-/*\r
- * FreeRTOS+TCP V2.0.11\r
- * Copyright (C) 2017 Amazon.com, Inc. or its affiliates. All Rights Reserved.\r
- *\r
- * Permission is hereby granted, free of charge, to any person obtaining a copy of\r
- * this software and associated documentation files (the "Software"), to deal in\r
- * the Software without restriction, including without limitation the rights to\r
- * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of\r
- * the Software, and to permit persons to whom the Software is furnished to do so,\r
- * subject to the following conditions:\r
- *\r
- * The above copyright notice and this permission notice shall be included in all\r
- * copies or substantial portions of the Software.\r
- *\r
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR\r
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS\r
- * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR\r
- * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER\r
- * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN\r
- * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.\r
- *\r
- * http://www.FreeRTOS.org\r
- * http://aws.amazon.com/freertos\r
- *\r
- * 1 tab == 4 spaces!\r
- */\r
-\r
-/******************************************************************************\r
- *\r
- * See the following web page for essential buffer allocation scheme usage and\r
- * configuration details:\r
- * http://www.FreeRTOS.org/FreeRTOS-Plus/FreeRTOS_Plus_TCP/Embedded_Ethernet_Buffer_Management.html\r
- *\r
- ******************************************************************************/\r
-\r
-/* THIS FILE SHOULD NOT BE USED IF THE PROJECT INCLUDES A MEMORY ALLOCATOR\r
-THAT WILL FRAGMENT THE HEAP MEMORY. For example, heap_2 must not be used,\r
-heap_4 can be used. */\r
-\r
-\r
-/* Standard includes. */\r
-#include <stdint.h>\r
-\r
-/* FreeRTOS includes. */\r
-#include "FreeRTOS.h"\r
-#include "task.h"\r
-#include "semphr.h"\r
-\r
-/* FreeRTOS+TCP includes. */\r
-#include "FreeRTOS_IP.h"\r
-#include "FreeRTOS_UDP_IP.h"\r
-#include "FreeRTOS_IP_Private.h"\r
-#include "NetworkInterface.h"\r
-#include "NetworkBufferManagement.h"\r
-\r
-/* The obtained network buffer must be large enough to hold a packet that might\r
-replace the packet that was requested to be sent. */\r
-#if ipconfigUSE_TCP == 1\r
- #define baMINIMAL_BUFFER_SIZE sizeof( TCPPacket_t )\r
-#else\r
- #define baMINIMAL_BUFFER_SIZE sizeof( ARPPacket_t )\r
-#endif /* ipconfigUSE_TCP == 1 */\r
-\r
-/*_RB_ This is too complex not to have an explanation. */\r
-#if defined( ipconfigETHERNET_MINIMUM_PACKET_BYTES )\r
- #define ASSERT_CONCAT_(a, b) a##b\r
- #define ASSERT_CONCAT(a, b) ASSERT_CONCAT_(a, b)\r
- #define STATIC_ASSERT(e) \\r
- ;enum { ASSERT_CONCAT(assert_line_, __LINE__) = 1/(!!(e)) }\r
-\r
- STATIC_ASSERT( ipconfigETHERNET_MINIMUM_PACKET_BYTES <= baMINIMAL_BUFFER_SIZE );\r
-#endif\r
-\r
-/* A list of free (available) NetworkBufferDescriptor_t structures. */\r
-static List_t xFreeBuffersList;\r
-\r
-/* Some statistics about the use of buffers. */\r
-static size_t uxMinimumFreeNetworkBuffers;\r
-\r
-/* Declares the pool of NetworkBufferDescriptor_t structures that are available\r
-to the system. All the network buffers referenced from xFreeBuffersList exist\r
-in this array. The array is not accessed directly except during initialisation,\r
-when the xFreeBuffersList is filled (as all the buffers are free when the system\r
-is booted). */\r
-static NetworkBufferDescriptor_t xNetworkBufferDescriptors[ ipconfigNUM_NETWORK_BUFFER_DESCRIPTORS ];\r
-\r
-/* This constant is defined as false to let FreeRTOS_TCP_IP.c know that the\r
