concurrent_queue.h

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/*
    Copyright 2005-2010 Intel Corporation.  All Rights Reserved.

    This file is part of Threading Building Blocks.

    Threading Building Blocks is free software; you can redistribute it
    and/or modify it under the terms of the GNU General Public License
    version 2 as published by the Free Software Foundation.

    Threading Building Blocks is distributed in the hope that it will be
    useful, but WITHOUT ANY WARRANTY; without even the implied warranty
    of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with Threading Building Blocks; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    As a special exception, you may use this file as part of a free software
    library without restriction.  Specifically, if other files instantiate
    templates or use macros or inline functions from this file, or you compile
    this file and link it with other files to produce an executable, this
    file does not by itself cause the resulting executable to be covered by
    the GNU General Public License.  This exception does not however
    invalidate any other reasons why the executable file might be covered by
    the GNU General Public License.
*/

#ifndef __TBB_concurrent_queue_H
#define __TBB_concurrent_queue_H

#include "_concurrent_queue_internal.h"

namespace tbb {

namespace strict_ppl {


template<typename T, typename A = cache_aligned_allocator<T> > 
class concurrent_queue: public internal::concurrent_queue_base_v3<T> {
    template<typename Container, typename Value> friend class internal::concurrent_queue_iterator;

    typedef typename A::template rebind<char>::other page_allocator_type;
    page_allocator_type my_allocator;

    /*overide*/ virtual void *allocate_block( size_t n ) {
        void *b = reinterpret_cast<void*>(my_allocator.allocate( n ));
        if( !b )
            internal::throw_exception(internal::eid_bad_alloc); 
        return b;
    }

    /*override*/ virtual void deallocate_block( void *b, size_t n ) {
        my_allocator.deallocate( reinterpret_cast<char*>(b), n );
    }

public:
    typedef T value_type;

    typedef T& reference;

    typedef const T& const_reference;

    typedef size_t size_type;

    typedef ptrdiff_t difference_type;

    typedef A allocator_type;

    explicit concurrent_queue(const allocator_type& a = allocator_type()) : 
        my_allocator( a )
    {
    }

    template<typename InputIterator>
    concurrent_queue( InputIterator begin, InputIterator end, const allocator_type& a = allocator_type()) :
        my_allocator( a )
    {
        for( ; begin != end; ++begin )
            internal_push(&*begin);
    }
    
    concurrent_queue( const concurrent_queue& src, const allocator_type& a = allocator_type()) : 
        internal::concurrent_queue_base_v3<T>(), my_allocator( a )
    {
        assign( src );
    }
    
    ~concurrent_queue();

    void push( const T& source ) {
        internal_push( &source );
    }


    bool try_pop( T& result ) {
        return internal_try_pop( &result );
    }

    size_type unsafe_size() const {return this->internal_size();}

    bool empty() const {return this->internal_empty();}

    void clear() ;

    allocator_type get_allocator() const { return this->my_allocator; }

    typedef internal::concurrent_queue_iterator<concurrent_queue,T> iterator;
    typedef internal::concurrent_queue_iterator<concurrent_queue,const T> const_iterator;

    //------------------------------------------------------------------------
    // The iterators are intended only for debugging.  They are slow and not thread safe.
    //------------------------------------------------------------------------
    iterator unsafe_begin() {return iterator(*this);}
    iterator unsafe_end() {return iterator();}
    const_iterator unsafe_begin() const {return const_iterator(*this);}
    const_iterator unsafe_end() const {return const_iterator();}
} ;

template<typename T, class A>
concurrent_queue<T,A>::~concurrent_queue() {
    clear();
    this->internal_finish_clear();
}

template<typename T, class A>
void concurrent_queue<T,A>::clear() {
    while( !empty() ) {
        T value;
        this->internal_try_pop(&value);
    }
}

} // namespace strict_ppl
    

template<typename T, class A = cache_aligned_allocator<T> >
class concurrent_bounded_queue: public internal::concurrent_queue_base_v3 {
    template<typename Container, typename Value> friend class internal::concurrent_queue_iterator;

    typedef typename A::template rebind<char>::other page_allocator_type;
    page_allocator_type my_allocator;

    typedef typename concurrent_queue_base_v3::padded_page<T> padded_page;
 
    class destroyer: internal::no_copy {
        T& my_value;
    public:
        destroyer( T& value ) : my_value(value) {}
        ~destroyer() {my_value.~T();}          
    };

    T& get_ref( page& p, size_t index ) {
        __TBB_ASSERT( index<items_per_page, NULL );
        return (&static_cast<padded_page*>(static_cast<void*>(&p))->last)[index];
    }

    /*override*/ virtual void copy_item( page& dst, size_t index, const void* src ) {
        new( &get_ref(dst,index) ) T(*static_cast<const T*>(src)); 
    }

    /*override*/ virtual void copy_page_item( page& dst, size_t dindex, const page& src, size_t sindex ) {
        new( &get_ref(dst,dindex) ) T( get_ref( const_cast<page&>(src), sindex ) );
    }

