private void EncodeCore(ref Writer writer, char *input, uint charsRemaining)
{
while (charsRemaining != 0)
{
int nextScalar = UnicodeHelpers.GetScalarValueFromUtf16(input, endOfString: (charsRemaining == 1));
if (UnicodeHelpers.IsSupplementaryCodePoint(nextScalar))
{
// Supplementary characters should always be encoded numerically.
WriteEncodedScalar(ref writer, (uint)nextScalar);
// We consume two UTF-16 characters for a single supplementary character.
input += 2;
charsRemaining -= 2;
}
else
{
// Otherwise, this was a BMP character.
input++;
charsRemaining--;
char c = (char)nextScalar;
if (IsCharacterAllowed(c))
{
writer.Write(c);
}
else
{
WriteEncodedScalar(ref writer, (uint)nextScalar);
}
}
}
}
private unsafe void EncodeCore(TextWriter output, char *value, int valueLength)
{
Debug.Assert(value != null & output != null);
Debug.Assert(valueLength >= 0);
int bufferLength = MaxOutputCharactersPerInputCharacter;
char *buffer = stackalloc char[bufferLength];
char firstChar = *value;
char secondChar = firstChar;
bool wasSurrogatePair = false;
int charsWritten;
// this loop processes character pairs (in case they are surrogates).
// there is an if block below to process single last character.
for (int secondCharIndex = 1; secondCharIndex < valueLength; secondCharIndex++)
{
if (!wasSurrogatePair)
{
firstChar = secondChar;
}
else
{
firstChar = value[secondCharIndex - 1];
}
secondChar = value[secondCharIndex];
if (!WillEncode(firstChar))
{
wasSurrogatePair = false;
output.Write(firstChar);
}
else
{
int nextScalar = UnicodeHelpers.GetScalarValueFromUtf16(firstChar, secondChar, out wasSurrogatePair);
if (!TryEncodeUnicodeScalar(nextScalar, buffer, bufferLength, out charsWritten))
{
throw new ArgumentException("Argument encoder does not implement MaxOutputCharsPerInputChar correctly.");
}
Write(output, buffer, charsWritten);
if (wasSurrogatePair)
{
secondCharIndex++;
}
}
}
if (!wasSurrogatePair)
{
firstChar = value[valueLength - 1];
int nextScalar = UnicodeHelpers.GetScalarValueFromUtf16(firstChar, null, out wasSurrogatePair);
if (!TryEncodeUnicodeScalar(nextScalar, buffer, bufferLength, out charsWritten))
{
throw new ArgumentException("Argument encoder does not implement MaxOutputCharsPerInputChar correctly.");
}
Write(output, buffer, charsWritten);
}
}
private static unsafe void EncodeCore(this TextEncoder encoder, char *value, int charCount, TextWriter output)
{
int bufferLength = encoder.MaxOutputCharsPerInputChar;
char *buffer = stackalloc char[bufferLength];
char firstChar = *value;
char secondChar = firstChar;
bool wasSurrogatePair = false;
int charsWritten;
// this loop processes character pairs (in case they are surrogates).
// there is an if block below to process single last character.
for (int secondCharIndex = 1; secondCharIndex < charCount; secondCharIndex++)
{
if (!wasSurrogatePair)
{
firstChar = secondChar;
}
else
{
firstChar = value[secondCharIndex - 1];
}
secondChar = value[secondCharIndex];
if (!encoder.Encodes(firstChar))
{
wasSurrogatePair = false;
output.Write(firstChar);
}
else
{
int nextScalar = UnicodeHelpers.GetScalarValueFromUtf16(firstChar, secondChar, out wasSurrogatePair);
if (!encoder.TryEncodeUnicodeScalar(nextScalar, buffer, bufferLength, out charsWritten))
{
throw new ArgumentException("Argument encoder does not implement MaxOutputCharsPerInputChar correctly.");
}
output.Write(buffer, charsWritten);
if (wasSurrogatePair)
{
secondCharIndex++;
}
}
}
if (!wasSurrogatePair)
{
firstChar = value[charCount - 1];
int nextScalar = UnicodeHelpers.GetScalarValueFromUtf16(firstChar, null, out wasSurrogatePair);
if (!encoder.TryEncodeUnicodeScalar(nextScalar, buffer, bufferLength, out charsWritten))
{
throw new ArgumentException("Argument encoder does not implement MaxOutputCharsPerInputChar correctly.");
}
output.Write(buffer, charsWritten);
}
}
// NOTE: The order of the parameters to this method is a work around for https://github.com/dotnet/corefx/issues/4455
// and the underlying Mono bug: https://bugzilla.xamarin.com/show_bug.cgi?id=36052.
