#include <vector>
#include <string>
+#include <iostream>
+#include <sstream>
+
+#include <boost/utility.hpp>
#if PROPS_STANDALONE
#else
#include <simgear/structure/SGReferenced.hxx>
#include <simgear/structure/SGSharedPtr.hxx>
+// XXX This whole file should be in the simgear namespace, but I don't
+// have the guts yet...
+
+namespace simgear
+{
+template<typename T>
+std::istream& readFrom(std::istream& stream, T& result)
+{
+ stream >> result;
+ return stream;
+}
+
+/**
+ * Parse a string as an object of a given type.
+ * XXX no error behavior yet.
+ *
+ * @tparam T the return type
+ * @param str the string
+ * @return the object.
+ */
+template<typename T>
+inline T parseString(const std::string& str)
+{
+ std::istringstream stream(str);
+ T result;
+ readFrom(stream, result);
+ return result;
+}
+
+/**
+ * Property value types.
+ */
#ifdef NONE
#pragma warn A sloppy coder has defined NONE as a macro!
#undef STRING
#endif
+namespace props
+{
+/**
+ * The possible types of an SGPropertyNode. Types that appear after
+ * EXTENDED are not stored in the SGPropertyNode itself.
+ */
+enum Type {
+ NONE = 0, /**< The node hasn't been assigned a value yet. */
+ ALIAS, /**< The node "points" to another node. */
+ BOOL,
+ INT,
+ LONG,
+ FLOAT,
+ DOUBLE,
+ STRING,
+ UNSPECIFIED,
+ EXTENDED /**< The node's value is not stored in the property;
+ * the actual value and type is retrieved from an
+ * SGRawValue node. This type is never returned by @see
+ * SGPropertyNode::getType.
+ */
+};
+
+template<typename T> struct PropertyTraits;
+
+#define DEFINTERNALPROP(TYPE, PROP) \
+template<> \
+struct PropertyTraits<TYPE> \
+{ \
+ static const Type type_tag = PROP; \
+ enum { Internal = 1 }; \
+}
+
+DEFINTERNALPROP(bool, BOOL);
+DEFINTERNALPROP(int, INT);
+DEFINTERNALPROP(long, LONG);
+DEFINTERNALPROP(float, FLOAT);
+DEFINTERNALPROP(double, DOUBLE);
+DEFINTERNALPROP(const char *, STRING);
+#undef DEFINTERNALPROP
+
+}
+}
+
+
\f
////////////////////////////////////////////////////////////////////////
// a small performance hit for that.
////////////////////////////////////////////////////////////////////////
+/**
+ * Base class for SGRawValue classes that holds no type
+ * information. This allows some generic manipulation of the
+ * SGRawValue object.
+ */
+class SGRaw
+{
+public:
+ /**
+ * Get the type enumeration for the raw value.
+ *
+ * @return the type.
+ */
+ virtual simgear::props::Type getType() const = 0;
+ virtual ~SGRaw() {}
+
+ /**
+ * Create a new deep copy of this raw value.
+ *
+ * The copy will contain its own version of the underlying value
+ * as well, and will be the same type.
+ *
+ * @return A deep copy of the current object.
+ */
+ virtual SGRaw* clone() const = 0;
+
+};
+
+class SGRawExtended : public SGRaw
+{
+public:
+ /**
+ * Make an SGRawValueContainer from the SGRawValue.
+ *
+ * This is a virtual function of SGRawExtended so that
+ * SGPropertyNode::untie doesn't need to know the type of an
+ * extended property.
+ */
+ virtual SGRawExtended* makeContainer() const = 0;
+ /**
+ * Write value out to a stream
+ */
+ virtual std::ostream& printOn(std::ostream& stream) const = 0;
+ /**
+ * Read value from a stream and store it.
+ */
+ virtual std::istream& readFrom(std::istream& stream) = 0;
+};
+
+// Choose between different base classes based on whether the value is
+// stored internal to the property node. This frees us from defining
+// the virtual functions in the SGRawExtended interface where they
+// don't make sense, e.g. readFrom for the const char* type.
+template<typename T, int internal = simgear::props::PropertyTraits<T>::Internal>
+class SGRawBase;
+
+template<typename T>
+class SGRawBase<T, 1> : public SGRaw
+{
+};
+
+template<typename T>
+class SGRawBase<T, 0> : public SGRawExtended
+{
+ virtual SGRawExtended* makeContainer() const;
+ virtual std::ostream& printOn(std::ostream& stream) const;
+ virtual std::istream& readFrom(std::istream& stream);
+};
/**
* Abstract base class for a raw value.
