Boost C++ Libraries

...one of the most highly regarded and expertly designed C++ library projects in the world. Herb Sutter and Andrei Alexandrescu, C++ Coding Standards

This is the documentation for an old version of boost. Click here for the latest Boost documentation.

boost/filesystem/convenience.hpp

//  boost/filesystem/convenience.hpp  ----------------------------------------//

//  Copyright Beman Dawes, 2002-2005
//  Copyright Vladimir Prus, 2002
//  Use, modification, and distribution is subject to the Boost Software
//  License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
//  http://www.boost.org/LICENSE_1_0.txt)

//  See library home page at http://www.boost.org/libs/filesystem

//----------------------------------------------------------------------------// 

#ifndef BOOST_FILESYSTEM_CONVENIENCE_HPP
#define BOOST_FILESYSTEM_CONVENIENCE_HPP

#include <boost/filesystem/operations.hpp>
#include <vector>
#include <stack>

#include <boost/config/abi_prefix.hpp> // must be the last #include

# ifndef BOOST_FILESYSTEM_NARROW_ONLY
#   define BOOST_FS_FUNC(BOOST_FS_TYPE) \
      template<class Path> typename boost::enable_if<is_basic_path<Path>, \
      BOOST_FS_TYPE>::type
#   define BOOST_FS_FUNC_STRING BOOST_FS_FUNC(typename Path::string_type)
#   define BOOST_FS_TYPENAME typename
# else
#   define BOOST_FS_FUNC(BOOST_FS_TYPE) inline BOOST_FS_TYPE 
    typedef boost::filesystem::path Path;
#   define BOOST_FS_FUNC_STRING std::string
#   define BOOST_FS_TYPENAME
# endif

namespace boost
{
  namespace filesystem
  {

    BOOST_FS_FUNC(bool) create_directories(const Path& ph)
    {
         if (ph.empty() || exists(ph))
         {
           if ( !ph.empty() && !is_directory(ph) )
               boost::throw_exception( basic_filesystem_error<Path>(
                 "boost::filesystem::create_directories", ph, -1 ) );
           return false;
         }

         // First create branch, by calling ourself recursively
         create_directories(ph.branch_path());
         // Now that parent's path exists, create the directory
         create_directory(ph);
         return true;
     }

    BOOST_FS_FUNC_STRING extension(const Path& ph)
    {
      typedef BOOST_FS_TYPENAME Path::string_type string_type;
      string_type leaf = ph.leaf();

      BOOST_FS_TYPENAME string_type::size_type n = leaf.rfind('.');
      if (n != string_type::npos)
        return leaf.substr(n);
      else
        return string_type();
    }

    BOOST_FS_FUNC_STRING basename(const Path& ph)
    {
      typedef BOOST_FS_TYPENAME Path::string_type string_type;
      string_type leaf = ph.leaf();
      BOOST_FS_TYPENAME string_type::size_type n = leaf.rfind('.');
      return leaf.substr(0, n);
    }

    BOOST_FS_FUNC(Path) change_extension( const Path & ph,
      const BOOST_FS_TYPENAME Path::string_type & new_extension )
      { return ph.branch_path() / (basename(ph) + new_extension); }

# ifndef BOOST_FILESYSTEM_NARROW_ONLY

    // "do-the-right-thing" overloads  ---------------------------------------//

    inline bool create_directories(const path& ph)
      { return create_directories<path>(ph); }
    inline bool create_directories(const wpath& ph)
      { return create_directories<wpath>(ph); }

    inline std::string extension(const path& ph)
      { return extension<path>(ph); }
    inline std::wstring extension(const wpath& ph)
      { return extension<wpath>(ph); }

    inline std::string basename(const path& ph)
      { return basename<path>( ph ); }
    inline std::wstring basename(const wpath& ph)
      { return basename<wpath>( ph ); }

    inline path change_extension( const path & ph, const std::string& new_ex )
      { return change_extension<path>( ph, new_ex ); }
    inline wpath change_extension( const wpath & ph, const std::wstring& new_ex )
      { return change_extension<wpath>( ph, new_ex ); }

# endif


    //  basic_recursive_directory_iterator helpers  --------------------------//

    namespace detail
    {
      template< class Path >
      struct recur_dir_itr_imp
      {
        typedef basic_directory_iterator< Path > element_type;
        std::stack< element_type, std::vector< element_type > > m_stack;
        int  m_level;
        bool m_no_push;
        bool m_no_throw;

        recur_dir_itr_imp() : m_level(0), m_no_push(false), m_no_throw(false) {}
      };

    } // namespace detail

    //  basic_recursive_directory_iterator  ----------------------------------//

    template< class Path >
    class basic_recursive_directory_iterator
      : public boost::iterator_facade<
          basic_recursive_directory_iterator<Path>,
          basic_directory_entry<Path>,
          boost::single_pass_traversal_tag >
    {
    public:
      typedef Path path_type;

      basic_recursive_directory_iterator(){}  // creates the "end" iterator

      explicit basic_recursive_directory_iterator( const Path & dir_path );
      basic_recursive_directory_iterator( const Path & dir_path, system_error_type & ec );

      int level() const { return m_imp->m_level; }

      void pop();
      void no_push()
      {
        BOOST_ASSERT( m_imp.get() && "attempt to no_push() on end iterator" );
        m_imp->m_no_push = true;
      }

      file_status status() const
      {
        BOOST_ASSERT( m_imp.get()
          && "attempt to call status() on end recursive_iterator" );
        return m_imp->m_stack.top()->status();
      }

      file_status symlink_status() const
      {
        BOOST_ASSERT( m_imp.get()
          && "attempt to call symlink_status() on end recursive_iterator" );
        return m_imp->m_stack.top()->symlink_status();
      }

    private:

