4 * Citadel/UX "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.
23 #include <sys/types.h>
26 #include <sys/socket.h>
28 #if TIME_WITH_SYS_TIME
29 # include <sys/time.h>
33 # include <sys/time.h>
40 #include <netinet/in.h>
57 #include "sysdep_decls.h"
58 #include "citserver.h"
62 #include "housekeeping.h"
63 #include "dynloader.h"
66 #ifdef HAVE_SYS_SELECT_H
67 #include <sys/select.h>
74 #ifdef DEBUG_MEMORY_LEAKS
75 struct TheHeap *heap = NULL;
78 pthread_mutex_t Critters[MAX_SEMAPHORES]; /* Things needing locking */
79 pthread_key_t MyConKey; /* TSD key for MyContext() */
81 int verbosity = DEFAULT_VERBOSITY; /* Logging level */
83 struct CitContext masterCC;
84 int rescan[2]; /* The Rescan Pipe */
85 time_t last_purge = 0; /* Last dead session purge */
86 static int num_threads = 0; /* Current number of threads */
87 int num_sessions = 0; /* Current number of sessions */
89 fd_set masterfds; /* Master sockets etc. */
92 static pthread_t initial_thread; /* tid for main() thread */
96 * lprintf() ... Write logging information
98 * Note: the variable "buf" below needs to be large enough to handle any
99 * log data sent through this function. BE CAREFUL!
101 void lprintf(int loglevel, const char *format, ...) {
105 va_start(arg_ptr, format);
106 vsprintf(buf, format, arg_ptr);
109 if (loglevel <= verbosity) {
113 gettimeofday(&tv, NULL);
114 tim = localtime(&(tv.tv_sec));
116 * Log provides millisecond accuracy. If you need
117 * microsecond accuracy and your OS supports it, change
118 * %03ld to %06ld and remove " / 1000" after tv.tv_usec.
120 fprintf(stderr, "%04d/%02d/%02d %2d:%02d:%02d.%03ld %s",
121 tim->tm_year + 1900, tim->tm_mon + 1, tim->tm_mday,
122 tim->tm_hour, tim->tm_min, tim->tm_sec,
123 tv.tv_usec / 1000, buf);
127 PerformLogHooks(loglevel, buf);
132 #ifdef DEBUG_MEMORY_LEAKS
133 void *tracked_malloc(size_t tsize, char *tfile, int tline) {
135 struct TheHeap *hptr;
139 lprintf(3, "DANGER! mallok(%d) at %s:%d failed!\n",
140 tsize, tfile, tline);
144 hptr = (struct TheHeap *) malloc(sizeof(struct TheHeap));
145 strcpy(hptr->h_file, tfile);
146 hptr->h_line = tline;
153 char *tracked_strdup(const char *orig, char *tfile, int tline) {
156 s = tracked_malloc( (strlen(orig)+1), tfile, tline);
157 if (s == NULL) return NULL;
163 void tracked_free(void *ptr) {
164 struct TheHeap *hptr, *freeme;
166 if (heap->h_ptr == ptr) {
172 for (hptr=heap; hptr->next!=NULL; hptr=hptr->next) {
173 if (hptr->next->h_ptr == ptr) {
175 hptr->next = hptr->next->next;
184 void *tracked_realloc(void *ptr, size_t size) {
186 struct TheHeap *hptr;
188 newptr = realloc(ptr, size);
190 for (hptr=heap; hptr!=NULL; hptr=hptr->next) {
191 if (hptr->h_ptr == ptr) hptr->h_ptr = newptr;
198 void dump_tracked() {
199 struct TheHeap *hptr;
201 cprintf("%d Here's what's allocated...\n", LISTING_FOLLOWS);
202 for (hptr=heap; hptr!=NULL; hptr=hptr->next) {
203 cprintf("%20s %5d\n",
204 hptr->h_file, hptr->h_line);
216 * We used to use master_cleanup() as a signal handler to shut down the server.
217 * however, master_cleanup() and the functions it calls do some things that
218 * aren't such a good idea to do from a signal handler: acquiring mutexes,
219 * playing with signal masks on BSDI systems, etc. so instead we install the
220 * following signal handler to set a global variable to inform the main loop
221 * that it's time to call master_cleanup() and exit.
224 volatile int time_to_die = 0;
226 static RETSIGTYPE signal_cleanup(int signum) {
232 * Some initialization stuff...