    /*override*/ virtual void assign_and_destroy_item( void* dst, page& src, size_t index ) {
        T& from = get_ref(src,index);
        destroyer d(from);
        *static_cast<T*>(dst) = from;
    }

    /*overide*/ virtual page *allocate_page() {
        size_t n = sizeof(padded_page) + (items_per_page-1)*sizeof(T);
        page *p = reinterpret_cast<page*>(my_allocator.allocate( n ));
        if( !p )
            internal::throw_exception(internal::eid_bad_alloc); 
        return p;
    }

    /*override*/ virtual void deallocate_page( page *p ) {
        size_t n = sizeof(padded_page) + items_per_page*sizeof(T);
        my_allocator.deallocate( reinterpret_cast<char*>(p), n );
    }

public:
    typedef T value_type;

    typedef A allocator_type;

    typedef T& reference;

    typedef const T& const_reference;


    typedef std::ptrdiff_t size_type;

    typedef std::ptrdiff_t difference_type;

    explicit concurrent_bounded_queue(const allocator_type& a = allocator_type()) : 
        concurrent_queue_base_v3( sizeof(T) ), my_allocator( a )
    {
    }

    concurrent_bounded_queue( const concurrent_bounded_queue& src, const allocator_type& a = allocator_type()) : 
        concurrent_queue_base_v3( sizeof(T) ), my_allocator( a )
    {
        assign( src );
    }

    template<typename InputIterator>
    concurrent_bounded_queue( InputIterator begin, InputIterator end, const allocator_type& a = allocator_type()) :
        concurrent_queue_base_v3( sizeof(T) ), my_allocator( a )
    {
        for( ; begin != end; ++begin )
            internal_push_if_not_full(&*begin);
    }

    ~concurrent_bounded_queue();

    void push( const T& source ) {
        internal_push( &source );
    }


    void pop( T& destination ) {
        internal_pop( &destination );
    }


    bool try_push( const T& source ) {
        return internal_push_if_not_full( &source );
    }


    bool try_pop( T& destination ) {
        return internal_pop_if_present( &destination );
    }


    size_type size() const {return internal_size();}

    bool empty() const {return internal_empty();}

    size_type capacity() const {
        return my_capacity;
    }


    void set_capacity( size_type new_capacity ) {
        internal_set_capacity( new_capacity, sizeof(T) );
    }

    allocator_type get_allocator() const { return this->my_allocator; }

    void clear() ;

    typedef internal::concurrent_queue_iterator<concurrent_bounded_queue,T> iterator;
    typedef internal::concurrent_queue_iterator<concurrent_bounded_queue,const T> const_iterator;

    //------------------------------------------------------------------------
    // The iterators are intended only for debugging.  They are slow and not thread safe.
    //------------------------------------------------------------------------
    iterator unsafe_begin() {return iterator(*this);}
    iterator unsafe_end() {return iterator();}
    const_iterator unsafe_begin() const {return const_iterator(*this);}
    const_iterator unsafe_end() const {return const_iterator();}

}; 

template<typename T, class A>
concurrent_bounded_queue<T,A>::~concurrent_bounded_queue() {
    clear();
    internal_finish_clear();
}

template<typename T, class A>
void concurrent_bounded_queue<T,A>::clear() {
    while( !empty() ) {
        T value;
        internal_pop_if_present(&value);
    }
}

namespace deprecated {


template<typename T, class A = cache_aligned_allocator<T> > 
class concurrent_queue: public concurrent_bounded_queue<T,A> {
#if !__TBB_TEMPLATE_FRIENDS_BROKEN
    template<typename Container, typename Value> friend class internal::concurrent_queue_iterator;
#endif 

public:
    explicit concurrent_queue(const A& a = A()) : 
        concurrent_bounded_queue<T,A>( a )
    {
    }

    concurrent_queue( const concurrent_queue& src, const A& a = A()) : 
        concurrent_bounded_queue<T,A>( src, a )
    {
    }

    template<typename InputIterator>
    concurrent_queue( InputIterator b /*begin*/, InputIterator e /*end*/, const A& a = A()) :
        concurrent_bounded_queue<T,A>( b, e, a )
    {
    }


    bool push_if_not_full( const T& source ) {
        return try_push( source );
    }


    bool pop_if_present( T& destination ) {
        return try_pop( destination );
    }

    typedef typename concurrent_bounded_queue<T,A>::iterator iterator;
    typedef typename concurrent_bounded_queue<T,A>::const_iterator const_iterator;
    //
    //------------------------------------------------------------------------
    // The iterators are intended only for debugging.  They are slow and not thread safe.
    //------------------------------------------------------------------------
    iterator begin() {return this->unsafe_begin();}
    iterator end() {return this->unsafe_end();}
    const_iterator begin() const {return this->unsafe_begin();}
    const_iterator end() const {return this->unsafe_end();}
}; 

}
    

#if TBB_DEPRECATED
using deprecated::concurrent_queue;
#else
using strict_ppl::concurrent_queue;    
#endif

} // namespace tbb

#endif /* __TBB_concurrent_queue_H */