }
142         }
143         close(proc.in);
144         return hook_status(finish_command(&proc), hook_name);
145 }
146
147 static int run_update_hook(struct command *cmd)
148 {
149         static const char update_hook[] = "hooks/update";
150         struct child_process proc;
151         const char *argv[5];
152
153         if (access(update_hook, X_OK) < 0)
154                 return 0;
155
156         argv[0] = update_hook;
157         argv[1] = cmd->ref_name;
158         argv[2] = sha1_to_hex(cmd->old_sha1);
159         argv[3] = sha1_to_hex(cmd->new_sha1);
160         argv[4] = NULL;
161
162         memset(&proc, 0, sizeof(proc));
163         proc.argv = argv;
164         proc.no_stdin = 1;
165         proc.stdout_to_stderr = 1;
166
167         return hook_status(run_command(&proc), update_hook);
168 }
169
170 static const char *update(struct command *cmd)
171 {
172         const char *name = cmd->ref_name;
173         unsigned char *old_sha1 = cmd->old_sha1;
174         unsigned char *new_sha1 = cmd->new_sha1;
175         struct ref_lock *lock;
176
177         /* only refs/... are allowed */
178         if (prefixcmp(name, "refs/") || check_ref_format(name + 5)) {
179                 error("refusing to create funny ref '%s' remotely", name);
180                 return "funny refname";
181         }
182
183         if (!is_null_sha1(new_sha1) && !has_sha1_file(new_sha1)) {
184                 error("unpack should have generated %s, "
185                       "but I can't find it!", sha1_to_hex(new_sha1));
186                 return "bad pack";
187         }
188         if (deny_non_fast_forwards && !is_null_sha1(new_sha1) &&
189             !is_null_sha1(old_sha1) &&
190             !prefixcmp(name, "refs/heads/")) {
191                 struct object *old_object, *new_object;
192                 struct commit *old_commit, *new_commit;
193                 struct commit_list *bases, *ent;
194
195                 old_object = parse_object(old_sha1);
196                 new_object = parse_object(new_sha1);
197
198                 if (!old_object || !new_object ||
199                     old_object->type != OBJ_COMMIT ||
200                     new_object->type != OBJ_COMMIT) {
201                         error("bad sha1 objects for %s", name);
202                         return "bad ref";
203                 }
204                 old_commit = (struct commit *)old_object;
205                 new_commit = (struct commit *)new_object;
206                 bases = get_merge_bases(old_commit, new_commit, 1);
207                 for (ent = bases; ent; ent = ent->next)
208                         if (!hashcmp(old_sha1, ent->item->object.sha1))
209                                 break;
210                 free_commit_list(bases);
211                 if (!ent) {
212                         error("denying non-fast forward %s"
213                               " (you should pull first)", name);
214                         return "non-fast forward";
215                 }
216         }
217         if (run_update_hook(cmd)) {
218                 error("hook declined to update %s", name);
219                 return "hook declined";
220         }
221
222         if (is_null_sha1(new_sha1)) {
223                 if (!parse_object(old_sha1)) {
224                         warning ("Allowing deletion of corrupt ref.");
225                         old_sha1 = NULL;
226                 }
227                 if (delete_ref(name, old_sha1)) {
228                         error("failed to delete %s", name);
229                         return "failed to delete";
230                 }
231                 return NULL; /* good */
232         }
233         else {
234                 lock = lock_any_ref_for_update(name, old_sha1, 0);
235                 if (!lock) {
236                         error("failed to lock %s", name);
237                         return "failed to lock";
238                 }
239                 if (write_ref_sha1(lock, new_sha1, "push")) {
240                         return "failed to write"; /* error() already called */
241                 }
242                 return NULL; /* good */
243         }
244 }
245
246 static char update_post_hook[] = "hooks/post-update";
247
248 static void run_update_post_hook(struct command *cmd)
249 {
250         struct command *cmd_p;
251         int argc;
252         const char **argv;
253
254         for (argc = 0, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
255                 if (cmd_p->error_string)
256                         continue;
257                 argc++;
258         }
259         if (!argc || access(update_post_hook, X_OK) < 0)
260                 return;
261         argv = xmalloc(sizeof(*argv) * (2 + argc));
262         argv[0] = update_post_hook;
263
264         for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
265                 char *p;
266                 if (cmd_p->error_string)
267                         continue;
268                 p = xmalloc(strlen(cmd_p->ref_name) + 1);
269                 strcpy(p, cmd_p->ref_name);
270                 argv[argc] = p;
271                 argc++;
272         }
273         argv[argc] = NULL;
274         run_command_v_opt(argv, RUN_COMMAND_NO_STDIN
