FreeRTOS-Plus/Demo_Projects_Using_FreeRTOS_Simulator/FreeRTOS_Plus_CLI_with_Trace/UDPCommandServer.c

/*
    FreeRTOS V7.1.1 - Copyright (C) 2012 Real Time Engineers Ltd.


    ***************************************************************************
     *                                                                       *
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     *    Complete, revised, and edited pdf reference manuals are also       *
     *    available.                                                         *
     *                                                                       *
     *    Purchasing FreeRTOS documentation will not only help you, by       *
     *    ensuring you get running as quickly as possible and with an        *
     *    in-depth knowledge of how to use FreeRTOS, it will also help       *
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     *    professional grade, cross platform, de facto standard solutions    *
     *    for microcontrollers - completely free of charge!                  *
     *                                                                       *
     *    >>> See http://www.FreeRTOS.org/Documentation for details. <<<     *
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     *    Thank you for using FreeRTOS, and thank you for your support!      *
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    ***************************************************************************


    This file is part of the FreeRTOS distribution.

    FreeRTOS is free software; you can redistribute it and/or modify it under
    the terms of the GNU General Public License (version 2) as published by the
    Free Software Foundation AND MODIFIED BY the FreeRTOS exception.
    >>>NOTE<<< The modification to the GPL is included to allow you to
    distribute a combined work that includes FreeRTOS without being obliged to
    provide the source code for proprietary components outside of the FreeRTOS
    kernel.  FreeRTOS 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 and the FreeRTOS license exception along with FreeRTOS; if not it
    can be viewed here: http://www.freertos.org/a00114.html and also obtained
    by writing to Richard Barry, contact details for whom are available on the
    FreeRTOS WEB site.

    1 tab == 4 spaces!
    
    ***************************************************************************
     *                                                                       *
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    ***************************************************************************

    
    http://www.FreeRTOS.org - Documentation, training, latest information, 
    license and contact details.
    
    http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
    including FreeRTOS+Trace - an indispensable productivity tool.

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    the code with commercial support, indemnification, and middleware, under 
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    provide a safety engineered and independently SIL3 certified version under 
    the SafeRTOS brand: http://www.SafeRTOS.com.
*/

#pragma comment( lib, "ws2_32.lib" )

/* Win32 includes. */
#include <WinSock2.h>

/* FreeRTOS includes. */
#include "FreeRTOS.h"
#include "task.h"

/* FreeRTOS+CLI includes. */
#include "FreeRTOS_CLI.h"

/* Dimensions the buffer into which input characters are placed. */
#define cmdMAX_INPUT_SIZE	60

/* Dimensions the buffer into which string outputs can be placed. */
#define cmdMAX_OUTPUT_SIZE	1024

/* Dimensions the buffer passed to the recvfrom() call. */
#define cmdSOCKET_INPUT_BUFFER_SIZE 60

/*
 * Open and configure the UDP socket.
 */
static SOCKET prvOpenUDPSocket( void );

/*-----------------------------------------------------------*/

/* 
 * Task that provides the input and output for the FreeRTOS+CLI command
 * interpreter.  In this case a UDP port is used.  See the URL in the comments
 * within main.c for the location of the online documentation.
 */
void vUDPCommandInterpreterTask( void *pvParameters )
{
long lBytes, lByte;
signed char cInChar, cInputIndex = 0;
static signed char cInputString[ cmdMAX_INPUT_SIZE ], cOutputString[ cmdMAX_OUTPUT_SIZE ], cLocalBuffer[ cmdSOCKET_INPUT_BUFFER_SIZE ];
portBASE_TYPE xMoreDataToFollow;
volatile int iErrorCode = 0;
struct sockaddr_in xClient;
int xClientAddressLength = sizeof( struct sockaddr_in );
SOCKET xSocket;

	/* Just to prevent compiler warnings. */
	( void ) pvParameters;

