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"
47 #ifdef HAVE_SYS_SELECT_H
48 #include <sys/select.h>
55 pthread_mutex_t Critters[MAX_SEMAPHORES]; /* Things needing locking */
56 pthread_key_t MyConKey; /* TSD key for MyContext() */
58 int msock; /* master listening socket */
59 int verbosity = 3; /* Logging level */
61 struct CitContext masterCC;
65 * lprintf() ... Write logging information
67 void lprintf(int loglevel, const char *format, ...) {
70 if (loglevel <= verbosity) {
71 va_start(arg_ptr, format);
72 vfprintf(stderr, format, arg_ptr);
81 * Some initialization stuff...
83 void init_sysdep(void) {
86 /* Set up a bunch of semaphores to be used for critical sections */
87 for (a=0; a<MAX_SEMAPHORES; ++a) {
88 pthread_mutex_init(&Critters[a], NULL);
92 * Set up a place to put thread-specific data.
93 * We only need a single pointer per thread - it points to the
94 * thread's CitContext structure in the ContextList linked list.
96 if (pthread_key_create(&MyConKey, NULL) != 0) {
97 lprintf(1, "Can't create TSD key!! %s\n", strerror(errno));
101 * The action for unexpected signals and exceptions should be to
102 * call master_cleanup() to gracefully shut down the server.
104 signal(SIGINT, (void(*)(int))master_cleanup);
105 signal(SIGQUIT, (void(*)(int))master_cleanup);
106 signal(SIGHUP, (void(*)(int))master_cleanup);
107 signal(SIGTERM, (void(*)(int))master_cleanup);
112 * Obtain a semaphore lock to begin a critical section.
114 void begin_critical_section(int which_one)
118 /* lprintf(8, "begin_critical_section(%d)\n", which_one); */
120 /* Don't get interrupted during the critical section */
121 pthread_setcanceltype(PTHREAD_CANCEL_DEFERRED, &oldval);
123 /* Obtain a semaphore */
124 pthread_mutex_lock(&Critters[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); */
137 /* Let go of the semaphore */
138 pthread_mutex_unlock(&Critters[which_one]);
140 /* If a cancel was sent during the critical section, do it now.
141 * Then re-enable thread cancellation.
143 pthread_testcancel();
144 pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, &oldval);
145 pthread_testcancel();
152 * This is a generic function to set up a master socket for listening on
153 * a TCP port. The server shuts down if the bind fails.
155 int ig_tcp_server(int port_number, int queue_len)
157 struct sockaddr_in sin;
160 memset(&sin, 0, sizeof(sin));
161 sin.sin_family = AF_INET;
162 sin.sin_addr.s_addr = INADDR_ANY;
164 if (port_number == 0) {
166 "citserver: No port number specified. Run setup.\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 struct CitContext *retCC;
223 retCC = (struct CitContext *) pthread_getspecific(MyConKey);
224 if (retCC == NULL) retCC = &masterCC;
230 * Wedge our way into the context list.
232 struct CitContext *CreateNewContext(void) {
233 struct CitContext *me;
235 lprintf(9, "CreateNewContext: calling malloc()\n");
236 me = (struct CitContext *) malloc(sizeof(struct CitContext));
238 lprintf(1, "citserver: can't allocate memory!!\n");
241 memset(me, 0, sizeof(struct CitContext));
243 begin_critical_section(S_SESSION_TABLE);
244 me->next = ContextList;
246 end_critical_section(S_SESSION_TABLE);
251 * Add a thread's thread ID to the context
253 void InitMyContext(struct CitContext *con)
257 con->mythread = pthread_self();
258 pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, &oldval);
259 pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, &oldval);
260 if (pthread_setspecific(MyConKey, (void *)con) != 0) {
261 lprintf(1, "ERROR! pthread_setspecific() failed: %s\n",
267 * Remove a context from the context list.
