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
10static const char receive_pack_usage[] = "git-receive-pack <git-dir>";
11
12static int deny_non_fast_forwards = 0;
13static int receive_unpack_limit = -1;
14static int transfer_unpack_limit = -1;
15static int unpack_limit = 100;
16static int report_status;
17
18static char capabilities[] = " report-status delete-refs ";
19static int capabilities_sent;
20
21static 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
41static 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
52static 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
60struct 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
68static struct command *commands;
69
70static char update_hook[] = "hooks/update";
71
72static 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
103static 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 (!strncmp(name, "refs/", 5) && 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 !strncmp(name, "refs/heads/", 11)) {
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 if (write_ref_sha1(lock, new_sha1, "push")) {
162 cmd->error_string = "failed to write";
163 return -1; /* error() already called */
164 }
165 fprintf(stderr, "%s: %s -> %s\n", name, old_hex, new_hex);
166 }
167 return 0;
168}
169
170static char update_post_hook[] = "hooks/post-update";
171
172static void run_update_post_hook(struct command *cmd)
173{
174 struct command *cmd_p;
175 int argc;
176 const char **argv;
177
178 if (access(update_post_hook, X_OK) < 0)
179 return;
180 for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
181 if (cmd_p->error_string)
182 continue;
183 argc++;
184 }
185 argv = xmalloc(sizeof(*argv) * (1 + argc));
186 argv[0] = update_post_hook;
187
188 for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
189 char *p;
190 if (cmd_p->error_string)
191 continue;
192 p = xmalloc(strlen(cmd_p->ref_name) + 1);
193 strcpy(p, cmd_p->ref_name);
194 argv[argc] = p;
195 argc++;
196 }
197 argv[argc] = NULL;
198 run_command_v_opt(argv, RUN_COMMAND_NO_STDIN
199 | RUN_COMMAND_STDOUT_TO_STDERR);
200}
201
202/*
203 * This gets called after(if) we've successfully
204 * unpacked the data payload.
205 */
206static void execute_commands(void)
207{
208 struct command *cmd = commands;
209
210 while (cmd) {
211 update(cmd);
212 cmd = cmd->next;
213 }
214 run_update_post_hook(commands);
215}
216
217static void read_head_info(void)
218{
219 struct command **p = &commands;
220 for (;;) {
221 static char line[1000];
222 unsigned char old_sha1[20], new_sha1[20];
223 struct command *cmd;
224 char *refname;
225 int len, reflen;
226
227 len = packet_read_line(0, line, sizeof(line));
228 if (!len)
229 break;
230 if (line[len-1] == '\n')
231 line[--len] = 0;
232 if (len < 83 ||
233 line[40] != ' ' ||
234 line[81] != ' ' ||
235 get_sha1_hex(line, old_sha1) ||
236 get_sha1_hex(line + 41, new_sha1))
237 die("protocol error: expected old/new/ref, got '%s'",
238 line);
239
240 refname = line + 82;
241 reflen = strlen(refname);
242 if (reflen + 82 < len) {
243 if (strstr(refname + reflen + 1, "report-status"))
244 report_status = 1;
245 }
246 cmd = xmalloc(sizeof(struct command) + len - 80);
247 hashcpy(cmd->old_sha1, old_sha1);
248 hashcpy(cmd->new_sha1, new_sha1);
249 memcpy(cmd->ref_name, line + 82, len - 81);
250 cmd->error_string = "n/a (unpacker error)";
251 cmd->next = NULL;
252 *p = cmd;
253 p = &cmd->next;
254 }
255}
256
257static const char *parse_pack_header(struct pack_header *hdr)
258{
259 switch (read_pack_header(0, hdr)) {
260 case PH_ERROR_EOF:
261 return "eof before pack header was fully read";
262
263 case PH_ERROR_PACK_SIGNATURE:
264 return "protocol error (pack signature mismatch detected)";
265
266 case PH_ERROR_PROTOCOL:
267 return "protocol error (pack version unsupported)";
268
269 default:
270 return "unknown error in parse_pack_header";
271
272 case 0:
273 return NULL;
274 }
275}
276
277static const char *pack_lockfile;
278
279static const char *unpack(void)
280{
281 struct pack_header hdr;
282 const char *hdr_err;
283 char hdr_arg[38];
284
285 hdr_err = parse_pack_header(&hdr);
286 if (hdr_err)
287 return hdr_err;
288 snprintf(hdr_arg, sizeof(hdr_arg), "--pack_header=%u,%u",
289 ntohl(hdr.hdr_version), ntohl(hdr.hdr_entries));
290
291 if (ntohl(hdr.hdr_entries) < unpack_limit) {
292 int code;
