/// <summary>
/// Initializes a new allocator with an empty heap.
/// </summary>
/// <param name="heapAddress">The address where the heap will start.</param>
/// <param name="requester">A delegate to request more memory.</param>
public HeapAllocator(uint heapAddress, MemoryRequester requester)
{
this.heapAddress = heapAddress;
this.setEndMem = requester;
this.blocks = new List <HeapEntry>();
this.freeList = new List <HeapEntry>();
endMem = heapAddress;
heapExtent = 0;
}
/// <summary>
/// Initializes a new allocator from a previous saved heap state.
/// </summary>
/// <param name="savedHeap">A byte array describing the heap state,
/// as returned by the <see cref="Save"/> method.</param>
/// <param name="requester">A delegate to request more memory.</param>
public HeapAllocator(byte[] savedHeap, MemoryRequester requester)
{
this.heapAddress = BigEndian.ReadInt32(savedHeap, 0);
this.setEndMem = requester;
this.blocks = new List <HeapEntry>();
this.freeList = new List <HeapEntry>();
uint numBlocks = BigEndian.ReadInt32(savedHeap, 4);
blocks.Capacity = (int)numBlocks;
uint nextAddress = heapAddress;
for (uint i = 0; i < numBlocks; i++)
{
uint start = BigEndian.ReadInt32(savedHeap, 8 * i + 8);
uint length = BigEndian.ReadInt32(savedHeap, 8 * i + 12);
blocks.Add(new HeapEntry(start, length));
if (nextAddress < start)
{
freeList.Add(new HeapEntry(nextAddress, start - nextAddress));
}
nextAddress = start + length;
}
endMem = nextAddress;
heapExtent = nextAddress - heapAddress;
if (setEndMem(endMem) == false)
{
throw new ArgumentException("Can't allocate VM memory to fit saved heap");
}
blocks.Sort(entryComparer);
freeList.Sort(entryComparer);
}
