examples: don't force io::Error from errors

examples/client.rs

@@ -1,3 +1,4 @@
+use std::error::Error as StdError;
 use std::fs::File;
 use std::io;
 use std::io::BufReader;
@@ -32,7 +33,7 @@ struct Options {
 }
 
 #[tokio::main]
-async fn main() -> io::Result<()> {
+async fn main() -> Result<(), Box<dyn StdError + Send + Sync + 'static>> {
     let options: Options = argh::from_env();
 
     let addr = (options.host.as_str(), options.port)
@@ -46,7 +47,7 @@ async fn main() -> io::Result<()> {
     if let Some(cafile) = &options.cafile {
         let mut pem = BufReader::new(File::open(cafile)?);
         for cert in rustls_pemfile::certs(&mut pem) {
-            root_cert_store.add(cert?).unwrap();
+            root_cert_store.add(cert?)?;
         }
     } else {
         root_cert_store.extend(webpki_roots::TLS_SERVER_ROOTS.iter().cloned());
@@ -61,10 +62,7 @@ async fn main() -> io::Result<()> {
 
     let (mut stdin, mut stdout) = (tokio_stdin(), tokio_stdout());
 
-    let domain = ServerName::try_from(domain.as_str())
-        .map_err(|_| io::Error::new(io::ErrorKind::InvalidInput, "invalid dnsname"))?
-        .to_owned();
-
+    let domain = ServerName::try_from(domain.as_str())?.to_owned();
     let mut stream = connector.connect(domain, stream).await?;
     stream.write_all(content.as_bytes()).await?;
 

examples/server.rs

@@ -3,6 +3,7 @@ use std::io::{self, BufReader, ErrorKind};
 use std::net::ToSocketAddrs;
 use std::path::{Path, PathBuf};
 use std::sync::Arc;
+use std::error::Error as StdError;
 
 use argh::FromArgs;
 use rustls::pki_types::{CertificateDer, PrivateKeyDer};
@@ -45,7 +46,7 @@ fn load_key(path: &Path) -> io::Result<PrivateKeyDer<'static>> {
 }
 
 #[tokio::main]
-async fn main() -> io::Result<()> {
+async fn main() -> Result<(), Box<dyn StdError + Send + Sync + 'static>> {
     let options: Options = argh::from_env();
 
     let addr = options
@@ -59,8 +60,7 @@ async fn main() -> io::Result<()> {
 
     let config = rustls::ServerConfig::builder()
         .with_no_client_auth()
-        .with_single_cert(certs, key)
-        .map_err(|err| io::Error::new(io::ErrorKind::InvalidInput, err))?;
+        .with_single_cert(certs, key)?;
     let acceptor = TlsAcceptor::from(Arc::new(config));
 
     let listener = TcpListener::bind(&addr).await?;