dirent/dirent.h

   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, write to the Free
  16    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  17    02111-1307 USA.  */
  18
  19 /*
  20  *      POSIX Standard: 5.1.2 Directory Operations      <dirent.h>
  21  */
  22
  23 #ifndef _DIRENT_H
  24 #define _DIRENT_H       1
  25
  26 #include <features.h>
  27
  28 __BEGIN_DECLS
  29
  30 #include <bits/types.h>
  31
  32 #ifdef __USE_XOPEN
  33 # ifndef __ino_t_defined
  34 #  ifndef __USE_FILE_OFFSET64
  35 typedef __ino_t ino_t;
  36 #  else
  37 typedef __ino64_t ino_t;
  38 #  endif
  39 #  define __ino_t_defined
  40 # endif
  41 # if defined __USE_LARGEFILE64 && !defined __ino64_t_defined
  42 typedef __ino64_t ino64_t;
  43 #  define __ino64_t_defined
  44 # endif
  45 #endif
  46
  47 /* This file defines `struct dirent'.
  48
  49    It defines the macro `_DIRENT_HAVE_D_NAMLEN' iff there is a `d_namlen'
  50    member that gives the length of `d_name'.
  51
  52    It defines the macro `_DIRENT_HAVE_D_RECLEN' iff there is a `d_reclen'
  53    member that gives the size of the entire directory entry.
  54
  55    It defines the macro `_DIRENT_HAVE_D_OFF' iff there is a `d_off'
  56    member that gives the file offset of the next directory entry.
  57
  58    It defines the macro `_DIRENT_HAVE_D_TYPE' iff there is a `d_type'
  59    member that gives the type of the file.
  60  */
  61
  62 #include <bits/dirent.h>
  63
  64 #if (defined __USE_BSD || defined __USE_MISC) && !defined d_fileno
  65 # define d_ino  d_fileno                 /* Backward compatibility.  */
  66 #endif
  67
  68 /* These macros extract size information from a `struct dirent *'.
  69    They may evaluate their argument multiple times, so it must not
  70    have side effects.  Each of these may involve a relatively costly
  71    call to `strlen' on some systems, so these values should be cached.
  72
  73    _D_EXACT_NAMLEN (DP) returns the length of DP->d_name, not including
  74    its terminating null character.
  75
  76    _D_ALLOC_NAMLEN (DP) returns a size at least (_D_EXACT_NAMLEN (DP) + 1);
  77    that is, the allocation size needed to hold the DP->d_name string.
  78    Use this macro when you don't need the exact length, just an upper bound.
  79    This macro is less likely to require calling `strlen' than _D_EXACT_NAMLEN.
  80    */
  81
  82 #ifdef _DIRENT_HAVE_D_NAMLEN
  83 # define _D_EXACT_NAMLEN(d) ((d)->d_namlen)
  84 # define _D_ALLOC_NAMLEN(d) (_D_EXACT_NAMLEN (d) + 1)
  85 #else
  86 # define _D_EXACT_NAMLEN(d) (strlen ((d)->d_name))
  87 # ifdef _DIRENT_HAVE_D_RECLEN
  88 #  define _D_ALLOC_NAMLEN(d) (((char *) (d) + (d)->d_reclen) - &(d)->d_name[0])
  89 # else
  90 #  define _D_ALLOC_NAMLEN(d) (sizeof (d)->d_name > 1 ? sizeof (d)->d_name : \
  91                               _D_EXACT_NAMLEN (d) + 1)
  92 # endif
  93 #endif
  94
  95
  96 #ifdef __USE_BSD
  97 /* File types for `d_type'.  */
  98 enum
  99   {
 100     DT_UNKNOWN = 0,
 101 # define DT_UNKNOWN     DT_UNKNOWN
 102     DT_FIFO = 1,
 103 # define DT_FIFO        DT_FIFO
 104     DT_CHR = 2,
 105 # define DT_CHR         DT_CHR
 106     DT_DIR = 4,
 107 # define DT_DIR         DT_DIR
 108     DT_BLK = 6,
 109 # define DT_BLK         DT_BLK
 110     DT_REG = 8,
 111 # define DT_REG         DT_REG
 112     DT_LNK = 10,
 113 # define DT_LNK         DT_LNK
 114     DT_SOCK = 12,
 115 # define DT_SOCK        DT_SOCK
 116     DT_WHT = 14
 117 # define DT_WHT         DT_WHT
 118   };
 119
 120 /* Convert between stat structure types and directory types.  */
 121 # define IFTODT(mode)   (((mode) & 0170000) >> 12)
 122 # define DTTOIF(dirtype)        ((dirtype) << 12)
 123 #endif
 124
 125
 126 /* This is the data type of directory stream objects.
 127    The actual structure is opaque to users.  */
 128 typedef struct __dirstream DIR;
 129
 130 /* Open a directory stream on NAME.
