fsck: exit with non-zero status upon errors
[git] / 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
10 static const char receive_pack_usage[] = "git-receive-pack <git-dir>";
11
12 static int deny_non_fast_forwards = 0;
13 static int receive_unpack_limit = -1;
14 static int transfer_unpack_limit = -1;
15 static int unpack_limit = 100;
16 static int report_status;
17
18 static char capabilities[] = " report-status delete-refs ";
19 static int capabilities_sent;
20
21 static int receive_pack_config(const char *var, const char *value)
22 {
23         if (strcmp(var, "receive.denynonfastforwards") == 0) {
24                 deny_non_fast_forwards = git_config_bool(var, value);
25                 return 0;
26         }
27
28         if (strcmp(var, "receive.unpacklimit") == 0) {
29                 receive_unpack_limit = git_config_int(var, value);
30                 return 0;
31         }
32
33         if (strcmp(var, "transfer.unpacklimit") == 0) {
34                 transfer_unpack_limit = git_config_int(var, value);
35                 return 0;
36         }
37
38         return git_default_config(var, value);
39 }
40
41 static int show_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
42 {
43         if (capabilities_sent)
44                 packet_write(1, "%s %s\n", sha1_to_hex(sha1), path);
45         else
46                 packet_write(1, "%s %s%c%s\n",
47                              sha1_to_hex(sha1), path, 0, capabilities);
48         capabilities_sent = 1;
49         return 0;
50 }
51
52 static void write_head_info(void)
53 {
54         for_each_ref(show_ref, NULL);
55         if (!capabilities_sent)
56                 show_ref("capabilities^{}", null_sha1, 0, NULL);
57
58 }
59
60 struct command {
61         struct command *next;
62         const char *error_string;
63         unsigned char old_sha1[20];
64         unsigned char new_sha1[20];
65         char ref_name[FLEX_ARRAY]; /* more */
66 };
67
68 static struct command *commands;
69
70 static char update_hook[] = "hooks/update";
71
72 static int run_update_hook(const char *refname,
73                            char *old_hex, char *new_hex)
74 {
75         int code;
76
77         if (access(update_hook, X_OK) < 0)
78                 return 0;
79         code = run_command_opt(RUN_COMMAND_NO_STDIN
80                 | RUN_COMMAND_STDOUT_TO_STDERR,
81                 update_hook, refname, old_hex, new_hex, NULL);
82         switch (code) {
83         case 0:
84                 return 0;
85         case -ERR_RUN_COMMAND_FORK:
86                 return error("hook fork failed");
87         case -ERR_RUN_COMMAND_EXEC:
88                 return error("hook execute failed");
89         case -ERR_RUN_COMMAND_WAITPID:
90                 return error("waitpid failed");
91         case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
92                 return error("waitpid is confused");
93         case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
94                 return error("%s died of signal", update_hook);
95         case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
96                 return error("%s died strangely", update_hook);
97         default:
98                 error("%s exited with error code %d", update_hook, -code);
99                 return -code;
100         }
101 }
102
103 static int update(struct command *cmd)
104 {
105         const char *name = cmd->ref_name;
106         unsigned char *old_sha1 = cmd->old_sha1;
107         unsigned char *new_sha1 = cmd->new_sha1;
108         char new_hex[41], old_hex[41];
109         struct ref_lock *lock;
110
111         cmd->error_string = NULL;
112         if (!prefixcmp(name, "refs/") && check_ref_format(name + 5)) {
113                 cmd->error_string = "funny refname";
114                 return error("refusing to create funny ref '%s' locally",
115                              name);
116         }
117
118         strcpy(new_hex, sha1_to_hex(new_sha1));
119         strcpy(old_hex, sha1_to_hex(old_sha1));
120
121         if (!is_null_sha1(new_sha1) && !has_sha1_file(new_sha1)) {
122                 cmd->error_string = "bad pack";
123                 return error("unpack should have generated %s, "
124                              "but I can't find it!", new_hex);
125         }
126         if (deny_non_fast_forwards && !is_null_sha1(new_sha1) &&
127             !is_null_sha1(old_sha1) &&
128             !prefixcmp(name, "refs/heads/")) {
129                 struct commit *old_commit, *new_commit;
130                 struct commit_list *bases, *ent;
131
132                 old_commit = (struct commit *)parse_object(old_sha1);
133                 new_commit = (struct commit *)parse_object(new_sha1);
134                 bases = get_merge_bases(old_commit, new_commit, 1);
135                 for (ent = bases; ent; ent = ent->next)
136                         if (!hashcmp(old_sha1, ent->item->object.sha1))
137                                 break;
138                 free_commit_list(bases);
139                 if (!ent)
140                         return error("denying non-fast forward;"
141                                      " you should pull first");
142         }
143         if (run_update_hook(name, old_hex, new_hex)) {
144                 cmd->error_string = "hook declined";
145                 return error("hook declined to update %s", name);
146         }
147
148         if (is_null_sha1(new_sha1)) {
149                 if (delete_ref(name, old_sha1)) {
150                         cmd->error_string = "failed to delete";
151                         return error("failed to delete %s", name);
152                 }
153                 fprintf(stderr, "%s: %s -> deleted\n", name, old_hex);
154         }
