blob: d4d45989b6050a33051fbf66c46866596bc97e28 (
plain)
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
|
#include <linux/console.h>
#include <linux/types.h>
#include <linux/wait.h>
#include "speakup.h"
#include "spk_priv.h"
#define SYNTH_BUF_SIZE 8192 /* currently 8K bytes */
static u_char synth_buffer[SYNTH_BUF_SIZE]; /* guess what this is for! */
static u_char *buff_in = synth_buffer;
static u_char *buff_out = synth_buffer;
static u_char *buffer_end = synth_buffer + SYNTH_BUF_SIZE - 1;
/* These try to throttle applications by stopping the TTYs
* Note: we need to make sure that we will restart them eventually, which is
* usually not possible to do from the notifiers. TODO: it should be possible
* starting from linux 2.6.26.
*
* So we only stop when we know alive == 1 (else we discard the data anyway),
* and the alive synth will eventually call start_ttys from the thread context.
*/
void speakup_start_ttys(void)
{
int i;
for (i = 0; i < MAX_NR_CONSOLES; i++) {
if (speakup_console[i] && speakup_console[i]->tty_stopped)
continue;
if ((vc_cons[i].d != NULL) && (vc_cons[i].d->port.tty != NULL))
start_tty(vc_cons[i].d->port.tty);
}
}
EXPORT_SYMBOL_GPL(speakup_start_ttys);
static void speakup_stop_ttys(void)
{
int i;
for (i = 0; i < MAX_NR_CONSOLES; i++)
if ((vc_cons[i].d != NULL) && (vc_cons[i].d->port.tty != NULL))
stop_tty(vc_cons[i].d->port.tty);
}
static int synth_buffer_free(void)
{
int bytes_free;
if (buff_in >= buff_out)
bytes_free = SYNTH_BUF_SIZE - (buff_in - buff_out);
else
bytes_free = buff_out - buff_in;
return bytes_free;
}
int synth_buffer_empty(void)
{
return (buff_in == buff_out);
}
EXPORT_SYMBOL_GPL(synth_buffer_empty);
void synth_buffer_add(char ch)
{
if (!synth->alive) {
/* This makes sure that we won't stop TTYs if there is no synth
* to restart them
*/
return;
}
if (synth_buffer_free() <= 100) {
synth_start();
speakup_stop_ttys();
}
if (synth_buffer_free() <= 1)
return;
*buff_in++ = ch;
if (buff_in > buffer_end)
buff_in = synth_buffer;
}
char synth_buffer_getc(void)
{
char ch;
if (buff_out == buff_in)
return 0;
ch = *buff_out++;
if (buff_out > buffer_end)
buff_out = synth_buffer;
return ch;
}
EXPORT_SYMBOL_GPL(synth_buffer_getc);
char synth_buffer_peek(void)
{
if (buff_out == buff_in)
return 0;
return *buff_out;
}
EXPORT_SYMBOL_GPL(synth_buffer_peek);
void synth_buffer_clear(void)
{
buff_in = buff_out = synth_buffer;
}
EXPORT_SYMBOL_GPL(synth_buffer_clear);
|