234 void init_sysdep(void) {
237 /* Set up a bunch of semaphores to be used for critical sections */
238 for (a=0; a<MAX_SEMAPHORES; ++a) {
239 pthread_mutex_init(&Critters[a], NULL);
243 * Set up a place to put thread-specific data.
244 * We only need a single pointer per thread - it points to the
245 * CitContext structure (in the ContextList linked list) of the
246 * session to which the calling thread is currently bound.
248 if (pthread_key_create(&MyConKey, NULL) != 0) {
249 lprintf(1, "Can't create TSD key!! %s\n", strerror(errno));
253 * The action for unexpected signals and exceptions should be to
254 * call signal_cleanup() to gracefully shut down the server.
256 signal(SIGINT, signal_cleanup);
257 signal(SIGQUIT, signal_cleanup);
258 signal(SIGHUP, signal_cleanup);
259 signal(SIGTERM, signal_cleanup);
262 * Do not shut down the server on broken pipe signals, otherwise the
263 * whole Citadel service would come down whenever a single client
266 signal(SIGPIPE, SIG_IGN);
271 * Obtain a semaphore lock to begin a critical section.
273 void begin_critical_section(int which_one)
275 /* lprintf(9, "begin_critical_section(%d)\n", which_one); */
276 /* ensure nobody ever tries to do a critical section within a
277 transaction; this could lead to deadlock. */
279 pthread_mutex_lock(&Critters[which_one]);
283 * Release a semaphore lock to end a critical section.
285 void end_critical_section(int which_one)
287 /* lprintf(9, "end_critical_section(%d)\n", which_one); */
288 pthread_mutex_unlock(&Critters[which_one]);
294 * This is a generic function to set up a master socket for listening on
295 * a TCP port. The server shuts down if the bind fails.
298 int ig_tcp_server(int port_number, int queue_len)
300 struct sockaddr_in sin;
302 int actual_queue_len;
304 actual_queue_len = queue_len;
305 if (actual_queue_len < 5) actual_queue_len = 5;
307 memset(&sin, 0, sizeof(sin));
308 sin.sin_family = AF_INET;
309 sin.sin_addr.s_addr = INADDR_ANY;
310 sin.sin_port = htons((u_short)port_number);
312 s = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
315 lprintf(1, "citserver: Can't create a socket: %s\n",
321 setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &i, sizeof(i));
323 if (bind(s, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
324 lprintf(1, "citserver: Can't bind: %s\n",
330 if (listen(s, actual_queue_len) < 0) {
331 lprintf(1, "citserver: Can't listen: %s\n", strerror(errno));
342 * Create a Unix domain socket and listen on it
344 int ig_uds_server(char *sockpath, int queue_len)
346 struct sockaddr_un addr;
349 int actual_queue_len;
351 actual_queue_len = queue_len;
352 if (actual_queue_len < 5) actual_queue_len = 5;
354 i = unlink(sockpath);
355 if (i != 0) if (errno != ENOENT) {
356 lprintf(1, "citserver: can't unlink %s: %s\n",
357 sockpath, strerror(errno));
361 memset(&addr, 0, sizeof(addr));
362 addr.sun_family = AF_UNIX;
363 safestrncpy(addr.sun_path, sockpath, sizeof addr.sun_path);
365 s = socket(AF_UNIX, SOCK_STREAM, 0);
367 lprintf(1, "citserver: Can't create a socket: %s\n",
372 if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
373 lprintf(1, "citserver: Can't bind: %s\n",
378 if (listen(s, actual_queue_len) < 0) {
379 lprintf(1, "citserver: Can't listen: %s\n", strerror(errno));
383 chmod(sockpath, 0777);
390 * Return a pointer to the CitContext structure bound to the thread which
391 * called this function. If there's no such binding (for example, if it's
392 * called by the housekeeper thread) then a generic 'master' CC is returned.
394 struct CitContext *MyContext(void) {
395 struct CitContext *retCC;
396 retCC = (struct CitContext *) pthread_getspecific(MyConKey);
397 if (retCC == NULL) retCC = &masterCC;
403 * Initialize a new context and place it in the list. The session number
404 * used to be the PID (which is why it's called cs_pid), but that was when we
405 * had one process per session. Now we just assign them sequentially, starting
406 * at 1 (don't change it to 0 because masterCC uses 0) and re-using them when
407 * sessions terminate.