// If changing the signature of this method, ensure this issue isn't regressing on Mono.
private unsafe int EncodeIntoBuffer(char *buffer, int bufferLength, char *value, int valueLength, int firstCharacterToEncode)
{
int totalWritten = 0;
if (firstCharacterToEncode > 0)
{
Debug.Assert(firstCharacterToEncode <= valueLength);
Buffer.MemoryCopy(source: value,
destination: buffer,
destinationSizeInBytes: sizeof(char) * bufferLength,
sourceBytesToCopy: sizeof(char) * firstCharacterToEncode);
totalWritten += firstCharacterToEncode;
bufferLength -= firstCharacterToEncode;
buffer += firstCharacterToEncode;
}
int valueIndex = firstCharacterToEncode;
char firstChar = value[valueIndex];
char secondChar = firstChar;
bool wasSurrogatePair = false;
int charsWritten;
// this loop processes character pairs (in case they are surrogates).
// there is an if block below to process single last character.
int secondCharIndex;
for (secondCharIndex = valueIndex + 1; secondCharIndex < valueLength; secondCharIndex++)
{
if (!wasSurrogatePair)
{
firstChar = secondChar;
}
else
{
firstChar = value[secondCharIndex - 1];
}
secondChar = value[secondCharIndex];
if (!WillEncode(firstChar))
{
wasSurrogatePair = false;
*buffer = firstChar;
buffer++;
bufferLength--;
totalWritten++;
}
else
{
int nextScalar = UnicodeHelpers.GetScalarValueFromUtf16(firstChar, secondChar, out wasSurrogatePair);
if (!TryEncodeUnicodeScalar(nextScalar, buffer, bufferLength, out charsWritten))
{
throw new ArgumentException("Argument encoder does not implement MaxOutputCharsPerInputChar correctly.");
}
buffer += charsWritten;
bufferLength -= charsWritten;
totalWritten += charsWritten;
if (wasSurrogatePair)
{
secondCharIndex++;
}
}
}
if (secondCharIndex == valueLength)
{
firstChar = value[valueLength - 1];
int nextScalar = UnicodeHelpers.GetScalarValueFromUtf16(firstChar, null, out wasSurrogatePair);
if (!TryEncodeUnicodeScalar(nextScalar, buffer, bufferLength, out charsWritten))
{
throw new ArgumentException("Argument encoder does not implement MaxOutputCharsPerInputChar correctly.");
}
buffer += charsWritten;
bufferLength -= charsWritten;
totalWritten += charsWritten;
}
return(totalWritten);
}
private unsafe OperationStatus EncodeIntoBuffer(
char *buffer,
int bufferLength,
char *value,
int valueLength,
out int charsConsumed,
out int charsWritten,
int firstCharacterToEncode,
bool isFinalBlock = true)
{
Debug.Assert(value != null);
Debug.Assert(firstCharacterToEncode >= 0);
char *originalBuffer = buffer;
charsWritten = 0;
if (firstCharacterToEncode > 0)
{
Debug.Assert(firstCharacterToEncode <= valueLength);
Buffer.MemoryCopy(source: value,
destination: buffer,
destinationSizeInBytes: sizeof(char) * bufferLength,
sourceBytesToCopy: sizeof(char) * firstCharacterToEncode);
charsWritten += firstCharacterToEncode;
bufferLength -= firstCharacterToEncode;
buffer += firstCharacterToEncode;
}
int valueIndex = firstCharacterToEncode;
char firstChar = value[valueIndex];
char secondChar = firstChar;
bool wasSurrogatePair = false;
// this loop processes character pairs (in case they are surrogates).
