From a24e61fddaf09d2989fff25785e329454c842d7f Mon Sep 17 00:00:00 2001 From: Mattijs Korpershoek Date: Wed, 14 May 2014 11:58:21 +0200 Subject: FixedPointParameter: Rename conversion functions BZ: 197723 Give a few functions more meaningful names. Add some cast fixes and doxygen to the renamed functions. Change-Id: I002a3fa9b397294153c23b9883c3ad3b1c136e54 Signed-off-by: Mattijs Korpershoek --- parameter/FixedPointParameterType.cpp | 24 ++++++++++++------------ parameter/FixedPointParameterType.h | 28 ++++++++++++++++++++++------ 2 files changed, 34 insertions(+), 18 deletions(-) diff --git a/parameter/FixedPointParameterType.cpp b/parameter/FixedPointParameterType.cpp index d465ace..c9f736f 100644 --- a/parameter/FixedPointParameterType.cpp +++ b/parameter/FixedPointParameterType.cpp @@ -131,7 +131,7 @@ bool CFixedPointParameterType::toBlackboard(const string& strValue, uint32_t& ui } return convertFromDecimal(strValue, uiValue, parameterAccessContext); } - return convertFromQiQf(strValue, uiValue, parameterAccessContext); + return convertFromQnm(strValue, uiValue, parameterAccessContext); } void CFixedPointParameterType::setOutOfRangeError(const string& strValue, CParameterAccessContext& parameterAccessContext) const @@ -208,7 +208,7 @@ bool CFixedPointParameterType::fromBlackboard(string& strValue, const uint32_t& signExtend(iData); // Conversion - double dData = asDouble(iData); + double dData = binaryQnmToDouble(iData); strStream << fixed << setprecision(_uiFractional) << dData; } @@ -231,7 +231,7 @@ bool CFixedPointParameterType::toBlackboard(double dUserValue, uint32_t& uiValue } // Do the conversion - int32_t iData = asInteger(dUserValue); + int32_t iData = doubleToBinaryQnm(dUserValue); // Check integrity assert(isEncodable((uint32_t)iData, true)); @@ -253,7 +253,7 @@ bool CFixedPointParameterType::fromBlackboard(double& dUserValue, uint32_t uiVal // Sign extend signExtend(iData); - dUserValue = asDouble(iData); + dUserValue = binaryQnmToDouble(iData); return true; } @@ -308,7 +308,8 @@ bool CFixedPointParameterType::convertFromDecimal(const string& strValue, uint32 return true; } -bool CFixedPointParameterType::convertFromQiQf(const string& strValue, uint32_t& uiValue, CParameterAccessContext& parameterAccessContext) const +bool CFixedPointParameterType::convertFromQnm(const string& strValue, uint32_t& uiValue, + CParameterAccessContext& parameterAccessContext) const { double dData; @@ -317,7 +318,7 @@ bool CFixedPointParameterType::convertFromQiQf(const string& strValue, uint32_t& setOutOfRangeError(strValue, parameterAccessContext); return false; } - uiValue = static_cast(asInteger(dData)); + uiValue = static_cast(doubleToBinaryQnm(dData)); // check that the data is encodable and has been safely written to the blackboard assert(isEncodable(uiValue, true)); @@ -336,11 +337,10 @@ bool CFixedPointParameterType::checkValueAgainstRange(double dValue) const } // Data conversion -int32_t CFixedPointParameterType::asInteger(double dValue) const +int32_t CFixedPointParameterType::doubleToBinaryQnm(double dValue) const { - // Do the conversion // For Qn.m number, multiply by 2^n and round to the nearest integer - int32_t iData = (int32_t)(round(dValue * (1UL << _uiFractional))); + int32_t iData = static_cast(round(dValue * (1UL << _uiFractional))); // Left justify // For a Qn.m number, shift 32 - (n + m + 1) bits to the left (the rest of // the bits aren't used) @@ -349,12 +349,12 @@ int32_t CFixedPointParameterType::asInteger(double dValue) const return iData; } -double CFixedPointParameterType::asDouble(int32_t iValue) const + +double CFixedPointParameterType::binaryQnmToDouble(int32_t iValue) const { // Unjustify iValue >>= getSize() * 8 - getUtilSizeInBits(); - // Convert - return (double)iValue / (1UL << _uiFractional); + return static_cast(iValue) / (1UL << _uiFractional); } // From IXmlSource diff --git a/parameter/FixedPointParameterType.h b/parameter/FixedPointParameterType.h index acb638a..3ef53eb 100644 --- a/parameter/FixedPointParameterType.h +++ b/parameter/FixedPointParameterType.h @@ -104,18 +104,18 @@ private: bool convertFromHexadecimal(const string& strValue, uint32_t& uiValue, CParameterAccessContext& parameterAccessContext) const; /** - * Convert a QI QF represented string into an unsigned long integer. + * Convert a Qn.m represented string into an unsigned long integer. * In case of a failing conversion or encodability, this function set the error to * illegal value provided and gives the range allowed for the parameter. * - * @param[in] strValue Parameter read from the XML file representated as a string in QIQF + * @param[in] strValue Parameter read from the XML file representated as a string in Qn.m * representation. * @param[out] uiValue Parameter representated as a long unsigned integer. * @param[in:out] parameterAccessContext Parameter access context. * * @return true if the string was successfully converted, false otherwise. */ - bool convertFromQiQf(const string& strValue, uint32_t& uiValue, CParameterAccessContext& parameterAccessContext) const; + bool convertFromQnm(const string& strValue, uint32_t& uiValue, CParameterAccessContext& parameterAccessContext) const; /** * Set the out of range error. @@ -129,9 +129,25 @@ private: // Check if data is encodable bool checkValueAgainstRange(double dValue) const; - // Data conversion - int32_t asInteger(double dValue) const; - double asDouble(int32_t iValue) const; + + /** + * Convert a double towards a Qn.m representation which is stored in binary format. + * This value is rounded if the double is not encodable in the corresponding Qn.m format. + * + * @param[in] dValue the double which should be converted. + * + * @return the integer which contains the converted Qn.m number. + */ + int32_t doubleToBinaryQnm(double dValue) const; + + /** + * Convert a Qn.m binary number towards its double representation. + * + * @param[in] iValue the integer which contains the Qn.m number which should be converted. + * + * @return the double which contains the double representation of iValue. + */ + double binaryQnmToDouble(int32_t iValue) const; // Integral part in Q notation uint32_t _uiIntegral; -- cgit v1.1