409 struct CitContext *CreateNewContext(void) {
410 struct CitContext *me, *ptr;
414 me = (struct CitContext *) mallok(sizeof(struct CitContext));
416 lprintf(1, "citserver: can't allocate memory!!\n");
419 memset(me, 0, sizeof(struct CitContext));
421 /* The new context will be created already in the CON_EXECUTING state
422 * in order to prevent another thread from grabbing it while it's
425 me->state = CON_EXECUTING;
427 begin_critical_section(S_SESSION_TABLE);
429 /* obtain a unique session number */
432 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
433 if (ptr->cs_pid == num) {
438 } while (startover == 1);
441 me->next = ContextList;
445 end_critical_section(S_SESSION_TABLE);
452 * client_write() ... Send binary data to the client.
454 void client_write(char *buf, int nbytes)
456 int bytes_written = 0;
461 if (CC->redirect_fp != NULL) {
462 fwrite(buf, nbytes, 1, CC->redirect_fp);
466 if (CC->redirect_sock > 0) {
467 sock = CC->redirect_sock; /* and continue below... */
470 sock = CC->client_socket;
473 while (bytes_written < nbytes) {
474 retval = write(sock, &buf[bytes_written],
475 nbytes - bytes_written);
477 lprintf(2, "client_write() failed: %s\n",
479 if (sock == CC->client_socket) CC->kill_me = 1;
482 bytes_written = bytes_written + retval;
488 * cprintf() ... Send formatted printable data to the client. It is
489 * implemented in terms of client_write() but remains in
490 * sysdep.c in case we port to somewhere without va_args...
492 void cprintf(const char *format, ...) {
496 va_start(arg_ptr, format);
497 if (vsnprintf(buf, sizeof buf, format, arg_ptr) == -1)
498 buf[sizeof buf - 2] = '\n';
499 client_write(buf, strlen(buf));
505 * Read data from the client socket.
507 * 1 Requested number of bytes has been read.
508 * 0 Request timed out.
509 * -1 The socket is broken.
510 * If the socket breaks, the session will be terminated.
512 int client_read_to(char *buf, int bytes, int timeout)
522 FD_SET(CC->client_socket, &rfds);
526 retval = select( (CC->client_socket)+1,
527 &rfds, NULL, NULL, &tv);
529 if (FD_ISSET(CC->client_socket, &rfds) == 0) {
533 rlen = read(CC->client_socket, &buf[len], bytes-len);
535 lprintf(2, "client_read() failed: %s\n",
546 * Read data from the client socket with default timeout.
547 * (This is implemented in terms of client_read_to() and could be
548 * justifiably moved out of sysdep.c)
550 int client_read(char *buf, int bytes)
552 return(client_read_to(buf, bytes, config.c_sleeping));
557 * client_gets() ... Get a LF-terminated line of text from the client.
558 * (This is implemented in terms of client_read() and could be
559 * justifiably moved out of sysdep.c)
561 int client_gets(char *buf)
565 /* Read one character at a time.
568 retval = client_read(&buf[i], 1);
569 if (retval != 1 || buf[i] == '\n' || i == (SIZ-1))
573 /* If we got a long line, discard characters until the newline.
576 while (buf[i] != '\n' && retval == 1)
577 retval = client_read(&buf[i], 1);
579 /* Strip the trailing newline and any trailing nonprintables (cr's)
582 while ((strlen(buf)>0)&&(!isprint(buf[strlen(buf)-1])))
583 buf[strlen(buf)-1] = 0;
584 if (retval < 0) strcpy(buf, "000");
591 * The system-dependent part of master_cleanup() - close the master socket.
593 void sysdep_master_cleanup(void) {
594 struct ServiceFunctionHook *serviceptr;
597 * close all protocol master sockets
599 for (serviceptr = ServiceHookTable; serviceptr != NULL;
600 serviceptr = serviceptr->next ) {
602 if (serviceptr->tcp_port > 0)
603 lprintf(3, "Closing listener on port %d\n",
604 serviceptr->tcp_port);
606 if (serviceptr->sockpath != NULL)
607 lprintf(3, "Closing listener on '%s'\n",
608 serviceptr->sockpath);
610 close(serviceptr->msock);
612 /* If it's a Unix domain socket, remove the file. */
613 if (serviceptr->sockpath != NULL) {
614 unlink(serviceptr->sockpath);
621 * Terminate another session.
