Documentation: update tutorial's discussion of origin
[git/dscho.git] / receive-pack.c
blobc176d8fd008ad858a1e60e19e7bf3ea14d735eb5
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"
10 static const char receive_pack_usage[] = "git-receive-pack <git-dir>";
12 static int deny_non_fast_forwards = 0;
13 static int unpack_limit = 100;
14 static int report_status;
16 static char capabilities[] = " report-status delete-refs ";
17 static int capabilities_sent;
19 static int receive_pack_config(const char *var, const char *value)
21 git_default_config(var, value);
23 if (strcmp(var, "receive.denynonfastforwards") == 0)
25 deny_non_fast_forwards = git_config_bool(var, value);
26 return 0;
29 if (strcmp(var, "receive.unpacklimit") == 0)
31 unpack_limit = git_config_int(var, value);
32 return 0;
35 return 0;
38 static int show_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
40 if (capabilities_sent)
41 packet_write(1, "%s %s\n", sha1_to_hex(sha1), path);
42 else
43 packet_write(1, "%s %s%c%s\n",
44 sha1_to_hex(sha1), path, 0, capabilities);
45 capabilities_sent = 1;
46 return 0;
49 static void write_head_info(void)
51 for_each_ref(show_ref, NULL);
52 if (!capabilities_sent)
53 show_ref("capabilities^{}", null_sha1, 0, NULL);
57 struct command {
58 struct command *next;
59 const char *error_string;
60 unsigned char old_sha1[20];
61 unsigned char new_sha1[20];
62 char ref_name[FLEX_ARRAY]; /* more */
65 static struct command *commands;
67 static char update_hook[] = "hooks/update";
69 static int run_update_hook(const char *refname,
70 char *old_hex, char *new_hex)
72 int code;
74 if (access(update_hook, X_OK) < 0)
75 return 0;
76 code = run_command_opt(RUN_COMMAND_NO_STDIN
77 | RUN_COMMAND_STDOUT_TO_STDERR,
78 update_hook, refname, old_hex, new_hex, NULL);
79 switch (code) {
80 case 0:
81 return 0;
82 case -ERR_RUN_COMMAND_FORK:
83 return error("hook fork failed");
84 case -ERR_RUN_COMMAND_EXEC:
85 return error("hook execute failed");
86 case -ERR_RUN_COMMAND_WAITPID:
87 return error("waitpid failed");
88 case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
89 return error("waitpid is confused");
90 case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
91 return error("%s died of signal", update_hook);
92 case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
93 return error("%s died strangely", update_hook);
94 default:
95 error("%s exited with error code %d", update_hook, -code);
96 return -code;
100 static int update(struct command *cmd)
102 const char *name = cmd->ref_name;
103 unsigned char *old_sha1 = cmd->old_sha1;
104 unsigned char *new_sha1 = cmd->new_sha1;
105 char new_hex[41], old_hex[41];
106 struct ref_lock *lock;
108 cmd->error_string = NULL;
109 if (!strncmp(name, "refs/", 5) && check_ref_format(name + 5)) {
110 cmd->error_string = "funny refname";
111 return error("refusing to create funny ref '%s' locally",
112 name);
115 strcpy(new_hex, sha1_to_hex(new_sha1));
116 strcpy(old_hex, sha1_to_hex(old_sha1));
118 if (!is_null_sha1(new_sha1) && !has_sha1_file(new_sha1)) {
119 cmd->error_string = "bad pack";
120 return error("unpack should have generated %s, "
121 "but I can't find it!", new_hex);
123 if (deny_non_fast_forwards && !is_null_sha1(new_sha1) &&
124 !is_null_sha1(old_sha1) &&
125 !strncmp(name, "refs/heads/", 11)) {
126 struct commit *old_commit, *new_commit;
127 struct commit_list *bases, *ent;
129 old_commit = (struct commit *)parse_object(old_sha1);
130 new_commit = (struct commit *)parse_object(new_sha1);
131 bases = get_merge_bases(old_commit, new_commit, 1);
132 for (ent = bases; ent; ent = ent->next)
133 if (!hashcmp(old_sha1, ent->item->object.sha1))
134 break;
135 free_commit_list(bases);
136 if (!ent)
137 return error("denying non-fast forward;"
138 " you should pull first");
