1 //===- llvm/System/Path.h - Path Operating System Concept -------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by Reid Spencer and is distributed under the
6 // University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file declares the llvm::sys::Path class.
12 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_SYSTEM_PATH_H
15 #define LLVM_SYSTEM_PATH_H
17 #include "llvm/System/TimeValue.h"
18 #include "llvm/System/IncludeFile.h"
27 /// This structure provides basic file system information about a file. It
28 /// is patterned after the stat(2) Unix operating system call but made
29 /// platform independent and eliminates many of the unix-specific fields.
30 /// However, to support llvm-ar, the mode, user, and group fields are
31 /// retained. These pertain to unix security and may not have a meaningful
32 /// value on non-Unix platforms. However, the other fields fields should
33 /// always be applicable on all platforms. The structure is filled in by
34 /// the PathWithStatus class.
35 /// @brief File status structure
38 uint64_t fileSize; ///< Size of the file in bytes
39 TimeValue modTime; ///< Time of file's modification
40 uint32_t mode; ///< Mode of the file, if applicable
41 uint32_t user; ///< User ID of owner, if applicable
42 uint32_t group; ///< Group ID of owner, if applicable
43 uint64_t uniqueID; ///< A number to uniquely ID this file
44 bool isDir : 1; ///< True if this is a directory.
45 bool isFile : 1; ///< True if this is a file.
47 FileStatus() : fileSize(0), modTime(0,0), mode(0777), user(999),
48 group(999), uniqueID(0), isDir(false), isFile(false) { }
50 TimeValue getTimestamp() const { return modTime; }
51 uint64_t getSize() const { return fileSize; }
52 uint32_t getMode() const { return mode; }
53 uint32_t getUser() const { return user; }
54 uint32_t getGroup() const { return group; }
55 uint64_t getUniqueID() const { return uniqueID; }
58 /// This class provides an abstraction for the path to a file or directory
59 /// in the operating system's filesystem and provides various basic operations
60 /// on it. Note that this class only represents the name of a path to a file
61 /// or directory which may or may not be valid for a given machine's file
62 /// system. The class is patterned after the java.io.File class with various
63 /// extensions and several omissions (not relevant to LLVM). A Path object
64 /// ensures that the path it encapsulates is syntactically valid for the
65 /// operating system it is running on but does not ensure correctness for
66 /// any particular file system. That is, a syntactically valid path might
67 /// specify path components that do not exist in the file system and using
68 /// such a Path to act on the file system could produce errors. There is one
69 /// invalid Path value which is permitted: the empty path. The class should
70 /// never allow a syntactically invalid non-empty path name to be assigned.
71 /// Empty paths are required in order to indicate an error result in some
72 /// situations. If the path is empty, the isValid operation will return
73 /// false. All operations will fail if isValid is false. Operations that
74 /// change the path will either return false if it would cause a syntactically
75 /// invalid path name (in which case the Path object is left unchanged) or
76 /// throw an std::string exception indicating the error. The methods are
77 /// grouped into four basic categories: Path Accessors (provide information
78 /// about the path without accessing disk), Disk Accessors (provide
79 /// information about the underlying file or directory), Path Mutators
80 /// (change the path information, not the disk), and Disk Mutators (change
81 /// the disk file/directory referenced by the path). The Disk Mutator methods
82 /// all have the word "disk" embedded in their method name to reinforce the
83 /// notion that the operation modifies the file system.
85 /// @brief An abstraction for operating system paths.
87 /// @name Constructors
90 /// Construct a path to the root directory of the file system. The root
91 /// directory is a top level directory above which there are no more
92 /// directories. For example, on UNIX, the root directory is /. On Windows
93 /// it is C:\. Other operating systems may have different notions of
94 /// what the root directory is or none at all. In that case, a consistent
95 /// default root directory will be used.
96 static Path GetRootDirectory();
98 /// Construct a path to a unique temporary directory that is created in
99 /// a "standard" place for the operating system. The directory is
100 /// guaranteed to be created on exit from this function. If the directory
101 /// cannot be created, the function will throw an exception.
