Heap: add heap_freeSpace(), a new function.

[bertos.git] / bertos / struct / heap.c

diff --git a/bertos/struct/heap.c b/bertos/struct/heap.c
index 27f8032567ae8945d70e6482a31a2c0afd90db85..1e4d60530336c7ae0f86e8cf891e7eeb44ccf63a 100644 (file)
--- a/bertos/struct/heap.c
+++ b/bertos/struct/heap.c
@@ -56,7 +56,7 @@ void heap_init(struct Heap* h, void* memory, size_t size)
        memset(memory, FREE_FILL_CODE, size);
        #endif
 
-       ASSERT2((((uintptr_t)memory % sizeof(heap_buf_t)) == 0),
+       ASSERT2(((size_t)memory % alignof(heap_buf_t)) == 0,
        "memory buffer is unaligned, please use the HEAP_DEFINE_BUF() macro to declare heap buffers!\n");
 
        /* Initialize heap with a single big chunk */
@@ -127,9 +127,9 @@ void heap_freemem(struct Heap* h, void *mem, size_t size)
        if (!size)
                size = sizeof(MemChunk);
 
-       /* Special case: first chunk in the free list */
+       /* Special cases: first chunk in the free list or memory completely full */
        ASSERT((uint8_t*)mem != (uint8_t*)h->FreeList);
-       if (((uint8_t *)mem) < ((uint8_t *)h->FreeList))
+       if (((uint8_t *)mem) < ((uint8_t *)h->FreeList) || !h->FreeList)
        {
                /* Insert memory block before the current free list head */
                prev = (MemChunk *)mem;
@@ -184,6 +184,25 @@ void heap_freemem(struct Heap* h, void *mem, size_t size)
        }
 }
 
+/**
+ * Returns the number of free bytes in a heap.
+ * \param h the heap to check.
+ *
+ * \note The returned value is the sum of all free memory regions 
+ *       in the heap.
+ *       Those regions are likely to be *not* contiguous,
+ *       so a successive allocation may fail even if the
+ *       requested amount of memory is lower than the current free space.
+ */
+size_t heap_freeSpace(struct Heap *h)
+{
+       size_t free_mem = 0;
+       for (MemChunck *chunk = h->FreeList; hunk; chunk = chunk->next)
+               free_mem += chunck->size;
+
+       return free_mem;
+}
+
 #if CONFIG_HEAP_MALLOC
 
 void *heap_malloc(struct Heap* h, size_t size)