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

//
// Path.h
//
// Library: Foundation
// Package: Filesystem
// Module:  Path
//
// Definition of the Path class.
//
// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// SPDX-License-Identifier:	BSL-1.0
//


#ifndef Foundation_Path_INCLUDED
#define Foundation_Path_INCLUDED


#include <vector>
#include "Poco/Foundation.h"


namespace Poco
{


class Foundation_API Path
/// This class represents filesystem paths in a
/// platform-independent manner.
/// Unix, Windows and OpenVMS all use a different
/// syntax for filesystem paths.
/// This class can work with all three formats.
/// A path is made up of an optional node name
/// (only Windows and OpenVMS), an optional
/// device name (also only Windows and OpenVMS),
/// a list of directory names and an optional
/// filename.
{
public:
    enum Style
    {
        PATH_UNIX, /// Unix-style path
        PATH_WINDOWS, /// Windows-style path
        PATH_VMS, /// VMS-style path
        PATH_NATIVE, /// The current platform's native style
        PATH_GUESS /// Guess the style by examining the path
    };

    typedef std::vector<std::string> StringVec;

    Path();
    /// Creates an empty relative path.

    Path(bool absolute);
    /// Creates an empty absolute or relative path.

    Path(const char * path);
    /// Creates a path from a string.

    Path(const char * path, Style style);
    /// Creates a path from a string.

    Path(const std::string & path);
    /// Creates a path from a string.

    Path(const std::string & path, Style style);
    /// Creates a path from a string.

    Path(const Path & path);
    /// Copy constructor

    Path(const Path & parent, const std::string & fileName);
    /// Creates a path from a parent path and a filename.
    /// The parent path is expected to reference a directory.

    Path(const Path & parent, const char * fileName);
    /// Creates a path from a parent path and a filename.
    /// The parent path is expected to reference a directory.

    Path(const Path & parent, const Path & relative);
    /// Creates a path from a parent path and a relative path.
    /// The parent path is expected to reference a directory.
    /// The relative path is appended to the parent path.

    ~Path();
    /// Destroys the Path.

    Path & operator=(const Path & path);
    /// Assignment operator.

    Path & operator=(const std::string & path);
    /// Assigns a string containing a path in native format.

    Path & operator=(const char * path);
    /// Assigns a string containing a path in native format.

    void swap(Path & path);
    /// Swaps the path with another one.

    Path & assign(const std::string & path);
    /// Assigns a string containing a path in native format.

    Path & assign(const std::string & path, Style style);
    /// Assigns a string containing a path.

    Path & assign(const Path & path);
    /// Assigns the given path.

    Path & assign(const char * path);
    /// Assigns a string containing a path.

    std::string toString() const;
    /// Returns a string containing the path in native format.

    std::string toString(Style style) const;
    /// Returns a string containing the path in the given format.

    Path & parse(const std::string & path);
    /// Same as assign().

    Path & parse(const std::string & path, Style style);
    /// Assigns a string containing a path.

    bool tryParse(const std::string & path);
    /// Tries to interpret the given string as a path
    /// in native format.
    /// If the path is syntactically valid, assigns the
    /// path and returns true. Otherwise leaves the
    /// object unchanged and returns false.

    bool tryParse(const std::string & path, Style style);
    /// Tries to interpret the given string as a path,
    /// according to the given style.
    /// If the path is syntactically valid, assigns the
    /// path and returns true. Otherwise leaves the
    /// object unchanged and returns false.

    Path & parseDirectory(const std::string & path);
    /// The resulting path always refers to a directory and
    /// the filename part is empty.

    Path & parseDirectory(const std::string & path, Style style);
    /// The resulting path always refers to a directory and
    /// the filename part is empty.

    Path & makeDirectory();
    /// If the path contains a filename, the filename is appended
    /// to the directory list and cleared. Thus the resulting path
    /// always refers to a directory.

    Path & makeFile();
    /// If the path contains no filename, the last directory
    /// becomes the filename.

    Path & makeParent();
    /// Makes the path refer to its parent.

