dml: Add more robust error reporting

include/ki/dml/Field.h

@@ -1,7 +1,9 @@
 #pragma once
 #include "FieldBase.h"
 #include "types.h"
+#include "exception.h"
 #include <sstream>
+#include <stdexcept>
 
 namespace ki
 {
@@ -69,7 +71,7 @@ namespace dml
 		* Example: <FieldName TYPE="STR">Value</FieldName>
 		*
 		* If the field in the XML data does not have the same type
-		* as this field, then an exception is thrown.
+		* as this field, then a value_error is thrown.
 		*/
 		void from_xml(const rapidxml::xml_node<> *node) final
 		{
@@ -82,12 +84,15 @@ namespace dml
 				attr; attr = attr->next_attribute())
 			{
 				const std::string name = attr->name();
-				if (name != "TYPE")
+				if (name == "TYPE")
 				{
 					const std::string value = attr->value();
 					if (value != get_type_name())
 					{
-						// TODO: Exceptions
+						std::ostringstream oss;
+						oss << "XML Field node has incorrect TYPE attribute value. ";
+						oss << "(value=\"" << value << "\", expected=\"" << get_type_name() << "\". ";
+						throw value_error(oss.str());
 					}
 				}
 				else if (name == "NOXFER")
@@ -97,7 +102,9 @@ namespace dml
 				}
 				else
 				{
-					// TODO: Exceptions
+					std::ostringstream oss;
+					oss << "XML Field node has unknown attribute \"" << name << "\".";
+					throw value_error(oss.str());
 				}
 			}
 
@@ -140,7 +147,11 @@ namespace dml
 			}
 			else
 			{
-				// TODO: Exceptions
+				std::ostringstream oss;
+				oss << "Tried to copy value from " <<
+					other->get_type_name() << " field to " <<
+					get_type_name() << " field.";
+				throw value_error(oss.str());
 			}
 		}
 

include/ki/dml/exception.h

@@ -0,0 +1,26 @@
+#pragma once
+#include <stdexcept>
+
+namespace ki
+{
+namespace dml
+{
+	class runtime_error : public std::runtime_error
+	{
+	public:
+		runtime_error(std::string message) : std::runtime_error(message) { }
+	};
+
+	class parse_error : public runtime_error
+	{
+	public:
+		parse_error(std::string message) : runtime_error(message) { }
+	};
+
+	class value_error : public runtime_error
+	{
+	public:
+		value_error(std::string message) : runtime_error(message) { }
+	};
+}
+}

src/dml/FieldBase.cpp

@@ -33,8 +33,9 @@ namespace dml
 		auto *type_attr = node->first_attribute("TYPE");
 		if (!type_attr)
 		{
-			// TODO: Exceptions
+			std::ostringstream oss;
-			return nullptr;
+			oss << "XML Field node is missing required TYPE attribute (" << node->name() << ").";
+			throw value_error(oss.str());
 		}
 		const std::string type = type_attr->value();
 
@@ -63,8 +64,9 @@ namespace dml
 			field = new GidField("", record);
 		else
 		{
-			// TODO: Exceptions
+			std::ostringstream oss;
-			return nullptr;
+			oss << "Unknown DML type \"" << type << "\" in XML Field node: " << node->name() << ".";
+			throw value_error(oss.str());
 		}
 
 		field->from_xml(node);

src/dml/Record.cpp

@@ -94,8 +94,9 @@ namespace dml
 		const std::string node_name = node->name();
 		if (node_name != "RECORD")
 		{
-			// TODO: Exceptions
+			std::ostringstream oss;
-			return;
+			oss << "Expected <RECORD> node but got <" << node->name() << ">.";
+			throw value_error(oss.str());
 		}
 
 		// Every child node inside a <RECORD> element is a Field.

src/dml/types/BytField.cpp

@@ -18,6 +18,12 @@ namespace dml
 	{
 		ValueBytes<BYT> data;
 		istream.read(data.buff, sizeof(BYT));
+		if (istream.fail())
+		{
+			std::ostringstream oss;
+			oss << "Not enough data was available to read BYT value (" << m_name << ").";
+			throw parse_error(oss.str());
+		}
 		m_value = data.value;
 	}
 

src/dml/types/DblField.cpp

@@ -9,24 +9,34 @@ namespace dml
 	template <>
 	void DblField::write_to(std::ostream &ostream) const
 	{
-		ValueBytes<USHRT> endianness_check;
-		endianness_check.value = 0x0102;
 		ValueBytes<DBL> data;
 		data.value = m_value;
+
+		ValueBytes<USHRT> endianness_check;
+		endianness_check.value = 0x0102;
 		if (endianness_check.buff[0] == 0x01)
 			std::reverse(&data.buff[0], &data.buff[8]);
+
 		ostream.write(data.buff, sizeof(DBL));
 	}
 
