[idd] driver: CSettings minor refactor

Document the GNOME permission system for keyboard shortcuts inhibitor
protocol. GNOME stores permissions in flatpak's database even for
non-flatpak applications, which can silently block capture mode.

doc/troubleshooting.rst

@@ -42,3 +42,30 @@ The clipboard is not working
       -  The Spice VDAgent is available in both Spice Guest Tools, and
          standalone as a separate installer. Check your installed programs
          and uninstall the VDAgent if it's installed separately.
+
+.. _keyboard_shortcuts_not_captured_on_gnome_wayland:
+
+Keyboard shortcuts are not captured on GNOME Wayland
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Capture mode may fail to capture compositor shortcuts like
+ALT+Tab or ALT+Middle Mouse - they go to GNOME instead of the guest VM.
+
+When Looking Glass first requests to inhibit shortcuts, GNOME shows a
+dialog asking for permission. If you clicked "Deny" (or dismissed the dialog),
+GNOME permanently blocks the application and never shows the dialog again.
+
+Use the ``flatpak`` command to view or grant the permission, this works even
+if LookingGlass is not a Flatpak application, as GNOME stores these permissions
+in Flatpak's database:
+
+.. code:: bash
+
+   flatpak permission-set gnome shortcuts-inhibitor looking-glass-client.desktop GRANTED
+
+To verify the permission was set:
+
+.. code:: bash
+
+   flatpak permissions gnome shortcuts-inhibitor
+

doc/words.txt

@@ -21,6 +21,7 @@ downsampling
 downscaler
 downscaling
 evdev
+Flatpak
 framebuffer
 fullscreen
 gcc

idd/LGIdd/CSettings.cpp

@@ -83,7 +83,7 @@ void CSettings::SetExtraMode(const DisplayMode& mode)
   RegCloseKey(hKey);
 }
 
-bool CSettings::GetExtraMode(DisplayMode& mode)
+std::wstring CSettings::ReadStringValue(const wchar_t* name, const wchar_t* default)
 {
   HKEY hKey = nullptr;
   LONG ec = RegOpenKeyExW(
@@ -95,29 +95,38 @@ bool CSettings::GetExtraMode(DisplayMode& mode)
   );
 
   if (ec != ERROR_SUCCESS)
-    return false;
+    return std::wstring(default);
 
   DWORD type = 0;
   DWORD cb = 0;
 
-  ec = RegQueryValueExW(hKey, L"ExtraMode", nullptr, &type, nullptr, &cb);
+  ec = RegQueryValueExW(hKey, name, nullptr, &type, nullptr, &cb);
   if (ec != ERROR_SUCCESS || (type != REG_SZ && type != REG_EXPAND_SZ) || cb == 0)
   {
     RegCloseKey(hKey);
-    return false;
+    return std::wstring(default);
   }
 
   std::vector<wchar_t> buf(cb / sizeof(wchar_t) + 1);
-  ec = RegQueryValueExW(hKey, L"ExtraMode", nullptr, &type,
+  ec = RegQueryValueExW(hKey, name, nullptr, &type,
     reinterpret_cast<LPBYTE>(buf.data()), &cb);
   RegCloseKey(hKey);
   if (ec != ERROR_SUCCESS)
-    return false;
+    return  std::wstring(default);
 
   buf.back() = L'\0';
 
   std::wstring s(buf.data());
-  return ParseModeString(s, mode);
+  return s;
+}
+
+bool CSettings::GetExtraMode(DisplayMode& mode)
+{
+  std::wstring extraMode = ReadStringValue(L"ExtraMode", NULL);
+  if (extraMode.empty())
+    return false;
+
+  return ParseModeString(extraMode, mode);
 }
 
 bool CSettings::ReadModesValue(std::vector<std::wstring> &out) const

idd/LGIdd/CSettings.h

@@ -24,6 +24,7 @@ class CSettings
 
   private:
     DisplayModes m_displayModes;
+    std::wstring ReadStringValue(const wchar_t* name, const wchar_t* default);
 
     bool ReadModesValue(std::vector<std::wstring> &out) const;
     bool ParseModeString(const std::wstring& in, DisplayMode& out);

idd/LGIddHelper/CConfigWindow.cpp

@@ -28,7 +28,10 @@ CConfigWindow::CConfigWindow() : m_scale(1)
   if (error != ERROR_SUCCESS)
     DEBUG_ERROR_HR(error, "Failed to load settings");
   else
+  {
     m_modes = m_settings.getModes();
+    m_defaultRefresh = m_settings.getDefaultRefresh();
+  }
 
   if (!CreateWindowEx(0, MAKEINTATOM(s_atom), L"Looking Glass IDD Configuration",
     WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, 500, 400,
@@ -125,6 +128,11 @@ LRESULT CConfigWindow::onCreate()
   m_defRefresh.reset(new CEditWidget(WS_CHILD | WS_VISIBLE | ES_LEFT | ES_NUMBER | WS_TABSTOP, m_hwnd));
   m_defRefreshHz.reset(new CStaticWidget(L"Hz", WS_CHILD | WS_VISIBLE | SS_CENTERIMAGE, m_hwnd));
 