-network buffers have a variable size: resizing may be necessary */\r
-const BaseType_t xBufferAllocFixedSize = pdFALSE;\r
-\r
-/* The semaphore used to obtain network buffers. */\r
-static SemaphoreHandle_t xNetworkBufferSemaphore = NULL;\r
-\r
-/*-----------------------------------------------------------*/\r
-\r
-BaseType_t xNetworkBuffersInitialise( void )\r
-{\r
-BaseType_t xReturn, x;\r
-\r
- /* Only initialise the buffers and their associated kernel objects if they\r
- have not been initialised before. */\r
- if( xNetworkBufferSemaphore == NULL )\r
- {\r
- xNetworkBufferSemaphore = xSemaphoreCreateCounting( ipconfigNUM_NETWORK_BUFFER_DESCRIPTORS, ipconfigNUM_NETWORK_BUFFER_DESCRIPTORS );\r
- configASSERT( xNetworkBufferSemaphore );\r
-\r
- if( xNetworkBufferSemaphore != NULL )\r
- {\r
- #if ( configQUEUE_REGISTRY_SIZE > 0 )\r
- {\r
- vQueueAddToRegistry( xNetworkBufferSemaphore, "NetBufSem" );\r
- }\r
- #endif /* configQUEUE_REGISTRY_SIZE */\r
-\r
- /* If the trace recorder code is included name the semaphore for viewing\r
- in FreeRTOS+Trace. */\r
- #if( ipconfigINCLUDE_EXAMPLE_FREERTOS_PLUS_TRACE_CALLS == 1 )\r
- {\r
- extern QueueHandle_t xNetworkEventQueue;\r
- vTraceSetQueueName( xNetworkEventQueue, "IPStackEvent" );\r
- vTraceSetQueueName( xNetworkBufferSemaphore, "NetworkBufferCount" );\r
- }\r
- #endif /* ipconfigINCLUDE_EXAMPLE_FREERTOS_PLUS_TRACE_CALLS == 1 */\r
-\r
- vListInitialise( &xFreeBuffersList );\r
-\r
- /* Initialise all the network buffers. No storage is allocated to\r
- the buffers yet. */\r
- for( x = 0; x < ipconfigNUM_NETWORK_BUFFER_DESCRIPTORS; x++ )\r
- {\r
- /* Initialise and set the owner of the buffer list items. */\r
- xNetworkBufferDescriptors[ x ].pucEthernetBuffer = NULL;\r
- vListInitialiseItem( &( xNetworkBufferDescriptors[ x ].xBufferListItem ) );\r
- listSET_LIST_ITEM_OWNER( &( xNetworkBufferDescriptors[ x ].xBufferListItem ), &xNetworkBufferDescriptors[ x ] );\r
-\r
- /* Currently, all buffers are available for use. */\r
- vListInsert( &xFreeBuffersList, &( xNetworkBufferDescriptors[ x ].xBufferListItem ) );\r
- }\r
-\r
- uxMinimumFreeNetworkBuffers = ipconfigNUM_NETWORK_BUFFER_DESCRIPTORS;\r
- }\r
- }\r
-\r
- if( xNetworkBufferSemaphore == NULL )\r
- {\r
- xReturn = pdFAIL;\r
- }\r
- else\r
- {\r
- xReturn = pdPASS;\r
- }\r
-\r
- return xReturn;\r
-}\r
-/*-----------------------------------------------------------*/\r
-\r
-uint8_t *pucGetNetworkBuffer( size_t *pxRequestedSizeBytes )\r
-{\r
-uint8_t *pucEthernetBuffer;\r
-size_t xSize = *pxRequestedSizeBytes;\r
-\r
- if( xSize < baMINIMAL_BUFFER_SIZE )\r
- {\r
- /* Buffers must be at least large enough to hold a TCP-packet with\r
- headers, or an ARP packet, in case TCP is not included. */\r
- xSize = baMINIMAL_BUFFER_SIZE;\r
- }\r
-\r
- /* Round up xSize to the nearest multiple of N bytes,\r
- where N equals 'sizeof( size_t )'. */\r
- if( ( xSize & ( sizeof( size_t ) - 1u ) ) != 0u )\r
- {\r
- xSize = ( xSize | ( sizeof( size_t ) - 1u ) ) + 1u;\r
- }\r
- *pxRequestedSizeBytes = xSize;\r
-\r
- /* Allocate a buffer large enough to store the requested Ethernet frame size\r
- and a pointer to a network buffer structure (hence the addition of\r
- ipBUFFER_PADDING bytes). */\r
- pucEthernetBuffer = ( uint8_t * ) pvPortMalloc( xSize + ipBUFFER_PADDING );\r
- configASSERT( pucEthernetBuffer );\r
-\r
- if( pucEthernetBuffer != NULL )\r
- {\r
- /* Enough space is left at the start of the buffer to place a pointer to\r
- the network buffer structure that references this Ethernet buffer.\r
