Getting BLE Beacons in C++ Windows 10 Desktop Application - c++

Has someone already figured out how to get BLE Beacons into a c++ desktop apps?
I have some code from the following websites to get it done in c#:
msdn sozial site
and
codefest.at post. Sorry, it's in german but the code is code
but that'for C# and not c++
I also have the example from MS (msdn.microsoft.com/en-us/library/hh973459.aspx) how to use the WinRL
For now I have the following code:
#include "stdafx.h"
#include <iostream>
#include <Windows.Foundation.h>
#include <wrl\wrappers\corewrappers.h>
#include <wrl\client.h>
#include <stdio.h>
#include <../winrt/windows.devices.bluetooth.h>
#include <../winrt/windows.devices.bluetooth.advertisement.h>
using namespace std;
using namespace Microsoft::WRL;
using namespace Microsoft::WRL::Wrappers;
using namespace ABI::Windows::Foundation;
using namespace ABI::Windows::Devices::Bluetooth::Advertisement;
/* http://www.codefest.at/post/2015/09/07/Bluetooth-Beacons-Windows-10.aspx
private async void WatcherOnReceived(BluetoothLEAdvertisementWatcher sender, BluetoothLEAdvertisementReceivedEventArgs eventArgs)
{
_beaconManager.ReceivedAdvertisement(eventArgs);
}
var watcher = new BluetoothLEAdvertisementWatcher { ScanningMode = BluetoothLEScanningMode.Active };
watcher.Received += WatcherOnReceived;
watcher.Stopped += WatcherOnStopped;
watcher.Start();
*/
// Prints an error string for the provided source code line and HRESULT
// value and returns the HRESULT value as an int.
int PrintError(unsigned int line, HRESULT hr)
{
wprintf_s(L"ERROR: Line:%d HRESULT: 0x%X\n", line, hr);
return hr;
}
EventRegistrationToken watcherToken;
int main()
{
// Initialize the Windows Runtime.
RoInitializeWrapper initialize(RO_INIT_MULTITHREADED);
if (FAILED(initialize))
{
return PrintError(__LINE__, initialize);
}
// Get the activation factory for the IBluetoothLEAdvertisementWatcherFactory interface.
ComPtr<IBluetoothLEAdvertisementWatcherFactory> bleAdvWatcherFactory;
HRESULT hr = GetActivationFactory(HStringReference(RuntimeClass_Windows_Devices_Bluetooth_Advertisement_BluetoothLEAdvertisementWatcher).Get(), &bleAdvWatcherFactory);
if (FAILED(hr))
{
return PrintError(__LINE__, hr);
}
IBluetoothLEAdvertisementWatcher* bleWatcher;
IBluetoothLEAdvertisementFilter* bleFilter;
hr = bleAdvWatcherFactory->Create(bleFilter, &bleWatcher);
if (bleWatcher == NULL)
{
cout << "bleWatcher is NULL, err is " << hex << hr;
}
else
{
bleWatcher->Start();
while (1)
Sleep(1000);
}
return 0;
}
my problem is that the Watcher Factory complains ( hr = E_INVALIDARG "One or more arguments are not valid" 0x80070057) that one of the variables is not valid (I suspect the filter because it has no valid content).
And even on the same level of severity, I have no idea how to register the event handler for the incoming beacons.
msdn.microsoft.com/en-us/library/windows/apps/windows.devices.bluetooth.advertisement.bluetoothleadvertisementwatcher.received?cs-save-lang=1&cs-lang=cpp
is telling me something about the Received event. But I don't have it in my autocomplete from VS and also not by manually looking into the header file.
The next best thing I have is the "add_Received" but I can't find any documentation about it how to use. And I don't get that much wiser from the header file.
Thanks in advance for tips and tricks or even a working solution.
Markus

