LLVM  7.0.0svn
Path.h
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1 //===- llvm/Support/Path.h - Path Operating System Concept ------*- C++ -*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file declares the llvm::sys::path namespace. It is designed after
11 // TR2/boost filesystem (v3), but modified to remove exception handling and the
12 // path class.
13 //
14 //===----------------------------------------------------------------------===//
15 
16 #ifndef LLVM_SUPPORT_PATH_H
17 #define LLVM_SUPPORT_PATH_H
18 
19 #include "llvm/ADT/Twine.h"
20 #include "llvm/ADT/iterator.h"
21 #include "llvm/Support/DataTypes.h"
22 #include <iterator>
23 
24 namespace llvm {
25 namespace sys {
26 namespace path {
27 
28 enum class Style { windows, posix, native };
29 
30 /// @name Lexical Component Iterator
31 /// @{
32 
33 /// @brief Path iterator.
34 ///
35 /// This is an input iterator that iterates over the individual components in
36 /// \a path. The traversal order is as follows:
37 /// * The root-name element, if present.
38 /// * The root-directory element, if present.
39 /// * Each successive filename element, if present.
40 /// * Dot, if one or more trailing non-root slash characters are present.
41 /// Traversing backwards is possible with \a reverse_iterator
42 ///
43 /// Iteration examples. Each component is separated by ',':
44 /// @code
45 /// / => /
46 /// /foo => /,foo
47 /// foo/ => foo,.
48 /// /foo/bar => /,foo,bar
49 /// ../ => ..,.
50 /// C:\foo\bar => C:,/,foo,bar
51 /// @endcode
53  : public iterator_facade_base<const_iterator, std::input_iterator_tag,
54  const StringRef> {
55  StringRef Path; ///< The entire path.
56  StringRef Component; ///< The current component. Not necessarily in Path.
57  size_t Position; ///< The iterators current position within Path.
58  Style S; ///< The path style to use.
59 
60  // An end iterator has Position = Path.size() + 1.
61  friend const_iterator begin(StringRef path, Style style);
62  friend const_iterator end(StringRef path);
63 
64 public:
65  reference operator*() const { return Component; }
66  const_iterator &operator++(); // preincrement
67  bool operator==(const const_iterator &RHS) const;
68 
69  /// @brief Difference in bytes between this and RHS.
70  ptrdiff_t operator-(const const_iterator &RHS) const;
71 };
72 
73 /// @brief Reverse path iterator.
74 ///
75 /// This is an input iterator that iterates over the individual components in
76 /// \a path in reverse order. The traversal order is exactly reversed from that
77 /// of \a const_iterator
79  : public iterator_facade_base<reverse_iterator, std::input_iterator_tag,
80  const StringRef> {
81  StringRef Path; ///< The entire path.
82  StringRef Component; ///< The current component. Not necessarily in Path.
83  size_t Position; ///< The iterators current position within Path.
84  Style S; ///< The path style to use.
85 
86  friend reverse_iterator rbegin(StringRef path, Style style);
87  friend reverse_iterator rend(StringRef path);
88 
89 public:
90  reference operator*() const { return Component; }
91  reverse_iterator &operator++(); // preincrement
92  bool operator==(const reverse_iterator &RHS) const;
93 
94  /// @brief Difference in bytes between this and RHS.
95  ptrdiff_t operator-(const reverse_iterator &RHS) const;
96 };
97 
98 /// @brief Get begin iterator over \a path.
99 /// @param path Input path.
100 /// @returns Iterator initialized with the first component of \a path.
102 
103 /// @brief Get end iterator over \a path.
104 /// @param path Input path.
105 /// @returns Iterator initialized to the end of \a path.
107 
108 /// @brief Get reverse begin iterator over \a path.
109 /// @param path Input path.
110 /// @returns Iterator initialized with the first reverse component of \a path.
112 
113 /// @brief Get reverse end iterator over \a path.
114 /// @param path Input path.
115 /// @returns Iterator initialized to the reverse end of \a path.
117 
118 /// @}
119 /// @name Lexical Modifiers
120 /// @{
121 
122 /// @brief Remove the last component from \a path unless it is the root dir.
