public static bool TryFormat(this DateTime value, Span<byte> buffer, Format.Parsed format, FormattingData formattingData, out int bytesWritten)
{
if (format.IsDefault)
{
format.Symbol = 'G';
}
Precondition.Require(format.Symbol == 'R' || format.Symbol == 'O' || format.Symbol == 'G');
switch (format.Symbol)
{
case 'R':
var utc = value.ToUniversalTime();
if (formattingData.IsUtf16)
{
return TryFormatDateTimeRfc1123(utc, buffer, FormattingData.InvariantUtf16, out bytesWritten);
}
else
{
return TryFormatDateTimeRfc1123(utc, buffer, FormattingData.InvariantUtf8, out bytesWritten);
}
case 'O':
if (formattingData.IsUtf16)
{
return TryFormatDateTimeFormatO(value, true, buffer, FormattingData.InvariantUtf16, out bytesWritten);
}
else
{
return TryFormatDateTimeFormatO(value, true, buffer, FormattingData.InvariantUtf8, out bytesWritten);
}
case 'G':
return TryFormatDateTimeFormagG(value, buffer, formattingData, out bytesWritten);
default:
throw new NotImplementedException();
}
}
internal static bool TryFormatUInt64(ulong value, byte numberOfBytes, Span<byte> buffer, Format.Parsed format, FormattingData formattingData, out int bytesWritten)
{
if(format.Symbol == 'g')
{
format.Symbol = 'G';
}
if (format.IsHexadecimal && formattingData.IsUtf16) {
return TryFormatHexadecimalInvariantCultureUtf16(value, buffer, format, out bytesWritten);
}
if (format.IsHexadecimal && formattingData.IsUtf8) {
return TryFormatHexadecimalInvariantCultureUtf8(value, buffer, format, out bytesWritten);
}
if ((formattingData.IsInvariantUtf16) && (format.Symbol == 'D' || format.Symbol == 'G')) {
return TryFormatDecimalInvariantCultureUtf16(value, buffer, format, out bytesWritten);
}
if ((formattingData.IsInvariantUtf8) && (format.Symbol == 'D' || format.Symbol == 'G')) {
return TryFormatDecimalInvariantCultureUtf8(value, buffer, format, out bytesWritten);
}
return TryFormatDecimal(value, buffer, format, formattingData, out bytesWritten);
}
internal static bool TryFormatInt64(long value, byte numberOfBytes, Span<byte> buffer, Format.Parsed format, FormattingData formattingData, out int bytesWritten)
{
Precondition.Require(numberOfBytes <= sizeof(long));
if (value >= 0)
{
return TryFormatUInt64(unchecked((ulong)value), numberOfBytes, buffer, format, formattingData, out bytesWritten);
}
else if (format.IsHexadecimal)
{
ulong bitMask = GetBitMask(numberOfBytes);
return TryFormatUInt64(unchecked((ulong)value) & bitMask, numberOfBytes, buffer, format, formattingData, out bytesWritten);
}
else
{
int minusSignBytes = 0;
if(!formattingData.TryWriteSymbol(FormattingData.Symbol.MinusSign, buffer, out minusSignBytes))
{
bytesWritten = 0;
return false;
}
int digitBytes = 0;
if(!TryFormatUInt64(unchecked((ulong)-value), numberOfBytes, buffer.Slice(minusSignBytes), format, formattingData, out digitBytes))
{
bytesWritten = 0;
return false;
}
bytesWritten = digitBytes + minusSignBytes;
return true;
}
}
public static bool TryFormat(this float value, Span<byte> buffer, Format.Parsed format, FormattingData formattingData, out int bytesWritten)
{
if (format.IsDefault)
{
format.Symbol = 'G';
}
Precondition.Require(format.Symbol == 'G');
return FloatFormatter.TryFormatNumber(value, true, buffer, format, formattingData, out bytesWritten);
}
public bool TryFormat(Span<byte> buffer, Format.Parsed format, FormattingData formattingData, out int bytesWritten)
{
if (!PrimitiveFormatters.TryFormat(_age, buffer, format, formattingData, out bytesWritten)) return false;
char symbol = _inMonths ? 'm' : 'y';
int symbolBytes;
if (!PrimitiveFormatters.TryFormat(symbol, buffer.Slice(bytesWritten), format, formattingData, out symbolBytes)) return false;
