xref: /freebsd/sys/sys/tty.h (revision 95ee2897e98f5d444f26ed2334cc7c439f9c16c6)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2008 Ed Schouten <ed@FreeBSD.org>
5  * All rights reserved.
6  *
7  * Portions of this software were developed under sponsorship from Snow
8  * B.V., the Netherlands.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #ifndef _SYS_TTY_H_
33 #define	_SYS_TTY_H_
34 
35 #include <sys/param.h>
36 #include <sys/queue.h>
37 #include <sys/lock.h>
38 #include <sys/mutex.h>
39 #include <sys/condvar.h>
40 #include <sys/selinfo.h>
41 #include <sys/_termios.h>
42 #include <sys/ttycom.h>
43 #include <sys/ttyqueue.h>
44 
45 struct cdev;
46 struct file;
47 struct pgrp;
48 struct session;
49 struct ucred;
50 
51 struct ttydevsw;
52 
53 /*
54  * Per-TTY structure, containing buffers, etc.
55  *
56  * List of locks
57  * (t)	locked by t_mtx
58  * (l)	locked by tty_list_sx
59  * (c)	const until freeing
60  */
61 struct tty {
62 	struct mtx	*t_mtx;		/* TTY lock. */
63 	struct mtx	t_mtxobj;	/* Per-TTY lock (when not borrowing). */
64 	TAILQ_ENTRY(tty) t_list;	/* (l) TTY list entry. */
65 	int		t_drainwait;	/* (t) TIOCDRAIN timeout seconds. */
66 	unsigned int	t_flags;	/* (t) Terminal option flags. */
67 /* Keep flags in sync with db_show_tty and pstat(8). */
68 #define	TF_NOPREFIX	0x00001	/* Don't prepend "tty" to device name. */
69 #define	TF_INITLOCK	0x00002	/* Create init/lock state devices. */
70 #define	TF_CALLOUT	0x00004	/* Create "cua" devices. */
71 #define	TF_OPENED_IN	0x00008	/* "tty" node is in use. */
72 #define	TF_OPENED_OUT	0x00010	/* "cua" node is in use. */
73 #define	TF_OPENED_CONS	0x00020 /* Device in use as console. */
74 #define	TF_OPENED	(TF_OPENED_IN|TF_OPENED_OUT|TF_OPENED_CONS)
75 #define	TF_GONE		0x00040	/* Device node is gone. */
76 #define	TF_OPENCLOSE	0x00080	/* Device is in open()/close(). */
77 #define	TF_ASYNC	0x00100	/* Asynchronous I/O enabled. */
78 #define	TF_LITERAL	0x00200	/* Accept the next character literally. */
79 #define	TF_HIWAT_IN	0x00400	/* We've reached the input watermark. */
80 #define	TF_HIWAT_OUT	0x00800	/* We've reached the output watermark. */
81 #define	TF_HIWAT	(TF_HIWAT_IN|TF_HIWAT_OUT)
82 #define	TF_STOPPED	0x01000	/* Output flow control - stopped. */
83 #define	TF_EXCLUDE	0x02000	/* Exclusive access. */
84 #define	TF_BYPASS	0x04000	/* Optimized input path. */
85 #define	TF_ZOMBIE	0x08000	/* Modem disconnect received. */
86 #define	TF_HOOK		0x10000	/* TTY has hook attached. */
87 #define	TF_BUSY_IN	0x20000	/* Process busy in read() -- not supported. */
88 #define	TF_BUSY_OUT	0x40000	/* Process busy in write(). */
89 #define	TF_BUSY		(TF_BUSY_IN|TF_BUSY_OUT)
90 	unsigned int	t_revokecnt;	/* (t) revoke() count. */
91 
92 	/* Buffering mechanisms. */
93 	struct ttyinq	t_inq;		/* (t) Input queue. */
94 	size_t		t_inlow;	/* (t) Input low watermark. */
95 	struct ttyoutq	t_outq;		/* (t) Output queue. */
