Implement an NX interface to block flush message queues in multi-user mode. This is necessary to prevent stale window handles when a window is closed

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@4745 42af7a65-404d-4744-a932-0658087f49c3

6 files changed, 187 insertions, 78 deletions

diff --git a/NxWidgets/libnxwidgets/include/ccallback.hxx b/NxWidgets/libnxwidgets/include/ccallback.hxx
index 0e0d5de8b..ca3313a9b 100644
--- a/NxWidgets/libnxwidgets/include/ccallback.hxx
+++ b/NxWidgets/libnxwidgets/include/ccallback.hxx
@@ -99,16 +99,16 @@ namespace NXWidgets
      * either be the context of the owning thread or, in the case of multi-
      * user NX, the context of the NX event listener thread.
      *
-     * @param hWindow Handle to a specific NX window.
-     * @param pRect The rectangle that needs to be re-drawn (in window
+     * @param hwnd Handle to a specific NX window.
+     * @param rect The rectangle that needs to be re-drawn (in window
      * relative coordinates).
      * @param bMore true: More re-draw requests will follow.
-     * @param pvArg User provided argument (see nx_openwindow, nx_requestbg,
+     * @param arg User provided argument (see nx_openwindow, nx_requestbg,
      * nxtk_openwindow, or nxtk_opentoolbar).
      */
      
-    static void redraw(NXHANDLE hWindow, FAR const struct nxgl_rect_s *pRect,
-                       bool bMore, FAR void *pvArg);
+    static void redraw(NXHANDLE hwnd, FAR const struct nxgl_rect_s *rect,
+                       bool bMore, FAR void *arg);
 
     /**
      * Position Callback.  The new positional data is handled by
@@ -118,19 +118,19 @@ namespace NXWidgets
      * either be the context of the owning thread or, in the case of multi-
      * user NX, the context of the NX event listener thread.
      *
-     * @param hWindow Handle to a specific NX window.
-     * @param pSize The size of the window.
-     * @param pPos The position of the upper left hand corner of the window on
+     * @param hwnd Handle to a specific NX window.
+     * @param size The size of the window.
+     * @param pos The position of the upper left hand corner of the window on
      * the overall display.
-     * @param pBounds The bounding rectangle that describes the entire display.
-     * @param pvArg User provided argument (see nx_openwindow, nx_requestbg,
+     * @param bounds The bounding rectangle that describes the entire display.
+     * @param arg User provided argument (see nx_openwindow, nx_requestbg,
      * nxtk_openwindow, or nxtk_opentoolbar).
      */
 
-    static void position(NXHANDLE hWindow, FAR const struct nxgl_size_s *pSize,
-                         FAR const struct nxgl_point_s *pPos,
-                         FAR const struct nxgl_rect_s *pBounds,
-                         FAR void *pvArg);
+    static void position(NXHANDLE hwnd, FAR const struct nxgl_size_s *size,
+                         FAR const struct nxgl_point_s *pos,
+                         FAR const struct nxgl_rect_s *bounds,
+                         FAR void *arg);
 
     /**
      * New mouse data is available for the window.  The new mouse
@@ -144,16 +144,17 @@ namespace NXWidgets
      * The GUI thread is probably sleeping a semaphore, waiting to be
      * awakened by a mouse or keyboard event.
      *
-     * @param hWindow Handle to a specific NX window.
-     * @param pPos The (x,y) position of the mouse.
+     * @param hwnd Handle to a specific NX window.
+     * @param pos The (x,y) position of the mouse.
      * @param buttons See NX_MOUSE_* definitions.
-     * @param pvArg User provided argument (see nx_openwindow, nx_requestbg,
+     * @param arg User provided argument (see nx_openwindow, nx_requestbg,
      * nxtk_openwindow, or nxtk_opentoolbar).
      */
      
 #ifdef CONFIG_NX_MOUSE
-    static void newMouseEvent(NXHANDLE hWindow, FAR const struct nxgl_point_s *pPos,
-                              uint8_t buttons, FAR void *pvArg);
+    static void newMouseEvent(NXHANDLE hwnd,
+                              FAR const struct nxgl_point_s *pos,
+                              uint8_t buttons, FAR void *arg);
 #endif /* CONFIG_NX_MOUSE */
 
