1 files changed, 393 insertions, 393 deletions
diff --git a/FreeRTOS-Plus/Source/FreeRTOS-Plus-TCP/portable/BufferManagement/BufferAllocation_2.c b/FreeRTOS-Plus/Source/FreeRTOS-Plus-TCP/portable/BufferManagement/BufferAllocation_2.c
index e008da07a..51f5410a4 100644
--- a/FreeRTOS-Plus/Source/FreeRTOS-Plus-TCP/portable/BufferManagement/BufferAllocation_2.c
+++ b/FreeRTOS-Plus/Source/FreeRTOS-Plus-TCP/portable/BufferManagement/BufferAllocation_2.c
@@ -1,393 +1,393 @@
-/*
- * 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;
-}
-
+/*
+ * 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;
+}
+