find.h

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/*******************************************************************************
 *
 * Copyright (c) 2008-2010 Michael Schulze <mschulze@ivs.cs.uni-magdeburg.de>
 *                    2010 Marcus Foerster <MarcusFoerster1@gmx.de>
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#ifndef _Find_h_
#define _Find_h_

#include <stdint.h>

#include "mw/attributes/access/AttributeSetHeader_RT.h"
#include "mw/attributes/access/AttributeHeader_RT.h"
#include "mw/attributes/access/Attribute_RT.h"

namespace famouso {
    namespace mw {
        namespace attributes {
            namespace detail {

                static void* find_impl(uint8_t* data, const uint8_t id, const bool highDensity) {
                    // The number of bytes needed by the attributes
                    //  contained in the given sequence
                    uint16_t seqLen;

                    {
                        typedef famouso::mw::attributes::access::AttributeSetHeader_RT setHeaderType;

                        const setHeaderType* const setHeader = reinterpret_cast<const setHeaderType* const>(&data[0]);

                        seqLen = setHeader->contentLength();

                        data += setHeader->headerLength();
                    }

                    // The pointer were the given sequence ends
                    const uint8_t* const targetPtr = data + seqLen;

                    typedef famouso::mw::attributes::access::AttributeHeader_RT headerType;
                    typedef famouso::mw::attributes::access::Attribute_RT attrType;

                    const headerType* header;

                    while (data < targetPtr) {
                        header = reinterpret_cast<const headerType*>(data);

                        // Check if the encoded attribute fits the given one
                        if ((header->isHighDensity() == highDensity) && (header->getID() == id)) {
                            return (data);
                        }

                        // We let the attribute class determine its overall size to skip it
                        data += reinterpret_cast<const attrType* const>(header)->length();
                    }

                    // If we iterated the complete attribute sequence the intended attribute
                    //  could not be found and NULL is returned
                    return (NULL);
                }

                template <typename Attr>
                static inline Attr* find(uint8_t* data) {
                    return (reinterpret_cast<Attr*>(find_impl(data, Attr::id, Attr::highDensity)));
                }

                template <typename Attr>
                static inline const Attr* find(const uint8_t* data) {
                    return (reinterpret_cast<const Attr*>(find_impl(const_cast<uint8_t*>(data), Attr::id, Attr::highDensity)));
                }

            } // end namespace detail
        } // end namespace attributes
    } // end namespace attributes
} // end namespace attributes

#endif