//===- llvm/Support/Path.h - Path Operating System Concept ------*- C++ -*-===// // // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. // See https://llvm.org/LICENSE.txt for license information. // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception // //===----------------------------------------------------------------------===// // // This file declares the llvm::sys::path namespace. It is designed after // TR2/boost filesystem (v3), but modified to remove exception handling and the // path class. // //===----------------------------------------------------------------------===// #ifndef LLVM_SUPPORT_PATH_H #define LLVM_SUPPORT_PATH_H #include "llvm/ADT/Twine.h" #include "llvm/ADT/iterator.h" #include "llvm/Support/DataTypes.h" #include <iterator> namespace llvm { namespace sys { namespace path { enum class Style { … }; /// Check if \p S uses POSIX path rules. constexpr bool is_style_posix(Style S) { … } /// Check if \p S uses Windows path rules. constexpr bool is_style_windows(Style S) { … } /// @name Lexical Component Iterator /// @{ /// Path iterator. /// /// This is an input iterator that iterates over the individual components in /// \a path. The traversal order is as follows: /// * The root-name element, if present. /// * The root-directory element, if present. /// * Each successive filename element, if present. /// * Dot, if one or more trailing non-root slash characters are present. /// Traversing backwards is possible with \a reverse_iterator /// /// Iteration examples. Each component is separated by ',': /// @code /// / => / /// /foo => /,foo /// foo/ => foo,. /// /foo/bar => /,foo,bar /// ../ => ..,. /// C:\foo\bar => C:,\,foo,bar /// @endcode class const_iterator : public iterator_facade_base<const_iterator, std::input_iterator_tag, const StringRef> { … }; /// Reverse path iterator. /// /// This is an input iterator that iterates over the individual components in /// \a path in reverse order. The traversal order is exactly reversed from that /// of \a const_iterator class reverse_iterator : public iterator_facade_base<reverse_iterator, std::input_iterator_tag, const StringRef> { … }; /// Get begin iterator over \a path. /// @param path Input path. /// @returns Iterator initialized with the first component of \a path. const_iterator begin(StringRef path, Style style = Style::native); /// Get end iterator over \a path. /// @param path Input path. /// @returns Iterator initialized to the end of \a path. const_iterator end(StringRef path); /// Get reverse begin iterator over \a path. /// @param path Input path. /// @returns Iterator initialized with the first reverse component of \a path. reverse_iterator rbegin(StringRef path, Style style = Style::native); /// Get reverse end iterator over \a path. /// @param path Input path. /// @returns Iterator initialized to the reverse end of \a path. reverse_iterator rend(StringRef path); /// @} /// @name Lexical Modifiers /// @{ /// Remove the last component from \a path unless it is the root dir. /// /// Similar to the POSIX "dirname" utility. /// /// @code /// directory/filename.cpp => directory/ /// directory/ => directory /// filename.cpp => <empty> /// / => / /// @endcode /// /// @param path A path that is modified to not have a file component. void remove_filename(SmallVectorImpl<char> &path, Style style = Style::native); /// Replace the file extension of \a path with \a extension. /// /// @code /// ./filename.cpp => ./filename.extension /// ./filename => ./filename.extension /// ./ => ./.extension /// @endcode /// /// @param path A path that has its extension replaced with \a extension. /// @param extension The extension to be added. It may be empty. It may also /// optionally start with a '.', if it does not, one will be /// prepended. void replace_extension(SmallVectorImpl<char> &path, const Twine &extension, Style style = Style::native); /// Replace matching path prefix with another path. /// /// @code /// /foo, /old, /new => /foo /// /old, /old, /new => /new /// /old, /old/, /new => /old /// /old/foo, /old, /new => /new/foo /// /old/foo, /old/, /new => /new/foo /// /old/foo, /old/, /new/ => /new/foo /// /oldfoo, /old, /new => /oldfoo /// /foo, <empty>, /new => /new/foo /// /foo, <empty>, new => new/foo /// /old/foo, /old, <empty> => /foo /// @endcode /// /// @param Path If \a Path starts with \a OldPrefix modify to instead /// start with \a NewPrefix. /// @param OldPrefix The path prefix to strip from \a Path. /// @param NewPrefix The path prefix to replace \a NewPrefix with. /// @param style The style used to match the prefix. Exact match using /// Posix style, case/separator insensitive match for Windows style. /// @result true if \a Path begins with OldPrefix bool replace_path_prefix(SmallVectorImpl<char> &Path, StringRef OldPrefix, StringRef NewPrefix, Style style = Style::native); /// Remove redundant leading "./" pieces and consecutive separators. /// /// @param path Input path. /// @result The cleaned-up \a path. StringRef remove_leading_dotslash(StringRef path, Style style = Style::native); /// In-place remove any './' and optionally '../' components from a path. /// /// @param path processed path /// @param remove_dot_dot specify if '../' (except for leading "../") should be /// removed /// @result True if path was changed bool remove_dots(SmallVectorImpl<char> &path, bool remove_dot_dot = false, Style style = Style::native); /// Append to path. /// /// @code /// /foo + bar/f => /foo/bar/f /// /foo/ + bar/f => /foo/bar/f /// foo + bar/f => foo/bar/f /// @endcode /// /// @param path Set to \a path + \a component. /// @param a The component to be appended to \a path. void append(SmallVectorImpl<char> &path, const Twine &a, const Twine &b = "", const Twine &c = "", const Twine &d = ""); void append(SmallVectorImpl<char> &path, Style style, const Twine &a, const Twine &b = "", const Twine &c = "", const Twine &d = ""); /// Append to path. /// /// @code /// /foo + [bar,f] => /foo/bar/f /// /foo/ + [bar,f] => /foo/bar/f /// foo + [bar,f] => foo/bar/f /// @endcode /// /// @param path Set to \a path + [\a begin, \a end). /// @param begin Start of components to append. /// @param end One past the end of components to append. void append(SmallVectorImpl<char> &path, const_iterator begin, const_iterator end, Style style = Style::native); /// @} /// @name Transforms (or some other better name) /// @{ /// Convert path to the native form. This is used to give paths to users and /// operating system calls in the platform's normal way. For example, on Windows /// all '/' are converted to '\'. On Unix, it converts all '\' to '/'. /// /// @param path A path that is transformed to native format. /// @param result Holds the result of the transformation. void native(const Twine &path, SmallVectorImpl<char> &result, Style style = Style::native); /// Convert path to the native form in place. This is used to give paths to /// users and operating system calls in the platform's normal way. For example, /// on Windows all '/' are converted to '\'. /// /// @param path A path that is transformed to native format. void native(SmallVectorImpl<char> &path, Style style = Style::native); /// For Windows path styles, convert path to use the preferred path separators. /// For other styles, do nothing. /// /// @param path A path that is transformed to preferred format. inline void make_preferred(SmallVectorImpl<char> &path, Style style = Style::native) { … } /// Replaces backslashes with slashes if Windows. /// /// @param path processed path /// @result The result of replacing backslashes with forward slashes if Windows. /// On Unix, this function is a no-op because backslashes are valid path /// chracters. std::string convert_to_slash(StringRef path, Style style = Style::native); /// @} /// @name Lexical Observers /// @{ /// Get root name. /// /// @code /// //net/hello => //net /// c:/hello => c: (on Windows, on other platforms nothing) /// /hello => <empty> /// @endcode /// /// @param path Input path. /// @result The root name of \a path if it has one, otherwise "". StringRef root_name(StringRef path, Style style = Style::native); /// Get root directory. /// /// @code /// /goo/hello => / /// c:/hello => / /// d/file.txt => <empty> /// @endcode /// /// @param path Input path. /// @result The root directory of \a path if it has one, otherwise /// "". StringRef root_directory(StringRef path, Style style = Style::native); /// Get root path. /// /// Equivalent to root_name + root_directory. /// /// @param path Input path. /// @result The root path of \a path if it has one, otherwise "". StringRef root_path(StringRef path, Style style = Style::native); /// Get relative path. /// /// @code /// C:\hello\world => hello\world /// foo/bar => foo/bar /// /foo/bar => foo/bar /// @endcode /// /// @param path Input path. /// @result The path starting after root_path if one exists, otherwise "". StringRef relative_path(StringRef path, Style style = Style::native); /// Get parent path. /// /// @code /// / => <empty> /// /foo => / /// foo/../bar => foo/.. /// @endcode /// /// @param path Input path. /// @result The parent path of \a path if one exists, otherwise "". StringRef parent_path(StringRef path, Style style = Style::native); /// Get filename. /// /// @code /// /foo.txt => foo.txt /// . => . /// .. => .. /// / => / /// @endcode /// /// @param path Input path. /// @result The filename part of \a path. This is defined as the last component /// of \a path. Similar to the POSIX "basename" utility. StringRef filename(StringRef path, Style style = Style::native); /// Get stem. /// /// If filename contains a dot but not solely one or two dots, result is the /// substring of filename ending at (but not including) the last dot. Otherwise /// it is filename. /// /// @code /// /foo/bar.txt => bar /// /foo/bar => bar /// /foo/.txt => <empty> /// /foo/. => . /// /foo/.. => .. /// @endcode /// /// @param path Input path. /// @result The stem of \a path. StringRef stem(StringRef path, Style style = Style::native); /// Get extension. /// /// If filename contains a dot but not solely one or two dots, result is the /// substring of filename starting at (and including) the last dot, and ending /// at the end of \a path. Otherwise "". /// /// @code /// /foo/bar.txt => .txt /// /foo/bar => <empty> /// /foo/.txt => .txt /// @endcode /// /// @param path Input path. /// @result The extension of \a path. StringRef extension(StringRef path, Style style = Style::native); /// Check whether the given char