implement more robust file watcher

Cargo.lock

@@ -1524,6 +1524,7 @@ dependencies = [
  "minifb",
  "notify",
  "pico-args",
+ "same-file",
  "uw8-tool",
  "wasmtime",
  "wat",

Cargo.toml

@@ -13,4 +13,5 @@ notify = "4"
 pico-args = "0.4"
 curlywas = { git = "https://github.com/exoticorn/curlywas.git", rev = "196719b" }
 wat = "1"
-uw8-tool = { path = "uw8-tool" }
+uw8-tool = { path = "uw8-tool" }
+same-file = "1"

examples/curlywas/line.cwa

@@ -1,102 +1,21 @@
 import "env.memory" memory(4);
 
 import "env.cls" fn cls(i32);
-import "env.setPixel" fn setPixel(i32, i32, i32);
 import "env.time" fn time() -> f32;
+import "env.line" fn line(f32, f32, f32, f32, i32);
 import "env.sin" fn sin(f32) -> f32;
 import "env.cos" fn cos(f32) -> f32;
 
-fn line(x1: f32, y1: f32, x2: f32, y2: f32, col: i32) {
-    let swapTmp: f32;
-    if x1 > x2 {
-        swapTmp = x1;
-        x1 = x2;
-        x2 = swapTmp;
-        swapTmp = y1;
-        y1 = y2;
-        y2 = swapTmp;
-    }
-    if x1 < 0 as f32 & x2 >= 0 as f32 {
-        y1 = y1 + (y2 - y1) * -x1 / (x2 - x1);
-        x1 = 0 as f32;
-    }
-    if x1 < 320 as f32 & x2 >= 320 as f32 {
-        y2 = y2 + (y2 - y1) * (320 as f32 - x2) / (x2 - x1);
-        x2 = 320 as f32;
-    }
-
-    if y1 > y2 {
-        swapTmp = x1;
-        x1 = x2;
-        x2 = swapTmp;
-        swapTmp = y1;
-        y1 = y2;
-        y2 = swapTmp;
-    }
-    if y1 < 0 as f32 & y2 >= 0 as f32 {
-        x1 = x1 + (x2 - x1) * -y1 / (y2 - y1);
-        y1 = 0 as f32;
-    }
-    if y1 < 240 as f32 & y2 >= 240 as f32 {
-        x2 = x2 + (x2 - x1) * (240 as f32 - y2) / (y2 - y1);
-        y2 = 240 as f32;
-    }
-
-    let lazy dx = x2 - x1;
-    let lazy dy = y2 - y1;
-    let max_axis: f32;
-    let p: f32;
-    if abs(dx) >= dy {
-        max_axis = dx;
-        p = x1;
-    } else {
-        max_axis = dy;
-        p = y1;
-    }
-
-    let steps = floor(p + max_axis) as i32 - floor(p) as i32;
-    p = floor(p) + 0.5 - p;
-    if max_axis < 0 as f32 {
-        steps = -steps;
-        p = -p;
-        max_axis = -max_axis;
-    }
-    dx = dx / max_axis;
-    dy = dy / max_axis;
-
-    let f = min(max_axis, max(0 as f32, p));
-    setPixel((x1 + f * dx) as i32, (y1 + f * dy) as i32, col);
-
-    if !steps {
-        return;
-    }
-
-    x1 = x1 + (1 as f32 + p) * dx;
-    y1 = y1 + (1 as f32 + p) * dy;
-
-    p = p + steps as f32;
-
-    loop pixels {
-        if steps := steps - 1 {
-            setPixel(x1 as i32, y1 as i32, col);
-            x1 = x1 + dx;
-            y1 = y1 + dy;
-            branch pixels;
-        }
-    }
-
-    f = min(max_axis, p) - p;
-    setPixel((x1 + f * dx) as i32, (y1 + f * dy) as i32, col);
-}
-
 export fn upd() {
     cls(0);
-//    line(0.0, 4.0, 7.0, -2.0, 15);
-//    return;
     let i: i32;
     loop lines {
-        let angle = i as f32 * (3.1415 / 25.0) + time() * 0.1;
-        line(160.0, 120.0, 160.0 + sin(angle) * 100.0, 120.0 + cos(angle) * 100.0, 47);
+        let angle = i as f32 * (3.1415 / 25.0) + time() * 0.125;
+        line(
+            160 as f32, 120 as f32,
+            160 as f32 + sin(angle) * 100 as f32,
+            120 as f32 + cos(angle) * 100 as f32,
+            47);
         branch_if (i := i + 1)  < 50: lines;
     }
 }

