nameinfo.hh

Click is a modular router toolkit. To use it you ll need to know how to compile and install the sof

    virtual ~NameDB() {
	NameInfo::uninstalldb(this);
    }

    /** @brief Return the database type. */
    uint32_t type() const {
	return _type;
    }

    /** @brief Return the database's compound element context as a string. */
    const String &context() const {
	return _context;
    }

    /** @brief Return the contextual parent database, if any.
     *
     * The contextual parent database is the unique database, for the same
     * router, with the same type(), whose context() is a prefix of this
     * database's context(), that has the longest context() of any matching
     * database.  If there is no such database returns null. */
    NameDB *context_parent() const {
	return _context_parent;
    }

    /** @brief Return the database's value size. */
    size_t value_size() const {
	return _value_size;
    }

    /** @brief Query this database for a given name.
     * @param name name to look up
     * @param value points to value storage
     * @param value_size size of value storage
     * @return true iff the query succeeded
     *
     * The @a value_size parameter must equal this database's value size. */
    virtual bool query(const String &name, void *value, size_t value_size) = 0;

    /** @brief Query this database for a given value.
     * @param value points to value to look up
     * @param value_size size of value storage
     * @return the name for the given value, or an empty string if the value
     * has not been defined
     *
     * The @a value_size parameter must equal this database's value size.
     * The default implementation always returns the empty string. */
    virtual String revquery(const void *value, size_t value_size);

    /** @brief Define a name in this database to a given value.
     * @param name name to define
     * @param value points to value to define
     * @param value_size size of value storage
     * @return true iff the name was defined
     *
     * The @a value_size parameter must equal this database's value size.
     * The default implementation always returns false. */
    virtual bool define(const String &name, const void *value, size_t value_size);

    /** @brief Define a name in this database to a 32-bit integer value.
     * @param name name to define
     * @param value value to define
     * @return true iff the name was defined
     *
     * The database's value size must equal 4.  The implementation is the same
     * as <code>define(name, &value, 4)</code>. */
    inline bool define_int(const String &name, int32_t value);

#if CLICK_NAMEDB_CHECK
    /** @cond never */
    virtual void check(ErrorHandler *);
    /** @endcond never */
#endif

  private:

    uint32_t _type;
    String _context;
    size_t _value_size;
    NameDB *_context_parent;
    NameDB *_context_sibling;
    NameDB *_context_child;
    NameInfo *_installed;

#if CLICK_NAMEDB_CHECK
    uintptr_t _check_generation;
#endif

    friend class NameInfo;

};

class StaticNameDB : public NameDB { public:

    struct Entry {
	const char *name;
	uint32_t value;
    };

    /** @brief Construct a static name database.
     * @param type database type
     * @param context database compound element context, as a String
     * @param entry pointer to static entry list
     * @param nentry number of entries
     *
     * The entry array specifies the contents of the database.  It must be
     * sorted by name: entry[i].name < entry[i+1].name for all 0 <= i <
     * nentry-1.  The entry array must also persist as long as the database is
     * in use; the database doesn't copy the entry array into its own memory,
     * but continues to use the array passed in.  The resulting database has
     * value_size() 4. */
    inline StaticNameDB(uint32_t type, const String &context,
			const Entry *entry, size_t nentry);

    /** @brief Query this database for a given name.
     * @param name name to look up
     * @param value points to value storage
     * @param value_size size of value storage
     * @return true iff the query succeeded
     *
     * The @a value_size parameter must equal 4. */
    bool query(const String &name, void *value, size_t value_size);

    /** @brief Query this database for a given value.
     * @param value points to value to look up
     * @param value_size size of value storage
     * @return the name for the given value, or an empty string if the value
     * has not been defined
     *
     * The @a value_size parameter must equal 4. */
    String revquery(const void *value, size_t value_size);

#if CLICK_NAMEDB_CHECK
    /** @cond never */
    void check(ErrorHandler *);
    /** @endcond never */
#endif

  private:

    const Entry *_entries;
    size_t _nentries;

};

class DynamicNameDB : public NameDB { public:

    /** @brief Construct a dynamic name database.
     * @param type database type
     * @param context database compound element context, as a String
     * @param value_size database value size
     *
     * @a value_size must be greater than 0.  The database is initially
     * empty. */
    inline DynamicNameDB(uint32_t type, const String &context, size_t value_size);

    /** @brief Query this database for a given name.
     * @param name name to look up
     * @param value points to value storage
     * @param value_size size of value storage
     * @return true iff the query succeeded
     *
     * The @a value_size parameter must equal this database's value size. */
    bool query(const String &name, void *value, size_t value_size);

    /** @brief Query this database for a given value.
     * @param value points to value to look up
     * @param value_size size of value storage
     * @return the name for the given value, or an empty string if the value
     * has not been defined
     *
     * The @a value_size parameter must equal this database's value size. */
    String revquery(const void *value, size_t value_size);

    /** @brief Define a name in this database to a given value.
     * @param name name to define
     * @param value points to value to define
     * @param value_size size of value storage
     * @return true iff the name was defined
     *
     * The @a value_size parameter must equal this database's value size. */
    bool define(const String &name, const void *value, size_t value_size);

#if CLICK_NAMEDB_CHECK
    /** @cond never */
    void check(ErrorHandler *);
    /** @endcond never */
#endif

  private:

    Vector<String> _names;
    StringAccum _values;
    int _sorted;

    void *find(const String &name, bool create);
    void sort();

};


inline
NameDB::NameDB(uint32_t type, const String &context, size_t vsize)
    : _type(type), _context(context), _value_size(vsize),
      _context_parent(0), _context_sibling(0), _context_child(0), _installed(0)
{
#if CLICK_NAMEDB_CHECK
    _check_generation = 0;
#endif
    assert(_value_size > 0);
}

inline
StaticNameDB::StaticNameDB(uint32_t type, const String &context, const Entry *entry, size_t nentry)
    : NameDB(type, context, sizeof(entry->value)), _entries(entry), _nentries(nentry)
{
}

inline
DynamicNameDB::DynamicNameDB(uint32_t type, const String &context, size_t vsize)
    : NameDB(type, context, vsize), _sorted(0)
{
}

inline String
NameInfo::revquery_int(uint32_t type, const Element *e, int32_t value)
{
    return revquery(type, e, &value, sizeof(value));
}

inline bool
NameInfo::define(uint32_t type, const Element *e, const String &name, const void *value, size_t vsize)
{
    if (NameDB *db = getdb(type, e, vsize, true))
	return db->define(name, value, vsize);
    else
	return false;
}

inline bool
NameInfo::define_int(uint32_t type, const Element *e, const String &name, const int32_t value)
{
    if (NameDB *db = getdb(type, e, sizeof(value), true))
	return db->define(name, &value, sizeof(value));
    else
	return false;
}

inline bool
NameDB::define_int(const String &name, const int32_t value)
{
    return define(name, &value, sizeof(value));
}

CLICK_ENDDECLS
#endif