chore: prioritize http3-quinn over http3-s2n when both features are enabled (avoid compile error)

rpxy-bin/src/main.rs

@@ -15,9 +15,6 @@ use crate::{
 use hot_reload::{ReloaderReceiver, ReloaderService};
 use rpxy_lib::entrypoint;
 
-#[cfg(all(feature = "http3-quinn", feature = "http3-s2n"))]
-compile_error!("feature \"http3-quinn\" and feature \"http3-s2n\" cannot be enabled at the same time");
-
 fn main() {
   init_logger();
 
@@ -29,8 +26,8 @@ fn main() {
   runtime.block_on(async {
     // Initially load options
     let Ok(parsed_opts) = parse_opts() else {
-        error!("Invalid toml file");
-        std::process::exit(1);
+      error!("Invalid toml file");
+      std::process::exit(1);
     };
 
     if !parsed_opts.watch {

rpxy-lib/src/crypto/service.rs

@@ -22,7 +22,7 @@ pub struct ServerCrypto {
   // For Quic/HTTP3, only servers with no client authentication
   #[cfg(feature = "http3-quinn")]
   pub inner_global_no_client_auth: Arc<ServerConfig>,
-  #[cfg(feature = "http3-s2n")]
+  #[cfg(all(feature = "http3-s2n", not(feature = "http3-quinn")))]
   pub inner_global_no_client_auth: s2n_quic_rustls::Server,
   // For TLS over TCP/HTTP2 and 1.1, map of SNI to server_crypto for all given servers
   pub inner_local_map: Arc<SniServerCryptoMap>,
@@ -74,7 +74,7 @@ impl TryInto<Arc<ServerCrypto>> for &ServerCryptoBase {
     Ok(Arc::new(ServerCrypto {
       #[cfg(feature = "http3-quinn")]
       inner_global_no_client_auth: Arc::new(server_crypto_global),
-      #[cfg(feature = "http3-s2n")]
+      #[cfg(all(feature = "http3-s2n", not(feature = "http3-quinn")))]
       inner_global_no_client_auth: server_crypto_global,
       inner_local_map: Arc::new(server_crypto_local_map),
     }))
@@ -200,7 +200,7 @@ impl ServerCryptoBase {
     Ok(server_crypto_global)
   }
 
-  #[cfg(feature = "http3-s2n")]
+  #[cfg(all(feature = "http3-s2n", not(feature = "http3-quinn")))]
   fn build_server_crypto_global(&self) -> Result<s2n_quic_rustls::Server, ReloaderError<ServerCryptoBase>> {
     let mut resolver_global = s2n_quic_rustls::rustls::server::ResolvesServerCertUsingSni::new();
 
@@ -241,7 +241,7 @@ impl ServerCryptoBase {
   }
 }
 
-#[cfg(feature = "http3-s2n")]
+#[cfg(all(feature = "http3-s2n", not(feature = "http3-quinn")))]
 /// This is workaround for the version difference between rustls and s2n-quic-rustls
 fn parse_server_certs_and_keys_s2n(
   certs_and_keys: &CertsAndKeys,

rpxy-lib/src/error.rs

@@ -44,13 +44,13 @@ pub enum RpxyError {
   #[error("Quinn connection error: {0}")]
   QuinnConnectionFailed(#[from] quinn::ConnectionError),
 
-  #[cfg(feature = "http3-s2n")]
+  #[cfg(all(feature = "http3-s2n", not(feature = "http3-quinn")))]
   #[error("s2n-quic validation error: {0}")]
   S2nQuicValidationError(#[from] s2n_quic_core::transport::parameters::ValidationError),
-  #[cfg(feature = "http3-s2n")]
+  #[cfg(all(feature = "http3-s2n", not(feature = "http3-quinn")))]
   #[error("s2n-quic connection error: {0}")]
   S2nQuicConnectionError(#[from] s2n_quic_core::connection::Error),
-  #[cfg(feature = "http3-s2n")]
+  #[cfg(all(feature = "http3-s2n", not(feature = "http3-quinn")))]
   #[error("s2n-quic start error: {0}")]
   S2nQuicStartError(#[from] s2n_quic::provider::StartError),
 

rpxy-lib/src/lib.rs

@@ -27,9 +27,6 @@ pub mod reexports {
   pub use rustls::{Certificate, PrivateKey};
 }
 
-#[cfg(all(feature = "http3-quinn", feature = "http3-s2n"))]
-compile_error!("feature \"http3-quinn\" and feature \"http3-s2n\" cannot be enabled at the same time");
-
 /// Entrypoint that creates and spawns tasks of reverse proxy services
 pub async fn entrypoint<T>(
   proxy_config: &ProxyConfig,
@@ -40,6 +37,9 @@ pub async fn entrypoint<T>(
 where
   T: CryptoSource + Clone + Send + Sync + 'static,
 {
+  #[cfg(all(feature = "http3-quinn", feature = "http3-s2n"))]
+  warn!("Both \"http3-quinn\" and \"http3-s2n\" features are enabled. \"http3-quinn\" will be used");
+
   // For initial message logging
   if proxy_config.listen_sockets.iter().any(|addr| addr.is_ipv6()) {
     info!("Listen both IPv4 and IPv6")

rpxy-lib/src/proxy/mod.rs

@@ -2,7 +2,7 @@ mod proxy_h3;
 mod proxy_main;
 #[cfg(feature = "http3-quinn")]
 mod proxy_quic_quinn;
-#[cfg(feature = "http3-s2n")]
+#[cfg(all(feature = "http3-s2n", not(feature = "http3-quinn")))]
 mod proxy_quic_s2n;
 mod socket;
 

rpxy-lib/src/proxy/proxy_h3.rs

@@ -15,7 +15,7 @@ use tokio::time::timeout;
 
 #[cfg(feature = "http3-quinn")]
 use h3::{quic::BidiStream, quic::Connection as ConnectionQuic, server::RequestStream};
-#[cfg(feature = "http3-s2n")]
+#[cfg(all(feature = "http3-s2n", not(feature = "http3-quinn")))]
 use s2n_quic_h3::h3::{self, quic::BidiStream, quic::Connection as ConnectionQuic, server::RequestStream};
 
 impl<U, T> Proxy<U, T>