I am writing an Android app that should exchange data to a server over Bluetooth, with the server side on a PC running Ubuntu, using the bluez library, in C (or C++).
My Android app fails (IOException) when I try to connect to my server socket on the PC.
Here is essentially what I in the java code (in Android, full eclipse project here: http://dl.dropbox.com/u/2968234/ThinBTClient.zip)
private static final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
private static String address = "00:02:72:B2:85:C7"; // Hard coded for simplicity
private BluetoothAdapter mBluetoothAdapter = null;
private BluetoothSocket btSocket = null;
.....
mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(address);
btSocket = device.createRfcommSocketToServiceRecord(MY_UUID);
btSocket.connect(); // This throws IOException after a timeout of 10seconds or so.
On the server side (in Ubuntu 8.10), I basically set up a Bluetooth server socket, along the lines described in the example bluez/sdp-register.c
Down below is my C++ program. To compile it do
g++ -I/usr/include/glib-2.0/ -I/usr/lib/glib-2.0/include -o bt_server bt_server.cpp -lbluetooth
I can do the reverse succesfully, i.e. create a server socket in Android and connect from Linux, however this is not what I want to do! I think either the problem has to do with my config of Ubuntu but I cannot seem to figure this one out and any help would be greatly appreciated!
#include <stdio.h>
#include <errno.h>
#include <fcntl.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <bluetooth/bluetooth.h>
#include <bluetooth/bluetooth.h>
#include <bluetooth/sdp.h>
#include <bluetooth/sco.h>
#include <bluetooth/sdp_lib.h>
#include <bluetooth/rfcomm.h>
#include <bluetooth/l2cap.h>
#include <glib.h>
sdp_session_t* register_service(uint8_t rfcomm_channel)
{
// Adapted from http://www.btessentials.com/examples/bluez/sdp-register.c
uint32_t svc_uuid_int[] = { 0x01110000, 0x00100000, 0x80000080, 0xFB349B5F };
const char *service_name = "Roto-Rooter Data Router";
const char *svc_dsc = "An experimental plumbing router";
const char *service_prov = "Roto-Rooter";
uuid_t root_uuid, l2cap_uuid, rfcomm_uuid, svc_uuid,
svc_class_uuid;
sdp_list_t *l2cap_list = 0,
*rfcomm_list = 0,
*root_list = 0,
*proto_list = 0,
*access_proto_list = 0,
*svc_class_list = 0,
*profile_list = 0;
sdp_data_t *channel = 0;
sdp_profile_desc_t profile;
sdp_record_t record = { 0 };
sdp_session_t *session = 0;
// set the general service ID
sdp_uuid128_create( &svc_uuid, &svc_uuid_int );
sdp_set_service_id( &record, svc_uuid );
char str[256] = "";
sdp_uuid2strn(&svc_uuid, str, 256);
printf("Registering UUID %s\n", str);
// set the service class
sdp_uuid16_create(&svc_class_uuid, SERIAL_PORT_SVCLASS_ID);
svc_class_list = sdp_list_append(0, &svc_class_uuid);
sdp_set_service_classes(&record, svc_class_list);
// set the Bluetooth profile information
sdp_uuid16_create(&profile.uuid, SERIAL_PORT_PROFILE_ID);
profile.version = 0x0100;
profile_list = sdp_list_append(0, &profile);
sdp_set_profile_descs(&record, profile_list);
// make the service record publicly browsable
sdp_uuid16_create(&root_uuid, PUBLIC_BROWSE_GROUP);
root_list = sdp_list_append(0, &root_uuid);
sdp_set_browse_groups( &record, root_list );
// set l2cap information
sdp_uuid16_create(&l2cap_uuid, L2CAP_UUID);
l2cap_list = sdp_list_append( 0, &l2cap_uuid );
proto_list = sdp_list_append( 0, l2cap_list );
// register the RFCOMM channel for RFCOMM sockets
sdp_uuid16_create(&rfcomm_uuid, RFCOMM_UUID);
channel = sdp_data_alloc(SDP_UINT8, &rfcomm_channel);
rfcomm_list = sdp_list_append( 0, &rfcomm_uuid );
sdp_list_append( rfcomm_list, channel );
sdp_list_append( proto_list, rfcomm_list );
access_proto_list = sdp_list_append( 0, proto_list );
sdp_set_access_protos( &record, access_proto_list );
// set the name, provider, and description
sdp_set_info_attr(&record, service_name, service_prov, svc_dsc);
// connect to the local SDP server, register the service record,
// and disconnect
session = sdp_connect(BDADDR_ANY, BDADDR_LOCAL, SDP_RETRY_IF_BUSY);
sdp_record_register(session, &record, 0);
// cleanup
sdp_data_free( channel );
sdp_list_free( l2cap_list, 0 );
sdp_list_free( rfcomm_list, 0 );
sdp_list_free( root_list, 0 );
sdp_list_free( access_proto_list, 0 );
sdp_list_free( svc_class_list, 0 );
sdp_list_free( profile_list, 0 );
return session;
}
int main(int argc, char **argv)
{
int port = 3;
sdp_session_t* session = register_service(port);
struct sockaddr_rc loc_addr = { 0 }, rem_addr = { 0 };
char buf[1024] = { 0 };
int s, client, bytes_read;
socklen_t opt = sizeof(rem_addr);
// allocate socket
s = socket(AF_BLUETOOTH, SOCK_STREAM, BTPROTO_RFCOMM);
printf("socket() returned %d\n", s);
// bind socket to port 1 of the first available
// local bluetooth adapter
loc_addr.rc_family = AF_BLUETOOTH;
loc_addr.rc_bdaddr = *BDADDR_ANY;
loc_addr.rc_channel = (uint8_t) port;
int r;
r = bind(s, (struct sockaddr *)&loc_addr, sizeof(loc_addr));
printf("bind() on channel %d returned %d\n", port, r);
// put socket into listening mode
r = listen(s, 1);
printf("listen() returned %d\n", r);
//sdpRegisterL2cap(port);
// accept one connection
printf("calling accept()\n");
client = accept(s, (struct sockaddr *)&rem_addr, &opt);
printf("accept() returned %d\n", client);
ba2str( &rem_addr.rc_bdaddr, buf );
fprintf(stderr, "accepted connection from %s\n", buf);
memset(buf, 0, sizeof(buf));
// read data from the client
bytes_read = read(client, buf, sizeof(buf));
if( bytes_read > 0 ) {
printf("received [%s]\n", buf);
}
// close connection
close(client);
close(s);
sdp_close( session );
return 0;
}