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

//
// RecursiveDirectoryIteratorStategies.h
//
// Library: Foundation
// Package: Filesystem
// Module:  RecursiveDirectoryIterator
//
// Definitions of the RecursiveDirectoryIterator strategy classes.
//
// Copyright (c) 2012, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// SPDX-License-Identifier:	BSL-1.0
//


#ifndef Foundation_RecursiveDirectoryIteratorStrategy_INCLUDED
#define Foundation_RecursiveDirectoryIteratorStrategy_INCLUDED


#include <functional>
#include <queue>
#include <stack>
#include "Poco/DirectoryIterator.h"
#include "Poco/Foundation.h"


namespace Poco
{


class Foundation_API TraverseBase
{
public:
    typedef std::stack<DirectoryIterator> Stack;
    typedef std::function<UInt16(const Stack &)> DepthFunPtr;

    enum
    {
        D_INFINITE = 0 /// Special value for infinite traverse depth.
    };

    TraverseBase(DepthFunPtr depthDeterminer, UInt16 maxDepth = D_INFINITE);

protected:
    bool isFiniteDepth();
    bool isDirectory(Poco::File & file);

    DepthFunPtr _depthDeterminer;
    UInt16 _maxDepth;
    DirectoryIterator _itEnd;

private:
    TraverseBase();
    TraverseBase(const TraverseBase &);
    TraverseBase & operator=(const TraverseBase &);
};


class Foundation_API ChildrenFirstTraverse : public TraverseBase
{
public:
    ChildrenFirstTraverse(DepthFunPtr depthDeterminer, UInt16 maxDepth = D_INFINITE);

    const std::string next(Stack * itStack, bool * isFinished);

private:
    ChildrenFirstTraverse();
    ChildrenFirstTraverse(const ChildrenFirstTraverse &);
    ChildrenFirstTraverse & operator=(const ChildrenFirstTraverse &);
};


class Foundation_API SiblingsFirstTraverse : public TraverseBase
{
public:
    SiblingsFirstTraverse(DepthFunPtr depthDeterminer, UInt16 maxDepth = D_INFINITE);

    const std::string next(Stack * itStack, bool * isFinished);

private:
    SiblingsFirstTraverse();
    SiblingsFirstTraverse(const SiblingsFirstTraverse &);
    SiblingsFirstTraverse & operator=(const SiblingsFirstTraverse &);

    std::stack<std::queue<std::string>> _dirsStack;
};


} // namespace Poco


#endif // Foundation_RecursiveDirectoryIteratorStrategy_INCLUDED