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* Copyright © 2013 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 the copyright holders not be used in advertising or
* publicity pertaining to distribution of the software without specific,
* written prior permission. The copyright holders make no representations
* about the suitability of this software for any purpose. It is provided "as
* is" without express or implied warranty.
*
* THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
* INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
* EVENT SHALL THE COPYRIGHT HOLDERS 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.
*/
#ifndef LIBEVDEV_H
#define LIBEVDEV_H
#ifdef __cplusplus
extern "C" {
#endif
#include <linux/input.h>
#include <stdarg.h>
#define LIBEVDEV_ATTRIBUTE_PRINTF(_format, _args) __attribute__ ((format (printf, _format, _args)))
/**
* @mainpage
*
* **libevdev** is a library for handling evdev kernel devices. It abstracts
* the \ref ioctls through type-safe interfaces and provides functions to change
* the appearance of the device.
*
* Development of libevdev is discussed on
* [input-tools@lists.freedesktop.org](http://lists.freedesktop.org/mailman/listinfo/input-tools)
* Please submit patches, questions or general comments there.
*
* Handling events and SYN_DROPPED
* ===============================
*
* libevdev provides an interface for handling events, including most notably
* SYN_DROPPED events. SYN_DROPPED events are sent by the kernel when the
* process does not read events fast enough and the kernel is forced to drop
* some events. This causes the device to get out of sync with the process'
* view of it. libevdev handles this by telling the caller that a SYN_DROPPED
* has been received and that the state of the device is different to what is
* to be expected. It then provides the delta between the previous state and
* the actual state of the device as a set of events. See
* libevdev_next_event() and @ref syn_dropped for more information on how
* SYN_DROPPED is handled.
*
* Signal safety
* =============
*
* libevdev is signal-safe for the majority of its operations, i.e. many of
* its functions are safe to be called from within a signal handler.
* Check the API documentation to make sure, unless explicitly stated a call
* is <b>not</b> signal safe.
*
* Device handling
* ===============
*
* A libevdev context is valid for a given file descriptor and its
* duration. Closing the file descriptor will not destroy the libevdev device
* but libevdev will not be able to read further events.
*
* libevdev does not attempt duplicate detection. Initializing two libevdev
* devices for the same fd is valid and behaves the same as for two different
* devices.
*
* libevdev does not handle the file descriptors directly, it merely uses
* them. The caller is responsible for opening the file descriptors, setting
* them to O_NONBLOCK and handling permissions. A caller should drain any
* events pending on the file descriptor before passing it to libevdev.
*
* Where does libevdev sit?
* ========================
*
* libevdev is essentially a `read(2)` on steroids for `/dev/input/eventX`
* devices. It sits below the process that handles input events, in between
* the kernel and that process. In the simplest case, e.g. an evtest-like tool
* the stack would look like this:
*
* kernel → libevdev → evtest
*
* For X.Org input modules, the stack would look like this:
*
* kernel → libevdev → xf86-input-evdev → X server → X client
*
* For Weston/Wayland, the stack would look like this:
*
* kernel → libevdev → Weston → Wayland client
*
* libevdev does **not** have knowledge of X clients or Wayland clients, it is
* too low in the stack.
*
* Example
* =======
* Below is a simple example that shows how libevdev could be used. This example
* opens a device, checks for relative axes and a left mouse button and if it
* finds them monitors the device to print the event.
*
* @code
* struct libevdev *dev = NULL;
* int fd;
* int rc = 1;
*
* fd = open("/dev/input/event0", O_RDONLY|O_NONBLOCK);
* rc = libevdev_new_from_fd(fd, &dev);
* if (rc < 0) {
* fprintf(stderr, "Failed to init libevdev (%s)\n", strerror(-rc));
* exit(1);
* }
* printf("Input device name: \"%s\"\n", libevdev_get_name(dev));
* printf("Input device ID: bus %#x vendor %#x product %#x\n",
* libevdev_get_id_bustype(dev),
* libevdev_get_id_vendor(dev),
* libevdev_get_id_product(dev));
* if (!libevdev_has_event_type(dev, EV_REL) ||
* !libevdev_has_event_code(dev, EV_KEY, BTN_LEFT)) {
* printf("This device does not look like a mouse\n");
* exit(1);
* }
*
* do {
* struct input_event ev;
* rc = libevdev_next_event(dev, LIBEVDEV_READ_FLAG_NORMAL, &ev);
* if (rc == 0)
* printf("Event: %s %s %d\n",
* libevdev_get_event_type_name(ev.type),
* libevdev_get_event_code_name(ev.type, ev.code),
* ev.value);
* } while (rc == 1 || rc == 0 || rc == -EAGAIN);
* @endcode
*
* A more complete example is available with the libevdev-events tool here:
* http://cgit.freedesktop.org/libevdev/tree/tools/libevdev-events.c
*
* Backwards compatibility with older kernel
* =========================================
* libevdev attempts to build and run correctly on a number of kernel versions.
* If features required are not available, libevdev attempts to work around them
* in the most reasonable way. For more details see \ref backwardscompatibility.
*
* License information
* ===================
* libevdev is licensed under the
* [X11 license](http://cgit.freedesktop.org/libevdev/tree/COPYING).
*
* Reporting bugs
* ==============
* Please report bugs in the freedesktop.org bugzilla under the libevdev product:
* https://bugs.freedesktop.org/enter_bug.cgi?product=libevdev
*/
/**
* @page syn_dropped SYN_DROPPED handling
*
* This page describes how libevdev handles SYN_DROPPED events.
*
* Receiving SYN_DROPPED events
* ============================
*
* The kernel sends evdev events separated by an event of type EV_SYN and
* code SYN_REPORT. Such an event marks the end of a frame of hardware
* events. The number of events between SYN_REPORT events is arbitrary and
* depends on the hardware. An example event sequence may look like this:
* @code
* EV_ABS ABS_X 9
* EV_ABS ABS_Y 8
* EV_SYN SYN_REPORT 0
* ------------------------
* EV_ABS ABS_X 10
* EV_ABS ABS_Y 10
* EV_KEY BTN_TOUCH 1
* EV_SYN SYN_REPORT 0
* ------------------------
* EV_ABS ABS_X 11
* EV_SYN SYN_REPORT 0
* @endcode
*
* Events are handed to the client buffer as they appear, the kernel adjusts
* the buffer size to handle at least one full event. In the normal case,
* the client reads the event and the kernel can place the next event in the
* buffer. If the client is not fast enough, the kernel places an event of
* type EV_SYN and code SYN_DROPPED into the buffer, effectively notifying
* the client that some events were lost. The above example event sequence
* may look like this (note the missing/repeated events):
* @code
* EV_ABS ABS_X 9
* EV_ABS ABS_Y 8
* EV_SYN SYN_REPORT 0
* ------------------------
* EV_ABS ABS_X 10
* EV_ABS ABS_Y 10
* EV_SYN SYN_DROPPED 0
* EV_ABS ABS_Y 15
* EV_SYN SYN_REPORT 0
* ------------------------
* EV_ABS ABS_X 11
* EV_KEY BTN_TOUCH 0
* EV_SYN SYN_REPORT 0
* @endcode
*
* A SYN_DROPPED event may be recieved at any time in the event sequence.
* When a SYN_DROPPED event is received, the client must:
* * discard all events since the last SYN_REPORT
* * discard all events until including the next SYN_REPORT
* These event are part of incomplete event frames.
*
* Synchronizing the state of the device
* =====================================
*
* The handling of the device after a SYN_DROPPED depends on the available
* event codes. For all event codes of type EV_REL, no handling is
* necessary, there is no state attached. For all event codes of type
* EV_KEY, EV_SW, EV_LED and EV_SND, the matching @ref ioctls retrieve the
* current state. The caller must then compare the last-known state to the
* retrieved state and handle the deltas accordingly.
* libevdev simplifies this approach: if the state of the device has
* changed, libevdev generates an event for each code with the new value and
* passes it to the caller during libevdev_next_event() if
* @ref LIBEVDEV_READ_FLAG_SYNC is set.
*
* For events of type EV_ABS and an event code less than ABS_MT_SLOT, the
* handling of state changes is as described above. For events between
* ABS_MT_SLOT and ABS_MAX, the event handling differs.
* Slots are the vehicles to transport information for multiple simultaneous
* touchpoints on a device. Slots are re-used once a touchpoint has ended.
* The kernel sends an ABS_MT_SLOT event whenever the current slot
* changes; any event in the above axis range applies only to the currently
* active slot.
* Thus, an event sequence from a slot-capable device may look like this:
* @code
* EV_ABS ABS_MT_POSITION_Y 10
* EV_ABS ABS_MT_SLOT 1
* EV_ABS ABS_MT_POSITION_X 100
* EV_ABS ABS_MT_POSITION_Y 80
* EV_SYN SYN_REPORT 0
* @endcode
* Note the lack of ABS_MT_SLOT: the first ABS_MT_POSITION_Y applies to
* a slot opened previously, and is the only axis that changed for that
* slot. The touchpoint in slot 1 now has position 100/80.
* The kernel does not provide events if a value does not change, and does
* not send ABS_MT_SLOT events if the slot does not change, or none of the
* values within a slot changes. A client must thus keep the state for each
* slot.
