1 //===-- FileSpec.h ----------------------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #ifndef LLDB_UTILITY_FILESPEC_H
10 #define LLDB_UTILITY_FILESPEC_H
11 
12 #include <functional>
13 #include <optional>
14 #include <string>
15 
16 #include "lldb/Utility/ConstString.h"
17 
18 #include "llvm/ADT/StringRef.h"
19 #include "llvm/Support/FileSystem.h"
20 #include "llvm/Support/FormatVariadic.h"
21 #include "llvm/Support/Path.h"
22 
23 #include <cstddef>
24 #include <cstdint>
25 
26 namespace lldb_private {
27 class Stream;
28 }
29 namespace llvm {
30 class Triple;
31 }
32 namespace llvm {
33 class raw_ostream;
34 }
35 namespace llvm {
36 template <typename T> class SmallVectorImpl;
37 }
38 
39 namespace lldb_private {
40 
41 /// \class FileSpec FileSpec.h "lldb/Utility/FileSpec.h"
42 /// A file utility class.
43 ///
44 /// A file specification class that divides paths up into a directory
45 /// and basename. These string values of the paths are put into uniqued string
46 /// pools for fast comparisons and efficient memory usage.
47 ///
48 /// Another reason the paths are split into the directory and basename is to
49 /// allow efficient debugger searching. Often in a debugger the user types in
50 /// the basename of the file, for example setting a breakpoint by file and
51 /// line, or specifying a module (shared library) to limit the scope in which
52 /// to execute a command. The user rarely types in a full path. When the paths
53 /// are already split up, it makes it easy for us to compare only the
54 /// basenames of a lot of file specifications without having to split up the
55 /// file path each time to get to the basename.
56 class FileSpec {
57 public:
58   using Style = llvm::sys::path::Style;
59 
60   FileSpec();
61 
62   /// Constructor with path.
63   ///
64   /// Takes a path to a file which can be just a filename, or a full path. If
65   /// \a path is not nullptr or empty, this function will call
66   /// FileSpec::SetFile (const char *path).
67   ///
68   /// \param[in] path
69   ///     The full or partial path to a file.
70   ///
71   /// \param[in] style
72   ///     The style of the path
73   ///
74   /// \see FileSpec::SetFile (const char *path)
75   explicit FileSpec(llvm::StringRef path, Style style = Style::native);
76 
77   explicit FileSpec(llvm::StringRef path, const llvm::Triple &triple);
78 
79   bool DirectoryEquals(const FileSpec &other) const;
80 
81   bool FileEquals(const FileSpec &other) const;
82 
83   /// Equal to operator
84   ///
85   /// Tests if this object is equal to \a rhs.
86   ///
87   /// \param[in] rhs
88   ///     A const FileSpec object reference to compare this object
89   ///     to.
90   ///
91   /// \return
92   ///     \b true if this object is equal to \a rhs, \b false
93   ///     otherwise.
94   bool operator==(const FileSpec &rhs) const;
95 
96   /// Not equal to operator
97   ///
98   /// Tests if this object is not equal to \a rhs.
99   ///
100   /// \param[in] rhs
101   ///     A const FileSpec object reference to compare this object
102   ///     to.
103   ///
104   /// \return
105   ///     \b true if this object is equal to \a rhs, \b false
106   ///     otherwise.
107   bool operator!=(const FileSpec &rhs) const;
108 
109   /// Less than to operator
110   ///
111   /// Tests if this object is less than \a rhs.
112   ///
113   /// \param[in] rhs
114   ///     A const FileSpec object reference to compare this object
115   ///     to.
116   ///
117   /// \return
118   ///     \b true if this object is less than \a rhs, \b false
119   ///     otherwise.
120   bool operator<(const FileSpec &rhs) const;
121 
122   /// Convert to pointer operator.
123   ///
124   /// This allows code to check a FileSpec object to see if it contains
125   /// anything valid using code such as:
126   ///
127   /// \code
128   /// FileSpec file_spec(...);
129   /// if (file_spec)
130   /// { ...
131   /// \endcode
132   ///
133   /// \return
134   ///     A pointer to this object if either the directory or filename
135   ///     is valid, nullptr otherwise.
136   explicit operator bool() const;
137 
138   /// Logical NOT operator.
