xf86-input-libinput 0.19.0

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>

.gitignore

@@ -76,3 +76,11 @@ core
 #		Edit the following section as needed
 # For example, !report.pc overrides *.pc. See 'man gitignore'
 # 
+*.log
+*.trs
+*.swp
+*.announce
+*.sig
+test-driver
+tags
+.vimdir

Makefile.am

@@ -21,12 +21,14 @@
 
 DISTCHECK_CONFIGURE_FLAGS = --with-sdkdir='$${includedir}/xorg'
 
-SUBDIRS = src include man
+SUBDIRS = src include man test
 MAINTAINERCLEANFILES = ChangeLog INSTALL
 
 pkgconfigdir = $(libdir)/pkgconfig
 pkgconfig_DATA = xorg-libinput.pc
 
+dist_xorgconf_DATA = conf/60-libinput.conf
+
 .PHONY: ChangeLog INSTALL
 
 INSTALL:
@@ -37,4 +39,4 @@ ChangeLog:
 
 dist-hook: ChangeLog INSTALL
 
-EXTRA_DIST = conf/99-libinput.conf README.md
+EXTRA_DIST = README.md

conf/60-libinput.conf

@@ -0,0 +1,28 @@
+# Match on all types of devices but tablet devices and joysticks
+Section "InputClass"
+        Identifier "libinput pointer catchall"
+        MatchIsPointer "on"
+        MatchDevicePath "/dev/input/event*"
+        Driver "libinput"
+EndSection
+
+Section "InputClass"
+        Identifier "libinput keyboard catchall"
+        MatchIsKeyboard "on"
+        MatchDevicePath "/dev/input/event*"
+        Driver "libinput"
+EndSection
+
+Section "InputClass"
+        Identifier "libinput touchpad catchall"
+        MatchIsTouchpad "on"
+        MatchDevicePath "/dev/input/event*"
+        Driver "libinput"
+EndSection
+
+Section "InputClass"
+        Identifier "libinput touchscreen catchall"
+        MatchIsTouchscreen "on"
+        MatchDevicePath "/dev/input/event*"
+        Driver "libinput"
+EndSection

conf/99-libinput.conf

@@ -1,6 +0,0 @@
-# Use the libinput driver for all event devices
-Section "InputClass"
-	Identifier "libinput"
-	Driver "libinput"
-	MatchDevicePath "/dev/input/event*"
-EndSection

configure.ac

@@ -23,7 +23,7 @@
 # Initialize Autoconf
 AC_PREREQ([2.60])
 AC_INIT([xf86-input-libinput],
-        [0.8.0],
+        [0.19.0],
         [https://bugs.freedesktop.org/enter_bug.cgi?product=xorg],
         [xf86-input-libinput])
 AC_CONFIG_SRCDIR([Makefile.am])
@@ -45,7 +45,7 @@ XORG_DEFAULT_OPTIONS
 
 # Obtain compiler/linker options from server and required extensions
 PKG_CHECK_MODULES(XORG, [xorg-server >= 1.10] xproto [inputproto >= 2.2])
-PKG_CHECK_MODULES(LIBINPUT, [libinput >= 0.11.0])
+PKG_CHECK_MODULES(LIBINPUT, [libinput >= 1.1.901])
 
 # Define a configure option for an alternate input module directory
 AC_ARG_WITH(xorg-module-dir,
@@ -56,6 +56,13 @@ AC_ARG_WITH(xorg-module-dir,
 inputdir=${moduledir}/input
 AC_SUBST(inputdir)
 
+AC_ARG_WITH(xorg-conf-dir,
+            AC_HELP_STRING([--with-xorg-conf-dir=DIR],
+                           [Default xorg.conf.d directory [[default=$prefix/share/X11/xorg.conf.d/]]]),
+            [xorgconfdir="$withval"],
+            [xorgconfdir="$prefix/share/X11/xorg.conf.d"])
+AC_SUBST(xorgconfdir)
+
 # X Server SDK location is required to install header files
 sdkdir=`$PKG_CONFIG --variable=sdkdir xorg-server`
 
@@ -71,5 +78,6 @@ AC_CONFIG_FILES([Makefile
 		 include/Makefile
 		 src/Makefile
 		 man/Makefile
+		 test/Makefile
 		 xorg-libinput.pc])
 AC_OUTPUT

include/libinput-properties.h

@@ -27,15 +27,51 @@
 /* Tapping enabled/disabled: BOOL, 1 value */
 #define LIBINPUT_PROP_TAP "libinput Tapping Enabled"
 
+/* Tapping default enabled/disabled: BOOL, 1 value, read-only */
+#define LIBINPUT_PROP_TAP_DEFAULT "libinput Tapping Enabled Default"
+
+/* Tap drag enabled/disabled: BOOL, 1 value */
+#define LIBINPUT_PROP_TAP_DRAG "libinput Tapping Drag Enabled"
+
+/* Tap drag default enabled/disabled: BOOL, 1 value */
+#define LIBINPUT_PROP_TAP_DRAG_DEFAULT "libinput Tapping Drag Enabled Default"
+
+/* Tap drag lock enabled/disabled: BOOL, 1 value */
+#define LIBINPUT_PROP_TAP_DRAG_LOCK "libinput Tapping Drag Lock Enabled"
+
+/* Tap drag lock default enabled/disabled: BOOL, 1 value */
+#define LIBINPUT_PROP_TAP_DRAG_LOCK_DEFAULT "libinput Tapping Drag Lock Enabled Default"
+
 /* Calibration matrix: FLOAT, 9 values of a 3x3 matrix, in rows */
 #define LIBINPUT_PROP_CALIBRATION "libinput Calibration Matrix"
 
+/* Calibration matrix: FLOAT, 9 values of a 3x3 matrix, in rows, read-only*/
+#define LIBINPUT_PROP_CALIBRATION_DEFAULT "libinput Calibration Matrix Default"
+
 /* Pointer accel speed: FLOAT, 1 value, 32 bit */
 #define LIBINPUT_PROP_ACCEL "libinput Accel Speed"
 
+/* Pointer accel speed: FLOAT, 1 value, 32 bit, read-only*/
+#define LIBINPUT_PROP_ACCEL_DEFAULT "libinput Accel Speed Default"
+
+/* Pointer accel profile: BOOL, 2 values in oder adaptive, flat,
+ * only one is enabled at a time at max, read-only */
+#define LIBINPUT_PROP_ACCEL_PROFILES_AVAILABLE "libinput Accel Profiles Available"
+
+/* Pointer accel profile: BOOL, 2 values in order adaptive, flat,
+   only one is enabled at a time at max, read-only */
+#define LIBINPUT_PROP_ACCEL_PROFILE_ENABLED_DEFAULT "libinput Accel Profile Enabled Default"
+
+/* Pointer accel profile: BOOL, 2 values in order adaptive, flat,
+   only one is enabled at a time at max */
+#define LIBINPUT_PROP_ACCEL_PROFILE_ENABLED "libinput Accel Profile Enabled"
+
 /* Natural scrolling: BOOL, 1 value */
 #define LIBINPUT_PROP_NATURAL_SCROLL "libinput Natural Scrolling Enabled"
 