 	template <>
 	void DblField::read_from(std::istream &istream)
 	{
-		ValueBytes<USHRT> endianness_check;
-		endianness_check.value = 0x0102;
 		ValueBytes<DBL> data;
 		istream.read(data.buff, sizeof(DBL));
+		if (istream.fail())
+		{
+			std::ostringstream oss;
+			oss << "Not enough data was available to read DBL value (" << m_name << ").";
+			throw parse_error(oss.str());
+		}
+
+		ValueBytes<USHRT> endianness_check;
+		endianness_check.value = 0x0102;
 		if (endianness_check.buff[0] == 0x01)
 			std::reverse(&data.buff[0], &data.buff[8]);
+		
 		m_value = data.value;
 	}
 

src/dml/types/FltField.cpp

@@ -9,22 +9,31 @@ namespace dml
 	template <>
 	void FltField::write_to(std::ostream &ostream) const
 	{
-		ValueBytes<USHRT> endianness_check;
-		endianness_check.value = 0x0102;
 		ValueBytes<FLT> data;
 		data.value = m_value;
+
+		ValueBytes<USHRT> endianness_check;
+		endianness_check.value = 0x0102;
 		if (endianness_check.buff[0] == 0x01)
 			std::reverse(&data.buff[0], &data.buff[4]);
+		
 		ostream.write(data.buff, sizeof(FLT));
 	}
 
 	template <>
 	void FltField::read_from(std::istream &istream)
 	{
-		ValueBytes<USHRT> endianness_check;
-		endianness_check.value = 0x0102;
 		ValueBytes<FLT> data;
 		istream.read(data.buff, sizeof(FLT));
+		if (istream.fail())
+		{
+			std::ostringstream oss;
+			oss << "Not enough data was available to read FLT value (" << m_name << ").";
+			throw parse_error(oss.str());
+		}
+
+		ValueBytes<USHRT> endianness_check;
+		endianness_check.value = 0x0102;
 		if (endianness_check.buff[0] == 0x01)
 			std::reverse(&data.buff[0], &data.buff[4]);
 		m_value = data.value;

src/dml/types/GidField.cpp

@@ -19,12 +19,20 @@ namespace dml
 	template <>
 	void GidField::read_from(std::istream &istream)
 	{
-		ValueBytes<USHRT> endianness_check;
-		endianness_check.value = 0x0102;
 		ValueBytes<GID> data;
 		istream.read(data.buff, sizeof(GID));
+		if (istream.fail())
+		{
+			std::ostringstream oss;
+			oss << "Not enough data was available to read GID value (" << m_name << ").";
+			throw parse_error(oss.str());
+		}
+
+		ValueBytes<USHRT> endianness_check;
+		endianness_check.value = 0x0102;
 		if (endianness_check.buff[0] == 0x01)
 			std::reverse(&data.buff[0], &data.buff[8]);
+
 		m_value = data.value;
 	}
 

src/dml/types/IntField.cpp

@@ -19,12 +19,20 @@ namespace dml
 	template <>
 	void IntField::read_from(std::istream &istream)
 	{
-		ValueBytes<USHRT> endianness_check;
-		endianness_check.value = 0x0102;
 		ValueBytes<INT> data;
 		istream.read(data.buff, sizeof(INT));
+		if (istream.fail())
+		{
+			std::ostringstream oss;
+			oss << "Not enough data was available to read INT value (" << m_name << ").";
+			throw parse_error(oss.str());
+		}
+
+		ValueBytes<USHRT> endianness_check;
+		endianness_check.value = 0x0102;
 		if (endianness_check.buff[0] == 0x01)
 			std::reverse(&data.buff[0], &data.buff[4]);
+
 		m_value = data.value;
 	}
 

src/dml/types/ShrtField.cpp

@@ -19,12 +19,20 @@ namespace dml
 	template <>
 	void ShrtField::read_from(std::istream &istream)
 	{
-		ValueBytes<SHRT> endianness_check;
-		endianness_check.value = 0x0102;
 		ValueBytes<SHRT> data;
 		istream.read(data.buff, sizeof(SHRT));
+		if (istream.fail())
+		{
+			std::ostringstream oss;
+			oss << "Not enough data was available to read SHRT value (" << m_name << ").";
+			throw parse_error(oss.str());
+		}
+
+		ValueBytes<SHRT> endianness_check;
+		endianness_check.value = 0x0102;
 		if (endianness_check.buff[0] == 0x01)
 			std::reverse(&data.buff[0], &data.buff[2]);
+
 		m_value = data.value;
 	}
 

