LLVM API Documentation

Path.h

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00001 //===- llvm/System/Path.h - Path Operating System Concept -------*- C++ -*-===//
00002 //
00003 //                     The LLVM Compiler Infrastructure
00004 //
00005 // This file was developed by Reid Spencer and is distributed under the
00006 // University of Illinois Open Source License. See LICENSE.TXT for details.
00007 //
00008 //===----------------------------------------------------------------------===//
00009 //
00010 // This file declares the llvm::sys::Path class.
00011 //
00012 //===----------------------------------------------------------------------===//
00013 
00014 #ifndef LLVM_SYSTEM_PATH_H
00015 #define LLVM_SYSTEM_PATH_H
00016 
00017 #include "llvm/System/TimeValue.h"
00018 #include "llvm/System/IncludeFile.h"
00019 #include <set>
00020 #include <string>
00021 #include <vector>
00022 #include <iosfwd>
00023 
00024 namespace llvm {
00025 namespace sys {
00026 
00027   /// This class provides an abstraction for the path to a file or directory
00028   /// in the operating system's filesystem and provides various basic operations
00029   /// on it.  Note that this class only represents the name of a path to a file
00030   /// or directory which may or may not be valid for a given machine's file
00031   /// system. The class is patterned after the java.io.File class with various
00032   /// extensions and several omissions (not relevant to LLVM).  A Path object
00033   /// ensures that the path it encapsulates is syntactically valid for the
00034   /// operating system it is running on but does not ensure correctness for
00035   /// any particular file system. That is, a syntactically valid path might
00036   /// specify path components that do not exist in the file system and using
00037   /// such a Path to act on the file system could produce errors. There is one
00038   /// invalid Path value which is permitted: the empty path.  The class should
00039   /// never allow a syntactically invalid non-empty path name to be assigned.
00040   /// Empty paths are required in order to indicate an error result in some
00041   /// situations. If the path is empty, the isValid operation will return
00042   /// false. All operations will fail if isValid is false. Operations that
00043   /// change the path will either return false if it would cause a syntactically
00044   /// invalid path name (in which case the Path object is left unchanged) or
00045   /// throw an std::string exception indicating the error. The methods are
00046   /// grouped into four basic categories: Path Accessors (provide information
00047   /// about the path without accessing disk), Disk Accessors (provide
00048   /// information about the underlying file or directory), Path Mutators
00049   /// (change the path information, not the disk), and Disk Mutators (change
00050   /// the disk file/directory referenced by the path). The Disk Mutator methods
00051   /// all have the word "disk" embedded in their method name to reinforce the
00052   /// notion that the operation modifies the file system.
00053   /// @since 1.4
00054   /// @brief An abstraction for operating system paths.
00055   class Path {
00056     /// @name Types
00057     /// @{
00058     public:
00059       /// This structure provides basic file system information about a file. It
00060       /// is patterned after the stat(2) Unix operating system call but made
00061       /// platform independent and eliminates many of the unix-specific fields.
00062       /// However, to support llvm-ar, the mode, user, and group fields are
00063       /// retained. These pertain to unix security and may not have a meaningful
00064       /// value on non-Unix platforms. However, the fileSize and modTime fields
00065       /// should always be applicabe on all platforms.  The structure is
00066       /// filled in by the getStatusInfo method.
00067       /// @brief File status structure
00068       struct StatusInfo {
00069         StatusInfo() : fileSize(0), modTime(0,0), mode(0777), user(999),
00070                        group(999), isDir(false) { }
00071         uint64_t    fileSize;   ///< Size of the file in bytes
00072         TimeValue   modTime;    ///< Time of file's modification
00073         uint32_t    mode;       ///< Mode of the file, if applicable
00074         uint32_t    user;       ///< User ID of owner, if applicable
00075         uint32_t    group;      ///< Group ID of owner, if applicable
00076         bool        isDir;      ///< True if this is a directory.
00077       };
00078 
00079     /// @}
00080     /// @name Constructors
00081     /// @{
00082     public:
00083       /// Construct a path to the root directory of the file system. The root
00084       /// directory is a top level directory above which there are no more
00085       /// directories. For example, on UNIX, the root directory is /. On Windows
00086       /// it is C:\. Other operating systems may have different notions of
00087       /// what the root directory is or none at all. In that case, a consistent
00088       /// default root directory will be used.