+/* Natural scrolling: BOOL, 1 value, read-only */
+#define LIBINPUT_PROP_NATURAL_SCROLL_DEFAULT "libinput Natural Scrolling Enabled Default"
+
 /* Send-events mode: BOOL read-only, 2 values in order disabled,
    disabled-on-external-mouse */
 #define LIBINPUT_PROP_SENDEVENTS_AVAILABLE "libinput Send Events Modes Available"
@@ -44,9 +80,16 @@
    disabled-on-external-mouse */
 #define LIBINPUT_PROP_SENDEVENTS_ENABLED "libinput Send Events Mode Enabled"
 
+/* Send-events mode: BOOL, 2 values in order disabled,
+   disabled-on-external-mouse, read-only */
+#define LIBINPUT_PROP_SENDEVENTS_ENABLED_DEFAULT "libinput Send Events Mode Enabled Default"
+
 /* Left-handed enabled/disabled: BOOL, 1 value */
 #define LIBINPUT_PROP_LEFT_HANDED "libinput Left Handed Enabled"
 
+/* Left-handed enabled/disabled: BOOL, 1 value, read-only */
+#define LIBINPUT_PROP_LEFT_HANDED_DEFAULT "libinput Left Handed Enabled Default"
+
 /* Scroll method: BOOL read-only, 3 values in order 2fg, edge, button.
    shows available scroll methods */
 #define LIBINPUT_PROP_SCROLL_METHODS_AVAILABLE "libinput Scroll Methods Available"
@@ -55,9 +98,16 @@
    only one is enabled at a time at max */
 #define LIBINPUT_PROP_SCROLL_METHOD_ENABLED "libinput Scroll Method Enabled"
 
+/* Scroll method: BOOL, 3 values in order 2fg, edge, button
+   only one is enabled at a time at max, read-only */
+#define LIBINPUT_PROP_SCROLL_METHOD_ENABLED_DEFAULT "libinput Scroll Method Enabled Default"
+
 /* Scroll button for button scrolling: 32-bit int, 1 value */
 #define LIBINPUT_PROP_SCROLL_BUTTON "libinput Button Scrolling Button"
 
+/* Scroll button for button scrolling: 32-bit int, 1 value, read-only */
+#define LIBINPUT_PROP_SCROLL_BUTTON_DEFAULT "libinput Button Scrolling Button Default"
+
 /* Click method: BOOL read-only, 2 values in order buttonareas, clickfinger
    shows available click methods */
 #define LIBINPUT_PROP_CLICK_METHODS_AVAILABLE "libinput Click Methods Available"
@@ -66,4 +116,30 @@
    only one enabled at a time at max */
 #define LIBINPUT_PROP_CLICK_METHOD_ENABLED "libinput Click Method Enabled"
 
+/* Click method: BOOL, 2 values in order buttonareas, clickfinger
+   only one enabled at a time at max, read-only */
+#define LIBINPUT_PROP_CLICK_METHOD_ENABLED_DEFAULT "libinput Click Method Enabled Default"
+
+/* Middle button emulation: BOOL, 1 value */
+#define LIBINPUT_PROP_MIDDLE_EMULATION_ENABLED "libinput Middle Emulation Enabled"
+
+/* Middle button emulation: BOOL, 1 value, read-only */
+#define LIBINPUT_PROP_MIDDLE_EMULATION_ENABLED_DEFAULT "libinput Middle Emulation Enabled Default"
+
+/* Disable while typing: BOOL, 1 value */
+#define LIBINPUT_PROP_DISABLE_WHILE_TYPING "libinput Disable While Typing Enabled"
+
+/* Disable while typing: BOOL, 1 value, read-only */
+#define LIBINPUT_PROP_DISABLE_WHILE_TYPING_DEFAULT "libinput Disable While Typing Enabled Default"
+
+/* Drag lock buttons, either:
+   CARD8, one value, the meta lock button, or
+   CARD8, n * 2 values, the drag lock pairs with n being the button and n+1
+   the target button number */
+#define LIBINPUT_PROP_DRAG_LOCK_BUTTONS "libinput Drag Lock Buttons"
+
+/* Horizontal scroll events enabled: BOOL, 1 value (0 or 1).
+ * If disabled, horizontal scroll events are discarded */
+#define LIBINPUT_PROP_HORIZ_SCROLL_ENABLED "libinput Horizonal Scroll Enabled"
+
 #endif /* _LIBINPUT_PROPERTIES_H_ */

