dirent/dirent.h

   1 /* Copyright (C) 1991,92,93,94,95,96,97,98 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 Library General Public License as
   6    published by the Free Software Foundation; either version 2 of the
   7    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    Library General Public License for more details.
  13
  14    You should have received a copy of the GNU Library General Public
  15    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  16    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17    Boston, MA 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 /* This file defines `struct dirent'.
  33
  34    It defines the macro `_DIRENT_HAVE_D_NAMLEN' iff there is a `d_namlen'
  35    member that gives the length of `d_name'.
  36
  37    It defines the macro `_DIRENT_HAVE_D_RECLEN' iff there is a `d_reclen'
  38    member that gives the size of the entire directory entry.
  39
  40    It defines the macro `_DIRENT_HAVE_D_OFF' iff there is a `d_off'
  41    member that gives the file offset of the next directory entry.
  42
  43    It defines the macro `_DIRENT_HAVE_D_TYPE' iff there is a `d_type'
  44    member that gives the type of the file.
  45  */
  46
  47 #include <bits/dirent.h>
  48
  49 #if (defined __USE_BSD || defined __USE_MISC) && !defined d_fileno
  50 # define d_ino  d_fileno                 /* Backward compatibility.  */
  51 #endif
  52
  53 /* These macros extract size information from a `struct dirent *'.
  54    They may evaluate their argument multiple times, so it must not
  55    have side effects.  Each of these may involve a relatively costly
  56    call to `strlen' on some systems, so these values should be cached.
  57
  58    _D_EXACT_NAMLEN (DP) returns the length of DP->d_name, not including
  59    its terminating null character.
  60
  61    _D_ALLOC_NAMLEN (DP) returns a size at least (_D_EXACT_NAMLEN (DP) + 1);
  62    that is, the allocation size needed to hold the DP->d_name string.
  63    Use this macro when you don't need the exact length, just an upper bound.
  64    This macro is less likely to require calling `strlen' than _D_EXACT_NAMLEN.
  65    */
  66
  67 #ifdef _DIRENT_HAVE_D_NAMLEN
  68 # define _D_EXACT_NAMLEN(d) ((d)->d_namlen)
  69 # define _D_ALLOC_NAMLEN(d) (_D_EXACT_NAMLEN (d) + 1)
  70 #else
  71 # define _D_EXACT_NAMLEN(d) (strlen ((d)->d_name))
  72 # ifdef _DIRENT_HAVE_D_RECLEN
  73 #  define _D_ALLOC_NAMLEN(d) (((char *) (d) + (d)->d_reclen) - &(d)->d_name[0])
  74 # else
  75 #  define _D_ALLOC_NAMLEN(d) (sizeof (d)->d_name > 1 ? sizeof (d)->d_name : \
  76                               _D_EXACT_NAMLEN (d) + 1)
  77 # endif
  78 #endif
  79
  80
  81 #ifdef __USE_BSD
  82 /* File types for `d_type'.  */
  83 enum
  84   {
  85     DT_UNKNOWN = 0,
  86 # define DT_UNKNOWN     DT_UNKNOWN
  87     DT_FIFO = 1,
  88 # define DT_FIFO        DT_FIFO
  89     DT_CHR = 2,
  90 # define DT_CHR         DT_CHR
  91     DT_DIR = 4,
  92 # define DT_DIR         DT_DIR
  93     DT_BLK = 6,
  94 # define DT_BLK         DT_BLK
  95     DT_REG = 8,
  96 # define DT_REG         DT_REG
  97     DT_LNK = 10,
  98 # define DT_LNK         DT_LNK
  99     DT_SOCK = 12
 100 # define DT_SOCK        DT_SOCK
 101   };
 102
 103 /* Convert between stat structure types and directory types.  */
 104 # define IFTODT(mode)   (((mode) & 0170000) >> 12)
 105 # define DTTOIF(dirtype)        ((dirtype) << 12)
 106 #endif
 107
 108
 109 /* This is the data type of directory stream objects.
