annotate base/ResizeableBitset.h @ 316:3a6725f285d6

* Make RemoteFile far more pervasive, and use it for local files as well
  so that we can handle both transparently.  Make it shallow copy with
  reference counting, so it can be used by value without having to worry
  about the cache file lifetime.  Use RemoteFile for MainWindow file-open
  functions, etc

/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */

/*
    Sonic Visualiser
    An audio file viewer and annotation editor.
    Centre for Digital Music, Queen Mary, University of London.
    This file copyright 2006 Chris Cannam.
    
    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License as
    published by the Free Software Foundation; either version 2 of the
    License, or (at your option) any later version.  See the file
    COPYING included with this distribution for more information.
*/

#ifndef _RESIZEABLE_BITMAP_H_
#define _RESIZEABLE_BITMAP_H_

#include <vector>
#include <stdint.h>

class ResizeableBitset {

public:
    ResizeableBitset() : m_bits(0) {
    }
    ResizeableBitset(size_t size) : m_bits(new std::vector<uint8_t>) {
        m_bits->assign((size >> 3) + 1, 0);
    }
    ResizeableBitset(const ResizeableBitset &b) {
        m_bits = new std::vector<uint8_t>(*b.m_bits);
    }
    ResizeableBitset &operator=(const ResizeableBitset &b) {
        if (&b != this) return *this;
        delete m_bits;
        m_bits = new std::vector<uint8_t>(*b.m_bits);
        return *this;
    }
    ~ResizeableBitset() {
        delete m_bits;
    }
    
    void resize(size_t bits) { // losing all data
        if (!m_bits || bits < m_bits->size()) {
            delete m_bits;
            m_bits = new std::vector<uint8_t>;
        }
        m_bits->assign((bits >> 3) + 1, 0);
    }
    
    bool get(size_t column) const {
        return ((*m_bits)[column >> 3]) & (1u << (column & 0x07));
    }
    
    void set(size_t column) {
        ((*m_bits)[column >> 3]) |=  (uint8_t(1) << (column & 0x07));
    }

    void reset(size_t column) {
        ((*m_bits)[column >> 3]) &= ~(uint8_t(1) << (column & 0x07));
    }

    void copy(size_t source, size_t dest) {
        get(source) ? set(dest) : reset(dest);
    }
    
private:
    std::vector<uint8_t> *m_bits;
};


#endif