man/libinput.man

@@ -12,6 +12,7 @@ libinput \- libinput-based X.Org input driver
 \ \ ...
 .B EndSection
 .fi
+
 .SH NOTE
 This is the man page for the X input driver. If you are looking for the
 library documentation, go to 
@@ -30,6 +31,7 @@ devices are configured through the
 directive (refer to __xconfigfile__(__filemansuffix__)) instead of manual
 per-device configuration. Devices configured in the
 __xconfigfile__(__filemansuffix__) are not hot-plug capable.
+
 .SH CONFIGURATION DETAILS
 Please refer to __xconfigfile__(__filemansuffix__) for general configuration
 details and for options that can be used with all input drivers.  This
@@ -42,14 +44,40 @@ are supported:
 .BI "Option \*qDevice\*q \*q" string \*q
 Specifies the device through which the device can be accessed.  This will 
 generally be of the form \*q/dev/input/eventX\*q, where X is some integer.
+When using
+.B InputClass
+directives, this option is set by the server.
 The mapping from device node to hardware is system-dependent. Property:
 "Device Node" (read-only).
 .TP 7
+.BI "Option \*qAccelProfile\*q \*q" string \*q
+Sets the pointer acceleration profile to the given profile. Permitted values
+are
+.BI adaptive,
+.BI flat.
+Not all devices support this option or all profiles. If a profile is
+unsupported, the default profile for this is used. For a description on the
+profiles and their behavior, see the libinput documentation.
+.TP 7
 .BI "Option \*qAccelSpeed\*q \*q" float \*q
 Sets the pointer acceleration speed within the range [-1, 1]
 .TP 7
+.BI "Option \*qButtonMapping\*q \*q" string \*q
+Sets the logical button mapping for this device, see
+XSetPointerMapping(__libmansuffix__). The string must be a
+space-separated list of button mappings in the order of the
+logical buttons on the device, starting with button 1.
+The default mapping is "1 2 3 ... 32". A mapping of 0
+deactivates the button. Multiple buttons can have the same mapping.
+Invalid mapping strings are discarded and the default mapping
+is used for all buttons. Buttons not specified in the user's mapping use the
+default mapping. See section
+.B BUTTON MAPPING
+for more details.
+.TP 7
 .BI "Option \*qCalibrationMatrix\*q \*q" string \*q
-A string of 9 space-separated floating point numbers.
+A string of 9 space-separated floating point numbers, in the order
+\*qa b c d e f g h i\*q.
 Sets the calibration matrix to the 3x3 matrix where the first row is (abc),
 the second row is (def) and the third row is (ghi).
 .TP 7
@@ -64,6 +92,10 @@ default click method for this device is used.
 .BI "Option \*qLeftHanded\*q \*q" bool \*q
 Enables left-handed button orientation, i.e. swapping left and right buttons.
 .TP 7
+.BI "Option \*qMiddleEmulation\*q \*q" bool \*q
+Enables middle button emulation. When enabled, pressing the left and right
+buttons simultaneously produces a middle mouse button click.
+.TP 7
 .BI "Option \*qNaturalScrolling\*q \*q" bool \*q
 Enables or disables natural scrolling behavior.
 .TP 7
@@ -84,25 +116,77 @@ Enables a scroll method. Permitted values are
 Not all devices support all options, if an option is unsupported, the
 default scroll option for this device is used.
 .TP 7
+.BI "Option \*qHorizontalScrolling\*q" bool \*q
+Disables horizontal scrolling. When disabled, this driver will discard any
+horizontal scroll events from libinput. Note that this does not disable
+horizontal scrolling, it merely discards the horizontal axis from any scroll
+events.
+.TP 7
 .BI "Option \*qSendEventsMode\*q \*q" (disabled|enabled|disabled-on-external-mouse) \*q
 Sets the send events mode to disabled, enabled, or "disable when an external
 mouse is connected".
 .TP 7
 .BI "Option \*qTapping\*q \*q" bool \*q
 Enables or disables tap-to-click behavior.
+.TP 7
+.BI "Option \*qTappingDrag\*q \*q" bool \*q
+Enables or disables drag during tapping behavior ("tap-and-drag"). When
+enabled, a tap followed by a finger held down causes a single button down
+only, all motions of that finger thus translate into dragging motion.
+Tap-and-drag requires option
+.B Tapping
+to be enabled.
+.TP 7
+.BI "Option \*qTappingDragLock\*q \*q" bool \*q
+Enables or disables drag lock during tapping behavior. When enabled, a
+finger up during tap-and-drag will not immediately release the button. If
+the finger is set down again within the timeout, the dragging process
+continues.
+.TP 7
+.BI "Option \*qDisableWhileTyping\*q \*q" bool \*q
+Indicates if the touchpad should be disabled while typing on the keyboard
+(this does not apply to modifier keys such as Ctrl or Alt).
+.TP 7
+.BI "Option \*qDragLockButtons\*q \*q" "L1 B1 L2 B2 ..." \*q
+Sets "drag lock buttons" that simulate a button logically down even when it has
+been physically released. To logically release a locked button, a second click
+of the same button is required.
+.IP
+If the option is a single button number, that button acts as the
+"meta" locking button for the next button number. See section
+.B BUTTON DRAG LOCK
+for details.
+.IP
+If the option is a list of button number pairs, the first number of each
+number pair is the lock button, the second number the logical button number
+to be locked. See section
+.B BUTTON DRAG LOCK
+for details.
+.IP
+For both meta and button pair configuration, the button numbers are
+device button numbers, i.e. the
+.B ButtonMapping
+applies after drag lock.
 .PP
 For all options, the options are only parsed if the device supports that
 configuration option. For all options, the default value is the one used by
 libinput. On configuration failure, the default value is applied.
 
