Subversion Repositories openrisc_2011-10-31

/*This file is prepared for Doxygen automatic documentation generation.*/

/*! \file *********************************************************************

 *

 * \brief System-specific implementation of the \ref __write function used by

          the standard library.

 *

 * - Compiler:           IAR EWAVR32

 * - Supported devices:  All AVR32 devices with a USART module can be used.

 * - AppNote:

 *

 * \author               Atmel Corporation: http://www.atmel.com \n

 *                       Support and FAQ: http://support.atmel.no/

 *

 ******************************************************************************/

/* Copyright (c) 2007, Atmel Corporation All rights reserved.

 *

 * 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. The name of ATMEL may not be used to endorse or promote products derived

 * from this software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY ATMEL ``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 EXPRESSLY AND

 * SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL 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.

 */

#include <yfuns.h>

#include <avr32/io.h>

#include "usart.h"

_STD_BEGIN

#pragma module_name = "?__write"

//! Pointer to the base of the USART module instance to use for stdio.

__no_init volatile avr32_usart_t *volatile stdio_usart_base;

/*! \brief Writes a number of bytes, at most \a size, from the memory area

 *         pointed to by \a buffer.

 *

 * If \a buffer is zero then \ref __write performs flushing of internal buffers,

 * if any. In this case, \a handle can be \c -1 to indicate that all handles

 * should be flushed.

 *

 * \param handle File handle to write to.

 * \param buffer Pointer to buffer to read bytes to write from.

 * \param size Number of bytes to write.

 *

 * \return The number of bytes written, or \c _LLIO_ERROR on failure.

 */

size_t __write(int handle, const unsigned char *buffer, size_t size)

{

  size_t nChars = 0;

  if (buffer == 0)

  {

    // This means that we should flush internal buffers.

    return 0;

  }

  // This implementation only writes to stdout and stderr.

  // For all other file handles, it returns failure.

  if (handle != _LLIO_STDOUT && handle != _LLIO_STDERR)

  {

    return _LLIO_ERROR;

  }

  for (; size != 0; --size)

  {

    if (usart_putchar(stdio_usart_base, *buffer++) < 0)

    {

      return _LLIO_ERROR;

    }

    ++nChars;

  }

  return nChars;

}

_STD_END