96 	size_t		t_outlow;	/* (t) Output low watermark. */
97 
98 	/* Sleeping mechanisms. */
99 	struct cv	t_inwait;	/* (t) Input wait queue. */
100 	struct cv	t_outwait;	/* (t) Output wait queue. */
101 	struct cv	t_outserwait;	/* (t) Serial output wait queue. */
102 	struct cv	t_bgwait;	/* (t) Background wait queue. */
103 	struct cv	t_dcdwait;	/* (t) Carrier Detect wait queue. */
104 
105 	/* Polling mechanisms. */
106 	struct selinfo	t_inpoll;	/* (t) Input poll queue. */
107 	struct selinfo	t_outpoll;	/* (t) Output poll queue. */
108 	struct sigio	*t_sigio;	/* (t) Asynchronous I/O. */
109 
110 	struct termios	t_termios;	/* (t) I/O processing flags. */
111 	struct winsize	t_winsize;	/* (t) Window size. */
112 	unsigned int	t_column;	/* (t) Current cursor position. */
113 	unsigned int	t_writepos;	/* (t) Where input was interrupted. */
114 	int		t_compatflags;	/* (t) COMPAT_43TTY flags. */
115 
116 	/* Init/lock-state devices. */
117 	struct termios	t_termios_init_in;	/* tty%s.init. */
118 	struct termios	t_termios_lock_in;	/* tty%s.lock. */
119 	struct termios	t_termios_init_out;	/* cua%s.init. */
120 	struct termios	t_termios_lock_out;	/* cua%s.lock. */
121 
122 	struct ttydevsw	*t_devsw;	/* (c) Driver hooks. */
123 	struct ttyhook	*t_hook;	/* (t) Capture/inject hook. */
124 
125 	/* Process signal delivery. */
126 	struct pgrp	*t_pgrp;	/* (t) Foreground process group. */
127 	struct session	*t_session;	/* (t) Associated session. */
128 	unsigned int	t_sessioncnt;	/* (t) Backpointing sessions. */
129 
130 	void		*t_devswsoftc;	/* (c) Soft config, for drivers. */
131 	void		*t_hooksoftc;	/* (t) Soft config, for hooks. */
132 	struct cdev	*t_dev;		/* (c) Primary character device. */
133 
134 	size_t		t_prbufsz;	/* (t) SIGINFO buffer size. */
135 	char		t_prbuf[];	/* (t) SIGINFO buffer. */
136 };
137 
138 /*
139  * Userland version of struct tty, for sysctl kern.ttys
140  */
141 struct xtty {
142 	size_t	xt_size;	/* Structure size. */
143 	size_t	xt_insize;	/* Input queue size. */
144 	size_t	xt_incc;	/* Canonicalized characters. */
145 	size_t	xt_inlc;	/* Input line characters. */
146 	size_t	xt_inlow;	/* Input low watermark. */
147 	size_t	xt_outsize;	/* Output queue size. */
148 	size_t	xt_outcc;	/* Output queue usage. */
149 	size_t	xt_outlow;	/* Output low watermark. */
150 	unsigned int xt_column;	/* Current column position. */
151 	pid_t	xt_pgid;	/* Foreground process group. */
152 	pid_t	xt_sid;		/* Session. */
153 	unsigned int xt_flags;	/* Terminal option flags. */
154 	uint32_t xt_dev;	/* Userland device. XXXKIB truncated */
155 };
156 
157 #ifdef _KERNEL
158 
159 /* Used to distinguish between normal, callout, lock and init devices. */
160 #define	TTYUNIT_INIT		0x1
161 #define	TTYUNIT_LOCK		0x2
162 #define	TTYUNIT_CALLOUT		0x4
163 
164 /* Allocation and deallocation. */
165 struct tty *tty_alloc(struct ttydevsw *tsw, void *softc);