- Return a pointer to the start of the Ethernet buffer itself. */\r
- pucEthernetBuffer += ipBUFFER_PADDING;\r
- }\r
-\r
- return pucEthernetBuffer;\r
-}\r
-/*-----------------------------------------------------------*/\r
-\r
-void vReleaseNetworkBuffer( uint8_t *pucEthernetBuffer )\r
-{\r
- /* There is space before the Ethernet buffer in which a pointer to the\r
- network buffer that references this Ethernet buffer is stored. Remove the\r
- space before freeing the buffer. */\r
- if( pucEthernetBuffer != NULL )\r
- {\r
- pucEthernetBuffer -= ipBUFFER_PADDING;\r
- vPortFree( ( void * ) pucEthernetBuffer );\r
- }\r
-}\r
-/*-----------------------------------------------------------*/\r
-\r
-NetworkBufferDescriptor_t *pxGetNetworkBufferWithDescriptor( size_t xRequestedSizeBytes, TickType_t xBlockTimeTicks )\r
-{\r
-NetworkBufferDescriptor_t *pxReturn = NULL;\r
-size_t uxCount;\r
-\r
- if( xNetworkBufferSemaphore != NULL )\r
- {\r
- if( ( xRequestedSizeBytes != 0u ) && ( xRequestedSizeBytes < ( size_t ) baMINIMAL_BUFFER_SIZE ) )\r
- {\r
- /* ARP packets can replace application packets, so the storage must be\r
- at least large enough to hold an ARP. */\r
- xRequestedSizeBytes = baMINIMAL_BUFFER_SIZE;\r
- }\r
-\r
- /* Add 2 bytes to xRequestedSizeBytes and round up xRequestedSizeBytes\r
- to the nearest multiple of N bytes, where N equals 'sizeof( size_t )'. */\r
- xRequestedSizeBytes += 2u;\r
- if( ( xRequestedSizeBytes & ( sizeof( size_t ) - 1u ) ) != 0u )\r
- {\r
- xRequestedSizeBytes = ( xRequestedSizeBytes | ( sizeof( size_t ) - 1u ) ) + 1u;\r
- }\r
-\r
- /* If there is a semaphore available, there is a network buffer available. */\r
- if( xSemaphoreTake( xNetworkBufferSemaphore, xBlockTimeTicks ) == pdPASS )\r
- {\r
- /* Protect the structure as it is accessed from tasks and interrupts. */\r
- taskENTER_CRITICAL();\r
- {\r
- pxReturn = ( NetworkBufferDescriptor_t * ) listGET_OWNER_OF_HEAD_ENTRY( &xFreeBuffersList );\r
- uxListRemove( &( pxReturn->xBufferListItem ) );\r
- }\r
- taskEXIT_CRITICAL();\r
-\r
- /* Reading UBaseType_t, no critical section needed. */\r
- uxCount = listCURRENT_LIST_LENGTH( &xFreeBuffersList );\r
-\r
- if( uxMinimumFreeNetworkBuffers > uxCount )\r
- {\r
- uxMinimumFreeNetworkBuffers = uxCount;\r
- }\r
-\r
- /* Allocate storage of exactly the requested size to the buffer. */\r
- configASSERT( pxReturn->pucEthernetBuffer == NULL );\r
- if( xRequestedSizeBytes > 0 )\r
- {\r
- /* Extra space is obtained so a pointer to the network buffer can\r
- be stored at the beginning of the buffer. */\r
- pxReturn->pucEthernetBuffer = ( uint8_t * ) pvPortMalloc( xRequestedSizeBytes + ipBUFFER_PADDING );\r
-\r
- if( pxReturn->pucEthernetBuffer == NULL )\r
- {\r
- /* The attempt to allocate storage for the buffer payload failed,\r
- so the network buffer structure cannot be used and must be\r
- released. */\r
- vReleaseNetworkBufferAndDescriptor( pxReturn );\r
- pxReturn = NULL;\r
- }\r
- else\r
- {\r
- /* Store a pointer to the network buffer structure in the\r
- buffer storage area, then move the buffer pointer on past the\r
- stored pointer so the pointer value is not overwritten by the\r
- application when the buffer is used. */\r
- *( ( NetworkBufferDescriptor_t ** ) ( pxReturn->pucEthernetBuffer ) ) = pxReturn;\r
- pxReturn->pucEthernetBuffer += ipBUFFER_PADDING;\r
-\r
- /* Store the actual size of the allocated buffer, which may be\r
- greater than the original requested size. */\r
- pxReturn->xDataLength = xRequestedSizeBytes;\r
-\r
- #if( ipconfigUSE_LINKED_RX_MESSAGES != 0 )\r
- {\r
- /* make sure the buffer is not linked */\r
