GetByteCount() [2/7]

unsafe override int System.Text.UnicodeEncoding.GetByteCount ( char * chars, int count, EncoderNLS encoder )

inlinesealedpackagevirtual

Reimplemented from System.Text.Encoding.

Definition at line 343 of file UnicodeEncoding.cs.

    {
        int num = count << 1;
        if (num < 0)
        {
            throw new ArgumentOutOfRangeException("count", SR.ArgumentOutOfRange_GetByteCountOverflow);
        }
        char* charStart = chars;
        char* ptr = chars + count;
        char c = '\0';
        bool flag = false;
        EncoderFallbackBuffer encoderFallbackBuffer = null;
        if (encoder != null)
        {
            c = encoder._charLeftOver;
            if (c > '\0')
            {
                num += 2;
            }
            if (encoder.InternalHasFallbackBuffer)
            {
                encoderFallbackBuffer = encoder.FallbackBuffer;
                if (encoderFallbackBuffer.Remaining > 0)
                {
                    throw new ArgumentException(SR.Format(SR.Argument_EncoderFallbackNotEmpty, EncodingName, encoder.Fallback?.GetType()));
                }
                encoderFallbackBuffer.InternalInitialize(charStart, ptr, encoder, setEncoder: false);
            }
        }
        while (true)
        {
            char num2 = encoderFallbackBuffer?.InternalGetNextChar() ?? '\0';
            char c2 = num2;
            char* chars2;
            if (num2 != 0 || chars < ptr)
            {
                if (c2 == '\0')
                {
                    if ((bigEndian ^ BitConverter.IsLittleEndian) && ((ulong)chars & 7uL) == 0L && c == '\0')
                    {
                        ulong* ptr2 = (ulong*)(ptr - 3);
                        ulong* ptr3;
                        for (ptr3 = (ulong*)chars; 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;
                                }
                            }
                        }
                        chars = (char*)ptr3;
                        if (chars >= ptr)
                        {
                            goto IL_0295;
                        }
                    }
                    c2 = *chars;
                    chars++;
                }
                else
                {
                    num += 2;
                }
                if (c2 >= '\ud800' && c2 <= '\udfff')
                {
                    if (c2 <= '\udbff')
                    {
                        if (c > '\0')
                        {
                            chars--;
                            num -= 2;
                            if (encoderFallbackBuffer == null)
                            {
                                encoderFallbackBuffer = ((encoder != null) ? encoder.FallbackBuffer : encoderFallback.CreateFallbackBuffer());
                                encoderFallbackBuffer.InternalInitialize(charStart, ptr, encoder, setEncoder: false);
                            }
                            chars2 = chars;
                            encoderFallbackBuffer.InternalFallback(c, ref chars2);
                            chars = chars2;
                            c = '\0';
                        }
                        else
                        {
                            c = c2;
                        }
                    }
                    else if (c == '\0')
                    {
                        num -= 2;
                        if (encoderFallbackBuffer == null)
                        {
                            encoderFallbackBuffer = ((encoder != null) ? encoder.FallbackBuffer : encoderFallback.CreateFallbackBuffer());
                            encoderFallbackBuffer.InternalInitialize(charStart, ptr, encoder, setEncoder: false);
                        }
                        chars2 = chars;
                        encoderFallbackBuffer.InternalFallback(c2, ref chars2);
                        chars = chars2;
                    }
                    else
                    {
                        c = '\0';
                    }
                }
                else if (c > '\0')
                {
                    chars--;
                    if (encoderFallbackBuffer == null)
                    {
                        encoderFallbackBuffer = ((encoder != null) ? encoder.FallbackBuffer : encoderFallback.CreateFallbackBuffer());
                        encoderFallbackBuffer.InternalInitialize(charStart, ptr, encoder, setEncoder: false);
                    }
                    chars2 = chars;
                    encoderFallbackBuffer.InternalFallback(c, ref chars2);
                    chars = chars2;
                    num -= 2;
                    c = '\0';
                }
                continue;
            }
            goto IL_0295;
            IL_0295:
            if (c <= '\0')
            {
                break;
            }
            num -= 2;
            if (encoder != null && !encoder.MustFlush)
            {
                break;
            }
            if (flag)
            {
                throw new ArgumentException(SR.Format(SR.Argument_RecursiveFallback, c), "chars");
            }
            if (encoderFallbackBuffer == null)
            {
                encoderFallbackBuffer = ((encoder != null) ? encoder.FallbackBuffer : encoderFallback.CreateFallbackBuffer());
                encoderFallbackBuffer.InternalInitialize(charStart, ptr, encoder, setEncoder: false);
            }
            chars2 = chars;
            encoderFallbackBuffer.InternalFallback(c, ref chars2);
            chars = chars2;
            c = '\0';
            flag = true;
        }
        return num;
    }

References System.Text.EncoderNLS._charLeftOver, System.SR.Argument_EncoderFallbackNotEmpty, System.SR.Argument_RecursiveFallback, System.SR.ArgumentOutOfRange_GetByteCountOverflow, System.Text.UnicodeEncoding.bigEndian, System.chars, System.count, System.Text.EncoderFallback.CreateFallbackBuffer(), System.Text.Encoding.encoderFallback, System.Text.Encoding.EncodingName, System.Text.EncoderNLS.Fallback, System.Text.EncoderNLS.FallbackBuffer, System.SR.Format(), System.Text.EncoderFallbackBuffer.InternalFallback(), System.Text.EncoderFallbackBuffer.InternalGetNextChar(), System.Text.EncoderNLS.InternalHasFallbackBuffer, System.Text.EncoderFallbackBuffer.InternalInitialize(), System.BitConverter.IsLittleEndian, System.L, System.Text.EncoderNLS.MustFlush, and System.Text.EncoderFallbackBuffer.Remaining.