PULL4
#define PULL8(p) (PULL4(p)+((off_t)PULL4(p+4)<<32))
log->ccrc = PULL4(buf + HEAD + 16);
log->clen = PULL4(buf + HEAD + 20);
log->tcrc = PULL4(buf + HEAD + 24);
log->tlen = PULL4(buf + HEAD + 28);