4 * Citadel "system dependent" stuff.
5 * See copyright.txt for copyright information.
7 * Here's where we (hopefully) have most parts of the Citadel server that
8 * would need to be altered to run the server in a non-POSIX environment.
10 * If we ever port to a different platform and either have multiple
11 * variants of this file or simply load it up with #ifdefs.
22 #include <sys/types.h>
25 #include <sys/socket.h>
27 #include <sys/syslog.h>
29 #if TIME_WITH_SYS_TIME
30 # include <sys/time.h>
34 # include <sys/time.h>
41 #include <sys/resource.h>
42 #include <netinet/in.h>
43 #include <netinet/tcp.h>
44 #include <arpa/inet.h>
52 #include <libcitadel.h>
55 #include "sysdep_decls.h"
56 #include "citserver.h"
60 #include "housekeeping.h"
61 #include "modules/crypto/serv_crypto.h" /* Needed for init_ssl, client_write_ssl, client_read_ssl, destruct_ssl */
64 #ifdef HAVE_SYS_SELECT_H
65 #include <sys/select.h>
72 #include "ctdl_module.h"
75 #ifdef DEBUG_MEMORY_LEAKS
83 struct igheap *igheap = NULL;
87 citthread_key_t MyConKey; /* TSD key for MyContext() */
89 int verbosity = DEFAULT_VERBOSITY; /* Logging level */
91 struct CitContext masterCC;
92 time_t last_purge = 0; /* Last dead session purge */
93 int num_sessions = 0; /* Current number of sessions */
95 int syslog_facility = LOG_DAEMON;
96 int enable_syslog = 0;
100 * Create an interface to lprintf that follows the coding convention.
101 * This is here until such time as we have replaced all calls to lprintf with CtdlLogPrintf
104 void CtdlLogPrintf(enum LogLevel loglevel, const char *format, ...)
107 va_start(arg_ptr, format);
108 vlprintf(loglevel, format, arg_ptr);
114 * lprintf() ... Write logging information
116 void lprintf(enum LogLevel loglevel, const char *format, ...) {
118 va_start(arg_ptr, format);
119 vlprintf(loglevel, format, arg_ptr);
123 void vlprintf(enum LogLevel loglevel, const char *format, va_list arg_ptr)
125 char buf[SIZ], buf2[SIZ];
128 vsyslog((syslog_facility | loglevel), format, arg_ptr);
131 /* stderr output code */
132 if (enable_syslog || running_as_daemon) return;
134 /* if we run in forground and syslog is disabled, log to terminal */
135 if (loglevel <= verbosity) {
140 gettimeofday(&tv, NULL);
141 /* Promote to time_t; types differ on some OSes (like darwin) */
142 unixtime = tv.tv_sec;
143 localtime_r(&unixtime, &tim);
144 if (CC->cs_pid != 0) {
146 "%04d/%02d/%02d %2d:%02d:%02d.%06ld [%3d] ",
147 tim.tm_year + 1900, tim.tm_mon + 1,
148 tim.tm_mday, tim.tm_hour, tim.tm_min,
149 tim.tm_sec, (long)tv.tv_usec,
153 "%04d/%02d/%02d %2d:%02d:%02d.%06ld ",
154 tim.tm_year + 1900, tim.tm_mon + 1,
155 tim.tm_mday, tim.tm_hour, tim.tm_min,
156 tim.tm_sec, (long)tv.tv_usec);
158 vsnprintf(buf2, SIZ, format, arg_ptr);
160 fprintf(stderr, "%s%s", buf, buf2);
168 * Signal handler to shut down the server.
171 volatile int exit_signal = 0;
172 volatile int shutdown_and_halt = 0;
173 volatile int restart_server = 0;
174 volatile int running_as_daemon = 0;
176 static RETSIGTYPE signal_cleanup(int signum) {
177 CtdlLogPrintf(CTDL_DEBUG, "Caught signal %d; shutting down.\n", signum);
178 #ifdef THREADS_USESIGNALS
181 CtdlLogPrintf(CTDL_DEBUG, "Thread \"%s\" caught signal %d.\n", CT->name, signum);
186 exit_signal = signum;
192 * Some initialization stuff...
194 void init_sysdep(void) {
197 /* Avoid vulnerabilities related to FD_SETSIZE if we can. */
201 getrlimit(RLIMIT_NOFILE, &rl);
202 rl.rlim_cur = FD_SETSIZE;
203 rl.rlim_max = FD_SETSIZE;
204 setrlimit(RLIMIT_NOFILE, &rl);
208 /* If we've got OpenSSL, we're going to use it. */
214 * Set up a place to put thread-specific data.
