//===- llvm/System/Path.h - Path Operating System Concept -------*- C++ -*-===// // // The LLVM Compiler Infrastructure // // This file was developed by Reid Spencer and is distributed under the // University of Illinois Open Source License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This file declares the llvm::sys::Path class. // //===----------------------------------------------------------------------===// #ifndef LLVM_SYSTEM_PATH_H #define LLVM_SYSTEM_PATH_H #include "llvm/System/TimeValue.h" #include #include #include namespace llvm { namespace sys { /// This class provides an abstraction for the path to a file or directory /// in the operating system's filesystem and provides various basic operations /// on it. Note that this class only represents the name of a path to a file /// or directory which may or may not be valid for a given machine's file /// system. A Path ensures that the name it encapsulates is syntactical valid /// for the operating system it is running on but does not ensure correctness /// for any particular file system. A Path either references a file or a /// directory and the distinction is consistently maintained. Most operations /// on the class have invariants that require the Path object to be either a /// file path or a directory path, but not both. Those operations will also /// leave the object as either a file path or object path. There is exactly /// one invalid Path which is the empty path. The class should never allow any /// other syntactically invalid non-empty path name to be assigned. Empty /// paths are required in order to indicate an error result. If the path is /// empty, the isValid operation will return false. All operations will fail /// if isValid is false. Operations that change the path will either return /// false if it would cause a syntactically invalid path name (in which case /// the Path object is left unchanged) or throw an std::string exception /// indicating the error. /// @since 1.4 /// @brief An abstraction for operating system paths. class Path { /// @name Types /// @{ public: /// This structure provides basic file system information about a file. It /// is patterned after the stat(2) Unix operating system call but made /// platform independent and eliminates many of the unix-specific fields. /// However, to support llvm-ar, the mode, user, and group fields are /// retained. These pertain to unix security and may not have a meaningful /// value on non-Unix platforms. However, the fileSize and modTime fields /// should always be applicabe on all platforms. The structure is /// filled in by the getStatusInfo method. /// @brief File status structure struct StatusInfo { StatusInfo() : fileSize(0), modTime(0,0), mode(0777), user(999), group(999), isDir(false) { } size_t fileSize; ///< Size of the file in bytes TimeValue modTime; ///< Time of file's modification uint32_t mode; ///< Mode of the file, if applicable uint32_t user; ///< User ID of owner, if applicable uint32_t group; ///< Group ID of owner, if applicable bool isDir; ///< True if this is a directory. }; /// @} /// @name Constructors /// @{ public: /// Construct a path to the root directory of the file system. The root /// directory is a top level directory above which there are no more /// directories. For example, on UNIX, the root directory is /. On Windows /// it is C:\. Other operating systems may have different notions of /// what the root directory is. /// @throws nothing static Path GetRootDirectory(); /// Construct a path to a unique temporary directory that is created in /// a "standard" place for the operating system. The directory is /// guaranteed to be created on exit from this function. If the directory /// cannot be created, the function will throw an exception. /// @throws std::string indicating why the directory could not be created. /// @brief Constrct a path to an new, unique, existing temporary /// directory. static Path GetTemporaryDirectory(); /// Determine the platform-specific location of a library by first /// searching a list of library paths, then searching a list of "well /// known" paths for the platform. T /// @returns a valid Path object if the library was found, an invalid /// one otherwise. /// @throws nothing /// @brief Locate a library in a platform specific manner. static Path GetLibraryPath(const std::string& basename, const std::vector& LibPaths); /// /// Construct a path to the first system library directory. The /// implementation of Path on a given platform must ensure that this /// directory both exists and also contains standard system libraries /// suitable for linking into programs. /// @throws nothing /// @brief Construct a path to the first system library directory static Path GetSystemLibraryPath1(); /// Construct a path to the second system library directory. The /// implementation of Path on a given platform must ensure that this /// directory both exists and also contains standard system libraries /// suitable for linking into programs. Note that the "second" system /// library directory may or may not be different from the first. /// @throws nothing /// @brief Construct a path to the second system library directory static Path GetSystemLibraryPath2(); /// Construct a path to the default LLVM configuration directory. The /// implementation must ensure that this is a well-known (same on many /// systems) directory in which llvm configuration files exist. For /// example, on Unix, the /etc/llvm directory has been selected. /// @throws nothing /// @brief Construct a path to the default LLVM configuration directory static Path GetLLVMDefaultConfigDir(); /// Construct a path to the LLVM installed configuration directory. The /// implementation must ensure that this refers to the "etc" directory of /// the LLVM installation. This is the location where configuration files /// will be located for a particular installation of LLVM on a machine. /// @throws nothing /// @brief Construct a path to the LLVM installed configuration directory static Path GetLLVMConfigDir(); /// Construct a path to the current user's home directory. The /// implementation must use an operating system specific