Merge ../paraslash.fml/paraslash
[paraslash.git] / server.c
1 /*
2 * Copyright (C) 1997-2007 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 "vss.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 #include "signal.h"
46 #include "user_list.h"
47
48 /** define the array of error lists needed by para_server */
49 INIT_SERVER_ERRLISTS;
50
51 /** shut down non-authorized connections after that many seconds */
52 #define ALARM_TIMEOUT 10
53
54 /* these are exported to vss.c. command.c and to all selectors */
55 struct misc_meta_data *mmd;
56 /** the configuration of para_server
57 *
58 * It also contains the options for all audio file selectors and all supported
59 * senders.
60 */
61 struct server_args_info conf;
62 char *user_list_file = NULL;
63 extern void dccp_send_init(struct sender *);
64 extern void http_send_init(struct sender *);
65 extern void ortp_send_init(struct sender *);
66
67 /* TODO: This is better handled by autoconf */
68 /** the list of supported audio file selectors */
69 struct audio_file_selector selectors[] = {
70 {
71 .name = "random",
72 .init = random_selector_init,
73 .update_audio_file = NULL,
74 },
75 {
76 .name = "playlist",
77 .init = playlist_selector_init,
78 .update_audio_file = NULL,
79 .pre_select = NULL,
80 .post_select = NULL,
81 },
82 #ifdef HAVE_MYSQL
83 {
84 .name = "mysql",
85 .init = mysql_selector_init,
86 .update_audio_file = NULL,
87 .pre_select = NULL,
88 .post_select = NULL,
89 },
90 #endif
91 {
92 .name = NULL,
93 }
94 };
95
96 /** the list of supported senders */
97 struct sender senders[] = {
98 {
99 .name = "http",
100 .init = http_send_init,
101 },
102 {
103 .name = "dccp",
104 .init = dccp_send_init,
105 },
106 #ifdef HAVE_ORTP
107 {
108 .name = "ortp",
109 .init = ortp_send_init,
110 },
111 #endif
112 {
113 .name = NULL,
114 }
115 };
116
117
118 /* global variables for server-internal use */
119 static FILE *logfile;
120 static int mmd_mutex, mmd_shm_id;
121 static int signal_pipe;
122
123 /**
124 * para_server's log function
125 *
126 * \param ll the log level
127 * \param fmt the format string describing the log message
128 */
129 void para_log(int ll, const char* fmt,...)
130 {
131 va_list argp;
132 FILE *outfd;
133 struct tm *tm;
134 time_t t1;
135 char str[MAXLINE] = "";
136 pid_t mypid;
137
138 if (ll < conf.loglevel_arg)
139 return;
140 outfd = logfile? logfile : stderr;
141 time(&t1);
142 tm = localtime(&t1);
143 strftime(str, MAXLINE, "%b %d %H:%M:%S", tm);
144 fprintf(outfd, "%s ", str);
145 if (conf.loglevel_arg <= INFO)
146 fprintf(outfd, "%i: ", ll);
147 mypid = getpid();
148 if (conf.loglevel_arg <= INFO)
149 fprintf(outfd, "(%d) ", mypid);
150 va_start(argp, fmt);
151 vfprintf(outfd, fmt, argp);
152 va_end(argp);
153 }
154
155 /*
156 * setup shared memory area and get mutex for locking
157 */
158 static void shm_init(void)
159 {
160 void *shm;
161 int ret = shm_new(sizeof(struct misc_meta_data));
162
163 if (ret < 0)
164 goto err_out;
165
166 ret = shm_attach(ret, ATTACH_RW, &shm);
167 if (ret < 0)
168 goto err_out;
169 mmd = shm;
170 mmd_shm_id = ret;
171
172 ret = mutex_new();
173 if (ret < 0)
174 goto err_out;
175 mmd_mutex = ret;
176
177 mmd->selector_num = 0;
178 mmd->num_played = 0;
179 mmd->num_commands = 0;
180 mmd->events = 0;
181 mmd->num_connects = 0;