215 * We only need a single pointer per thread - it points to the
216 * CitContext structure (in the ContextList linked list) of the
217 * session to which the calling thread is currently bound.
219 if (citthread_key_create(&MyConKey, NULL) != 0) {
220 CtdlLogPrintf(CTDL_CRIT, "Can't create TSD key: %s\n",
225 * The action for unexpected signals and exceptions should be to
226 * call signal_cleanup() to gracefully shut down the server.
229 sigaddset(&set, SIGINT);
230 sigaddset(&set, SIGQUIT);
231 sigaddset(&set, SIGHUP);
232 sigaddset(&set, SIGTERM);
233 // sigaddset(&set, SIGSEGV); commented out because
234 // sigaddset(&set, SIGILL); we want core dumps
235 // sigaddset(&set, SIGBUS);
236 sigprocmask(SIG_UNBLOCK, &set, NULL);
238 sigaddset(&set, SIGUSR1);
239 sigprocmask(SIG_BLOCK, &set, NULL);
241 signal(SIGINT, signal_cleanup);
242 signal(SIGQUIT, signal_cleanup);
243 signal(SIGHUP, signal_cleanup);
244 signal(SIGTERM, signal_cleanup);
245 // signal(SIGSEGV, signal_cleanup); commented out because
246 // signal(SIGILL, signal_cleanup); we want core dumps
247 // signal(SIGBUS, signal_cleanup);
250 * Do not shut down the server on broken pipe signals, otherwise the
251 * whole Citadel service would come down whenever a single client
254 signal(SIGPIPE, SIG_IGN);
261 * This is a generic function to set up a master socket for listening on
262 * a TCP port. The server shuts down if the bind fails.
265 int ig_tcp_server(char *ip_addr, int port_number, int queue_len, char **errormessage)
267 struct sockaddr_in sin;
269 int actual_queue_len;
271 actual_queue_len = queue_len;
272 if (actual_queue_len < 5) actual_queue_len = 5;
274 memset(&sin, 0, sizeof(sin));
275 sin.sin_family = AF_INET;
276 sin.sin_port = htons((u_short)port_number);
277 if (ip_addr == NULL) {
278 sin.sin_addr.s_addr = INADDR_ANY;
281 sin.sin_addr.s_addr = inet_addr(ip_addr);
284 if (sin.sin_addr.s_addr == !INADDR_ANY) {
285 sin.sin_addr.s_addr = INADDR_ANY;
288 s = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
291 *errormessage = (char*) malloc(SIZ + 1);
292 snprintf(*errormessage, SIZ,
293 "citserver: Can't create a socket: %s",
295 CtdlLogPrintf(CTDL_EMERG, "%s\n", *errormessage);
300 setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &i, sizeof(i));
302 if (bind(s, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
303 *errormessage = (char*) malloc(SIZ + 1);
304 snprintf(*errormessage, SIZ,
305 "citserver: Can't bind: %s",
307 CtdlLogPrintf(CTDL_EMERG, "%s\n", *errormessage);
312 /* set to nonblock - we need this for some obscure situations */
313 if (fcntl(s, F_SETFL, O_NONBLOCK) < 0) {
314 *errormessage = (char*) malloc(SIZ + 1);
315 snprintf(*errormessage, SIZ,
316 "citserver: Can't set socket to non-blocking: %s",
318 CtdlLogPrintf(CTDL_EMERG, "%s\n", *errormessage);
323 if (listen(s, actual_queue_len) < 0) {
324 *errormessage = (char*) malloc(SIZ + 1);
325 snprintf(*errormessage, SIZ,
326 "citserver: Can't listen: %s",
328 CtdlLogPrintf(CTDL_EMERG, "%s\n", *errormessage);
339 * Create a Unix domain socket and listen on it
341 int ig_uds_server(char *sockpath, int queue_len, char **errormessage)
343 struct sockaddr_un addr;
346 int actual_queue_len;
348 actual_queue_len = queue_len;
