1 /* Copyright (C) 1991-2000,2003-2005,2009,2010 Free Software Foundation, Inc.
2    This file is part of the GNU C Library.
3 
4    The GNU C Library is free software; you can redistribute it and/or
5    modify it under the terms of the GNU Lesser General Public
6    License as published by the Free Software Foundation; either
7    version 2.1 of the License, or (at your option) any later version.
8 
9    The GNU C Library is distributed in the hope that it will be useful,
10    but WITHOUT ANY WARRANTY; without even the implied warranty of
11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12    Lesser General Public License for more details.
13 
14    You should have received a copy of the GNU Lesser General Public
15    License along with the GNU C Library; if not, see
16    <http://www.gnu.org/licenses/>.  */
17 
18 /*
19  *	POSIX Standard: 5.1.2 Directory Operations	<dirent.h>
20  */
21 
22 #ifndef	_DIRENT_H
23 #define	_DIRENT_H	1
24 
25 #include <features.h>
26 
27 __BEGIN_DECLS
28 
29 #include <bits/types.h>
30 
31 #ifdef __USE_XOPEN
32 # ifndef __ino_t_defined
33 #  ifndef __USE_FILE_OFFSET64
34 typedef __ino_t ino_t;
35 #  else
36 typedef __ino64_t ino_t;
37 #  endif
38 #  define __ino_t_defined
39 # endif
40 # if defined __USE_LARGEFILE64 && !defined __ino64_t_defined
41 typedef __ino64_t ino64_t;
42 #  define __ino64_t_defined
43 # endif
44 #endif
45 
46 /* This file defines `struct dirent'.
47 
48    It defines the macro `_DIRENT_HAVE_D_NAMLEN' iff there is a `d_namlen'
49    member that gives the length of `d_name'.
50 
51    It defines the macro `_DIRENT_HAVE_D_RECLEN' iff there is a `d_reclen'
52    member that gives the size of the entire directory entry.
53 
54    It defines the macro `_DIRENT_HAVE_D_OFF' iff there is a `d_off'
55    member that gives the file offset of the next directory entry.
56 
57    It defines the macro `_DIRENT_HAVE_D_TYPE' iff there is a `d_type'
58    member that gives the type of the file.
59  */
60 
61 #include <bits/dirent.h>
62 
63 #if (defined __USE_BSD || defined __USE_MISC) && !defined d_fileno
64 # define d_ino	d_fileno		 /* Backward compatibility.  */
65 #endif
66 
67 /* These macros extract size information from a `struct dirent *'.
68    They may evaluate their argument multiple times, so it must not
69    have side effects.  Each of these may involve a relatively costly
70    call to `strlen' on some systems, so these values should be cached.
71 
72    _D_EXACT_NAMLEN (DP)	returns the length of DP->d_name, not including
73    its terminating null character.
74 
75    _D_ALLOC_NAMLEN (DP)	returns a size at least (_D_EXACT_NAMLEN (DP) + 1);
76    that is, the allocation size needed to hold the DP->d_name string.
