2 * Citadel/UX "system dependent" stuff.
3 * See copyright.txt for copyright information.
5 * Here's where we (hopefully) have all the parts of the Citadel server that
6 * would need to be altered to run the server in a non-POSIX environment.
7 * Wherever possible, we use function wrappers and type definitions to create
8 * abstractions that are platform-independent from the calling side.
10 * Eventually we'll try porting to a different platform and either have
11 * multiple variants of this file or simply load it up with #ifdefs.
20 #include <sys/types.h>
22 #include <sys/socket.h>
24 #include <netinet/in.h>
34 #include "sysdep_decls.h"
35 #include "citserver.h"
40 #include "housekeeping.h"
43 #include <sys/select.h>
46 extern struct CitContext *ContextList;
47 extern struct config config;
48 extern char bbs_home_directory[];
49 extern int home_specified;
51 pthread_mutex_t Critters[MAX_SEMAPHORES]; /* Things needing locking */
52 pthread_key_t MyConKey; /* TSD key for MyContext() */
54 int msock; /* master listening socket */
55 int verbosity = 3; /* Logging level */
59 * lprintf() ... Write logging information
61 void lprintf(int loglevel, const char *format, ...) {
66 if (loglevel <= verbosity) {
67 va_start(arg_ptr, format);
68 rc = vsprintf(buf, format, arg_ptr);
71 fprintf(stderr, "%s", buf);
79 * Some initialization stuff...
81 void init_sysdep(void) {
84 /* Set up a bunch of semaphores to be used for critical sections */
85 for (a=0; a<MAX_SEMAPHORES; ++a) {
86 pthread_mutex_init(&Critters[a], NULL);
90 * Set up a place to put thread-specific data.
91 * We only need a single pointer per thread - it points to the
92 * thread's CitContext structure in the ContextList linked list.
94 if (pthread_key_create(&MyConKey, NULL) != 0) {
95 lprintf(1, "Can't create TSD key!! %s\n", strerror(errno));
99 * The action for unexpected signals and exceptions should be to
100 * call master_cleanup() to gracefully shut down the server.
102 signal(SIGINT, (void(*)(int))master_cleanup);
103 signal(SIGQUIT, (void(*)(int))master_cleanup);
104 signal(SIGHUP, (void(*)(int))master_cleanup);
105 signal(SIGTERM, (void(*)(int))master_cleanup);
110 * Obtain a semaphore lock to begin a critical section.
112 void begin_critical_section(int which_one)
116 lprintf(8, "begin_critical_section(%d)\n", which_one);
117 if (CC != NULL) hook_crit_get(CC->cs_pid, which_one);
119 /* Don't get interrupted during the critical section */
120 pthread_setcanceltype(PTHREAD_CANCEL_DEFERRED, &oldval);
122 /* Obtain a semaphore */
123 pthread_mutex_lock(&Critters[which_one]);
125 if (CC != NULL) hook_crit_got(CC->cs_pid, which_one);
129 * Release a semaphore lock to end a critical section.
131 void end_critical_section(int which_one)
135 lprintf(8, " end_critical_section(%d)\n", which_one);
136 if (CC != NULL) hook_crit_end(CC->cs_pid, which_one);
138 /* Let go of the semaphore */
139 pthread_mutex_unlock(&Critters[which_one]);
141 /* If a cancel was sent during the critical section, do it now.
142 * Then re-enable thread cancellation.
144 pthread_testcancel();
145 pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, &oldval);
146 pthread_testcancel();
153 * This is a generic function to set up a master socket for listening on
154 * a TCP port. The server shuts down if the bind fails.
156 int ig_tcp_server(int port_number, int queue_len)
158 struct sockaddr_in sin;
161 bzero((char *)&sin, sizeof(sin));
162 sin.sin_family = AF_INET;
163 sin.sin_addr.s_addr = INADDR_ANY;
165 if (port_number == 0) {
166 lprintf(1, "citserver: No port number specified. Run setup again.\n");
170 sin.sin_port = htons((u_short)port_number);
172 s = socket(PF_INET, SOCK_STREAM, (getprotobyname("tcp")->p_proto));
174 lprintf(1, "citserver: Can't create a socket: %s\n",
179 /* Set the SO_REUSEADDR socket option, because it makes sense. */
181 setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &i, sizeof(i));
183 if (bind(s, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
184 lprintf(1, "citserver: Can't bind: %s\n", strerror(errno));
188 if (listen(s, queue_len) < 0) {
189 lprintf(1, "citserver: Can't listen: %s\n", strerror(errno));
198 * Return a pointer to a thread's own CitContext structure (old)
199 * NOTE: this version of MyContext() is commented out because it is no longer
200 * in use. It was written before I discovered TSD keys. This
201 * version pounds through the context list until it finds the one matching
202 * the currently running thread. It remains here, commented out, in case it
203 * is needed for future ports to threading libraries which have the equivalent
204 * of pthread_self() but not pthread_key_create() and its ilk.
