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#pragma once
#include "Object.h"
#include "Lock.h"
#include "Semaphore.h"
//An implementation of a readers-writers algorithm.
//Usage: Declare the ReadWrite, then lock by instantiating Reader or Writer.
class ReadWrite : NoCopy {
public:
ReadWrite();
~ReadWrite();
//Lock as reader
class Reader : NoCopy {
public:
Reader(const ReadWrite &rw);
~Reader();
private:
const ReadWrite &rw;
};
//Lock as writer
class Writer : NoCopy {
public:
//Could be const ReadWrite &rw, but if you need the const version
//you are probably mis-using this object...
Writer(ReadWrite &rw);
~Writer();
private:
ReadWrite &rw;
};
private:
mutable nat readers;
mutable util::Lock readersLock;
mutable Semaphore writers;
};
//Simplification of locking as reader and writer.
typedef ReadWrite::Reader Reader;
typedef ReadWrite::Writer Writer;
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