/*!
* \brief Add a new memory region to the heap.
*
* This function can be called more than once to manage non-continous
* memory regions. It is automatically called by Nut/OS during
* initialization.
*
* \param addr Start address of the memory region.
* \param size Number of bytes of the memory region.
*/
void NutHeapRootAdd(HEAPNODE ** root, void *addr, size_t size)
{
HEAPNODE *node = (HEAPNODE *) NUTMEM_TOP_ALIGN((uintptr_t) addr);
node->hn_size = NUTMEM_BOTTOM_ALIGN(size - ((uintptr_t) node - (uintptr_t) addr));
#ifdef NUTDEBUG_HEAP
NutHeapDebugRootFree(root, PrepareUserArea(node), NULL, 0);
#else
NutHeapRootFree(root, PrepareUserArea(node));
#endif
}
/*!
* \brief Return a block to heap memory.
*
* This function simply calls NutHeapFree(). It overrides the function
* of the runtime library, when the application is linked with nutcrt or
* nutcrtf.
*
* \param p Points to a memory block previously allocated
* through a call to malloc().
*/
void dbg_free(void *p, CONST char *file, int line)
{
NutHeapDebugRootFree(&heapFreeList, p, file, line);
}
void *NutHeapRootRealloc(HEAPNODE ** root, void *block, size_t size)
#endif
{
HEAPNODE *node;
HEAPNODE **npp;
HEAPNODE *fnode;
void *newmem;
#ifdef NUTDEBUG_HEAP
/* With NULL pointer the call is equivalent to alloc. */
if (block == NULL) {
return NutHeapDebugRootAlloc(root, size, file, line);
}
/* With zero size the call is equivalent to free. */
if (size == 0) {
if (NutHeapDebugRootFree(root, block, file, line)) {
return NULL;
}
return block;
}
/* Revive our node pointer. */
fnode = (HEAPNODE *) ((uintptr_t) block - (NUT_HEAP_OVERHEAD + NUTMEM_GUARD_BYTES));
/* Sanity check. */
if (DebugValidateUserArea(fnode, file, line)) {
return NULL;
}
#else
if (block == NULL) {
return NutHeapRootAlloc(root, size);
}
if (size == 0) {
if (NutHeapRootFree(root, block)) {
return NULL;
}
return block;
}
fnode = (HEAPNODE *) ((uintptr_t) block - (NUT_HEAP_OVERHEAD + NUTMEM_GUARD_BYTES));
if (ValidateUserArea(fnode)) {
return NULL;
}
#endif
/* Determine the minimum size. Add optional guard and alignment bytes.
Make sure that a HEAPNODE structure fits. */
size += NUT_HEAP_OVERHEAD + NUTMEM_GUARD_BYTES * 2;
if (size < sizeof(HEAPNODE)) {
size = sizeof(HEAPNODE);
}
size = NUTMEM_TOP_ALIGN(size);
/*
* Expansion.
*/
if (size > fnode->hn_size) {
size_t size_miss = size - fnode->hn_size;
/* Find the free node following next. */
node = *root;
npp = root;
while (node && node < fnode) {
npp = &node->hn_next;
node = node->hn_next;
}
/* If we found a node and if this node is large enough and
if it directly follows without a gap, then use it. */
if (node && node->hn_size >= size_miss && /* */
(uintptr_t) fnode + fnode->hn_size == (uintptr_t) node) {
/* Check if the following node is large enough to be split. */
if (node->hn_size - size_miss >= NUTMEM_HEAPNODE_MIN) {
/* Adjust the allocated size. */
fnode->hn_size += size_miss;
/* Insert the remaining part into the free list. */
*npp = (HEAPNODE *) ((uintptr_t) node + size_miss);
/* Due to possible overlapping it is important to set
the pointer first, then the size. */
(*npp)->hn_next = node->hn_next;
(*npp)->hn_size = node->hn_size - size_miss;
PrepareUserArea(fnode);
} else {
/* Adjust the allocated size. */
fnode->hn_size += node->hn_size;
PrepareUserArea(fnode);
/* Remove the merged node from the free list. */
*npp = node->hn_next;
}
/* Return the original pointer. */
return block;
}
/* Relocate if no sufficiently large block follows. */
#ifdef NUTDEBUG_HEAP
newmem = NutHeapDebugRootAlloc(root, size, file, line);
#else
newmem = NutHeapRootAlloc(root, size);
#endif
if (newmem) {
memcpy(newmem, block,
fnode->hn_size - NUT_HEAP_OVERHEAD - 2 * NUTMEM_GUARD_BYTES);
#ifdef NUTDEBUG_HEAP
NutHeapDebugRootFree(root, block, file, line);
#else
NutHeapRootFree(root, block);
#endif
}
return newmem;
}
/*
* Reduction.
*/
if (size < fnode->hn_size - NUTMEM_HEAPNODE_MIN) {
/* Release the remaining part to the free list. */
node = (HEAPNODE *) ((uintptr_t) fnode + size);
node->hn_size = fnode->hn_size - size;
#ifdef NUTDEBUG_HEAP
NutHeapDebugRootFree(root, PrepareUserArea(node), NULL, 0);
#else
NutHeapRootFree(root, PrepareUserArea(node));
#endif
/* Adjust the allocated size. */
fnode->hn_size = size;
PrepareUserArea(fnode);
}
return block;
}