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/*
FreeRTOS V8.1.2 - Copyright (C) 2014 Real Time Engineers Ltd.
All rights reserved
VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
***************************************************************************
* *
* FreeRTOS provides completely free yet professionally developed, *
* robust, strictly quality controlled, supported, and cross *
* platform software that has become a de facto standard. *
* *
* Help yourself get started quickly and support the FreeRTOS *
* project by purchasing a FreeRTOS tutorial book, reference *
* manual, or both from: http://www.FreeRTOS.org/Documentation *
* *
* Thank you! *
* *
***************************************************************************
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. Full license text is available from the following
link: http://www.freertos.org/a00114.html
1 tab == 4 spaces!
***************************************************************************
* *
* Having a problem? Start by reading the FAQ "My application does *
* not run, what could be wrong?" *
* *
* http://www.FreeRTOS.org/FAQHelp.html *
* *
***************************************************************************
http://www.FreeRTOS.org - Documentation, books, training, latest versions,
license and Real Time Engineers Ltd. contact details.
http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
including FreeRTOS+Trace - an indispensable productivity tool, a DOS
compatible FAT file system, and our tiny thread aware UDP/IP stack.
http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High
Integrity Systems to sell under the OpenRTOS brand. Low cost OpenRTOS
licenses offer ticketed support, indemnification and middleware.
http://www.SafeRTOS.com - High Integrity Systems also provide a safety
engineered and independently SIL3 certified version for use in safety and
mission critical applications that require provable dependability.
1 tab == 4 spaces!
*/
/******************************************************************************
*
* See the following web page for essential TwoEchoClient.c usage and
* configuration details:
* http://www.FreeRTOS.org/FreeRTOS-Plus/FreeRTOS_Plus_UDP/Embedded_Ethernet_Examples/Common_Echo_Clients.shtml
*
******************************************************************************/
/* Standard includes. */
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
/* FreeRTOS includes. */
#include "FreeRTOS.h"
#include "task.h"
/* FreeRTOS+UDP includes. */
#include "FreeRTOS_UDP_IP.h"
#include "FreeRTOS_Sockets.h"
/* Small delay used between attempts to obtain a zero copy buffer. */
#define echoTINY_DELAY ( ( TickType_t ) 2 )
/* The echo tasks create a socket, send out a number of echo requests
(listening for each echo reply), then close the socket again before
starting over. This delay is used between each iteration to ensure the
network does not get too congested. */
#define echoLOOP_DELAY ( ( TickType_t ) 250 / portTICK_RATE_MS )
#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. */
#define echoMARK_SEND_IN_TRACE_BUFFER( x ) vTraceUserEvent( x )
traceLabel xZeroCopySendEvent, xZeroCopyReceiveEvent;
#else
/* When the trace recorder code is not included just #define away the call
to post the user event. */
#define echoMARK_SEND_IN_TRACE_BUFFER( x )
#define xZeroCopySendEvent 0
#define xZeroCopyReceiveEvent 0
#endif
/* The echo server is assumed to be on port 7, which is the standard echo
protocol port. */
#define echoECHO_PORT ( 7 )
/*
* Uses a socket to send data to, then receive data from, the standard echo
* port number 7. prvEchoClientTask() uses the standard interface.
* prvZeroCopyEchoClientTask() uses the zero copy interface.
*/
static void prvEchoClientTask( void *pvParameters );
static void prvZeroCopyEchoClientTask( void *pvParameters );
/* The receive timeout is set shorter when the windows simulator is used
because simulated time is slower than real time. */
#ifdef _WINDOWS_
const TickType_t xReceiveTimeOut = 50 / portTICK_RATE_MS;
#else
const TickType_t xReceiveTimeOut = 500 / portTICK_RATE_MS;
#endif
/*-----------------------------------------------------------*/
void vStartEchoClientTasks( uint16_t usTaskStackSize, UBaseType_t uxTaskPriority )
{
/* Create the echo client task that does not use the zero copy interface. */
xTaskCreate( prvEchoClientTask, /* The function that implements the task. */
"Echo0", /* Just a text name for the task to aid debugging. */
usTaskStackSize, /* The stack size is defined in FreeRTOSIPConfig.h. */
NULL, /* The task parameter, not used in this case. */
uxTaskPriority, /* The priority assigned to the task is defined in FreeRTOSConfig.h. */
NULL ); /* The task handle is not used. */
/* Create the echo client task that does use the zero copy interface. */
xTaskCreate( prvZeroCopyEchoClientTask, /* The function that implements the task. */
"Echo1", /* Just a text name for the task to aid debugging. */
usTaskStackSize, /* The stack size is defined in FreeRTOSIPConfig.h. */
NULL, /* The task parameter, not used in this case. */
uxTaskPriority, /* The priority assigned to the task is defined in FreeRTOSConfig.h. */
NULL ); /* The task handle is not used. */
}
/*-----------------------------------------------------------*/
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 );
}
}
/*-----------------------------------------------------------*/
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 );
}
}
/*-----------------------------------------------------------*/
|