/*
 * Copyright (c) 2006-2023, RT-Thread Development Team
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Change Logs:
 * Date           Author       Notes
 * 2023-11-13     Shell        init ver.
 */

#include "bsd_porting.h"

/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2008 Ed Schouten <ed@FreeBSD.org>
 * All rights reserved.
 *
 * Portions of this software were developed under sponsorship from Snow
 * B.V., the Netherlands.
 *
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS 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.
 */

#ifndef _SYS_TTYQUEUE_H_
#define _SYS_TTYQUEUE_H_

#ifndef __LWP_TERMINAL_H__
#error "can only be included through <teminal.h>"
#endif /* !__LWP_TERMINAL_H__ */

struct lwp_tty;
struct ttyinq_block;
struct ttyoutq_block;
struct uio;

/* Data input queue. */
struct ttyinq
{
    struct ttyinq_block *ti_firstblock;
    struct ttyinq_block *ti_startblock;
    struct ttyinq_block *ti_reprintblock;
    struct ttyinq_block *ti_lastblock;
    unsigned int ti_begin;
    unsigned int ti_linestart;
    unsigned int ti_reprint;
    unsigned int ti_end;
    unsigned int ti_nblocks;
    unsigned int ti_quota;
};
#define TTYINQ_DATASIZE 128

/* Data output queue. */
struct ttyoutq
{
    struct ttyoutq_block *to_firstblock;
    struct ttyoutq_block *to_lastblock;
    unsigned int to_begin;
    unsigned int to_end;
    unsigned int to_nblocks;
    unsigned int to_quota;
};
#define TTYOUTQ_DATASIZE (256 - sizeof(struct ttyoutq_block *))

/* Input queue handling routines. */
int ttyinq_setsize(struct ttyinq *ti, struct lwp_tty *tp, size_t len);
void ttyinq_free(struct ttyinq *ti);
int ttyinq_read_uio(struct ttyinq *ti, struct lwp_tty *tp, struct uio *uio,
                    size_t readlen, size_t flushlen);
size_t ttyinq_write(struct ttyinq *ti, const void *buf, size_t len, int quote);
int ttyinq_write_nofrag(struct ttyinq *ti, const void *buf, size_t len,
                        int quote);
void ttyinq_canonicalize(struct ttyinq *ti);
size_t ttyinq_findchar(struct ttyinq *ti, const char *breakc, size_t maxlen,
                       char *lastc);
void ttyinq_flush(struct ttyinq *ti);
int ttyinq_peekchar(struct ttyinq *ti, char *c, int *quote);
void ttyinq_unputchar(struct ttyinq *ti);
void ttyinq_reprintpos_set(struct ttyinq *ti);
void ttyinq_reprintpos_reset(struct ttyinq *ti);

rt_inline size_t ttyinq_getsize(struct ttyinq *ti)
{
    return (ti->ti_nblocks * TTYINQ_DATASIZE);
}

rt_inline size_t ttyinq_getallocatedsize(struct ttyinq *ti)
{
    return (ti->ti_quota * TTYINQ_DATASIZE);
}

rt_inline size_t ttyinq_bytesleft(struct ttyinq *ti)
{
    size_t len;

    /* Make sure the usage never exceeds the length. */
    len = ti->ti_nblocks * TTYINQ_DATASIZE;
    MPASS(len >= ti->ti_end);

    return (len - ti->ti_end);
}

rt_inline size_t ttyinq_bytescanonicalized(struct ttyinq *ti)
{
    MPASS(ti->ti_begin <= ti->ti_linestart);

    return (ti->ti_linestart - ti->ti_begin);
}

rt_inline size_t ttyinq_bytesline(struct ttyinq *ti)
{
    MPASS(ti->ti_linestart <= ti->ti_end);

    return (ti->ti_end - ti->ti_linestart);
}

/* Input buffer iteration. */
typedef void ttyinq_line_iterator_t(void *data, char c, int flags);
void ttyinq_line_iterate_from_linestart(struct ttyinq *ti,
                                        ttyinq_line_iterator_t *iterator,
                                        void *data);
void ttyinq_line_iterate_from_reprintpos(struct ttyinq *ti,
                                         ttyinq_line_iterator_t *iterator,
                                         void *data);

/* Output queue handling routines. */
void ttyoutq_flush(struct ttyoutq *to);
int ttyoutq_setsize(struct ttyoutq *to, struct lwp_tty *tp, size_t len);
void ttyoutq_free(struct ttyoutq *to);
size_t ttyoutq_read(struct ttyoutq *to, void *buf, size_t len);
int ttyoutq_read_uio(struct ttyoutq *to, struct lwp_tty *tp, struct uio *uio);
size_t ttyoutq_write(struct ttyoutq *to, const void *buf, size_t len);
int ttyoutq_write_nofrag(struct ttyoutq *to, const void *buf, size_t len);

rt_inline size_t ttyoutq_getsize(struct ttyoutq *to)
{
    return (to->to_nblocks * TTYOUTQ_DATASIZE);
}

rt_inline size_t ttyoutq_getallocatedsize(struct ttyoutq *to)
{
    return (to->to_quota * TTYOUTQ_DATASIZE);
}

rt_inline size_t ttyoutq_bytesleft(struct ttyoutq *to)
{
    size_t len;

    /* Make sure the usage never exceeds the length. */
    len = to->to_nblocks * TTYOUTQ_DATASIZE;
    MPASS(len >= to->to_end);

    return (len - to->to_end);
}

rt_inline size_t ttyoutq_bytesused(struct ttyoutq *to)
{
    return (to->to_end - to->to_begin);
}

#endif /* !_SYS_TTYQUEUE_H_ */