mechanism for /// determining the user's home directory. For example, the environment /// variable "HOME" could be used on Unix. If a given operating system /// does not have the concept of a user's home directory, this static /// constructor must provide the same result as GetRootDirectory. /// @throws nothing /// @brief Construct a path to the current user's "home" directory static Path GetUserHomeDirectory(); /// Return the suffix commonly used on file names that contain a shared /// object, shared archive, or dynamic link library. Such files are /// linked at runtime into a process and their code images are shared /// between processes. /// @returns The dynamic link library suffix for the current platform. /// @brief Return the dynamic link library suffix. static std::string GetDLLSuffix(); /// This is one of the very few ways in which a path can be constructed /// with a syntactically invalid name. The only *legal* invalid name is an /// empty one. Other invalid names are not permitted. Empty paths are /// provided so that they can be used to indicate null or error results in /// other lib/System functionality. /// @throws nothing /// @brief Construct an empty (and invalid) path. Path() : path() {} /// This constructor will accept a std::string as a path but if verifies /// that the path string has a legal syntax for the operating system on /// which it is running. This allows a path to be taken in from outside /// the program. However, if the path is not valid, the Path object will /// be set to an empty string and an exception will be thrown. /// @throws std::string if the path string is not legal. /// @param unverified_path The path to verify and assign. /// @brief Construct a Path from a string. explicit Path(std::string unverified_path); /// @} /// @name Operators /// @{ public: /// Makes a copy of \p that to \p this. /// @returns \p this /// @throws nothing /// @brief Assignment Operator Path & operator = ( const Path & that ) { path = that.path; return *this; } /// Compares \p this Path with \p that Path for equality. /// @returns true if \p this and \p that refer to the same thing. /// @throws nothing /// @brief Equality Operator bool operator == (const Path& that) const { return 0 == path.compare(that.path) ; } /// Compares \p this Path with \p that Path for inequality. /// @returns true if \p this and \p that refer to different things. /// @throws nothing /// @brief Inequality Operator bool operator !=( const Path & that ) const { return 0 != path.compare( that.path ); } /// Determines if \p this Path is less than \p that Path. This is required /// so that Path objects can be placed into ordered collections (e.g. /// std::map). The comparison is done lexicographically as defined by /// the std::string::compare method. /// @returns true if \p this path is lexicographically less than \p that. /// @throws nothing /// @brief Less Than Operator bool operator< (const Path& that) const { return 0 > path.compare( that.path ); } /// @} /// @name Accessors /// @{ public: /// This function will use an operating system specific algorithm to /// determine if the current value of \p this is a syntactically valid /// path name for the operating system. The path name does not need to /// exist, validity is simply syntactical. Empty paths are always invalid. /// @returns true iff the path name is syntactically legal for the /// host operating system. /// @brief Determine if a path is syntactically valid or not. bool isValid() const; /// This function determines if the contents of the path name are /// empty. That is, the path has a zero length. /// @returns true iff the path is empty. /// @brief Determines if the path name is empty (invalid). bool isEmpty() const { return path.empty(); } /// This function determines if the path name in this object is intended /// to reference a legal file name (as opposed to a directory name). This /// function does not verify anything with the file system, it merely /// determines if the syntax of the path represents a file name or not. /// @returns true if this path name references a file. /// @brief Determines if the path name references a file. bool isFile() const; /// This function determines if the path name in this object is intended /// to reference a legal directory name (as opposed to a file name). This /// function does not verify anything with the file system, it merely /// determines if the syntax of the path represents a directory name or /// not. /// @returns true if the path name references a directory /// @brief Determines if the path name references a directory. bool isDirectory() const; /// This function determines if the path name in this object references /// the root (top level directory) of the file system. The details of what /// is considered the "root" may vary from system to system so this method /// will do the necessary checking. /// @returns true iff the path name references the root directory. /// @brief Determines if the path references the root directory. bool isRootDirectory() const; /// This function opens the file associated with the path name provided by /// the Path object and reads its magic number. If the magic number at the /// start of the file matches \p magic, true is returned. In all other /// cases (file not found, file not accessible, etc.) it returns false. /// @returns true if the magic number of the file matches \p magic. /// @brief Determine if file has a specific magic number bool hasMagicNumber(const std::string& magic) const; /// This function retrieves the first \p len bytes of the file associated /// with \p this. These bytes are returned as the "magic number" in the /// \p Magic parameter. /// @returns true if the Path is a file and the magic number is retrieved, /// false otherwise. /// @brief Get the file's magic number. bool getMagicNumber(std::string& Magic, unsigned len) const; /// This function determines if the path name in the object references an /// archive file by looking at its magic number. /// @returns true if the file starts with the magic number for an archive /// file. /// @brief Determine if the path references an archive file. bool