dirent/dirent.h

   1 /* Copyright (C) 1991-2000, 2003, 2004 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 /* Close the directory stream DIRP.
 138    Return 0 if successful, -1 if not.
 139
 140    This function is a possible cancellation point and therefore not
 141    marked with __THROW.  */
 142 extern int closedir (DIR *__dirp) __nonnull ((1));
 143
 144 /* Read a directory entry from DIRP.  Return a pointer to a `struct
 145    dirent' describing the entry, or NULL for EOF or error.  The
 146    storage returned may be overwritten by a later readdir call on the
 147    same DIR stream.
 148
 149    If the Large File Support API is selected we have to use the
 150    appropriate interface.
 151
 152    This function is a possible cancellation point and therefore not
 153    marked with __THROW.  */
 154 #ifndef __USE_FILE_OFFSET64
 155 extern struct dirent *readdir (DIR *__dirp) __nonnull ((1));
 156 #else
 157 # ifdef __REDIRECT
 158 extern struct dirent *__REDIRECT (readdir, (DIR *__dirp), readdir64)
 159      __nonnull ((1));
 160 # else
 161 #  define readdir readdir64
 162 # endif
 163 #endif
 164
 165 #ifdef __USE_LARGEFILE64
 166 extern struct dirent64 *readdir64 (DIR *__dirp) __nonnull ((1));
 167 #endif
 168
 169 #if defined __USE_POSIX || defined __USE_MISC
 170 /* Reentrant version of `readdir'.  Return in RESULT a pointer to the
 171    next entry.
 172
 173    This function is a possible cancellation point and therefore not
 174    marked with __THROW.  */
 175 # ifndef __USE_FILE_OFFSET64
 176 extern int readdir_r (DIR *__restrict __dirp,
 177                       struct dirent *__restrict __entry,
 178                       struct dirent **__restrict __result)
 179      __nonnull ((1, 2, 3));
 180 # else
 181 #  ifdef __REDIRECT
 182 extern int __REDIRECT (readdir_r,
 183                        (DIR *__restrict __dirp,
 184                         struct dirent *__restrict __entry,
 185                         struct dirent **__restrict __result),
 186                        readdir64_r) __nonnull ((1, 2, 3));
 187 #  else
 188 #   define readdir_r readdir64_r
 189 #  endif
 190 # endif
 191
 192 # ifdef __USE_LARGEFILE64
 193 extern int readdir64_r (DIR *__restrict __dirp,
 194                         struct dirent64 *__restrict __entry,
 195                         struct dirent64 **__restrict __result)
 196      __nonnull ((1, 2, 3));
 197 # endif
 198 #endif  /* POSIX or misc */
 199
 200 /* Rewind DIRP to the beginning of the directory.  */
 201 extern void rewinddir (DIR *__dirp) __THROW __nonnull ((1));
 202
 203 #if defined __USE_BSD || defined __USE_MISC || defined __USE_XOPEN
 204 # include <bits/types.h>
 205
 206 /* Seek to position POS on DIRP.  */
 207 extern void seekdir (DIR *__dirp, long int __pos) __THROW __nonnull ((1));
 208
 209 /* Return the current position of DIRP.  */
 210 extern long int telldir (DIR *__dirp) __THROW __nonnull ((1));
 211 #endif
 212
 213 #if defined __USE_BSD || defined __USE_MISC
 214
 215 /* Return the file descriptor used by DIRP.  */
 216 extern int dirfd (DIR *__dirp) __THROW __nonnull ((1));
 217
 218 # if defined __OPTIMIZE__ && defined _DIR_dirfd
 219 #  define dirfd(dirp)   _DIR_dirfd (dirp)
 220 # endif
 221
 222 # ifndef MAXNAMLEN
 223 /* Get the definitions of the POSIX.1 limits.  */
 224 #  include <bits/posix1_lim.h>
 225
 226 /* `MAXNAMLEN' is the BSD name for what POSIX calls `NAME_MAX'.  */
 227 #  ifdef NAME_MAX
 228 #   define MAXNAMLEN    NAME_MAX
 229 #  else
 230 #   define MAXNAMLEN    255
 231 #  endif
 232 # endif
 233
 234 # define __need_size_t
 235 # include <stddef.h>
 236
 237 /* Scan the directory DIR, calling SELECTOR on each directory entry.
