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#include <system_error>
24
25namespace llvm {
26namespace sys {
27namespace path {
28
29enum class Style { windows, posix, native };
30
31/// @name Lexical Component Iterator
32/// @{
33
34/// Path iterator.
35///
36/// This is an input iterator that iterates over the individual components in
37/// \a path. The traversal order is as follows:
38/// * The root-name element, if present.
39/// * The root-directory element, if present.
40/// * Each successive filename element, if present.
41/// * Dot, if one or more trailing non-root slash characters are present.
42/// Traversing backwards is possible with \a reverse_iterator
43///
44/// Iteration examples. Each component is separated by ',':
45/// @code
46/// / => /
47/// /foo => /,foo
48/// foo/ => foo,.
49/// /foo/bar => /,foo,bar
50/// ../ => ..,.
51/// C:\foo\bar => C:,/,foo,bar
52/// @endcode
53class const_iterator
54 : public iterator_facade_base<const_iterator, std::input_iterator_tag,
55 const StringRef> {
56 StringRef Path; ///< The entire path.
57 StringRef Component; ///< The current component. Not necessarily in Path.
58 size_t Position; ///< The iterators current position within Path.
59 Style S; ///< The path style to use.
60
61 // An end iterator has Position = Path.size() + 1.
62 friend const_iterator begin(StringRef path, Style style);
63 friend const_iterator end(StringRef path);
64
65public:
66 reference operator*() const { return Component; }
67 const_iterator &operator++(); // preincrement
68 bool operator==(const const_iterator &RHS) const;
69
70 /// Difference in bytes between this and RHS.
71 ptrdiff_t operator-(const const_iterator &RHS) const;
72};
73
74/// Reverse path iterator.
75///
76/// This is an input iterator that iterates over the individual components in
77/// \a path in reverse order. The traversal order is exactly reversed from that
78/// of \a const_iterator
79class reverse_iterator
80 : public iterator_facade_base<reverse_iterator, std::input_iterator_tag,
81 const StringRef> {
82 StringRef Path; ///< The entire path.
83 StringRef Component; ///< The current component. Not necessarily in Path.
84 size_t Position; ///< The iterators current position within Path.
85 Style S; ///< The path style to use.
86
87 friend reverse_iterator rbegin(StringRef path, Style style);
88 friend reverse_iterator rend(StringRef path);
89
90public:
91 reference operator*() const { return Component; }
92 reverse_iterator &operator++(); // preincrement
93 bool operator==(const reverse_iterator &RHS) const;
94
95 /// Difference in bytes between this and RHS.
96 ptrdiff_t operator-(const reverse_iterator &RHS) const;
97};
98
99/// Get begin iterator over \a path.
100/// @param path Input path.
101/// @returns Iterator initialized with the first component of \a path.
102const_iterator begin(StringRef path, Style style = Style::native);
103
104/// Get end iterator over \a path.
105/// @param path Input path.
106/// @returns Iterator initialized to the end of \a path.
107const_iterator end(StringRef path);
108
109/// Get reverse begin iterator over \a path.
110/// @param path Input path.
111/// @returns Iterator initialized with the first reverse component of \a path.
112reverse_iterator rbegin(StringRef path, Style style = Style::native);
113
114/// Get reverse end iterator over \a path.
115/// @param path Input path.
116/// @returns Iterator initialized to the reverse end of \a path.
117reverse_iterator rend(StringRef path);
118
119/// @}
120/// @name Lexical Modifiers
121/// @{
122
123/// Remove the last component from \a path unless it is the root dir.
124///
125/// @code
126/// directory/filename.cpp => directory/
127/// directory/ => directory
128/// filename.cpp => <empty>
129/// / => /
130/// @endcode
131///
132/// @param path A path that is modified to not have a file component.
133void remove_filename(SmallVectorImpl<char> &path, Style style = Style::native);
134
135/// Replace the file extension of \a path with \a extension.
136///
137/// @code
138/// ./filename.cpp => ./filename.extension
139/// ./filename => ./filename.extension
140/// ./ => ./.extension
141/// @endcode
142///
143/// @param path A path that has its extension replaced with \a extension.
144/// @param extension The extension to be added. It may be empty. It may also
145/// optionally start with a '.', if it does not, one will be
146/// prepended.
147void replace_extension(SmallVectorImpl<char> &path, const Twine &extension,
148 Style style = Style::native);
149
150/// Replace matching path prefix with another path.
151///
152/// @code
153/// /foo, /old, /new => /foo
154/// /old/foo, /old, /new => /new/foo
155/// /foo, <empty>, /new => /new/foo
156/// /old/foo, /old, <empty> => /foo
157/// @endcode
158///
159/// @param Path If \a Path starts with \a OldPrefix modify to instead
160/// start with \a NewPrefix.
