first hacky uw8 runner

src/main.rs

@@ -0,0 +1,57 @@
+use std::io::prelude::*;
+use std::{fs::File, time::Instant};
+
+use anyhow::{anyhow, Result};
+use minifb::{Key, Window, WindowOptions};
+use wasmtime::{GlobalType, MemoryType, Mutability, ValType};
+
+fn main() -> Result<()> {
+    let filename = std::env::args()
+        .nth(1)
+        .ok_or_else(|| anyhow!("Missing .uw8 file path"))?;
+    let mut uw8_module = vec![];
+    File::open(filename)?.read_to_end(&mut uw8_module)?;
+
+    let engine = wasmtime::Engine::default();
+    let module = wasmtime::Module::new(&engine, uw8_module)?;
+
+    let mut store = wasmtime::Store::new(&engine, ());
+    let time_global = wasmtime::Global::new(
+        &mut store,
+        GlobalType::new(ValType::I32, Mutability::Var),
+        0.into(),
+    )?;
+    let memory = wasmtime::Memory::new(&mut store, MemoryType::new(2, Some(2)))?;
+
+    let mut linker = wasmtime::Linker::new(&engine);
+    linker.define("uw8", "time", time_global.clone())?;
+    linker.define("uw8", "ram", memory.clone())?;
+
+    let instance = linker.instantiate(&mut store, &module)?;
+    let tic = instance.get_typed_func::<(), (), _>(&mut store, "tic")?;
+
+    let mut buffer = vec![0u32; 320 * 256];
+    let mut window = Window::new("MicroW8", 320, 256, WindowOptions::default())?;
+    window.limit_update_rate(Some(std::time::Duration::from_micros(16666)));
+
+    let start_time = Instant::now();
+
+    while window.is_open() && !window.is_key_down(Key::Escape) {
+        time_global.set(
+            &mut store,
+            wasmtime::Val::I32(start_time.elapsed().as_millis() as i32),
+        )?;
+
+        tic.call(&mut store, ())?;
+
+        let framebuffer = &memory.data(&store)[120..];
+        for i in 0..320 * 256 {
+            let c = framebuffer[i];
+            buffer[i] = (c as u32) * 0x01010101;
+        }
+
+        window.update_with_buffer(&buffer, 320, 256)?;
+    }
+
+    Ok(())
+}