1 /* $NetBSD: dgram_server.c,v 1.3 2022/10/08 16:12:46 christos Exp $ */
2
3 /*++
4 /* NAME
5 /* dgram_server 3
6 /* SUMMARY
7 /* skeleton datagram server subsystem
8 /* SYNOPSIS
9 /* #include <mail_server.h>
10 /*
11 /* NORETURN dgram_server_main(argc, argv, service, key, value, ...)
12 /* int argc;
13 /* char **argv;
14 /* void (*service)(char *buf, int len, char *service_name, char **argv);
15 /* int key;
16 /* DESCRIPTION
17 /* This module implements a skeleton for mail subsystem programs
18 /* that wake up on client request and perform some activity
19 /* without further client interaction. This module supports
20 /* local IPC via a UNIX-domain datagram socket. The resulting
21 /* program expects to be run from the \fBmaster\fR process.
22 /*
23 /* dgram_server_main() is the skeleton entry point. It should
24 /* be called from the application main program. The skeleton
25 /* does the generic command-line options processing, initialization
26 /* of configurable parameters, and receiving datagrams. The
27 /* skeleton never returns.
28 /*
29 /* Arguments:
30 /* .IP "void (*service)(char *buf, int len, char *service_name, char **argv)"
31 /* A pointer to a function that is called by the skeleton each
32 /* time a client sends a datagram to the program's service
33 /* port. The function is run after the program has irrevocably
34 /* dropped its privileges. The buffer argument specifies the
35 /* data read from the datagram port; this data corresponds to
36 /* request. The len argument specifies how much client data
37 /* is available. The maximal size of the buffer is specified
38 /* via the DGRAM_BUF_SIZE manifest constant. The service name
39 /* argument corresponds to the service name in the master.cf
40 /* file. The argv argument specifies command-line arguments
41 /* left over after options processing.
42 /* .PP
43 /* Optional arguments are specified as a null-terminated list
44 /* with macros that have zero or more arguments:
45 /* .IP "CA_MAIL_SERVER_INT_TABLE(CONFIG_INT_TABLE *)"
46 /* A table with configurable parameters, to be loaded from the
47 /* global Postfix configuration file. Tables are loaded in the
48 /* order as specified, and multiple instances of the same type
49 /* are allowed.
50 /* .IP "CA_MAIL_SERVER_LONG_TABLE(CONFIG_LONG_TABLE *)"
51 /* A table with configurable parameters, to be loaded from the
52 /* global Postfix configuration file. Tables are loaded in the
53 /* order as specified, and multiple instances of the same type
54 /* are allowed.
55 /* .IP "CA_MAIL_SERVER_STR_TABLE(CONFIG_STR_TABLE *)"
56 /* A table with configurable parameters, to be loaded from the
57 /* global Postfix configuration file. Tables are loaded in the
58 /* order as specified, and multiple instances of the same type
59 /* are allowed.
60 /* .IP "CA_MAIL_SERVER_BOOL_TABLE(CONFIG_BOOL_TABLE *)"
61 /* A table with configurable parameters, to be loaded from the
62 /* global Postfix configuration file. Tables are loaded in the
63 /* order as specified, and multiple instances of the same type
64 /* are allowed.
65 /* .IP "CA_MAIL_SERVER_TIME_TABLE(CONFIG_TIME_TABLE *)"
66 /* A table with configurable parameters, to be loaded from the
67 /* global Postfix configuration file. Tables are loaded in the
68 /* order as specified, and multiple instances of the same type
69 /* are allowed.
70 /* .IP "CA_MAIL_SERVER_RAW_TABLE(CONFIG_RAW_TABLE *)"
71 /* A table with configurable parameters, to be loaded from the
72 /* global Postfix configuration file. Tables are loaded in the
73 /* order as specified, and multiple instances of the same type
74 /* are allowed. Raw parameters are not subjected to $name
75 /* evaluation.
76 /* .IP "CA_MAIL_SERVER_NINT_TABLE(CONFIG_NINT_TABLE *)"
77 /* A table with configurable parameters, to be loaded from the
78 /* global Postfix configuration file. Tables are loaded in the
79 /* order as specified, and multiple instances of the same type
80 /* are allowed.
81 /* .IP "CA_MAIL_SERVER_NBOOL_TABLE(CONFIG_NBOOL_TABLE *)"
82 /* A table with configurable parameters, to be loaded from the
83 /* global Postfix configuration file. Tables are loaded in the
84 /* order as specified, and multiple instances of the same type
85 /* are allowed.