182 mmd->active_connections = 0;
183 strcpy(mmd->filename, "(none)");
184 mmd->audio_format = -1;
185 mmd->vss_status_flags = VSS_NEXT;
186 mmd->new_vss_status_flags = VSS_NEXT;
187 mmd->sender_cmd_data.cmd_num = -1;
188 return;
189 err_out:
190 PARA_EMERG_LOG("%s", PARA_STRERROR(-ret));
191 exit(EXIT_FAILURE);
192 }
193
194 /**
195 * lock the shared memory area containing the mmd struct
196 *
197 * \sa semop(2), struct misc_meta_data
198 */
199 void mmd_lock(void)
200 {
201 mutex_lock(mmd_mutex);
202 }
203
204 /**
205 * unlock the shared memory area containing the mmd struct
206 *
207 * \sa semop(2), struct misc_meta_data
208 */
209
210 void mmd_unlock(void)
211 {
212 mutex_unlock(mmd_mutex);
213 }
214
215 static void parse_config(int override)
216 {
217 char *home = para_homedir();
218 struct stat statbuf;
219 int ret;
220 char *cf;
221
222 if (conf.config_file_given)
223 cf = conf.config_file_arg;
224 else
225 cf = make_message("%s/.paraslash/server.conf", home);
226 free(user_list_file);
227 if (!conf.user_list_given)
228 user_list_file = make_message("%s/.paraslash/server.users", home);
229 else
230 user_list_file = para_strdup(conf.user_list_arg);
231 ret = stat(cf, &statbuf);
232 if (ret && conf.config_file_given) {
233 ret = -1;
234 PARA_EMERG_LOG("can not stat config file %s\n", cf);
235 goto out;
236 }
237 if (!ret) {
238 int tmp = conf.daemon_given;
239 server_cmdline_parser_configfile(cf, &conf, override, 0, 0);
240 conf.daemon_given = tmp;
241 }
242 /* logfile */
243 if (!conf.logfile_given && conf.daemon_given) {
244 ret = -1;
245 PARA_EMERG_LOG("%s", "daemon, but no log file\n");
246 goto out;
247 }
248 if (conf.logfile_given)
249 logfile = open_log(conf.logfile_arg);
250 ret = 1;
251 out:
252 free(cf);
253 free(home);
254 if (ret > 0)
255 return;
256 free(user_list_file);
257 user_list_file = NULL;
258 exit(EXIT_FAILURE);
259 }
260
261 static void setup_signal_handling(void)
262 {
263 int ret = 0;
264
265 signal_pipe = para_signal_init();
266 PARA_NOTICE_LOG("%s", "setting up signal handlers\n");
267 ret += para_install_sighandler(SIGINT);
268 ret += para_install_sighandler(SIGTERM);
269 ret += para_install_sighandler(SIGHUP);
270 ret += para_install_sighandler(SIGCHLD);
271 ret += para_install_sighandler(SIGUSR1);
272 signal(SIGPIPE, SIG_IGN);
273 if (ret != 5) {
274 PARA_EMERG_LOG("%s", "could not install signal handlers\n");
275 exit(EXIT_FAILURE);
276 }
277 }
278
279 static void init_selector(void)
280 {
281 int i, ret;
282
283 mmd->selector_change = -1; /* no change nec., set to new num by com_chs */
284 if (!conf.selector_given)
285 goto random;
286 for (i = 0; selectors[i].name; i++) {
287 if (strcmp(selectors[i].name, conf.selector_arg))
288 continue;
289 PARA_NOTICE_LOG("initializing %s audio file selector\n",
290 selectors[i].name);
291 ret = selectors[i].init(&selectors[i]);
292 if (ret < 0) {
293 PARA_WARNING_LOG("%s", PARA_STRERROR(-ret));
294 break;
295 }
296 mmd->selector_num = i;
297 return;
298 }
299 PARA_WARNING_LOG("%s", "falling back to the random selector\n");
300 random:
301 mmd->selector_num = 0;
302 selectors[0].init(&selectors[0]); /* always successful */
303 }
304
305 static unsigned init_network(void)
306 {
307 int fd, ret = init_tcp_socket(conf.port_arg);
308