 .SH SUPPORTED PROPERTIES
-The following properties are provided by the
+.B libinput
+exports runtime-configurable options as properties. If a property listed
+below is not available, the matching configuration option is not available
+on the device. This however does not imply that the feature is not available
+on the device. The following properties are provided by the
 .B libinput
 driver.
 .TP 7
 .BI "libinput Tapping Enabled"
 1 boolean value (8 bit, 0 or 1). 1 enables tapping
 .TP 7
+.BI "libinput Tapping Drag Lock Enabled"
+1 boolean value (8 bit, 0 or 1). 1 enables drag lock during tapping
+.TP 7
 .BI "libinput Calibration Matrix"
 9 32-bit float values, representing a 3x3 calibration matrix, order is row
 1, row 2, row 3
@@ -113,9 +197,105 @@ driver.
 .BI "libinput Natural Scrolling Enabled"
 1 boolean value (8 bit, 0 or 1). 1 enables natural scrolling
 .TP 7
-.BI "libinput Send Events Mode"
-1 32-bit value, defines the sendevent mode. See the libinput documentation
-for the allowed values.
+.BI "libinput Send Events Modes Available"
+2 boolean values (8 bit, 0 or 1), in order "disabled" and
+"disabled-on-external-mouse". Indicates which send-event modes are available
+on this device.
+.TP 7
+.BI "libinput Send Events Mode Enabled"
+2 boolean values (8 bit, 0 or 1), in order "disabled" and
+"disabled-on-external-mouse". Indicates which send-event modes is currently
+enabled on this device.
+.TP 7
+.BI "libinput Left Handed Enabled"
+1 boolean value (8 bit, 0 or 1). Indicates if left-handed mode is enabled or
+disabled.
+.TP 7
+.BI "libinput Scroll Methods Available"
+3 boolean values (8 bit, 0 or 1), in order "two-finger", "edge", "button".
+Indicates which scroll methods are available on this device.
+.TP 7
+.BI "libinput Scroll Method Enabled"
+3 boolean values (8 bit, 0 or 1), in order "two-finger", "edge", "button".
+Indicates which scroll method is currently enabled on this device.
+.TP 7
+.BI "libinput Button Scrolling Button"
+1 32-bit value. Sets the button number to use for button scrolling. This
+setting is independent of the scroll method, to enable button scrolling the
+method must be set to button-scrolling and a valid button must be set.
+.TP 7
+.BI "libinput Click Methods Available"
+2 boolean values (8 bit, 0 or 1), in order "buttonareas", "clickfinger".
+Indicates which click methods are available on this device.
+.TP 7
+.BI "libinput Click Methods Enabled"
+2 boolean values (8 bit, 0 or 1), in order "buttonareas", "clickfinger".
+Indicates which click methods are enabled on this device.
+.TP 7
+.BI "libinput Middle Emulation Enabled"
+1 boolean value (8 bit, 0 or 1). Indicates if middle emulation is enabled or
+disabled.
+.TP 7
+.BI "libinput Disable While Typing Enabled"
+1 boolean value (8 bit, 0 or 1). Indicates if disable while typing is
+enabled or disabled.
+.PP
+The above properties have a
+.BI "libinput <property name> Default"
+equivalent that indicates the default value for this setting on this device.
+.TP 7
+.BI "libinput Drag Lock Buttons"
+Either one 8-bit value specifying the meta drag lock button, or a list of
+button pairs. See section
+.B BUTTON DRAG LOCK
+for details.
+.TP 7
+.BI "libinput Horizontal Scrolling Enabled"
+1 boolean value (8 bit, 0 or 1). Indicates whether horizontal scrolling
+events are enabled or not.
+
+.SH BUTTON MAPPING
+X clients receive events with logical button numbers, where 1, 2, 3
+are usually interpreted as left, middle, right and logical buttons 4, 5, 6,
+7 are usually interpreted as scroll up, down, left, right. The fourth and
+fifth physical buttons on a device will thus send logical buttons 8 and 9.
+The
+.B ButtonMapping
+option adjusts the logical button mapping, it does not affect how a physical
+button is mapped to a logical button.
+.PP
+Traditionally, a device was set to left-handed button mode by applying a
+button mapping of
+.B "\*q3 2 1 ...\*q"
+On systems using the
+.B libinput
+__xservername__ input driver it is recommended to use the
+.B LeftHanded
+option instead.
+.PP
+The
+.B libinput
+__xservername__ input driver does not use the button mapping after setup.
+Use XSetPointerMapping(__libmansuffix__) to modify the button mapping at
+runtime.
+
+.SH BUTTON DRAG LOCK
+Button drag lock holds a button logically down even when the button itself
+has been physically released since. Button drag lock comes in two modes.
+.PP
+If in "meta" mode, a meta button click activates drag lock for the next
+button press of any other button. A button click in the future will keep
+that button held logically down until a subsequent click of that same
+button. The meta button events themselves are discarded. A separate meta
+button click is required each time a drag lock should be activated for a
+button in the future.
+.PP
+If in "pairs" mode, each button can be assigned a target locking button.
+On button click, the target lock button is held logically down until the
+next click of the same button. The button events themselves are discarded
+and only the target button events are sent.
+.TP
+This feature is provided by this driver, not by libinput.
 
 .SH AUTHORS
 Peter Hutterer

src/Makefile.am

@@ -30,8 +30,10 @@ AM_CPPFLAGS =-I$(top_srcdir)/include $(LIBINPUT_CFLAGS)
 
 @DRIVER_NAME@_drv_la_LTLIBRARIES = @DRIVER_NAME@_drv.la
 @DRIVER_NAME@_drv_la_LDFLAGS = -module -avoid-version
-@DRIVER_NAME@_drv_la_LIBADD = $(LIBINPUT_LIBS)
+@DRIVER_NAME@_drv_la_LIBADD = $(LIBINPUT_LIBS) libdraglock.la
 @DRIVER_NAME@_drv_ladir = @inputdir@
 
-@DRIVER_NAME@_drv_la_SOURCES = @DRIVER_NAME@.c
+@DRIVER_NAME@_drv_la_SOURCES = xf86libinput.c
 
+noinst_LTLIBRARIES = libdraglock.la
+libdraglock_la_SOURCES = draglock.c draglock.h