- pxReturn->pxNextBuffer = NULL;\r
- }\r
- #endif /* ipconfigUSE_LINKED_RX_MESSAGES */\r
- }\r
- }\r
- else\r
- {\r
- /* A descriptor is being returned without an associated buffer being\r
- allocated. */\r
- }\r
- }\r
- }\r
-\r
- if( pxReturn == NULL )\r
- {\r
- iptraceFAILED_TO_OBTAIN_NETWORK_BUFFER();\r
- }\r
- else\r
- {\r
- iptraceNETWORK_BUFFER_OBTAINED( pxReturn );\r
- }\r
-\r
- return pxReturn;\r
-}\r
-/*-----------------------------------------------------------*/\r
-\r
-void vReleaseNetworkBufferAndDescriptor( NetworkBufferDescriptor_t * const pxNetworkBuffer )\r
-{\r
-BaseType_t xListItemAlreadyInFreeList;\r
-\r
- /* Ensure the buffer is returned to the list of free buffers before the\r
- counting semaphore is 'given' to say a buffer is available. Release the\r
- storage allocated to the buffer payload. THIS FILE SHOULD NOT BE USED\r
- IF THE PROJECT INCLUDES A MEMORY ALLOCATOR THAT WILL FRAGMENT THE HEAP\r
- MEMORY. For example, heap_2 must not be used, heap_4 can be used. */\r
- vReleaseNetworkBuffer( pxNetworkBuffer->pucEthernetBuffer );\r
- pxNetworkBuffer->pucEthernetBuffer = NULL;\r
-\r
- taskENTER_CRITICAL();\r
- {\r
- xListItemAlreadyInFreeList = listIS_CONTAINED_WITHIN( &xFreeBuffersList, &( pxNetworkBuffer->xBufferListItem ) );\r
-\r
- if( xListItemAlreadyInFreeList == pdFALSE )\r
- {\r
- vListInsertEnd( &xFreeBuffersList, &( pxNetworkBuffer->xBufferListItem ) );\r
- }\r
- }\r
- taskEXIT_CRITICAL();\r
-\r
- /*\r
- * Update the network state machine, unless the program fails to release its 'xNetworkBufferSemaphore'.\r
- * The program should only try to release its semaphore if 'xListItemAlreadyInFreeList' is false.\r
- */\r
- if( xListItemAlreadyInFreeList == pdFALSE )\r
- {\r
- if ( xSemaphoreGive( xNetworkBufferSemaphore ) == pdTRUE )\r
- {\r
- iptraceNETWORK_BUFFER_RELEASED( pxNetworkBuffer );\r
- }\r
- }\r
- else\r
- {\r
- iptraceNETWORK_BUFFER_RELEASED( pxNetworkBuffer );\r
- }\r
-}\r
-/*-----------------------------------------------------------*/\r
-\r
-/*\r
- * Returns the number of free network buffers\r
- */\r
-UBaseType_t uxGetNumberOfFreeNetworkBuffers( void )\r
-{\r
- return listCURRENT_LIST_LENGTH( &xFreeBuffersList );\r
-}\r
-/*-----------------------------------------------------------*/\r
-\r
-UBaseType_t uxGetMinimumFreeNetworkBuffers( void )\r
-{\r
- return uxMinimumFreeNetworkBuffers;\r
-}\r
-/*-----------------------------------------------------------*/\r
-\r
-NetworkBufferDescriptor_t *pxResizeNetworkBufferWithDescriptor( NetworkBufferDescriptor_t * pxNetworkBuffer, size_t xNewSizeBytes )\r
-{\r
-size_t xOriginalLength;\r
-uint8_t *pucBuffer;\r
-\r
- xOriginalLength = pxNetworkBuffer->xDataLength + ipBUFFER_PADDING;\r
- xNewSizeBytes = xNewSizeBytes + ipBUFFER_PADDING;\r
-\r
- pucBuffer = pucGetNetworkBuffer( &( xNewSizeBytes ) );\r
-\r
- if( pucBuffer == NULL )\r
- {\r
- /* In case the allocation fails, return NULL. */\r
- pxNetworkBuffer = NULL;\r
- }\r
- else\r
- {\r
- pxNetworkBuffer->xDataLength = xNewSizeBytes;\r
- if( xNewSizeBytes > xOriginalLength )\r
- {\r
- xNewSizeBytes = xOriginalLength;\r
- }\r
-\r
- memcpy( pucBuffer - ipBUFFER_PADDING, pxNetworkBuffer->pucEthernetBuffer - ipBUFFER_PADDING, xNewSizeBytes );\r
- vReleaseNetworkBuffer( pxNetworkBuffer->pucEthernetBuffer );\r
- pxNetworkBuffer->pucEthernetBuffer = pucBuffer;\r
- }\r
-\r
- return pxNetworkBuffer;\r
-}\r
-\r
+/*
+ * FreeRTOS+TCP V2.0.11
+ * Copyright (C) 2017 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * http://www.FreeRTOS.org
+ * http://aws.amazon.com/freertos
+ *
+ * 1 tab == 4 spaces!