309 if (ret < 0)
310 goto err;
311 fd = ret;
312 ret = mark_fd_nonblock(fd);
313 if (ret < 0)
314 goto err;
315 return fd;
316 err:
317 PARA_EMERG_LOG("%s\n", PARA_STRERROR(-ret));
318 exit(EXIT_FAILURE);
319 }
320
321 static void init_random_seed(void)
322 {
323 int fd, ret = -1, len = sizeof(unsigned int);
324 unsigned int seed;
325
326 fd = open("/dev/urandom", O_RDONLY);
327 if (fd < 0)
328 goto out;
329 ret = -2;
330 if (read(fd, &seed, len) != len)
331 goto out;
332 srandom(seed);
333 ret = 1;
334 out:
335 if (fd >= 0)
336 close(fd);
337 if (ret > 0)
338 return;
339 PARA_EMERG_LOG("can not seed pseudo random generator (ret = %d)\n",
340 ret);
341 exit(EXIT_FAILURE);
342 }
343
344 static unsigned do_inits(int argc, char **argv)
345 {
346 /* connector's address information */
347 int sockfd;
348
349 init_random_seed();
350 /* parse command line options */
351 server_cmdline_parser(argc, argv, &conf);
352 para_drop_privileges(conf.user_arg, conf.group_arg);
353 /* parse config file, open log and set defaults */
354 parse_config(0);
355 log_welcome("para_server", conf.loglevel_arg);
356 shm_init(); /* init mmd struct */
357 server_uptime(UPTIME_SET); /* reset server uptime */
358 init_user_list(user_list_file);
359 /* become daemon */
360 if (conf.daemon_given)
361 daemon_init();
362 init_selector();
363 PARA_NOTICE_LOG("%s", "initializing virtual streaming system\n");
364 vss_init();
365 mmd->server_pid = getpid();
366 setup_signal_handling();
367 mmd_lock();
368 /* init network socket */
369 PARA_NOTICE_LOG("%s", "initializing tcp command socket\n");
370 sockfd = init_network();
371 PARA_NOTICE_LOG("%s", "init complete\n");
372 return sockfd;
373 }
374
375 static void change_selector(void)
376 {
377 int ret, old = mmd->selector_num, new = mmd->selector_change;
378
379 selectors[old].shutdown();
380 ret = selectors[new].init(&selectors[new]);
381 mmd->selector_change = -1; /* reset */
382 if (ret >= 0) {
383 mmd->selector_num = new;
384 return;
385 }
386 /* init failed */
387 PARA_ERROR_LOG("%s -- switching to the random selector\n", PARA_STRERROR(-ret));
388 selectors[0].init(&selectors[0]);
389 mmd->selector_num = 0;
390 }
391
392 /*
393 * called when server gets SIGHUP or when client invokes hup command.
394 */
395 static void handle_sighup(void)
396 {
397 PARA_NOTICE_LOG("%s", "SIGHUP\n");
398 close_log(logfile); /* gets reopened if necessary by parse_config */
399 logfile = NULL;
400 parse_config(1); /* reopens log */
401 mmd->selector_change = mmd->selector_num; /* do not change selector.. */
402 change_selector(); /* .. just reload */
403 init_user_list(user_list_file); /* reload user list */
404 }
405
406 static void status_refresh(void)
407 {
408 static int prev_uptime = -1, prev_events = -1;
409 int uptime = server_uptime(UPTIME_GET), ret = 1;
410
411 if (prev_events != mmd->events)
412 goto out;
413 if (mmd->new_vss_status_flags != mmd->vss_status_flags)
414 goto out;
415 if (uptime / 60 != prev_uptime / 60)
416 goto out;
417 ret = 0;
418 out:
419 prev_uptime = uptime;
420 prev_events = mmd->events;
421 mmd->vss_status_flags = mmd->new_vss_status_flags;
422 if (ret) {
423 PARA_DEBUG_LOG("%d events, forcing status update, af = %d\n",
424 mmd->events, mmd->audio_format);
425 killpg(0, SIGUSR1);
426 }
427 }
428
429 /*
