/* * FreeRTOS Kernel <DEVELOPMENT BRANCH> * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved. * * SPDX-License-Identifier: MIT * * 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. * * https://www.FreeRTOS.org * https://github.com/FreeRTOS * *//* ... */ /* * 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 https://www.FreeRTOS.org for more information. *//* ... */ #include <stdlib.h> #include <string.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 #ifndef configHEAP_CLEAR_MEMORY_ON_FREE #define configHEAP_CLEAR_MEMORY_ON_FREE 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 ) /* Max value that fits in a size_t type. */ #define heapSIZE_MAX ( ~( ( size_t ) 0 ) ) /* Check if multiplying a and b will result in overflow. */ #define heapMULTIPLY_WILL_OVERFLOW( a, b ) ( ( ( a ) > 0 ) && ( ( b ) > ( heapSIZE_MAX / ( a ) ) ) ) /* Check if adding a and b will result in overflow. */ #define heapADD_WILL_OVERFLOW( a, b ) ( ( a ) > ( heapSIZE_MAX - ( b ) ) ) /* Check if the subtraction operation ( a - b ) will result in underflow. */ #define heapSUBTRACT_WILL_UNDERFLOW( a, b ) ( ( a ) < ( b ) ) /* MSB of the xBlockSize member of an BlockLink_t structure is used to track * the allocation status of a block. When MSB of 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. *//* ... */ #define heapBLOCK_ALLOCATED_BITMASK ( ( ( size_t ) 1 ) << ( ( sizeof( size_t ) * heapBITS_PER_BYTE ) - 1 ) ) #define heapBLOCK_SIZE_IS_VALID( xBlockSize ) ( ( ( xBlockSize ) & heapBLOCK_ALLOCATED_BITMASK ) == 0 ) #define heapBLOCK_IS_ALLOCATED( pxBlock ) ( ( ( pxBlock->xBlockSize ) & heapBLOCK_ALLOCATED_BITMASK ) != 0 ) #define heapALLOCATE_BLOCK( pxBlock ) ( ( pxBlock->xBlockSize ) |= heapBLOCK_ALLOCATED_BITMASK ) #define heapFREE_BLOCK( pxBlock ) ( ( pxBlock->xBlockSize ) &= ~heapBLOCK_ALLOCATED_BITMASK ) 11 defines /*-----------------------------------------------------------*/ /* 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 PRIVILEGED_DATA 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; /* Setting configENABLE_HEAP_PROTECTOR to 1 enables heap block pointers * protection using an application supplied canary value to catch heap * corruption should a heap buffer overflow occur. *//* ... */ #if ( configENABLE_HEAP_PROTECTOR == 1 ) /** * @brief Application provided function to get a random value to be used as canary. * * @param pxHeapCanary [out] Output parameter to return the canary value. *//* ... */ extern void vApplicationGetRandomHeapCanary( portPOINTER_SIZE_TYPE * pxHeapCanary ); /* Canary value for protecting internal heap pointers. */ PRIVILEGED_DATA static portPOINTER_SIZE_TYPE xHeapCanary; /* Macro to load/store BlockLink_t pointers to memory. By XORing the * pointers with a random canary value, heap overflows will result * in randomly unpredictable pointer values which will be caught by * heapVALIDATE_BLOCK_POINTER assert. *//* ... */ #define heapPROTECT_BLOCK_POINTER( pxBlock ) ( ( BlockLink_t * ) ( ( ( portPOINTER_SIZE_TYPE ) ( pxBlock ) ) ^ xHeapCanary ) ) /* ... */#else #define heapPROTECT_BLOCK_POINTER( pxBlock ) ( pxBlock ) /* ... */ #endif /* configENABLE_HEAP_PROTECTOR */ /* Assert that a heap block pointer is within the heap bounds. */ #define heapVALIDATE_BLOCK_POINTER( pxBlock ) \ configASSERT( ( ( uint8_t * ) ( pxBlock ) >= &( ucHeap[ 0 ] ) ) && \ ( ( uint8_t * ) ( pxBlock ) <= &( ucHeap[ configTOTAL_HEAP_SIZE - 1 ] ) ) )... /*-----------------------------------------------------------*/ /* * 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 ) PRIVILEGED_FUNCTION; /* * Called automatically to setup the required heap structures the first time * pvPortMalloc() is called. *//* ... */ static void prvHeapInit( void ) PRIVILEGED_FUNCTION; /*-----------------------------------------------------------*/ /* 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. */ PRIVILEGED_DATA static BlockLink_t xStart; PRIVILEGED_DATA static BlockLink_t * pxEnd = NULL; /* Keeps track of the number of calls to allocate and free memory as well as the * number of free bytes remaining, but says nothing about fragmentation. *//* ... */ PRIVILEGED_DATA static size_t xFreeBytesRemaining = ( size_t ) 0U; PRIVILEGED_DATA static size_t xMinimumEverFreeBytesRemaining = ( size_t ) 0U; PRIVILEGED_DATA static size_t xNumberOfSuccessfulAllocations = ( size_t ) 0U; PRIVILEGED_DATA static size_t xNumberOfSuccessfulFrees = ( size_t ) 0U; /*-----------------------------------------------------------*/ void * pvPortMalloc( size_t xWantedSize ) { BlockLink_t * pxBlock; BlockLink_t * pxPreviousBlock; BlockLink_t * pxNewBlockLink; void * pvReturn = NULL; size_t xAdditionalRequiredSize; size_t xAllocatedBlockSize = 0; if( xWantedSize > 0 ) { /* The wanted size must be increased so it can contain a BlockLink_t * structure in addition to the requested amount of bytes. *//* ... */ if( heapADD_WILL_OVERFLOW( xWantedSize, xHeapStructSize ) == 0 ) { xWantedSize += xHeapStructSize; /* Ensure that blocks are always aligned to the required number * of bytes. *//* ... */ if( ( xWantedSize & portBYTE_ALIGNMENT_MASK ) != 0x00 ) { /* Byte alignment required. */ xAdditionalRequiredSize = portBYTE_ALIGNMENT - ( xWantedSize & portBYTE_ALIGNMENT_MASK ); if( heapADD_WILL_OVERFLOW( xWantedSize, xAdditionalRequiredSize ) == 0 ) { xWantedSize += xAdditionalRequiredSize; }if (heapADD_WILL_OVERFLOW( xWantedSize, xAdditionalRequiredSize ) == 0) { ... } else { xWantedSize = 0; }else { ... } }if (( xWantedSize & portBYTE_ALIGNMENT_MASK ) != 0x00) { ... } else { mtCOVERAGE_TEST_MARKER(); }else { ... } }if (heapADD_WILL_OVERFLOW( xWantedSize, xHeapStructSize ) == 0) { ... } else { xWantedSize = 0; }else { ... } }if (xWantedSize > 0) { ... } else { mtCOVERAGE_TEST_MARKER(); }else { ... } 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(); }if (pxEnd == NULL) { ... } else { mtCOVERAGE_TEST_MARKER(); }else { ... } /* Check the block size we are trying to allocate 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( heapBLOCK_SIZE_IS_VALID( xWantedSize ) != 0 ) { if( ( xWantedSize > 0 ) && ( xWantedSize <= xFreeBytesRemaining ) ) { /* Traverse the list from the start (lowest address) block until * one of adequate size is found. *//* ... */ pxPreviousBlock = &xStart; pxBlock = heapPROTECT_BLOCK_POINTER( xStart.pxNextFreeBlock ); heapVALIDATE_BLOCK_POINTER( pxBlock ); while( ( pxBlock->xBlockSize < xWantedSize ) && ( pxBlock->pxNextFreeBlock != heapPROTECT_BLOCK_POINTER( NULL ) ) ) { pxPreviousBlock = pxBlock; pxBlock = heapPROTECT_BLOCK_POINTER( pxBlock->pxNextFreeBlock ); heapVALIDATE_BLOCK_POINTER( pxBlock ); }while (( pxBlock->xBlockSize < xWantedSize ) && ( pxBlock->pxNextFreeBlock != heapPROTECT_BLOCK_POINTER( NULL ) )) { ... } /* 