RyuKen/Ryujinx.HLE/Utilities/StringUtils.cs
Mary 51fa1b2cb0
hle: Improve safety (#2778)
* timezone: Make timezone implementation safe

* hle: Do not use TrimEnd to parse ASCII strings

This adds an util that handle reading an ASCII string in a safe way.
Previously it was possible to read malformed data that could cause
various undefined behaviours in multiple services.

* hid: Remove an useless unsafe modifier on keyboard update

* Address gdkchan's comment

* Address gdkchan's comment
2021-10-24 19:13:20 -03:00

145 lines
No EOL
4 KiB
C#

using LibHac.Common;
using Ryujinx.HLE.HOS;
using System;
using System.Globalization;
using System.IO;
using System.Linq;
using System.Text;
namespace Ryujinx.HLE.Utilities
{
static class StringUtils
{
public static byte[] GetFixedLengthBytes(string inputString, int size, Encoding encoding)
{
inputString += "\0";
int bytesCount = encoding.GetByteCount(inputString);
byte[] output = new byte[size];
if (bytesCount < size)
{
encoding.GetBytes(inputString, 0, inputString.Length, output, 0);
}
else
{
int nullSize = encoding.GetByteCount("\0");
output = encoding.GetBytes(inputString);
Array.Resize(ref output, size - nullSize);
output = output.Concat(encoding.GetBytes("\0")).ToArray();
}
return output;
}
public static string ReadInlinedAsciiString(BinaryReader reader, int maxSize)
{
byte[] data = reader.ReadBytes(maxSize);
int stringSize = Array.IndexOf<byte>(data, 0);
return Encoding.ASCII.GetString(data, 0, stringSize < 0 ? maxSize : stringSize);
}
public static byte[] HexToBytes(string hexString)
{
// Ignore last character if HexLength % 2 != 0.
int bytesInHex = hexString.Length / 2;
byte[] output = new byte[bytesInHex];
for (int index = 0; index < bytesInHex; index++)
{
output[index] = byte.Parse(hexString.Substring(index * 2, 2), NumberStyles.HexNumber);
}
return output;
}
public static string ReadUtf8String(ServiceCtx context, int index = 0)
{
ulong position = context.Request.PtrBuff[index].Position;
ulong size = context.Request.PtrBuff[index].Size;
using (MemoryStream ms = new MemoryStream())
{
while (size-- > 0)
{
byte value = context.Memory.Read<byte>(position++);
if (value == 0)
{
break;
}
ms.WriteByte(value);
}
return Encoding.UTF8.GetString(ms.ToArray());
}
}
public static U8Span ReadUtf8Span(ServiceCtx context, int index = 0)
{
ulong position = context.Request.PtrBuff[index].Position;
ulong size = context.Request.PtrBuff[index].Size;
ReadOnlySpan<byte> buffer = context.Memory.GetSpan(position, (int)size);
return new U8Span(buffer);
}
public static string ReadUtf8StringSend(ServiceCtx context, int index = 0)
{
ulong position = context.Request.SendBuff[index].Position;
ulong size = context.Request.SendBuff[index].Size;
using (MemoryStream ms = new MemoryStream())
{
while (size-- > 0)
{
byte value = context.Memory.Read<byte>(position++);
if (value == 0)
{
break;
}
ms.WriteByte(value);
}
return Encoding.UTF8.GetString(ms.ToArray());
}
}
public static int CompareCStr(ReadOnlySpan<char> s1, ReadOnlySpan<char> s2)
{
int s1Index = 0;
int s2Index = 0;
while (s1[s1Index] != 0 && s2[s2Index] != 0 && s1[s1Index] == s2[s2Index])
{
s1Index += 1;
s2Index += 1;
}
return s2[s2Index] - s1[s1Index];
}
public static int LengthCstr(ReadOnlySpan<char> s)
{
int i = 0;
while (s[i] != '\0')
{
i++;
}
return i;
}
}
}