コード例 #1
0
ssize_t nabto_read( nabto_socket_t socket,
                    uint8_t*       buf,
                    size_t         len,
                    uint32_t*      addr,
                    uint16_t*      port )
{
    int res;
    struct freertos_sockaddr xAddress;
    socklen_t xAddresslen = sizeof(xAddress);

    memset( &xAddress, 0, sizeof( xAddress ) );
    res = FreeRTOS_recvfrom( socket, buf, ( int ) len , 0, &xAddress, &xAddresslen );

    if( res > 0 )
    {
        *addr = FreeRTOS_htonl( xAddress.sin_addr );
        *port = FreeRTOS_htons( xAddress.sin_port );
    }
    else
    {
        res = 0;
    }

    return res;
} 
コード例 #2
0
ファイル: exbios.c プロジェクト: notwendig/FreeRTOS-eZ80F91
static hdr_t *doRDiskReq(hdr_t *req)
{
	uint32_t io ;
	
	hdr_t	*rsp = 0;
	pdutype_t cmd = req->cmdid | RDSK_Response;
	
	req->seqnz = sequenz;
	io = FreeRTOS_sendto( xSocketRDisk, req, req->pdusz, 0, &xRDiskAddress, sizeof(xRDiskAddress));

	if(io == req->pdusz)
	{
		struct freertos_sockaddr xFrom;
		socklen_t xFromLength;
		xFromLength = sizeof(xFrom);
		
		do {
			io = FreeRTOS_recvfrom( xSocketRDisk, &rsp, 0, FREERTOS_ZERO_COPY, &xFrom, &xFromLength );
		} while( io == -pdFREERTOS_ERRNO_EWOULDBLOCK);
		
		if(	io >= sizeof(hdr_t) && 
			io == rsp->pdusz && 
			rsp->seqnz == (uint16_t) ~sequenz && 
			(pdutype_t)(rsp->cmdid & ~RDSK_ErrorFlag) == cmd)
		{
			sequenz++;
		}
		else
		{
			FreeRTOS_ReleaseUDPPayloadBuffer( ( void * ) rsp);
			rsp = 0;
		}
	}
	return rsp;
}
static void prvSimpleZeroCopyServerTask( void *pvParameters )
{
int32_t lBytes;
uint8_t *pucUDPPayloadBuffer;
struct freertos_sockaddr xClient, xBindAddress;
uint32_t xClientLength = sizeof( xClient ), ulIPAddress;
xSocket_t xListeningSocket;

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

	/* Attempt to open the socket. */
	xListeningSocket = FreeRTOS_socket( FREERTOS_AF_INET, FREERTOS_SOCK_DGRAM, FREERTOS_IPPROTO_UDP );
	configASSERT( xListeningSocket != FREERTOS_INVALID_SOCKET );

	/* This test receives data sent from a different port on the same IP address.
	Obtain the nodes IP address.  Configure the freertos_sockaddr structure with
	the address being bound to.  The strange casting is to try and remove
	compiler warnings on 32 bit machines.  Note that this task is only created
	after the network is up, so the IP address is valid here. */
	FreeRTOS_GetAddressConfiguration( &ulIPAddress, NULL, NULL, NULL );
	xBindAddress.sin_addr = ulIPAddress;
	xBindAddress.sin_port = ( uint16_t ) ( ( uint32_t ) pvParameters ) & 0xffffUL;
	xBindAddress.sin_port = FreeRTOS_htons( xBindAddress.sin_port );

	/* Bind the socket to the port that the client task will send to. */
	FreeRTOS_bind( xListeningSocket, &xBindAddress, sizeof( xBindAddress ) );

	for( ;; )
	{
		/* Receive data on the socket.  ulFlags has the zero copy bit set
		(FREERTOS_ZERO_COPY) indicating to the stack that a reference to the
		received data should be passed out to this task using the second
		parameter to the FreeRTOS_recvfrom() call.  When this is done the
		IP stack is no longer responsible for releasing the buffer, and
		the task *must* return the buffer to the stack when it is no longer
		needed.  By default the block time is portMAX_DELAY. */
		lBytes = FreeRTOS_recvfrom( xListeningSocket, ( void * ) &pucUDPPayloadBuffer, 0, FREERTOS_ZERO_COPY, &xClient, &xClientLength );

		/* It is expected to receive one more byte than the string length as
		the NULL terminator is also transmitted. */
		configASSERT( lBytes == ( ( portBASE_TYPE ) strlen( ( const char * ) pucUDPPayloadBuffer ) + 1 ) );

		/* Print the received characters. */
		if( lBytes > 0 )
		{
			vOutputString( ( char * ) pucUDPPayloadBuffer );
		}

		if( lBytes >= 0 )
		{
			/* The buffer *must* be freed once it is no longer needed. */
			FreeRTOS_ReleaseUDPPayloadBuffer( pucUDPPayloadBuffer );
		}
	}
}
static void prvSimpleServerTask( void *pvParameters )
{
long lBytes;
uint8_t cReceivedString[ 60 ];
struct freertos_sockaddr xClient, xBindAddress;
uint32_t xClientLength = sizeof( xClient );
xSocket_t xListeningSocket;

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

	/* Attempt to open the socket. */
	xListeningSocket = FreeRTOS_socket( FREERTOS_AF_INET, FREERTOS_SOCK_DGRAM, FREERTOS_IPPROTO_UDP );
	configASSERT( xListeningSocket != FREERTOS_INVALID_SOCKET );

	/* This test receives data sent from a different port on the same IP
	address.  Configure the freertos_sockaddr structure with the address being
	bound to.  The strange casting is to try and remove	compiler warnings on 32
	bit machines.  Note that this task is only created after the network is up,
	so the IP address is valid here. */
	xBindAddress.sin_port = ( uint16_t ) ( ( uint32_t ) pvParameters ) & 0xffffUL;
	xBindAddress.sin_port = FreeRTOS_htons( xBindAddress.sin_port );

	/* Bind the socket to the port that the client task will send to. */
	FreeRTOS_bind( xListeningSocket, &xBindAddress, sizeof( xBindAddress ) );

	for( ;; )
	{
		/* Zero out the receive array so there is NULL at the end of the string
		when it is printed out. */
		memset( cReceivedString, 0x00, sizeof( cReceivedString ) );