*
* If a SYN_DROPPED is received, the client must sync all slots
* individually and update its internal state. libevdev simplifies this by
* generating multiple events:
* * for each slot on the device, libevdev generates an
* ABS_MT_SLOT event with the value set to the slot number
* * for each event code between ABS_MT_SLOT + 1 and ABS_MAX that changed
* state for this slot, libevdev generates an event for the new state
* * libevdev sends a final ABS_MT_SLOT event for the current slot as
* seen by the kernel
* * libevdev terminates this sequence with an EV_SYN SYN_REPORT event
*
* An example event sequence for such a sync may look like this:
* @code
* EV_ABS ABS_MT_SLOT 0
* EV_ABS ABS_MT_POSITION_Y 10
* EV_ABS ABS_MT_SLOT 1
* EV_ABS ABS_MT_POSITION_X 100
* EV_ABS ABS_MT_POSITION_Y 80
* EV_ABS ABS_MT_SLOT 2
* EV_ABS ABS_MT_POSITION_Y 8
* EV_ABS ABS_MT_PRESSURE 12
* EV_ABS ABS_MT_SLOT 1
* EV_SYN SYN_REPORT 0
* @endcode
* Note the terminating ABS_MT_SLOT event, this indicates that the kernel
* currently has slot 1 active.
*
* Synchronizing ABS_MT_TRACKING_ID
* ================================
*
* The event code ABS_MT_TRACKING_ID is used to denote the start and end of
* a touch point within a slot. An ABS_MT_TRACKING_ID of zero or greater
* denotes the start of a touchpoint, an ABS_MT_TRACKING_ID of -1 denotes
* the end of a touchpoint within this slot. During SYN_DROPPED, a touch
* point may have ended and re-started within a slot - a client must check
* the ABS_MT_TRACKING_ID. libevdev simplifies this by emulating extra
* events if the ABS_MT_TRACKING_ID has changed:
* * if the ABS_MT_TRACKING_ID was valid and is -1, libevdev enqueues an
* ABS_MT_TRACKING_ID event with value -1.
* * if the ABS_MT_TRACKING_ID was -1 and is now a valid ID, libevdev
* enqueues an ABS_MT_TRACKING_ID event with the current value.
* * if the ABS_MT_TRACKING_ID was a valid ID and is now a different valid
* ID, libevev enqueues an ABS_MT_TRACKING_ID event with value -1 and
* another ABS_MT_TRACKING_ID event with the new value.
*
* An example event sequence for such a sync may look like this:
* @code
* EV_ABS ABS_MT_SLOT 0
* EV_ABS ABS_MT_TRACKING_ID -1
* EV_ABS ABS_MT_SLOT 2
* EV_ABS ABS_MT_TRACKING_ID -1
* EV_SYN SYN_REPORT 0
* ------------------------
* EV_ABS ABS_MT_SLOT 1
* EV_ABS ABS_MT_POSITION_X 100
* EV_ABS ABS_MT_POSITION_Y 80
* EV_ABS ABS_MT_SLOT 2
* EV_ABS ABS_MT_TRACKING_ID 45
* EV_ABS ABS_MT_POSITION_Y 8
* EV_ABS ABS_MT_PRESSURE 12
* EV_ABS ABS_MT_SLOT 1
* EV_SYN SYN_REPORT 0
* @endcode
* Note how the touchpoint in slot 0 was terminated, the touchpoint in slot
* 2 was terminated and then started with a new ABS_MT_TRACKING_ID. The touchpoint
* in slot 1 maintained the same ABS_MT_TRACKING_ID and only updated the
* coordinates. Slot 1 is the currently active slot.
*
* In the case of a SYN_DROPPED event, a touch point may be invisible to a
* client if it started after SYN_DROPPED and finished before the client
* handles events again. The below example shows an example event sequence
* and what libevdev sees in the case of a SYN_DROPPED event:
* @code
*
* kernel | userspace
* |
* EV_ABS ABS_MT_SLOT 0 | EV_ABS ABS_MT_SLOT 0
* EV_ABS ABS_MT_TRACKING_ID -1 | EV_ABS ABS_MT_TRACKING_ID -1
* EV_SYN SYN_REPORT 0 | EV_SYN SYN_REPORT 0
* ------------------------ | ------------------------
* EV_ABS ABS_MT_TRACKING_ID 30 |
* EV_ABS ABS_MT_POSITION_X 100 |
* EV_ABS ABS_MT_POSITION_Y 80 |
* EV_SYN SYN_REPORT 0 | SYN_DROPPED
* ------------------------ |
* EV_ABS ABS_MT_TRACKING_ID -1 |
* EV_SYN SYN_REPORT 0 |
* ------------------------ | ------------------------
* EV_ABS ABS_MT_SLOT 1 | EV_ABS ABS_MT_SLOT 1
* EV_ABS ABS_MT_POSITION_X 90 | EV_ABS ABS_MT_POSITION_X 90
* EV_ABS ABS_MT_POSITION_Y 10 | EV_ABS ABS_MT_POSITION_Y 10
* EV_SYN SYN_REPORT 0 | EV_SYN SYN_REPORT 0
* @endcode
* If such an event sequence occurs, libevdev will send all updated axes
* during the sync process. Axis events may thus be generated for devices
* without a currently valid ABS_MT_TRACKING_ID. Specifically for the above
* example, the client would receive the following event sequence:
* @code
* EV_ABS ABS_MT_SLOT 0 ← LIBEVDEV_READ_FLAG_NORMAL
* EV_ABS ABS_MT_TRACKING_ID -1
* EV_SYN SYN_REPORT 0
* ------------------------
* EV_SYN SYN_DROPPED 0 → LIBEVDEV_READ_STATUS_SYNC
* ------------------------
* EV_ABS ABS_MT_POSITION_X 100 ← LIBEVDEV_READ_FLAG_SYNC
* EV_ABS ABS_MT_POSITION_Y 80
* EV_SYN SYN_REPORT 0
* ----------------------------- → -EGAIN
* EV_ABS ABS_MT_SLOT 1 ← LIBEVDEV_READ_FLAG_NORMAL
* EV_ABS ABS_MT_POSITION_X 90
* EV_ABS ABS_MT_POSITION_Y 10
* EV_SYN SYN_REPORT 0
* -------------------
* @endcode
* The axis events do not reflect the position of a current touch point, a
* client must take care not to generate a new touch point based on those
* updates.
*
* Discarding events before synchronizing
* =====================================
*
* The kernel implements the client buffer as a ring buffer. SYN_DROPPED
* events are handled when the buffer is full and a new event is received
* from a device. All existing events are discarded, a SYN_DROPPED is added
* to the buffer followed by the actual device event. Further events will be
* appended to the buffer until it is either read by the client, or filled
* again, at which point the sequence repeats.
*
* When the client reads the buffer, the buffer will thus always consist of
* exactly one SYN_DROPPED event followed by an unspecified number of real
* events. The data the ioctls return is the current state of the device,
* i.e. the state after all these events have been processed. For example,
* assume the buffer contains the following sequence:
*
* @code
* EV_SYN SYN_DROPPED
* EV_ABS ABS_X 1
* EV_SYN SYN_REPORT 0
* EV_ABS ABS_X 2
* EV_SYN SYN_REPORT 0
* EV_ABS ABS_X 3
* EV_SYN SYN_REPORT 0
* EV_ABS ABS_X 4
* EV_SYN SYN_REPORT 0
* EV_ABS ABS_X 5
* EV_SYN SYN_REPORT 0
* EV_ABS ABS_X 6
* EV_SYN SYN_REPORT 0
* @endcode
* An ioctl at any time in this sequence will return a value of 6 for ABS_X.
*
* libevdev discards all events after a SYN_DROPPED to ensure the events
* during @ref LIBEVDEV_READ_FLAG_SYNC represent the last known state of the
* device. This loses some granularity of the events especially as the time
* between the SYN_DROPPED and the sync process increases. It does however
* avoid spurious cursor movements. In the above example, the event sequence
* by libevdev is:
* @code
* EV_SYN SYN_DROPPED
* EV_ABS ABS_X 6
* EV_SYN SYN_REPORT 0
* @endcode
*/
/**
* @page backwardscompatibility Compatibility and Behavior across kernel versions
*
* This page describes libevdev's behavior when the build-time kernel and the
* run-time kernel differ in their feature set.
*
* With the exception of event names, libevdev defines features that may be
* missing on older kernels and building on such kernels will not disable
* features. Running libevdev on a kernel that is missing some feature will
* change libevdev's behavior. In most cases, the new behavior should be
* obvious, but it is spelled out below in detail.
*
* Minimum requirements
* ====================
* libevdev requires a 2.6.36 kernel as minimum. Specifically, it requires
* kernel-support for ABS_MT_SLOT.
*
* Event and input property names
* ==============================
* Event names and input property names are defined at build-time by the
* linux/input.h shipped with libevdev.
* The list of event names is compiled at build-time, any events not defined
* at build time will not resolve. Specifically,
* libevdev_event_code_get_name() for an undefined type or code will
* always return NULL. Likewise, libevdev_property_get_name() will return NULL
* for properties undefined at build-time.
