Question

i have problem i can’t solve for a while.
For one of my C++ projects i have to write function to change Bluetooth radio local name.
It uses Microsoft Bluetooth stack. You can find this name if you open any Bluetooth dongle device properties and navigate to Advanced Properties.
I need this without any third-party libraries, only WinApi functions. Need to do it in the way Windows Device Manager do. The problem is that i didn’t figure out how it do it. BluetoothAPI and Setupapi seem to be useless here. SetupDiSetDeviceRegistryProperty with SPDRP_FRIENDLYNAME parameter isn’t what i need. Changing local name in registry also do nothing. Maybe i should somehow restart bluetooth stack after that. I don’t know. So, how can i programmatically change device advanced properties? Thanks in advance.

Answer 1

I found the solution myself:

#include <windows.h>
#include <Setupapi.h>
#include <stdio.h>
#include <tchar.h>
#include <cfgmgr32.h>
#include <devguid.h>
#include <string>
#pragma comment(lib,"setupapi.lib")
using namespace std;

#define WIN32_LEAN_AND_MEAN

typedef basic_string<TCHAR> tstring;
DEFINE_GUID(GUID_DEVCLASS_BLUETOOTH, {0xe0cbf06cL, 0xcd8b, 0x4647, {0xbb, 0x8a, 0x26, 0x3b, 0x43, 0xf0, 0xf9, 0x74}});


LPTSTR GetGenericBluetoothAdapterInstanceID(void)
{
        unsigned i;    
        CONFIGRET r;
        HDEVINFO hDevInfo;
        SP_DEVINFO_DATA DeviceInfoData;
        PTSTR deviceInstanceID = new TCHAR[MAX_DEVICE_ID_LEN];

        // Find all bluetooth radio modules
        hDevInfo = SetupDiGetClassDevs(&GUID_DEVCLASS_BLUETOOTH, NULL, NULL, DIGCF_PRESENT);

        if (hDevInfo == INVALID_HANDLE_VALUE)
                return NULL;   

        // Get first Generic Bluetooth Adapter InstanceID
        for (i = 0; ; i++)  
        {              
                DeviceInfoData.cbSize = sizeof (DeviceInfoData);

                if (!SetupDiEnumDeviceInfo(hDevInfo, i, &DeviceInfoData))
                        break;

                r = CM_Get_Device_ID(DeviceInfoData.DevInst, deviceInstanceID , MAX_PATH, 0);

                if (r != CR_SUCCESS)
                        continue;

                if (_tcsncmp(_TEXT("USB"), deviceInstanceID, 3) == 0)
                {                      
                        return deviceInstanceID;
                }
        }

        return NULL;
}

void find_and_replace(LPTSTR source, LPCTSTR strFind, LPCTSTR strReplace)
{
        tstring s = tstring(source);
        tstring f = tstring(strFind);
        tstring r = tstring(strReplace);       
        size_t j;

        for ( ; (j = s.find( f )) != string::npos ; )
        {
                s.replace( j, f.length(), r );
        }

        _tcscpy(source, s.c_str());
}

int _tmain(int argc, TCHAR *argv[])
{
        if ( argc != 2 )
        {
                _tprintf( TEXT("Invalid parameters number. "
                        TEXT("Usage: Bthrmmodifier.exe <radio module local name>\n")));
                return 1;
        }

        LPTSTR instanceID = GetGenericBluetoothAdapterInstanceID();

        if (instanceID == NULL)
        {
                _tprintf(_TEXT("Failed to get Generic Bluetooth Adapter InstanceID\n"));
                return 1;
        }

        LPTSTR instanceIDModified = new TCHAR[_tcslen(instanceID)];
        _tcscpy(instanceIDModified, instanceID);
        find_and_replace(instanceIDModified, _TEXT("\\"), _TEXT("#"));

        HANDLE hDevice;
        TCHAR fileName[1024] = { 0 };  
        _tcscpy(fileName, _TEXT("\\\\.\\"));   
        _tcscat(fileName, instanceIDModified);
        _tcscat(fileName, _TEXT("#{a5dcbf10-6530-11d2-901f-00c04fb951ed}"));

        hDevice = CreateFile(fileName, GENERIC_WRITE, 0, NULL, OPEN_EXISTING, 0, NULL);

        if (hDevice == INVALID_HANDLE_VALUE)
        {
                _tprintf(_TEXT("Failed to open device. Error code: %d\n"), GetLastError());            
                return EXIT_FAILURE;
        }

        //Change radio module local name in registry
        LPTSTR RMLocalName = argv[1];
        CHAR bufRMLocalName[256];

        int nLength = WideCharToMultiByte(CP_UTF8, 0, RMLocalName,
                -1, NULL, 0, NULL, NULL);
        WideCharToMultiByte(CP_UTF8, 0, RMLocalName,
                -1, bufRMLocalName, nLength, NULL, NULL);

        HKEY hKey;
        TCHAR rmLocalNameKey[1024] = { 0 };
        LSTATUS ret;
        _tcscpy(rmLocalNameKey, _TEXT("SYSTEM\\ControlSet001\\Enum\\"));       
        _tcscat(rmLocalNameKey, instanceID);
        _tcscat(rmLocalNameKey, _TEXT("\\Device Parameters"));

        ret = RegOpenKeyEx(HKEY_LOCAL_MACHINE, rmLocalNameKey,
                0L, KEY_SET_VALUE , &hKey);

        if(ret != ERROR_SUCCESS)
        {
                _tprintf(TEXT("Failed to open registry key. Error code: %d\n"), ret);
                return EXIT_FAILURE;
        }

        ret = RegSetValueEx(hKey, _TEXT("Local Name"), 0, REG_BINARY,
                (LPBYTE)bufRMLocalName, nLength);

        if (ret != ERROR_SUCCESS)
        {
                _tprintf(TEXT("Failed to set registry key. Error code: %d\n"), ret);
                return EXIT_FAILURE;
        }

        RegCloseKey(hKey);

        // This check decides what IO control code to use based on if we're in XP or Vista (and later).
        OSVERSIONINFO osver;
        osver.dwOSVersionInfoSize = sizeof(osver);
        GetVersionEx(&osver);

        UINT ctlCode = (UINT)(6 > osver.dwMajorVersion ? 0x220fd4 : 0x411008);
        long reload = 4;  // tells the control function to reset or reload or similar...
        DWORD bytes = 0; // merely a placeholder

        // Send radio module driver command to update device information
        if (!DeviceIoControl(hDevice, ctlCode, &reload, 4, NULL, 0, &bytes, NULL))
        {
                _tprintf(TEXT("Failed to update radio module local name. Error code: %d\n"), GetLastError());
                return EXIT_FAILURE;
        }

        _tprintf(TEXT("Done\n"));

        return EXIT_SUCCESS;
}