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 * ) heapPROTECT_BLOCK_POINTER( pxPreviousBlock->pxNextFreeBlock ) ) + xHeapStructSize ); heapVALIDATE_BLOCK_POINTER( pvReturn ); /* 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. *//* ... */ configASSERT( heapSUBTRACT_WILL_UNDERFLOW( pxBlock->xBlockSize, xWantedSize ) == 0 ); 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. */ pxNewBlockLink->pxNextFreeBlock = pxPreviousBlock->pxNextFreeBlock; pxPreviousBlock->pxNextFreeBlock = heapPROTECT_BLOCK_POINTER( pxNewBlockLink ); }if (( pxBlock->xBlockSize - xWantedSize ) > heapMINIMUM_BLOCK_SIZE) { ... } else { mtCOVERAGE_TEST_MARKER(); }else { ... } xFreeBytesRemaining -= pxBlock->xBlockSize; if( xFreeBytesRemaining < xMinimumEverFreeBytesRemaining ) { xMinimumEverFreeBytesRemaining = xFreeBytesRemaining; }if (xFreeBytesRemaining < xMinimumEverFreeBytesRemaining) { ... } else { mtCOVERAGE_TEST_MARKER(); }else { ... } xAllocatedBlockSize = pxBlock->xBlockSize; /* The block is being returned - it is allocated and owned * by the application and has no "next" block. *//* ... */ heapALLOCATE_BLOCK( pxBlock ); pxBlock->pxNextFreeBlock = heapPROTECT_BLOCK_POINTER( NULL ); xNumberOfSuccessfulAllocations++; }if (pxBlock != pxEnd) { ... } else { mtCOVERAGE_TEST_MARKER(); }else { ... } }if (( xWantedSize > 0 ) && ( xWantedSize <= xFreeBytesRemaining )) { ... } else { mtCOVERAGE_TEST_MARKER(); }else { ... } }if (heapBLOCK_SIZE_IS_VALID( xWantedSize ) != 0) { ... } else { mtCOVERAGE_TEST_MARKER(); }else { ... } traceMALLOC( pvReturn, xAllocatedBlockSize ); /* Prevent compiler warnings when trace macros are not used. */ ( void ) xAllocatedBlockSize; ...} ( void ) xTaskResumeAll(); #if ( configUSE_MALLOC_FAILED_HOOK == 1 ) { if( pvReturn == NULL ) { vApplicationMallocFailedHook(); }if (pvReturn == NULL) { ... } else { mtCOVERAGE_TEST_MARKER(); }else { ... } ...}/* ... */ #endif /* if ( configUSE_MALLOC_FAILED_HOOK == 1 ) */ 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; heapVALIDATE_BLOCK_POINTER( pxLink ); configASSERT( heapBLOCK_IS_ALLOCATED( pxLink ) != 0 ); configASSERT( pxLink->pxNextFreeBlock == heapPROTECT_BLOCK_POINTER( NULL ) ); if( heapBLOCK_IS_ALLOCATED( pxLink ) != 0 ) { if( pxLink->pxNextFreeBlock == heapPROTECT_BLOCK_POINTER( NULL ) ) { /* The block is being returned to the heap - it is no longer * allocated. *//* ... */ heapFREE_BLOCK( pxLink ); #if ( configHEAP_CLEAR_MEMORY_ON_FREE == 1 ) { /* Check for underflow as this can occur if xBlockSize is * overwritten in a heap block. *//* ... */ if( heapSUBTRACT_WILL_UNDERFLOW( pxLink->xBlockSize, xHeapStructSize ) == 0 ) { ( void ) memset( puc + xHeapStructSize, 0, pxLink->xBlockSize - xHeapStructSize ); }if (heapSUBTRACT_WILL_UNDERFLOW( pxLink->xBlockSize, xHeapStructSize ) == 0) { ... } ...}/* ... */ #endif vTaskSuspendAll(); { /* Add this block to the list of free blocks. */ xFreeBytesRemaining += pxLink->xBlockSize; traceFREE( pv, pxLink->xBlockSize ); prvInsertBlockIntoFreeList( ( ( BlockLink_t * ) pxLink ) ); xNumberOfSuccessfulFrees++; ...