MemoryBlock GetMemoryBlock(IntPtr origin)
{
IntPtr minAddr = IntPtr.Zero;
IntPtr maxAddr = IntPtr.Zero;
MemoryBlock result = null;
SYSTEM_INFO si = new SYSTEM_INFO();
GetSystemInfo(ref si);
if (IntPtr.Size == 8)
{
minAddr = si.lpMinimumApplicationAddress;
maxAddr = si.lpMaximumApplicationAddress;
if ((ulong)origin > MAX_MEMORY_RANGE && (ulong)minAddr < (ulong)origin - MAX_MEMORY_RANGE)
{
minAddr = (IntPtr)((ulong)origin - MAX_MEMORY_RANGE);
}
if ((ulong)maxAddr > (ulong)origin + MAX_MEMORY_RANGE)
{
maxAddr = (IntPtr)((ulong)origin + MAX_MEMORY_RANGE);
}
maxAddr = (IntPtr)((ulong)maxAddr - MEMORY_BLOCK_SIZE - 1);
}
foreach (var memoryBlock in memoryBlocks)
{
if (IntPtr.Size == 8 && ((ulong)memoryBlock.BaseAddress < (ulong)minAddr || (ulong)memoryBlock.BaseAddress >= (ulong)maxAddr))
{
continue;
}
if (!memoryBlock.IsFull())
{
return(memoryBlock);
}
}
//Couldn't find a free block, lets allocate another
if (IntPtr.Size == 8)
{
IntPtr alloc = origin;
while ((ulong)alloc >= (ulong)minAddr)
{
alloc = FindPrevFreeRegion(alloc, minAddr, si.dwAllocationGranularity);
if (alloc == IntPtr.Zero)
{
break;
}
IntPtr baseAddr = VirtualAlloc(alloc, (IntPtr)MEMORY_BLOCK_SIZE, AllocationType.Commit | AllocationType.Reserve, MemoryProtection.ExecuteReadWrite);
if (baseAddr != IntPtr.Zero)
{
result = new MemoryBlock(baseAddr);
break;
}
}
if (result == null)
{
alloc = origin;
while ((ulong)alloc <= (ulong)maxAddr)
{
alloc = FindNextFreeRegion(alloc, maxAddr, si.dwAllocationGranularity);
if (alloc == IntPtr.Zero)
{
break;
}
IntPtr baseAddr = VirtualAlloc(alloc, (IntPtr)MEMORY_BLOCK_SIZE, AllocationType.Commit | AllocationType.Reserve, MemoryProtection.ExecuteReadWrite);
if (baseAddr != IntPtr.Zero)
{
result = new MemoryBlock(baseAddr);
break;
}
}
}
}
else
{
IntPtr baseAddr = VirtualAlloc(IntPtr.Zero, (IntPtr)MEMORY_BLOCK_SIZE, AllocationType.Commit | AllocationType.Reserve, MemoryProtection.ExecuteReadWrite);
if (baseAddr == IntPtr.Zero)
{
throw new OutOfMemoryException("Failed to allocate new block of memory");
}
result = new MemoryBlock(baseAddr);
}
if (result == null)
{
throw new OutOfMemoryException("Failed to allocate new block of memory");
}
memoryBlocks.Add(result);
return(result);
}
public MemorySlot(MemoryBlock ownerBlock, IntPtr address, int index)
{
this.ownerBlock = ownerBlock;
Address = address;
Index = index;
}
public MemorySlot AllocateBuffer(IntPtr origin)
{
MemoryBlock block = GetMemoryBlock(origin);
return(block.AllocateSlot());
}
