static AsnElt BuildInteger(string iv)
{
/*
* If the string can be parsed as a 64-bit integer (signed
* or unsigned) then we can encoded it right away.
*/
long v;
if (Int64.TryParse(iv, out v))
{
return(AsnElt.MakeInteger(v));
}
ulong uv;
if (UInt64.TryParse(iv, out uv))
{
return(AsnElt.MakeInteger(uv));
}
/*
* For longer values we need ZInt.
*/
try {
ZInt z = ZInt.Parse(iv);
return(AsnElt.MakePrimitive(
AsnElt.INTEGER, z.ToBytesBE()));
} catch {
throw new IOException(
"could not convert value to integer: " + iv);
}
}
/*
* Interpret a token as a constant value (numerical constant,
* boolean, literal string). If the token is not such a constant,
* the returned value is uninitialized.
*/
internal static XValue ParseConst(string t)
{
if (t.Length == 0)
{
return(new XValue((XObject)null));
}
if (t == "true")
{
return(new XValue(XType.BOOL, 1));
}
if (t == "false")
{
return(new XValue(XType.BOOL, 0));
}
if (t[0] == '"')
{
return(new XValue(t.Substring(1)));
}
if (t[0] == '`')
{
int cp = t[1];
if (cp > 0x7F)
{
throw new Exception("non-ASCII character constant");
}
return((byte)cp);
}
bool neg = false;
if (t[0] == '+')
{
t = t.Substring(1);
}
else if (t[0] == '-')
{
neg = true;
t = t.Substring(1);
}
if (t.Length == 0 || t[0] < '0' || t[0] > '9')
{
return(new XValue((XObject)null));
}
XType bt = XType.INT;
ZInt min = Int32.MinValue;
ZInt max = Int32.MaxValue;
if (t.EndsWith("u8") || t.EndsWith("U8"))
{
t = t.Substring(0, t.Length - 2);
bt = XType.U8;
min = 0;
max = Byte.MaxValue;
}
else if (t.EndsWith("u16") || t.EndsWith("U16"))
{
t = t.Substring(0, t.Length - 3);
bt = XType.U16;
min = 0;
max = UInt16.MaxValue;
}
else if (t.EndsWith("u32") || t.EndsWith("U32"))
{
t = t.Substring(0, t.Length - 3);
bt = XType.U32;
min = 0;
max = UInt32.MaxValue;
}
else if (t.EndsWith("u64") || t.EndsWith("U64"))
{
t = t.Substring(0, t.Length - 3);
bt = XType.U64;
min = 0;
max = UInt64.MaxValue;
}
else if (t.EndsWith("i8") || t.EndsWith("I8"))
{
t = t.Substring(0, t.Length - 2);
bt = XType.I8;
min = SByte.MinValue;
max = SByte.MaxValue;
}
else if (t.EndsWith("i16") || t.EndsWith("I16"))
{
t = t.Substring(0, t.Length - 3);
bt = XType.I16;
min = Int16.MinValue;
max = Int16.MaxValue;
}
else if (t.EndsWith("i32") || t.EndsWith("I32"))
{
t = t.Substring(0, t.Length - 3);
bt = XType.I32;
min = Int32.MinValue;
max = Int32.MaxValue;
}
else if (t.EndsWith("i64") || t.EndsWith("I64"))
{
t = t.Substring(0, t.Length - 3);
bt = XType.I64;
min = Int64.MinValue;
max = Int64.MaxValue;
}
ZInt x = ZInt.Parse(t);
if (neg)
{
x = -x;
}
if (x < min || x > max)
{
throw new Exception(string.Format("value {0} is out of allowed range for type {1}", x, bt.Name));
}
return(new XValue(bt, x.ToULong));
}