 110    The actual structure is opaque to users.  */
 111 typedef struct __dirstream DIR;
 112
 113 /* Open a directory stream on NAME.
 114    Return a DIR stream on the directory, or NULL if it could not be opened.  */
 115 extern DIR *opendir __P ((__const char *__name));
 116
 117 /* Close the directory stream DIRP.
 118    Return 0 if successful, -1 if not.  */
 119 extern int closedir __P ((DIR *__dirp));
 120
 121 /* Read a directory entry from DIRP.  Return a pointer to a `struct
 122    dirent' describing the entry, or NULL for EOF or error.  The
 123    storage returned may be overwritten by a later readdir call on the
 124    same DIR stream.
 125
 126    If the Large File Support API is selected we have to use the
 127    appropriate interface.  */
 128 #ifndef __USE_FILE_OFFSET64
 129 extern struct dirent *readdir __P ((DIR *__dirp));
 130 #else
 131 # ifdef __REDIRECT
 132 extern struct dirent *__REDIRECT (readdir, __P ((DIR *__dirp)), readdir64);
 133 # else
 134 #  define readdir readdir64
 135 # endif
 136 #endif
 137
 138 #ifdef __USE_LARGEFILE64
 139 extern struct dirent64 *readdir64 __P ((DIR *__dirp));
 140 #endif
 141
 142 #if defined __USE_POSIX || defined __USE_MISC
 143 /* Reentrant version of `readdir'.  Return in RESULT a pointer to the
 144    next entry.  */
 145 # ifndef __USE_FILE_OFFSET64
 146 extern int readdir_r __P ((DIR *__restrict __dirp,
 147                            struct dirent *__restrict __entry,
 148                            struct dirent **__restrict __result));
 149 # else
 150 #  ifdef __REDIRECT
 151 extern int __REDIRECT (readdir_r, __P ((DIR *__restrict __dirp,
 152                                         struct dirent *__restrict __entry,
 153                                         struct dirent **__restrict __result)),
 154                     readdir64_r);
 155 #  else
 156 #   define readdir_r readdir64_r
 157 #  endif
 158 # endif
 159
 160 # ifdef __USE_LARGEFILE64
 161 extern int readdir64_r __P ((DIR *__restrict __dirp,
 162                              struct dirent64 *__restrict __entry,
 163                              struct dirent64 **__restrict __result));
 164 # endif
 165 #endif  /* POSIX or misc */
 166
 167 /* Rewind DIRP to the beginning of the directory.  */
 168 extern void rewinddir __P ((DIR *__dirp));
 169
 170 #if defined __USE_BSD || defined __USE_MISC || defined __USE_XOPEN
 171 # include <bits/types.h>
 172
 173 /* Seek to position POS on DIRP.  */
 174 extern void seekdir __P ((DIR *__dirp, __off_t __pos));
 175
 176 /* Return the current position of DIRP.  */
 177 extern __off_t telldir __P ((DIR *__dirp));
 178 #endif
 179
 180 #if defined __USE_BSD || defined __USE_MISC
 181
 182 /* Return the file descriptor used by DIRP.  */
 183 extern int dirfd __P ((DIR *__dirp));
 184
 185 # if defined __OPTIMIZE__ && defined _DIR_dirfd
 186 #  define dirfd(dirp)   _DIR_dirfd (dirp)
 187 # endif
 188
 189 # ifndef MAXNAMLEN
 190 /* Get the definitions of the POSIX.1 limits.  */
 191 #  include <bits/posix1_lim.h>
 192
 193 /* `MAXNAMLEN' is the BSD name for what POSIX calls `NAME_MAX'.  */
 194 #  ifdef NAME_MAX
 195 #   define MAXNAMLEN    NAME_MAX
 196 #  else
 197 #   define MAXNAMLEN    255
 198 #  endif
 199 # endif
 200
 201 # define __need_size_t
 202 # include <stddef.h>
 203
 204 /* Scan the directory DIR, calling SELECTOR on each directory entry.