349 if (actual_queue_len < 5) actual_queue_len = 5;
351 i = unlink(sockpath);
352 if (i != 0) if (errno != ENOENT) {
353 *errormessage = (char*) malloc(SIZ + 1);
354 snprintf(*errormessage, SIZ, "citserver: can't unlink %s: %s",
355 sockpath, strerror(errno));
356 CtdlLogPrintf(CTDL_EMERG, "%s\n", *errormessage);
360 memset(&addr, 0, sizeof(addr));
361 addr.sun_family = AF_UNIX;
362 safestrncpy(addr.sun_path, sockpath, sizeof addr.sun_path);
364 s = socket(AF_UNIX, SOCK_STREAM, 0);
366 *errormessage = (char*) malloc(SIZ + 1);
367 snprintf(*errormessage, SIZ,
368 "citserver: Can't create a socket: %s",
370 CtdlLogPrintf(CTDL_EMERG, "%s\n", *errormessage);
374 if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
375 *errormessage = (char*) malloc(SIZ + 1);
376 snprintf(*errormessage, SIZ,
377 "citserver: Can't bind: %s",
379 CtdlLogPrintf(CTDL_EMERG, "%s\n", *errormessage);
383 /* set to nonblock - we need this for some obscure situations */
384 if (fcntl(s, F_SETFL, O_NONBLOCK) < 0) {
385 *errormessage = (char*) malloc(SIZ + 1);
386 snprintf(*errormessage, SIZ,
387 "citserver: Can't set socket to non-blocking: %s",
389 CtdlLogPrintf(CTDL_EMERG, "%s\n", *errormessage);
394 if (listen(s, actual_queue_len) < 0) {
395 *errormessage = (char*) malloc(SIZ + 1);
396 snprintf(*errormessage, SIZ,
397 "citserver: Can't listen: %s",
399 CtdlLogPrintf(CTDL_EMERG, "%s\n", *errormessage);
403 chmod(sockpath, S_ISGID|S_IRUSR|S_IWUSR|S_IXUSR|S_IRGRP|S_IWGRP|S_IXGRP|S_IROTH|S_IWOTH|S_IXOTH);
410 * Return a pointer to the CitContext structure bound to the thread which
411 * called this function. If there's no such binding (for example, if it's
412 * called by the housekeeper thread) then a generic 'master' CC is returned.
414 * This function is used *VERY* frequently and must be kept small.
416 struct CitContext *MyContext(void) {
418 register struct CitContext *c;
420 return ((c = (struct CitContext *) citthread_getspecific(MyConKey),
421 c == NULL) ? &masterCC : c
427 * Initialize a new context and place it in the list. The session number
428 * used to be the PID (which is why it's called cs_pid), but that was when we
429 * had one process per session. Now we just assign them sequentially, starting
430 * at 1 (don't change it to 0 because masterCC uses 0).
432 struct CitContext *CreateNewContext(void) {
433 struct CitContext *me;
434 static int next_pid = 0;
436 me = (struct CitContext *) malloc(sizeof(struct CitContext));
438 CtdlLogPrintf(CTDL_ALERT, "citserver: can't allocate memory!!\n");
441 memset(me, 0, sizeof(struct CitContext));
443 /* The new context will be created already in the CON_EXECUTING state
444 * in order to prevent another thread from grabbing it while it's
447 me->state = CON_EXECUTING;
449 * Generate a unique session number and insert this context into
452 begin_critical_section(S_SESSION_TABLE);
453 me->cs_pid = ++next_pid;
455 me->next = ContextList;
457 if (me->next != NULL) {
460 me->client_expires_at.tv_sec = config.c_sleeping;
462 end_critical_section(S_SESSION_TABLE);
468 * The following functions implement output buffering. If the kernel supplies
469 * native TCP buffering (Linux & *BSD), use that; otherwise, emulate it with
470 * user-space buffering.