bytesWritten += symbolBytes;
return true;
}
public static bool TryFormat(this char value, Span<byte> buffer, Format.Parsed format, FormattingData formattingData, out int bytesWritten)
{
if (formattingData.IsUtf16)
{
if (buffer.Length < 2)
{
bytesWritten = 0;
return false;
}
buffer[0] = (byte)value;
buffer[1] = (byte)(value >> 8);
bytesWritten = 2;
return true;
}
if (buffer.Length < 1)
{
bytesWritten = 0;
return false;
}
// fast path for ASCII
if (value <= 127)
{
buffer[0] = (byte)value;
bytesWritten = 1;
return true;
}
// TODO: This can be directly encoded to SpanByte. There is no conversion between spans yet
var encoded = new Utf8EncodedCodePoint(value);
bytesWritten = encoded.Length;
if (buffer.Length < bytesWritten)
{
bytesWritten = 0;
return false;
}
buffer[0] = encoded.Byte0;
if(bytesWritten > 1)
{
buffer[1] = encoded.Byte1;
}
if(bytesWritten > 2)
{
buffer[2] = encoded.Byte2;
}
if(bytesWritten > 3)
{
buffer[3] = encoded.Byte3;
}
return true;
}
public static bool TryFormat(this char value, Span<byte> buffer, Format.Parsed format, FormattingData formattingData, out int bytesWritten)
{
if (formattingData.IsUtf16)
{
if (buffer.Length < 2)
{
bytesWritten = 0;
return false;
}
buffer[0] = (byte)value;
buffer[1] = (byte)(value >> 8);
bytesWritten = 2;
return true;
}
if (buffer.Length < 1)
{
bytesWritten = 0;
return false;
}
// fast path for ASCII
if (value <= 127)
{
buffer[0] = (byte)value;
bytesWritten = 1;
return true;
}
var encoded = new FourBytes();
bytesWritten = Utf8Encoder.CharToUtf8(value, ref encoded);
if(buffer.Length < bytesWritten)
{
bytesWritten = 0;
return false;
}
buffer[0] = encoded.B0;
if(bytesWritten > 1)
{
buffer[1] = encoded.B1;
}
if(bytesWritten > 2)
{
buffer[2] = encoded.B2;
}
if(bytesWritten > 3)
{
buffer[3] = encoded.B3;
}
return true;
}
private static bool TryFormatDecimalInvariantCultureUtf16(ulong value, Span<byte> buffer, Format.Parsed format, out int bytesWritten)
{
Precondition.Require(format.Symbol == 'D' || format.Symbol == 'G');
// Count digits
var valueToCountDigits = value;
var digitsCount = 1;
while (valueToCountDigits >= 10UL) {
valueToCountDigits = valueToCountDigits / 10UL;
digitsCount++;
}
var index = 0;
var bytesCount = digitsCount * 2;
// If format is D and precision is greater than digits count, append leading zeros
if (format.Symbol == 'D' && format.HasPrecision) {
var leadingZerosCount = format.Precision - digitsCount;
if (leadingZerosCount > 0) {
bytesCount += leadingZerosCount * 2;
}
if (bytesCount > buffer.Length) {
bytesWritten = 0;
return false;
}
while (leadingZerosCount-- > 0) {
buffer[index++] = (byte)'0';
buffer[index++] = 0;
}
}
else if (bytesCount > buffer.Length) {
bytesWritten = 0;
return false;
}
index = bytesCount;
while (digitsCount-- > 0) {
ulong digit = value % 10UL;
value /= 10UL;
buffer[--index] = 0;
buffer[--index] = (byte)(digit + (ulong)'0');
}
bytesWritten = bytesCount;
return true;
}
public static bool TryFormatNumber(double value, bool isSingle, Span<byte> buffer, Format.Parsed format, FormattingData formattingData, out int bytesWritten)
{
Precondition.Require(format.Symbol == 'G' || format.Symbol == 'E' || format.Symbol == 'F');
bytesWritten = 0;
int written;
if (Double.IsNaN(value))
{
return formattingData.TryWriteSymbol(FormattingData.Symbol.NaN, buffer, out bytesWritten);
}
if (Double.IsInfinity(value))
{
if (Double.IsNegativeInfinity(value))
{
if (!formattingData.TryWriteSymbol(FormattingData.Symbol.MinusSign, buffer, out written))
{
bytesWritten = 0;
return false;
}
bytesWritten += written;
}