+  if (m_defaultRefresh)
+    m_defRefresh->setNumericValue(*m_defaultRefresh);
+  else
+    m_defRefresh->disable();
+
   RECT client = { 0, 0, (LONG)(436 * m_scale), (LONG)(300 * m_scale) };
   AdjustWindowRect(&client, WS_OVERLAPPEDWINDOW, FALSE);
   SetWindowPos(m_hwnd, NULL, 0, 0, client.right - client.left, client.bottom - client.top, SWP_NOMOVE | SWP_NOZORDER);
@@ -239,5 +247,22 @@ LRESULT CConfigWindow::onCommand(WORD id, WORD code, HWND hwnd)
     updateModeList();
     onModeListSelectChange();
   }
+  else if (hwnd == *m_defRefresh && code == EN_CHANGE && m_defaultRefresh)
+  {
+    int value;
+    try
+    {
+      value = m_defRefresh->getNumericValue();
+    }
+    catch (std::logic_error &)
+    {
+      return 0;
+    }
+
+    m_defaultRefresh = value;
+    LRESULT result = m_settings.setDefaultRefresh(value);
+    if (result != ERROR_SUCCESS)
+      DEBUG_ERROR_HR((HRESULT)result, "Failed to default refresh");
+  }
   return 0;
 }

idd/LGIddHelper/CConfigWindow.h

@@ -42,6 +42,7 @@ class CConfigWindow : public CWindow
   Microsoft::WRL::Wrappers::HandleT<FontTraits> m_font;
   CRegistrySettings m_settings;
   std::optional<std::vector<DisplayMode>> m_modes;
+  std::optional<DWORD> m_defaultRefresh;
 
   void updateFont();
   void updateModeList();

idd/LGIddHelper/CEditWidget.cpp

@@ -24,6 +24,11 @@ int CEditWidget::getNumericValue()
   return std::stoi(getValue());
 }
 
+bool CEditWidget::enable(bool enabled)
+{
+  return Edit_Enable(m_hwnd, enabled);
+}
+
 void CEditWidget::setValue(const std::wstring &value)
 {
   if (!Edit_SetText(m_hwnd, value.c_str()))

idd/LGIddHelper/CEditWidget.h

@@ -9,6 +9,8 @@ public:
   std::wstring getValue();
   int getNumericValue();
 
+  bool enable(bool enabled = true);
+  bool disable() { return enable(false); }
   void setValue(const std::wstring &value);
   void setNumericValue(int value);
 };

idd/LGIddHelper/CRegistrySettings.cpp

@@ -8,6 +8,8 @@
 
 #define LGIDD_REGKEY L"SOFTWARE\\LookingGlass\\IDD"
 
+const DWORD DEFAULT_REFRESH = 120;
+
 CRegistrySettings::CRegistrySettings() : hKey(nullptr) {}
 
 CRegistrySettings::~CRegistrySettings()
@@ -136,3 +138,25 @@ std::wstring DisplayMode::toString()
     serialized.push_back('*');
   return serialized;
 }
+
+std::optional<DWORD> CRegistrySettings::getDefaultRefresh()
+{
+  DWORD result, cbData = sizeof result;
+
+  LSTATUS status = RegGetValue(hKey, nullptr, L"DefaultRefresh", RRF_RT_REG_DWORD, nullptr, &result, &cbData);
+  switch (status)
+  {
+  case ERROR_SUCCESS:
+    return result;
+  case ERROR_FILE_NOT_FOUND:
+    return DEFAULT_REFRESH;
+  default:
+    DEBUG_ERROR_HR(status, "RegGetValue(Modes) length computation");
+    return {};
+  }
+}
+
+LSTATUS CRegistrySettings::setDefaultRefresh(DWORD refresh)
+{
+  return RegSetValueEx(hKey, L"DefaultRefresh", 0, REG_DWORD, (LPBYTE) &refresh, sizeof(DWORD));
+}

idd/LGIddHelper/CRegistrySettings.h

@@ -26,4 +26,7 @@ public:
 
   std::optional<std::vector<DisplayMode>> getModes();
   LSTATUS setModes(const std::vector<DisplayMode> &modes);
+
+  std::optional<DWORD> getDefaultRefresh();
+  LSTATUS setDefaultRefresh(DWORD refresh);
 };