include/dirent.h

   1 /* Copyright (C) 1991-2000, 2003-2005, 2009 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 libc_hidden_proto(opendir)
 137
 138 #ifdef __USE_XOPEN2K8
 139 /* Same as opendir, but open the stream on the file descriptor FD.
 140
 141    This function is a possible cancellation point and therefore not
 142    marked with __THROW.  */
 143 extern DIR *fdopendir (int __fd);
 144 #endif
 145
 146 /* Close the directory stream DIRP.
 147    Return 0 if successful, -1 if not.
 148
 149    This function is a possible cancellation point and therefore not
 150    marked with __THROW.  */
 151 extern int closedir (DIR *__dirp) __nonnull ((1));
 152 libc_hidden_proto(closedir)
 153
 154 /* Read a directory entry from DIRP.  Return a pointer to a `struct
 155    dirent' describing the entry, or NULL for EOF or error.  The
 156    storage returned may be overwritten by a later readdir call on the
 157    same DIR stream.
 158
 159    If the Large File Support API is selected we have to use the
 160    appropriate interface.
 161
 162    This function is a possible cancellation point and therefore not
 163    marked with __THROW.  */
 164 #ifndef __USE_FILE_OFFSET64
 165 extern struct dirent *readdir (DIR *__dirp) __nonnull ((1));
 166 libc_hidden_proto(readdir)
 167 #else
 168 # ifdef __REDIRECT
 169 extern struct dirent *__REDIRECT (readdir, (DIR *__dirp), readdir64)
 170      __nonnull ((1));
 171 # else
 172 #  define readdir readdir64
 173 # endif
 174 #endif
 175
 176 #ifdef __USE_LARGEFILE64
 177 extern struct dirent64 *readdir64 (DIR *__dirp) __nonnull ((1));
 178 libc_hidden_proto(readdir64)
 179 #endif
 180
 181 #if defined __USE_POSIX || defined __USE_MISC
 182 /* Reentrant version of `readdir'.  Return in RESULT a pointer to the
 183    next entry.
 184
 185    This function is a possible cancellation point and therefore not
 186    marked with __THROW.  */
 187 # ifndef __USE_FILE_OFFSET64
 188 extern int readdir_r (DIR *__restrict __dirp,
 189                       struct dirent *__restrict __entry,
 190                       struct dirent **__restrict __result)
 191      __nonnull ((1, 2, 3));
 192 libc_hidden_proto(readdir_r)
 193 # else
 194 #  ifdef __REDIRECT
 195 extern int __REDIRECT (readdir_r,
 196                        (DIR *__restrict __dirp,
 197                         struct dirent *__restrict __entry,
 198                         struct dirent **__restrict __result),
 199                        readdir64_r) __nonnull ((1, 2, 3));
 200 #  else
 201 #   define readdir_r readdir64_r
 202 #  endif
 203 # endif
 204
 205 # ifdef __USE_LARGEFILE64
 206 extern int readdir64_r (DIR *__restrict __dirp,
 207                         struct dirent64 *__restrict __entry,
 208                         struct dirent64 **__restrict __result)
 209      __nonnull ((1, 2, 3));
 210 libc_hidden_proto(readdir64_r)
 211 # endif
 212 #endif  /* POSIX or misc */
 213
 214 /* Rewind DIRP to the beginning of the directory.  */
 215 extern void rewinddir (DIR *__dirp) __THROW __nonnull ((1));
 216
 217 #if defined __USE_BSD || defined __USE_MISC || defined __USE_XOPEN
 218 # include <bits/types.h>
 219
 220 /* Seek to position POS on DIRP.  */
 221 extern void seekdir (DIR *__dirp, long int __pos) __THROW __nonnull ((1));
 222
 223 /* Return the current position of DIRP.  */
 224 extern long int telldir (DIR *__dirp) __THROW __nonnull ((1));
 225 #endif
 226
 227 #if defined __USE_BSD || defined __USE_MISC || defined __XOPEN_2K8
 228
 229 /* Return the file descriptor used by DIRP.  */
 230 extern int dirfd (DIR *__dirp) __THROW __nonnull ((1));
 231 libc_hidden_proto(dirfd)
 232
 233 # if 0 /* defined __OPTIMIZE__ && defined _DIR_dirfd */
 234 #  define dirfd(dirp)   _DIR_dirfd (dirp)
 235 # endif
 236
 237 # if defined __USE_BSD || defined __USE_MISC
 238 #  ifndef MAXNAMLEN
 239 /* Get the definitions of the POSIX.1 limits.  */
 240 #  include <bits/posix1_lim.h>
 241
 242 /* `MAXNAMLEN' is the BSD name for what POSIX calls `NAME_MAX'.  */
 243 #   ifdef NAME_MAX
 244 #    define MAXNAMLEN   NAME_MAX
 245 #   else
 246 #    define MAXNAMLEN   255
 247 #   endif
 248 #  endif
 249 # endif
 250
 251 # define __need_size_t
 252 # include <stddef.h>
 253
 254 /* Scan the directory DIR, calling SELECTOR on each directory entry.