*
* Input properties
* ================
* If the kernel does not support input properties, specifically the
* EVIOCGPROPS ioctl, libevdev does not expose input properties to the caller.
* Specifically, libevdev_has_property() will always return 0 unless the
* property has been manually set with libevdev_enable_property().
*
* This also applies to the libevdev-uinput code. If uinput does not honor
* UI_SET_PROPBIT, libevdev will continue without setting the properties on
* the device.
*
* MT slot behavior
* =================
* If the kernel does not support the EVIOCGMTSLOTS ioctl, libevdev
* assumes all values in all slots are 0 and continues without an error.
*
* SYN_DROPPED behavior
* ====================
* A kernel without SYN_DROPPED won't send such an event. libevdev_next_event()
* will never require the switch to sync mode.
*/
/**
* @page ioctls evdev ioctls
*
* This page lists the status of the evdev-specific ioctls in libevdev.
*
* <dl>
* <dt>EVIOCGVERSION:</dt>
* <dd>supported, see libevdev_get_driver_version()</dd>
* <dt>EVIOCGID:</dt>
* <dd>supported, see libevdev_get_id_product(), libevdev_get_id_vendor(),
* libevdev_get_id_bustype(), libevdev_get_id_version()</dd>
* <dt>EVIOCGREP:</dt>
* <dd>supported, see libevdev_get_event_value())</dd>
* <dt>EVIOCSREP:</dt>
* <dd>supported, see libevdev_enable_event_code()</dd>
* <dt>EVIOCGKEYCODE:</dt>
* <dd>currently not supported</dd>
* <dt>EVIOCGKEYCODE:</dt>
* <dd>currently not supported</dd>
* <dt>EVIOCSKEYCODE:</dt>
* <dd>currently not supported</dd>
* <dt>EVIOCSKEYCODE:</dt>
* <dd>currently not supported</dd>
* <dt>EVIOCGNAME:</dt>
* <dd>supported, see libevdev_get_name()</dd>
* <dt>EVIOCGPHYS:</dt>
* <dd>supported, see libevdev_get_phys()</dd>
* <dt>EVIOCGUNIQ:</dt>
* <dd>supported, see libevdev_get_uniq()</dd>
* <dt>EVIOCGPROP:</dt>
* <dd>supported, see libevdev_has_property()</dd>
* <dt>EVIOCGMTSLOTS:</dt>
* <dd>supported, see libevdev_get_num_slots(), libevdev_get_slot_value()</dd>
* <dt>EVIOCGKEY:</dt>
* <dd>supported, see libevdev_has_event_code(), libevdev_get_event_value()</dd>
* <dt>EVIOCGLED:</dt>
* <dd>supported, see libevdev_has_event_code(), libevdev_get_event_value()</dd>
* <dt>EVIOCGSND:</dt>
* <dd>currently not supported</dd>
* <dt>EVIOCGSW:</dt>
* <dd>supported, see libevdev_has_event_code(), libevdev_get_event_value()</dd>
* <dt>EVIOCGBIT:</dt>
* <dd>supported, see libevdev_has_event_code(), libevdev_get_event_value()</dd>
* <dt>EVIOCGABS:</dt>
* <dd>supported, see libevdev_has_event_code(), libevdev_get_event_value(),
* libevdev_get_abs_info()</dd>
* <dt>EVIOCSABS:</dt>
* <dd>supported, see libevdev_kernel_set_abs_info()</dd>
* <dt>EVIOCSFF:</dt>
* <dd>currently not supported</dd>
* <dt>EVIOCRMFF:</dt>
* <dd>currently not supported</dd>
* <dt>EVIOCGEFFECTS:</dt>
* <dd>currently not supported</dd>
* <dt>EVIOCGRAB:</dt>
* <dd>supported, see libevdev_grab()</dd>
* <dt>EVIOCSCLOCKID:</dt>
* <dd>supported, see libevdev_set_clock_id()</dd>
* <dt>EVIOCREVOKE:</dt>
* <dd>currently not supported, see
* http://lists.freedesktop.org/archives/input-tools/2014-January/000688.html</dd>
* </dl>
*
*/
/**
* @page kernel_header Kernel header
*
* libevdev provides its own copy of the Linux kernel header file and
* compiles against the definitions define here. Event type and event code
* names, etc. are taken from the file below:
* @include linux/input.h
*/
/**
* @page static_linking Statically linking libevdev
*
* Statically linking libevdev.a is not recommended. Symbol visibility is
* difficult to control in a static library, so extra care must be taken to
* only use symbols that are explicitly exported. libevdev's API stability
* guarantee only applies to those symbols.
*
* If you do link libevdev statically, note that in addition to the exported
* symbols, libevdev reserves the <b>_libevdev_*</b> namespace. Do not use
* or create symbols with that prefix, they are subject to change at any
* time.
*/
/**
* @page testing libevdev-internal test suite
*
* libevdev's internal test suite uses the
* [Check unit testing framework](http://check.sourceforge.net/). Tests are
* divided into test suites and test cases. Most tests create a uinput device,
* so you'll need to run as root, and your kernel must have
* CONFIG_INPUT_UINPUT enabled.
*
* To run a specific suite only:
*
* export CK_RUN_SUITE="suite name"
*
* To run a specific test case only:
*
* export CK_RUN_TEST="test case name"
*
* To get a list of all suites or tests:
*
* git grep "suite_create"
* git grep "tcase_create"
*
* By default, Check forks, making debugging harder. The test suite tries to detect
* if it is running inside gdb and disable forking. If that doesn't work for
* some reason, run gdb as below to avoid forking.
*
* sudo CK_FORK=no CK_RUN_TEST="test case name" gdb ./test/test-libevdev
*
* A special target `make gcov-report.txt` exists that runs gcov and leaves a
* `libevdev.c.gcov` file. Check that for test coverage.
*
* `make check` is hooked up to run the test and gcov (again, needs root).
*
* The test suite creates a lot of devices, very quickly. Add the following
* xorg.conf.d snippet to avoid the devices being added as X devices (at the
* time of writing, mutter can't handle these devices and exits after getting
* a BadDevice error).
*
* $ cat /etc/X11/xorg.conf.d/99-ignore-libevdev-devices.conf
* Section "InputClass"
* Identifier "Ignore libevdev test devices"
* MatchProduct "libevdev test device"
* Option "Ignore" "on"
* EndSection
*
*/
/**
* @defgroup init Initialization and setup
*
* Initialization, initial setup and file descriptor handling.
* These functions are the main entry points for users of libevdev, usually a
* caller will use this series of calls:
*
* @code
* struct libevdev *dev;
* int err;
*
* dev = libevdev_new();
* if (!dev)
* return ENOMEM;
*
* err = libevdev_set_fd(dev, fd);
* if (err < 0) {
* printf("Failed (errno %d): %s\n", -err, strerror(-err));
*
* libevdev_free(dev);
* @endcode
*
* libevdev_set_fd() is the central call and initializes the internal structs
* for the device at the given fd. libevdev functions will fail if called
* before libevdev_set_fd() unless documented otherwise.
*/
/**
* @defgroup logging Library logging facilities
*
* libevdev provides two methods of logging library-internal messages. The
* old method is to provide a global log handler in
* libevdev_set_log_function(). The new method is to provide a per-context
* log handler in libevdev_set_device_log_function(). Developers are encouraged
* to use the per-context logging facilities over the global log handler as
* it provides access to the libevdev instance that caused a message, and is
* more flexible when libevdev is used from within a shared library.
*
* If a caller sets both the global log handler and a per-context log
* handler, each device with a per-context log handler will only invoke that
* log handler.
*
* @note To set a context-specific log handler, a context is needed.
* Thus developers are discouraged from using libevdev_new_from_fd() as
* important messages from the device initialization process may get lost.
*
* @note A context-specific handler cannot be used for libevdev's uinput
* devices. @ref uinput must use the global log handler.
*/
/**
* @defgroup bits Querying device capabilities
*
* Abstraction functions to handle device capabilities, specificially
* device properties such as the name of the device and the bits
* representing the events suppported by this device.
*
* The logical state returned may lag behind the physical state of the device.
* libevdev queries the device state on libevdev_set_fd() and then relies on
* the caller to parse events through libevdev_next_event(). If a caller does not
* use libevdev_next_event(), libevdev will not update the internal state of the
* device and thus returns outdated values.
*/
/**
* @defgroup mt Multi-touch related functions
* Functions for querying multi-touch-related capabilities. MT devices
* following the kernel protocol B (using ABS_MT_SLOT) provide multiple touch
* points through so-called slots on the same axis. The slots are enumerated,
* a client reading from the device will first get an ABS_MT_SLOT event, then
* the values of axes changed in this slot. Multiple slots may be provided in
* before an EV_SYN event.
*
* As with @ref bits, the logical state of the device as seen by the library
* depends on the caller using libevdev_next_event().
*
* The Linux kernel requires all axes on a device to have a semantic
* meaning, matching the axis names in linux/input.h. Some devices merely
* export a number of axes beyond the available axis list. For those
* devices, the multitouch information is invalid. Specfically, if a device
* provides the ABS_MT_SLOT axis AND also the (ABS_MT_SLOT - 1) axis, the
* device is not treated as multitouch device. No slot information is
* available and the ABS_MT axis range for these devices is treated as all
* other EV_ABS axes.
