Merge branch 'sched'
[paraslash.git] / server.c
1 /*
2 * Copyright (C) 1997-2006 Andre Noll <maan@systemlinux.org>
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
17 */
18
19 /** \file server.c Paraslash's main server */
20
21
22 /** \mainpage Paraslash API Reference
23 *
24 * Good starting points for reading are probably \ref audio_file_selector,
25 * \ref sender, \ref receiver, \ref receiver_node, \ref filter, \ref
26 * filter_node.
27 *
28 */
29
30
31
32 #include "server.cmdline.h"
33 #include "db.h"
34 #include "server.h"
35 #include "afs.h"
36 #include "config.h"
37 #include "close_on_fork.h"
38 #include "send.h"
39 #include "error.h"
40 #include "net.h"
41 #include "daemon.h"
42 #include "string.h"
43 #include "ipc.h"
44 #include "fd.h"
45
46 /** define the array of error lists needed by para_server */
47 INIT_SERVER_ERRLISTS;
48
49 /** shut down non-authorized connections after that many seconds */
50 #define ALARM_TIMEOUT 10
51
52 /* these are exported to afs.c. command.c and to all selectors */
53 struct misc_meta_data *mmd;
54 /** the configuration of para_server
55 *
56 * It also contains the options for all audio file selectors and all supported
57 * senders.
58 */
59 struct gengetopt_args_info conf;
60 char *user_list = NULL;
61 extern void dccp_send_init(struct sender *);
62 extern void http_send_init(struct sender *);
63 extern void ortp_send_init(struct sender *);
64
65 /* TODO: This is better handled by autoconf */
66 /** the list of supported audio file selectors */
67 struct audio_file_selector selectors[] = {
68 {
69 .name = "random",
70 .init = random_selector_init,
71 .update_audio_file = NULL,
72 },
73 {
74 .name = "playlist",
75 .init = playlist_selector_init,
76 .update_audio_file = NULL,
77 .pre_select = NULL,
78 .post_select = NULL,
79 },
80 #ifdef HAVE_MYSQL
81 {
82 .name = "mysql",
83 .init = mysql_selector_init,
84 .update_audio_file = NULL,
85 .pre_select = NULL,
86 .post_select = NULL,
87 },
88 #endif
89 {
90 .name = NULL,
91 }
92 };
93
94 /** the list of supported senders */
95 struct sender senders[] = {
96 {
97 .name = "http",
98 .init = http_send_init,
99 },
100 {
101 .name = "dccp",
102 .init = dccp_send_init,
103 },
104 #ifdef HAVE_ORTP
105 {
106 .name = "ortp",
107 .init = ortp_send_init,
108 },
109 #endif
110 {
111 .name = NULL,
112 }
113 };
114
115
116 /* global variables for server-internal use */
117 static FILE *logfile;
118 static int mmd_mutex, mmd_shm_id;
119 static int signal_pipe;
120
121 /**
122 * para_server's log function
123 *
124 * \param ll the log level
125 * \param fmt the format string describing the log message
126 */
127 void para_log(int ll, const char* fmt,...)