src/draglock.c

@@ -0,0 +1,282 @@
+/*
+ * Copyright © 2015 Red Hat, Inc.
+ *
+ * Permission to use, copy, modify, distribute, and sell this software
+ * and its documentation for any purpose is hereby granted without
+ * fee, provided that the above copyright notice appear in all copies
+ * and that both that copyright notice and this permission notice
+ * appear in supporting documentation, and that the name of Red Hat
+ * not be used in advertising or publicity pertaining to distribution
+ * of the software without specific, written prior permission.  Red
+ * Hat makes no representations about the suitability of this software
+ * for any purpose.  It is provided "as is" without express or implied
+ * warranty.
+ *
+ * THE AUTHORS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN
+ * NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
+ * OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
+ * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "draglock.h"
+
+#include <string.h>
+#include <stdlib.h>
+
+#define ARRAY_SIZE(a) (sizeof(a)/sizeof((a)[0]))
+
+static int
+draglock_parse_config(struct draglock *dl, const char *config)
+{
+    int button = 0, target = 0;
+    const char *str = NULL;
+    char *end_str = NULL;
+    int pairs[DRAGLOCK_MAX_BUTTONS] = {0};
+
+    if (!config)
+	    return 0;
+
+    /* empty string disables drag lock */
+    if (*config == '\0') {
+	    dl->mode = DRAGLOCK_DISABLED;
+	    return 0;
+    }
+
+    /* check for a single-number string first, config is "<int>" */
+    button = strtol(config, &end_str, 10);
+    if (*end_str == '\0') {
+	    if (button < 0 || button >= DRAGLOCK_MAX_BUTTONS)
+		    return 1;
+	    /* we allow for button 0 so stacked xorg.conf.d snippets can
+	     * disable the config again */
+	    if (button == 0) {
+		    dl->mode = DRAGLOCK_DISABLED;
+		    return 0;
+	    }
+
+	    return draglock_set_meta(dl, button);
+    }
+
+    dl->mode = DRAGLOCK_DISABLED;
+
+    /* check for a set of button pairs, config is
+     * "<int> <int> <int> <int>..." */
+    str = config;
+    while (*str != '\0') {
+	    button = strtol(str, &end_str, 10);
+	    if (*end_str == '\0')
+		    return 1;
+
+	    str = end_str;
+	    target = strtol(str, &end_str, 10);
+	    if (end_str == str)
+		    return 1;
+	    if (button <= 0 || button >= DRAGLOCK_MAX_BUTTONS || target >= DRAGLOCK_MAX_BUTTONS)
+		    return 1;
+
+	    pairs[button] = target;
+	    str = end_str;
+    }
+
+    return draglock_set_pairs(dl, pairs, ARRAY_SIZE(pairs));
+}
+
+int
+draglock_init_from_string(struct draglock *dl, const char *config)
+{
+	dl->mode = DRAGLOCK_DISABLED;
+
+	dl->meta_button = 0;
+	dl->meta_state = false;
+	memset(dl->lock_pair, 0, sizeof(dl->lock_pair));
+	memset(dl->lock_state, 0, sizeof(dl->lock_state));
+
+	return draglock_parse_config(dl, config);
+}
+
+enum draglock_mode
+draglock_get_mode(const struct draglock *dl)
+{
+	return dl->mode;
+}
+
+int
+draglock_get_meta(const struct draglock *dl)
+{
+	if (dl->mode == DRAGLOCK_META)
+		return dl->meta_button;
+	return 0;
+}
+
+size_t
+draglock_get_pairs(const struct draglock *dl, int *array, size_t sz)
+{
+	unsigned int i;
+	size_t last = 0;
+
+	if (dl->mode != DRAGLOCK_PAIRS)
+		return 0;
+
+	/* size 1 array with the meta button */
+	if (dl->meta_button) {
+		*array = dl->meta_button;
+		return 1;
+	}
+
+	/* size N array with a[0] == 0, the rest ordered by button number */
+	memset(array, 0, sz * sizeof(array[0]));
+	for (i = 0; i < sz && i < ARRAY_SIZE(dl->lock_pair); i++) {
+		array[i] = dl->lock_pair[i];
+		if (array[i] != 0 && i > last)
+			last = i;
+	}
+	return last;
+}
+
+int
+draglock_set_meta(struct draglock *dl, int meta_button)
+{
+	if (meta_button < 0 || meta_button >= DRAGLOCK_MAX_BUTTONS)
+		return 1;
+
+	dl->meta_button = meta_button;
+	dl->mode = meta_button ? DRAGLOCK_META : DRAGLOCK_DISABLED;
+
+	return 0;
+}
+
+int
+draglock_set_pairs(struct draglock *dl, const int *array, size_t sz)
+{
+	unsigned int i;
+
+	if (sz == 0 || array[0] != 0)
+		return 1;
+
+	for (i = 0; i < sz; i++) {
+		if (array[i] < 0 || array[i] >= DRAGLOCK_MAX_BUTTONS)
+			return 1;
+	}
+
+	dl->mode = DRAGLOCK_DISABLED;
+	for (i = 0; i < sz; i++) {
+		dl->lock_pair[i] = array[i];
+		if (dl->lock_pair[i])
+			dl->mode = DRAGLOCK_PAIRS;
+	}
+
+	return 0;
+}
+
+static int
+draglock_filter_meta(struct draglock *dl, int *button, int *press)
+{
+	int b = *button,
+	    is_press = *press;
+
+	if (b == dl->meta_button) {
+		if (is_press)
+			dl->meta_state = true;
+		*button = 0;
+		return 0;
+	}
+
+	switch (dl->lock_state[b]) {
+	case DRAGLOCK_BUTTON_STATE_NONE:
+		if (dl->meta_state && is_press) {
+			dl->lock_state[b] = DRAGLOCK_BUTTON_STATE_DOWN_1;
+			dl->meta_state = false;
+		}
+		break;
+	case DRAGLOCK_BUTTON_STATE_DOWN_1:
+		if (!is_press) {
+			dl->lock_state[b] = DRAGLOCK_BUTTON_STATE_UP_1;
+			b = 0;
+		}
+		break;
+	case DRAGLOCK_BUTTON_STATE_UP_1:
+		if (is_press) {
+			dl->lock_state[b] = DRAGLOCK_BUTTON_STATE_DOWN_2;
+			b = 0;
+		}
+		break;
+	case DRAGLOCK_BUTTON_STATE_DOWN_2:
+		if (!is_press) {
+			dl->lock_state[b] = DRAGLOCK_BUTTON_STATE_NONE;
+		}
+		break;
+	}
+
+	*button = b;
+
+	return 0;
+}
+
+static int
+draglock_filter_pair(struct draglock *dl, int *button, int *press)
+{
+	int b = *button,
+	    is_press = *press;
+
+	if (dl->lock_pair[b] == 0)
+		return 0;
+
+	switch (dl->lock_state[b]) {
+	case DRAGLOCK_BUTTON_STATE_NONE:
+		if (is_press) {
+			dl->lock_state[b] = DRAGLOCK_BUTTON_STATE_DOWN_1;
+			b = dl->lock_pair[b];
+		}
+		break;
+	case DRAGLOCK_BUTTON_STATE_DOWN_1:
+		if (!is_press) {
+			dl->lock_state[b] = DRAGLOCK_BUTTON_STATE_UP_1;
+			b = 0;
+		}
+		break;
+	case DRAGLOCK_BUTTON_STATE_UP_1:
+		if (is_press) {
+			dl->lock_state[b] = DRAGLOCK_BUTTON_STATE_DOWN_2;
+			b = 0;
+		}
+		break;
+	case DRAGLOCK_BUTTON_STATE_DOWN_2:
+		if (!is_press) {
+			dl->lock_state[b] = DRAGLOCK_BUTTON_STATE_NONE;
+			b = dl->lock_pair[b];
+		}
+		break;
+	}
+
+	*button = b;
+
+	return 0;
+}
+
+int
+draglock_filter_button(struct draglock *dl, int *button, int *is_press)
+{
+	if (*button == 0)
+		return 0;
+
+	switch(dl->mode) {
+	case DRAGLOCK_DISABLED:
+		return 0;
+	case DRAGLOCK_META:
+		return draglock_filter_meta(dl, button, is_press);
+	case DRAGLOCK_PAIRS:
+		return draglock_filter_pair(dl, button, is_press);
+	default:
+		abort();
+		break;
+	}
+
+	return 0;
+}