		/* Receive data on the socket.  ulFlags is zero, so the zero copy option
		is not set and the received data is copied into the buffer pointed to by
		cReceivedString.  By default the block time is portMAX_DELAY.
		xClientLength is not actually used by FreeRTOS_recvfrom(), but is set
		appropriately in case future versions do use it. */
		lBytes = FreeRTOS_recvfrom( xListeningSocket, cReceivedString, sizeof( cReceivedString ), 0, &xClient, &xClientLength );

		/* Print the received characters. */
		if( lBytes > 0 )
		{
			vOutputString( ( char * ) cReceivedString );
		}

		/* Error check. */
		configASSERT( lBytes == ( portBASE_TYPE ) strlen( ( const char * ) cReceivedString ) );
	}
}
コード例 #5
0
ファイル: FreeRTOS_DHCP.c プロジェクト: DuinOS/FreeRTOS
static portBASE_TYPE prvProcessDHCPReplies( uint8_t ucExpectedMessageType, xMACAddress_t *pxMACAddress, xNetworkAddressingParameters_t *pxNetworkAddressing )
{
uint8_t *pucUDPPayload, *pucLastByte;
struct freertos_sockaddr xClient;
uint32_t xClientLength = sizeof( xClient );
int32_t lBytes;
xDHCPMessage_t *pxDHCPMessage;
uint8_t *pucByte, ucOptionCode, ucLength;
uint32_t ulProcessed;
portBASE_TYPE xReturn = pdFALSE;
const uint32_t ulMandatoryOptions = 2; /* DHCP server address, and the correct DHCP message type must be present in the options. */

	lBytes = FreeRTOS_recvfrom( xDHCPSocket, ( void * ) &pucUDPPayload, 0, FREERTOS_ZERO_COPY, &xClient, &xClientLength );

	if( lBytes > 0 )
	{
		/* Map a DHCP structure onto the received data. */
		pxDHCPMessage = ( xDHCPMessage_t * ) ( pucUDPPayload );

		/* Sanity check. */
		if( ( pxDHCPMessage->ulDHCPCookie == dhcpCOOKIE ) && ( pxDHCPMessage->ucOpcode == dhcpREPLY_OPCODE ) && ( pxDHCPMessage->ulTransactionID == ulTransactionId ) )
		{
			if( memcmp( ( void * ) &( pxDHCPMessage->ucClientHardwareAddress ), ( void * ) pxMACAddress, sizeof( xMACAddress_t ) ) == 0 )
			{
				/* None of the essential options have been processed yet. */
				ulProcessed = 0;

				/* Walk through the options until the dhcpOPTION_END_BYTE byte
				is found, taking care not to walk off the end of the options. */
				pucByte = &( pxDHCPMessage->ucFirstOptionByte );
				pucLastByte = &( pucUDPPayload[ lBytes - dhcpMAX_OPTION_LENGTH_OF_INTEREST ] );
				while( ( *pucByte != dhcpOPTION_END_BYTE ) && ( pucByte < pucLastByte ) )
				{
					ucOptionCode = *pucByte;
					pucByte++;
					ucLength = *pucByte;
					pucByte++;

					switch( ucOptionCode )
					{
						case dhcpMESSAGE_TYPE_OPTION_CODE	:

							if( *pucByte == ucExpectedMessageType )
							{
								/* The message type is the message type the
								state machine is expecting. */
								ulProcessed++;
							}
							else if( *pucByte == dhcpMESSAGE_TYPE_NACK )
							{
								if( ucExpectedMessageType == dhcpMESSAGE_TYPE_ACK )
								{
									/* Start again. */
									eDHCPState = eWaitingSendFirstDiscover;
								}
							}
							else
							{
								/* Don't process other message types. */
							}
							break;

						case dhcpSUBNET_MASK_OPTION_CODE :

							if( ucLength == sizeof( uint32_t ) )
							{
								memcpy( ( void * ) &( pxNetworkAddressing->ulNetMask ), ( void * ) pucByte, ( size_t ) ucLength );
							}
							break;

						case dhcpGATEWAY_OPTION_CODE :

							if( ucLength == sizeof( uint32_t ) )
							{
								/* ulProcessed is not incremented in this case
								because the gateway is not essential. */
								memcpy( ( void * ) &( pxNetworkAddressing->ulGatewayAddress ), ( void * ) pucByte, ( size_t ) ucLength );
							}
							break;

						case hdcpDNS_SERVER_OPTIONS_CODE :

							/* ulProcessed is not incremented in this case
							because the DNS server is not essential.  Only the
							first DNS server address is taken. */
							memcpy( ( void * ) &( pxNetworkAddressing->ulDNSServerAddress ), ( void * ) pucByte, sizeof( uint32_t ) );
							break;

						case dhcpSERVER_IP_ADDRESS_OPTION_CODE :

							if( ucLength == sizeof( uint32_t ) )
							{
								if( ucExpectedMessageType == dhcpMESSAGE_TYPE_OFFER )
								{
									/* Offers state the replying server. */
									ulProcessed++;
									memcpy( ( void * ) &ulDHCPServerAddress, ( void * ) pucByte, ( size_t ) ucLength );
								}
								else
								{
									/* The ack must come from the expected server. */
									if( memcmp( ( void * ) &ulDHCPServerAddress, ( void * ) pucByte, ( size_t ) ucLength ) == 0 )
									{
										ulProcessed++;
									}
								}
							}
							break;

						case dhcpLEASE_TIME_OPTION_CODE :

							if( ucLength == sizeof( &ulLeaseTime ) )
							{
								/* ulProcessed is not incremented in this case
								because the lease time is not essential. */
								memcpy( ( void * ) &ulLeaseTime, ( void * ) pucByte, ( size_t ) ucLength );
								ulLeaseTime = FreeRTOS_ntohl( ulLeaseTime );

								/* Convert the lease time to milliseconds
								(*1000) then ticks (/portTICK_RATE_MS). */
								ulLeaseTime *= ( 1000UL / portTICK_RATE_MS );

								/* Divide the lease time to ensure a renew
								request is sent before the lease actually
								expires. */
								ulLeaseTime >>= 1UL;
							}
							break;

						default :

							/* Not interested in this field. */

							break;
					}

					/* Jump over the data to find the next option code. */
					if( ucLength == 0 )
					{
						break;
					}
					else
					{
						pucByte += ucLength;
					}
				}