293 const char *unpacker[3];
294 unpacker[0] = "unpack-objects";
295 unpacker[1] = hdr_arg;
296 unpacker[2] = NULL;
297 code = run_command_v_opt(unpacker, RUN_GIT_CMD);
298 switch (code) {
299 case 0:
300 return NULL;
301 case -ERR_RUN_COMMAND_FORK:
302 return "unpack fork failed";
303 case -ERR_RUN_COMMAND_EXEC:
304 return "unpack execute failed";
305 case -ERR_RUN_COMMAND_WAITPID:
306 return "waitpid failed";
307 case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
308 return "waitpid is confused";
309 case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
310 return "unpacker died of signal";
311 case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
312 return "unpacker died strangely";
313 default:
314 return "unpacker exited with error code";
315 }
316 } else {
317 const char *keeper[6];
318 int fd[2], s, len, status;
319 pid_t pid;
320 char keep_arg[256];
321 char packname[46];
322
323 s = sprintf(keep_arg, "--keep=receive-pack %i on ", getpid());
324 if (gethostname(keep_arg + s, sizeof(keep_arg) - s))
325 strcpy(keep_arg + s, "localhost");
326
327 keeper[0] = "index-pack";
328 keeper[1] = "--stdin";
329 keeper[2] = "--fix-thin";
330 keeper[3] = hdr_arg;
331 keeper[4] = keep_arg;
332 keeper[5] = NULL;
333
334 if (pipe(fd) < 0)
335 return "index-pack pipe failed";
336 pid = fork();
337 if (pid < 0)
338 return "index-pack fork failed";
339 if (!pid) {
340 dup2(fd[1], 1);
341 close(fd[1]);
342 close(fd[0]);
343 execv_git_cmd(keeper);
344 die("execv of index-pack failed");
345 }
346 close(fd[1]);
347
348 /*
349 * The first thing we expects from index-pack's output
350 * is "pack\t%40s\n" or "keep\t%40s\n" (46 bytes) where
351 * %40s is the newly created pack SHA1 name. In the "keep"
352 * case, we need it to remove the corresponding .keep file
353 * later on. If we don't get that then tough luck with it.
354 */
355 for (len = 0;
356 len < 46 && (s = xread(fd[0], packname+len, 46-len)) > 0;
357 len += s);
358 close(fd[0]);
359 if (len == 46 && packname[45] == '\n' &&
360 memcmp(packname, "keep\t", 5) == 0) {
361 char path[PATH_MAX];
362 packname[45] = 0;
363 snprintf(path, sizeof(path), "%s/pack/pack-%s.keep",
364 get_object_directory(), packname + 5);
365 pack_lockfile = xstrdup(path);
366 }
367
368 /* Then wrap our index-pack process. */
369 while (waitpid(pid, &status, 0) < 0)
370 if (errno != EINTR)
371 return "waitpid failed";
372 if (WIFEXITED(status)) {
373 int code = WEXITSTATUS(status);
374 if (code)
375 return "index-pack exited with error code";
376 reprepare_packed_git();
377 return NULL;
378 }
379 return "index-pack abnormal exit";
380 }
381}
382
383static void report(const char *unpack_status)
384{
385 struct command *cmd;
386 packet_write(1, "unpack %s\n",
387 unpack_status ? unpack_status : "ok");
388 for (cmd = commands; cmd; cmd = cmd->next) {
389 if (!cmd->error_string)
390 packet_write(1, "ok %s\n",
391 cmd->ref_name);
392 else
393 packet_write(1, "ng %s %s\n",
394 cmd->ref_name, cmd->error_string);
395 }
396 packet_flush(1);
397}
398
399static int delete_only(struct command *cmd)
400{
401 while (cmd) {
402 if (!is_null_sha1(cmd->new_sha1))
403 return 0;
404 cmd = cmd->next;
405 }
406 return 1;
407}
408
409int main(int argc, char **argv)
410{
411 int i;
412 char *dir = NULL;
413
414 argv++;
415 for (i = 1; i < argc; i++) {
416 char *arg = *argv++;
417
418 if (*arg == '-') {
419 /* Do flag handling here */
420 usage(receive_pack_usage);
421 }
422 if (dir)
423 usage(receive_pack_usage);
424 dir = arg;
425 }
426 if (!dir)
427 usage(receive_pack_usage);
428
429 if (!enter_repo(dir, 0))
430 die("'%s': unable to chdir or not a git archive", dir);
431
432 if (is_repository_shallow())
433 die("attempt to push into a shallow repository");
434
435 git_config(receive_pack_config);
436
437 if (0 <= transfer_unpack_limit)
438 unpack_limit = transfer_unpack_limit;
439 else if (0 <= receive_unpack_limit)
440 unpack_limit = receive_unpack_limit;
441
442 write_head_info();
443
444 /* EOF */
445 packet_flush(1);
446
447 read_head_info();
448 if (commands) {
449 const char *unpack_status = NULL;
450
451 if (!delete_only(commands))
452 unpack_status = unpack();
453 if (!unpack_status)
454 execute_commands();
455 if (pack_lockfile)
456 unlink(pack_lockfile);
457 if (report_status)
458 report(unpack_status);
459 }
460 return 0;
461}