src/filewatcher.rs

@@ -0,0 +1,70 @@
+use anyhow::{bail, Result};
+use notify::{DebouncedEvent, Watcher, RecommendedWatcher};
+use std::{
+    collections::BTreeSet,
+    path::{Path, PathBuf},
+    sync::mpsc,
+    time::Duration,
+};
+
+pub struct FileWatcher {
+    _watcher: RecommendedWatcher,
+    watched_files: BTreeSet<PathBuf>,
+    rx: mpsc::Receiver<DebouncedEvent>,
+}
+
+pub struct FileWatcherBuilder(BTreeSet<PathBuf>);
+
+impl FileWatcher {
+    pub fn builder() -> FileWatcherBuilder {
+        FileWatcherBuilder(BTreeSet::new())
+    }
+
+    pub fn poll_changed_file(&self) -> Result<Option<PathBuf>> {
+        let event = self.rx.try_recv();
+        match event {
+            Ok(DebouncedEvent::Create(path) | DebouncedEvent::Write(path)) => {
+                let handle = same_file::Handle::from_path(&path)?;
+                for file in &self.watched_files {
+                    if handle == same_file::Handle::from_path(file)? {
+                        return Ok(Some(path));
+                    }
+                }
+            }
+            Err(mpsc::TryRecvError::Disconnected) => bail!("File watcher disconnected"),
+            _ => (),
+        }
+
+        Ok(None)
+    }
+}
+
+impl FileWatcherBuilder {
+    pub fn add_file<P: Into<PathBuf>>(&mut self, path: P) -> &mut Self {
+        self.0.insert(path.into());
+        self
+    }
+
+    pub fn build(self) -> Result<FileWatcher> {
+        let mut directories: BTreeSet<&Path> = BTreeSet::new();
+
+        for file in &self.0 {
+            if let Some(directory) = file.parent() {
+                directories.insert(directory);
+            }
+        }
+
+        let (tx, rx) = mpsc::channel();
+        let mut watcher = notify::watcher(tx, Duration::from_millis(100))?;
+
+        for directory in directories {
+            watcher.watch(directory, notify::RecursiveMode::NonRecursive)?;
+        }
+
+        Ok(FileWatcher {
+            _watcher: watcher,
+            watched_files: self.0,
+            rx,
+        })
+    }
+}

src/lib.rs

@@ -10,6 +10,10 @@ use wasmtime::{
     Engine, GlobalType, Memory, MemoryType, Module, Mutability, Store, TypedFunc, ValType,
 };
 
+mod filewatcher;
+
+pub use filewatcher::FileWatcher;
+
 static GAMEPAD_KEYS: &'static [Key] = &[
     Key::Up,
     Key::Down,

src/main.rs

@@ -1,17 +1,14 @@
 use std::fs::File;
 use std::io::prelude::*;
 use std::process;
-use std::sync::mpsc;
-use std::time::Duration;
 use std::{
     path::{Path, PathBuf},
     process::exit,
 };
 
-use anyhow::{bail, Result};
-use notify::{DebouncedEvent, Watcher};
+use anyhow::Result;
 use pico_args::Arguments;
-use uw8::MicroW8;
+use uw8::{FileWatcher, MicroW8};
 
 fn main() -> Result<()> {
     let mut args = Arguments::from_env();
@@ -72,13 +69,14 @@ fn run(mut args: Arguments) -> Result<()> {
         uw8.set_timeout(timeout);
     }
 
-    let (tx, rx) = mpsc::channel();
-    let mut watcher = notify::watcher(tx, Duration::from_millis(100))?;
+    let mut watcher = FileWatcher::builder();
 
     if watch_mode {
-        watcher.watch(&filename, notify::RecursiveMode::NonRecursive)?;
+        watcher.add_file(&filename);
     }
 
+    let watcher = watcher.build()?;
+
     if let Err(err) = start_cart(&filename, &mut uw8, &config) {
         eprintln!("Load error: {}", err);
         if !watch_mode {
@@ -87,14 +85,10 @@ fn run(mut args: Arguments) -> Result<()> {
     }
 
     while uw8.is_open() {
-        match rx.try_recv() {
-            Ok(DebouncedEvent::Create(_) | DebouncedEvent::Write(_)) => {
-                if let Err(err) = start_cart(&filename, &mut uw8, &config) {
-                    eprintln!("Load error: {}", err);
-                }
+        if watcher.poll_changed_file()?.is_some() {
+            if let Err(err) = start_cart(&filename, &mut uw8, &config) {
+                eprintln!("Load error: {}", err);
             }
-            Err(mpsc::TryRecvError::Disconnected) => bail!("File watcher disconnected"),
-            _ => (),
         }
 
         if let Err(err) = uw8.run_frame() {