Copyright © 2008-2011 Kristian Høgsberg Copyright © 2010-2011 Intel Corporation Copyright © 2012-2013 Collabora, Ltd. Copyright © 2023 Red Hat, Inc. Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice (including the next paragraph) shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. This is a special interface to setup the client as seen by the EIS implementation. The object for this interface has the fixed object id 0 and only exists until the connection has been set up, see the ei_handshake.connection event. The ei_handshake version is 1 until: - the EIS implementation sends the handshake_version event with a version other than 1, and, in response, - the client sends the handshake_version request with a version equal or lower to the EIS implementation version. The EIS implementation must send the handshake_version event immediately once the physical connection has been established. Once the ei_connection.connection event has been sent the handshake is destroyed by the EIS implementation. Notifies the EIS implementation that this client supports the given version of the ei_handshake interface. The version number must be less than or equal to the version in the handshake_version event sent by the EIS implementation when the connection was established. Immediately after sending this request, the client must assume the negotiated version number for the ei_handshake interface and the EIS implementation may send events and process requests matching that version. This request must be sent exactly once and it must be the first request the client sends. Notify the EIS implementation that configuration is complete. In the future (and possibly after requiring user interaction), the EIS implementation responds by sending the ei_handshake.connection event. This enum denotes context types for the libei context. A context type of receiver is a libei context receiving events from the EIS implementation. A context type of sender is a libei context sending events to the EIS implementation. Notify the EIS implementation of the type of this context. The context types defines whether the client will send events to or receive events from the EIS implementation. Depending on the context type, certain requests must not be used and some events must not be sent by the EIS implementation. This request is optional, the default client type is context_type.receiver. This request must not be sent more than once and must be sent before ei_handshake.finish. Notify the EIS implementation of the client name. The name is a human-presentable UTF-8 string and should represent the client name as accurately as possible. This name may be presented to the user for identification of this client (e.g. to confirm the client has permissions to connect). There is no requirement for the EIS implementation to use this name. For example, where the client is managed through an XDG Desktop Portal an EIS implementation would typically use client identification information sent by the portal instead. This request is optional, the default client name is implementation-defined. This request must not be sent more than once and must be sent before ei_handshake.finish. Notify the EIS implementation that the client supports the given named interface with the given maximum version number. Future objects created by the EIS implementation will use the respective interface version (or any lesser version) as announced by the ei_connection.interface_version event. This request must be sent for the "ei_connection" interface, failing to do so will result in the EIS implementation disconnecting the client on ei_handshake.finish. This request must not be sent for the "ei_handshake" interface, use the ei_handshake.handshake_version request instead. Note that an EIS implementation may consider some interfaces to be required and immediately ei_connection.disconnect a client not supporting those interfaces. This request must not be sent more than once per interface and must be sent before ei_handshake.finish. This event is sent exactly once and immediately after connection to the EIS implementation. In response, the client must send the ei_handshake.handshake_version request with any version up to including the version provided in this event. See the ei_handshake.handshake_version request for details on what happens next. Notifies the client that the EIS implementation supports the given named interface with the given maximum version number. The client must not assume those interfaces are supported unless and until those versions have been received. This request must not be sent for the "ei_handshake" interface, use the handshake_version event instead. This event may be sent by the EIS implementation for any other supported interface (but not necessarily all supported interfaces) before the ei_handshake.connection event. Provides the client with the connection object that is the top-level object for all future requests and events. This event is sent exactly once at some unspecified time after the client sends the ei_handshake.finish request to the EIS implementation. The ei_handshake object will be destroyed by the EIS implementation immediately after this event has been sent, a client must not attempt to use it after that point. The version sent by the EIS implementation is the version of the "ei_connection" interface as announced by ei_handshake.interface_version, or any lower version. The serial number is the start value