206 * struct CitContext *MyContext() {
207 * struct CitContext *ptr;
210 * me = pthread_self();
211 * for (ptr=ContextList; ptr!=NULL; ptr=ptr->next) {
212 * if (ptr->mythread == me) return(ptr);
219 * Return a pointer to a thread's own CitContext structure (new)
221 struct CitContext *MyContext(void) {
222 return (struct CitContext *) pthread_getspecific(MyConKey);
227 * Wedge our way into the context list.
229 struct CitContext *CreateNewContext(void) {
230 struct CitContext *me;
232 lprintf(9, "CreateNewContext: calling malloc()\n");
233 me = (struct CitContext *) malloc(sizeof(struct CitContext));
235 lprintf(1, "citserver: can't allocate memory!!\n");
238 bzero(me, sizeof(struct CitContext));
240 begin_critical_section(S_SESSION_TABLE);
241 me->next = ContextList;
243 end_critical_section(S_SESSION_TABLE);
248 * Add a thread's thread ID to the context
250 void InitMyContext(struct CitContext *con)
254 con->mythread = pthread_self();
255 pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, &oldval);
256 pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, &oldval);
257 if (pthread_setspecific(MyConKey, (void *)con) != 0) {
258 lprintf(1, "ERROR! pthread_setspecific() failed: %s\n",
264 * Remove a context from the context list.
266 void RemoveContext(struct CitContext *con)
268 struct CitContext *ptr;
270 lprintf(7, "Starting RemoveContext()\n");
271 lprintf(9, "session count before RemoveContext is %d\n", session_count());
273 lprintf(7, "WARNING: RemoveContext() called with null!\n");
277 begin_critical_section(S_SESSION_TABLE);
278 lprintf(7, "Closing socket %d\n", con->client_socket);
279 close(con->client_socket);
281 if (ContextList==con) {
282 ContextList = ContextList->next;
285 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
286 if (ptr->next == con) {
287 ptr->next = ptr->next->next;
294 lprintf(9, "session count after RemoveContext is %d\n", session_count());
296 lprintf(7, "Done with RemoveContext\n");
297 end_critical_section(S_SESSION_TABLE);
302 * Return the number of sessions currently running.
303 * (This should probably be moved out of sysdep.c)
305 int session_count(void) {
306 struct CitContext *ptr;
309 lprintf(9, "session_count() starting\n");
310 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
312 lprintf(9, "Counted session %3d (%d)\n", ptr->cs_pid, TheCount);
315 lprintf(9, "session_count() finishing\n");
321 * client_write() ... Send binary data to the client.
323 void client_write(char *buf, int nbytes)
325 int bytes_written = 0;
327 while (bytes_written < nbytes) {
328 retval = write(CC->client_socket, &buf[bytes_written],
329 nbytes - bytes_written);
331 lprintf(2, "client_write() failed: %s\n",
335 bytes_written = bytes_written + retval;
341 * cprintf() ... Send formatted printable data to the client. It is
342 * implemented in terms of client_write() but remains in
343 * sysdep.c in case we port to somewhere without va_args...
345 void cprintf(const char *format, ...) {
350 va_start(arg_ptr, format);
351 rc = vsprintf(buf, format, arg_ptr);
354 client_write(buf, strlen(buf));
359 * Read data from the client socket.
361 * 1 Requested number of bytes has been read.
362 * 0 Request timed out.
363 * If the socket breaks, the session is immediately terminated.
365 int client_read_to(char *buf, int bytes, int timeout)
375 FD_SET(CC->client_socket, &rfds);
379 retval = select( (CC->client_socket)+1,
380 &rfds, NULL, NULL, &tv);
381 if (FD_ISSET(CC->client_socket, &rfds) == 0) {
385 rlen = read(CC->client_socket, &buf[len], bytes-len);
387 lprintf(2, "client_read() failed: %s\n",
397 * Read data from the client socket with default timeout.
