prs10: improve serial handling

src/lib.rs

@@ -1,6 +1,14 @@
 pub mod sources;
 pub mod targets;
 
+#[macro_export]
+macro_rules! fatal {
+    ($($arg:tt)*) => {{
+        tracing::error!($($arg)*);
+        std::process::exit(-1);
+    }};
+}
+
 use async_trait::async_trait;
 use chrono::{DateTime, Utc};
 use figment::{

src/main.rs

@@ -28,12 +28,29 @@ enum Level {
     Error,
 }
 
+impl From<Level> for tracing::Level {
+    fn from(level: Level) -> Self {
+        match level {
+            Level::Debug => tracing::Level::DEBUG,
+            Level::Info => tracing::Level::INFO,
+            Level::Warn => tracing::Level::WARN,
+            Level::Error => tracing::Level::ERROR,
+        }
+    }
+}
+
+impl Level {
+    fn level(self) -> tracing::Level {
+        self.into()
+    }
+}
+
 #[derive(Parser)]
 struct Args {
     /// TOML configuration to load
     #[arg(short, long, default_value_t = String::from("config.toml"))]
     config_file: String,
-    #[arg(value_enum, default_value_t = Level::Warn)]
+    #[arg(value_enum, default_value_t = Level::Info)]
     log_level: Level,
 }
 
@@ -102,14 +119,16 @@ async fn dummy_consumer(mut chan: ChimemonTargetChannel, cancel: CancellationTok
 
 #[tokio::main(flavor = "current_thread")]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {
+    let args = Args::parse();
     tracing_subscriber::fmt()
-        .with_env_filter(EnvFilter::try_from_default_env().unwrap_or(EnvFilter::default()))
+        .with_env_filter(
+            EnvFilter::try_from_default_env()
+                .unwrap_or(EnvFilter::default().add_directive(args.log_level.level().into())),
+        )
         // .event_format(format::Format::default().pretty())
         .with_span_events(FmtSpan::CLOSE)
         .init();
 
-    let args = Args::parse();
-
     info!("{PROGRAM_NAME} v{VERSION} starting...");
     let fig = Figment::new()
         .merge(Config::default())
@@ -206,6 +225,10 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
     debug!("Task setup complete, tasks: {}", tasks.len());
 
     ctrlc::set_handler(move || {
+        if shutdown_token.is_cancelled() {
+            info!("Forced shutdown");
+            std::process::exit(1);
+        }
         info!("Shutting down");
         shutdown_token.cancel()
     })

src/sources/prs10.rs

@@ -1,11 +1,14 @@
 use std::any::type_name;
 use std::str::FromStr;
 use std::sync::Arc;
+use std::time::Duration;
 
 use async_trait::async_trait;
 use bitflags::bitflags;
 use itertools::Itertools;
-use tokio::io::{AsyncBufReadExt, AsyncWriteExt, BufReader, ReadHalf, WriteHalf};
+use tokio::io::{
+    AsyncBufReadExt, AsyncReadExt, AsyncWriteExt, BufReader, BufWriter, ReadHalf, WriteHalf,
+};
 use tokio::select;
 use tokio::sync::OnceCell;
 use tokio::time::{interval, timeout};
@@ -15,7 +18,7 @@ use tracing::{debug, debug_span, error, info, instrument, warn};
 
 use crate::{
     ChimemonMessage, ChimemonSource, ChimemonSourceChannel, MetricTags, Prs10Config, SourceMetric,
-    SourceReport, SourceReportDetails, SourceStatus,
+    SourceReport, SourceReportDetails, SourceStatus, fatal,
 };
 
 #[derive(Debug)]
@@ -116,6 +119,7 @@ bitflags! {
         const EFC_LOW = (1<<3);
         const CAL_VOLTAGE_HIGH = (1<<4);
         const CAL_VOLTAGE_LOW = (1<<5);
+        const _ = !0;
     }
 }
 