You have few problems in your code. First of all All I* classes should be wrapped around ComPtr<I*>
ComPtr<IBluetoothLEAdvertisementWatcher> bleWatcher;
ComPtr<IBluetoothLEAdvertisementFilter> bleFilter;
In function bleAdvWatcherFactory->Create(bleFilter, &bleWatcher); parameter bleFilter is undefined and it will lead to undefined behaviour (In Debug version it might be initialized as nullptr).
You can create it by using:
Wrappers::HStringReference
Wrappers::HStringReference class_id_filter(RuntimeClass_Windows_Devices_Bluetooth_Advertisement_BluetoothLEAdvertisementFilter);
hr = RoActivateInstance(class_id_filter.Get(), reinterpret_cast<IInspectable**>(bleFilter.GetAddressOf()));
Then you are allowed to call:
hr = bleAdvWatcherFactory->Create(bleFilter.Get(), &bleWatcher.GetAddressOf());

Related

How do you identify "File Explorer" instances in an `IShellWindows` collection?

I'm trying to get a list of all "File Explorer" instances currently running. It's fairly straight forward getting a list that includes all instances, but I find myself running into a brick wall filtering that list to only "File Explorer" instances.
The following piece of code retrieves all Explorer instances, meaning both "File Explorer" and "Internet Explorer":
#include <comdef.h>
#include <ExDisp.h>
#include <ShlGuid.h>
#include <Windows.h>
#include <cstdio>
using _com_util::CheckError;
using std::puts;
_COM_SMARTPTR_TYPEDEF(IShellWindows, __uuidof(IShellWindows));
int main()
{
CheckError(::CoInitializeEx(nullptr, COINIT_APARTMENTTHREADED | COINIT_DISABLE_OLE1DDE));
// Acquire IShellWindows interface
IShellWindowsPtr spShellWindows{};
CheckError(spShellWindows.CreateInstance(CLSID_ShellWindows, nullptr, CLSCTX_LOCAL_SERVER));
// Request iterator
IUnknownPtr spEnum{};
CheckError(spShellWindows->_NewEnum(&spEnum));
IEnumVARIANTPtr spEnumVariant{};
CheckError(spEnum.QueryInterface(__uuidof(spEnumVariant), &spEnumVariant));
// Iterate over shell windows ...
while (true) {
variant_t var{};
// ... one element at a time
HRESULT hr = spEnumVariant->Next(1, &var, nullptr);
CheckError(hr);
// Iterator depleted?
if (hr == S_FALSE) break;
// Did we get the expected `IDispatch` interface?
if (var.vt != VT_DISPATCH) continue;
IDispatchPtr spDisp{};
spDisp.Attach(var.pdispVal, true);
puts("Got suspect; need ID");
// That was easy; now on to some real challenges
}
}
The obvious attempt
My first take at the problem was to just get rid of everything that isn't "File Explorer". Asking for the IWebBrowser2 interface would certainly only get an affirmative response from objects that actually are web browsers. Adding the following to the code above:
_COM_SMARTPTR_TYPEDEF(IWebBrowser2, __uuidof(IWebBrowser2));
// ...
int main()
{
// ...
IWebBrowser2Ptr spWebBrowser{};
hr = spDisp.QueryInterface(__uuidof(spWebBrowser), &spWebBrowser);
if (SUCCEEDED(hr)) puts("Implements IWebBrowser2");
// ...
After making the changes and running the code while an "Internet Explorer" instance is running produces the desired output. However, running the code while a "File Explorer" instance is running produces the same output! That's a surprise and a disappointment, all at the same time.
More robust, less useful
Exluding objects that can be identified as "not File Explorer" didn't work out. Let's try to only include objects that can be identified as "File Explorer" instead. That sounds even more obvious, but as we've learned, "obvious" and "not" go hand in hand when it comes to the Windows Shell.
I haven't actually implemented this, but the IShellWindows interface provides an Item method that can return only objects that match a particular ShellWindowTypeConstants (e.g. SWC_EXPLORER or SWC_BROWSER). Or return an object at a particular index in the window collection. But not BOTH!