				/* Were all the mandatory options received? */
				if( ulProcessed == ulMandatoryOptions )
				{
					ulOfferedIPAddress = pxDHCPMessage->ulYourIPAddress_yiaddr;
					xReturn = pdPASS;
				}
			}
コード例 #6
0
ファイル: UDPCommandServer.c プロジェクト: peterliu2/FreeRTOS
/*
 * 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 ];
    BaseType_t xMoreDataToFollow;
    struct freertos_sockaddr xClient;
    socklen_t xClientAddressLength = 0; /* This is required as a parameter to maintain the sendto() Berkeley sockets API - but it is not actually used so can take any value. */
    xSocket_t xSocket;
    extern const uint8_t ucIPAddress[ 4 ];
    extern const uint8_t ucMACAddress[ 6 ];

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

    /* Attempt to open the socket.  The port number is passed in the task
    parameter.  The strange casting is to remove compiler warnings on 32-bit
    machines. */
    xSocket = prvOpenUDPServerSocket( ( uint16_t ) ( ( uint32_t ) pvParameters ) & 0xffffUL );

    if( xSocket != FREERTOS_INVALID_SOCKET ) {
        for( ;; ) {
            /* Wait for incoming data on the opened socket. */
            lBytes = FreeRTOS_recvfrom( xSocket, ( void * ) cLocalBuffer, sizeof( cLocalBuffer ), 0, &xClient, &xClientAddressLength );

            if( lBytes != FREERTOS_SOCKET_ERROR ) {
                /* 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. */
                            FreeRTOS_sendto( xSocket, cOutputString,  strlen( cOutputString ), 0, &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. */
                        FreeRTOS_sendto( xSocket, "\r\n",  strlen( "\r\n" ), 0, &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 );
    }
}
コード例 #7
0
static void prvZeroCopyEchoClientTask( void *pvParameters )
{
xSocket_t xSocket;
struct freertos_sockaddr xEchoServerAddress;
static char cTxString[ 40 ];
int32_t lLoopCount = 0UL;
volatile uint32_t ulRxCount = 0UL, ulTxCount = 0UL;
uint32_t xAddressLength = sizeof( xEchoServerAddress );
int32_t lReturned;
uint8_t *pucUDPPayloadBuffer;

const int32_t lMaxLoopCount = 50;
const char * const pcStringToSend = "Zero copy message number";
/* The buffer is large enough to hold the string, a number, and the string terminator. */
const size_t xBufferLength = strlen( pcStringToSend ) + 15;

	#if ipconfigINCLUDE_EXAMPLE_FREERTOS_PLUS_TRACE_CALLS == 1
	{
		/* When the trace recorder code is included user events are generated to
		mark the sending and receiving of the echoed data (only in the zero copy
		task). */
		xZeroCopySendEvent = xTraceOpenLabel( "ZeroCopyTx" );
		xZeroCopyReceiveEvent = xTraceOpenLabel( "ZeroCopyRx" );
	}
	#endif /* ipconfigINCLUDE_EXAMPLE_FREERTOS_PLUS_TRACE_CALLS */

	/* Remove compiler warning about unused parameters. */
	( void ) pvParameters;

	/* Delay for a little while to ensure the task is out of synch with the
	other echo task implemented above. */
	vTaskDelay( echoLOOP_DELAY >> 1 );

	/* Echo requests are sent to the echo server.  The address of the echo
	server is configured by the constants configECHO_SERVER_ADDR0 to
	configECHO_SERVER_ADDR3 in FreeRTOSConfig.h. */
	xEchoServerAddress.sin_port = FreeRTOS_htons( echoECHO_PORT );
	xEchoServerAddress.sin_addr = FreeRTOS_inet_addr_quick( configECHO_SERVER_ADDR0,
															configECHO_SERVER_ADDR1,
															configECHO_SERVER_ADDR2,
															configECHO_SERVER_ADDR3 );

	for( ;; )
	{
		/* Create a socket. */
		xSocket = FreeRTOS_socket( FREERTOS_AF_INET, FREERTOS_SOCK_DGRAM, FREERTOS_IPPROTO_UDP );
		configASSERT( xSocket != FREERTOS_INVALID_SOCKET );

		/* Set a time out so a missing reply does not cause the task to block
		indefinitely. */
		FreeRTOS_setsockopt( xSocket, 0, FREERTOS_SO_RCVTIMEO, &xReceiveTimeOut, sizeof( xReceiveTimeOut ) );

		/* Send a number of echo requests. */
		for( lLoopCount = 0; lLoopCount < lMaxLoopCount; lLoopCount++ )
		{
			/* This task is going to send using the zero copy interface.  The
			data being sent is therefore written directly into a buffer that is
			passed by reference into the FreeRTOS_sendto() function.  First
			obtain a buffer of adequate size from the IP stack.  Although a max
			delay is used, the actual delay will be capped to
			ipconfigMAX_SEND_BLOCK_TIME_TICKS, hence the test to ensure a buffer
			was actually obtained. */
			pucUDPPayloadBuffer = ( uint8_t * ) FreeRTOS_GetUDPPayloadBuffer( xBufferLength, portMAX_DELAY );

			if( pucUDPPayloadBuffer != NULL )
			{
				/* A buffer was successfully obtained.  Create the string that is
				sent to the echo server.  Note the string is written directly
				into the buffer obtained from the IP stack. */
				sprintf( ( char * ) pucUDPPayloadBuffer, "%s %u\r\n", "Zero copy message number", ( unsigned int ) ulTxCount );

				/* Also copy the string into a local buffer so it can be compared
				with the string that is later received back from the echo server. */
				strcpy( cTxString, ( char * ) pucUDPPayloadBuffer );

