diff options
Diffstat (limited to 'freertos/src/portable/MemMang/heap_4.c')
-rw-r--r-- | freertos/src/portable/MemMang/heap_4.c | 914 |
1 files changed, 436 insertions, 478 deletions
diff --git a/freertos/src/portable/MemMang/heap_4.c b/freertos/src/portable/MemMang/heap_4.c index e7c7ade..bbd7bd8 100644 --- a/freertos/src/portable/MemMang/heap_4.c +++ b/freertos/src/portable/MemMang/heap_4.c @@ -1,478 +1,436 @@ -/* - FreeRTOS V9.0.0 - Copyright (C) 2016 Real Time Engineers Ltd. - All rights reserved - - VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION. - - 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 on the following - link: http://www.freertos.org/a00114.html - - *************************************************************************** - * * - * FreeRTOS provides completely free yet professionally developed, * - * robust, strictly quality controlled, supported, and cross * - * platform software that is more than just the market leader, it * - * is the industry's de facto standard. * - * * - * Help yourself get started quickly while simultaneously helping * - * to support the FreeRTOS project by purchasing a FreeRTOS * - * tutorial book, reference manual, or both: * - * http://www.FreeRTOS.org/Documentation * - * * - *************************************************************************** - - http://www.FreeRTOS.org/FAQHelp.html - Having a problem? Start by reading - the FAQ page "My application does not run, what could be wrong?". Have you - defined configASSERT()? - - http://www.FreeRTOS.org/support - In return for receiving this top quality - embedded software for free we request you assist our global community by - participating in the support forum. - - http://www.FreeRTOS.org/training - Investing in training allows your team to - be as productive as possible as early as possible. Now you can receive - FreeRTOS training directly from Richard Barry, CEO of Real Time Engineers - Ltd, and the world's leading authority on the world's leading RTOS. - - 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.FreeRTOS.org/labs - Where new FreeRTOS products go to incubate. - Come and try FreeRTOS+TCP, our new open source TCP/IP stack for FreeRTOS. - - http://www.OpenRTOS.com - Real Time Engineers ltd. license FreeRTOS to High - Integrity Systems ltd. to sell under the OpenRTOS brand. Low cost OpenRTOS - licenses offer ticketed support, indemnification and commercial 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! -*/ - -/* - * A sample implementation of pvPortMalloc() and vPortFree() that combines - * (coalescences) adjacent memory blocks as they are freed, and in so doing - * limits memory fragmentation. - * - * See heap_1.c, heap_2.c and heap_3.c for alternative implementations, and the - * memory management pages of http://www.FreeRTOS.org for more information. - */ -#include <stdlib.h> - -/* Defining MPU_WRAPPERS_INCLUDED_FROM_API_FILE prevents task.h from redefining -all the API functions to use the MPU wrappers. That should only be done when -task.h is included from an application file. */ -#define MPU_WRAPPERS_INCLUDED_FROM_API_FILE - -#include "FreeRTOS.h" -#include "task.h" - -#undef MPU_WRAPPERS_INCLUDED_FROM_API_FILE - -#if( configSUPPORT_DYNAMIC_ALLOCATION == 0 ) - #error This file must not be used if configSUPPORT_DYNAMIC_ALLOCATION is 0 -#endif - -/* Block sizes must not get too small. */ -#define heapMINIMUM_BLOCK_SIZE ( ( size_t ) ( xHeapStructSize << 1 ) ) - -/* Assumes 8bit bytes! */ -#define heapBITS_PER_BYTE ( ( size_t ) 8 ) - -/* Allocate the memory for the heap. */ -#if( configAPPLICATION_ALLOCATED_HEAP == 1 ) - /* The application writer has already defined the array used for the RTOS - heap - probably so it can be placed in a special segment or address. */ - extern uint8_t ucHeap[ configTOTAL_HEAP_SIZE ]; -#else - static uint8_t ucHeap[ configTOTAL_HEAP_SIZE ]; -#endif /* configAPPLICATION_ALLOCATED_HEAP */ - -/* Define the linked list structure. This is used to link free blocks in order -of their memory address. */ -typedef struct A_BLOCK_LINK -{ - struct A_BLOCK_LINK *pxNextFreeBlock; /*<< The next free block in the list. */ - size_t xBlockSize; /*<< The size of the free block. */ -} BlockLink_t; - -/*-----------------------------------------------------------*/ - -/* - * Inserts a block of memory that is being freed into the correct position in - * the list of free memory blocks. The block being freed will be merged with - * the block in front it and/or the block behind it if the memory blocks are - * adjacent to each other. - */ -static void prvInsertBlockIntoFreeList( BlockLink_t *pxBlockToInsert ); - -/* - * Called automatically to setup the required heap structures the first time - * pvPortMalloc() is called. - */ -static void prvHeapInit( void ); - -/*-----------------------------------------------------------*/ - -/* The size of the structure placed at the beginning of each allocated memory -block must by correctly byte aligned. */ -static const size_t xHeapStructSize = ( sizeof( BlockLink_t ) + ( ( size_t ) ( portBYTE_ALIGNMENT - 1 ) ) ) & ~( ( size_t ) portBYTE_ALIGNMENT_MASK ); - -/* Create a couple of list links to mark the start and end of the list. */ -static BlockLink_t xStart, *pxEnd = NULL; - -/* Keeps track of the number of free bytes remaining, but says nothing about -fragmentation. */ -static size_t xFreeBytesRemaining = 0U; -static size_t xMinimumEverFreeBytesRemaining = 0U; - -/* Gets set to the top bit of an size_t type. When this bit in the xBlockSize -member of an BlockLink_t structure is set then the block belongs to the -application. When the bit is free the block is still part of the free heap -space. */ -static size_t xBlockAllocatedBit = 0; - -/*-----------------------------------------------------------*/ - -void *pvPortMalloc( size_t xWantedSize ) -{ -BlockLink_t *pxBlock, *pxPreviousBlock, *pxNewBlockLink; -void *pvReturn = NULL; - - vTaskSuspendAll(); - { - /* If this is the first call to malloc then the heap will require - initialisation to setup the list of free blocks. */ - if( pxEnd == NULL ) - { - prvHeapInit(); - } - else - { - mtCOVERAGE_TEST_MARKER(); - } - - /* Check the requested block size is not so large that the top bit is - set. The top bit of the block size member of the BlockLink_t structure - is used to determine who owns the block - the application or the - kernel, so it must be free. */ - if( ( xWantedSize & xBlockAllocatedBit ) == 0 ) - { - /* The wanted size is increased so it can contain a BlockLink_t - structure in addition to the requested amount of bytes. */ - if( xWantedSize > 0 ) - { - xWantedSize += xHeapStructSize; - - /* Ensure that blocks are always aligned to the required number - of bytes. */ - if( ( xWantedSize & portBYTE_ALIGNMENT_MASK ) != 0x00 ) - { - /* Byte alignment required. */ - xWantedSize += ( portBYTE_ALIGNMENT - ( xWantedSize & portBYTE_ALIGNMENT_MASK ) ); - configASSERT( ( xWantedSize & portBYTE_ALIGNMENT_MASK ) == 0 ); - } - else - { - mtCOVERAGE_TEST_MARKER(); - } - } - else - { - mtCOVERAGE_TEST_MARKER(); - } - - if( ( xWantedSize > 0 ) && ( xWantedSize <= xFreeBytesRemaining ) ) - { - /* Traverse the list from the start (lowest address) block until - one of adequate size is found. */ - pxPreviousBlock = &xStart; - pxBlock = xStart.pxNextFreeBlock; - while( ( pxBlock->xBlockSize < xWantedSize ) && ( pxBlock->pxNextFreeBlock != NULL ) ) - { - pxPreviousBlock = pxBlock; - pxBlock = pxBlock->pxNextFreeBlock; - } - - /* If the end marker was reached then a block of adequate size - was not found. */ - if( pxBlock != pxEnd ) - { - /* Return