/*
 * Copyright (c) 2000-2018 Apple Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 *
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 *
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 *
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
/* Copyright (c) 1997 Apple Computer, Inc. All Rights Reserved */
/*-
 * Copyright (c) 1982, 1986, 1993
 *	The Regents of the University of California.  All rights reserved.
 * (c) UNIX System Laboratories, Inc.
 * All or some portions of this file are derived from material licensed
 * to the University of California by American Telephone and Telegraph
 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
 * the permission of UNIX System Laboratories, Inc.
 *
 * 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
 *
 *	@(#)tty.h	8.6 (Berkeley) 1/21/94
 */

#ifndef _SYS_TTY_H_
#define _SYS_TTY_H_

#include <sys/appleapiopts.h>
#include <sys/cdefs.h>
#include <sys/termios.h>
#include <sys/select.h>         /* For struct selinfo. */
#if XNU_KERNEL_PRIVATE
#include <os/refcnt.h>
#endif

#ifdef KERNEL

__BEGIN_DECLS
#include <kern/locks.h>
__END_DECLS

/*
 * NetBSD Clists are actually ring buffers. The c_cc, c_cf, c_cl fields have
 * exactly the same behaviour as in true clists.
 * if c_cq is NULL, the ring buffer has no TTY_QUOTE functionality
 * (but, saves memory and cpu time)
 *
 * *DON'T* play with c_cs, c_ce, c_cq, or c_cl outside tty_subr.c!!!
 */
struct clist {
	int     c_cc;           /* count of characters in queue */
	int     c_cn;           /* total ring buffer length */
	u_char  *c_cf;          /* points to first character */
	u_char  *c_cl;          /* points to next open character */
	u_char  *c_cs;          /* start of ring buffer */
	u_char  *c_ce;          /* c_ce + c_len */
	u_char  *c_cq;          /* N bits/bytes long, see tty_subr.c */
};

#ifndef TTYCLSIZE
#define TTYCLSIZE 1024
#endif

/*
 * Per-tty structure.
 *
 * Should be split in two, into device and tty drivers.
 * Glue could be masks of what to echo and circular buffer
 * (low, high, timeout).
 */
struct tty {
	lck_mtx_t       t_lock;         /* Per tty lock */

	struct  clist t_rawq;           /* Device raw input queue. */
	long    t_rawcc;                /* Raw input queue statistics. */
	struct  clist t_canq;           /* Device canonical queue. */
	long    t_cancc;                /* Canonical queue statistics. */
	struct  clist t_outq;           /* Device output queue. */
	long    t_outcc;                /* Output queue statistics. */
	int     t_line;                 /* Interface to device drivers. */
	dev_t   t_dev;                  /* Device. */
	int     t_state;                /* Device and driver (TS*) state. */
	int     t_flags;                /* Tty flags. */
	int     t_timeout;              /* Timeout for ttywait() */
	struct  pgrp *t_pgrp;           /* (TTYL+LL) Foreground process group. */
	struct  session *t_session;     /* (TTYL+LL) Enclosing session. */
	struct  selinfo t_rsel;         /* Tty read/oob select. */
	struct  selinfo t_wsel;         /* Tty write select. */
	struct  termios t_termios;      /* Termios state. */
	struct  winsize t_winsize;      /* Window size. */
	                                /* Start output. */
	void    (*t_oproc)(struct tty *);
	/* Stop output. */
	void    (*t_stop)(struct tty *, int);
	/* Set hardware state. */
	int     (*t_param)(struct tty *, struct termios *);
	void    *t_sc;                  /* XXX: net/if_sl.c:sl_softc. */
	int     t_column;               /* Tty output column. */
	int     t_rocount, t_rocol;     /* Tty. */
	int     t_hiwat;                /* High water mark. */
	int     t_lowat;                /* Low water mark. */
	int     t_gen;                  /* Generation number. */
	void    *t_iokit;               /* IOKit management */
#if XNU_KERNEL_PRIVATE
	os_ref_atomic_t t_refcnt;
#else
	int     t_refcnt;               /* reference count */
#endif
	thread_t t_locked_thread;       /* thread that owns the lock */
};

