[typing-break] Reset timer after suspend

This patch does 2 things:
1) Defines a DrwTimer that we use instead of GTimer. This is just a thin
wrapper around g_get_current_time, and it means we can accurately track
typing/idle periods based on real-world wall-clock time, which GTimer is
apparently not intended to do.

2) The typing monitor has some complicated state handling where it transitions
between an IDLE state and a TYPING state. This transition is based on running a
callback once per second, and checking whether any keystrokes have been
recorded since the last time the callback was called. The actual idle *time* is
tracked separately, independently of these two states, but only when we are in
the IDLE *state* was the idle *time* checked to see if we should reset the
break timer. This leads to a race condition -- if we suspend while in the
TYPING state, then eventually we will wake up, notice that no key press has
happened in the last second, *reset the idle timer*, transition to the IDLE
state, and then check the amount of time on the idle timer. We will thus never
notice the amount of time that the computer was suspended.

I considered making the IDLE/TYPING transition code smarter, but it turns out
the desired behavior for the two states is entirely identical anyway, so rather
than adding more complexity to this pointless code, I just diked it out and
replaced them both by a single state called RUNNING.

Closes bug #430797.

5 files changed, 134 insertions, 74 deletions

diff --git a/typing-break/Makefile.am b/typing-break/Makefile.am
index 31b090782..f1b89bf65 100644
--- a/typing-break/Makefile.am
+++ b/typing-break/Makefile.am
@@ -11,7 +11,9 @@ gnome_typing_monitor_SOURCES =			\
 	drw-utils.c				\
 	drw-utils.h				\
 	drw-selection.c				\
-	drw-selection.h
+	drw-selection.h				\
+	drw-timer.c				\
+	drw-timer.h
 
 gnome_typing_monitor_CPPFLAGS = \
 	-DGNOMELOCALEDIR="\"$(datadir)/locale\""	\
diff --git a/typing-break/drw-break-window.c b/typing-break/drw-break-window.c
index 813c5b941..8edf8e04a 100644
--- a/typing-break/drw-break-window.c
+++ b/typing-break/drw-break-window.c
@@ -35,6 +35,7 @@
 #include "drwright.h"
 #include "drw-utils.h"
 #include "drw-break-window.h"
+#include "drw-timer.h"
 
 struct _DrwBreakWindowPrivate {
 	GtkWidget *clock_label;
@@ -44,7 +45,7 @@ struct _DrwBreakWindowPrivate {
 	GtkWidget *postpone_entry;
 	GtkWidget *postpone_button;
 
-	GTimer    *timer;
+	DrwTimer  *timer;
 
 	gint       break_time;
 	gchar     *break_text;
@@ -270,7 +271,7 @@ drw_break_window_init (DrwBreakWindow *window)
 
 	gtk_window_stick (GTK_WINDOW (window));
 
-	priv->timer = g_timer_new ();
+	priv->timer = drw_timer_new ();
 
 	/* Make sure we have a valid time label from the start. */
 	clock_timeout_cb (window);
@@ -319,7 +320,7 @@ drw_break_window_dispose (GObject *object)
 	priv = window->priv;
 
 	if (priv->timer) {
-		g_timer_destroy (priv->timer);
+		drw_timer_destroy (priv->timer);
 		priv->timer = NULL;
 	}
 
@@ -382,7 +383,7 @@ clock_timeout_cb (DrwBreakWindow *window)
 
 	priv = window->priv;
 
-	seconds = 1 + priv->break_time - g_timer_elapsed (priv->timer, NULL);
+	seconds = 1 + priv->break_time - drw_timer_elapsed (priv->timer);
 	seconds = MAX (0, seconds);
 
 	if (seconds == 0) {
diff --git a/typing-break/drw-timer.c b/typing-break/drw-timer.c
new file mode 100644
index 000000000..d108034c6
--- /dev/null
+++ b/typing-break/drw-timer.c
@@ -0,0 +1,52 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
+/*
+ * Copyright (C) 2009 Nathaniel Smith <njs@pobox.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#include <glib.h>
+#include "drw-timer.h"
+
+struct _DrwTimer 
+{
+	GTimeVal start_time;
+};
+
+DrwTimer * drw_timer_new () 
+{
+	DrwTimer * timer = g_new0 (DrwTimer, 1);
+	drw_timer_start (timer);
+	return timer;
+}
+
+void drw_timer_start (DrwTimer *timer) 
+{
+	g_get_current_time (&timer->start_time);
+}
+
+double drw_timer_elapsed (DrwTimer *timer) 
+{
+	GTimeVal now;
+	g_get_current_time (&now);
+	return now.tv_sec - timer->start_time.tv_sec;
+}
+
+void drw_timer_destroy (DrwTimer *timer)
+{
+	g_free (timer);
+}
+
diff --git a/typing-break/drw-timer.h b/typing-break/drw-timer.h
new file mode 100644
index 000000000..1a259c5c7
--- /dev/null
+++ b/typing-break/drw-timer.h
@@ -0,0 +1,42 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
+/*
+ * Copyright (C) 2009 Nathaniel Smith <njs@pobox.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#ifndef __DRW_TIMER_H__
+#define __DRW_TIMER_H__
+
+/*
+ * This file defines a timer interface similar to GTimer, but defined in real
+ * wall-clock time. A GTimer may stop counting while the computer is suspended
+ * or the process is stopped:
+ *   https://bugzilla.gnome.org/show_bug.cgi?id=552994
+ * but a DrwTimer keeps counting regardless.
+ *
+ * Currently this only provides second resolution as compared to GTimer's
+ * microsecond resolution, but a typing break program doesn't really need
+ * microsecond resolution anyway.
+ */
+
+typedef struct _DrwTimer DrwTimer;
+DrwTimer * drw_timer_new ();
+void drw_timer_start (DrwTimer *timer);
+double drw_timer_elapsed (DrwTimer *timer);
+void drw_timer_destroy (DrwTimer *timer);
+
+#endif /* __DRW_TIMER_H__ */
diff --git a/typing-break/drwright.c b/typing-break/drwright.c
index 3775dbdba..9c7c2a0d3 100644
--- a/typing-break/drwright.c
+++ b/typing-break/drwright.c
@@ -21,7 +21,6 @@
  */
 