the memory space pointed to - jumping over the - BlockLink_t structure at its start. */ - pvReturn = ( void * ) ( ( ( uint8_t * ) pxPreviousBlock->pxNextFreeBlock ) + xHeapStructSize ); - - /* This block is being returned for use so must be taken out - of the list of free blocks. */ - pxPreviousBlock->pxNextFreeBlock = pxBlock->pxNextFreeBlock; - - /* If the block is larger than required it can be split into - two. */ - if( ( pxBlock->xBlockSize - xWantedSize ) > heapMINIMUM_BLOCK_SIZE ) - { - /* This block is to be split into two. Create a new - block following the number of bytes requested. The void - cast is used to prevent byte alignment warnings from the - compiler. */ - pxNewBlockLink = ( void * ) ( ( ( uint8_t * ) pxBlock ) + xWantedSize ); - configASSERT( ( ( ( size_t ) pxNewBlockLink ) & portBYTE_ALIGNMENT_MASK ) == 0 ); - - /* Calculate the sizes of two blocks split from the - single block. */ - pxNewBlockLink->xBlockSize = pxBlock->xBlockSize - xWantedSize; - pxBlock->xBlockSize = xWantedSize; - - /* Insert the new block into the list of free blocks. */ - prvInsertBlockIntoFreeList( pxNewBlockLink ); - } - else - { - mtCOVERAGE_TEST_MARKER(); - } - - xFreeBytesRemaining -= pxBlock->xBlockSize; - - if( xFreeBytesRemaining < xMinimumEverFreeBytesRemaining ) - { - xMinimumEverFreeBytesRemaining = xFreeBytesRemaining; - } - else - { - mtCOVERAGE_TEST_MARKER(); - } - - /* The block is being returned - it is allocated and owned - by the application and has no "next" block. */ - pxBlock->xBlockSize |= xBlockAllocatedBit; - pxBlock->pxNextFreeBlock = NULL; - } - else - { - mtCOVERAGE_TEST_MARKER(); - } - } - else - { - mtCOVERAGE_TEST_MARKER(); - } - } - else - { - mtCOVERAGE_TEST_MARKER(); - } - - traceMALLOC( pvReturn, xWantedSize ); - } - ( void ) xTaskResumeAll(); - - #if( configUSE_MALLOC_FAILED_HOOK == 1 ) - { - if( pvReturn == NULL ) - { - extern void vApplicationMallocFailedHook( void ); - vApplicationMallocFailedHook(); - } - else - { - mtCOVERAGE_TEST_MARKER(); - } - } - #endif - - configASSERT( ( ( ( size_t ) pvReturn ) & ( size_t ) portBYTE_ALIGNMENT_MASK ) == 0 ); - return pvReturn; -} -/*-----------------------------------------------------------*/ - -void vPortFree( void *pv ) -{ -uint8_t *puc = ( uint8_t * ) pv; -BlockLink_t *pxLink; - - if( pv != NULL ) - { - /* The memory being freed will have an BlockLink_t structure immediately - before it. */ - puc -= xHeapStructSize; - - /* This casting is to keep the compiler from issuing warnings. */ - pxLink = ( void * ) puc; - - /* Check the block is actually allocated. */ - configASSERT( ( pxLink->xBlockSize & xBlockAllocatedBit ) != 0 ); - configASSERT( pxLink->pxNextFreeBlock == NULL ); - - if( ( pxLink->xBlockSize & xBlockAllocatedBit ) != 0 ) - { - if( pxLink->pxNextFreeBlock == NULL ) - { - /* The block is being returned to the heap - it is no longer - allocated. */ - pxLink->xBlockSize &= ~xBlockAllocatedBit; - - vTaskSuspendAll(); - { - /* Add this block to the list of free blocks. */ - xFreeBytesRemaining += pxLink->xBlockSize; - traceFREE( pv, pxLink->xBlockSize ); - prvInsertBlockIntoFreeList( ( ( BlockLink_t * ) pxLink ) ); - } - ( void ) xTaskResumeAll(); - } - else - { - mtCOVERAGE_TEST_MARKER(); - } - } - else - { - mtCOVERAGE_TEST_MARKER(); - } - } -} -/*-----------------------------------------------------------*/ - -size_t xPortGetFreeHeapSize( void ) -{ - return xFreeBytesRemaining; -} -/*-----------------------------------------------------------*/ - -size_t xPortGetMinimumEverFreeHeapSize( void ) -{ - return xMinimumEverFreeBytesRemaining; -} -/*-----------------------------------------------------------*/ - -void vPortInitialiseBlocks( void ) -{ - /* This just exists to keep the linker quiet. */ -} -/*-----------------------------------------------------------*/ - -static void prvHeapInit( void ) -{ -BlockLink_t *pxFirstFreeBlock; -uint8_t *pucAlignedHeap; -size_t uxAddress; -size_t xTotalHeapSize = configTOTAL_HEAP_SIZE; - - /* Ensure the heap starts on a correctly aligned boundary. */ - uxAddress = ( size_t ) ucHeap; - - if( ( uxAddress & portBYTE_ALIGNMENT_MASK ) != 0 ) - { - uxAddress += ( portBYTE_ALIGNMENT - 1 ); - uxAddress &= ~( ( size_t ) portBYTE_ALIGNMENT_MASK ); - xTotalHeapSize -= uxAddress - ( size_t ) ucHeap; - } - - pucAlignedHeap = ( uint8_t * ) uxAddress; - - /* xStart is used to hold a pointer to the first item in the list of free - blocks. The void cast is used to prevent compiler warnings. */ - xStart.pxNextFreeBlock = ( void * ) pucAlignedHeap; - xStart.xBlockSize = ( size_t ) 0; - - /* pxEnd is used to mark the end of the list of free blocks and is inserted - at the end of the heap space. */ - uxAddress = ( ( size_t ) pucAlignedHeap ) + xTotalHeapSize; - uxAddress -= xHeapStructSize; - uxAddress &= ~( ( size_t ) portBYTE_ALIGNMENT_MASK ); - pxEnd = ( void * ) uxAddress; - pxEnd->xBlockSize = 0; - pxEnd->pxNextFreeBlock = NULL; - - /* To start with there is a single free block that is sized to take up the - entire heap space, minus the space taken by pxEnd. */ - pxFirstFreeBlock = ( void * ) pucAlignedHeap; - pxFirstFreeBlock->xBlockSize = uxAddress - ( size_t ) pxFirstFreeBlock; - pxFirstFreeBlock->pxNextFreeBlock = pxEnd; - - /* Only one block exists - and it covers the entire usable heap space. */ - xMinimumEverFreeBytesRemaining = pxFirstFreeBlock->xBlockSize; - xFreeBytesRemaining = pxFirstFreeBlock->xBlockSize; - - /* Work out the position of the top bit in a size_t variable. */ - xBlockAllocatedBit = ( ( size_t ) 1 ) << ( ( sizeof( size_t ) * heapBITS_PER_BYTE ) - 1 ); -} -/*-----------------------------------------------------------*/ - -static void prvInsertBlockIntoFreeList( BlockLink_t *pxBlockToInsert ) -{ -BlockLink_t *pxIterator; -uint8_t *puc; - - /* Iterate through the list until a block is found that has a higher address - than the block being inserted. */ - for( pxIterator = &xStart; pxIterator->pxNextFreeBlock < pxBlockToInsert; pxIterator = pxIterator->pxNextFreeBlock ) - { - /* Nothing to do here, just iterate to the right position. */ - } - - /* Do the block being inserted, and the block it is being inserted after - make a contiguous block of memory? */ - puc = ( uint8_t * ) pxIterator; - if( ( puc + pxIterator->xBlockSize ) == ( uint8_t * ) pxBlockToInsert ) - { - pxIterator->xBlockSize += pxBlockToInsert->xBlockSize; - pxBlockToInsert = pxIterator; - } - else - { - mtCOVERAGE_TEST_MARKER(); - } - - /* Do the block being inserted, and the block it is being inserted before - make a contiguous block of memory? */ - puc = ( uint8_t * ) pxBlockToInsert; - if( ( puc + pxBlockToInsert->xBlockSize ) == ( uint8_t * ) pxIterator->pxNextFreeBlock ) - { - if( pxIterator->pxNextFreeBlock != pxEnd ) - { - /* Form one big block from the two blocks. */ - pxBlockToInsert->xBlockSize += pxIterator->pxNextFreeBlock->xBlockSize; - pxBlockToInsert->pxNextFreeBlock = pxIterator->pxNextFreeBlock->pxNextFreeBlock; - } - else - { - pxBlockToInsert->pxNextFreeBlock = pxEnd; - } - } - else - { - pxBlockToInsert->pxNextFreeBlock = pxIterator->pxNextFreeBlock; - } - - /* If the block being inserted plugged a gab, so was merged with the block - before and the block after, then it's pxNextFreeBlock pointer will have - already been set, and should not be set here as that would make it point - to itself. */ - if( pxIterator != pxBlockToInsert ) - { - pxIterator->pxNextFreeBlock = pxBlockToInsert; - } - else - { - mtCOVERAGE_TEST_MARKER(); - } -} - +/*
+ * FreeRTOS Kernel V10.1.1
+ * Copyright (C) 2018 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!
