Ignore test devices for libinput contexts not run from the test suite

Add a LIBINPUT_TEST_DEVICE udev parameter to test devices created by
the test suite. When an application tries to add such a device to the
path backend or when the udev backend discovers such a device, it will
be ignored. Only the context when run via the test suite will actually
handle these devices.

Doing this will enable a user to run the libinput test suite on a system
running libinput without having the test suite devices interfering with
the actual system.

Note that X.org users running an input device driver that is not the
libinput X input driver will still need to manually configure the X
server to ignore such devices (see test/50-litest.conf).

Signed-off-by: Jonas Ådahl <jadahl@gmail.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>

src/libinput-private.h

@@ -292,6 +292,9 @@ open_restricted(struct libinput *libinput,
 void
 close_restricted(struct libinput *libinput, int fd);
 
+bool
+ignore_litest_test_suite_device(struct udev_device *device);
+
 void
 libinput_seat_init(struct libinput_seat *seat,
 		   struct libinput *libinput,

src/libinput.c

@@ -1020,6 +1020,16 @@ close_restricted(struct libinput *libinput, int fd)
 	return libinput->interface->close_restricted(fd, libinput->user_data);
 }
 
+bool
+ignore_litest_test_suite_device(struct udev_device *device)
+{
+	if (!getenv("LIBINPUT_RUNNING_TEST_SUITE") &&
+	    udev_device_get_property_value(device, "LIBINPUT_TEST_DEVICE"))
+		return true;
+
+	return false;
+}
+
 void
 libinput_seat_init(struct libinput_seat *seat,
 		   struct libinput *libinput,

src/path.c

@@ -343,6 +343,11 @@ libinput_path_add_device(struct libinput *libinput,
 		return NULL;
 	}
 
+	if (ignore_litest_test_suite_device(udev_device)) {
+		udev_device_unref(udev_device);
+		return NULL;
+	}
+
 	device = path_create_device(libinput, udev_device, NULL);
 	udev_device_unref(udev_device);
 	return device;

src/udev-seat.c

@@ -62,6 +62,9 @@ device_added(struct udev_device *udev_device,
 	if (!streq(device_seat, input->seat_id))
 		return 0;
 
+	if (ignore_litest_test_suite_device(udev_device))
+		return 0;
+
 	devnode = udev_device_get_devnode(udev_device);
 
 	/* Search for matching logical seat */

test/Makefile.am

@@ -46,7 +46,8 @@ liblitest_la_SOURCES = \
 liblitest_la_LIBADD = $(top_builddir)/src/libinput-util.la
 liblitest_la_CFLAGS = $(AM_CFLAGS) \
 	      -DLIBINPUT_MODEL_QUIRKS_UDEV_RULES_FILE="\"$(abs_top_builddir)/udev/90-libinput-model-quirks-litest.rules\"" \
-	      -DLIBINPUT_MODEL_QUIRKS_UDEV_HWDB_FILE="\"$(abs_top_srcdir)/udev/90-libinput-model-quirks.hwdb\""
+	      -DLIBINPUT_MODEL_QUIRKS_UDEV_HWDB_FILE="\"$(abs_top_srcdir)/udev/90-libinput-model-quirks.hwdb\"" \
+	      -DLIBINPUT_TEST_DEVICE_RULES_FILE="\"$(abs_top_srcdir)/udev/80-libinput-test-device.rules\""
 if HAVE_LIBUNWIND
 liblitest_la_LIBADD += $(LIBUNWIND_LIBS) -ldl
 liblitest_la_CFLAGS += $(LIBUNWIND_CFLAGS)

test/litest.c

@@ -57,6 +57,8 @@
 	"/91-litest-model-quirks-REMOVEME.rules"
 #define UDEV_MODEL_QUIRKS_HWDB_FILE UDEV_HWDB_D \
 	"/91-litest-model-quirks-REMOVEME.hwdb"
+#define UDEV_TEST_DEVICE_RULE_FILE UDEV_RULES_D \
+	"/91-litest-test-device-REMOVEME.rules"
 
 static int in_debugger = -1;
 static int verbose = 0;
@@ -955,6 +957,9 @@ litest_install_model_quirks(void)
 	litest_copy_file(UDEV_MODEL_QUIRKS_HWDB_FILE,
 			 LIBINPUT_MODEL_QUIRKS_UDEV_HWDB_FILE,
 			 warning);
+	litest_copy_file(UDEV_TEST_DEVICE_RULE_FILE,
+			 LIBINPUT_TEST_DEVICE_RULES_FILE,
+			 warning);
 }
 
 static inline void
@@ -962,6 +967,7 @@ litest_remove_model_quirks(void)
 {
 	unlink(UDEV_MODEL_QUIRKS_RULE_FILE);
 	unlink(UDEV_MODEL_QUIRKS_HWDB_FILE);
+	unlink(UDEV_TEST_DEVICE_RULE_FILE);
 }
 
 static void
@@ -2551,6 +2557,7 @@ main(int argc, char **argv)
 	list_init(&all_tests);
 
 	setenv("CK_DEFAULT_TIMEOUT", "10", 0);
+	setenv("LIBINPUT_RUNNING_TEST_SUITE", "1", 1);
 
 	mode = litest_parse_argv(argc, argv);
 	if (mode == LITEST_MODE_ERROR)

udev/.gitignore

@@ -1,3 +1,6 @@
 libinput-device-group
 libinput-model-quirks
-*.rules
+80-libinput-device-groups-litest.rules
+80-libinput-device-groups.rules
+90-libinput-model-quirks-litest.rules
+90-libinput-model-quirks.rules

udev/80-libinput-test-device.rules

@@ -0,0 +1 @@
+KERNELS=="*input*", ATTRS{name}=="litest *", ENV{LIBINPUT_TEST_DEVICE}="1"