source: rtems/cpukit/libcsupport/src/lseek.c

/* SPDX-License-Identifier: BSD-2-Clause */

/**
 * @file
 * @brief lseek() - POSIX 1003.1b 6.5.3 - Reposition Read/Write File Offset
 */

/*
 *  COPYRIGHT (c) 1989-1999.
 *  On-Line Applications Research Corporation (OAR).
 *
 * 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.
 *
 * 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.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <unistd.h>

#include <rtems/libio_.h>

off_t lseek( int fd, off_t offset, int whence )
{
  rtems_libio_t *iop;
  off_t          rv;

  LIBIO_GET_IOP( fd, iop );

  rv = (*iop->pathinfo.handlers->lseek_h)( iop, offset, whence );
  rtems_libio_iop_drop( iop );
  return rv;
}

/*
 *  _lseek_r
 *
 *  This is the Newlib dependent reentrant version of lseek().
 */

#if defined(RTEMS_NEWLIB) && !defined(HAVE__LSEEK_R)

#include <reent.h>

off_t _lseek_r(
  struct _reent *ptr RTEMS_UNUSED,
  int            fd,
  off_t          offset,
  int            whence
)
{
  return lseek( fd, offset, whence );
}
#endif