checksums.c

#include "main-header.h"
long crc32(void *adr, int size) {
  const uint8_t *bbuf = adr;
 
  int i;
  uint32_t crc = 0;
 
  for (i = 0; i < size; i++) {
    crc = crc + bbuf[i];
  }
  crc = 0xFFFFFFFF - crc;
  return crc;
}
 
uint32_t calc_crc32(uint8_t *buf, int len, int chksumoffset) {
  int i;
  uint32_t crc = 0;
 
  for (i = 0; i < len; i++) {
    if ((chksumoffset >= 0) && (i >= chksumoffset) && (i <= chksumoffset + 3)) {
      continue;
    }
    crc = crc + buf[i];
  }
  crc = 0xFFFFFFFF - crc;
  return crc;
}