155         else {
156                 lock = lock_any_ref_for_update(name, old_sha1);
157                 if (!lock) {
158                         cmd->error_string = "failed to lock";
159                         return error("failed to lock %s", name);
160                 }
161                 write_ref_sha1(lock, new_sha1, "push");
162                 fprintf(stderr, "%s: %s -> %s\n", name, old_hex, new_hex);
163         }
164         return 0;
165 }
166
167 static char update_post_hook[] = "hooks/post-update";
168
169 static void run_update_post_hook(struct command *cmd)
170 {
171         struct command *cmd_p;
172         int argc;
173         const char **argv;
174
175         if (access(update_post_hook, X_OK) < 0)
176                 return;
177         for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
178                 if (cmd_p->error_string)
179                         continue;
180                 argc++;
181         }
182         argv = xmalloc(sizeof(*argv) * (1 + argc));
183         argv[0] = update_post_hook;
184
185         for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
186                 char *p;
187                 if (cmd_p->error_string)
188                         continue;
189                 p = xmalloc(strlen(cmd_p->ref_name) + 1);
190                 strcpy(p, cmd_p->ref_name);
191                 argv[argc] = p;
192                 argc++;
193         }
194         argv[argc] = NULL;
195         run_command_v_opt(argv, RUN_COMMAND_NO_STDIN
196                 | RUN_COMMAND_STDOUT_TO_STDERR);
197 }
198
199 /*
200  * This gets called after(if) we've successfully
201  * unpacked the data payload.
202  */
203 static void execute_commands(void)
204 {
205         struct command *cmd = commands;
206
207         while (cmd) {
208                 update(cmd);
209                 cmd = cmd->next;
210         }
211         run_update_post_hook(commands);
212 }
213
214 static void read_head_info(void)
215 {
216         struct command **p = &commands;
217         for (;;) {
218                 static char line[1000];
219                 unsigned char old_sha1[20], new_sha1[20];
220                 struct command *cmd;
221                 char *refname;
222                 int len, reflen;
223
224                 len = packet_read_line(0, line, sizeof(line));
225                 if (!len)
226                         break;
227                 if (line[len-1] == '\n')
228                         line[--len] = 0;
229                 if (len < 83 ||
230                     line[40] != ' ' ||
231                     line[81] != ' ' ||
232                     get_sha1_hex(line, old_sha1) ||
233                     get_sha1_hex(line + 41, new_sha1))
234                         die("protocol error: expected old/new/ref, got '%s'",
235                             line);
236
237                 refname = line + 82;
238                 reflen = strlen(refname);
239                 if (reflen + 82 < len) {
240                         if (strstr(refname + reflen + 1, "report-status"))
241                                 report_status = 1;
242                 }
243                 cmd = xmalloc(sizeof(struct command) + len - 80);
244                 hashcpy(cmd->old_sha1, old_sha1);
245                 hashcpy(cmd->new_sha1, new_sha1);
246                 memcpy(cmd->ref_name, line + 82, len - 81);
247                 cmd->error_string = "n/a (unpacker error)";
248                 cmd->next = NULL;
249                 *p = cmd;
250                 p = &cmd->next;
251         }
252 }
253
254 static const char *parse_pack_header(struct pack_header *hdr)
255 {
256         switch (read_pack_header(0, hdr)) {
257         case PH_ERROR_EOF:
258                 return "eof before pack header was fully read";
259
260         case PH_ERROR_PACK_SIGNATURE:
261                 return "protocol error (pack signature mismatch detected)";
262
263         case PH_ERROR_PROTOCOL:
264                 return "protocol error (pack version unsupported)";
265
266         default:
267                 return "unknown error in parse_pack_header";
268
269         case 0:
270                 return NULL;
271         }
272 }
273
274 static const char *pack_lockfile;
275
276 static const char *unpack(void)
277 {
278         struct pack_header hdr;
279         const char *hdr_err;
280         char hdr_arg[38];
281
282         hdr_err = parse_pack_header(&hdr);
283         if (hdr_err)
284                 return hdr_err;
285         snprintf(hdr_arg, sizeof(hdr_arg), "--pack_header=%u,%u",
286                         ntohl(hdr.hdr_version), ntohl(hdr.hdr_entries));
287
288         if (ntohl(hdr.hdr_entries) < unpack_limit) {
289                 int code;
290                 const char *unpacker[3];
291                 unpacker[0] = "unpack-objects";
292                 unpacker[1] = hdr_arg;
293                 unpacker[2] = NULL;
294                 code = run_command_v_opt(unpacker, RUN_GIT_CMD);
295                 switch (code) {
296                 case 0:
297                         return NULL;
298                 case -ERR_RUN_COMMAND_FORK:
299                         return "unpack fork failed";
300                 case -ERR_RUN_COMMAND_EXEC:
301                         return "unpack execute failed";
302                 case -ERR_RUN_COMMAND_WAITPID:
303                         return "waitpid failed";
304                 case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
305                         return "waitpid is confused";
306                 case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
307                         return "unpacker died of signal";
308                 case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
