#ifndef _LINUX_TTY_H
#define _LINUX_TTY_H

/*
 * 'tty.h' defines some structures used by tty_io.c and some defines.
 */

#ifdef __KERNEL__
#include <linux/fs.h>
#include <linux/termios.h>
#include <linux/tqueue.h>
#include <linux/tty_driver.h>
#include <linux/tty_ldisc.h>

#include <asm/system.h>


/*
 * Note: don't mess with NR_PTYS until you understand the tty minor 
 * number allocation game...
 * (Note: the *_driver.minor_start values 1, 64, 128, 192 are
 * hardcoded at present.)
 */
#define MIN_NR_CONSOLES	1	/* must be at least 1 */
#define MAX_NR_CONSOLES	63	/* serial lines start at 64 */
#define MAX_NR_USER_CONSOLES 63	/* must be root to allocate above this */
		/* Note: the ioctl VT_GETSTATE does not work for
		   consoles 16 and higher (since it returns a short) */
#define NR_PTYS		64
#define NR_LDISCS	16

/*
 * These are set up by the setup-routine at boot-time:
 */

struct screen_info {
	unsigned char  orig_x;
	unsigned char  orig_y;
	unsigned char  unused1[2];
	unsigned short orig_video_page;
	unsigned char  orig_video_mode;
	unsigned char  orig_video_cols;
	unsigned short orig_video_ega_ax;
	unsigned short orig_video_ega_bx;
	unsigned short orig_video_ega_cx;
	unsigned char  orig_video_lines;
	unsigned short orig_video_points;
};

extern struct screen_info screen_info;

#define ORIG_X			(screen_info.orig_x)
#define ORIG_Y			(screen_info.orig_y)
#define ORIG_VIDEO_PAGE		(screen_info.orig_video_page)
#define ORIG_VIDEO_MODE		(screen_info.orig_video_mode)
#define ORIG_VIDEO_COLS 	(screen_info.orig_video_cols)
#define ORIG_VIDEO_EGA_AX	(screen_info.orig_video_ega_ax)
#define ORIG_VIDEO_EGA_BX	(screen_info.orig_video_ega_bx)
#define ORIG_VIDEO_EGA_CX	(screen_info.orig_video_ega_cx)
#define ORIG_VIDEO_LINES	(screen_info.orig_video_lines)
#define ORIG_VIDEO_POINTS       (screen_info.orig_video_points)

#define VIDEO_TYPE_MDA		0x10	/* Monochrome Text Display	*/
#define VIDEO_TYPE_CGA		0x11	/* CGA Display 			*/
#define VIDEO_TYPE_EGAM		0x20	/* EGA/VGA in Monochrome Mode	*/
#define VIDEO_TYPE_EGAC		0x21	/* EGA/VGA in Color Mode	*/

/*
 * This character is the same as _POSIX_VDISABLE: it cannot be used as
 * a c_cc[] character, but indicates that a particular special character
 * isn't in use (eg VINTR has no character etc)
 */
#define __DISABLED_CHAR '\0'

/*
 * This is the flip buffer used for the tty driver.  The buffer is
 * located in the tty structure, and is used as a high speed interface
 * between the tty driver and the tty line discipline.
 */
#define TTY_FLIPBUF_SIZE 512

struct tty_flip_buffer {
	struct tq_struct tqueue;
	unsigned char	char_buf[2*TTY_FLIPBUF_SIZE];
	char		flag_buf[2*TTY_FLIPBUF_SIZE];
	char		*char_buf_ptr;
	unsigned char	*flag_buf_ptr;
	int		count;
	int		buf_num;
};

/*
 * When a break, frame error, or parity error happens, these codes are
 * stuffed into the flags buffer.
 */
#define TTY_NORMAL	0
#define TTY_BREAK	1
#define TTY_FRAME	2
#define TTY_PARITY	3
#define TTY_OVERRUN	4