isArchive() const; /// This function determines if the path name in the object references an /// LLVM Bytecode file by looking at its magic number. /// @returns true if the file starts with the magic number for LLVM /// bytecode files. /// @brief Determine if the path references a bytecode file. bool isBytecodeFile() const; /// This function determines if the path name references an existing file /// or directory in the file system. Unlike isFile and isDirectory, this /// function actually checks for the existence of the file or directory. /// @returns true if the pathname references an existing file. /// @brief Determines if the path is a file or directory in /// the file system. bool exists() const; /// This function determines if the path name references a readable file /// or directory in the file system. Unlike isFile and isDirectory, this /// function actually checks for the existence and readability (by the /// current program) of the file or directory. /// @returns true if the pathname references a readable file. /// @brief Determines if the path is a readable file or directory /// in the file system. bool readable() const; /// This function determines if the path name references a writable file /// or directory in the file system. Unlike isFile and isDirectory, this /// function actually checks for the existence and writability (by the /// current program) of the file or directory. /// @returns true if the pathname references a writable file. /// @brief Determines if the path is a writable file or directory /// in the file system. bool writable() const; /// This function determines if the path name references an executable /// file in the file system. Unlike isFile and isDirectory, this /// function actually checks for the existence and executability (by /// the current program) of the file. /// @returns true if the pathname references an executable file. /// @brief Determines if the path is an executable file in the file /// system. bool executable() const; /// This function returns the current contents of the path as a /// std::string. This allows the underlying path string to be manipulated /// by other software. /// @returns std::string containing the path name. /// @brief Returns the path as a std::string. std::string get() const { return path; } /// This function returns the last component of the path name. If the /// isDirectory() function would return true then this returns the name /// of the last directory in the path. If the isFile() function would /// return true then this function returns the name of the file without /// any of the preceding directories. /// @returns std::string containing the last component of the path name. /// @brief Returns the last component of the path name. std::string getLast() const; /// This function strips off the path and suffix of the file name and /// returns just the basename. /// @returns std::string containing the basename of the path /// @throws nothing /// @brief Get the base name of the path std::string getBasename() const; /// This function builds a list of paths that are the names of the /// files and directories in a directory. /// @returns false if \p this is not a directory, true otherwise /// @throws std::string if the directory cannot be searched /// @brief Build a list of directory's contents. bool getDirectoryContents(std::set& paths) const; /// Obtain a 'C' string for the path name. /// @returns a 'C' string containing the path name. /// @brief Returns the path as a C string. const char* const c_str() const { return path.c_str(); } /// @} /// @name Mutators /// @{ public: /// The path name is cleared and becomes empty. This is an invalid /// path name but is the *only* invalid path name. This is provided /// so that path objects can be used to indicate the lack of a /// valid path being found. void clear() { path.clear(); } /// This function returns status information about the file. The type of /// path (file or directory) is updated to reflect the actual contents /// of the file system. If the file does not exist, false is returned. /// For other (hard I/O) errors, a std::string is throwing indicating the /// problem. /// @throws std::string if an error occurs. /// @brief Get file status. void getStatusInfo(StatusInfo& info) const; /// This method attempts to set the Path object to \p unverified_path /// and interpret the name as a directory name. The \p unverified_path /// is verified. If verification succeeds then \p unverified_path /// is accepted as a directory and true is returned. Otherwise, /// the Path object remains unchanged and false is returned. /// @returns true if the path was set, false otherwise. /// @param unverified_path The path to be set in Path object. /// @throws nothing /// @brief Set a full path from a std::string bool setDirectory(const std::string& unverified_path); /// This method attempts to set the Path object to \p unverified_path /// and interpret the name as a file name. The \p unverified_path /// is verified. If verification succeeds then \p unverified_path /// is accepted as a file name and true is returned. Otherwise, /// the Path object remains unchanged and false is returned. /// @returns true if the path was set, false otherwise. /// @param unverified_path The path to be set in Path object. /// @throws nothing /// @brief Set a full path from a std::string bool setFile(const std::string& unverified_path); /// The \p dirname is added to the end of the Path if it is a legal /// directory name for the operating system. The precondition for this /// function is that the Path must reference a directory name (i.e. /// isDirectory() returns true). /// @param dirname A string providing the directory name to /// be added to the end of the path. /// @returns false if the directory name could not be added /// @throws nothing /// @brief Adds the name of a directory to a Path. bool appendDirectory( const std::string& dirname ); /// One directory component is removed from the Path name. The Path must /// refer to a non-root directory name (i.e. isDirectory() returns true /// but isRootDirectory() returns false). Upon exit, the Path will /// refer to the directory above