622 * (This could justifiably be moved out of sysdep.c because it
623 * no longer does anything that is system-dependent.)
625 void kill_session(int session_to_kill) {
626 struct CitContext *ptr;
628 begin_critical_section(S_SESSION_TABLE);
629 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
630 if (ptr->cs_pid == session_to_kill) {
634 end_critical_section(S_SESSION_TABLE);
641 * Start running as a daemon. Only close stdio if do_close_stdio is set.
643 void start_daemon(int do_close_stdio) {
644 if (do_close_stdio) {
649 signal(SIGHUP,SIG_IGN);
650 signal(SIGINT,SIG_IGN);
651 signal(SIGQUIT,SIG_IGN);
652 if (fork()!=0) exit(0);
658 * Tie in to the 'netsetup' program.
660 * (We're going to hope that netsetup never feeds more than 4096 bytes back.)
662 void cmd_nset(char *cmdbuf)
669 char netsetup_args[3][SIZ];
671 if (CC->usersupp.axlevel < 6) {
672 cprintf("%d Higher access required.\n",
673 ERROR + HIGHER_ACCESS_REQUIRED);
677 for (a=1; a<=3; ++a) {
678 if (num_parms(cmdbuf) >= a) {
679 extract(netsetup_args[a-1], cmdbuf, a-1);
680 for (b=0; b<strlen(netsetup_args[a-1]); ++b) {
681 if (netsetup_args[a-1][b] == 34) {
682 netsetup_args[a-1][b] = '_';
687 netsetup_args[a-1][0] = 0;
691 sprintf(fbuf, "./netsetup \"%s\" \"%s\" \"%s\" </dev/null 2>&1",
692 netsetup_args[0], netsetup_args[1], netsetup_args[2]);
693 netsetup = popen(fbuf, "r");
694 if (netsetup == NULL) {
695 cprintf("%d %s\n", ERROR, strerror(errno));
700 while (ch = getc(netsetup), (ch > 0)) {
701 fbuf[strlen(fbuf)+1] = 0;
702 fbuf[strlen(fbuf)] = ch;
705 retcode = pclose(netsetup);
708 for (a=0; a<strlen(fbuf); ++a) {
709 if (fbuf[a] < 32) fbuf[a] = 32;
712 cprintf("%d %s\n", ERROR, fbuf);
716 cprintf("%d Command succeeded. Output follows:\n", LISTING_FOLLOWS);
718 if (fbuf[strlen(fbuf)-1] != 10) cprintf("\n");
725 * Generic routine to convert a login name to a full name (gecos)
726 * Returns nonzero if a conversion took place
728 int convert_login(char NameToConvert[]) {
732 pw = getpwnam(NameToConvert);
737 strcpy(NameToConvert, pw->pw_gecos);
738 for (a=0; a<strlen(NameToConvert); ++a) {
739 if (NameToConvert[a] == ',') NameToConvert[a] = 0;
745 static struct worker_node {
747 struct worker_node *next;
748 } *worker_list = NULL;
752 * create a worker thread. this function must always be called from within
753 * an S_WORKER_LIST critical section!
755 static void create_worker(void) {
757 struct worker_node *n = mallok(sizeof *n);
760 lprintf(1, "can't allocate worker_node, exiting\n");
765 if ((ret = pthread_create(&n->tid, NULL, worker_thread, NULL) != 0))
768 lprintf(1, "Can't create worker thread: %s\n",
772 n->next = worker_list;
779 * Purge all sessions which have the 'kill_me' flag set.
780 * This function has code to prevent it from running more than once every
781 * few seconds, because running it after every single unbind would waste a lot
782 * of CPU time and keep the context list locked too much.
784 * After that's done, we raise or lower the size of the worker thread pool
785 * if such an action is appropriate.
787 void dead_session_purge(void) {
788 struct CitContext *ptr, *rem;
789 struct worker_node **node, *tmp;
792 if ( (time(NULL) - last_purge) < 5 ) return; /* Too soon, go away */
797 begin_critical_section(S_SESSION_TABLE);
798 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
799 if ( (ptr->state == CON_IDLE) && (ptr->kill_me) ) {
803 end_critical_section(S_SESSION_TABLE);
805 /* RemoveContext() enters its own S_SESSION_TABLE critical
806 * section, so we have to do it like this.
