build: split rust-lib into rlib & clib

Instead of one static library with all Rust code, split it into two: 1) An rlib Rust library with all Rust code. 2) A staticlib Rust library that links the rlib and provides C stubs. This split allows us to link the Rust library to other Rust code, like doctests or unittests. It also keeps the C-API separate from the Rust code and provides a clean path forward. Signed-off-by: David Rheinsberg <[email protected]>
bus1 · dvdhrm · May 9, 2025 · Apr 24, 2025 · Apr 30, 2025 · Apr 30, 2025
commit 136ffa7f4f303554804cd7e786c80e10afa22f4d
diff --git a/src/clib.rs b/src/clib.rs
@@ -0,0 +1 @@
+//! # C-Rust Bridge
diff --git a/src/meson.build b/src/meson.build
@@ -138,12 +138,18 @@ rust_bus = static_library(
         'rbus',
         structured_sources(
                 [
-                        'lib.rs',
+                        'rlib.rs',
                 ],
                 {
                         'generated': bindgen_generated,
                 },
         ),
+)
+
+crust_bus = static_library(
+        'crbus',
+        ['clib.rs'],
+        link_with: rust_bus,
         rust_abi: 'c',
 )
 
@@ -155,7 +161,7 @@ static_bus = static_library(
                 '-fno-common',
         ],
         dependencies: deps_bus,
-        link_with: rust_bus,
+        link_with: crust_bus,
         pic: true,
 )
 

diff --git a/src/lib.rs → src/rlib.rs b/src/lib.rs → src/rlib.rs
@@ -4,6 +4,11 @@
 //! most executables of dbus-broker as utility library, relying on link-time
 //! garbage collection to drop any unneeded code.
 
+#![no_std]
+
+extern crate alloc;
+extern crate core;
+
 /// # Generated Code
 ///
 /// This module exposes all bindgen-generated (or otherwise generated) code,