#include <Windows.h>

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <conio.h>

#define  MAX_XMT  128
#define  MAX_RCV  128

#define  CARRIAGE_RETURN  0x0D
#define  LINE_FEED        0x0A

#define  SERIAL_WAIT    0
#define  SERIAL_RCV_1   1
#define  SERIAL_RCV_2   2


main( int argc , char *argv[] )

   {
   HANDLE    hComDev1 , hComDev2 ;
   COMSTAT   ComStat1 , ComStat2 ;
   ULONG     dwError1 , dwError2 ;
   ULONG     nToRead1 , nToRead2 , nActuallyRead1 , nActuallyRead2 ;
   int       iPort1 , iPort2 ;
   long      lSpeed ;
   UCHAR     in1[MAX_RCV] , in2[MAX_RCV] ;
   char      stmp[16] ;
   ULONG     i ;
   int       currentPort ;
   int       port_a_state , port_b_state ;

   char      szPort1[8] , szPort2[8] ;
   FILE      *fp ;

   DCB       dcbSerialParams = {0} ;

   printf("\nSCADAmetrics Dual Serial Port Snooper III\n\n");
   if ( argc != 4 )
      {
      printf("Incorrect Number of Command-Line Parameters: %d\n",argc);
      printf("Usage: Snooper3.exe COMa COMb baud\n");
      return(0);
      }

   // lSpeed       = 9600L ;
   lSpeed       = atol( argv[3] ) ;

   currentPort  =    1 ;
   port_a_state = SERIAL_WAIT ;
   port_b_state = SERIAL_WAIT ;
   fp           = NULL ;


   // Setup COMa...
   // =============
   iPort1   = atoi( argv[1] ) ;
   sprintf( szPort1 , "COM%d" , iPort1 ) ;

   hComDev1 = CreateFile(
                          szPort1 ,
                          GENERIC_READ | GENERIC_WRITE ,
                          0 ,
                          0 ,
                          OPEN_EXISTING ,
                          FILE_ATTRIBUTE_NORMAL ,
                          0 ) ;


   if ( hComDev1 != INVALID_HANDLE_VALUE )
      {
      dcbSerialParams.DCBlength = sizeof(dcbSerialParams);
      if ( GetCommState(hComDev1,&dcbSerialParams) )
         {
         switch (lSpeed )
            {
            case 1200L :
               {
               dcbSerialParams.BaudRate=CBR_1200;
               break ;
               }
            case 2400L :
               {
               dcbSerialParams.BaudRate=CBR_2400;
               break ;
               }
            case 4800L :
               {
               dcbSerialParams.BaudRate=CBR_4800;
               break ;
               }
            case 9600L :
               {
               dcbSerialParams.BaudRate=CBR_9600;
               break ;
               }
            case 19200L :
               {
               dcbSerialParams.BaudRate=CBR_19200;
               break ;
               }
            case 38400L :
               {
               dcbSerialParams.BaudRate=CBR_38400;
               break ;
               }
            case 57600L :
               {
               dcbSerialParams.BaudRate=CBR_57600;
               break ;
               }
            default :
               {
               dcbSerialParams.BaudRate=CBR_9600;
               break ;
               }
            }
         dcbSerialParams.ByteSize=8;
         dcbSerialParams.StopBits=ONESTOPBIT;
         dcbSerialParams.Parity=NOPARITY;
         if (!SetCommState(hComDev1, &dcbSerialParams))
            {
            printf("Error setting COMa state\r\n");
            return(0);
            }
         }
      }
   else
      {
      printf("Error opening COMa.\r\n");
      return(0);
      }


   
   // Setup COMb...
   // =============
   iPort2   = atoi( argv[2] ) ;
   sprintf( szPort2 , "COM%d" , iPort2 ) ;

   hComDev2 = CreateFile(
                          szPort2 ,
                          GENERIC_READ | GENERIC_WRITE ,
                          0 ,
                          0 ,
                          OPEN_EXISTING ,
                          FILE_ATTRIBUTE_NORMAL ,
                          0 ) ;


