cnet's Application Programming Interface

NAME

CRC and checksum functions

SYNOPSIS

#include <cnet.h> int32_t CNET_IP_checksum(unsigned short *addr, size_t nbytes); uint16_t CNET_ccitt(unsigned char *addr, size_t nbytes); uint16_t CNET_crc16(unsigned char *addr, size_t nbytes); uint32_t CNET_crc32(unsigned char *addr, size_t nbytes);

DESCRIPTION

These four functions each take a memory address and perform the requested checksum (iff CNET_IP_checksum()) or CRC (the other three) calculation on the indicated number of bytes starting from that address.

CNET_IP_checksum() calculates the standard Internet checksum, as defined in RFC-1071.

RETURN VALUE

The value returned will be the requested CRC or checksum of the indicated block of memory. No error detection is performed on the arguments.