Fix possible divide by null

Patch for mickeyl...

1 files changed, 2 insertions, 1 deletions

diff --git a/libopie2/opienet/onetwork.cpp b/libopie2/opienet/onetwork.cpp
index ab3e77f..26a6c81 100644
--- a/libopie2/opienet/onetwork.cpp
+++ b/libopie2/opienet/onetwork.cpp
@@ -913,193 +913,194 @@ OStationList* OWirelessNetworkInterface::scanNetwork()
 

     odebug << "ONetworkInterface::scanNetwork() - scan finished." << oendl;

 

     if ( results )

     {

         odebug << " - result length = " << _iwr.u.data.length << oendl;

         if ( !_iwr.u.data.length )

         {

             odebug << " - no results (empty neighbourhood)" << oendl;

             return stations;

         }

 

         odebug << " - results are in!" << oendl;

         dumpBytes( (const unsigned char*) &buffer[0], _iwr.u.data.length );

 

         // parse results

 

         int offset = 0;

         struct iw_event* we = (struct iw_event*) &buffer[0];

 

         while ( offset < _iwr.u.data.length )

         {

             //const char* cmd = *(*_ioctlmap)[we->cmd];

             //if ( !cmd ) cmd = "<unknown>";

             odebug << " - reading next event... cmd=" << we->cmd << ", len=" << we->len << oendl;

             switch (we->cmd)

             {

                 case SIOCGIWAP:

                 {

                     odebug << "SIOCGIWAP" << oendl;

                     stations->append( new OStation() );

                     stations->last()->macAddress = (const unsigned char*) &we->u.ap_addr.sa_data[0];

                     break;

                 }

                 case SIOCGIWMODE:

                 {

                     odebug << "SIOCGIWMODE" << oendl;

                     stations->last()->type = modeToString( we->u.mode );

                     break;

                 }

                 case SIOCGIWFREQ:

                 {

                     odebug << "SIOCGIWFREQ" << oendl;

                     stations->last()->channel = _channels[ static_cast<int>(double( we->u.freq.m ) * pow( 10.0, we->u.freq.e ) / 1000000) ];

                     break;

                 }

                 case SIOCGIWESSID:

                 {

                     odebug << "SIOCGIWESSID" << oendl;

                     stations->last()->ssid = we->u.essid.pointer;

                     break;

                 }

                 case SIOCGIWSENS: odebug << "SIOCGIWSENS" << oendl; break;

                 case SIOCGIWENCODE: odebug << "SIOCGIWENCODE" << oendl; break;

                 case IWEVTXDROP: odebug << "IWEVTXDROP" << oendl; break;         /* Packet dropped to excessive retry */

                 case IWEVQUAL: odebug << "IWEVQUAL" << oendl; break;             /* Quality part of statistics (scan) */

                 case IWEVCUSTOM: odebug << "IWEVCUSTOM" << oendl; break;         /* Driver specific ascii string */

                 case IWEVREGISTERED: odebug << "IWEVREGISTERED" << oendl; break; /* Discovered a new node (AP mode) */

                 case IWEVEXPIRED: odebug << "IWEVEXPIRED" << oendl; break;       /* Expired a node (AP mode) */

                 default: odebug << "unhandled event" << oendl;

             }

 

             offset += we->len;

             we = (struct iw_event*) &buffer[offset];

         }

         return stations;

 

         return stations;

 

     }

     else

     {

         odebug << " - no results (timeout) :(" << oendl;

         return stations;

     }

 }

 

 

 int OWirelessNetworkInterface::signalStrength() const

 {

     iw_statistics stat;

     ::memset( &stat, 0, sizeof stat );

     _iwr.u.data.pointer = (char*) &stat;

     _iwr.u.data.flags = 0;

     _iwr.u.data.length = sizeof stat;

 

     if ( !wioctl( SIOCGIWSTATS ) )

     {

         return -1;

     }

 

     int max = _range.max_qual.qual;

     int cur = stat.qual.qual;

     int lev = stat.qual.level; //FIXME: Do something with them?

     int noi = stat.qual.noise; //FIXME: Do something with them?

 

-    return cur*100/max;

+

+    return max != 0 ? cur*100/max: -1;

 }

 

 

 bool OWirelessNetworkInterface::wioctl( int call, struct iwreq& iwreq ) const

 {

     #ifndef NODEBUG

     int result = ::ioctl( _sfd, call, &iwreq );

 

     if ( result == -1 )

         odebug << "ONetworkInterface::wioctl (" << name() << ") call '"

                << debugmapper->map( call ) << "' FAILED! " << result << " (" << strerror( errno ) << ")" << oendl;

     else

         odebug << "ONetworkInterface::wioctl (" << name() << ") call '"

                << debugmapper->map( call ) << "' - Status: Ok." << oendl;

 

     return ( result != -1 );

     #else

     return ::ioctl( _sfd, call, &iwreq ) != -1;

     #endif

 }

 

 

 bool OWirelessNetworkInterface::wioctl( int call ) const

 {

     strcpy( _iwr.ifr_name, name() );

     return wioctl( call, _iwr );

 }

 

 

 /*======================================================================================

  * OMonitoringInterface

  *======================================================================================*/

 

 OMonitoringInterface::OMonitoringInterface( ONetworkInterface* iface, bool prismHeader )

                       :_if( static_cast<OWirelessNetworkInterface*>( iface ) ), _prismHeader( prismHeader )

 {

 }

 

 

 OMonitoringInterface::~OMonitoringInterface()

 {

 }

 

 

 void OMonitoringInterface::setChannel( int c )

 {

     // use standard WE channel switching protocol

     memset( &_if->_iwr, 0, sizeof( struct iwreq ) );

     _if->_iwr.u.freq.m = c;

     _if->_iwr.u.freq.e = 0;

     _if->wioctl( SIOCSIWFREQ );

 }

 

 

 void OMonitoringInterface::setEnabled( bool b )

 {

 }

 

 

 /*======================================================================================

  * OCiscoMonitoringInterface

  *======================================================================================*/

 

 OCiscoMonitoringInterface::OCiscoMonitoringInterface( ONetworkInterface* iface, bool prismHeader )

                            :OMonitoringInterface( iface, prismHeader )

 {

     iface->setMonitoring( this );

 }

 

 

 OCiscoMonitoringInterface::~OCiscoMonitoringInterface()

 {

 }

 

 

 void OCiscoMonitoringInterface::setEnabled( bool b )

 {

     QString fname;

     fname.sprintf( "/proc/driver/aironet/%s", (const char*) _if->name() );

     QFile f( fname );

     if ( !f.exists() ) return;

 

     if ( f.open( IO_WriteOnly ) )

     {

         QTextStream s( &f );

         s << "Mode: r";

         s << "Mode: y";

         s << "XmitPower: 1";

     }

 

     // flushing and closing will be done automatically when f goes out of scope

 }

 

 

 QString OCiscoMonitoringInterface::name() const

 {