102 /// @returns an invalid path (empty) on error
103 /// @param ErrMsg Optional place for an error message if an error occurs
104 /// @brief Constrct a path to an new, unique, existing temporary
106 static Path GetTemporaryDirectory(std::string* ErrMsg = 0);
108 /// Construct a vector of sys::Path that contains the "standard" system
109 /// library paths suitable for linking into programs. This function *must*
110 /// return the value of LLVM_LIB_SEARCH_PATH as the first item in \p Paths
111 /// if that environment variable is set and it references a directory.
112 /// @brief Construct a path to the system library directory
113 static void GetSystemLibraryPaths(std::vector<sys::Path>& Paths);
115 /// Construct a vector of sys::Path that contains the "standard" bytecode
116 /// library paths suitable for linking into an llvm program. This function
117 /// *must* return the value of LLVM_LIB_SEARCH_PATH as well as the value
118 /// of LLVM_LIBDIR. It also must provide the System library paths as
119 /// returned by GetSystemLibraryPaths.
120 /// @see GetSystemLibraryPaths
121 /// @brief Construct a list of directories in which bytecode could be
123 static void GetBytecodeLibraryPaths(std::vector<sys::Path>& Paths);
125 /// Find the path to a library using its short name. Use the system
126 /// dependent library paths to locate the library.
127 /// @brief Find a library.
128 static Path FindLibrary(std::string& short_name);
130 /// Construct a path to the default LLVM configuration directory. The
131 /// implementation must ensure that this is a well-known (same on many
132 /// systems) directory in which llvm configuration files exist. For
133 /// example, on Unix, the /etc/llvm directory has been selected.
134 /// @brief Construct a path to the default LLVM configuration directory
135 static Path GetLLVMDefaultConfigDir();
137 /// Construct a path to the LLVM installed configuration directory. The
138 /// implementation must ensure that this refers to the "etc" directory of
139 /// the LLVM installation. This is the location where configuration files
140 /// will be located for a particular installation of LLVM on a machine.
141 /// @brief Construct a path to the LLVM installed configuration directory
142 static Path GetLLVMConfigDir();
144 /// Construct a path to the current user's home directory. The
145 /// implementation must use an operating system specific mechanism for
146 /// determining the user's home directory. For example, the environment
147 /// variable "HOME" could be used on Unix. If a given operating system
148 /// does not have the concept of a user's home directory, this static
149 /// constructor must provide the same result as GetRootDirectory.
150 /// @brief Construct a path to the current user's "home" directory
151 static Path GetUserHomeDirectory();
153 /// Return the suffix commonly used on file names that contain a shared
154 /// object, shared archive, or dynamic link library. Such files are
155 /// linked at runtime into a process and their code images are shared
156 /// between processes.
157 /// @returns The dynamic link library suffix for the current platform.
158 /// @brief Return the dynamic link library suffix.
159 static std::string GetDLLSuffix();
161 /// This is one of the very few ways in which a path can be constructed
162 /// with a syntactically invalid name. The only *legal* invalid name is an
163 /// empty one. Other invalid names are not permitted. Empty paths are
164 /// provided so that they can be used to indicate null or error results in
165 /// other lib/System functionality.
166 /// @brief Construct an empty (and invalid) path.
168 Path(const Path &that) : path(that.path) {}
170 /// This constructor will accept a std::string as a path. No checking is
171 /// done on this path to determine if it is valid. To determine validity
172 /// of the path, use the isValid method.
173 /// @param p The path to assign.
174 /// @brief Construct a Path from a string.
175 explicit Path(const std::string& p) : path(p) {}
181 /// Makes a copy of \p that to \p this.
183 /// @brief Assignment Operator
184 Path &operator=(const Path &that) {
189 /// Compares \p this Path with \p that Path for equality.
190 /// @returns true if \p this and \p that refer to the same thing.
191 /// @brief Equality Operator
192 bool operator==(const Path &that) const {
193 return 0 == path.compare(that.path);
196 /// Compares \p this Path with \p that Path for inequality.
197 /// @returns true if \p this and \p that refer to different things.