+ */
+
+/******************************************************************************
+ *
+ * See the following web page for essential buffer allocation scheme usage and
+ * configuration details:
+ * http://www.FreeRTOS.org/FreeRTOS-Plus/FreeRTOS_Plus_TCP/Embedded_Ethernet_Buffer_Management.html
+ *
+ ******************************************************************************/
+
+/* THIS FILE SHOULD NOT BE USED IF THE PROJECT INCLUDES A MEMORY ALLOCATOR
+THAT WILL FRAGMENT THE HEAP MEMORY. For example, heap_2 must not be used,
+heap_4 can be used. */
+
+
+/* Standard includes. */
+#include <stdint.h>
+
+/* FreeRTOS includes. */
+#include "FreeRTOS.h"
+#include "task.h"
+#include "semphr.h"
+
+/* FreeRTOS+TCP includes. */
+#include "FreeRTOS_IP.h"
+#include "FreeRTOS_UDP_IP.h"
+#include "FreeRTOS_IP_Private.h"
+#include "NetworkInterface.h"
+#include "NetworkBufferManagement.h"
+
+/* The obtained network buffer must be large enough to hold a packet that might
+replace the packet that was requested to be sent. */
+#if ipconfigUSE_TCP == 1
+ #define baMINIMAL_BUFFER_SIZE sizeof( TCPPacket_t )
+#else
+ #define baMINIMAL_BUFFER_SIZE sizeof( ARPPacket_t )
+#endif /* ipconfigUSE_TCP == 1 */
+
+/*_RB_ This is too complex not to have an explanation. */
+#if defined( ipconfigETHERNET_MINIMUM_PACKET_BYTES )
+ #define ASSERT_CONCAT_(a, b) a##b
+ #define ASSERT_CONCAT(a, b) ASSERT_CONCAT_(a, b)
+ #define STATIC_ASSERT(e) \
+ ;enum { ASSERT_CONCAT(assert_line_, __LINE__) = 1/(!!(e)) }
+
+ STATIC_ASSERT( ipconfigETHERNET_MINIMUM_PACKET_BYTES <= baMINIMAL_BUFFER_SIZE );
+#endif
+
+/* A list of free (available) NetworkBufferDescriptor_t structures. */
+static List_t xFreeBuffersList;
+
+/* Some statistics about the use of buffers. */
+static size_t uxMinimumFreeNetworkBuffers;
+
+/* Declares the pool of NetworkBufferDescriptor_t structures that are available
+to the system. All the network buffers referenced from xFreeBuffersList exist
+in this array. The array is not accessed directly except during initialisation,
+when the xFreeBuffersList is filled (as all the buffers are free when the system
+is booted). */
+static NetworkBufferDescriptor_t xNetworkBufferDescriptors[ ipconfigNUM_NETWORK_BUFFER_DESCRIPTORS ];
+
+/* This constant is defined as false to let FreeRTOS_TCP_IP.c know that the
+network buffers have a variable size: resizing may be necessary */
+const BaseType_t xBufferAllocFixedSize = pdFALSE;
+
+/* The semaphore used to obtain network buffers. */
+static SemaphoreHandle_t xNetworkBufferSemaphore = NULL;
+
+/*-----------------------------------------------------------*/
+
+BaseType_t xNetworkBuffersInitialise( void )
+{
+BaseType_t xReturn, x;
+
+ /* Only initialise the buffers and their associated kernel objects if they
+ have not been initialised before. */