So, yes, (potentially) more robust, but also less useful as it doesn't meet my requirements as soon as more than one instances of "File Explorer" are running. Bummer.
Circumstantial evidence
While neither of the above led anywhere, I started over and went on a full-blown investigation looking for hints. Since "File Explorer" browses the Shell namespace, there may be something to that account. The following outlines the approach, based on an article by Raymond Chen titled A big little program: Monitoring Internet Explorer and Explorer windows, part 1: Enumeration:
Starting from the IDispatch interface above, ask for a service with ID SID_STopLevelBrowser to get an IShellBrowser interface.
Call IShellBrowser::QueryActiveShellView to get an IShellView interface.
Ask the IShellView whether it implements something Shell-namespace-y, e.g. IPersistIDList.
If it does, conclude that we're holding a reference to a "File Explorer" instance.
This appears to produce the desired result, though it's not clear to me future-proof this is or when it stops working. Leaving aside how overly convoluted this appears, I'm concerned about its reliability.
Question
What's the recommended/robust/reliable way to identify all "File Explorer" instances in an IShellWindows collection? I will favor solutions based on official documentation, though I understand that this is the Windows Shell and there's next to no documentation at all.
Here's a possibility ...
#include <comdef.h>
#include <ExDisp.h>
#include <ShlGuid.h>
#include <Windows.h>
#include <cstdio>
#include <atlbase.h>
#include <string>
using _com_util::CheckError;
using std::puts;
using std::string;
_COM_SMARTPTR_TYPEDEF(IShellWindows, __uuidof(IShellWindows));
//nicked from StackOverflow
std::string ProcessIdToName(DWORD_PTR processId)
{
std::string ret;
HANDLE handle = OpenProcess(
PROCESS_QUERY_LIMITED_INFORMATION,
FALSE,
processId /* This is the PID, you can find one from windows task manager */
);
if (handle)
{
DWORD buffSize = 1024;
CHAR buffer[1024];
if (QueryFullProcessImageNameA(handle, 0, buffer, &buffSize))
{
ret = buffer;
}
else
{
printf("Error GetModuleBaseNameA : %lu", GetLastError());
}
CloseHandle(handle);
}
else
{
printf("Error OpenProcess : %lu", GetLastError());
}
return ret;
}
int main()
{
CheckError(::CoInitializeEx(nullptr, COINIT_APARTMENTTHREADED | COINIT_DISABLE_OLE1DDE));
// Acquire IShellWindows interface
IShellWindowsPtr spShellWindows{};
CheckError(spShellWindows.CreateInstance(CLSID_ShellWindows, nullptr, CLSCTX_LOCAL_SERVER));
// Request iterator
IUnknownPtr spEnum{};
CheckError(spShellWindows->_NewEnum(&spEnum));
IEnumVARIANTPtr spEnumVariant{};
CheckError(spEnum.QueryInterface(__uuidof(spEnumVariant), &spEnumVariant));
// Iterate over shell windows ...
while (true) {
variant_t var{};
// ... one element at a time
HRESULT hr = spEnumVariant->Next(1, &var, nullptr);
CheckError(hr);
// Iterator depleted?
if (hr == S_FALSE) break;
// Did we get the expected `IDispatch` interface?
if (var.vt != VT_DISPATCH) continue;
IDispatchPtr spDisp{};
spDisp.Attach(var.pdispVal, true);
puts("Got suspect; need ID");
// That was easy; now on to some real challenges
CComPtr<IWebBrowser2> lpWB;
spDisp->QueryInterface(&lpWB);
SHANDLE_PTR hWnd{ 0 };
lpWB->get_HWND(&hWnd);
if (hWnd)
{
DWORD pid = 0;
GetWindowThreadProcessId((HWND)hWnd, &pid);
if (pid != 0)
{
puts("pid");
auto s = ProcessIdToName((DWORD_PTR)pid);
puts(s.c_str());
}
}
}
}

How to get a human readable process name (like in the task manager) via Win32 API? [duplicate]

