diff --git a/src/FreeRTOS/heap_4_infinitime.c b/src/FreeRTOS/heap_4_infinitime.c index 917d3596..31f34602 100644 --- a/src/FreeRTOS/heap_4_infinitime.c +++ b/src/FreeRTOS/heap_4_infinitime.c @@ -31,10 +31,14 @@ * (coalescences) adjacent memory blocks as they are freed, and in so doing * limits memory fragmentation. * +* This implementation is based on heap_4.c and add the function pvPortRealloc() +* to the original implementation. +* * 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 +#include /* 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 @@ -442,3 +446,72 @@ static void prvInsertBlockIntoFreeList( BlockLink_t *pxBlockToInsert ) } } +/*-----------------------------------------------------------*/ + +void *pvPortRealloc( void *pv, size_t xWantedSize ) +{ + size_t move_size; + size_t block_size; + BlockLink_t* pxLink; + void* pvReturn = NULL; + uint8_t* puc = (uint8_t*) pv; + + if (xWantedSize > 0) + { + 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 allocate block + if ((pxLink->xBlockSize & xBlockAllocatedBit) != 0) + { + // The block is being returned to the heap - it is no longer allocated. + block_size = (pxLink->xBlockSize & ~xBlockAllocatedBit) - xHeapStructSize; + + // Allocate a new buffer + pvReturn = pvPortMalloc(xWantedSize); + + // Check creation and determine the data size to be copied to the new buffer + if (pvReturn != NULL) + { + if (block_size < xWantedSize) + { + move_size = block_size; + } + else + { + move_size = xWantedSize; + } + + // Copy the data from the old buffer to the new one + memcpy(pvReturn, pv, move_size); + + // Free the old buffer + vPortFree(pv); + } + } + else + { + // pv does not point to a valid memory buffer. Allocate a new one + pvReturn = pvPortMalloc(xWantedSize); + } + } + else + { + // pv points to NULL. Allocate a new buffer. + pvReturn = pvPortMalloc(xWantedSize); + } + } + else + { + // Zero bytes requested, do nothing (according to libc, this behavior implementation defined) + pvReturn = NULL; + } + + // Exit with memory block + return pvReturn; +}