src/draglock.h

@@ -0,0 +1,159 @@
+/*
+ * Copyright © 2015 Red Hat, Inc.
+ *
+ * Permission to use, copy, modify, distribute, and sell this software
+ * and its documentation for any purpose is hereby granted without
+ * fee, provided that the above copyright notice appear in all copies
+ * and that both that copyright notice and this permission notice
+ * appear in supporting documentation, and that the name of Red Hat
+ * not be used in advertising or publicity pertaining to distribution
+ * of the software without specific, written prior permission.  Red
+ * Hat makes no representations about the suitability of this software
+ * for any purpose.  It is provided "as is" without express or implied
+ * warranty.
+ *
+ * THE AUTHORS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN
+ * NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
+ * OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
+ * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#ifndef DRAGLOCK_H
+#define DRAGLOCK_H 1
+
+#include <stdbool.h>
+#include <stdlib.h>
+
+/* 32 buttons are enough for everybody™
+ * Note that this is the limit of physical buttons as well as the highest
+ * allowed target button.
+ */
+#define DRAGLOCK_MAX_BUTTONS 32
+
+enum draglock_mode
+{
+	DRAGLOCK_DISABLED,
+	DRAGLOCK_META,
+	DRAGLOCK_PAIRS
+};
+
+enum draglock_button_state
+{
+	DRAGLOCK_BUTTON_STATE_NONE,
+	DRAGLOCK_BUTTON_STATE_DOWN_1,
+	DRAGLOCK_BUTTON_STATE_UP_1,
+	DRAGLOCK_BUTTON_STATE_DOWN_2,
+};
+
+struct draglock
+{
+	enum draglock_mode mode;
+	int meta_button;			/* meta key to lock any button */
+	bool meta_state;			/* meta_button state */
+	unsigned int lock_pair[DRAGLOCK_MAX_BUTTONS + 1];/* specify a meta/lock pair */
+	enum draglock_button_state lock_state[DRAGLOCK_MAX_BUTTONS + 1];	/* state of any locked buttons */
+};
+
+/**
+ * Initialize the draglock struct based on the config string. The string is
+ * either a single number to configure DRAGLOCK_META mode or a list of
+ * number pairs, with pair[0] as button and pair[1] as target lock number to
+ * configure DRAGLOCK_PAIRS mode.
+ *
+ * If config is NULL, the empty string, "0" or an even-numbered list of 0,
+ * the drag lock mode is DRAGLOCK_DISABLED.
+ *
+ * @return 0 on success or nonzero on error
+ */
+int
+draglock_init_from_string(struct draglock *dl, const char *config);
+
+/**
+ * Get the current drag lock mode.
+ *
+ * If the mode is DRAGLOCK_META, a meta button click will cause the next
+ * subsequent button click to be held logically down until the release of
+ * the second button click of that same button. Events from the meta button
+ * are always discarded.
+ *
+ * If the mode is DRAGLOCK_PAIRS, any button may be configured with a
+ * 'target' button number. A click of that button causes the target button
+ * to be held logically down until the release of the second button click.
+ */
+enum draglock_mode
+draglock_get_mode(const struct draglock *dl);
+
+/**
+ * @return the meta button number or 0 if the current mode is not
+ * DRAGLOCK_META.
+ */
+int
+draglock_get_meta(const struct draglock *dl);
+
+/**
+ * Get the drag lock button mapping pairs. The array is filled with the
+ * button number as index and the mapped target button number as value, i.e.
+ * array[3] == 8 means button 3 will draglock button 8.
+ *
+ * A value of 0 indicates draglock is disabled for that button.
+ *
+ * @note Button numbers start at 1, array[0] is always 0.
+ *
+ * @param[in|out] array Caller-allocated array to hold the button mappings.
+ * @param[in] sz Maximum number of elements in array
+ *
+ * @return The number of valid elements in array or 0 if the current mode is
+ * not DRAGLOCK_PAIRS
+ */
+size_t
+draglock_get_pairs(const struct draglock *dl, int *array, size_t sz);
+
+/**
+ * Set the drag lock config to the DRAGLOCK_META mode, with the given
+ * button as meta button.
+ *
+ * If the button is 0 the mode becomes DRAGLOCK_DISABLED.
+ *
+ * @return 0 on success, nonzero otherwise
+ */
+int
+draglock_set_meta(struct draglock *dl, int meta_button);
+
+/**
+ * Set the drag lock config to the DRAGLOCK_PAIRS mode. The array
+ * must be filled with the button number as index and the mapped target
+ * button number as value, i.e.
+ * array[3] == 8 means button 3 will draglock button 8.
+ *
+ * A value of 0 indicates draglock is disabled for that button. If all
+ * buttons are 0, the mode becomes DRAGLOCK_DISABLED.
+ *
+ * @note Button numbers start at 1, array[0] is always 0.
+ *
+ * @return 0 on successor nonzero otherwise
+ */
+int
+draglock_set_pairs(struct draglock *dl, const int *array, size_t sz);
+
+/**
+ * Process the given button event through the drag lock state machine.
+ * If the event is to be discarded by the caller, button is set to 0.
+ * Otherwise, button is set to the button event to process and is_press is
+ * set to the button state to process.
+ *
+ * @param[in|out] button The button number to process
+ * @param[in|out] is_press nonzero for press, zero for release
+ *
+ * @return 0 on success or 1 on error
+ */
+int
+draglock_filter_button(struct draglock *dl, int *button, int *is_press);
+
+#endif /* DRAGLOCK_H */

test/.gitignore

@@ -0,0 +1 @@
+test-draglock

test/Makefile.am

@@ -0,0 +1,13 @@
+AM_CPPFLAGS = $(XORG_CFLAGS) \
+	      $(CWARNFLAGS) \
+	      -I$(top_srcdir)/include \
+	      -I$(top_srcdir)/src
+
+tests = test-draglock
+
+noinst_PROGRAMS = $(tests)
+
+test_draglock_SOURCES = test-draglock.c
+test_draglock_LDADD = ../src/libdraglock.la
+
+TESTS = $(tests)

