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