I want to get the description of a process (the description that is seen in task manager) in Windows using C++.
You most likely want to get the FileDesription field from the version resources of the main .exe file of the program, using the VerQueryValue() API call. Here is an example from that document:
The following example shows how to enumerate the available version languages and retrieve the FileDescription string-value for each language.
Be sure to call the GetFileVersionInfoSize and GetFileVersionInfo functions before calling VerQueryValue to properly initialize the pBlock buffer.
// Structure used to store enumerated languages and code pages.
HRESULT hr;
struct LANGANDCODEPAGE {
WORD wLanguage;
WORD wCodePage;
} *lpTranslate;
// Read the list of languages and code pages.
VerQueryValue(pBlock,
TEXT("\\VarFileInfo\\Translation"),
(LPVOID*)&lpTranslate,
&cbTranslate);
// Read the file description for each language and code page.
for( i=0; i < (cbTranslate/sizeof(struct LANGANDCODEPAGE)); i++ )
{
hr = StringCchPrintf(SubBlock, 50,
TEXT("\\StringFileInfo\\%04x%04x\\FileDescription"),
lpTranslate[i].wLanguage,
lpTranslate[i].wCodePage);
if (FAILED(hr))
{
// TODO: write error handler.
}
// Retrieve file description for language and code page "i".
VerQueryValue(pBlock,
SubBlock,
&lpBuffer,
&dwBytes);
}
Although I read this question, the accepted answer, and the documentation for VerQueryValue, I spent quite a while to understand how to use that VerQueryValue function (since the code example in the docs has no declarations of variables and isn't clear for me at all).
So I decided to put here the code that can be easily run as a working example of the usage of VerQueryValue to get a process description.
#pragma comment(lib,"Version.lib")
#include <iostream>
#include <windows.h>
#include <winver.h>
using namespace std;
int printFileDescriptions(const wchar_t* filename)
{
int versionInfoSize = GetFileVersionInfoSize(filename, NULL);
if (!versionInfoSize) {
return 0;
}
auto versionInfo = new BYTE[versionInfoSize];
std::unique_ptr<BYTE[]> versionInfo_automatic_cleanup(versionInfo);
if (!GetFileVersionInfo(filename, NULL, versionInfoSize, versionInfo)) {
return 0;
}
struct LANGANDCODEPAGE {
WORD wLanguage;
WORD wCodePage;
} *translationArray;
UINT translationArrayByteLength = 0;
if (!VerQueryValue(versionInfo, L"\\VarFileInfo\\Translation", (LPVOID*)&translationArray, &translationArrayByteLength)) {
return 0;
}
// You may check GetSystemDefaultUILanguage() == translationArray[i].wLanguage
// if only the system language required
for (unsigned int i = 0; i < (translationArrayByteLength / sizeof(LANGANDCODEPAGE)); i++) {
wchar_t fileDescriptionKey[256];
wsprintf(
fileDescriptionKey,
L"\\StringFileInfo\\%04x%04x\\FileDescription",
translationArray[i].wLanguage,
translationArray[i].wCodePage
);
wchar_t* fileDescription = NULL;
UINT fileDescriptionSize;
if (VerQueryValue(versionInfo, fileDescriptionKey, (LPVOID*)&fileDescription, &fileDescriptionSize)) {
wcout << endl << fileDescription << endl;
}
}
return TRUE;
}
int main()
{
// Set locale of the console to print non-ASCII symbols
SetConsoleOutputCP(GetACP());
SetConsoleCP(GetACP());
wcout.imbue(std::locale("")); // set default global locale
// ----------------------------------------------------
auto path = L"C:\\Windows\\explorer.exe";
printFileDescriptions(path);
wcin.get(); // to prevent console close
}
It's supposed that all WinAPI functions on your system use wchar_t, that is VerQueryValueW is actually used.
The initial version of the code I took here Retrieve File Description an Application VerQueryValue

