ClickHouse/base/poco/Foundation/include/Poco/FunctionDelegate.h

//
// FunctionDelegate.h
//
// Library: Foundation
// Package: Events
// Module:  FunctionDelegate
//
// Implementation of the FunctionDelegate template.
//
// Copyright (c) 2006-2011, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// SPDX-License-Identifier:	BSL-1.0
//


#ifndef Foundation_FunctionDelegate_INCLUDED
#define Foundation_FunctionDelegate_INCLUDED


#include "Poco/AbstractDelegate.h"
#include "Poco/Foundation.h"
#include "Poco/Mutex.h"


namespace Poco
{


template <class TArgs, bool hasSender = true, bool senderIsConst = true>
class FunctionDelegate : public AbstractDelegate<TArgs>
/// Wraps a freestanding function or static member function
/// for use as a Delegate.
{
public:
    typedef void (*NotifyFunction)(const void *, TArgs &);

    FunctionDelegate(NotifyFunction function) : _function(function) { }

    FunctionDelegate(const FunctionDelegate & delegate) : AbstractDelegate<TArgs>(delegate), _function(delegate._function) { }

    ~FunctionDelegate() { }

    FunctionDelegate & operator=(const FunctionDelegate & delegate)
    {
        if (&delegate != this)
        {
            this->_function = delegate._function;
        }
        return *this;
    }

    bool notify(const void * sender, TArgs & arguments)
    {
        Mutex::ScopedLock lock(_mutex);
        if (_function)
        {
            (*_function)(sender, arguments);
            return true;
        }
        else
            return false;
    }

    bool equals(const AbstractDelegate<TArgs> & other) const
    {
        const FunctionDelegate * pOtherDelegate = dynamic_cast<const FunctionDelegate *>(other.unwrap());
        return pOtherDelegate && _function == pOtherDelegate->_function;
    }

    AbstractDelegate<TArgs> * clone() const { return new FunctionDelegate(*this); }

    void disable()
    {
        Mutex::ScopedLock lock(_mutex);
        _function = 0;
    }

protected:
    NotifyFunction _function;
    Mutex _mutex;

private:
    FunctionDelegate();
};


template <class TArgs>
class FunctionDelegate<TArgs, true, false> : public AbstractDelegate<TArgs>
{
public:
    typedef void (*NotifyFunction)(void *, TArgs &);

    FunctionDelegate(NotifyFunction function) : _function(function) { }

    FunctionDelegate(const FunctionDelegate & delegate) : AbstractDelegate<TArgs>(delegate), _function(delegate._function) { }

    ~FunctionDelegate() { }

    FunctionDelegate & operator=(const FunctionDelegate & delegate)
    {
        if (&delegate != this)
        {
            this->_function = delegate._function;
        }
        return *this;
    }

    bool notify(const void * sender, TArgs & arguments)
    {
        Mutex::ScopedLock lock(_mutex);
        if (_function)
        {
            (*_function)(const_cast<void *>(sender), arguments);
            return true;
        }
        else
            return false;
    }

    bool equals(const AbstractDelegate<TArgs> & other) const
    {
        const FunctionDelegate * pOtherDelegate = dynamic_cast<const FunctionDelegate *>(other.unwrap());
        return pOtherDelegate && _function == pOtherDelegate->_function;
    }

    AbstractDelegate<TArgs> * clone() const { return new FunctionDelegate(*this); }

    void disable()
    {
        Mutex::ScopedLock lock(_mutex);
        _function = 0;
    }

protected:
    NotifyFunction _function;
    Mutex _mutex;

private:
    FunctionDelegate();
};


template <class TArgs, bool senderIsConst>
class FunctionDelegate<TArgs, false, senderIsConst> : public AbstractDelegate<TArgs>
{
public:
    typedef void (*NotifyFunction)(TArgs &);

    FunctionDelegate(NotifyFunction function) : _function(function) { }

    FunctionDelegate(const FunctionDelegate & delegate) : AbstractDelegate<TArgs>(delegate), _function(delegate._function) { }

    ~FunctionDelegate() { }

    FunctionDelegate & operator=(const FunctionDelegate & delegate)
    {
        if (&delegate != this)
        {
            this->_function = delegate._function;
        }
        return *this;
    }

    bool notify(const void * /*sender*/, TArgs & arguments)
    {
        Mutex::ScopedLock lock(_mutex);
        if (_function)
        {
            (*_function)(arguments);
            return true;
        }
        else
            return false;
    }

    bool equals(const AbstractDelegate<TArgs> & other) const
    {
        const FunctionDelegate * pOtherDelegate = dynamic_cast<const FunctionDelegate *>(other.unwrap());
        return pOtherDelegate && _function == pOtherDelegate->_function;
    }

