GetCharCount() [2/5]

unsafe override int System.Text.UnicodeEncoding.GetCharCount ( byte * bytes, int count, DecoderNLS baseDecoder )

inlinesealedpackagevirtual

Reimplemented from System.Text.Encoding.

Definition at line 698 of file UnicodeEncoding.cs.

    {
        Decoder decoder = (Decoder)baseDecoder;
        byte* ptr = bytes + count;
        byte* byteStart = bytes;
        int num = -1;
        char c = '\0';
        int num2 = count >> 1;
        DecoderFallbackBuffer decoderFallbackBuffer = null;
        if (decoder != null)
        {
            num = decoder.lastByte;
            c = decoder.lastChar;
            if (c > '\0')
            {
                num2++;
            }
            if (num >= 0 && (count & 1) == 1)
            {
                num2++;
            }
        }
        while (bytes < ptr)
        {
            if ((bigEndian ^ BitConverter.IsLittleEndian) && ((ulong)bytes & 7uL) == 0L && num == -1 && c == '\0')
            {
                ulong* ptr2 = (ulong*)(ptr - 7);
                ulong* ptr3;
                for (ptr3 = (ulong*)bytes; ptr3 < ptr2; ptr3++)
                {
                    if ((0x8000800080008000uL & *ptr3) == 0L)
                    {
                        continue;
                    }
                    ulong num3 = (0xF800F800F800F800uL & *ptr3) ^ 0xD800D800D800D800uL;
                    if ((num3 & 0xFFFF000000000000uL) == 0L || (num3 & 0xFFFF00000000L) == 0L || (num3 & 0xFFFF0000u) == 0L || (num3 & 0xFFFF) == 0L)
                    {
                        long num4 = -287953294993589248L & (long)(*ptr3);
                        if (!BitConverter.IsLittleEndian)
                        {
                        }
                        if (num4 != -2593835887162763264L)
                        {
                            break;
                        }
                    }
                }
                bytes = (byte*)ptr3;
                if (bytes >= ptr)
                {
                    break;
                }
            }
            if (num < 0)
            {
                num = *(bytes++);
                if (bytes >= ptr)
                {
                    break;
                }
            }
            char c2 = ((!bigEndian) ? ((char)((*(bytes++) << 8) | num)) : ((char)((num << 8) | *(bytes++))));
            num = -1;
            if (c2 >= '\ud800' && c2 <= '\udfff')
            {
                if (c2 <= '\udbff')
                {
                    if (c > '\0')
                    {
                        num2--;
                        byte[] array = null;
                        array = ((!bigEndian) ? new byte[2]
                        {
                            (byte)c,
                            (byte)((int)c >> 8)
                        } : new byte[2]
                        {
                            (byte)((int)c >> 8),
                            (byte)c
                        });
                        if (decoderFallbackBuffer == null)
                        {
                            decoderFallbackBuffer = ((decoder != null) ? decoder.FallbackBuffer : decoderFallback.CreateFallbackBuffer());
                            decoderFallbackBuffer.InternalInitialize(byteStart, null);
                        }
                        num2 += decoderFallbackBuffer.InternalFallback(array, bytes);
                    }
                    c = c2;
                }
                else if (c == '\0')
                {
                    num2--;
                    byte[] array2 = null;
                    array2 = ((!bigEndian) ? new byte[2]
                    {
                        (byte)c2,
                        (byte)((int)c2 >> 8)
                    } : new byte[2]
                    {
                        (byte)((int)c2 >> 8),
                        (byte)c2
                    });
                    if (decoderFallbackBuffer == null)
                    {
                        decoderFallbackBuffer = ((decoder != null) ? decoder.FallbackBuffer : decoderFallback.CreateFallbackBuffer());
                        decoderFallbackBuffer.InternalInitialize(byteStart, null);
                    }
                    num2 += decoderFallbackBuffer.InternalFallback(array2, bytes);
                }
                else
                {
                    c = '\0';
                }
            }
            else if (c > '\0')
            {
                num2--;
                byte[] array3 = null;
                array3 = ((!bigEndian) ? new byte[2]
                {
                    (byte)c,
                    (byte)((int)c >> 8)
                } : new byte[2]
                {
                    (byte)((int)c >> 8),
                    (byte)c
                });
                if (decoderFallbackBuffer == null)
                {
                    decoderFallbackBuffer = ((decoder != null) ? decoder.FallbackBuffer : decoderFallback.CreateFallbackBuffer());
                    decoderFallbackBuffer.InternalInitialize(byteStart, null);
                }
                num2 += decoderFallbackBuffer.InternalFallback(array3, bytes);
                c = '\0';
            }
        }
        if (decoder == null || decoder.MustFlush)
        {
            if (c > '\0')
            {
                num2--;
                byte[] array4 = null;
                array4 = ((!bigEndian) ? new byte[2]
                {
                    (byte)c,
                    (byte)((int)c >> 8)
                } : new byte[2]
                {
                    (byte)((int)c >> 8),
                    (byte)c
                });
                if (decoderFallbackBuffer == null)
                {
                    decoderFallbackBuffer = ((decoder != null) ? decoder.FallbackBuffer : decoderFallback.CreateFallbackBuffer());
                    decoderFallbackBuffer.InternalInitialize(byteStart, null);
                }
                num2 += decoderFallbackBuffer.InternalFallback(array4, bytes);
                c = '\0';
            }
            if (num >= 0)
            {
                if (decoderFallbackBuffer == null)
                {
                    decoderFallbackBuffer = ((decoder != null) ? decoder.FallbackBuffer : decoderFallback.CreateFallbackBuffer());
                    decoderFallbackBuffer.InternalInitialize(byteStart, null);
                }
                num2 += decoderFallbackBuffer.InternalFallback(new byte[1] { (byte)num }, bytes);
                num = -1;
            }
        }
        if (c > '\0')
        {
            num2--;
        }
        return num2;
    }

References System.array, System.Text.UnicodeEncoding.bigEndian, System.bytes, System.count, System.Text.DecoderFallback.CreateFallbackBuffer(), System.Text.Encoding.decoderFallback, System.Text.DecoderNLS.FallbackBuffer, System.Text.DecoderFallbackBuffer.InternalFallback(), System.Text.DecoderFallbackBuffer.InternalInitialize(), System.BitConverter.IsLittleEndian, System.L, System.Text.UnicodeEncoding.Decoder.lastByte, System.Text.UnicodeEncoding.Decoder.lastChar, and System.Text.DecoderNLS.MustFlush.