 131    Return a DIR stream on the directory, or NULL if it could not be opened.
 132
 133    This function is a possible cancellation point and therefore not
 134    marked with __THROW.  */
 135 extern DIR *opendir (__const char *__name) __nonnull ((1));
 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
 152 /* Read a directory entry from DIRP.  Return a pointer to a `struct
 153    dirent' describing the entry, or NULL for EOF or error.  The
 154    storage returned may be overwritten by a later readdir call on the
 155    same DIR stream.
 156
 157    If the Large File Support API is selected we have to use the
 158    appropriate interface.
 159
 160    This function is a possible cancellation point and therefore not
 161    marked with __THROW.  */
 162 #ifndef __USE_FILE_OFFSET64
 163 extern struct dirent *readdir (DIR *__dirp) __nonnull ((1));
 164 #else
 165 # ifdef __REDIRECT
 166 extern struct dirent *__REDIRECT (readdir, (DIR *__dirp), readdir64)
 167      __nonnull ((1));
 168 # else
 169 #  define readdir readdir64
 170 # endif
 171 #endif
 172
 173 #ifdef __USE_LARGEFILE64
 174 extern struct dirent64 *readdir64 (DIR *__dirp) __nonnull ((1));
 175 #endif
 176
 177 #if defined __USE_POSIX || defined __USE_MISC
 178 /* Reentrant version of `readdir'.  Return in RESULT a pointer to the
 179    next entry.
 180
 181    This function is a possible cancellation point and therefore not
 182    marked with __THROW.  */
 183 # ifndef __USE_FILE_OFFSET64
 184 extern int readdir_r (DIR *__restrict __dirp,
 185                       struct dirent *__restrict __entry,
 186                       struct dirent **__restrict __result)
 187      __nonnull ((1, 2, 3));
 188 # else
 189 #  ifdef __REDIRECT
 190 extern int __REDIRECT (readdir_r,
 191                        (DIR *__restrict __dirp,
 192                         struct dirent *__restrict __entry,
 193                         struct dirent **__restrict __result),
 194                        readdir64_r) __nonnull ((1, 2, 3));
 195 #  else
 196 #   define readdir_r readdir64_r
 197 #  endif
 198 # endif
 199
 200 # ifdef __USE_LARGEFILE64
 201 extern int readdir64_r (DIR *__restrict __dirp,
 202                         struct dirent64 *__restrict __entry,
 203                         struct dirent64 **__restrict __result)
 204      __nonnull ((1, 2, 3));
 205 # endif
 206 #endif  /* POSIX or misc */
 207
 208 /* Rewind DIRP to the beginning of the directory.  */
 209 extern void rewinddir (DIR *__dirp) __THROW __nonnull ((1));
 210
 211 #if defined __USE_BSD || defined __USE_MISC || defined __USE_XOPEN
 212 # include <bits/types.h>
 213
 214 /* Seek to position POS on DIRP.  */
 215 extern void seekdir (DIR *__dirp, long int __pos) __THROW __nonnull ((1));
 216
 217 /* Return the current position of DIRP.  */
 218 extern long int telldir (DIR *__dirp) __THROW __nonnull ((1));
 219 #endif
 220
 221 #if defined __USE_BSD || defined __USE_MISC || defined __USE_XOPEN2K8
 222
 223 /* Return the file descriptor used by DIRP.  */
 224 extern int dirfd (DIR *__dirp) __THROW __nonnull ((1));
 225
 226 # if defined __OPTIMIZE__ && defined _DIR_dirfd
 227 #  define dirfd(dirp)   _DIR_dirfd (dirp)
 228 # endif
 229
 230 # if defined __USE_BSD || defined __USE_MISC
 231 #  ifndef MAXNAMLEN
 232 /* Get the definitions of the POSIX.1 limits.  */
 233 #  include <bits/posix1_lim.h>
 234
 235 /* `MAXNAMLEN' is the BSD name for what POSIX calls `NAME_MAX'.  */
 236 #   ifdef NAME_MAX
 237 #    define MAXNAMLEN   NAME_MAX
 238 #   else
 239 #    define MAXNAMLEN   255
 240 #   endif
 241 #  endif
 242 # endif
 243
 244 # define __need_size_t
 245 # include <stddef.h>
 246
 247 /* Scan the directory DIR, calling SELECTOR on each directory entry.
