Simplify fetch transport API to just one function
[git/git.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 const char pre_receive_hook[] = "hooks/pre-receive";
71 static const char post_receive_hook[] = "hooks/post-receive";
72
73 static int hook_status(int code, const char *hook_name)
74 {
75 switch (code) {
76 case 0:
77 return 0;
78 case -ERR_RUN_COMMAND_FORK:
79 return error("hook fork failed");
80 case -ERR_RUN_COMMAND_EXEC:
81 return error("hook execute failed");
82 case -ERR_RUN_COMMAND_PIPE:
83 return error("hook pipe failed");
84 case -ERR_RUN_COMMAND_WAITPID:
85 return error("waitpid failed");
86 case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
87 return error("waitpid is confused");
88 case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
89 return error("%s died of signal", hook_name);
90 case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
91 return error("%s died strangely", hook_name);
92 default:
93 error("%s exited with error code %d", hook_name, -code);
94 return -code;
95 }
96 }
97
98 static int run_hook(const char *hook_name)
99 {
100 static char buf[sizeof(commands->old_sha1) * 2 + PATH_MAX + 4];
101 struct command *cmd;
102 struct child_process proc;
103 const char *argv[2];
104 int have_input = 0, code;
105
106 for (cmd = commands; !have_input && cmd; cmd = cmd->next) {
107 if (!cmd->error_string)
108 have_input = 1;
109 }
110
111 if (!have_input || access(hook_name, X_OK) < 0)
112 return 0;
113
114 argv[0] = hook_name;
115 argv[1] = NULL;
116
117 memset(&proc, 0, sizeof(proc));
118 proc.argv = argv;
119 proc.in = -1;
120 proc.stdout_to_stderr = 1;
121
122 code = start_command(&proc);
123 if (code)
124 return hook_status(code, hook_name);
125 for (cmd = commands; cmd; cmd = cmd->next) {
126 if (!cmd->error_string) {
127 size_t n = snprintf(buf, sizeof(buf), "%s %s %s\n",
128 sha1_to_hex(cmd->old_sha1),
129 sha1_to_hex(cmd->new_sha1),
130 cmd->ref_name);
131 if (write_in_full(proc.in, buf, n) != n)
132 break;
133 }
134 }
135 return hook_status(finish_command(&proc), hook_name);
136 }
137
138 static int run_update_hook(struct command *cmd)
139 {
140 static const char update_hook[] = "hooks/update";
141 struct child_process proc;
142 const char *argv[5];
143
144 if (access(update_hook, X_OK) < 0)
145 return 0;
146
147 argv[0] = update_hook;
148 argv[1] = cmd->ref_name;
149 argv[2] = sha1_to_hex(cmd->old_sha1);
150 argv[3] = sha1_to_hex(cmd->new_sha1);
151 argv[4] = NULL;
152
153 memset(&proc, 0, sizeof(proc));
154 proc.argv = argv;
155 proc.no_stdin = 1;
156 proc.stdout_to_stderr = 1;
157
158 return hook_status(run_command(&proc), update_hook);
159 }
160
161 static const char *update(struct command *cmd)
162 {
163 const char *name = cmd->ref_name;
164 unsigned char *old_sha1 = cmd->old_sha1;
165 unsigned char *new_sha1 = cmd->new_sha1;
166 struct ref_lock *lock;
167
168 if (!prefixcmp(name, "refs/") && check_ref_format(name + 5)) {
169 error("refusing to create funny ref '%s' locally", name);
170 return "funny refname";
171 }
172
173 if (!is_null_sha1(new_sha1) && !has_sha1_file(new_sha1)) {
174 error("unpack should have generated %s, "
175 "but I can't find it!", sha1_to_hex(new_sha1));
176 return "bad pack";
177 }
178 if (deny_non_fast_forwards && !is_null_sha1(new_sha1) &&
179 !is_null_sha1(old_sha1) &&
180 !prefixcmp(name, "refs/heads/")) {
181 struct commit *old_commit, *new_commit;
182 struct commit_list *bases, *ent;
183
184 old_commit = (struct commit *)parse_object(old_sha1);
185 new_commit = (struct commit *)parse_object(new_sha1);
186 bases = get_merge_bases(old_commit, new_commit, 1);
187 for (ent = bases; ent; ent = ent->next)
188 if (!hashcmp(old_sha1, ent->item->object.sha1))
189 break;
190 free_commit_list(bases);
191 if (!ent) {
192 error("denying non-fast forward %s"
193 " (you should pull first)", name);
194 return "non-fast forward";
195 }
196 }
197 if (run_update_hook(cmd)) {
198 error("hook declined to update %s", name);
199 return "hook declined";