it. /// @throws nothing /// @returns false if the directory name could not be removed. /// @brief Removes the last directory component of the Path. bool elideDirectory(); /// The \p filename is added to the end of the Path if it is a legal /// directory name for the operating system. The precondition for this /// function is that the Path reference a directory name (i.e. /// isDirectory() returns true). /// @throws nothing /// @returns false if the file name could not be added. /// @brief Appends the name of a file. bool appendFile( const std::string& filename ); /// One file component is removed from the Path name. The Path must /// refer to a file (i.e. isFile() returns true). Upon exit, /// the Path will refer to the directory above it. /// @throws nothing /// @returns false if the file name could not be removed /// @brief Removes the last file component of the path. bool elideFile(); /// A period and the \p suffix are appended to the end of the pathname. /// The precondition for this function is that the Path reference a file /// name (i.e. isFile() returns true). If the Path is not a file, no /// action is taken and the function returns false. If the path would /// become invalid for the host operating system, false is returned. /// @returns false if the suffix could not be added, true if it was. /// @throws nothing /// @brief Adds a period and the \p suffix to the end of the pathname. bool appendSuffix(const std::string& suffix); /// The suffix of the filename is removed. The suffix begins with and /// includes the last . character in the filename after the last directory /// separator and extends until the end of the name. If no . character is /// after the last directory separator, then the file name is left /// unchanged (i.e. it was already without a suffix) but the function /// returns false. /// @returns false if there was no suffix to remove, true otherwise. /// @throws nothing /// @brief Remove the suffix from a path name. bool elideSuffix(); /// This method attempts to create a directory in the file system with the /// same name as the Path object. The \p create_parents parameter controls /// whether intermediate directories are created or not. if \p /// create_parents is true, then an attempt will be made to create all /// intermediate directories. If \p create_parents is false, then only the /// final directory component of the Path name will be created. The /// created directory will have no entries. /// @returns false if the Path does not reference a directory, true /// otherwise. /// @param create_parents Determines whether non-existent directory /// components other than the last one (the "parents") are created or not. /// @throws std::string if an error occurs. /// @brief Create the directory this Path refers to. bool createDirectory( bool create_parents = false ); /// This method attempts to create a file in the file system with the same /// name as the Path object. The intermediate directories must all exist /// at the time this method is called. Use createDirectories to /// accomplish that. The created file will be empty upon return from this /// function. /// @returns false if the Path does not reference a file, true otherwise. /// @throws std::string if an error occurs. /// @brief Create the file this Path refers to. bool createFile(); /// This is like createFile except that it creates a temporary file. A /// unique temporary file name is generated based on the contents of /// \p this before the call. The new name is assigned to \p this and the /// file is created. Note that this will both change the Path object /// *and* create the corresponding file. This function will ensure that /// the newly generated temporary file name is unique in the file system. /// @throws std::string if there is an error /// @brief Create a unique temporary file bool createTemporaryFile(); /// This method attempts to destroy the directory named by the last in /// the Path name. If \p remove_contents is false, an attempt will be /// made to remove just the directory that this Path object refers to /// (the final Path component). If \p remove_contents is true, an attempt /// will be made to remove the entire contents of the directory, /// recursively. /// @param destroy_contents Indicates whether the contents of a destroyed /// directory should also be destroyed (recursively). /// @returns false if the Path does not refer to a directory, true /// otherwise. /// @throws std::string if there is an error. /// @brief Removes the file or directory from the filesystem. bool destroyDirectory( bool destroy_contents = false ); /// This method attempts to destroy the file named by the last item in the /// Path name. /// @returns false if the Path does not refer to a file, true otherwise. /// @throws std::string if there is an error. /// @brief Destroy the file this Path refers to. bool destroyFile(); /// This method renames the file referenced by \p this as \p newName. Both /// files must exist before making this call. /// @returns false if the Path does not refer to a file, true otherwise. /// @throws std::string if there is an file system error. /// @brief Rename one file as another. bool renameFile(const Path& newName); /// This method sets the access time, modification time, and permission /// mode of the file associated with \p this as given by \p si. /// @returns false if the Path does not refer to a file, true otherwise. /// @throws std::string if the file could not be modified /// @brief Set file times and mode. bool setStatusInfo(const StatusInfo& si ) const ; /// @} /// @name Data /// @{ private: mutable std::string path; ///< Storage for the path name. /// @} }; /// This enumeration delineates the kinds of files that LLVM knows about. enum LLVMFileType { UnknownFileType = 0, ///< Unrecognized file BytecodeFileType = 1, ///< Uncompressed bytecode file CompressedBytecodeFileType = 2, ///< Compressed bytecode file ArchiveFileType = 3, ///< ar style archive file }; /// This utility function allows any memory block to be examined in order /// to determine its file type. LLVMFileType IdentifyFileType(const char*magic, unsigned length); } } // vim: sw=2 #endif