C++ code: Logical error in finding the Kinect sensor

I want to get depth and RGB data from Kinect V2 by Windows SDK 2.0 in Viual Studio 2013. So I write these codes:
#include <Kinect.h>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <Windows.h>
#include <iostream>
using namespace std;
const int width = 512;
const int height = 424;
const int colorwidth = 1920;
const int colorheight = 1080;
// Kinect Variables
IKinectSensor* sensor; // Kinect sensor
IMultiSourceFrameReader* reader; // Kinect data source
ICoordinateMapper* mapper;
int main(int argc, char* argv[]) {
if (FAILED(GetDefaultKinectSensor(&sensor))) {
printf("not found sensor");
getchar();
return -100;
}
if (sensor) {
sensor->get_CoordinateMapper(&mapper);
sensor->Open();
sensor->OpenMultiSourceFrameReader(
FrameSourceTypes::FrameSourceTypes_Depth | FrameSourceTypes::FrameSourceTypes_Color,
&reader);
IMultiSourceFrame* framesource;
cout << "Find!!!";
getchar();
return 100;
}
else {
return -100;
}
getchar();
return 10;
}
Logically, when I do not plug Kinect sensor to my Laptop, in Console should be printed: "not found sensor",isn't it? But, in console printed: "Find!!!". what is the problem?
No, Since SDK v2, You can debug an application by using KinectStudio, even without a physical kinect is connected to the system. If you want to check whether the actual Kinect is connected, you need to use IsAvailable property of the sensor itself. GetDefaultKinectSensor will always give you S_OK unless you have runtime or installation issues. GetDefaultKinectSensor won't check whether is this stream comes from actual physical kinect sensor or from KinectStudio.
The following is a code snippet from my project. If you want more examples about Kinect, please refer my project in github https://github.com/shanilfernando/VRInteraction or comment here. I'm more than happy to help you.
HRESULT CDepthBasics::InitializeDefaultSensor()
{
HRESULT hr;
hr = GetDefaultKinectSensor(&m_pKinectSensor);
if (FAILED(hr))
{
return hr;
}
if (m_pKinectSensor)
{
if (SUCCEEDED(hr))
{
hr = m_pKinectSensor->get_CoordinateMapper(&m_pCoordinateMapper);
}
if (SUCCEEDED(hr))
{
hr = m_pKinectSensor->Open();
}
if (SUCCEEDED(hr))
{
hr = m_pKinectSensor->OpenMultiSourceFrameReader(
FrameSourceTypes::FrameSourceTypes_Depth | FrameSourceTypes::FrameSourceTypes_Color | FrameSourceTypes::FrameSourceTypes_Body | FrameSourceTypes::FrameSourceTypes_BodyIndex,
&m_pMultiSourceFrameReader);
}
}
if (!m_pKinectSensor || FAILED(hr))
{
std::cout << "No ready Kinect found!" << std::endl;
return E_FAIL;
}
else
{
std::cout << "Kinect found!" << std::endl;
}
return hr;
}
https://github.com/shanilfernando/VRInteraction/blob/master/DepthBasics.cpp
Edit
I didn't use IsAvailable since it doesn't matter for me where that stream comes from. Sometimes I used KinectStudio to get the streams while Kinect is not with me. I said GetDefaultKinectSensor will return S_OK unless you have runtime or installation issues, I did NOT said GetDefaultKinectSensor will always give you a valid m_pKinectSensor. Since we don't have access to the implementation of the GetDefaultKinectSensor and as a good practice, it is better to check it null or not before using it. This is the official answer for your question from the Microsoft