				/* Pass the buffer into the send function.  ulFlags has the
				FREERTOS_ZERO_COPY bit set so the IP stack will take control of
				the	buffer, rather than copy data out of the buffer. */
				echoMARK_SEND_IN_TRACE_BUFFER( xZeroCopySendEvent );
				lReturned = FreeRTOS_sendto( 	xSocket,					/* The socket being sent to. */
												( void * ) pucUDPPayloadBuffer,	/* The buffer being passed into the IP stack. */
												strlen( cTxString ) + 1, 	/* The length of the data being sent.  Plus 1 to ensure the null terminator is part of the data. */
												FREERTOS_ZERO_COPY,			/* ulFlags with the zero copy bit is set. */
												&xEchoServerAddress,		/* Where the data is being sent. */
												sizeof( xEchoServerAddress ) );

				if( lReturned == 0 )
				{
					/* The send operation failed, so this task is still
					responsible	for the buffer obtained from the IP stack.  To
					ensure the buffer is not lost it must either be used again,
					or, as in this case, returned to the IP stack using
					FreeRTOS_ReleaseUDPPayloadBuffer().  pucUDPPayloadBuffer can
					be safely re-used to receive from the socket below once the
					buffer has been returned to the stack. */
					FreeRTOS_ReleaseUDPPayloadBuffer( ( void * ) pucUDPPayloadBuffer );
				}
				else
				{
					/* The send was successful so the IP stack is now managing
					the	buffer pointed to by pucUDPPayloadBuffer, and the IP
					stack will return the buffer once it has been sent.
					pucUDPPayloadBuffer can	be safely re-used to receive from
					the socket below. */
				}

				/* Keep a count of how many echo requests have been transmitted
				so it can be compared to the number of echo replies received.
				It would be expected to loose at least one to an ARP message the
				first time the connection is created. */
				ulTxCount++;

				/* Receive data on the socket.  ulFlags has the zero copy bit set
				(FREERTOS_ZERO_COPY) indicating to the stack that a reference to
				the	received data should be passed out to this task using the
				second parameter to the FreeRTOS_recvfrom() call.  When this is
				done the IP stack is no longer responsible for releasing the
				buffer, and	the task *must* return the buffer to the stack when
				it is no longer	needed.  By default the receive block time is
				portMAX_DELAY. */
				echoMARK_SEND_IN_TRACE_BUFFER( xZeroCopyReceiveEvent );
				lReturned = FreeRTOS_recvfrom(	xSocket,					/* The socket to receive from. */
												( void * ) &pucUDPPayloadBuffer,  /* pucUDPPayloadBuffer will be set to point to the buffer that already contains the received data. */
												0,							/* Ignored because the zero copy interface is being used. */
												FREERTOS_ZERO_COPY,			/* ulFlags with the FREERTOS_ZERO_COPY bit set. */
												&xEchoServerAddress,		/* The address from which the data was sent. */
												&xAddressLength );

				if( lReturned > 0 )
				{
					/* Compare the string sent to the echo server with the string
					received back from the echo server. */
					if( strcmp( ( char * ) pucUDPPayloadBuffer, cTxString ) == 0 )
					{
						/* The strings matched. */
						ulRxCount++;
					}

					/* The buffer that contains the data passed out of the stack
					*must* be returned to the stack. */
					FreeRTOS_ReleaseUDPPayloadBuffer( pucUDPPayloadBuffer );
				}
			}
		}

		/* Pause for a short while to ensure the network is not too
		congested. */
		vTaskDelay( echoLOOP_DELAY );

		/* Close this socket before looping back to create another. */
		FreeRTOS_closesocket( xSocket );
	}
}
コード例 #8
0
static void prvEchoClientTask( void *pvParameters )
{
xSocket_t xSocket;
struct freertos_sockaddr xEchoServerAddress;
char cTxString[ 25 ], cRxString[ 25 ]; /* Make sure the stack is large enough to hold these.  Turn on stack overflow checking during debug to be sure. */
int32_t lLoopCount = 0UL;
const int32_t lMaxLoopCount = 50;
volatile uint32_t ulRxCount = 0UL, ulTxCount = 0UL;
uint32_t xAddressLength = sizeof( xEchoServerAddress );

	/* Remove compiler warning about unused parameters. */
	( void ) pvParameters;

	/* Echo requests are sent to the echo server.  The address of the echo
	server is configured by the constants configECHO_SERVER_ADDR0 to
	configECHO_SERVER_ADDR3 in FreeRTOSConfig.h. */
	xEchoServerAddress.sin_port = FreeRTOS_htons( echoECHO_PORT );
	xEchoServerAddress.sin_addr = FreeRTOS_inet_addr_quick( configECHO_SERVER_ADDR0,
															configECHO_SERVER_ADDR1,
															configECHO_SERVER_ADDR2,
															configECHO_SERVER_ADDR3 );

	for( ;; )
	{
		/* Create a socket. */
		xSocket = FreeRTOS_socket( FREERTOS_AF_INET, FREERTOS_SOCK_DGRAM, FREERTOS_IPPROTO_UDP );
		configASSERT( xSocket != FREERTOS_INVALID_SOCKET );

		/* Set a time out so a missing reply does not cause the task to block
		indefinitely. */
		FreeRTOS_setsockopt( xSocket, 0, FREERTOS_SO_RCVTIMEO, &xReceiveTimeOut, sizeof( xReceiveTimeOut ) );

		/* Send a number of echo requests. */
		for( lLoopCount = 0; lLoopCount < lMaxLoopCount; lLoopCount++ )
		{
			/* Create the string that is sent to the echo server. */
			sprintf( cTxString, "Message number %u\r\n", ( unsigned int ) ulTxCount );

			/* Send the string to the socket.  ulFlags is set to 0, so the zero
			copy interface is not used.  That means the data from cTxString is
			copied into a network buffer inside FreeRTOS_sendto(), and cTxString
			can be reused as soon as FreeRTOS_sendto() has returned.  1 is added
			to ensure the NULL string terminator is sent as part of the message. */
			FreeRTOS_sendto( xSocket,				/* The socket being sent to. */
							( void * ) cTxString,	/* The data being sent. */
							strlen( cTxString ) + 1,/* The length of the data being sent. */
							0,						/* ulFlags with the FREERTOS_ZERO_COPY bit clear. */
							&xEchoServerAddress,	/* The destination address. */
							sizeof( xEchoServerAddress ) );

			/* Keep a count of how many echo requests have been transmitted so
			it can be compared to the number of echo replies received.  It would
			be expected to loose at least one to an ARP message the first time
			the	connection is created. */
			ulTxCount++;

