projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| c6e3fd22 | 1 | #include <linux/console.h> |
| c6e3fd22 WH |
2 | #include <linux/types.h> |
| 3 | #include <linux/wait.h> | |
| 4 | ||
| 5 | #include "speakup.h" | |
| 6 | #include "spk_priv.h" | |
| 7 | ||
| 5c75af1a | 8 | #define SYNTH_BUF_SIZE 8192 /* currently 8K bytes */ |
| c6e3fd22 | 9 | |
| 5c75af1a | 10 | static u_char synth_buffer[SYNTH_BUF_SIZE]; /* guess what this is for! */ |
| c6e3fd22 WH |
11 | static u_char *buff_in = synth_buffer; |
| 12 | static u_char *buff_out = synth_buffer; | |
| 5c75af1a | 13 | static u_char *buffer_end = synth_buffer + SYNTH_BUF_SIZE - 1; |
| c6e3fd22 WH |
14 | |
| 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. | |
| 19 | * | |
| 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. | |
| 22 | */ | |
| 23 | void speakup_start_ttys(void) | |
| 24 | { | |
| 25 | int i; | |
| 26 | ||
| 27 | for (i = 0; i < MAX_NR_CONSOLES; i++) { | |
| 28 | if (speakup_console[i] && speakup_console[i]->tty_stopped) | |
| 29 | continue; | |
| d3da1cba | 30 | if ((vc_cons[i].d) && (vc_cons[i].d->port.tty)) |
| 5b19208a | 31 | start_tty(vc_cons[i].d->port.tty); |
| c6e3fd22 WH |
32 | } |
| 33 | } | |
| 34 | EXPORT_SYMBOL_GPL(speakup_start_ttys); | |
| 35 | ||
| 36 | static void speakup_stop_ttys(void) | |
| 37 | { | |
| 38 | int i; | |
| 39 | ||
| 40 | for (i = 0; i < MAX_NR_CONSOLES; i++) | |
| d3da1cba | 41 | if ((vc_cons[i].d && (vc_cons[i].d->port.tty))) |
| 5b19208a | 42 | stop_tty(vc_cons[i].d->port.tty); |
| c6e3fd22 WH |
43 | } |
| 44 | ||
| 45 | static int synth_buffer_free(void) | |
| 46 | { | |
| 5c75af1a | 47 | int bytes_free; |
| c6e3fd22 WH |
48 | |
| 49 | if (buff_in >= buff_out) | |
| 5c75af1a | 50 | bytes_free = SYNTH_BUF_SIZE - (buff_in - buff_out); |
| c6e3fd22 | 51 | else |
| 5c75af1a LA |
52 | bytes_free = buff_out - buff_in; |
| 53 | return bytes_free; | |
| c6e3fd22 WH |
54 | } |
| 55 | ||
| 56 | int synth_buffer_empty(void) | |
| 57 | { | |
| 58 | return (buff_in == buff_out); | |
| 59 | } | |
| 60 | EXPORT_SYMBOL_GPL(synth_buffer_empty); | |
| 61 | ||
| 62 | void synth_buffer_add(char ch) | |
| 63 | { | |
| 64 | if (!synth->alive) { | |
| 65 | /* This makes sure that we won't stop TTYs if there is no synth | |
| 13d825ed AF |
66 | * to restart them |
| 67 | */ | |
| c6e3fd22 WH |
68 | return; |
| 69 | } | |
| 70 | if (synth_buffer_free() <= 100) { | |
| 71 | synth_start(); | |
| 72 | speakup_stop_ttys(); | |
| 73 | } | |
| 74 | if (synth_buffer_free() <= 1) | |
| 75 | return; | |
| 76 | *buff_in++ = ch; | |
| 77 | if (buff_in > buffer_end) | |
| 78 | buff_in = synth_buffer; | |
| 79 | } | |
| 80 | ||
| 81 | char synth_buffer_getc(void) | |
| 82 | { | |
| 83 | char ch; | |
| 84 | ||
| 85 | if (buff_out == buff_in) | |
| 86 | return 0; | |
| 87 | ch = *buff_out++; | |
| 88 | if (buff_out > buffer_end) | |
| 89 | buff_out = synth_buffer; | |
| 90 | return ch; | |
| 91 | } | |
| 92 | EXPORT_SYMBOL_GPL(synth_buffer_getc); | |
| 93 | ||
| 94 | char synth_buffer_peek(void) | |
| 95 | { | |
| 96 | if (buff_out == buff_in) | |
| 97 | return 0; | |
| 98 | return *buff_out; | |
| 99 | } | |
| 100 | EXPORT_SYMBOL_GPL(synth_buffer_peek); | |
| 101 | ||
| 102 | void synth_buffer_clear(void) | |
| 103 | { | |
| a16d77fc BA |
104 | buff_in = synth_buffer; |
| 105 | buff_out = synth_buffer; | |
| c6e3fd22 WH |
106 | } |
| 107 | EXPORT_SYMBOL_GPL(synth_buffer_clear); |