128 {
129 va_list argp;
130 FILE *outfd;
131 struct tm *tm;
132 time_t t1;
133 char str[MAXLINE] = "";
134 pid_t mypid;
135
136 if (ll < conf.loglevel_arg)
137 return;
138 outfd = logfile? logfile : stderr;
139 time(&t1);
140 tm = localtime(&t1);
141 strftime(str, MAXLINE, "%b %d %H:%M:%S", tm);
142 fprintf(outfd, "%s ", str);
143 if (conf.loglevel_arg <= INFO)
144 fprintf(outfd, "%i: ", ll);
145 mypid = getpid();
146 if (conf.loglevel_arg <= INFO)
147 fprintf(outfd, "(%d) ", mypid);
148 va_start(argp, fmt);
149 vfprintf(outfd, fmt, argp);
150 va_end(argp);
151 }
152
153 /*
154 * setup shared memory area and get mutex for locking
155 */
156 static void shm_init(void)
157 {
158 void *shm;
159 int ret = shm_new(sizeof(struct misc_meta_data));
160
161 if (ret < 0)
162 goto err_out;
163
164 ret = shm_attach(ret, ATTACH_RW, &shm);
165 if (ret < 0)
166 goto err_out;
167 mmd = shm;
168 mmd_shm_id = ret;
169
170 ret = mutex_new();
171 if (ret < 0)
172 goto err_out;
173 mmd_mutex = ret;
174
175 mmd->selector_num = 0;
176 mmd->num_played = 0;
177 mmd->num_commands = 0;
178 mmd->events = 0;
179 mmd->num_connects = 0;
180 mmd->active_connections = 0;
181 strcpy(mmd->filename, "(none)");
182 mmd->audio_format = -1;
183 mmd->afs_status_flags = AFS_NEXT;
184 mmd->new_afs_status_flags = AFS_NEXT;
185 mmd->sender_cmd_data.cmd_num = -1;
186 return;
187 err_out:
188 PARA_EMERG_LOG("%s", PARA_STRERROR(-ret));
189 exit(EXIT_FAILURE);
190 }
191
192 /**
193 * lock the shared memory area containing the mmd struct
194 *
195 * \sa semop(2), struct misc_meta_data
196 */
197 void mmd_lock(void)
198 {
199 mutex_lock(mmd_mutex);
200 }
201
202 /**
203 * unlock the shared memory area containing the mmd struct
204 *
205 * \sa semop(2), struct misc_meta_data
206 */
207
208 void mmd_unlock(void)
209 {
210 mutex_unlock(mmd_mutex);
211 }
212
213 static void parse_config(int override)
214 {
215 char *home = para_homedir();
216 struct stat statbuf;
217 int ret;
218 char *cf;
219
220 if (conf.config_file_given)
221 cf = conf.config_file_arg;
222 else
223 cf = make_message("%s/.paraslash/server.conf", home);
224 free(user_list);
225 if (!conf.user_list_given)
226 user_list = make_message("%s/.paraslash/server.users", home);
227 else
228 user_list = para_strdup(conf.user_list_arg);
229 ret = stat(cf, &statbuf);
230 if (ret && conf.config_file_given) {
231 ret = -1;
232 PARA_EMERG_LOG("can not stat config file %s\n", cf);
233 goto out;
234 }
235 if (!ret) {
236 int tmp = conf.daemon_given;
237 cmdline_parser_configfile(cf, &conf, override, 0, 0);
238 conf.daemon_given = tmp;
239 }
240 /* logfile */
241 if (!conf.logfile_given && conf.daemon_given) {
242 ret = -1;
243 PARA_EMERG_LOG("%s", "daemon, but no log file\n");
244 goto out;
245 }
246 if (conf.logfile_given)
247 logfile = open_log(conf.logfile_arg);
248 ret = 1;
249 out:
250 free(cf);
251 free(home);
252 if (ret > 0)
253 return;
254 free(user_list);
255 user_list = NULL;
256 exit(EXIT_FAILURE);
257 }
258
259 static void setup_signal_handling(void)
260 {
261 int ret = 0;
262
263 signal_pipe = para_signal_init();
264 PARA_NOTICE_LOG("%s", "setting up signal handlers\n");
265 ret += para_install_sighandler(SIGINT);
266 ret += para_install_sighandler(SIGTERM);
267 ret += para_install_sighandler(SIGHUP);
268 ret += para_install_sighandler(SIGCHLD);
269 ret += para_install_sighandler(SIGUSR1);
270 signal(SIGPIPE, SIG_IGN);
271 if (ret != 5) {
272 PARA_EMERG_LOG("%s", "could not install signal handlers\n");
273 exit(EXIT_FAILURE);
274 }
275 }
276
277 static void init_selector(void)
278 {
279 int i, ret;
280