of the EIS implementation's serial number sequence. Clients must not assume any specific value for this serial number. Any future serial number in any event is monotonically increasing by an unspecified amount. The core connection object. This is the top-level object for any communication with the EIS implementation. Note that for a client to receive this object, it must announce support for this interface in ei_handshake.interface_version. The sync request asks the EIS implementation to emit the 'done' event on the returned ei_callback object. Since requests are handled in-order and events are delivered in-order, this can be used as a synchronization point to ensure all previous requests and the resulting events have been handled. The object returned by this request will be destroyed by the EIS implementation after the callback is fired and as such the client must not attempt to use it after that point. The callback_data in the ei_callback.done event is always zero. Note that for a client to use this request it must announce support for the "ei_callback" interface in ei_handshake.interface_version. It is a protocol violation to request sync without having announced the "ei_callback" interface and the EIS implementation must disconnect the client. A request to the EIS implementation that this client should be disconnected. This is a courtesy request to allow the EIS implementation to distinquish between a client disconnecting on purpose and one disconnecting through the socket becoming invalid. Immediately after sending this request, the client may destroy the ei_connection object and it should close the socket. The EIS implementation will treat the connection as already disconnected on receipt and does not send the ei_connection.disconnect event in response to this request. A reason why a client was disconnected. This enum is intended to provide information to the client on whether it was disconnected as part of normal operations or as result of an error on either the client or EIS implementation side. A nonzero value describes an error, with the generic value "error" (1) reserved as fallback. This enum may be extended in the future, clients must be able to handle values that are not in their supported version of this enum. This event may be sent by the EIS implementation immediately before the client is disconnected. The last_serial argument is set to the last serial number used in a request by the client or zero if the client has not yet issued a request. Where a client is disconnected by EIS on purpose, for example after a user interaction, the reason is disconnect_reason.disconnected (i.e. zero) and the explanation is NULL. Where a client is disconnected due to some invalid request or other protocol error, the reason is one of disconnect_reason (i.e. nonzero) and explanation may contain a string explaining why. This string is intended to help debugging only and is not guaranteed to stay constant. The ei_connection object will be destroyed by the EIS implementation immediately after this event has been sent, a client must not attempt to use it after that point. There is no guarantee this event is sent - the connection may be closed without a disconnection event. Notification that a new seat has been added. A seat is a set of input devices that logically belong together. This event is only sent if the client announced support for the "ei_seat" interface in ei_handshake.interface_version. The interface version is equal or less to the client-supported version in ei_handshake.interface_version for the "ei_seat" interface. Notification that an object ID used in an earlier request was invalid and does not exist. This event is sent by the EIS implementation when an object that does not exist as seen by the EIS implementation. The protocol is asynchronous and this may occur e.g. when the EIS implementation destroys an object at the same time as the client requests functionality from that object. For example, an EIS implementation may send ei_device.destroyed and destroy the device's resources (and protocol object) at the same time as the client attempts to ei_device.start_emulating on that object. It is the client's responsibilty to unwind any state changes done to the object since the last successful message. The ping event asks the client to emit the 'done' event on the provided ei_pingpong object. Since requests are handled in-order and events are delivered in-order, this can be used as a synchronization point to ensure all previous requests and the resulting events have been handled. The object returned by this request must be destroyed by the ei client implementation after the callback is fired and as such the client must not attempt to use it after that point. The callback_data in the resulting ei_pingpong.done request is ignored by the EIS implementation. Note that for a EIS implementation to use this request the client must announce support for this interface in ei_handshake.interface_version. It is a protocol violation to send this event to a client without the "ei_pingpong" interface. Interface for ensuring a roundtrip to the EIS implementation. Clients can handle the 'done' event to get notified when the related request that created the ei_callback object is done. Note that for a client to receive objects of this type, it must announce support for this interface in ei_handshake.interface_version. Notify the client when the related request is done. Immediately