275                 | RUN_COMMAND_STDOUT_TO_STDERR);
276 }
277
278 static void execute_commands(const char *unpacker_error)
279 {
280         struct command *cmd = commands;
281
282         if (unpacker_error) {
283                 while (cmd) {
284                         cmd->error_string = "n/a (unpacker error)";
285                         cmd = cmd->next;
286                 }
287                 return;
288         }
289
290         if (run_hook(pre_receive_hook)) {
291                 while (cmd) {
292                         cmd->error_string = "pre-receive hook declined";
293                         cmd = cmd->next;
294                 }
295                 return;
296         }
297
298         while (cmd) {
299                 cmd->error_string = update(cmd);
300                 cmd = cmd->next;
301         }
302 }
303
304 static void read_head_info(void)
305 {
306         struct command **p = &commands;
307         for (;;) {
308                 static char line[1000];
309                 unsigned char old_sha1[20], new_sha1[20];
310                 struct command *cmd;
311                 char *refname;
312                 int len, reflen;
313
314                 len = packet_read_line(0, line, sizeof(line));
315                 if (!len)
316                         break;
317                 if (line[len-1] == '\n')
318                         line[--len] = 0;
319                 if (len < 83 ||
320                     line[40] != ' ' ||
321                     line[81] != ' ' ||
322                     get_sha1_hex(line, old_sha1) ||
323                     get_sha1_hex(line + 41, new_sha1))
324                         die("protocol error: expected old/new/ref, got '%s'",
325                             line);
326
327                 refname = line + 82;
328                 reflen = strlen(refname);
329                 if (reflen + 82 < len) {
330                         if (strstr(refname + reflen + 1, "report-status"))
331                                 report_status = 1;
332                 }
333                 cmd = xmalloc(sizeof(struct command) + len - 80);
334                 hashcpy(cmd->old_sha1, old_sha1);
335                 hashcpy(cmd->new_sha1, new_sha1);
336                 memcpy(cmd->ref_name, line + 82, len - 81);
337                 cmd->error_string = NULL;
338                 cmd->next = NULL;
339                 *p = cmd;
340                 p = &cmd->next;
341         }
342 }
343
344 static const char *parse_pack_header(struct pack_header *hdr)
345 {
346         switch (read_pack_header(0, hdr)) {
347         case PH_ERROR_EOF:
348                 return "eof before pack header was fully read";
349
350         case PH_ERROR_PACK_SIGNATURE:
351                 return "protocol error (pack signature mismatch detected)";
352
353         case PH_ERROR_PROTOCOL:
354                 return "protocol error (pack version unsupported)";
355
356         default:
357                 return "unknown error in parse_pack_header";
358
359         case 0:
360                 return NULL;
361         }
362 }
363
364 static const char *pack_lockfile;
365
366 static const char *unpack(void)
367 {
368         struct pack_header hdr;
369         const char *hdr_err;
370         char hdr_arg[38];
371
372         hdr_err = parse_pack_header(&hdr);
373         if (hdr_err)
374                 return hdr_err;
375         snprintf(hdr_arg, sizeof(hdr_arg),
376                         "--pack_header=%"PRIu32",%"PRIu32,
377                         ntohl(hdr.hdr_version), ntohl(hdr.hdr_entries));
378
379         if (ntohl(hdr.hdr_entries) < unpack_limit) {
380                 int code, i = 0;
381                 const char *unpacker[4];
382                 unpacker[i++] = "unpack-objects";
383                 if (receive_fsck_objects)
384                         unpacker[i++] = "--strict";
385                 unpacker[i++] = hdr_arg;
386                 unpacker[i++] = NULL;
387                 code = run_command_v_opt(unpacker, RUN_GIT_CMD);
388                 switch (code) {
389                 case 0:
390                         return NULL;
391                 case -ERR_RUN_COMMAND_FORK:
392                         return "unpack fork failed";
393                 case -ERR_RUN_COMMAND_EXEC:
394                         return "unpack execute failed";
395                 case -ERR_RUN_COMMAND_WAITPID:
396                         return "waitpid failed";
397                 case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
398                         return "waitpid is confused";
399                 case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
400                         return "unpacker died of signal";
401                 case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
402                         return "unpacker died strangely";
403                 default:
404                         return "unpacker exited with error code";
405                 }
406         } else {
407                 const char *keeper[7];
408                 int s, status, i = 0;
409                 char keep_arg[256];
410                 struct child_process ip;
411