77    Use this macro when you don't need the exact length, just an upper bound.
78    This macro is less likely to require calling `strlen' than _D_EXACT_NAMLEN.
79    */
80 
81 #ifdef _DIRENT_HAVE_D_NAMLEN
82 # define _D_EXACT_NAMLEN(d) ((d)->d_namlen)
83 # define _D_ALLOC_NAMLEN(d) (_D_EXACT_NAMLEN (d) + 1)
84 #else
85 # define _D_EXACT_NAMLEN(d) (strlen ((d)->d_name))
86 # ifdef _DIRENT_HAVE_D_RECLEN
87 #  define _D_ALLOC_NAMLEN(d) (((char *) (d) + (d)->d_reclen) - &(d)->d_name[0])
88 # else
89 #  define _D_ALLOC_NAMLEN(d) (sizeof (d)->d_name > 1 ? sizeof (d)->d_name : \
90 			      _D_EXACT_NAMLEN (d) + 1)
91 # endif
92 #endif
93 
94 
95 #ifdef __USE_BSD
96 /* File types for `d_type'.  */
97 enum
98   {
99     DT_UNKNOWN = 0,
100 # define DT_UNKNOWN	DT_UNKNOWN
101     DT_FIFO = 1,
102 # define DT_FIFO	DT_FIFO
103     DT_CHR = 2,
104 # define DT_CHR		DT_CHR
105     DT_DIR = 4,
106 # define DT_DIR		DT_DIR
107     DT_BLK = 6,
108 # define DT_BLK		DT_BLK
109     DT_REG = 8,
110 # define DT_REG		DT_REG
111     DT_LNK = 10,
112 # define DT_LNK		DT_LNK
113     DT_SOCK = 12,
114 # define DT_SOCK	DT_SOCK
115     DT_WHT = 14
116 # define DT_WHT		DT_WHT
117   };
118 
119 /* Convert between stat structure types and directory types.  */
120 # define IFTODT(mode)	(((mode) & 0170000) >> 12)
121 # define DTTOIF(dirtype)	((dirtype) << 12)
122 #endif
123 
124 
125 /* This is the data type of directory stream objects.
126    The actual structure is opaque to users.  */
127 typedef struct __dirstream DIR;
128 
129 /* Open a directory stream on NAME.
130    Return a DIR stream on the directory, or NULL if it could not be opened.
131 
132    This function is a possible cancellation point and therefore not
133    marked with __THROW.  */
134 extern DIR *opendir (const char *__name) __nonnull ((1));
135 libc_hidden_proto(opendir)
136 
137 #ifdef __USE_XOPEN2K8
138 /* Same as opendir, but open the stream on the file descriptor FD.
139 
140    This function is a possible cancellation point and therefore not
141    marked with __THROW.  */
142 extern DIR *fdopendir (int __fd);
143 #endif
144 
145 /* Close the directory stream DIRP.
146    Return 0 if successful, -1 if not.
147 
148    This function is a possible cancellation point and therefore not
149    marked with __THROW.  */
150 extern int closedir (DIR *__dirp) __nonnull ((1));
151 libc_hidden_proto(closedir)
152 
153 /* Read a directory entry from DIRP.  Return a pointer to a `struct
154    dirent' describing the entry, or NULL for EOF or error.  The
155    storage returned may be overwritten by a later readdir call on the
156    same DIR stream.
157 
158    If the Large File Support API is selected we have to use the
159    appropriate interface.
160 
161    This function is a possible cancellation point and therefore not
162    marked with __THROW.  */
163 #ifndef __USE_FILE_OFFSET64
164 extern struct dirent *readdir (DIR *__dirp) __nonnull ((1));
165 libc_hidden_proto(readdir)
166 #else
167 # ifdef __REDIRECT
168 extern struct dirent *__REDIRECT (readdir, (DIR *__dirp), readdir64)
169      __nonnull ((1));
170 # else
171 #  define readdir readdir64
172 # endif
173 #endif
174 
175 #ifdef __USE_LARGEFILE64
176 extern struct dirent64 *readdir64 (DIR *__dirp) __nonnull ((1));
177 libc_hidden_proto(readdir64)
178 #endif
179 
180 #if defined __USE_POSIX || defined __USE_MISC
181 /* Reentrant version of `readdir'.  Return in RESULT a pointer to the
182    next entry.