198 /// @brief Inequality Operator
199 bool operator!=(const Path &that) const {
200 return 0 != path.compare(that.path);
203 /// Determines if \p this Path is less than \p that Path. This is required
204 /// so that Path objects can be placed into ordered collections (e.g.
205 /// std::map). The comparison is done lexicographically as defined by
206 /// the std::string::compare method.
207 /// @returns true if \p this path is lexicographically less than \p that.
208 /// @brief Less Than Operator
209 bool operator<(const Path& that) const {
210 return 0 > path.compare(that.path);
214 /// @name Path Accessors
217 /// This function will use an operating system specific algorithm to
218 /// determine if the current value of \p this is a syntactically valid
219 /// path name for the operating system. The path name does not need to
220 /// exist, validity is simply syntactical. Empty paths are always invalid.
221 /// @returns true iff the path name is syntactically legal for the
222 /// host operating system.
223 /// @brief Determine if a path is syntactically valid or not.
224 bool isValid() const;
226 /// This function determines if the contents of the path name are empty.
227 /// That is, the path name has a zero length. This does NOT determine if
228 /// if the file is empty. To get the length of the file itself, Use the
229 /// PathWithStatus::getFileStatus() method and then the getSize() method
230 /// on the returned FileStatus object.
231 /// @returns true iff the path is empty.
232 /// @brief Determines if the path name is empty (invalid).
233 bool isEmpty() const { return path.empty(); }
235 /// This function returns the current contents of the path as a
236 /// std::string. This allows the underlying path string to be manipulated.
237 /// @returns std::string containing the path name.
238 /// @brief Returns the path as a std::string.
239 const std::string &toString() const { return path; }
241 /// This function returns the last component of the path name. The last
242 /// component is the file or directory name occuring after the last
243 /// directory separator. If no directory separator is present, the entire
244 /// path name is returned (i.e. same as toString).
245 /// @returns std::string containing the last component of the path name.
246 /// @brief Returns the last component of the path name.
247 std::string getLast() const;
249 /// This function strips off the path and suffix of the file or directory
250 /// name and returns just the basename. For example /a/foo.bar would cause
251 /// this function to return "foo".
252 /// @returns std::string containing the basename of the path
253 /// @brief Get the base name of the path
254 std::string getBasename() const;
256 /// Obtain a 'C' string for the path name.
257 /// @returns a 'C' string containing the path name.
258 /// @brief Returns the path as a C string.
259 const char *const c_str() const { return path.c_str(); }
262 /// @name Disk Accessors
265 /// This function determines if the path name in this object references
266 /// the root (top level directory) of the file system. The details of what
267 /// is considered the "root" may vary from system to system so this method
268 /// will do the necessary checking.
269 /// @returns true iff the path name references the root directory.
270 /// @brief Determines if the path references the root directory.
271 bool isRootDirectory() const;
273 /// This function determines if the path name is absolute, as opposed to
275 /// @breif Determine if the path is absolute.
276 bool isAbsolute() const;
278 /// This function opens the file associated with the path name provided by
279 /// the Path object and reads its magic number. If the magic number at the
280 /// start of the file matches \p magic, true is returned. In all other
281 /// cases (file not found, file not accessible, etc.) it returns false.
282 /// @returns true if the magic number of the file matches \p magic.
283 /// @brief Determine if file has a specific magic number
284 bool hasMagicNumber(const std::string& magic) const;
286 /// This function retrieves the first \p len bytes of the file associated
287 /// with \p this. These bytes are returned as the "magic number" in the
288 /// \p Magic parameter.
289 /// @returns true if the Path is a file and the magic number is retrieved,
291 /// @brief Get the file's magic number.
292 bool getMagicNumber(std::string& Magic, unsigned len) const;
294 /// This function determines if the path name in the object references an
295 /// archive file by looking at its magic number.
296 /// @returns true if the file starts with the magic number for an archive
298 /// @brief Determine if the path references an archive file.
299 bool isArchive() const;
301 /// This function determines if the path name in the object references an
302 /// LLVM Bytecode file by looking at its magic number.
303 /// @returns true if the file starts with the magic number for LLVM
305 /// @brief Determine if the path references a bytecode file.