139   ///
140   /// This allows code to check a FileSpec object to see if it is invalid
141   /// using code such as:
142   ///
143   /// \code
144   /// FileSpec file_spec(...);
145   /// if (!file_spec)
146   /// { ...
147   /// \endcode
148   ///
149   /// \return
150   ///     Returns \b true if the object has an empty directory and
151   ///     filename, \b false otherwise.
152   bool operator!() const;
153 
154   /// Clears the object state.
155   ///
156   /// Clear this object by releasing both the directory and filename string
157   /// values and reverting them to empty strings.
158   void Clear();
159 
160   /// Compare two FileSpec objects.
161   ///
162   /// If \a full is true, then both the directory and the filename must match.
163   /// If \a full is false, then the directory names for \a lhs and \a rhs are
164   /// only compared if they are both not empty. This allows a FileSpec object
165   /// to only contain a filename and it can match FileSpec objects that have
166   /// matching filenames with different paths.
167   ///
168   /// \param[in] lhs
169   ///     A const reference to the Left Hand Side object to compare.
170   ///
171   /// \param[in] rhs
172   ///     A const reference to the Right Hand Side object to compare.
173   ///
174   /// \param[in] full
175   ///     If true, then both the directory and filenames will have to
176   ///     match for a compare to return zero (equal to). If false
177   ///     and either directory from \a lhs or \a rhs is empty, then
178   ///     only the filename will be compared, else a full comparison
179   ///     is done.
180   ///
181   /// \return -1 if \a lhs is less than \a rhs, 0 if \a lhs is equal to \a rhs,
182   ///     1 if \a lhs is greater than \a rhs
183   static int Compare(const FileSpec &lhs, const FileSpec &rhs, bool full);
184 
185   static bool Equal(const FileSpec &a, const FileSpec &b, bool full);
186 
187   /// Match FileSpec \a pattern against FileSpec \a file. If \a pattern has a
188   /// directory component, then the \a file must have the same directory
189   /// component. Otherwise, just it matches just the filename. An empty \a
190   /// pattern matches everything.
191   static bool Match(const FileSpec &pattern, const FileSpec &file);
192 
193   /// Attempt to guess path style for a given path string. It returns a style,
194   /// if it was able to make a reasonable guess, or std::nullopt if it wasn't.
195   /// The guess will be correct if the input path was a valid absolute path on
196   /// the system which produced it. On other paths the result of this function
197   /// is unreliable (e.g. "c:\foo.txt" is a valid relative posix path).
198   static std::optional<Style> GuessPathStyle(llvm::StringRef absolute_path);
199 
200   /// Case sensitivity of path.
201   ///
202   /// \return
203   ///     \b true if the file path is case sensitive (POSIX), false
204   ///		if case insensitive (Windows).
205   bool IsCaseSensitive() const { return is_style_posix(m_style); }
206 
207   /// Dump this object to a Stream.
208   ///
209   /// Dump the object to the supplied stream \a s. If the object contains a
210   /// valid directory name, it will be displayed followed by a directory
211   /// delimiter, and the filename.
212   ///
213   /// \param[in] s
214   ///     The stream to which to dump the object description.
215   void Dump(llvm::raw_ostream &s) const;
216 
217   Style GetPathStyle() const;
218 
219   /// Directory string const get accessor.
220   ///
221   /// \return
222   ///     A const reference to the directory string object.
223   const ConstString &GetDirectory() const { return m_directory; }
224 
225   /// Directory string set accessor.
226   ///
227   /// \param[in] directory
228   ///     The value to replace the directory with.
229   void SetDirectory(ConstString directory);
230   void SetDirectory(llvm::StringRef directory);
231 
232   /// Clear the directory in this object.
233   void ClearDirectory();
234 
235 
236   /// Filename string const get accessor.
237   ///
238   /// \return
239   ///     A const reference to the filename string object.
240   const ConstString &GetFilename() const { return m_filename; }
241 
242   /// Filename string set accessor.
243   ///
244   /// \param[in] filename
245   ///     The const string to replace the directory with.
246   void SetFilename(ConstString filename);
247   void SetFilename(llvm::StringRef filename);
248 
249   /// Clear the filename in this object.
250   void ClearFilename();
251 
252   /// Returns true if the filespec represents an implementation source file
253   /// (files with a ".c", ".cpp", ".m", ".mm" (many more) extension).