 #include <config.h>
-#include <time.h>
 #include <string.h>
 #include <math.h>
 #include <glib/gi18n.h>
@@ -34,6 +33,7 @@
 #include "drw-break-window.h"
 #include "drw-monitor.h"
 #include "drw-utils.h"
+#include "drw-timer.h"
 
 #define BLINK_TIMEOUT        200
 #define BLINK_TIMEOUT_MIN    120
@@ -44,10 +44,8 @@
 
 typedef enum {
 	STATE_START,
-	STATE_IDLE,
-	STATE_TYPE,
-	STATE_WARN_TYPE,
-	STATE_WARN_IDLE,
+	STATE_RUNNING,
+	STATE_WARN,
 	STATE_BREAK_SETUP,
 	STATE_BREAK,
 	STATE_BREAK_DONE_SETUP,
@@ -64,14 +62,12 @@ struct _DrWright {
 	GtkUIManager *ui_manager;
 
 	DrwState        state;
-	GTimer         *timer;
-	GTimer         *idle_timer;
+	DrwTimer       *timer;
+	DrwTimer       *idle_timer;
 
 	gint            last_elapsed_time;
 	gint            save_last_time;
 
-	gboolean        is_active;
-
 	/* Time settings. */
 	gint            type_time;
 	gint            break_time;
@@ -166,7 +162,7 @@ update_icon (DrWright *dr)
 		break;
 
 	default:
-		r = (float) (g_timer_elapsed (dr->timer, NULL) + dr->save_last_time) /
+		r = (float) (drw_timer_elapsed (dr->timer) + dr->save_last_time) /
 		    (float) dr->type_time;
 		break;
 	}
@@ -174,8 +170,7 @@ update_icon (DrWright *dr)
 	offset = CLAMP ((height - 0) * (1.0 - r), 1, height - 0);
 
 	switch (dr->state) {
-	case STATE_WARN_TYPE:
-	case STATE_WARN_IDLE:
+	case STATE_WARN:
 		pixbuf = dr->red_bar;
 		set_pixbuf = FALSE;
 		break;
@@ -220,7 +215,7 @@ blink_timeout_cb (DrWright *dr)
 	gfloat r;
 	gint   timeout;
 
-	r = (dr->type_time - g_timer_elapsed (dr->timer, NULL) - dr->save_last_time) / dr->warn_time;
+	r = (dr->type_time - drw_timer_elapsed (dr->timer) - dr->save_last_time) / dr->warn_time;
 	timeout = BLINK_TIMEOUT + BLINK_TIMEOUT_FACTOR * r;
 
 	if (timeout < BLINK_TIMEOUT_MIN) {
@@ -301,11 +296,11 @@ maybe_change_state (DrWright *dr)
 	gint elapsed_idle_time;
 
 	if (debug) {
-		g_timer_reset (dr->idle_timer);
+		drw_timer_start (dr->idle_timer);
 	}
 
-	elapsed_time = g_timer_elapsed (dr->timer, NULL) + dr->save_last_time;
-	elapsed_idle_time = g_timer_elapsed (dr->idle_timer, NULL);
+	elapsed_time = drw_timer_elapsed (dr->timer) + dr->save_last_time;
+	elapsed_idle_time = drw_timer_elapsed (dr->idle_timer);
 
 	if (elapsed_time > dr->last_elapsed_time + dr->warn_time) {
 		/* If the timeout is delayed by the amount of warning time, then
@@ -327,56 +322,28 @@ maybe_change_state (DrWright *dr)
 
 		dr->save_last_time = 0;
 