309                         return "unpacker died strangely";
310                 default:
311                         return "unpacker exited with error code";
312                 }
313         } else {
314                 const char *keeper[6];
315                 int fd[2], s, len, status;
316                 pid_t pid;
317                 char keep_arg[256];
318                 char packname[46];
319
320                 s = sprintf(keep_arg, "--keep=receive-pack %i on ", getpid());
321                 if (gethostname(keep_arg + s, sizeof(keep_arg) - s))
322                         strcpy(keep_arg + s, "localhost");
323
324                 keeper[0] = "index-pack";
325                 keeper[1] = "--stdin";
326                 keeper[2] = "--fix-thin";
327                 keeper[3] = hdr_arg;
328                 keeper[4] = keep_arg;
329                 keeper[5] = NULL;
330
331                 if (pipe(fd) < 0)
332                         return "index-pack pipe failed";
333                 pid = fork();
334                 if (pid < 0)
335                         return "index-pack fork failed";
336                 if (!pid) {
337                         dup2(fd[1], 1);
338                         close(fd[1]);
339                         close(fd[0]);
340                         execv_git_cmd(keeper);
341                         die("execv of index-pack failed");
342                 }
343                 close(fd[1]);
344
345                 /*
346                  * The first thing we expects from index-pack's output
347                  * is "pack\t%40s\n" or "keep\t%40s\n" (46 bytes) where
348                  * %40s is the newly created pack SHA1 name.  In the "keep"
349                  * case, we need it to remove the corresponding .keep file
350                  * later on.  If we don't get that then tough luck with it.
351                  */
352                 for (len = 0;
353                      len < 46 && (s = xread(fd[0], packname+len, 46-len)) > 0;
354                      len += s);
355                 close(fd[0]);
356                 if (len == 46 && packname[45] == '\n' &&
357                     memcmp(packname, "keep\t", 5) == 0) {
358                         char path[PATH_MAX];
359                         packname[45] = 0;
360                         snprintf(path, sizeof(path), "%s/pack/pack-%s.keep",
361                                  get_object_directory(), packname + 5);
362                         pack_lockfile = xstrdup(path);
363                 }
364
365                 /* Then wrap our index-pack process. */
366                 while (waitpid(pid, &status, 0) < 0)
367                         if (errno != EINTR)
368                                 return "waitpid failed";
369                 if (WIFEXITED(status)) {
370                         int code = WEXITSTATUS(status);
371                         if (code)
372                                 return "index-pack exited with error code";
373                         reprepare_packed_git();
374                         return NULL;
375                 }
376                 return "index-pack abnormal exit";
377         }
378 }
379
380 static void report(const char *unpack_status)
381 {
382         struct command *cmd;
383         packet_write(1, "unpack %s\n",
384                      unpack_status ? unpack_status : "ok");
385         for (cmd = commands; cmd; cmd = cmd->next) {
386                 if (!cmd->error_string)
387                         packet_write(1, "ok %s\n",
388                                      cmd->ref_name);
389                 else
390                         packet_write(1, "ng %s %s\n",
391                                      cmd->ref_name, cmd->error_string);
392         }
393         packet_flush(1);
394 }
395
396 static int delete_only(struct command *cmd)
397 {
398         while (cmd) {
399                 if (!is_null_sha1(cmd->new_sha1))
400                         return 0;
401                 cmd = cmd->next;
402         }
403         return 1;
404 }
405
406 int main(int argc, char **argv)
407 {
408         int i;
409         char *dir = NULL;
410
411         argv++;
412         for (i = 1; i < argc; i++) {
413                 char *arg = *argv++;
414
415                 if (*arg == '-') {
416                         /* Do flag handling here */
417                         usage(receive_pack_usage);
418                 }
419                 if (dir)
420                         usage(receive_pack_usage);
421                 dir = arg;
422         }
423         if (!dir)
424                 usage(receive_pack_usage);
425
426         if (!enter_repo(dir, 0))
427                 die("'%s': unable to chdir or not a git archive", dir);
428
429         if (is_repository_shallow())
430                 die("attempt to push into a shallow repository");
431
432         git_config(receive_pack_config);
433
434         if (0 <= transfer_unpack_limit)
435                 unpack_limit = transfer_unpack_limit;
436         else if (0 <= receive_unpack_limit)
437                 unpack_limit = receive_unpack_limit;
438
439         write_head_info();
440
441         /* EOF */
442         packet_flush(1);
443
444         read_head_info();
445         if (commands) {
446                 const char *unpack_status = NULL;
447
448                 if (!delete_only(commands))
449                         unpack_status = unpack();
450                 if (!unpack_status)
451                         execute_commands();
452                 if (pack_lockfile)
453                         unlink(pack_lockfile);
454                 if (report_status)
455                         report(unpack_status);
456         }
457         return 0;
458 }