2 * Citadel/UX "system dependent" stuff.
3 * See copyright.txt for copyright information.
7 * Here's where we (hopefully) have all the parts of the Citadel server that
8 * would need to be altered to run the server in a non-POSIX environment.
9 * Wherever possible, we use function wrappers and type definitions to create
10 * abstractions that are platform-independent from the calling side.
12 * Eventually we'll try porting to a different platform and either have
13 * multiple variants of this file or simply load it up with #ifdefs.
23 #include <sys/types.h>
25 #include <sys/socket.h>
28 #include <netinet/in.h>
38 #include "sysdep_decls.h"
39 #include "citserver.h"
43 #include "housekeeping.h"
44 #include "dynloader.h"
46 #ifdef HAVE_SYS_SELECT_H
47 #include <sys/select.h>
54 pthread_mutex_t Critters[MAX_SEMAPHORES]; /* Things needing locking */
55 pthread_key_t MyConKey; /* TSD key for MyContext() */
57 int msock; /* master listening socket */
58 int verbosity = 3; /* Logging level */
60 struct CitContext masterCC;
64 * lprintf() ... Write logging information
66 void lprintf(int loglevel, const char *format, ...) {
69 if (loglevel <= verbosity) {
70 va_start(arg_ptr, format);
71 vfprintf(stderr, format, arg_ptr);
80 * Some initialization stuff...
82 void init_sysdep(void) {
85 /* Set up a bunch of semaphores to be used for critical sections */
86 for (a=0; a<MAX_SEMAPHORES; ++a) {
87 pthread_mutex_init(&Critters[a], NULL);
91 * Set up a place to put thread-specific data.
92 * We only need a single pointer per thread - it points to the
93 * thread's CitContext structure in the ContextList linked list.
95 if (pthread_key_create(&MyConKey, NULL) != 0) {
96 lprintf(1, "Can't create TSD key!! %s\n", strerror(errno));
100 * The action for unexpected signals and exceptions should be to
101 * call master_cleanup() to gracefully shut down the server.
103 signal(SIGINT, (void(*)(int))master_cleanup);
104 signal(SIGQUIT, (void(*)(int))master_cleanup);
105 signal(SIGHUP, (void(*)(int))master_cleanup);
106 signal(SIGTERM, (void(*)(int))master_cleanup);
111 * Obtain a semaphore lock to begin a critical section.
113 void begin_critical_section(int which_one)
117 /* lprintf(8, "begin_critical_section(%d)\n", 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]);
128 * Release a semaphore lock to end a critical section.
130 void end_critical_section(int which_one)
134 /* lprintf(8, " end_critical_section(%d)\n", which_one); */
136 /* Let go of the semaphore */
137 pthread_mutex_unlock(&Critters[which_one]);
139 /* If a cancel was sent during the critical section, do it now.
140 * Then re-enable thread cancellation.
142 pthread_testcancel();
143 pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, &oldval);
144 pthread_testcancel();
151 * This is a generic function to set up a master socket for listening on
152 * a TCP port. The server shuts down if the bind fails.
154 int ig_tcp_server(int port_number, int queue_len)
156 struct sockaddr_in sin;
159 memset(&sin, 0, sizeof(sin));
160 sin.sin_family = AF_INET;
161 sin.sin_addr.s_addr = INADDR_ANY;
163 if (port_number == 0) {
165 "citserver: No port number specified. Run setup.\n");
169 sin.sin_port = htons((u_short)port_number);
171 s = socket(PF_INET, SOCK_STREAM, (getprotobyname("tcp")->p_proto));
173 lprintf(1, "citserver: Can't create a socket: %s\n",
178 /* Set the SO_REUSEADDR socket option, because it makes sense. */
180 setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &i, sizeof(i));
182 if (bind(s, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
183 lprintf(1, "citserver: Can't bind: %s\n", strerror(errno));
187 if (listen(s, queue_len) < 0) {
188 lprintf(1, "citserver: Can't listen: %s\n", strerror(errno));
197 * Return a pointer to a thread's own CitContext structure (old)
198 * NOTE: this version of MyContext() is commented out because it is no longer
199 * in use. It was written before I discovered TSD keys. This
200 * version pounds through the context list until it finds the one matching
201 * the currently running thread. It remains here, commented out, in case it
202 * is needed for future ports to threading libraries which have the equivalent
203 * of pthread_self() but not pthread_key_create() and its ilk.
