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/* $Id $
*
* DVB specific functions
*
* Copyright 2003 by Michael Reinelt (reinelt@eunet.at)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
*
* $Log
*/
/*
* exported functions:
*
* DVB (int *strength, int *snr)
* returns 0 if ok, -1 if error
* sets *strength to the signal strength
* sets *snr to the signal/noise ratio
*
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <fcntl.h>
#include <time.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include "config.h"
#ifndef HAVE_LINUX_DVB_FRONTEND_H
#warning linux/dvb/frontend.h not found.
#warning DVB client will be disabled.
int DVB (double *strength, double *snr)
{
static int flag=0;
if (flag==0) {
error("lcd4linux has been compiled without DVB support");
error("DVB client will be disabled");
flag=1;
}
*strength=0.0;
*snr=0.0;
return 0;
}
#else
#include <linux/dvb/frontend.h>
#include "debug.h"
#include "dvb.h"
#include "filter.h"
int DVB (double *strength, double *snr)
{
static time_t now=0;
static int fd=-2;
static double strength0=0.0;
static double snr0=0.0;
unsigned short raw_strength;
unsigned short raw_snr;
*strength=strength0;
*snr=snr0;
if (fd==-1) return -1;
if (time(NULL)==now) return 0;
time(&now);
if (fd==-2) {
fd = open("/dev/dvb/adapter0/frontend0", O_RDONLY);
if (fd==-1) {
error ("open(/dev/dvb/adapter0/frontend0) failed: %s", strerror(errno));
return -1;
}
debug ("open (/dev/dvb/adapter0/frontend0)=%d", fd);
}
if (ioctl(fd, FE_READ_SIGNAL_STRENGTH, &raw_strength)) {
error("ioctl(FE_READ_SIGNAL_STRENGTH) failed: %s", strerror(errno));
fd=-1;
return -1;
}
if (ioctl(fd, FE_READ_SNR, &raw_snr)) {
error("ioctl(FE_READ_SNR) failed: %s", strerror(errno));
fd=-1;
return -1;
}
// Normalize to 1.0
strength0=raw_strength/65535.0;
snr0=raw_snr/65535.0;
*strength=strength0;
*snr=snr0;
return 0;
}
#endif
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