 248    Entries for which SELECT returns nonzero are individually malloc'd,
 249    sorted using qsort with CMP, and collected in a malloc'd array in
 250    *NAMELIST.  Returns the number of entries selected, or -1 on error.  */
 251 # ifndef __USE_FILE_OFFSET64
 252 extern int scandir (__const char *__restrict __dir,
 253                     struct dirent ***__restrict __namelist,
 254                     int (*__selector) (__const struct dirent *),
 255                     int (*__cmp) (__const struct dirent **,
 256                                   __const struct dirent **))
 257      __nonnull ((1, 2));
 258 # else
 259 #  ifdef __REDIRECT
 260 extern int __REDIRECT (scandir,
 261                        (__const char *__restrict __dir,
 262                         struct dirent ***__restrict __namelist,
 263                         int (*__selector) (__const struct dirent *),
 264                         int (*__cmp) (__const struct dirent **,
 265                                       __const struct dirent **)),
 266                        scandir64) __nonnull ((1, 2));
 267 #  else
 268 #   define scandir scandir64
 269 #  endif
 270 # endif
 271
 272 # if defined __USE_GNU && defined __USE_LARGEFILE64
 273 /* This function is like `scandir' but it uses the 64bit dirent structure.
 274    Please note that the CMP function must now work with struct dirent64 **.  */
 275 extern int scandir64 (__const char *__restrict __dir,
 276                       struct dirent64 ***__restrict __namelist,
 277                       int (*__selector) (__const struct dirent64 *),
 278                       int (*__cmp) (__const struct dirent64 **,
 279                                     __const struct dirent64 **))
 280      __nonnull ((1, 2));
 281 # endif
 282
 283 /* Function to compare two `struct dirent's alphabetically.  */
 284 # ifndef __USE_FILE_OFFSET64
 285 extern int alphasort (__const struct dirent **__e1,
 286                       __const struct dirent **__e2)
 287      __THROW __attribute_pure__ __nonnull ((1, 2));
 288 # else
 289 #  ifdef __REDIRECT
 290 extern int __REDIRECT_NTH (alphasort,
 291                            (__const struct dirent **__e1,
 292                             __const struct dirent **__e2),
 293                            alphasort64) __attribute_pure__ __nonnull ((1, 2));
 294 #  else
 295 #   define alphasort alphasort64
 296 #  endif
 297 # endif
 298
 299 # if defined __USE_GNU && defined __USE_LARGEFILE64
 300 extern int alphasort64 (__const struct dirent64 **__e1,
 301                         __const struct dirent64 **__e2)
 302      __THROW __attribute_pure__ __nonnull ((1, 2));
 303 # endif
 304 #endif /* Use BSD or misc or XPG7.  */
 305
 306
 307 #if defined __USE_BSD || defined __USE_MISC
 308 /* Read directory entries from FD into BUF, reading at most NBYTES.
 309    Reading starts at offset *BASEP, and *BASEP is updated with the new
 310    position after reading.  Returns the number of bytes read; zero when at
 311    end of directory; or -1 for errors.  */
 312 # ifndef __USE_FILE_OFFSET64
 313 extern __ssize_t getdirentries (int __fd, char *__restrict __buf,
 314                                 size_t __nbytes,
 315                                 __off_t *__restrict __basep)
 316      __THROW __nonnull ((2, 4));
 317 # else
 318 #  ifdef __REDIRECT
 319 extern __ssize_t __REDIRECT_NTH (getdirentries,
 320                                  (int __fd, char *__restrict __buf,
 321                                   size_t __nbytes,
 322                                   __off64_t *__restrict __basep),
 323                                  getdirentries64) __nonnull ((2, 4));
 324 #  else
 325 #   define getdirentries getdirentries64
 326 #  endif
 327 # endif
 328
 329 # ifdef __USE_LARGEFILE64
 330 extern __ssize_t getdirentries64 (int __fd, char *__restrict __buf,
 331                                   size_t __nbytes,
 332                                   __off64_t *__restrict __basep)
 333      __THROW __nonnull ((2, 4));
 334 # endif
 335 #endif /* Use BSD or misc.  */
 336
 337 #ifdef __USE_GNU
 338 /* Function to compare two `struct dirent's by name & version.  */
 339 # ifndef __USE_FILE_OFFSET64
 340 extern int versionsort (__const struct dirent **__e1,
 341                         __const struct dirent **__e2)
 342      __THROW __attribute_pure__ __nonnull ((1, 2));
 343 # else
 344 #  ifdef __REDIRECT
 345 extern int __REDIRECT_NTH (versionsort,
 346                            (__const struct dirent **__e1,
 347                             __const struct dirent **__e2),
 348                            versionsort64)
 349      __attribute_pure__ __nonnull ((1, 2));
 350 #  else
 351 #   define versionsort versionsort64
 352 #  endif
 353 # endif
 354
 355 # ifdef __USE_LARGEFILE64
 356 extern int versionsort64 (__const struct dirent64 **__e1,
 357                           __const struct dirent64 **__e2)
 358      __THROW __attribute_pure__ __nonnull ((1, 2));
 359 # endif
 360 #endif /* Use GNU.  */
 361
 362 __END_DECLS
 363
 364 #endif /* dirent.h  */