     /**
@@ -168,27 +169,49 @@ namespace NXWidgets
      * The GUI thread is probably sleeping a semaphore, waiting to be
      * awakened by a mouse or keyboard event.
      *
-     * @param hWindow Handle to a specific NX window.
-     * @param nCh The number of characters that are available in pStr[].
-     * @param pStr The array of characters.
-     * @param pvArg User provided argument (see nx_openwindow, nx_requestbg,
+     * @param hwnd Handle to a specific NX window.
+     * @param nCh The number of characters that are available in str[].
+     * @param str The array of characters.
+     * @param arg User provided argument (see nx_openwindow, nx_requestbg,
      * nxtk_openwindow, or nxtk_opentoolbar).
      */
 
 #ifdef CONFIG_NX_KBD
-    static void newKeyboardEvent(NXHANDLE hWindow, uint8_t nCh, FAR const uint8_t *pStr,
-                                 FAR void *pvArg);
+    static void newKeyboardEvent(NXHANDLE hwnd, uint8_t nCh,
+                                 FAR const uint8_t *str, FAR void *arg);
 #endif // CONFIG_NX_KBD
 
+    /**
+     * This callback is the response from nx_block (or nxtk_block). Those
+     * blocking interfaces are used to assure that no further messages are
+     * directed to the window. Receipt of the blocked callback signifies
+     * that (1) there are no further pending callbacks and (2) that the
+     * window is now 'defunct' and will receive no further callbacks.
+     *
+     * This callback supports coordinated destruction of a window in multi-
+     * user mode.  In multi-use mode, the client window logic must stay
+     * intact until all of the queued callbacks are processed.  Then the
+     * window may be safely closed.  Closing the window prior with pending
+     * callbacks can lead to bad behavior when the callback is executed.
+     *
+     * @param hwnd. Window handle of the blocked window
+     * @param arg. User provided argument (see nx_openwindow, nx_requestbkgd,
+     *   nxtk_openwindow, or nxtk_opentoolbar)
+     */
+
+#ifdef CONFIG_NX_MULTIUSER
+  static void windowBlocked(NXWINDOW hwnd, FAR void *arg);
+#endif
+
   public:
 
     /**
      * Constructor.
      *
-     * @param pWidgetControl Control object associated with this window
+     * @param widgetControl Control object associated with this window
      */
 
-    CCallback(CWidgetControl *pWidgetControl);
+    CCallback(CWidgetControl *widgetControl);
 
     /**
      * Destructor.
diff --git a/NxWidgets/libnxwidgets/include/cwidgetcontrol.hxx b/NxWidgets/libnxwidgets/include/cwidgetcontrol.hxx
index 757dc1c5b..453cc1115 100644
--- a/NxWidgets/libnxwidgets/include/cwidgetcontrol.hxx
+++ b/NxWidgets/libnxwidgets/include/cwidgetcontrol.hxx
@@ -597,6 +597,31 @@ namespace NXWidgets
 #endif
 
    /**
+    * This event is the response from nx_block (or nxtk_block). Those
+    * blocking interfaces are used to assure that no further messages are
+    * directed to the window. Receipt of the blocked callback signifies
+    * that (1) there are no further pending events and (2) that the
+    * window is now 'defunct' and will receive no further events.
+    *
+    * This event supports coordinated destruction of a window in multi-
+    * user mode.  In multi-use mode, the client window logic must stay
+    * intact until all of the queued callbacks are processed.  Then the
+    * window may be safely closed.  Closing the window prior with pending
+    * callbacks can lead to bad behavior when the callback is executed.
+    *
+    * @param hwnd. Window handle of the blocked window
+    * @param arg. User provided argument (see nx_openwindow, nx_requestbkgd,
+    *   nxtk_openwindow, or nxtk_opentoolbar)
+    */
+
+#ifdef CONFIG_NX_MULTIUSER
+   inline void windowBlocked(void)
+   {
+     m_eventHandlers.raiseBlockedEvent();
+   }
+#endif
+
+   /**
     * This event means that cursor control data is available for the window.
     *
     * @param cursorControl The cursor control code received.
diff --git a/NxWidgets/libnxwidgets/include/cwindoweventhandler.hxx b/NxWidgets/libnxwidgets/include/cwindoweventhandler.hxx
index 1cea0ba68..c414abadb 100644
--- a/NxWidgets/libnxwidgets/include/cwindoweventhandler.hxx
+++ b/NxWidgets/libnxwidgets/include/cwindoweventhandler.hxx
@@ -105,6 +105,12 @@ namespace NXWidgets
 #ifdef CONFIG_NX_KBD
     virtual void handleKeyboardEvent(void) { }
 #endif
+
+    /**
+     * Handle a NX window blocked event
+     */
+ 
+    virtual void handleBlockedEvent(void) { }
   };
 }
 
