MNRopeRefCount.h

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/*
 * Copyright (c) 1997
 * Silicon Graphics Computer Systems, Inc.
 *
 * Permission to use, copy, modify, distribute and sell this software
 * and its documentation for any purpose is hereby granted without fee,
 * provided that the above copyright notice appear in all copies and
 * that both that copyright notice and this permission notice appear
 * in supporting documentation.  Silicon Graphics makes no
 * representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied warranty.
 *
 * Heavily modified by KOM/Darmstadt University of Technology, 2000
 */
#ifndef _R_REF_COUNT_H
#define _R_REF_COUNT_H

#include "mnthread.h"

#include <sys/types.h>
#include <string.h>
#include <stdlib.h>

// Class MNRopeRefCount provides a type, size_t, a data member,
// _M_ref_count, and member functions _M_incr and _M_decr, which perform
// atomic preincrement/predecrement.  The constructor initializes 
// _M_ref_count.

struct MNRopeRefCount
{
    // The data member _M_ref_count
    volatile size_t  _M_ref_count;

    // Constructor
/* #ifdef _THREAD_SAFE */
    mnthread_mutex_t _M_ref_count_lock;
/* # endif */

    MNRopeRefCount(size_t __n);

    virtual ~MNRopeRefCount();

    // _M_incr and _M_decr
    void   _M_incr();
    size_t _M_decr();
};

static inline int max( int a, int b )
{
    if ( a > b ) return a;
    return b;
}

static inline int min( int a, int b )
{
    if ( a < b ) return a;
    return b;
}
/*
 * There is an STL header file for these functions
 */
inline void uninitialized_copy_n( const uchar_t* src, size_t len, uchar_t* dest )
{
    memmove(dest,src,len);
}

inline void copy_n( const uchar_t* src, size_t len, uchar_t* dest )
{
    memmove(dest,src,len);
}

inline void uninitialized_fill_n( uchar_t* dest, size_t len, uchar_t c )
{
    memset(dest,c,len);
}

/*
 * Destroy calls destructor code without releasing memory.
 * In this case, we don't care.
 */
inline void destroy( uchar_t* /* bits */, size_t /* len */ )
{ }

inline void destroy( uchar_t* /* from */, uchar_t* /* to */ )
{ }


#endif /* _R_REF_COUNT_H */

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