269 void RemoveContext(struct CitContext *con)
271 struct CitContext *ptr;
273 lprintf(7, "Starting RemoveContext()\n");
274 lprintf(9, "Session count before RemoveContext is %d\n",
277 lprintf(7, "WARNING: RemoveContext() called with null!\n");
281 begin_critical_section(S_SESSION_TABLE);
282 lprintf(7, "Closing socket %d\n", con->client_socket);
283 close(con->client_socket);
285 lprintf(9, "Dereferencing session context\n");
286 if (ContextList==con) {
287 ContextList = ContextList->next;
290 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
291 if (ptr->next == con) {
292 ptr->next = con->next;
297 lprintf(9, "Freeing session context...\n");
299 lprintf(9, "...done.\n");
301 lprintf(9, "Session count after RemoveContext is %d\n",
304 lprintf(7, "Done with RemoveContext\n");
305 end_critical_section(S_SESSION_TABLE);
310 * Return the number of sessions currently running.
311 * (This should probably be moved out of sysdep.c)
313 int session_count(void) {
314 struct CitContext *ptr;
317 lprintf(9, "session_count() starting\n");
318 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
320 lprintf(9, "Counted session %3d (%d)\n", ptr->cs_pid, TheCount);
323 lprintf(9, "session_count() finishing\n");
329 * client_write() ... Send binary data to the client.
331 void client_write(char *buf, int nbytes)
333 int bytes_written = 0;
335 while (bytes_written < nbytes) {
336 retval = write(CC->client_socket, &buf[bytes_written],
337 nbytes - bytes_written);
339 lprintf(2, "client_write() failed: %s\n",
343 bytes_written = bytes_written + retval;
349 * cprintf() ... Send formatted printable data to the client. It is
350 * implemented in terms of client_write() but remains in
351 * sysdep.c in case we port to somewhere without va_args...
353 void cprintf(const char *format, ...) {
357 va_start(arg_ptr, format);
358 if (vsnprintf(buf, sizeof buf, format, arg_ptr) == -1)
359 buf[sizeof buf - 2] = '\n';
360 client_write(buf, strlen(buf));
366 * Read data from the client socket.
368 * 1 Requested number of bytes has been read.
369 * 0 Request timed out.
370 * If the socket breaks, the session is immediately terminated.
372 int client_read_to(char *buf, int bytes, int timeout)
382 FD_SET(CC->client_socket, &rfds);
386 retval = select( (CC->client_socket)+1,
387 &rfds, NULL, NULL, &tv);
388 if (FD_ISSET(CC->client_socket, &rfds) == 0) {
392 rlen = read(CC->client_socket, &buf[len], bytes-len);
394 lprintf(2, "client_read() failed: %s\n",
404 * Read data from the client socket with default timeout.
405 * (This is implemented in terms of client_read_to() and could be
406 * justifiably moved out of sysdep.c)
408 int client_read(char *buf, int bytes)
410 return(client_read_to(buf, bytes, config.c_sleeping));
415 * client_gets() ... Get a LF-terminated line of text from the client.
416 * (This is implemented in terms of client_read() and could be
417 * justifiably moved out of sysdep.c)
419 int client_gets(char *buf)
423 /* Read one character at a time.
426 retval = client_read(&buf[i], 1);
427 if (retval != 1 || buf[i] == '\n' || i == 255)
431 /* If we got a long line, discard characters until the newline.
434 while (buf[i] != '\n' && retval == 1)
435 retval = client_read(&buf[i], 1);
437 /* Strip the trailing newline and any trailing nonprintables (cr's)
440 while ((strlen(buf)>0)&&(!isprint(buf[strlen(buf)-1])))
441 buf[strlen(buf)-1] = 0;
448 * The system-dependent part of master_cleanup() - close the master socket.
450 void sysdep_master_cleanup(void) {
451 lprintf(7, "Closing master socket %d\n", msock);
456 * Cleanup routine to be called when one thread is shutting down.