398 * (This is implemented in terms of client_read_to() and could be
399 * justifiably moved out of sysdep.c)
401 int client_read(char *buf, int bytes)
403 return(client_read_to(buf, bytes, config.c_sleeping));
408 * client_gets() ... Get a LF-terminated line of text from the client.
409 * (This is implemented in terms of client_read() and could be
410 * justifiably moved out of sysdep.c)
412 int client_gets(char *buf)
416 /* Clear the buffer, and read one character at a time.
420 if (strlen(buf)<255) {
421 buf[strlen(buf) + 1] = 0;
422 retval = client_read(&buf[strlen(buf)], 1);
424 } while ( (buf[strlen(buf)-1] != 10) && (retval==1) );
426 /* Strip the trailing newline.
428 if (strlen(buf) > 0) buf[strlen(buf)-1] = 0;
435 * The system-dependent part of master_cleanup() - close the master socket.
437 void sysdep_master_cleanup(void) {
438 lprintf(7, "Closing master socket %d\n", msock);
443 * Cleanup routine to be called when one thread is shutting down.
445 void cleanup(int exit_code)
447 /* Terminate the thread.
448 * Its cleanup handler will call cleanup_stuff()
450 lprintf(7, "Calling pthread_exit()\n");
455 * Terminate another session.
457 void kill_session(int session_to_kill) {
458 struct CitContext *ptr;
460 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
461 if (ptr->cs_pid == session_to_kill) {
462 pthread_cancel(ptr->mythread);
469 * The system-dependent wrapper around the main context loop.
471 void sd_context_loop(struct CitContext *con) {
472 pthread_cleanup_push(*cleanup_stuff, NULL);
474 pthread_cleanup_pop(0);
479 * Start running as a daemon. Only close stdio if do_close_stdio is set.
481 void start_daemon(int do_close_stdio) {
482 if (do_close_stdio) {
487 signal(SIGHUP,SIG_IGN);
488 signal(SIGINT,SIG_IGN);
489 signal(SIGQUIT,SIG_IGN);
490 if (fork()!=0) exit(0);
496 * Tie in to the 'netsetup' program.
498 * (We're going to hope that netsetup never feeds more than 4096 bytes back.)
500 void cmd_nset(char *cmdbuf)
507 char netsetup_args[3][256];
509 if (CC->usersupp.axlevel < 6) {
510 cprintf("%d Higher access required.\n",
511 ERROR + HIGHER_ACCESS_REQUIRED);
515 for (a=1; a<=3; ++a) {
516 if (num_parms(cmdbuf) >= a) {
517 extract(netsetup_args[a-1], cmdbuf, a-1);
518 for (b=0; b<strlen(netsetup_args[a-1]); ++b) {
519 if (netsetup_args[a-1][b] == 34) {
520 netsetup_args[a-1][b] = '_';
525 netsetup_args[a-1][0] = 0;
529 sprintf(fbuf, "./netsetup \"%s\" \"%s\" \"%s\" </dev/null 2>&1",
530 netsetup_args[0], netsetup_args[1], netsetup_args[2]);
531 netsetup = popen(fbuf, "r");
532 if (netsetup == NULL) {
533 cprintf("%d %s\n", ERROR, strerror(errno));
538 while (ch = getc(netsetup), (ch > 0)) {
539 fbuf[strlen(fbuf)+1] = 0;
540 fbuf[strlen(fbuf)] = ch;
543 retcode = pclose(netsetup);
546 for (a=0; a<strlen(fbuf); ++a) {
547 if (fbuf[a] < 32) fbuf[a] = 32;
550 cprintf("%d %s\n", ERROR, fbuf);
554 cprintf("%d Command succeeded. Output follows:\n", LISTING_FOLLOWS);
556 if (fbuf[strlen(fbuf)-1] != 10) cprintf("\n");
563 * Generic routine to convert a login name to a full name (gecos)
564 * Returns nonzero if a conversion took place
566 int convert_login(char NameToConvert[]) {
570 pw = getpwnam(NameToConvert);
575 strcpy(NameToConvert, pw->pw_gecos);
576 for (a=0; a<strlen(NameToConvert); ++a) {
577 if (NameToConvert[a] == ',') NameToConvert[a] = 0;
589 * Here's where it all begins.