123 ///
124 /// @code
125 /// directory/filename.cpp => directory/
126 /// directory/ => directory
127 /// filename.cpp => <empty>
128 /// / => /
129 /// @endcode
130 ///
131 /// @param path A path that is modified to not have a file component.
133 
134 /// @brief Replace the file extension of \a path with \a extension.
135 ///
136 /// @code
137 /// ./filename.cpp => ./filename.extension
138 /// ./filename => ./filename.extension
139 /// ./ => ./.extension
140 /// @endcode
141 ///
142 /// @param path A path that has its extension replaced with \a extension.
143 /// @param extension The extension to be added. It may be empty. It may also
144 /// optionally start with a '.', if it does not, one will be
145 /// prepended.
147  Style style = Style::native);
148 
149 /// @brief Replace matching path prefix with another path.
150 ///
151 /// @code
152 /// /foo, /old, /new => /foo
153 /// /old/foo, /old, /new => /new/foo
154 /// /foo, <empty>, /new => /new/foo
155 /// /old/foo, /old, <empty> => /foo
156 /// @endcode
157 ///
158 /// @param Path If \a Path starts with \a OldPrefix modify to instead
159 /// start with \a NewPrefix.
160 /// @param OldPrefix The path prefix to strip from \a Path.
161 /// @param NewPrefix The path prefix to replace \a NewPrefix with.
163  const StringRef &OldPrefix, const StringRef &NewPrefix,
164  Style style = Style::native);
165 
166 /// @brief Append to path.
167 ///
168 /// @code
169 /// /foo + bar/f => /foo/bar/f
170 /// /foo/ + bar/f => /foo/bar/f
171 /// foo + bar/f => foo/bar/f
172 /// @endcode
173 ///
174 /// @param path Set to \a path + \a component.
175 /// @param a The component to be appended to \a path.
176 void append(SmallVectorImpl<char> &path, const Twine &a,
177  const Twine &b = "",
178  const Twine &c = "",
179  const Twine &d = "");
180 
181 void append(SmallVectorImpl<char> &path, Style style, const Twine &a,
182  const Twine &b = "", const Twine &c = "", const Twine &d = "");
183 
184 /// @brief Append to path.
185 ///
186 /// @code
187 /// /foo + [bar,f] => /foo/bar/f
188 /// /foo/ + [bar,f] => /foo/bar/f
189 /// foo + [bar,f] => foo/bar/f
190 /// @endcode
191 ///
192 /// @param path Set to \a path + [\a begin, \a end).
193 /// @param begin Start of components to append.
194 /// @param end One past the end of components to append.
196  const_iterator end, Style style = Style::native);
197 
198 /// @}
199 /// @name Transforms (or some other better name)
200 /// @{
201 
202 /// Convert path to the native form. This is used to give paths to users and
203 /// operating system calls in the platform's normal way. For example, on Windows
204 /// all '/' are converted to '\'.
205 ///
206 /// @param path A path that is transformed to native format.
207 /// @param result Holds the result of the transformation.
208 void native(const Twine &path, SmallVectorImpl<char> &result,
209  Style style = Style::native);
210 
211 /// Convert path to the native form in place. This is used to give paths to
212 /// users and operating system calls in the platform's normal way. For example,
213 /// on Windows all '/' are converted to '\'.
214 ///
215 /// @param path A path that is transformed to native format.
216 void native(SmallVectorImpl<char> &path, Style style = Style::native);
217 
218 /// @brief Replaces backslashes with slashes if Windows.
219 ///
220 /// @param path processed path
221 /// @result The result of replacing backslashes with forward slashes if Windows.
222 /// On Unix, this function is a no-op because backslashes are valid path
223 /// chracters.
224 std::string convert_to_slash(StringRef path, Style style = Style::native);
225 
226 /// @}
227 /// @name Lexical Observers
228 /// @{
229 
230 /// @brief Get root name.
231 ///
232 /// @code
233 /// //net/hello => //net
234 /// c:/hello => c: (on Windows, on other platforms nothing)
235 /// /hello => <empty>
236 /// @endcode
237 ///
238 /// @param path Input path.
239 /// @result The root name of \a path if it has one, otherwise "".
