How to get computer manufacturer and model from windows registry in C++? - c++

Question

I am writing my own C++ code to read the computer model and manufacturer on a Windows computer by reading and parsing the registry key
HKEY_LOCAL_MACHINE/SYSTEM/CurrentControlSet/services/mssmbios/Data/SMBiosData
Is there any library function in Windows / C++ / Visual Studio that allows me to get this information directly?

Answer 1

The steps you need are explained on Creating a WMI Application Using C++. MSDN even includes a sample program. You just need to change two strings.
Change SELECT * FROM Win32_Process to SELECT * FROM Win32_ComputerSystem
Change Name to Manufacturer and then again for Model.

Answer 2

With the help of the Microsoft example code, I was able to create this method.
#include <Wbemidl.h>
#pragma comment(lib, "wbemuuid.lib")
std::pair<CString,CString> getComputerManufacturerAndModel() {
// Obtain the initial locator to Windows Management on a particular host computer.
IWbemLocator *locator = nullptr;
IWbemServices *services = nullptr;
auto hResult = CoCreateInstance(CLSID_WbemLocator, 0, CLSCTX_INPROC_SERVER, IID_IWbemLocator, (LPVOID *)&locator);
auto hasFailed = [&hResult]() {
if (FAILED(hResult)) {
auto error = _com_error(hResult);
TRACE(error.ErrorMessage());
TRACE(error.Description().Detach());
return true;
}
return false;
};
auto getValue = [&hResult, &hasFailed](IWbemClassObject *classObject, LPCWSTR property) {
CString propertyValueText = "Not set";
VARIANT propertyValue;
hResult = classObject->Get(property, 0, &propertyValue, 0, 0);
if (!hasFailed()) {
if ((propertyValue.vt == VT_NULL) || (propertyValue.vt == VT_EMPTY)) {
} else if (propertyValue.vt & VT_ARRAY) {
propertyValueText = "Unknown"; //Array types not supported
} else {
propertyValueText = propertyValue.bstrVal;
}
}
VariantClear(&propertyValue);
return propertyValueText;
};
CString manufacturer = "Not set";
CString model = "Not set";
if (!hasFailed()) {
// Connect to the root\cimv2 namespace with the current user and obtain pointer pSvc to make IWbemServices calls.
hResult = locator->ConnectServer(L"ROOT\\CIMV2", nullptr, nullptr, 0, NULL, 0, 0, &services);
if (!hasFailed()) {
// Set the IWbemServices proxy so that impersonation of the user (client) occurs.
hResult = CoSetProxyBlanket(services, RPC_C_AUTHN_WINNT, RPC_C_AUTHZ_NONE, nullptr, RPC_C_AUTHN_LEVEL_CALL,
RPC_C_IMP_LEVEL_IMPERSONATE, nullptr, EOAC_NONE);
if (!hasFailed()) {
IEnumWbemClassObject* classObjectEnumerator = nullptr;
hResult = services->ExecQuery(L"WQL", L"SELECT * FROM Win32_ComputerSystem", WBEM_FLAG_FORWARD_ONLY |
WBEM_FLAG_RETURN_IMMEDIATELY, nullptr, &classObjectEnumerator);
if (!hasFailed()) {
IWbemClassObject *classObject;
ULONG uReturn = 0;
hResult = classObjectEnumerator->Next(WBEM_INFINITE, 1, &classObject, &uReturn);
if (uReturn != 0) {
manufacturer = getValue(classObject, (LPCWSTR)L"Manufacturer");
model = getValue(classObject, (LPCWSTR)L"Model");
}
classObject->Release();
}
classObjectEnumerator->Release();
}
}
}
if (locator) {
locator->Release();
}
if (services) {
services->Release();
}
CoUninitialize();
return { manufacturer, model };
}