00089       static Path GetRootDirectory();
00090 
00091       /// Construct a path to a unique temporary directory that is created in
00092       /// a "standard" place for the operating system. The directory is
00093       /// guaranteed to be created on exit from this function. If the directory
00094       /// cannot be created, the function will throw an exception.
00095       /// @throws std::string indicating why the directory could not be created.
00096       /// @brief Constrct a path to an new, unique, existing temporary
00097       /// directory.
00098       static Path GetTemporaryDirectory();
00099 
00100       /// Construct a vector of sys::Path that contains the "standard" system
00101       /// library paths suitable for linking into programs. This function *must*
00102       /// return the value of LLVM_LIB_SEARCH_PATH as the first item in \p Paths
00103       /// if that environment variable is set and it references a directory.
00104       /// @brief Construct a path to the system library directory
00105       static void GetSystemLibraryPaths(std::vector<sys::Path>& Paths);
00106 
00107       /// Construct a vector of sys::Path that contains the "standard" bytecode
00108       /// library paths suitable for linking into an llvm program. This function
00109       /// *must* return the value of LLVM_LIB_SEARCH_PATH as well as the value
00110       /// of LLVM_LIBDIR. It also must provide the System library paths as
00111       /// returned by GetSystemLibraryPaths.
00112       /// @see GetSystemLibraryPaths
00113       /// @brief Construct a list of directories in which bytecode could be
00114       /// found.
00115       static void GetBytecodeLibraryPaths(std::vector<sys::Path>& Paths);
00116 
00117       /// Find the path to a library using its short name. Use the system
00118       /// dependent library paths to locate the library.
00119       /// @brief Find a library.
00120       static Path  FindLibrary(std::string& short_name);
00121 
00122       /// Construct a path to the default LLVM configuration directory. The
00123       /// implementation must ensure that this is a well-known (same on many
00124       /// systems) directory in which llvm configuration files exist. For
00125       /// example, on Unix, the /etc/llvm directory has been selected.
00126       /// @brief Construct a path to the default LLVM configuration directory
00127       static Path GetLLVMDefaultConfigDir();
00128 
00129       /// Construct a path to the LLVM installed configuration directory. The
00130       /// implementation must ensure that this refers to the "etc" directory of
00131       /// the LLVM installation. This is the location where configuration files
00132       /// will be located for a particular installation of LLVM on a machine.
00133       /// @brief Construct a path to the LLVM installed configuration directory
00134       static Path GetLLVMConfigDir();
00135 
00136       /// Construct a path to the current user's home directory. The
00137       /// implementation must use an operating system specific mechanism for
00138       /// determining the user's home directory. For example, the environment
00139       /// variable "HOME" could be used on Unix. If a given operating system
00140       /// does not have the concept of a user's home directory, this static
00141       /// constructor must provide the same result as GetRootDirectory.
00142       /// @brief Construct a path to the current user's "home" directory
00143       static Path GetUserHomeDirectory();
00144 
00145       /// Return the suffix commonly used on file names that contain a shared
00146       /// object, shared archive, or dynamic link library. Such files are
00147       /// linked at runtime into a process and their code images are shared
00148       /// between processes.
00149       /// @returns The dynamic link library suffix for the current platform.
00150       /// @brief Return the dynamic link library suffix.
00151       static std::string GetDLLSuffix();
00152 
00153       /// This is one of the very few ways in which a path can be constructed
00154       /// with a syntactically invalid name. The only *legal* invalid name is an
00155       /// empty one. Other invalid names are not permitted. Empty paths are
00156       /// provided so that they can be used to indicate null or error results in
00157       /// other lib/System functionality.
00158       /// @brief Construct an empty (and invalid) path.
00159       Path() : path() {}
00160 
00161       /// This constructor will accept a std::string as a path but it verifies
00162       /// that the path string has a legal syntax for the operating system on
00163       /// which it is running. This allows a path to be taken in from outside
00164       /// the program. However, if the path is not valid, the Path object will
00165       /// be set to an empty string and an exception will be thrown.
00166       /// @throws std::string if \p unverified_path is not legal.
00167       /// @param unverified_path The path to verify and assign.
00168       /// @brief Construct a Path from a string.
00169       explicit Path(const std::string& unverified_path);
00170 
00171     /// @}
00172     /// @name Operators
00173     /// @{
00174     public:
00175       /// Makes a copy of \p that to \p this.