      // shared_ptr provides shallow-copy semantics required for InputIterators.
      // m_imp.get()==0 indicates the end iterator.
      boost::shared_ptr< detail::recur_dir_itr_imp< Path > >  m_imp;

      friend class boost::iterator_core_access;

      typename boost::iterator_facade< 
        basic_recursive_directory_iterator<Path>,
        basic_directory_entry<Path>,
        boost::single_pass_traversal_tag >::reference
      dereference() const 
      {
        BOOST_ASSERT( m_imp.get() && "attempt to dereference end iterator" );
        return *m_imp->m_stack.top();
      }

      void increment();

      bool equal( const basic_recursive_directory_iterator & rhs ) const
        { return m_imp == rhs.m_imp; }
    };

    typedef basic_recursive_directory_iterator<path> recursive_directory_iterator;
# ifndef BOOST_FILESYSTEM_NARROW_ONLY
    typedef basic_recursive_directory_iterator<wpath> wrecursive_directory_iterator;
# endif

    //  basic_recursive_directory_iterator implementation  -------------------//

    //  constructors
    template<class Path>
    basic_recursive_directory_iterator<Path>::
      basic_recursive_directory_iterator( const Path & dir_path )
      : m_imp( new detail::recur_dir_itr_imp<Path> )
    {
      m_imp->m_stack.push( basic_directory_iterator<Path>( dir_path ) );
    }

    template<class Path>
    basic_recursive_directory_iterator<Path>::
      basic_recursive_directory_iterator( const Path & dir_path, system_error_type & ec )
      : m_imp( new detail::recur_dir_itr_imp<Path> )
    {
      m_imp->m_stack.push( basic_directory_iterator<Path>( dir_path, std::nothrow ) );
      m_imp->m_no_throw = true;
    }

    //  increment
    template<class Path>
    void basic_recursive_directory_iterator<Path>::increment()
    {
      BOOST_ASSERT( m_imp.get() && "increment on end iterator" );
      
      static const basic_directory_iterator<Path> end_itr;

      if ( m_imp->m_no_push ) m_imp->m_no_push = false;
      else if ( is_directory( m_imp->m_stack.top()->status() ) )
      {
        system_error_type ec;
        m_imp->m_stack.push(
          m_imp->m_no_throw
            ? basic_directory_iterator<Path>( *m_imp->m_stack.top(), ec )
            : basic_directory_iterator<Path>( *m_imp->m_stack.top() )
          );
        if ( m_imp->m_stack.top() != end_itr )
        {
          ++m_imp->m_level;
          return;
        }
        m_imp->m_stack.pop();
      }

      while ( !m_imp->m_stack.empty()
        && ++m_imp->m_stack.top() == end_itr )
      {
        m_imp->m_stack.pop();
        --m_imp->m_level;
      }

      if ( m_imp->m_stack.empty() ) m_imp.reset(); // done, so make end iterator
    }

    //  pop
    template<class Path>
    void basic_recursive_directory_iterator<Path>::pop()
    {
      BOOST_ASSERT( m_imp.get() && "pop on end iterator" );
      BOOST_ASSERT( m_imp->m_level > 0 && "pop with level < 1" );

      m_imp->m_stack.pop();
      --m_imp->m_level;
    }

    //  what() basic_filesystem_error_decoder  -------------------------------//

    namespace detail
    {

#   if BOOST_WORKAROUND(__BORLANDC__,BOOST_TESTED_AT(0x581))
      using boost::filesystem::system_message;
#   endif

      inline void decode_system_message( system_error_type ec, std::string & target )
      {
        system_message( ec, target );
      }

#   if defined(BOOST_WINDOWS_API) && !defined(BOOST_FILESYSTEM_NARROW_ONLY)
      inline void decode_system_message( system_error_type ec, std::wstring & target )
      {
        system_message( ec, target );
      }
#   endif

      template<class String>
      void decode_system_message( system_error_type ec, String & target )
      {
        std::string temp;
        system_message( ec, temp );
        for ( const char * p = temp.c_str(); *p != 0; ++p )
          { target += static_cast<typename String::value_type>( *p ); }
      }
    }

    template<class Path>
    typename Path::string_type what( const basic_filesystem_error<Path> & ex )
    {
      typename Path::string_type s;
      for ( const char * p = ex.what(); *p != 0; ++p )
        { s += static_cast<typename Path::string_type::value_type>( *p ); }

      if ( !ex.path1().empty() )
      {
        s += static_cast<typename Path::string_type::value_type>( ':' );
        s += static_cast<typename Path::string_type::value_type>( ' ' );
        s += static_cast<typename Path::string_type::value_type>( '\"' );
        s += ex.path1().file_string();
        s += static_cast<typename Path::string_type::value_type>( '\"' );
      }
      if ( !ex.path2().empty() )
      {
        s += static_cast<typename Path::string_type::value_type>( ',' );
        s += static_cast<typename Path::string_type::value_type>( ' ' );
        s += static_cast<typename Path::string_type::value_type>( '\"' );
        s += ex.path2().file_string();
        s += static_cast<typename Path::string_type::value_type>( '\"' );
      }
      if ( ex.system_error() )
      {
        s += static_cast<typename Path::string_type::value_type>( ' ' );

        detail::decode_system_message( ex.system_error(), s );
      }
      return s;
    }

  } // namespace filesystem
} // namespace boost

#undef BOOST_FS_FUNC_STRING
#undef BOOST_FS_FUNC

#include <boost/config/abi_suffix.hpp> // pops abi_prefix.hpp pragmas
#endif // BOOST_FILESYSTEM_CONVENIENCE_HPP