xref: /freebsd-11-stable/contrib/llvm-project/lldb/include/lldb/Utility/Iterable.h

//===-- Iterable.h ----------------------------------------------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

#ifndef liblldb_Iterable_h_
#define liblldb_Iterable_h_

#include "lldb/Host/Mutex.h"

namespace lldb_private
{

template <typename I, typename E> E map_adapter(I &iter)
{
    return iter->second;
}

template <typename I, typename E> E vector_adapter(I &iter)
{
    return *iter;
}

template <typename C, typename E, E (*A)(typename C::const_iterator &)> class AdaptedConstIterator
{
public:
    typedef typename C::const_iterator BackingIterator;
private:
    BackingIterator m_iter;
public:
    // Wrapping constructor
    AdaptedConstIterator (BackingIterator backing_iterator) :
        m_iter(backing_iterator)
    {
    }

    // Default-constructible
    AdaptedConstIterator () :
        m_iter()
    {
    }

    // Copy-constructible
    AdaptedConstIterator (const AdaptedConstIterator &rhs) :
        m_iter(rhs.m_iter)
    {
    }

    // Copy-assignable
    AdaptedConstIterator &operator= (const AdaptedConstIterator &rhs)
    {
        m_iter = rhs.m_iter;
        return *this;
    }

    // Destructible
    ~AdaptedConstIterator () { }

    // Comparable
    bool operator== (const AdaptedConstIterator &rhs)
    {
        return m_iter == rhs.m_iter;
    }

    bool operator!= (const AdaptedConstIterator &rhs)
    {
        return m_iter != rhs.m_iter;
    }

    // Rvalue dereferenceable
    E operator* ()
    {
        return (*A)(m_iter);
    }

    E operator-> ()
    {
        return (*A)(m_iter);
    }

    // Offset dereferenceable
    E operator[] (typename BackingIterator::difference_type offset)
    {
        return AdaptedConstIterator(m_iter + offset);
    }

    // Incrementable
    AdaptedConstIterator &operator++ ()
    {
        m_iter++;
        return *this;
    }

    // Decrementable
    AdaptedConstIterator &operator-- ()
    {
        m_iter--;
        return *this;
    }

    // Compound assignment
    AdaptedConstIterator &operator+= (typename BackingIterator::difference_type offset)
    {
        m_iter += offset;
        return *this;
    }

    AdaptedConstIterator &operator-= (typename BackingIterator::difference_type offset)
    {
        m_iter -= offset;
        return *this;
    }

    // Arithmetic
    AdaptedConstIterator operator+ (typename BackingIterator::difference_type offset)
    {
        return AdaptedConstIterator(m_iter + offset);
    }

    AdaptedConstIterator operator- (typename BackingIterator::difference_type offset)
    {
        return AdaptedConstIterator(m_iter - offset);
    }

    // Comparable
    bool operator< (AdaptedConstIterator &rhs)
    {
        return m_iter < rhs.m_iter;
    }

    bool operator<= (AdaptedConstIterator &rhs)
    {
        return m_iter <= rhs.m_iter;
    }

    bool operator> (AdaptedConstIterator &rhs)
    {
        return m_iter > rhs.m_iter;
    }

    bool operator>= (AdaptedConstIterator &rhs)
    {
        return m_iter >= rhs.m_iter;
    }

    friend AdaptedConstIterator operator+(typename BackingIterator::difference_type, AdaptedConstIterator &);
    friend typename BackingIterator::difference_type operator-(AdaptedConstIterator &, AdaptedConstIterator &);
    friend void swap(AdaptedConstIterator &, AdaptedConstIterator &);
};

template <typename C, typename E, E (*A)(typename C::const_iterator &)>
AdaptedConstIterator<C, E, A> operator+ (typename AdaptedConstIterator<C, E, A>::BackingIterator::difference_type offset, AdaptedConstIterator<C, E, A> &rhs)
{
    return rhs.operator+(offset);
}

template <typename C, typename E, E (*A)(typename C::const_iterator &)>
typename AdaptedConstIterator<C, E, A>::BackingIterator::difference_type operator- (AdaptedConstIterator<C, E, A> &lhs, AdaptedConstIterator<C, E, A> &rhs)
{
    return(lhs.m_iter - rhs.m_iter);
}

template <typename C, typename E, E (*A)(typename C::const_iterator &)>
void swap (AdaptedConstIterator<C, E, A> &lhs, AdaptedConstIterator<C, E, A> &rhs)
{
    std::swap(lhs.m_iter, rhs.m_iter);
}

template <typename C, typename E, E (*A)(typename C::const_iterator &)> class AdaptedIterable
{
private:
    const C &m_container;
public:
    AdaptedIterable (const C &container) :
        m_container(container)
    {
    }

    AdaptedConstIterator<C, E, A> begin ()
    {
        return AdaptedConstIterator<C, E, A>(m_container.begin());
    }

    AdaptedConstIterator<C, E, A> end ()
    {
        return AdaptedConstIterator<C, E, A>(m_container.end());
    }
};

template <typename C, typename E, E (*A)(typename C::const_iterator &)> class LockingAdaptedIterable : public AdaptedIterable<C, E, A>
{
private:
    Mutex *m_mutex = nullptr;
public:
    LockingAdaptedIterable (C &container, Mutex &mutex) :
        AdaptedIterable<C,E,A>(container),
        m_mutex(&mutex)
    {
        m_mutex->Lock();
    }

    LockingAdaptedIterable (LockingAdaptedIterable &&rhs) :
        AdaptedIterable<C,E,A>(rhs),
        m_mutex(rhs.m_mutex)
    {
        rhs.m_mutex = NULL;
    }

    ~LockingAdaptedIterable ()
    {
        if (m_mutex)
            m_mutex->Unlock();
    }

private:
    DISALLOW_COPY_AND_ASSIGN(LockingAdaptedIterable);
};

}

#endif