dirent/dirent.h

   1 /* Copyright (C) 1991-1999, 2000 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 extern DIR *opendir (__const char *__name) __THROW;
 133
 134 /* Close the directory stream DIRP.
 135    Return 0 if successful, -1 if not.  */
 136 extern int closedir (DIR *__dirp) __THROW;
 137
 138 /* Read a directory entry from DIRP.  Return a pointer to a `struct
 139    dirent' describing the entry, or NULL for EOF or error.  The
 140    storage returned may be overwritten by a later readdir call on the
 141    same DIR stream.
 142
 143    If the Large File Support API is selected we have to use the
 144    appropriate interface.  */
 145 #ifndef __USE_FILE_OFFSET64
 146 extern struct dirent *readdir (DIR *__dirp) __THROW;
 147 #else
 148 # ifdef __REDIRECT
 149 extern struct dirent *__REDIRECT (readdir, (DIR *__dirp) __THROW, readdir64);
 150 # else
 151 #  define readdir readdir64
 152 # endif
 153 #endif
 154
 155 #ifdef __USE_LARGEFILE64
 156 extern struct dirent64 *readdir64 (DIR *__dirp) __THROW;
 157 #endif
 158
 159 #if defined __USE_POSIX || defined __USE_MISC
 160 /* Reentrant version of `readdir'.  Return in RESULT a pointer to the
 161    next entry.  */
 162 # ifndef __USE_FILE_OFFSET64
 163 extern int readdir_r (DIR *__restrict __dirp,
 164                       struct dirent *__restrict __entry,
 165                       struct dirent **__restrict __result) __THROW;
 166 # else
 167 #  ifdef __REDIRECT
 168 extern int __REDIRECT (readdir_r,
 169                        (DIR *__restrict __dirp,
 170                         struct dirent *__restrict __entry,
 171                         struct dirent **__restrict __result) __THROW,
 172                        readdir64_r);
 173 #  else
 174 #   define readdir_r readdir64_r
 175 #  endif
 176 # endif
 177
 178 # ifdef __USE_LARGEFILE64
 179 extern int readdir64_r (DIR *__restrict __dirp,
 180                         struct dirent64 *__restrict __entry,
 181                         struct dirent64 **__restrict __result) __THROW;
 182 # endif
 183 #endif  /* POSIX or misc */
 184
 185 /* Rewind DIRP to the beginning of the directory.  */
 186 extern void rewinddir (DIR *__dirp) __THROW;
 187
 188 #if defined __USE_BSD || defined __USE_MISC || defined __USE_XOPEN
 189 # include <bits/types.h>
 190
 191 /* Seek to position POS on DIRP.  */
 192 extern void seekdir (DIR *__dirp, long int __pos) __THROW;
 193
 194 /* Return the current position of DIRP.  */
 195 extern long int telldir (DIR *__dirp) __THROW;
 196 #endif
 197
 198 #if defined __USE_BSD || defined __USE_MISC
 199
 200 /* Return the file descriptor used by DIRP.  */
 201 extern int dirfd (DIR *__dirp) __THROW;
 202
 203 # if defined __OPTIMIZE__ && defined _DIR_dirfd
 204 #  define dirfd(dirp)   _DIR_dirfd (dirp)
 205 # endif
 206
 207 # ifndef MAXNAMLEN
 208 /* Get the definitions of the POSIX.1 limits.  */
 209 #  include <bits/posix1_lim.h>
 210
 211 /* `MAXNAMLEN' is the BSD name for what POSIX calls `NAME_MAX'.  */
 212 #  ifdef NAME_MAX
 213 #   define MAXNAMLEN    NAME_MAX
 214 #  else
 215 #   define MAXNAMLEN    255
 216 #  endif
 217 # endif
 218
 219 # define __need_size_t
 220 # include <stddef.h>
 221
 222 /* Scan the directory DIR, calling SELECTOR on each directory entry.
