public static uint ReadUnsigedNumber(this BufferReader reader, int n)
{
switch (n)
{
case 0: throw new NotSupportedException();
case 1: return(reader.ReadByte());
case 2:
{
uint b0 = reader.ReadByte(); //low bit
uint b1 = reader.ReadByte(); //high bit
return((b1 << 8) | (b0));
}
case 3:
{
uint b0 = reader.ReadByte(); //low bit
uint b1 = reader.ReadByte();
uint b2 = reader.ReadByte(); //high bit
return((b2 << 16) | (b1 << 8) | (b0));
}
case 4:
{
uint b0 = reader.ReadByte(); //low bit
uint b1 = reader.ReadByte();
uint b2 = reader.ReadByte();
uint b3 = reader.ReadByte(); //high bit
return((b3 << 24) | (b2 << 16) | (b1 << 8) | (b0));
}
default:
throw new Exception("parseUnsignedNumber: Supports only up to 4 bytes");
}
//if (bytes === 1)
//{
// return _buffer[_offset++];
//}
//var buffer = _buffer;
//var offset = _offset + bytes - 1;
//var value = 0;
//if (bytes > 4)
//{
// var err = new Error('parseUnsignedNumber: Supports only up to 4 bytes');
// err.offset = (_offset - _packetOffset - 1);
// err.code = 'PARSER_UNSIGNED_TOO_LONG';
// throw err;
//}
//long start = Position;
//long end = start + n - 1;
//while (offset >= _offset)
//{
// value = ((value << 8) | buffer[offset]) >>> 0;
// offset--;
//}
//_offset += bytes;
//return value;
//return value;
}
public static uint ReadLengthCodedNumber(this BufferReader reader, out bool isNullData)
{
isNullData = false;
byte bits = reader.ReadByte();
// if (bits <= 250)
// {
// return bits;
// }
if (bits <= 250)
{
return(bits);
}
// switch (bits)
// {
// case 251:
// return null;
// case 252:
// return this.parseUnsignedNumber(2);
// case 253:
// return this.parseUnsignedNumber(3);
// case 254:
// break;
// default:
// var err = new Error('Unexpected first byte' + (bits ? ': 0x' + bits.toString(16) : ''));
// err.offset = (_offset - _packetOffset - 1);
// err.code = 'PARSER_BAD_LENGTH_BYTE';
// throw err;
// }
switch (bits)
{
case 251:
isNullData = true;
return(0);
case 252: return(U2(reader));
case 253: return(U3(reader));
case 254: break;
default: throw new Exception("Unexpected first byte");
}
// var low = this.parseUnsignedNumber(4);
// var high = this.parseUnsignedNumber(4);
// var value;
uint low = U4(reader);
uint high = U4(reader);
//if ((uint)(high >> 21) > 0)
//{
// //TODO: review here
// //support big number
// long value = low + ((MUL_32BIT) * high);
//}
long len = low + ((MUL_32BIT)*high);
if (len < uint.MaxValue)
{
return((uint)len);
}
throw new NotSupportedException("big number!,please use " + nameof(ReadLengthCodedNumberInt64));
}
public static bool ReadLengthCodedDateTime(this BufferReader reader, out DateTime result)
{
byte dateLength = reader.ReadByte(); //***
int year = 0;
int month = 0;
int day = 0;
int hour = 0;
int minute = 0;
int second = 0;
int micro_second = 0;
//0, 4,7,11
switch (dateLength)
{
default:
case 0:
result = DateTime.MinValue;
return(false);
case 4:
year = (int)reader.U2();
month = reader.U1();
day = reader.U1();
result = new DateTime(year, month, day);
return(true);
case 7:
year = (int)reader.U2();
month = reader.U1();
day = reader.U1();
hour = reader.U1();
minute = reader.U1();
second = reader.U1();
result = new DateTime(year, month, day, hour, minute, second);
return(true);
case 11:
year = (int)reader.U2();
month = reader.U1();
day = reader.U1();
hour = reader.U1();
minute = reader.U1();
second = reader.U1();
micro_second = (int)reader.ReadUnsigedNumber(4);
result = new DateTime(year, month, day, hour, minute, second, micro_second / 1000);
return(true);
}
//if (dateLength == 0)
//{
// result = DateTime.MinValue;
// return false;
//}
//if (dateLength >= 4)
//{
// year = (int)ParseUnsigned2();
// month = ParseUnsigned1();
// day = ParseUnsigned1();
// dateTime = new DateTime(year, month, day);
//}
//if (dateLength >= 7)
//{
// hour = ParseUnsigned1();
// minute = ParseUnsigned1();
// second = ParseUnsigned1();
// dateTime = new DateTime(year, month, day, hour, minute, second);
//}
//if (dateLength == 11)
//{
// micro_second = (int)ParseUnsignedNumber(4);
// int milli_second = micro_second / 1000;
// dateTime = new DateTime(year, month, day, hour, minute, second, milli_second);
//}
//else
//{
// if (dateLength == 7)
// {
// dateTime = new DateTime(year, month, day, hour, minute, second);
// }
// else if (dateLength == 4)
// {
// dateTime = new DateTime(year, month, day);
// }
// else
// {
// dateTime = new DateTime(0, 0, 0, 0, 0, 0, 0, 0);
// }
//}
//return dateTime;
}
public static string ReadString(this BufferReader reader,
uint length,
IStringConverter strConverter)
{
return(strConverter.ReadConv(reader.ReadBytes((int)length)));
}
public static byte[] ReadLengthCodedBuffer(this BufferReader reader)
{
byte[] output = ReadLengthCodedBuffer(reader, out bool isNull);
return(isNull ? null : output);
}
/// <summary>
/// read unsigned 1 byte
/// </summary>
/// <returns></returns>
public static byte U1(this BufferReader bufferReader)
{
return(bufferReader.ReadByte());
}
public static long ReadLengthCodedNumberInt64(this BufferReader reader, out bool isNullData)
{
isNullData = false;
byte bits = reader.ReadByte();
if (bits <= 250)
{
return(bits);
}
// switch (bits)
// {
// case 251:
// return null;
// case 252:
// return this.parseUnsignedNumber(2);
// case 253:
// return this.parseUnsignedNumber(3);
// case 254:
// break;
// default:
// var err = new Error('Unexpected first byte' + (bits ? ': 0x' + bits.toString(16) : ''));
// err.offset = (_offset - _packetOffset - 1);
// err.code = 'PARSER_BAD_LENGTH_BYTE';
// throw err;
// }
switch (bits)
{
case 251:
isNullData = true;
return(0);
case 252: return(U2(reader));
case 253: return(U3(reader));
case 254: break;
default: throw new Exception("Unexpected first byte");
}
// var low = this.parseUnsignedNumber(4);
// var high = this.parseUnsignedNumber(4);
// var value;
uint low = U4(reader);
uint high = U4(reader);
//if ((uint)(high >> 21) > 0)
//{
// //TODO: review here
// //support big number
// long value = low + ((MUL_32BIT) * high);
//}
return(low + ((MUL_32BIT)*high));
//if (high >>> 21)
//{
// value = (new BigNumber(low)).plus((new BigNumber(MUL_32BIT)).times(high)).toString();
// if (_supportBigNumbers)
// {
// return value;
// }
// var err = new Error(
// 'parseLengthCodedNumber: JS precision range exceeded, ' +
// 'number is >= 53 bit: "' + value + '"'
// );
// err.offset = (_offset - _packetOffset - 8);
// err.code = 'PARSER_JS_PRECISION_RANGE_EXCEEDED';
// throw err;
//}
//value = low + (MUL_32BIT * high);
//return value;
}