///////////////////////////
//receive byte Array via XModem using either Checksum or CRC error detection
/// ///////////////////////
public byte[] XModemReceive(bool useCRC, XModemHandler stop)
{
//since we don't know how many bytes we receive it's the
//best solution to use a MemoryStream
System.IO.MemoryStream buf = new System.IO.MemoryStream();
int packetno = 1;
int retry = 0;
int i, c;
double kb = 0;
if (useCRC) // send and use CRC
{
this.writeByte(C);
}
else //send and don't use CRC
{
this.writeByte(NAK);
}
while (retry < 16)
{
try {
c = port.ReadByte();
}
catch {
c = 0x00;
}
if (c == SOH || c == STX)
{
#region SOH/STX
retry = 0;
bufsz = 128; // default buffer size
if (c == STX)
{
bufsz = 1024; // buffer size for Xmodem1K
}
#region fill packet with datastream
xbuff[0] = (byte)c;
for (i = 0; i < (bufsz + (useCRC ? 1 : 0) + 3); i++)
{
xbuff[i + 1] = (byte)this.port.ReadByte();
}
#endregion
if (stop.IsCanceled)
{
break;
}
if (xbuff[1] == (byte)(~xbuff[2]) && xbuff[1] == packetno && check(useCRC, xbuff, 3, bufsz))
{
//add buffer to memory stream
buf.Write(xbuff, 3, bufsz);
this.writeByte(ACK);
#region fire event & increment packet number
//128 or 1024 Byte per package
double d = bufsz;
d = d / 1024;
kb = (kb + d);
if (this.PacketReceived != null)
{
PacketReceived(this, null);
}
packetno++;
if (packetno >= 256)
{
packetno = 0;
}
#endregion
}
else
{
this.writeByte(NAK);
}
#endregion
}
else if (c == EOT)
{
#region EOT
port.DiscardInBuffer();
this.writeByte(ACK);
//convert from memory stream to byte[]
return(buf.ToArray());
#endregion
}
else if (c == CAN)
{
#region CAN
if (port.ReadByte() == CAN)
{
port.DiscardInBuffer();
this.writeByte(ACK);
return(null); //canceled by remote
}
#endregion
}
else
{
retry++;
port.DiscardInBuffer();
this.writeByte(NAK);
}
}//while()
//timeout
this.writeByte(CAN);
this.writeByte(CAN);
this.writeByte(CAN);
port.DiscardInBuffer();
return(null);
}
///////////////////////////
//receive byte Array via XModem using either Checksum or CRC error detection
/// ///////////////////////
public byte[] XModemReceive(bool useCRC, XModemHandler stop)
{
//since we don't know how many bytes we receive it's the
//best solution to use a MemoryStream
System.IO.MemoryStream buf = new System.IO.MemoryStream();
int packetno = 1;
int retry = 0;
int i, c;
double kb = 0;
if (useCRC) // send and use CRC
this.writeByte(C);
else //send and don't use CRC
this.writeByte(NAK);
while (retry < 16)
{
try {
c = port.ReadByte();
}
catch {
c = 0x00;
}
if (c == SOH || c == STX)
{
#region SOH/STX
retry = 0;
bufsz = 128; // default buffer size
if (c == STX)
bufsz = 1024; // buffer size for Xmodem1K
#region fill packet with datastream
xbuff[0] = (byte)c;
for (i = 0; i < (bufsz + (useCRC ? 1 : 0) + 3); i++)
{
xbuff[i + 1] = (byte)this.port.ReadByte();
}
#endregion
if (stop.IsCanceled) {
break;
}
if (xbuff[1] == (byte)(~xbuff[2]) && xbuff[1] == packetno && check(useCRC, xbuff, 3, bufsz))
{
//add buffer to memory stream
buf.Write(xbuff, 3, bufsz);
this.writeByte(ACK);
#region fire event & increment packet number
//128 or 1024 Byte per package
double d = bufsz;
d = d / 1024;
kb = (kb + d);
if (this.PacketReceived != null)
PacketReceived(this, null);
packetno++;
if (packetno >= 256)
packetno = 0;
#endregion
}
else
{
this.writeByte(NAK);
}
#endregion
}
else if (c == EOT)
{
#region EOT
port.DiscardInBuffer();
this.writeByte(ACK);
//convert from memory stream to byte[]
return buf.ToArray();
#endregion
}
else if (c == CAN)
{
#region CAN
if (port.ReadByte() == CAN)
{
port.DiscardInBuffer();
this.writeByte(ACK);
return null; //canceled by remote
}
#endregion
}
else
{
retry++;
port.DiscardInBuffer();
this.writeByte(NAK);
}
}//while()
//timeout
this.writeByte(CAN);
this.writeByte(CAN);
this.writeByte(CAN);
port.DiscardInBuffer();
return null;
}