86 /* .IP "CA_MAIL_SERVER_PRE_INIT(void *(char *service_name, char **argv))"
87 /* A pointer to a function that is called once
88 /* by the skeleton after it has read the global configuration file
89 /* and after it has processed command-line arguments, but before
90 /* the skeleton has optionally relinquished the process privileges.
91 /* .sp
92 /* Only the last instance of this parameter type is remembered.
93 /* .IP "CA_MAIL_SERVER_POST_INIT(void *(char *service_name, char **argv))"
94 /* A pointer to a function that is called once
95 /* by the skeleton after it has optionally relinquished the process
96 /* privileges, but before servicing client connection requests.
97 /* .sp
98 /* Only the last instance of this parameter type is remembered.
99 /* .IP "CA_MAIL_SERVER_LOOP(int *(char *service_name, char **argv))"
100 /* A pointer to function that is executed from
101 /* within the event loop, whenever an I/O or timer event has happened,
102 /* or whenever nothing has happened for a specified amount of time.
103 /* The result value of the function specifies how long to wait until
104 /* the next event. Specify -1 to wait for "as long as it takes".
105 /* .sp
106 /* Only the last instance of this parameter type is remembered.
107 /* .IP "CA_MAIL_SERVER_EXIT(void *(char *service_name, char **argv))"
108 /* A pointer to function that is executed immediately before normal
109 /* process termination.
110 /* .sp
111 /* Only the last instance of this parameter type is remembered.
112 /* .IP "CA_MAIL_SERVER_PRE_ACCEPT(void *(char *service_name, char **argv))"
113 /* Function to be executed prior to accepting a new request.
114 /* .sp
115 /* Only the last instance of this parameter type is remembered.
116 /* .IP "CA_MAIL_SERVER_IN_FLOW_DELAY(none)"
117 /* Pause $in_flow_delay seconds when no "mail flow control token"
118 /* is available. A token is consumed for each connection request.
119 /* .IP CA_MAIL_SERVER_SOLITARY
120 /* This service must be configured with process limit of 1.
121 /* .IP CA_MAIL_SERVER_UNLIMITED
122 /* This service must be configured with process limit of 0.
123 /* .IP CA_MAIL_SERVER_PRIVILEGED
124 /* This service must be configured as privileged.
125 /* .IP "CA_MAIL_SERVER_WATCHDOG(int *)"
126 /* Override the default 1000s watchdog timeout. The value is
127 /* used after command-line and main.cf file processing.
128 /* .IP "CA_MAIL_SERVER_BOUNCE_INIT(const char *, const char **)"
129 /* Initialize the DSN filter for the bounce/defer service
130 /* clients with the specified map source and map names.
131 /* .PP
132 /* The var_use_limit variable limits the number of clients that
133 /* a server can service before it commits suicide.
134 /* This value is taken from the global \fBmain.cf\fR configuration
135 /* file. Setting \fBvar_use_limit\fR to zero disables the client limit.
136 /*
137 /* The var_idle_limit variable limits the time that a service
138 /* receives no client connection requests before it commits suicide.
139 /* This value is taken from the global \fBmain.cf\fR configuration
140 /* file. Setting \fBvar_use_limit\fR to zero disables the idle limit.
141 /* DIAGNOSTICS
142 /* Problems and transactions are logged to \fBsyslogd\fR(8)
143 /* or \fBpostlogd\fR(8).
144 /* SEE ALSO
145 /* master(8), master process
146 /* postlogd(8), Postfix logging
147 /* syslogd(8), system logging
148 /* LICENSE
149 /* .ad
150 /* .fi
151 /* The Secure Mailer license must be distributed with this software.
152 /* AUTHOR(S)
153 /* Wietse Venema
154 /* Google, Inc.
