1 /*
2  * Copyright (C) 2008 The Android Open Source Project
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  *  * Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  *  * Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in
12  *    the documentation and/or other materials provided with the
13  *    distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19  * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #pragma once
30 
31 /**
32  * @file dirent.h
33  * @brief Directory entry iteration.
34  */
35 
36 #include <stdint.h>
37 #include <sys/cdefs.h>
38 #include <sys/types.h>
39 
40 __BEGIN_DECLS
41 
42 /** d_type value when the type is not known. */
43 #define DT_UNKNOWN 0
44 /** d_type value for a FIFO. */
45 #define DT_FIFO 1
46 /** d_type value for a character device. */
47 #define DT_CHR 2
48 /** d_type value for a directory. */
49 #define DT_DIR 4
50 /** d_type value for a block device. */
51 #define DT_BLK 6
52 /** d_type value for a regular file. */
53 #define DT_REG 8
54 /** d_type value for a symbolic link. */
55 #define DT_LNK 10
56 /** d_type value for a socket. */
57 #define DT_SOCK 12
58 #define DT_WHT 14
59 
60 #if defined(__LP64__)
61 #define __DIRENT64_INO_T ino_t
62 #else
63 #define __DIRENT64_INO_T uint64_t /* Historical accident. */
64 #endif
65 
66 #define __DIRENT64_BODY \
67     __DIRENT64_INO_T d_ino; \
68     off64_t d_off; \
69     unsigned short d_reclen; \
70     unsigned char d_type; \
71     char d_name[256]; \
72 
73 /** The structure returned by readdir(). Identical to dirent64 on Android. */
74 struct dirent { __DIRENT64_BODY };
75 /** The structure returned by readdir64(). Identical to dirent on Android. */
76 struct dirent64 { __DIRENT64_BODY };
77 
78 #undef __DIRENT64_BODY
79 #undef __DIRENT64_INO_T
80 
81 /* glibc compatibility. */
82 #undef _DIRENT_HAVE_D_NAMLEN /* Linux doesn't have a d_namlen field. */
83 #define _DIRENT_HAVE_D_RECLEN
84 #define _DIRENT_HAVE_D_OFF
85 #define _DIRENT_HAVE_D_TYPE
86 
87 #define d_fileno d_ino
88 
89 /** The structure returned by opendir()/fopendir(). */
90 typedef struct DIR DIR;
91 
92 /**
93  * [opendir(3)](http://man7.org/linux/man-pages/man3/opendir.3.html)
94  * opens a directory stream for the directory at `__path`.
95  *
96  * Returns null and sets `errno` on failure.
97  */
98 DIR* opendir(const char* __path);
99 
100 /**
101  * [fopendir(3)](http://man7.org/linux/man-pages/man3/opendir.3.html)
102  * opens a directory stream for the directory at `__dir_fd`.
103  *
104  * Returns null and sets `errno` on failure.
105  */
106 DIR* fdopendir(int __dir_fd);
107 
108 /**
109  * [readdir(3)](http://man7.org/linux/man-pages/man3/readdir.3.html)
110  * returns the next directory entry in the given directory.
111  *
112  * Returns a pointer to a directory entry on success,
113  * or returns null and leaves `errno` unchanged at the end of the directory,
114  * or returns null and sets `errno` on failure.
115  */
116 struct dirent* readdir(DIR* __dir);
117 
118 /**
119  * [readdir64(3)](http://man7.org/linux/man-pages/man3/readdir.3.html)
120  * returns the next directory entry in the given directory.
121  *
122  * Returns a pointer to a directory entry on success,
123  * or returns null and leaves `errno` unchanged at the end of the directory,
124  * or returns null and sets `errno` on failure.
125  */
126 
127 #if __ANDROID_API__ >= 21
128 struct dirent64* readdir64(DIR* __dir) __INTRODUCED_IN(21);
129 #endif /* __ANDROID_API__ >= 21 */
130 
131 
132 int readdir_r(DIR* __dir, struct dirent* __entry, struct dirent** __buffer) __attribute__((__deprecated__("readdir_r is deprecated; use readdir instead")));
133 
134 #if __ANDROID_API__ >= 21
135 int readdir64_r(DIR* __dir, struct dirent64* __entry, struct dirent64** __buffer) __INTRODUCED_IN(21) __attribute__((__deprecated__("readdir64_r is deprecated; use readdir64 instead")));
136 #endif /* __ANDROID_API__ >= 21 */
137 
138 
139 /**
140  * [closedir(3)](http://man7.org/linux/man-pages/man3/closedir.3.html)
141  * closes a directory stream.
142  *
143  * Returns 0 on success and returns -1 and sets `errno` on failure.
144  */
145 int closedir(DIR* __dir);
146 
147 /**
148  * [rewinddir(3)](http://man7.org/linux/man-pages/man3/rewinddir.3.html)
149  * rewinds a directory stream to the first entry.
150  */
151 void rewinddir(DIR* __dir);
152 
153 /**
154  * [seekdir(3)](http://man7.org/linux/man-pages/man3/seekdir.3.html)
155  * seeks a directory stream to the given entry, which must be a value returned
156  * by telldir().
