| //===- 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> |
| #include <system_error> |
| |
| namespace llvm { |
| namespace sys { |
| namespace path { |
| |
| enum class Style { |
| native, |
| posix, |
| windows_slash, |
| windows_backslash, |
| windows = windows_backslash, // deprecated |
| }; |
| |
| /// Check if \p S uses POSIX path rules. |
| constexpr bool is_style_posix(Style S) { |
| if (S == Style::posix) |
| return true; |
| if (S != Style::native) |
| return false; |
| #if defined(_WIN32) |
| return false; |
| #else |
| return true; |
| #endif |
| } |
| |
| /// Check if \p S uses Windows path rules. |
| constexpr bool is_style_windows(Style S) { return !is_style_posix(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> { |
| StringRef Path; ///< The entire path. |
| StringRef Component; ///< The current component. Not necessarily in Path. |
| size_t Position = 0; ///< The iterators current position within Path. |
| Style S = Style::native; ///< The path style to use. |
| |
| // An end iterator has Position = Path.size() + 1. |
| friend const_iterator begin(StringRef path, Style style); |
| friend const_iterator end(StringRef path); |
| |
| public: |
| reference operator*() const { return Component; } |
| const_iterator &operator++(); // preincrement |
| bool operator==(const const_iterator &RHS) const; |
| |
| /// Difference in bytes between this and RHS. |
| ptrdiff_t operator-(const const_iterator &RHS) const; |
| }; |
| |
| /// 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> { |
| StringRef Path; ///< The entire path. |
| StringRef Component; ///< The current component. Not necessarily in Path. |
| size_t Position = 0; ///< The iterators current position within Path. |
| Style S = Style::native; ///< The path style to use. |
| |
| friend reverse_iterator rbegin(StringRef path, Style style); |
| friend reverse_iterator rend(StringRef path); |
| |
| public: |
| reference operator*() const { return Component; } |
| reverse_iterator &operator++(); // preincrement |
| bool operator==(const reverse_iterator &RHS) const; |
| |
| /// Difference in bytes between this and RHS. |
| ptrdiff_t operator-(const reverse_iterator &RHS) const; |
| }; |
| |
| /// 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) { |
| if (!is_style_windows(style)) |
| return; |
| native(path, style); |
| } |
| |
| /// 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 |