591 int main(int argc, char **argv)
593 struct sockaddr_in fsin; /* Data for master socket */
594 int alen; /* Data for master socket */
595 int ssock; /* Descriptor for master socket */
596 THREAD SessThread; /* Thread descriptor */
597 pthread_attr_t attr; /* Thread attributes */
598 struct CitContext *con; /* Temporary context pointer */
599 char tracefile[128]; /* Name of file to log traces to */
600 int a, i; /* General-purpose variables */
603 /* specify default port name and trace file */
604 strcpy(tracefile, "");
606 /* parse command-line arguments */
607 for (a=1; a<argc; ++a) {
609 /* -t specifies where to log trace messages to */
610 if (!strncmp(argv[a], "-t", 2)) {
611 strcpy(tracefile, argv[a]);
612 strcpy(tracefile, &tracefile[2]);
613 freopen(tracefile, "r", stdin);
614 freopen(tracefile, "w", stdout);
615 freopen(tracefile, "w", stderr);
618 /* run in the background if -d was specified */
619 else if (!strcmp(argv[a], "-d")) {
620 start_daemon( (strlen(tracefile) > 0) ? 0 : 1 ) ;
623 /* -x specifies the desired logging level */
624 else if (!strncmp(argv[a], "-x", 2)) {
625 strcpy(convbuf, argv[a]);
626 verbosity = atoi(&convbuf[2]);
629 else if (!strncmp(argv[a], "-h", 2)) {
630 strcpy(convbuf, argv[a]);
631 strcpy(bbs_home_directory, &convbuf[2]);
635 /* any other parameter makes it crash and burn */
637 lprintf(1, "citserver: usage: ");
638 lprintf(1, "citserver [-tTraceFile]");
639 lprintf(1, " [-d] [-xLogLevel] [-hHomeDir]\n");
645 /* Tell 'em who's in da house */
646 lprintf(1, "Multithreaded message server for %s\n", CITADEL);
647 lprintf(1, "Copyright (C) 1987-1998 by Art Cancro. ");
648 lprintf(1, "All rights reserved.\n\n");
652 openlog("citserver",LOG_PID,LOG_USER);
654 /* Load site-specific parameters */
655 lprintf(7, "Loading citadel.config\n");
659 /* Databases must be opened *after* config is loaded, otherwise we might
660 * end up working in the wrong directory.
662 lprintf(7, "Opening databases\n");
665 lprintf(7, "Checking floor reference counts\n");
669 * Bind the server to our favourite port.
670 * There is no need to check for errors, because ig_tcp_server()
671 * exits if it doesn't succeed.
673 lprintf(7, "Attempting to bind to port %d...\n", config.c_port_number);
674 msock = ig_tcp_server(config.c_port_number, 5);
675 lprintf(7, "Listening on socket %d\n", msock);
678 * Now that we've bound the socket, change to the BBS user id
679 lprintf(7, "Changing uid to %d\n", BBSUID);
680 if (setuid(BBSUID) != 0) {
681 lprintf(3, "setuid() failed: %s", strerror(errno));
686 * Endless loop. Listen on the master socket. When a connection
687 * comes in, create a socket, a context, and a thread.
690 ssock = accept(msock, (struct sockaddr *)&fsin, &alen);
692 lprintf(2, "citserver: accept() failed: %s\n",
696 lprintf(7, "citserver: Client socket %d\n", ssock);
697 lprintf(9, "creating context\n");
698 con = CreateNewContext();
699 con->client_socket = ssock;
701 /* Set the SO_REUSEADDR socket option */
702 lprintf(9, "setting socket options\n");
704 setsockopt(ssock, SOL_SOCKET, SO_REUSEADDR,
707 /* set attributes for the new thread */
708 lprintf(9, "setting thread attributes\n");
709 pthread_attr_init(&attr);
710 pthread_attr_setdetachstate(&attr,
711 PTHREAD_CREATE_DETACHED);
713 /* now create the thread */
714 lprintf(9, "creating thread\n");
715 if (pthread_create(&SessThread, &attr, (void *)sd_context_loop,
718 "citserver: can't create thread: %s\n",
723 * (defunct -- now done at thread creation time)
724 * if (pthread_detach(&SessThread) != 0) {
726 * "citserver: can't detach thread: %s\n",
730 lprintf(9, "done!\n");