00176       /// @returns \p this
00177       /// @brief Assignment Operator
00178       Path & operator = ( const Path & that ) {
00179         path = that.path;
00180         return *this;
00181       }
00182 
00183       /// Compares \p this Path with \p that Path for equality.
00184       /// @returns true if \p this and \p that refer to the same thing.
00185       /// @brief Equality Operator
00186       bool operator == (const Path& that) const {
00187         return 0 == path.compare(that.path) ;
00188       }
00189 
00190       /// Compares \p this Path with \p that Path for inequality.
00191       /// @returns true if \p this and \p that refer to different things.
00192       /// @brief Inequality Operator
00193       bool operator !=( const Path & that ) const {
00194         return 0 != path.compare( that.path );
00195       }
00196 
00197       /// Determines if \p this Path is less than \p that Path. This is required
00198       /// so that Path objects can be placed into ordered collections (e.g.
00199       /// std::map). The comparison is done lexicographically as defined by
00200       /// the std::string::compare method.
00201       /// @returns true if \p this path is lexicographically less than \p that.
00202       /// @brief Less Than Operator
00203       bool operator< (const Path& that) const {
00204         return 0 > path.compare( that.path );
00205       }
00206 
00207     /// @}
00208     /// @name Path Accessors
00209     /// @{
00210     public:
00211       /// This function will use an operating system specific algorithm to
00212       /// determine if the current value of \p this is a syntactically valid
00213       /// path name for the operating system. The path name does not need to
00214       /// exist, validity is simply syntactical. Empty paths are always invalid.
00215       /// @returns true iff the path name is syntactically legal for the
00216       /// host operating system.
00217       /// @brief Determine if a path is syntactically valid or not.
00218       bool isValid() const;
00219 
00220       /// This function determines if the contents of the path name are
00221       /// empty. That is, the path has a zero length. This does NOT determine if
00222       /// if the file is empty. Use the getSize method for that.
00223       /// @returns true iff the path is empty.
00224       /// @brief Determines if the path name is empty (invalid).
00225       bool isEmpty() const { return path.empty(); }
00226 
00227       /// This function returns the current contents of the path as a
00228       /// std::string. This allows the underlying path string to be manipulated.
00229       /// @returns std::string containing the path name.
00230       /// @brief Returns the path as a std::string.
00231       const std::string& toString() const { return path; }
00232 
00233       /// This function returns the last component of the path name. The last
00234       /// component is the file or directory name occuring after the last
00235       /// directory separator. If no directory separator is present, the entire
00236       /// path name is returned (i.e. same as toString).
00237       /// @returns std::string containing the last component of the path name.
00238       /// @brief Returns the last component of the path name.
00239       std::string getLast() const;
00240 
00241       /// This function strips off the path and suffix of the file or directory
00242       /// name and returns just the basename. For example /a/foo.bar would cause
00243       /// this function to return "foo".
00244       /// @returns std::string containing the basename of the path
00245       /// @brief Get the base name of the path
00246       std::string getBasename() const;
00247 
00248       /// Obtain a 'C' string for the path name.
00249       /// @returns a 'C' string containing the path name.
00250       /// @brief Returns the path as a C string.
00251       const char* const c_str() const { return path.c_str(); }
00252 
00253     /// @}
00254     /// @name Disk Accessors
00255     /// @{
00256     public:
00257       /// This function determines if the object referenced by this path is
00258       /// a file or not. This function accesses the underlying file system to
00259       /// determine the type of entity referenced by the path.
00260       /// @returns true if this path name references a file.
00261       /// @brief Determines if the path name references a file.
00262       bool isFile() const;
00263 
00264       /// This function determines if the object referenced by this path is a
00265       /// directory or not. This function accesses the underlying file system to
00266       /// determine the type of entity referenced by the path.
00267       /// @returns true if the path name references a directory
00268       /// @brief Determines if the path name references a directory.
00269       bool isDirectory() const;
00270 
00271       /// This function determines if the path refers to a hidden file. The
00272       /// notion of hidden files is defined by  the underlying system. The
00273       /// system may not support hidden files in which case this function always
00274       /// returns false on such systems. Hidden files have the "hidden"
00275       /// attribute set on Win32. On Unix, hidden files start with a period.
00276       /// @brief Determines if the path name references a hidden file.
00277       bool isHidden() const;
00278 
00279       /// This function determines if the path name in this object references
00280       /// the root (top level directory) of the file system. The details of what
00281       /// is considered the "root" may vary from system to system so this method
00282       /// will do the necessary checking.
