public override int Read(byte[] buffer, int offset, int count)
{
int remain = count;
while (remain > 0)
{
DepackFrameHeaderIfNesseary();
int len = Math.Min(_payloadRemain, remain);
int got = TryRead(buffer, offset, len);
_payloadcrc32 = CRC32.GetCRC32Byte(buffer, offset, got, _payloadcrc32);
offset += got;
remain -= got;
_payloadRemain -= got;
if (_gotEndFrame || _gotEndofStream)
{
break;
}
}
return(count - remain);
}
public void DepackFrameHeaderIfNesseary()
{
var buff = new byte[128];
int readCnt = 0;
//Version | Frame - Type | Payload Length | Header Checksum | Payload | Payload Checksum
//<1 bytes> <--3 bytes--> <-- 4 bytes --> <------4 bytes--> <variable><----4bytes------>
//Payload
//<offset | data>
//<8 bytes><variable>
if (_payloadRemain > 0)
{
return;
}
if (_lastFrameType == 0x800001)
{
//Payload Checksum
readCnt = TryRead(buff, 0, 4);
ensureReadSize(4, readCnt);
uint serverCrc32 = OssUtils.ConvertBytesToUint(buff, 0, 4);
//Payload Crc32 check
if (serverCrc32 != 0 && serverCrc32 != _payloadcrc32)
{
throw new ClientException(string.Format("Payload checksum check fail server CRC {0}, client CRC {1}",
serverCrc32, _payloadcrc32));
}
}
_lastFrameType = 0;
_payloadRemain = 0;
readCnt = TryRead(buff, 0, 12);
if (_gotEndofStream)
{
return;
}
ensureReadSize(12, readCnt);
//version
//Frame - Type
int frameType = OssUtils.ConvertBytesToInt(buff, 1, 3);
_lastFrameType = frameType;
//Payload Length
int payloadLength = OssUtils.ConvertBytesToInt(buff, 4, 4);
//Payload Length
int headerCheckSum = OssUtils.ConvertBytesToInt(buff, 8, 4);
switch (frameType)
{
case 0x800001: //data frame
//offset
readCnt = TryRead(buff, 0, 8);
ensureReadSize(8, readCnt);
_payloadcrc32 = CRC32.GetCRC32Byte(buff, 8, 0);
//skip offset bytes
_payloadRemain = payloadLength - 8;
break;
case 0x800005: //Select object End Frame
//offset | total scanned bytes
readCnt = TryRead(buff, 0, 16);
ensureReadSize(16, readCnt);
//http status
readCnt = TryRead(buff, 0, 4);
ensureReadSize(4, readCnt);
StatusCode = OssUtils.ConvertBytesToInt(buff, 0, 4);
//error message
payloadLength = payloadLength - 20;
if (payloadLength > 0)
{
int len = Math.Min(buff.Length, payloadLength);
readCnt = TryRead(buff, 0, len);
ensureReadSize(len, readCnt);
ErrorMessage = System.Text.Encoding.Default.GetString(buff, 0, readCnt);
payloadLength -= len;
if (payloadLength > 0)
{
readCnt = TrySkip(payloadLength);
ensureReadSize(payloadLength, readCnt);
}
}
//skip payload Checksum
readCnt = TryRead(buff, 0, 4);
ensureReadSize(4, readCnt);
_gotEndFrame = true;
break;
case 0x800004: //Continuous Frame
default:
//skip playload
readCnt = TrySkip(payloadLength);
ensureReadSize(payloadLength, readCnt);
//skip payload Checksum
readCnt = TryRead(buff, 0, 4);
ensureReadSize(4, readCnt);
break;
}
}
public override CreateSelectObjectMetaResult Deserialize(ServiceResponse xmlStream)
{
var result = new CreateSelectObjectMetaResult();
var buff = new byte[128];
uint payloadCrc32 = 0;
int readCnt = 0;
bool gotEndFrame = false;
_gotEndofStream = false;
CRC32.Init();
while (!gotEndFrame)
{
//Version | Frame - Type | Payload Length | Header Checksum | Payload | Payload Checksum
//<1 bytes> <--3 bytes--> <-- 4 bytes --> <------4 bytes--> <variable><----4bytes------>
//Payload
//<offset | data>
//<8 bytes><variable>
//read Header 12 bytes
readCnt = TryRead(xmlStream.Content, buff, 0, 12);
if (_gotEndofStream)
{
break;
}
ensureReadSize(12, readCnt);
//version
//Frame - Type
int frameType = OssUtils.ConvertBytesToInt(buff, 1, 3);
//Payload Length
int payloadLength = OssUtils.ConvertBytesToInt(buff, 4, 4);
//Header Checksum
int headerCheckSum = OssUtils.ConvertBytesToInt(buff, 8, 4);
//read Playload
switch (frameType)
{
case 0x800006: //Meta End Frame(Csv)
case 0x800007: //Meta End Frame(Json)
payloadLength -= 32;
// 32 bytes
readCnt = TryRead(xmlStream.Content, buff, 0, 32);
ensureReadSize(32, readCnt);
payloadCrc32 = CRC32.GetCRC32Byte(buff, 32, payloadCrc32);
// offset 8 bytes
result.Offset = OssUtils.ConvertBytesToLong(buff, 0, 8);
// total scaned 8bytes
result.TotalScannedBytes = OssUtils.ConvertBytesToLong(buff, 8, 8);
// status 4 bytes
result.Status = OssUtils.ConvertBytesToInt(buff, 16, 4);
// splitsCount 4 bytes
result.SplitsCount = OssUtils.ConvertBytesToLong(buff, 20, 4);
// rowsCount 8 bytes
result.RowsCount = OssUtils.ConvertBytesToLong(buff, 24, 8);
// 32 bytes
if (frameType == 0x800006)
{
payloadLength -= 4;
// colsCount 4 bytes
readCnt = TryRead(xmlStream.Content, buff, 0, 4);
ensureReadSize(4, readCnt);
result.ColumnsCount = OssUtils.ConvertBytesToLong(buff, 0, 4);
payloadCrc32 = CRC32.GetCRC32Byte(buff, 4, payloadCrc32);
}
while (payloadLength > 0)
{
int len = Math.Min(buff.Length, payloadLength);
readCnt = TryRead(xmlStream.Content, buff, 0, len);
ensureReadSize(len, readCnt);
if (string.IsNullOrEmpty(result.ErrorMessage))
{
result.ErrorMessage = System.Text.Encoding.Default.GetString(buff, 0, readCnt);
}
payloadCrc32 = CRC32.GetCRC32Byte(buff, readCnt, payloadCrc32);
payloadLength -= readCnt;
}
//Payload Checksum
readCnt = TryRead(xmlStream.Content, buff, 0, 4);
ensureReadSize(4, readCnt);
uint serverCrc32 = OssUtils.ConvertBytesToUint(buff, 0, 4);
//Payload Crc32 check
if (serverCrc32 != 0 && serverCrc32 != payloadCrc32)
{
throw new ClientException(string.Format("Payload checksum check fail server CRC {0}, client CRC {1}",
serverCrc32, payloadCrc32));
}
gotEndFrame = true;
break;
default:
//skip playload
readCnt = TrySkip(xmlStream.Content, payloadLength);
ensureReadSize(payloadLength, readCnt);
//skip payload Checksum
readCnt = TryRead(xmlStream.Content, buff, 0, 4);
ensureReadSize(4, readCnt);
break;
}
}
if (!gotEndFrame)
{
throw new ClientException("No end frame exists.");
}
DeserializeGeneric(xmlStream, result);
return(result);
}