    Path & makeAbsolute();
    /// Makes the path absolute if it is relative.
    /// The current working directory is taken as base directory.

    Path & makeAbsolute(const Path & base);
    /// Makes the path absolute if it is relative.
    /// The given path is taken as base.

    Path & append(const Path & path);
    /// Appends the given path.

    Path & resolve(const Path & path);
    /// Resolves the given path against the current one.
    ///
    /// If the given path is absolute, it replaces the current one.
    /// Otherwise, the relative path is appended to the current path.

    bool isAbsolute() const;
    /// Returns true iff the path is absolute.

    bool isRelative() const;
    /// Returns true iff the path is relative.

    bool isDirectory() const;
    /// Returns true iff the path references a directory
    /// (the filename part is empty).

    bool isFile() const;
    /// Returns true iff the path references a file
    /// (the filename part is not empty).

    Path & setNode(const std::string & node);
    /// Sets the node name.
    /// Setting a non-empty node automatically makes
    /// the path an absolute one.

    const std::string & getNode() const;
    /// Returns the node name.

    Path & setDevice(const std::string & device);
    /// Sets the device name.
    /// Setting a non-empty device automatically makes
    /// the path an absolute one.

    const std::string & getDevice() const;
    /// Returns the device name.

    int depth() const;
    /// Returns the number of directories in the directory list.

    const std::string & directory(int n) const;
    /// Returns the n'th directory in the directory list.
    /// If n == depth(), returns the filename.

    const std::string & operator[](int n) const;
    /// Returns the n'th directory in the directory list.
    /// If n == depth(), returns the filename.

    Path & pushDirectory(const std::string & dir);
    /// Adds a directory to the directory list.

    Path & popDirectory();
    /// Removes the last directory from the directory list.

    Path & popFrontDirectory();
    /// Removes the first directory from the directory list.

    Path & setFileName(const std::string & name);
    /// Sets the filename.

    const std::string & getFileName() const;
    /// Returns the filename.

    Path & setBaseName(const std::string & name);
    /// Sets the basename part of the filename and
    /// does not change the extension.

    std::string getBaseName() const;
    /// Returns the basename (the filename sans
    /// extension) of the path.

    Path & setExtension(const std::string & extension);
    /// Sets the filename extension.

    std::string getExtension() const;
    /// Returns the filename extension.

    const std::string & version() const;
    /// Returns the file version. VMS only.

    Path & clear();
    /// Clears all components.

    Path parent() const;
    /// Returns a path referring to the path's
    /// directory.

    Path absolute() const;
    /// Returns an absolute variant of the path,
    /// taking the current working directory as base.

    Path absolute(const Path & base) const;
    /// Returns an absolute variant of the path,
    /// taking the given path as base.

    static Path forDirectory(const std::string & path);
    /// Creates a path referring to a directory.

    static Path forDirectory(const std::string & path, Style style);
    /// Creates a path referring to a directory.

    static char separator();
    /// Returns the platform's path name separator, which separates
    /// the components (names) in a path.
    ///
    /// On Unix systems, this is the slash '/'. On Windows systems,
    /// this is the backslash '\'. On OpenVMS systems, this is the
    /// period '.'.

    static char pathSeparator();
    /// Returns the platform's path separator, which separates
    /// single paths in a list of paths.
    ///
    /// On Unix systems, this is the colon ':'. On Windows systems,
    /// this is the semicolon ';'. On OpenVMS systems, this is the
    /// comma ','.

    static std::string current();
    /// Returns the current working directory.

    static std::string home();
    /// Returns the user's home directory.

    static std::string configHome();
    /// Returns the user's config directory.
    ///
    /// On Unix systems, this is the '~/.config/'. On Windows systems,
    /// this is '%APPDATA%'.

    static std::string dataHome();
    /// Returns the user's data directory.
    ///
    /// On Unix systems, this is the '~/.local/share/'. On Windows systems,
    /// this is '%APPDATA%'.

    static std::string tempHome();
    /// Returns the user's temp directory.
    ///
    /// On Unix systems, this is the '~/.local/temp/'.