diff --git a/NxWidgets/libnxwidgets/include/cwindoweventhandlerlist.hxx b/NxWidgets/libnxwidgets/include/cwindoweventhandlerlist.hxx
index 582805691..d9e17de09 100644
--- a/NxWidgets/libnxwidgets/include/cwindoweventhandlerlist.hxx
+++ b/NxWidgets/libnxwidgets/include/cwindoweventhandlerlist.hxx
@@ -160,6 +160,12 @@ namespace NXWidgets
 #ifdef CONFIG_NX_KBD
     void raiseKeyboardEvent(void);
 #endif
+
+    /**
+     * Raise an NX window blocked event.
+     */
+
+    void raiseBlockedEvent(void);
   };
 }
 
diff --git a/NxWidgets/libnxwidgets/src/ccallback.cxx b/NxWidgets/libnxwidgets/src/ccallback.cxx
index 25cb228b3..09dc53a5a 100644
--- a/NxWidgets/libnxwidgets/src/ccallback.cxx
+++ b/NxWidgets/libnxwidgets/src/ccallback.cxx
@@ -60,108 +60,113 @@ using namespace NXWidgets;
  /**
   * Constructor.
   *
-  * @param pWidgetControl Control object associated with this window
+  * @param widgetControl Control object associated with this window
   */
 
-CCallback::CCallback(CWidgetControl *pWidgetControl)
+CCallback::CCallback(CWidgetControl *widgetControl)
 {
   // Initialize the callback vtable
 
   m_callbacks.redraw   = redraw;
   m_callbacks.position = position;
+#ifdef CONFIG_NX_MOUSE
   m_callbacks.mousein  = newMouseEvent;
+#endif
+#ifdef CONFIG_NX_KBD
   m_callbacks.kbdin    = newKeyboardEvent;
+#endif
+  m_callbacks.blocked  = windowBlocked;
 }
 
  /**
   * ReDraw Callback.  The redraw action is handled by CWidgetControl:redrawEvent.
   *
-  * @param hWindow Handle to a specific NX window.
-  * @param pRect The rectangle that needs to be re-drawn (in window
+  * @param hwnd Handle to a specific NX window.
+  * @param rect The rectangle that needs to be re-drawn (in window
   * relative coordinates).
   * @param bMore true: More re-draw requests will follow.
-  * @param pvArg User provided argument (see nx_openwindow, nx_requestbg,
+  * @param arg User provided argument (see nx_openwindow, nx_requestbg,
   * nxtk_openwindow, or nxtk_opentoolbar).
   */
      
-void CCallback::redraw(NXHANDLE hWindow,
-                       FAR const struct nxgl_rect_s *pRect,
-                       bool bMore, FAR void *pvArg)
+void CCallback::redraw(NXHANDLE hwnd,
+                       FAR const struct nxgl_rect_s *rect,
+                       bool bMore, FAR void *arg)
 {
-  gvdbg("hWindow=%p pRect={(%d,%d),(%d,%d)} bMore=%s\n",
-         hWindow,
-         pRect->pt1.x, pRect->pt1.y, pRect->pt2.x, pRect->pt2.y,
+  gvdbg("hwnd=%p rect={(%d,%d),(%d,%d)} bMore=%s\n",
+         hwnd,
+         rect->pt1.x, rect->pt1.y, rect->pt2.x, rect->pt2.y,
          bMore ? "true" : "false");
 
   // The argument must be the CWidgetControl instance
 
-  CWidgetControl *This = (CWidgetControl *)pvArg;
+  CWidgetControl *This = (CWidgetControl *)arg;
 
