Add embassy-std-examples

Cargo.toml

@@ -13,7 +13,8 @@ members = [
 # for all crates in the workspace together, including it would result in
 # incompatible features enabled in embassy.
 exclude = [
-    "embassy-std"
+    "embassy-std",
+    "embassy-std-examples",
 ]
 
 [profile.dev]

embassy-std-examples/Cargo.toml

@@ -0,0 +1,14 @@
+[package]
+authors = ["Dario Nieuwenhuis <dirbaio@dirbaio.net>"]
+edition = "2018"
+name = "embassy-std-examples"
+version = "0.1.0"
+
+[dependencies]
+async-io = "1.3.1"
+embassy = { version = "0.1.0", path = "../embassy", features = ["log"] }
+embassy-std = { version = "0.1.0", path = "../embassy-std" }
+env_logger = "0.8.2"
+futures = { version = "0.3.8", default-features = false, features = ["async-await"] }
+log = "0.4.11"
+nix = "0.19.1"

embassy-std-examples/src/bin/serial.rs

@@ -0,0 +1,57 @@
+#![feature(type_alias_impl_trait)]
+
+#[path = "../serial_port.rs"]
+mod serial_port;
+
+use async_io::Async;
+use embassy::executor::task;
+use embassy::io::{AsyncBufRead, AsyncBufReadExt, AsyncWrite, AsyncWriteExt};
+use embassy::util::Forever;
+use embassy_std::Executor;
+use log::*;
+use nix::sys::termios;
+
+use self::serial_port::SerialPort;
+
+#[task]
+async fn run() {
+    // Open the serial port.
+    let baudrate = termios::BaudRate::B115200;
+    let port = SerialPort::new("/dev/ttyACM0", baudrate).unwrap();
+    //let port = Spy::new(port);
+
+    // Use async_io's reactor for async IO.
+    // This demonstrates how embassy's executor can drive futures from another IO library.
+    // Essentially, async_io::Async converts from AsRawFd+Read+Write to futures's AsyncRead+AsyncWrite
+    let port = Async::new(port).unwrap();
+
+    // This implements futures's AsyncBufRead based on futures's AsyncRead
+    let port = futures::io::BufReader::new(port);
+
+    // We can then use FromStdIo to convert from futures's AsyncBufRead+AsyncWrite
+    // to embassy's AsyncBufRead+AsyncWrite
+    let mut port = embassy::io::FromStdIo::new(port);
+
+    info!("Serial opened!");
+
+    loop {
+        let mut buf = [0u8; 256];
+        let n = port.read(&mut buf).await.unwrap();
+        info!("read {:?}", &buf[..n]);
+    }
+}
+
+static EXECUTOR: Forever<Executor> = Forever::new();
+
+fn main() {
+    env_logger::builder()
+        .filter_level(log::LevelFilter::Debug)
+        .filter_module("async_io", log::LevelFilter::Info)
+        .format_timestamp_nanos()
+        .init();
+
+    let executor = EXECUTOR.put(Executor::new());
+    executor.run(|spawner| {
+        spawner.spawn(run()).unwrap();
+    });
+}

embassy-std-examples/src/bin/tick.rs

@@ -0,0 +1,29 @@
+#![feature(type_alias_impl_trait)]
+
+use embassy::executor::task;
+use embassy::time::{Duration, Timer};
+use embassy::util::Forever;
+use embassy_std::Executor;
+use log::*;
+
+#[task]
+async fn run() {
+    loop {
+        info!("tick");
+        Timer::after(Duration::from_secs(1)).await;
+    }
+}
+
+static EXECUTOR: Forever<Executor> = Forever::new();
+
+fn main() {
+    env_logger::builder()
+        .filter_level(log::LevelFilter::Debug)
+        .format_timestamp_nanos()
+        .init();
+
+    let executor = EXECUTOR.put(Executor::new());
+    executor.run(|spawner| {
+        spawner.spawn(run()).unwrap();
+    });
+}

embassy-std-examples/src/serial_port.rs

@@ -0,0 +1,71 @@
+use nix::fcntl::OFlag;
+use nix::sys::termios;
+use nix::Error;
+use std::io;
+use std::os::unix::io::{AsRawFd, RawFd};
+
+pub struct SerialPort {
+    fd: RawFd,
+}
+
+impl SerialPort {
+    pub fn new<'a, P: ?Sized + nix::NixPath>(
+        path: &P,
+        baudrate: termios::BaudRate,
+    ) -> io::Result<Self> {
+        let fd = nix::fcntl::open(
+            path,
+            OFlag::O_RDWR | OFlag::O_NOCTTY | OFlag::O_NONBLOCK,
+            nix::sys::stat::Mode::empty(),
+        )
+        .map_err(to_io_error)?;
+
+        let mut cfg = termios::tcgetattr(fd).map_err(to_io_error)?;
+        cfg.input_flags = termios::InputFlags::empty();
+        cfg.output_flags = termios::OutputFlags::empty();
+        cfg.control_flags = termios::ControlFlags::empty();
+        cfg.local_flags = termios::LocalFlags::empty();
+        termios::cfmakeraw(&mut cfg);
+        cfg.input_flags |= termios::InputFlags::IGNBRK;
+        cfg.control_flags |= termios::ControlFlags::CREAD;
+        //cfg.control_flags |= termios::ControlFlags::CRTSCTS;
+        termios::cfsetospeed(&mut cfg, baudrate).map_err(to_io_error)?;
+        termios::cfsetispeed(&mut cfg, baudrate).map_err(to_io_error)?;
+        termios::cfsetspeed(&mut cfg, baudrate).map_err(to_io_error)?;
+        // Set VMIN = 1 to block until at least one character is received.
+        cfg.control_chars[termios::SpecialCharacterIndices::VMIN as usize] = 1;
+        termios::tcsetattr(fd, termios::SetArg::TCSANOW, &cfg).map_err(to_io_error)?;
+        termios::tcflush(fd, termios::FlushArg::TCIOFLUSH).map_err(to_io_error)?;
+
+        Ok(Self { fd })
+    }
+}
+
+impl AsRawFd for SerialPort {
+    fn as_raw_fd(&self) -> RawFd {
+        self.fd
+    }
+}
+
+impl io::Read for SerialPort {
+    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+        nix::unistd::read(self.fd, buf).map_err(to_io_error)
+    }
+}
+
+impl io::Write for SerialPort {
+    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
+        nix::unistd::write(self.fd, buf).map_err(to_io_error)
+    }
+
+    fn flush(&mut self) -> io::Result<()> {
+        Ok(())
+    }
+}
+
+fn to_io_error(e: Error) -> io::Error {
+    match e {
+        Error::Sys(errno) => errno.into(),
+        e => io::Error::new(io::ErrorKind::InvalidInput, e),
+    }
+}

test-build.sh

@@ -3,8 +3,7 @@
 set -euxo pipefail
 
 # embassy std
-(cd embassy; cargo build --features log,std)
-(cd embassy-std; cargo build)
+(cd embassy-std-examples; cargo build)
 
 # embassy embedded
 (cd embassy; cargo build --target thumbv7em-none-eabi)