200 }
201
202 if (is_null_sha1(new_sha1)) {
203 if (delete_ref(name, old_sha1)) {
204 error("failed to delete %s", name);
205 return "failed to delete";
206 }
207 fprintf(stderr, "%s: %s -> deleted\n", name,
208 sha1_to_hex(old_sha1));
209 return NULL; /* good */
210 }
211 else {
212 lock = lock_any_ref_for_update(name, old_sha1, 0);
213 if (!lock) {
214 error("failed to lock %s", name);
215 return "failed to lock";
216 }
217 if (write_ref_sha1(lock, new_sha1, "push")) {
218 return "failed to write"; /* error() already called */
219 }
220 fprintf(stderr, "%s: %s -> %s\n", name,
221 sha1_to_hex(old_sha1), sha1_to_hex(new_sha1));
222 return NULL; /* good */
223 }
224 }
225
226 static char update_post_hook[] = "hooks/post-update";
227
228 static void run_update_post_hook(struct command *cmd)
229 {
230 struct command *cmd_p;
231 int argc;
232 const char **argv;
233
234 for (argc = 0, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
235 if (cmd_p->error_string)
236 continue;
237 argc++;
238 }
239 if (!argc || access(update_post_hook, X_OK) < 0)
240 return;
241 argv = xmalloc(sizeof(*argv) * (2 + argc));
242 argv[0] = update_post_hook;
243
244 for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
245 char *p;
246 if (cmd_p->error_string)
247 continue;
248 p = xmalloc(strlen(cmd_p->ref_name) + 1);
249 strcpy(p, cmd_p->ref_name);
250 argv[argc] = p;
251 argc++;
252 }
253 argv[argc] = NULL;
254 run_command_v_opt(argv, RUN_COMMAND_NO_STDIN
255 | RUN_COMMAND_STDOUT_TO_STDERR);
256 }
257
258 static void execute_commands(const char *unpacker_error)
259 {
260 struct command *cmd = commands;
261
262 if (unpacker_error) {
263 while (cmd) {
264 cmd->error_string = "n/a (unpacker error)";
265 cmd = cmd->next;
266 }
267 return;
268 }
269
270 if (run_hook(pre_receive_hook)) {
271 while (cmd) {
272 cmd->error_string = "pre-receive hook declined";
273 cmd = cmd->next;
274 }
275 return;
276 }
277
278 while (cmd) {
279 cmd->error_string = update(cmd);
280 cmd = cmd->next;
281 }
282 }
283
284 static void read_head_info(void)
285 {
286 struct command **p = &commands;
287 for (;;) {
288 static char line[1000];
289 unsigned char old_sha1[20], new_sha1[20];
290 struct command *cmd;
291 char *refname;
292 int len, reflen;
293
294 len = packet_read_line(0, line, sizeof(line));
295 if (!len)
296 break;
297 if (line[len-1] == '\n')
298 line[--len] = 0;
299 if (len < 83 ||
300 line[40] != ' ' ||
301 line[81] != ' ' ||
302 get_sha1_hex(line, old_sha1) ||
303 get_sha1_hex(line + 41, new_sha1))
304 die("protocol error: expected old/new/ref, got '%s'",
305 line);
306
307 refname = line + 82;
308 reflen = strlen(refname);
309 if (reflen + 82 < len) {
310 if (strstr(refname + reflen + 1, "report-status"))
311 report_status = 1;
312 }
313 cmd = xmalloc(sizeof(struct command) + len - 80);
314 hashcpy(cmd->old_sha1, old_sha1);
315 hashcpy(cmd->new_sha1, new_sha1);
316 memcpy(cmd->ref_name, line + 82, len - 81);
317 cmd->error_string = NULL;
318 cmd->next = NULL;
319 *p = cmd;
320 p = &cmd->next;
321 }
322 }
323
324 static const char *parse_pack_header(struct pack_header *hdr)
325 {
326 switch (read_pack_header(0, hdr)) {
327 case PH_ERROR_EOF:
328 return "eof before pack header was fully read";
329
330 case PH_ERROR_PACK_SIGNATURE:
331 return "protocol error (pack signature mismatch detected)";
332
333 case PH_ERROR_PROTOCOL:
334 return "protocol error (pack version unsupported)";
335
336 default:
337 return "unknown error in parse_pack_header";
338
339 case 0:
340 return NULL;
341 }
342 }
343
344 static const char *pack_lockfile;
345
346 static const char *unpack(void)
347 {
348 struct pack_header hdr;
349 const char *hdr_err;
350 char hdr_arg[38];
351
352 hdr_err = parse_pack_header(&hdr);
353 if (hdr_err)
354 return hdr_err;
355 snprintf(hdr_arg, sizeof(hdr_arg), "--pack_header=%u,%u",
356 ntohl(hdr.hdr_version), ntohl(hdr.hdr_entries));
357
358 if (ntohl(hdr.hdr_entries) < unpack_limit) {
359 int code;
360 const char *unpacker[3];
