/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 1997 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/*        All Rights Reserved   */

/* LINTLIBRARY */


#include        <errno.h>
#include        <fcntl.h>
#include        <stdio.h>
#include        "lp.h"
#include        "msgs.h"

static  fifobuffer_t    **FifoBufferTable       = NULL;
static  int             FifoBufferTableSize     = 0;

/*
**      Local functions
*/
static  int             InitFifoBufferTable (void);
static  int             GrowFifoBufferTable (int);
static  fifobuffer_t    *NewFifoBuffer (int);


int
ResetFifoBuffer(int fd)
{
        if ((!FifoBufferTableSize) && (InitFifoBufferTable () < 0))
                return  -1;

        if (fd >= FifoBufferTableSize)
                return  0;

        if (FifoBufferTable [fd]) {
                FifoBufferTable [fd]->full = 0;
                FifoBufferTable [fd]->psave =
                FifoBufferTable [fd]->psave_end =
                        FifoBufferTable [fd]->save;
        }
        return  0;
}


fifobuffer_t *
GetFifoBuffer(int fd)
{
        if (fd < 0) {
                errno = EINVAL;
                return  NULL;
        }
        if ((fd >= FifoBufferTableSize) && (GrowFifoBufferTable (fd) < 0))
                return  NULL;

        if (!FifoBufferTable [fd]) {
                if (!NewFifoBuffer (fd))
                        return  NULL;

                FifoBufferTable [fd]->full = 0;
                FifoBufferTable [fd]->psave =
                FifoBufferTable [fd]->psave_end =
                        FifoBufferTable [fd]->save;
        }

        return  FifoBufferTable [fd];
}


static  int
InitFifoBufferTable()
{
        if (FifoBufferTableSize)
                return  0;

        FifoBufferTable = (fifobuffer_t **)
                Calloc (100, sizeof (fifobuffer_t *));
        if (!FifoBufferTable)
                return  -1;     /* ENOMEM is already set. */

        FifoBufferTableSize = 100;

        return  0;
}


static int
GrowFifoBufferTable (int fd)
{
        fifobuffer_t    **newpp;

        newpp = (fifobuffer_t **)
                Realloc ((void*)FifoBufferTable,
                (fd+10)*sizeof (fifobuffer_t *));
        if (!newpp)
                return  -1;     /* ENOMEM is already set. */

        FifoBufferTableSize = fd+10;

        return  0;
}


static fifobuffer_t *
NewFifoBuffer(int fd)
{
        int     i;

        for (i=0; i < FifoBufferTableSize; i++)
        {
                if (FifoBufferTable [i] &&
                    Fcntl (i, F_GETFL) < 0 &&
                    errno == EBADF)
                {
                        FifoBufferTable [fd] = FifoBufferTable [i];
                        FifoBufferTable [i] = NULL;
                        return  FifoBufferTable [fd];
                }
        }
        FifoBufferTable [fd] = (fifobuffer_t *)
                Calloc (1, sizeof (fifobuffer_t));

        return  FifoBufferTable [fd];
}