 255    Entries for which SELECT returns nonzero are individually malloc'd,
 256    sorted using qsort with CMP, and collected in a malloc'd array in
 257    *NAMELIST.  Returns the number of entries selected, or -1 on error.  */
 258 # ifndef __USE_FILE_OFFSET64
 259 extern int scandir (__const char *__restrict __dir,
 260                     struct dirent ***__restrict __namelist,
 261                     int (*__selector) (__const struct dirent *),
 262                     int (*__cmp) (__const struct dirent **,
 263                                   __const struct dirent **))
 264      __nonnull ((1, 2));
 265 # else
 266 #  ifdef __REDIRECT
 267 extern int __REDIRECT (scandir,
 268                        (__const char *__restrict __dir,
 269                         struct dirent ***__restrict __namelist,
 270                         int (*__selector) (__const struct dirent *),
 271                         int (*__cmp) (__const struct dirent **,
 272                                       __const struct dirent **)),
 273                        scandir64) __nonnull ((1, 2));
 274 #  else
 275 #   define scandir scandir64
 276 #  endif
 277 # endif
 278
 279 # if defined __USE_GNU && defined __USE_LARGEFILE64
 280 /* This function is like `scandir' but it uses the 64bit dirent structure.
 281    Please note that the CMP function must now work with struct dirent64 **.  */
 282 extern int scandir64 (__const char *__restrict __dir,
 283                       struct dirent64 ***__restrict __namelist,
 284                       int (*__selector) (__const struct dirent64 *),
 285                       int (*__cmp) (__const struct dirent64 **,
 286                                     __const struct dirent64 **))
 287      __nonnull ((1, 2));
 288 # endif
 289
 290 /* Function to compare two `struct dirent's alphabetically.  */
 291 # ifndef __USE_FILE_OFFSET64
 292 extern int alphasort (__const struct dirent **__e1,
 293                       __const struct dirent **__e2)
 294      __THROW __attribute_pure__ __nonnull ((1, 2));
 295 # else
 296 #  ifdef __REDIRECT
 297 extern int __REDIRECT_NTH (alphasort,
 298                            (__const struct dirent **__e1,
 299                             __const struct dirent **__e2),
 300                            alphasort64) __attribute_pure__ __nonnull ((1, 2));
 301 #  else
 302 #   define alphasort alphasort64
 303 #  endif
 304 # endif
 305
 306 # if defined __USE_GNU && defined __USE_LARGEFILE64
 307 extern int alphasort64 (__const struct dirent64 **__e1,
 308                         __const struct dirent64 **__e2)
 309      __THROW __attribute_pure__ __nonnull ((1, 2));
 310 # endif
 311 #endif /* Use BSD or misc or XPG7.  */
 312
 313
 314 #if defined __USE_BSD || defined __USE_MISC
 315 /* Read directory entries from FD into BUF, reading at most NBYTES.
 316    Reading starts at offset *BASEP, and *BASEP is updated with the new
 317    position after reading.  Returns the number of bytes read; zero when at
 318    end of directory; or -1 for errors.  */
 319 # ifndef __USE_FILE_OFFSET64
 320 extern __ssize_t getdirentries (int __fd, char *__restrict __buf,
 321                                 size_t __nbytes,
 322                                 __off_t *__restrict __basep)
 323      __THROW __nonnull ((2, 4));
 324 # else
 325 #  ifdef __REDIRECT
 326 extern __ssize_t __REDIRECT_NTH (getdirentries,
 327                                  (int __fd, char *__restrict __buf,
 328                                   size_t __nbytes,
 329                                   __off64_t *__restrict __basep),
 330                                  getdirentries64) __nonnull ((2, 4));
 331 #  else
 332 #   define getdirentries getdirentries64
 333 #  endif
 334 # endif
 335
 336 # ifdef __USE_LARGEFILE64
 337 extern __ssize_t getdirentries64 (int __fd, char *__restrict __buf,
 338                                   size_t __nbytes,
 339                                   __off64_t *__restrict __basep)
 340      __THROW __nonnull ((2, 4));
 341 # endif
 342 #endif /* Use BSD or misc.  */
 343
 344 #ifdef __USE_GNU
 345 /* Function to compare two `struct dirent's by name & version.  */
 346 # ifndef __USE_FILE_OFFSET64
 347 extern int versionsort (__const struct dirent **__e1,
 348                         __const struct dirent **__e2)
 349      __THROW __attribute_pure__ __nonnull ((1, 2));
 350 # else
 351 #  ifdef __REDIRECT
 352 extern int __REDIRECT_NTH (versionsort,
 353                            (__const struct dirent **__e1,
 354                             __const struct dirent **__e2),
 355                            versionsort64)
 356      __attribute_pure__ __nonnull ((1, 2));
 357 #  else
 358 #   define versionsort versionsort64
 359 #  endif
 360 # endif
 361
 362 # ifdef __USE_LARGEFILE64
 363 extern int versionsort64 (__const struct dirent64 **__e1,
 364                           __const struct dirent64 **__e2)
 365      __THROW __attribute_pure__ __nonnull ((1, 2));
 366 # endif
 367 #endif /* Use GNU.  */
 368
 369 __END_DECLS
 370
 371 #endif /* dirent.h  */