1//! Backend API for wayland crates
2//!
3//! This crate provide low-level APIs for interacting with the Wayland protocol,
4//! both client-side and server-side.
5//!
6//! Two possible backends are provided by this crate: the system backend ([`sys`] module)
7//! which relies on the system-provided wayland libraries, and the rust backend ([`rs`] module)
8//! which is an alternative rust implementation of the protocol. The rust backend is always
9//! available, and the system backend is controlled by the `client_system` and `server_system`
10//! cargo features. The `dlopen` cargo feature ensures that the system wayland
11//! libraries are loaded dynamically at runtime, so that your executable does not link them and
12//! can gracefully handle their absence (for example by falling back to X11).
13//!
14//! Additionally the default backends are reexported as toplevel `client` and `server` modules
15//! in this crate. For both client and server, the default backend is the system one if the
16//! associated cargo feature is enabled, and the rust one otherwise.
17//!
18//! Using these reexports is the recommended way to use the crate:
19//! - If you don't need the `*_system` features, an other crate enabling them will not impact your code in
20//! any way as both backends have the same API (the system backend only has more methods)
21//! - If your code needs to do FFI, you just need to directly depend on `wayland-backend` with the
22//! appropriate `*_system` feature enabled, and all the other crates in your dependency tree will
23//! automatically use the `sys` backend.
24//!
25//! Both the `wayland-client` and `wayland-server` crates follow this principle, so everything will "Just
26//! Work" when using them.
27//!
28//! ## Logging
29//!
30//! This crate can generate some runtime error message (notably when a protocol error occurs). By default
31//! those messages are printed to stderr. If you activate the `log` cargo feature, they will instead be
32//! piped through the `log` crate.
33//!
34//! ## raw-window-handle integration
35//!
36//! The `rwh_06` feature activates the [`HasDisplayHandle`][raw_window_handle::HasDisplayHandle] implementation
37//! for the client module [`Backend`][client::Backend].
38//!
39//! ### Deprecated raw-window-handle versions
40//!
41//! While raw-window-handle 0.5 is supported via the `raw-window-handle` feature, it is deprecated and will be removed in the future.
42//!
43//! Note that the `client_system` feature must also be enabled for the implementation to be activated.
44
45#![forbid(improper_ctypes)]
46#![deny(unsafe_op_in_unsafe_fn)]
47#![warn(missing_docs, missing_debug_implementations)]
48// The api modules are imported two times each, this is not accidental
49#![allow(clippy::duplicate_mod)]
50#![cfg_attr(coverage, feature(coverage_attribute))]
51// Doc feature labels can be tested locally by running RUSTDOCFLAGS="--cfg=docsrs" cargo +nightly doc -p <crate>
52#![cfg_attr(docsrs, feature(doc_auto_cfg))]
53
54/// Reexport of the `smallvec` crate, which is part of `wayland-backend`'s public API.
55pub extern crate smallvec;
56
57/// Helper macro for quickly making a [`Message`][crate::protocol::Message]
58#[macro_export]
59macro_rules! message {
60 ($sender_id: expr, $opcode: expr, [$($args: expr),* $(,)?] $(,)?) => {
61 $crate::protocol::Message {
62 sender_id: $sender_id,
63 opcode: $opcode,
64 args: $crate::smallvec::smallvec![$($args),*],
65 }
66 }
67}
68
69// internal imports for dispatching logging depending on the `log` feature
70#[cfg(feature = "log")]
71#[allow(unused_imports)]
72use log::{debug as log_debug, error as log_error, info as log_info, warn as log_warn};
73#[cfg(not(feature = "log"))]
74#[allow(unused_imports)]
75use std::{
76 eprintln as log_error, eprintln as log_warn, eprintln as log_info, eprintln as log_debug,
77};
78
79#[cfg(any(test, feature = "client_system", feature = "server_system"))]
80pub mod sys;
81
82pub mod rs;
83
84#[cfg(not(feature = "client_system"))]
85pub use rs::client;
86#[cfg(feature = "client_system")]
87pub use sys::client;
88
89#[cfg(not(feature = "server_system"))]
90pub use rs::server;
91#[cfg(feature = "server_system")]
92pub use sys::server;
93
94#[cfg(test)]
95mod test;
96
97mod core_interfaces;
98mod debug;
99pub mod protocol;
100mod types;
101
102/*
103 * These trampoline functions need to always be here because the build script cannot
104 * conditionally build their C counterparts on whether the crate is tested or not...
105 * They'll be optimized out when unused.
106 */
107
108#[cfg(feature = "log")]
109#[no_mangle]
110extern "C" fn wl_log_rust_logger_client(msg: *const std::os::raw::c_char) {
111 let cstr = unsafe { std::ffi::CStr::from_ptr(msg) };
112 let text = cstr.to_string_lossy();
113 log::error!("{}", text);
114}
115
116#[cfg(feature = "log")]
117#[no_mangle]
118extern "C" fn wl_log_rust_logger_server(msg: *const std::os::raw::c_char) {
119 let cstr = unsafe { std::ffi::CStr::from_ptr(msg) };
120 let text = cstr.to_string_lossy();
121 log::error!("{}", text);
122}
123