205 * struct CitContext *MyContext() {
206 * struct CitContext *ptr;
209 * me = pthread_self();
210 * for (ptr=ContextList; ptr!=NULL; ptr=ptr->next) {
211 * if (ptr->mythread == me) return(ptr);
218 * Return a pointer to a thread's own CitContext structure (new)
220 struct CitContext *MyContext(void) {
221 struct CitContext *retCC;
222 retCC = (struct CitContext *) pthread_getspecific(MyConKey);
223 if (retCC == NULL) retCC = &masterCC;
229 * Wedge our way into the context list.
231 struct CitContext *CreateNewContext(void) {
232 struct CitContext *me;
234 lprintf(9, "CreateNewContext: calling malloc()\n");
235 me = (struct CitContext *) malloc(sizeof(struct CitContext));
237 lprintf(1, "citserver: can't allocate memory!!\n");
240 memset(me, 0, sizeof(struct CitContext));
242 begin_critical_section(S_SESSION_TABLE);
243 me->next = ContextList;
245 end_critical_section(S_SESSION_TABLE);
250 * Add a thread's thread ID to the context
252 void InitMyContext(struct CitContext *con)
256 con->mythread = pthread_self();
257 pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, &oldval);
258 pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, &oldval);
259 if (pthread_setspecific(MyConKey, (void *)con) != 0) {
260 lprintf(1, "ERROR! pthread_setspecific() failed: %s\n",
266 * Remove a context from the context list.
268 void RemoveContext(struct CitContext *con)
270 struct CitContext *ptr;
272 lprintf(7, "Starting RemoveContext()\n");
273 lprintf(9, "Session count before RemoveContext is %d\n",
276 lprintf(7, "WARNING: RemoveContext() called with null!\n");
280 begin_critical_section(S_SESSION_TABLE);
281 lprintf(7, "Closing socket %d\n", con->client_socket);
282 close(con->client_socket);
284 lprintf(9, "Dereferencing session context\n");
285 if (ContextList==con) {
286 ContextList = ContextList->next;
289 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
290 if (ptr->next == con) {
291 ptr->next = con->next;
296 lprintf(9, "Freeing session context...\n");
298 lprintf(9, "...done.\n");
300 lprintf(9, "Session count after RemoveContext is %d\n",
303 lprintf(7, "Done with RemoveContext\n");
304 end_critical_section(S_SESSION_TABLE);
309 * Return the number of sessions currently running.
310 * (This should probably be moved out of sysdep.c)
312 int session_count(void) {
313 struct CitContext *ptr;
316 lprintf(9, "session_count() starting\n");
317 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
319 lprintf(9, "Counted session %3d (%d)\n", ptr->cs_pid, TheCount);
322 lprintf(9, "session_count() finishing\n");
328 * client_write() ... Send binary data to the client.
330 void client_write(char *buf, int nbytes)
332 int bytes_written = 0;
334 while (bytes_written < nbytes) {
335 retval = write(CC->client_socket, &buf[bytes_written],
336 nbytes - bytes_written);
338 lprintf(2, "client_write() failed: %s\n",
342 bytes_written = bytes_written + retval;
348 * cprintf() ... Send formatted printable data to the client. It is
349 * implemented in terms of client_write() but remains in
350 * sysdep.c in case we port to somewhere without va_args...
352 void cprintf(const char *format, ...) {
356 va_start(arg_ptr, format);
357 if (vsnprintf(buf, sizeof buf, format, arg_ptr) == -1)
358 buf[sizeof buf - 2] = '\n';
359 client_write(buf, strlen(buf));
365 * Read data from the client socket.
367 * 1 Requested number of bytes has been read.
368 * 0 Request timed out.
369 * If the socket breaks, the session is immediately terminated.
371 int client_read_to(char *buf, int bytes, int timeout)
381 FD_SET(CC->client_socket, &rfds);
385 retval = select( (CC->client_socket)+1,
386 &rfds, NULL, NULL, &tv);
387 if (FD_ISSET(CC->client_socket, &rfds) == 0) {
391 rlen = read(CC->client_socket, &buf[len], bytes-len);
393 lprintf(2, "client_read() failed: %s\n",
403 * Read data from the client socket with default timeout.