* set, and clone the underlying value. The SGRawValue may change
* frequently during a session as a value is retyped or bound and
* unbound to various data source, but the abstract SGPropertyNode
- * layer insulates the application from those changes. The raw value
- * contains no facilities for data binding or for type conversion: it
- * is simply the abstraction of a primitive data type (or a compound
- * data type, in the case of a string).</p>
+ * layer insulates the application from those changes.
*
* <p>The SGPropertyNode class always keeps a *copy* of a raw value,
* not the original one passed to it; if you override a derived class
* @see SGRawValueFunctionsIndexed
* @see SGRawValueMethods
* @see SGRawValueMethodsIndexed
+ * @see SGRawValueContainer
*/
template <class T>
-class SGRawValue
+class SGRawValue : public SGRawBase<T>
{
public:
/**
- * Create a new deep copy of this raw value.
- *
- * The copy will contain its own version of the underlying value
- * as well.
- *
- * @return A deep copy of the current object.
+ * Return the type tag for this raw value type.
*/
- virtual SGRawValue * clone () const = 0;
+ virtual simgear::props::Type getType() const
+ {
+ return simgear::props::PropertyTraits<T>::type_tag;
+ }
};
+
+////////////////////////////////////////////////////////////////////////
+// Default values for every type.
+////////////////////////////////////////////////////////////////////////
+
+template<> const bool SGRawValue<bool>::DefaultValue;
+template<> const int SGRawValue<int>::DefaultValue;
+template<> const long SGRawValue<long>::DefaultValue;
+template<> const float SGRawValue<float>::DefaultValue;
+template<> const double SGRawValue<double>::DefaultValue;
+template<> const char * const SGRawValue<const char *>::DefaultValue;
+
/**
* A raw value bound to a pointer.
*
*
* The copy will use the same external pointer as the original.
*/
- virtual SGRawValue<T> * clone () const {
- return new SGRawValuePointer<T>(_ptr);
+ virtual SGRaw* clone () const {
+ return new SGRawValuePointer(_ptr);
}
private:
/**
* Create a copy of this raw value, bound to the same functions.
*/
- virtual SGRawValue<T> * clone () const {
- return new SGRawValueFunctions<T>(_getter,_setter);
+ virtual SGRaw* clone () const {
+ return new SGRawValueFunctions(_getter,_setter);
}
private:
if (_setter) { (*_setter)(_index, value); return true; }
else return false;
}
- virtual SGRawValue<T> * clone () const {
- return new SGRawValueFunctionsIndexed<T>(_index, _getter, _setter);
+ virtual SGRaw* clone () const {
+ return new SGRawValueFunctionsIndexed(_index, _getter, _setter);
}
private:
int _index;
if (_setter) { (_obj.*_setter)(value); return true; }
else return false;
}
- virtual SGRawValue<T> * clone () const {
- return new SGRawValueMethods<C,T>(_obj, _getter, _setter);
+ virtual SGRaw* clone () const {
+ return new SGRawValueMethods(_obj, _getter, _setter);
}
private:
C &_obj;
if (_setter) { (_obj.*_setter)(_index, value); return true; }
else return false;
}
- virtual SGRawValue<T> * clone () const {
- return new SGRawValueMethodsIndexed<C,T>(_obj, _index, _getter, _setter);
+ virtual SGRaw* clone () const {
+ return new SGRawValueMethodsIndexed(_obj, _index, _getter, _setter);
}
private:
C &_obj;
setter_t _setter;
};
+/**
+ * A raw value that contains its value. This provides a way for
+ * property nodes to contain values that shouldn't be stored in the
+ * property node itself.
+ */
+template <class T>
+class SGRawValueContainer : public SGRawValue<T>
+{
+public:
+
+ /**
+ * Explicit constructor.
+ */
+ SGRawValueContainer(const T& obj) : _obj(obj) {}
+
+ /**
+ * Destructor.
+ */
+ virtual ~SGRawValueContainer() {}
+
+ /**
+ * Get the underlying value.
+ */
+ virtual T getValue() const { return _obj; }
+
+ /**
+ * Set the underlying value.
+ *
+ * This method will dereference the pointer and change the
+ * variable's value.