809 lprintf(9, "Purging session %d\n", rem->cs_pid);
813 } while (rem != NULL);
816 /* Raise or lower the size of the worker thread pool if such
817 * an action is appropriate.
820 self = pthread_self();
822 if ( (num_sessions > num_threads)
823 && (num_threads < config.c_max_workers) ) {
824 begin_critical_section(S_WORKER_LIST);
826 end_critical_section(S_WORKER_LIST);
829 /* don't let the initial thread die since it's responsible for
830 waiting for all the other threads to terminate. */
831 else if ( (num_sessions < num_threads)
832 && (num_threads > config.c_min_workers)
833 && (self != initial_thread) ) {
835 begin_critical_section(S_WORKER_LIST);
838 /* we're exiting before server shutdown... unlink ourself from
839 the worker list and detach our thread to avoid memory leaks
842 for (node = &worker_list; *node != NULL; node = &(*node)->next)
843 if ((*node)->tid == self) {
845 *node = (*node)->next;
850 pthread_detach(self);
851 end_critical_section(S_WORKER_LIST);
862 * Redirect a session's output to a file or socket.
863 * This function may be called with a file handle *or* a socket (but not
864 * both). Call with neither to return output to its normal client socket.
866 void CtdlRedirectOutput(FILE *fp, int sock) {
868 if (fp != NULL) CC->redirect_fp = fp;
869 else CC->redirect_fp = NULL;
871 if (sock > 0) CC->redirect_sock = sock;
872 else CC->redirect_sock = (-1);
878 * masterCC is the context we use when not attached to a session. This
879 * function initializes it.
881 void InitializeMasterCC(void) {
882 memset(&masterCC, 0, sizeof(struct CitContext));
883 masterCC.internal_pgm = 1;
890 * Set up a fd_set containing all the master sockets to which we
891 * always listen. It's computationally less expensive to just copy
892 * this to a local fd_set when starting a new select() and then add
893 * the client sockets than it is to initialize a new one and then
894 * figure out what to put there.
896 void init_master_fdset(void) {
897 struct ServiceFunctionHook *serviceptr;
900 lprintf(9, "Initializing master fdset\n");
905 lprintf(9, "Will listen on rescan pipe %d\n", rescan[0]);
906 FD_SET(rescan[0], &masterfds);
907 if (rescan[0] > masterhighest) masterhighest = rescan[0];
909 for (serviceptr = ServiceHookTable; serviceptr != NULL;
910 serviceptr = serviceptr->next ) {
911 m = serviceptr->msock;
912 lprintf(9, "Will listen on master socket %d\n", m);
913 FD_SET(m, &masterfds);
914 if (m > masterhighest) {
918 lprintf(9, "masterhighest = %d\n", masterhighest);
924 * Here's where it all begins.
926 int main(int argc, char **argv)
928 char tracefile[128]; /* Name of file to log traces to */
929 int a, i; /* General-purpose variables */
931 int drop_root_perms = 1;
933 struct worker_node *wnp;
935 /* specify default port name and trace file */
936 strcpy(tracefile, "");
938 /* initialize the master context */
939 InitializeMasterCC();
941 /* parse command-line arguments */
942 for (a=1; a<argc; ++a) {
944 /* -t specifies where to log trace messages to */
945 if (!strncmp(argv[a], "-t", 2)) {
946 strcpy(tracefile, argv[a]);
947 strcpy(tracefile, &tracefile[2]);
948 freopen(tracefile, "r", stdin);
949 freopen(tracefile, "w", stdout);
950 freopen(tracefile, "w", stderr);
953 /* run in the background if -d was specified */
954 else if (!strcmp(argv[a], "-d")) {
955 start_daemon( (strlen(tracefile) > 0) ? 0 : 1 ) ;
958 /* -x specifies the desired logging level */
959 else if (!strncmp(argv[a], "-x", 2)) {
960 verbosity = atoi(&argv[a][2]);
963 else if (!strncmp(argv[a], "-h", 2)) {
964 safestrncpy(bbs_home_directory, &argv[a][2],
965 sizeof bbs_home_directory);
969 else if (!strncmp(argv[a], "-f", 2)) {
973 /* -r tells the server not to drop root permissions. don't use
974 * this unless you know what you're doing. this should be
975 * removed in the next release if it proves unnecessary. */
976 else if (!strcmp(argv[a], "-r"))
979 /* any other parameter makes it crash and burn */
981 lprintf(1, "citserver: usage: "
982 "citserver [-tTraceFile] [-d] [-f]"
983 " [-xLogLevel] [-hHomeDir]\n");
989 /* Tell 'em who's in da house */
991 "\nMultithreaded message server for Citadel/UX\n"
992 "Copyright (C) 1987-2001 by the Citadel/UX development team.\n"
993 "Citadel/UX is free software, covered by the GNU General Public License, and\n"
994 "you are welcome to change it and/or distribute copies of it under certain\n"
995 "conditions. There is absolutely no warranty for this software. Please\n"
996 "read the 'COPYING.txt' file for details.\n\n");
1000 openlog("citserver", LOG_PID, LOG_USER);
1002 /* Load site-specific parameters */
1003 lprintf(7, "Loading citadel.config\n");
1008 * Do non system dependent startup functions.
