/*
 * HybServ TS Services, Copyright (C) 1998-1999 Patrick Alken
 * This program comes with absolutely NO WARRANTY
 *
 * Should you choose to use and/or modify this source code, please
 * do so under the terms of the GNU General Public License under which
 * this program is distributed.
 *
 * $Id: hybserv.c,v 1.3 2001/11/12 09:50:55 asuffield Exp $
 */

#include "defs.h"

#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/resource.h>
#include <unistd.h>
#include <time.h>
#include <errno.h>
#ifdef TIME_WITH_SYS_TIME
#include <sys/time.h>
#endif

#ifndef HAVE_CYGWIN
#include <signal.h>
#else
#include <sys/signal.h>
#endif /* HAVE_CYGWIN */

#include <sys/utsname.h>

#include "alloc.h"
#include "config.h"
#include "data.h"
#include "dcc.h"
#include "hash.h"
#include "hybdefs.h"
#include "init.h"
#include "log.h"
#include "operserv.h"
#include "server.h"
#include "settings.h"
#include "show.h"
#include "sock.h"
#include "timer.h"
#include "timestr.h"
#include "misc.h"

#ifdef HAVE_SOLARIS_THREADS
#include <thread.h>
#include <synch.h>
#else
#ifdef HAVE_PTHREADS
#include <pthread.h>
#endif
#endif

/* unixtime of when services was started */
time_t                       TimeStarted;

/* offset from UTC time */
long                         gmt_offset;

struct NetworkInfo           *Network;

/* structure containing services' info */
struct MyInfo                Me;

/*
 * Set to 1 "ConnectBurst" seconds after a successful
 * hub connection, so we don't send bursts of client/clone
 * connections to +y users etc, during an initial connect.
 */
int                          SafeConnect = 0;

#ifdef HAVE_PTHREADS
/* FD to a named fifo that accepts commands like "DIE" */
int control_pipe;
#endif

int main(int argc, char *argv[])
{
#ifndef DEBUGMODE
  pid_t pid; /* pid of this process */
#endif /* DEBUGMODE */

#ifdef GDB_DEBUG
  int GDBAttached = 0; 
#endif /* GDB_DEBUG */

#if defined GIMMECORE || defined DEBUGMODE
  struct rlimit rlim; /* resource limits -kre */
#endif /* GIMMECORE || DEBUGMODE */

  FILE *pidfile; /* to write our pid */
  uid_t uid, /* real user id */
        euid; /* effective user id */
  struct utsname un;

#ifdef HAVE_SOLARIS_THREADS
  thread_t selectid;
  thread_t timerid;

#else

#ifdef HAVE_PTHREADS
  pthread_attr_t attr;
  pthread_t selectid;
  pthread_t timerid;
#endif /* HAVE_PTHREADS */

#endif /* HAVE_SOLARIS_THREADS */

  /* Initialise current TS for services -kre */
  TimeStarted = current_ts = time(NULL);

  fprintf(stderr,
    "dancer-services version %s by dancer team\n"
#if defined __DATE__ && defined __TIME__
    "Compiled at %s, %s\n",
#endif
    hVersion
#if defined __DATE__ && defined __TIME__
    , __DATE__, __TIME__
#endif
    );

  if (uname(&un) != -1)
  {
    fprintf(stderr, "Running on: %s %s\n", un.sysname,
      un.release);
  }
  else
    /* Blah. It ignored uname(), then pretend to be funny :-) -kre */
    fprintf(stderr, "Running on: computer, probably :-)\n");

#ifdef GDB_DEBUG
  while (!GDBAttached) 
    sleep(1);
#endif /* GDB_DEBUG */  

  /*
   * Load SETPATH (settings.conf) - this must be done
   * before the config file is loaded, and before any
   * putlog() calls are made, since LogFile is specified
   * in settings.conf
   */
  if (LoadSettings(0) == 0)
  {
    fprintf(stderr, "Fatal errors encountered parsing %s, exiting\n"
      "Check logfile %s\n", SETPATH, LogFile ? LogFile : "*unknown*");
    return (0);
  }

