asterisk/main/tdd.c

363 lines
8.3 KiB
C

/*
* Asterisk -- An open source telephony toolkit.
*
* Copyright (C) 1999 - 2005, Digium, Inc.
*
* Mark Spencer <markster@digium.com>
*
* Includes code and algorithms from the Zapata library.
*
* See http://www.asterisk.org for more information about
* the Asterisk project. Please do not directly contact
* any of the maintainers of this project for assistance;
* the project provides a web site, mailing lists and IRC
* channels for your use.
*
* This program is free software, distributed under the terms of
* the GNU General Public License Version 2. See the LICENSE file
* at the top of the source tree.
*/
/*! \file
*
* \brief TTY/TDD Generation support
*
* \author Mark Spencer <markster@digium.com>
*
* \note Includes code and algorithms from the Zapata library.
*/
/*** MODULEINFO
<support_level>core</support_level>
***/
#include "asterisk.h"
#include <time.h>
#include <math.h>
#include <ctype.h>
#include "asterisk/logger.h"
#include "asterisk/ulaw.h"
#include "asterisk/tdd.h"
#include "asterisk/fskmodem.h"
#include "asterisk/utils.h"
#include "ecdisa.h"
struct tdd_state {
fsk_data fskd;
char rawdata[256];
short oldstuff[4096];
int oldlen;
int pos;
int modo;
int mode;
int charnum;
};
static float dr[4], di[4];
static float tddsb = 176.0; /* 45.5 baud */
#define TDD_SPACE 1800.0 /* 1800 hz for "0" */
#define TDD_MARK 1400.0 /* 1400 hz for "1" */
static int tdd_decode_baudot(struct tdd_state *tdd,unsigned char data) /* covert baudot into ASCII */
{
static char ltrs[32] = { '<','E','\n','A',' ','S','I','U',
'\n','D','R','J','N','F','C','K',
'T','Z','L','W','H','Y','P','Q',
'O','B','G','^','M','X','V','^' };
static char figs[32] = { '<','3','\n','-',' ','\'','8','7',
'\n','$','4','\'',',','!',':','(',
'5','\"',')','2','=','6','0','1',
'9','?','+','^','.','/',';','^' };
int d = 0; /* return 0 if not decodeable */
if (data < 32) {
switch (data) {
case 0x1f:
tdd->modo = 0;
break;
case 0x1b:
tdd->modo = 1;
break;
default:
if (tdd->modo == 0)
d = ltrs[data];
else
d = figs[data];
break;
}
}
return d;
}
void tdd_init(void)
{
/* Initialize stuff for inverse FFT */
dr[0] = cos(TDD_SPACE * 2.0 * M_PI / 8000.0);
di[0] = sin(TDD_SPACE * 2.0 * M_PI / 8000.0);
dr[1] = cos(TDD_MARK * 2.0 * M_PI / 8000.0);
di[1] = sin(TDD_MARK * 2.0 * M_PI / 8000.0);
}
struct tdd_state *tdd_new(void)
{
struct tdd_state *tdd;
tdd = ast_calloc(1, sizeof(*tdd));
if (tdd) {
#ifdef INTEGER_CALLERID
tdd->fskd.ispb = 176; /* 45.5 baud */
/* Set up for 45.5 / 8000 freq *32 to allow ints */
tdd->fskd.pllispb = (int)((8000 * 32 * 2) / 90);
tdd->fskd.pllids = tdd->fskd.pllispb / 32;
tdd->fskd.pllispb2 = tdd->fskd.pllispb / 2;
tdd->fskd.hdlc = 0; /* Async */
tdd->fskd.nbit = 5; /* 5 bits */
tdd->fskd.instop = 1; /* integer rep of 1.5 stop bits */
tdd->fskd.parity = 0; /* No parity */
tdd->fskd.bw=0; /* Filter 75 Hz */
tdd->fskd.f_mark_idx = 0; /* 1400 Hz */
tdd->fskd.f_space_idx = 1; /* 1800 Hz */
tdd->fskd.xi0 = 0;
tdd->fskd.state = 0;
tdd->pos = 0;
tdd->mode = 0;
fskmodem_init(&tdd->fskd);
#else
tdd->fskd.spb = 176; /* 45.5 baud */
tdd->fskd.hdlc = 0; /* Async */
tdd->fskd.nbit = 5; /* 5 bits */
tdd->fskd.nstop = 1.5; /* 1.5 stop bits */
tdd->fskd.parity = 0; /* No parity */
tdd->fskd.bw=0; /* Filter 75 Hz */
tdd->fskd.f_mark_idx = 0; /* 1400 Hz */
tdd->fskd.f_space_idx = 1; /* 1800 Hz */
tdd->fskd.pcola = 0; /* No clue */
tdd->fskd.cont = 0; /* Digital PLL reset */
tdd->fskd.x0 = 0.0;
tdd->fskd.state = 0;
tdd->pos = 0;
tdd->mode = 2;
#endif
tdd->charnum = 0;
} else
ast_log(LOG_WARNING, "Out of memory\n");
return tdd;
}
int ast_tdd_gen_ecdisa(unsigned char *outbuf, int len)
{
int pos = 0;
int cnt;
while (len) {
cnt = len > sizeof(ecdisa) ? sizeof(ecdisa) : len;
memcpy(outbuf + pos, ecdisa, cnt);
pos += cnt;
len -= cnt;
}
return 0;
}
int tdd_feed(struct tdd_state *tdd, unsigned char *ubuf, int len)
{
int mylen = len;