#define TTY_NULL (struct tty *)NULL

#define t_cc            t_termios.c_cc
#define t_cflag         t_termios.c_cflag
#define t_iflag         t_termios.c_iflag
#define t_ispeed        t_termios.c_ispeed
#define t_lflag         t_termios.c_lflag
#define t_min           t_termios.c_min
#define t_oflag         t_termios.c_oflag
#define t_ospeed        t_termios.c_ospeed
#define t_time          t_termios.c_time


#define TTIPRI  25                      /* Sleep priority for tty reads. */
#define TTOPRI  26                      /* Sleep priority for tty writes. */

/*
 * User data unfortunately has to be copied through buffers on the way to
 * and from clists.  The buffers are on the stack so their sizes must be
 * fairly small.
 */
#define IBUFSIZ 384                     /* Should be >= max value of MIN. */
#define OBUFSIZ 100

#ifndef TTYHOG
#define TTYHOG  1024
#endif

#define TTMAXHIWAT      roundup(2048, CBSIZE)
#define TTMINHIWAT      roundup(100, CBSIZE)
#define TTMAXLOWAT      256
#define TTMINLOWAT      32
#else
struct tty;
struct clist;
#endif /* KERNEL */

/* These flags are kept in t_state. */
#define TS_SO_OLOWAT    0x00001         /* Wake up when output <= low water. */
#define TS_ASYNC        0x00002         /* Tty in async I/O mode. */
#define TS_BUSY         0x00004         /* Draining output. */
#define TS_CARR_ON      0x00008         /* Carrier is present. */
#define TS_FLUSH        0x00010         /* Outq has been flushed during DMA. */
#define TS_ISOPEN       0x00020         /* Open has completed. */
#define TS_TBLOCK       0x00040         /* Further input blocked. */
#define TS_TIMEOUT      0x00080         /* Wait for output char processing. */
#define TS_TTSTOP       0x00100         /* Output paused. */
#ifdef notyet
#define TS_WOPEN        0x00200         /* Open in progress. */
#endif
#define TS_XCLUDE       0x00400         /* Tty requires exclusivity. */

/* State for intra-line fancy editing work. */
#define TS_BKSL         0x00800         /* State for lowercase \ work. */
#define TS_CNTTB        0x01000         /* Counting tab width, ignore FLUSHO. */
#define TS_ERASE        0x02000         /* Within a \.../ for PRTRUB. */
#define TS_LNCH         0x04000         /* Next character is literal. */
#define TS_TYPEN        0x08000         /* Retyping suspended input (PENDIN). */
#define TS_LOCAL        (TS_BKSL | TS_CNTTB | TS_ERASE | TS_LNCH | TS_TYPEN)

/* Extras. */
#define TS_CAN_BYPASS_L_RINT 0x010000   /* Device in "raw" mode. */
#define TS_CONNECTED    0x020000        /* Connection open. */
#define TS_SNOOP        0x040000        /* Device is being snooped on. */
#define TS_SO_OCOMPLETE 0x080000        /* Wake up when output completes. */
#define TS_ZOMBIE       0x100000        /* Connection lost. */

/* Hardware flow-control-invoked bits. */
#define TS_CAR_OFLOW    0x200000        /* For MDMBUF (XXX handle in driver). */
#ifdef notyet
#define TS_CTS_OFLOW    0x400000        /* For CCTS_OFLOW. */
#define TS_DSR_OFLOW    0x800000        /* For CDSR_OFLOW. */
#endif

#define TS_IOCTL_NOT_OK 0x1000000       /* Workaround <rdar://....> */
#define TS_REVOKE       0x2000000       /* Terminal getting revoked */


/* Character type information. */
#define ORDINARY        0
#define CONTROL         1
#define BACKSPACE       2
#define NEWLINE         3
#define TAB             4
#define VTAB            5
#define RETURN          6

struct speedtab {
	int sp_speed;
	int sp_code;
};

/* Modem control commands (driver). */
#define DMSET           0
#define DMBIS           1
#define DMBIC           2
#define DMGET           3

/* Flags on a character passed to ttyinput. */
#define TTY_CHARMASK    0x000000ff      /* Character mask */
#define TTY_QUOTE       0x00000100      /* Character quoted */
#define TTY_ERRORMASK   0xff000000      /* Error mask */
#define TTY_FE          0x01000000      /* Framing error */
#define TTY_PE          0x02000000      /* Parity error */
#define TTY_OE          0x04000000      /* Overrun error */
#define TTY_BI          0x08000000      /* Break condition */