  /*
   * If they run ./shownicks or ./showchans rather than ./hybserv
   * display nicknames/channels
   */
  if (strstr(argv[0], "shownicks"))
  {
  #ifdef NICKSERVICES
    ShowNicknames(argc, argv);
  #endif /* NICKSERVICES */
    return (0);
  }
  else if (strstr(argv[0], "showchans"))
  {
  #if defined(NICKSERVICES) && defined(CHANNELSERVICES)
    ShowChannels(argc, argv);
  #endif /* defined(NICKSERVICES) && defined(CHANNELSERVICES) */
    return (0);
  }

  /* Check for running services -kre */
  if ((pidfile = fopen(PidFile, "r")) == NULL)
    putlog(LOG1, "Unable to read %s", PidFile);
  else
  {
    pid_t mypid;
    fscanf(pidfile, "%u", &mypid);
    fclose(pidfile);
    if (!kill(mypid, 0))
    {
      fprintf(stderr, "Services are already running!\n");
      exit(1);
    }
  }

  putlog(LOG1, "dancer-services started");

  /*
   * Get the offset from GMT (London time)
   */
  gmt_offset = GetGMTOffset(TimeStarted);

#if 0
  tm_gmt = gmtime(&TimeStarted);
  gmt_offset = TimeStarted - mktime(tm_gmt);
#endif /* 0 */

  uid = getuid(); /* the user id of the user who ran the process */
  euid = geteuid(); /* the effective id (different if setuid) */

  if (chdir(HPath) != 0)
  {
    fprintf(stderr,
      "HPath is an invalid directory, please check %s\n",
      SETPATH);
    putlog(LOG1, "Invalid HPath (%s), shutting down", HPath);
    exit(0);
  }

  if (!uid || !euid)
  {
    /*
     * It is setuid root or running as root
     * Let us chroot() hybserv then. -kre
     */
    putlog(LOG1, "Detected running with root uid, chrooting");

    if (chroot(HPath))
    {
      fprintf(stderr, "Cannot chroot, exiting.\n");
      putlog(LOG1,"Cannot chroot, shutting down");
      exit(1);
    }
  }

  /* Be sure, be paranoid, be safe. -kre */
  umask(077);

  /*
   * the Network list must be initialized before the config
   * file is loaded
   */
  InitLists();

  /* load server, jupe, gline, user, admin info */
  LoadConfig(ConfigFile);

  /* load nick/chan/memo/stat databases */
  LoadData();

#ifdef GLOBALSERVICES

  if (LogonNews)
  {
    Network->LogonNewsFile.filename = LogonNews;
    ReadMessageFile(&Network->LogonNewsFile);
  }

#endif /* GLOBALSERVICES */

  if (LocalHostName)
    SetupVirtualHost();

#if !defined DEBUGMODE && !defined GDB_DEBUG
  pid = fork();
  if (pid == (-1))
  {
    printf("Unable to fork(), exiting.\n");
    exit(1);
  }
  if (pid != 0)
  {
    printf("Running in background (pid: %d)\n", pid);
    exit(0);
  }

  /* Make current process session leader -kre */
  setsid(); 
#else
  printf("Entering foreground debug mode\n");
#endif /* DEBUGMODE */

#if defined GIMMECORE || defined DEBUGMODE
  printf("Setting corefile limit... ");
  /* Set corefilesize to maximum - therefore we ensure that core will be
   * generated, no matter of shell limits -kre */
  getrlimit(RLIMIT_CORE, &rlim);
  rlim.rlim_cur = rlim.rlim_max;
  setrlimit(RLIMIT_CORE, &rlim);
  printf("done.\n");
#endif /* GIMMECORE || DEBUGMODE */

  /* Signals must be set up after fork(), since the parent exits */
  InitSignals();

  /* Initialise random number generator -kre */
  srandom(current_ts + getpid());

  /* Write our pid to a file */
  if ((pidfile = fopen(PidFile, "w")) == NULL)
    putlog(LOG1, "Unable to open %s", PidFile);
  else
  {
    fprintf(pidfile, "%u\n", getpid());
    fclose(pidfile);
  }

