diff options
Diffstat (limited to 'nuttx/fs/fs_lseek.c')
-rw-r--r-- | nuttx/fs/fs_lseek.c | 176 |
1 files changed, 0 insertions, 176 deletions
diff --git a/nuttx/fs/fs_lseek.c b/nuttx/fs/fs_lseek.c deleted file mode 100644 index c57658434..000000000 --- a/nuttx/fs/fs_lseek.c +++ /dev/null @@ -1,176 +0,0 @@ -/**************************************************************************** - * fs/fs_lseek.c - * - * Copyright (C) 2008 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 <unistd.h> -#include <sched.h> -#include <errno.h> - -#include "fs_internal.h" - -#if CONFIG_NFILE_DESCRIPTORS > 0 - -/**************************************************************************** - * Global Functions - ****************************************************************************/ - -/**************************************************************************** - * Name: lseek - * - * Description: - * The lseek() function repositions the offset of the open file associated - * with the file descriptor fildes to the argument 'offset' according to the - * directive 'whence' as follows: - * - * SEEK_SET - * The offset is set to offset bytes. - * SEEK_CUR - * The offset is set to its current location plus offset bytes. - * SEEK_END - * The offset is set to the size of the file plus offset bytes. - * - * The lseek() function allows the file offset to be set beyond the end of the - * file (but this does not change the size of the file). If data is later written - * at this point, subsequent reads of the data in the gap (a "hole") return null - * bytes ('\0') until data is actually written into the gap. - * - * Parameters: - * fd File descriptor of device - * offset Defines the offset to position to - * whence Defines how to use offset - * - * Return: - * The resulting offset on success. -1 on failure withi errno set properly: - * - * EBADF fildes is not an open file descriptor. - * EINVAL whence is not one of SEEK_SET, SEEK_CUR, SEEK_END; or the - * resulting file offset would be negative, or beyond the end of a - * seekable device. - * EOVERFLOW The resulting file offset cannot be represented in an off_t. - * ESPIPE fildes is associated with a pipe, socket, or FIFO. - * - ****************************************************************************/ - -off_t lseek(int fd, off_t offset, int whence) -{ - FAR struct filelist *list; - FAR struct file *filep; - FAR struct inode *inode; - int err; - - /* Did we get a valid file descriptor? */ - - if ((unsigned int)fd >= CONFIG_NFILE_DESCRIPTORS) - { - err = EBADF; - goto errout; - } - - /* Get the thread-specific file list */ - - list = sched_getfiles(); - if (!list) - { - err = EMFILE; - goto errout; - } - - /* Is a driver registered? */ - - filep = &list->fl_files[fd]; - inode = filep->f_inode; - - if (inode && inode->u.i_ops) - { - /* Does it support the seek method */ - - if (inode->u.i_ops->seek) - { - /* Yes, then let it perform the seek */ - - err = (int)inode->u.i_ops->seek(filep, offset, whence); - if (err < 0) - { - err = -err; - goto errout; - } - } - else - { - /* No... there are a couple of default actions we can take */ - - switch (whence) - { - case SEEK_CUR: - offset += filep->f_pos; - - case SEEK_SET: - if (offset >= 0) - { - filep->f_pos = offset; /* Might be beyond the end-of-file */ - break; - } - else - { - err = EINVAL; - goto errout; - } - break; - - case SEEK_END: - err = ENOSYS; - goto errout; - - default: - err = EINVAL; - goto errout; - } - } - } - - return filep->f_pos; - -errout: - set_errno(err); - return (off_t)ERROR; -} - -#endif |