 205    Entries for which SELECT returns nonzero are individually malloc'd,
 206    sorted using qsort with CMP, and collected in a malloc'd array in
 207    *NAMELIST.  Returns the number of entries selected, or -1 on error.  */
 208 # ifndef __USE_FILE_OFFSET64
 209 extern int scandir __P ((__const char *__restrict __dir,
 210                          struct dirent ***__restrict __namelist,
 211                          int (*__selector) (__const struct dirent *),
 212                          int (*__cmp) (__const __ptr_t, __const __ptr_t)));
 213 # else
 214 #  ifdef __REDIRECT
 215 extern int __REDIRECT (scandir,
 216                        __P ((__const char *__restrict __dir,
 217                              struct dirent ***__restrict __namelist,
 218                              int (*__selector) (__const struct dirent *),
 219                              int (*__cmp) (__const __ptr_t, __const __ptr_t))),
 220                        scandir64);
 221 #  else
 222 #   define scandir scandir64
 223 #  endif
 224 # endif
 225
 226 # if defined __USE_GNU && defined __USE_LARGEFILE64
 227 /* This function is like `scandir' but it uses the 64bit dirent structure.
 228    Please note that the CMP function must now work with struct dirent64 **.  */
 229 extern int scandir64 __P ((__const char *__restrict __dir,
 230                            struct dirent64 ***__restrict __namelist,
 231                            int (*__selector) (__const struct dirent64 *),
 232                            int (*__cmp) (__const __ptr_t, __const __ptr_t)));
 233 # endif
 234
 235 /* Function to compare two `struct dirent's alphabetically.  */
 236 # ifndef __USE_FILE_OFFSET64
 237 extern int alphasort __P ((__const __ptr_t __e1, __const __ptr_t __e2));
 238 # else
 239 #  ifdef __REDIRECT
 240 extern int __REDIRECT (alphasort,
 241                        __P ((__const __ptr_t __e1, __const __ptr_t __e2)),
 242                        alphasort64);
 243 #  else
 244 #   define alphasort alphasort64
 245 #  endif
 246 # endif
 247
 248 # if defined __USE_GNU && defined __USE_LARGEFILE64
 249 extern int alphasort64 __P ((__const __ptr_t __e1, __const __ptr_t __e2));
 250 # endif
 251
 252 # ifdef __USE_GNU
 253 /* Function to compare two `struct dirent's by name & version.  */
 254 #  ifndef __USE_FILE_OFFSET64
 255 extern int versionsort __P ((__const __ptr_t __e1, __const __ptr_t __e2));
 256 #  else
 257 #   ifdef __REDIRECT
 258 extern int __REDIRECT (versionsort,
 259                        __P ((__const __ptr_t __e1, __const __ptr_t __e2)),
 260                        versionsort64);
 261 #   else
 262 #    define versionsort versionsort64
 263 #   endif
 264 #  endif
 265
 266 #  ifdef __USE_LARGEFILE64
 267 extern int versionsort64 __P ((__const __ptr_t __e1, __const __ptr_t __e2));
 268 #  endif
 269 # endif
 270
 271 /* Read directory entries from FD into BUF, reading at most NBYTES.
 272    Reading starts at offset *BASEP, and *BASEP is updated with the new
 273    position after reading.  Returns the number of bytes read; zero when at
 274    end of directory; or -1 for errors.  */
 275 extern __ssize_t getdirentries __P ((int __fd, char *__restrict __buf,
 276                                      size_t __nbytes,
 277                                      __off_t *__restrict __basep));
 278
 279
 280 #endif /* Use BSD or misc.  */
 281
 282 __END_DECLS
 283
 284 #endif /* dirent.h  */