1013 * Bind the server to a Unix-domain socket.
1015 CtdlRegisterServiceHook(0,
1017 citproto_begin_session,
1021 * Bind the server to our favorite TCP port (usually 504).
1023 CtdlRegisterServiceHook(config.c_port_number,
1025 citproto_begin_session,
1029 * Load any server-side modules (plugins) available here.
1031 lprintf(7, "Initializing loadable modules\n");
1032 if ((moddir = malloc(strlen(bbs_home_directory) + 9)) != NULL) {
1033 sprintf(moddir, "%s/modules", bbs_home_directory);
1034 DLoader_Init(moddir);
1039 * The rescan pipe exists so that worker threads can be woken up and
1040 * told to re-scan the context list for fd's to listen on. This is
1041 * necessary, for example, when a context is about to go idle and needs
1042 * to get back on that list.
1045 lprintf(1, "Can't create rescan pipe!\n");
1049 init_master_fdset();
1052 * Now that we've bound the sockets, change to the BBS user id and its
1053 * corresponding group ids
1055 if (drop_root_perms) {
1056 if ((pw = getpwuid(BBSUID)) == NULL)
1057 lprintf(1, "WARNING: getpwuid(%d): %s\n"
1058 "Group IDs will be incorrect.\n", BBSUID,
1061 initgroups(pw->pw_name, pw->pw_gid);
1062 if (setgid(pw->pw_gid))
1063 lprintf(3, "setgid(%d): %s\n", pw->pw_gid,
1066 lprintf(7, "Changing uid to %d\n", BBSUID);
1067 if (setuid(BBSUID) != 0) {
1068 lprintf(3, "setuid() failed: %s\n", strerror(errno));
1072 /* We want to check for idle sessions once per minute */
1073 CtdlRegisterSessionHook(terminate_idle_sessions, EVT_TIMER);
1076 * Now create a bunch of worker threads.
1078 lprintf(9, "Starting %d worker threads\n", config.c_min_workers-1);
1079 begin_critical_section(S_WORKER_LIST);
1080 for (i=0; i<(config.c_min_workers-1); ++i) {
1083 end_critical_section(S_WORKER_LIST);
1085 /* Now this thread can become a worker as well. */
1086 initial_thread = pthread_self();
1087 worker_thread(NULL);
1089 /* Server is exiting. Wait for workers to shutdown. */
1090 lprintf(7, "Waiting for worker threads to shut down\n");
1092 begin_critical_section(S_WORKER_LIST);
1093 while (worker_list != NULL) {
1095 worker_list = wnp->next;
1097 /* avoid deadlock with an exiting thread */
1098 end_critical_section(S_WORKER_LIST);
1099 if ((i = pthread_join(wnp->tid, NULL)))
1100 lprintf(1, "pthread_join: %s\n", strerror(i));
1102 begin_critical_section(S_WORKER_LIST);
1104 end_critical_section(S_WORKER_LIST);
1113 * Bind a thread to a context. (It's inline merely to speed things up.)
1115 inline void become_session(struct CitContext *which_con) {
1116 pthread_setspecific(MyConKey, (void *)which_con );
1122 * This loop just keeps going and going and going...