+ */
+ virtual bool setValue (T value) { _obj = value; return true; }
+
+ /**
+ * Create a copy of this raw value.
+ */
+ virtual SGRaw* clone () const {
+ return new SGRawValueContainer(_obj);
+ }
+
+private:
+ T _obj;
+};
+
+template<typename T>
+SGRawExtended* SGRawBase<T, 0>::makeContainer() const
+{
+ return new SGRawValueContainer<T>(static_cast<const SGRawValue<T>*>(this)
+ ->getValue());
+}
+
+template<typename T>
+std::ostream& SGRawBase<T, 0>::printOn(std::ostream& stream) const
+{
+ return stream << static_cast<SGRawValue<T>*>(this)->getValue();
+}
+
+template<typename T>
+std::istream& SGRawBase<T, 0>::readFrom(std::istream& stream)
+{
+ T value;
+ simgear::readFrom(stream, value);
+ static_cast<SGRawValue<T>*>(this)->setValue(value);
+ return stream;
+}
\f
/**
* The smart pointer that manage reference counting
MAX_STRING_LEN = 1024
};
- /**
- * Property value types.
- */
- enum Type {
- NONE = 0,
- ALIAS,
- BOOL,
- INT,
- LONG,
- FLOAT,
- DOUBLE,
- STRING,
- UNSPECIFIED
- };
-
-
/**
* Access mode attributes.
*
/**
* Test whether this node contains a primitive leaf value.
*/
- bool hasValue () const { return (_type != NONE); }
+ bool hasValue () const { return (_type != simgear::props::NONE); }
/**
/**
* Test whether the node's leaf value is aliased to another's.
*/
- bool isAlias () const { return (_type == ALIAS); }
+ bool isAlias () const { return (_type == simgear::props::ALIAS); }
/**
/**
* Get the type of leaf value, if any, for this node.
*/
- Type getType () const;
+ simgear::props::Type getType () const;
/**
*/
const char * getStringValue () const;
-
+ /**
+ * Get a value from a node. If the actual type of the node doesn't
+ * match the desired type, a conversion isn't guaranteed.
+ */
+ template<typename T>
+ T getValue(typename boost::enable_if_c<simgear::props::PropertyTraits<T>::Internal>
+ ::type* dummy = 0) const;
+ // Getter for extended property
+ template<typename T>
+ T getValue(typename boost::disable_if_c<simgear::props::PropertyTraits<T>::Internal>
+ ::type* dummy = 0) const;
/**
* Set a bool value for this node.
*/
bool setUnspecifiedValue (const char * value);
+ template<typename T>
+ bool setValue(const T& val,
+ typename boost::enable_if_c<simgear::props::PropertyTraits<T>::Internal>
+ ::type* dummy = 0);
+ template<typename T>
+ bool setValue(const T& val,
+ typename boost::disable_if_c<simgear::props::PropertyTraits<T>::Internal>
+ ::type* dummy = 0);
+
+ /**
+ * Print the value of the property to a stream.
+ */
+ std::ostream& printOn(std::ostream& stream) const;
+
//
// Data binding.
//
*/
bool isTied () const { return _tied; }
-
- /**
- * Bind this node to an external bool source.
- */
- bool tie (const SGRawValue<bool> &rawValue, bool useDefault = true);
-
-
- /**
- * Bind this node to an external int source.
- */
- bool tie (const SGRawValue<int> &rawValue, bool useDefault = true);
-
-
- /**
- * Bind this node to an external long int source.
- */
- bool tie (const SGRawValue<long> &rawValue, bool useDefault = true);
-
-
- /**
- * Bind this node to an external float source.
- */
- bool tie (const SGRawValue<float> &rawValue, bool useDefault = true);
-
-
- /**
- * Bind this node to an external double source.
- */
- bool tie (const SGRawValue<double> &rawValue, bool useDefault = true);
-
-
- /**
- * Bind this node to an external string source.
- */
- bool tie (const SGRawValue<const char *> &rawValue, bool useDefault = true);
-
+ /**
+ * Bind this node to an external source.
+ */
+ template<typename T>
+ bool tie(const SGRawValue<T> &rawValue, bool useDefault = true);
/**
* Unbind this node from any external data source.
/**
* Get another node's type.
*/
- Type getType (const char * relative_path) const;
+ simgear::props::Type getType (const char * relative_path) const;
/**
* Get another node's type.