140 if (run_update_hook(name, old_hex, new_hex)) {
141 cmd->error_string = "hook declined";
142 return error("hook declined to update %s", name);
145 if (is_null_sha1(new_sha1)) {
146 if (delete_ref(name, old_sha1)) {
147 cmd->error_string = "failed to delete";
148 return error("failed to delete %s", name);
150 fprintf(stderr, "%s: %s -> deleted\n", name, old_hex);
152 else {
153 lock = lock_any_ref_for_update(name, old_sha1);
154 if (!lock) {
155 cmd->error_string = "failed to lock";
156 return error("failed to lock %s", name);
158 write_ref_sha1(lock, new_sha1, "push");
159 fprintf(stderr, "%s: %s -> %s\n", name, old_hex, new_hex);
161 return 0;
164 static char update_post_hook[] = "hooks/post-update";
166 static void run_update_post_hook(struct command *cmd)
168 struct command *cmd_p;
169 int argc;
170 const char **argv;
172 if (access(update_post_hook, X_OK) < 0)
173 return;
174 for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
175 if (cmd_p->error_string)
176 continue;
177 argc++;
179 argv = xmalloc(sizeof(*argv) * (1 + argc));
180 argv[0] = update_post_hook;
182 for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
183 char *p;
184 if (cmd_p->error_string)
185 continue;
186 p = xmalloc(strlen(cmd_p->ref_name) + 1);
187 strcpy(p, cmd_p->ref_name);
188 argv[argc] = p;
189 argc++;
191 argv[argc] = NULL;
192 run_command_v_opt(argv, RUN_COMMAND_NO_STDIN
193 | RUN_COMMAND_STDOUT_TO_STDERR);
197 * This gets called after(if) we've successfully
198 * unpacked the data payload.
200 static void execute_commands(void)
202 struct command *cmd = commands;
204 while (cmd) {
205 update(cmd);
206 cmd = cmd->next;
208 run_update_post_hook(commands);
211 static void read_head_info(void)
213 struct command **p = &commands;
214 for (;;) {
215 static char line[1000];
216 unsigned char old_sha1[20], new_sha1[20];
217 struct command *cmd;
218 char *refname;
219 int len, reflen;
221 len = packet_read_line(0, line, sizeof(line));
222 if (!len)
223 break;
224 if (line[len-1] == '\n')
225 line[--len] = 0;
226 if (len < 83 ||
227 line[40] != ' ' ||
228 line[81] != ' ' ||
229 get_sha1_hex(line, old_sha1) ||
230 get_sha1_hex(line + 41, new_sha1))
231 die("protocol error: expected old/new/ref, got '%s'",
232 line);
234 refname = line + 82;
235 reflen = strlen(refname);
236 if (reflen + 82 < len) {
237 if (strstr(refname + reflen + 1, "report-status"))
238 report_status = 1;
240 cmd = xmalloc(sizeof(struct command) + len - 80);
241 hashcpy(cmd->old_sha1, old_sha1);
242 hashcpy(cmd->new_sha1, new_sha1);
243 memcpy(cmd->ref_name, line + 82, len - 81);
244 cmd->error_string = "n/a (unpacker error)";
245 cmd->next = NULL;
246 *p = cmd;
247 p = &cmd->next;
251 static const char *parse_pack_header(struct pack_header *hdr)
253 char *c = (char*)hdr;
254 ssize_t remaining = sizeof(struct pack_header);
255 do {
256 ssize_t r = xread(0, c, remaining);
257 if (r <= 0)
258 return "eof before pack header was fully read";
259 remaining -= r;
260 c += r;
261 } while (remaining > 0);
262 if (hdr->hdr_signature != htonl(PACK_SIGNATURE))
263 return "protocol error (pack signature mismatch detected)";
264 if (!pack_version_ok(hdr->hdr_version))
265 return "protocol error (pack version unsupported)";
266 return NULL;
269 static const char *pack_lockfile;
271 static const char *unpack(void)
273 struct pack_header hdr;
274 const char *hdr_err;
275 char hdr_arg[38];
277 hdr_err = parse_pack_header(&hdr);
278 if (hdr_err)
279 return hdr_err;
280 snprintf(hdr_arg, sizeof(hdr_arg), "--pack_header=%u,%u",
281 ntohl(hdr.hdr_version), ntohl(hdr.hdr_entries));
283 if (ntohl(hdr.hdr_entries) < unpack_limit) {
284 int code;
285 const char *unpacker[3];
286 unpacker[0] = "unpack-objects";
287 unpacker[1] = hdr_arg;
288 unpacker[2] = NULL;
289 code = run_command_v_opt(unpacker, RUN_GIT_CMD);
290 switch (code) {
