minix/lib/libsffs/handle.c

   1 /* This file contains open file and directory handle management functions.
   2  *
   3  * The entry points into this file are:
   4  *   get_handle         open a handle for an inode and store the handle
   5  *   put_handle         close any handles associated with an inode
   6  *
   7  * Created:
   8  *   April 2009 (D.C. van Moolenbroek)
   9  */
  10
  11 #include "inc.h"
  12
  13 #include <fcntl.h>
  14
  15 /*===========================================================================*
  16  *                              get_handle                                   *
  17  *===========================================================================*/
  18 int get_handle(struct inode *ino)
  19 {
  20 /* Get an open file or directory handle for an inode.
  21  */
  22   char path[PATH_MAX];
  23   int r;
  24
  25   /* If we don't have a file handle yet, try to open the file now. */
  26   if (ino->i_flags & I_HANDLE)
  27         return OK;
  28
  29   if ((r = verify_inode(ino, path, NULL)) != OK)
  30         return r;
  31
  32   if (IS_DIR(ino)) {
  33         r = sffs_table->t_opendir(path, &ino->i_dir);
  34   }
  35   else {
  36         if (!read_only)
  37                 r = sffs_table->t_open(path, O_RDWR, 0, &ino->i_file);
  38
  39         /* Protection or mount status might prevent us from writing. With the
  40          * information that we have available, this is the best we can do..
  41          */
  42         if (read_only || r != OK)
  43                 r = sffs_table->t_open(path, O_RDONLY, 0, &ino->i_file);
  44   }
  45
  46   if (r != OK)
  47         return r;
  48
  49   ino->i_flags |= I_HANDLE;
  50
  51   return OK;
  52 }
  53
  54 /*===========================================================================*
  55  *                              put_handle                                   *
  56  *===========================================================================*/
  57 void put_handle(struct inode *ino)
  58 {
  59 /* Close an open file or directory handle associated with an inode.
  60  */
  61   int r;
  62
  63   if (!(ino->i_flags & I_HANDLE))
  64         return;
  65
  66   /* We ignore any errors here, because we can't deal with them anyway. */
  67   if (IS_DIR(ino))
  68         r = sffs_table->t_closedir(ino->i_dir);
  69   else
  70         r = sffs_table->t_close(ino->i_file);
  71
  72   if (r != OK)
  73         printf("%s: put_handle: handle close operation returned %d\n",
  74                 sffs_name, r);
  75
  76   ino->i_flags &= ~I_HANDLE;
  77 }