obfuz/Plugins/dnlib/IO/UnalignedNativeMemoryDataSt...

85 lines
2.5 KiB
C#

// dnlib: See LICENSE.txt for more info
using System;
using System.Runtime.InteropServices;
using System.Text;
namespace dnlib.IO {
sealed unsafe class UnalignedNativeMemoryDataStream : DataStream {
readonly byte* data;
public UnalignedNativeMemoryDataStream(byte* data) => this.data = data;
public override void ReadBytes(uint offset, void* destination, int length) {
var ps = data + offset;
var pd = (byte*)destination;
int count = length / 4;
length = length % 4;
for (int i = 0; i < count; i++) {
//TODO: Align one of the pointers. destination is more likely to be aligned
*(uint*)pd = *(uint*)ps;
pd += 4;
ps += 4;
}
for (int i = 0; i < length; i++, ps++, pd++)
*pd = *ps;
}
public override void ReadBytes(uint offset, byte[] destination, int destinationIndex, int length) =>
Marshal.Copy((IntPtr)(data + offset), destination, destinationIndex, length);
public override byte ReadByte(uint offset) => *(data + offset);
public override ushort ReadUInt16(uint offset) => *(ushort*)(data + offset);
public override uint ReadUInt32(uint offset) => *(uint*)(data + offset);
public override ulong ReadUInt64(uint offset) => *(ulong*)(data + offset);
public override float ReadSingle(uint offset) => *(float*)(data + offset);
public override double ReadDouble(uint offset) => *(double*)(data + offset);
public override Guid ReadGuid(uint offset) => *(Guid*)(data + offset);
public override string ReadUtf16String(uint offset, int chars) => new string((char*)(data + offset), 0, chars);
public override string ReadString(uint offset, int length, Encoding encoding) => new string((sbyte*)(data + offset), 0, length, encoding);
public override bool TryGetOffsetOf(uint offset, uint endOffset, byte value, out uint valueOffset) {
var pd = data;
// If this code gets updated, also update the other DataStream implementations
byte* p = pd + offset;
uint count = (endOffset - offset) / 4;
for (uint i = 0; i < count; i++) {
if (*p == value) {
valueOffset = (uint)(p - pd);
return true;
}
p++;
if (*p == value) {
valueOffset = (uint)(p - pd);
return true;
}
p++;
if (*p == value) {
valueOffset = (uint)(p - pd);
return true;
}
p++;
if (*p == value) {
valueOffset = (uint)(p - pd);
return true;
}
p++;
}
byte* pe = pd + endOffset;
while (p != pe) {
if (*p == value) {
valueOffset = (uint)(p - pd);
return true;
}
p++;
}
valueOffset = 0;
return false;
}
}
}