183 
184    This function is a possible cancellation point and therefore not
185    marked with __THROW.  */
186 # ifndef __USE_FILE_OFFSET64
187 extern int readdir_r (DIR *__restrict __dirp,
188 		      struct dirent *__restrict __entry,
189 		      struct dirent **__restrict __result)
190      __nonnull ((1, 2, 3));
191 libc_hidden_proto(readdir_r)
192 # else
193 #  ifdef __REDIRECT
194 extern int __REDIRECT (readdir_r,
195 		       (DIR *__restrict __dirp,
196 			struct dirent *__restrict __entry,
197 			struct dirent **__restrict __result),
198 		       readdir64_r) __nonnull ((1, 2, 3));
199 #  else
200 #   define readdir_r readdir64_r
201 #  endif
202 # endif
203 
204 # ifdef __USE_LARGEFILE64
205 extern int readdir64_r (DIR *__restrict __dirp,
206 			struct dirent64 *__restrict __entry,
207 			struct dirent64 **__restrict __result)
208      __nonnull ((1, 2, 3));
209 libc_hidden_proto(readdir64_r)
210 # endif
211 #endif	/* POSIX or misc */
212 
213 /* Rewind DIRP to the beginning of the directory.  */
214 extern void rewinddir (DIR *__dirp) __THROW __nonnull ((1));
215 
216 #if defined __USE_BSD || defined __USE_MISC || defined __USE_XOPEN
217 # include <bits/types.h>
218 
219 /* Seek to position POS on DIRP.  */
220 extern void seekdir (DIR *__dirp, long int __pos) __THROW __nonnull ((1));
221 
222 /* Return the current position of DIRP.  */
223 extern long int telldir (DIR *__dirp) __THROW __nonnull ((1));
224 #endif
225 
226 #if defined __USE_BSD || defined __USE_MISC || defined __USE_XOPEN2K8
227 
228 /* Return the file descriptor used by DIRP.  */
229 extern int dirfd (DIR *__dirp) __THROW __nonnull ((1));
230 libc_hidden_proto(dirfd)
231 
232 # if 0 /* defined __OPTIMIZE__ && defined _DIR_dirfd */
233 #  define dirfd(dirp)	_DIR_dirfd (dirp)
234 # endif
235 
236 # if defined __USE_BSD || defined __USE_MISC
237 #  ifndef MAXNAMLEN
238 /* Get the definitions of the POSIX.1 limits.  */
239 #  include <bits/posix1_lim.h>
240 
241 /* `MAXNAMLEN' is the BSD name for what POSIX calls `NAME_MAX'.  */
242 #   ifdef NAME_MAX
243 #    define MAXNAMLEN	NAME_MAX
244 #   else
245 #    define MAXNAMLEN	255
246 #   endif
247 #  endif
248 # endif
249 
250 # define __need_size_t
251 # include <stddef.h>
252 
253 /* Scan the directory DIR, calling SELECTOR on each directory entry.
254    Entries for which SELECT returns nonzero are individually malloc'd,
255    sorted using qsort with CMP, and collected in a malloc'd array in
256    *NAMELIST.  Returns the number of entries selected, or -1 on error.  */
257 # ifndef __USE_FILE_OFFSET64
258 extern int scandir (const char *__restrict __dir,
259 		    struct dirent ***__restrict __namelist,
260 		    int (*__selector) (const struct dirent *),
261 		    int (*__cmp) (const struct dirent **,
262 				  const struct dirent **))
263      __nonnull ((1, 2));
264 # else
265 #  ifdef __REDIRECT
266 extern int __REDIRECT (scandir,
267 		       (const char *__restrict __dir,
268 			struct dirent ***__restrict __namelist,
269 			int (*__selector) (const struct dirent *),
270 			int (*__cmp) (const struct dirent **,
271 				      const struct dirent **)),
272 		       scandir64) __nonnull ((1, 2));
273 #  else
274 #   define scandir scandir64
275 #  endif
276 # endif
277 
278 # if defined __USE_GNU && defined __USE_LARGEFILE64
279 /* This function is like `scandir' but it uses the 64bit dirent structure.