474 # define HAVE_TCP_BUFFERING
477 # define HAVE_TCP_BUFFERING
478 # define TCP_CORK TCP_NOPUSH
480 #endif /* TCP_CORK */
481 #endif /* HAVE_DARWIN */
483 #ifdef HAVE_TCP_BUFFERING
484 static unsigned on = 1, off = 0;
485 void buffer_output(void) {
486 struct CitContext *ctx = MyContext();
487 setsockopt(ctx->client_socket, IPPROTO_TCP, TCP_CORK, &on, 4);
491 void unbuffer_output(void) {
492 struct CitContext *ctx = MyContext();
493 setsockopt(ctx->client_socket, IPPROTO_TCP, TCP_CORK, &off, 4);
497 void flush_output(void) {
498 struct CitContext *ctx = MyContext();
499 setsockopt(ctx->client_socket, IPPROTO_TCP, TCP_CORK, &off, 4);
500 setsockopt(ctx->client_socket, IPPROTO_TCP, TCP_CORK, &on, 4);
504 /* Stub functions for Darwin/OS X where TCP buffering isn't liked at all */
505 void buffer_output(void) {
508 void unbuffer_output(void) {
511 void flush_output(void) {
514 void buffer_output(void) {
515 if (CC->buffering == 0) {
518 CC->output_buffer = malloc(SIZ);
522 void flush_output(void) {
523 if (CC->buffering == 1) {
524 client_write(CC->output_buffer, CC->buffer_len);
529 void unbuffer_output(void) {
530 if (CC->buffering == 1) {
532 /* We don't call flush_output because we can't. */
533 client_write(CC->output_buffer, CC->buffer_len);
535 free(CC->output_buffer);
536 CC->output_buffer = NULL;
539 #endif /* HAVE_DARWIN */
540 #endif /* HAVE_TCP_BUFFERING */
545 * client_write() ... Send binary data to the client.
547 void client_write(char *buf, int nbytes)
549 int bytes_written = 0;
551 #ifndef HAVE_TCP_BUFFERING
552 int old_buffer_len = 0;
557 if (Ctx->redirect_buffer != NULL) {
558 if ((Ctx->redirect_len + nbytes + 2) >= Ctx->redirect_alloc) {
559 Ctx->redirect_alloc = (Ctx->redirect_alloc * 2) + nbytes;
560 Ctx->redirect_buffer = realloc(Ctx->redirect_buffer,
561 Ctx->redirect_alloc);
563 memcpy(&Ctx->redirect_buffer[Ctx->redirect_len], buf, nbytes);
564 Ctx->redirect_len += nbytes;
565 Ctx->redirect_buffer[Ctx->redirect_len] = 0;
569 #ifndef HAVE_TCP_BUFFERING
570 /* If we're buffering for later, do that now. */
571 if (Ctx->buffering) {
572 old_buffer_len = Ctx->buffer_len;
573 Ctx->buffer_len += nbytes;
574 Ctx->output_buffer = realloc(Ctx->output_buffer, Ctx->buffer_len);
575 memcpy(&Ctx->output_buffer[old_buffer_len], buf, nbytes);
580 /* Ok, at this point we're not buffering. Go ahead and write. */
583 if (Ctx->redirect_ssl) {
584 client_write_ssl(buf, nbytes);
589 while (bytes_written < nbytes) {
590 retval = write(Ctx->client_socket, &buf[bytes_written],
591 nbytes - bytes_written);
593 CtdlLogPrintf(CTDL_ERR,
594 "client_write(%d bytes) failed: %s (%d)\n",
595 nbytes - bytes_written,
596 strerror(errno), errno);
598 // CtdlLogPrintf(CTDL_DEBUG, "Tried to send: %s", &buf[bytes_written]);
602 bytes_written = bytes_written + retval;
608 * cprintf() ... Send formatted printable data to the client. It is
609 * implemented in terms of client_write() but remains in
610 * sysdep.c in case we port to somewhere without va_args...
612 void cprintf(const char *format, ...) {
616 va_start(arg_ptr, format);
617 if (vsnprintf(buf, sizeof buf, format, arg_ptr) == -1)
618 buf[sizeof buf - 2] = '\n';
619 client_write(buf, strlen(buf));
625 * Read data from the client socket.
627 * 1 Requested number of bytes has been read.
628 * 0 Request timed out.
629 * -1 The socket is broken.
630 * If the socket breaks, the session will be terminated.
632 int client_read_to(char *buf, int bytes, int timeout)
641 if (CC->redirect_ssl) {
642 return (client_read_ssl(buf, bytes, timeout));
646 fd = CC->client_socket;
653 retval = select( (fd)+1,
654 &rfds, NULL, NULL, &tv);
656 if (FD_ISSET(fd, &rfds) == 0) {
660 rlen = read(fd, &buf[len], bytes-len);
662 /* The socket has been disconnected! */
672 * Read data from the client socket with default timeout.
673 * (This is implemented in terms of client_read_to() and could be
674 * justifiably moved out of sysdep.c)
676 INLINE int client_read(char *buf, int bytes)
678 return(client_read_to(buf, bytes, config.c_sleeping));
683 * client_getln() ... Get a LF-terminated line of text from the client.
