sux 0.12.3

A pure Rust implementation of succinct and compressed data structures
Documentation 
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/**
 * This code is released under the
 * Apache License Version 2.0 http://www.apache.org/licenses/.
 *
 * (c) Daniel Lemire, http://lemire.me/en/
 */
#ifndef COMPOSITECODEC_H_
#define COMPOSITECODEC_H_

#include "common.h"
#include "util.h"
#include "codecs.h"

namespace FastPFor {

/**
 * This is a useful class for CODEC that only compress
 * data having length a multiple of some unit length.
 */
template<class Codec1, class Codec2>
class CompositeCodec: public IntegerCODEC {
public:
    CompositeCodec() :
        codec1(), codec2() {
    }
    Codec1 codec1;
    Codec2 codec2;
    void encodeArray(const uint32_t * in, const size_t length, uint32_t * out,
            size_t &nvalue) {
        const size_t roundedlength = length / Codec1::BlockSize
                * Codec1::BlockSize;
        size_t nvalue1 = nvalue;
        codec1.encodeArray(in, roundedlength, out, nvalue1);

        if (roundedlength < length) {
            ASSERT(nvalue >= nvalue1, nvalue << " " << nvalue1);
            size_t nvalue2 = nvalue - nvalue1;
            codec2.encodeArray(in + roundedlength, length - roundedlength,
                    out + nvalue1, nvalue2);
            nvalue = nvalue1 + nvalue2;
        } else {
            nvalue = nvalue1;
        }
    }
    const uint32_t * decodeArray(const uint32_t *in, const size_t length,
            uint32_t *out, size_t & nvalue) {
#ifndef NDEBUG
        const uint32_t * const initin(in);
#endif
        size_t mynvalue1 = nvalue;
        const uint32_t *in2 = codec1.decodeArray(in, length, out, mynvalue1);
        if (length + in > in2) {
            assert(nvalue > mynvalue1);
            size_t nvalue2 = nvalue - mynvalue1;
            const uint32_t *in3 = codec2.decodeArray(in2, length - (in2 - in),
                    out + mynvalue1, nvalue2);
            nvalue = mynvalue1 + nvalue2;
            assert(initin + length >= in3);
            return in3;
        }
        nvalue = mynvalue1;
        assert(initin + length >= in2);
        return in2;
    }
    std::string name() const {
        std::ostringstream convert;
        convert << codec1.name() << "+" << codec2.name();
        return convert.str();
    }
};

} // namespace FastPFor

#endif /* COMPOSITECODEC_H_ */