Initial drag and drop support.

src/x11_window.c

@@ -306,6 +306,14 @@ static GLboolean createWindow(_GLFWwindow* window,
         XISelectEvents(_glfw.x11.display, window->x11.handle, &eventmask, 1);
     }
 
+    // Enable Xdnd
+    if(_glfw.x11.XdndAware!=None)
+    {
+    	//Announce XDND support
+		Atom version=5;
+		XChangeProperty(_glfw.x11.display, window->x11.handle, _glfw.x11.XdndAware, XA_ATOM, 32, PropModeReplace, (unsigned char*)&version, 1);
+    }
+
     _glfwPlatformSetWindowTitle(window, wndconfig->title);
 
     XRRSelectInput(_glfw.x11.display, window->x11.handle,
@@ -494,6 +502,7 @@ static void leaveFullscreenMode(_GLFWwindow* window)
     }
 }
 
+
 // Process the specified X event
 //
 static void processEvent(XEvent *event)
@@ -703,10 +712,128 @@ static void processEvent(XEvent *event)
                            False,
                            SubstructureNotifyMask | SubstructureRedirectMask,
                            event);
+
+            }
+            else if(event->xclient.message_type == _glfw.x11.XdndEnter)
+            {
+            	// Xdnd Enter: the drag&drop event has started in the window,
+            	// we could be getting the type and possible conversions here
+            	// but since we use always string conversion we don't need
+            	// it
+            }
+            else if(event->xclient.message_type == _glfw.x11.XdndDrop)
+            {
+            	// Xdnd Drop: The drag&drop event has finished dropping on
+            	// the window, ask to convert the selection
+            	_glfw.x11.xdnd.sourceWindow = event->xclient.data.l[0];
+				XConvertSelection(_glfw.x11.display,
+								  _glfw.x11.XdndSelection,
+								  _glfw.x11.UTF8_STRING,
+								  _glfw.x11.XdndSelection,
+								  window->x11.handle, CurrentTime);
+
+            }
+            else if(event->xclient.message_type == _glfw.x11.XdndLeave)
+            {
+
+            }
+            else if(event->xclient.message_type == _glfw.x11.XdndPosition)
+            {
+            	// Xdnd Position: get coordinates of the mouse inside the window
+            	// and update the mouse position
+            	int absX = (event->xclient.data.l[2]>>16) & 0xFFFF;
+            	int absY = (event->xclient.data.l[2]) & 0xFFFF;
+            	int x;
+            	int y;
+
+            	_glfwPlatformGetWindowPos(window,&x,&y);
+
+            	_glfwInputCursorMotion(window,absX-x,absY-y);
+
+				// Xdnd: reply with an XDND status message
+				XClientMessageEvent m;
+				memset(&m, sizeof(m), 0);
+				m.type = ClientMessage;
+				m.display = event->xclient.display;
+				m.window = event->xclient.data.l[0];
+				m.message_type = _glfw.x11.XdndStatus;
+				m.format=32;
+				m.data.l[0] = window->x11.handle;
+				m.data.l[1] = 1; // Always accept the dnd with no rectangle
+				m.data.l[2] = 0; // Specify an empty rectangle
+				m.data.l[3] = 0;
+				m.data.l[4] = _glfw.x11.XdndActionCopy; // We only accept copying
+
+				XSendEvent(_glfw.x11.display, event->xclient.data.l[0], False, NoEventMask, (XEvent*)&m);
+				XFlush(_glfw.x11.display);
             }
 
             break;
         }
+        case SelectionNotify:
+		{
+			if(event->xselection.property != None)
+			{
+				// Xdnd: got a selection notification from the conversion
+				// we asked for, get the data and finish the d&d event
+				char* data;
+				free(_glfw.x11.xdnd.string);
+				_glfw.x11.xdnd.string = NULL;
+				int result = _glfwGetWindowProperty(event->xselection.requestor,
+				                                   event->xselection.property,
+				                                   event->xselection.target,
+				                                   (unsigned char**) &data);
+
+				if(result){
+					// nautilus seems to add a \r at the end of the paths
+					// remove it so paths can be directly used
+					_glfw.x11.xdnd.string = malloc(strlen(data));
+					char *to = _glfw.x11.xdnd.string;
+					const char *from = data;
+					const char *current = strchr(from, '\r');
+					while(current)
+					{
+						int charsToCopy = current - from;
+						memcpy(to, from, (size_t)charsToCopy);
+						to += charsToCopy;
+
+						from = current+1;
+						current = strchr(from, '\r');
+					}
+
+					size_t remaining = strlen(from);
+
+					memcpy(to, from, remaining);
+					to += remaining;
+					*to = 0;
+				}
+
+				XClientMessageEvent m;
+				memset(&m, sizeof(m), 0);
+				m.type = ClientMessage;
+				m.display = _glfw.x11.display;
+				m.window = _glfw.x11.xdnd.sourceWindow;
+				m.message_type = _glfw.x11.XdndFinished;
+				m.format=32;
+				m.data.l[0] = window->x11.handle;
+				m.data.l[1] = result;
+				m.data.l[2] = _glfw.x11.XdndActionCopy; //We only ever copy.
+
+				// Reply that all is well.
+				XSendEvent(_glfw.x11.display, _glfw.x11.xdnd.sourceWindow, False, NoEventMask, (XEvent*)&m);
+
+				XSync(_glfw.x11.display, False);
+
+				XFree(data);
+
+				if(result)
+				{
+					_glfwInputDrop(window,_glfw.x11.xdnd.string);
+
+				}
+			}
+			break;
+		}
 
         case MapNotify:
         {
@@ -897,7 +1024,7 @@ unsigned long _glfwGetWindowProperty(Window window,
                        &bytesAfter,
                        value);
 
-    if (actualType != type)
+    if (type != AnyPropertyType && actualType != type)
         return 0;
 
     return itemCount;
@@ -1001,7 +1128,6 @@ void _glfwPlatformGetWindowPos(_GLFWwindow* window, int* xpos, int* ypos)
     if (child)
     {
         int left, top;
-
         XTranslateCoordinates(_glfw.x11.display, window->x11.handle, child,
                               0, 0, &left, &top, &child);