155 /* 111 8th Avenue
156 /* New York, NY 10011, USA
157 /*--*/
158
159 /* System library. */
160
161 #include <sys_defs.h>
162 #include <sys/socket.h>
163 #include <unistd.h>
164 #include <signal.h>
165 #include <stdlib.h>
166 #include <limits.h>
167 #include <string.h>
168 #include <errno.h>
169 #include <fcntl.h>
170 #include <stdarg.h>
171 #ifdef STRCASECMP_IN_STRINGS_H
172 #include <strings.h>
173 #endif
174 #include <time.h>
175
176 /* Utility library. */
177
178 #include <msg.h>
179 #include <msg_vstream.h>
180 #include <chroot_uid.h>
181 #include <vstring.h>
182 #include <vstream.h>
183 #include <msg_vstream.h>
184 #include <mymalloc.h>
185 #include <events.h>
186 #include <iostuff.h>
187 #include <stringops.h>
188 #include <sane_accept.h>
189 #include <myflock.h>
190 #include <safe_open.h>
191 #include <listen.h>
192 #include <watchdog.h>
193 #include <split_at.h>
194
195 /* Global library. */
196
197 #include <mail_params.h>
198 #include <mail_task.h>
199 #include <debug_process.h>
200 #include <mail_conf.h>
201 #include <mail_dict.h>
202 #include <resolve_local.h>
203 #include <mail_flow.h>
204 #include <mail_version.h>
205 #include <bounce.h>
206 #include <maillog_client.h>
207
208 /* Process manager. */
209
210 #include "master_proto.h"
211
212 /* Application-specific */
213
214 #include "mail_server.h"
215
216 /*
217 * Global state.
218 */
219 static int use_count;
220
221 static DGRAM_SERVER_FN dgram_server_service;
222 static char *dgram_server_name;
223 static char **dgram_server_argv;
224 static void (*dgram_server_accept) (int, void *);
225 static void (*dgram_server_onexit) (char *, char **);
226 static void (*dgram_server_pre_accept) (char *, char **);
227 static VSTREAM *dgram_server_lock;
228 static int dgram_server_in_flow_delay;
229 static unsigned dgram_server_generation;
230 static int dgram_server_watchdog = 1000;
231
232 /* dgram_server_exit - normal termination */
233
dgram_server_exit(void)234 static NORETURN dgram_server_exit(void)
235 {
236 if (dgram_server_onexit)
237 dgram_server_onexit(dgram_server_name, dgram_server_argv);
238 exit(0);
239 }
240
241 /* dgram_server_abort - terminate after abnormal master exit */
242
dgram_server_abort(int unused_event,void * unused_context)243 static void dgram_server_abort(int unused_event, void *unused_context)
244 {
245 if (msg_verbose)
246 msg_info("master disconnect -- exiting");
247 dgram_server_exit();
248 }
249
250 /* dgram_server_timeout - idle time exceeded */
251
dgram_server_timeout(int unused_event,void * unused_context)252 static void dgram_server_timeout(int unused_event, void *unused_context)
253 {
254 if (msg_verbose)
255 msg_info("idle timeout -- exiting");
256 dgram_server_exit();
257 }
258
259 /* dgram_server_wakeup - wake up application */
260
dgram_server_wakeup(int fd)261 static void dgram_server_wakeup(int fd)
262 {
263 char buf[DGRAM_BUF_SIZE];
264 ssize_t len;
265
266 /*
267 * Commit suicide when the master process disconnected from us, after
268 * handling the client request.
269 */
270 if (master_notify(var_pid, dgram_server_generation, MASTER_STAT_TAKEN) < 0)
271 /* void */ ;
272 if (dgram_server_in_flow_delay && mail_flow_get(1) < 0)
273 doze(var_in_flow_delay * 1000000);
274 if ((len = recv(fd, buf, sizeof(buf), 0)) >= 0)
275 dgram_server_service(buf, len, dgram_server_name, dgram_server_argv);
276 if (master_notify(var_pid, dgram_server_generation, MASTER_STAT_AVAIL) < 0)
277 dgram_server_abort(EVENT_NULL_TYPE, EVENT_NULL_CONTEXT);
278 if (var_idle_limit > 0)
279 event_request_timer(dgram_server_timeout, (void *) 0, var_idle_limit);
280 /* Avoid integer wrap-around in a persistent process. */
281 if (use_count < INT_MAX)
282 use_count++;
283 }
284
285 /* dgram_server_accept_unix - handle UNIX-domain socket event */
286
dgram_server_accept_unix(int unused_event,void * context)287 static void dgram_server_accept_unix(int unused_event, void *context)
288 {
289 const char *myname = "dgram_server_accept";
290 int listen_fd = CAST_ANY_PTR_TO_INT(context);
291
292 if (dgram_server_lock != 0
293 && myflock(vstream_fileno(dgram_server_lock), INTERNAL_LOCK,
294 MYFLOCK_OP_NONE) < 0)
295 msg_fatal("select unlock: %m");
296
297 if (msg_verbose)
298 msg_info("%s: request arrived", myname);
299
300 /*
301 * Read whatever the other side wrote. The socket is non-blocking so we
302 * won't get stuck when multiple processes wake up.