src/dml/types/StrField.cpp

@@ -21,16 +21,30 @@ namespace dml
 	void StrField::read_from(std::istream &istream)
 	{
 		// Get the length
-		ValueBytes<USHRT> endianness_check;
-		endianness_check.value = 0x0102;
 		ValueBytes<USHRT> length_data;
 		istream.read(length_data.buff, sizeof(USHRT));
+		if (istream.fail())
+		{
+			std::ostringstream oss;
+			oss << "Not enough data was available to read STR value (" << m_name << ").";
+			throw parse_error(oss.str());
+		}
+
+		ValueBytes<USHRT> endianness_check;
+		endianness_check.value = 0x0102;
 		if (endianness_check.buff[0] == 0x01)
 			std::reverse(&length_data.buff[0], &length_data.buff[2]);
 
 		// Read the data into a buffer
 		char *data = new char[length_data.value + 1] { 0 };
 		istream.read(data, length_data.value);
+		if (istream.fail())
+		{
+			std::ostringstream oss;
+			oss << "Not enough data was available to read STR value (" << m_name << ").";
+			throw parse_error(oss.str());
+		}
+
 		m_value = STR(data);
 		delete[] data;
 	}

src/dml/types/UBytField.cpp

@@ -18,6 +18,12 @@ namespace dml
 	{
 		ValueBytes<UBYT> data;
 		istream.read(data.buff, sizeof(UBYT));
+		if (istream.fail())
+		{
+			std::ostringstream oss;
+			oss << "Not enough data was available to read UBYT value (" << m_name << ").";
+			throw parse_error(oss.str());
+		}
 		m_value = data.value;
 	}
 

src/dml/types/UIntField.cpp

@@ -19,12 +19,20 @@ namespace dml
 	template <>
 	void UIntField::read_from(std::istream &istream)
 	{
-		ValueBytes<USHRT> endianness_check;
-		endianness_check.value = 0x0102;
 		ValueBytes<UINT> data;
 		istream.read(data.buff, sizeof(UINT));
+		if (istream.fail())
+		{
+			std::ostringstream oss;
+			oss << "Not enough data was available to read UINT value (" << m_name << ").";
+			throw parse_error(oss.str());
+		}
+
+		ValueBytes<USHRT> endianness_check;
+		endianness_check.value = 0x0102;
 		if (endianness_check.buff[0] == 0x01)
 			std::reverse(&data.buff[0], &data.buff[4]);
+
 		m_value = data.value;
 	}
 

src/dml/types/UShrtField.cpp

@@ -23,6 +23,13 @@ namespace dml
 		endianness_check.value = 0x0102;
 		ValueBytes<USHRT> data;
 		istream.read(data.buff, sizeof(USHRT));
+		if (istream.fail())
+		{
+			std::ostringstream oss;
+			oss << "Not enough data was available to read USHRT value (" << m_name << ").";
+			throw parse_error(oss.str());
+		}
+
 		if (endianness_check.buff[0] == 0x01)
 			std::reverse(&data.buff[0], &data.buff[2]);
 		m_value = data.value;

src/dml/types/WStrField.cpp

@@ -23,10 +23,17 @@ namespace dml
 	void WStrField::read_from(std::istream &istream)
 	{
 		// Get the length
-		ValueBytes<USHRT> endianness_check;
-		endianness_check.value = 0x0102;
 		ValueBytes<USHRT> length_data;
 		istream.read(length_data.buff, sizeof(USHRT));
+		if (istream.fail())
+		{
+			std::ostringstream oss;
+			oss << "Not enough data was available to read WSTR value (" << m_name << ").";
+			throw parse_error(oss.str());
+		}
+
+		ValueBytes<USHRT> endianness_check;
+		endianness_check.value = 0x0102;
 		if (endianness_check.buff[0] == 0x01)
 			std::reverse(&length_data.buff[0], &length_data.buff[2]);
 
@@ -34,11 +41,21 @@ namespace dml
 		size_t length = length_data.value * sizeof(char16_t);
 		char *data = new char[length + sizeof(char16_t)]{ 0 };
 		istream.read(data, length);
+		if (istream.fail())
+		{
+			std::ostringstream oss;
+			oss << "Not enough data was available to read WSTR value (" << m_name << ").";
+			throw parse_error(oss.str());
+		}
+
+		// Reverse each character from little endian to big endian
+		// if memory is supposed to be in big endian on this PC.
 		for (int i = 0; i < length; i += 2)
 		{
 			if (endianness_check.buff[0] == 0x01)
 				std::reverse(&data[i], &data[i + 2]);
 		}
+
 		m_value = WSTR((char16_t *)data);
 		delete[] data;
 	}