/*
 * ----------------------------------------------------------------
 * Night Light IRC Proxy - Connection I/O Functions
 * ----------------------------------------------------------------
 * Copyright (C) 1997-2007 Jonas Kvinge <jonas@night-light.net>
 * All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Last modified by:
 * Jonas Kvinge (24.11.2007)
 *
 */

#define CONN_IO_C

#define NEED_SYS_TYPES_H 1		/* Extra types */
#define NEED_SYS_PARAM_H 1		/* Some systems need this */
#define NEED_LIMITS_H 0			/* Kernel limits */
#define NEED_STDARG_H 1			/* va_list, etc */
#define NEED_ERRNO_H 1			/* errno */
#define NEED_CTYPE_H 1			/* isdigit(), etc */
#define NEED_NETINET_IN_H 1		/* in_addr, sockaddr_in, etc */
#define NEED_ARPA_INET_H 1		/* inet_ntoa(), inet_aton(), etc */
#define NEED_STDIO_H 1			/* Standard C UNIX functions */
#define NEED_STDLIB_H 1			/* malloc(), exit(), atoi(), etc */
#define NEED_TIME_H 1			/* time(), etc */
#define NEED_SYSCTL_H 0			/* sysctl(), etc */
#define NEED_SYS_STAT_H 0		/* chmod(), mkdir(), etc */
#define NEED_SYS_UIO_H 0		/* iovec, etc */
#define NEED_FCNTL_H 1			/* open(), creat(), fcntl(), etc */
#define NEED_SYS_IOCTL_H 1		/* ioctl(), etc */
#define NEED_SYS_FILIO_H 1		/* Solaris need this for ioctl(), etc */
#define NEED_UNISTD_H 1			/* Unix standard functions */
#define NEED_STRING_H 1			/* C string functions */
#define NEED_SIGNAL_H 0			/* Signal functions */
#define NEED_SYS_SOCKET_H 1		/* Socket functions */
#define NEED_NETDB_H 1			/* Network database functions */
#define NEED_ARPA_NAMESER_H 0		/* Nameserver definitions */
#define NEED_GETUSERPW_HEADERS 0 	/* Functions to retrive system passwords */
#define NEED_ARES 0			/* Functions needed for ares */
#define NEED_SSL 1			/* Needed for SSL support */

#include "includes.h"
#include "irc.h"

#include "conf.h"

#include "conn_conf.h"

#include "conn.h"
#include "conn_io.h"

#if SSL_SUPPORT
#include "conn_io_ssl.h"
#endif /* SSL_SUPPORT */

#include "conn_connection.h"
#include "conn_sendq.h"
#include "conn_log.h"
#include "conn_parser.h"
#include "conn_ignore.h"

#include "chan.h"
#include "chan_mode.h"

#include "client_notice.h"

/* VARIABLES - JONAS (31.07.2001) */

extern struct Conf_Struct ConfS;
extern struct Conn_Struct *Conn_Head;

/* CONN_FDS FUNCTION - JONAS (22.07.2001) */

void conn_fds(fd_set *ReadFDS, fd_set *WriteFDS, unsigned long int *FDS) {

  struct Conn_Struct *ConnS = NULL;
  struct Conn_Struct *ConnS_DEL = NULL;
  struct Chan_Struct *ChanS = NULL;
  time_t Duration = 0;

  for (ConnS = Conn_Head ; ConnS != NULL ;) {

    if (NOW > ConnS->IgnoreExpireTime) { conn_ignoreexpire(ConnS); }

    FAKELOOP {

      if (!Conn_IsConnect(ConnS)) { break; }

      if (ConnS->NumSendQs > 0) { conn_flushsendq(ConnS); }

      if (!Conn_IsWelcome(ConnS)) {
        Duration = (NOW - ConnS->ConnectTime);
        if (Duration >= CONN_CONNECTTIMEOUT) { conn_disconnect(ConnS, "Connection %s: Connection attempt to server %s(%s):%ld timed out.", ConnS->Name, ConnS->ServerHostName, ConnS->ServerHostIPS, ConnS->ServerPortH); break; }
        break;
      }

      if (Conn_IsSentQuit(ConnS)) {
        Duration = (NOW - ConnS->SentQuitTime);
        if (Duration >= CONN_QUITTIMEOUT) { conn_disconnect(ConnS, "Connection %s: Timeout while waiting for server %s(%s):%ld to close connection.", ConnS->Name, ConnS->ServerHostName, ConnS->ServerHostIPS, ConnS->ServerPortH); break; }
        break;
      }

      if (!Conn_IsWelcome(ConnS)) { break; } /* Don't PING the connection if we haven't received 001 --Jonas */

      /* LAG CHECK */

      if (Conn_IsSentPing(ConnS)) {
        Duration = (NOW - ConnS->SentPingTime);
        if (Duration >= CONN_PINGTIMEOUT) { conn_quit(ConnS, "No response from server in %s", strduration(Duration)); }
      }
      else {
        Duration = (NOW - ConnS->LastRecvTime);
        if (Duration >= CONN_IDLETIMEBEFOREPING) {
          Conn_SetSentPing(ConnS);
          ConnS->SentPingTime = NOW;
          conn_addsendq(ConnS, "PING :PROXY");
        }
      }