   // Just forward the callback to the CWidgetControl::redrawEvent method
 
-  This->redrawEvent(pRect, bMore);
+  This->redrawEvent(rect, bMore);
 }
 
  /**
   * Position Callback. The new positional data is handled by
   * CWidgetControl::geometryEvent.
   *
-  * @param hWindow Handle to a specific NX window.
-  * @param pSize The size of the window.
-  * @param pPos The position of the upper left hand corner of the window on
+  * @param hwnd Handle to a specific NX window.
+  * @param size The size of the window.
+  * @param pos The position of the upper left hand corner of the window on
   * the overall display.
-  * @param pBounds The bounding rectangle that describes the entire display.
-  * @param pvArg User provided argument (see nx_openwindow, nx_requestbg,
+  * @param bounds The bounding rectangle that describes the entire display.
+  * @param arg User provided argument (see nx_openwindow, nx_requestbg,
   * nxtk_openwindow, or nxtk_opentoolbar).
   */
 
-void CCallback::position(NXHANDLE hWindow,
-                         FAR const struct nxgl_size_s *pSize,
-                         FAR const struct nxgl_point_s *pPos,
-                         FAR const struct nxgl_rect_s *pBounds,
-                         FAR void *pvArg)
+void CCallback::position(NXHANDLE hwnd,
+                         FAR const struct nxgl_size_s *size,
+                         FAR const struct nxgl_point_s *pos,
+                         FAR const struct nxgl_rect_s *bounds,
+                         FAR void *arg)
 {
-  gvdbg("hWindow=%p pSize=(%d,%d) pPos=(%d,%d) pBounds={(%d,%d),(%d,%d)} pvArg=%p\n",
-        hWindow, pSize->w, pSize->h, pPos->x, pPos->y,
-        pBounds->pt1.x, pBounds->pt1.y, pBounds->pt2.x, pBounds->pt2.y,
-        pvArg);
+  gvdbg("hwnd=%p size=(%d,%d) pos=(%d,%d) bounds={(%d,%d),(%d,%d)} arg=%p\n",
+        hwnd, size->w, size->h, pos->x, pos->y,
+        bounds->pt1.x, bounds->pt1.y, bounds->pt2.x, bounds->pt2.y,
+        arg);
 
 
   // The argument must be the CWidgetControl instance
 
-  CWidgetControl *This = (CWidgetControl *)pvArg;
+  CWidgetControl *This = (CWidgetControl *)arg;
 
   // Just forward the callback to the CWidgetControl::geometry method
 
-  This->geometryEvent(hWindow, pSize, pPos, pBounds);
+  This->geometryEvent(hwnd, size, pos, bounds);
 }
 
  /**
   * New mouse data is available for the window.  The new mouse data is
   * handled by CWidgetControl::newMouseEvent.
   *
-  * @param hWindow Handle to a specific NX window.
-  * @param pPos The (x,y) position of the mouse.
+  * @param hwnd Handle to a specific NX window.
+  * @param pos The (x,y) position of the mouse.
   * @param buttons See NX_MOUSE_* definitions.
-  * @param pvArg User provided argument (see nx_openwindow, nx_requestbg,
+  * @param arg User provided argument (see nx_openwindow, nx_requestbg,
   * nxtk_openwindow, or nxtk_opentoolbar).
   */
-     
+
 #ifdef CONFIG_NX_MOUSE
-void CCallback::newMouseEvent(NXHANDLE hWindow,
-                              FAR const struct nxgl_point_s *pPos,
-                              uint8_t buttons, FAR void *pvArg)
+void CCallback::newMouseEvent(NXHANDLE hwnd,
+                              FAR const struct nxgl_point_s *pos,
+                              uint8_t buttons, FAR void *arg)
 {
-  gvdbg("hWindow=%p pPos=(%d,%d) buttons=%02x pvArg=%p\n", 
-        hWindow, pPos->x, pPos->y, buttons, pvArg);
+  gvdbg("hwnd=%p pos=(%d,%d) buttons=%02x arg=%p\n", 
+        hwnd, pos->x, pos->y, buttons, arg);
 
   // The argument must be the CWidgetControl instance
 
-  CWidgetControl *This = (CWidgetControl *)pvArg;
+  CWidgetControl *This = (CWidgetControl *)arg;
 
