Pacp - Send Data
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Hi,
I use "pcap".
I wanna send and receive data.
But I have an error while sending the packet and "pcap_sendpacket" function return "-1".INCLUDEPATH += D:/WpdPack/Include LIBS += -L"D:/WpdPack/Lib" -lwpcap -lPacket code_textmain.cpp
QThread thread; thread.setObjectName("PCAPNetworkThread"); mySerialPort.moveToThread(&thread); QObject::connect(&thread, SIGNAL(started()), &pcapNetwork, SLOT(openLanPort())); thread.start();PCAPNetwork.cs
void PCAPNetwork::openLanPort() { pcap_if_t *alldevs; pcap_if_t *d; int inum; int i=0; char errbuf[PCAP_ERRBUF_SIZE]; if (pcap_findalldevs( &alldevs, errbuf) == -1) { //Error in pcap_findalldevs return; } /* Print the list */ for(d=alldevs; d; d=d->next) { //print name and description } if(i==0) { //No interfaces found! Make sure WinPcap is installed return; } //Enter the interface number inum=1;//I do not know how can I select adapter with mac address if(inum < 1 || inum > i) { //Interface number out of range /* Free the device list */ pcap_freealldevs(alldevs); return; } /* Jump to the selected adapter */ for(d=alldevs, i=0; i< inum-1 ;d=d->next, i++); /* Open the device */ if ( (adhandle= pcap_open_live(d->name, 65536, 1, 1000, NULL ) ) == NULL) { //Unable to open the adapter. /* Free the device list */ pcap_freealldevs(alldevs); return; } //listening pcap_freealldevs(alldevs); commandData(); pcap_loop(adhandle, 0, packet_handler, NULL); } void PCAPNetwork::commandData(){ QByteArray data; data[0]=commands->COMMANDS_DATA; sendData(data); } void PCAPNetwork::sendData(const QByteArray &data) { const u_char* p; std::memcpy(&p,data.constData(),data.size()); if(pcap_sendpacket(adhandle, p, sizeof(p) ) != 0 ) { //Error sending the packet qDebug()<<"Error: "<<pcap_geterr( adhandle ); return; } }@neda said in Pacp - Send Data:
fprintf( stderr,"\nError sending the packet: \n", pcap_geterr( adhandle ));
What does this line print out?
And I'm not sure what this has to do with Qt. -
@neda said in Pacp - Send Data:
fprintf( stderr,"\nError sending the packet: \n", pcap_geterr( adhandle ));
What does this line print out?
And I'm not sure what this has to do with Qt. -
@jsulm said in Pacp - Send Data:
What does this line print out?
PacketSendPacket failed
And I'm not sure what this has to do with Qt.
I did not find a document or a good sample to use "pcap" in Qt.
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@neda
Hi
And you did install winpcap/Win10Pcap so the driver is running?
Also, you are using visual studio compiler ?
Im not sure it works with mingw.@mrjj said in Pacp - Send Data:
Also, you are using visual studio compiler ?
Qt 5.12.5 MSVC2017 32bit
And you did install winpcap/Win10Pcap so the driver is running?
I installed "http://www.win10pcap.org/download/Win10Pcap-v10.2-5002.msi".
Now "pcap_sendpacket" return 0, It's OK.
But I do not have a correct answer from the device.I have a "QByteArray" Data for send such as:
"\x02\xFF\xFF\xFF\xFF\xFF\xFF\xFF"I don't know this code is true or not.
void PCAPNetwork::sendData(const QByteArray &data) { const u_char* p= reinterpret_cast<const uchar *>(data.constData()); //std::memcpy(&p,data.constData(),data.size()); pcap_sendpacket(adhandle, p, sizeof(p) ); -
@mrjj said in Pacp - Send Data:
Also, you are using visual studio compiler ?
Qt 5.12.5 MSVC2017 32bit
And you did install winpcap/Win10Pcap so the driver is running?
I installed "http://www.win10pcap.org/download/Win10Pcap-v10.2-5002.msi".
Now "pcap_sendpacket" return 0, It's OK.
But I do not have a correct answer from the device.I have a "QByteArray" Data for send such as:
"\x02\xFF\xFF\xFF\xFF\xFF\xFF\xFF"I don't know this code is true or not.
void PCAPNetwork::sendData(const QByteArray &data) { const u_char* p= reinterpret_cast<const uchar *>(data.constData()); //std::memcpy(&p,data.constData(),data.size()); pcap_sendpacket(adhandle, p, sizeof(p) ); -
I think I was wrong in reading data.
The device sends a lot of data in real-time.
I read them by this code.void PCAPNetwork::packet_handler(u_char *param, const struct pcap_pkthdr *header, const u_char *pkt_data) {How can I convert "pkt_data" to decimal?
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I think I was wrong in reading data.
The device sends a lot of data in real-time.
I read them by this code.void PCAPNetwork::packet_handler(u_char *param, const struct pcap_pkthdr *header, const u_char *pkt_data) {How can I convert "pkt_data" to decimal?
@neda said in Pacp - Send Data:
u_char
But is this not a byte already ?
If you place cursor on u_char and press F2, what is it then defined as?
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@neda said in Pacp - Send Data:
u_char
But is this not a byte already ?
If you place cursor on u_char and press F2, what is it then defined as?
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u_char = unsigned char
qDebug()<<"data: "<<pkt_data;output:
data: 0x46c16bcI don't know how can I convert it to decimal.
@neda
Is it zero terminated ?That is the address it writes out. Not the actual data i think.
You can convert it to bytearray
QByteArray databuf = QByteArray(reinterpret_cast<char*>(pkt_data), header->len);
(i think but not 100% sure header->len is data len. check docs) -
@neda
Is it zero terminated ?That is the address it writes out. Not the actual data i think.
You can convert it to bytearray
QByteArray databuf = QByteArray(reinterpret_cast<char*>(pkt_data), header->len);
(i think but not 100% sure header->len is data len. check docs) -
@mrjj said in Pacp - Send Data:
Not the actual data i think.
You right.
The device sends a lot of data in real-time.
How can I read the actual data?