-		g_timer_start (dr->timer);
-		g_timer_start (dr->idle_timer);
+		drw_timer_start (dr->timer);
+		drw_timer_start (dr->idle_timer);
 
 		if (dr->enabled) {
-			dr->state = STATE_IDLE;
+			dr->state = STATE_RUNNING;
 		}
 
 		update_tooltip (dr);
 		stop_blinking (dr);
 		break;
 
-	case STATE_IDLE:
+	case STATE_RUNNING:
+	case STATE_WARN:
 		if (elapsed_idle_time >= dr->break_time) {
 			dr->state = STATE_BREAK_DONE_SETUP;
-		} else if (dr->is_active) {
-			dr->state = STATE_TYPE;
-		}
-		break;
-
-	case STATE_TYPE:
-		if (elapsed_time >= dr->type_time - dr->warn_time) {
-			dr->state = STATE_WARN_TYPE;
-
-			start_blinking (dr);
  		} else if (elapsed_time >= dr->type_time) {
 			dr->state = STATE_BREAK_SETUP;
+		} else if (dr->state != STATE_WARN
+			   && elapsed_time >= dr->type_time - dr->warn_time) {
+			dr->state = STATE_WARN;
+			start_blinking (dr);
 		}
-		else if (!dr->is_active) {
-			dr->state = STATE_IDLE;
-			g_timer_start (dr->idle_timer);
-		}
-		break;
-
-	case STATE_WARN_TYPE:
-		if (elapsed_time >= dr->type_time) {
-			dr->state = STATE_BREAK_SETUP;
-		}
-		else if (!dr->is_active) {
-			dr->state = STATE_WARN_IDLE;
-		}
-		break;
-
-	case STATE_WARN_IDLE:
-		if (elapsed_idle_time >= dr->break_time) {
-			dr->state = STATE_BREAK_DONE_SETUP;
-		}
-		else if (dr->is_active) {
-			dr->state = STATE_WARN_TYPE;
-		}
-
 		break;
 
 	case STATE_BREAK_SETUP:
@@ -392,7 +359,7 @@ maybe_change_state (DrWright *dr)
 		gtk_status_icon_set_from_pixbuf (dr->icon,
 						 dr->red_bar);
 
-		g_timer_start (dr->timer);
+		drw_timer_start (dr->timer);
 
 		dr->break_window = drw_break_window_new ();
 
@@ -438,17 +405,14 @@ maybe_change_state (DrWright *dr)
 		break;
 
 	case STATE_BREAK_DONE:
-		if (dr->is_active) {
-			dr->state = STATE_START;
-			if (dr->break_window) {
-				gtk_widget_destroy (dr->break_window);
-				dr->break_window = NULL;
-			}
+		dr->state = STATE_START;
+		if (dr->break_window) {
+			gtk_widget_destroy (dr->break_window);
+			dr->break_window = NULL;
 		}
 		break;
 	}
 
-	dr->is_active = FALSE;
 	dr->last_elapsed_time = elapsed_time;
 
 	update_icon (dr);
@@ -468,7 +432,7 @@ update_tooltip (DrWright *dr)
 		return TRUE;
 	}
 
-	elapsed_time = g_timer_elapsed (dr->timer, NULL);
+	elapsed_time = drw_timer_elapsed (dr->timer);
 
 	min = floor (0.5 + (dr->type_time - elapsed_time - dr->save_last_time) / 60.0);
 
@@ -492,8 +456,7 @@ static void
 activity_detected_cb (DrwMonitor *monitor,
 		      DrWright   *dr)
 {
-	dr->is_active = TRUE;
-	g_timer_start (dr->idle_timer);
+	drw_timer_start (dr->idle_timer);
 }
 
 static void
@@ -634,10 +597,10 @@ break_window_postpone_cb (GtkWidget *window,
 
 	gtk_widget_destroy (dr->break_window);
 
-	dr->state = STATE_TYPE;
+	dr->state = STATE_RUNNING;
 	dr->break_window = NULL;
 
-	elapsed_time = g_timer_elapsed (dr->timer, NULL);
+	elapsed_time = drw_timer_elapsed (dr->timer);
 
 	if (elapsed_time + dr->save_last_time >= dr->type_time) {
 		/* Typing time has expired, but break was postponed.
@@ -648,7 +611,7 @@ break_window_postpone_cb (GtkWidget *window,
 		dr->save_last_time = dr->type_time - MAX (dr->warn_time, (gint) postpone_time);
 	}
 
-	g_timer_start (dr->timer);
+	drw_timer_start (dr->timer);
 	maybe_change_state (dr);
 	update_icon (dr);
 	update_tooltip (dr);
@@ -783,8 +746,8 @@ drwright_new (void)
 	item = gtk_ui_manager_get_widget (dr->ui_manager, "/Pop/TakeABreak");
 	gtk_widget_set_sensitive (item, dr->enabled);
 
-	dr->timer = g_timer_new ();
-	dr->idle_timer = g_timer_new ();
+	dr->timer = drw_timer_new ();
+	dr->idle_timer = drw_timer_new ();
 
 	dr->state = STATE_START;