241 
242 /// @brief Get root directory.
243 ///
244 /// @code
245 /// /goo/hello => /
246 /// c:/hello => /
247 /// d/file.txt => <empty>
248 /// @endcode
249 ///
250 /// @param path Input path.
251 /// @result The root directory of \a path if it has one, otherwise
252 /// "".
254 
255 /// @brief Get root path.
256 ///
257 /// Equivalent to root_name + root_directory.
258 ///
259 /// @param path Input path.
260 /// @result The root path of \a path if it has one, otherwise "".
262 
263 /// @brief Get relative path.
264 ///
265 /// @code
266 /// C:\hello\world => hello\world
267 /// foo/bar => foo/bar
268 /// /foo/bar => foo/bar
269 /// @endcode
270 ///
271 /// @param path Input path.
272 /// @result The path starting after root_path if one exists, otherwise "".
274 
275 /// @brief Get parent path.
276 ///
277 /// @code
278 /// / => <empty>
279 /// /foo => /
280 /// foo/../bar => foo/..
281 /// @endcode
282 ///
283 /// @param path Input path.
284 /// @result The parent path of \a path if one exists, otherwise "".
286 
287 /// @brief Get filename.
288 ///
289 /// @code
290 /// /foo.txt => foo.txt
291 /// . => .
292 /// .. => ..
293 /// / => /
294 /// @endcode
295 ///
296 /// @param path Input path.
297 /// @result The filename part of \a path. This is defined as the last component
298 /// of \a path.
300 
301 /// @brief Get stem.
302 ///
303 /// If filename contains a dot but not solely one or two dots, result is the
304 /// substring of filename ending at (but not including) the last dot. Otherwise
305 /// it is filename.
306 ///
307 /// @code
308 /// /foo/bar.txt => bar
309 /// /foo/bar => bar
310 /// /foo/.txt => <empty>
311 /// /foo/. => .
312 /// /foo/.. => ..
313 /// @endcode
314 ///
315 /// @param path Input path.
316 /// @result The stem of \a path.
318 
319 /// @brief Get extension.
320 ///
321 /// If filename contains a dot but not solely one or two dots, result is the
322 /// substring of filename starting at (and including) the last dot, and ending
323 /// at the end of \a path. Otherwise "".
324 ///
325 /// @code
326 /// /foo/bar.txt => .txt
327 /// /foo/bar => <empty>
328 /// /foo/.txt => .txt
329 /// @endcode
330 ///
331 /// @param path Input path.
332 /// @result The extension of \a path.
334 
335 /// @brief Check whether the given char is a path separator on the host OS.
336 ///
337 /// @param value a character
338 /// @result true if \a value is a path separator character on the host OS
339 bool is_separator(char value, Style style = Style::native);
340 
341 /// @brief Return the preferred separator for this platform.
342 ///
343 /// @result StringRef of the preferred separator, null-terminated.
345 
346 /// @brief Get the typical temporary directory for the system, e.g.,
347 /// "/var/tmp" or "C:/TEMP"
348 ///
349 /// @param erasedOnReboot Whether to favor a path that is erased on reboot
350 /// rather than one that potentially persists longer. This parameter will be
351 /// ignored if the user or system has set the typical environment variable
352 /// (e.g., TEMP on Windows, TMPDIR on *nix) to specify a temporary directory.
353 ///
354 /// @param result Holds the resulting path name.
355 void system_temp_directory(bool erasedOnReboot, SmallVectorImpl<char> &result);
356 
357 /// @brief Get the user's home directory.
358 ///
359 /// @param result Holds the resulting path name.
360 /// @result True if a home directory is set, false otherwise.
362 
363 /// @brief Get the user's cache directory.
364 ///
365 /// Expect the resulting path to be a directory shared with other
366 /// applications/services used by the user. Params \p Path1 to \p Path3 can be
367 /// used to append additional directory names to the resulting path. Recommended
368 /// pattern is <user_cache_directory>/<vendor>/<application>.
369 ///
370 /// @param Result Holds the resulting path.
371 /// @param Path1 Additional path to be appended to the user's cache directory
372 /// path. "" can be used to append nothing.
373 /// @param Path2 Second additional path to be appended.