161/// @param OldPrefix The path prefix to strip from \a Path.
162/// @param NewPrefix The path prefix to replace \a NewPrefix with.
163void replace_path_prefix(SmallVectorImpl<char> &Path,
164 const StringRef &OldPrefix, const StringRef &NewPrefix,
165 Style style = Style::native);
166
167/// Append to path.
168///
169/// @code
170/// /foo + bar/f => /foo/bar/f
171/// /foo/ + bar/f => /foo/bar/f
172/// foo + bar/f => foo/bar/f
173/// @endcode
174///
175/// @param path Set to \a path + \a component.
176/// @param a The component to be appended to \a path.
177void append(SmallVectorImpl<char> &path, const Twine &a,
178 const Twine &b = "",
179 const Twine &c = "",
180 const Twine &d = "");
181
182void append(SmallVectorImpl<char> &path, Style style, const Twine &a,
183 const Twine &b = "", const Twine &c = "", const Twine &d = "");
184
185/// Append to path.
186///
187/// @code
188/// /foo + [bar,f] => /foo/bar/f
189/// /foo/ + [bar,f] => /foo/bar/f
190/// foo + [bar,f] => foo/bar/f
191/// @endcode
192///
193/// @param path Set to \a path + [\a begin, \a end).
194/// @param begin Start of components to append.
195/// @param end One past the end of components to append.
196void append(SmallVectorImpl<char> &path, const_iterator begin,
197 const_iterator end, Style style = Style::native);
198
199/// @}
200/// @name Transforms (or some other better name)
201/// @{
202
203/// Convert path to the native form. This is used to give paths to users and
204/// operating system calls in the platform's normal way. For example, on Windows
205/// all '/' are converted to '\'.
206///
207/// @param path A path that is transformed to native format.
208/// @param result Holds the result of the transformation.
209void native(const Twine &path, SmallVectorImpl<char> &result,
210 Style style = Style::native);
211
212/// Convert path to the native form in place. This is used to give paths to
213/// users and operating system calls in the platform's normal way. For example,
214/// on Windows all '/' are converted to '\'.
215///
216/// @param path A path that is transformed to native format.
217void native(SmallVectorImpl<char> &path, Style style = Style::native);
218
219/// Replaces backslashes with slashes if Windows.
220///
221/// @param path processed path
222/// @result The result of replacing backslashes with forward slashes if Windows.
223/// On Unix, this function is a no-op because backslashes are valid path
224/// chracters.
225std::string convert_to_slash(StringRef path, Style style = Style::native);
226
227/// @}
228/// @name Lexical Observers
229/// @{
230
231/// Get root name.
232///
233/// @code
234/// //net/hello => //net
235/// c:/hello => c: (on Windows, on other platforms nothing)
236/// /hello => <empty>
237/// @endcode
238///
239/// @param path Input path.
240/// @result The root name of \a path if it has one, otherwise "".
241StringRef root_name(StringRef path, Style style = Style::native);
242
243/// Get root directory.
244///
245/// @code
246/// /goo/hello => /
247/// c:/hello => /
248/// d/file.txt => <empty>
249/// @endcode
250///
251/// @param path Input path.
252/// @result The root directory of \a path if it has one, otherwise
253/// "".
254StringRef root_directory(StringRef path, Style style = Style::native);
255
256/// Get root path.
257///
258/// Equivalent to root_name + root_directory.
259///
260/// @param path Input path.
261/// @result The root path of \a path if it has one, otherwise "".
262StringRef root_path(StringRef path, Style style = Style::native);
263
264/// Get relative path.
265///
266/// @code
267/// C:\hello\world => hello\world
268/// foo/bar => foo/bar
269/// /foo/bar => foo/bar
270/// @endcode
271///
272/// @param path Input path.
273/// @result The path starting after root_path if one exists, otherwise "".
274StringRef relative_path(StringRef path, Style style = Style::native);
275
276/// Get parent path.
277///
278/// @code
279/// / => <empty>
280/// /foo => /
281/// foo/../bar => foo/..
282/// @endcode
283///
284/// @param path Input path.
285/// @result The parent path of \a path if one exists, otherwise "".
286StringRef parent_path(StringRef path, Style style = Style::native);
287
288/// Get filename.
289///
290/// @code
291/// /foo.txt => foo.txt
292/// . => .
293/// .. => ..
294/// / => /
295/// @endcode
296///
297/// @param path Input path.
298/// @result The filename part of \a path. This is defined as the last component
299/// of \a path.
300StringRef filename(StringRef path, Style style = Style::native);
301
302/// Get stem.
303///
304/// If filename contains a dot but not solely one or two dots, result is the
305/// substring of filename ending at (but not including) the last dot. Otherwise
306/// it is filename.
307///
308/// @code
309/// /foo/bar.txt => bar
310/// /foo/bar => bar
311/// /foo/.txt => <empty>
312/// /foo/. => .