    AbstractDelegate<TArgs> * clone() const { return new FunctionDelegate(*this); }

    void disable()
    {
        Mutex::ScopedLock lock(_mutex);
        _function = 0;
    }

protected:
    NotifyFunction _function;
    Mutex _mutex;

private:
    FunctionDelegate();
};


template <>
class FunctionDelegate<void, true, true> : public AbstractDelegate<void>
/// Wraps a freestanding function or static member function
/// for use as a Delegate.
{
public:
    typedef void (*NotifyFunction)(const void *);

    FunctionDelegate(NotifyFunction function) : _function(function) { }

    FunctionDelegate(const FunctionDelegate & delegate) : AbstractDelegate<void>(delegate), _function(delegate._function) { }

    ~FunctionDelegate() { }

    FunctionDelegate & operator=(const FunctionDelegate & delegate)
    {
        if (&delegate != this)
        {
            this->_function = delegate._function;
        }
        return *this;
    }

    bool notify(const void * sender)
    {
        Mutex::ScopedLock lock(_mutex);
        if (_function)
        {
            (*_function)(sender);
            return true;
        }
        else
            return false;
    }

    bool equals(const AbstractDelegate<void> & other) const
    {
        const FunctionDelegate * pOtherDelegate = dynamic_cast<const FunctionDelegate *>(other.unwrap());
        return pOtherDelegate && _function == pOtherDelegate->_function;
    }

    AbstractDelegate<void> * clone() const { return new FunctionDelegate(*this); }

    void disable()
    {
        Mutex::ScopedLock lock(_mutex);
        _function = 0;
    }

protected:
    NotifyFunction _function;
    Mutex _mutex;

private:
    FunctionDelegate();
};


template <>
class FunctionDelegate<void, true, false> : public AbstractDelegate<void>
{
public:
    typedef void (*NotifyFunction)(void *);

    FunctionDelegate(NotifyFunction function) : _function(function) { }

    FunctionDelegate(const FunctionDelegate & delegate) : AbstractDelegate<void>(delegate), _function(delegate._function) { }

    ~FunctionDelegate() { }

    FunctionDelegate & operator=(const FunctionDelegate & delegate)
    {
        if (&delegate != this)
        {
            this->_function = delegate._function;
        }
        return *this;
    }

    bool notify(const void * sender)
    {
        Mutex::ScopedLock lock(_mutex);
        if (_function)
        {
            (*_function)(const_cast<void *>(sender));
            return true;
        }
        else
            return false;
    }

    bool equals(const AbstractDelegate<void> & other) const
    {
        const FunctionDelegate * pOtherDelegate = dynamic_cast<const FunctionDelegate *>(other.unwrap());
        return pOtherDelegate && _function == pOtherDelegate->_function;
    }

    AbstractDelegate<void> * clone() const { return new FunctionDelegate(*this); }

    void disable()
    {
        Mutex::ScopedLock lock(_mutex);
        _function = 0;
    }

protected:
    NotifyFunction _function;
    Mutex _mutex;

private:
    FunctionDelegate();
};


template <bool senderIsConst>
class FunctionDelegate<void, false, senderIsConst> : public AbstractDelegate<void>
{
public:
    typedef void (*NotifyFunction)();

    FunctionDelegate(NotifyFunction function) : _function(function) { }

    FunctionDelegate(const FunctionDelegate & delegate) : AbstractDelegate<void>(delegate), _function(delegate._function) { }

    ~FunctionDelegate() { }

    FunctionDelegate & operator=(const FunctionDelegate & delegate)
    {
        if (&delegate != this)
        {
            this->_function = delegate._function;
        }
        return *this;
    }

    bool notify(const void * /*sender*/)
    {
        Mutex::ScopedLock lock(_mutex);
        if (_function)
        {
            (*_function)();
            return true;
        }
        else
            return false;
    }

    bool equals(const AbstractDelegate<void> & other) const
    {
        const FunctionDelegate * pOtherDelegate = dynamic_cast<const FunctionDelegate *>(other.unwrap());
        return pOtherDelegate && _function == pOtherDelegate->_function;
    }

    AbstractDelegate<void> * clone() const { return new FunctionDelegate(*this); }

    void disable()
    {
        Mutex::ScopedLock lock(_mutex);
        _function = 0;
    }

protected:
    NotifyFunction _function;
    Mutex _mutex;

private:
    FunctionDelegate();
};


} // namespace Poco


#endif // Foundation_FunctionDelegate_INCLUDED