if (!formattingData.TryWriteSymbol(FormattingData.Symbol.InfinitySign, buffer.Slice(bytesWritten), out written))
{
bytesWritten = 0;
return false;
}
bytesWritten += written;
return true;
}
// TODO: the lines below need to be replaced with properly implemented algorithm
// the problem is the algorithm is complex, so I am commiting a stub for now
var hack = value.ToString(format.Symbol.ToString());
return hack.TryFormat(buffer, default(Format.Parsed), formattingData, out bytesWritten);
}
private static void Verify(Format.Parsed format, byte expectedPrecision, char expectedSymbol)
{
Assert.Equal(format.Precision, expectedPrecision);
Assert.Equal(format.Symbol, expectedSymbol.ToString()[0]);
}
private static bool TryFormatTimeSpanG(TimeSpan value, Span<byte> buffer, Format.Parsed format, FormattingData formattingData, out int bytesWritten)
{
bytesWritten = 0;
if (value.Ticks < 0)
{
if (!TryWriteChar('-', buffer, formattingData, ref bytesWritten)) { return false; }
}
bool daysWritten = false;
if (value.Days != 0 || format.Symbol == 'G')
{
if (!TryWriteInt32(Abs(value.Days), buffer, default(Format.Parsed), formattingData, ref bytesWritten)) { return false; }
daysWritten = true;
if (format.Symbol == 'c')
{
if (!TryWriteChar('.', buffer, formattingData, ref bytesWritten)) { return false; }
}
else
{
if (!TryWriteChar(':', buffer, formattingData, ref bytesWritten)) { return false; }
}
}
var hourFormat = default(Format.Parsed);
if ((daysWritten || format.Symbol == 'c') && format.Symbol != 'g')
{
hourFormat = D2;
}
if (!TryWriteInt32(Abs(value.Hours), buffer, hourFormat, formattingData, ref bytesWritten)) { return false; }
if (!TryWriteChar(':', buffer, formattingData, ref bytesWritten)) { return false; }
if (!TryWriteInt32(Abs(value.Minutes), buffer, D2, formattingData, ref bytesWritten)) { return false; }
if (!TryWriteChar(':', buffer, formattingData, ref bytesWritten)) { return false; }
if (!TryWriteInt32(Abs(value.Seconds), buffer, D2, formattingData, ref bytesWritten)) { return false; }
long remainingTicks;
if (value.Ticks != long.MinValue)
{
remainingTicks = Abs(value.Ticks) % TimeSpan.TicksPerSecond;
}
else
{
remainingTicks = long.MaxValue % TimeSpan.TicksPerSecond;
remainingTicks = (remainingTicks + 1) % TimeSpan.TicksPerSecond;
}
var ticksFormat = D7;
if (remainingTicks != 0)
{
if (!TryWriteChar('.', buffer, formattingData, ref bytesWritten)) { return false; }
var fraction = remainingTicks * FractionalTimeScale / TimeSpan.TicksPerSecond;
if (!TryWriteInt64(fraction, buffer, ticksFormat, formattingData, ref bytesWritten)) { return false; }
}
return true;
}
public static bool TryFormat(this DateTime value, Span <byte> buffer, ReadOnlySpan <char> format, FormattingData formattingData, out int bytesWritten)
{
Format.Parsed parsedFormat = Format.Parse(format);
return(TryFormat(value, buffer, parsedFormat, formattingData, out bytesWritten));
}
public static bool TryFormat(this Guid value, Span<byte> buffer, Format.Parsed format, FormattingData formattingData, out int bytesWritten)
{
if (format.IsDefault)
{
format.Symbol = 'G';
}
Precondition.Require(format.Symbol == 'G' || format.Symbol == 'D' || format.Symbol == 'N' || format.Symbol == 'B' || format.Symbol == 'P');
bool dash = true;
char tail = '\0';
bytesWritten = 0;
switch (format.Symbol)
{
case 'D':
case 'G':
break;
case 'N':
dash = false;
break;
case 'B':
if (!TryWriteChar('{', buffer, formattingData, ref bytesWritten)) { return false; }
tail = '}';
break;
case 'P':
if (!TryWriteChar('(', buffer, formattingData, ref bytesWritten)) { return false; }
tail = ')';
break;
default:
Precondition.Require(false); // how did we get here?
