ModernUO/Projects/Server/NativeReader.cs
Kamron Batman 9729b5a7b0
fix(map): Fixes map diffs (Old Haven/Minax) (#720)
* Fixes reading map/static diffs.
2021-08-22 23:35:18 -07:00

62 lines
2.3 KiB
C#

using System;
using System.IO;
using System.Runtime.InteropServices;
using System.Threading;
namespace Server
{
public static class NativeReader
{
private static readonly INativeReader m_NativeReader;
static NativeReader() => m_NativeReader = Core.Unix ? new NativeReaderUnix() : new NativeReaderWin32();
public static unsafe int Read(FileStream source, void* buffer, int length) => Read(source, buffer, 0, length);
public static unsafe int Read(FileStream source, void* buffer, int bufferIndex, int length) =>
m_NativeReader.Read(source, buffer, bufferIndex, length);
}
public interface INativeReader
{
unsafe int Read(FileStream source, void* buffer, int bufferIndex, int length);
}
public sealed class NativeReaderWin32 : INativeReader
{
internal class UnsafeNativeMethods
{
[DllImport("kernel32")]
internal static extern unsafe bool ReadFile(IntPtr hFile, void* lpBuffer, uint nNumberOfBytesToRead, ref uint lpNumberOfBytesRead, NativeOverlapped* lpOverlapped);
}
public unsafe int Read(FileStream source, void* buffer, int bufferIndex, int length) => InternalRead(source, buffer, bufferIndex, length);
internal static unsafe int InternalRead(FileStream source, void* buffer, int bufferIndex, int length)
{
var byteCount = 0U;
if (UnsafeNativeMethods.ReadFile(source.SafeFileHandle!.DangerousGetHandle(), (byte*)buffer + bufferIndex, (uint)length, ref byteCount, null))
{
return (int)byteCount;
}
return -1;
}
}
public sealed class NativeReaderUnix : INativeReader
{
internal class UnsafeNativeMethods
{
[DllImport("libc")]
internal static extern unsafe int read(IntPtr ptr, void* buffer, int length);
}
public unsafe int Read(FileStream source, void* buffer, int bufferIndex, int length) =>
InternalRead(source, buffer, bufferIndex, length);
internal unsafe int InternalRead(FileStream source, void* buffer, int bufferIndex, int length) =>
UnsafeNativeMethods.read(source.SafeFileHandle.DangerousGetHandle(), (byte*)buffer + bufferIndex, length);
}
}