*
* Note that because of limitations in the kernel API, such fake multitouch
* devices can not be reliably synched after a SYN_DROPPED event. libevdev
* ignores all ABS_MT axis values during the sync process and instead
* relies on the device to send the current axis value with the first event
* after SYN_DROPPED.
*/
/**
* @defgroup kernel Modifying the appearance or capabilities of the device
*
* Modifying the set of events reported by this device. By default, the
* libevdev device mirrors the kernel device, enabling only those bits
* exported by the kernel. This set of functions enable or disable bits as
* seen from the caller.
*
* Enabling an event type or code does not affect event reporting - a
* software-enabled event will not be generated by the physical hardware.
* Disabling an event will prevent libevdev from routing such events to the
* caller. Enabling and disabling event types and codes is at the library
* level and thus only affects the caller.
*
* If an event type or code is enabled at kernel-level, future users of this
* device will see this event enabled. Currently there is no option of
* disabling an event type or code at kernel-level.
*/
/**
* @defgroup misc Miscellaneous helper functions
*
* Functions for printing or querying event ranges. The list of names is
* compiled into libevdev and is independent of the run-time kernel.
* Likewise, the max for each event type is compiled in and does not check
* the kernel at run-time.
*/
/**
* @defgroup events Event handling
*
* Functions to handle events and fetch the current state of the event.
* libevdev updates its internal state as the event is processed and forwarded
* to the caller. Thus, the libevdev state of the device should always be identical
* to the caller's state. It may however lag behind the actual state of the device.
*/
/**
* @ingroup init
*
* Opaque struct representing an evdev device.
*/
struct libevdev;
/**
* @ingroup events
*/
enum libevdev_read_flag {
LIBEVDEV_READ_FLAG_SYNC = 1, /**< Process data in sync mode */
LIBEVDEV_READ_FLAG_NORMAL = 2, /**< Process data in normal mode */
LIBEVDEV_READ_FLAG_FORCE_SYNC = 4, /**< Pretend the next event is a SYN_DROPPED and
require the caller to sync */
LIBEVDEV_READ_FLAG_BLOCKING = 8 /**< The fd is not in O_NONBLOCK and a read may block */
};
/**
* @ingroup init
*
* Initialize a new libevdev device. This function only allocates the
* required memory and initializes the struct to sane default values.
* To actually hook up the device to a kernel device, use
* libevdev_set_fd().
*
* Memory allocated through libevdev_new() must be released by the
* caller with libevdev_free().
*
* @see libevdev_set_fd
* @see libevdev_free
*/
struct libevdev* libevdev_new(void);
/**
* @ingroup init
*
* Initialize a new libevdev device from the given fd.
*
* This is a shortcut for
*
* @code
* int err;
* struct libevdev *dev = libevdev_new();
* err = libevdev_set_fd(dev, fd);
* @endcode
*
* @param fd A file descriptor to the device in O_RDWR or O_RDONLY mode.
* @param[out] dev The newly initialized evdev device.
*
* @return On success, 0 is returned and dev is set to the newly
* allocated struct. On failure, a negative errno is returned and the value
* of dev is undefined.
*
* @see libevdev_free
*/
int libevdev_new_from_fd(int fd, struct libevdev **dev);
/**
* @ingroup init
*
* Clean up and free the libevdev struct. After completion, the <code>struct
* libevdev</code> is invalid and must not be used.
*
* Note that calling libevdev_free() does not close the file descriptor
* currently asssociated with this instance.
*
* @param dev The evdev device
*
* @note This function may be called before libevdev_set_fd().
*/
void libevdev_free(struct libevdev *dev);
/**
* @ingroup logging
*/
enum libevdev_log_priority {
LIBEVDEV_LOG_ERROR = 10, /**< critical errors and application bugs */
LIBEVDEV_LOG_INFO = 20, /**< informational messages */
LIBEVDEV_LOG_DEBUG = 30 /**< debug information */
};
/**
* @ingroup logging
*
* Logging function called by library-internal logging.
* This function is expected to treat its input like printf would.
*
* @param priority Log priority of this message
* @param data User-supplied data pointer (see libevdev_set_log_function())
* @param file libevdev source code file generating this message
* @param line libevdev source code line generating this message
* @param func libevdev source code function generating this message
* @param format printf-style format string
* @param args List of arguments
*
* @see libevdev_set_log_function
*/
typedef void (*libevdev_log_func_t)(enum libevdev_log_priority priority,
void *data,
const char *file, int line,
const char *func,
const char *format, va_list args)
LIBEVDEV_ATTRIBUTE_PRINTF(6, 0);
/**
* @ingroup logging
*
* Set a printf-style logging handler for library-internal logging. The default
* logging function is to stdout.
*
* @note The global log handler is only called if no context-specific log
* handler has been set with libevdev_set_device_log_function().
*
* @param logfunc The logging function for this device. If NULL, the current
* logging function is unset and no logging is performed.
* @param data User-specific data passed to the log handler.
*
* @note This function may be called before libevdev_set_fd().
*
* @deprecated Use per-context logging instead, see
* libevdev_set_device_log_function().
*/
void libevdev_set_log_function(libevdev_log_func_t logfunc, void *data);
/**
* @ingroup logging
*
* Define the minimum level to be printed to the log handler.
* Messages higher than this level are printed, others are discarded. This
* is a global setting and applies to any future logging messages.
*
* @param priority Minimum priority to be printed to the log.
*
* @deprecated Use per-context logging instead, see
* libevdev_set_device_log_function().
*/
void libevdev_set_log_priority(enum libevdev_log_priority priority);
/**
* @ingroup logging
*
* Return the current log priority level. Messages higher than this level
* are printed, others are discarded. This is a global setting.
*
* @return the current log level
*
* @deprecated Use per-context logging instead, see
* libevdev_set_device_log_function().
*/
enum libevdev_log_priority libevdev_get_log_priority(void);
/**
* @ingroup logging
*
* Logging function called by library-internal logging for a specific
* libevdev context. This function is expected to treat its input like
* printf would.
*
* @param dev The evdev device
* @param priority Log priority of this message
* @param data User-supplied data pointer (see libevdev_set_log_function())
* @param file libevdev source code file generating this message
* @param line libevdev source code line generating this message
* @param func libevdev source code function generating this message
* @param format printf-style format string
* @param args List of arguments
*
* @see libevdev_set_log_function
* @since 1.3
*/
typedef void (*libevdev_device_log_func_t)(const struct libevdev *dev,
enum libevdev_log_priority priority,
void *data,
const char *file, int line,
const char *func,
const char *format, va_list args)
LIBEVDEV_ATTRIBUTE_PRINTF(7, 0);
/**
* @ingroup logging
*
* Set a printf-style logging handler for library-internal logging for this
* device context. The default logging function is NULL, i.e. the global log
* handler is invoked. If a context-specific log handler is set, the global
* log handler is not invoked for this device.
*
* @note This log function applies for this device context only, even if
* another context exists for the same fd.
*
* @param dev The evdev device
* @param logfunc The logging function for this device. If NULL, the current
* logging function is unset and logging falls back to the global log
* handler, if any.
* @param priority Minimum priority to be printed to the log.
* @param data User-specific data passed to the log handler.
*
* @note This function may be called before libevdev_set_fd().
* @since 1.3
*/
void libevdev_set_device_log_function(struct libevdev *dev,
libevdev_device_log_func_t logfunc,
enum libevdev_log_priority priority,
void *data);
/**
* @ingroup init
*/
enum libevdev_grab_mode {
LIBEVDEV_GRAB = 3, /**< Grab the device if not currently grabbed */
LIBEVDEV_UNGRAB = 4 /**< Ungrab the device if currently grabbed */
};
/**
* @ingroup init
*
* Grab or ungrab the device through a kernel EVIOCGRAB. This prevents other
* clients (including kernel-internal ones such as rfkill) from receiving
* events from this device.
*
* This is generally a bad idea. Don't do this.
*
* Grabbing an already grabbed device, or ungrabbing an ungrabbed device is
* a noop and always succeeds.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param grab If true, grab the device. Otherwise ungrab the device.
*
* @return 0 if the device was successfull grabbed or ungrabbed, or a
* negative errno in case of failure.
*/
int libevdev_grab(struct libevdev *dev, enum libevdev_grab_mode grab);
/**
* @ingroup init
*
* Set the fd for this struct and initialize internal data.
* The fd must be in O_RDONLY or O_RDWR mode.
*
* This function may only be called once per device. If the device changed and
* you need to re-read a device, use libevdev_free() and libevdev_new(). If
* you need to change the fd after closing and re-opening the same device, use
* libevdev_change_fd().
*
* A caller should ensure that any events currently pending on the fd are
* drained before the file descriptor is passed to libevdev for
* initialization. Due to how the kernel's ioctl handling works, the initial
* device state will reflect the current device state *after* applying all
* events currently pending on the fd. Thus, if the fd is not drained, the
* state visible to the caller will be inconsistent with the events
* immediately available on the device. This does not affect state-less
* events like EV_REL.