 238    Entries for which SELECT returns nonzero are individually malloc'd,
 239    sorted using qsort with CMP, and collected in a malloc'd array in
 240    *NAMELIST.  Returns the number of entries selected, or -1 on error.  */
 241 # ifndef __USE_FILE_OFFSET64
 242 extern int scandir (__const char *__restrict __dir,
 243                     struct dirent ***__restrict __namelist,
 244                     int (*__selector) (__const struct dirent *),
 245                     int (*__cmp) (__const void *, __const void *))
 246      __nonnull ((1, 2));
 247 # else
 248 #  ifdef __REDIRECT
 249 extern int __REDIRECT (scandir,
 250                        (__const char *__restrict __dir,
 251                         struct dirent ***__restrict __namelist,
 252                         int (*__selector) (__const struct dirent *),
 253                         int (*__cmp) (__const void *, __const void *)),
 254                        scandir64) __nonnull ((1, 2));
 255 #  else
 256 #   define scandir scandir64
 257 #  endif
 258 # endif
 259
 260 # if defined __USE_GNU && defined __USE_LARGEFILE64
 261 /* This function is like `scandir' but it uses the 64bit dirent structure.
 262    Please note that the CMP function must now work with struct dirent64 **.  */
 263 extern int scandir64 (__const char *__restrict __dir,
 264                       struct dirent64 ***__restrict __namelist,
 265                       int (*__selector) (__const struct dirent64 *),
 266                       int (*__cmp) (__const void *, __const void *))
 267      __nonnull ((1, 2));
 268 # endif
 269
 270 /* Function to compare two `struct dirent's alphabetically.  */
 271 # ifndef __USE_FILE_OFFSET64
 272 extern int alphasort (__const void *__e1, __const void *__e2)
 273      __THROW __attribute_pure__ __nonnull ((1, 2));
 274 # else
 275 #  ifdef __REDIRECT
 276 extern int __REDIRECT_NTH (alphasort,
 277                            (__const void *__e1, __const void *__e2),
 278                            alphasort64) __attribute_pure__ __nonnull ((1, 2));
 279 #  else
 280 #   define alphasort alphasort64
 281 #  endif
 282 # endif
 283
 284 # if defined __USE_GNU && defined __USE_LARGEFILE64
 285 extern int alphasort64 (__const void *__e1, __const void *__e2)
 286      __THROW __attribute_pure__ __nonnull ((1, 2));
 287 # endif
 288
 289 # ifdef __USE_GNU
 290 /* Function to compare two `struct dirent's by name & version.  */
 291 #  ifndef __USE_FILE_OFFSET64
 292 extern int versionsort (__const void *__e1, __const void *__e2)
 293      __THROW __attribute_pure__ __nonnull ((1, 2));
 294 #  else
 295 #   ifdef __REDIRECT
 296 extern int __REDIRECT_NTH (versionsort,
 297                            (__const void *__e1, __const void *__e2),
 298                            versionsort64)
 299      __attribute_pure__ __nonnull ((1, 2));
 300 #   else
 301 #    define versionsort versionsort64
 302 #   endif
 303 #  endif
 304
 305 #  ifdef __USE_LARGEFILE64
 306 extern int versionsort64 (__const void *__e1, __const void *__e2)
 307      __THROW __attribute_pure__ __nonnull ((1, 2));
 308 #  endif
 309 # endif
 310
 311 /* Read directory entries from FD into BUF, reading at most NBYTES.
 312    Reading starts at offset *BASEP, and *BASEP is updated with the new
 313    position after reading.  Returns the number of bytes read; zero when at
 314    end of directory; or -1 for errors.  */
 315 # ifndef __USE_FILE_OFFSET64
 316 extern __ssize_t getdirentries (int __fd, char *__restrict __buf,
 317                                 size_t __nbytes,
 318                                 __off_t *__restrict __basep)
 319      __THROW __nonnull ((2, 4));
 320 # else
 321 #  ifdef __REDIRECT
 322 extern __ssize_t __REDIRECT_NTH (getdirentries,
 323                                  (int __fd, char *__restrict __buf,
 324                                   size_t __nbytes,
 325                                   __off64_t *__restrict __basep),
 326                                  getdirentries64) __nonnull ((2, 4));
 327 #  else
 328 #   define getdirentries getdirentries64
 329 #  endif
 330 # endif
 331
 332 # ifdef __USE_LARGEFILE64
 333 extern __ssize_t getdirentries64 (int __fd, char *__restrict __buf,
 334                                   size_t __nbytes,
 335                                   __off64_t *__restrict __basep)
 336      __THROW __nonnull ((2, 4));
 337 # endif
 338
 339 #endif /* Use BSD or misc.  */
 340
 341 __END_DECLS
 342
 343 #endif /* dirent.h  */