/// <summary>
/// 所有包协议一致，通过协议来检验是否为一个包
/// </summary>
/// <param name="buffer"></param>
/// <param name="offset"></param>
/// <param name="count"></param>
/// <returns></returns>
public static bool AsserIsPackage(byte[] buffer, int offset, int count)
{
//帧头，帧尾，长度判断
byte startFrame = buffer[offset];
int endFrame = buffer[count + offset - 1];
if (count < (int)SmSup.MinLength ||
(startFrame != (byte)SmFrame.Start) ||
(endFrame != (byte)SmFrame.End))
{
return(false);
}
List <byte> byList = buffer.ToList();
//固定帧校验
byte fixedFrame = byList[SmTool.GetSocketIndex(SmIndex.Fixed, offset)];
if (fixedFrame != (byte)SmFrame.Fixed)
{
return(false);
}
//crc校验
int crsFrameStart = offset + count - 3;
byte[] crcBytes = byList.GetRange(crsFrameStart, 2).ToArray().Reverse().ToArray();
int crc = BitConverter.ToUInt16(crcBytes, 0);
var crcCalc = SmCrc16.CrcCalc(buffer, offset, count - 3);
if (crc != crcCalc)
{
return(false);
}
return(true);
}
/// <summary>
/// 判断包类型，这是个辅助方法
/// </summary>
/// <param name="buffer"></param>
/// <param name="offset"></param>
/// <param name="count"></param>
/// <param name="type"></param>
/// <param name="isPackage"></param>
/// <returns></returns>
internal static bool AssertPackageType(byte[] buffer, int offset, int count, SmPackageType type, bool isPackage)
{
if (!isPackage)
{
if (!AsserIsPackage(buffer, offset, count))
{
return(false);
}
}
byte cmdFrame = buffer[SmTool.GetSocketIndex(SmIndex.Cmd, offset)];
return(cmdFrame == (byte)type);
}
/// <summary>
/// 所有包都能提取的信息
/// </summary>
/// <param name="buffer"></param>
/// <param name="offset"></param>
/// <param name="type"></param>
/// <returns></returns>
private SmModel processPackage(byte[] buffer, int offset, SmPackageType type)
{
List <byte> byList = buffer.ToList();
byList = byList.GetRange(offset, byList.Count);
var emSocket = new SmModel(type);
//解码
emSocket.ModuleAddr = byList.GetRange(SmTool.GetSocketIndex(SmIndex.MachineAddrStart), (int)SmIndex.MacineAddrCount);
emSocket.Cmd = byList[SmTool.GetSocketIndex(SmIndex.Cmd)];
emSocket.AimType = byList[SmTool.GetSocketIndex(SmIndex.AimType)];
emSocket.Buffer = buffer;
return(emSocket);
}
/// <summary>
/// 检验是否为心跳包
/// 一定要先运行AsserIsPackage
/// </summary>
/// <param name="buffer"></param>
/// <param name="offset"></param>
/// <param name="count"></param>
/// <returns></returns>
internal static bool AssertIsHeartbeatPackage(byte[] buffer, int offset, int count, bool isPackage = false)
{
if (!isPackage)
{
if (!AsserIsPackage(buffer, offset, count))
{
return(false);
}
}
byte cmdFrame = buffer[SmTool.GetSocketIndex(SmIndex.Cmd, offset)];
if (cmdFrame == (byte)SmCmdFrame.Heartbeat)
{
return(true);
}
return(false);
}
/// <summary>
/// 判断缓存中的数据是什么包
/// </summary>
/// <param name="buffer"></param>
/// <param name="offset"></param>
/// <param name="count"></param>
/// <returns></returns>
internal static SmPackageType GetPackageType(byte[] buffer, int offset, int count)
{
try {
if (AsserIsPackage(buffer, offset, count))
{
byte cmdFrame = buffer[SmTool.GetSocketIndex(SmIndex.Cmd, offset)];
if (cmdFrame == (byte)SmCmdFrame.Param)
{
return(SmPackageType.ParamPackage);
}
else if (cmdFrame == (byte)SmCmdFrame.Heartbeat)
{
return(SmPackageType.HeartbeatPackage);
}
else if (cmdFrame == (byte)SmCmdFrame.ClientReplyCmd)
{
return(SmPackageType.ClientReplyCmd);
}
}
} catch {
}
return(SmPackageType.ErrorPackage);
}