374 /// @param Path3 Third additional path to be appended.
375 /// @result True if a cache directory path is set, false otherwise.
376 bool user_cache_directory(SmallVectorImpl<char> &Result, const Twine &Path1,
377  const Twine &Path2 = "", const Twine &Path3 = "");
378 
379 /// @brief Has root name?
380 ///
381 /// root_name != ""
382 ///
383 /// @param path Input path.
384 /// @result True if the path has a root name, false otherwise.
385 bool has_root_name(const Twine &path, Style style = Style::native);
386 
387 /// @brief Has root directory?
388 ///
389 /// root_directory != ""
390 ///
391 /// @param path Input path.
392 /// @result True if the path has a root directory, false otherwise.
393 bool has_root_directory(const Twine &path, Style style = Style::native);
394 
395 /// @brief Has root path?
396 ///
397 /// root_path != ""
398 ///
399 /// @param path Input path.
400 /// @result True if the path has a root path, false otherwise.
401 bool has_root_path(const Twine &path, Style style = Style::native);
402 
403 /// @brief Has relative path?
404 ///
405 /// relative_path != ""
406 ///
407 /// @param path Input path.
408 /// @result True if the path has a relative path, false otherwise.
409 bool has_relative_path(const Twine &path, Style style = Style::native);
410 
411 /// @brief Has parent path?
412 ///
413 /// parent_path != ""
414 ///
415 /// @param path Input path.
416 /// @result True if the path has a parent path, false otherwise.
417 bool has_parent_path(const Twine &path, Style style = Style::native);
418 
419 /// @brief Has filename?
420 ///
421 /// filename != ""
422 ///
423 /// @param path Input path.
424 /// @result True if the path has a filename, false otherwise.
425 bool has_filename(const Twine &path, Style style = Style::native);
426 
427 /// @brief Has stem?
428 ///
429 /// stem != ""
430 ///
431 /// @param path Input path.
432 /// @result True if the path has a stem, false otherwise.
433 bool has_stem(const Twine &path, Style style = Style::native);
434 
435 /// @brief Has extension?
436 ///
437 /// extension != ""
438 ///
439 /// @param path Input path.
440 /// @result True if the path has a extension, false otherwise.
441 bool has_extension(const Twine &path, Style style = Style::native);
442 
443 /// @brief Is path absolute?
444 ///
445 /// @param path Input path.
446 /// @result True if the path is absolute, false if it is not.
447 bool is_absolute(const Twine &path, Style style = Style::native);
448 
449 /// @brief Is path relative?
450 ///
451 /// @param path Input path.
452 /// @result True if the path is relative, false if it is not.
453 bool is_relative(const Twine &path, Style style = Style::native);
454 
455 /// @brief Remove redundant leading "./" pieces and consecutive separators.
456 ///
457 /// @param path Input path.
458 /// @result The cleaned-up \a path.
460 
461 /// @brief In-place remove any './' and optionally '../' components from a path.
462 ///
463 /// @param path processed path
464 /// @param remove_dot_dot specify if '../' (except for leading "../") should be
465 /// removed
466 /// @result True if path was changed
467 bool remove_dots(SmallVectorImpl<char> &path, bool remove_dot_dot = false,
468  Style style = Style::native);
469 
470 } // end namespace path
471 } // end namespace sys
472 } // end namespace llvm
473 
474 #endif
bool is_separator(char value, Style style=Style::native)
Check whether the given char is a path separator on the host OS.
Definition: Path.cpp:604
const_iterator end(StringRef path)
Get end iterator over path.
Definition: Path.cpp:245
void remove_filename(SmallVectorImpl< char > &path, Style style=Style::native)
Remove the last component from path unless it is the root dir.
Definition: Path.cpp:485
const_iterator begin(StringRef path, Style style=Style::native)
Get begin iterator over path.
Definition: Path.cpp:236
void replace_path_prefix(SmallVectorImpl< char > &Path, const StringRef &OldPrefix, const StringRef &NewPrefix, Style style=Style::native)
Replace matching path prefix with another path.
Definition: Path.cpp:510
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
reference operator*() const
Definition: Path.h:65
bool has_extension(const Twine &path, Style style=Style::native)
Has extension?
