Subversion Repositories openrisc_2011-10-31

/*

 *  read() - POSIX 1003.1b 6.4.1 - Read From a File

 *

 *  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: read.c,v 1.2 2001-09-27 12:01:15 chris Exp $

 */

#include "libio_.h"

ssize_t read(

  int         fd,

  void       *buffer,

  size_t      count

)

{

  int             rc;  /* XXX change to a size_t when prototype is fixed */

  rtems_libio_t *iop;

  rtems_libio_check_fd( fd );

  iop = rtems_libio_iop( fd );

  rtems_libio_check_is_open(iop);

  rtems_libio_check_buffer( buffer );

  rtems_libio_check_count( count );

  rtems_libio_check_permissions( iop, LIBIO_FLAGS_READ );

  /*

   *  Now process the read().

   */

  if ( !iop->handlers->read )

    set_errno_and_return_minus_one( ENOTSUP );

  rc = (*iop->handlers->read)( iop, buffer, count );

  if ( rc > 0 )

    iop->offset += rc;

  return rc;

}

/*

 *  _read_r

 *

 *  This is the Newlib dependent reentrant version of read().

 */

#if defined(RTEMS_NEWLIB)

#include <reent.h>

_ssize_t _read_r(

  struct _reent *ptr,

  int            fd,

  void          *buf,

  size_t         nbytes

)

{

  return read( fd, buf, nbytes );

}

#endif