			/* Receive data echoed back to the socket.  ulFlags is zero, so the
			zero copy option is not being used and the received data will be
			copied into the buffer pointed to by cRxString.  xAddressLength is
			not actually used (at the time of writing this comment, anyway) by
			FreeRTOS_recvfrom(), but is set appropriately in case future
			versions do use it. */
			memset( ( void * ) cRxString, 0x00, sizeof( cRxString ) );
			FreeRTOS_recvfrom(	xSocket,				/* The socket being received from. */
								cRxString,				/* The buffer into which the received data will be written. */
								sizeof( cRxString ),	/* The size of the buffer provided to receive the data. */
								0,						/* ulFlags with the FREERTOS_ZERO_COPY bit clear. */
								&xEchoServerAddress,	/* The address from where the data was sent (the source address). */
								&xAddressLength );

			/* Compare the transmitted string to the received string. */
			if( strcmp( cRxString, cTxString ) == 0 )
			{
				/* The echo reply was received without error. */
				ulRxCount++;
			}
		};

		/* Pause for a short while to ensure the network is not too
		congested. */
		vTaskDelay( echoLOOP_DELAY );

		/* Close this socket before looping back to create another. */
		FreeRTOS_closesocket( xSocket );
	}
}
コード例 #9
0
ファイル: FreeRTOS_DNS.c プロジェクト: unnamet/Repo
static uint32_t prvGetHostByName( const char *pcHostName, TickType_t xIdentifier, TickType_t xReadTimeOut_ms )
{
struct freertos_sockaddr xAddress;
Socket_t xDNSSocket;
uint32_t ulIPAddress = 0UL;
uint8_t *pucUDPPayloadBuffer;
static uint32_t ulAddressLength;
BaseType_t xAttempt;
int32_t lBytes;
size_t xPayloadLength, xExpectedPayloadLength;
TickType_t xWriteTimeOut_ms = 100U;

#if( ipconfigUSE_LLMNR == 1 )
	BaseType_t bHasDot = pdFALSE;
#endif /* ipconfigUSE_LLMNR == 1 */

	/* If LLMNR is being used then determine if the host name includes a '.' -
	if not then LLMNR can be used as the lookup method. */
	#if( ipconfigUSE_LLMNR == 1 )
	{
		const char *pucPtr;
		for( pucPtr = pcHostName; *pucPtr; pucPtr++ )
		{
			if( *pucPtr == '.' )
			{
				bHasDot = pdTRUE;
				break;
			}
		}
	}
	#endif /* ipconfigUSE_LLMNR == 1 */

	/* Two is added at the end for the count of characters in the first
	subdomain part and the string end byte. */
	xExpectedPayloadLength = sizeof( DNSMessage_t ) + strlen( pcHostName ) + sizeof( uint16_t ) + sizeof( uint16_t ) + 2u;

	xDNSSocket = prvCreateDNSSocket();

	if( xDNSSocket != NULL )
	{
		FreeRTOS_setsockopt( xDNSSocket, 0, FREERTOS_SO_SNDTIMEO, ( void * ) &xWriteTimeOut_ms, sizeof( TickType_t ) );
		FreeRTOS_setsockopt( xDNSSocket, 0, FREERTOS_SO_RCVTIMEO, ( void * ) &xReadTimeOut_ms,  sizeof( TickType_t ) );

		for( xAttempt = 0; xAttempt < ipconfigDNS_REQUEST_ATTEMPTS; xAttempt++ )
		{
			/* Get a buffer.  This uses a maximum delay, but the delay will be
			capped to ipconfigUDP_MAX_SEND_BLOCK_TIME_TICKS so the return value
			still needs to be tested. */
			pucUDPPayloadBuffer = ( uint8_t * ) FreeRTOS_GetUDPPayloadBuffer( xExpectedPayloadLength, portMAX_DELAY );

			if( pucUDPPayloadBuffer != NULL )
			{
				/* Create the message in the obtained buffer. */
				xPayloadLength = prvCreateDNSMessage( pucUDPPayloadBuffer, pcHostName, xIdentifier );

				iptraceSENDING_DNS_REQUEST();

				/* Obtain the DNS server address. */
				FreeRTOS_GetAddressConfiguration( NULL, NULL, NULL, &ulIPAddress );

				/* Send the DNS message. */
#if( ipconfigUSE_LLMNR == 1 )
				if( bHasDot == pdFALSE )
				{
					/* Use LLMNR addressing. */
					( ( DNSMessage_t * ) pucUDPPayloadBuffer) -> usFlags = 0;
					xAddress.sin_addr = ipLLMNR_IP_ADDR;	/* Is in network byte order. */
					xAddress.sin_port = FreeRTOS_ntohs( ipLLMNR_PORT );
				}
				else
#endif
				{
					/* Use DNS server. */
					xAddress.sin_addr = ulIPAddress;
					xAddress.sin_port = dnsDNS_PORT;
				}

				ulIPAddress = 0UL;

				if( FreeRTOS_sendto( xDNSSocket, pucUDPPayloadBuffer, xPayloadLength, FREERTOS_ZERO_COPY, &xAddress, sizeof( xAddress ) ) != 0 )
				{
					/* Wait for the reply. */
					lBytes = FreeRTOS_recvfrom( xDNSSocket, &pucUDPPayloadBuffer, 0, FREERTOS_ZERO_COPY, &xAddress, &ulAddressLength );

					if( lBytes > 0 )
					{
						/* The reply was received.  Process it. */
						ulIPAddress = prvParseDNSReply( pucUDPPayloadBuffer, xIdentifier );

						/* Finished with the buffer.  The zero copy interface
						is being used, so the buffer must be freed by the
						task. */
						FreeRTOS_ReleaseUDPPayloadBuffer( ( void * ) pucUDPPayloadBuffer );

						if( ulIPAddress != 0UL )
						{
							/* All done. */
							break;
						}
					}
				}
				else
				{
					/* The message was not sent so the stack will not be
					releasing the zero copy - it must be released here. */
					FreeRTOS_ReleaseUDPPayloadBuffer( ( void * ) pucUDPPayloadBuffer );
				}
			}
		}

		/* Finished with the socket. */
		FreeRTOS_closesocket( xDNSSocket );
	}

	return ulIPAddress;
}
コード例 #10
0
ファイル: SelectServer.c プロジェクト: cjlano/freertos
static void prvMultipleSocketRxTask( void *pvParameters )
{
xSocketSet_t xFD_Set;
xSocket_t xSocket;
struct freertos_sockaddr xAddress;
uint32_t xClientLength = sizeof( struct freertos_sockaddr ), ulFirstRxPortNumber, x;
uint32_t ulReceivedValue = 0, ulExpectedValue = 0UL, ulReceivedCount[ selNUMBER_OF_SOCKETS ] = { 0 };
int32_t lBytes;
const TickType_t xRxBlockTime = 0;