254   ///
255   /// \return
256   ///     \b true if the FileSpec represents an implementation source
257   ///     file, \b false otherwise.
258   bool IsSourceImplementationFile() const;
259 
260   /// Returns true if the filespec represents a relative path.
261   ///
262   /// \return
263   ///     \b true if the filespec represents a relative path,
264   ///     \b false otherwise.
265   bool IsRelative() const;
266 
267   /// Returns true if the filespec represents an absolute path.
268   ///
269   /// \return
270   ///     \b true if the filespec represents an absolute path,
271   ///     \b false otherwise.
272   bool IsAbsolute() const;
273 
274   /// Make the FileSpec absolute by treating it relative to \a dir. Absolute
275   /// FileSpecs are never changed by this function.
276   void MakeAbsolute(const FileSpec &dir);
277 
278   /// Temporary helper for FileSystem change.
279   void SetPath(llvm::StringRef p) { SetFile(p); }
280 
281   /// Extract the full path to the file.
282   ///
283   /// Extract the directory and path into a fixed buffer. This is needed as
284   /// the directory and path are stored in separate string values.
285   ///
286   /// \param[out] path
287   ///     The buffer in which to place the extracted full path.
288   ///
289   /// \param[in] max_path_length
290   ///     The maximum length of \a path.
291   ///
292   /// \return
293   ///     Returns the number of characters that would be needed to
294   ///     properly copy the full path into \a path. If the returned
295   ///     number is less than \a max_path_length, then the path is
296   ///     properly copied and terminated. If the return value is
297   ///     >= \a max_path_length, then the path was truncated (but is
298   ///     still NULL terminated).
299   size_t GetPath(char *path, size_t max_path_length,
300                  bool denormalize = true) const;
301 
302   /// Extract the full path to the file.
303   ///
304   /// Extract the directory and path into a std::string, which is returned.
305   ///
306   /// \return
307   ///     Returns a std::string with the directory and filename
308   ///     concatenated.
309   std::string GetPath(bool denormalize = true) const;
310 
311   /// Get the full path as a ConstString.
312   ///
313   /// This method should only be used when you need a ConstString or the
314   /// const char * from a ConstString to ensure permanent lifetime of C string.
315   /// Anyone needing the path temporarily should use the GetPath() method that
316   /// returns a std:string.
317   ConstString GetPathAsConstString(bool denormalize = true) const;
318 
319   /// Extract the full path to the file.
320   ///
321   /// Extract the directory and path into an llvm::SmallVectorImpl<>
322   void GetPath(llvm::SmallVectorImpl<char> &path,
323                bool denormalize = true) const;
324 
325   /// Extract the extension of the file.
326   ///
327   /// Returns a ConstString that represents the extension of the filename for
328   /// this FileSpec object. If this object does not represent a file, or the
329   /// filename has no extension, ConstString(nullptr) is returned. The dot
330   /// ('.') character is the first character in the returned string.
331   ///
332   /// \return Returns the extension of the file as a StringRef.
333   llvm::StringRef GetFileNameExtension() const;
334 
335   /// Return the filename without the extension part
336   ///
337   /// Returns a ConstString that represents the filename of this object
338   /// without the extension part (e.g. for a file named "foo.bar", "foo" is
339   /// returned)
340   ///
341   /// \return Returns the filename without extension as a ConstString object.
342   ConstString GetFileNameStrippingExtension() const;
343 
344   /// Get the memory cost of this object.
345   ///
346   /// Return the size in bytes that this object takes in memory. This returns
347   /// the size in bytes of this object, not any shared string values it may
348   /// refer to.
349   ///
350   /// \return
351   ///     The number of bytes that this object occupies in memory.
352   size_t MemorySize() const;
353 
354   /// Change the file specified with a new path.
355   ///
356   /// Update the contents of this object with a new path. The path will be
357   /// split up into a directory and filename and stored as uniqued string
358   /// values for quick comparison and efficient memory usage.
359   ///
360   /// \param[in] path
361   ///     A full, partial, or relative path to a file.
362   ///
363   /// \param[in] style
364   ///     The style for the given path.
365   void SetFile(llvm::StringRef path, Style style);
366 
367   /// Change the file specified with a new path.
368   ///
369   /// Update the contents of this object with a new path. The path will be
370   /// split up into a directory and filename and stored as uniqued string
371   /// values for quick comparison and efficient memory usage.