684 * (This is implemented in terms of client_read() and could be
685 * justifiably moved out of sysdep.c)
687 int client_getln(char *buf, int bufsize)
691 /* Read one character at a time.
694 retval = client_read(&buf[i], 1);
695 if (retval != 1 || buf[i] == '\n' || i == (bufsize-1))
699 /* If we got a long line, discard characters until the newline.
701 if (i == (bufsize-1))
702 while (buf[i] != '\n' && retval == 1)
703 retval = client_read(&buf[i], 1);
705 /* Strip the trailing LF, and the trailing CR if present.
709 && ( (buf[i - 1]==13)
710 || ( buf[i - 1]==10)) ) {
714 if (retval < 0) safestrncpy(&buf[i], "000", bufsize - i);
720 * Cleanup any contexts that are left lying around
722 void context_cleanup(void)
724 struct CitContext *ptr = NULL;
725 struct CitContext *rem = NULL;
728 * Clean up the contexts.
729 * There are no threads so no critical_section stuff is needed.
733 /* We need to update the ContextList because some modules may want to itterate it
734 * Question is should we NULL it before iterating here or should we just keep updating it
735 * as we remove items?
737 * Answer is to NULL it first to prevent modules from doing any actions on the list at all
741 /* Remove the session from the active list */
745 lprintf(CTDL_DEBUG, "Purging session %d\n", ptr->cs_pid);
754 void close_masters (void)
756 struct ServiceFunctionHook *serviceptr;
759 * close all protocol master sockets
761 for (serviceptr = ServiceHookTable; serviceptr != NULL;
762 serviceptr = serviceptr->next ) {
764 if (serviceptr->tcp_port > 0)
766 CtdlLogPrintf(CTDL_INFO, "Closing listener on port %d\n",
767 serviceptr->tcp_port);
768 serviceptr->tcp_port = 0;
771 if (serviceptr->sockpath != NULL)
772 CtdlLogPrintf(CTDL_INFO, "Closing listener on '%s'\n",
773 serviceptr->sockpath);
775 close(serviceptr->msock);
776 /* If it's a Unix domain socket, remove the file. */
777 if (serviceptr->sockpath != NULL) {
778 unlink(serviceptr->sockpath);
779 serviceptr->sockpath = NULL;
786 * The system-dependent part of master_cleanup() - close the master socket.
788 void sysdep_master_cleanup(void) {
797 CtdlDestroyProtoHooks();
798 CtdlDestroyDeleteHooks();
799 CtdlDestroyXmsgHooks();
800 CtdlDestroyNetprocHooks();
801 CtdlDestroyUserHooks();
802 CtdlDestroyMessageHook();
803 CtdlDestroyCleanupHooks();
804 CtdlDestroyFixedOutputHooks();
805 CtdlDestroySessionHooks();
806 CtdlDestroyServiceHook();
807 CtdlDestroyRoomHooks();
808 CtdlDestroyDirectoryServiceFuncs();
809 #ifdef HAVE_BACKTRACE
817 * Terminate another session.
818 * (This could justifiably be moved out of sysdep.c because it
819 * no longer does anything that is system-dependent.)
821 void kill_session(int session_to_kill) {
822 struct CitContext *ptr;
824 begin_critical_section(S_SESSION_TABLE);
825 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
826 if (ptr->cs_pid == session_to_kill) {
830 end_critical_section(S_SESSION_TABLE);
834 void graceful_shutdown(int signum) {
835 kill(current_child, signum);
836 unlink(file_pid_file);
842 * Start running as a daemon.
844 void start_daemon(int unused) {
852 /* Close stdin/stdout/stderr and replace them with /dev/null.
853 * We don't just call close() because we don't want these fd's
854 * to be reused for other files.
