From c7ee3715736d63b3abd15cd5eb5b3c1d143fb96a Mon Sep 17 00:00:00 2001
From: YAMAMOTO Takashi <yamamoto@midokura.com>
Date: Tue, 12 Dec 2023 20:34:55 +0900
Subject: [PATCH] host_wasmtime: make device implementations optional

---
 host_wasmtime/Cargo.toml  | 20 +++++++++++++-------
 host_wasmtime/src/main.rs |  6 ++++++
 2 files changed, 19 insertions(+), 7 deletions(-)

diff --git a/host_wasmtime/Cargo.toml b/host_wasmtime/Cargo.toml
index 345f6a9..df92dbd 100644
--- a/host_wasmtime/Cargo.toml
+++ b/host_wasmtime/Cargo.toml
@@ -5,20 +5,26 @@ edition = "2021"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
+[features]
+default = ["nokhwa", "dummy"]
+nokhwa = ["dep:nokhwa"]
+dummy = ["dep:fraction", "dep:image"]
+
 [dependencies]
+# released versions of nokhwa is a bit broken for avfoundation.
+# https://github.com/l1npengtul/nokhwa/pull/151
+# https://github.com/l1npengtul/nokhwa/pull/152
+nokhwa = {git = "https://github.com/yamt/nokhwa", rev = "0.10+fixes", features = ["input-native", "output-threaded"], optional = true}
+
+fraction = { version = "0.14", optional = true }
+image = { version = "0.24.7", default-features = false, optional = true }
+
 anyhow = "1.0.75"
-fraction = "0.14"
 tracing = { version = "0.1.40", features = ["max_level_trace"] }
 tracing-subscriber = "0.3.18"
-image = { version = "0.24.7", default-features = false }
 async-trait = "0.1.74"
 tokio = { version = "1.35.0", default-features = false }
 
-# released versions of nokhwa is a bit broken for avfoundation.
-# https://github.com/l1npengtul/nokhwa/pull/151
-# https://github.com/l1npengtul/nokhwa/pull/152
-nokhwa = {git = "https://github.com/yamt/nokhwa", rev = "0.10+fixes", features = ["input-native", "output-threaded"]}
-
 # preview2 and component-model are still moving targets.
 wasmtime = { version = "15.0.1", default-features = false, features = ["component-model", "cranelift"]}
 wasmtime-wasi = { version = "15.0.1", default-features = false, features = ["preview2", "sync"] }
diff --git a/host_wasmtime/src/main.rs b/host_wasmtime/src/main.rs
index 7066013..044c871 100644
--- a/host_wasmtime/src/main.rs
+++ b/host_wasmtime/src/main.rs
@@ -18,12 +18,16 @@ use wasmtime_wasi::preview2::WasiCtxBuilder;
 use wasmtime_wasi::preview2::WasiView;
 use wasmtime_wasi::Dir;
 
+#[cfg(feature = "dummy")]
 mod dummy_device;
+#[cfg(feature = "nokhwa")]
 mod nokhwa;
 mod pool;
 mod traits;
 
+#[cfg(feature = "dummy")]
 use dummy_device::DummyDevice;
+#[cfg(feature = "nokhwa")]
 use nokhwa::NokhwaDevice;
 use pool::SimplePool;
 use traits::SensorDevice;
@@ -190,10 +194,12 @@ impl<T: WasiSensorView> wasi::sensor::sensor::HostDevice for T {
     {
         trace!("opening a device {}", device_name);
         let device_impl: Box<dyn SensorDevice + Send + Sync> = match &*device_name {
+            #[cfg(feature = "dummy")]
             "dummy" => Box::new(match DummyDevice::new() {
                 Err(e) => return Ok(Err(e)),
                 Ok(i) => i,
             }),
+            #[cfg(feature = "nokhwa")]
             "nokhwa" => Box::new(match NokhwaDevice::new() {
                 Err(e) => return Ok(Err(e)),
                 Ok(i) => i,