    static std::string cacheHome();
    /// Returns the user's cache directory.
    ///
    /// On Unix systems, this is the '~/.cache/'. On Windows systems,
    /// this is '%APPDATA%'.

    static std::string temp();
    /// Returns the temporary directory.

    static std::string config();
    /// Returns the systemwide config directory.
    ///
    /// On Unix systems, this is the '/etc/'.

    static std::string null();
    /// Returns the name of the null device.

    static std::string expand(const std::string & path);
    /// Expands all environment variables contained in the path.
    ///
    /// On Unix, a tilde as first character in the path is
    /// replaced with the path to user's home directory.

    static void listRoots(std::vector<std::string> & roots);
    /// Fills the vector with all filesystem roots available on the
    /// system. On Unix, there is exactly one root, "/".
    /// On Windows, the roots are the drive letters.
    /// On OpenVMS, the roots are the mounted disks.

    static bool find(StringVec::const_iterator it, StringVec::const_iterator end, const std::string & name, Path & path);
    /// Searches the file with the given name in the locations (paths) specified
    /// by it and end. A relative path may be given in name.
    ///
    /// If the file is found in one of the locations, the complete
    /// path of the file is stored in the path given as argument and true is returned.
    /// Otherwise false is returned and the path argument remains unchanged.

    static bool find(const std::string & pathList, const std::string & name, Path & path);
    /// Searches the file with the given name in the locations (paths) specified
    /// in pathList. The paths in pathList must be delimited by the platform's
    /// path separator (see pathSeparator()). A relative path may be given in name.
    ///
    /// If the file is found in one of the locations, the complete
    /// path of the file is stored in the path given as argument and true is returned.
    /// Otherwise false is returned and the path argument remains unchanged.

    static std::string transcode(const std::string & path);
    /// On Windows, if POCO has been compiled with Windows UTF-8 support
    /// (POCO_WIN32_UTF8), this function converts a string (usually containing a path)
    /// encoded in UTF-8 into a string encoded in the current Windows code page.
    ///
    /// This function should be used for every string passed as a file name to
    /// a string stream or fopen().
    ///
    /// On all other platforms, or if POCO has not been compiled with Windows UTF-8
    /// support, this function returns the string unchanged.

protected:
    void parseUnix(const std::string & path);
    void parseWindows(const std::string & path);
    void parseVMS(const std::string & path);
    void parseGuess(const std::string & path);
    std::string buildUnix() const;
    std::string buildWindows() const;
    std::string buildVMS() const;

private:
    std::string _node;
    std::string _device;
    std::string _name;
    std::string _version;
    StringVec _dirs;
    bool _absolute;
};


//
// inlines
//
inline bool Path::isAbsolute() const
{
    return _absolute;
}


inline bool Path::isRelative() const
{
    return !_absolute;
}


inline bool Path::isDirectory() const
{
    return _name.empty();
}


inline bool Path::isFile() const
{
    return !_name.empty();
}


inline Path & Path::parse(const std::string & path)
{
    return assign(path);
}


inline Path & Path::parse(const std::string & path, Style style)
{
    return assign(path, style);
}


inline const std::string & Path::getNode() const
{
    return _node;
}


inline const std::string & Path::getDevice() const
{
    return _device;
}


inline const std::string & Path::getFileName() const
{
    return _name;
}


inline int Path::depth() const
{
    return int(_dirs.size());
}


inline const std::string & Path::version() const
{
    return _version;
}


inline Path Path::forDirectory(const std::string & path)
{
    Path p;
    return p.parseDirectory(path);
}


inline Path Path::forDirectory(const std::string & path, Style style)
{
    Path p;
    return p.parseDirectory(path, style);
}


inline char Path::separator()
{
#if defined(POCO_OS_FAMILY_VMS)
    return '.';
#else
    return '/';
#endif
}


inline char Path::pathSeparator()
{
#if defined(POCO_OS_FAMILY_VMS)
    return ',';
#else
    return ':';
#endif
}


inline void swap(Path & p1, Path & p2)
{
    p1.swap(p2);
}


} // namespace Poco


#endif // Foundation_Path_INCLUDED