get_accChildCount returns 0 when it shouldn't

I'm trying to enumerate tabs of IE from an extension and from a standalone application. For one of the MSAA nodes get_accChildCount returns 0 when called from extension, while it should return 1 according to inspect and a call from standalone application.
The problem was described previously at StackOverflow, yet it was solved via a hack that doesn't work for me. /clr and /MT are incompatible.
Also there was a topic on MSDN with the same issue. There's no single answer there.
If you run IE with administrator privileges, it works properly.
API Monitor shows several thousand calls in a minimal example, and it's unclear which of these are related. The minimal example is attached below.
What are the undocumented cases when get_accChildCount returns wrong child count?
What other method could I use to activate the tab by URL in most versions of IE?
#include <atlbase.h>
#include <atlcom.h>
#include <atlctl.h>
#include <atltypes.h>
#include <atlsafe.h>
#include <io.h>
#include <fcntl.h>
#include <windows.h>
#include <iostream>
#include <string>
#include <vector>
#include <boost/format.hpp>
#include <fstream>
using namespace std;
CComPtr<IAccessible> get_acc_by_hwnd(HWND hwnd) {
CComPtr<IAccessible> ret;
HRESULT hr = ::AccessibleObjectFromWindow(hwnd, OBJID_WINDOW, IID_IAccessible, (void**) &ret);
if (FAILED(hr) || !ret) {
wcout << L"Accessible::Accessible invalid hwnd" << endl;
}
return ret;
}
std::vector<CComPtr<IAccessible>> get_acc_children(CComPtr<IAccessible> acc) {
std::vector<CComPtr<IAccessible>> ret;
long count;
if (FAILED(acc->get_accChildCount(&count))) return ret;
long count_obtained = 0;
if (!count) return ret;
std::vector<CComVariant> accessors(count);
if (FAILED(::AccessibleChildren(acc, 0, count, &*accessors.begin(), &count_obtained))) return ret;
accessors.resize(count_obtained);
for (auto vtChild : accessors) {
if (vtChild.vt != VT_DISPATCH) continue;
CComQIPtr<IAccessible> pChild = vtChild.pdispVal;
if (pChild) ret.push_back(pChild);
}
return ret;
}
bool is_client(CComPtr<IAccessible> acc) {
CComVariant var;
HRESULT hr = acc->get_accRole(CComVariant(CHILDID_SELF), &var);
return SUCCEEDED(hr) && var.vt == VT_I4 && var.lVal == 0xA;
}
std::wstring get_descr(CComPtr<IAccessible> acc) {
CComBSTR str;
HRESULT hr = acc->get_accDescription(CComVariant(CHILDID_SELF), &str);
return SUCCEEDED(hr) && str ? std::wstring(str) : L"";
}
int main() {
::CoInitialize(nullptr);
_setmode(_fileno(stdout), _O_U16TEXT);
// put HWND of the window that contains tab labels
// it's hardcoded to minimize quantity of API calls
HWND hwnd = reinterpret_cast<HWND>(0x002D0696);
CComPtr<IAccessible> iaccessible;
HRESULT hr = ::AccessibleObjectFromWindow(hwnd, OBJID_WINDOW, IID_IAccessible, (void**) &iaccessible);
if (FAILED(hr) || !iaccessible) {
wcout << L"AccessibleBrowser::activate_tab " L"failed to get IAccessible for IE" << endl;
return EXIT_FAILURE;
}
wstring const sentinel = L"\r\n";
for (auto child : get_acc_children(iaccessible)) if (is_client(child)) {
for (auto child1 : get_acc_children(child)) { // fails here in extension
for (auto child2 : get_acc_children(child1)) {
std::wstring descr = get_descr(child2);
auto pos = descr.find(sentinel);
if (pos == string::npos) continue;
auto tab_url = descr.substr(pos + sentinel.size());
wcout << tab_url << endl;
}
}
}
}
I poked at your program for a while without having much to show for it. Perhaps I realized too late that it was not supposed to reproduce the problem :( I can only provide some possibly helpful hints to get you to look under the right kind of rock.
yet it was solved via a hack that doesn't work for me
These programmers made a simple mistake, they forgot to call CoInitialize/Ex(). A very common oversight. Using the /clr build option works around that mistake because it is now the CLR that calls it. You can easily repro this mishap, just comment out the CoInitialize() call. Unfortunately it works for a while without any loud errors being produced, but you do get 0 for certain accobjects. You'll notice your program no longer finds the tabs.
Not so sure I can cleanly explain this, certain COM-style object models don't actually use the COM infrastructure. DirectX is the best example, we can add UIAutomation to that list. I assume it will silently fail like this when the client app's component is COM-based. Unclear if it is, DirectUIHWnd is quite undocumented.
So stop looking for that as a workaround, you did not forget to call CoInitialize() and it will be taken care of by IE before it activates your extension.
If you run IE with administrator privileges, it works properly.
That's a better rock. Many programmers run VS elevated all the time, the roles might be reversed in the case of UIA. Do keep in mind that your extension runs in a sandbox inside IE. No real idea how elevating IE affects this. One thing you cannot do from code running in the low-integrity sandbox is poke at UI components owned by a code that runs in a higher integrity mode. Google "disable IE enhanced protected mode" and follow the guideline to see what effect that has on your addin.