458 void cleanup(int exit_code)
460 /* Terminate the thread.
461 * Its cleanup handler will call cleanup_stuff()
463 lprintf(7, "Calling pthread_exit()\n");
468 * Terminate another session.
470 void kill_session(int session_to_kill) {
471 struct CitContext *ptr;
473 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
474 if (ptr->cs_pid == session_to_kill) {
475 pthread_cancel(ptr->mythread);
482 * The system-dependent wrapper around the main context loop.
484 void *sd_context_loop(struct CitContext *con) {
485 pthread_cleanup_push(*cleanup_stuff, NULL);
487 pthread_cleanup_pop(0);
493 * Start running as a daemon. Only close stdio if do_close_stdio is set.
495 void start_daemon(int do_close_stdio) {
496 if (do_close_stdio) {
501 signal(SIGHUP,SIG_IGN);
502 signal(SIGINT,SIG_IGN);
503 signal(SIGQUIT,SIG_IGN);
504 if (fork()!=0) exit(0);
510 * Tie in to the 'netsetup' program.
512 * (We're going to hope that netsetup never feeds more than 4096 bytes back.)
514 void cmd_nset(char *cmdbuf)
521 char netsetup_args[3][256];
523 if (CC->usersupp.axlevel < 6) {
524 cprintf("%d Higher access required.\n",
525 ERROR + HIGHER_ACCESS_REQUIRED);
529 for (a=1; a<=3; ++a) {
530 if (num_parms(cmdbuf) >= a) {
531 extract(netsetup_args[a-1], cmdbuf, a-1);
532 for (b=0; b<strlen(netsetup_args[a-1]); ++b) {
533 if (netsetup_args[a-1][b] == 34) {
534 netsetup_args[a-1][b] = '_';
539 netsetup_args[a-1][0] = 0;
543 sprintf(fbuf, "./netsetup \"%s\" \"%s\" \"%s\" </dev/null 2>&1",
544 netsetup_args[0], netsetup_args[1], netsetup_args[2]);
545 netsetup = popen(fbuf, "r");
546 if (netsetup == NULL) {
547 cprintf("%d %s\n", ERROR, strerror(errno));
552 while (ch = getc(netsetup), (ch > 0)) {
553 fbuf[strlen(fbuf)+1] = 0;
554 fbuf[strlen(fbuf)] = ch;
557 retcode = pclose(netsetup);
560 for (a=0; a<strlen(fbuf); ++a) {
561 if (fbuf[a] < 32) fbuf[a] = 32;
564 cprintf("%d %s\n", ERROR, fbuf);
568 cprintf("%d Command succeeded. Output follows:\n", LISTING_FOLLOWS);
570 if (fbuf[strlen(fbuf)-1] != 10) cprintf("\n");
577 * Generic routine to convert a login name to a full name (gecos)
578 * Returns nonzero if a conversion took place
580 int convert_login(char NameToConvert[]) {
584 pw = getpwnam(NameToConvert);
589 strcpy(NameToConvert, pw->pw_gecos);
590 for (a=0; a<strlen(NameToConvert); ++a) {
591 if (NameToConvert[a] == ',') NameToConvert[a] = 0;
603 * Here's where it all begins.