*
* Unless otherwise specified, libevdev function behavior is undefined until
* a successfull call to libevdev_set_fd().
*
* @param dev The evdev device
* @param fd The file descriptor for the device
*
* @return 0 on success, or a negative errno on failure
*
* @see libevdev_change_fd
* @see libevdev_new
* @see libevdev_free
*/
int libevdev_set_fd(struct libevdev* dev, int fd);
/**
* @ingroup init
*
* Change the fd for this device, without re-reading the actual device. If the fd
* changes after initializing the device, for example after a VT-switch in the
* X.org X server, this function updates the internal fd to the newly opened.
* No check is made that new fd points to the same device. If the device has
* changed, libevdev's behavior is undefined.
*
* libevdev does not sync itself after changing the fd and keeps the current
* device state. Use libevdev_next_event with the
* @ref LIBEVDEV_READ_FLAG_FORCE_SYNC flag to force a re-sync.
*
* The example code below illustrates how to force a re-sync of the
* library-internal state. Note that this code doesn't handle the events in
* the caller, it merely forces an update of the internal library state.
* @code
* struct input_event ev;
* libevdev_change_fd(dev, new_fd);
* libevdev_next_event(dev, LIBEVDEV_READ_FLAG_FORCE_SYNC, &ev);
* while (libevdev_next_event(dev, LIBEVDEV_READ_FLAG_SYNC, &ev) == LIBEVDEV_READ_STATUS_SYNC)
* ; // noop
* @endcode
*
* The fd may be open in O_RDONLY or O_RDWR.
*
* It is an error to call this function before calling libevdev_set_fd().
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param fd The new fd
*
* @return 0 on success, or -1 on failure.
*
* @see libevdev_set_fd
*/
int libevdev_change_fd(struct libevdev* dev, int fd);
/**
* @ingroup init
*
* @param dev The evdev device
*
* @return The previously set fd, or -1 if none had been set previously.
* @note This function may be called before libevdev_set_fd().
*/
int libevdev_get_fd(const struct libevdev* dev);
/**
* @ingroup events
*/
enum libevdev_read_status {
/**
* libevdev_next_event() has finished without an error
* and an event is available for processing.
*
* @see libevdev_next_event
*/
LIBEVDEV_READ_STATUS_SUCCESS = 0,
/**
* Depending on the libevdev_next_event() read flag:
* * libevdev received a SYN_DROPPED from the device, and the caller should
* now resync the device, or,
* * an event has been read in sync mode.
*
* @see libevdev_next_event
*/
LIBEVDEV_READ_STATUS_SYNC = 1
};
/**
* @ingroup events
*
* Get the next event from the device. This function operates in two different
* modes: normal mode or sync mode.
*
* In normal mode (when flags has @ref LIBEVDEV_READ_FLAG_NORMAL set), this
* function returns @ref LIBEVDEV_READ_STATUS_SUCCESS and returns the event
* in the argument @p ev. If no events are available at this
* time, it returns -EAGAIN and ev is undefined.
*
* If the current event is an EV_SYN SYN_DROPPED event, this function returns
* @ref LIBEVDEV_READ_STATUS_SYNC and ev is set to the EV_SYN event.
* The caller should now call this function with the
* @ref LIBEVDEV_READ_FLAG_SYNC flag set, to get the set of events that make up the
* device state delta. This function returns @ref LIBEVDEV_READ_STATUS_SYNC for
* each event part of that delta, until it returns -EAGAIN once all events
* have been synced. For more details on what libevdev does to sync after a
* SYN_DROPPED event, see @ref syn_dropped.
*
* If a device needs to be synced by the caller but the caller does not call
* with the @ref LIBEVDEV_READ_FLAG_SYNC flag set, all events from the diff are
* dropped after libevdev updates its internal state and event processing
* continues as normal. Note that the current slot and the state of touch
* points may have updated during the SYN_DROPPED event, it is strongly
* recommended that a caller ignoring all sync events calls
* libevdev_get_current_slot() and checks the ABS_MT_TRACKING_ID values for
* all slots.
*
* If a device has changed state without events being enqueued in libevdev,
* e.g. after changing the file descriptor, use the @ref
* LIBEVDEV_READ_FLAG_FORCE_SYNC flag. This triggers an internal sync of the
* device and libevdev_next_event() returns @ref LIBEVDEV_READ_STATUS_SYNC.
* Any state changes are available as events as described above. If
* @ref LIBEVDEV_READ_FLAG_FORCE_SYNC is set, the value of ev is undefined.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param flags Set of flags to determine behaviour. If @ref LIBEVDEV_READ_FLAG_NORMAL
* is set, the next event is read in normal mode. If @ref LIBEVDEV_READ_FLAG_SYNC is
* set, the next event is read in sync mode.
* @param ev On success, set to the current event.
* @return On failure, a negative errno is returned.
* @retval LIBEVDEV_READ_STATUS_SUCCESS One or more events were read of the
* device and ev points to the next event in the queue
* @retval -EAGAIN No events are currently available on the device
* @retval LIBEVDEV_READ_STATUS_SYNC A SYN_DROPPED event was received, or a
* synced event was returned and ev points to the SYN_DROPPED event
*
* @note This function is signal-safe.
*/
int libevdev_next_event(struct libevdev *dev, unsigned int flags, struct input_event *ev);
/**
* @ingroup events
*
* Check if there are events waiting for us. This function does not read an
* event off the fd and may not access the fd at all. If there are events
* queued internally this function will return non-zero. If the internal
* queue is empty, this function will poll the file descriptor for data.
*
* This is a convenience function for simple processes, most complex programs
* are expected to use select(2) or poll(2) on the file descriptor. The kernel
* guarantees that if data is available, it is a multiple of sizeof(struct
* input_event), and thus calling libevdev_next_event() when select(2) or
* poll(2) return is safe. You do not need libevdev_has_event_pending() if
* you're using select(2) or poll(2).
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @return On failure, a negative errno is returned.
* @retval 0 No event is currently available
* @retval 1 One or more events are available on the fd
*
* @note This function is signal-safe.
*/
int libevdev_has_event_pending(struct libevdev *dev);
/**
* @ingroup bits
*
* Retrieve the device's name, either as set by the caller or as read from
* the kernel. The string returned is valid until libevdev_free() or until
* libevdev_set_name(), whichever comes earlier.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
*
* @return The device name as read off the kernel device. The name is never
* NULL but it may be the empty string.
*
* @note This function is signal-safe.
*/
const char* libevdev_get_name(const struct libevdev *dev);
/**
* @ingroup kernel
*
* Change the device's name as returned by libevdev_get_name(). This
* function destroys the string previously returned by libevdev_get_name(),
* a caller must take care that no references are kept.
*
* @param dev The evdev device
* @param name The new, non-NULL, name to assign to this device.
*
* @note This function may be called before libevdev_set_fd(). A call to
* libevdev_set_fd() will overwrite any previously set value.
*/
void libevdev_set_name(struct libevdev *dev, const char *name);
/**
* @ingroup bits
*
* Retrieve the device's physical location, either as set by the caller or
* as read from the kernel. The string returned is valid until
* libevdev_free() or until libevdev_set_phys(), whichever comes earlier.
*
* Virtual devices such as uinput devices have no phys location.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
*
* @return The physical location of this device, or NULL if there is none
*
* @note This function is signal safe.
*/
const char * libevdev_get_phys(const struct libevdev *dev);
/**
* @ingroup kernel
*
* Change the device's physical location as returned by libevdev_get_phys().
* This function destroys the string previously returned by
* libevdev_get_phys(), a caller must take care that no references are kept.
*
* @param dev The evdev device
* @param phys The new phys to assign to this device.
*
* @note This function may be called before libevdev_set_fd(). A call to
* libevdev_set_fd() will overwrite any previously set value.
*/
void libevdev_set_phys(struct libevdev *dev, const char *phys);
/**
* @ingroup bits
*
* Retrieve the device's unique identifier, either as set by the caller or
* as read from the kernel. The string returned is valid until
* libevdev_free() or until libevdev_set_uniq(), whichever comes earlier.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
*
* @return The unique identifier for this device, or NULL if there is none
*
* @note This function is signal safe.
*/
const char * libevdev_get_uniq(const struct libevdev *dev);
/**
* @ingroup kernel
*
* Change the device's unique identifier as returned by libevdev_get_uniq().
* This function destroys the string previously returned by
* libevdev_get_uniq(), a caller must take care that no references are kept.
*
* @param dev The evdev device
* @param uniq The new uniq to assign to this device.
*
* @note This function may be called before libevdev_set_fd(). A call to
* libevdev_set_fd() will overwrite any previously set value.
*/
void libevdev_set_uniq(struct libevdev *dev, const char *uniq);
/**
* @ingroup bits
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
*
* @return The device's product ID
*
* @note This function is signal-safe.
*/
int libevdev_get_id_product(const struct libevdev *dev);
/**
* @ingroup kernel
*
* @param dev The evdev device
* @param product_id The product ID to assign to this device
*
* @note This function may be called before libevdev_set_fd(). A call to
* libevdev_set_fd() will overwrite any previously set value.