313/// /foo/.. => ..
314/// @endcode
315///
316/// @param path Input path.
317/// @result The stem of \a path.
318StringRef stem(StringRef path, Style style = Style::native);
319
320/// Get extension.
321///
322/// If filename contains a dot but not solely one or two dots, result is the
323/// substring of filename starting at (and including) the last dot, and ending
324/// at the end of \a path. Otherwise "".
325///
326/// @code
327/// /foo/bar.txt => .txt
328/// /foo/bar => <empty>
329/// /foo/.txt => .txt
330/// @endcode
331///
332/// @param path Input path.
333/// @result The extension of \a path.
334StringRef extension(StringRef path, Style style = Style::native);
335
336/// Check whether the given char is a path separator on the host OS.
337///
338/// @param value a character
339/// @result true if \a value is a path separator character on the host OS
340bool is_separator(char value, Style style = Style::native);
341
342/// Return the preferred separator for this platform.
343///
344/// @result StringRef of the preferred separator, null-terminated.
345StringRef get_separator(Style style = Style::native);
346
347/// Get the typical temporary directory for the system, e.g.,
348/// "/var/tmp" or "C:/TEMP"
349///
350/// @param erasedOnReboot Whether to favor a path that is erased on reboot
351/// rather than one that potentially persists longer. This parameter will be
352/// ignored if the user or system has set the typical environment variable
353/// (e.g., TEMP on Windows, TMPDIR on *nix) to specify a temporary directory.
354///
355/// @param result Holds the resulting path name.
356void system_temp_directory(bool erasedOnReboot, SmallVectorImpl<char> &result);
357
358/// Get the user's home directory.
359///
360/// @param result Holds the resulting path name.
361/// @result True if a home directory is set, false otherwise.
362bool home_directory(SmallVectorImpl<char> &result);
363
364/// Has root name?
365///
366/// root_name != ""
367///
368/// @param path Input path.
369/// @result True if the path has a root name, false otherwise.
370bool has_root_name(const Twine &path, Style style = Style::native);
371
372/// Has root directory?
373///
374/// root_directory != ""
375///
376/// @param path Input path.
377/// @result True if the path has a root directory, false otherwise.
378bool has_root_directory(const Twine &path, Style style = Style::native);
379
380/// Has root path?
381///
382/// root_path != ""
383///
384/// @param path Input path.
385/// @result True if the path has a root path, false otherwise.
386bool has_root_path(const Twine &path, Style style = Style::native);
387
388/// Has relative path?
389///
390/// relative_path != ""
391///
392/// @param path Input path.
393/// @result True if the path has a relative path, false otherwise.
394bool has_relative_path(const Twine &path, Style style = Style::native);
395
396/// Has parent path?
397///
398/// parent_path != ""
399///
400/// @param path Input path.
401/// @result True if the path has a parent path, false otherwise.
402bool has_parent_path(const Twine &path, Style style = Style::native);
403
404/// Has filename?
405///
406/// filename != ""
407///
408/// @param path Input path.
409/// @result True if the path has a filename, false otherwise.
410bool has_filename(const Twine &path, Style style = Style::native);
411
412/// Has stem?
413///
414/// stem != ""
415///
416/// @param path Input path.
417/// @result True if the path has a stem, false otherwise.
418bool has_stem(const Twine &path, Style style = Style::native);
419
420/// Has extension?
421///
422/// extension != ""
423///
424/// @param path Input path.
425/// @result True if the path has a extension, false otherwise.
426bool has_extension(const Twine &path, Style style = Style::native);
427
428/// Is path absolute?
429///
430/// @param path Input path.
431/// @result True if the path is absolute, false if it is not.
432bool is_absolute(const Twine &path, Style style = Style::native);
433
434/// Is path relative?
435///
436/// @param path Input path.
437/// @result True if the path is relative, false if it is not.
438bool is_relative(const Twine &path, Style style = Style::native);
439
440/// Remove redundant leading "./" pieces and consecutive separators.
441///
442/// @param path Input path.
443/// @result The cleaned-up \a path.
444StringRef remove_leading_dotslash(StringRef path, Style style = Style::native);
445
446/// In-place remove any './' and optionally '../' components from a path.
447///
448/// @param path processed path
449/// @param remove_dot_dot specify if '../' (except for leading "../") should be
450/// removed
451/// @result True if path was changed
452bool remove_dots(SmallVectorImpl<char> &path, bool remove_dot_dot = false,
453 Style style = Style::native);
454
455#if defined(_WIN32)
456std::error_code widenPath(const Twine &Path8, SmallVectorImpl<wchar_t> &Path16);
457#endif
458
459} // end namespace path
460} // end namespace sys
461} // end namespace llvm
462
463#endif
464