dirent/dirent.h

   1 /* Copyright (C) 1991, 92, 93, 94, 95, 96, 97 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     DT_FIFO = 1,
  87     DT_CHR = 2,
  88     DT_DIR = 4,
  89     DT_BLK = 6,
  90     DT_REG = 8,
  91     DT_LNK = 10,
  92     DT_SOCK = 12
  93   };
  94
  95 /* Convert between stat structure types and directory types.  */
  96 # define IFTODT(mode)   (((mode) & 0170000) >> 12)
  97 # define DTTOIF(dirtype)        ((dirtype) << 12)
  98 #endif
  99
 100
 101 /* This is the data type of directory stream objects.
 102    The actual structure is opaque to users.  */
 103 typedef struct __dirstream DIR;
 104
 105 /* Open a directory stream on NAME.
 106    Return a DIR stream on the directory, or NULL if it could not be opened.  */
 107 extern DIR *__opendir __P ((__const char *__name));
 108 extern DIR *opendir __P ((__const char *__name));
 109
 110 /* Close the directory stream DIRP.
 111    Return 0 if successful, -1 if not.  */
 112 extern int __closedir __P ((DIR *__dirp));
 113 extern int closedir __P ((DIR *__dirp));
 114
 115 /* Read a directory entry from DIRP.  Return a pointer to a `struct
 116    dirent' describing the entry, or NULL for EOF or error.  The
 117    storage returned may be overwritten by a later readdir call on the
 118    same DIR stream.
 119
 120    If the Large File Support API is selected we have to use the
 121    appropriate interface.  */
 122 extern struct dirent *__readdir __P ((DIR *__dirp));
 123 #ifndef __USE_FILE_OFFSET64
 124 extern struct dirent *readdir __P ((DIR *__dirp));
 125 #else
 126 extern struct dirent64 *readdir __P ((DIR *__dirp)) __asm__ ("readdir64");
 127 #endif
 128
 129 #ifdef __USE_LARGEFILE64
 130 extern struct dirent64 *readdir64 __P ((DIR *__dirp));
 131 #endif
 132
 133 #if defined __USE_POSIX || defined __USE_MISC
 134 /* Reentrant version of `readdir'.  Return in RESULT a pointer to the
 135    next entry.  */
 136 extern int __readdir_r __P ((DIR *__dirp, struct dirent *__entry,
 137                              struct dirent **__result));
 138 # ifndef __USE_FILE_OFFSET64
 139 extern int readdir_r __P ((DIR *__dirp, struct dirent *__entry,
 140                            struct dirent **__result));
 141 # else
 142 extern int readdir_r __P ((DIR *__dirp, struct dirent64 *__entry,
 143                            struct dirent64 **__result))
 144      __asm__ ("readdir64_r");
 145 # endif
 146
 147 # ifdef __USE_LARGEFILE64
 148 extern int readdir64_r __P ((DIR *__dirp, struct dirent64 *__entry,
 149                              struct dirent64 **__result));
 150 # endif
 151 #endif  /* POSIX or misc */
 152
 153 /* Rewind DIRP to the beginning of the directory.  */
 154 extern void rewinddir __P ((DIR *__dirp));
 155
 156 #if defined __USE_BSD || defined __USE_MISC || defined __USE_XOPEN
 157 # include <bits/types.h>
 158
 159 /* Seek to position POS on DIRP.  */
 160 extern void seekdir __P ((DIR *__dirp, __off_t __pos));
 161
 162 /* Return the current position of DIRP.  */
 163 extern __off_t telldir __P ((DIR *__dirp));
 164 #endif
 165
 166 #if defined __USE_BSD || defined __USE_MISC
 167
 168 /* Return the file descriptor used by DIRP.  */
 169 extern int dirfd __P ((DIR *__dirp));
 170
 171 # if defined __OPTIMIZE__ && defined _DIR_dirfd
 172 #  define dirfd(dirp)   _DIR_dirfd (dirp)
 173 # endif
 174
 175 # ifndef MAXNAMLEN
 176 /* Get the definitions of the POSIX.1 limits.  */
 177 #  include <bits/posix1_lim.h>
 178
 179 /* `MAXNAMLEN' is the BSD name for what POSIX calls `NAME_MAX'.  */
 180 #  ifdef NAME_MAX
 181 #   define MAXNAMLEN    NAME_MAX
 182 #  else
 183 #   define MAXNAMLEN    255
 184 #  endif
 185 # endif
 186
 187 # define __need_size_t
 188 # include <stddef.h>
 189
 190 /* Scan the directory DIR, calling SELECTOR on each directory entry.
 191    Entries for which SELECT returns nonzero are individually malloc'd,
 192    sorted using qsort with CMP, and collected in a malloc'd array in
 193    *NAMELIST.  Returns the number of entries selected, or -1 on error.  */
 194 extern int scandir __P ((__const char *__dir,
 195                          struct dirent ***__namelist,
 196                          int (*__selector) __P ((struct dirent *)),
 197                          int (*__cmp) __P ((__const __ptr_t,
 198                                             __const __ptr_t))));
 199
 200 /* Function to compare two `struct dirent's alphabetically.  */
 201 extern int alphasort __P ((__const __ptr_t, __const __ptr_t));
 202
 203 # ifdef __USE_GNU
 204 /* Function to compare two `struct dirent's by name & version.  */
 205 extern int versionsort __P ((__const __ptr_t, __const __ptr_t));
 206 # endif
 207
 208 /* Read directory entries from FD into BUF, reading at most NBYTES.
 209    Reading starts at offset *BASEP, and *BASEP is updated with the new
 210    position after reading.  Returns the number of bytes read; zero when at
 211    end of directory; or -1 for errors.  */
 212 extern __ssize_t __getdirentries __P ((int __fd, char *__buf,
 213                                        size_t __nbytes, __off_t *__basep));
 214 extern __ssize_t getdirentries __P ((int __fd, char *__buf,
 215                                      size_t __nbytes, __off_t *__basep));
 216
 217
 218 #endif /* Use BSD or misc.  */
 219
 220 __END_DECLS
 221
 222 #endif /* dirent.h  */