after this event the ei_callback object is destroyed by the EIS implementation and as such the client must not attempt to use it after that point. Interface for ensuring a roundtrip to the client implementation. This interface is identical to ei_callback but is intended for the EIS implementation to enforce a roundtrip to the client. Note that for a client to receive objects of this type, it must announce support for this interface in ei_handshake.interface_version. Notify the EIS implementation when the related event is done. Immediately after this request the ei_pingpong object is destroyed by the client and as such must not be used any further. An ei_seat represents a set of input devices that logically belong together. In most cases only one seat is present and all input devices on that seat share the same pointer and keyboard focus. A seat has potential capabilities, a client is expected to bind to those capabilities. The EIS implementation then creates logical input devices based on the capabilities the client is interested in. Immediately after creation of the ei_seat object, the EIS implementation sends a burst of events with information about this seat. This burst of events is terminated by the ei_seat.done event. Note that for a client to receive objects of this type, it must announce support for this interface in ei_handshake.interface_version. Notification that the client is no longer interested in this seat. The EIS implementation will release any resources related to this seat and send the ei_seat.destroyed event once complete. Note that releasing a seat does not guarantee another seat becomes available. In other words, in most single-seat cases, releasing the seat means the connection becomes effectively inert. Bind to the bitmask of capabilities given. The bitmask is zero or more of the masks representing an interface as provided in the ei_seat.capability event. See the ei_seat.capability event documentation for examples. Binding masks that are not supported in the ei_device's interface version is a client bug and may result in disconnection. A client may send this request multiple times to adjust the capabilities it is interested in. If previously-bound capabilities are dropped by the client, the EIS implementation may ei_device.remove devices that have these capabilities. This seat has been removed and a client should release all associated resources. This ei_seat object will be destroyed by the EIS implementation immmediately after after this event is sent and as such the client must not attempt to use it after that point. The name of this seat, if any. This event is optional and sent once immediately after object creation. It is a protocol violation to send this event after the ei_seat.done event. A notification that this seat supports devices with the given interface. The interface is mapped to a bitmask by the EIS implementation. A client may then binary OR these bitmasks in ei_seat.bind. In response, the EIS implementation may then create device based on those bound capabilities. For example, an EIS implementation may map "ei_pointer" to 0x1, "ei_keyboard" to 0x4 and "ei_touchscreen" to 0x8. A client may then ei_seat.bind(0xc) to bind to keyboard and touchscreen but not pointer. Note that as shown in this example the set of masks may be sparse. The value of the mask is contant for the lifetime of the seat but may differ between seats. Note that seat capabilities only represent a mask of possible capabilities on devices in this seat. A capability that is not available on the seat cannot ever be available on any device in this seat. For example, a seat that only has the pointer and keyboard capabilities can never have a device with the touchscreen capability. It is up to the EIS implementation to decide how many (if any) devices with any given capability exist in this seat. Only interfaces that the client announced during ei_handshake.interface_version can be a seat capability. This event is sent multiple times - once per supported interface. The set of capabilities is constant for the lifetime of the seat. It is a protocol violation to send this event after the ei_seat.done event. Notification that the initial burst of events is complete and the client can set up this seat now. It is a protocol violation to send this event more than once. Notification that a new device has been added. This event is only sent if the client announced support for the "ei_device" interface in ei_handshake.interface_version. The interface version is equal or less to the client-supported version in ei_handshake.interface_version for the "ei_device" interface. An ei_device represents a single logical input devices. Like physical input devices an ei_device may have multiple capabilities and may e.g. function as pointer and keyboard. Depending on the ei_handshake.context_type, an ei_device can emulate events via client requests or receive events. It is a protocol violation to emulate certain events on a receiver device, or for the EIS implementation to send certain events to the device. See the individual request/event documentation for details. Note that for a client to receive objects of this type, it must announce support for this interface in ei_handshake.interface_version. Notification that the client is no longer interested in this device. Note that releasing a device does not guarantee another device becomes available. The EIS implementation will release any