+ */
+
+/*
+ * A sample implementation of pvPortMalloc() and vPortFree() that combines
+ * (coalescences) adjacent memory blocks as they are freed, and in so doing
+ * limits memory fragmentation.
+ *
+ * See heap_1.c, heap_2.c and heap_3.c for alternative implementations, and the
+ * memory management pages of http://www.FreeRTOS.org for more information.
+ */
+#include <stdlib.h>
+
+/* Defining MPU_WRAPPERS_INCLUDED_FROM_API_FILE prevents task.h from redefining
+all the API functions to use the MPU wrappers. That should only be done when
+task.h is included from an application file. */
+#define MPU_WRAPPERS_INCLUDED_FROM_API_FILE
+
+#include "FreeRTOS.h"
+#include "task.h"
+
+#undef MPU_WRAPPERS_INCLUDED_FROM_API_FILE
+
+#if( configSUPPORT_DYNAMIC_ALLOCATION == 0 )
+ #error This file must not be used if configSUPPORT_DYNAMIC_ALLOCATION is 0
+#endif
+
+/* Block sizes must not get too small. */
+#define heapMINIMUM_BLOCK_SIZE ( ( size_t ) ( xHeapStructSize << 1 ) )
+
+/* Assumes 8bit bytes! */
+#define heapBITS_PER_BYTE ( ( size_t ) 8 )
+
+/* Allocate the memory for the heap. */
+#if( configAPPLICATION_ALLOCATED_HEAP == 1 )
+ /* The application writer has already defined the array used for the RTOS
+ heap - probably so it can be placed in a special segment or address. */
+ extern uint8_t ucHeap[ configTOTAL_HEAP_SIZE ];
+#else
+ static uint8_t ucHeap[ configTOTAL_HEAP_SIZE ];
+#endif /* configAPPLICATION_ALLOCATED_HEAP */
+
+/* Define the linked list structure. This is used to link free blocks in order
+of their memory address. */
+typedef struct A_BLOCK_LINK
+{
+ struct A_BLOCK_LINK *pxNextFreeBlock; /*<< The next free block in the list. */
+ size_t xBlockSize; /*<< The size of the free block. */
+} BlockLink_t;
+
+/*-----------------------------------------------------------*/
+
+/*
+ * Inserts a block of memory that is being freed into the correct position in
+ * the list of free memory blocks. The block being freed will be merged with
+ * the block in front it and/or the block behind it if the memory blocks are
+ * adjacent to each other.
+ */
+static void prvInsertBlockIntoFreeList( BlockLink_t *pxBlockToInsert );
+
+/*
+ * Called automatically to setup the required heap structures the first time
+ * pvPortMalloc() is called.
