Subversion Repositories openrisc_2011-10-31

/*
 *  lseek() - POSIX 1003.1b 6.5.3 - Reposition Read/Write File Offset
 *
 *  COPYRIGHT (c) 1989-1999.
 *  On-Line Applications Research Corporation (OAR).
 *
 *  The license and distribution terms for this file may be
 *  found in the file LICENSE in this distribution or at
 *  http://www.OARcorp.com/rtems/license.html.
 *
 *  $Id: lseek.c,v 1.2 2001-09-27 12:01:15 chris Exp $
 */
 
#include <stdio.h>
 
#include "libio_.h"
 
off_t lseek(
  int     fd,
  off_t   offset,
  int     whence
)
{
  rtems_libio_t *iop;
 
  rtems_libio_check_fd( fd );
  iop = rtems_libio_iop( fd );
  rtems_libio_check_is_open(iop);
 
  /*
   *  Now process the lseek().
   */
 
  switch ( whence ) {
    case SEEK_SET:
      iop->offset = offset;
      break;
 
    case SEEK_CUR:
      iop->offset += offset;
      break;
 
    case SEEK_END:
      iop->offset = iop->size - offset;
      break;
 
    default:
      errno = EINVAL;
      return -1;
  }
 
  if ( !iop->handlers->lseek )
    set_errno_and_return_minus_one( ENOTSUP );
 
  return (*iop->handlers->lseek)( iop, offset, whence );
}
 
/*
 *  _lseek_r
 *
 *  This is the Newlib dependent reentrant version of lseek().
 */
 
#if defined(RTEMS_NEWLIB)
 
#include <reent.h>
 
off_t _lseek_r( 
  struct _reent *ptr,
  int            fd,
  off_t          offset,
  int            whence
)
{
  return lseek( fd, offset, whence );
}
#endif