notification: Use interface availability to check for Windows version suitability

Explicit version checks require application manifests on Win10, or an older version will be reported. Check for the toast notification history interface, which is only available on Win10+, and use that to determine if the Windows version is high enough to support notifications.

src/notification/windows/SDL_windowsnotification.c

@@ -95,10 +95,18 @@ static HSTRING hsAppId = NULL;
 static __x_ABI_CWindows_CUI_CNotifications_CIToastNotificationManagerStatics *pToastNotificationManager = NULL;
 static __x_ABI_CWindows_CUI_CNotifications_CIToastNotifier *pToastNotifier = NULL;
 static __x_ABI_CWindows_CUI_CNotifications_CIToastNotificationFactory *pNotificationFactory = NULL;
+static __x_ABI_CWindows_CUI_CNotifications_CIToastNotificationManagerStatics2 *pToastNotificationManagerStatics2 = NULL;
+static __x_ABI_CWindows_CUI_CNotifications_CIToastNotificationHistory *pToastNotificationHistory = NULL;
 
 static WCHAR *app_reg_key = NULL;
 static WCHAR *app_icon_path = NULL;
 
+static enum
+{
+    WIN32_NOTIFICATIONS_INITIALIZATION_FAILED = -1,
+    WIN32_NOTIFICATIONS_UNINITIALIZED = 0,
+    WIN32_NOTIFICATIONS_INITIALIZED = 1
+} initialization_status = WIN32_NOTIFICATIONS_UNINITIALIZED;
 static bool ro_initialized = false;
 static bool co_initialized = false;
 
@@ -459,14 +467,69 @@ static WCHAR *GetAppMetadata(const char *metadata_name)
     return NULL;
 }
 
-static bool InitToastSystem()
+static void QuitToastSystem()
 {
-    static bool initialized = false;
+    if (pToastNotificationHistory) {
+        pToastNotificationHistory->lpVtbl->Release(pToastNotificationHistory);
+        pToastNotificationHistory = NULL;
+    }
+    if (pToastNotificationManagerStatics2) {
+        pToastNotificationManagerStatics2->lpVtbl->Release(pToastNotificationManagerStatics2);
+        pToastNotificationManagerStatics2 = NULL;
+    }
+    if (pNotificationFactory) {
+        pNotificationFactory->lpVtbl->Release(pNotificationFactory);
+        pNotificationFactory = NULL;
+    }
+    if (pToastNotifier) {
+        pToastNotifier->lpVtbl->Release(pToastNotifier);
+        pToastNotifier = NULL;
+    }
+    if (pToastNotificationManager) {
+        pToastNotificationManager->lpVtbl->Release(pToastNotificationManager);
+        pToastNotificationManager = NULL;
+    }
+    if (pClassFactory) {
+        pClassFactory->lpVtbl->Release((IUnknown *)pClassFactory);
+        pClassFactory = NULL;
+    }
+    if (hsAppId) {
+        WIN_WindowsDeleteString(hsAppId);
+        hsAppId = NULL;
+    }
+    if (hsGroupId) {
+        WIN_WindowsDeleteString(hsGroupId);
+        hsGroupId = NULL;
+    }
+
+    CleanupIcons();
+
+    if (ro_initialized) {
+        WIN_RoUninitialize();
+        ro_initialized = false;
+    }
+    if (co_initialized) {
+        WIN_CoUninitialize();
+        co_initialized = false;
+    }
+
+    SDL_free(app_reg_key);
+    app_reg_key = NULL;
 
-    if (initialized) {
-        return true;
+    SDL_free(app_icon_path);
+    app_icon_path = NULL;
+}
+
+static bool InitToastSystem()
+{
+    // Only try to initialize once.
+    if (initialization_status != WIN32_NOTIFICATIONS_UNINITIALIZED) {
+        return initialization_status == WIN32_NOTIFICATIONS_INITIALIZED;
     }
 
+    // Failure of anything results in an early-out, so the initial value is failure.
+    initialization_status = WIN32_NOTIFICATIONS_INITIALIZATION_FAILED;
+
 #define RESOLVE(x)                                \
     WIN_##x = (x##_t)WIN_LoadComBaseFunction(#x); \
     if (!WIN_##x)                                 \
@@ -568,7 +631,18 @@ static bool InitToastSystem()
         goto cleanup;
     }
 
-    initialized = true;
+    // This acts as a version check, as notification history is only available on Win10+.
+    hr = pToastNotificationManager->lpVtbl->QueryInterface(pToastNotificationManager, &IID_IToastNotificationManagerStatics2, (LPVOID *)&pToastNotificationManagerStatics2);
+    if (FAILED(hr)) {
+        goto cleanup;
+    }
+
+    hr = pToastNotificationManagerStatics2->lpVtbl->get_History(pToastNotificationManagerStatics2, &pToastNotificationHistory);
+    if (FAILED(hr)) {
+        goto cleanup;
+    }
+
+    initialization_status = WIN32_NOTIFICATIONS_INITIALIZED;
 
 cleanup:
     WIN_WindowsDeleteString(hsToastNotificationManager);
@@ -577,7 +651,11 @@ cleanup:
     SDL_free(app_id);
     SDL_free(app_name);
 