157  *
158  * Available since API level 23.
159  */
160 
161 #if __ANDROID_API__ >= 23
162 void seekdir(DIR* __dir, long __location) __INTRODUCED_IN(23);
163 
164 /**
165  * [telldir(3)](http://man7.org/linux/man-pages/man3/telldir.3.html)
166  * returns a value representing the current position in the directory
167  * for use with seekdir().
168  *
169  * Returns the current position on success and returns -1 and sets `errno` on failure.
170  *
171  * Available since API level 23.
172  */
173 long telldir(DIR* __dir) __INTRODUCED_IN(23);
174 #endif /* __ANDROID_API__ >= 23 */
175 
176 
177 /**
178  * [dirfd(3)](http://man7.org/linux/man-pages/man3/dirfd.3.html)
179  * returns the file descriptor backing the given directory stream.
180  *
181  * Returns a file descriptor on success and returns -1 and sets `errno` on failure.
182  */
183 int dirfd(DIR* __dir);
184 
185 /**
186  * [alphasort](http://man7.org/linux/man-pages/man3/alphasort.3.html) is a
187  * comparator for use with scandir() that uses strcoll().
188  */
189 int alphasort(const struct dirent** __lhs, const struct dirent** __rhs);
190 
191 /**
192  * [alphasort64](http://man7.org/linux/man-pages/man3/alphasort.3.html) is a
193  * comparator for use with scandir64() that uses strcmp().
194  *
195  * Available since API level 21.
196  */
197 
198 #if __ANDROID_API__ >= 21
199 int alphasort64(const struct dirent64** __lhs, const struct dirent64** __rhs) __INTRODUCED_IN(21);
200 #endif /* __ANDROID_API__ >= 21 */
201 
202 
203 /**
204  * [scandir(3)](http://man7.org/linux/man-pages/man3/scandir.3.html)
205  * scans all the directory `__path`, filtering entries with `__filter` and
206  * sorting them with qsort() using the given `__comparator`, and storing them
207  * into `__name_list`. Passing NULL as the filter accepts all entries.
208  *
209  * Returns the number of entries returned in the list on success,
210  * and returns -1 and sets `errno` on failure.
211  */
212 int scandir(const char* __path, struct dirent*** __name_list, int (*__filter)(const struct dirent*), int (*__comparator)(const struct dirent**, const struct dirent**));
213 
214 /**
215  * [scandir64(3)](http://man7.org/linux/man-pages/man3/scandir.3.html)
216  * scans all the directory `__path`, filtering entries with `__filter` and
217  * sorting them with qsort() using the given `__comparator`, and storing them
218  * into `__name_list`. Passing NULL as the filter accepts all entries.
219  *
220  * Returns the number of entries returned in the list on success,
221  * and returns -1 and sets `errno` on failure.
222  *
223  * Available since API level 21.
224  */
225 
226 #if __ANDROID_API__ >= 21
227 int scandir64(const char* __path, struct dirent64*** __name_list, int (*__filter)(const struct dirent64*), int (*__comparator)(const struct dirent64**, const struct dirent64**)) __INTRODUCED_IN(21);
228 #endif /* __ANDROID_API__ >= 21 */
229 
230 
231 #if defined(__USE_GNU)
232 
233 /**
234  * [scandirat64(3)](http://man7.org/linux/man-pages/man3/scandirat.3.html)
235  * scans all the directory referenced by the pair of `__dir_fd` and `__path`,
236  * filtering entries with `__filter` and sorting them with qsort() using the
237  * given `__comparator`, and storing them into `__name_list`. Passing NULL as
238  * the filter accepts all entries.
239  *
240  * Returns the number of entries returned in the list on success,
241  * and returns -1 and sets `errno` on failure.
242  *
243  * Available since API level 24.
244  */
245 
246 #if __ANDROID_API__ >= 24
247 int scandirat64(int __dir_fd, const char* __path, struct dirent64*** __name_list, int (*__filter)(const struct dirent64*), int (*__comparator)(const struct dirent64**, const struct dirent64**)) __INTRODUCED_IN(24);
248 
249 /**
250  * [scandirat(3)](http://man7.org/linux/man-pages/man3/scandirat.3.html)
251  * scans all the directory referenced by the pair of `__dir_fd` and `__path`,
252  * filtering entries with `__filter` and sorting them with qsort() using the
253  * given `__comparator`, and storing them into `__name_list`. Passing NULL as
254  * the filter accepts all entries.
255  *
256  * Returns the number of entries returned in the list on success,
257  * and returns -1 and sets `errno` on failure.
258  *
259  * Available since API level 24.
260  */
261 int scandirat(int __dir_fd, const char* __path, struct dirent*** __name_list, int (*__filter)(const struct dirent*), int (*__comparator)(const struct dirent**, const struct dirent**)) __INTRODUCED_IN(24);
262 #endif /* __ANDROID_API__ >= 24 */
263 
264 
265 #endif
266 
267 __END_DECLS
268