863 signal(SIGHUP, SIG_IGN);
864 signal(SIGINT, SIG_IGN);
865 signal(SIGQUIT, SIG_IGN);
869 freopen("/dev/null", "r", stdin);
870 freopen("/dev/null", "w", stdout);
871 freopen("/dev/null", "w", stderr);
874 current_child = fork();
876 signal(SIGTERM, graceful_shutdown);
878 if (current_child < 0) {
883 else if (current_child == 0) {
884 return; /* continue starting citadel. */
888 fp = fopen(file_pid_file, "w");
890 fprintf(fp, ""F_PID_T"\n", getpid());
893 waitpid(current_child, &status, 0);
898 /* Did the main process exit with an actual exit code? */
899 if (WIFEXITED(status)) {
901 /* Exit code 0 means the watcher should exit */
902 if (WEXITSTATUS(status) == 0) {
906 /* Exit code 101-109 means the watcher should exit */
907 else if ( (WEXITSTATUS(status) >= 101) && (WEXITSTATUS(status) <= 109) ) {
911 /* Any other exit code means we should restart. */
917 /* Any other type of termination (signals, etc.) should also restart. */
922 } while (do_restart);
924 unlink(file_pid_file);
925 exit(WEXITSTATUS(status));
931 * Generic routine to convert a login name to a full name (gecos)
932 * Returns nonzero if a conversion took place
934 int convert_login(char NameToConvert[]) {
938 pw = getpwnam(NameToConvert);
943 strcpy(NameToConvert, pw->pw_gecos);
944 for (a=0; a<strlen(NameToConvert); ++a) {
945 if (NameToConvert[a] == ',') NameToConvert[a] = 0;
952 * Purge all sessions which have the 'kill_me' flag set.
953 * This function has code to prevent it from running more than once every
954 * few seconds, because running it after every single unbind would waste a lot
955 * of CPU time and keep the context list locked too much. To force it to run
956 * anyway, set "force" to nonzero.
958 void dead_session_purge(int force) {
959 struct CitContext *ptr, *ptr2; /* general-purpose utility pointer */
960 struct CitContext *rem = NULL; /* list of sessions to be destroyed */
963 if ( (time(NULL) - last_purge) < 5 ) {
964 return; /* Too soon, go away */
969 if (try_critical_section(S_SESSION_TABLE))
977 if ( (ptr2->state == CON_IDLE) && (ptr2->kill_me) ) {
978 /* Remove the session from the active list */
980 ptr2->prev->next = ptr2->next;
983 ContextList = ptr2->next;
986 ptr2->next->prev = ptr2->prev;
990 /* And put it on our to-be-destroyed list */
995 end_critical_section(S_SESSION_TABLE);
997 /* Now that we no longer have the session list locked, we can take
998 * our time and destroy any sessions on the to-be-killed list, which
999 * is allocated privately on this thread's stack.
1001 while (rem != NULL) {
1002 CtdlLogPrintf(CTDL_DEBUG, "Purging session %d\n", rem->cs_pid);
1015 * masterCC is the context we use when not attached to a session. This
1016 * function initializes it.
1018 void InitializeMasterCC(void) {
1019 memset(&masterCC, 0, sizeof(struct CitContext));
1020 masterCC.internal_pgm = 1;
1021 masterCC.cs_pid = 0;
1030 * Bind a thread to a context. (It's inline merely to speed things up.)
1032 INLINE void become_session(struct CitContext *which_con) {
1033 citthread_setspecific(MyConKey, (void *)which_con );
1039 * This loop just keeps going and going and going...
1043 * This current implimentation of worker_thread creates a bottle neck in several situations
1044 * The first thing to remember is that a single thread can handle more than one connection at a time.
1045 * More threads mean less memory for the system to run in.
1046 * So for efficiency we want every thread to be doing something useful or waiting in the main loop for
1047 * something to happen anywhere.
1048 * This current implimentation requires worker threads to wait in other locations, after it has
1049 * been committed to a single connection which is very wasteful.
1050 * As an extreme case consider this:
1051 * A slow client connects and this slow client sends only one character each second.
1052 * With this current implimentation a single worker thread is dispatched to handle that connection
1053 * until such times as the client timeout expires, an error occurs on the socket or the client
1054 * completes its transmission.
1055 * THIS IS VERY BAD since that thread could have handled a read from many more clients in each one
1056 * second interval between chars.
1058 * It is my intention to re-write this code and the associated client_getln, client_read functions
1059 * to allow any thread to read data on behalf of any connection (context).
1060 * To do this I intend to have this main loop read chars into a buffer stored in the context.
1061 * Once the correct criteria for a full buffer is met then we will dispatch a thread to
1063 * This worker thread loop also needs to be able to handle binary data.
1066 void *worker_thread(void *arg) {
1069 struct CitContext *ptr;
1070 struct CitContext *bind_me = NULL;
1073 struct CitContext *con= NULL; /* Temporary context pointer */
1074 struct ServiceFunctionHook *serviceptr;
1075 int ssock; /* Descriptor for client socket */
1077 int force_purge = 0;
1081 while (!CtdlThreadCheckStop()) {
1083 /* make doubly sure we're not holding any stale db handles
1084 * which might cause a deadlock.