      /* REGAIN NICK */

      if ((ConnConf_IsRegainNick(ConnS)) && (!Conn_IsSentISON(ConnS)) && (!Conn_IsSentNick(ConnS)) && (!Conn_IsSentAwayNick(ConnS)) && (strcasecmp(((Conn_IsAwayNick(ConnS)) ? ConnS->AwayNick : ConnS->Nick), ConnS->IRCNick) != FALSE) && (ConnS->NumClients <= 0)) {
        Duration = (NOW - ConnS->SentISONTime);
        if (Duration >= CONN_ISONTIME) {
          Conn_SetSentISON(ConnS);
          ConnS->SentISONTime = NOW;
          conn_addsendq(ConnS, "ISON :%s", ((Conn_IsAwayNick(ConnS)) ? ConnS->AwayNick : ConnS->Nick));
        }
      }

      for (ChanS = ConnS->Chan_Head ; ChanS != NULL ; ChanS = ChanS->Next) {
        if (ChanS->SentModes > 0) {
          Duration = (NOW - ChanS->CheckSentModesTime);
          if (Duration >= CHANMODEEXPIRESENTMODESTIME) { chan_expiresentmodes(ConnS, ChanS); }
        }
        if (ChanS->Modes > 0) {
          Duration = (NOW - ChanS->FlushModesTime);
          if (Duration >= CHANMODEFLUSHMODESTIME) { chan_flushmodes(ConnS, ChanS); }
        }
      }

    }

    if ((Conn_IsSocket(ConnS)) && (Host_IsResolved(ConnS->ResolveFlags))) {
      FD_SET(ConnS->FD, ReadFDS);
      if (ConnS->SendBuffer != NULL) { FD_SET(ConnS->FD, WriteFDS); }
    }

    if ((Conn_IsRemove(ConnS)) && (!Conn_IsConnectProc(ConnS)) && (!Conn_IsSocket(ConnS)) && (!Host_IsResolving(ConnS->ResolveFlags)) && (!Host_IsResolving(ConnS->ServerResolveFlags))) {
      ConnS_DEL = ConnS;
      ConnS = ConnS->Next;
      conn_rem(ConnS_DEL);
      continue;
    }

    if ((ConnConf_IsAutoConnect(ConnS)) && (!Conn_IsRemove(ConnS)) && (!Conn_IsConnectProc(ConnS)) && (!Conn_IsSocket(ConnS))) {
      Duration = (NOW - ConnS->ConnectProcTime);
      if (Duration >= CONN_INTERVAL) {
#if SSL_SUPPORT
        if (ConfS.SSLSupport == TRUE) { conn_connect(ConnS); }
        else if (!ConnConf_IsSSL(ConnS)) { conn_connect(ConnS); }
#else
        if (!ConnConf_IsSSL(ConnS)) { conn_connect(ConnS); }
#endif
      }
    }

    ConnS = ConnS->Next;
    continue;

  }

}

/* CONN_IO FUNCTION - JONAS (01.07.2000) */

void conn_io(fd_set *ReadFDS, fd_set *WriteFDS, unsigned long int *FDS) {

  struct Conn_Struct *ConnS = NULL;

  assert(ReadFDS != NULL);
  assert(WriteFDS != NULL);

  for (ConnS = Conn_Head ; ConnS != NULL ; ConnS = ConnS->Next) {

    assert(*FDS >= 0);
    if (*FDS <= 0) { return; }

    if (Conn_IsSocket(ConnS)) {
      if (FD_ISSET(ConnS->FD, ReadFDS)) { *FDS = *FDS - 1; }
      if (FD_ISSET(ConnS->FD, WriteFDS)) { *FDS = *FDS - 1; }
    }

    if (Conn_IsSocket(ConnS)) {
      if (FD_ISSET(ConnS->FD, ReadFDS)) {
#if SSL_SUPPORT
        if (ConnConf_IsSSL(ConnS)) { conn_recv_ssl(ConnS); }
        else { 
#endif
          conn_recv(ConnS);
#if SSL_SUPPORT
        }
#endif
      }
    }
    if (Conn_IsSocket(ConnS)) {
      if (FD_ISSET(ConnS->FD, WriteFDS)) {
#if SSL_SUPPORT
        if (ConnConf_IsSSL(ConnS)) { conn_send_ssl(ConnS); }
        else {
#endif
          conn_send(ConnS);
#if SSL_SUPPORT
        }
#endif
      }
    }

  }

}

/* CONN_RECV FUNCTION - JONAS (01.07.2000) */

void conn_recv(struct Conn_Struct *ConnS) {

  signed long int Result = 0;
  unsigned long int OldLen = 0;
  unsigned long int NewLen = 0;
  char RecvBuffer[RECVBUFFERLEN+1] = "";
  char *RecvBufferPT = NULL;

  assert(ConnS != NULL);
  assert(Conn_IsSocket(ConnS));
  assert(ConnS->FD != FD_NONE);

  if ((Conn_IsConnectProc(ConnS)) && (Host_IsResolved(ConnS->ResolveFlags))) {
    conn_connect(ConnS);
    if (!Conn_IsSocket(ConnS)) { return; }
  }