+ if( xNetworkBufferSemaphore == NULL )
+ {
+ xNetworkBufferSemaphore = xSemaphoreCreateCounting( ipconfigNUM_NETWORK_BUFFER_DESCRIPTORS, ipconfigNUM_NETWORK_BUFFER_DESCRIPTORS );
+ configASSERT( xNetworkBufferSemaphore );
+
+ if( xNetworkBufferSemaphore != NULL )
+ {
+ #if ( configQUEUE_REGISTRY_SIZE > 0 )
+ {
+ vQueueAddToRegistry( xNetworkBufferSemaphore, "NetBufSem" );
+ }
+ #endif /* configQUEUE_REGISTRY_SIZE */
+
+ /* If the trace recorder code is included name the semaphore for viewing
+ in FreeRTOS+Trace. */
+ #if( ipconfigINCLUDE_EXAMPLE_FREERTOS_PLUS_TRACE_CALLS == 1 )
+ {
+ extern QueueHandle_t xNetworkEventQueue;
+ vTraceSetQueueName( xNetworkEventQueue, "IPStackEvent" );
+ vTraceSetQueueName( xNetworkBufferSemaphore, "NetworkBufferCount" );
+ }
+ #endif /* ipconfigINCLUDE_EXAMPLE_FREERTOS_PLUS_TRACE_CALLS == 1 */
+
+ vListInitialise( &xFreeBuffersList );
+
+ /* Initialise all the network buffers. No storage is allocated to
+ the buffers yet. */
+ for( x = 0; x < ipconfigNUM_NETWORK_BUFFER_DESCRIPTORS; x++ )
+ {
+ /* Initialise and set the owner of the buffer list items. */
+ xNetworkBufferDescriptors[ x ].pucEthernetBuffer = NULL;
+ vListInitialiseItem( &( xNetworkBufferDescriptors[ x ].xBufferListItem ) );
+ listSET_LIST_ITEM_OWNER( &( xNetworkBufferDescriptors[ x ].xBufferListItem ), &xNetworkBufferDescriptors[ x ] );
+
+ /* Currently, all buffers are available for use. */
+ vListInsert( &xFreeBuffersList, &( xNetworkBufferDescriptors[ x ].xBufferListItem ) );
+ }
+
+ uxMinimumFreeNetworkBuffers = ipconfigNUM_NETWORK_BUFFER_DESCRIPTORS;
+ }
+ }
+
+ if( xNetworkBufferSemaphore == NULL )
+ {
+ xReturn = pdFAIL;
+ }
+ else
+ {
+ xReturn = pdPASS;
+ }
+
+ return xReturn;
+}
+/*-----------------------------------------------------------*/
+
+uint8_t *pucGetNetworkBuffer( size_t *pxRequestedSizeBytes )
+{
+uint8_t *pucEthernetBuffer;
+size_t xSize = *pxRequestedSizeBytes;
+
+ if( xSize < baMINIMAL_BUFFER_SIZE )
+ {
+ /* Buffers must be at least large enough to hold a TCP-packet with
+ headers, or an ARP packet, in case TCP is not included. */
+ xSize = baMINIMAL_BUFFER_SIZE;
+ }
+
+ /* Round up xSize to the nearest multiple of N bytes,
+ where N equals 'sizeof( size_t )'. */
+ if( ( xSize & ( sizeof( size_t ) - 1u ) ) != 0u )
+ {
+ xSize = ( xSize | ( sizeof( size_t ) - 1u ) ) + 1u;
+ }
+ *pxRequestedSizeBytes = xSize;
+
+ /* Allocate a buffer large enough to store the requested Ethernet frame size
+ and a pointer to a network buffer structure (hence the addition of
+ ipBUFFER_PADDING bytes). */
+ pucEthernetBuffer = ( uint8_t * ) pvPortMalloc( xSize + ipBUFFER_PADDING );
+ configASSERT( pucEthernetBuffer );
+
+ if( pucEthernetBuffer != NULL )
+ {
+ /* Enough space is left at the start of the buffer to place a pointer to
+ the network buffer structure that references this Ethernet buffer.
