Revert "Move to async I/O with Tokio"

This reverts commit e1dbfd7ceb.

.travis.yml

@@ -8,11 +8,12 @@ before_script:
 script:
   - cargo fmt -- --check --verbose
   - cargo test --verbose --all
+  - cargo check --verbose --features=use-openssl
   - cargo check --verbose --no-default-features --features=proxy
-  - cargo check --verbose --no-default-features --features=tls
   - cargo check --verbose --no-default-features --features=minimal
   - cargo check --verbose --no-default-features --features=minimal,debug-calls
-  - cargo check --verbose --no-default-features --features=minimal,no-sync
+  - cargo check --verbose --no-default-features --features=proxy,use-openssl
+  - cargo check --verbose --no-default-features --features=proxy,use-rustls
 
 before_cache:
   - rm -rf "$TRAVIS_HOME/.cargo/registry/src"

Cargo.toml

@@ -1,5 +1,4 @@
 [package]
-edition = "2018"
 name = "electrum-client"
 version = "0.1.0-beta.6"
 authors = ["Alekos Filini <alekos.filini@gmail.com>"]
@@ -23,23 +22,20 @@ path = "src/lib.rs"
 [dependencies]
 log = "^0.4"
 bitcoin = { version = "0.23", features = ["use-serde"] }
-tokio = { version = "0.2", features = ["net", "io-util"] }
-futures = "0.3"
 serde = { version = "^1.0", features = ["derive"] }
 serde_json = { version = "^1.0" }
 
 # Optional dependencies
-tokio-tls = { version = "0.3", optional = true }
-native-tls = { version = "0.2.4", optional = true }
-tokio-socks = { version = "0.2", optional = true }
-
-[dev-dependencies]
-tokio = { version = "0.2", features = ["net", "io-util", "macros"] }
+socks = { version = "^0.3", optional = true }
+openssl = { version = "^0.10", optional = true }
+rustls = { version = "0.16.0", optional = true, features = ["dangerous_configuration"] }
+webpki = { version = "0.21.0", optional = true }
+webpki-roots = { version = "^0.19", optional = true }
 
 [features]
-default = ["tokio-tls", "native-tls", "tokio-socks"]
-no-sync = []
+default = ["socks", "webpki", "webpki-roots", "rustls"]
 minimal = []
 debug-calls = []
-proxy = ["tokio-socks"]
-tls = ["tokio-tls", "native-tls"]
+proxy = ["socks"]
+use-rustls = ["webpki", "webpki-roots", "rustls"]
+use-openssl = ["openssl"]

examples/plaintext.rs

@@ -2,9 +2,8 @@ extern crate electrum_client;
 
 use electrum_client::Client;
 
-#[tokio::main]
-async fn main() {
-    let mut client = Client::new("kirsche.emzy.de:50001").await.unwrap();
-    let res = client.server_features().await;
+fn main() {
+    let mut client = Client::new("kirsche.emzy.de:50001").unwrap();
+    let res = client.server_features();
     println!("{:#?}", res);
 }

examples/ssl.rs

@@ -0,0 +1,9 @@
+extern crate electrum_client;
+
+use electrum_client::Client;
+
+fn main() {
+    let mut client = Client::new_ssl("electrum2.hodlister.co:50002", true).unwrap();
+    let res = client.server_features();
+    println!("{:#?}", res);
+}

examples/tls.rs

@@ -1,12 +0,0 @@
-extern crate electrum_client;
-
-use electrum_client::Client;
-
-#[tokio::main]
-async fn main() {
-    let mut client = Client::new_tls("electrum2.hodlister.co:50002", true)
-        .await
-        .unwrap();
-    let res = client.server_features().await;
-    println!("{:#?}", res);
-}

examples/tor.rs

@@ -2,15 +2,12 @@ extern crate electrum_client;
 
 use electrum_client::Client;
 
-#[tokio::main]
-async fn main() {
+fn main() {
     // NOTE: This assumes Tor is running localy, with an unauthenticated Socks5 listening at
     // localhost:9050
 
-    let mut client = Client::new_proxy("ozahtqwp25chjdjd.onion:50001", "127.0.0.1:9050")
-        .await
-        .unwrap();
-    let res = client.server_features().await;
+    let mut client = Client::new_proxy("ozahtqwp25chjdjd.onion:50001", "127.0.0.1:9050").unwrap();
+    let res = client.server_features();
     println!("{:#?}", res);
 
     // works both with onion v2/v3 (if your Tor supports them)
@@ -18,8 +15,7 @@ async fn main() {
         "v7gtzf7nua6hdmb2wtqaqioqmesdb4xrlly4zwr7bvayxv2bpg665pqd.onion:50001",
         "127.0.0.1:9050",
     )
-    .await
     .unwrap();
-    let res = client.server_features().await;
+    let res = client.server_features();
     println!("{:#?}", res);
 }

src/batch.rs

@@ -5,7 +5,7 @@
 use bitcoin::hashes::hex::ToHex;
 use bitcoin::{Script, Txid};
 
-use crate::types::{Param, ToElectrumScriptHash};
+use types::{Param, ToElectrumScriptHash};
 