+ */
+static void prvHeapInit( void );
+
+/*-----------------------------------------------------------*/
+
+/* The size of the structure placed at the beginning of each allocated memory
+block must by correctly byte aligned. */
+static const size_t xHeapStructSize = ( sizeof( BlockLink_t ) + ( ( size_t ) ( portBYTE_ALIGNMENT - 1 ) ) ) & ~( ( size_t ) portBYTE_ALIGNMENT_MASK );
+
+/* Create a couple of list links to mark the start and end of the list. */
+static BlockLink_t xStart, *pxEnd = NULL;
+
+/* Keeps track of the number of free bytes remaining, but says nothing about
+fragmentation. */
+static size_t xFreeBytesRemaining = 0U;
+static size_t xMinimumEverFreeBytesRemaining = 0U;
+
+/* Gets set to the top bit of an size_t type. When this bit in the xBlockSize
+member of an BlockLink_t structure is set then the block belongs to the
+application. When the bit is free the block is still part of the free heap
+space. */
+static size_t xBlockAllocatedBit = 0;
+
+/*-----------------------------------------------------------*/
+
+void *pvPortMalloc( size_t xWantedSize )
+{
+BlockLink_t *pxBlock, *pxPreviousBlock, *pxNewBlockLink;
+void *pvReturn = NULL;
+
+ vTaskSuspendAll();
+ {
+ /* If this is the first call to malloc then the heap will require
+ initialisation to setup the list of free blocks. */
+ if( pxEnd == NULL )
+ {
+ prvHeapInit();
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+
+ /* Check the requested block size is not so large that the top bit is
+ set. The top bit of the block size member of the BlockLink_t structure
+ is used to determine who owns the block - the application or the
+ kernel, so it must be free. */
+ if( ( xWantedSize & xBlockAllocatedBit ) == 0 )
+ {
+ /* The wanted size is increased so it can contain a BlockLink_t
+ structure in addition to the requested amount of bytes. */
+ if( xWantedSize > 0 )
+ {
+ xWantedSize += xHeapStructSize;
+
+ /* Ensure that blocks are always aligned to the required number
+ of bytes. */
+ if( ( xWantedSize & portBYTE_ALIGNMENT_MASK ) != 0x00 )
+ {
+ /* Byte alignment required. */
+ xWantedSize += ( portBYTE_ALIGNMENT - ( xWantedSize & portBYTE_ALIGNMENT_MASK ) );
+ configASSERT( ( xWantedSize & portBYTE_ALIGNMENT_MASK ) == 0 );
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+
+ if( ( xWantedSize > 0 ) && ( xWantedSize <= xFreeBytesRemaining ) )
+ {
+ /* Traverse the list from the start (lowest address) block until
+ one of adequate size is found. */
+ pxPreviousBlock = &xStart;
+ pxBlock = xStart.pxNextFreeBlock;
+ while( ( pxBlock->xBlockSize < xWantedSize ) && ( pxBlock->pxNextFreeBlock != NULL ) )
+ {
+ pxPreviousBlock = pxBlock;
+ pxBlock = pxBlock->pxNextFreeBlock;
+ }
+
+ /* If the end marker was reached then a block of adequate size
+ was not found. */
+ if( pxBlock != pxEnd )
+ {
+ /* Return the memory space pointed to - jumping over the
+ BlockLink_t structure at its start. */
+ pvReturn = ( void * ) ( ( ( uint8_t * ) pxPreviousBlock->pxNextFreeBlock ) + xHeapStructSize );
+
+ /* This block is being returned for use so must be taken out
+ of the list of free blocks. */
+ pxPreviousBlock->pxNextFreeBlock = pxBlock->pxNextFreeBlock;
+
+ /* If the block is larger than required it can be split into
+ two. */
+ if( ( pxBlock->xBlockSize - xWantedSize ) > heapMINIMUM_BLOCK_SIZE )
+ {
+ /* This block is to be split into two. Create a new
+ block following the number of bytes requested. The void