404 * (This is implemented in terms of client_read_to() and could be
405 * justifiably moved out of sysdep.c)
407 int client_read(char *buf, int bytes)
409 return(client_read_to(buf, bytes, config.c_sleeping));
414 * client_gets() ... Get a LF-terminated line of text from the client.
415 * (This is implemented in terms of client_read() and could be
416 * justifiably moved out of sysdep.c)
418 int client_gets(char *buf)
422 /* Read one character at a time.
425 retval = client_read(&buf[i], 1);
426 if (retval != 1 || buf[i] == '\n' || i == 255)
430 /* If we got a long line, discard characters until the newline.
433 while (buf[i] != '\n' && retval == 1)
434 retval = client_read(&buf[i], 1);
436 /* Strip the trailing newline and any trailing nonprintables (cr's)
439 while ((strlen(buf)>0)&&(!isprint(buf[strlen(buf)-1])))
440 buf[strlen(buf)-1] = 0;
447 * The system-dependent part of master_cleanup() - close the master socket.
449 void sysdep_master_cleanup(void) {
450 lprintf(7, "Closing master socket %d\n", msock);
455 * Cleanup routine to be called when one thread is shutting down.
457 void cleanup(int exit_code)
459 /* Terminate the thread.
460 * Its cleanup handler will call cleanup_stuff()
462 lprintf(7, "Calling pthread_exit()\n");
467 * Terminate another session.
469 void kill_session(int session_to_kill) {
470 struct CitContext *ptr;
472 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
473 if (ptr->cs_pid == session_to_kill) {
474 pthread_cancel(ptr->mythread);
481 * The system-dependent wrapper around the main context loop.
483 void *sd_context_loop(struct CitContext *con) {
484 pthread_cleanup_push(*cleanup_stuff, NULL);
486 pthread_cleanup_pop(0);
492 * Start running as a daemon. Only close stdio if do_close_stdio is set.
494 void start_daemon(int do_close_stdio) {
495 if (do_close_stdio) {
500 signal(SIGHUP,SIG_IGN);
501 signal(SIGINT,SIG_IGN);
502 signal(SIGQUIT,SIG_IGN);
503 if (fork()!=0) exit(0);
509 * Tie in to the 'netsetup' program.
511 * (We're going to hope that netsetup never feeds more than 4096 bytes back.)
513 void cmd_nset(char *cmdbuf)
520 char netsetup_args[3][256];
522 if (CC->usersupp.axlevel < 6) {
523 cprintf("%d Higher access required.\n",
524 ERROR + HIGHER_ACCESS_REQUIRED);
528 for (a=1; a<=3; ++a) {
529 if (num_parms(cmdbuf) >= a) {
530 extract(netsetup_args[a-1], cmdbuf, a-1);
531 for (b=0; b<strlen(netsetup_args[a-1]); ++b) {
532 if (netsetup_args[a-1][b] == 34) {
533 netsetup_args[a-1][b] = '_';
538 netsetup_args[a-1][0] = 0;
542 sprintf(fbuf, "./netsetup \"%s\" \"%s\" \"%s\" </dev/null 2>&1",
543 netsetup_args[0], netsetup_args[1], netsetup_args[2]);
544 netsetup = popen(fbuf, "r");
545 if (netsetup == NULL) {
546 cprintf("%d %s\n", ERROR, strerror(errno));
551 while (ch = getc(netsetup), (ch > 0)) {
552 fbuf[strlen(fbuf)+1] = 0;
553 fbuf[strlen(fbuf)] = ch;
556 retcode = pclose(netsetup);
559 for (a=0; a<strlen(fbuf); ++a) {
560 if (fbuf[a] < 32) fbuf[a] = 32;
563 cprintf("%d %s\n", ERROR, fbuf);
567 cprintf("%d Command succeeded. Output follows:\n", LISTING_FOLLOWS);
569 if (fbuf[strlen(fbuf)-1] != 10) cprintf("\n");
576 * Generic routine to convert a login name to a full name (gecos)
577 * Returns nonzero if a conversion took place
579 int convert_login(char NameToConvert[]) {
583 pw = getpwnam(NameToConvert);
588 strcpy(NameToConvert, pw->pw_gecos);
589 for (a=0; a<strlen(NameToConvert); ++a) {
590 if (NameToConvert[a] == ',') NameToConvert[a] = 0;
602 * Here's where it all begins.
