/// <summary>
/// Decodes the specified input into the output buffer.
/// </summary>
/// <remarks>
/// <para>Decodes the specified input into the output buffer.</para>
/// <para>The output buffer should be large enough to hold all of the
/// decoded input. For estimating the size needed for the output buffer,
/// see <see cref="EstimateOutputLength"/>.</para>
/// </remarks>
/// <returns>The number of bytes written to the output buffer.</returns>
/// <param name="input">A pointer to the beginning of the input buffer.</param>
/// <param name="length">The length of the input buffer.</param>
/// <param name="output">A pointer to the beginning of the output buffer.</param>
public unsafe int Decode(byte *input, int length, byte *output)
{
byte *inend = input + length;
byte *outptr = output;
byte *inptr = input;
byte c;
while (inptr < inend)
{
switch (state)
{
case HexDecoderState.PassThrough:
while (inptr < inend)
{
c = *inptr++;
if (c == '%')
{
state = HexDecoderState.Percent;
break;
}
*outptr++ = c;
}
break;
case HexDecoderState.Percent:
c = *inptr++;
state = HexDecoderState.DecodeByte;
saved = c;
break;
case HexDecoderState.DecodeByte:
c = *inptr++;
if (c.IsXDigit() && saved.IsXDigit())
{
saved = saved.ToXDigit();
c = c.ToXDigit();
*outptr++ = (byte)((saved << 4) | c);
}
else
{
// invalid encoded sequence - pass it through undecoded
*outptr++ = (byte)'%';
*outptr++ = saved;
*outptr++ = c;
}
state = HexDecoderState.PassThrough;
break;
}
}
return((int)(outptr - output));
}
/// <summary>
/// Resets the decoder.
/// </summary>
/// <remarks>
/// Resets the state of the decoder.
/// </remarks>
public void Reset()
{
state = HexDecoderState.PassThrough;
saved = 0;
}
/// <summary>
/// Resets the decoder.
/// </summary>
/// <remarks>
/// Resets the state of the decoder.
/// </remarks>
public void Reset ()
{
state = HexDecoderState.PassThrough;
saved = 0;
}
/// <summary>
/// Decodes the specified input into the output buffer.
/// </summary>
/// <remarks>
/// <para>Decodes the specified input into the output buffer.</para>
/// <para>The output buffer should be large enough to hold all of the
/// decoded input. For estimating the size needed for the output buffer,
/// see <see cref="EstimateOutputLength"/>.</para>
/// </remarks>
/// <returns>The number of bytes written to the output buffer.</returns>
/// <param name="input">A pointer to the beginning of the input buffer.</param>
/// <param name="length">The length of the input buffer.</param>
/// <param name="output">A pointer to the beginning of the output buffer.</param>
public unsafe int Decode (byte* input, int length, byte* output)
{
byte* inend = input + length;
byte* outptr = output;
byte* inptr = input;
byte c;
while (inptr < inend) {
switch (state) {
case HexDecoderState.PassThrough:
while (inptr < inend) {
c = *inptr++;
if (c == '%') {
state = HexDecoderState.Percent;
break;
}
*outptr++ = c;
}
break;
case HexDecoderState.Percent:
c = *inptr++;
state = HexDecoderState.DecodeByte;
saved = c;
break;
case HexDecoderState.DecodeByte:
c = *inptr++;
if (c.IsXDigit () && saved.IsXDigit ()) {
saved = saved.ToXDigit ();
c = c.ToXDigit ();
*outptr++ = (byte) ((saved << 4) | c);
} else {
// invalid encoded sequence - pass it through undecoded
*outptr++ = (byte) '%';
*outptr++ = saved;
*outptr++ = c;
}
state = HexDecoderState.PassThrough;
break;
}
}
return (int) (outptr - output);
}