291 case 0:
292 return NULL;
293 case -ERR_RUN_COMMAND_FORK:
294 return "unpack fork failed";
295 case -ERR_RUN_COMMAND_EXEC:
296 return "unpack execute failed";
297 case -ERR_RUN_COMMAND_WAITPID:
298 return "waitpid failed";
299 case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
300 return "waitpid is confused";
301 case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
302 return "unpacker died of signal";
303 case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
304 return "unpacker died strangely";
305 default:
306 return "unpacker exited with error code";
308 } else {
309 const char *keeper[6];
310 int fd[2], s, len, status;
311 pid_t pid;
312 char keep_arg[256];
313 char packname[46];
315 s = sprintf(keep_arg, "--keep=receive-pack %i on ", getpid());
316 if (gethostname(keep_arg + s, sizeof(keep_arg) - s))
317 strcpy(keep_arg + s, "localhost");
319 keeper[0] = "index-pack";
320 keeper[1] = "--stdin";
321 keeper[2] = "--fix-thin";
322 keeper[3] = hdr_arg;
323 keeper[4] = keep_arg;
324 keeper[5] = NULL;
326 if (pipe(fd) < 0)
327 return "index-pack pipe failed";
328 pid = fork();
329 if (pid < 0)
330 return "index-pack fork failed";
331 if (!pid) {
332 dup2(fd[1], 1);
333 close(fd[1]);
334 close(fd[0]);
335 execv_git_cmd(keeper);
336 die("execv of index-pack failed");
338 close(fd[1]);
341 * The first thing we expects from index-pack's output
342 * is "pack\t%40s\n" or "keep\t%40s\n" (46 bytes) where
343 * %40s is the newly created pack SHA1 name. In the "keep"
344 * case, we need it to remove the corresponding .keep file
345 * later on. If we don't get that then tough luck with it.
347 for (len = 0;
348 len < 46 && (s = xread(fd[0], packname+len, 46-len)) > 0;
349 len += s);
350 close(fd[0]);
351 if (len == 46 && packname[45] == '\n' &&
352 memcmp(packname, "keep\t", 5) == 0) {
353 char path[PATH_MAX];
354 packname[45] = 0;
355 snprintf(path, sizeof(path), "%s/pack/pack-%s.keep",
356 get_object_directory(), packname + 5);
357 pack_lockfile = xstrdup(path);
360 /* Then wrap our index-pack process. */
361 while (waitpid(pid, &status, 0) < 0)
362 if (errno != EINTR)
363 return "waitpid failed";
364 if (WIFEXITED(status)) {
365 int code = WEXITSTATUS(status);
366 if (code)
367 return "index-pack exited with error code";
368 reprepare_packed_git();
369 return NULL;
371 return "index-pack abnormal exit";
375 static void report(const char *unpack_status)
377 struct command *cmd;
378 packet_write(1, "unpack %s\n",
379 unpack_status ? unpack_status : "ok");
380 for (cmd = commands; cmd; cmd = cmd->next) {
381 if (!cmd->error_string)
382 packet_write(1, "ok %s\n",
383 cmd->ref_name);
384 else
385 packet_write(1, "ng %s %s\n",
386 cmd->ref_name, cmd->error_string);
388 packet_flush(1);
391 static int delete_only(struct command *cmd)
393 while (cmd) {
394 if (!is_null_sha1(cmd->new_sha1))
395 return 0;
396 cmd = cmd->next;
398 return 1;
401 int main(int argc, char **argv)
403 int i;
404 char *dir = NULL;
406 argv++;
407 for (i = 1; i < argc; i++) {
408 char *arg = *argv++;
410 if (*arg == '-') {
411 /* Do flag handling here */
412 usage(receive_pack_usage);
414 if (dir)
415 usage(receive_pack_usage);
416 dir = arg;
418 if (!dir)
419 usage(receive_pack_usage);
421 if (!enter_repo(dir, 0))
422 die("'%s': unable to chdir or not a git archive", dir);
424 setup_ident();
425 /* don't die if gecos is empty */
426 ignore_missing_committer_name();
427 git_config(receive_pack_config);
429 write_head_info();
431 /* EOF */
432 packet_flush(1);
434 read_head_info();
435 if (commands) {
436 const char *unpack_status = NULL;
438 if (!delete_only(commands))
439 unpack_status = unpack();
440 if (!unpack_status)
441 execute_commands();
442 if (pack_lockfile)
443 unlink(pack_lockfile);
444 if (report_status)
445 report(unpack_status);
447 return 0;