00283       /// @returns true iff the path name references the root directory.
00284       /// @brief Determines if the path references the root directory.
00285       bool isRootDirectory() const;
00286 
00287       /// This function opens the file associated with the path name provided by
00288       /// the Path object and reads its magic number. If the magic number at the
00289       /// start of the file matches \p magic, true is returned. In all other
00290       /// cases (file not found, file not accessible, etc.) it returns false.
00291       /// @returns true if the magic number of the file matches \p magic.
00292       /// @brief Determine if file has a specific magic number
00293       bool hasMagicNumber(const std::string& magic) const;
00294 
00295       /// This function retrieves the first \p len bytes of the file associated
00296       /// with \p this. These bytes are returned as the "magic number" in the
00297       /// \p Magic parameter.
00298       /// @returns true if the Path is a file and the magic number is retrieved,
00299       /// false otherwise.
00300       /// @brief Get the file's magic number.
00301       bool getMagicNumber(std::string& Magic, unsigned len) const;
00302 
00303       /// This function determines if the path name in the object references an
00304       /// archive file by looking at its magic number.
00305       /// @returns true if the file starts with the magic number for an archive
00306       /// file.
00307       /// @brief Determine if the path references an archive file.
00308       bool isArchive() const;
00309 
00310       /// This function determines if the path name in the object references an
00311       /// LLVM Bytecode file by looking at its magic number.
00312       /// @returns true if the file starts with the magic number for LLVM
00313       /// bytecode files.
00314       /// @brief Determine if the path references a bytecode file.
00315       bool isBytecodeFile() const;
00316 
00317       /// This function determines if the path name in the object references a
00318       /// native Dynamic Library (shared library, shared object) by looking at
00319       /// the file's magic number. The Path object must reference a file, not a
00320       /// directory.
00321       /// @return strue if the file starts with the magid number for a native
00322       /// shared library.
00323       /// @brief Determine if the path reference a dynamic library.
00324       bool isDynamicLibrary() const;
00325 
00326       /// This function determines if the path name references an existing file
00327       /// or directory in the file system.
00328       /// @returns true if the pathname references an existing file or
00329       /// directory.
00330       /// @brief Determines if the path is a file or directory in
00331       /// the file system.
00332       bool exists() const;
00333 
00334       /// This function determines if the path name references a readable file
00335       /// or directory in the file system. This function checks for
00336       /// the existence and readability (by the current program) of the file
00337       /// or directory.
00338       /// @returns true if the pathname references a readable file.
00339       /// @brief Determines if the path is a readable file or directory
00340       /// in the file system.
00341       bool canRead() const;
00342 
00343       /// This function determines if the path name references a writable file
00344       /// or directory in the file system. This function checks for the
00345       /// existence and writability (by the current program) of the file or
00346       /// directory.
00347       /// @returns true if the pathname references a writable file.
00348       /// @brief Determines if the path is a writable file or directory
00349       /// in the file system.
00350       bool canWrite() const;
00351 
00352       /// This function determines if the path name references an executable
00353       /// file in the file system. This function checks for the existence and
00354       /// executability (by the current program) of the file.
00355       /// @returns true if the pathname references an executable file.
00356       /// @brief Determines if the path is an executable file in the file
00357       /// system.
00358       bool canExecute() const;
00359 
00360       /// This function builds a list of paths that are the names of the
00361       /// files and directories in a directory.
00362       /// @returns false if \p this is not a directory, true otherwise
00363       /// @throws std::string if the directory cannot be searched
00364       /// @brief Build a list of directory's contents.
00365       bool getDirectoryContents(std::set<Path>& paths) const;
00366 
00367       /// This function returns status information about the file. The type of
00368       /// path (file or directory) is updated to reflect the actual contents
00369       /// of the file system. If the file does not exist, false is returned.
00370       /// For other (hard I/O) errors, a std::string is thrown indicating the
00371       /// problem.
00372       /// @throws std::string if an error occurs.
00373       /// @brief Get file status.
00374       void getStatusInfo(StatusInfo& info) const;
00375 
00376       /// This function returns the last modified time stamp for the file
00377       /// referenced by this path. The Path may reference a file or a directory.
00378       /// If the file does not exist, a ZeroTime timestamp is returned.
00379       /// @returns last modified timestamp of the file/directory or ZeroTime
00380       /// @brief Get file timestamp.
