diff options
Diffstat (limited to 'nuttx/fs/fs_seekdir.c')
| -rw-r--r-- | nuttx/fs/fs_seekdir.c | 230 |
1 files changed, 0 insertions, 230 deletions
diff --git a/nuttx/fs/fs_seekdir.c b/nuttx/fs/fs_seekdir.c deleted file mode 100644 index 781d35f27..000000000 --- a/nuttx/fs/fs_seekdir.c +++ /dev/null @@ -1,230 +0,0 @@ -/**************************************************************************** - * fs/fs_seekdir.c - * - * Copyright (C) 2007, 2008, 2011 Gregory Nutt. All rights reserved. - * Author: Gregory Nutt <gnutt@nuttx.org> - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in - * the documentation and/or other materials provided with the - * distribution. - * 3. Neither the name NuttX nor the names of its contributors may be - * used to endorse or promote products derived from this software - * without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS - * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT - * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS - * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE - * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, - * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, - * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS - * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED - * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT - * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN - * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE - * POSSIBILITY OF SUCH DAMAGE. - * - ****************************************************************************/ - -/**************************************************************************** - * Included Files - ****************************************************************************/ - -#include <nuttx/config.h> - -#include <sys/types.h> -#include <dirent.h> -#include <errno.h> - -#include <nuttx/fs/fs.h> -#include <nuttx/fs/dirent.h> - -#include "fs_internal.h" - -/**************************************************************************** - * Private Functions - ****************************************************************************/ - -/**************************************************************************** - * Name: seekpseudodir - ****************************************************************************/ - -static inline void seekpseudodir(struct fs_dirent_s *idir, off_t offset) -{ - struct inode *curr; - struct inode *prev; - off_t pos; - - /* Determine a starting point for the seek. If the seek - * is "forward" from the current position, then we will - * start at the current poisition. Otherwise, we will - * "rewind" to the root dir. - */ - - if ( offset < idir->fd_position ) - { - pos = 0; - curr = idir->fd_root; - } - else - { - pos = idir->fd_position; - curr = idir->u.pseudo.fd_next; - } - - /* Traverse the peer list starting at the 'root' of the - * the list until we find the node at 'offset". If devices - * are being registered and unregistered, then this can - * be a very unpredictable operation. - */ - - inode_semtake(); - for (; curr && pos != offset; pos++, curr = curr->i_peer); - - /* Now get the inode to vist next time that readdir() is called */ - - prev = idir->u.pseudo.fd_next; - idir->u.pseudo.fd_next = curr; /* The next node to visit (might be null) */ - idir->fd_position = pos; /* Might be beyond the last dirent */ - - if (curr) - { - /* Increment the reference count on this next node */ - - curr->i_crefs++; - } - - inode_semgive(); - - if (prev) - { - inode_release(prev); - } -} - -/**************************************************************************** - * Name: seekmountptdir - ****************************************************************************/ - -#ifndef CONFIG_DISABLE_MOUNTPOINT -static inline void seekmountptdir(struct fs_dirent_s *idir, off_t offset) -{ - struct inode *inode; - off_t pos; - - /* Determine a starting point for the seek. If the seek - * is "forward" from the current position, then we will - * start at the current poisition. Otherwise, we will - * "rewind" to the root dir. - */ - - inode = idir->fd_root; - if ( offset < idir->fd_position ) - { - if (inode->u.i_mops && inode->u.i_mops->rewinddir) - { - /* Perform the rewinddir() operation */ - - inode->u.i_mops->rewinddir(inode, idir); - pos = 0; - } - else - { - /* We can't do the seek and there is no way to return - * an error indication. - */ - - return; - } - } - else - { - pos = idir->fd_position; - } - - /* This is a brute force approach... we will just read - * directory entries until we are at the desired position. - */ - - while (pos < offset) - { - if (!inode->u.i_mops || !inode->u.i_mops->readdir || - inode->u.i_mops->readdir(inode, idir) < 0) - { - /* We can't read the next entry and there is no way to return - * an error indication. - */ - - return; - } - - /* Increment the position on each successful read */ - - pos++; - } - - /* If we get here the directory position has been successfully set */ - - idir->fd_position = pos; -} -#endif - -/**************************************************************************** - * Public Functions - ****************************************************************************/ - -/**************************************************************************** - * Name: seekdir - * - * Description: - * The seekdir() function sets the location in the directory stream from - * which the next readdir() call will start. seekdir() should be used with - * an offset returned by telldir(). - * - * Inputs: - * dirp -- An instance of type DIR created by a previous - * call to opendir(); - * offset -- offset to seek to - * - * Return: - * None - * - ****************************************************************************/ - -void seekdir(FAR DIR *dirp, off_t offset) -{ - struct fs_dirent_s *idir = (struct fs_dirent_s *)dirp; - - /* Sanity checks */ - - if (!idir || !idir->fd_root) - { - return; - } - - /* The way we handle the readdir depends on the type of inode - * that we are dealing with. - */ - -#ifndef CONFIG_DISABLE_MOUNTPOINT - if (INODE_IS_MOUNTPT(idir->fd_root)) - { - /* The node is a file system mointpoint */ - - seekmountptdir(idir, offset); - } - else -#endif - { - /* The node is part of the root pseudo file system */ - - seekpseudodir(idir, offset); - } -} |