break;
}
var byteFormat = new Format.Parsed('x', 2);
unsafe
{
byte* bytes = (byte*)&value;
if (!TryWriteByte(bytes[3], buffer, byteFormat, formattingData, ref bytesWritten)) { return false; }
if (!TryWriteByte(bytes[2], buffer, byteFormat, formattingData, ref bytesWritten)) { return false; }
if (!TryWriteByte(bytes[1], buffer, byteFormat, formattingData, ref bytesWritten)) { return false; }
if (!TryWriteByte(bytes[0], buffer, byteFormat, formattingData, ref bytesWritten)) { return false; }
if (dash)
{
if (!TryWriteChar('-', buffer, formattingData, ref bytesWritten)) { return false; }
}
if (!TryWriteByte(bytes[5], buffer, byteFormat, formattingData, ref bytesWritten)) { return false; }
if (!TryWriteByte(bytes[4], buffer, byteFormat, formattingData, ref bytesWritten)) { return false; }
if (dash)
{
if (!TryWriteChar('-', buffer, formattingData, ref bytesWritten)) { return false; }
}
if (!TryWriteByte(bytes[7], buffer, byteFormat, formattingData, ref bytesWritten)) { return false; }
if (!TryWriteByte(bytes[6], buffer, byteFormat, formattingData, ref bytesWritten)) { return false; }
if (dash)
{
if (!TryWriteChar('-', buffer, formattingData, ref bytesWritten)) { return false; }
}
if (!TryWriteByte(bytes[8], buffer, byteFormat, formattingData, ref bytesWritten)) { return false; }
if (!TryWriteByte(bytes[9], buffer, byteFormat, formattingData, ref bytesWritten)) { return false; }
if (dash)
{
if (!TryWriteChar('-', buffer, formattingData, ref bytesWritten)) { return false; }
}
if (!TryWriteByte(bytes[10], buffer, byteFormat, formattingData, ref bytesWritten)) { return false; }
if (!TryWriteByte(bytes[11], buffer, byteFormat, formattingData, ref bytesWritten)) { return false; }
if (!TryWriteByte(bytes[12], buffer, byteFormat, formattingData, ref bytesWritten)) { return false; }
if (!TryWriteByte(bytes[13], buffer, byteFormat, formattingData, ref bytesWritten)) { return false; }
if (!TryWriteByte(bytes[14], buffer, byteFormat, formattingData, ref bytesWritten)) { return false; }
if (!TryWriteByte(bytes[15], buffer, byteFormat, formattingData, ref bytesWritten)) { return false; }
}
if (tail != '\0')
{
if (!TryWriteChar(tail, buffer, formattingData, ref bytesWritten)) { return false; }
}
return true;
}
public static bool TryFormat(this TimeSpan value, Span<byte> buffer, Format.Parsed format, FormattingData formattingData, out int bytesWritten)
{
if (format.IsDefault)
{
format.Symbol = 'c';
}
Precondition.Require(format.Symbol == 'G' || format.Symbol == 't' || format.Symbol == 'c' || format.Symbol == 'g');
if (format.Symbol != 't')
{
return TryFormatTimeSpanG(value, buffer, format, formattingData, out bytesWritten);
}
// else it's format 't' (short time used to print time offsets)
return TryFormatTimeSpanT(value, buffer, formattingData, out bytesWritten);
}
public static bool TryFormat(this string value, Span<byte> buffer, Format.Parsed format, FormattingData formattingData, out int bytesWritten)
{
if (formattingData.IsUtf16)
{
var valueBytes = value.Length << 1;
if (valueBytes > buffer.Length)
{
bytesWritten = 0;
return false;