-    return initialized;
+    if (initialization_status == WIN32_NOTIFICATIONS_INITIALIZATION_FAILED) {
+        QuitToastSystem();
+    }
+
+    return initialization_status == WIN32_NOTIFICATIONS_INITIALIZED;
 }
 
 static bool AppendXmlAudio(SDL_IOStream *dst, const char *sound)
@@ -860,23 +938,12 @@ done:
 
 static void ClearNotificationWithID(SDL_NotificationID id)
 {
-    __x_ABI_CWindows_CUI_CNotifications_CIToastNotificationHistory *pToastNotificationHistory = NULL;
-    __x_ABI_CWindows_CUI_CNotifications_CIToastNotificationManagerStatics2 *pToastNotificationManagerStatics2 = NULL;
     HSTRING_HEADER hshTag;
     HSTRING hsTag = NULL;
     WCHAR tag[32];
 
-    HRESULT hr = pToastNotificationManager->lpVtbl->QueryInterface(pToastNotificationManager, &IID_IToastNotificationManagerStatics2, (LPVOID *)&pToastNotificationManagerStatics2);
-    if (FAILED(hr)) {
-        return;
-    }
-    hr = pToastNotificationManagerStatics2->lpVtbl->get_History(pToastNotificationManagerStatics2, &pToastNotificationHistory);
-    if (FAILED(hr)) {
-        goto cleanup;
-    }
-
     SDL_swprintf(tag, SDL_arraysize(tag), L"%" SDL_PRIu32, id);
-    hr = WIN_WindowsCreateStringReference(tag, (UINT32)SDL_wcslen(tag), &hshTag, &hsTag);
+    HRESULT hr = WIN_WindowsCreateStringReference(tag, (UINT32)SDL_wcslen(tag), &hshTag, &hsTag);
     if (FAILED(hr)) {
         goto cleanup;
     }
@@ -885,15 +952,9 @@ static void ClearNotificationWithID(SDL_NotificationID id)
 
 cleanup:
     WIN_WindowsDeleteString(hsTag);
-    if (pToastNotificationHistory) {
-        pToastNotificationHistory->lpVtbl->Release(pToastNotificationHistory);
-    }
-    if (pToastNotificationManagerStatics2) {
-        pToastNotificationManagerStatics2->lpVtbl->Release(pToastNotificationManagerStatics2);
-    }
 }
 
-NTSTATUS WIN_BCryptGenRandom(BCRYPT_ALG_HANDLE hAlgorithm, PUCHAR pbBuffer, ULONG cbBuffer, ULONG dwFlags)
+static NTSTATUS WIN_BCryptGenRandom(BCRYPT_ALG_HANDLE hAlgorithm, PUCHAR pbBuffer, ULONG cbBuffer, ULONG dwFlags)
 {
     static bool s_bLoaded;
     static HMODULE s_hBCrypt;
@@ -920,13 +981,8 @@ SDL_NotificationID SDL_SYS_ShowNotification(SDL_PropertiesID props)
     SDL_NotificationID ret = 0;
 
     // Need Win10 or higher for notifications.
-    if (!WIN_IsWindows10OrGreater()) {
-        SDL_SetError("Notifications require Windows 10 or higher");
-        return 0;
-    }
-
     if (!InitToastSystem()) {
-        SDL_CleanupNotifications();
+        SDL_SetError("Failed to initialize the notification system (requires Windows 10 or higher)");
         return 0;
     }
 
@@ -1101,8 +1157,8 @@ cleanup:
 
 bool SDL_RemoveNotification(SDL_NotificationID notification)
 {
-    if (!WIN_IsWindows10OrGreater()) {
-        return SDL_Unsupported();
+    if (!InitToastSystem()) {
+        return SDL_SetError("Failed to initialize the notification system (requires Windows 10 or higher)");
     }
 
     ClearNotificationWithID(notification);
@@ -1111,51 +1167,12 @@ bool SDL_RemoveNotification(SDL_NotificationID notification)
 
 void SDL_CleanupNotifications(void)
 {
-    if (pNotificationFactory) {
-        pNotificationFactory->lpVtbl->Release(pNotificationFactory);
-        pNotificationFactory = NULL;
-    }
-    if (pToastNotifier) {
-        pToastNotifier->lpVtbl->Release(pToastNotifier);
-        pToastNotifier = NULL;
-    }
-    if (pToastNotificationManager) {
-        pToastNotificationManager->lpVtbl->Release(pToastNotificationManager);
-        pToastNotificationManager = NULL;
-    }
-    if (pClassFactory) {
-        pClassFactory->lpVtbl->Release((IUnknown *)pClassFactory);
-        pClassFactory = NULL;
-    }
-    if (hsAppId) {
-        WIN_WindowsDeleteString(hsAppId);
-        hsAppId = NULL;
-    }
-    if (hsGroupId) {
-        WIN_WindowsDeleteString(hsGroupId);
-        hsGroupId = NULL;
-    }
-
-    CleanupIcons();
-
-    if (ro_initialized) {
-        WIN_RoUninitialize();
-        ro_initialized = false;
-    }
-    if (co_initialized) {
-        WIN_CoUninitialize();
-        co_initialized = false;
-    }
-
-    SDL_free(app_reg_key);
-    app_reg_key = NULL;
-
-    SDL_free(app_icon_path);
-    app_icon_path = NULL;
+    QuitToastSystem();
+    initialization_status = WIN32_NOTIFICATIONS_UNINITIALIZED;
 }
 
 bool SDL_RequestNotificationPermission(void)
 {
     // Notifications are supported on Win10 or higher.
-    return (bool)WIN_IsWindows10OrGreater();
+    return InitToastSystem();
 }