412                 s = sprintf(keep_arg, "--keep=receive-pack %"PRIuMAX" on ", (uintmax_t) getpid());
413                 if (gethostname(keep_arg + s, sizeof(keep_arg) - s))
414                         strcpy(keep_arg + s, "localhost");
415
416                 keeper[i++] = "index-pack";
417                 keeper[i++] = "--stdin";
418                 if (receive_fsck_objects)
419                         keeper[i++] = "--strict";
420                 keeper[i++] = "--fix-thin";
421                 keeper[i++] = hdr_arg;
422                 keeper[i++] = keep_arg;
423                 keeper[i++] = NULL;
424                 memset(&ip, 0, sizeof(ip));
425                 ip.argv = keeper;
426                 ip.out = -1;
427                 ip.git_cmd = 1;
428                 if (start_command(&ip))
429                         return "index-pack fork failed";
430                 pack_lockfile = index_pack_lockfile(ip.out);
431                 close(ip.out);
432                 status = finish_command(&ip);
433                 if (!status) {
434                         reprepare_packed_git();
435                         return NULL;
436                 }
437                 return "index-pack abnormal exit";
438         }
439 }
440
441 static void report(const char *unpack_status)
442 {
443         struct command *cmd;
444         packet_write(1, "unpack %s\n",
445                      unpack_status ? unpack_status : "ok");
446         for (cmd = commands; cmd; cmd = cmd->next) {
447                 if (!cmd->error_string)
448                         packet_write(1, "ok %s\n",
449                                      cmd->ref_name);
450                 else
451                         packet_write(1, "ng %s %s\n",
452                                      cmd->ref_name, cmd->error_string);
453         }
454         packet_flush(1);
455 }
456
457 static int delete_only(struct command *cmd)
458 {
459         while (cmd) {
460                 if (!is_null_sha1(cmd->new_sha1))
461                         return 0;
462                 cmd = cmd->next;
463         }
464         return 1;
465 }
466
467 static int add_refs_from_alternate(struct alternate_object_database *e, void *unused)
468 {
469         char *other = xstrdup(make_absolute_path(e->base));
470         size_t len = strlen(other);
471         struct remote *remote;
472         struct transport *transport;
473         const struct ref *extra;
474
475         while (other[len-1] == '/')
476                 other[--len] = '\0';
477         if (len < 8 || memcmp(other + len - 8, "/objects", 8))
478                 return 0;
479         /* Is this a git repository with refs? */
480         memcpy(other + len - 8, "/refs", 6);
481         if (!is_directory(other))
482                 return 0;
483         other[len - 8] = '\0';
484         remote = remote_get(other);
485         transport = transport_get(remote, other);
486         for (extra = transport_get_remote_refs(transport);
487              extra;
488              extra = extra->next) {
489                 add_extra_ref(".have", extra->old_sha1, 0);
490         }
491         transport_disconnect(transport);
492         free(other);
493         return 0;
494 }
495
496 static void add_alternate_refs(void)
497 {
498         foreach_alt_odb(add_refs_from_alternate, NULL);
499 }
500
501 int cmd_receive_pack(int argc, const char **argv, const char *prefix)
502 {
503         int i;
504         char *dir = NULL;
505
506         argv++;
507         for (i = 1; i < argc; i++) {
508                 const char *arg = *argv++;
509
510                 if (*arg == '-') {
511                         /* Do flag handling here */
512                         usage(receive_pack_usage);
513                 }
514                 if (dir)
515                         usage(receive_pack_usage);
516                 dir = xstrdup(arg);
517         }
518         if (!dir)
519                 usage(receive_pack_usage);
520
521         setup_path();
522
523         if (!enter_repo(dir, 0))
524                 die("'%s': unable to chdir or not a git archive", dir);
525
526         if (is_repository_shallow())
527                 die("attempt to push into a shallow repository");
528
529         git_config(receive_pack_config, NULL);
530
531         if (0 <= transfer_unpack_limit)
532                 unpack_limit = transfer_unpack_limit;
533         else if (0 <= receive_unpack_limit)
534                 unpack_limit = receive_unpack_limit;
535
536         add_alternate_refs();
537         write_head_info();
538         clear_extra_refs();
539
540         /* EOF */
541         packet_flush(1);
542
543         read_head_info();
544         if (commands) {
545                 const char *unpack_status = NULL;
546
547                 if (!delete_only(commands))
548                         unpack_status = unpack();
549                 execute_commands(unpack_status);
550                 if (pack_lockfile)
551                         unlink(pack_lockfile);
552                 if (report_status)
553                         report(unpack_status);
554                 run_hook(post_receive_hook);
555                 run_update_post_hook(commands);
556         }
557         return 0;
558 }