} ( void ) xTaskResumeAll(); }if (pxLink->pxNextFreeBlock == heapPROTECT_BLOCK_POINTER( NULL )) { ... } else { mtCOVERAGE_TEST_MARKER(); }else { ... } }if (heapBLOCK_IS_ALLOCATED( pxLink ) != 0) { ... } else { mtCOVERAGE_TEST_MARKER(); }else { ... } }if (pv != NULL) { ... } }{ ... } /*-----------------------------------------------------------*/ size_t xPortGetFreeHeapSize( void ) { return xFreeBytesRemaining; }{ ... } /*-----------------------------------------------------------*/ size_t xPortGetMinimumEverFreeHeapSize( void ) { return xMinimumEverFreeBytesRemaining; }{ ... } /*-----------------------------------------------------------*/ void vPortInitialiseBlocks( void ) { /* This just exists to keep the linker quiet. */ }{ ... } /*-----------------------------------------------------------*/ void * pvPortCalloc( size_t xNum, size_t xSize ) { void * pv = NULL; if( heapMULTIPLY_WILL_OVERFLOW( xNum, xSize ) == 0 ) { pv = pvPortMalloc( xNum * xSize ); if( pv != NULL ) { ( void ) memset( pv, 0, xNum * xSize ); }if (pv != NULL) { ... } }if (heapMULTIPLY_WILL_OVERFLOW( xNum, xSize ) == 0) { ... } return pv; }{ ... } /*-----------------------------------------------------------*/ static void prvHeapInit( void ) /* PRIVILEGED_FUNCTION */ { BlockLink_t * pxFirstFreeBlock; portPOINTER_SIZE_TYPE uxStartAddress, uxEndAddress; size_t xTotalHeapSize = configTOTAL_HEAP_SIZE; /* Ensure the heap starts on a correctly aligned boundary. */ uxStartAddress = ( portPOINTER_SIZE_TYPE ) ucHeap; if( ( uxStartAddress & portBYTE_ALIGNMENT_MASK ) != 0 ) { uxStartAddress += ( portBYTE_ALIGNMENT - 1 ); uxStartAddress &= ~( ( portPOINTER_SIZE_TYPE ) portBYTE_ALIGNMENT_MASK ); xTotalHeapSize -= ( size_t ) ( uxStartAddress - ( portPOINTER_SIZE_TYPE ) ucHeap ); }if (( uxStartAddress & portBYTE_ALIGNMENT_MASK ) != 0) { ... } #if ( configENABLE_HEAP_PROTECTOR == 1 ) { vApplicationGetRandomHeapCanary( &( xHeapCanary ) ); ...}/* ... */ #endif /* 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 * ) heapPROTECT_BLOCK_POINTER( uxStartAddress ); 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. *//* ... */ uxEndAddress = uxStartAddress + ( portPOINTER_SIZE_TYPE ) xTotalHeapSize; uxEndAddress -= ( portPOINTER_SIZE_TYPE ) xHeapStructSize; uxEndAddress &= ~( ( portPOINTER_SIZE_TYPE ) portBYTE_ALIGNMENT_MASK ); pxEnd = ( BlockLink_t * ) uxEndAddress; pxEnd->xBlockSize = 0; pxEnd->pxNextFreeBlock = heapPROTECT_BLOCK_POINTER( 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 = ( BlockLink_t * ) uxStartAddress; pxFirstFreeBlock->xBlockSize = ( size_t ) ( uxEndAddress - ( portPOINTER_SIZE_TYPE ) pxFirstFreeBlock ); pxFirstFreeBlock->pxNextFreeBlock = heapPROTECT_BLOCK_POINTER( pxEnd ); /* Only one block exists - and it covers the entire usable heap space. */ xMinimumEverFreeBytesRemaining = pxFirstFreeBlock->xBlockSize; xFreeBytesRemaining = pxFirstFreeBlock->xBlockSize; ...} /*-----------------------------------------------------------*/ static void prvInsertBlockIntoFreeList( BlockLink_t * pxBlockToInsert ) /* PRIVILEGED_FUNCTION */ { 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; heapPROTECT_BLOCK_POINTER( pxIterator->pxNextFreeBlock ) < pxBlockToInsert; pxIterator = heapPROTECT_BLOCK_POINTER( pxIterator->pxNextFreeBlock ) ) { /* Nothing to do here, just iterate to the right position. */ }for (pxIterator = &xStart; heapPROTECT_BLOCK_POINTER( pxIterator->pxNextFreeBlock ) < pxBlockToInsert; pxIterator = heapPROTECT_BLOCK_POINTER( pxIterator->pxNextFreeBlock )) { ... } if( pxIterator != &xStart ) { heapVALIDATE_BLOCK_POINTER( pxIterator ); }if (pxIterator != &xStart) { ... } /* 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; }if (( puc + pxIterator->xBlockSize ) == ( uint8_t * ) pxBlockToInsert) { ... } else { mtCOVERAGE_TEST_MARKER(); }else { ... } /* 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 * ) heapPROTECT_BLOCK_POINTER( pxIterator->pxNextFreeBlock ) ) { if( heapPROTECT_BLOCK_POINTER( pxIterator->pxNextFreeBlock ) != pxEnd ) { /* Form one big block from the two blocks. */ pxBlockToInsert->xBlockSize += heapPROTECT_BLOCK_POINTER( pxIterator->pxNextFreeBlock )->xBlockSize; pxBlockToInsert->pxNextFreeBlock = heapPROTECT_BLOCK_POINTER( pxIterator->pxNextFreeBlock )->pxNextFreeBlock; }if (heapPROTECT_BLOCK_POINTER( pxIterator->pxNextFreeBlock ) != pxEnd) { ... } else { pxBlockToInsert->pxNextFreeBlock = heapPROTECT_BLOCK_POINTER( pxEnd ); }else { ... } }if (( puc + pxBlockToInsert->xBlockSize ) == ( uint8_t * ) heapPROTECT_BLOCK_POINTER( pxIterator->pxNextFreeBlock )) { ... } else { pxBlockToInsert->pxNextFreeBlock = pxIterator->pxNextFreeBlock; }else { ... } /* If the block being inserted plugged a gap, 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 = heapPROTECT_BLOCK_POINTER( pxBlockToInsert ); }if (pxIterator != pxBlockToInsert) { ... } else { mtCOVERAGE_TEST_MARKER(); }else { ... } ...} /*-----------------------------------------------------------*/ void vPortGetHeapStats( HeapStats_t * pxHeapStats ) { BlockLink_t * pxBlock; size_t xBlocks = 0, xMaxSize = 0, xMinSize = portMAX_DELAY; /* portMAX_DELAY used as a portable way of getting the maximum value. */ vTaskSuspendAll(); { pxBlock = heapPROTECT_BLOCK_POINTER( xStart.pxNextFreeBlock ); /* pxBlock will be NULL if the heap has not been initialised. The heap * is initialised automatically when the first allocation is made. *//* ... */ if( pxBlock != NULL ) { while( pxBlock != pxEnd ) { /* Increment the number of blocks and record the largest block seen * so far. *//* ... */ xBlocks++; if( pxBlock->xBlockSize > xMaxSize ) { xMaxSize = pxBlock->xBlockSize; }if (pxBlock->xBlockSize > xMaxSize) { ... } if( pxBlock->xBlockSize < xMinSize ) { xMinSize = pxBlock->xBlockSize; }if (pxBlock->xBlockSize < xMinSize) { ... } /* Move to the next block in the chain until the last block is * reached. *//* ... */ pxBlock = heapPROTECT_BLOCK_POINTER( pxBlock->pxNextFreeBlock ); }while (pxBlock != pxEnd) { ... } }if (pxBlock != NULL) { ... } ...} ( void ) xTaskResumeAll(); pxHeapStats->xSizeOfLargestFreeBlockInBytes = xMaxSize; pxHeapStats->xSizeOfSmallestFreeBlockInBytes = xMinSize; pxHeapStats->xNumberOfFreeBlocks = xBlocks; taskENTER_CRITICAL(); { pxHeapStats->xAvailableHeapSpaceInBytes = xFreeBytesRemaining; pxHeapStats->xNumberOfSuccessfulAllocations = xNumberOfSuccessfulAllocations; pxHeapStats->xNumberOfSuccessfulFrees = xNumberOfSuccessfulFrees; pxHeapStats->xMinimumEverFreeBytesRemaining = xMinimumEverFreeBytesRemaining; ...} taskEXIT_CRITICAL(); }{ ... } /*-----------------------------------------------------------*/ /* * Reset the state in this file. This state is normally initialized at start up. * This function must be called by the application before restarting the * scheduler. *//* ... */ void vPortHeapResetState( void ) { pxEnd = NULL; xFreeBytesRemaining = ( size_t ) 0U; xMinimumEverFreeBytesRemaining = ( size_t ) 0U; xNumberOfSuccessfulAllocations = ( size_t ) 0U; xNumberOfSuccessfulFrees = ( size_t ) 0U; }{ ... } /*-----------------------------------------------------------*/