findvolume_sequence.hpp

用STL的方式封装了WindowsAPI、COM调用、ACE、ATL、MFC、WTL等多种组件

/* /////////////////////////////////////////////////////////////////////////
 * File:        winstl/filesystem/findvolume_sequence.hpp (formerly winstl_findvolume_sequence.h)
 *
 * Purpose:     Contains the basic_findvolume_sequence template class, and ANSI
 *              and Unicode specialisations thereof.
 *
 * Notes:       The original implementation of the class had the const_iterator
 *              and value_type as nested classes. Unfortunately, Visual C++ 5 &
 *              6 both had either compilation or linking problems so these are
 *              regretably now implemented as independent classes.
 *
 * Created:     15th January 2002
 * Updated:     10th June 2006
 *
 * Home:        http://stlsoft.org/
 *
 * Copyright (c) 2002-2006, Matthew Wilson and Synesis Software
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * - Redistributions of source code must retain the above copyright notice, this
 *   list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright notice,
 *   this list of conditions and the following disclaimer in the documentation
 *   and/or other materials provided with the distribution.
 * - Neither the name(s) of Matthew Wilson and Synesis Software nor the names of
 *   any contributors may be used to endorse or promote products derived from
 *   this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 * ////////////////////////////////////////////////////////////////////// */


/** \file winstl/filesystem/findvolume_sequence.hpp
 *
 * \brief [C++ only] Definition of the winstl::basic_findvolume_sequence
 *  class template.
 *  (\ref group__library__file_system "File System" Library.)
 */

#ifndef WINSTL_INCL_WINSTL_FILESYSTEM_HPP_FINDVOLUME_SEQUENCE
#define WINSTL_INCL_WINSTL_FILESYSTEM_HPP_FINDVOLUME_SEQUENCE

#ifndef STLSOFT_DOCUMENTATION_SKIP_SECTION
# define WINSTL_VER_WINSTL_FILESYSTEM_HPP_FINDVOLUME_SEQUENCE_MAJOR     4
# define WINSTL_VER_WINSTL_FILESYSTEM_HPP_FINDVOLUME_SEQUENCE_MINOR     1
# define WINSTL_VER_WINSTL_FILESYSTEM_HPP_FINDVOLUME_SEQUENCE_REVISION  2
# define WINSTL_VER_WINSTL_FILESYSTEM_HPP_FINDVOLUME_SEQUENCE_EDIT      92
#endif /* !STLSOFT_DOCUMENTATION_SKIP_SECTION */

/* /////////////////////////////////////////////////////////////////////////
 * Includes
 */

#ifndef WINSTL_INCL_WINSTL_H_WINSTL
# include <winstl/winstl.h>
#endif /* !WINSTL_INCL_WINSTL_H_WINSTL */
#ifndef WINSTL_INCL_WINSTL_FILESYSTEM_HPP_FILESYSTEM_TRAITS
# include <winstl/filesystem/filesystem_traits.hpp>
#endif /* !WINSTL_INCL_WINSTL_FILESYSTEM_HPP_FILESYSTEM_TRAITS */
#ifndef STLSOFT_INCL_STLSOFT_HPP_ITERATOR
# include <stlsoft/iterator.hpp>
#endif /* !STLSOFT_INCL_STLSOFT_HPP_ITERATOR */
#ifndef STLSOFT_INCL_STLSOFT_COLLECTIONS_HPP_COLLECTIONS
# include <stlsoft/collections/collections.hpp>
#endif /* !STLSOFT_INCL_STLSOFT_COLLECTIONS_HPP_COLLECTIONS */

/* /////////////////////////////////////////////////////////////////////////
 * Namespace
 */

#ifndef _WINSTL_NO_NAMESPACE
# if defined(_STLSOFT_NO_NAMESPACE) || \
     defined(STLSOFT_DOCUMENTATION_SKIP_SECTION)
/* There is no stlsoft namespace, so must define ::winstl */
namespace winstl
{
# else
/* Define stlsoft::winstl_project */

namespace stlsoft
{

namespace winstl_project
{

# endif /* _STLSOFT_NO_NAMESPACE */
#endif /* !_WINSTL_NO_NAMESPACE */

/* /////////////////////////////////////////////////////////////////////////
 * Enumerations
 */