int olen;
int b = 'X';
int res;
int c,x;
short *buf = ast_calloc(1, 2 * len + tdd->oldlen);
short *obuf = buf;
if (!buf) {
ast_log(LOG_WARNING, "Out of memory\n");
return -1;
}
memcpy(buf, tdd->oldstuff, tdd->oldlen);
mylen += tdd->oldlen / 2;
for (x = 0; x < len; x++)
buf[x + tdd->oldlen / 2] = AST_MULAW(ubuf[x]);
c = res = 0;
while (mylen >= 1320) { /* has to have enough to work on */
olen = mylen;
res = fsk_serial(&tdd->fskd, buf, &mylen, &b);
if (mylen < 0) {
ast_log(LOG_ERROR, "fsk_serial made mylen < 0 (%d) (olen was %d)\n", mylen, olen);
ast_free(obuf);
return -1;
}
buf += (olen - mylen);
if (res < 0) {
ast_log(LOG_NOTICE, "fsk_serial failed\n");
ast_free(obuf);
return -1;
}
if (res == 1) {
/* Ignore invalid bytes */
if (b > 0x7f)
continue;
c = tdd_decode_baudot(tdd, b);
if ((c < 1) || (c > 126))
continue; /* if not valid */
break;
}
}
if (mylen) {
memcpy(tdd->oldstuff, buf, mylen * 2);
tdd->oldlen = mylen * 2;
} else
tdd->oldlen = 0;
ast_free(obuf);
if (res) {
tdd->mode = 2;
/* put it in mode where it
reliably puts teleprinter in correct shift mode */
return(c);
}
return 0;
}
void tdd_free(struct tdd_state *tdd)
{
ast_free(tdd);
}
static inline float tdd_getcarrier(float *cr, float *ci, int bit)
{
/* Move along. There's nothing to see here... */
float t;
t = *cr * dr[bit] - *ci * di[bit];
*ci = *cr * di[bit] + *ci * dr[bit];
*cr = t;
t = 2.0 - (*cr * *cr + *ci * *ci);
*cr *= t;
*ci *= t;
return *cr;
}
#define PUT_BYTE(a) do { \
*(buf++) = (a); \
bytes++; \
} while(0)
#define PUT_AUDIO_SAMPLE(y) do { \
int __pas_idx = (short)(rint(8192.0 * (y))); \
*(buf++) = AST_LIN2MU(__pas_idx); \
bytes++; \
} while(0)
#define PUT_TDD_MARKMS do { \
int x; \
for (x = 0; x < 8; x++) \
PUT_AUDIO_SAMPLE(tdd_getcarrier(&cr, &ci, 1)); \
} while(0)
#define PUT_TDD_BAUD(bit) do { \
while (scont < tddsb) { \
PUT_AUDIO_SAMPLE(tdd_getcarrier(&cr, &ci, bit)); \
scont += 1.0; \
} \
scont -= tddsb; \
} while(0)
#define PUT_TDD_STOP do { \
while (scont < (tddsb * 1.5)) { \
PUT_AUDIO_SAMPLE(tdd_getcarrier(&cr, &ci, 1)); \
scont += 1.0; \
} \
scont -= (tddsb * 1.5); \
} while(0)
#define PUT_TDD(byte) do { \
int z; \
unsigned char b = (byte); \
PUT_TDD_BAUD(0); /* Start bit */ \
for (z = 0; z < 5; z++) { \
PUT_TDD_BAUD(b & 1); \
b >>= 1; \
} \
PUT_TDD_STOP; /* Stop bit */ \
} while(0);
/*! Generate TDD hold tone
* \todo How big should this be?
*/
int tdd_gen_holdtone(unsigned char *buf)
{
int bytes = 0;
float scont = 0.0, cr = 1.0, ci=0.0;
while (scont < tddsb * 10.0) {
PUT_AUDIO_SAMPLE(tdd_getcarrier(&cr, &ci, 1));
scont += 1.0;
}
return bytes;
}
int tdd_generate(struct tdd_state *tdd, unsigned char *buf, const char *str)
{
int bytes = 0;
int i,x;
char c;
/*! Baudot letters */
static unsigned char lstr[31] = "\000E\nA SIU\rDRJNFCKTZLWHYPQOBG\000MXV";
/*! Baudot figures */
static unsigned char fstr[31] = "\0003\n- \00787\r$4',!:(5\")2\0006019?+\000./;";
/* Initial carriers (real/imaginary) */
float cr = 1.0;
float ci = 0.0;
float scont = 0.0;
for(x = 0; str[x]; x++) {
/* Do synch for each 72th character */
if ( (tdd->charnum++) % 72 == 0)
PUT_TDD(tdd->mode ? 27 /* FIGS */ : 31 /* LTRS */);
c = toupper(str[x]);
#if 0
printf("%c",c); fflush(stdout);
#endif
if (c == 0) { /* send null */
PUT_TDD(0);
continue;
}
if (c == '\r') { /* send c/r */
PUT_TDD(8);
continue;
}
if (c == '\n') { /* send c/r and l/f */
PUT_TDD(8);
PUT_TDD(2);
continue;
}
if (c == ' ') { /* send space */
PUT_TDD(4);
continue;
}
for (i = 0; i < 31; i++) {
if (lstr[i] == c)
break;
}
if (i < 31) { /* if we found it */
if (tdd->mode) { /* if in figs mode, change it */
PUT_TDD(31); /* Send LTRS */
tdd->mode = 0;
}
PUT_TDD(i);
continue;
}
for (i = 0; i < 31; i++) {
if (fstr[i] == c)
break;
}
if (i < 31) { /* if we found it */
if (tdd->mode != 1) { /* if in ltrs mode, change it */
PUT_TDD(27); /* send FIGS */
tdd->mode = 1;
}
PUT_TDD(i); /* send byte */
continue;
}
}
return bytes;
}