private static WebSocketFrame read(byte[] header, Stream stream, bool unmask)
{
/* Header */
// FIN
var fin = (header[0] & 0x80) == 0x80 ? Fin.Final : Fin.More;
// RSV1
var rsv1 = (header[0] & 0x40) == 0x40 ? Rsv.On : Rsv.Off;
// RSV2
var rsv2 = (header[0] & 0x20) == 0x20 ? Rsv.On : Rsv.Off;
// RSV3
var rsv3 = (header[0] & 0x10) == 0x10 ? Rsv.On : Rsv.Off;
// Opcode
var opcode = (Opcode)(header[0] & 0x0f);
// MASK
var mask = (header[1] & 0x80) == 0x80 ? Mask.Mask : Mask.Unmask;
// Payload Length
var payloadLen = (byte)(header[1] & 0x7f);
// Check if valid header
var err = isControl(opcode) && payloadLen > 125
? "A control frame has a payload data which is greater than the allowable max size."
: isControl(opcode) && fin == Fin.More
? "A control frame is fragmented."
: !isData(opcode) && rsv1 == Rsv.On
? "A non data frame is compressed."
: null;
if (err != null)
{
throw new WebSocketException(CloseStatusCode.ProtocolError, err);
}
var frame = new WebSocketFrame();
frame._fin = fin;
frame._rsv1 = rsv1;
frame._rsv2 = rsv2;
frame._rsv3 = rsv3;
frame._opcode = opcode;
frame._mask = mask;
frame._payloadLength = payloadLen;
/* Extended Payload Length */
var size = payloadLen < 126
? 0
: payloadLen == 126
? 2
: 8;
var extPayloadLen = size > 0 ? stream.ReadBytes(size) : new byte[0];
if (size > 0 && extPayloadLen.Length != size)
{
throw new WebSocketException(
"The 'Extended Payload Length' of a frame cannot be read from the data source.");
}
frame._extPayloadLength = extPayloadLen;
/* Masking Key */
var masked = mask == Mask.Mask;
var maskingKey = masked ? stream.ReadBytes(4) : new byte[0];
if (masked && maskingKey.Length != 4)
{
throw new WebSocketException(
"The 'Masking Key' of a frame cannot be read from the data source.");
}
frame._maskingKey = maskingKey;
/* Payload Data */
ulong len = payloadLen < 126
? payloadLen
: payloadLen == 126
? extPayloadLen.ToUInt16(ByteOrder.Big)
: extPayloadLen.ToUInt64(ByteOrder.Big);
byte[] data = null;
if (len > 0)
{
// Check if allowable max length.
if (payloadLen > 126 && len > PayloadData.MaxLength)
{
throw new WebSocketException(
CloseStatusCode.TooBig,
"The length of 'Payload Data' of a frame is greater than the allowable max length.");
}
data = payloadLen > 126
? stream.ReadBytes((long)len, 1024)
: stream.ReadBytes((int)len);
if (data.LongLength != (long)len)
{
throw new WebSocketException(
"The 'Payload Data' of a frame cannot be read from the data source.");
}
}
else
{
data = new byte[0];
}
frame._payloadData = new PayloadData(data, masked);
if (unmask && masked)
{
frame.Unmask();
}
return(frame);
}
internal MessageEventArgs(WebSocketFrame frame)
{
_opcode = frame.Opcode;
_rawData = frame.PayloadData.ApplicationData;
_data = convertToString(_opcode, _rawData);
}
private static string dump(WebSocketFrame frame)
{
var len = frame.Length;
var cnt = (long)(len / 4);
var rem = (int)(len % 4);
int cntDigit;
string cntFmt;
if (cnt < 10000)
{
cntDigit = 4;
cntFmt = "{0,4}";
}
else if (cnt < 0x010000)
{
cntDigit = 4;
cntFmt = "{0,4:X}";
}
else if (cnt < 0x0100000000)
{
cntDigit = 8;
cntFmt = "{0,8:X}";
}
else
{
cntDigit = 16;
cntFmt = "{0,16:X}";
}
var spFmt = String.Format("{{0,{0}}}", cntDigit);
var headerFmt = String.Format(@"
{0} 01234567 89ABCDEF 01234567 89ABCDEF
{0}+--------+--------+--------+--------+\n", spFmt);
var lineFmt = String.Format("{0}|{{1,8}} {{2,8}} {{3,8}} {{4,8}}|\n", cntFmt);
var footerFmt = String.Format("{0}+--------+--------+--------+--------+", spFmt);
var output = new StringBuilder(64);
Func <Action <string, string, string, string> > linePrinter = () => {
long lineCnt = 0;
return((arg1, arg2, arg3, arg4) =>
output.AppendFormat(lineFmt, ++lineCnt, arg1, arg2, arg3, arg4));
};
output.AppendFormat(headerFmt, String.Empty);
var printLine = linePrinter();
var bytes = frame.ToByteArray();
for (long i = 0; i <= cnt; i++)
{
var j = i * 4;
if (i < cnt)
{
printLine(
Convert.ToString(bytes[j], 2).PadLeft(8, '0'),
Convert.ToString(bytes[j + 1], 2).PadLeft(8, '0'),
Convert.ToString(bytes[j + 2], 2).PadLeft(8, '0'),
Convert.ToString(bytes[j + 3], 2).PadLeft(8, '0'));
}
else if (rem > 0)
{
printLine(
Convert.ToString(bytes[j], 2).PadLeft(8, '0'),
rem >= 2 ? Convert.ToString(bytes[j + 1], 2).PadLeft(8, '0') : String.Empty,
rem == 3 ? Convert.ToString(bytes[j + 2], 2).PadLeft(8, '0') : String.Empty,
String.Empty);
}
}
output.AppendFormat(footerFmt, String.Empty);
return(output.ToString());
}