00381       inline TimeValue getTimestamp() const {
00382         StatusInfo info; getStatusInfo(info); return info.modTime;
00383       }
00384 
00385       /// This function returns the size of the file referenced by this path.
00386       /// @brief Get file size.
00387       inline size_t getSize() const {
00388         StatusInfo info; getStatusInfo(info); return info.fileSize;
00389       }
00390 
00391     /// @}
00392     /// @name Path Mutators
00393     /// @{
00394     public:
00395       /// The path name is cleared and becomes empty. This is an invalid
00396       /// path name but is the *only* invalid path name. This is provided
00397       /// so that path objects can be used to indicate the lack of a
00398       /// valid path being found.
00399       /// @brief Make the path empty.
00400       void clear() { path.clear(); }
00401 
00402       /// This method sets the Path object to \p unverified_path. This can fail
00403       /// if the \p unverified_path does not pass the syntactic checks of the
00404       /// isValid() method. If verification fails, the Path object remains
00405       /// unchanged and false is returned. Otherwise true is returned and the
00406       /// Path object takes on the path value of \p unverified_path
00407       /// @returns true if the path was set, false otherwise.
00408       /// @param unverified_path The path to be set in Path object.
00409       /// @brief Set a full path from a std::string
00410       bool set(const std::string& unverified_path);
00411 
00412       /// One path component is removed from the Path. If only one component is
00413       /// present in the path, the Path object becomes empty. If the Path object
00414       /// is empty, no change is made.
00415       /// @returns false if the path component could not be removed.
00416       /// @brief Removes the last directory component of the Path.
00417       bool eraseComponent();
00418 
00419       /// The \p component is added to the end of the Path if it is a legal
00420       /// name for the operating system. A directory separator will be added if
00421       /// needed.
00422       /// @returns false if the path component could not be added.
00423       /// @brief Appends one path component to the Path.
00424       bool appendComponent( const std::string& component );
00425 
00426       /// A period and the \p suffix are appended to the end of the pathname.
00427       /// The precondition for this function is that the Path reference a file
00428       /// name (i.e. isFile() returns true). If the Path is not a file, no
00429       /// action is taken and the function returns false. If the path would
00430       /// become invalid for the host operating system, false is returned.
00431       /// @returns false if the suffix could not be added, true if it was.
00432       /// @brief Adds a period and the \p suffix to the end of the pathname.
00433       bool appendSuffix(const std::string& suffix);
00434 
00435       /// The suffix of the filename is erased. The suffix begins with and
00436       /// includes the last . character in the filename after the last directory
00437       /// separator and extends until the end of the name. If no . character is
00438       /// after the last directory separator, then the file name is left
00439       /// unchanged (i.e. it was already without a suffix) but the function
00440       /// returns false.
00441       /// @returns false if there was no suffix to remove, true otherwise.
00442       /// @brief Remove the suffix from a path name.
00443       bool eraseSuffix();
00444 
00445       /// The current Path name is made unique in the file system. Upon return,
00446       /// the Path will have been changed to make a unique file in the file
00447       /// system or it will not have been changed if the current path name is
00448       /// already unique.
00449       /// @throws std::string if an unrecoverable error occurs.
00450       /// @brief Make the current path name unique in the file system.
00451       void makeUnique( bool reuse_current = true );
00452 
00453     /// @}
00454     /// @name Disk Mutators
00455     /// @{
00456     public:
00457       /// This method attempts to make the file referenced by the Path object
00458       /// available for reading so that the canRead() method will return true.
00459       /// @brief Make the file readable;
00460       void makeReadableOnDisk();
00461 
00462       /// This method attempts to make the file referenced by the Path object
00463       /// available for writing so that the canWrite() method will return true.
00464       /// @brief Make the file writable;
00465       void makeWriteableOnDisk();
00466 
00467       /// This method attempts to make the file referenced by the Path object
00468       /// available for execution so that the canExecute() method will return
00469       /// true.
00470       /// @brief Make the file readable;
00471       void makeExecutableOnDisk();
00472 
00473       /// This method allows the last modified time stamp and permission bits
00474       /// to be set on the disk object referenced by the Path.
00475       /// @throws std::string if an error occurs.
00476       /// @returns true
00477       /// @brief Set the status information.
00478       bool setStatusInfoOnDisk(const StatusInfo& si) const;
00479 
00480       /// This method attempts to create a directory in the file system with the
00481       /// same name as the Path object. The \p create_parents parameter controls
00482       /// whether intermediate directories are created or not. if \p
00483       /// create_parents is true, then an attempt will be made to create all
00484       /// intermediate directories, as needed. If \p create_parents is false,
00485       /// then only the final directory component of the Path name will be
00486       /// created. The created directory will have no entries.