430 * MAIN
431 */
432 int main(int argc, char *argv[])
433 {
434 /* listen on sock_fd, new connection on new_fd */
435 int sockfd, new_fd;
436 struct sockaddr_in their_addr;
437 int i, max_fileno, ret;
438 pid_t chld_pid;
439 fd_set rfds, wfds;
440 struct timeval *timeout;
441
442 valid_fd_012();
443 sockfd = do_inits(argc, argv);
444 repeat:
445 FD_ZERO(&rfds);
446 FD_ZERO(&wfds);
447 max_fileno = -1;
448 /* check socket and signal pipe in any case */
449 para_fd_set(sockfd, &rfds, &max_fileno);
450 para_fd_set(signal_pipe, &rfds, &max_fileno);
451 timeout = vss_preselect();
452 status_refresh();
453 for (i = 0; senders[i].name; i++) {
454 if (senders[i].status != SENDER_ON)
455 continue;
456 if (!senders[i].pre_select)
457 continue;
458 senders[i].pre_select( &max_fileno, &rfds, &wfds);
459 }
460 if (selectors[mmd->selector_num].pre_select) {
461 ret = selectors[mmd->selector_num].pre_select(&rfds, &wfds);
462 max_fileno = PARA_MAX(max_fileno, ret);
463 }
464 mmd_unlock();
465 ret = para_select(max_fileno + 1, &rfds, &wfds, timeout);
466 mmd_lock();
467 if (mmd->selector_change >= 0)
468 change_selector();
469 if (selectors[mmd->selector_num].post_select)
470 selectors[mmd->selector_num].post_select(&rfds, &wfds);
471 if (ret < 0)
472 goto repeat;
473 for (i = 0; senders[i].name; i++) {
474 if (senders[i].status != SENDER_ON)
475 continue;
476 if (!senders[i].post_select)
477 continue;
478 senders[i].post_select(&rfds, &wfds);
479 }
480 vss_send_chunk();
481 status_refresh();
482 if (FD_ISSET(signal_pipe, &rfds)) {
483 int sig;
484 sig = para_next_signal();
485 switch (sig) {
486 case SIGHUP:
487 handle_sighup();
488 break;
489 case SIGCHLD:
490 para_reap_children();
491 break;
492 /* die on sigint/sigterm. Kill all children too. */
493 case SIGINT:
494 case SIGTERM:
495 PARA_EMERG_LOG("terminating on signal %d\n", sig);
496 kill(0, SIGTERM);
497 selectors[mmd->selector_num].shutdown();
498 mutex_destroy(mmd_mutex);
499 shm_detach(mmd);
500 shm_destroy(mmd_shm_id);
501 exit(EXIT_FAILURE);
502 }
503 }
504 if (mmd->sender_cmd_data.cmd_num >= 0) {
505 int num = mmd->sender_cmd_data.cmd_num,
506 s = mmd->sender_cmd_data.sender_num;
507
508 if (senders[s].client_cmds[num])
509 senders[s].client_cmds[num](&mmd->sender_cmd_data);
510 mmd->sender_cmd_data.cmd_num = -1;
511 }
512 if (!FD_ISSET(sockfd, &rfds))
513 goto repeat;
514
515 new_fd = para_accept(sockfd, &their_addr, sizeof(struct sockaddr_in));
516 if (new_fd < 0)
517 goto repeat;
518 PARA_INFO_LOG("got connection from %s, forking\n",
519 inet_ntoa(their_addr.sin_addr));
520 mmd->num_connects++;
521 mmd->active_connections++;
522 random();
523 chld_pid = fork();
524 if (chld_pid < 0) {
525 PARA_CRIT_LOG("%s", "fork failed\n");
526 goto repeat;
527 }
528 if (chld_pid) {
529 close(new_fd);
530 /* parent keeps accepting connections */
531 goto repeat;
532 }
533 alarm(ALARM_TIMEOUT);
534 close_listed_fds();
535 close(sockfd); /* child doesn't need the listener */
536 /*
537 * put info on who we are serving into argv[0] to make
538 * client ip visible in top/ps
539 */
540 for (i = argc - 1; i >= 0; i--)
541 memset(argv[i], 0, strlen(argv[i]));
542 sprintf(argv[0], "para_server (serving %s)",
543 inet_ntoa(their_addr.sin_addr));
544 return handle_connect(new_fd, &their_addr);
545 }