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

//

//      io/common/io_file.c

//

//      High-level file I/O support.

//

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

//####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):    gthomas

// Contributors: gthomas

// Date:         2000-01-10

// Purpose:      

// Description:  

//              

//

//####DESCRIPTIONEND####

//

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

// File I/O support

#include <pkgconf/io.h>

#include <cyg/io/file.h>

#include <cyg/error/codes.h>

struct file fds[CYGPKG_IO_NFILE];

//

// This function allcates a file "slot".

//

int

falloc(struct file **fp, int *fd)

{

    int i;

    struct file *f;

    f = &fds[0];

    for (i = 0;  i < CYGPKG_IO_NFILE;  i++, f++) {

        if (f->f_flag == 0) {

            f->f_flag = FALLOC;

            *fp = f;

            *fd = i;

            return 0;

        }

    }

    return EMFILE;  // No more files

}

//

// This function is used to return a file slot.

//

void

ffree(struct file *fp)

{

    fp->f_flag = 0;  // Mark free

}

//

// This function provides the mapping from a file descriptor (small

// integer used by application code) to the corresponding file slot.

cyg_bool

getfp(int fd, struct file **fp)

{

    struct file *f;

    if (fd >= CYGPKG_IO_NFILE)

        return -1;

    f =  &fds[fd];

    if (f->f_flag == 0)

        return -1;

    *fp = f;

    return 0;

}