303 */
304 if (dgram_server_pre_accept)
305 dgram_server_pre_accept(dgram_server_name, dgram_server_argv);
306 dgram_server_wakeup(listen_fd);
307 }
308
309 /* dgram_server_main - the real main program */
310
dgram_server_main(int argc,char ** argv,DGRAM_SERVER_FN service,...)311 NORETURN dgram_server_main(int argc, char **argv, DGRAM_SERVER_FN service,...)
312 {
313 const char *myname = "dgram_server_main";
314 char *root_dir = 0;
315 char *user_name = 0;
316 int debug_me = 0;
317 int daemon_mode = 1;
318 char *service_name = basename(argv[0]);
319 int delay;
320 int c;
321 int socket_count = 1;
322 int fd;
323 va_list ap;
324 MAIL_SERVER_INIT_FN pre_init = 0;
325 MAIL_SERVER_INIT_FN post_init = 0;
326 MAIL_SERVER_LOOP_FN loop = 0;
327 int key;
328 char *transport = 0;
329 char *lock_path;
330 VSTRING *why;
331 int alone = 0;
332 int zerolimit = 0;
333 WATCHDOG *watchdog;
334 char *oname_val;
335 char *oname;
336 char *oval;
337 const char *err;
338 char *generation;
339 int msg_vstream_needed = 0;
340 const char *dsn_filter_title;
341 const char **dsn_filter_maps;
342
343 /*
344 * Process environment options as early as we can.
345 */
346 if (getenv(CONF_ENV_VERB))
347 msg_verbose = 1;
348 if (getenv(CONF_ENV_DEBUG))
349 debug_me = 1;
350
351 /*
352 * Don't die when a process goes away unexpectedly.
353 */
354 signal(SIGPIPE, SIG_IGN);
355
356 /*
357 * Don't die for frivolous reasons.
358 */
359 #ifdef SIGXFSZ
360 signal(SIGXFSZ, SIG_IGN);
361 #endif
362
363 /*
364 * May need this every now and then.
365 */
366 var_procname = mystrdup(basename(argv[0]));
367 set_mail_conf_str(VAR_PROCNAME, var_procname);
368
369 /*
370 * Initialize logging and exit handler. Do the syslog first, so that its
371 * initialization completes before we enter the optional chroot jail.
372 */
373 maillog_client_init(mail_task(var_procname), MAILLOG_CLIENT_FLAG_NONE);
374 if (msg_verbose)
375 msg_info("daemon started");
376
377 /*
378 * Check the Postfix library version as soon as we enable logging.
379 */
380 MAIL_VERSION_CHECK;
381
382 /*
383 * Initialize from the configuration file. Allow command-line options to
384 * override compiled-in defaults or configured parameter values.
385 */
386 mail_conf_suck();
387
388 /*
389 * After database open error, continue execution with reduced
390 * functionality.
391 */
392 dict_allow_surrogate = 1;
393
394 /*
395 * Pick up policy settings from master process. Shut up error messages to
396 * stderr, because no-one is going to see them.
397 */
398 opterr = 0;
399 while ((c = GETOPT(argc, argv, "cdDi:lm:n:o:s:t:uvVz")) > 0) {
400 switch (c) {
401 case 'c':
402 root_dir = "setme";
403 break;
404 case 'd':
405 daemon_mode = 0;
406 break;
407 case 'D':
408 debug_me = 1;
409 break;
410 case 'i':
411 mail_conf_update(VAR_MAX_IDLE, optarg);
412 break;
413 case 'l':
414 alone = 1;
415 break;
416 case 'm':
417 mail_conf_update(VAR_MAX_USE, optarg);
418 break;
419 case 'n':
420 service_name = optarg;
421 break;
422 case 'o':
423 oname_val = mystrdup(optarg);
424 if ((err = split_nameval(oname_val, &oname, &oval)) != 0)
425 msg_fatal("invalid \"-o %s\" option value: %s", optarg, err);
426 mail_conf_update(oname, oval);
427 myfree(oname_val);
428 break;
429 case 's':
430 if ((socket_count = atoi(optarg)) <= 0)
431 msg_fatal("invalid socket_count: %s", optarg);
432 break;
433 case 't':
434 transport = optarg;
435 break;
436 case 'u':
437 user_name = "setme";
438 break;
439 case 'v':
440 msg_verbose++;
441 break;
442 case 'V':
443 if (++msg_vstream_needed == 1)
444 msg_vstream_init(mail_task(var_procname), VSTREAM_ERR);
445 break;
446 case 'z':
447 zerolimit = 1;
448 break;
449 default:
450 msg_fatal("invalid option: %c", optopt);
451 break;
452 }
453 }
454 set_mail_conf_str(VAR_SERVNAME, service_name);
455
456 /*
457 * Initialize generic parameters and re-initialize logging in case of a
458 * non-default program name or logging destination.