1124 void *worker_thread(void *arg) {
1128 struct CitContext *ptr;
1129 struct CitContext *bind_me = NULL;
1132 struct CitContext *con= NULL; /* Temporary context pointer */
1133 struct ServiceFunctionHook *serviceptr;
1134 struct sockaddr_in fsin; /* Data for master socket */
1135 int alen; /* Data for master socket */
1136 int ssock; /* Descriptor for client socket */
1143 while (!time_to_die) {
1146 * A naive implementation would have all idle threads
1147 * calling select() and then they'd all wake up at once. We
1148 * solve this problem by putting the select() in a critical
1149 * section, so only one thread has the opportunity to wake
1150 * up. If we wake up on a master socket, create a new
1151 * session context; otherwise, just bind the thread to the
1152 * context we want and go on our merry way.
1155 /* make doubly sure we're not holding any stale db handles
1156 * which might cause a deadlock.
1158 cdb_check_handles();
1160 begin_critical_section(S_I_WANNA_SELECT);
1161 SETUP_FD: memcpy(&readfds, &masterfds, sizeof masterfds);
1162 highest = masterhighest;
1163 begin_critical_section(S_SESSION_TABLE);
1164 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
1165 if (ptr->state == CON_IDLE) {
1166 FD_SET(ptr->client_socket, &readfds);
1167 if (ptr->client_socket > highest)
1168 highest = ptr->client_socket;
1171 end_critical_section(S_SESSION_TABLE);
1173 tv.tv_sec = 1; /* wake up every second if no input */
1178 retval = select(highest + 1, &readfds, NULL, NULL, &tv);
1180 end_critical_section(S_I_WANNA_SELECT);
1184 /* Now figure out who made this select() unblock.
1185 * First, check for an error or exit condition.
1188 if (errno != EINTR) {
1189 lprintf(9, "Exiting (%s)\n", strerror(errno));
1191 } else if (!time_to_die)
1195 /* Next, check to see if it's a new client connecting
1196 * on a master socket.
1198 else for (serviceptr = ServiceHookTable; serviceptr != NULL;
1199 serviceptr = serviceptr->next ) {
1201 if (FD_ISSET(serviceptr->msock, &readfds)) {
1203 ssock = accept(serviceptr->msock,
1204 (struct sockaddr *)&fsin, &alen);
1206 lprintf(2, "citserver: accept(): %s\n",
1210 lprintf(7, "citserver: "
1211 "New client socket %d\n",
1214 /* New context will be created already
1215 * set up in the CON_EXECUTING state.
1217 con = CreateNewContext();
1219 /* Assign new socket number to it. */
1220 con->client_socket = ssock;
1221 con->h_command_function =
1222 serviceptr->h_command_function;
1224 /* Determine whether local socket */
1225 if (serviceptr->sockpath != NULL)
1226 con->is_local_socket = 1;
1228 /* Set the SO_REUSEADDR socket option */
1230 setsockopt(ssock, SOL_SOCKET,
1234 become_session(con);
1236 serviceptr->h_greeting_function();
1237 become_session(NULL);
1238 con->state = CON_IDLE;
1244 /* If the rescan pipe went active, someone is telling this
1245 * thread that the &readfds needs to be refreshed with more
1249 end_critical_section(S_I_WANNA_SELECT);
1253 if (FD_ISSET(rescan[0], &readfds)) {
1254 read(rescan[0], &junk, 1);
1258 /* It must be a client socket. Find a context that has data
1259 * waiting on its socket *and* is in the CON_IDLE state.
1263 begin_critical_section(S_SESSION_TABLE);
1264 for (ptr = ContextList;
1265 ( (ptr != NULL) && (bind_me == NULL) );
1267 if ( (FD_ISSET(ptr->client_socket, &readfds))
1268 && (ptr->state == CON_IDLE) ) {
1272 if (bind_me != NULL) {
1273 /* Found one. Stake a claim to it before
1274 * letting anyone else touch the context list.
1276 bind_me->state = CON_EXECUTING;
1279 end_critical_section(S_SESSION_TABLE);
1280 end_critical_section(S_I_WANNA_SELECT);
1282 /* We're bound to a session, now do *one* command */
1283 if (bind_me != NULL) {
1284 become_session(bind_me);
1285 CC->h_command_function();
1286 become_session(NULL);
1287 bind_me->state = CON_IDLE;
1288 if (bind_me->kill_me == 1) {
1289 RemoveContext(bind_me);
1291 write(rescan[1], &junk, 1);
1295 dead_session_purge();
1297 check_sched_shutdown();
1300 /* If control reaches this point, the server is shutting down */