Hi Benjamin On Wed, Jan 22, 2014 at 6:24 PM, Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx> wrote: > uinput is used in the xorg-integration-tests suite and in the wayland > test suite. These automated tests suites create many virtual input > devices and then hook something to read these newly created devices. > > Currently, uinput does not provide the created input device, which means > that we rely on an heuristic to guess which input node was created. > The problem is that is heuristic is subjected to races between different > uinput devices or even with physical devices. Having a way to retrieve > the sysfs path allows us to find without any doubts the event node. > > Signed-off-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx> > --- > > Hi guys, > > a new version of this patch with a brand new commit message. > Happy reviewing :) > > changes since v3: > - new commit message (I hope it will be better now) > - removed the -EAGAIN stuff thanks to the previous patch (not in v3) > - used "put_user(0, (char *)dest + len - 1);" instead of "copy_to_user(dest + len - 1, "\0", 1);" > - check if maxlen == 0 > > changes since v2: > - the ioctl returns only the device name, thus I renamed the ioctl to UI_GET_SYSNAME > - reordered uinput_str_to_user() arguments > - be sure to terminate the user string we send by \0 > - abort if udev->state is not UIST_CREATED > - dropped the patch 1/2 (adding resolution to uinput) because I think David has > already it in one of his queues (ABS2 IIRC) > > The corresponding libevdev patch is still here: > http://lists.freedesktop.org/archives/input-tools/2014-January/000757.html > > Cheers, > Benjamin > > drivers/input/misc/uinput.c | 42 ++++++++++++++++++++++++++++++++++++++++++ > include/linux/uinput.h | 2 ++ > include/uapi/linux/uinput.h | 13 ++++++++++++- > 3 files changed, 56 insertions(+), 1 deletion(-) > > diff --git a/drivers/input/misc/uinput.c b/drivers/input/misc/uinput.c > index d8ae08d..b51269f 100644 > --- a/drivers/input/misc/uinput.c > +++ b/drivers/input/misc/uinput.c > @@ -20,6 +20,8 @@ > * Author: Aristeu Sergio Rozanski Filho <aris@xxxxxxxxxxxxxxxxx> > * > * Changes/Revisions: > + * 0.4 01/09/2014 (Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx>) > + * - add UI_GET_SYSNAME ioctl > * 0.3 09/04/2006 (Anssi Hannula <anssi.hannula@xxxxxxxxx>) > * - updated ff support for the changes in kernel interface > * - added MODULE_VERSION > @@ -670,6 +672,30 @@ static int uinput_ff_upload_from_user(const char __user *buffer, > __ret; \ > }) > > +static int uinput_str_to_user(void __user *dest, const char *str, > + unsigned int maxlen) > +{ > + int len, ret; > + > + if (!str) > + return -ENOENT; > + > + if (maxlen == 0) > + return -EINVAL; > + > + len = strlen(str) + 1; > + if (len > maxlen) > + len = maxlen; > + > + ret = copy_to_user(dest, str, len); Technically you could use "len - 1" here, but it's fine. Reviewed-by: David Herrmann <dh.herrmann@xxxxxxxxx> Thanks David > + if (ret) > + return -EFAULT; > + > + /* force terminating '\0' */ > + ret = put_user(0, (char *)dest + len - 1); > + return ret ? -EFAULT : len; > +} > + > static long uinput_ioctl_handler(struct file *file, unsigned int cmd, > unsigned long arg, void __user *p) > { > @@ -679,6 +705,8 @@ static long uinput_ioctl_handler(struct file *file, unsigned int cmd, > struct uinput_ff_erase ff_erase; > struct uinput_request *req; > char *phys; > + const char *name; > + unsigned int size; > > retval = mutex_lock_interruptible(&udev->mutex); > if (retval) > @@ -831,6 +859,20 @@ static long uinput_ioctl_handler(struct file *file, unsigned int cmd, > goto out; > } > > + size = _IOC_SIZE(cmd); > + > + /* Now check variable-length commands */ > + switch (cmd & ~IOCSIZE_MASK) { > + case UI_GET_SYSNAME(0): > + if (udev->state != UIST_CREATED) { > + retval = -ENOENT; > + goto out; > + } > + name = dev_name(&udev->dev->dev); > + retval = uinput_str_to_user(p, name, size); > + goto out; > + } > + > retval = -EINVAL; > out: > mutex_unlock(&udev->mutex); > diff --git a/include/linux/uinput.h b/include/linux/uinput.h > index 0a4487d..0994c0d 100644 > --- a/include/linux/uinput.h > +++ b/include/linux/uinput.h > @@ -20,6 +20,8 @@ > * Author: Aristeu Sergio Rozanski Filho <aris@xxxxxxxxxxxxxxxxx> > * > * Changes/Revisions: > + * 0.4 01/09/2014 (Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx>) > + * - add UI_GET_SYSNAME ioctl > * 0.3 24/05/2006 (Anssi Hannula <anssi.hannulagmail.com>) > * - update ff support for the changes in kernel interface > * - add UINPUT_VERSION > diff --git a/include/uapi/linux/uinput.h b/include/uapi/linux/uinput.h > index fe46431..0389b48 100644 > --- a/include/uapi/linux/uinput.h > +++ b/include/uapi/linux/uinput.h > @@ -20,6 +20,8 @@ > * Author: Aristeu Sergio Rozanski Filho <aris@xxxxxxxxxxxxxxxxx> > * > * Changes/Revisions: > + * 0.4 01/09/2014 (Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx>) > + * - add UI_GET_SYSNAME ioctl > * 0.3 24/05/2006 (Anssi Hannula <anssi.hannulagmail.com>) > * - update ff support for the changes in kernel interface > * - add UINPUT_VERSION > @@ -35,7 +37,7 @@ > #include <linux/types.h> > #include <linux/input.h> > > -#define UINPUT_VERSION 3 > +#define UINPUT_VERSION 4 > > > struct uinput_ff_upload { > @@ -73,6 +75,15 @@ struct uinput_ff_erase { > #define UI_BEGIN_FF_ERASE _IOWR(UINPUT_IOCTL_BASE, 202, struct uinput_ff_erase) > #define UI_END_FF_ERASE _IOW(UINPUT_IOCTL_BASE, 203, struct uinput_ff_erase) > > +/** > + * UI_GET_SYSNAME - get the sysfs name of the created uinput device > + * > + * @return the sysfs name of the created virtual input device. > + * The complete sysfs path is then /sys/devices/virtual/input/--NAME-- > + * Usually, it is in the form "inputN" > + */ > +#define UI_GET_SYSNAME(len) _IOC(_IOC_READ, UINPUT_IOCTL_BASE, 300, len) > + > /* > * To write a force-feedback-capable driver, the upload_effect > * and erase_effect callbacks in input_dev must be implemented. > -- > 1.8.4.2 > -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