+ Return a pointer to the start of the Ethernet buffer itself. */
+ pucEthernetBuffer += ipBUFFER_PADDING;
+ }
+
+ return pucEthernetBuffer;
+}
+/*-----------------------------------------------------------*/
+
+void vReleaseNetworkBuffer( uint8_t *pucEthernetBuffer )
+{
+ /* There is space before the Ethernet buffer in which a pointer to the
+ network buffer that references this Ethernet buffer is stored. Remove the
+ space before freeing the buffer. */
+ if( pucEthernetBuffer != NULL )
+ {
+ pucEthernetBuffer -= ipBUFFER_PADDING;
+ vPortFree( ( void * ) pucEthernetBuffer );
+ }
+}
+/*-----------------------------------------------------------*/
+
+NetworkBufferDescriptor_t *pxGetNetworkBufferWithDescriptor( size_t xRequestedSizeBytes, TickType_t xBlockTimeTicks )
+{
+NetworkBufferDescriptor_t *pxReturn = NULL;
+size_t uxCount;
+
+ if( xNetworkBufferSemaphore != NULL )
+ {
+ if( ( xRequestedSizeBytes != 0u ) && ( xRequestedSizeBytes < ( size_t ) baMINIMAL_BUFFER_SIZE ) )
+ {
+ /* ARP packets can replace application packets, so the storage must be
+ at least large enough to hold an ARP. */
+ xRequestedSizeBytes = baMINIMAL_BUFFER_SIZE;
+ }
+
+ /* Add 2 bytes to xRequestedSizeBytes and round up xRequestedSizeBytes
+ to the nearest multiple of N bytes, where N equals 'sizeof( size_t )'. */
+ xRequestedSizeBytes += 2u;
+ if( ( xRequestedSizeBytes & ( sizeof( size_t ) - 1u ) ) != 0u )
+ {
+ xRequestedSizeBytes = ( xRequestedSizeBytes | ( sizeof( size_t ) - 1u ) ) + 1u;
+ }
+
+ /* If there is a semaphore available, there is a network buffer available. */
+ if( xSemaphoreTake( xNetworkBufferSemaphore, xBlockTimeTicks ) == pdPASS )
+ {
+ /* Protect the structure as it is accessed from tasks and interrupts. */
+ taskENTER_CRITICAL();
+ {
+ pxReturn = ( NetworkBufferDescriptor_t * ) listGET_OWNER_OF_HEAD_ENTRY( &xFreeBuffersList );
+ uxListRemove( &( pxReturn->xBufferListItem ) );
+ }
+ taskEXIT_CRITICAL();
+
+ /* Reading UBaseType_t, no critical section needed. */
+ uxCount = listCURRENT_LIST_LENGTH( &xFreeBuffersList );
+
+ if( uxMinimumFreeNetworkBuffers > uxCount )
+ {
+ uxMinimumFreeNetworkBuffers = uxCount;
+ }
+
+ /* Allocate storage of exactly the requested size to the buffer. */
+ configASSERT( pxReturn->pucEthernetBuffer == NULL );
+ if( xRequestedSizeBytes > 0 )
+ {
+ /* Extra space is obtained so a pointer to the network buffer can
+ be stored at the beginning of the buffer. */
+ pxReturn->pucEthernetBuffer = ( uint8_t * ) pvPortMalloc( xRequestedSizeBytes + ipBUFFER_PADDING );
+
+ if( pxReturn->pucEthernetBuffer == NULL )
+ {
+ /* The attempt to allocate storage for the buffer payload failed,
+ so the network buffer structure cannot be used and must be
+ released. */
+ vReleaseNetworkBufferAndDescriptor( pxReturn );
+ pxReturn = NULL;
+ }
+ else
+ {
+ /* Store a pointer to the network buffer structure in the
+ buffer storage area, then move the buffer pointer on past the
+ stored pointer so the pointer value is not overwritten by the
+ application when the buffer is used. */
+ *( ( NetworkBufferDescriptor_t ** ) ( pxReturn->pucEthernetBuffer ) ) = pxReturn;
+ pxReturn->pucEthernetBuffer += ipBUFFER_PADDING;
+
+ /* Store the actual size of the allocated buffer, which may be
+ greater than the original requested size. */