resources related to this device and send the ei_device.destroyed event once complete. Notify the EIS implementation that the given device is about to start sending events. This should be seen more as a transactional boundary than a time-based boundary. The primary use-cases for this are to allow for setup on the EIS implementation side and/or UI updates to indicate that a device is sending events now and for out-of-band information to sync with a given event sequence. There is no actual requirement that events start immediately once emulation starts and there is no requirement that a client calls ei_device.stop_emulating after the most recent events. For example, in a remote desktop use-case the client would call ei_device.start_emulating once the remote desktop session starts (rather than when the device sends events) and ei_device.stop_emulating once the remote desktop session stops. The sequence number identifies this transaction between start/stop emulating. It must go up by at least 1 on each call to ei_device.start_emulating. Wraparound must be handled by the EIS implementation but callers must ensure that detection of wraparound is possible. It is a protocol violation to request ei_device.start_emulating after ei_device.start_emulating without an intermediate stop_emulating. It is a protocol violation to send this request for a client of an ei_handshake.context_type other than sender. Notify the EIS implementation that the given device is no longer sending events. See ei_device.start_emulating for details. It is a protocol violation to send this request for a client of an ei_handshake.context_type other than sender. Generate a frame event to group the current set of events into a logical hardware event. This function must be called after one or more events on any of ei_pointer, ei_pointer_absolute, ei_scroll, ei_button, ei_keyboard or ei_touchscreen has been requested by the EIS implementation. The EIS implementation should not process changes to the device state until the ei_device.frame event. For example, pressing and releasing a key within the same frame is a logical noop. The given timestamp applies to all events in the current frame. The timestamp must be in microseconds of CLOCK_MONOTONIC. It is a protocol violation to send this request for a client of an ei_handshake.context_type other than sender. This device has been removed and a client should release all associated resources. This ei_device object will be destroyed by the EIS implementation immmediately after after this event is sent and as such the client must not attempt to use it after that point. The name of this device, if any. This event is optional and sent once immediately after object creation. It is a protocol violation to send this event after the ei_device.done event. If the device type is ei_device.device_type.virtual, the device is a virtual device representing input as applied on the EIS implementation's screen. A relative virtual device generates input events in logical pixels, an absolute virtual device generates input events in logical pixels on one of the device's regions. Virtual devices do not have a ei_device.dimension but it may have an ei_device.region. If the device type is ei_device.device_type.physical, the device is a representation of a physical device as if connected to the EIS implementation's host computer. A relative physical device generates input events in mm, an absolute physical device generates input events in mm within the device's specified physical size. Physical devices do not have regions and no ei_device.region events are sent for such devices. The device type, one of virtual or physical. Devices of type ei_device.device_type.physical are supported only clients of type ei_handshake.context_type.receiver. This event is sent once immediately after object creation. It is a protocol violation to send this event after the ei_device.done event. The device dimensions in mm. This event is optional and sent once immediately after object creation. This event is only sent for devices of ei_device.device_type.physical. It is a protocol violation to send this event after the ei_device.done event. Notifies the client of one region. The number of regions is constant for a device and all regions are announced immediately after object creation. A region is rectangular and defined by an x/y offset and a width and a height. A region defines the area on an EIS desktop layout that is accessible by this device - this region may not be the full area of the desktop. Input events may only be sent for points within the regions. The use of regions is private to the EIS compositor and coordinates may not match the size of the actual desktop. For example, a compositor may set a 1920x1080 region to represent a 4K monitor and transparently map input events into the respective true pixels. Absolute devices may have different regions, it is up to the libei client to send events through the correct device to target the right pixel. For example, a dual-head setup my have two absolute devices, the first with a zero offset region spanning the left screen, the second with a nonzero offset spanning the right screen. The physical scale denotes a constant multiplication factor that needs to be applied to any relative movement on this region for that movement to match the same *physical* movement on another region. It is an EIS implementation bug to advertise the touch and/or absolute pointer