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//========================================================================

//

//      fread.cxx

//

//      ANSI Stdio fread() function

//

//========================================================================

//####ECOSGPLCOPYRIGHTBEGIN####

// -------------------------------------------

// This file is part of eCos, the Embedded Configurable Operating System.

// Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.

//

// eCos is free software; you can redistribute it and/or modify it under

// the terms of the GNU General Public License as published by the Free

// Software Foundation; either version 2 or (at your option) any later version.

//

// eCos is distributed in the hope that it will be useful, but WITHOUT ANY

// WARRANTY; without even the implied warranty of MERCHANTABILITY or

// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

// for more details.

//

// You should have received a copy of the GNU General Public License along

// with eCos; if not, write to the Free Software Foundation, Inc.,

// 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.

//

// As a special exception, if other files instantiate templates or use macros

// or inline functions from this file, or you compile this file and link it

// with other works to produce a work based on this file, this file does not

// by itself cause the resulting work to be covered by the GNU General Public

// License. However the source code for this file must still be made available

// in accordance with section (3) of the GNU General Public License.

//

// This exception does not invalidate any other reasons why a work based on

// this file might be covered by the GNU General Public License.

//

// Alternative licenses for eCos may be arranged by contacting Red Hat, Inc.

// at http://sources.redhat.com/ecos/ecos-license/

// -------------------------------------------

//####ECOSGPLCOPYRIGHTEND####

//========================================================================

//#####DESCRIPTIONBEGIN####

//

// Author(s):     jlarmour

// Contributors:  

// Date:          2000-04-20

// Purpose:     

// Description: 

// Usage:       

//

//####DESCRIPTIONEND####

//

//=======================================================================

// CONFIGURATION

#include <pkgconf/libc_stdio.h>   // Configuration header

// INCLUDES

#include <cyg/infra/cyg_type.h>     // Common project-wide type definitions

#include <cyg/infra/cyg_ass.h>      // Assertion support

#include <cyg/infra/cyg_trac.h>     // Tracing support

#include <stddef.h>                 // NULL and size_t from compiler

#include <stdio.h>                  // header for this file

#include <errno.h>                  // error codes

#include <cyg/libc/stdio/stream.hxx>// Cyg_StdioStream

// FUNCTIONS

externC size_t

fread( void *ptr, size_t object_size, size_t num_objects, FILE *stream )

{

    Cyg_StdioStream *real_stream = (Cyg_StdioStream *)stream;

    cyg_ucount32 bytes_read;

    cyg_ucount32 bytes_to_read;

    cyg_ucount32 total_read;

    Cyg_ErrNo err;

    cyg_uint8 *ptrc = (cyg_uint8 *)ptr;

    CYG_REPORT_FUNCNAMETYPE( "fread", "read %d objects" );

    CYG_REPORT_FUNCARG4( "ptr=%08x, object_size=%d, num_objects=%d, "

                         "stream=%08x", ptr, object_size, num_objects,

                         stream );

    bytes_to_read = object_size*num_objects;

    total_read = 0;

    if ( !bytes_to_read ) {

        CYG_REPORT_RETVAL(0);

        return 0;

    } // if

    err = real_stream->read( (cyg_uint8 *)ptr, bytes_to_read,

                             &bytes_read );

    bytes_to_read -= bytes_read;

    total_read += bytes_read;

    ptrc += bytes_read;

    while (!err && bytes_to_read) { // if no err, but not finished - get next

        err = real_stream->refill_read_buffer();

        if ( !err ) {

            err = real_stream->read( (cyg_uint8 *)ptrc, bytes_to_read,

                                     &bytes_read );

            bytes_to_read -= bytes_read;

            total_read += bytes_read;

            ptrc += bytes_read;

        } // if

    } // while

    if (err) {

        real_stream->set_error( err );

        errno = err;

    } // if

    // we return the number of _objects_ read. Simple division is

    // sufficient as this returns the quotient rather than rounding

    CYG_REPORT_RETVAL( bytes_read/object_size );

    return total_read/object_size;

} // fread()

// EOF fread.cxx