}
unsafe
{
fixed (char* pCharacters = value)
{
byte* pBytes = (byte*)pCharacters;
buffer.Set(pBytes, valueBytes);
}
}
bytesWritten = valueBytes;
return true;
}
GCHandle handle;
var byteSpan = buffer.Pin(out handle);
try {
var avaliableBytes = byteSpan.Length;
bytesWritten = 0;
for (int i = 0; i < value.Length; i++)
{
var c = value[i];
var codepoint = (ushort)c;
if (codepoint <= 0x7f) // this if block just optimizes for ascii
{
if (bytesWritten + 1 > avaliableBytes)
{
bytesWritten = 0;
return false;
}
byteSpan[bytesWritten++] = (byte)codepoint;
}
else
{
var encoded = new FourBytes();
var bytes = Utf8Encoder.CharToUtf8(c, ref encoded);
if (bytesWritten + bytes > avaliableBytes)
{
bytesWritten = 0;
return false;
}
byteSpan[bytesWritten] = encoded.B0;
if (bytes > 1)
{
byteSpan[bytesWritten + 1] = encoded.B1;
if (bytes > 2)
{
byteSpan[bytesWritten + 2] = encoded.B2;
if (bytes > 3)
{
byteSpan[bytesWritten + 3] = encoded.B3;
}
}
}
bytesWritten += bytes;
}
}
return true;
}
finally
{
handle.Free();
}
}
static bool TryWriteInt64(long i, Span<byte> buffer, Format.Parsed byteFormat, FormattingData formattingData, ref int bytesWritten)
{
int written;
if (!i.TryFormat(buffer.Slice(bytesWritten), byteFormat, formattingData, out written))
{
bytesWritten = 0;
return false;
}
bytesWritten += written;
return true;
}
public static bool TryFormat(this Utf8String value, Span<byte> buffer, Format.Parsed format, FormattingData formattingData, out int bytesWritten)
{
if (formattingData.IsUtf16) {
throw new NotImplementedException();
}
if(buffer.Length < value.Length) {
bytesWritten = 0;
return false;
}
buffer.Set(value.Bytes);
bytesWritten = value.Length;
return true;
}
// TODO: this whole routine is too slow. It does div and mod twice, which are both costly (especially that some JITs cannot optimize it).
// It does it twice to avoid reversing the formatted buffer, which can be tricky given it should handle arbitrary cultures.
// One optimization I thought we could do is to do div/mod once and store digits in a temp buffer (but that would allocate). Modification to the idea would be to store the digits in a local struct
// Another idea possibly worth tying would be to special case cultures that have constant digit size, and go back to the format + reverse buffer approach.
private static bool TryFormatDecimal(ulong value, Span<byte> buffer, Format.Parsed format, FormattingData formattingData, out int bytesWritten)
{
if(format.IsDefault)
{
format.Symbol = 'G';
}
format.Symbol = Char.ToUpperInvariant(format.Symbol); // TODO: this is costly. I think the transformation should happen in Parse
Precondition.Require(format.Symbol == 'D' || format.Symbol == 'G' || format.Symbol == 'N');
// Reverse value on decimal basis, count digits and trailing zeros before the decimal separator
ulong reversedValueExceptFirst = 0;
var digitsCount = 1;
var trailingZerosCount = 0;
// We reverse the digits in numeric form because reversing encoded digits is hard and/or costly.
// If value contains 20 digits, its reversed value will not fit into ulong size.