capability on a device_type.virtual device without advertising an ei_region for this device. This event is optional and sent immediately after object creation. Where a device has multiple regions, this event is sent once for each region. It is a protocol violation to send this event after the ei_device.done event. Note: the fourth argument ('hight') was misspelled when the protocol was declared stable but changing the name is an API breaking change. Notification that a new device has a sub-interface. This event may be sent for the following interfaces: - "ei_pointer" - "ei_pointer_absolute" - "ei_scroll" - "ei_button" - "ei_keyboard" - "ei_touchscreen" The interface version is equal or less to the client-supported version in ei_handshake.interface_version for the respective interface. It is a protocol violation to send a notification for an interface that the client has not bound to with ei_seat.bind. This event is optional and sent immediately after object creation and at most once per interface. It is a protocol violation to send this event after the ei_device.done event. Notification that the initial burst of events is complete and the client can set up this device now. It is a protocol violation to send this event more than once per device. Notification that the device has been resumed by the EIS implementation and (depending on the ei_handshake.context_type) the client may request ei_device.start_emulating or the EIS implementation may ei_device.start_emulating events. It is a client bug to request emulation of events on a device that is not resumed. The EIS implementation may silently discard such events. A newly advertised device is in the ei_device.paused state. Notification that the device has been paused by the EIS implementation and no futher events will be accepted on this device until it is resumed again. For devices of ei_device_setup.context_type sender, the client thus does not need to request ei_device.stop_emulating and may request ei_device.start_emulating after a subsequent ei_device.resumed. For devices of ei_device_setup.context_type receiver and where the EIS implementation did not send a ei_device.stop_emulating prior to this event, the device may send a ei_device.start_emulating event after a subsequent ei_device.resumed event. Pausing a device resets the logical state of the device to neutral. This includes: - any buttons or keys logically down are released - any modifiers logically down are released - any touches logically down are released It is a client bug to request emulation of events on a device that is not resumed. The EIS implementation may silently discard such events. A newly advertised device is in the ei_device.paused state. See the ei_device.start_emulating request for details. It is a protocol violation to send this event for a client of an ei_handshake.context_type other than receiver. See the ei_device.stop_emulating request for details. It is a protocol violation to send this event for a client of an ei_handshake.context_type other than receiver. See the ei_device.frame request for details. It is a protocol violation to send this event for a client of an ei_handshake.context_type other than receiver. Notifies the client that the region specified in the next ei_device.region event is to be assigned the given mapping_id. This ID can be used by the client to identify an external resource that has a relationship with this region. For example the client may receive a data stream with the video data that this region represents. By attaching the same identifier to the data stream and this region the EIS implementation can inform the client that the video data stream and the region represent paired data. This event is optional and sent immediately after object creation but before the corresponding ei_device.region event. Where a device has multiple regions, this event may be sent zero or one time for each region. It is a protocol violation to send this event after the ei_device.done event or to send this event without a corresponding following ei_device.region event. Interface for pointer motion requests and events. This interface is only provided once per device and where a client requests ei_pointer.release the interface does not get re-initialized. An EIS implementation may adjust the behavior of the device (including removing the device) if the interface is releasd. Note that for a client to receive objects of this type, it must announce support for this interface in ei_handshake.interface_version. Notification that the client is no longer interested in this pointer. The EIS implementation will release any resources related to this pointer and send the ei_pointer.destroyed event once complete. Generate a relative motion event on this pointer. It is a client bug to send this request more than once within the same ei_device.frame and the EIS implementation may ignore either or all such requests and/or disconnect the client. It is a protocol violation to send this request for a client of an ei_handshake.context_type other than sender. This object has been removed and a client should release all associated resources. This object will be destroyed by the EIS implementation immmediately after after this event is sent and as such the client must not attempt to use it after that point. See the ei_pointer.motion_relative request for details. It is a protocol violation to send this request for a client of an ei_handshake.context_type