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/* $Id: wifi.c,v 1.1 2003/11/14 05:59:37 reinelt Exp $
*
* WIFI specific functions
*
* Copyright 2003 Xavier Vello <xavier66@free.fr>
*
* based on lcd4linux/isdn.c which is
* Copyright 1999, 2000 by Michael Reinelt (reinelt@eunet.at)
*
* This file is part of LCD4Linux.
*
* LCD4Linux 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.
*
* LCD4Linux 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: wifi.c,v $
* Revision 1.1 2003/11/14 05:59:37 reinelt
* added wifi.c wifi.h which have been forgotten at the last checkin
*
*/
/*
* exported functions:
*
* Wifi (int *signal, int *link, int *noise)
* returns 0 if ok, -1 if error
* sets *signal to signal level (which determines the rate)
* sets *link to link quality
* sets *noise to noise level (reverse of link quality)
*
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include "debug.h"
#include "wifi.h"
#include "filter.h"
typedef struct {
int signal;
int link;
int noise;
} CPS;
int Wifi (int *signal, int *link, int *noise)
{
*signal=0;
*link=0;
*noise=0;
int ws, wl, wn;
static int fd=-2;
char buffer[4096];
char *p;
if (fd==-1) return -1;
if (fd==-2) {
fd = open("/proc/net/wireless", O_RDONLY); // the real procfs file
// fd = open("/wireless", O_RDONLY); // a fake file for testing
if (fd==-1) {
error ("open(/proc/net/wireless) failed: %s", strerror(errno));
return -1;
}
debug ("open(/proc/net/wireless)=%d", fd);
}
if (lseek(fd, 0L, SEEK_SET)!=0) {
error ("lseek(/proc/net/wireless) failed: %s", strerror(errno));
fd=-1;
return -1;
}
if (read (fd, &buffer, sizeof(buffer)-1)==-1) {
error("read(/proc/net/wireless) failed: %s", strerror(errno));
fd=-1;
return -1;
}
p=strstr(buffer, "wlan0");
if (p!=NULL) {
if (sscanf(p+13, "%d", &wl)!=1) {
error ("parse(/proc/net/wireless) failed: unknown format");
fd=-1;
return -1;
}
if (sscanf(p+19, "%d", &ws)!=1) {
error ("parse(/proc/net/wireless) failed: unknown format");
fd=-1;
return -1;
}
if (sscanf(p+25, "%d", &wn)!=1) {
error ("parse(/proc/net/wireless) failed: unknown format");
fd=-1;
return -1;
}
} else {
error("read(/proc/net/wireless) failed: %s", strerror(errno));
fd=-1;
return -1;
}
*signal=ws;
*link=wl;
*noise=wn;
return 0;
}
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