using Microsoft.Win32.SafeHandles; using System.Buffers.Binary; using System.IO; using System.Runtime.InteropServices; using System.Runtime.Serialization; namespace System.Text { internal abstract class BaseCodePageEncoding : EncodingNLS, ISerializable { [StructLayout(LayoutKind.Explicit)] internal struct CodePageDataFileHeader { [FieldOffset(0)] internal char TableName; [FieldOffset(32)] internal ushort Version; [FieldOffset(40)] internal short CodePageCount; [FieldOffset(42)] internal short unused1; } [StructLayout(LayoutKind.Explicit, Pack = 2)] internal struct CodePageIndex { [FieldOffset(0)] internal char CodePageName; [FieldOffset(32)] internal short CodePage; [FieldOffset(34)] internal short ByteCount; [FieldOffset(36)] internal int Offset; } [StructLayout(LayoutKind.Explicit)] internal struct CodePageHeader { [FieldOffset(0)] internal char CodePageName; [FieldOffset(32)] internal ushort VersionMajor; [FieldOffset(34)] internal ushort VersionMinor; [FieldOffset(36)] internal ushort VersionRevision; [FieldOffset(38)] internal ushort VersionBuild; [FieldOffset(40)] internal short CodePage; [FieldOffset(42)] internal short ByteCount; [FieldOffset(44)] internal char UnicodeReplace; [FieldOffset(46)] internal ushort ByteReplace; } protected int dataTableCodePage; protected int iExtraBytes; protected char[] arrayUnicodeBestFit; protected char[] arrayBytesBestFit; private static readonly byte[] s_codePagesDataHeader = new byte[44]; protected static Stream s_codePagesEncodingDataStream = GetEncodingDataStream("codepages.nlp"); protected static readonly object s_streamLock = new object(); protected byte[] m_codePageHeader = new byte[48]; protected int m_firstDataWordOffset; protected int m_dataSize; protected SafeAllocHHandle safeNativeMemoryHandle; internal BaseCodePageEncoding(int codepage, int dataCodePage) : base(codepage, new InternalEncoderBestFitFallback(null), new InternalDecoderBestFitFallback(null)) { ((InternalEncoderBestFitFallback)base.EncoderFallback).encoding = this; ((InternalDecoderBestFitFallback)base.DecoderFallback).encoding = this; dataTableCodePage = dataCodePage; LoadCodePageTables(); } internal BaseCodePageEncoding(int codepage, int dataCodePage, EncoderFallback enc, DecoderFallback dec) : base(codepage, enc, dec) { dataTableCodePage = dataCodePage; LoadCodePageTables(); } void ISerializable.GetObjectData(SerializationInfo info, StreamingContext context) { throw new PlatformNotSupportedException(); } private unsafe static void ReadCodePageDataFileHeader(Stream stream, byte[] codePageDataFileHeader) { stream.Read(codePageDataFileHeader, 0, codePageDataFileHeader.Length); if (!BitConverter.IsLittleEndian) { fixed (byte* ptr = &codePageDataFileHeader[0]) { CodePageDataFileHeader* ptr2 = (CodePageDataFileHeader*)ptr; char* ptr3 = &ptr2->TableName; for (int i = 0; i < 16; i++) { ptr3[i] = (char)BinaryPrimitives.ReverseEndianness(ptr3[i]); } ushort* ptr4 = &ptr2->Version; for (int j = 0; j < 4; j++) { ptr4[j] = BinaryPrimitives.ReverseEndianness(ptr4[j]); } ptr2->CodePageCount = BinaryPrimitives.ReverseEndianness(ptr2->CodePageCount); } } } private unsafe static void ReadCodePageIndex(Stream stream, byte[] codePageIndex) { stream.Read(codePageIndex, 