other than receiver. Interface for absolute pointer requests and events. This interface is only provided once per device and where a client requests ei_pointer_absolute.release the interface does not get re-initialized. An EIS implementation may adjust the behavior of the device (including removing the device) if the interface is releasd. Note that for a client to receive objects of this type, it must announce support for this interface in ei_handshake.interface_version. Notification that the client is no longer interested in this object. The EIS implementation will release any resources related to this object and send the ei_pointer_absolute.destroyed event once complete. Generate an absolute motion event on this pointer. The x/y coordinates must be within the device's regions or the event is silently discarded. It is a client bug to send this request more than once within the same ei_device.frame and the EIS implementation may ignore either or all such requests and/or disconnect the client. It is a protocol violation to send this request for a client of an ei_handshake.context_type other than sender. This object has been removed and a client should release all associated resources. This object will be destroyed by the EIS implementation immmediately after after this event is sent and as such the client must not attempt to use it after that point. See the ei_pointer_absolute.motion_absolute request for details. It is a protocol violation to send this request for a client of an ei_handshake.context_type other than receiver. Interface for scroll requests and events. This interface is only provided once per device and where a client requests ei_scroll.release the interface does not get re-initialized. An EIS implementation may adjust the behavior of the device (including removing the device) if the interface is releasd. Note that for a client to receive objects of this type, it must announce support for this interface in ei_handshake.interface_version. Notification that the client is no longer interested in this object. The EIS implementation will release any resources related to this object and send the ei_scroll.destroyed event once complete. Generate a a smooth (pixel-precise) scroll event on this pointer. Clients must not send ei_scroll.scroll_discrete events for the same event, the EIS implementation is responsible for emulation of discrete scroll events. It is a client bug to send this request more than once within the same ei_device.frame and the EIS implementation may ignore either or all such requests and/or disconnect the client. It is a protocol violation to send this request for a client of an ei_handshake.context_type other than sender. Generate a a discrete (e.g. wheel) scroll event on this pointer. Clients must not send ei_scroll.scroll events for the same event, the EIS implementation is responsible for emulation of smooth scroll events. A discrete scroll event is based logical scroll units (equivalent to one mouse wheel click). The value for one scroll unit is 120, a fraction or multiple thereof represents a fraction or multiple of a wheel click. It is a client bug to send this request more than once within the same ei_device.frame and the EIS implementation may ignore either or all such requests and/or disconnect the client. It is a protocol violation to send this request for a client of an ei_handshake.context_type other than sender. Generate a a scroll stop or cancel event on this pointer. A scroll stop event notifies the EIS implementation that the interaction causing a scroll motion previously triggered with ei_scroll.scroll or ei_scroll.scroll_discrete has stopped. For example, if all fingers are lifted off a touchpad, two-finger scrolling has logically stopped. The EIS implementation may use this information to e.g. start kinetic scrolling previously based on the previous finger speed. If is_cancel is nonzero, the event represents a cancellation of the current interaction. This indicates that the interaction has stopped to the point where further (server-emulated) scroll events from this device are wrong. It is a client bug to send this request more than once within the same ei_device.frame and the EIS implementation may ignore either or all such requests and/or disconnect the client. It is a client bug to send this request for an axis that had a a nonzero value in either ei_scroll.scroll or ei_scroll.scroll_discrete in the current frame and the EIS implementation may ignore either or all such requests and/or disconnect the client. It is a protocol violation to send this request for a client of an ei_handshake.context_type other than sender. This object has been removed and a client should release all associated resources. This object will be destroyed by the EIS implementation immmediately after after this event is sent and as such the client must not attempt to use it after that point. See the ei_scroll.scroll request for details. It is a protocol violation to send this request for a client of an ei_handshake.context_type other than receiver. See the ei_scroll.scroll_discrete request for details. It is a protocol violation to send this request for a client of an ei_handshake.context_type other than receiver. See the ei_scroll.scroll_stop request for details. It is a protocol violation to send this request for a client of an ei_handshake.context_type other than receiver. Interface for button requests and events. This interface is only provided