 /// Helper structure that caches all the requests before they are actually sent to the server.
 ///

src/lib.rs

@@ -12,22 +12,34 @@
 //! # Example
 //!
 //! ```no_run
-//! use electrum_client::{Client, Error};
+//! use electrum_client::Client;
 //!
-//! #[tokio::main]
-//! async fn main() -> Result<(), Error> {
-//!     let mut client = Client::new("kirsche.emzy.de:50001").await?;
-//!     let response = client.server_features().await?;
-//!
-//!     Ok(())
-//! }
+//! let mut client = Client::new("kirsche.emzy.de:50001")?;
+//! let response = client.server_features()?;
+//! # Ok::<(), electrum_client::Error>(())
 //! ```
 
 pub extern crate bitcoin;
-pub extern crate tokio;
+extern crate log;
+#[cfg(feature = "use-openssl")]
+extern crate openssl;
+#[cfg(all(
+    any(feature = "default", feature = "use-rustls"),
+    not(feature = "use-openssl")
+))]
+extern crate rustls;
+extern crate serde;
+extern crate serde_json;
+#[cfg(any(feature = "default", feature = "proxy"))]
+extern crate socks;
+#[cfg(any(feature = "use-rustls", feature = "default"))]
+extern crate webpki;
+#[cfg(any(feature = "use-rustls", feature = "default"))]
+extern crate webpki_roots;
 
 pub mod batch;
 pub mod client;
+mod stream;
 #[cfg(test)]
 mod test_stream;
 pub mod types;

src/stream.rs

@@ -31,3 +31,10 @@ impl<T: Read + Write> Clone for ClonableStream<T> {
         ClonableStream(Arc::clone(&self.0))
     }
 }
+
+#[cfg(test)]
+impl<T: Read + Write> ClonableStream<T> {
+    pub fn stream(&self) -> Arc<Mutex<T>> {
+        Arc::clone(&self.0)
+    }
+}

src/test_stream.rs

@@ -1,12 +1,7 @@
-use std::io::{Read, Write};
-use std::pin::Pin;
-use std::task::{Context, Poll};
+use std::io::{Read, Result, Write};
 
 use std::fs::File;
 
-use tokio::io::{AsyncRead, AsyncWrite, Result};
-
-#[derive(Debug)]
 pub struct TestStream {
     pub file: File,
     pub buffer: Vec<u8>,
@@ -21,26 +16,18 @@ impl TestStream {
     }
 }
 
-impl AsyncRead for TestStream {
-    fn poll_read(
-        mut self: Pin<&mut Self>,
-        _cx: &mut Context,
-        buf: &mut [u8],
-    ) -> Poll<Result<usize>> {
-        Poll::Ready(self.as_mut().file.read(buf))
+impl Read for TestStream {
+    fn read(&mut self, buf: &mut [u8]) -> Result<usize> {
+        self.file.read(buf)
     }
 }
 
-impl AsyncWrite for TestStream {
-    fn poll_write(mut self: Pin<&mut Self>, _cx: &mut Context, buf: &[u8]) -> Poll<Result<usize>> {
-        Poll::Ready(self.as_mut().buffer.write(buf))
+impl Write for TestStream {
+    fn write(&mut self, buf: &[u8]) -> Result<usize> {
+        self.buffer.write(buf)
     }
 
-    fn poll_flush(mut self: Pin<&mut Self>, _cx: &mut Context) -> Poll<Result<()>> {
-        Poll::Ready(self.as_mut().buffer.flush())
-    }
-
-    fn poll_shutdown(self: Pin<&mut Self>, _cx: &mut Context) -> Poll<Result<()>> {
-        Poll::Ready(Ok(()))
+    fn flush(&mut self) -> Result<()> {
+        self.buffer.flush()
     }
 }

src/types.rs

@@ -242,16 +242,13 @@ pub enum Error {
     InvalidDNSNameError(String),
     /// Missing domain while it was explicitly asked to validate it
     MissingDomain,
-    /// EOF while trying to read from the underlying stream
-    EOF,
 
-    #[cfg(any(feature = "default", feature = "tls"))]
-    /// TLS Error
-    TLS(native_tls::Error),
-
-    #[cfg(any(feature = "default", feature = "proxy"))]
-    /// Proxy Error
-    Proxy(tokio_socks::Error),
+    #[cfg(feature = "use-openssl")]
+    /// Invalid OpenSSL method used
+    InvalidSslMethod(openssl::error::ErrorStack),
+    #[cfg(feature = "use-openssl")]
+    /// SSL Handshake failed with the server
+    SslHandshakeError(openssl::ssl::HandshakeError<std::net::TcpStream>),
 }
 
 macro_rules! impl_error {
@@ -268,9 +265,3 @@ impl_error!(std::io::Error, IOError);
 impl_error!(serde_json::Error, JSON);
 impl_error!(bitcoin::hashes::hex::Error, Hex);
 impl_error!(bitcoin::consensus::encode::Error, Bitcoin);
-
-#[cfg(any(feature = "default", feature = "tls"))]
-impl_error!(native_tls::Error, TLS);
-
-#[cfg(any(feature = "default", feature = "proxy"))]
-impl_error!(tokio_socks::Error, Proxy);