	/* The number of the port the first Rx socket will be bound to is passed in
	as the task parameter.  Other port numbers used are consecutive from this. */
	ulFirstRxPortNumber = ( uint32_t ) pvParameters;

	/* Create the set of sockets that will be passed into FreeRTOS_select(). */
	xFD_Set = FreeRTOS_CreateSocketSet( selSELECT_QUEUE_SIZE );

	for( x = 0; x < selNUMBER_OF_SOCKETS; x++ )
	{
		/* Create the next Rx socket. */
		xRxSockets[ x ] = FreeRTOS_socket( FREERTOS_AF_INET, FREERTOS_SOCK_DGRAM, FREERTOS_IPPROTO_UDP );
		configASSERT( xRxSockets[ x ] );

		/* Bind to the next port number. */
		xAddress.sin_port = FreeRTOS_htons( ( uint16_t ) ( ulFirstRxPortNumber + x ) );
		FreeRTOS_bind( xRxSockets[ x ], &xAddress, sizeof( struct freertos_sockaddr ) );

		/* There should always be data available on the socket returned from
		FreeRTOS_select() so blocking on a read should not be necessary. */
		FreeRTOS_setsockopt( xRxSockets[ x ], 0, FREERTOS_SO_RCVTIMEO, &xRxBlockTime, sizeof( xRxBlockTime ) );

		/* Add the created socket to the set. */
		FreeRTOS_FD_SET( xRxSockets[ x ], xFD_Set );
	}

	for( ;; )
	{
		/* Wait for a socket from the set to become available for reading. */
		xSocket = FreeRTOS_select( xFD_Set, portMAX_DELAY );

		/* xSocket should never be NULL because FreeRTOS_select() was called
		with an indefinite delay (assuming INCLUDE_vTaskSuspend is set to 1). */
		configASSERT( xSocket );

		lBytes = FreeRTOS_recvfrom( xSocket, &( ulReceivedValue ), sizeof( uint32_t ), 0, &xAddress, &xClientLength );

		/* It is possible that the first value received will not be zero
		because the first few transmitted packets may have been dropped to
		send an ARP and then wait the ARP reply. */
		if( ulExpectedValue == 0 )
		{
			if( ulExpectedValue != ulReceivedValue )
			{
				/* Correct for packets lost to ARP traffic. */
				ulExpectedValue = ulReceivedValue;
			}
		}

		/* Data should always be available even though the block time was set
		to zero because the socket was returned from FreeRTOS_select(). */
		configASSERT( lBytes == 4 );
		configASSERT( ulReceivedValue == ulExpectedValue );

		ulExpectedValue++;

		/* Keep a record of the number of times each socket has been used so it
		can be verified (using the debugger) that they all get used. */
		for( x= 0; x < selNUMBER_OF_SOCKETS; x++ )
		{
			if( xSocket == xRxSockets[ x ] )
			{
				( ulReceivedCount[ x ] )++;
				break;
			}
		}
	}
}
コード例 #11
0
ファイル: UDPSelectServer.c プロジェクト: ttzeng/lpcopen
static void prvMultipleSocketRxTask( void *pvParameters )
{
xSocketSet_t xFD_Set;
xSocket_t xSocket;
struct freertos_sockaddr xAddress;
uint32_t xClientLength = sizeof( struct freertos_sockaddr ), ulFirstRxPortNumber, x;
uint32_t ulReceivedValue = 0, ulCount;
uint8_t ucReceivedValues[ selMAX_TX_VALUE ]; /* If the array position is pdTRUE then the corresponding value has been received. */
int32_t lBytes;
const TickType_t xRxBlockTime = 0;
BaseType_t xResult;

	/* The number of the port the first Rx socket will be bound to is passed in
	as the task parameter.  Other port numbers used are consecutive from this. */
	ulFirstRxPortNumber = ( uint32_t ) pvParameters;

	/* Create the set for sockets that will be passed into FreeRTOS_select(). */
	xFD_Set = FreeRTOS_CreateSocketSet();

	/* Create the sockets and add them to the set. */
	for( x = 0; x < selNUMBER_OF_SOCKETS; x++ )
	{
		/* Create the next Rx socket. */
		xRxSockets[ x ] = FreeRTOS_socket( FREERTOS_AF_INET, FREERTOS_SOCK_DGRAM, FREERTOS_IPPROTO_UDP );
		configASSERT( xRxSockets[ x ] != FREERTOS_INVALID_SOCKET );

		/* Bind to the next port number. */
		xAddress.sin_port = FreeRTOS_htons( ( uint16_t ) ( ulFirstRxPortNumber + x ) );
		FreeRTOS_bind( xRxSockets[ x ], &xAddress, sizeof( struct freertos_sockaddr ) );

		/* There should always be data available after FreeRTOS_select() so
		blocking on a read should not be necessary. */
		FreeRTOS_setsockopt( xRxSockets[ x ], 0, FREERTOS_SO_RCVTIMEO, &xRxBlockTime, sizeof( xRxBlockTime ) );

		/* Add the created socket to the set. */
		FreeRTOS_FD_SET( xRxSockets[ x ], xFD_Set, eSELECT_ALL );
	}

	for( ;; )
	{
		/* No values have yet been received so set each array position to
		pdFALSE.  Each expected Rx value has a corresponding array position. */
		memset( ( void * ) ucReceivedValues, pdFALSE, sizeof( ucReceivedValues ) );

		/* Wait for the other task to resume this task - indicating that it is
		about to start sending. */
		vTaskSuspend( NULL );

		/* Expect to receive selMAX_TX_VALUE values. */
		ulCount = 0;

		while( ulCount < selMAX_TX_VALUE )
		{
			/* Wait for a socket from the set to become available for
			reading. */
			xResult = FreeRTOS_select( xFD_Set, xReceiveBlockTime );

			if( xResult != 0 )
			{
				/* See which sockets have data waiting to be read. */
				for( x = 0; x < selNUMBER_OF_SOCKETS; x++ )
				{
					xSocket = xRxSockets[ x ];