test/test-draglock.c

@@ -0,0 +1,540 @@
+/*
+ * Copyright © 2013-2015 Red Hat, Inc.
+ *
+ * Permission to use, copy, modify, distribute, and sell this software
+ * and its documentation for any purpose is hereby granted without
+ * fee, provided that the above copyright notice appear in all copies
+ * and that both that copyright notice and this permission notice
+ * appear in supporting documentation, and that the name of Red Hat
+ * not be used in advertising or publicity pertaining to distribution
+ * of the software without specific, written prior permission.  Red
+ * Hat makes no representations about the suitability of this software
+ * for any purpose.  It is provided "as is" without express or implied
+ * warranty.
+ *
+ * THE AUTHORS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN
+ * NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
+ * OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
+ * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "draglock.h"
+
+#include <assert.h>
+#include <string.h>
+
+static void
+test_config_empty(void)
+{
+	struct draglock dl;
+	int rc;
+
+	rc = draglock_init_from_string(&dl, NULL);
+	assert(dl.mode == DRAGLOCK_DISABLED);
+	assert(rc == 0);
+}
+
+static void
+test_config_invalid(void)
+{
+	struct draglock dl;
+	int rc;
+
+	/* no trailing space */
+	rc = draglock_init_from_string(&dl, "1 ");
+	assert(rc != 0);
+	assert(dl.mode == DRAGLOCK_DISABLED);
+
+	rc = draglock_init_from_string(&dl, "256");
+	assert(rc != 0);
+	assert(dl.mode == DRAGLOCK_DISABLED);
+
+	rc = draglock_init_from_string(&dl, "-1");
+	assert(rc != 0);
+	assert(dl.mode == DRAGLOCK_DISABLED);
+
+	rc = draglock_init_from_string(&dl, "1 2 3");
+	assert(rc != 0);
+	assert(dl.mode == DRAGLOCK_DISABLED);
+
+	rc = draglock_init_from_string(&dl, "0 2");
+	assert(rc != 0);
+	assert(dl.mode == DRAGLOCK_DISABLED);
+
+	rc = draglock_init_from_string(&dl, "0 0");
+	assert(rc != 0);
+	assert(dl.mode == DRAGLOCK_DISABLED);
+}
+
+static void
+test_config_disable(void)
+{
+	struct draglock dl;
+	int rc;
+
+	rc = draglock_init_from_string(&dl, "");
+	assert(rc == 0);
+	assert(dl.mode == DRAGLOCK_DISABLED);
+
+	rc = draglock_init_from_string(&dl, "0");
+	assert(rc == 0);
+	assert(dl.mode == DRAGLOCK_DISABLED);
+}
+
+static void
+test_config_meta_button(void)
+{
+	struct draglock dl;
+	int rc;
+
+	rc = draglock_init_from_string(&dl, "1");
+	assert(rc == 0);
+	assert(dl.mode == DRAGLOCK_META);
+	assert(dl.meta_button == 1);
+
+	rc = draglock_init_from_string(&dl, "2");
+	assert(rc == 0);
+	assert(dl.mode == DRAGLOCK_META);
+	assert(dl.meta_button == 2);
+
+	rc = draglock_init_from_string(&dl, "10");
+	assert(rc == 0);
+	assert(dl.mode == DRAGLOCK_META);
+	assert(dl.meta_button == 10);
+}
+
+static void
+test_config_button_pairs(void)
+{
+	struct draglock dl;
+	int rc;
+
+	rc = draglock_init_from_string(&dl, "1 1");
+	assert(rc == 0);
+	assert(dl.mode == DRAGLOCK_PAIRS);
+
+	rc = draglock_init_from_string(&dl, "1 2 3 4 5 6 7 8");
+	assert(rc == 0);
+	assert(dl.mode == DRAGLOCK_PAIRS);
+
+	rc = draglock_init_from_string(&dl, "1 2 3 4 5 0 7 8");
+	assert(rc == 0);
+	assert(dl.mode == DRAGLOCK_PAIRS);
+
+	/* all disabled */
+	rc = draglock_init_from_string(&dl, "1 0 3 0 5 0 7 0");
+	assert(rc == 0);
+	assert(dl.mode == DRAGLOCK_DISABLED);
+}
+
+static void
+test_config_get(void)
+{
+	struct draglock dl;
+	int rc;
+	const int sz = 32;
+	int map[sz];
+
+	draglock_init_from_string(&dl, "");
+	rc = draglock_get_meta(&dl);
+	assert(rc == 0);
+	rc = draglock_get_pairs(&dl, map, sz);
+	assert(rc == 0);
+
+	draglock_init_from_string(&dl, "8");
+	rc = draglock_get_meta(&dl);
+	assert(rc == 8);
+	rc = draglock_get_pairs(&dl, map, sz);
+	assert(rc == 0);
+
+	draglock_init_from_string(&dl, "1 2 3 4 5 6");
+	rc = draglock_get_meta(&dl);
+	assert(rc == 0);
+	rc = draglock_get_pairs(&dl, map, sz);
+	assert(rc == 5);
+	assert(map[0] == 0);
+	assert(map[1] == 2);
+	assert(map[2] == 0);
+	assert(map[3] == 4);
+	assert(map[4] == 0);
+	assert(map[5] == 6);
+}
+
+static void
+test_set_meta(void)
+{
+	struct draglock dl;
+	int rc;
+
+	draglock_init_from_string(&dl, "");
+
+	rc = draglock_set_meta(&dl, 0);
+	assert(rc == 0);
+	assert(dl.mode == DRAGLOCK_DISABLED);
+
+	rc = draglock_set_meta(&dl, 1);
+	assert(rc == 0);
+	assert(dl.mode == DRAGLOCK_META);
+
+	rc = draglock_set_meta(&dl, -1);
+	assert(rc == 1);
+	rc = draglock_set_meta(&dl, 32);
+	assert(rc == 1);
+}
+
+static void
+test_set_pairs(void)
+{
+	struct draglock dl;
+	int rc;
+	const int sz = 32;
+	int map[sz];
+
+	draglock_init_from_string(&dl, "");
+	memset(map, 0, sizeof(map));
+
+	rc = draglock_set_pairs(&dl, map, sz);
+	assert(rc == 0);
+	assert(dl.mode == DRAGLOCK_DISABLED);
+
+	rc = draglock_set_pairs(&dl, map, 1);
+	assert(rc == 0);
+	assert(dl.mode == DRAGLOCK_DISABLED);
+
+	map[0] = 1;
+	rc = draglock_set_pairs(&dl, map, 1);
+	assert(rc == 1);
+
+	map[0] = 0;
+	map[1] = 2;
+	rc = draglock_set_pairs(&dl, map, sz);
+	assert(rc == 0);
+	assert(dl.mode == DRAGLOCK_PAIRS);
+
+	map[0] = 0;
+	map[1] = 0;
+	map[10] = 8;
+	rc = draglock_set_pairs(&dl, map, sz);
+	assert(rc == 0);
+	assert(dl.mode == DRAGLOCK_PAIRS);
+}
+
+static void
+test_filter_meta_passthrough(void)
+{
+	struct draglock dl;
+	int rc;
+	int button, press;
+	int i;
+
+	rc = draglock_init_from_string(&dl, "10");
+
+	for (i = 0; i < 10; i++) {
+		button = i;
+		press = 1;
+
+		rc = draglock_filter_button(&dl, &button, &press);
+		assert(rc == 0);
+		assert(button == i);
+		assert(press == 1);
+
+		press = 1;
+		rc = draglock_filter_button(&dl, &button, &press);
+		assert(rc == 0);
+		assert(button == i);
+		assert(press == 1);
+	}
+}
+
+static void
+test_filter_meta_click_meta_only(void)