361 unpacker[0] = "unpack-objects";
362 unpacker[1] = hdr_arg;
363 unpacker[2] = NULL;
364 code = run_command_v_opt(unpacker, RUN_GIT_CMD);
365 switch (code) {
366 case 0:
367 return NULL;
368 case -ERR_RUN_COMMAND_FORK:
369 return "unpack fork failed";
370 case -ERR_RUN_COMMAND_EXEC:
371 return "unpack execute failed";
372 case -ERR_RUN_COMMAND_WAITPID:
373 return "waitpid failed";
374 case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
375 return "waitpid is confused";
376 case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
377 return "unpacker died of signal";
378 case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
379 return "unpacker died strangely";
380 default:
381 return "unpacker exited with error code";
382 }
383 } else {
384 const char *keeper[6];
385 int s, len, status;
386 char keep_arg[256];
387 char packname[46];
388 struct child_process ip;
389
390 s = sprintf(keep_arg, "--keep=receive-pack %i on ", getpid());
391 if (gethostname(keep_arg + s, sizeof(keep_arg) - s))
392 strcpy(keep_arg + s, "localhost");
393
394 keeper[0] = "index-pack";
395 keeper[1] = "--stdin";
396 keeper[2] = "--fix-thin";
397 keeper[3] = hdr_arg;
398 keeper[4] = keep_arg;
399 keeper[5] = NULL;
400 memset(&ip, 0, sizeof(ip));
401 ip.argv = keeper;
402 ip.out = -1;
403 ip.git_cmd = 1;
404 if (start_command(&ip))
405 return "index-pack fork failed";
406
407 /*
408 * The first thing we expects from index-pack's output
409 * is "pack\t%40s\n" or "keep\t%40s\n" (46 bytes) where
410 * %40s is the newly created pack SHA1 name. In the "keep"
411 * case, we need it to remove the corresponding .keep file
412 * later on. If we don't get that then tough luck with it.
413 */
414 for (len = 0;
415 len < 46 && (s = xread(ip.out, packname+len, 46-len)) > 0;
416 len += s);
417 if (len == 46 && packname[45] == '\n' &&
418 memcmp(packname, "keep\t", 5) == 0) {
419 char path[PATH_MAX];
420 packname[45] = 0;
421 snprintf(path, sizeof(path), "%s/pack/pack-%s.keep",
422 get_object_directory(), packname + 5);
423 pack_lockfile = xstrdup(path);
424 }
425
426 status = finish_command(&ip);
427 if (!status) {
428 reprepare_packed_git();
429 return NULL;
430 }
431 return "index-pack abnormal exit";
432 }
433 }
434
435 static void report(const char *unpack_status)
436 {
437 struct command *cmd;
438 packet_write(1, "unpack %s\n",
439 unpack_status ? unpack_status : "ok");
440 for (cmd = commands; cmd; cmd = cmd->next) {
441 if (!cmd->error_string)
442 packet_write(1, "ok %s\n",
443 cmd->ref_name);
444 else
445 packet_write(1, "ng %s %s\n",
446 cmd->ref_name, cmd->error_string);
447 }
448 packet_flush(1);
449 }
450
451 static int delete_only(struct command *cmd)
452 {
453 while (cmd) {
454 if (!is_null_sha1(cmd->new_sha1))
455 return 0;
456 cmd = cmd->next;
457 }
458 return 1;
459 }
460
461 int main(int argc, char **argv)
462 {
463 int i;
464 char *dir = NULL;
465
466 argv++;
467 for (i = 1; i < argc; i++) {
468 char *arg = *argv++;
469
470 if (*arg == '-') {
471 /* Do flag handling here */
472 usage(receive_pack_usage);
473 }
474 if (dir)
475 usage(receive_pack_usage);
476 dir = arg;
477 }
478 if (!dir)
479 usage(receive_pack_usage);
480
481 if (!enter_repo(dir, 0))
482 die("'%s': unable to chdir or not a git archive", dir);
483
484 if (is_repository_shallow())
485 die("attempt to push into a shallow repository");
486
487 git_config(receive_pack_config);
488
489 if (0 <= transfer_unpack_limit)
490 unpack_limit = transfer_unpack_limit;
491 else if (0 <= receive_unpack_limit)
492 unpack_limit = receive_unpack_limit;
493
494 write_head_info();
495
496 /* EOF */
497 packet_flush(1);
498
499 read_head_info();
500 if (commands) {
501 const char *unpack_status = NULL;
502
503 if (!delete_only(commands))
504 unpack_status = unpack();
505 execute_commands(unpack_status);
506 if (pack_lockfile)
507 unlink(pack_lockfile);
508 if (report_status)
509 report(unpack_status);
510 run_hook(post_receive_hook);
511 run_update_post_hook(commands);
512 }
513 return 0;
514 }