is a path separator on the host OS. /// /// @param value a character /// @result true if \a value is a path separator character on the host OS bool is_separator(char value, Style style = Style::native); /// Return the preferred separator for this platform. /// /// @result StringRef of the preferred separator, null-terminated. StringRef get_separator(Style style = Style::native); /// Get the typical temporary directory for the system, e.g., /// "/var/tmp" or "C:/TEMP" /// /// @param erasedOnReboot Whether to favor a path that is erased on reboot /// rather than one that potentially persists longer. This parameter will be /// ignored if the user or system has set the typical environment variable /// (e.g., TEMP on Windows, TMPDIR on *nix) to specify a temporary directory. /// /// @param result Holds the resulting path name. void system_temp_directory(bool erasedOnReboot, SmallVectorImpl<char> &result); /// Get the user's home directory. /// /// @param result Holds the resulting path name. /// @result True if a home directory is set, false otherwise. bool home_directory(SmallVectorImpl<char> &result); /// Get the directory where packages should read user-specific configurations. /// e.g. $XDG_CONFIG_HOME. /// /// @param result Holds the resulting path name. /// @result True if the appropriate path was determined, it need not exist. bool user_config_directory(SmallVectorImpl<char> &result); /// Get the directory where installed packages should put their /// machine-local cache, e.g. $XDG_CACHE_HOME. /// /// @param result Holds the resulting path name. /// @result True if the appropriate path was determined, it need not exist. bool cache_directory(SmallVectorImpl<char> &result); /// Has root name? /// /// root_name != "" /// /// @param path Input path. /// @result True if the path has a root name, false otherwise. bool has_root_name(const Twine &path, Style style = Style::native); /// Has root directory? /// /// root_directory != "" /// /// @param path Input path. /// @result True if the path has a root directory, false otherwise. bool has_root_directory(const Twine &path, Style style = Style::native); /// Has root path? /// /// root_path != "" /// /// @param path Input path. /// @result True if the path has a root path, false otherwise. bool has_root_path(const Twine &path, Style style = Style::native); /// Has relative path? /// /// relative_path != "" /// /// @param path Input path. /// @result True if the path has a relative path, false otherwise. bool has_relative_path(const Twine &path, Style style = Style::native); /// Has parent path? /// /// parent_path != "" /// /// @param path Input path. /// @result True if the path has a parent path, false otherwise. bool has_parent_path(const Twine &path, Style style = Style::native); /// Has filename? /// /// filename != "" /// /// @param path Input path. /// @result True if the path has a filename, false otherwise. bool has_filename(const Twine &path, Style style = Style::native); /// Has stem? /// /// stem != "" /// /// @param path Input path. /// @result True if the path has a stem, false otherwise. bool has_stem(const Twine &path, Style style = Style::native); /// Has extension? /// /// extension != "" /// /// @param path Input path. /// @result True if the path has a extension, false otherwise. bool has_extension(const Twine &path, Style style = Style::native); /// Is path absolute? /// /// According to cppreference.com, C++17 states: "An absolute path is a path /// that unambiguously identifies the location of a file without reference to /// an additional starting location." /// /// In other words, the rules are: /// 1) POSIX style paths with nonempty root directory are absolute. /// 2) Windows style paths with nonempty root name and root directory are /// absolute. /// 3) No other paths are absolute. /// /// \see has_root_name /// \see has_root_directory /// /// @param path Input path. /// @result True if the path is absolute, false if it is not. bool is_absolute(const Twine &path, Style style = Style::native); /// Is path absolute using GNU rules? /// /// GNU rules are: /// 1) Paths starting with a path separator are absolute. /// 2) Windows style paths are also absolute if they start with a character /// followed by ':'. /// 3) No other paths are absolute. /// /// On Windows style the path "C:\Users\Default" has "C:" as root name and "\" /// as root directory. /// /// Hence "C:" on Windows is absolute under GNU rules and not absolute under /// C++17 because it has no root directory. Likewise "/" and "\" on Windows are /// absolute under GNU and are not absolute under C++17 due to empty root name. /// /// \see has_root_name /// \see has_root_directory /// /// @param path Input path. /// @param style The style of \p path (e.g. Windows or POSIX). "native" style /// means to derive the style from the host. /// @result True if the path is absolute following GNU rules, false if it is /// not. bool is_absolute_gnu(const Twine &path, Style style = Style::native); /// Is path relative? /// /// @param path Input path. /// @result True if the path is relative, false if it is not. bool is_relative(const Twine &path, Style style = Style::native); } // end namespace path } // end namespace sys } // end namespace llvm #endif