	/* Attempt to open the socket. */
	xSocket = prvOpenUDPSocket();

	if( xSocket != INVALID_SOCKET )
	{
		for( ;; )
		{
			/* Wait for incoming data on the opened socket. */
			lBytes = recvfrom( xSocket, cLocalBuffer, sizeof( cLocalBuffer ), 0, ( struct sockaddr * ) &xClient, &xClientAddressLength );

			if( lBytes == SOCKET_ERROR )
			{
				/* Something went wrong, but it is not handled by this simple
				example. */
				iErrorCode = WSAGetLastError();
			}
			else
			{				
				/* Process each received byte in turn. */
				lByte = 0;
				while( lByte < lBytes )
				{
					/* The next character in the input buffer. */
					cInChar = cLocalBuffer[ lByte ];
					lByte++;

					/* Newline characters are taken as the end of the command
					string. */
					if( cInChar == '\n' )
					{
						/* Process the input string received prior to the 
						newline. */
						do
						{
							/* Pass the string to FreeRTOS+CLI. */
							xMoreDataToFollow = FreeRTOS_CLIProcessCommand( cInputString, cOutputString, cmdMAX_OUTPUT_SIZE );
							
							/* Send the output generated by the command's
							implementation. */
							sendto( xSocket, cOutputString,  strlen( cOutputString ), 0, ( SOCKADDR * ) &xClient, xClientAddressLength );

						} while( xMoreDataToFollow != pdFALSE ); /* Until the command does not generate any more output. */

						/* All the strings generated by the command processing 
						have been sent.  Clear the input string ready to receive 
						the next command. */
						cInputIndex = 0;
						memset( cInputString, 0x00, cmdMAX_INPUT_SIZE );
						
						/* Transmit a spacer, just to make the command console
						easier to read. */
						sendto( xSocket, "\r\n",  strlen( "\r\n" ), 0, ( SOCKADDR * ) &xClient, xClientAddressLength );
					}
					else
					{
						if( cInChar == '\r' )
						{
							/* Ignore the character.  Newlines are used to 
							detect the end of the input string. */
						}
						else if( cInChar == '\b' )
						{
							/* Backspace was pressed.  Erase the last character 
							in the string - if any. */
							if( cInputIndex > 0 )
							{
								cInputIndex--;
								cInputString[ cInputIndex ] = '\0';
							}
						}
						else
						{
							/* A character was entered.  Add it to the string
							entered so far.  When a \n is entered the complete
							string will be passed to the command interpreter. */
							if( cInputIndex < cmdMAX_INPUT_SIZE )
							{
								cInputString[ cInputIndex ] = cInChar;
								cInputIndex++;
							}
						}
					}
				}
			}
		} 
	}
	else
	{
		/* The socket could not be opened. */
		vTaskDelete( NULL );
	}
}
/*-----------------------------------------------------------*/

static SOCKET prvOpenUDPSocket( void )
{
WSADATA xWSAData;
WORD wVersionRequested;
struct sockaddr_in xServer;
SOCKET xSocket = INVALID_SOCKET;

	wVersionRequested = MAKEWORD( 2, 2 );

	/* Prepare to use WinSock. */
	if( WSAStartup( wVersionRequested, &xWSAData ) != 0 )
	{
		fprintf( stderr, "Could not open Windows connection.\n" );
	}
	else
	{
		xSocket = socket( AF_INET, SOCK_DGRAM, 0 );
		if( xSocket == INVALID_SOCKET)
		{
			fprintf( stderr, "Could not create socket.\n" );
			WSACleanup();
		}
		else
		{
			/* Zero out the server structure. */
			memset( ( void * ) &xServer, 0x00, sizeof( struct sockaddr_in ) );

			/* Set family and port. */
			xServer.sin_family = AF_INET;
			xServer.sin_port = htons( configUDP_CLI_PORT_NUMBER );

			/* Assign the loopback address */
			xServer.sin_addr.S_un.S_un_b.s_b1 = 127;
			xServer.sin_addr.S_un.S_un_b.s_b2 = 0;
			xServer.sin_addr.S_un.S_un_b.s_b3 = 0;
			xServer.sin_addr.S_un.S_un_b.s_b4 = 1;

			/* Bind the address to the socket. */
			if( bind( xSocket, ( struct sockaddr * ) &xServer, sizeof( struct sockaddr_in ) ) == -1 )
			{
				fprintf( stderr, "Could not socket to port %d.\n", configUDP_CLI_PORT_NUMBER );
				closesocket( xSocket );
				xSocket = INVALID_SOCKET;
				WSACleanup();
			}
		}
	}

	return xSocket;
}