// So reverse it till last digit (reversedValueExceptFirst will have all the digits except the first one).
while (value >= 10)
{
var digit = value % 10UL;
value = value / 10UL;
if (reversedValueExceptFirst == 0 && digit == 0)
{
trailingZerosCount++;
}
else
{
reversedValueExceptFirst = reversedValueExceptFirst * 10UL + digit;
digitsCount++;
}
}
bytesWritten = 0;
int digitBytes;
// If format is D and precision is greater than digitsCount + trailingZerosCount, append leading zeros
if (format.Symbol == 'D' && format.HasPrecision)
{
var leadingZerosCount = format.Precision - digitsCount - trailingZerosCount;
while (leadingZerosCount-- > 0)
{
if (!formattingData.TryWriteDigitOrSymbol(0, buffer.Slice(bytesWritten), out digitBytes))
{
bytesWritten = 0;
return false;
}
bytesWritten += digitBytes;
}
}
// Append first digit
if (!formattingData.TryWriteDigit(value, buffer.Slice(bytesWritten), out digitBytes))
{
bytesWritten = 0;
return false;
}
bytesWritten += digitBytes;
digitsCount--;
if (format.Symbol == 'N')
{
const int GroupSize = 3;
// Count amount of digits before first group separator. It will be reset to groupSize every time digitsLeftInGroup == zero
var digitsLeftInGroup = (digitsCount + trailingZerosCount) % GroupSize;
if (digitsLeftInGroup == 0)
{
if (digitsCount + trailingZerosCount > 0)
{
// There is a new group immediately after the first digit
if (!formattingData.TryWriteSymbol(FormattingData.Symbol.GroupSeparator, buffer.Slice(bytesWritten), out digitBytes))
{
bytesWritten = 0;
return false;
}
bytesWritten += digitBytes;
}
digitsLeftInGroup = GroupSize;
}
// Append digits
while (reversedValueExceptFirst > 0)
{
if (digitsLeftInGroup == 0)
{
if (!formattingData.TryWriteSymbol(FormattingData.Symbol.GroupSeparator, buffer.Slice(bytesWritten), out digitBytes))
{
bytesWritten = 0;
return false;
}
bytesWritten += digitBytes;
digitsLeftInGroup = GroupSize;
}
var nextDigit = reversedValueExceptFirst % 10UL;
reversedValueExceptFirst = reversedValueExceptFirst / 10UL;
if (!formattingData.TryWriteDigit(nextDigit, buffer.Slice(bytesWritten), out digitBytes))
{
bytesWritten = 0;
return false;
}
bytesWritten += digitBytes;
digitsLeftInGroup--;
}
// Append trailing zeros if any
while (trailingZerosCount-- > 0)
{
if (digitsLeftInGroup == 0)
{
if (!formattingData.TryWriteSymbol(FormattingData.Symbol.GroupSeparator, buffer.Slice(bytesWritten), out digitBytes))
{
bytesWritten = 0;
return false;
}
bytesWritten += digitBytes;
digitsLeftInGroup = GroupSize;
}
if (!formattingData.TryWriteDigitOrSymbol(0, buffer.Slice(bytesWritten), out digitBytes))
{
bytesWritten = 0;
return false;
}
bytesWritten += digitBytes;
digitsLeftInGroup--;
}
}
else
{
while (reversedValueExceptFirst > 0)
{
var bufferSlice = buffer.Slice(bytesWritten);
var nextDigit = reversedValueExceptFirst % 10UL;
reversedValueExceptFirst = reversedValueExceptFirst / 10UL;
if (!formattingData.TryWriteDigit(nextDigit, bufferSlice, out digitBytes))
{
bytesWritten = 0;
return false;
}
bytesWritten += digitBytes;
}
// Append trailing zeros if any
while (trailingZerosCount-- > 0)
{
if (!formattingData.TryWriteDigitOrSymbol(0, buffer.Slice(bytesWritten), out digitBytes))
{
bytesWritten = 0;
return false;
}
bytesWritten += digitBytes;
}
}
// If format is N and precision is not defined or is greater than zero, append trailing zeros after decimal point
if (format.Symbol == 'N')
{
int trailingZerosAfterDecimalCount = format.HasPrecision ? format.Precision : 2;
if (trailingZerosAfterDecimalCount > 0)
