Add native platform interface for usb storage events

Allows native interfaces to send a signal when a USB storage device
is inserted/removed

Refs #14481

src/app/qgisapp.cpp

@@ -1321,8 +1321,11 @@ QgisApp::QgisApp( QSplashScreen *splash, bool restorePlugins, bool skipVersionCh
   QgsGui::instance()->nativePlatformInterface()->initializeMainWindow( windowHandle(),
       QgsApplication::applicationName(),
       QgsApplication::organizationName(),
-      Qgis::QGIS_VERSION
-                                                                     );
+      Qgis::QGIS_VERSION );
+  connect( QgsGui::instance()->nativePlatformInterface(), &QgsNative::usbStorageNotification, this, [ = ]( const QString & path, bool inserted )
+  {
+    QgsDebugMsg( QStringLiteral( "USB STORAGE NOTIFICATION! %1 %2" ).arg( path ).arg( inserted ? QStringLiteral( "inserted" ) : QStringLiteral( "removed" ) ) );
+  } );
 
   // setup application progress reports from task manager
   connect( QgsApplication::taskManager(), &QgsTaskManager::taskAdded, this, []

src/native/CMakeLists.txt

@@ -36,6 +36,10 @@ SET(QGIS_NATIVE_SRCS
   qgsnative.cpp
 )
 
+SET (QGIS_NATIVE_MOC_HDRS
+  qgsnative.h
+)
+
 IF(APPLE)
   SET(QGIS_APP_OBJC_SRCS
     mac/cocoainitializer.mm
@@ -54,6 +58,10 @@ IF(WIN32)
     ../../external/wintoast/src/wintoastlib.cpp
     win/qgswinnative.cpp
   )
+  SET (QGIS_NATIVE_MOC_HDRS
+    ${QGIS_NATIVE_MOC_HDRS}
+    win/qgswinnative.h
+  )
   SET(QGIS_NATIVE_SRCS ${QGIS_NATIVE_SRCS}
     ${QGIS_APP_WIN32_SRCS}
   )
@@ -72,6 +80,8 @@ SET(QGIS_NATIVE_HDRS
   qgsnative.h
 )
 
+QT5_WRAP_CPP(QGIS_NATIVE_MOC_SRCS ${QGIS_NATIVE_MOC_HDRS})
+
 # install headers
 
 IF(APPLE)
@@ -107,7 +117,7 @@ ENDIF(WIN32)
 #############################################################
 # qgis_native library
 
-ADD_LIBRARY(qgis_native SHARED ${QGIS_NATIVE_SRCS} ${QGIS_NATIVE_HDRS})
+ADD_LIBRARY(qgis_native SHARED ${QGIS_NATIVE_SRCS} ${QGIS_NATIVE_MOC_SRCS} ${QGIS_NATIVE_HDRS} ${QGIS_NATIVE_MOC_HDRS})
 SET_PROPERTY(TARGET qgis_native PROPERTY POSITION_INDEPENDENT_CODE ON)
 
 GENERATE_EXPORT_HEADER(

src/native/qgsnative.h

@@ -22,6 +22,7 @@
 #include <QImage>
 #include <QVariant>
 #include <vector>
+#include <QObject>
 
 class QString;
 class QWindow;
@@ -33,8 +34,10 @@ class QWindow;
  * are implemented in subclasses to provide platform abstraction.
  * \since QGIS 3.0
  */
-class NATIVE_EXPORT QgsNative
+class NATIVE_EXPORT QgsNative : public QObject
 {
+    Q_OBJECT
+
   public:
 
     //! Native interface capabilities
@@ -215,6 +218,21 @@ class NATIVE_EXPORT QgsNative
      * \since QGIS 3.4
      */
     virtual void onRecentProjectsChanged( const std::vector< RecentProjectProperties > &recentProjects );
+
+  signals:
+
+    /**
+     * Emitted whenever a USB storage device has been inserted or removed.
+     *
+     * The \a path argument gives the file path to the device (if available).
+     *
+     * If \a inserted is true then the device was inserted. If \a inserted is false then
+     * the device was removed.
+     *
+     * \since QGIS 3.4
+     */
+    void usbStorageNotification( const QString &path, bool inserted );
+
 };
 