166 struct tty *tty_alloc_mutex(struct ttydevsw *tsw, void *softc, struct mtx *mtx);
167 void	tty_rel_pgrp(struct tty *tp, struct pgrp *pgrp);
168 void	tty_rel_sess(struct tty *tp, struct session *sess);
169 void	tty_rel_gone(struct tty *tp);
170 
171 #define	tty_lock(tp)		mtx_lock((tp)->t_mtx)
172 #define	tty_unlock(tp)		mtx_unlock((tp)->t_mtx)
173 #define	tty_lock_owned(tp)	mtx_owned((tp)->t_mtx)
174 #define	tty_assert_locked(tp)	mtx_assert((tp)->t_mtx, MA_OWNED)
175 #define	tty_getlock(tp)		((tp)->t_mtx)
176 
177 /* XXX Should migrate users to tty_assert_locked! */
178 #define	tty_lock_assert(tp, ma)	mtx_assert((tp)->t_mtx, (ma))
179 
180 /* Device node creation. */
181 int	tty_makedevf(struct tty *tp, struct ucred *cred, int flags,
182     const char *fmt, ...) __printflike(4, 5);
183 #define	TTYMK_CLONING		0x1
184 #define	tty_makedev(tp, cred, fmt, ...) \
185 	(void )tty_makedevf((tp), (cred), 0, (fmt), ## __VA_ARGS__)
186 #define	tty_makealias(tp,fmt,...) \
187 	make_dev_alias((tp)->t_dev, fmt, ## __VA_ARGS__)
188 
189 /* Signalling processes. */
190 void	tty_signal_sessleader(struct tty *tp, int signal);
191 void	tty_signal_pgrp(struct tty *tp, int signal);
192 /* Waking up readers/writers. */
193 int	tty_wait(struct tty *tp, struct cv *cv);
194 int	tty_wait_background(struct tty *tp, struct thread *td, int sig);
195 int	tty_timedwait(struct tty *tp, struct cv *cv, int timo);
196 void	tty_wakeup(struct tty *tp, int flags);
197 
198 /* System messages. */
199 int	tty_checkoutq(struct tty *tp);
200 int	tty_putchar(struct tty *tp, char c);
201 int	tty_putstrn(struct tty *tp, const char *p, size_t n);
202 
203 int	tty_ioctl(struct tty *tp, u_long cmd, void *data, int fflag,
204     struct thread *td);
205 int	tty_ioctl_compat(struct tty *tp, u_long cmd, caddr_t data,
206     int fflag, struct thread *td);
207 void	tty_set_winsize(struct tty *tp, const struct winsize *wsz);
208 void	tty_init_console(struct tty *tp, speed_t speed);
209 void	tty_flush(struct tty *tp, int flags);
210 void	tty_hiwat_in_block(struct tty *tp);
211 void	tty_hiwat_in_unblock(struct tty *tp);
212 dev_t	tty_udev(struct tty *tp);
213 #define	tty_opened(tp)		((tp)->t_flags & TF_OPENED)
214 #define	tty_gone(tp)		((tp)->t_flags & TF_GONE)
215 #define	tty_softc(tp)		((tp)->t_devswsoftc)
216 #define	tty_devname(tp)		devtoname((tp)->t_dev)
217 
218 /* Status line printing. */
219 void	tty_info(struct tty *tp);
220 
221 /* /dev/console selection. */
222 void	ttyconsdev_select(const char *name);
223 
224 /* Pseudo-terminal hooks. */
225 int	pts_alloc(int fflags, struct thread *td, struct file *fp);
226 int	pts_alloc_external(int fd, struct thread *td, struct file *fp,
227     struct cdev *dev, const char *name);
228 
229 /* Drivers and line disciplines also need to call these. */
230 #include <sys/ttydisc.h>
231 #include <sys/ttydevsw.h>
232 #include <sys/ttyhook.h>
233 #endif /* _KERNEL */
234 
235 #endif /* !_SYS_TTY_H_ */
236