372   ///
373   /// \param[in] path
374   ///     A full, partial, or relative path to a file.
375   ///
376   /// \param[in] triple
377   ///     The triple which is used to set the Path style.
378   void SetFile(llvm::StringRef path, const llvm::Triple &triple);
379 
380   bool IsResolved() const { return m_is_resolved; }
381 
382   /// Set if the file path has been resolved or not.
383   ///
384   /// If you know a file path is already resolved and avoided passing a \b
385   /// true parameter for any functions that take a "bool resolve_path"
386   /// parameter, you can set the value manually using this call to make sure
387   /// we don't try and resolve it later, or try and resolve a path that has
388   /// already been resolved.
389   ///
390   /// \param[in] is_resolved
391   ///     A boolean value that will replace the current value that
392   ///     indicates if the paths in this object have been resolved.
393   void SetIsResolved(bool is_resolved) { m_is_resolved = is_resolved; }
394 
395   FileSpec CopyByAppendingPathComponent(llvm::StringRef component) const;
396   FileSpec CopyByRemovingLastPathComponent() const;
397 
398   void PrependPathComponent(llvm::StringRef component);
399   void PrependPathComponent(const FileSpec &new_path);
400 
401   void AppendPathComponent(llvm::StringRef component);
402   void AppendPathComponent(const FileSpec &new_path);
403 
404   /// Removes the last path component by replacing the current path with its
405   /// parent. When the current path has no parent, this is a no-op.
406   ///
407   /// \return
408   ///     A boolean value indicating whether the path was updated.
409   bool RemoveLastPathComponent();
410 
411   /// Gets the components of the FileSpec's path.
412   /// For example, given the path:
413   ///   /System/Library/PrivateFrameworks/UIFoundation.framework/UIFoundation
414   ///
415   /// This function returns:
416   ///   {"System", "Library", "PrivateFrameworks", "UIFoundation.framework",
417   ///   "UIFoundation"}
418   /// \return
419   ///   A std::vector of llvm::StringRefs for each path component.
420   ///   The lifetime of the StringRefs is tied to the lifetime of the FileSpec.
421   std::vector<llvm::StringRef> GetComponents() const;
422 
423 protected:
424   // Convenience method for setting the file without changing the style.
425   void SetFile(llvm::StringRef path);
426 
427   /// Called anytime m_directory or m_filename is changed to clear any cached
428   /// state in this object.
429   void PathWasModified() {
430     m_is_resolved = false;
431     m_absolute = Absolute::Calculate;
432   }
433 
434   enum class Absolute : uint8_t {
435     Calculate,
436     Yes,
437     No
438   };
439 
440   // Member variables
441   ConstString m_directory;            ///< The uniqued directory path
442   ConstString m_filename;             ///< The uniqued filename path
443   mutable bool m_is_resolved = false; ///< True if this path has been resolved.
444   mutable Absolute m_absolute = Absolute::Calculate; ///< Cache absoluteness.
445   Style m_style; ///< The syntax that this path uses (e.g. Windows / Posix)
446 };
447 
448 /// Dump a FileSpec object to a stream
449 Stream &operator<<(Stream &s, const FileSpec &f);
450 } // namespace lldb_private
451 
452 namespace llvm {
453 
454 /// Implementation of format_provider<T> for FileSpec.
455 ///
456 /// The options string of a FileSpec has the grammar:
457 ///
458 ///   file_spec_options   :: (empty) | F | D
459 ///
460 ///   =======================================================
461 ///   |  style  |     Meaning          |      Example       |
462 ///   -------------------------------------------------------
463 ///   |         |                      |  Input   |  Output |
464 ///   =======================================================
465 ///   |    F    | Only print filename  | /foo/bar |   bar   |
466 ///   |    D    | Only print directory | /foo/bar |  /foo/  |
467 ///   | (empty) | Print file and dir   |          |         |
468 ///   =======================================================
469 ///
470 /// Any other value is considered an invalid format string.
471 ///
472 template <> struct format_provider<lldb_private::FileSpec> {
473   static void format(const lldb_private::FileSpec &F, llvm::raw_ostream &Stream,
474                      StringRef Style);
475 };
476 
477 } // namespace llvm
478 
479 #endif // LLDB_UTILITY_FILESPEC_H
480