public IpsPatcher(BinaryReader reader)
{
_patches = ParseIps(reader);
if (_patches != null)
{
Logger.Info?.Print(LogClass.ModLoader, "IPS patch loaded successfully");
}
}
/// <summary>
/// Adds all patches from an existing MemPatch
/// </summary>
/// <param name="patches">The patches to add</param>
public void AddFrom(MemPatch patches)
{
if (patches == null)
{
return;
}
foreach (var(patchOffset, patch) in patches._patches)
{
_patches[patchOffset] = patch;
}
}
private MemPatch Parse()
{
if (_reader == null)
{
return(null);
}
MemPatch patches = new MemPatch();
bool enabled = false;
bool printValues = false;
int offset_shift = 0;
string line;
int lineNum = 0;
private static MemPatch ParseIps(BinaryReader reader)
{
Span <byte> IpsHeaderMagic = Encoding.ASCII.GetBytes("PATCH").AsSpan();
Span <byte> IpsTailMagic = Encoding.ASCII.GetBytes("EOF").AsSpan();
Span <byte> Ips32HeaderMagic = Encoding.ASCII.GetBytes("IPS32").AsSpan();
Span <byte> Ips32TailMagic = Encoding.ASCII.GetBytes("EEOF").AsSpan();
MemPatch patches = new MemPatch();
var header = reader.ReadBytes(IpsHeaderMagic.Length).AsSpan();
if (header.Length != IpsHeaderMagic.Length)
{
return(null);
}
bool is32;
Span <byte> tailSpan;
if (header.SequenceEqual(IpsHeaderMagic))
{
is32 = false;
tailSpan = IpsTailMagic;
}
else if (header.SequenceEqual(Ips32HeaderMagic))
{
is32 = true;
tailSpan = Ips32TailMagic;
}
else
{
return(null);
}
byte[] buf = new byte[tailSpan.Length];
bool ReadNext(int size) => reader.Read(buf, 0, size) != size;
while (true)
{
if (ReadNext(buf.Length))
{
return(null);
}
if (buf.AsSpan().SequenceEqual(tailSpan))
{
break;
}
int patchOffset = is32 ? buf[0] << 24 | buf[1] << 16 | buf[2] << 8 | buf[3]
: buf[0] << 16 | buf[1] << 8 | buf[2];
if (ReadNext(2))
{
return(null);
}
int patchSize = buf[0] << 8 | buf[1];
if (patchSize == 0) // RLE/Fill mode
{
if (ReadNext(2))
{
return(null);
}
int fillLength = buf[0] << 8 | buf[1];
if (ReadNext(1))
{
return(null);
}
patches.AddFill((uint)patchOffset, fillLength, buf[0]);
}
else // Copy mode
{
var patch = reader.ReadBytes(patchSize);
if (patch.Length != patchSize)
{
return(null);
}
patches.Add((uint)patchOffset, patch);
}
}
return(patches);
}
public void AddPatches(MemPatch patches)
{
patches.AddFrom(_patches);
}