 Q_DECLARE_OPERATORS_FOR_FLAGS( QgsNative::Capabilities )

src/native/win/qgswinnative.cpp

@@ -21,12 +21,14 @@
 #include <QString>
 #include <QDir>
 #include <QWindow>
+#include <QAbstractEventDispatcher>
 #include <QtWinExtras/QWinTaskbarButton>
 #include <QtWinExtras/QWinTaskbarProgress>
 #include <QtWinExtras/QWinJumpList>
 #include <QtWinExtras/QWinJumpListItem>
 #include <QtWinExtras/QWinJumpListCategory>
 #include "wintoastlib.h"
+#include <Dbt.h>
 
 QgsNative::Capabilities QgsWinNative::capabilities() const
 {
@@ -57,6 +59,10 @@ void QgsWinNative::initializeMainWindow( QWindow *window,
     mWinToastInitialized = true;
     mCapabilities = mCapabilities | NativeDesktopNotifications;
   }
+
+  mNativeEventFilter = new QgsWinNativeEventFilter();
+  QAbstractEventDispatcher::instance()->installNativeEventFilter( mNativeEventFilter );
+  connect( mNativeEventFilter, &QgsWinNativeEventFilter::usbStorageNotification, this, &QgsNative::usbStorageNotification );
 }
 
 void QgsWinNative::cleanup()
@@ -156,3 +162,27 @@ QgsNative::NotificationResult QgsWinNative::showDesktopNotification( const QStri
 
   return result;
 }
+
+bool QgsWinNativeEventFilter::nativeEventFilter( const QByteArray &, void *message, long * )
+{
+  MSG *pWindowsMessage = static_cast<MSG *>( message );
+  unsigned int wParam = pWindowsMessage->wParam;
+  if ( wParam == DBT_DEVICEARRIVAL || wParam == DBT_DEVICEREMOVECOMPLETE )
+  {
+    long lParam = pWindowsMessage->lParam;
+    unsigned long deviceType = reinterpret_cast<DEV_BROADCAST_HDR *>( lParam )->dbch_devicetype;
+    if ( deviceType == DBT_DEVTYP_VOLUME )
+    {
+      unsigned long unitmask = reinterpret_cast<DEV_BROADCAST_VOLUME *>( lParam )->dbcv_unitmask;
+      for ( int i = 0; i < 32; ++i )
+      {
+        if ( ( unitmask & ( 1 << i ) ) != 0 )
+        {
+          const QChar drive( 65 + i );
+          emit usbStorageNotification( QStringLiteral( "%1:/" ).arg( drive ), wParam == DBT_DEVICEARRIVAL );
+        }
+      }
+    }
+  }
+  return false;
+}

src/native/win/qgswinnative.h

@@ -19,14 +19,30 @@
 #define QGSMACNATIVE_H
 
 #include "qgsnative.h"
-#include <windows.h>
-#include <shlobj.h>
+#include <QAbstractNativeEventFilter>
+
+#include <Windows.h>
+#include <ShlObj.h>
 #pragma comment(lib,"Shell32.lib")
 
 class QWinTaskbarButton;
 class QWinTaskbarProgress;
 class QWindow;
 
+
+class QgsWinNativeEventFilter : public QObject, public QAbstractNativeEventFilter
+{
+    Q_OBJECT
+  public:
+
+    bool nativeEventFilter( const QByteArray &eventType, void *message, long * ) override;
+
+  signals:
+
+    void usbStorageNotification( const QString &path, bool inserted );
+};
+
+
 class NATIVE_EXPORT QgsWinNative : public QgsNative
 {
   public:
@@ -49,6 +65,8 @@ class NATIVE_EXPORT QgsWinNative : public QgsNative
     bool mWinToastInitialized = false;
     QWinTaskbarButton *mTaskButton = nullptr;
     QWinTaskbarProgress *mTaskProgress = nullptr;
+    QgsWinNativeEventFilter *mNativeEventFilter = nullptr;
+
 };
 
 #endif // QGSMACNATIVE_H