*/
void libevdev_set_id_product(struct libevdev *dev, int product_id);
/**
* @ingroup bits
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
*
* @return The device's vendor ID
*
* @note This function is signal-safe.
*/
int libevdev_get_id_vendor(const struct libevdev *dev);
/**
* @ingroup kernel
*
* @param dev The evdev device
* @param vendor_id The vendor ID to assign to this device
*
* @note This function may be called before libevdev_set_fd(). A call to
* libevdev_set_fd() will overwrite any previously set value.
*/
void libevdev_set_id_vendor(struct libevdev *dev, int vendor_id);
/**
* @ingroup bits
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
*
* @return The device's bus type
*
* @note This function is signal-safe.
*/
int libevdev_get_id_bustype(const struct libevdev *dev);
/**
* @ingroup kernel
*
* @param dev The evdev device
* @param bustype The bustype to assign to this device
*
* @note This function may be called before libevdev_set_fd(). A call to
* libevdev_set_fd() will overwrite any previously set value.
*/
void libevdev_set_id_bustype(struct libevdev *dev, int bustype);
/**
* @ingroup bits
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
*
* @return The device's firmware version
*
* @note This function is signal-safe.
*/
int libevdev_get_id_version(const struct libevdev *dev);
/**
* @ingroup kernel
*
* @param dev The evdev device
* @param version The version to assign to this device
*
* @note This function may be called before libevdev_set_fd(). A call to
* libevdev_set_fd() will overwrite any previously set value.
*/
void libevdev_set_id_version(struct libevdev *dev, int version);
/**
* @ingroup bits
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
*
* @return The driver version for this device
*
* @note This function is signal-safe.
*/
int libevdev_get_driver_version(const struct libevdev *dev);
/**
* @ingroup bits
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param prop The input property to query for, one of INPUT_PROP_...
*
* @return 1 if the device provides this input property, or 0 otherwise.
*
* @note This function is signal-safe
*/
int libevdev_has_property(const struct libevdev *dev, unsigned int prop);
/**
* @ingroup kernel
*
* @param dev The evdev device
* @param prop The input property to enable, one of INPUT_PROP_...
*
* @return 0 on success or -1 on failure
*
* @note This function may be called before libevdev_set_fd(). A call to
* libevdev_set_fd() will overwrite any previously set value.
*/
int libevdev_enable_property(struct libevdev *dev, unsigned int prop);
/**
* @ingroup bits
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param type The event type to query for, one of EV_SYN, EV_REL, etc.
*
* @return 1 if the device supports this event type, or 0 otherwise.
*
* @note This function is signal-safe.
*/
int libevdev_has_event_type(const struct libevdev *dev, unsigned int type);
/**
* @ingroup bits
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param type The event type for the code to query (EV_SYN, EV_REL, etc.)
* @param code The event code to query for, one of ABS_X, REL_X, etc.
*
* @return 1 if the device supports this event type and code, or 0 otherwise.
*
* @note This function is signal-safe.
*/
int libevdev_has_event_code(const struct libevdev *dev, unsigned int type, unsigned int code);
/**
* @ingroup bits
*
* Get the minimum axis value for the given axis, as advertised by the kernel.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param code The EV_ABS event code to query for, one of ABS_X, ABS_Y, etc.
*
* @return axis minimum for the given axis or 0 if the axis is invalid
*
* @note This function is signal-safe.
*/
int libevdev_get_abs_minimum(const struct libevdev *dev, unsigned int code);
/**
* @ingroup bits
*
* Get the maximum axis value for the given axis, as advertised by the kernel.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param code The EV_ABS event code to query for, one of ABS_X, ABS_Y, etc.
*
* @return axis maximum for the given axis or 0 if the axis is invalid
*
* @note This function is signal-safe.
*/
int libevdev_get_abs_maximum(const struct libevdev *dev, unsigned int code);
/**
* @ingroup bits
*
* Get the axis fuzz for the given axis, as advertised by the kernel.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param code The EV_ABS event code to query for, one of ABS_X, ABS_Y, etc.
*
* @return axis fuzz for the given axis or 0 if the axis is invalid
*
* @note This function is signal-safe.
*/
int libevdev_get_abs_fuzz(const struct libevdev *dev, unsigned int code);
/**
* @ingroup bits
*
* Get the axis flat for the given axis, as advertised by the kernel.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param code The EV_ABS event code to query for, one of ABS_X, ABS_Y, etc.
*
* @return axis flat for the given axis or 0 if the axis is invalid
*
* @note This function is signal-safe.
*/
int libevdev_get_abs_flat(const struct libevdev *dev, unsigned int code);
/**
* @ingroup bits
*
* Get the axis resolution for the given axis, as advertised by the kernel.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param code The EV_ABS event code to query for, one of ABS_X, ABS_Y, etc.
*
* @return axis resolution for the given axis or 0 if the axis is invalid
*
* @note This function is signal-safe.
*/
int libevdev_get_abs_resolution(const struct libevdev *dev, unsigned int code);
/**
* @ingroup bits
*
* Get the axis info for the given axis, as advertised by the kernel.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param code The EV_ABS event code to query for, one of ABS_X, ABS_Y, etc.
*
* @return The input_absinfo for the given code, or NULL if the device does
* not support this event code.
*
* @note This function is signal-safe.
*/
const struct input_absinfo* libevdev_get_abs_info(const struct libevdev *dev, unsigned int code);
/**
* @ingroup bits
*
* Behaviour of this function is undefined if the device does not provide
* the event.
*
* If the device supports ABS_MT_SLOT, the value returned for any ABS_MT_*
* event code is the value of the currently active slot. You should use
* libevdev_get_slot_value() instead.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param type The event type for the code to query (EV_SYN, EV_REL, etc.)
* @param code The event code to query for, one of ABS_X, REL_X, etc.
*
* @return The current value of the event.
*
* @note This function is signal-safe.
* @note The value for ABS_MT_ events is undefined, use
* libevdev_get_slot_value() instead
*
* @see libevdev_get_slot_value
*/
int libevdev_get_event_value(const struct libevdev *dev, unsigned int type, unsigned int code);
/**
* @ingroup kernel
*
* Set the value for a given event type and code. This only makes sense for
* some event types, e.g. setting the value for EV_REL is pointless.
*
* This is a local modification only affecting only this representation of
* this device. A future call to libevdev_get_event_value() will return this
* value, unless the value was overwritten by an event.
*
* If the device supports ABS_MT_SLOT, the value set for any ABS_MT_*
* event code is the value of the currently active slot. You should use
* libevdev_set_slot_value() instead.
*
* If the device supports ABS_MT_SLOT and the type is EV_ABS and the code is
* ABS_MT_SLOT, the value must be a positive number less then the number of
* slots on the device. Otherwise, libevdev_set_event_value() returns -1.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param type The event type for the code to query (EV_SYN, EV_REL, etc.)
* @param code The event code to set the value for, one of ABS_X, LED_NUML, etc.
* @param value The new value to set
*
* @return 0 on success, or -1 on failure.
* @retval -1 the device does not have the event type or code enabled, or the code is outside the
* allowed limits for the given type, or the type cannot be set, or the
* value is not permitted for the given code.
*
* @see libevdev_set_slot_value
* @see libevdev_get_event_value
*/
int libevdev_set_event_value(struct libevdev *dev, unsigned int type, unsigned int code, int value);
/**
* @ingroup bits
*
* Fetch the current value of the event type. This is a shortcut for
*
* @code
* if (libevdev_has_event_type(dev, t) && libevdev_has_event_code(dev, t, c))
* val = libevdev_get_event_value(dev, t, c);
* @endcode
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param type The event type for the code to query (EV_SYN, EV_REL, etc.)
* @param code The event code to query for, one of ABS_X, REL_X, etc.
* @param[out] value The current value of this axis returned.
*
* @return If the device supports this event type and code, the return value is
* non-zero and value is set to the current value of this axis. Otherwise,
* 0 is returned and value is unmodified.
*
* @note This function is signal-safe.
* @note The value for ABS_MT_ events is undefined, use
* libevdev_fetch_slot_value() instead
*
* @see libevdev_fetch_slot_value
*/
int libevdev_fetch_event_value(const struct libevdev *dev, unsigned int type, unsigned int code, int *value);
/**
* @ingroup mt
*
* Return the current value of the code for the given slot.
*
* The return value is undefined for a slot exceeding the available slots on
* the device, for a code that is not in the permitted ABS_MT range or for a
* device that does not have slots.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param slot The numerical slot number, must be smaller than the total number
* of slots on this device
* @param code The event code to query for, one of ABS_MT_POSITION_X, etc.
*
* @note This function is signal-safe.
* @note The value for events other than ABS_MT_ is undefined, use
* libevdev_fetch_value() instead
*
* @see libevdev_get_event_value
*/
int libevdev_get_slot_value(const struct libevdev *dev, unsigned int slot, unsigned int code);
/**
* @ingroup kernel
*
* Set the value for a given code for the given slot.
*
* This is a local modification only affecting only this representation of
* this device. A future call to libevdev_get_slot_value() will return this
* value, unless the value was overwritten by an event.
*
* This function does not set event values for axes outside the ABS_MT range,
* use libevdev_set_event_value() instead.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param slot The numerical slot number, must be smaller than the total number
* of slots on this device
* @param code The event code to set the value for, one of ABS_MT_POSITION_X, etc.