1086 cdb_check_handles();
1087 do_select: force_purge = 0;
1088 bind_me = NULL; /* Which session shall we handle? */
1090 /* Initialize the fdset. */
1094 begin_critical_section(S_SESSION_TABLE);
1095 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
1096 if (ptr->state == CON_IDLE) {
1097 FD_SET(ptr->client_socket, &readfds);
1098 if (ptr->client_socket > highest)
1099 highest = ptr->client_socket;
1101 if ((bind_me == NULL) && (ptr->state == CON_READY)) {
1103 ptr->state = CON_EXECUTING;
1106 end_critical_section(S_SESSION_TABLE);
1112 /* If we got this far, it means that there are no sessions
1113 * which a previous thread marked for attention, so we go
1114 * ahead and get ready to select().
1117 /* First, add the various master sockets to the fdset. */
1118 for (serviceptr = ServiceHookTable; serviceptr != NULL;
1119 serviceptr = serviceptr->next ) {
1120 m = serviceptr->msock;
1121 FD_SET(m, &readfds);
1127 if (!CtdlThreadCheckStop()) {
1128 tv.tv_sec = 1; /* wake up every second if no input */
1130 retval = CtdlThreadSelect(highest + 1, &readfds, NULL, NULL, &tv);
1133 if (CtdlThreadCheckStop()) return(NULL);
1135 /* Now figure out who made this select() unblock.
1136 * First, check for an error or exit condition.
1139 if (errno == EBADF) {
1140 CtdlLogPrintf(CTDL_NOTICE, "select() failed: (%s)\n",
1144 if (errno != EINTR) {
1145 CtdlLogPrintf(CTDL_EMERG, "Exiting (%s)\n", strerror(errno));
1146 CtdlThreadStopAll();
1147 } else if (!CtdlThreadCheckStop()) {
1148 CtdlLogPrintf(CTDL_DEBUG, "Interrupted select.\n");
1152 else if(retval == 0) {
1155 /* Next, check to see if it's a new client connecting
1156 * on a master socket.
1158 else for (serviceptr = ServiceHookTable; serviceptr != NULL;
1159 serviceptr = serviceptr->next ) {
1161 if (FD_ISSET(serviceptr->msock, &readfds)) {
1162 ssock = accept(serviceptr->msock, NULL, 0);
1164 CtdlLogPrintf(CTDL_DEBUG,
1165 "New client socket %d\n",
1168 /* The master socket is non-blocking but the client
1169 * sockets need to be blocking, otherwise certain
1170 * operations barf on FreeBSD. Not a fatal error.
1172 if (fcntl(ssock, F_SETFL, 0) < 0) {
1173 CtdlLogPrintf(CTDL_EMERG,
1174 "citserver: Can't set socket to blocking: %s\n",
1178 /* New context will be created already
1179 * set up in the CON_EXECUTING state.
1181 con = CreateNewContext();
1183 /* Assign our new socket number to it. */
1184 con->client_socket = ssock;
1185 con->h_command_function =
1186 serviceptr->h_command_function;
1187 con->h_async_function =
1188 serviceptr->h_async_function;
1190 serviceptr->ServiceName;
1192 /* Determine whether it's a local socket */
1193 if (serviceptr->sockpath != NULL)
1194 con->is_local_socket = 1;
1196 /* Set the SO_REUSEADDR socket option */
1198 setsockopt(ssock, SOL_SOCKET,
1202 become_session(con);
1204 serviceptr->h_greeting_function();
1205 become_session(NULL);
1206 con->state = CON_IDLE;
1212 /* It must be a client socket. Find a context that has data
1213 * waiting on its socket *and* is in the CON_IDLE state. Any
1214 * active sockets other than our chosen one are marked as
1215 * CON_READY so the next thread that comes around can just bind
1216 * to one without having to select() again.
