1//===- llvm/Support/PathV2.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_PATHV2_H
17#define LLVM_SUPPORT_PATHV2_H
18
19#include "llvm/ADT/SmallString.h"
20#include "llvm/ADT/Twine.h"
21#include "llvm/Support/DataTypes.h"
22#include <iterator>
23
24namespace llvm {
25namespace sys {
26namespace path {
27
28/// @name Lexical Component Iterator
29/// @{
30
31/// @brief Path iterator.
32///
33/// This is a bidirectional iterator that iterates over the individual
34/// components in \a path. The forward traversal order is as follows:
35/// * The root-name element, if present.
36/// * The root-directory element, if present.
37/// * Each successive filename element, if present.
38/// * Dot, if one or more trailing non-root slash characters are present.
39/// The backwards traversal order is the reverse of forward traversal.
40///
41/// Iteration examples. Each component is separated by ',':
42/// @code
43///   /          => /
44///   /foo       => /,foo
45///   foo/       => foo,.
46///   /foo/bar   => /,foo,bar
47///   ../        => ..,.
48///   C:\foo\bar => C:,/,foo,bar
49/// @endcode
50class const_iterator {
51  StringRef Path;      ///< The entire path.
52  StringRef Component; ///< The current component. Not necessarily in Path.
53  size_t    Position;  ///< The iterators current position within Path.
54
55  // An end iterator has Position = Path.size() + 1.
56  friend const_iterator begin(StringRef path);
57  friend const_iterator end(StringRef path);
58
59public:
60  typedef const StringRef value_type;
61  typedef ptrdiff_t difference_type;
62  typedef value_type &reference;
63  typedef value_type *pointer;
64  typedef std::bidirectional_iterator_tag iterator_category;
65
66  reference operator*() const { return Component; }
67  pointer   operator->() const { return &Component; }
68  const_iterator &operator++();    // preincrement
69  const_iterator &operator++(int); // postincrement
70  const_iterator &operator--();    // predecrement
71  const_iterator &operator--(int); // postdecrement
72  bool operator==(const const_iterator &RHS) const;
73  bool operator!=(const const_iterator &RHS) const;
74
75  /// @brief Difference in bytes between this and RHS.
76  ptrdiff_t operator-(const const_iterator &RHS) const;
77};
78
79typedef std::reverse_iterator<const_iterator> reverse_iterator;
80
81/// @brief Get begin iterator over \a path.
82/// @param path Input path.
83/// @returns Iterator initialized with the first component of \a path.
84const_iterator begin(StringRef path);
85
86/// @brief Get end iterator over \a path.
87/// @param path Input path.
88/// @returns Iterator initialized to the end of \a path.
89const_iterator end(StringRef path);
90
91/// @brief Get reverse begin iterator over \a path.
92/// @param path Input path.
93/// @returns Iterator initialized with the first reverse component of \a path.
94inline reverse_iterator rbegin(StringRef path) {
95  return reverse_iterator(end(path));
96}
97
98/// @brief Get reverse end iterator over \a path.
99/// @param path Input path.
100/// @returns Iterator initialized to the reverse end of \a path.
101inline reverse_iterator rend(StringRef path) {
102  return reverse_iterator(begin(path));
103}
104
105/// @}
106/// @name Lexical Modifiers
107/// @{
108
109/// @brief Remove the last component from \a path unless it is the root dir.
110///
111/// @code
112///   directory/filename.cpp => directory/
113///   directory/             => directory
114///   /                      => /
115/// @endcode
116///
117/// @param path A path that is modified to not have a file component.
118void remove_filename(SmallVectorImpl<char> &path);
119
120/// @brief Replace the file extension of \a path with \a extension.
121///
122/// @code
123///   ./filename.cpp => ./filename.extension
124///   ./filename     => ./filename.extension
125///   ./             => ./.extension
126/// @endcode
127///
128/// @param path A path that has its extension replaced with \a extension.
129/// @param extension The extension to be added. It may be empty. It may also
130///                  optionally start with a '.', if it does not, one will be
131///                  prepended.
132void replace_extension(SmallVectorImpl<char> &path, const Twine &extension);
133
134/// @brief Append to path.
135///
136/// @code
137///   /foo  + bar/f => /foo/bar/f
138///   /foo/ + bar/f => /foo/bar/f
139///   foo   + bar/f => foo/bar/f
140/// @endcode
141///
142/// @param path Set to \a path + \a component.
143/// @param a The component to be appended to \a path.
144void append(SmallVectorImpl<char> &path, const Twine &a,
145                                         const Twine &b = "",
146                                         const Twine &c = "",
147                                         const Twine &d = "");
148
149/// @brief Append to path.
150///
151/// @code
152///   /foo  + [bar,f] => /foo/bar/f
153///   /foo/ + [bar,f] => /foo/bar/f
154///   foo   + [bar,f] => foo/bar/f
155/// @endcode
156///
157/// @param path Set to \a path + [\a begin, \a end).
158/// @param begin Start of components to append.
159/// @param end One past the end of components to append.
160void append(SmallVectorImpl<char> &path,
161            const_iterator begin, const_iterator end);
162
163/// @}
164/// @name Transforms (or some other better name)
165/// @{
166
167/// Convert path to the native form. This is used to give paths to users and
168/// operating system calls in the platform's normal way. For example, on Windows
169/// all '/' are converted to '\'.
170///
171/// @param path A path that is transformed to native format.
172/// @param result Holds the result of the transformation.
173void native(const Twine &path, SmallVectorImpl<char> &result);
174
175/// @}
176/// @name Lexical Observers
177/// @{
178
179/// @brief Get root name.
