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