605 int main(int argc, char **argv)
607 struct sockaddr_in fsin; /* Data for master socket */
608 int alen; /* Data for master socket */
609 int ssock; /* Descriptor for master socket */
610 THREAD SessThread; /* Thread descriptor */
611 pthread_attr_t attr; /* Thread attributes */
612 struct CitContext *con; /* Temporary context pointer */
613 char tracefile[128]; /* Name of file to log traces to */
614 int a, i; /* General-purpose variables */
618 /* specify default port name and trace file */
619 strcpy(tracefile, "");
621 /* parse command-line arguments */
622 for (a=1; a<argc; ++a) {
624 /* -t specifies where to log trace messages to */
625 if (!strncmp(argv[a], "-t", 2)) {
626 strcpy(tracefile, argv[a]);
627 strcpy(tracefile, &tracefile[2]);
628 freopen(tracefile, "r", stdin);
629 freopen(tracefile, "w", stdout);
630 freopen(tracefile, "w", stderr);
633 /* run in the background if -d was specified */
634 else if (!strcmp(argv[a], "-d")) {
635 start_daemon( (strlen(tracefile) > 0) ? 0 : 1 ) ;
638 /* -x specifies the desired logging level */
639 else if (!strncmp(argv[a], "-x", 2)) {
640 strcpy(convbuf, argv[a]);
641 verbosity = atoi(&convbuf[2]);
644 else if (!strncmp(argv[a], "-h", 2)) {
645 strcpy(convbuf, argv[a]);
646 strcpy(bbs_home_directory, &convbuf[2]);
650 /* any other parameter makes it crash and burn */
652 lprintf(1, "citserver: usage: ");
653 lprintf(1, "citserver [-tTraceFile]");
654 lprintf(1, " [-d] [-xLogLevel] [-hHomeDir]\n");
660 /* Tell 'em who's in da house */
661 lprintf(1, "Multithreaded message server for %s\n", CITADEL);
662 lprintf(1, "Copyright (C) 1987-1998 by Art Cancro. ");
663 lprintf(1, "All rights reserved.\n\n");
667 openlog("citserver",LOG_PID,LOG_USER);
668 lprintf(1, "Initting modules...\n");
669 snprintf(modpath, 128, "%s/modules", BBSDIR);
670 DLoader_Init(modpath);
671 lprintf(1, "Modules done initializing...\n");
673 lprintf(1, "First symtab item:");
674 lprintf(1, my_symtab->fcn_name);
677 /* Load site-specific parameters */
678 lprintf(7, "Loading citadel.config\n");
681 /* Do non system dependent startup functions */
685 * Bind the server to our favourite port.
686 * There is no need to check for errors, because ig_tcp_server()
687 * exits if it doesn't succeed.
689 lprintf(7, "Attempting to bind to port %d...\n", config.c_port_number);
690 msock = ig_tcp_server(config.c_port_number, 5);
691 lprintf(7, "Listening on socket %d\n", msock);
694 * Now that we've bound the socket, change to the BBS user id
695 lprintf(7, "Changing uid to %d\n", BBSUID);
696 if (setuid(BBSUID) != 0) {
697 lprintf(3, "setuid() failed: %s", strerror(errno));
702 * Endless loop. Listen on the master socket. When a connection
703 * comes in, create a socket, a context, and a thread.
706 ssock = accept(msock, (struct sockaddr *)&fsin, &alen);
708 lprintf(2, "citserver: accept() failed: %s\n",
712 lprintf(7, "citserver: Client socket %d\n", ssock);
713 lprintf(9, "creating context\n");
714 con = CreateNewContext();
715 con->client_socket = ssock;
717 /* Set the SO_REUSEADDR socket option */
718 lprintf(9, "setting socket options\n");
720 setsockopt(ssock, SOL_SOCKET, SO_REUSEADDR,
723 /* set attributes for the new thread */
724 lprintf(9, "setting thread attributes\n");
725 pthread_attr_init(&attr);
726 pthread_attr_setdetachstate(&attr,
727 PTHREAD_CREATE_DETACHED);
729 /* now create the thread */
730 lprintf(9, "creating thread\n");
731 if (pthread_create(&SessThread, &attr,
732 (void* (*)(void*)) sd_context_loop,
736 "citserver: can't create thread: %s\n",
741 * (defunct -- now done at thread creation time)
742 * if (pthread_detach(&SessThread) != 0) {
744 * "citserver: can't detach thread: %s\n",
748 lprintf(9, "done!\n");