459 */
460 mail_params_init();
461 maillog_client_init(mail_task(var_procname), MAILLOG_CLIENT_FLAG_NONE);
462
463 /*
464 * Register higher-level dictionaries and initialize the support for
465 * dynamically-loaded dictionaries.
466 */
467 mail_dict_init();
468
469 /*
470 * If not connected to stdin, stdin must not be a terminal.
471 */
472 if (daemon_mode && isatty(STDIN_FILENO)) {
473 msg_vstream_init(var_procname, VSTREAM_ERR);
474 msg_fatal("do not run this command by hand");
475 }
476
477 /*
478 * Application-specific initialization.
479 */
480 va_start(ap, service);
481 while ((key = va_arg(ap, int)) != 0) {
482 switch (key) {
483 case MAIL_SERVER_INT_TABLE:
484 get_mail_conf_int_table(va_arg(ap, CONFIG_INT_TABLE *));
485 break;
486 case MAIL_SERVER_LONG_TABLE:
487 get_mail_conf_long_table(va_arg(ap, CONFIG_LONG_TABLE *));
488 break;
489 case MAIL_SERVER_STR_TABLE:
490 get_mail_conf_str_table(va_arg(ap, CONFIG_STR_TABLE *));
491 break;
492 case MAIL_SERVER_BOOL_TABLE:
493 get_mail_conf_bool_table(va_arg(ap, CONFIG_BOOL_TABLE *));
494 break;
495 case MAIL_SERVER_TIME_TABLE:
496 get_mail_conf_time_table(va_arg(ap, CONFIG_TIME_TABLE *));
497 break;
498 case MAIL_SERVER_RAW_TABLE:
499 get_mail_conf_raw_table(va_arg(ap, CONFIG_RAW_TABLE *));
500 break;
501 case MAIL_SERVER_NINT_TABLE:
502 get_mail_conf_nint_table(va_arg(ap, CONFIG_NINT_TABLE *));
503 break;
504 case MAIL_SERVER_NBOOL_TABLE:
505 get_mail_conf_nbool_table(va_arg(ap, CONFIG_NBOOL_TABLE *));
506 break;
507 case MAIL_SERVER_PRE_INIT:
508 pre_init = va_arg(ap, MAIL_SERVER_INIT_FN);
509 break;
510 case MAIL_SERVER_POST_INIT:
511 post_init = va_arg(ap, MAIL_SERVER_INIT_FN);
512 break;
513 case MAIL_SERVER_LOOP:
514 loop = va_arg(ap, MAIL_SERVER_LOOP_FN);
515 break;
516 case MAIL_SERVER_EXIT:
517 dgram_server_onexit = va_arg(ap, MAIL_SERVER_EXIT_FN);
518 break;
519 case MAIL_SERVER_PRE_ACCEPT:
520 dgram_server_pre_accept = va_arg(ap, MAIL_SERVER_ACCEPT_FN);
521 break;
522 case MAIL_SERVER_IN_FLOW_DELAY:
523 dgram_server_in_flow_delay = 1;
524 break;
525 case MAIL_SERVER_SOLITARY:
526 if (!alone)
527 msg_fatal("service %s requires a process limit of 1",
528 service_name);
529 break;
530 case MAIL_SERVER_UNLIMITED:
531 if (!zerolimit)
532 msg_fatal("service %s requires a process limit of 0",
533 service_name);
534 break;
535 case MAIL_SERVER_PRIVILEGED:
536 if (user_name)
537 msg_fatal("service %s requires privileged operation",
538 service_name);
539 break;
540 case MAIL_SERVER_WATCHDOG:
541 dgram_server_watchdog = *va_arg(ap, int *);
542 break;
543 case MAIL_SERVER_BOUNCE_INIT:
544 dsn_filter_title = va_arg(ap, const char *);
545 dsn_filter_maps = va_arg(ap, const char **);
546 bounce_client_init(dsn_filter_title, *dsn_filter_maps);
547 break;
548 default:
549 msg_panic("%s: unknown argument type: %d", myname, key);
550 }
551 }
552 va_end(ap);
553
554 if (root_dir)
555 root_dir = var_queue_dir;
556 if (user_name)
557 user_name = var_mail_owner;
558
559 /*
560 * Can options be required?