+ cast is used to prevent byte alignment warnings from the
+ compiler. */
+ pxNewBlockLink = ( void * ) ( ( ( uint8_t * ) pxBlock ) + xWantedSize );
+ configASSERT( ( ( ( size_t ) pxNewBlockLink ) & portBYTE_ALIGNMENT_MASK ) == 0 );
+
+ /* Calculate the sizes of two blocks split from the
+ single block. */
+ pxNewBlockLink->xBlockSize = pxBlock->xBlockSize - xWantedSize;
+ pxBlock->xBlockSize = xWantedSize;
+
+ /* Insert the new block into the list of free blocks. */
+ prvInsertBlockIntoFreeList( pxNewBlockLink );
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+
+ xFreeBytesRemaining -= pxBlock->xBlockSize;
+
+ if( xFreeBytesRemaining < xMinimumEverFreeBytesRemaining )
+ {
+ xMinimumEverFreeBytesRemaining = xFreeBytesRemaining;
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+
+ /* The block is being returned - it is allocated and owned
+ by the application and has no "next" block. */
+ pxBlock->xBlockSize |= xBlockAllocatedBit;
+ pxBlock->pxNextFreeBlock = NULL;
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+
+ traceMALLOC( pvReturn, xWantedSize );
+ }
+ ( void ) xTaskResumeAll();
+
+ #if( configUSE_MALLOC_FAILED_HOOK == 1 )
+ {
+ if( pvReturn == NULL )
+ {
+ extern void vApplicationMallocFailedHook( void );
+ vApplicationMallocFailedHook();
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+ }
+ #endif
+
+ configASSERT( ( ( ( size_t ) pvReturn ) & ( size_t ) portBYTE_ALIGNMENT_MASK ) == 0 );
+ return pvReturn;
+}
+/*-----------------------------------------------------------*/
+
+void vPortFree( void *pv )
+{
+uint8_t *puc = ( uint8_t * ) pv;
+BlockLink_t *pxLink;
+
+ if( pv != NULL )
+ {
+ /* The memory being freed will have an BlockLink_t structure immediately
+ before it. */
+ puc -= xHeapStructSize;
+
+ /* This casting is to keep the compiler from issuing warnings. */
+ pxLink = ( void * ) puc;
+
+ /* Check the block is actually allocated. */
+ configASSERT( ( pxLink->xBlockSize & xBlockAllocatedBit ) != 0 );
+ configASSERT( pxLink->pxNextFreeBlock == NULL );
+
+ if( ( pxLink->xBlockSize & xBlockAllocatedBit ) != 0 )
+ {
+ if( pxLink->pxNextFreeBlock == NULL )
+ {
+ /* The block is being returned to the heap - it is no longer
+ allocated. */
+ pxLink->xBlockSize &= ~xBlockAllocatedBit;
+
+ vTaskSuspendAll();
+ {
+ /* Add this block to the list of free blocks. */
+ xFreeBytesRemaining += pxLink->xBlockSize;
+ traceFREE( pv, pxLink->xBlockSize );
+ prvInsertBlockIntoFreeList( ( ( BlockLink_t * ) pxLink ) );
+ }
+ ( void ) xTaskResumeAll();
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+ }
+}
+/*-----------------------------------------------------------*/
+
+size_t xPortGetFreeHeapSize( void )
+{
+ return xFreeBytesRemaining;
+}
+/*-----------------------------------------------------------*/
+
+size_t xPortGetMinimumEverFreeHeapSize( void )
+{
+ return xMinimumEverFreeBytesRemaining;
+}
+/*-----------------------------------------------------------*/
+
+void vPortInitialiseBlocks( void )
+{
+ /* This just exists to keep the linker quiet. */
+}
+/*-----------------------------------------------------------*/
+
+static void prvHeapInit( void )
+{
+BlockLink_t *pxFirstFreeBlock;
+uint8_t *pucAlignedHeap;
+size_t uxAddress;
+size_t xTotalHeapSize = configTOTAL_HEAP_SIZE;
+
+ /* Ensure the heap starts on a correctly aligned boundary. */
+ uxAddress = ( size_t ) ucHeap;
+