280    Please note that the CMP function must now work with struct dirent64 **.  */
281 extern int scandir64 (const char *__restrict __dir,
282 		      struct dirent64 ***__restrict __namelist,
283 		      int (*__selector) (const struct dirent64 *),
284 		      int (*__cmp) (const struct dirent64 **,
285 				    const struct dirent64 **))
286      __nonnull ((1, 2));
287 # endif
288 
289 /* Function to compare two `struct dirent's alphabetically.  */
290 # ifndef __USE_FILE_OFFSET64
291 extern int alphasort (const struct dirent **__e1,
292 		      const struct dirent **__e2)
293      __THROW __attribute_pure__ __nonnull ((1, 2));
294 # else
295 #  ifdef __REDIRECT
296 extern int __REDIRECT_NTH (alphasort,
297 			   (const struct dirent **__e1,
298 			    const struct dirent **__e2),
299 			   alphasort64) __attribute_pure__ __nonnull ((1, 2));
300 #  else
301 #   define alphasort alphasort64
302 #  endif
303 # endif
304 
305 # if defined __USE_GNU && defined __USE_LARGEFILE64
306 extern int alphasort64 (const struct dirent64 **__e1,
307 			const struct dirent64 **__e2)
308      __THROW __attribute_pure__ __nonnull ((1, 2));
309 # endif
310 #endif /* Use BSD or misc or XPG7.  */
311 
312 
313 #if 0 /* defined __USE_BSD || defined __USE_MISC */
314 /* Read directory entries from FD into BUF, reading at most NBYTES.
315    Reading starts at offset *BASEP, and *BASEP is updated with the new
316    position after reading.  Returns the number of bytes read; zero when at
317    end of directory; or -1 for errors.  */
318 # ifndef __USE_FILE_OFFSET64
319 extern __ssize_t getdirentries (int __fd, char *__restrict __buf,
320 				size_t __nbytes,
321 				__off_t *__restrict __basep)
322      __THROW __nonnull ((2, 4));
323 # else
324 #  ifdef __REDIRECT
325 extern __ssize_t __REDIRECT_NTH (getdirentries,
326 				 (int __fd, char *__restrict __buf,
327 				  size_t __nbytes,
328 				  __off64_t *__restrict __basep),
329 				 getdirentries64) __nonnull ((2, 4));
330 #  else
331 #   define getdirentries getdirentries64
332 #  endif
333 # endif
334 
335 # ifdef __USE_LARGEFILE64
336 extern __ssize_t getdirentries64 (int __fd, char *__restrict __buf,
337 				  size_t __nbytes,
338 				  __off64_t *__restrict __basep)
339      __THROW __nonnull ((2, 4));
340 # endif
341 #endif /* Use BSD or misc.  */
342 
343 #ifdef __USE_GNU
344 /* Function to compare two `struct dirent's by name & version.  */
345 # ifndef __USE_FILE_OFFSET64
346 extern int versionsort (const struct dirent **__e1,
347 			const struct dirent **__e2)
348      __THROW __attribute_pure__ __nonnull ((1, 2));
349 # else
350 #  ifdef __REDIRECT
351 extern int __REDIRECT_NTH (versionsort,
352 			   (const struct dirent **__e1,
353 			    const struct dirent **__e2),
354 			   versionsort64)
355      __attribute_pure__ __nonnull ((1, 2));
356 #  else
357 #   define versionsort versionsort64
358 #  endif
359 # endif
360 
361 # ifdef __USE_LARGEFILE64
362 extern int versionsort64 (const struct dirent64 **__e1,
363 			  const struct dirent64 **__e2)
364      __THROW __attribute_pure__ __nonnull ((1, 2));
365 # endif
366 #endif /* Use GNU.  */
367 
368 __END_DECLS
369 
370 #ifdef _LIBC
371 extern __ssize_t __getdents(int fd, char *buf, size_t count) attribute_hidden;
372 extern __ssize_t __getdents64 (int fd, char *buf, size_t count) attribute_hidden;
373 #endif
374 
375 #endif /* dirent.h  */
376