0, codePageIndex.Length); if (!BitConverter.IsLittleEndian) { fixed (byte* ptr = &codePageIndex[0]) { CodePageIndex* ptr2 = (CodePageIndex*)ptr; char* ptr3 = &ptr2->CodePageName; for (int i = 0; i < 16; i++) { ptr3[i] = (char)BinaryPrimitives.ReverseEndianness(ptr3[i]); } ptr2->CodePage = BinaryPrimitives.ReverseEndianness(ptr2->CodePage); ptr2->ByteCount = BinaryPrimitives.ReverseEndianness(ptr2->ByteCount); ptr2->Offset = BinaryPrimitives.ReverseEndianness(ptr2->Offset); } } } private unsafe static void ReadCodePageHeader(Stream stream, byte[] codePageHeader) { stream.Read(codePageHeader, 0, codePageHeader.Length); if (!BitConverter.IsLittleEndian) { fixed (byte* ptr = &codePageHeader[0]) { CodePageHeader* ptr2 = (CodePageHeader*)ptr; char* ptr3 = &ptr2->CodePageName; for (int i = 0; i < 16; i++) { ptr3[i] = (char)BinaryPrimitives.ReverseEndianness(ptr3[i]); } ptr2->VersionMajor = BinaryPrimitives.ReverseEndianness(ptr2->VersionMajor); ptr2->VersionMinor = BinaryPrimitives.ReverseEndianness(ptr2->VersionMinor); ptr2->VersionRevision = BinaryPrimitives.ReverseEndianness(ptr2->VersionRevision); ptr2->VersionBuild = BinaryPrimitives.ReverseEndianness(ptr2->VersionBuild); ptr2->CodePage = BinaryPrimitives.ReverseEndianness(ptr2->CodePage); ptr2->ByteCount = BinaryPrimitives.ReverseEndianness(ptr2->ByteCount); ptr2->UnicodeReplace = (char)BinaryPrimitives.ReverseEndianness(ptr2->UnicodeReplace); ptr2->ByteReplace = BinaryPrimitives.ReverseEndianness(ptr2->ByteReplace); } } } internal static Stream GetEncodingDataStream(string tableName) { Stream manifestResourceStream = typeof(CodePagesEncodingProvider).Assembly.GetManifestResourceStream(tableName); if (manifestResourceStream == null) throw new InvalidOperationException(); ReadCodePageDataFileHeader(manifestResourceStream, s_codePagesDataHeader); return manifestResourceStream; } private void LoadCodePageTables() { if (!FindCodePage(dataTableCodePage)) throw new NotSupportedException(System.SR.Format(System.SR.NotSupported_NoCodepageData, CodePage)); LoadManagedCodePage(); } private unsafe bool FindCodePage(int codePage) { byte[] array = new byte[sizeof(CodePageIndex)]; lock (s_streamLock) { s_codePagesEncodingDataStream.Seek(44, SeekOrigin.Begin); int codePageCount; fixed (byte* ptr = &s_codePagesDataHeader[0]) { CodePageDataFileHeader* ptr2 = (CodePageDataFileHeader*)ptr; codePageCount = ptr2->CodePageCount; } fixed (byte* ptr = &array[0]) { CodePageIndex* ptr3 = (CodePageIndex*)ptr; for (int i = 0; i < codePageCount; i++) { ReadCodePageIndex(s_codePagesEncodingDataStream, array); if (ptr3->CodePage == codePage) { long position = s_codePagesEncodingDataStream.Position; s_codePagesEncodingDataStream.Seek(ptr3->Offset, SeekOrigin.Begin); ReadCodePageHeader(s_codePagesEncodingDataStream, m_codePageHeader); m_firstDataWordOffset = (int)s_codePagesEncodingDataStream.Position; if (i == codePageCount - 1) m_dataSize = (int)(s_codePagesEncodingDataStream.Length - ptr3->Offset - m_codePageHeader.Length); else { s_codePagesEncodingDataStream.Seek(position, SeekOrigin.Begin); int offset = ptr3->Offset; ReadCodePageIndex(s_codePagesEncodingDataStream, array); m_dataSize = ptr3->Offset - offset - m_codePageHeader.Length; } return true; } } ptr = null; } } return false; } internal unsafe static int GetCodePageByteSize(int codePage) { byte[] array = new byte[sizeof(CodePageIndex)]; lock (s_streamLock) { s_codePagesEncodingDataStream.Seek(44, SeekOrigin.Begin); int codePageCount; fixed (byte* ptr = &s_codePagesDataHeader[0]) { CodePageDataFileHeader* ptr2 = (CodePageDataFileHeader*)ptr; codePageCount = ptr2->CodePageCount; } fixed (byte* ptr = &array[0]) { CodePageIndex* ptr3 = (CodePageIndex*)ptr; for (int i = 0; i < codePageCount; i++) { ReadCodePageIndex(s_codePagesEncodingDataStream, array); if (ptr3->CodePage == codePage) return ptr3->ByteCount; } ptr = null; } } return 0; } protected abstract void LoadManagedCodePage(); protected unsafe byte* GetNativeMemory(int iSize) { if (safeNativeMemoryHandle == null) { byte* handle = (byte*)(long)Marshal.AllocHGlobal(iSize); safeNativeMemoryHandle = new SafeAllocHHandle((IntPtr)handle); } return (byte*)(long)safeNativeMemoryHandle.DangerousGetHandle(); } protected abstract void ReadBestFitTable(); internal char[] GetBestFitUnicodeToBytesData() { if (arrayUnicodeBestFit == null) ReadBestFitTable(); return arrayUnicodeBestFit; } internal char[] GetBestFitBytesToUnicodeData() { if (arrayBytesBestFit == null) ReadBestFitTable(); return arrayBytesBestFit; } internal void CheckMemorySection() { if (safeNativeMemoryHandle != null && safeNativeMemoryHandle.DangerousGetHandle() == IntPtr.Zero) LoadManagedCodePage(); } private unsafe static void ReadCodePageIndex(Stream stream, Span<byte> codePageIndex) { stream.Read(codePageIndex); if (!BitConverter.IsLittleEndian) { fixed (byte* ptr = &codePageIndex[0]) { CodePageIndex* ptr2 = (CodePageIndex*)ptr; char* ptr3 = &ptr2->CodePageName; for (int i = 0; i < 16; i++) { ptr3[i] = (char)BinaryPrimitives.ReverseEndianness(ptr3[i]); } ptr2->CodePage = BinaryPrimitives.ReverseEndianness(ptr2->CodePage); ptr2->ByteCount = BinaryPrimitives.ReverseEndianness(ptr2->ByteCount); ptr2->Offset = BinaryPrimitives.ReverseEndianness(ptr2->Offset); } } } internal unsafe static EncodingInfo[] GetEncodings(CodePagesEncodingProvider provider) { lock (s_streamLock) { s_codePagesEncodingDataStream.Seek(44, SeekOrigin.Begin); int codePageCount; fixed (byte* ptr = &s_codePagesDataHeader[0]) { CodePageDataFileHeader* ptr2 = (CodePageDataFileHeader*)ptr; codePageCount = ptr2->CodePageCount; } EncodingInfo[] array = new EncodingInfo[codePageCount]; CodePageIndex codePageIndex = default(CodePageIndex); Span<byte> codePageIndex2 = new Span<byte>(&codePageIndex, sizeof(CodePageIndex)); for (int i = 0; i < codePageCount; i++) { ReadCodePageIndex(s_codePagesEncodingDataStream, codePageIndex2); string text; switch (codePageIndex.CodePage) { case 950: text = "big5"; break; case 10002: text = "x-mac-chinesetrad"; break; case 20833: text = "x-ebcdic-koreanextended"; break; default: text = new string(&codePageIndex.CodePageName); break; } string text2 = null; if (!System.SR.UsingResourceKeys()) text2 = EncodingNLS.GetLocalizedEncodingNameResource(codePageIndex.CodePage); array[i] = new EncodingInfo(provider, codePageIndex.CodePage, text, text2 ?? text); } return array; } } } }