// there is an if block below to process single last character.
int secondCharIndex;
for (secondCharIndex = valueIndex + 1; secondCharIndex < valueLength; secondCharIndex++)
{
if (!wasSurrogatePair)
{
firstChar = secondChar;
}
else
{
firstChar = value[secondCharIndex - 1];
}
secondChar = value[secondCharIndex];
if (!WillEncode(firstChar))
{
wasSurrogatePair = false;
*buffer = firstChar;
buffer++;
bufferLength--;
charsWritten++;
}
else
{
int nextScalar = UnicodeHelpers.GetScalarValueFromUtf16(firstChar, secondChar, out wasSurrogatePair, out bool _);
if (!TryEncodeUnicodeScalar(nextScalar, buffer, bufferLength, out int charsWrittenThisTime))
{
charsConsumed = (int)(originalBuffer - buffer);
return(OperationStatus.DestinationTooSmall);
}
if (wasSurrogatePair)
{
secondCharIndex++;
}
buffer += charsWrittenThisTime;
bufferLength -= charsWrittenThisTime;
charsWritten += charsWrittenThisTime;
}
}
if (secondCharIndex == valueLength)
{
firstChar = value[valueLength - 1];
int nextScalar = UnicodeHelpers.GetScalarValueFromUtf16(firstChar, null, out wasSurrogatePair, out bool needMoreData);
if (!isFinalBlock && needMoreData)
{
Debug.Assert(wasSurrogatePair == false);
charsConsumed = (int)(buffer - originalBuffer);
return(OperationStatus.NeedMoreData);
}
if (!TryEncodeUnicodeScalar(nextScalar, buffer, bufferLength, out int charsWrittenThisTime))
{
charsConsumed = (int)(buffer - originalBuffer);
return(OperationStatus.DestinationTooSmall);
}
buffer += charsWrittenThisTime;
bufferLength -= charsWrittenThisTime;
charsWritten += charsWrittenThisTime;
}
charsConsumed = valueLength;
return(OperationStatus.Done);
}
public static string Encode(this TextEncoder encoder, string value)
{
if (value == null)
{
return(value);
}
unsafe
{
fixed(char *valuePointer = value)
{
int firstCharacterToEncode = encoder.FindFirstCharacterToEncode(valuePointer, value.Length);
if (firstCharacterToEncode == -1)
{
return(value);
}
int bufferSize = encoder.MaxOutputCharsPerInputChar * value.Length;
char *wholebuffer = stackalloc char[bufferSize];
char *buffer = wholebuffer;
int totalWritten = 0;
if (firstCharacterToEncode > 0)
{
int bytesToCopy = firstCharacterToEncode + firstCharacterToEncode;
Buffer.MemoryCopy(valuePointer, buffer, bytesToCopy, bytesToCopy);
totalWritten += firstCharacterToEncode;
bufferSize -= firstCharacterToEncode;
buffer += firstCharacterToEncode;
}
int valueIndex = firstCharacterToEncode;
char firstChar = value[valueIndex];
char secondChar = firstChar;
bool wasSurrogatePair = false;
int charsWritten;
// this loop processes character pairs (in case they are surrogates).
// there is an if block below to process single last character.
for (int secondCharIndex = valueIndex + 1; secondCharIndex < value.Length; secondCharIndex++)
{
if (!wasSurrogatePair)
{
firstChar = secondChar;
}
else
{
firstChar = value[secondCharIndex - 1];
}
secondChar = value[secondCharIndex];
if (!encoder.Encodes(firstChar))
{
wasSurrogatePair = false;
*buffer = firstChar;
buffer++;
bufferSize--;
totalWritten++;
}
else
{
int nextScalar = UnicodeHelpers.GetScalarValueFromUtf16(firstChar, secondChar, out wasSurrogatePair);
if (!encoder.TryEncodeUnicodeScalar(nextScalar, buffer, bufferSize, out charsWritten))
{
throw new ArgumentException("Argument encoder does not implement MaxOutputCharsPerInputChar correctly.");
}
buffer += charsWritten;
bufferSize -= charsWritten;
totalWritten += charsWritten;
if (wasSurrogatePair)
{
secondCharIndex++;
}
}
}
if (!wasSurrogatePair)
{
firstChar = value[value.Length - 1];
int nextScalar = UnicodeHelpers.GetScalarValueFromUtf16(firstChar, null, out wasSurrogatePair);
if (!encoder.TryEncodeUnicodeScalar(nextScalar, buffer, bufferSize, out charsWritten))
{
throw new ArgumentException("Argument encoder does not implement MaxOutputCharsPerInputChar correctly.");
}
buffer += charsWritten;
bufferSize -= charsWritten;
totalWritten += charsWritten;
}
var result = new String(wholebuffer, 0, totalWritten);
return(result);
}
}
}