#ifdef KERNEL

/* Unique sleep addresses. */
#define TSA_CARR_ON(tp)         ((void *)&(tp)->t_rawq)
#define TSA_HUP_OR_INPUT(tp)    ((void *)&(tp)->t_rawq.c_cf)
#define TSA_OCOMPLETE(tp)       ((void *)&(tp)->t_outq.c_cl)
#define TSA_OLOWAT(tp)          ((void *)&(tp)->t_outq)
#define TSA_PTC_READ(tp)        ((void *)&(tp)->t_outq.c_cf)
#define TSA_PTC_WRITE(tp)       ((void *)&(tp)->t_rawq.c_cl)
#define TSA_PTS_READ(tp)        ((void *)&(tp)->t_canq)


__BEGIN_DECLS

int      b_to_q(const u_char *cp, int cc, struct clist *q);
void     catq(struct clist *from, struct clist *to);
void     clist_init(void);
int      getc(struct clist *q);
void     ndflush(struct clist *q, int cc);
int      ndqb(struct clist *q, int flag);
u_char  *firstc(struct clist *clp, int *c);
u_char  *nextc(struct clist *q, u_char *cp, int *c);
int      putc(int c, struct clist *q);
int      q_to_b(struct clist *q, u_char *cp, int cc);
int      unputc(struct clist *q);
int      clalloc(struct clist *clp, int size, int quot);
void     clfree(struct clist *clp);
void    cinit(void);
void    clrbits(u_char *cp, int off, int len);

#ifdef KERNEL_PRIVATE
void    tty_init(void);
/*
 * The locked version of this function is used from routines which hold
 * the tty_lock(), such as ttcompat() in tty_compat.c
 */
int     ttioctl_locked(struct tty *tp, u_long com, caddr_t data, int flag,
    struct proc *p);

int     ttcompat(struct tty *tp, u_long com, caddr_t data, int flag,
    struct proc *p);
#endif /* KERNEL_PRIVATE */

void tty_lock(struct tty *tp);
bool tty_trylock(struct tty *tp);
void tty_unlock(struct tty *tp);
bool tty_islocked(struct tty *tp);

void     termioschars(struct termios *t);
int      tputchar(int c, struct tty *tp);
int      ttioctl(struct tty *tp, u_long com, caddr_t data, int flag,
    struct proc *p);
int      ttread(struct tty *tp, struct uio *uio, int flag);
int      ttyselect(struct tty *tp, int rw, void * wql, struct proc *p);
int      ttselect(dev_t dev, int rw, void * wql, struct proc *p);
void     ttsetwater(struct tty *tp);
int      ttspeedtab(int speed, struct speedtab *table);
int      ttstart(struct tty *tp);
void     ttwakeup(struct tty *tp);
int      ttwrite(struct tty *tp, struct uio *uio, int flag);
void     ttwwakeup(struct tty *tp);
void     ttyblock(struct tty *tp);
int      ttycheckoutq(struct tty *tp, int wait);
int      ttyclose(struct tty *tp);      /* LEGACY: avoid using */
void     ttyflush(struct tty *tp, int rw);
void     ttyinfo(struct tty *tp);
void     ttyinfo_locked(struct tty *tp);
int      ttyinput(int c, struct tty *tp);
int      ttylclose(struct tty *tp, int flag);
int      ttymodem(struct tty *tp, int flag);
int      ttyopen(dev_t device, struct tty *tp);
int      ttysleep(struct tty *tp,
    void *chan, int pri, const char *wmesg, int timeout);
int      ttywait(struct tty *tp);
struct tty *ttymalloc(void);
void     ttyfree(struct tty *);
void     ttyfree_locked(struct tty *);

#ifdef XNU_KERNEL_PRIVATE
extern void ttyhold(struct tty *tp);

#define TTY_LOCK_OWNED(tp) LCK_MTX_ASSERT(&tp->t_lock, LCK_MTX_ASSERT_OWNED)
#define TTY_LOCK_NOTOWNED(tp) LCK_MTX_ASSERT(&tp->t_lock, LCK_MTX_ASSERT_NOTOWNED)

#define PTS_MAJOR 4
#define PTC_MAJOR 5
#endif /* defined(XNU_KERNEL_PRIVATE) */

__END_DECLS

#endif /* KERNEL */

#endif /* !_SYS_TTY_H_ */