+ if( ( uxAddress & portBYTE_ALIGNMENT_MASK ) != 0 )
+ {
+ uxAddress += ( portBYTE_ALIGNMENT - 1 );
+ uxAddress &= ~( ( size_t ) portBYTE_ALIGNMENT_MASK );
+ xTotalHeapSize -= uxAddress - ( size_t ) ucHeap;
+ }
+
+ pucAlignedHeap = ( uint8_t * ) uxAddress;
+
+ /* xStart is used to hold a pointer to the first item in the list of free
+ blocks. The void cast is used to prevent compiler warnings. */
+ xStart.pxNextFreeBlock = ( void * ) pucAlignedHeap;
+ xStart.xBlockSize = ( size_t ) 0;
+
+ /* pxEnd is used to mark the end of the list of free blocks and is inserted
+ at the end of the heap space. */
+ uxAddress = ( ( size_t ) pucAlignedHeap ) + xTotalHeapSize;
+ uxAddress -= xHeapStructSize;
+ uxAddress &= ~( ( size_t ) portBYTE_ALIGNMENT_MASK );
+ pxEnd = ( void * ) uxAddress;
+ pxEnd->xBlockSize = 0;
+ pxEnd->pxNextFreeBlock = NULL;
+
+ /* To start with there is a single free block that is sized to take up the
+ entire heap space, minus the space taken by pxEnd. */
+ pxFirstFreeBlock = ( void * ) pucAlignedHeap;
+ pxFirstFreeBlock->xBlockSize = uxAddress - ( size_t ) pxFirstFreeBlock;
+ pxFirstFreeBlock->pxNextFreeBlock = pxEnd;
+
+ /* Only one block exists - and it covers the entire usable heap space. */
+ xMinimumEverFreeBytesRemaining = pxFirstFreeBlock->xBlockSize;
+ xFreeBytesRemaining = pxFirstFreeBlock->xBlockSize;
+
+ /* Work out the position of the top bit in a size_t variable. */
+ xBlockAllocatedBit = ( ( size_t ) 1 ) << ( ( sizeof( size_t ) * heapBITS_PER_BYTE ) - 1 );
+}
+/*-----------------------------------------------------------*/
+
+static void prvInsertBlockIntoFreeList( BlockLink_t *pxBlockToInsert )
+{
+BlockLink_t *pxIterator;
+uint8_t *puc;
+
+ /* Iterate through the list until a block is found that has a higher address
+ than the block being inserted. */
+ for( pxIterator = &xStart; pxIterator->pxNextFreeBlock < pxBlockToInsert; pxIterator = pxIterator->pxNextFreeBlock )
+ {
+ /* Nothing to do here, just iterate to the right position. */
+ }
+
+ /* Do the block being inserted, and the block it is being inserted after
+ make a contiguous block of memory? */
+ puc = ( uint8_t * ) pxIterator;
+ if( ( puc + pxIterator->xBlockSize ) == ( uint8_t * ) pxBlockToInsert )
+ {
+ pxIterator->xBlockSize += pxBlockToInsert->xBlockSize;
+ pxBlockToInsert = pxIterator;
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+
+ /* Do the block being inserted, and the block it is being inserted before
+ make a contiguous block of memory? */
+ puc = ( uint8_t * ) pxBlockToInsert;
+ if( ( puc + pxBlockToInsert->xBlockSize ) == ( uint8_t * ) pxIterator->pxNextFreeBlock )
+ {
+ if( pxIterator->pxNextFreeBlock != pxEnd )
+ {
+ /* Form one big block from the two blocks. */
+ pxBlockToInsert->xBlockSize += pxIterator->pxNextFreeBlock->xBlockSize;
+ pxBlockToInsert->pxNextFreeBlock = pxIterator->pxNextFreeBlock->pxNextFreeBlock;
+ }
+ else
+ {
+ pxBlockToInsert->pxNextFreeBlock = pxEnd;
+ }
+ }
+ else
+ {
+ pxBlockToInsert->pxNextFreeBlock = pxIterator->pxNextFreeBlock;
+ }
+
+ /* If the block being inserted plugged a gab, so was merged with the block
+ before and the block after, then it's pxNextFreeBlock pointer will have
+ already been set, and should not be set here as that would make it point
+ to itself. */
+ if( pxIterator != pxBlockToInsert )
+ {
+ pxIterator->pxNextFreeBlock = pxBlockToInsert;
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+}
+
|