#define INTR_CHAR(tty) ((tty)->termios->c_cc[VINTR])
#define QUIT_CHAR(tty) ((tty)->termios->c_cc[VQUIT])
#define ERASE_CHAR(tty) ((tty)->termios->c_cc[VERASE])
#define KILL_CHAR(tty) ((tty)->termios->c_cc[VKILL])
#define EOF_CHAR(tty) ((tty)->termios->c_cc[VEOF])
#define TIME_CHAR(tty) ((tty)->termios->c_cc[VTIME])
#define MIN_CHAR(tty) ((tty)->termios->c_cc[VMIN])
#define SWTC_CHAR(tty) ((tty)->termios->c_cc[VSWTC])
#define START_CHAR(tty) ((tty)->termios->c_cc[VSTART])
#define STOP_CHAR(tty) ((tty)->termios->c_cc[VSTOP])
#define SUSP_CHAR(tty) ((tty)->termios->c_cc[VSUSP])
#define EOL_CHAR(tty) ((tty)->termios->c_cc[VEOL])
#define REPRINT_CHAR(tty) ((tty)->termios->c_cc[VREPRINT])
#define DISCARD_CHAR(tty) ((tty)->termios->c_cc[VDISCARD])
#define WERASE_CHAR(tty) ((tty)->termios->c_cc[VWERASE])
#define LNEXT_CHAR(tty)	((tty)->termios->c_cc[VLNEXT])
#define EOL2_CHAR(tty) ((tty)->termios->c_cc[VEOL2])

#define _I_FLAG(tty,f)	((tty)->termios->c_iflag & (f))
#define _O_FLAG(tty,f)	((tty)->termios->c_oflag & (f))
#define _C_FLAG(tty,f)	((tty)->termios->c_cflag & (f))
#define _L_FLAG(tty,f)	((tty)->termios->c_lflag & (f))

#define I_IGNBRK(tty)	_I_FLAG((tty),IGNBRK)
#define I_BRKINT(tty)	_I_FLAG((tty),BRKINT)
#define I_IGNPAR(tty)	_I_FLAG((tty),IGNPAR)
#define I_PARMRK(tty)	_I_FLAG((tty),PARMRK)
#define I_INPCK(tty)	_I_FLAG((tty),INPCK)
#define I_ISTRIP(tty)	_I_FLAG((tty),ISTRIP)
#define I_INLCR(tty)	_I_FLAG((tty),INLCR)
#define I_IGNCR(tty)	_I_FLAG((tty),IGNCR)
#define I_ICRNL(tty)	_I_FLAG((tty),ICRNL)
#define I_IUCLC(tty)	_I_FLAG((tty),IUCLC)
#define I_IXON(tty)	_I_FLAG((tty),IXON)
#define I_IXANY(tty)	_I_FLAG((tty),IXANY)
#define I_IXOFF(tty)	_I_FLAG((tty),IXOFF)
#define I_IMAXBEL(tty)	_I_FLAG((tty),IMAXBEL)

#define O_OPOST(tty)	_O_FLAG((tty),OPOST)
#define O_OLCUC(tty)	_O_FLAG((tty),OLCUC)
#define O_ONLCR(tty)	_O_FLAG((tty),ONLCR)
#define O_OCRNL(tty)	_O_FLAG((tty),OCRNL)
#define O_ONOCR(tty)	_O_FLAG((tty),ONOCR)
#define O_ONLRET(tty)	_O_FLAG((tty),ONLRET)
#define O_OFILL(tty)	_O_FLAG((tty),OFILL)
#define O_OFDEL(tty)	_O_FLAG((tty),OFDEL)
#define O_NLDLY(tty)	_O_FLAG((tty),NLDLY)
#define O_CRDLY(tty)	_O_FLAG((tty),CRDLY)
#define O_TABDLY(tty)	_O_FLAG((tty),TABDLY)
#define O_BSDLY(tty)	_O_FLAG((tty),BSDLY)
#define O_VTDLY(tty)	_O_FLAG((tty),VTDLY)
#define O_FFDLY(tty)	_O_FLAG((tty),FFDLY)