180///
181/// @code
182///   //net/hello => //net
183///   c:/hello    => c: (on Windows, on other platforms nothing)
184///   /hello      => <empty>
185/// @endcode
186///
187/// @param path Input path.
188/// @result The root name of \a path if it has one, otherwise "".
189const StringRef root_name(StringRef path);
190
191/// @brief Get root directory.
192///
193/// @code
194///   /goo/hello => /
195///   c:/hello   => /
196///   d/file.txt => <empty>
197/// @endcode
198///
199/// @param path Input path.
200/// @result The root directory of \a path if it has one, otherwise
201///               "".
202const StringRef root_directory(StringRef path);
203
204/// @brief Get root path.
205///
206/// Equivalent to root_name + root_directory.
207///
208/// @param path Input path.
209/// @result The root path of \a path if it has one, otherwise "".
210const StringRef root_path(StringRef path);
211
212/// @brief Get relative path.
213///
214/// @code
215///   C:\hello\world => hello\world
216///   foo/bar        => foo/bar
217///   /foo/bar       => foo/bar
218/// @endcode
219///
220/// @param path Input path.
221/// @result The path starting after root_path if one exists, otherwise "".
222const StringRef relative_path(StringRef path);
223
224/// @brief Get parent path.
225///
226/// @code
227///   /          => <empty>
228///   /foo       => /
229///   foo/../bar => foo/..
230/// @endcode
231///
232/// @param path Input path.
233/// @result The parent path of \a path if one exists, otherwise "".
234const StringRef parent_path(StringRef path);
235
236/// @brief Get filename.
237///
238/// @code
239///   /foo.txt    => foo.txt
240///   .          => .
241///   ..         => ..
242///   /          => /
243/// @endcode
244///
245/// @param path Input path.
246/// @result The filename part of \a path. This is defined as the last component
247///         of \a path.
248const StringRef filename(StringRef path);
249
250/// @brief Get stem.
251///
252/// If filename contains a dot but not solely one or two dots, result is the
253/// substring of filename ending at (but not including) the last dot. Otherwise
254/// it is filename.
255///
256/// @code
257///   /foo/bar.txt => bar
258///   /foo/bar     => bar
259///   /foo/.txt    => <empty>
260///   /foo/.       => .
261///   /foo/..      => ..
262/// @endcode
263///
264/// @param path Input path.
265/// @result The stem of \a path.
266const StringRef stem(StringRef path);
267
268/// @brief Get extension.
269///
270/// If filename contains a dot but not solely one or two dots, result is the
271/// substring of filename starting at (and including) the last dot, and ending
272/// at the end of \a path. Otherwise "".
273///
274/// @code
275///   /foo/bar.txt => .txt
276///   /foo/bar     => <empty>
277///   /foo/.txt    => .txt
278/// @endcode
279///
280/// @param path Input path.
281/// @result The extension of \a path.
282const StringRef extension(StringRef path);
283
284/// @brief Check whether the given char is a path separator on the host OS.
285///
286/// @param value a character
287/// @result true if \a value is a path separator character on the host OS
288bool is_separator(char value);
289
290/// @brief Get the typical temporary directory for the system, e.g.,
291/// "/var/tmp" or "C:/TEMP"
292///
293/// @param erasedOnReboot Whether to favor a path that is erased on reboot
294/// rather than one that potentially persists longer. This parameter will be
295/// ignored if the user or system has set the typical environment variable
296/// (e.g., TEMP on Windows, TMPDIR on *nix) to specify a temporary directory.
297///
298/// @param result Holds the resulting path name.
299void system_temp_directory(bool erasedOnReboot, SmallVectorImpl<char> &result);
300
301/// @brief Has root name?
302///
303/// root_name != ""
304///
305/// @param path Input path.
306/// @result True if the path has a root name, false otherwise.
307bool has_root_name(const Twine &path);
308
309/// @brief Has root directory?
310///
311/// root_directory != ""
312///
313/// @param path Input path.
314/// @result True if the path has a root directory, false otherwise.
315bool has_root_directory(const Twine &path);
316
317/// @brief Has root path?
318///
319/// root_path != ""
320///
321/// @param path Input path.
322/// @result True if the path has a root path, false otherwise.
323bool has_root_path(const Twine &path);
324
325/// @brief Has relative path?
326///
327/// relative_path != ""
328///
329/// @param path Input path.
330/// @result True if the path has a relative path, false otherwise.
331bool has_relative_path(const Twine &path);
332
333/// @brief Has parent path?
334///
335/// parent_path != ""
336///
337/// @param path Input path.
338/// @result True if the path has a parent path, false otherwise.
339bool has_parent_path(const Twine &path);
340
341/// @brief Has filename?
342///
343/// filename != ""
344///
345/// @param path Input path.
346/// @result True if the path has a filename, false otherwise.
347bool has_filename(const Twine &path);
348
349/// @brief Has stem?
350///
351/// stem != ""
352///
353/// @param path Input path.
354/// @result True if the path has a stem, false otherwise.
355bool has_stem(const Twine &path);
356
357/// @brief Has extension?
358///
359/// extension != ""
360///
361/// @param path Input path.
362/// @result True if the path has a extension, false otherwise.
363bool has_extension(const Twine &path);
364
365/// @brief Is path absolute?
366///
367/// @param path Input path.
368/// @result True if the path is absolute, false if it is not.
369bool is_absolute(const Twine &path);
370
371/// @brief Is path relative?
372///
373/// @param path Input path.
374/// @result True if the path is relative, false if it is not.
375bool is_relative(const Twine &path);
376
377} // end namespace path
378} // end namespace sys
379} // end namespace llvm
380
381#endif
382