{
if (!formattingData.TryWriteSymbol(FormattingData.Symbol.DecimalSeparator, buffer.Slice(bytesWritten), out digitBytes))
{
bytesWritten = 0;
return false;
}
bytesWritten += digitBytes;
while (trailingZerosAfterDecimalCount-- > 0)
{
if (!formattingData.TryWriteDigitOrSymbol(0, buffer.Slice(bytesWritten), out digitBytes))
{
bytesWritten = 0;
return false;
}
bytesWritten += digitBytes;
}
}
}
return true;
}
private static bool TryFormatHexadecimalInvariantCultureUtf8(ulong value, Span<byte> buffer, Format.Parsed format, out int bytesWritten)
{
Precondition.Require(format.Symbol == 'X' || format.Symbol == 'X');
byte firstDigitOffset = (byte)'0';
byte firstHexCharOffset = format.Symbol == 'X' ? (byte)'a' : (byte)'A';
firstHexCharOffset -= 10;
// Count amount of hex digits
var hexDigitsCount = 1;
ulong valueToCount = value;
if (valueToCount > 0xFFFFFFFF)
{
hexDigitsCount += 8;
valueToCount >>= 0x20;
}
if (valueToCount > 0xFFFF)
{
hexDigitsCount += 4;
valueToCount >>= 0x10;
}
if (valueToCount > 0xFF)
{
hexDigitsCount += 2;
valueToCount >>= 0x8;
}
if (valueToCount > 0xF)
{
hexDigitsCount++;
}
var bytesCount = hexDigitsCount;
// Count leading zeros
var leadingZerosCount = format.HasPrecision ? format.Precision - hexDigitsCount : 0;
bytesCount += leadingZerosCount > 0 ? leadingZerosCount : 0;
if (bytesCount > buffer.Length)
{
bytesWritten = 0;
return false;
}
var index = bytesCount;
while (hexDigitsCount-- > 0)
{
byte digit = (byte)(value & 0xF);
value >>= 0x4;
digit += digit < 10 ? firstDigitOffset : firstHexCharOffset;
buffer[--index] = digit;
}
// Write leading zeros if any
while (leadingZerosCount-- > 0)
{
buffer[--index] = firstDigitOffset;
}
bytesWritten = bytesCount;
return true;
}
public static bool TryFormat(this string value, Span<byte> buffer, Format.Parsed format, FormattingData formattingData, out int bytesWritten)
{
if (formattingData.IsUtf16)
{
var valueBytes = value.Length << 1;
if (valueBytes > buffer.Length)
{
bytesWritten = 0;
return false;
}
unsafe
{
fixed (char* pCharacters = value)
{
byte* pBytes = (byte*)pCharacters;
buffer.Set(pBytes, valueBytes);
}
}
bytesWritten = valueBytes;
return true;
}
GCHandle handle;
var byteSpan = buffer.Pin(out handle);
try {
var avaliableBytes = byteSpan.Length;
bytesWritten = 0;
for (int i = 0; i < value.Length; i++)
{
var c = value[i];
var codepoint = (ushort)c;
if (codepoint <= 0x7f) // this if block just optimizes for ascii
{
if (bytesWritten + 1 > avaliableBytes)
{
bytesWritten = 0;
return false;
}
byteSpan[bytesWritten++] = (byte)codepoint;
}
else
{
Utf8EncodedCodePoint encoded;
if (!char.IsSurrogate(c))
encoded = new Utf8EncodedCodePoint(c);
else
{
if (++i >= value.Length)
throw new ArgumentException("value", "Invalid surrogate pair.");
char lowSurrogate = value[i];
encoded = new Utf8EncodedCodePoint(c, lowSurrogate);
}
if (bytesWritten + encoded.Length > avaliableBytes)
{
bytesWritten = 0;
return false;
}
byteSpan[bytesWritten] = encoded.Byte0;
if (encoded.Length > 1)
{
byteSpan[bytesWritten + 1] = encoded.Byte1;
if (encoded.Length > 2)
{
byteSpan[bytesWritten + 2] = encoded.Byte2;
if (encoded.Length > 3)
{
byteSpan[bytesWritten + 3] = encoded.Byte3;
}
}
}
bytesWritten += encoded.Length;
}
}
return true;
}
finally
{
handle.Free();
}
}
public static bool TryFormat(this long value, Span<byte> buffer, Format.Parsed format, FormattingData formattingData, out int bytesWritten)
{
return IntegerFormatter.TryFormatInt64(value, 8, buffer, format, formattingData, out bytesWritten);
}