1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
|
/*
* Copyright (c) 2023-2024 Ian Marco Moffett and the Osmora Team.
* All rights reserved.
*
* 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. Neither the name of Hyra 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 COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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.
*/
#include <sys/tty.h>
#include <sys/cdefs.h>
#include <sys/errno.h>
#include <sys/syslog.h>
#include <fs/devfs.h>
#include <string.h>
static dev_t tty_major = 0;
struct tty g_root_tty = {
.scr = &g_syslog_screen,
.ring = {
.enq_index = 0,
.deq_index = 0,
}
};
static inline dev_t
tty_alloc_id(void)
{
static dev_t id = 1;
return id++;
}
/*
* Flushes the TTY ring buffer.
*
* @tty: TTY to flush.
*
* Returns number of bytes flushed.
*/
static ssize_t
__tty_flush(struct tty *tty)
{
struct tty_ring *ring = &tty->ring;
size_t count = 0;
char tmp;
/* Do we have any data left? */
if (ring->deq_index >= ring->enq_index)
return -EAGAIN;
/* Flush the ring */
while (ring->deq_index < ring->enq_index) {
tmp = ring->data[ring->deq_index++];
vcons_putch(tty->scr, tmp);
++count;
}
ring->enq_index = 0;
ring->deq_index = 0;
return count;
}
/*
* Device structure routine for reading a
* TTY device file.
*/
static int
tty_dev_read(struct device *dev, struct sio_txn *sio)
{
struct tty_ring *ring = &g_root_tty.ring;
size_t len;
spinlock_acquire(&g_root_tty.rlock);
len = (ring->enq_index - ring->deq_index);
/*
* Transfer data from the TTY ring with SIO and
* flush it.
*
* TODO: As of now we are just reading the root
* TTY, add support for multiple TTYs.
*/
memcpy(sio->buf, ring->data, len);
__tty_flush(&g_root_tty);
spinlock_release(&g_root_tty.rlock);
return len;
}
/*
* Serialized wrapper over __tty_flush()
*/
ssize_t
tty_flush(struct tty *tty)
{
ssize_t ret;
spinlock_acquire(&tty->rlock);
ret = __tty_flush(tty);
spinlock_release(&tty->rlock);
return ret;
}
/*
* Write a character to a TTY
*
* @tty: TTY to write to.
* @c: Character to write.
*/
int
tty_putc(struct tty *tty, int c)
{
struct tty_ring *ring;
ring = &tty->ring;
spinlock_acquire(&tty->rlock);
ring->data[ring->enq_index++] = c;
if (ring->enq_index >= TTY_RING_SIZE) {
__tty_flush(tty);
}
spinlock_release(&tty->rlock);
return 0;
}
dev_t
tty_attach(struct tty *tty)
{
int tmp;
char devname[128];
struct device *dev = device_alloc();
if (dev == NULL)
return -ENOMEM;
/*
* Allocate a major for the driver if we don't
* have one yet.
*/
if (tty_major == 0)
tty_major = device_alloc_major();
/* Now try to create the device */
tty->id = tty_alloc_id();
if ((tmp = device_create(dev, tty_major, tty->id)) < 0)
return tmp;
dev->read = tty_dev_read;
dev->blocksize = 1;
snprintf(devname, sizeof(devname), "tty%d", tty->id);
return devfs_add_dev(devname, dev);
}
|