nitpicker: New signal handling, bg color config

This patch overhauls the signal handling of nitpicker to clear the way
towards dynamic reconfiguration. Furthermore, it moves the
implementation of the global-keys handling and input utilities to
separate files.

os/src/server/nitpicker/README

@@ -65,3 +65,10 @@ the "launchpad -> testnit" program is running. As soon as testnit gets started
 by launchpad, testnit will receive the events. If the order was reversed,
 launchpad would always receive the events.
 
+Background color
+----------------
+
+The background color can be defined via the '<background>' config node:
+
+! <background color="#112233" />
+

os/src/server/nitpicker/genode/global_keys.cc

@@ -0,0 +1,90 @@
+/*
+ * \brief  Global keys handling
+ * \author Norman Feske
+ * \date   2013-09-07
+ */
+
+/*
+ * Copyright (C) 2013 Genode Labs GmbH
+ *
+ * This file is part of the Genode OS framework, which is distributed
+ * under the terms of the GNU General Public License version 2.
+ */
+
+/* Genode includes */
+#include <os/config.h>
+
+/* local includes */
+#include "global_keys.h"
+
+
+Global_keys::Policy *Global_keys::_lookup_policy(char const *key_name)
+{
+	for (unsigned i = 0; i < NUM_POLICIES; i++)
+		if (Genode::strcmp(key_name, Input::key_name((Input::Keycode)i)) == 0)
+			return &_policies[i];
+
+	return 0;
+}
+
+
+void Global_keys::apply_config(Session_list &session_list)
+{
+	for (unsigned i = 0; i < NUM_POLICIES; i++)
+		_policies[i].undefine();
+
+	using Genode::Xml_node;
+	try {
+		Xml_node node = Genode::config()->xml_node().sub_node("global-keys").sub_node("key");
+
+		for (; ; node = node.next("key")) {
+
+			if (!node.has_attribute("name")) {
+				PWRN("attribute 'name' missing in <key> config node");
+				continue;
+			}
+
+			char name[32]; name[0] = 0;
+			node.attribute("name").value(name, sizeof(name));
+
+			Policy * policy = _lookup_policy(name);
+			if (!policy) {
+				PWRN("invalid key name \"%s\"", name);
+				continue;
+			}
+
+			/* if two policies match, give precedence to policy defined first */
+			if (policy->defined())
+				continue;
+
+			if (node.has_attribute("operation")) {
+				Xml_node::Attribute operation = node.attribute("operation");
+
+				if (operation.has_value("kill")) {
+					policy->operation_kill();
+					continue;
+				} else if (operation.has_value("xray")) {
+					policy->operation_xray();
+					continue;
+				} else {
+					char buf[32]; buf[0] = 0;
+					operation.value(buf, sizeof(buf));
+					PWRN("unknown operation \"%s\" for key %s", buf, name);
+				}
+				continue;
+			}
+
+			if (!node.has_attribute("label")) {
+				PWRN("missing 'label' attribute for key %s", name);
+				continue;
+			}
+
+			/* assign policy to matching client session */
+			for (Session *s = session_list.first(); s; s = s->next())
+				if (node.attribute("label").has_value(s->label()))
+					policy->client(s);
+		}
+
+	} catch (Xml_node::Nonexistent_sub_node) { }
+}
+

os/src/server/nitpicker/genode/target.mk

@@ -3,9 +3,13 @@ LIBS     = base blit config
 SRC_CC   = main.cc \
            view_stack.cc \
            view.cc \
-           user_state.cc
+           user_state.cc \
+           global_keys.cc
 SRC_BIN  = default.tff
 
+# enable C++11 support
+CC_CXX_OPT += -std=gnu++11
+
 INC_DIR  = $(PRG_DIR)/../include \
            $(PRG_DIR)/../data
 

os/src/server/nitpicker/include/background.h

@@ -19,6 +19,8 @@
 
 struct Background : private Texture, Session, View
 {
+	Color color;
+
 	/*
 	 * The background uses no texture. Therefore
 	 * we can pass a null pointer as texture argument
@@ -28,7 +30,8 @@ struct Background : private Texture, Session, View
 	:
 		Texture(Area(0, 0)), Session("", *this, 0, BLACK),
 		View(*this, View::NOT_STAY_TOP, View::NOT_TRANSPARENT,
-		     View::BACKGROUND, Rect(Point(0, 0), size))
+		     View::BACKGROUND, Rect(Point(0, 0), size)),
+		color(25, 37, 50)
 	{ }
 
