fixed getNextOffset() and added optional PartType argument, renamed pt_template to pt_any, added getPartType()

src/lib/ebus/data.cpp

@@ -165,7 +165,7 @@ result_t DataField::create(std::vector<std::string>::iterator& it,
 				posStr++;
 		}
 		else if (isTemplate) {
-			partType = pt_template;
+			partType = pt_any;
 		}
 		else {
 			result = RESULT_ERR_INVALID_ARG;
@@ -174,7 +174,7 @@ result_t DataField::create(std::vector<std::string>::iterator& it,
 
 		if (posStr[0] == 0) {
 			if (fields.empty() == false)
-				offset = fields.back()->getNextOffset();
+				offset = fields.back()->getNextOffset(partType);
 			else
 				offset = 0;
 			length = 0;
@@ -274,7 +274,7 @@ result_t DataField::create(std::vector<std::string>::iterator& it,
 				result = ref->second->derive(name, comment, unit, partType, offset, divisor, values, fields);
 				if (result != RESULT_OK)
 					break;
-				offset = fields.back()->getNextOffset();
+				offset = fields.back()->getNextOffset(partType);
 			}
 			if (offset > MAX_POS) {
 				result = RESULT_ERR_INVALID_ARG; // invalid pos definition
@@ -362,8 +362,11 @@ result_t DataField::create(std::vector<std::string>::iterator& it,
 }
 
 
-unsigned char SingleDataField::getNextOffset()
+unsigned char SingleDataField::getNextOffset(PartType partType)
 {
+	if (partType != pt_any && partType != m_partType)
+		return 0;
+
 	unsigned char offset = m_offset + m_length;
 	if ((m_dataType.numBits % 8) != 0
 			&& m_dataType.precisionOrFirstBit + (m_dataType.numBits % 8) < 8)
@@ -429,7 +432,7 @@ result_t StringDataField::derive(std::string name, std::string comment,
 		unsigned int divisor, std::map<unsigned int, std::string> values,
 		std::vector<SingleDataField*>& fields)
 {
-	if (m_partType != pt_template && partType == pt_template)
+	if (m_partType != pt_any && partType == pt_any)
 		return RESULT_ERR_INVALID_ARG; // cannot create a template from a concrete instance
 	if (divisor != 0 || values.empty() == false)
 		return RESULT_ERR_INVALID_ARG; // cannot set divisor or values for string field
@@ -706,7 +709,7 @@ result_t NumberDataField::derive(std::string name, std::string comment,
 		unsigned int divisor, std::map<unsigned int, std::string> values,
 		std::vector<SingleDataField*>& fields)
 {
-	if (m_partType != pt_template && partType == pt_template)
+	if (m_partType != pt_any && partType == pt_any)
 		return RESULT_ERR_INVALID_ARG; // cannot create a template from a concrete instance
 	if (name.empty() == true)
 		name = m_name;
@@ -840,7 +843,7 @@ result_t ValueListDataField::derive(std::string name, std::string comment,
 		unsigned int divisor, std::map<unsigned int, std::string> values,
 		std::vector<SingleDataField*>& fields)
 {
-	if (m_partType != pt_template && partType == pt_template)
+	if (m_partType != pt_any && partType == pt_any)
 		return RESULT_ERR_INVALID_ARG; // cannot create a template from a concrete instance
 	if (name.empty() == true)
 		name = m_name;
@@ -911,9 +914,17 @@ DataFieldSet::~DataFieldSet()
 	}
 }
 
-unsigned char DataFieldSet::getNextOffset()
+unsigned char DataFieldSet::getNextOffset(PartType partType)
 {
-	return m_fields.back()->getNextOffset();
+		return 0;
+
+	for (std::vector<SingleDataField*>::reverse_iterator it = m_fields.rbegin(); it < m_fields.rend(); it++) {
+		SingleDataField* field = *it;
+		if (partType == pt_any || partType == field->getPartType())
+			return field->getNextOffset(partType);
+	}
+
+	return 0;
 }
 
 result_t DataFieldSet::derive(std::string name, std::string comment,

src/lib/ebus/data.h

@@ -28,7 +28,7 @@
 
 /** the message part in which a data field is stored. */
 enum PartType {
-	pt_template,   // special part type for templates (relative offset)
+	pt_any,        // stored in any data (master or slave, relative offset)
 	pt_masterData, // stored in master data
 	pt_slaveData,  // stored in slave data
 	};
@@ -112,9 +112,10 @@ public:
 			const bool isSetMessage=false, const unsigned char dstAddress=SYN);
 	/**
 	 * @brief Returns the offset to the first symbol in the message part for a field following this field.
+	 * @param partType the message part for which to get the offset, or @a pt_any for any.
 	 * @return the offset to the first symbol in the message part for a field following this field.
 	 */
-	virtual unsigned char getNextOffset() = 0;
+	virtual unsigned char getNextOffset(PartType partType=pt_any) = 0;
 	/**
 	 * @brief Derives a new DataField from this field.
 	 * @param name the field name.
@@ -134,12 +135,12 @@ public:
 	 * @brief Get the field name.
 	 * @return the field name.
 	 */
-	const std::string getName() { return m_name; }
+	std::string getName() const { return m_name; }
 	/**
 	 * @brief Get the field comment.
 	 * @return the field comment.
 	 */
-	const std::string getComment() { return m_comment; }
+	std::string getComment() const { return m_comment; }
 	/**
 	 * @brief Reads the value from the master or slave @a SymbolString.
 	 * @param masterData the unescaped master data @a SymbolString for reading binary data.
@@ -204,9 +205,14 @@ public:
 	 * @brief Get the value unit.
 	 * @return the value unit.
 	 */
-	const std::string getUnit() { return m_unit; }
+	std::string getUnit() const { return m_unit; }
+	/**
+	 * @brief Get the message part in which the field is stored.
+	 * @return the message part in which the field is stored.
+	 */
+	PartType getPartType() const { return m_partType; }
 	// @copydoc
-	virtual unsigned char getNextOffset();
+	virtual unsigned char getNextOffset(PartType partType=pt_any);
 	/**
 	 * @brief Reads the value from the master or slave @a SymbolString.
 	 * @param masterData the unescaped master data @a SymbolString for reading binary data.
@@ -470,7 +476,7 @@ public:
 	 */
 	virtual ~DataFieldSet();
 	// @copydoc
-	virtual unsigned char getNextOffset();
+	virtual unsigned char getNextOffset(PartType partType=pt_any);
 	// @copydoc
 	virtual result_t derive(std::string name, std::string comment,
 			std::string unit, const PartType partType, unsigned char offset,