604 int main(int argc, char **argv)
606 struct sockaddr_in fsin; /* Data for master socket */
607 int alen; /* Data for master socket */
608 int ssock; /* Descriptor for master socket */
609 THREAD SessThread; /* Thread descriptor */
610 pthread_attr_t attr; /* Thread attributes */
611 struct CitContext *con; /* Temporary context pointer */
612 char tracefile[128]; /* Name of file to log traces to */
613 int a, i; /* General-purpose variables */
617 /* specify default port name and trace file */
618 strcpy(tracefile, "");
620 /* parse command-line arguments */
621 for (a=1; a<argc; ++a) {
623 /* -t specifies where to log trace messages to */
624 if (!strncmp(argv[a], "-t", 2)) {
625 strcpy(tracefile, argv[a]);
626 strcpy(tracefile, &tracefile[2]);
627 freopen(tracefile, "r", stdin);
628 freopen(tracefile, "w", stdout);
629 freopen(tracefile, "w", stderr);
632 /* run in the background if -d was specified */
633 else if (!strcmp(argv[a], "-d")) {
634 start_daemon( (strlen(tracefile) > 0) ? 0 : 1 ) ;
637 /* -x specifies the desired logging level */
638 else if (!strncmp(argv[a], "-x", 2)) {
639 strcpy(convbuf, argv[a]);
640 verbosity = atoi(&convbuf[2]);
643 else if (!strncmp(argv[a], "-h", 2)) {
644 strcpy(convbuf, argv[a]);
645 strcpy(bbs_home_directory, &convbuf[2]);
649 /* any other parameter makes it crash and burn */
651 lprintf(1, "citserver: usage: ");
652 lprintf(1, "citserver [-tTraceFile]");
653 lprintf(1, " [-d] [-xLogLevel] [-hHomeDir]\n");
659 /* Tell 'em who's in da house */
660 lprintf(1, "Multithreaded message server for %s\n", CITADEL);
661 lprintf(1, "Copyright (C) 1987-1998 by Art Cancro. ");
662 lprintf(1, "All rights reserved.\n\n");
666 openlog("citserver",LOG_PID,LOG_USER);
667 lprintf(1, "Initting modules...\n");
668 snprintf(modpath, 128, "%s/modules", BBSDIR);
669 DLoader_Init(modpath);
670 lprintf(1, "Modules done initializing...\n");
672 lprintf(1, "First symtab item:");
673 lprintf(1, my_symtab->fcn_name);
676 /* Load site-specific parameters */
677 lprintf(7, "Loading citadel.config\n");
680 /* Do non system dependent startup functions */
684 * Bind the server to our favourite port.
685 * There is no need to check for errors, because ig_tcp_server()
686 * exits if it doesn't succeed.
688 lprintf(7, "Attempting to bind to port %d...\n", config.c_port_number);
689 msock = ig_tcp_server(config.c_port_number, 5);
690 lprintf(7, "Listening on socket %d\n", msock);
693 * Now that we've bound the socket, change to the BBS user id
694 lprintf(7, "Changing uid to %d\n", BBSUID);
695 if (setuid(BBSUID) != 0) {
696 lprintf(3, "setuid() failed: %s", strerror(errno));
701 * Endless loop. Listen on the master socket. When a connection
702 * comes in, create a socket, a context, and a thread.
705 ssock = accept(msock, (struct sockaddr *)&fsin, &alen);
707 lprintf(2, "citserver: accept() failed: %s\n",
711 lprintf(7, "citserver: Client socket %d\n", ssock);
712 lprintf(9, "creating context\n");
713 con = CreateNewContext();
714 con->client_socket = ssock;
716 /* Set the SO_REUSEADDR socket option */
717 lprintf(9, "setting socket options\n");
719 setsockopt(ssock, SOL_SOCKET, SO_REUSEADDR,
722 /* set attributes for the new thread */
723 lprintf(9, "setting thread attributes\n");
724 pthread_attr_init(&attr);
725 pthread_attr_setdetachstate(&attr,
726 PTHREAD_CREATE_DETACHED);
728 /* now create the thread */
729 lprintf(9, "creating thread\n");
730 if (pthread_create(&SessThread, &attr,
731 (void* (*)(void*)) sd_context_loop,
735 "citserver: can't create thread: %s\n",
740 * (defunct -- now done at thread creation time)
741 * if (pthread_detach(&SessThread) != 0) {
743 * "citserver: can't detach thread: %s\n",
747 lprintf(9, "done!\n");