livekit-ffi migration, phase 0

Cargo.toml

@@ -13,6 +13,7 @@ members = [
     "livekit-net",
     "livekit-runtime",
     "livekit-wakeword",
+    "tools/bindgens",
     "libwebrtc",
     "soxr-sys",
     "yuv-sys",

livekit-ffi/Cargo.toml

@@ -38,6 +38,7 @@ downcast-rs = "1.2"
 console-subscriber = { workspace = true, features = ["parking_lot"], optional = true }
 bytes = { workspace = true }
 from_variants = "1.0.2"
+uniffi = { workspace = true, features = ["scaffolding-ffi-buffer-fns"] }
 
 [target.'cfg(target_os = "android")'.dependencies]
 jni = "0.21.1"

livekit-ffi/src/build_info.rs

@@ -0,0 +1,34 @@
+// Copyright 2025 LiveKit, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/// Returns the version specified in the crate's Cargo.toml.
+///
+/// This is the first function exposed over UniFFI from `livekit-ffi`. It carries
+/// no server state and touches no handle store, so downstream SDKs can call it to
+/// prove the UniFFI bindgen toolchain is wired up end-to-end.
+#[uniffi::export]
+pub fn build_version() -> String {
+    env!("CARGO_PKG_VERSION").to_string()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::build_version;
+
+    #[test]
+    fn build_version_matches_cargo_pkg_version() {
+        assert_eq!(build_version(), env!("CARGO_PKG_VERSION"));
+        assert!(!build_version().is_empty());
+    }
+}

livekit-ffi/src/lib.rs

@@ -20,10 +20,13 @@ use thiserror::Error;
 
 mod conversion;
 
+pub mod build_info;
 pub mod cabi;
 pub mod proto;
 pub mod server;
 
+uniffi::setup_scaffolding!();
+
 #[derive(Error, Debug)]
 pub enum FfiError {
     #[error("the server is not configured")]

tools/bindgens/Cargo.toml

@@ -0,0 +1,15 @@
+[package]
+name = "bindgens"
+version = "0.1.0"
+edition.workspace = true
+license.workspace = true
+repository.workspace = true
+description = "Foreign-binding generator CLIs for the LiveKit Rust crates"
+publish = false
+
+# Tooling crate: each bin is a code-generation CLI shared across the workspace's
+# uniffi-exposing crates (livekit-ffi, livekit-uniffi, ...). It has no library
+# target — the bindgens read metadata from an already-compiled cdylib via
+# `--library`, so they never depend on the crates they generate for.
+[dependencies]
+uniffi = { workspace = true, features = ["cli"] }

tools/bindgens/src/bin/uniffi-bindgen.rs

@@ -0,0 +1,22 @@
+// Copyright 2025 LiveKit, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//! The UniFFI bindgen CLI, shared across the workspace.
+//!
+//! Generate bindings from any compiled uniffi cdylib, e.g.:
+//! `cargo run -p bindgens --bin uniffi-bindgen -- generate \
+//!     --library target/debug/liblivekit_ffi.dylib --language python --out-dir <dir>`
+fn main() {
+    uniffi::uniffi_bindgen_main()
+}