once per device and where a client requests ei_button.release the interface does not get re-initialized. An EIS implementation may adjust the behavior of the device (including removing the device) if the interface is releasd. Note that for a client to receive objects of this type, it must announce support for this interface in ei_handshake.interface_version. Notification that the client is no longer interested in this object. The EIS implementation will release any resources related to this object and send the ei_button.destroyed event once complete. The logical state of a button. Generate a button event on this pointer. The button codes must match the defines in linux/input-event-codes.h. It is a client bug to send more than one button request for the same button within the same ei_device.frame and the EIS implementation may ignore either or all button state changes and/or disconnect the client. It is a protocol violation to send this request for a client of an ei_handshake.context_type other than sender. This pointer has been removed and a client should release all associated resources. This ei_scroll object will be destroyed by the EIS implementation immmediately after after this event is sent and as such the client must not attempt to use it after that point. See the ei_scroll.button request for details. It is a protocol violation to send this request for a client of an ei_handshake.context_type other than receiver. It is an EIS implementation bug to send more than one button request for the same button within the same ei_device.frame. Interface for keyboard requests and events. This interface is only provided once per device and where a client requests ei_keyboard.release the interface does not get re-initialized. An EIS implementation may adjust the behavior of the device (including removing the device) if the interface is releasd. Note that for a client to receive objects of this type, it must announce support for this interface in ei_handshake.interface_version. Notification that the client is no longer interested in this keyboard. The EIS implementation will release any resources related to this keyboard and send the ei_keyboard.destroyed event once complete. The logical state of a key. Generate a key event on this keyboard. If the device has an ei_keyboard.keymap, the key code corresponds to that keymap. The key codes must match the defines in linux/input-event-codes.h. It is a client bug to send more than one key request for the same key within the same ei_device.frame and the EIS implementation may ignore either or all key state changes and/or disconnect the client. It is a protocol violation to send this request for a client of an ei_handshake.context_type other than sender. This keyboard has been removed and a client should release all associated resources. This ei_keyboard object will be destroyed by the EIS implementation immmediately after after this event is sent and as such the client must not attempt to use it after that point. The keymap type describes how the keymap in the ei_keyboard.keymap event should be parsed. Notification that this device has a keymap. Future key events must be interpreted by the client according to this keymap. For clients of ei_handshake.context_type sender it is the client's responsibility to send the correct ei_keyboard.key keycodes to generate the expected keysym in the EIS implementation. The keymap is constant for the lifetime of the device. This event provides a file descriptor to the client which can be memory-mapped in read-only mode to provide a keyboard mapping description. The fd must be mapped with MAP_PRIVATE by the recipient, as MAP_SHARED may fail. This event is optional and only sent immediately after the ei_keyboard object is created and before the ei_device.done event. It is a protocol violation to send this event after the ei_device.done event. See the ei_keyboard.key request for details. It is a protocol violation to send this request for a client of an ei_handshake.context_type other than receiver. It is a protocol violation to send a key down event in the same frame as a key up event for the same key in the same frame. Notification that the EIS implementation has changed group or modifier states on this device, but not necessarily in response to an ei_keyboard.key event or request. Future ei_keyboard.key requests must take the new group and modifier state into account. This event should be sent any time the modifier state or effective group has changed, whether caused by an ei_keyboard.key event in accordance with the keymap, indirectly due to further handling of an ei_keyboard.key event (e.g., because it triggered a keyboard shortcut that then changed the state), or caused by an unrelated an event (e.g., input from a different keyboard, or a group change triggered by a layout selection widget). For receiver clients, modifiers events will always be properly ordered with received key events, so each key event should be interpreted using the most recently-received modifier state. The server should send this event immediately following the ei_device.frame event for the key press that caused the change. If the state change impacts multiple keyboards, this event should be sent for all of them. For sender clients, the modifiers event is not inherently synchronized with key requests, but the client may send an ei_connection.sync request when synchronization is required. When the corresponding ei_callback.done