#ifdef HAVE_PTHREADS
  /* Create the control pipe */
  if (unlink(PipeFile) == -1)
    {
      if (errno != ENOENT)
	putlog(LOG1, "Unable to remove old control pipe %s: %s",
	       PipeFile, strerror(errno));
    }
  if (mkfifo(PipeFile, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP) == -1)
    {
      putlog(LOG1, "Unable to create control pipe %s: %s",
	     PipeFile, strerror(errno));
    }
  if ((control_pipe = open(PipeFile, O_RDONLY | O_NONBLOCK)) == -1)
    putlog(LOG1, "Unable to open control pipe %s: %s",
	   PipeFile, strerror(errno));
#endif
  /* initialize tcm/user listening ports */
  InitListenPorts();

  /* initialize hash tables */
  ClearHashes(1);

#ifdef BLOCK_ALLOCATION
  InitHeaps();
#endif

  HubSock = NOSOCKET;
  CycleServers();

#ifdef HAVE_SOLARIS_THREADS

  /* This thread will call DoTimer() every second -kre */
  thr_create(NULL, 0, p_CheckTime, NULL, THR_DETACHED, &timerid);

#else

#ifdef HAVE_PTHREADS

  /* This thread will call DoTimer() every second */
  pthread_attr_init(&attr);
  pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
  pthread_create(&timerid, &attr, p_CheckTime, NULL);

#endif /* HAVE_PTHREADS */

#endif /* HAVE_SOLARIS_THREADS */

  while (1)
  {
    /* enter loop waiting for server info */
#ifdef HAVE_SOLARIS_THREADS

    thr_create(NULL, 0, (void *) &ReadSocketInfo, NULL,
                    THR_BOUND, &selectid);
    thr_join(selectid, NULL, NULL);

#else

#ifdef HAVE_PTHREADS

    read_socket_done = 0;
    pthread_create(&selectid, NULL, (void * (*)(void *))&ReadSocketInfo, NULL);
    /* OK, here is a hacky control pipe implementation */
    while (!read_socket_done)
      {
	fd_set rfds;
	struct timeval tv;

	if (control_pipe != -1)
	  {
	    FD_ZERO(&rfds);
	    FD_SET(control_pipe, &rfds);
	    tv.tv_sec = 1;
	    tv.tv_usec = 0;

	    if (select(control_pipe + 1, &rfds, NULL, NULL, &tv))
	      {
		static char buf[512];
		int len = read(control_pipe, buf, 511);
		char *p = buf, *next;

		if (len == -1)
		  {
		    putlog(LOG1, "Control pipe %s read() failed: %s",
			   PipeFile, strerror(errno));
		    close(control_pipe);
		    control_pipe = -1;
		  }
		else
		  {
		    buf[511] = '\0';
		    buf[len] = '\0';
		    next = strchr(buf, '\n');

		    /* Terminate at the first \n, throw the lot away if we don't get one */
		    while (next)
		      {
			*next = '\0';
			if (strncmp("DIE", p, 4) == 0)
			  {
			    putlog(LOG1, "Received DIE on control pipe");
			    DoShutdown("control_pipe", "Received DIE");
			  }
			p = next + 1; /* At most points to buf[511], since strchr() can never get past that \0 */
			next = strchr(p, '\n');
		      }
		    memmove(buf, p, strlen(p) + 1);
		  }
	      }
	  }
      }
    pthread_join(selectid, NULL);

#else
  
    ReadSocketInfo();

#endif /* HAVE_PTHREADS */

#endif /* HAVE_SOLARIS_THREADS */

    if (Me.hub)
      SendUmode(OPERUMODE_Y, "*** Disconnected from %s", Me.hub->name);
    else
      SendUmode(OPERUMODE_Y, "*** Disconnected from hub server");

    if (currenthub)
      if (currenthub->realname)
      {
        MyFree(currenthub->realname);
        currenthub->realname = NULL;
      }

    close(HubSock); /* There was an error */
    HubSock = NOSOCKET;
    currenthub->connect_ts = 0;

    /* 
     * whenever HybServ connects/reconnects to a server, clear
     * users, servers, and chans
     */
    ClearUsers();
    ClearChans();
    ClearServs();
    /*
     * ClearHashes() must be called AFTER ClearUsers(),
     * or StatServ's unique client counts will be off since
     * cloneTable[] would be NULL while it was trying to find
     * clones
     */
    ClearHashes(0);

    PostCleanup();
  } /* while (1) */

  return (0);
} /* main() */