561 */
562 if (transport == 0)
563 msg_fatal("no transport type specified");
564 else if (strcasecmp(transport, MASTER_XPORT_NAME_UXDG) == 0)
565 dgram_server_accept = dgram_server_accept_unix;
566 else
567 msg_fatal("unsupported transport type: %s", transport);
568
569 /*
570 * Retrieve process generation from environment.
571 */
572 if ((generation = getenv(MASTER_GEN_NAME)) != 0) {
573 if (!alldig(generation))
574 msg_fatal("bad generation: %s", generation);
575 OCTAL_TO_UNSIGNED(dgram_server_generation, generation);
576 if (msg_verbose)
577 msg_info("process generation: %s (%o)",
578 generation, dgram_server_generation);
579 }
580
581 /*
582 * Optionally start the debugger on ourself.
583 */
584 if (debug_me)
585 debug_process();
586
587 /*
588 * Traditionally, BSD select() can't handle multiple processes selecting
589 * on the same socket, and wakes up every process in select(). See TCP/IP
590 * Illustrated volume 2 page 532. We avoid select() collisions with an
591 * external lock file.
592 */
593 if (!alone) {
594 lock_path = concatenate(DEF_PID_DIR, "/", transport,
595 ".", service_name, (char *) 0);
596 why = vstring_alloc(1);
597 if ((dgram_server_lock = safe_open(lock_path, O_CREAT | O_RDWR, 0600,
598 (struct stat *) 0, -1, -1, why)) == 0)
599 msg_fatal("open lock file %s: %s", lock_path, vstring_str(why));
600 close_on_exec(vstream_fileno(dgram_server_lock), CLOSE_ON_EXEC);
601 myfree(lock_path);
602 vstring_free(why);
603 }
604
605 /*
606 * Set up call-back info.
607 */
608 dgram_server_service = service;
609 dgram_server_name = service_name;
610 dgram_server_argv = argv + optind;
611
612 /*
613 * Run pre-jail initialization.
614 */
615 if (chdir(var_queue_dir) < 0)
616 msg_fatal("chdir(\"%s\"): %m", var_queue_dir);
617 if (pre_init)
618 pre_init(dgram_server_name, dgram_server_argv);
619
620 /*
621 * Optionally, restrict the damage that this process can do.
622 */
623 resolve_local_init();
624 tzset();
625 chroot_uid(root_dir, user_name);
626
627 /*
628 * Run post-jail initialization.
629 */
630 if (post_init)
631 post_init(dgram_server_name, dgram_server_argv);
632
633 /*
634 * Running as a semi-resident server. Service requests. Terminate when we
635 * have serviced a sufficient number of requests, when no-one has been
636 * talking to us for a configurable amount of time, or when the master
637 * process terminated abnormally.
638 */
639 if (var_idle_limit > 0)
640 event_request_timer(dgram_server_timeout, (void *) 0, var_idle_limit);
641 for (fd = MASTER_LISTEN_FD; fd < MASTER_LISTEN_FD + socket_count; fd++) {
642 event_enable_read(fd, dgram_server_accept, CAST_INT_TO_VOID_PTR(fd));
643 close_on_exec(fd, CLOSE_ON_EXEC);
644 }
645 event_enable_read(MASTER_STATUS_FD, dgram_server_abort, (void *) 0);
646 close_on_exec(MASTER_STATUS_FD, CLOSE_ON_EXEC);
647 close_on_exec(MASTER_FLOW_READ, CLOSE_ON_EXEC);
648 close_on_exec(MASTER_FLOW_WRITE, CLOSE_ON_EXEC);
649 watchdog = watchdog_create(dgram_server_watchdog,
650 (WATCHDOG_FN) 0, (void *) 0);
651
652 /*
653 * The event loop, at last.
654 */
655 while (var_use_limit == 0 || use_count < var_use_limit) {
656 if (dgram_server_lock != 0) {
657 watchdog_stop(watchdog);
658 if (myflock(vstream_fileno(dgram_server_lock), INTERNAL_LOCK,
659 MYFLOCK_OP_EXCLUSIVE) < 0)
660 msg_fatal("select lock: %m");
661 }
662 watchdog_start(watchdog);
663 delay = loop ? loop(dgram_server_name, dgram_server_argv) : -1;
664 event_loop(delay);
665 }
666 dgram_server_exit();
667 }
668