281 mmd->selector_change = -1; /* no change nec., set to new num by com_chs */
282 if (!conf.selector_given)
283 goto random;
284 for (i = 0; selectors[i].name; i++) {
285 if (strcmp(selectors[i].name, conf.selector_arg))
286 continue;
287 PARA_NOTICE_LOG("initializing %s audio file selector\n",
288 selectors[i].name);
289 ret = selectors[i].init(&selectors[i]);
290 if (ret < 0) {
291 PARA_WARNING_LOG("%s", PARA_STRERROR(-ret));
292 break;
293 }
294 mmd->selector_num = i;
295 return;
296 }
297 PARA_WARNING_LOG("%s", "falling back to the random selector\n");
298 random:
299 mmd->selector_num = 0;
300 selectors[0].init(&selectors[0]); /* always successful */
301 }
302
303 static unsigned init_network(void)
304 {
305 int sockfd = init_tcp_socket(conf.port_arg);
306
307 if (sockfd < 0)
308 exit(EXIT_FAILURE);
309 return sockfd;
310 }
311
312 static void init_random_seed(void)
313 {
314 int fd, ret = -1, len = sizeof(unsigned int);
315 unsigned int seed;
316
317 fd = open("/dev/urandom", O_RDONLY);
318 if (fd < 0)
319 goto out;
320 ret = -2;
321 if (read(fd, &seed, len) != len)
322 goto out;
323 srandom(seed);
324 ret = 1;
325 out:
326 if (fd >= 0)
327 close(fd);
328 if (ret > 0)
329 return;
330 PARA_EMERG_LOG("can not seed pseudo random generator (ret = %d)\n",
331 ret);
332 exit(EXIT_FAILURE);
333 }
334
335 static unsigned do_inits(int argc, char **argv)
336 {
337 /* connector's address information */
338 int sockfd;
339
340 init_random_seed();
341 /* parse command line options */
342 cmdline_parser(argc, argv, &conf);
343 para_drop_privileges(conf.user_arg, conf.group_arg);
344 /* parse config file, open log and set defaults */
345 parse_config(0);
346 log_welcome("para_server", conf.loglevel_arg);
347 shm_init(); /* init mmd struct */
348 server_uptime(UPTIME_SET); /* reset server uptime */
349 /* become daemon */
350 if (conf.daemon_given)
351 daemon_init();
352 init_selector();
353 PARA_NOTICE_LOG("%s", "initializing audio file sender\n");
354 /* audio file sender */
355 afs_init();
356 mmd->server_pid = getpid();
357 setup_signal_handling();
358 mmd_lock();
359 /* init network socket */
360 PARA_NOTICE_LOG("%s", "initializing tcp command socket\n");
361 sockfd = init_network();
362 if (conf.autoplay_given) {
363 mmd->afs_status_flags |= AFS_PLAYING;
364 mmd->new_afs_status_flags |= AFS_PLAYING;
365 }
366 PARA_NOTICE_LOG("%s", "init complete\n");
367 return sockfd;
368 }
369
370 static void change_selector(void)
371 {
372 int ret, old = mmd->selector_num, new = mmd->selector_change;
373
374 selectors[old].shutdown();
375 ret = selectors[new].init(&selectors[new]);
376 mmd->selector_change = -1; /* reset */
377 if (ret >= 0) {
378 mmd->selector_num = new;
379 return;
380 }
381 /* init failed */
382 PARA_ERROR_LOG("%s -- switching to the random selector\n", PARA_STRERROR(-ret));
383 selectors[0].init(&selectors[0]);
384 mmd->selector_num = 0;
385 }
386
387 /*
388 * called when server gets SIGHUP or when client invokes hup command.
389 */
390 static void handle_sighup(void)
391 {
392 PARA_NOTICE_LOG("%s", "SIGHUP\n");
393 close_log(logfile); /* gets reopened if necessary by parse_config */
394 logfile = NULL;
395 parse_config(1); /* reopens log */
396 mmd->selector_change = mmd->selector_num; /* do not change selector.. */
397 change_selector(); /* .. just reload */
398 }
399
400 static void status_refresh(void)
401 {
402 static int prev_uptime = -1, prev_events = -1;
403 int uptime = server_uptime(UPTIME_GET), ret = 1;
404
405 if (prev_events != mmd->events)
406 goto out;
407 if (mmd->new_afs_status_flags != mmd->afs_status_flags)
408 goto out;
409 if (uptime / 60 != prev_uptime / 60)
