Need HELP to calculate Checksum/CRC for a structure! [Urgent Please]
Hi Mates,
Code:
struct R_Data
{
unsigned short id;
unsigned char flag;
float value;
time_t time_stamp;
}
struct R_Packet
{
struct R_Data packet[100]; // 100 R_Data packets
unsigned int header; // Sequence number of packet (i.e; For 1st R_Packet variable, header=1, For 2nd R_Packet variable, header=2 ...)
unsigned int footer; // will be reserved for checksum/CRC verification at client side
};
My task is Sending 600 R_Data structures to the client by packing 100 R_Data structure variables into 1 packet (Structure R_Packet). So, Total 6 R_Packet will be sent from server to client via TCP Stream socket. As i said sequence number of each R_Packet will be stored in its header variable and Footer variable is reserved/used for storing the Checksum.
I need your help for the implemntation/calculation of checksum or CRC for each R_Packet before sending and the checksum/CRC result will be stored in R_Packet.footer which will be used by client to verify the packet loss.
My Question is:
How to calculate the Checksum on this heterogenous type packet?
Any standard algorithms are there?
If u have any readymade checksum Code, Please Share!
I desperately Need your help!
Thanks and Regards,
Sravan Kumar.