gl/opendir.c

   1 /* Start reading the entries of a directory.
   2    Copyright (C) 2006-2012 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program 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
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  16
  17 #include <config.h>
  18
  19 /* Specification.  */
  20 #include <dirent.h>
  21
  22 #include <errno.h>
  23 #include <stddef.h>
  24
  25 #if HAVE_OPENDIR
  26
  27 /* Override opendir(), to keep track of the open file descriptors.
  28    Needed because there is a function dirfd().  */
  29
  30 #else
  31
  32 # include <stdlib.h>
  33
  34 # include "dirent-private.h"
  35 # include "filename.h"
  36
  37 #endif
  38
  39 #if REPLACE_FCHDIR
  40 # include <unistd.h>
  41 #endif
  42
  43 DIR *
  44 opendir (const char *dir_name)
  45 {
  46 #if HAVE_OPENDIR
  47 # undef opendir
  48   DIR *dirp;
  49
  50   dirp = opendir (dir_name);
  51   if (dirp == NULL)
  52     return NULL;
  53
  54 #else
  55
  56   char dir_name_mask[MAX_PATH + 1 + 1 + 1];
  57   int status;
  58   HANDLE current;
  59   WIN32_FIND_DATA entry;
  60   struct gl_directory *dirp;
  61
  62   if (dir_name[0] == '\0')
  63     {
  64       errno = ENOENT;
  65       return NULL;
  66     }
  67
  68   /* Make the dir_name absolute, so that we continue reading the same
  69      directory if the current directory changed between this opendir()
  70      call and a subsequent rewinddir() call.  */
  71   if (!GetFullPathName (dir_name, MAX_PATH, dir_name_mask, NULL))
  72     {
  73       errno = EINVAL;
  74       return NULL;
  75     }
  76
  77   /* Append the mask.
  78      "*" and "*.*" appear to be equivalent.  */
  79   {
  80     char *p;
  81
  82     p = dir_name_mask + strlen (dir_name_mask);
  83     if (p > dir_name_mask && !ISSLASH (p[-1]))
  84       *p++ = '\\';
  85     *p++ = '*';
  86     *p = '\0';
  87   }
  88
  89   /* Start searching the directory.  */
  90   status = -1;
  91   current = FindFirstFile (dir_name_mask, &entry);
  92   if (current == INVALID_HANDLE_VALUE)
  93     {
  94       switch (GetLastError ())
  95         {
  96         case ERROR_FILE_NOT_FOUND:
  97           status = -2;
  98           break;
  99         case ERROR_PATH_NOT_FOUND:
 100           errno = ENOENT;
 101           return NULL;
 102         case ERROR_DIRECTORY:
 103           errno = ENOTDIR;
 104           return NULL;
 105         case ERROR_ACCESS_DENIED:
 106           errno = EACCES;
 107           return NULL;
 108         default:
 109           errno = EIO;
 110           return NULL;
 111         }
 112     }
 113
 114   /* Allocate the result.  */
 115   dirp =
 116     (struct gl_directory *)
 117     malloc (offsetof (struct gl_directory, dir_name_mask[0])
 118             + strlen (dir_name_mask) + 1);
 119   if (dirp == NULL)
 120     {
 121       if (current != INVALID_HANDLE_VALUE)
 122         FindClose (current);
 123       errno = ENOMEM;
 124       return NULL;
 125     }
 126   dirp->status = status;
 127   dirp->current = current;
 128   if (status == -1)
 129     memcpy (&dirp->entry, &entry, sizeof (WIN32_FIND_DATA));
 130   strcpy (dirp->dir_name_mask, dir_name_mask);
 131
 132 #endif
 133
 134 #if REPLACE_FCHDIR
 135   {
 136     int fd = dirfd (dirp);
 137     if (0 <= fd && _gl_register_fd (fd, dir_name) != fd)
 138       {
 139         int saved_errno = errno;
 140         closedir (dirp);
 141         errno = saved_errno;
 142         return NULL;
 143       }
 144   }
 145 #endif
 146
 147   return dirp;
 148 }