   // Just forward the callback to the CWidgetControl::newMouseEvent method
 
-  This->newMouseEvent(pPos, buttons);
+  This->newMouseEvent(pos, buttons);
 }
 #endif /* CONFIG_NX_MOUSE */
 
@@ -169,27 +174,60 @@ void CCallback::newMouseEvent(NXHANDLE hWindow,
  * New keyboard/keypad data is available for the window.  The new keyboard
  * data is handled by CWidgetControl::newKeyboardEvent.
  *
- * @param hWindow Handle to a specific NX window.
- * @param nCh The number of characters that are available in pStr[].
- * @param pStr The array of characters.
- * @param pvArg User provided argument (see nx_openwindow, nx_requestbg,
+ * @param hwnd Handle to a specific NX window.
+ * @param nCh The number of characters that are available in str[].
+ * @param str The array of characters.
+ * @param arg User provided argument (see nx_openwindow, nx_requestbg,
  * nxtk_openwindow, or nxtk_opentoolbar).
  */
 
 #ifdef CONFIG_NX_KBD
-void CCallback::newKeyboardEvent(NXHANDLE hWindow, uint8_t nCh,
-                                 FAR const uint8_t *pStr,
-                                 FAR void *pvArg)
+void CCallback::newKeyboardEvent(NXHANDLE hwnd, uint8_t nCh,
+                                 FAR const uint8_t *str,
+                                 FAR void *arg)
 {
-  gvdbg("hWindow=%p nCh=%d pvArg=%p\n",
-        hWindow, nCh, pvArg);
+  gvdbg("hwnd=%p nCh=%d arg=%p\n", hwnd, nCh, arg);
 
   // The argument must be the CWidgetControl instance
 
-  CWidgetControl *This = (CWidgetControl *)pvArg;
+  CWidgetControl *This = (CWidgetControl *)arg;
 
   // Just forward the callback to the CWidgetControl::newKeyboardEvent method
 
-  This->newKeyboardEvent(nCh, pStr);
+  This->newKeyboardEvent(nCh, str);
+}
+
+/**
+ * This callback is the response from nx_block (or nxtk_block). Those
+ * blocking interfaces are used to assure that no further messages are
+ * directed to the window. Receipt of the blocked callback signifies
+ * that (1) there are no further pending callbacks and (2) that the
+ * window is now 'defunct' and will receive no further callbacks.
+ *
+ * This callback supports coordinated destruction of a window in multi-
+ * user mode.  In multi-use more, the client window logic must stay
+ * intact until all of the queued callbacks are processed.  Then the
+ * window may be safely closed.  Closing the window prior with pending
+ * callbacks can lead to bad behavior when the callback is executed.
+ *
+ * @param hwnd. Window handle of the blocked window
+ * @param arg. User provided argument (see nx_openwindow, nx_requestbkgd,
+ *   nxtk_openwindow, or nxtk_opentoolbar)
+ */
+
+#ifdef CONFIG_NX_MULTIUSER
+void CCallback::windowBlocked(NXWINDOW hwnd, FAR void *arg)
+{
+  gvdbg("hwnd=%p arg=%p\n", hwnd, arg);
+
+  // The argument must be the CWidgetControl instance
+
+  CWidgetControl *This = (CWidgetControl *)arg;
+
+  // Just forward the callback to the CWidgetControl::windowBlocked method
+
+  This->windowBlocked();
 }
+#endif
+
 #endif // CONFIG_NX_KBD
diff --git a/NxWidgets/libnxwidgets/src/cwindoweventhandlerlist.cxx b/NxWidgets/libnxwidgets/src/cwindoweventhandlerlist.cxx
index 5f3048b63..15b2c65ff 100644
--- a/NxWidgets/libnxwidgets/src/cwindoweventhandlerlist.cxx
+++ b/NxWidgets/libnxwidgets/src/cwindoweventhandlerlist.cxx
@@ -160,3 +160,14 @@ void CWindowEventHandlerList::raiseKeyboardEvent(void)
 #endif
 }
 
+/**
+ * Raise an NX window blocked event.
+ */
+
+void CWindowEventHandlerList::raiseBlockedEvent(void)
+{
+  for (int i = 0; i < m_eventHandlers.size(); ++i)
+    {
+      m_eventHandlers.at(i)->handleBlockedEvent();
+    }
+}