_load

static VALUE
BigDecimal_load(VALUE self, VALUE str)
{
    ENTER(2);
    Real *pv;
    unsigned char *pch;
    unsigned char ch;
    unsigned long m=0;

    SafeStringValue(str);
    pch = (unsigned char *)RSTRING_PTR(str);
    /* First get max prec */
    while((*pch) != (unsigned char)'\0' && (ch = *pch++) != (unsigned char)':') {
        if(!ISDIGIT(ch)) {
            rb_raise(rb_eTypeError, "load failed: invalid character in the marshaled string");
        }
        m = m*10 + (unsigned long)(ch-'0');
    }
    if (m > VpBaseFig()) m -= VpBaseFig();
    GUARD_OBJ(pv, VpNewRbClass(m, (char *)pch, self));
    m /= VpBaseFig();
    if (m && pv->MaxPrec > m) {
        pv->MaxPrec = m+1;
    }
    return ToValue(pv);
}