OptionDictionary.h revision 1.1.4.2 
1/*
2 * File:	OptionDictionary.h
3 *
4 * Copyright (c) Freescale Semiconductor, Inc. All rights reserved.
5 * See included license file for license details.
6 */
7#if !defined(_OptionDictionary_h_)
8#define _OptionDictionary_h_
9
10#include "OptionContext.h"
11#include <map>
12
13namespace elftosb
14{
15
16/*!
17 * \brief Concrete implementation of OptionContext.
18 *
19 * This context subclass supports having a parent context. If an option is not
20 * found in the receiving instance, the request is passed to the parent.
21 * The hasOption() and getOption() methods will ask up the parent chain
22 * if the requested option does not exist in the receiving instance.
23 * But the setOption() and deleteOption() methods only operate locally,
24 * on the instance on which they were called. This allows a caller to
25 * locally override an option value without affecting any of the parent
26 * contexts.
27 */
28class OptionDictionary : public OptionContext
29{
30public:
31	//! \brief Default constructor.
32	OptionDictionary() : m_parent(0) {}
33
34	//! \brief Constructor taking a parent context.
35	OptionDictionary(OptionContext * parent) : m_parent(parent) {}
36
37	//! \brief Destructor.
38	~OptionDictionary();
39
40	//! \name Parents
41	//@{
42	//! \brief Returns the current parent context.
43	//! \return The current parent context instance.
44	//! \retval NULL No parent has been set.
45	inline OptionContext * getParent() const { return m_parent; }
46
47	//! \brief Change the parent context.
48	//! \param newParent The parent context object. May be NULL, in which case
49	//!		the object will no longer have a parent context.
50	inline void setParent(OptionContext * newParent) { m_parent = newParent; }
51	//@}
52
53	//! \name Options
54	//@{
55	//! \brief Detemine whether the named option is present in the table.
56	virtual bool hasOption(const std::string & name) const;
57
58	//! \brief Returns the option's value.
59	virtual const Value * getOption(const std::string & name) const;
60
61	//! \brief Adds or changes an option's value.
62	virtual void setOption(const std::string & name, Value * value);
63
64	//! \brief Removes an option from the table.
65	virtual void deleteOption(const std::string & name);
66	//@}
67
68	//! \name Locking
69	//@{
70	//! \brief Returns true if the specified option is locked from further changes.
71	bool isOptionLocked(const std::string & name) const;
72
73	//! \brief Prevent further modifications of an option's value.
74	void lockOption(const std::string & name);
75
76	//! \brief Allow an option to be changed.
77	void unlockOption(const std::string & name);
78	//@}
79
80	//! \name Operators
81	//@{
82	//! \brief Indexing operator; returns the value for the option \a name.
83	const Value * operator [] (const std::string & name) const;
84	//@}
85
86protected:
87	OptionContext * m_parent;	//!< Our parent context.
88
89	/*!
90	 * \brief Information about one option's value.
91	 */
92	struct OptionValue
93	{
94		Value * m_value;	//!< The object for this option's value.
95		bool m_isLocked;	//!< True if this value is locked from further changes.
96
97		//! \brief Constructor.
98		OptionValue() : m_value(0), m_isLocked(false) {}
99	};
100
101	typedef std::map<std::string, OptionValue> option_map_t;	//!< Map from option name to value.
102	option_map_t m_options;	//!< The option dictionary.
103};
104
105}; // namespace elftosb
106
107#endif // _OptionDictionary_h_
108