avail.h

/*
 *  availability.h
 *  Tree keeping track of the availability of each bin in a swarm
 *
 *  Created by Riccardo Petrocco
 *  Copyright 2009-2012 Delft University of Technology. All rights reserved.
 *
 */
#include "bin.h"
#include "binmap.h"
#include "compat.h"
#include <cassert>
#include <vector>

#ifndef AVAILABILITY_H
#define AVAILABILITY_H

namespace swift {

typedef 	std::vector< std::pair<uint32_t, binmap_t*> >	WaitingPeers;

class Availability
{
    public:

	    /**
	     * Constructor
	     */
        explicit Availability(int connections)
	    {
	    	connections_ = connections;
	    	initRarity();
	    }

	    ~Availability(void)
		{
			for (int i=0; i<connections_; i++)
				delete rarity_[i];
			delete [] rarity_;
		}

	    /** sets the number of connections */
	    void setParams(int connections);

	    /** set/update the rarity */
	    void set(uint32_t channel_id, binmap_t& binmap, bin_t target);

	    /** removes the binmap of leaving peers */
	    void removeBinmap(uint32_t channel_id, binmap_t& binmap);

	    /** adds an entire binmap from the rarity array */
	    void addBinmap(binmap_t * binmap);

	    /** get rarest bin, of specified width, within a range */
	    bin_t getRarest(const bin_t range, int width);

	    /** returns the entire array of binmaps ordered by rarity */
	    binmap_t** getRarityArray() { return rarity_; }

	    /** returns a binmaps filled with bins of rarity idx */
	    binmap_t* get(int idx) { return rarity_[idx]; }

	    /** Echo the availability status to stdout */
		void status() const;

    protected:
	    // init with the number of connections.
	    // it is an array of pointers to binmaps, where the index represents the local view of
	    // availability in the swarm, of which the binmap is composed from the rare bins.
	    binmap_t **rarity_;
	    int connections_;


	    /** removes the binmap */
	    void removeBinmap(binmap_t& binmap);

	    /** removes the bin */
	    void removeBin(bin_t bin, int idx);

	    /** sets a bin */
	    void setBin(bin_t bin, int idx);

	    /** updates the rarity array*/
	    void updateRarity(bin_t bin, int idx);

	    /** initialize the rarity array */
	    void initRarity();

	    void find_empty(binmap_t& binmap, bin_t range);


};

}

#endif