  ConnS->LastRecvTime = NOW;

  do {
    memset(&RecvBuffer, 0, sizeof(RecvBuffer));
    Result = recv(ConnS->FD, RecvBuffer, RECVBUFFERLEN, MSG_NOSIGNAL);
    if (Result <= ERROR) {
      if ((errno == EAGAIN) || (errno == EWOULDBLOCK) || (errno == EINTR)) { break; }
      conn_disconnect(ConnS, "Connection %s: Read error to %s(%s):%ld: [%d] %s", ConnS->Name, ConnS->ServerHostName, ConnS->ServerHostIPS, ConnS->ServerPortH, errno, strerror(errno));
      return;
    }
    if (Result == 0) {
      if (ConnS->RecvBuffer != NULL) { conn_parser(ConnS); }
      conn_disconnect(ConnS, "Connection %s: EOF to %s(%s):%ld.", ConnS->Name, ConnS->ServerHostName, ConnS->ServerHostIPS, ConnS->ServerPortH);
      return;
    }

    if (ConnS->RecvBuffer == NULL) { OldLen = 0; }
    else { OldLen = strlen(ConnS->RecvBuffer); }
    NewLen = OldLen + Result + 1;
    RecvBufferPT = realloc(ConnS->RecvBuffer, NewLen);
    if (RecvBufferPT == NULL) {
      conn_disconnect(ConnS, "Connection %s: Memory allocation failure: [%d] %s", ConnS->Name, errno, strerror(errno));
      return;
    }
    ConnS->RecvBuffer = RecvBufferPT;
    RecvBufferPT += OldLen;
    strcpy(RecvBufferPT, RecvBuffer);
  }
  while (Result >= RECVBUFFERLEN);

  if (Conn_IsSentQuit(ConnS)) { return; }

  conn_parser(ConnS);

}

/* CONN_SEND FUNCTION - JONAS (01.07.2000) */

void conn_send(struct Conn_Struct *ConnS) {

  char *SendBufferPT = NULL;
  char SendBuffer[SENDBUFFERLEN+1] = "";
  unsigned long int SendLen = 0;
  unsigned long int SentLen = 0;
  signed long int Result = 0;

  assert(ConnS != NULL);
  assert(Conn_IsSocket(ConnS));
  assert(ConnS->FD != FD_NONE);
  assert(ConnS->SendBuffer != NULL);

  if ((Conn_IsConnectProc(ConnS)) && (Host_IsResolved(ConnS->ResolveFlags))) {
    conn_connect(ConnS);
    if (!Conn_IsSocket(ConnS)) { return; }
  }

  for (SendBufferPT = ConnS->SendBuffer ; *SendBufferPT != 0 ; SendBufferPT += SentLen) {
    SendLen = strlen(SendBufferPT);
    if (SendLen > SENDBUFFERLEN) { SendLen = SENDBUFFERLEN; }
    memset(&SendBuffer, 0, sizeof(SendBuffer));
    strncpy(SendBuffer, SendBufferPT, SendLen);
    Result = send(ConnS->FD, SendBufferPT, SendLen, MSG_NOSIGNAL);
    if (Result <= ERROR) {
      if ((errno == EAGAIN) || (errno == EWOULDBLOCK) || (errno == EINTR) || (errno == ENOMEM) || (errno == ENOBUFS)) {
        unsigned long int Len = 0;
        client_noticealluser(ConnS->User, "Connection %s: Write error to %s(%s):%ld: [%d] %s", ConnS->Name, ConnS->ServerHostName, ConnS->ServerHostIPS, ConnS->ServerPortH, errno, strerror(errno));
        /*
         * EAGAIN/EWOULDBLOCK -- THE SOCKET IMPLEMENTATION CAN'T HANDLE MORE DATA.
         * EINTR - INTERRUPTED BY A SIGNAL.
         * ENOMEM - NO MEMORY LEFT.
         * ENOBUFS - NO BUFFER SPACE AVAILABLE.
         *
         * COPY WHATS LEFT TO THE THE START OF THE SENDBUFFER, REALLOCATE THE MEMORY AND BAIL OUT - JONAS (01.12.1999)
         *
         */
        Len = strlen(SendBufferPT) + 1;
        memmove(ConnS->SendBuffer, SendBufferPT, Len);
        SendBufferPT = realloc(ConnS->SendBuffer, Len);
        assert(SendBufferPT != NULL);
        ConnS->SendBuffer = SendBufferPT;
        return;
      }
      conn_disconnect(ConnS, "Connection %s: Write error to %s(%s):%ld: [%d] %s", ConnS->Name, ConnS->ServerHostName, ConnS->ServerHostIPS, ConnS->ServerPortH, errno, strerror(errno));
      return;
    }
    SentLen = Result;
    assert(SentLen == SendLen);
  }

  FREE(ConnS->SendBuffer);

}