private void AddULong(uint ulAdd)
{
ulong dwlAccum = ulAdd;
int iData; // which UI4 in this we are on
int iDataMax = _bLen; // # of UI4s in this
uint[] rguiData = new uint[4] { _data1, _data2, _data3, _data4 };
// Add, starting at the LS UI4 until out of UI4s or no carry
iData = 0;
do
{
dwlAccum += rguiData[iData];
rguiData[iData] = (uint)dwlAccum; // equivalent to mod x_dwlBaseUI4
dwlAccum >>= 32; // equivalent to dwlAccum /= x_dwlBaseUI4;
if (0 == dwlAccum)
{
StoreFromWorkingArray(rguiData);
return;
}
iData++;
}
while (iData < iDataMax);
// There is carry at the end
Debug.Assert(dwlAccum < s_ulInt32Base, "dwlAccum < x_lInt32Base", "");
// Either overflowed
if (iData == s_cNumeMax)
throw new OverflowException(SQLResource.s_arithOverflowMessage);
// Or need to extend length by 1 UI4
rguiData[iData] = (uint)dwlAccum;
_bLen++;
if (FGt10_38(rguiData))
throw new OverflowException(SQLResource.s_arithOverflowMessage);
StoreFromWorkingArray(rguiData);
}
private static SqlDecimal Round(SqlDecimal n, int lPosition, bool fTruncate) { if (n.IsNull) return SqlDecimal.Null; if (lPosition >= 0) { //If round to the right of decimal number lPosition = Math.Min(s_NUMERIC_MAX_PRECISION, lPosition); if (lPosition >= n.m_bScale) return n; //No need to round } else { //If round to the left of the decimal point lPosition = Math.Max(-s_NUMERIC_MAX_PRECISION, lPosition); //Return +0.00 if truncation of integer part if (lPosition < n.m_bScale - n.m_bPrec) { n.SetToZero(); return n; } } uint ulRem = 0; // Remainder: the highest significant digit to be truncated int lAdjust = Math.Abs(lPosition - (int)n.m_bScale); // Precision adjustment uint ulLastDivBase = 1; // //Compute the integral part of the numeric while (lAdjust > 0) { if (lAdjust >= 9) { ulRem = n.DivByULong(s_rgulShiftBase[8]); ulLastDivBase = s_rgulShiftBase[8]; lAdjust -= 9; } else { ulRem = n.DivByULong(s_rgulShiftBase[lAdjust - 1]); ulLastDivBase = s_rgulShiftBase[lAdjust - 1]; lAdjust = 0; } } // The rounding only depends on the first digit after the rounding position if (ulLastDivBase > 1) { ulRem /= (ulLastDivBase / 10); } //If result is zero, return if (n.FZero() && (fTruncate || ulRem < 5)) { n.SetPositive(); n.AssertValid(); return n; } // Adjust by adding 1 if remainder is larger than 5 if (ulRem >= 5 && !fTruncate) n.AddULong(1); // Convert back to original scale lAdjust = Math.Abs(lPosition - n.m_bScale); while (lAdjust-- > 0) { n.MultByULong(s_ulBase10); } n.AssertValid(); return n; }