/// <summary>
/// 向指定内存段的指定偏移处回写一个void*
/// </summary>
/// <param name="position">回写位置</param>
/// <param name="value">回写值</param>
/// <param name="length">回写长度</param>
public void WriteBackMemory(MemoryPosition position, void *value, uint length)
{
//well-done, needn't cross memory segments.
if (MemoryAllotter.SegmentSize - position.SegmentOffset == 0)
{
position.SegmentIndex++;
position.SegmentOffset = 0;
}
IMemorySegment segment = GetSegment(position.SegmentIndex);
int startSegmentIndex = position.SegmentIndex;
uint remainingSize = (MemoryAllotter.SegmentSize - position.SegmentOffset);
if (remainingSize >= length)
{
Buffer.MemoryCopy((void *)new IntPtr(value), (void *)new IntPtr(_segments[position.SegmentIndex].GetPointer() + position.SegmentOffset), length /*protective range*/, length);
}
//Native.Win32API.memcpy(new IntPtr(_segments[position.SegmentIndex].GetPointer() + position.SegmentOffset), new IntPtr(value), length);
else
{
uint trueRemainingSize = length;
uint continueSize = 0U;
do
{
Buffer.MemoryCopy(
(void *)new IntPtr((byte *)value + continueSize),
(void *)new IntPtr(segment.GetPointer() + (position.SegmentIndex - startSegmentIndex == 0 ? position.SegmentOffset : 0)),
MemoryAllotter.SegmentSize /*protective range*/,
(remainingSize < trueRemainingSize ? remainingSize : (trueRemainingSize < MemoryAllotter.SegmentSize ? trueRemainingSize : MemoryAllotter.SegmentSize)));
//Native.Win32API.memcpy(
// new IntPtr(segment.GetPointer() +(position.SegmentIndex - startSegmentIndex == 0 ? position.SegmentOffset : 0)),
// new IntPtr((byte*)value + continueSize),
// (remainingSize < trueRemainingSize? remainingSize: (trueRemainingSize < MemoryAllotter.SegmentSize? trueRemainingSize: MemoryAllotter.SegmentSize)));
if (trueRemainingSize <= remainingSize)
{
trueRemainingSize = 0U;
}
else
{
trueRemainingSize -= remainingSize;
}
segment = GetSegment(++position.SegmentIndex);
continueSize += remainingSize;
remainingSize = MemoryAllotter.SegmentSize;
} while (trueRemainingSize > 0U);
}
}
/// <summary>
/// 向指定内存段的指定偏移处回写一个uint32数值
/// </summary>
/// <param name="position">回写位置</param>
/// <param name="value">回写值</param>
public void WriteBackUInt32(MemoryPosition position, uint value)
{
//well-done, needn't cross memory segments.
uint remainingSize = (MemoryAllotter.SegmentSize - position.SegmentOffset);
if (remainingSize >= Size.UInt32)
{
*(uint *)(_segments[position.SegmentIndex].GetPointer() + position.SegmentOffset) = value;
}
else
{
uint trueRemainingSize = Size.UInt32;
byte *data = (byte *)&value;
if (remainingSize != 0U)
{
Buffer.MemoryCopy((void *)new IntPtr(data), (void *)new IntPtr(_segments[position.SegmentIndex].GetPointer() + position.SegmentOffset), remainingSize, remainingSize);
//Native.Win32API.memcpy(new IntPtr(_segments[position.SegmentIndex].GetPointer() + position.SegmentOffset), new IntPtr(data), remainingSize);
trueRemainingSize -= remainingSize;
}
//write at head.
Buffer.MemoryCopy((void *)new IntPtr(data + remainingSize), (void *)new IntPtr(_segments[position.SegmentIndex + 1].GetPointer()), MemoryAllotter.SegmentSize, trueRemainingSize);
//Native.Win32API.memcpy(new IntPtr(_segments[position.SegmentIndex + 1].GetPointer()), new IntPtr(data + remainingSize), trueRemainingSize);
}
}
/// <summary>
/// 计算截止位置与开始位置之间的距离
/// </summary>
/// <param name="segmentCount">内存段数量</param>
/// <param name="start">起始位置</param>
/// <param name="end">截止位置</param>
/// <returns>返回它们之间所差的距离</returns>
public static int CalcLength(int segmentCount, MemoryPosition start, MemoryPosition end)
{
return((int)(((end.SegmentIndex) * MemoryAllotter.SegmentSize + end.SegmentOffset) -
((start.SegmentIndex) * MemoryAllotter.SegmentSize + start.SegmentOffset)));
}