From bcb6f22d89783418b70363d6a2fddefd450c441d Mon Sep 17 00:00:00 2001 From: Peter Hutterer Date: Tue, 3 Feb 2015 14:18:15 +1000 Subject: [PATCH] path: make sure udev devices are initialized before usage When creating uinput devices, we get the devnode from the kernel directly rather than through udev. When we add this to the path backend too quickly the udev_device we get may not be fully initialized and properties may be missing. This causes false test results. Avoid this by making sure the handle we have is initialized. This should never trigger on a real device anyway, even creating a device through litest is slow enough to avoid this issue. Only affected are the tests in misc.c where we create the uinput device directly. Nonetheless, handle this for the generic case so we don't run into heisenbugs later. Signed-off-by: Peter Hutterer Reviewed-by: Hans de Goede --- src/path.c | 26 +++++++++++++++++++++++--- 1 file changed, 23 insertions(+), 3 deletions(-) diff --git a/src/path.c b/src/path.c index dd70efc6..832a1fd8 100644 --- a/src/path.c +++ b/src/path.c @@ -291,14 +291,34 @@ libinput_path_create_context(const struct libinput_interface *interface, } static inline struct udev_device * -udev_device_from_devnode(struct udev *udev, const char *devnode) +udev_device_from_devnode(struct libinput *libinput, + struct udev *udev, + const char *devnode) { + struct udev_device *dev; struct stat st; + size_t count = 0; if (stat(devnode, &st) < 0) return NULL; - return udev_device_new_from_devnum(udev, 'c', st.st_rdev); + dev = udev_device_new_from_devnum(udev, 'c', st.st_rdev); + + while (dev && !udev_device_get_is_initialized(dev)) { + udev_device_unref(dev); + msleep(10); + dev = udev_device_new_from_devnum(udev, 'c', st.st_rdev); + + count++; + if (count > 10) { + log_bug_libinput(libinput, + "udev device never initialized (%s)\n", + devnode); + break; + } + } + + return dev; } LIBINPUT_EXPORT struct libinput_device * @@ -315,7 +335,7 @@ libinput_path_add_device(struct libinput *libinput, return NULL; } - udev_device = udev_device_from_devnode(udev, path); + udev_device = udev_device_from_devnode(libinput, udev, path); if (!udev_device) { log_bug_client(libinput, "Invalid path %s\n", path); return NULL;