00487       /// @returns false if the Path does not reference a directory, true
00488       /// otherwise.
00489       /// @param create_parents Determines whether non-existent directory
00490       /// components other than the last one (the "parents") are created or not.
00491       /// @throws std::string if an error occurs.
00492       /// @brief Create the directory this Path refers to.
00493       bool createDirectoryOnDisk( bool create_parents = false );
00494 
00495       /// This method attempts to create a file in the file system with the same
00496       /// name as the Path object. The intermediate directories must all exist
00497       /// at the time this method is called. Use createDirectoriesOnDisk to
00498       /// accomplish that. The created file will be empty upon return from this
00499       /// function.
00500       /// @returns false if the Path does not reference a file, true otherwise.
00501       /// @throws std::string if an error occurs.
00502       /// @brief Create the file this Path refers to.
00503       bool createFileOnDisk();
00504 
00505       /// This is like createFile except that it creates a temporary file. A
00506       /// unique temporary file name is generated based on the contents of
00507       /// \p this before the call. The new name is assigned to \p this and the
00508       /// file is created.  Note that this will both change the Path object
00509       /// *and* create the corresponding file. This function will ensure that
00510       /// the newly generated temporary file name is unique in the file system.
00511       /// @param reuse_current When set to true, this parameter indicates that
00512       /// if the current file name does not exist then it will be used without
00513       /// modification.
00514       /// @returns true if successful, false if the file couldn't be created.
00515       /// @throws std::string if there is a hard error creating the temp file
00516       /// name.
00517       /// @brief Create a unique temporary file
00518       bool createTemporaryFileOnDisk(bool reuse_current = false);
00519 
00520       /// This method renames the file referenced by \p this as \p newName. The
00521       /// file referenced by \p this must exist. The file referenced by
00522       /// \p newName does not need to exist.
00523       /// @returns true
00524       /// @throws std::string if there is an file system error.
00525       /// @brief Rename one file as another.
00526       bool renamePathOnDisk(const Path& newName);
00527 
00528       /// This method attempts to destroy the file or directory named by the
00529       /// last component of the Path. If the Path refers to a directory and the
00530       /// \p destroy_contents is false, an attempt will be made to remove just
00531       /// the directory (the final Path component). If \p destroy_contents is
00532       /// true, an attempt will be made to remove the entire contents of the
00533       /// directory, recursively. If the Path refers to a file, the
00534       /// \p destroy_contents parameter is ignored.
00535       /// @param destroy_contents Indicates whether the contents of a destroyed
00536       /// directory should also be destroyed (recursively).
00537       /// @returns true if the file/directory was destroyed, false if the path
00538       /// refers to something that is neither a file nor a directory.
00539       /// @throws std::string if there is an error.
00540       /// @brief Removes the file or directory from the filesystem.
00541       bool eraseFromDisk( bool destroy_contents = false ) const;
00542 
00543     /// @}
00544     /// @name Data
00545     /// @{
00546     private:
00547         mutable std::string path;   ///< Storage for the path name.
00548 
00549     /// @}
00550   };
00551 
00552   /// This enumeration delineates the kinds of files that LLVM knows about.
00553   enum LLVMFileType {
00554     UnknownFileType = 0,            ///< Unrecognized file
00555     BytecodeFileType = 1,           ///< Uncompressed bytecode file
00556     CompressedBytecodeFileType = 2, ///< Compressed bytecode file
00557     ArchiveFileType = 3             ///< ar style archive file
00558   };
00559 
00560   /// This utility function allows any memory block to be examined in order
00561   /// to determine its file type.
00562   LLVMFileType IdentifyFileType(const char*magic, unsigned length);
00563 
00564   /// This function can be used to copy the file specified by Src to the
00565   /// file specified by Dest. If an error occurs, Dest is removed.
00566   /// @throws std::string if an error opening or writing the files occurs.
00567   /// @brief Copy one file to another.
00568   void CopyFile(const Path& Dest, const Path& Src);
00569 }
00570 
00571 std::ostream& operator<<(std::ostream& strm, const sys::Path& aPath);
00572 
00573 }
00574 
00575 FORCE_DEFINING_FILE_TO_BE_LINKED(SystemPath)
00576 #endif