   if ( hComDev2 != INVALID_HANDLE_VALUE )
      {
      dcbSerialParams.DCBlength = sizeof(dcbSerialParams);
      if ( GetCommState(hComDev2,&dcbSerialParams) )
         {
         switch (lSpeed )
            {
            case 1200L :
               {
               dcbSerialParams.BaudRate=CBR_1200;
               break ;
               }
            case 2400L :
               {
               dcbSerialParams.BaudRate=CBR_2400;
               break ;
               }
            case 4800L :
               {
               dcbSerialParams.BaudRate=CBR_4800;
               break ;
               }
            case 9600L :
               {
               dcbSerialParams.BaudRate=CBR_9600;
               break ;
               }
            case 19200L :
               {
               dcbSerialParams.BaudRate=CBR_19200;
               break ;
               }
            case 38400L :
               {
               dcbSerialParams.BaudRate=CBR_38400;
               break ;
               }
            case 57600L :
               {
               dcbSerialParams.BaudRate=CBR_57600;
               break ;
               }
            default :
               {
               dcbSerialParams.BaudRate=CBR_9600;
               break ;
               }
            }
         dcbSerialParams.ByteSize=8;
         dcbSerialParams.StopBits=ONESTOPBIT;
         dcbSerialParams.Parity=NOPARITY;
         if (!SetCommState(hComDev2, &dcbSerialParams))
            {
            printf("Error setting COMb state\r\n");
            return(0);
            }
         }
      }
   else
      {
      printf("Error opening COMb.\r\n");
      return(0);
      }



   fp = fopen( "data.txt" , "wt" ) ;
   if ( fp==NULL )
      {
      printf("Error opening data file.\r\n");
      return(0);
      }


   while (!_kbhit())
      {
      if ( currentPort == 1 )
         {
         Sleep(10);
         ClearCommError( hComDev1 , &dwError1 , &ComStat1 ) ;
         nToRead1 = ComStat1.cbInQue ;
         if ( nToRead1 > 0 )
            {
            if ( port_a_state == SERIAL_WAIT )
               {
               port_a_state = SERIAL_RCV_1 ;
               printf("\r\n\nCOMa: ");
               fprintf(fp,"\r\n\nCOMa: ");
               }
            else
               {
               port_a_state = SERIAL_RCV_1 ;
               }
            ReadFile( hComDev1 , in1 , (DWORD)nToRead1 , &nActuallyRead1 , NULL ) ;
            for ( i=0 ; i<nActuallyRead1 ; i++ )
               {
               switch ( in1[i] )
                  {
                  default :
                     {
                     sprintf(stmp,"%02X",in1[i]);
                     }
                  }
               printf("%s ",stmp);
               fprintf(fp,"%s ",stmp);
               }

            }
         else
            {
            // No data available. Switch to COMb if timeout occurs...
            if ( port_a_state == SERIAL_WAIT )
               {
               currentPort = 2 ;
               }
            else
               {
               port_a_state++ ;
               if ( port_a_state > 3 )
                  {
                  port_a_state = SERIAL_WAIT ;
                  currentPort  = 2 ;
                  }
               }
            }
         }
      else
         {
         Sleep(10);
         ClearCommError( hComDev2 , &dwError2 , &ComStat2 ) ;
         nToRead2 = ComStat2.cbInQue ;
         if ( nToRead2 > 0 )
            {
            if ( port_b_state == SERIAL_WAIT )
               {
               port_b_state = SERIAL_RCV_1 ;
               printf("\r\n\nCOMb: ");
               fprintf(fp,"\r\n\nCOMb: ");
               }
            else
               {
               port_b_state = SERIAL_RCV_1 ;
               }
            ReadFile( hComDev2 , in2 , (DWORD)nToRead2 , &nActuallyRead2 , NULL ) ;
            for ( i=0 ; i<nActuallyRead2 ; i++ )
               {
               switch ( in2[i] )
                  {
                  default :
                     {
                     sprintf(stmp,"%02X",in2[i]);
                     }
                  }
               printf("%s ",stmp);
               fprintf(fp,"%s ",stmp);
               }
            }
         else
            {
            // No data available. Switch to COMa if timeout occurs...
            if ( port_b_state == SERIAL_WAIT )
               {
               currentPort = 1 ;
               }
            else
               {
               port_b_state++ ;
               if ( port_b_state > 3 )
                  {
                  port_b_state = SERIAL_WAIT ;
                  currentPort  = 1 ;
                  }
               }
            }
         }
      }


   fflush(fp);
   fclose(fp);

   return(1);
   }