1 #include <linux/console.h>
2 #include <linux/types.h>
3 #include <linux/wait.h>
8 #define SYNTH_BUF_SIZE 8192 /* currently 8K bytes */
10 static u_char synth_buffer[SYNTH_BUF_SIZE]; /* guess what this is for! */
11 static u_char *buff_in = synth_buffer;
12 static u_char *buff_out = synth_buffer;
13 static u_char *buffer_end = synth_buffer + SYNTH_BUF_SIZE - 1;
15 /* These try to throttle applications by stopping the TTYs
16 * Note: we need to make sure that we will restart them eventually, which is
17 * usually not possible to do from the notifiers. TODO: it should be possible
18 * starting from linux 2.6.26.
20 * So we only stop when we know alive == 1 (else we discard the data anyway),
21 * and the alive synth will eventually call start_ttys from the thread context.
23 void speakup_start_ttys(void)
27 for (i = 0; i < MAX_NR_CONSOLES; i++) {
28 if (speakup_console[i] && speakup_console[i]->tty_stopped)
30 if ((vc_cons[i].d != NULL) && (vc_cons[i].d->port.tty != NULL))
31 start_tty(vc_cons[i].d->port.tty);
34 EXPORT_SYMBOL_GPL(speakup_start_ttys);
36 static void speakup_stop_ttys(void)
40 for (i = 0; i < MAX_NR_CONSOLES; i++)
41 if ((vc_cons[i].d != NULL) && (vc_cons[i].d->port.tty != NULL))
42 stop_tty(vc_cons[i].d->port.tty);
45 static int synth_buffer_free(void)
49 if (buff_in >= buff_out)
50 bytes_free = SYNTH_BUF_SIZE - (buff_in - buff_out);
52 bytes_free = buff_out - buff_in;
56 int synth_buffer_empty(void)
58 return (buff_in == buff_out);
60 EXPORT_SYMBOL_GPL(synth_buffer_empty);
62 void synth_buffer_add(char ch)
65 /* This makes sure that we won't stop TTYs if there is no synth
70 if (synth_buffer_free() <= 100) {
74 if (synth_buffer_free() <= 1)
77 if (buff_in > buffer_end)
78 buff_in = synth_buffer;
81 char synth_buffer_getc(void)
85 if (buff_out == buff_in)
88 if (buff_out > buffer_end)
89 buff_out = synth_buffer;
92 EXPORT_SYMBOL_GPL(synth_buffer_getc);
94 char synth_buffer_peek(void)
96 if (buff_out == buff_in)
100 EXPORT_SYMBOL_GPL(synth_buffer_peek);
102 void synth_buffer_clear(void)
104 buff_in = synth_buffer;
105 buff_out = synth_buffer;
107 EXPORT_SYMBOL_GPL(synth_buffer_clear);