mirror of
https://github.com/Ryujinx/Ryujinx.git
synced 2024-09-11 18:28:50 +02:00
78 lines
No EOL
1.9 KiB
C#
78 lines
No EOL
1.9 KiB
C#
using System;
|
|
|
|
namespace Ryujinx.HLE.Loaders.Compression
|
|
{
|
|
static class Lz4
|
|
{
|
|
public static byte[] Decompress(byte[] Cmp, int DecLength)
|
|
{
|
|
byte[] Dec = new byte[DecLength];
|
|
|
|
int CmpPos = 0;
|
|
int DecPos = 0;
|
|
|
|
int GetLength(int Length)
|
|
{
|
|
byte Sum;
|
|
|
|
if (Length == 0xf)
|
|
{
|
|
do
|
|
{
|
|
Length += (Sum = Cmp[CmpPos++]);
|
|
}
|
|
while (Sum == 0xff);
|
|
}
|
|
|
|
return Length;
|
|
}
|
|
|
|
do
|
|
{
|
|
byte Token = Cmp[CmpPos++];
|
|
|
|
int EncCount = (Token >> 0) & 0xf;
|
|
int LitCount = (Token >> 4) & 0xf;
|
|
|
|
//Copy literal chunck
|
|
LitCount = GetLength(LitCount);
|
|
|
|
Buffer.BlockCopy(Cmp, CmpPos, Dec, DecPos, LitCount);
|
|
|
|
CmpPos += LitCount;
|
|
DecPos += LitCount;
|
|
|
|
if (CmpPos >= Cmp.Length)
|
|
{
|
|
break;
|
|
}
|
|
|
|
//Copy compressed chunck
|
|
int Back = Cmp[CmpPos++] << 0 |
|
|
Cmp[CmpPos++] << 8;
|
|
|
|
EncCount = GetLength(EncCount) + 4;
|
|
|
|
int EncPos = DecPos - Back;
|
|
|
|
if (EncCount <= Back)
|
|
{
|
|
Buffer.BlockCopy(Dec, EncPos, Dec, DecPos, EncCount);
|
|
|
|
DecPos += EncCount;
|
|
}
|
|
else
|
|
{
|
|
while (EncCount-- > 0)
|
|
{
|
|
Dec[DecPos++] = Dec[EncPos++];
|
|
}
|
|
}
|
|
}
|
|
while (CmpPos < Cmp.Length &&
|
|
DecPos < Dec.Length);
|
|
|
|
return Dec;
|
|
}
|
|
}
|
|
} |