306 bool isBytecodeFile() const;
308 /// This function determines if the path name in the object references a
309 /// native Dynamic Library (shared library, shared object) by looking at
310 /// the file's magic number. The Path object must reference a file, not a
312 /// @return strue if the file starts with the magid number for a native
314 /// @brief Determine if the path reference a dynamic library.
315 bool isDynamicLibrary() const;
317 /// This function determines if the path name references an existing file
318 /// or directory in the file system.
319 /// @returns true if the pathname references an existing file or
321 /// @brief Determines if the path is a file or directory in
325 /// This function determines if the path name references a readable file
326 /// or directory in the file system. This function checks for
327 /// the existence and readability (by the current program) of the file
329 /// @returns true if the pathname references a readable file.
330 /// @brief Determines if the path is a readable file or directory
331 /// in the file system.
332 bool canRead() const;
334 /// This function determines if the path name references a writable file
335 /// or directory in the file system. This function checks for the
336 /// existence and writability (by the current program) of the file or
338 /// @returns true if the pathname references a writable file.
339 /// @brief Determines if the path is a writable file or directory
340 /// in the file system.
341 bool canWrite() const;
343 /// This function determines if the path name references an executable
344 /// file in the file system. This function checks for the existence and
345 /// executability (by the current program) of the file.
346 /// @returns true if the pathname references an executable file.
347 /// @brief Determines if the path is an executable file in the file
349 bool canExecute() const;
351 /// This function builds a list of paths that are the names of the
352 /// files and directories in a directory.
353 /// @returns true if an error occurs, true otherwise
354 /// @brief Build a list of directory's contents.
355 bool getDirectoryContents(
356 std::set<Path> &paths, ///< The resulting list of file & directory names
357 std::string* ErrMsg ///< Optional place to return an error message.
361 /// @name Path Mutators
364 /// The path name is cleared and becomes empty. This is an invalid
365 /// path name but is the *only* invalid path name. This is provided
366 /// so that path objects can be used to indicate the lack of a
367 /// valid path being found.
368 /// @brief Make the path empty.
369 void clear() { path.clear(); }
371 /// This method sets the Path object to \p unverified_path. This can fail
372 /// if the \p unverified_path does not pass the syntactic checks of the
373 /// isValid() method. If verification fails, the Path object remains
374 /// unchanged and false is returned. Otherwise true is returned and the
375 /// Path object takes on the path value of \p unverified_path
376 /// @returns true if the path was set, false otherwise.
377 /// @param unverified_path The path to be set in Path object.
378 /// @brief Set a full path from a std::string
379 bool set(const std::string& unverified_path);
381 /// One path component is removed from the Path. If only one component is
382 /// present in the path, the Path object becomes empty. If the Path object
383 /// is empty, no change is made.
384 /// @returns false if the path component could not be removed.
385 /// @brief Removes the last directory component of the Path.
386 bool eraseComponent();
388 /// The \p component is added to the end of the Path if it is a legal
389 /// name for the operating system. A directory separator will be added if
391 /// @returns false if the path component could not be added.
392 /// @brief Appends one path component to the Path.
393 bool appendComponent( const std::string& component );
395 /// A period and the \p suffix are appended to the end of the pathname.
396 /// The precondition for this function is that the Path reference a file
397 /// name (i.e. isFile() returns true). If the Path is not a file, no
398 /// action is taken and the function returns false. If the path would
399 /// become invalid for the host operating system, false is returned.
400 /// @returns false if the suffix could not be added, true if it was.
401 /// @brief Adds a period and the \p suffix to the end of the pathname.
402 bool appendSuffix(const std::string& suffix);
404 /// The suffix of the filename is erased. The suffix begins with and
405 /// includes the last . character in the filename after the last directory
406 /// separator and extends until the end of the name. If no . character is
407 /// after the last directory separator, then the file name is left
408 /// unchanged (i.e. it was already without a suffix) but the function
410 /// @returns false if there was no suffix to remove, true otherwise.
411 /// @brief Remove the suffix from a path name.