410 goto out;
411 ret = 0;
412 out:
413 prev_uptime = uptime;
414 prev_events = mmd->events;
415 mmd->afs_status_flags = mmd->new_afs_status_flags;
416 if (ret) {
417 PARA_DEBUG_LOG("%d events, forcing status update, af = %d\n",
418 mmd->events, mmd->audio_format);
419 killpg(0, SIGUSR1);
420 }
421 }
422
423 /*
424 * MAIN
425 */
426 int main(int argc, char *argv[])
427 {
428 /* listen on sock_fd, new connection on new_fd */
429 int sockfd, new_fd;
430 struct sockaddr_in their_addr;
431 int i, max_fileno, ret;
432 pid_t chld_pid;
433 fd_set rfds, wfds;
434 struct timeval *timeout;
435
436 valid_fd_012();
437 sockfd = do_inits(argc, argv);
438 repeat:
439 FD_ZERO(&rfds);
440 FD_ZERO(&wfds);
441 max_fileno = -1;
442 /* check socket and signal pipe in any case */
443 para_fd_set(sockfd, &rfds, &max_fileno);
444 para_fd_set(signal_pipe, &rfds, &max_fileno);
445 timeout = afs_preselect();
446 status_refresh();
447 for (i = 0; senders[i].name; i++) {
448 if (senders[i].status != SENDER_ON)
449 continue;
450 if (!senders[i].pre_select)
451 continue;
452 senders[i].pre_select( &max_fileno, &rfds, &wfds);
453 }
454 if (selectors[mmd->selector_num].pre_select) {
455 ret = selectors[mmd->selector_num].pre_select(&rfds, &wfds);
456 max_fileno = PARA_MAX(max_fileno, ret);
457 }
458 mmd_unlock();
459 ret = para_select(max_fileno + 1, &rfds, &wfds, timeout);
460 mmd_lock();
461 if (mmd->selector_change >= 0)
462 change_selector();
463 if (selectors[mmd->selector_num].post_select)
464 selectors[mmd->selector_num].post_select(&rfds, &wfds);
465 if (ret < 0)
466 goto repeat;
467 for (i = 0; senders[i].name; i++) {
468 if (senders[i].status != SENDER_ON)
469 continue;
470 if (!senders[i].post_select)
471 continue;
472 senders[i].post_select(&rfds, &wfds);
473 }
474 afs_send_chunk();
475 status_refresh();
476 if (FD_ISSET(signal_pipe, &rfds)) {
477 int sig;
478 sig = para_next_signal();
479 switch (sig) {
480 case SIGHUP:
481 handle_sighup();
482 break;
483 case SIGCHLD:
484 para_reap_children();
485 break;
486 /* die on sigint/sigterm. Kill all children too. */
487 case SIGINT:
488 case SIGTERM:
489 PARA_EMERG_LOG("terminating on signal %d\n", sig);
490 kill(0, SIGTERM);
491 selectors[mmd->selector_num].shutdown();
492 mutex_destroy(mmd_mutex);
493 shm_detach(mmd);
494 shm_destroy(mmd_shm_id);
495 exit(EXIT_FAILURE);
496 }
497 }
498 if (mmd->sender_cmd_data.cmd_num >= 0) {
499 int num = mmd->sender_cmd_data.cmd_num,
500 s = mmd->sender_cmd_data.sender_num;
501
502 if (senders[s].client_cmds[num])
503 senders[s].client_cmds[num](&mmd->sender_cmd_data);
504 mmd->sender_cmd_data.cmd_num = -1;
505 }
506 if (!FD_ISSET(sockfd, &rfds))
507 goto repeat;
508
509 new_fd = para_accept(sockfd, &their_addr, sizeof(struct sockaddr_in));
510 if (new_fd < 0)
511 goto repeat;
512 PARA_INFO_LOG("got connection from %s, forking\n",
513 inet_ntoa(their_addr.sin_addr));
514 mmd->num_connects++;
515 mmd->active_connections++;
516 random();
517 chld_pid = fork();
518 if (chld_pid < 0) {
519 PARA_CRIT_LOG("%s", "fork failed\n");
520 goto repeat;
521 }
522 if (chld_pid) {
523 close(new_fd);
524 /* parent keeps accepting connections */
525 goto repeat;
526 }
527 alarm(ALARM_TIMEOUT);
528 close_listed_fds();
529 close(sockfd); /* child doesn't need the listener */
530 /*
531 * put info on who we are serving into argv[0] to make
532 * client ip visible in top/ps
533 */
534 for (i = argc - 1; i >= 0; i--)
535 memset(argv[i], 0, strlen(argv[i]));
536 sprintf(argv[0], "para_server (serving %s)",
537 inet_ntoa(their_addr.sin_addr));
538 return handle_connect(new_fd, &their_addr);
539 }