* @param value The new value to set
*
* @return 0 on success, or -1 on failure.
* @retval -1 the device does not have the event code enabled, or the code is
* outside the allowed limits for multitouch events, or the slot number is outside
* the limits for this device, or the device does not support multitouch events.
*
* @see libevdev_set_event_value
* @see libevdev_get_slot_value
*/
int libevdev_set_slot_value(struct libevdev *dev, unsigned int slot, unsigned int code, int value);
/**
* @ingroup mt
*
* Fetch the current value of the code for the given slot. This is a shortcut for
*
* @code
* if (libevdev_has_event_type(dev, EV_ABS) &&
* libevdev_has_event_code(dev, EV_ABS, c) &&
* slot < device->number_of_slots)
* val = libevdev_get_slot_value(dev, slot, c);
* @endcode
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param slot The numerical slot number, must be smaller than the total number
* of slots on this * device
* @param[out] value The current value of this axis returned.
*
* @param code The event code to query for, one of ABS_MT_POSITION_X, etc.
* @return If the device supports this event code, the return value is
* non-zero and value is set to the current value of this axis. Otherwise, or
* if the event code is not an ABS_MT_* event code, 0 is returned and value
* is unmodified.
*
* @note This function is signal-safe.
*/
int libevdev_fetch_slot_value(const struct libevdev *dev, unsigned int slot, unsigned int code, int *value);
/**
* @ingroup mt
*
* Get the number of slots supported by this device.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
*
* @return The number of slots supported, or -1 if the device does not provide
* any slots
*
* @note A device may provide ABS_MT_SLOT but a total number of 0 slots. Hence
* the return value of -1 for "device does not provide slots at all"
*/
int libevdev_get_num_slots(const struct libevdev *dev);
/**
* @ingroup mt
*
* Get the currently active slot. This may differ from the value
* an ioctl may return at this time as events may have been read off the fd
* since changing the slot value but those events are still in the buffer
* waiting to be processed. The returned value is the value a caller would
* see if it were to process events manually one-by-one.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
*
* @return the currently active slot (logically)
*
* @note This function is signal-safe.
*/
int libevdev_get_current_slot(const struct libevdev *dev);
/**
* @ingroup kernel
*
* Change the minimum for the given EV_ABS event code, if the code exists.
* This function has no effect if libevdev_has_event_code() returns false for
* this code.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param code One of ABS_X, ABS_Y, ...
* @param min The new minimum for this axis
*/
void libevdev_set_abs_minimum(struct libevdev *dev, unsigned int code, int min);
/**
* @ingroup kernel
*
* Change the maximum for the given EV_ABS event code, if the code exists.
* This function has no effect if libevdev_has_event_code() returns false for
* this code.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param code One of ABS_X, ABS_Y, ...
* @param max The new maxium for this axis
*/
void libevdev_set_abs_maximum(struct libevdev *dev, unsigned int code, int max);
/**
* @ingroup kernel
*
* Change the fuzz for the given EV_ABS event code, if the code exists.
* This function has no effect if libevdev_has_event_code() returns false for
* this code.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param code One of ABS_X, ABS_Y, ...
* @param fuzz The new fuzz for this axis
*/
void libevdev_set_abs_fuzz(struct libevdev *dev, unsigned int code, int fuzz);
/**
* @ingroup kernel
*
* Change the flat for the given EV_ABS event code, if the code exists.
* This function has no effect if libevdev_has_event_code() returns false for
* this code.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param code One of ABS_X, ABS_Y, ...
* @param flat The new flat for this axis
*/
void libevdev_set_abs_flat(struct libevdev *dev, unsigned int code, int flat);
/**
* @ingroup kernel
*
* Change the resolution for the given EV_ABS event code, if the code exists.
* This function has no effect if libevdev_has_event_code() returns false for
* this code.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param code One of ABS_X, ABS_Y, ...
* @param resolution The new axis resolution
*/
void libevdev_set_abs_resolution(struct libevdev *dev, unsigned int code, int resolution);
/**
* @ingroup kernel
*
* Change the abs info for the given EV_ABS event code, if the code exists.
* This function has no effect if libevdev_has_event_code() returns false for
* this code.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param code One of ABS_X, ABS_Y, ...
* @param abs The new absolute axis data (min, max, fuzz, flat, resolution)
*/
void libevdev_set_abs_info(struct libevdev *dev, unsigned int code, const struct input_absinfo *abs);
/**
* @ingroup kernel
*
* Forcibly enable an event type on this device, even if the underlying
* device does not support it. While this cannot make the device actually
* report such events, it will now return true for libevdev_has_event_type().
*
* This is a local modification only affecting only this representation of
* this device.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param type The event type to enable (EV_ABS, EV_KEY, ...)
*
* @return 0 on success or -1 otherwise
*
* @see libevdev_has_event_type
*/
int libevdev_enable_event_type(struct libevdev *dev, unsigned int type);
/**
* @ingroup kernel
*
* Forcibly disable an event type on this device, even if the underlying
* device provides it. This effectively mutes the respective set of
* events. libevdev will filter any events matching this type and none will
* reach the caller. libevdev_has_event_type() will return false for this
* type.
*
* In most cases, a caller likely only wants to disable a single code, not
* the whole type. Use libevdev_disable_event_code() for that.
*
* Disabling EV_SYN will not work. Don't shoot yourself in the foot.
* It hurts.
*
* This is a local modification only affecting only this representation of
* this device.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param type The event type to disable (EV_ABS, EV_KEY, ...)
*
* @return 0 on success or -1 otherwise
*
* @see libevdev_has_event_type
* @see libevdev_disable_event_type
*/
int libevdev_disable_event_type(struct libevdev *dev, unsigned int type);
/**
* @ingroup kernel
*
* Forcibly enable an event code on this device, even if the underlying
* device does not support it. While this cannot make the device actually
* report such events, it will now return true for libevdev_has_event_code().
*
* The last argument depends on the type and code:
* - If type is EV_ABS, data must be a pointer to a struct input_absinfo
* containing the data for this axis.
* - If type is EV_REP, daat must be a pointer to a int containing the data
* for this axis
* - For all other types, the argument must be NULL.
*
* This function calls libevdev_enable_event_type() if necessary.
*
* This is a local modification only affecting only this representation of
* this device.
*
* If this function is called with a type of EV_ABS and EV_REP on a device
* that already has the given event code enabled, the values in data
* overwrite the previous values.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param type The event type to enable (EV_ABS, EV_KEY, ...)
* @param code The event code to enable (ABS_X, REL_X, etc.)
* @param data If type is EV_ABS, data points to a struct input_absinfo. If type is EV_REP, data
* points to an integer. Otherwise, data must be NULL.
*
* @return 0 on success or -1 otherwise
*
* @see libevdev_enable_event_type
*/
int libevdev_enable_event_code(struct libevdev *dev, unsigned int type, unsigned int code, const void *data);
/**
* @ingroup kernel
*
* Forcibly disable an event code on this device, even if the underlying
* device provides it. This effectively mutes the respective set of
* events. libevdev will filter any events matching this type and code and
* none will reach the caller. libevdev_has_event_code() will return false for
* this code.
*
* Disabling all event codes for a given type will not disable the event
* type. Use libevdev_disable_event_type() for that.
*
* This is a local modification only affecting only this representation of
* this device.
*
* Disabling codes of type EV_SYN will not work. Don't shoot yourself in the
* foot. It hurts.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param type The event type to disable (EV_ABS, EV_KEY, ...)
* @param code The event code to disable (ABS_X, REL_X, etc.)
*
* @return 0 on success or -1 otherwise
*
* @see libevdev_has_event_code
* @see libevdev_disable_event_type
*/
int libevdev_disable_event_code(struct libevdev *dev, unsigned int type, unsigned int code);
/**
* @ingroup kernel
*
* Set the device's EV_ABS axis to the value defined in the abs
* parameter. This will be written to the kernel.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param code The EV_ABS event code to modify, one of ABS_X, ABS_Y, etc.
* @param abs Axis info to set the kernel axis to
*
* @return 0 on success, or a negative errno on failure
*
* @see libevdev_enable_event_code
*/
int libevdev_kernel_set_abs_info(struct libevdev *dev, unsigned int code, const struct input_absinfo *abs);
/**
* @ingroup kernel
*/
enum libevdev_led_value {
LIBEVDEV_LED_ON = 3, /**< Turn the LED on */
LIBEVDEV_LED_OFF = 4 /**< Turn the LED off */
};
/**
* @ingroup kernel
*
* Turn an LED on or off. Convenience function, if you need to modify multiple
* LEDs simultaneously, use libevdev_kernel_set_led_values() instead.
*
* @note enabling an LED requires write permissions on the device's file descriptor.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param code The EV_LED event code to modify, one of LED_NUML, LED_CAPSL, ...