414 /// The current Path name is made unique in the file system. Upon return,
415 /// the Path will have been changed to make a unique file in the file
416 /// system or it will not have been changed if the current path name is
418 /// @throws std::string if an unrecoverable error occurs.
419 /// @brief Make the current path name unique in the file system.
420 bool makeUnique( bool reuse_current /*= true*/, std::string* ErrMsg );
423 /// @name Disk Mutators
426 /// This method attempts to make the file referenced by the Path object
427 /// available for reading so that the canRead() method will return true.
428 /// @brief Make the file readable;
429 bool makeReadableOnDisk(std::string* ErrMsg = 0);
431 /// This method attempts to make the file referenced by the Path object
432 /// available for writing so that the canWrite() method will return true.
433 /// @brief Make the file writable;
434 bool makeWriteableOnDisk(std::string* ErrMsg = 0);
436 /// This method attempts to make the file referenced by the Path object
437 /// available for execution so that the canExecute() method will return
439 /// @brief Make the file readable;
440 bool makeExecutableOnDisk(std::string* ErrMsg = 0);
442 /// This method allows the last modified time stamp and permission bits
443 /// to be set on the disk object referenced by the Path.
444 /// @throws std::string if an error occurs.
445 /// @returns true on error.
446 /// @brief Set the status information.
447 bool setStatusInfoOnDisk(const FileStatus &SI,
448 std::string *ErrStr = 0) const;
450 /// This method attempts to create a directory in the file system with the
451 /// same name as the Path object. The \p create_parents parameter controls
452 /// whether intermediate directories are created or not. if \p
453 /// create_parents is true, then an attempt will be made to create all
454 /// intermediate directories, as needed. If \p create_parents is false,
455 /// then only the final directory component of the Path name will be
456 /// created. The created directory will have no entries.
457 /// @returns true if the directory could not be created, false otherwise
458 /// @brief Create the directory this Path refers to.
459 bool createDirectoryOnDisk(
460 bool create_parents = false, ///< Determines whether non-existent
461 ///< directory components other than the last one (the "parents")
462 ///< are created or not.
463 std::string* ErrMsg = 0 ///< Optional place to put error messages.
466 /// This method attempts to create a file in the file system with the same
467 /// name as the Path object. The intermediate directories must all exist
468 /// at the time this method is called. Use createDirectoriesOnDisk to
469 /// accomplish that. The created file will be empty upon return from this
471 /// @returns true if the file could not be created, false otherwise.
472 /// @brief Create the file this Path refers to.
473 bool createFileOnDisk(
474 std::string* ErrMsg = 0 ///< Optional place to put error messages.
477 /// This is like createFile except that it creates a temporary file. A
478 /// unique temporary file name is generated based on the contents of
479 /// \p this before the call. The new name is assigned to \p this and the
480 /// file is created. Note that this will both change the Path object
481 /// *and* create the corresponding file. This function will ensure that
482 /// the newly generated temporary file name is unique in the file system.
483 /// @returns true if the file couldn't be created, false otherwise.
484 /// @brief Create a unique temporary file
485 bool createTemporaryFileOnDisk(
486 bool reuse_current = false, ///< When set to true, this parameter
487 ///< indicates that if the current file name does not exist then
488 ///< it will be used without modification.
489 std::string* ErrMsg = 0 ///< Optional place to put error messages
492 /// This method renames the file referenced by \p this as \p newName. The
493 /// file referenced by \p this must exist. The file referenced by
494 /// \p newName does not need to exist.
495 /// @returns true on error, false otherwise
496 /// @brief Rename one file as another.
497 bool renamePathOnDisk(const Path& newName, std::string* ErrMsg);
499 /// This method attempts to destroy the file or directory named by the
500 /// last component of the Path. If the Path refers to a directory and the
501 /// \p destroy_contents is false, an attempt will be made to remove just
502 /// the directory (the final Path component). If \p destroy_contents is
503 /// true, an attempt will be made to remove the entire contents of the
504 /// directory, recursively. If the Path refers to a file, the
505 /// \p destroy_contents parameter is ignored.
506 /// @param destroy_contents Indicates whether the contents of a destroyed
507 /// directory should also be destroyed (recursively).