					/* Find the expected value for this socket */
					if( FreeRTOS_FD_ISSET( xSocket, xFD_Set ) != 0 )
					{
						while( ( lBytes = FreeRTOS_recvfrom( xSocket, &( ulReceivedValue ), sizeof( uint32_t ), 0, &xAddress, &xClientLength ) ) > 0 )
						{
							/* Received another message. */
							ulCount++;

							/* It is always expected that the read will pass. */
							configASSERT( ( size_t ) lBytes == ( sizeof( uint32_t ) ) );

							/* Don't expect to receive anything greater than
							selMAX_TX_VALUE - 1. */
							configASSERT( ulReceivedValue < selMAX_TX_VALUE );

							/* Don't expect to receive any value twice. */
							configASSERT( ucReceivedValues[ ulReceivedValue ] != pdTRUE );
							if( ucReceivedValues[ ulReceivedValue ] != pdTRUE )
							{
								/* Mark the value as received by setting its
								index in the received array to pdTRUE. */
								ucReceivedValues[ ulReceivedValue ] = pdTRUE;
							}
							else
							{
								ulErrorOccurred = pdTRUE;
							}
						}
					}
				}
			}
			else
			{
				/* No value was received in time. */
				break;
			}
		}

		/* Were all values received? */
		if( ulCount == selMAX_TX_VALUE )
		{
			/* Check all selMAX_TX_VALUE values are present and correct
			before starting a new cycle.  It is valid for a few values at
			the beginning of the array to be missing as they may have been
			dropped for ARP messages, so start a few indexes in. */
			for( ulCount = 4; ulCount < selMAX_TX_VALUE; ulCount++ )
			{
				configASSERT( ucReceivedValues[ ulCount ] == pdTRUE );

				if( ucReceivedValues[ ulCount ] != pdTRUE )
				{
					/* The value corresponding to this array position was
					never received.  In a real application UDP is not
					reliable, but in this tightly controlled test it is
					unusual for a packet to be dropped. */
					ulErrorOccurred = pdTRUE;
				}
			}

			ulRxCycles++;
		}
		else
		{
			/* Just for viewing in the debugger. */
			ulFailedRxCycles++;
		}
	}
}
コード例 #12
0
ファイル: sntp.c プロジェクト: swichu91/stm32f4_freertos_tcp
static void SNTP_thread(void* pvp)
{
	struct sntp_c 		params;
	const TickType_t 	xReceiveTimeOut = 500;
	uint32_t			ntp_addr=0;
	struct sntp_msg		sntpmsg,sntpresponse;
	uint16_t			usBytes;
	uint32_t			addr_len = sizeof(params.xClient);



	sys_time.timezone = 1;

	params.poll_interval = SNTP_POLL_INTERVAL;

    /* Attempt to open the socket. */
    params.socket = FreeRTOS_socket( FREERTOS_AF_INET,
    									 FREERTOS_SOCK_DGRAM,
			 	 	 	 	 	 	 	 FREERTOS_IPPROTO_UDP );

    /* Set a time out so connect() will try connect over and over */
    FreeRTOS_setsockopt( params.socket,
                         0,
                         FREERTOS_SO_RCVTIMEO,
                         &xReceiveTimeOut,
                         sizeof( xReceiveTimeOut ) );

    params.xClient.sin_port = FreeRTOS_htons(SNTP_PORT_NR);

    memset(&sntpmsg,0,sizeof(sntpmsg));
    sntpmsg.li_vn_mode = SNTP_LI_NO_WARNING | SNTP_VERSION | SNTP_MODE_CLIENT;


    for(;;)
    {
        while(ntp_addr==0)
        {
        	ntp_addr=FreeRTOS_gethostbyname(SNTP_SERVER_ADDRESS_NAME); // try to connect 5 times after that returns 0
        	params.xClient.sin_addr = ntp_addr;
        }

        FreeRTOS_sendto(params.socket,&sntpmsg,sizeof(sntpmsg),0,&params.xClient,sizeof(params.xClient)); // send request

        usBytes=FreeRTOS_recvfrom(params.socket,&sntpresponse,sizeof(sntpresponse),0,&params.xClient,&addr_len); // wait for NTP's server response,blocking

        if(usBytes == SNTP_MSG_LEN)
        {
        	/* Kiss-of-death packet. Use another server or increase SNTP_POLL_INTERVAL. */
        	if(sntpresponse.stratum == SNTP_STRATUM_KOD)
        	{
        		print_gen(s_KOD);
        		params.poll_interval +=1000;

        	}
        	else if (((sntpresponse.li_vn_mode & SNTP_MODE_MASK) == SNTP_MODE_SERVER) ||
                    ((sntpresponse.li_vn_mode & SNTP_MODE_MASK) == SNTP_MODE_BROADCAST))
        	{
        		getDate(FreeRTOS_ntohl(sntpresponse.receive_timestamp[0]),&sys_time);
				#if SNTP_PRINT_LOG
        			PRINT_SYSTIME;
				#endif
        	}
        }
        else //error
        {

        }

        vTaskDelay(params.poll_interval);
    }
}
コード例 #13
0
ファイル: NTPDemo.c プロジェクト: notwendig/FreeRTOS-eZ80F91
static void prvNTPTask( void *pvParameters )
{
BaseType_t xServerIndex = 3;
struct freertos_sockaddr xAddress;
#if( ipconfigUSE_CALLBACKS != 0 )
	F_TCP_UDP_Handler_t xHandler;
#endif /* ipconfigUSE_CALLBACKS != 0 */

	xStatus = EStatusLookup;
	#if( ipconfigSOCKET_HAS_USER_SEMAPHORE != 0 ) || ( ipconfigUSE_CALLBACKS != 0 )
	{
		xNTPWakeupSem = xSemaphoreCreateBinary();
	}
	#endif