#define C_BAUD(tty)	_C_FLAG((tty),CBAUD)
#define C_CSIZE(tty)	_C_FLAG((tty),CSIZE)
#define C_CSTOPB(tty)	_C_FLAG((tty),CSTOPB)
#define C_CREAD(tty)	_C_FLAG((tty),CREAD)
#define C_PARENB(tty)	_C_FLAG((tty),PARENB)
#define C_PARODD(tty)	_C_FLAG((tty),PARODD)
#define C_HUPCL(tty)	_C_FLAG((tty),HUPCL)
#define C_CLOCAL(tty)	_C_FLAG((tty),CLOCAL)
#define C_CIBAUD(tty)	_C_FLAG((tty),CIBAUD)
#define C_CRTSCTS(tty)	_C_FLAG((tty),CRTSCTS)

#define L_ISIG(tty)	_L_FLAG((tty),ISIG)
#define L_ICANON(tty)	_L_FLAG((tty),ICANON)
#define L_XCASE(tty)	_L_FLAG((tty),XCASE)
#define L_ECHO(tty)	_L_FLAG((tty),ECHO)
#define L_ECHOE(tty)	_L_FLAG((tty),ECHOE)
#define L_ECHOK(tty)	_L_FLAG((tty),ECHOK)
#define L_ECHONL(tty)	_L_FLAG((tty),ECHONL)
#define L_NOFLSH(tty)	_L_FLAG((tty),NOFLSH)
#define L_TOSTOP(tty)	_L_FLAG((tty),TOSTOP)
#define L_ECHOCTL(tty)	_L_FLAG((tty),ECHOCTL)
#define L_ECHOPRT(tty)	_L_FLAG((tty),ECHOPRT)
#define L_ECHOKE(tty)	_L_FLAG((tty),ECHOKE)
#define L_FLUSHO(tty)	_L_FLAG((tty),FLUSHO)
#define L_PENDIN(tty)	_L_FLAG((tty),PENDIN)
#define L_IEXTEN(tty)	_L_FLAG((tty),IEXTEN)

/*
 * Where all of the state associated with a tty is kept while the tty
 * is open.  Since the termios state should be kept even if the tty
 * has been closed --- for things like the baud rate, etc --- it is
 * not stored here, but rather a pointer to the real state is stored
 * here.  Possible the winsize structure should have the same
 * treatment, but (1) the default 80x24 is usually right and (2) it's
 * most often used by a windowing system, which will set the correct
 * size each time the window is created or resized anyway.
 * IMPORTANT: since this structure is dynamically allocated, it must
 * be no larger than 4096 bytes.  Changing TTY_BUF_SIZE will change
 * the size of this structure, and it needs to be done with care.
 * 						- TYT, 9/14/92
 */
struct tty_struct {
	int	magic;
	struct tty_driver driver;
	struct tty_ldisc ldisc;
	struct termios *termios, *termios_locked;
	int pgrp;
	int session;
	dev_t	device;
	unsigned long flags;
	int count;
	struct winsize winsize;
	unsigned char stopped:1, hw_stopped:1, packet:1;
	unsigned char ctrl_status;

	struct tty_struct *link;
	struct fasync_struct *fasync;
	struct tty_flip_buffer flip;
	int max_flip_cnt;
	struct wait_queue *write_wait;
	struct wait_queue *read_wait;
	void *disc_data;
	void *driver_data;

#define N_TTY_BUF_SIZE 4096
	
	/*
	 * The following is data for the N_TTY line discipline.  For
	 * historical reasons, this is included in the tty structure.
	 */
	unsigned int column;
	unsigned char lnext:1, erasing:1, raw:1, real_raw:1, icanon:1;
	unsigned char closing:1;
	unsigned short minimum_to_wake;
	unsigned overrun_time;
	int num_overrun;
	unsigned long process_char_map[256/(8*sizeof(unsigned long))];
	char *read_buf;
	int read_head;
	int read_tail;
	int read_cnt;
	unsigned long read_flags[N_TTY_BUF_SIZE/(8*sizeof(unsigned long))];
	int canon_data;
	unsigned long canon_head;
	unsigned int canon_column;
};