@@ -205,19 +209,28 @@ impl TryFrom<&[u8]> for Prs10Status {
             .map(|s| str::from_utf8(s).unwrap().parse::<u8>())
             .collect_tuple()
             .ok_or("Not enough parts in ST reply")?;
+
+        let volt_lamp_flags = volt_lamp_flags?;
+        let rf_flags = rf_flags?;
+        let temp_flags = temp_flags?;
+        let fll_flags = fll_flags?;
+        let pps_flags = pps_flags?;
+        let system_flags = system_flags?;
+
         Ok(Self {
-            volt_lamp_flags: Prs10PowerLampFlags::from_bits(volt_lamp_flags?)
-                .ok_or("Invalid bits set ({volt_lamp_flags}) for power/lamp flags")?,
-            rf_flags: Prs10RfFlags::from_bits(rf_flags?)
-                .ok_or("Invalid bits set ({rf_flags}) for RF flags")?,
-            temp_flags: Prs10TempFlags::from_bits(temp_flags?)
-                .ok_or("Invalid bits set ({temp_flags}) for temp flags")?,
-            fll_flags: Prs10FllFlags::from_bits(fll_flags?)
-                .ok_or("Invalid bits set ({fll_flags}) for FLL flags")?,
-            pps_flags: Prs10PpsFlags::from_bits(pps_flags?)
-                .ok_or("Invalid bits set ({pps_flags}) for PPS flags")?,
-            system_flags: Prs10SystemFlags::from_bits(system_flags?)
-                .ok_or("Invalid bits set ({system_flags}) for system flags")?,
+            volt_lamp_flags: Prs10PowerLampFlags::from_bits(volt_lamp_flags).ok_or_else(|| {
+                format!("Invalid bits set ({volt_lamp_flags}) for power/lamp flags")
+            })?,
+            rf_flags: Prs10RfFlags::from_bits(rf_flags)
+                .ok_or_else(|| format!("Invalid bits set ({rf_flags}) for RF flags"))?,
+            temp_flags: Prs10TempFlags::from_bits(temp_flags)
+                .ok_or_else(|| format!("Invalid bits set ({temp_flags}) for temp flags"))?,
+            fll_flags: Prs10FllFlags::from_bits(fll_flags)
+                .ok_or_else(|| format!("Invalid bits set ({fll_flags}) for FLL flags"))?,
+            pps_flags: Prs10PpsFlags::from_bits(pps_flags)
+                .ok_or_else(|| format!("Invalid bits set ({pps_flags}) for PPS flags"))?,
+            system_flags: Prs10SystemFlags::from_bits(system_flags)
+                .ok_or_else(|| format!("Invalid bits set ({system_flags}) for system flags"))?,
         })
     }
 }
@@ -313,7 +326,7 @@ pub struct Prs10Monitor {
     name: String,
     config: Prs10Config,
     rx: ReadHalf<SerialStream>,
-    tx: WriteHalf<SerialStream>,
+    tx: BufWriter<WriteHalf<SerialStream>>,
     info: OnceCell<Prs10Info>,
 }
 
@@ -324,8 +337,9 @@ impl Prs10Monitor {
 
     #[instrument(level = "debug", skip_all, fields(cmd = String::from_utf8_lossy(cmd).to_string()))]
     pub async fn cmd_response(&mut self, cmd: &[u8]) -> Result<Vec<u8>, std::io::Error> {
-        self.tx.write_all(cmd).await.unwrap();
-        self.tx.write_u8(b'\r').await.unwrap();
+        self.tx.write_all(cmd).await?;
+        self.tx.write_u8(b'\r').await?;
+        self.tx.flush().await?;
         let mut reader = BufReader::new(&mut self.rx);
         let mut buf = Vec::new();
         let read = timeout(self.config.timeout, reader.read_until(b'\r', &mut buf)).await??;
@@ -476,6 +490,20 @@ impl Prs10Monitor {
             }),
         }))
     }
+
+    async fn reset_rx_state(&mut self) -> Result<(), Box<dyn std::error::Error>> {
+        // flush any pending input and potential responses from the receiver side
+        self.tx.write_u8(b'\r').await?;
+        self.tx.flush().await?;
+        let mut discard = vec![];
+        loop {
+            match timeout(Duration::from_millis(100), self.rx.read_buf(&mut discard)).await {
+                Ok(_) => discard.clear(),
+                Err(_) => break,
+            }
+        }
+        Ok(())
+    }
 }
 
 #[async_trait]
@@ -488,15 +516,28 @@ impl ChimemonSource for Prs10Monitor {
             .parity(tokio_serial::Parity::None)
             .stop_bits(tokio_serial::StopBits::One)
             .flow_control(tokio_serial::FlowControl::None);
-        let mut port = SerialStream::open(&builder).expect("Must be able to open serial port");
-        port.set_exclusive(true).expect("Can't lock serial port");
+        let mut port = SerialStream::open(&builder).unwrap_or_else(|e| {
+            fatal!(
+                "Failed to open serial port `{}` ({})",
+                config.port,
+                e.to_string()
+            )
+        });
+        port.set_exclusive(true).unwrap_or_else(|e| {
+            fatal!(
+                "Can't lock serial port `{}` ({})",
+                config.port,
+                e.to_string()
+            )
+        });
         info!(
             "Opened serial port {}@{}",
             port.name().unwrap(),
             port.baud_rate().unwrap()
         );
-        let (rx, tx) = tokio::io::split(port);
 
+        let (rx, tx) = tokio::io::split(port);
+        let tx = BufWriter::new(tx);
         Self {
             name: name.to_owned(),
             config,
@@ -505,10 +546,15 @@ impl ChimemonSource for Prs10Monitor {
             info: OnceCell::new(),
         }
     }
+
     async fn run(mut self, chan: ChimemonSourceChannel, cancel: CancellationToken) {
         info!("PRS10 task started");
+        if let Err(e) = self.reset_rx_state().await {
+            error!(error = ?e, "Error clearing PRS10 RX state");
+            return;
+        }
         if let Err(e) = self.set_info().await {
-            error!("Error starting PRS10: {e:?}");
+            error!(error = ?e, "Error starting PRS10");
             return;
         }
         info!(