* @param value Specifies whether to turn the LED on or off
* @return 0 on success, or a negative errno on failure
*/
int libevdev_kernel_set_led_value(struct libevdev *dev, unsigned int code, enum libevdev_led_value value);
/**
* @ingroup kernel
*
* Turn multiple LEDs on or off simultaneously. This function expects a pair
* of LED codes and values to set them to, terminated by a -1. For example, to
* switch the NumLock LED on but the CapsLock LED off, use:
*
* @code
* libevdev_kernel_set_led_values(dev, LED_NUML, LIBEVDEV_LED_ON,
* LED_CAPSL, LIBEVDEV_LED_OFF,
* -1);
* @endcode
*
* If any LED code or value is invalid, this function returns -EINVAL and no
* LEDs are modified.
*
* @note enabling an LED requires write permissions on the device's file descriptor.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param ... A pair of LED_* event codes and libevdev_led_value_t, followed by
* -1 to terminate the list.
* @return 0 on success, or a negative errno on failure
*/
int libevdev_kernel_set_led_values(struct libevdev *dev, ...);
/**
* @ingroup kernel
*
* Set the clock ID to be used for timestamps. Further events from this device
* will report an event time based on the given clock.
*
* This is a modification only affecting this representation of
* this device.
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param clockid The clock to use for future events. Permitted values
* are CLOCK_MONOTONIC and CLOCK_REALTIME (the default).
* @return 0 on success, or a negative errno on failure
*/
int libevdev_set_clock_id(struct libevdev *dev, int clockid);
/**
* @ingroup misc
*
* Helper function to check if an event is of a specific type. This is
* virtually the same as:
*
* ev->type == type
*
* with the exception that some sanity checks are performed to ensure type
* is valid.
*
* @note The ranges for types are compiled into libevdev. If the kernel
* changes the max value, libevdev will not automatically pick these up.
*
* @param ev The input event to check
* @param type Input event type to compare the event against (EV_REL, EV_ABS,
* etc.)
*
* @return 1 if the event type matches the given type, 0 otherwise (or if
* type is invalid)
*/
int libevdev_event_is_type(const struct input_event *ev, unsigned int type);
/**
* @ingroup misc
*
* Helper function to check if an event is of a specific type and code. This
* is virtually the same as:
*
* ev->type == type && ev->code == code
*
* with the exception that some sanity checks are performed to ensure type and
* code are valid.
*
* @note The ranges for types and codes are compiled into libevdev. If the kernel
* changes the max value, libevdev will not automatically pick these up.
*
* @param ev The input event to check
* @param type Input event type to compare the event against (EV_REL, EV_ABS,
* etc.)
* @param code Input event code to compare the event against (ABS_X, REL_X,
* etc.)
*
* @return 1 if the event type matches the given type and code, 0 otherwise
* (or if type/code are invalid)
*/
int libevdev_event_is_code(const struct input_event *ev, unsigned int type, unsigned int code);
/**
* @ingroup misc
*
* @param type The event type to return the name for.
*
* @return The name of the given event type (e.g. EV_ABS) or NULL for an
* invalid type
*
* @note The list of names is compiled into libevdev. If the kernel adds new
* defines for new event types, libevdev will not automatically pick these up.
*/
const char * libevdev_event_type_get_name(unsigned int type);
/**
* @ingroup misc
*
* @param type The event type for the code to query (EV_SYN, EV_REL, etc.)
* @param code The event code to return the name for (e.g. ABS_X)
*
* @return The name of the given event code (e.g. ABS_X) or NULL for an
* invalid type or code
*
* @note The list of names is compiled into libevdev. If the kernel adds new
* defines for new event codes, libevdev will not automatically pick these up.
*/
const char * libevdev_event_code_get_name(unsigned int type, unsigned int code);
/**
* @ingroup misc
*
* @param prop The input prop to return the name for (e.g. INPUT_PROP_BUTTONPAD)
*
* @return The name of the given input prop (e.g. INPUT_PROP_BUTTONPAD) or NULL for an
* invalid property
*
* @note The list of names is compiled into libevdev. If the kernel adds new
* defines for new properties libevdev will not automatically pick these up.
* @note On older kernels input properties may not be defined and
* libevdev_property_get_name() will always return NULL
*/
const char* libevdev_property_get_name(unsigned int prop);
/**
* @ingroup misc
*
* @param type The event type to return the maximum for (EV_ABS, EV_REL, etc.). No max is defined for
* EV_SYN.
*
* @return The max value defined for the given event type, e.g. ABS_MAX for a type of EV_ABS, or -1
* for an invalid type.
*
* @note The max value is compiled into libevdev. If the kernel changes the
* max value, libevdev will not automatically pick these up.
*/
int libevdev_event_type_get_max(unsigned int type);
/**
* @ingroup misc
*
* Look up an event-type by its name. Event-types start with "EV_" followed by
* the name (eg., "EV_ABS"). The "EV_" prefix must be included in the name. It
* returns the constant assigned to the event-type or -1 if not found.
*
* @param name A non-NULL string describing an input-event type ("EV_KEY",
* "EV_ABS", ...), zero-terminated.
*
* @return The given type constant for the passed name or -1 if not found.
*
* @note EV_MAX is also recognized.
*/
int libevdev_event_type_from_name(const char *name);
/**
* @ingroup misc
*
* Look up an event-type by its name. Event-types start with "EV_" followed by
* the name (eg., "EV_ABS"). The "EV_" prefix must be included in the name. It
* returns the constant assigned to the event-type or -1 if not found.
*
* @param name A non-NULL string describing an input-event type ("EV_KEY",
* "EV_ABS", ...).
* @param len The length of the passed string excluding any terminating 0
* character.
*
* @return The given type constant for the passed name or -1 if not found.
*
* @note EV_MAX is also recognized.
*/
int libevdev_event_type_from_name_n(const char *name, size_t len);
/**
* @ingroup misc
*
* Look up an event code by its type and name. Event codes start with a fixed
* prefix followed by their name (eg., "ABS_X"). The prefix must be included in
* the name. It returns the constant assigned to the event code or -1 if not
* found.
*
* You have to pass the event type where to look for the name. For instance, to
* resolve "ABS_X" you need to pass EV_ABS as type and "ABS_X" as string.
* Supported event codes are codes starting with SYN_, KEY_, BTN_, REL_, ABS_,
* MSC_, SND_, SW_, LED_, REP_, FF_.
*
* @param type The event type (EV_* constant) where to look for the name.
* @param name A non-NULL string describing an input-event code ("KEY_A",
* "ABS_X", "BTN_Y", ...), zero-terminated.
*
* @return The given code constant for the passed name or -1 if not found.
*/
int libevdev_event_code_from_name(unsigned int type, const char *name);
/**
* @ingroup misc
*
* Look up an event code by its type and name. Event codes start with a fixed
* prefix followed by their name (eg., "ABS_X"). The prefix must be included in
* the name. It returns the constant assigned to the event code or -1 if not
* found.
*
* You have to pass the event type where to look for the name. For instance, to
* resolve "ABS_X" you need to pass EV_ABS as type and "ABS_X" as string.
* Supported event codes are codes starting with SYN_, KEY_, BTN_, REL_, ABS_,
* MSC_, SND_, SW_, LED_, REP_, FF_.
*
* @param type The event type (EV_* constant) where to look for the name.
* @param name A non-NULL string describing an input-event code ("KEY_A",
* "ABS_X", "BTN_Y", ...).
* @param len The length of the string in @p name excluding any terminating 0
* character.
*
* @return The given code constant for the name or -1 if not found.
*/
int libevdev_event_code_from_name_n(unsigned int type, const char *name,
size_t len);
/**
* @ingroup misc
*
* Look up an input property by its name. Properties start with the fixed
* prefix "INPUT_PROP_" followed by their name (eg., "INPUT_PROP_POINTER").
* The prefix must be included in the name. It returns the constant assigned
* to the property or -1 if not found.
*
* @param name A non-NULL string describing an input property
*
* @return The given code constant for the name or -1 if not found.
*/
int libevdev_property_from_name(const char *name);
/**
* @ingroup misc
*
* Look up an input property by its name. Properties start with the fixed
* prefix "INPUT_PROP_" followed by their name (eg., "INPUT_PROP_POINTER").
* The prefix must be included in the name. It returns the constant assigned
* to the property or -1 if not found.
*
* @param name A non-NULL string describing an input property
* @param len The length of the string in @p name excluding any terminating 0
* character.
*
* @return The given code constant for the name or -1 if not found.
*/
int libevdev_property_from_name_n(const char *name, size_t len);
/**
* @ingroup bits
*
* Get the repeat delay and repeat period values for this device. This
* function is a convenience function only, EV_REP is supported by
* libevdev_get_event_value().
*
* @param dev The evdev device, already initialized with libevdev_set_fd()
* @param delay If not null, set to the repeat delay value
* @param period If not null, set to the repeat period value
*
* @return 0 on success, -1 if this device does not have repeat settings.
*
* @note This function is signal-safe
*
* @see libevdev_get_event_value
*/
int libevdev_get_repeat(const struct libevdev *dev, int *delay, int *period);
/********* DEPRECATED SECTION *********/
#if defined(__GNUC__) && __GNUC__ >= 4
#define LIBEVDEV_DEPRECATED __attribute__ ((deprecated))
#else
#define LIBEVDEV_DEPRECATED
#endif
#ifdef __cplusplus
}
#endif
#endif /* LIBEVDEV_H */
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