508 /// @returns false if the file/directory was destroyed, true on error.
509 /// @brief Removes the file or directory from the filesystem.
510 bool eraseFromDisk(bool destroy_contents = false,
511 std::string *Err = 0) const;
516 mutable std::string path; ///< Storage for the path name.
521 /// This class is identical to Path class except it allows you to obtain the
522 /// file status of the Path as well. The reason for the distinction is one of
523 /// efficiency. First, the file status requires additional space and the space
524 /// is incorporated directly into PathWithStatus without an additional malloc.
525 /// Second, obtaining status information is an expensive operation on most
526 /// operating systems so we want to be careful and explicity about where we
527 /// allow this operation in LLVM.
528 /// @brief Path with file status class.
529 class PathWithStatus : public Path {
530 /// @name Constructors
533 /// @brief Default constructor
534 PathWithStatus() : Path(), status(), fsIsValid(false) {}
536 /// @brief Copy constructor
537 PathWithStatus(const PathWithStatus &that)
538 : Path(static_cast<const Path&>(that)), status(that.status),
539 fsIsValid(that.fsIsValid) {}
541 /// This constructor allows construction from a Path object
542 /// @brief Path constructor
543 PathWithStatus(const Path &other)
544 : Path(other), status(), fsIsValid(false) {}
546 /// This constructor will accept a std::string as a path. No checking is
547 /// done on this path to determine if it is valid. To determine validity
548 /// of the path, use the isValid method.
549 /// @param p The path to assign.
550 /// @brief Construct a Path from a string.
551 explicit PathWithStatus(const std::string& p)
552 : Path(p), status(), fsIsValid(false) {}
554 /// Makes a copy of \p that to \p this.
556 /// @brief Assignment Operator
557 PathWithStatus &operator=(const PathWithStatus &that) {
558 static_cast<Path&>(*this) = static_cast<const Path&>(that);
559 status = that.status;
560 fsIsValid = that.fsIsValid;
564 /// Makes a copy of \p that to \p this.
566 /// @brief Assignment Operator
567 PathWithStatus &operator=(const Path &that) {
568 static_cast<Path&>(*this) = static_cast<const Path&>(that);
577 /// This function returns status information about the file. The type of
578 /// path (file or directory) is updated to reflect the actual contents
579 /// of the file system.
580 /// @returns 0 on failure, with Error explaining why (if non-zero)
581 /// @returns a pointer to a FileStatus structure on success.
582 /// @brief Get file status.
583 const FileStatus *getFileStatus(
584 bool forceUpdate = false, ///< Force an update from the file system
585 std::string *Error = 0 ///< Optional place to return an error msg.
592 mutable FileStatus status; ///< Status information.
593 mutable bool fsIsValid; ///< Whether we've obtained it or not
598 /// This enumeration delineates the kinds of files that LLVM knows about.
600 Unknown_FileType = 0, ///< Unrecognized file
601 Bytecode_FileType = 1, ///< Uncompressed bytecode file
602 CompressedBytecode_FileType = 2, ///< Compressed bytecode file
603 Archive_FileType = 3, ///< ar style archive file
604 ELF_FileType = 4, ///< Native ELF object file or lib
605 Mach_O_FileType = 5, ///< Native Mach-O object file or lib
606 COFF_FileType = 6 ///< COFF object file or lib
609 /// This utility function allows any memory block to be examined in order
610 /// to determine its file type.
611 LLVMFileType IdentifyFileType(const char*magic, unsigned length);
613 /// This function can be used to copy the file specified by Src to the
614 /// file specified by Dest. If an error occurs, Dest is removed.
615 /// @returns true if an error occurs, false otherwise
616 /// @brief Copy one file to another.
617 bool CopyFile(const Path& Dest, const Path& Src, std::string* ErrMsg);
620 std::ostream& operator<<(std::ostream& strm, const sys::Path& aPath);
621 inline std::ostream& operator<<(std::ostream& strm,
622 const sys::PathWithStatus& aPath) {
623 strm << static_cast<const sys::Path&>(aPath);
629 FORCE_DEFINING_FILE_TO_BE_LINKED(SystemPath)