 
@@ -49,7 +52,7 @@ struct Background : private Texture, Session, View
 	void draw(Canvas &canvas, Mode const &mode) const
 	{
 		Clip_guard clip_guard(canvas, *this);
-		canvas.draw_box(*this, Color(25, 37, 50));
+		canvas.draw_box(*this, color);
 	}
 };
 

os/src/server/nitpicker/include/input.h

@@ -0,0 +1,98 @@
+/*
+ * \brief  Input handling utilities
+ * \author Norman Feske
+ * \date   2013-09-07
+ */
+
+/*
+ * Copyright (C) 2013 Genode Labs GmbH
+ *
+ * This file is part of the Genode OS framework, which is distributed
+ * under the terms of the GNU General Public License version 2.
+ */
+
+#ifndef _INPUT_H_
+#define _INPUT_H_
+
+/* Genode includes */
+#include <input/event.h>
+
+/* local includes */
+#include "user_state.h"
+
+
+/**
+ * Determine number of events that can be merged into one
+ *
+ * \param ev   pointer to first event array element to check
+ * \param max  size of the event array
+ * \return     number of events subjected to merge
+ */
+static unsigned num_consecutive_events(Input::Event const *ev, unsigned max)
+{
+	if (max < 1) return 0;
+	if (ev->type() != Input::Event::MOTION) return 1;
+
+	bool first_is_absolute = ev->is_absolute_motion();
+
+	/* iterate until we get a different event type, start at second */
+	unsigned cnt = 1;
+	for (ev++ ; cnt < max; cnt++, ev++) {
+		if (ev->type() != Input::Event::MOTION) break;
+		if (first_is_absolute != ev->is_absolute_motion()) break;
+	}
+	return cnt;
+}
+
+
+/**
+ * Merge consecutive motion events
+ *
+ * \param ev  event array to merge
+ * \param n   number of events to merge
+ * \return    merged motion event
+ */
+static Input::Event merge_motion_events(Input::Event const *ev, unsigned n)
+{
+	Input::Event res;
+	for (unsigned i = 0; i < n; i++, ev++)
+		res = Input::Event(Input::Event::MOTION, 0, ev->ax(), ev->ay(),
+		                   res.rx() + ev->rx(), res.ry() + ev->ry());
+	return res;
+}
+
+
+static void import_input_events(Input::Event *ev_buf, unsigned num_ev,
+                                User_state &user_state)
+{
+	/*
+	 * Take events from input event buffer, merge consecutive motion
+	 * events, and pass result to the user state.
+	 */
+	for (unsigned src_ev_cnt = 0; src_ev_cnt < num_ev; src_ev_cnt++) {
+
+		Input::Event *e = &ev_buf[src_ev_cnt];
+		Input::Event curr = *e;
+
+		if (e->type() == Input::Event::MOTION) {
+			unsigned n = num_consecutive_events(e, num_ev - src_ev_cnt);
+			curr = merge_motion_events(e, n);
+
+			/* skip merged events */
+			src_ev_cnt += n - 1;
+		}
+
+		/*
+		 * If subsequential relative motion events are merged to
+		 * a zero-motion event, drop it. Otherwise, it would be
+		 * misinterpreted as absolute event pointing to (0, 0).
+		 */
+		if (e->is_relative_motion() && curr.rx() == 0 && curr.ry() == 0)
+			continue;
+
+		/* pass event to user state */
+		user_state.handle_event(curr);
+	}
+}
+
+#endif /* _INPUT_H_ */

os/src/server/nitpicker/include/session.h

@@ -17,6 +17,9 @@
 /* Genode includes */
 #include <util/list.h>
 #include <util/string.h>
+#include <nitpicker_gfx/color.h>
+#include <nitpicker_gfx/geometry.h>
+#include <nitpicker_gfx/canvas.h>
 
 class Texture;
 class View;