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

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

 *

 * \brief System-specific implementation of the \ref __read 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 = "?__read"

extern volatile avr32_usart_t *volatile stdio_usart_base;

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

 *         pointed to by \a buffer.

 *

 * \param handle File handle to read from.

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

 * \param size Number of bytes to read.

 *

 * \return The number of bytes read, \c 0 at the end of the file, or

 *         \c _LLIO_ERROR on failure.

 */

size_t __read(int handle, unsigned char *buffer, size_t size)

{

  int nChars = 0;

  // This implementation only reads from stdin.

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

  if (handle != _LLIO_STDIN)

  {

    return _LLIO_ERROR;

  }

  for (; size > 0; --size)

  {

    int c = usart_getchar(stdio_usart_base);

    if (c < 0)

      break;

    *buffer++ = c;

    ++nChars;

  }

  return nChars;

}

_STD_END