	#if( ipconfigUSE_CALLBACKS != 0 )
	{
		memset( &xHandler, '\0', sizeof ( xHandler ) );
		xHandler.pOnUdpReceive = xOnUdpReceive;
		FreeRTOS_setsockopt( xUDPSocket, 0, FREERTOS_SO_UDP_RECV_HANDLER, ( void * ) &xHandler, sizeof( xHandler ) );
	}
	#endif
	#if( ipconfigSOCKET_HAS_USER_SEMAPHORE != 0 )
	{
		FreeRTOS_setsockopt( xUDPSocket, 0, FREERTOS_SO_SET_SEMAPHORE, ( void * ) &xNTPWakeupSem, sizeof( xNTPWakeupSem ) );
	}
	#endif
	for( ; ; )
	{
		switch( xStatus )
		{
		case EStatusLookup:
			if( ( ulIPAddressFound == 0ul ) || ( ulIPAddressFound == ~0ul ) )
			{
				if( ++xServerIndex == sizeof pcTimeServers / sizeof pcTimeServers[ 0 ] )
				{
					xServerIndex = 0;
				}
				FreeRTOS_printf( ( "Looking up server '%s'\n", pcTimeServers[ xServerIndex ] ) );
				FreeRTOS_gethostbyname_a( pcTimeServers[ xServerIndex ], vDNS_callback, (void *)NULL, 1200 );
			}
			else
			{
				xStatus = EStatusAsking;
			}
			break;

		case EStatusAsking:
			{
			char pcBuf[16];

				prvNTPPacketInit( );
				xAddress.sin_addr = ulIPAddressFound;
				xAddress.sin_port = FreeRTOS_htons( NTP_PORT );

				FreeRTOS_inet_ntoa( xAddress.sin_addr, pcBuf );
				FreeRTOS_printf( ( "Sending UDP message to %s:%u\n",
					pcBuf,
					FreeRTOS_ntohs( xAddress.sin_port ) ) );

				uxSendTime = xTaskGetTickCount( );
				FreeRTOS_sendto( xUDPSocket, ( void * )&xNTPPacket, sizeof( xNTPPacket ), 0, &xAddress, sizeof( xAddress ) );
			}
			break;

		case EStatusPause:
			break;

		case EStatusFailed:
			break;
		}

		#if( ipconfigUSE_CALLBACKS != 0 )
		{
			xSemaphoreTake( xNTPWakeupSem, 5000 );
		}
		#else
		{
		uint32_t xAddressSize;
		BaseType_t xReturned;
			xAddressSize = sizeof( xAddress );
			xReturned = FreeRTOS_recvfrom( xUDPSocket, ( void * ) cRecvBuffer, sizeof( cRecvBuffer ), 0, &xAddress, &xAddressSize );
			switch( xReturned )
			{
			case 0:
			case -pdFREERTOS_ERRNO_EAGAIN:
			case -pdFREERTOS_ERRNO_EINTR:
				break;
			default:
				if( xReturned < sizeof( xNTPPacket ) )
				{
					FreeRTOS_printf( ( "FreeRTOS_recvfrom: returns %ld\n", xReturned ) );
				}
				else
				{
					prvReadTime( ( struct SNtpPacket *)cRecvBuffer );
					if( xStatus != EStatusPause )
					{
						xStatus = EStatusPause;
					}
				}
				break;
			}
		}
		#endif
	}
}
コード例 #14
0
ファイル: FreeRTOS_DNS.c プロジェクト: Pinekn/freeRTOS
uint32_t FreeRTOS_gethostbyname( const uint8_t *pcHostName )
{
static uint16_t usIdentifier = 0;
struct freertos_sockaddr xAddress;
static xSocket_t xDNSSocket = NULL;
uint32_t ulIPAddress = 0UL;
uint8_t *pucUDPPayloadBuffer;
static uint32_t ulAddressLength;
portBASE_TYPE xAttempt;
int32_t lBytes;
size_t xPayloadLength;
const size_t xExpectedPayloadLength = sizeof( xDNSMessage_t ) + strlen( ( const char * const ) pcHostName ) + sizeof( uint16_t ) + sizeof( uint16_t ) + 2; /* Two for the count of characters in the first subdomain part, and the string end byte */

	if( xDNSSocket == NULL )
	{
		xDNSSocket = prvCreateDNSSocket();
	}

	if( xDNSSocket != NULL )
	{
		/* Generate a unique identifier for this query. */
		usIdentifier++;

		for( xAttempt = 0; xAttempt < dnsMAX_REQUEST_ATTEMPTS; xAttempt++ )
		{
			/* Get a buffer.  This uses a maximum delay, but the delay will be
			capped to ipconfigMAX_SEND_BLOCK_TIME_TICKS so the return value
			still needs to be tested. */
			pucUDPPayloadBuffer = ( uint8_t * ) FreeRTOS_GetUDPPayloadBuffer( xExpectedPayloadLength, portMAX_DELAY );
			if( pucUDPPayloadBuffer != NULL )
			{
				/* Create the message in the obtained buffer. */
				xPayloadLength = prvCreateDNSMessage( pucUDPPayloadBuffer, pcHostName, usIdentifier );
				iptraceSENDING_DNS_REQUEST();

				/* Obtain the DNS server address. */
				FreeRTOS_GetAddressConfiguration( NULL, NULL, NULL, &ulIPAddress );

				/* Send the DNS message. */
				xAddress.sin_addr = ulIPAddress;
				xAddress.sin_port = dnsDNS_PORT;
				ulIPAddress = 0;

				if( FreeRTOS_sendto( xDNSSocket, pucUDPPayloadBuffer, xPayloadLength, FREERTOS_ZERO_COPY, &xAddress, sizeof( xAddress ) ) != 0 )
				{
					/* Wait for the reply. */
					lBytes = FreeRTOS_recvfrom( xDNSSocket, &pucUDPPayloadBuffer, 0, FREERTOS_ZERO_COPY, &xAddress, &ulAddressLength );

					if( lBytes > 0 )
					{
						/* The reply was received.  Process it. */
						ulIPAddress = prvParseDNSReply( pucUDPPayloadBuffer, usIdentifier );

						/* Finished with the buffer.  The zero copy interface
						is being used, so the buffer must be freed by the
						task. */
						FreeRTOS_ReleaseUDPPayloadBuffer( ( void * ) pucUDPPayloadBuffer );

						if( ulIPAddress != 0 )
						{
							/* All done. */
							break;
						}
					}
				}
				else
				{
					/* The message was not sent so the stack will not be
					releasing the zero copy - it must be released here. */
					FreeRTOS_ReleaseUDPPayloadBuffer( ( void * ) pucUDPPayloadBuffer );
				}
			}
		}
	}

	return ulIPAddress;
}