/* tty magic number */
#define TTY_MAGIC		0x5401

/*
 * These bits are used in the flags field of the tty structure.
 * 
 * So that interrupts won't be able to mess up the queues,
 * copy_to_cooked must be atomic with respect to itself, as must
 * tty->write.  Thus, you must use the inline functions set_bit() and
 * clear_bit() to make things atomic.
 */
#define TTY_THROTTLED 0
#define TTY_IO_ERROR 1
#define TTY_SLAVE_CLOSED 2
#define TTY_EXCLUSIVE 3
#define TTY_DEBUG 4
#define TTY_DO_WRITE_WAKEUP 5
#define TTY_PUSH 6
#define TTY_CLOSING 7

#define TTY_WRITE_FLUSH(tty) tty_write_flush((tty))

extern void tty_write_flush(struct tty_struct *);

extern struct termios tty_std_termios;
extern struct tty_struct * redirect;
extern struct tty_ldisc ldiscs[];
extern int fg_console;
extern struct wait_queue * keypress_wait;

/*	intr=^C		quit=^|		erase=del	kill=^U
	eof=^D		vtime=\0	vmin=\1		sxtc=\0
	start=^Q	stop=^S		susp=^Z		eol=\0
	reprint=^R	discard=^U	werase=^W	lnext=^V
	eol2=\0
*/
#define INIT_C_CC "\003\034\177\025\004\0\1\0\021\023\032\0\022\017\027\026\0"

extern long rs_init(long);
extern long lp_init(long);
extern long con_init(long);
extern long pty_init(long);
extern long tty_init(long);
extern long vcs_init(long);
#ifdef CONFIG_CYCLADES
extern long cy_init(long);
#endif

extern int tty_paranoia_check(struct tty_struct *tty, dev_t device,
			      const char *routine);
extern char *_tty_name(struct tty_struct *tty, char *buf);
extern char *tty_name(struct tty_struct *tty);
extern void tty_wait_until_sent(struct tty_struct * tty, int timeout);
extern int tty_check_change(struct tty_struct * tty);
extern void stop_tty(struct tty_struct * tty);
extern void start_tty(struct tty_struct * tty);
extern int tty_register_ldisc(int disc, struct tty_ldisc *new_ldisc);
extern int tty_register_driver(struct tty_driver *driver);
extern int tty_unregister_driver(struct tty_driver *driver);
extern int tty_read_raw_data(struct tty_struct *tty, unsigned char *bufp,
			     int buflen);

extern int is_orphaned_pgrp(int pgrp);
extern int is_ignored(int sig);
extern int tty_signal(int sig, struct tty_struct *tty);
extern void tty_hangup(struct tty_struct * tty);
extern void tty_vhangup(struct tty_struct * tty);
extern void tty_unhangup(struct file *filp);
extern int tty_hung_up_p(struct file * filp);
extern void do_SAK(struct tty_struct *tty);
extern void disassociate_ctty(int priv);

/* n_tty.c */
extern struct tty_ldisc tty_ldisc_N_TTY;

/* tty_ioctl.c */
extern int n_tty_ioctl(struct tty_struct * tty, struct file * file,
		       unsigned int cmd, unsigned long arg);

/* serial.c */

extern int  rs_open(struct tty_struct * tty, struct file * filp);

/* pty.c */

extern int  pty_open(struct tty_struct * tty, struct file * filp);

/* console.c */

extern int con_open(struct tty_struct * tty, struct file * filp);
extern void update_screen(int new_console);

/* vt.c */

extern int vt_ioctl(struct tty_struct *tty, struct file * file,
		    unsigned int cmd, unsigned long arg);

#endif /* __KERNEL__ */
#endif