+ pxReturn->xDataLength = xRequestedSizeBytes;
+
+ #if( ipconfigUSE_LINKED_RX_MESSAGES != 0 )
+ {
+ /* make sure the buffer is not linked */
+ pxReturn->pxNextBuffer = NULL;
+ }
+ #endif /* ipconfigUSE_LINKED_RX_MESSAGES */
+ }
+ }
+ else
+ {
+ /* A descriptor is being returned without an associated buffer being
+ allocated. */
+ }
+ }
+ }
+
+ if( pxReturn == NULL )
+ {
+ iptraceFAILED_TO_OBTAIN_NETWORK_BUFFER();
+ }
+ else
+ {
+ iptraceNETWORK_BUFFER_OBTAINED( pxReturn );
+ }
+
+ return pxReturn;
+}
+/*-----------------------------------------------------------*/
+
+void vReleaseNetworkBufferAndDescriptor( NetworkBufferDescriptor_t * const pxNetworkBuffer )
+{
+BaseType_t xListItemAlreadyInFreeList;
+
+ /* Ensure the buffer is returned to the list of free buffers before the
+ counting semaphore is 'given' to say a buffer is available. Release the
+ storage allocated to the buffer payload. THIS FILE SHOULD NOT BE USED
+ IF THE PROJECT INCLUDES A MEMORY ALLOCATOR THAT WILL FRAGMENT THE HEAP
+ MEMORY. For example, heap_2 must not be used, heap_4 can be used. */
+ vReleaseNetworkBuffer( pxNetworkBuffer->pucEthernetBuffer );
+ pxNetworkBuffer->pucEthernetBuffer = NULL;
+
+ taskENTER_CRITICAL();
+ {
+ xListItemAlreadyInFreeList = listIS_CONTAINED_WITHIN( &xFreeBuffersList, &( pxNetworkBuffer->xBufferListItem ) );
+
+ if( xListItemAlreadyInFreeList == pdFALSE )
+ {
+ vListInsertEnd( &xFreeBuffersList, &( pxNetworkBuffer->xBufferListItem ) );
+ }
+ }
+ taskEXIT_CRITICAL();
+
+ /*
+ * Update the network state machine, unless the program fails to release its 'xNetworkBufferSemaphore'.
+ * The program should only try to release its semaphore if 'xListItemAlreadyInFreeList' is false.
+ */
+ if( xListItemAlreadyInFreeList == pdFALSE )
+ {
+ if ( xSemaphoreGive( xNetworkBufferSemaphore ) == pdTRUE )
+ {
+ iptraceNETWORK_BUFFER_RELEASED( pxNetworkBuffer );
+ }
+ }
+ else
+ {
+ iptraceNETWORK_BUFFER_RELEASED( pxNetworkBuffer );
+ }
+}
+/*-----------------------------------------------------------*/
+
+/*
+ * Returns the number of free network buffers
+ */
+UBaseType_t uxGetNumberOfFreeNetworkBuffers( void )
+{
+ return listCURRENT_LIST_LENGTH( &xFreeBuffersList );
+}
+/*-----------------------------------------------------------*/
+
+UBaseType_t uxGetMinimumFreeNetworkBuffers( void )
+{
+ return uxMinimumFreeNetworkBuffers;
+}
+/*-----------------------------------------------------------*/
+
+NetworkBufferDescriptor_t *pxResizeNetworkBufferWithDescriptor( NetworkBufferDescriptor_t * pxNetworkBuffer, size_t xNewSizeBytes )
+{
+size_t xOriginalLength;
+uint8_t *pucBuffer;
+
+ xOriginalLength = pxNetworkBuffer->xDataLength + ipBUFFER_PADDING;
+ xNewSizeBytes = xNewSizeBytes + ipBUFFER_PADDING;
+
+ pucBuffer = pucGetNetworkBuffer( &( xNewSizeBytes ) );
+
+ if( pucBuffer == NULL )
+ {
+ /* In case the allocation fails, return NULL. */
+ pxNetworkBuffer = NULL;
+ }
+ else
+ {
+ pxNetworkBuffer->xDataLength = xNewSizeBytes;
+ if( xNewSizeBytes > xOriginalLength )
+ {
+ xNewSizeBytes = xOriginalLength;
+ }
+
+ memcpy( pucBuffer - ipBUFFER_PADDING, pxNetworkBuffer->pucEthernetBuffer - ipBUFFER_PADDING, xNewSizeBytes );
+ vReleaseNetworkBuffer( pxNetworkBuffer->pucEthernetBuffer );
+ pxNetworkBuffer->pucEthernetBuffer = pucBuffer;
+ }
+
+ return pxNetworkBuffer;
+}
+