refactor: make it rusty

Author: Sl1mb0

guests/python/build.rs

@@ -64,13 +64,12 @@ fn download_wasi_sdk() -> Result<(), Box<dyn std::error::Error>> {
     let mut reader = response.into_reader();
     let mut hasher = sha2::Sha256::new();
     let mut buffer = [0u8; 8192];
-    loop {
-        let n = reader.read(&mut buffer)?;
-        if n == 0 {
-            break;
-        }
-        hasher.update(&buffer[..n]);
-        file.write_all(&buffer[..n])?;
+    while let Ok(n) = reader.read(&mut buffer)
+        && n > 0
+    {
+        let chunk = &buffer[..n];
+        hasher.update(chunk);
+        file.write_all(chunk)?;
     }
     let digest = hasher.finalize();
     let hex_digest = format!("{:x}", digest);