1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2008 Ed Schouten <ed@FreeBSD.org>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #ifndef _SYS_TTYHOOK_H_
30 #define _SYS_TTYHOOK_H_
31
32 #ifndef _SYS_TTY_H_
33 #error "can only be included through <sys/tty.h>"
34 #endif /* !_SYS_TTY_H_ */
35
36 struct tty;
37
38 /*
39 * Hooks interface, which allows to capture and inject traffic into the
40 * input and output paths of a TTY.
41 */
42
43 typedef int th_rint_t(struct tty *tp, char c, int flags);
44 typedef size_t th_rint_bypass_t(struct tty *tp, const void *buf, size_t len);
45 typedef void th_rint_done_t(struct tty *tp);
46 typedef size_t th_rint_poll_t(struct tty *tp);
47
48 typedef size_t th_getc_inject_t(struct tty *tp, void *buf, size_t len);
49 typedef void th_getc_capture_t(struct tty *tp, const void *buf, size_t len);
50 typedef size_t th_getc_poll_t(struct tty *tp);
51
52 typedef void th_close_t(struct tty *tp);
53
54 struct ttyhook {
55 /* Character input. */
56 th_rint_t *th_rint;
57 th_rint_bypass_t *th_rint_bypass;
58 th_rint_done_t *th_rint_done;
59 th_rint_poll_t *th_rint_poll;
60
61 /* Character output. */
62 th_getc_inject_t *th_getc_inject;
63 th_getc_capture_t *th_getc_capture;
64 th_getc_poll_t *th_getc_poll;
65
66 th_close_t *th_close;
67 };
68
69 int ttyhook_register(struct tty **, struct proc *, int,
70 struct ttyhook *, void *);
71 void ttyhook_unregister(struct tty *);
72 #define ttyhook_softc(tp) ((tp)->t_hooksoftc)
73 #define ttyhook_hashook(tp,hook) ((tp)->t_hook != NULL && \
74 (tp)->t_hook->th_ ## hook != NULL)
75
76 static __inline int
ttyhook_rint(struct tty * tp,char c,int flags)77 ttyhook_rint(struct tty *tp, char c, int flags)
78 {
79 tty_assert_locked(tp);
80 MPASS(!tty_gone(tp));
81
82 return tp->t_hook->th_rint(tp, c, flags);
83 }
84
85 static __inline size_t
ttyhook_rint_bypass(struct tty * tp,const void * buf,size_t len)86 ttyhook_rint_bypass(struct tty *tp, const void *buf, size_t len)
87 {
88 tty_assert_locked(tp);
89 MPASS(!tty_gone(tp));
90
91 return tp->t_hook->th_rint_bypass(tp, buf, len);
92 }
93
94 static __inline void
ttyhook_rint_done(struct tty * tp)95 ttyhook_rint_done(struct tty *tp)
96 {
97 tty_assert_locked(tp);
98 MPASS(!tty_gone(tp));
99
100 tp->t_hook->th_rint_done(tp);
101 }
102
103 static __inline size_t
ttyhook_rint_poll(struct tty * tp)104 ttyhook_rint_poll(struct tty *tp)
105 {
106 tty_assert_locked(tp);
107 MPASS(!tty_gone(tp));
108
109 return tp->t_hook->th_rint_poll(tp);
110 }
111
112 static __inline size_t
ttyhook_getc_inject(struct tty * tp,void * buf,size_t len)113 ttyhook_getc_inject(struct tty *tp, void *buf, size_t len)
114 {
115 tty_assert_locked(tp);
116 MPASS(!tty_gone(tp));
117
118 return tp->t_hook->th_getc_inject(tp, buf, len);
119 }
120
121 static __inline void
ttyhook_getc_capture(struct tty * tp,const void * buf,size_t len)122 ttyhook_getc_capture(struct tty *tp, const void *buf, size_t len)
123 {
124 tty_assert_locked(tp);
125 MPASS(!tty_gone(tp));
126
127 tp->t_hook->th_getc_capture(tp, buf, len);
128 }
129
130 static __inline size_t
ttyhook_getc_poll(struct tty * tp)131 ttyhook_getc_poll(struct tty *tp)
132 {
133 tty_assert_locked(tp);
134 MPASS(!tty_gone(tp));
135
136 return tp->t_hook->th_getc_poll(tp);
137 }
138
139 static __inline void
ttyhook_close(struct tty * tp)140 ttyhook_close(struct tty *tp)
141 {
142 tty_assert_locked(tp);
143
144 tp->t_hook->th_close(tp);
145 }
146
147 #endif /* !_SYS_TTYHOOK_H_ */
148