// The FindNextVolume API is not well documented so assume _MAX_PATH
// is sufficient for volume names
enum
{
    MAX_VOL_NAME    =   _MAX_PATH   //!< The maximum number of characters in a volume name
};

/* /////////////////////////////////////////////////////////////////////////
 * Forward declarations
 */

#ifndef STLSOFT_DOCUMENTATION_SKIP_SECTION

template <ss_typename_param_k C, ss_typename_param_k T>
class basic_findvolume_sequence_value_type;

template <ss_typename_param_k C, ss_typename_param_k T, ss_typename_param_k V>
class basic_findvolume_sequence_const_iterator;

#endif /* !STLSOFT_DOCUMENTATION_SKIP_SECTION */

/* /////////////////////////////////////////////////////////////////////////
 * Classes
 */

// class basic_findvolume_sequence
/// \brief Presents an STL-like sequence interface over the volumes on a system
///
/// \ingroup group__library__file_system
///
/// \note This class functions only on Windows 2000 and later
///
/// \param C The character type
/// \param T The traits type. On translators that support default template arguments this defaults to filesystem_traits<C>
template<   ss_typename_param_k C
#ifdef STLSOFT_CF_TEMPLATE_CLASS_DEFAULT_CLASS_ARGUMENT_SUPPORT
        ,   ss_typename_param_k T = filesystem_traits<C>
#else /* ? STLSOFT_CF_TEMPLATE_CLASS_DEFAULT_CLASS_ARGUMENT_SUPPORT */
        ,   ss_typename_param_k T /* = filesystem_traits<C> */
#endif /* STLSOFT_CF_TEMPLATE_CLASS_DEFAULT_CLASS_ARGUMENT_SUPPORT */
        >
class basic_findvolume_sequence
    : public stlsoft_ns_qual(stl_collection_tag)
{
public:
    /// The character type
    typedef C                                                           char_type;
    /// The traits type
    typedef T                                                           traits_type;
    /// The current parameterisation of the type
    typedef basic_findvolume_sequence<C, T>                             class_type;
    /// The value type
    typedef basic_findvolume_sequence_value_type<C, T>                  value_type;
    /// The non-mutating (const) iterator type
    typedef basic_findvolume_sequence_const_iterator<C, T, value_type>  const_iterator;
    /// The reference type
    typedef value_type                                                  &reference;
    /// The non-mutable (const) reference type
    typedef const value_type                                            &const_reference;

// Iteration
public:
    /// Begins the iteration
    ///
    /// \return An iterator representing the start of the sequence
    const_iterator  begin() const;
    /// Ends the iteration
    ///
    /// \return An iterator representing the end of the sequence
    const_iterator  end() const;

// State
public:
    /// Evalulates whether the sequence is empty
    ws_bool_t       empty() const;
};

/* /////////////////////////////////////////////////////////////////////////
 * Typedefs for commonly encountered types
 */

/// Instantiation of the basic_findvolume_sequence template for the ANSI character type \c char
typedef basic_findvolume_sequence<ws_char_a_t, filesystem_traits<ws_char_a_t> >     findvolume_sequence_a;
/// Instantiation of the basic_findvolume_sequence template for the Unicode character type \c wchar_t
typedef basic_findvolume_sequence<ws_char_w_t, filesystem_traits<ws_char_w_t> >     findvolume_sequence_w;
/// Instantiation of the basic_findvolume_sequence template for the Win32 character type \c TCHAR
typedef basic_findvolume_sequence<TCHAR, filesystem_traits<TCHAR> >                 findvolume_sequence;

/* ////////////////////////////////////////////////////////////////////// */

// class basic_findvolume_sequence_value_type
/// Value type for the basic_findvolume_sequence
template<   ss_typename_param_k C
        ,   ss_typename_param_k T
        >
class basic_findvolume_sequence_value_type
{
public:
    /// The character type
    typedef C                                           char_type;
    /// The traits type
    typedef T                                           traits_type;
    /// The current parameterisation of the type
    typedef basic_findvolume_sequence_value_type<C, T>  class_type;

public:
    /// Default constructor
    basic_findvolume_sequence_value_type();
    /// Copy constructor
    basic_findvolume_sequence_value_type(class_type const &rhs);
private:
    basic_findvolume_sequence_value_type(char_type const *vol_name);
public:

    /// Copy assignment operator
    class_type &operator =(class_type const &rhs);

// Attributes
public:
    /// Implicit conversion to non-mutable pointer-to-const of the volume name
    operator char_type const * () const
    {
        return m_name;
    }

private:
    friend class basic_findvolume_sequence_const_iterator<C, T, class_type>;

    char_type   m_name[MAX_VOL_NAME + 1];
};

// class basic_findvolume_sequence_const_iterator
/// Iterator type for the basic_findvolume_sequence, supporting the Input Iterator concept
template<   ss_typename_param_k C
        ,   ss_typename_param_k T
        ,   ss_typename_param_k V
        >
class basic_findvolume_sequence_const_iterator
    : public stlsoft_ns_qual(iterator_base)<winstl_ns_qual_std(input_iterator_tag)
                                        ,   V
                                        ,   ws_ptrdiff_t
                                        ,   void    // By-Value Temporary reference
                                        ,   V       // By-Value Temporary reference
                                        >
{
public:
    /// The character type
    typedef C                                                   char_type;
    /// The traits type
    typedef T                                                   traits_type;
    /// The traits type
    typedef V                                                   value_type;
    /// The current parameterisation of the type
    typedef basic_findvolume_sequence_const_iterator<C, T, V>   class_type;

/// \name Utility classes
/// @{
private:
#ifndef STLSOFT_DOCUMENTATION_SKIP_SECTION
    struct shared_handle
    {
    public:
        typedef shared_handle       class_type;

    // Members
    public:
        HANDLE      hSrch;
    private:
        ss_sint32_t cRefs;

    public:
        ss_explicit_k shared_handle(HANDLE h)
            : hSrch(h)
            , cRefs(1)
        {}
        void AddRef()
        {
            ++cRefs;
        }
        void Release()
        {
            if(0 == --cRefs)
            {
                delete this;
            }
        }
    #if defined(STLSOFT_CF_COMPILER_WARNS_NO_PUBLIC_DTOR)
    protected:
    #else /* ? STLSOFT_CF_COMPILER_WARNS_NO_PUBLIC_DTOR */
    private:
    #endif /* STLSOFT_CF_COMPILER_WARNS_NO_PUBLIC_DTOR */
        ~shared_handle() stlsoft_throw_0()
        {
            WINSTL_MESSAGE_ASSERT("Shared search handle being destroyed with outstanding references!", 0 == cRefs);

            if(hSrch != INVALID_HANDLE_VALUE)
            {
                traits_type::find_volume_close(hSrch);
            }
        }

    private:
        shared_handle(class_type const &);
        class_type &operator =(class_type const &);
    };
#endif /* !STLSOFT_DOCUMENTATION_SKIP_SECTION */
/// @}

/// \name Construction
/// @{
private:
    basic_findvolume_sequence_const_iterator(basic_findvolume_sequence<C, T> const &l, HANDLE hSrch, char_type const *vol_name)
        : m_list(&l)
        , m_handle(new shared_handle(hSrch))
    {
        WINSTL_ASSERT(INVALID_HANDLE_VALUE != hSrch);

        if(NULL == m_handle)
        {
            traits_type::find_volume_close(hSrch);
            m_name[0] = '\0';
        }
        else
        {
            traits_type::str_copy(m_name, vol_name);
        }
    }
    basic_findvolume_sequence_const_iterator(basic_findvolume_sequence<C, T> const &l);
public:
    /// Default constructor
    basic_findvolume_sequence_const_iterator();
    /// Copy constructor
    basic_findvolume_sequence_const_iterator(class_type const &rhs);
    /// Destructor
    ~basic_findvolume_sequence_const_iterator() stlsoft_throw_0();

    /// Copy assignment operator
    class_type &operator =(class_type const &rhs);

public:
    /// Pre-increment operator
    class_type &operator ++();
    /// Post-increment operator
    class_type operator ++(int);
    /// Dereference to access the value at the current position