*/
- Type getType (const std::string& relative_path) const
+ simgear::props::Type getType (const std::string& relative_path) const
{ return getType(relative_path.c_str()); }
/**
*/
const char * make_string () const;
-
/**
* Trace a read access.
*/
mutable std::string _path;
mutable std::string _buffer;
hash_table * _path_cache;
- Type _type;
+ simgear::props::Type _type;
bool _tied;
int _attr;
// The right kind of pointer...
union {
SGPropertyNode * alias;
- SGRawValue<bool> * bool_val;
- SGRawValue<int> * int_val;
- SGRawValue<long> * long_val;
- SGRawValue<float> * float_val;
- SGRawValue<double> * double_val;
- SGRawValue<const char *> * string_val;
+ SGRaw* val;
} _value;
union {
};
-// Convenice functions for use in templates
+// Convenience functions for use in templates
template<typename T>
T getValue(const SGPropertyNode*);
return node->setStringValue(value.c_str());
}
+template<typename T>
+bool SGPropertyNode::tie(const SGRawValue<T> &rawValue, bool useDefault)
+{
+ using namespace simgear::props;
+ if (_type == ALIAS || _tied)
+ return false;
+
+ useDefault = useDefault && hasValue();
+ T old_val = SGRawValue<T>::DefaultValue;
+ if (useDefault)
+ old_val = getValue<T>(this);
+ clearValue();
+ if (PropertyTraits<T>::Internal)
+ _type = PropertyTraits<T>::type_tag;
+ else
+ _type = EXTENDED;
+ _tied = true;
+ _value.val = rawValue.clone();
+ if (useDefault)
+ setValue(old_val);
+ return true;
+}
+
+template<>
+bool SGPropertyNode::tie (const SGRawValue<const char *> &rawValue,
+ bool useDefault);
+
+template<typename T>
+T SGPropertyNode::getValue(typename boost::disable_if_c<simgear::props
+ ::PropertyTraits<T>::Internal>::type* dummy) const
+{
+ using namespace simgear::props;
+ if (_attr == (READ|WRITE) && _type == EXTENDED
+ && _value.val->getType() == PropertyTraits<T>::type_tag) {
+ return static_cast<SGRawValue<T>*>(_value.val)->getValue();
+ }
+ if (getAttribute(TRACE_READ))
+ trace_read();
+ if (!getAttribute(READ))
+ return SGRawValue<T>::DefaultValue;
+ switch (_type) {
+ case EXTENDED:
+ if (_value.val->getType() == PropertyTraits<T>::type_tag)
+ return static_cast<SGRawValue<T>*>(_value.val)->getValue();
+ break;
+ case STRING:
+ case UNSPECIFIED:
+ return simgear::parseString<T>(make_string());
+ break;
+ }
+ return SGRawValue<T>::DefaultValue;
+}
+
+template<typename T>
+inline T SGPropertyNode::getValue(typename boost::enable_if_c<simgear::props
+ ::PropertyTraits<T>::Internal>::type* dummy) const
+{
+ return ::getValue<T>(this);
+}
+
+template<typename T>
+bool SGPropertyNode::setValue(const T& val,
+ typename boost::disable_if_c<simgear::props
+ ::PropertyTraits<T>::Internal>::type* dummy)
+{
+ using namespace simgear::props;
+ if (_attr == (READ|WRITE) && _type == EXTENDED
+ && _value.val->getType() == PropertyTraits<T>::type_tag) {
+ static_cast<SGRawValue<T>*>(_value.val)->setValue(val);
+ return true;
+ }
+ if (getAttribute(WRITE)
+ && ((_type == EXTENDED
+ && _value.val->getType() == PropertyTraits<T>::type_tag)
+ || _type == NONE || _type == UNSPECIFIED)) {
+ if (_type == NONE || _type == UNSPECIFIED) {
+ clearValue();
+ _type = EXTENDED;
+ _value.val = new SGRawValueContainer<T>(val);
+ } else {
+ static_cast<SGRawValue<T>*>(_value.val)->setValue(val);
+ }
+ if (getAttribute(TRACE_WRITE))
+ trace_write();
+ return true;
+ }
+ return false;
+}
+
+template<typename T>
+inline bool SGPropertyNode::setValue(const T& val,
+ typename boost::enable_if_c<simgear::props
+ ::PropertyTraits<T>::Internal>::type* dummy)
+{
+ return ::setValue(this, val);
+}
#endif // __PROPS_HXX
// end of props.hxx
projects / simgear.git / blobdiff