Function tmpfs_open

fs/tmpfs/fs_tmpfs.c:1366–1514

 ****************************************************************************/

static int tmpfs_open(FAR struct file *filep, FAR const char *relpath,
                      int oflags, mode_t mode)
{
  FAR struct inode *inode;
  FAR struct tmpfs_s *fs;
  FAR struct tmpfs_file_s *tfo;
  off_t offset;
  int ret;

  finfo("filep: %p\n", filep);
  DEBUGASSERT(filep->f_priv == NULL);

  /* Get the mountpoint inode reference from the file structure and the
   * mountpoint private data from the inode structure
   */

  inode = filep->f_inode;
  fs    = inode->i_private;

  DEBUGASSERT(fs != NULL && fs->tfs_root.tde_object != NULL);

  /* Get exclusive access to the file system */

  ret = tmpfs_lock(fs);
  if (ret < 0)
    {
      return ret;
    }

  /* Skip over any leading directory separators (shouldn't be any) */

  for (; *relpath == '/'; relpath++);

  /* Find the file object associated with this relative path.
   * If successful, this action will lock both the parent directory and
   * the file object, adding one to the reference count of both.
   * In the event that -ENOENT, there will still be a reference and
   * lock on the returned directory.
   */

  ret = tmpfs_find_file(fs, relpath, &tfo, NULL);
  if (ret >= 0)
    {
      /* The file exists.  We hold the lock and one reference count
       * on the file object.
       *
       * It would be an error if we are asked to create it exclusively
       */

      if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
        {
          /* Already exists -- can't create it exclusively */

          ret = -EEXIST;
          goto errout_with_filelock;
        }

      /* Check if the caller has sufficient privileges to open the file.