How to get process description?

I want to get the description of a process (the description that is seen in task manager) in Windows using C++.
You most likely want to get the FileDesription field from the version resources of the main .exe file of the program, using the VerQueryValue() API call. Here is an example from that document:
The following example shows how to enumerate the available version languages and retrieve the FileDescription string-value for each language.
Be sure to call the GetFileVersionInfoSize and GetFileVersionInfo functions before calling VerQueryValue to properly initialize the pBlock buffer.
// Structure used to store enumerated languages and code pages.
HRESULT hr;
struct LANGANDCODEPAGE {
WORD wLanguage;
WORD wCodePage;
} *lpTranslate;
// Read the list of languages and code pages.
VerQueryValue(pBlock,
TEXT("\\VarFileInfo\\Translation"),
(LPVOID*)&lpTranslate,
&cbTranslate);
// Read the file description for each language and code page.
for( i=0; i < (cbTranslate/sizeof(struct LANGANDCODEPAGE)); i++ )
{
hr = StringCchPrintf(SubBlock, 50,
TEXT("\\StringFileInfo\\%04x%04x\\FileDescription"),
lpTranslate[i].wLanguage,
lpTranslate[i].wCodePage);
if (FAILED(hr))
{
// TODO: write error handler.
}
// Retrieve file description for language and code page "i".
VerQueryValue(pBlock,
SubBlock,
&lpBuffer,
&dwBytes);
}
Although I read this question, the accepted answer, and the documentation for VerQueryValue, I spent quite a while to understand how to use that VerQueryValue function (since the code example in the docs has no declarations of variables and isn't clear for me at all).
So I decided to put here the code that can be easily run as a working example of the usage of VerQueryValue to get a process description.
#pragma comment(lib,"Version.lib")
#include <iostream>
#include <windows.h>
#include <winver.h>
using namespace std;
int printFileDescriptions(const wchar_t* filename)
{
int versionInfoSize = GetFileVersionInfoSize(filename, NULL);
if (!versionInfoSize) {
return 0;
}
auto versionInfo = new BYTE[versionInfoSize];
std::unique_ptr<BYTE[]> versionInfo_automatic_cleanup(versionInfo);
if (!GetFileVersionInfo(filename, NULL, versionInfoSize, versionInfo)) {
return 0;
}
struct LANGANDCODEPAGE {
WORD wLanguage;
WORD wCodePage;
} *translationArray;
UINT translationArrayByteLength = 0;
if (!VerQueryValue(versionInfo, L"\\VarFileInfo\\Translation", (LPVOID*)&translationArray, &translationArrayByteLength)) {
return 0;
}
// You may check GetSystemDefaultUILanguage() == translationArray[i].wLanguage
// if only the system language required
for (unsigned int i = 0; i < (translationArrayByteLength / sizeof(LANGANDCODEPAGE)); i++) {
wchar_t fileDescriptionKey[256];
wsprintf(
fileDescriptionKey,
L"\\StringFileInfo\\%04x%04x\\FileDescription",
translationArray[i].wLanguage,
translationArray[i].wCodePage
);
wchar_t* fileDescription = NULL;
UINT fileDescriptionSize;
if (VerQueryValue(versionInfo, fileDescriptionKey, (LPVOID*)&fileDescription, &fileDescriptionSize)) {
wcout << endl << fileDescription << endl;
}
}
return TRUE;
}
int main()
{
// Set locale of the console to print non-ASCII symbols
SetConsoleOutputCP(GetACP());
SetConsoleCP(GetACP());
wcout.imbue(std::locale("")); // set default global locale
// ----------------------------------------------------
auto path = L"C:\\Windows\\explorer.exe";
printFileDescriptions(path);
wcin.get(); // to prevent console close
}
It's supposed that all WinAPI functions on your system use wchar_t, that is VerQueryValueW is actually used.
The initial version of the code I took here Retrieve File Description an Application VerQueryValue