+{
+	struct draglock dl;
+	int rc;
+	int button, press;
+
+	rc = draglock_init_from_string(&dl, "10");
+
+	button = 10;
+	press = 1;
+
+	rc = draglock_filter_button(&dl, &button, &press);
+	assert(rc == 0);
+	assert(button == 0);
+
+	button = 10;
+	press = 0;
+	rc = draglock_filter_button(&dl, &button, &press);
+	assert(rc == 0);
+	assert(button == 0);
+}
+
+static void
+test_filter_meta(void)
+{
+	struct draglock dl;
+	int rc;
+	int button, press;
+	int i;
+
+	rc = draglock_init_from_string(&dl, "10");
+
+	for (i = 1; i < 10; i++) {
+		/* meta down */
+		button = 10;
+		press = 1;
+		rc = draglock_filter_button(&dl, &button, &press);
+		assert(rc == 0);
+		assert(button == 0);
+
+		/* meta up */
+		button = 10;
+		press = 0;
+		rc = draglock_filter_button(&dl, &button, &press);
+		assert(rc == 0);
+		assert(button == 0);
+
+		/* button down -> passthrough */
+		button = i;
+		press = 1;
+		rc = draglock_filter_button(&dl, &button, &press);
+		assert(rc == 0);
+		assert(button == i);
+
+		/* button up -> eaten */
+		button = i;
+		press = 0;
+		rc = draglock_filter_button(&dl, &button, &press);
+		assert(rc == 0);
+		assert(button == 0);
+
+		/* button down -> eaten */
+		button = i;
+		press = 1;
+		rc = draglock_filter_button(&dl, &button, &press);
+		assert(rc == 0);
+		assert(button == 0);
+
+		/* button up -> passthrough */
+		button = i;
+		press = 0;
+		rc = draglock_filter_button(&dl, &button, &press);
+		assert(rc == 0);
+		assert(button == i);
+		assert(press == 0);
+	}
+}
+
+static void
+test_filter_meta_extra_click(void)
+{
+	struct draglock dl;
+	int rc;
+	int button, press;
+	int i;
+
+	rc = draglock_init_from_string(&dl, "10");
+
+	for (i = 1; i < 10; i++) {
+		/* meta down */
+		button = 10;
+		press = 1;
+		rc = draglock_filter_button(&dl, &button, &press);
+		assert(rc == 0);
+		assert(button == 0);
+
+		/* meta up */
+		button = 10;
+		press = 0;
+		rc = draglock_filter_button(&dl, &button, &press);
+		assert(rc == 0);
+		assert(button == 0);
+
+		/* button down -> passthrough */
+		button = i;
+		press = 1;
+		rc = draglock_filter_button(&dl, &button, &press);
+		assert(rc == 0);
+		assert(button == i);
+
+		/* button up -> eaten */
+		button = i;
+		press = 0;
+		rc = draglock_filter_button(&dl, &button, &press);
+		assert(rc == 0);
+		assert(button == 0);
+
+		/* meta down */
+		button = 10;
+		press = 1;
+		rc = draglock_filter_button(&dl, &button, &press);
+		assert(rc == 0);
+		assert(button == 0);
+
+		/* meta up */
+		button = 10;
+		press = 0;
+		rc = draglock_filter_button(&dl, &button, &press);
+		assert(rc == 0);
+		assert(button == 0);
+
+		/* button down -> eaten */
+		button = i;
+		press = 1;
+		rc = draglock_filter_button(&dl, &button, &press);
+		assert(rc == 0);
+		assert(button == 0);
+
+		/* button up -> passthrough */
+		button = i;
+		press = 0;
+		rc = draglock_filter_button(&dl, &button, &press);
+		assert(rc == 0);
+		assert(button == i);
+		assert(press == 0);
+	}
+}
+
+static void
+test_filter_meta_interleaved(void)
+{
+	struct draglock dl;
+	int rc;
+	int button, press;
+	int i;
+
+	rc = draglock_init_from_string(&dl, "10");
+
+	for (i = 1; i < 10; i++) {
+		/* meta down */
+		button = 10;
+		press = 1;
+		rc = draglock_filter_button(&dl, &button, &press);
+		assert(rc == 0);
+		assert(button == 0);
+
+		/* meta up */
+		button = 10;
+		press = 0;
+		rc = draglock_filter_button(&dl, &button, &press);
+		assert(rc == 0);
+		assert(button == 0);
+
+		/* button down -> passthrough */
+		button = i;
+		press = 1;
+		rc = draglock_filter_button(&dl, &button, &press);
+		assert(rc == 0);
+		assert(button == i);
+
+		/* button up -> eaten */
+		button = i;
+		press = 0;
+		rc = draglock_filter_button(&dl, &button, &press);
+		assert(rc == 0);
+		assert(button == 0);
+	}
+
+	for (i = 0; i < 10; i++) {
+		/* button down -> eaten */
+		button = i;
+		press = 1;
+		rc = draglock_filter_button(&dl, &button, &press);
+		assert(rc == 0);
+		assert(button == 0);
+
+		/* button up -> passthrough */
+		button = i;
+		press = 0;
+		rc = draglock_filter_button(&dl, &button, &press);
+		assert(rc == 0);
+		assert(button == i);
+		assert(press == 0);
+	}
+}
+
+static void
+test_filter_pairs(void)
+{
+	struct draglock dl;
+	int rc;
+	int button, press;
+	int i;
+
+	rc = draglock_init_from_string(&dl, "1 11 2 0 3 13 4 0 5 15 6 0 7 17 8 0 9 19");
+
+	for (i = 1; i < 10; i++) {
+		button = i;
+		press = 1;
+
+		rc = draglock_filter_button(&dl, &button, &press);
+		assert(rc == 0);
+		if (i % 2)
+			assert(button == i + 10);
+		else
+			assert(button == i);
+		assert(press == 1);
+
+		button = i;
+		press = 0;
+		rc = draglock_filter_button(&dl, &button, &press);
+		assert(rc == 0);
+		if (i % 2) {
+			assert(button == 0);
+		} else {
+			assert(button == i);
+			assert(press == 0);
+		}
+	}
+
+	for (i = 1; i < 10; i++) {
+		button = i;
+		press = 1;
+
+		rc = draglock_filter_button(&dl, &button, &press);
+		assert(rc == 0);
+		if (i % 2) {
+			assert(button == 0);
+		} else {
+			assert(button == i);
+			assert(press == 1);
+		}
+
+		button = i;
+		press = 0;
+		rc = draglock_filter_button(&dl, &button, &press);
+		assert(rc == 0);
+		if (i % 2)
+			assert(button == i + 10);
+		else
+			assert(button == i);
+		assert(press == 0);
+	}
+}
+
+int
+main(int argc, char **argv)
+{
+	test_config_empty();
+	test_config_invalid();
+	test_config_disable();
+	test_config_meta_button();
+	test_config_button_pairs();
+
+	test_config_get();
+	test_set_meta();
+	test_set_pairs();
+
+	test_filter_meta_passthrough();
+	test_filter_meta_click_meta_only();
+	test_filter_meta();
+	test_filter_meta_extra_click();
+	test_filter_meta_interleaved();
+
+	test_filter_pairs();
+
+	return 0;
+}