1218 begin_critical_section(S_SESSION_TABLE);
1219 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
1220 if ( (FD_ISSET(ptr->client_socket, &readfds))
1221 && (ptr->state != CON_EXECUTING) ) {
1222 ptr->input_waiting = 1;
1224 bind_me = ptr; /* I choose you! */
1225 bind_me->state = CON_EXECUTING;
1228 ptr->state = CON_READY;
1232 end_critical_section(S_SESSION_TABLE);
1235 /* We're bound to a session */
1236 if (bind_me != NULL) {
1237 become_session(bind_me);
1239 /* If the client has sent a command, execute it. */
1240 if (CC->input_waiting) {
1241 CC->h_command_function();
1242 CC->input_waiting = 0;
1245 /* If there are asynchronous messages waiting and the
1246 * client supports it, do those now */
1247 if ((CC->is_async) && (CC->async_waiting)
1248 && (CC->h_async_function != NULL)) {
1249 CC->h_async_function();
1250 CC->async_waiting = 0;
1253 force_purge = CC->kill_me;
1254 become_session(NULL);
1255 bind_me->state = CON_IDLE;
1258 dead_session_purge(force_purge);
1260 /* If control reaches this point, the server is shutting down */
1269 * Translate text facility name to syslog.h defined value.
1271 int SyslogFacility(char *name)
1280 { LOG_KERN, "kern" },
1281 { LOG_USER, "user" },
1282 { LOG_MAIL, "mail" },
1283 { LOG_DAEMON, "daemon" },
1284 { LOG_AUTH, "auth" },
1285 { LOG_SYSLOG, "syslog" },
1287 { LOG_NEWS, "news" },
1288 { LOG_UUCP, "uucp" },
1289 { LOG_LOCAL0, "local0" },
1290 { LOG_LOCAL1, "local1" },
1291 { LOG_LOCAL2, "local2" },
1292 { LOG_LOCAL3, "local3" },
1293 { LOG_LOCAL4, "local4" },
1294 { LOG_LOCAL5, "local5" },
1295 { LOG_LOCAL6, "local6" },
1296 { LOG_LOCAL7, "local7" },
1299 for(i = 0; facTbl[i].name != NULL; i++) {
1300 if(!strcasecmp(name, facTbl[i].name))
1301 return facTbl[i].facility;
1308 /********** MEM CHEQQER ***********/
1310 #ifdef DEBUG_MEMORY_LEAKS
1317 void *tracked_malloc(size_t size, char *file, int line) {
1318 struct igheap *thisheap;
1321 block = malloc(size);
1322 if (block == NULL) return(block);
1324 thisheap = malloc(sizeof(struct igheap));
1325 if (thisheap == NULL) {
1330 thisheap->block = block;
1331 strcpy(thisheap->file, file);
1332 thisheap->line = line;
1334 begin_critical_section(S_DEBUGMEMLEAKS);
1335 thisheap->next = igheap;
1337 end_critical_section(S_DEBUGMEMLEAKS);
1343 void *tracked_realloc(void *ptr, size_t size, char *file, int line) {
1344 struct igheap *thisheap;
1347 block = realloc(ptr, size);
1348 if (block == NULL) return(block);
1350 thisheap = malloc(sizeof(struct igheap));
1351 if (thisheap == NULL) {
1356 thisheap->block = block;
1357 strcpy(thisheap->file, file);
1358 thisheap->line = line;
1360 begin_critical_section(S_DEBUGMEMLEAKS);
1361 thisheap->next = igheap;
1363 end_critical_section(S_DEBUGMEMLEAKS);
1370 void tracked_free(void *ptr) {
1371 struct igheap *thisheap;
1372 struct igheap *trash;
1376 if (igheap == NULL) return;
1377 begin_critical_section(S_DEBUGMEMLEAKS);
1378 for (thisheap = igheap; thisheap != NULL; thisheap = thisheap->next) {
1379 if (thisheap->next != NULL) {
1380 if (thisheap->next->block == ptr) {
1381 trash = thisheap->next;
1382 thisheap->next = thisheap->next->next;
1387 if (igheap->block == ptr) {
1389 igheap = igheap->next;
1392 end_critical_section(S_DEBUGMEMLEAKS);
1395 char *tracked_strdup(const char *s, char *file, int line) {
1398 if (s == NULL) return(NULL);
1399 ptr = tracked_malloc(strlen(s) + 1, file, line);
1400 if (ptr == NULL) return(NULL);
1401 strncpy(ptr, s, strlen(s));
1405 void dump_heap(void) {
1406 struct igheap *thisheap;
1408 for (thisheap = igheap; thisheap != NULL; thisheap = thisheap->next) {
1409 CtdlLogPrintf(CTDL_CRIT, "UNFREED: %30s : %d\n",
1410 thisheap->file, thisheap->line);
1414 #endif /* DEBUG_MEMORY_LEAKS */