mirror of
https://gitlab.freedesktop.org/libinput/libei.git
synced 2025-12-30 23:30:08 +01:00
43b383ebdb
WARN 2023/10/11 12:41:19 "_index.md": WARNING you must call the ref / relref shortcode with '% %' instead of '< >' to work correctly for the anchor target attribute
78 lines
2.6 KiB
Markdown
78 lines
2.6 KiB
Markdown
---
|
|
title: EI Protocol documentation
|
|
draft: false
|
|
archetype: "home"
|
|
alwaysopen: true
|
|
---
|
|
|
|
**libei** is a library for Emulated Input, primarily aimed at the Wayland
|
|
stack. It uses a typical client/server separation, with the two parts connected
|
|
via a UNIX socket. In libei parlance, the client-side is called **"EI client"**, the
|
|
server side, typically a Wayland compositor, is called the **"EIS Implementation"**
|
|
(Emulated Input Server). These terms are used throughout this documentation.
|
|
|
|
This documentation details the protocol to communicate between the client side
|
|
and the EIS implementation.
|
|
|
|
A typical Compositor setup using the `libei` and `libeis` [C libraries]({{% relref "libraries" %}}) looks like this:
|
|
|
|
{{< mermaid >}}
|
|
flowchart LR;
|
|
libwayland-server --> c1
|
|
libwayland-server --> c2
|
|
/dev/input/event0 ---> libinput
|
|
/dev/input/event1 ---> libinput
|
|
libei -.-> libeis
|
|
libinput --> inputstack
|
|
inputstack --> libwayland-server
|
|
libeis -.-> inputstack
|
|
subgraph Kernel
|
|
/dev/input/event0
|
|
/dev/input/event1
|
|
end
|
|
subgraph Wayland Compositor
|
|
libwayland-server
|
|
inputstack[input stack]
|
|
libinput
|
|
libeis
|
|
end
|
|
subgraph EI client
|
|
libei
|
|
end
|
|
subgraph Wayland client A
|
|
c1[libwayland-client]
|
|
end
|
|
subgraph Wayland client B
|
|
c2[libwayland-client]
|
|
end
|
|
{{< /mermaid >}}
|
|
|
|
Note how the EI client is roughly equivalent to a physical input device coming
|
|
from the kernel and its events feed into the normal input stack.
|
|
However, the events are distinguishable inside the compositor to allow for
|
|
fine-grained access control on which events may be emulated and when emulation is
|
|
permitted.
|
|
|
|
Events from the EIS implementation would usually feed into the input stack in the
|
|
same way as input events from physical devices. To Wayland clients, they are
|
|
indistinguishable from real devices.
|
|
|
|
The EI client may be a Wayland client itself.
|
|
|
|
## EI Protocol
|
|
|
|
The ei protocol is a public protocol that may be used directly by clients or
|
|
EIS implementations. This documentation describes the protocol, its interfaces
|
|
and how to generate language bindings.
|
|
|
|
If you are looking for easy-to-use C libraries instead, see:
|
|
|
|
- 🥚 [libei](https://libinput.pages.freedesktop.org/libei/api/group__libei.html) for the client side
|
|
- 🍦 [libeis](https://libinput.pages.freedesktop.org/libei/api/group__libeis.html) for the EIS implementation side
|
|
- 🚌 [liboeffis](https://libinput.pages.freedesktop.org/libei/api/group__liboeffis.html) is an helper library for DBus communication with the
|
|
XDG RemoteDesktop portal (`liboeffis`)
|
|
|
|
|
|
# Documentation
|
|
|
|
{{% children %}}
|