Definition: Path.cpp:667
std::string convert_to_slash(StringRef path, Style style=Style::native)
Replaces backslashes with slashes if Windows.
Definition: Path.cpp:567
StringRef remove_leading_dotslash(StringRef path, Style style=Style::native)
Remove redundant leading "./" pieces and consecutive separators.
Definition: Path.cpp:689
bool has_stem(const Twine &path, Style style=Style::native)
Has stem?
Definition: Path.cpp:660
void append(SmallVectorImpl< char > &path, const Twine &a, const Twine &b="", const Twine &c="", const Twine &d="")
Append to path.
Definition: Path.cpp:466
reverse_iterator rbegin(StringRef path, Style style=Style::native)
Get reverse begin iterator over path.
Definition: Path.cpp:307
Twine - A lightweight data structure for efficiently representing the concatenation of temporary valu...
Definition: Twine.h:81
bool is_absolute(const Twine &path, Style style=Style::native)
Is path absolute?
Definition: Path.cpp:674
StringRef root_path(StringRef path, Style style=Style::native)
Get root path.
Definition: Path.cpp:357
CRTP base class which implements the entire standard iterator facade in terms of a minimal subset of ...
Definition: iterator.h:68
bool has_parent_path(const Twine &path, Style style=Style::native)
Has parent path?
Definition: Path.cpp:653
bool has_filename(const Twine &path, Style style=Style::native)
Has filename?
Definition: Path.cpp:646
bool user_cache_directory(SmallVectorImpl< char > &Result, const Twine &Path1, const Twine &Path2="", const Twine &Path3="")
Get the user&#39;s cache directory.
Definition: Path.cpp:1169
StringRef parent_path(StringRef path, Style style=Style::native)
Get parent path.
Definition: Path.cpp:477
StringRef get_separator(Style style=Style::native)
Return the preferred separator for this platform.
Definition: Path.cpp:612
StringRef root_directory(StringRef path, Style style=Style::native)
Get root directory.
Definition: Path.cpp:400
void replace_extension(SmallVectorImpl< char > &path, const Twine &extension, Style style=Style::native)
Replace the file extension of path with extension.
Definition: Path.cpp:491
bool remove_dots(SmallVectorImpl< char > &path, bool remove_dot_dot=false, Style style=Style::native)
In-place remove any &#39;.
Definition: Path.cpp:727
StringRef root_name(StringRef path, Style style=Style::native)
Get root name.
Definition: Path.cpp:383
reference operator*() const
Definition: Path.h:90
bool has_root_directory(const Twine &path, Style style=Style::native)
Has root directory?
Definition: Path.cpp:625
Path iterator.
Definition: Path.h:52
Reverse path iterator.
Definition: Path.h:78
bool has_root_path(const Twine &path, Style style=Style::native)
Has root path?
Definition: Path.cpp:632
bool has_relative_path(const Twine &path, Style style=Style::native)
Has relative path?
Definition: Path.cpp:639
StringRef filename(StringRef path, Style style=Style::native)
Get filename.
Definition: Path.cpp:576
bool is_relative(const Twine &path, Style style=Style::native)
Is path relative?
Definition: Path.cpp:685
APInt operator-(APInt)
Definition: APInt.h:2023
reverse_iterator rend(StringRef path)
Get reverse end iterator over path.
Definition: Path.cpp:315
void system_temp_directory(bool erasedOnReboot, SmallVectorImpl< char > &result)
Get the typical temporary directory for the system, e.g., "/var/tmp" or "C:/TEMP".
StringRef relative_path(StringRef path, Style style=Style::native)
Get relative path.
Definition: Path.cpp:423
bool home_directory(SmallVectorImpl< char > &result)
Get the user&#39;s home directory.
StringRef stem(StringRef path, Style style=Style::native)
Get stem.
Definition: Path.cpp:578
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:49
bool operator==(uint64_t V1, const APInt &V2)
Definition: APInt.h:1946
bool has_root_name(const Twine &path, Style style=Style::native)
Has root name?
Definition: Path.cpp:618
StringRef extension(StringRef path, Style style=Style::native)
Get extension.
Definition: Path.cpp:591