event is received, all key requests sent prior to the sync request are guaranteed to have been processed, and any directly-resulting modifiers events are guaranteed to have been received. Note, however, that it is still possible for indirectly-triggered state changes, such as via a keyboard shortcut not encoded in the keymap, to be reported after the done event. A client must assume that all modifiers are lifted when it receives an ei_device.paused event. The EIS implementation must send this event after ei_device.resumed to notify the client of any nonzero modifier state. This event does not reqire an ei_device.frame and should be processed immediately by the client. This event is only sent for devices with an ei_keyboard.keymap. Note: A previous version of the documentation instead specified that this event should not be sent in response to ei_keyboard.key events that change the group or modifier state according to the keymap. However, this complicated client implementation and resulted in situations where the client state could get out of sync with the server. Interface for touchscreen requests and events. This interface is only provided once per device and where a client requests ei_touchscreen.release the interface does not get re-initialized. An EIS implementation may adjust the behavior of the device (including removing the device) if the interface is releasd. Note that for a client to receive objects of this type, it must announce support for this interface in ei_handshake.interface_version. Notification that the client is no longer interested in this touchscreen. The EIS implementation will release any resources related to this touch and send the ei_touchscreen.destroyed event once complete. Notifies the EIS implementation about a new touch logically down at the given coordinates. The touchid is a unique id for this touch. Touchids may be re-used after ei_touchscreen.up. The x/y coordinates must be within the device's regions or the event and future ei_touchscreen.motion events with the same touchid are silently discarded. It is a protocol violation to send a touch down in the same frame as a touch motion or touch up. Notifies the EIS implementation about an existing touch changing position to the given coordinates. The touchid is the unique id for this touch previously sent with ei_touchscreen.down. The x/y coordinates must be within the device's regions or the event is silently discarded. It is a protocol violation to send a touch motion in the same frame as a touch down or touch up. Notifies the EIS implementation about an existing touch being logically up. The touchid is the unique id for this touch previously sent with ei_touchscreen.down. If a touch is cancelled via ei_touchscreen.cancel, the ei_touchscreen.up request must not be sent for this same touch. Likewise, a touch released with ei_touchscreen.up must not be cancelled. The touchid may be re-used after this request. It is a protocol violation to send a touch up in the same frame as a touch motion or touch down. Notifies the EIS implementation about an existing touch being cancelled. This typically means that any effects the touch may have had on the user interface should be reverted or otherwise made inconsequential. This request replaces ei_touchscreen.up for the same touch. If a touch is cancelled via ei_touchscreen.cancel, the ei_touchscreen.up request must not be sent for this same touch. Likewise, a touch released with ei_touchscreen.up must not be cancelled. The touchid is the unique id for this touch previously sent with ei_touchscreen.down. The touchid may be re-used after this request. It is a protocol violation to send a touch cancel in the same frame as a touch motion or touch down. This touch has been removed and a client should release all associated resources. This ei_touchscreen object will be destroyed by the EIS implementation immmediately after after this event is sent and as such the client must not attempt to use it after that point. See the ei_touchscreen.down request for details. It is a protocol violation to send this request for a client of an ei_handshake.context_type other than receiver. It is a protocol violation to send a touch down in the same frame as a touch motion or touch up. See the ei_touchscreen.motion request for details. It is a protocol violation to send this request for a client of an ei_handshake.context_type other than receiver. It is a protocol violation to send a touch motion in the same frame as a touch down or touch up. See the ei_touchscreen.up request for details. It is a protocol violation to send this request for a client of an ei_handshake.context_type other than receiver. If a touch is released via ei_touchscreen.up, no ei_touchscreen.cancel event is sent for this same touch. Likewise, a touch released with ei_touchscreen.cancel must not be released via ei_touchscreen.up. It is a protocol violation to send a touch up in the same frame as a touch motion or touch down. See the ei_touchscreen.cancel request for details. It is a protocol violation to send this event for a client of an ei_handshake.context_type other than receiver. If a touch is cancelled via ei_touchscreen.cancel, no ei_touchscreen.up event is sent for this same touch. Likewise, a touch released with ei_touchscreen.up must not be cancelled via ei_touchscreen.cancel. It is a protocol violation to send a touch cancel event in the same frame as a touch motion or touch down.