 223    Entries for which SELECT returns nonzero are individually malloc'd,
 224    sorted using qsort with CMP, and collected in a malloc'd array in
 225    *NAMELIST.  Returns the number of entries selected, or -1 on error.  */
 226 # ifndef __USE_FILE_OFFSET64
 227 extern int scandir (__const char *__restrict __dir,
 228                     struct dirent ***__restrict __namelist,
 229                     int (*__selector) (__const struct dirent *),
 230                     int (*__cmp) (__const void *, __const void *)) __THROW;
 231 # else
 232 #  ifdef __REDIRECT
 233 extern int __REDIRECT (scandir,
 234                        (__const char *__restrict __dir,
 235                         struct dirent ***__restrict __namelist,
 236                         int (*__selector) (__const struct dirent *),
 237                         int (*__cmp) (__const void *, __const void *)) __THROW,
 238                        scandir64);
 239 #  else
 240 #   define scandir scandir64
 241 #  endif
 242 # endif
 243
 244 # if defined __USE_GNU && defined __USE_LARGEFILE64
 245 /* This function is like `scandir' but it uses the 64bit dirent structure.
 246    Please note that the CMP function must now work with struct dirent64 **.  */
 247 extern int scandir64 (__const char *__restrict __dir,
 248                       struct dirent64 ***__restrict __namelist,
 249                       int (*__selector) (__const struct dirent64 *),
 250                       int (*__cmp) (__const void *, __const void *)) __THROW;
 251 # endif
 252
 253 /* Function to compare two `struct dirent's alphabetically.  */
 254 # ifndef __USE_FILE_OFFSET64
 255 extern int alphasort (__const void *__e1, __const void *__e2)
 256      __THROW __attribute_pure__;
 257 # else
 258 #  ifdef __REDIRECT
 259 extern int __REDIRECT (alphasort,
 260                        (__const void *__e1, __const void *__e2)
 261                        __THROW,
 262                        alphasort64) __attribute_pure__;
 263 #  else
 264 #   define alphasort alphasort64
 265 #  endif
 266 # endif
 267
 268 # if defined __USE_GNU && defined __USE_LARGEFILE64
 269 extern int alphasort64 (__const void *__e1, __const void *__e2)
 270      __THROW __attribute_pure__;
 271 # endif
 272
 273 # ifdef __USE_GNU
 274 /* Function to compare two `struct dirent's by name & version.  */
 275 #  ifndef __USE_FILE_OFFSET64
 276 extern int versionsort (__const void *__e1, __const void *__e2)
 277      __THROW __attribute_pure__;
 278 #  else
 279 #   ifdef __REDIRECT
 280 extern int __REDIRECT (versionsort,
 281                        (__const void *__e1, __const void *__e2)
 282                        __THROW,
 283                        versionsort64) __attribute_pure__;
 284 #   else
 285 #    define versionsort versionsort64
 286 #   endif
 287 #  endif
 288
 289 #  ifdef __USE_LARGEFILE64
 290 extern int versionsort64 (__const void *__e1, __const void *__e2)
 291      __THROW __attribute_pure__;
 292 #  endif
 293 # endif
 294
 295 /* Read directory entries from FD into BUF, reading at most NBYTES.
 296    Reading starts at offset *BASEP, and *BASEP is updated with the new
 297    position after reading.  Returns the number of bytes read; zero when at
 298    end of directory; or -1 for errors.  */
 299 # ifndef __USE_FILE_OFFSET64
 300 extern __ssize_t getdirentries (int __fd, char *__restrict __buf,
 301                                 size_t __nbytes,
 302                                 __off_t *__restrict __basep) __THROW;
 303 # else
 304 #  ifdef __REDIRECT
 305 extern __ssize_t __REDIRECT (getdirentries,
 306                              (int __fd, char *__restrict __buf,
 307                               size_t __nbytes,
 308                               __off64_t *__restrict __basep) __THROW,
 309                              getdirentries64);
 310 #  else
 311 #   define getdirentries getdirentries64
 312 #  endif
 313 # endif
 314
 315 # ifdef __USE_LARGEFILE64
 316 extern __ssize_t getdirentries64 (int __fd, char *__restrict __buf,
 317                                   size_t __nbytes,
 318                                   __off64_t *__restrict __basep) __THROW;
 319 # endif
 320
 321 #endif /* Use BSD or misc.  */
 322
 323 __END_DECLS
 324
 325 #endif /* dirent.h  */