fix crash when attempting to read zip without rom (#345)

* fix crash when attempting to read zip without rom

* more

src/device.rs

@@ -99,11 +99,11 @@ fn init_rng(device: &mut Device) {
     device.rng = rand_chacha::ChaCha8Rng::seed_from_u64(rng_seed);
 }
 
-fn swap_rom(contents: Vec<u8>) -> Vec<u8> {
+fn swap_rom(contents: Vec<u8>) -> Option<Vec<u8>> {
     let test = u32::from_be_bytes(contents[0..4].try_into().unwrap());
     if test == 0x80371240 {
         // z64
-        contents
+        Some(contents)
     } else if test == 0x37804012 {
         // v64
         let mut data: Vec<u8> = vec![0; contents.len()];
@@ -111,7 +111,7 @@ fn swap_rom(contents: Vec<u8>) -> Vec<u8> {
             let temp = u16::from_ne_bytes(contents[i..i + 2].try_into().unwrap());
             data[i..i + 2].copy_from_slice(&temp.to_be_bytes());
         }
-        return data;
+        Some(data)
     } else if test == 0x40123780 {
         // n64
         let mut data: Vec<u8> = vec![0; contents.len()];
@@ -119,14 +119,13 @@ fn swap_rom(contents: Vec<u8>) -> Vec<u8> {
             let temp = u32::from_ne_bytes(contents[i..i + 4].try_into().unwrap());
             data[i..i + 4].copy_from_slice(&temp.to_be_bytes());
         }
-        return data;
+        Some(data)
     } else {
-        let data: Vec<u8> = vec![];
-        data
+        None
     }
 }
 
-pub fn get_rom_contents(file_path: &std::path::Path) -> Vec<u8> {
+pub fn get_rom_contents(file_path: &std::path::Path) -> Option<Vec<u8>> {
     let mut contents = vec![];
     if file_path.extension().unwrap().eq_ignore_ascii_case("zip") {
         let zip_file = fs::File::open(file_path).unwrap();
@@ -173,7 +172,11 @@ pub fn get_rom_contents(file_path: &std::path::Path) -> Vec<u8> {
         contents = fs::read(file_path).expect("Should have been able to read the file");
     }
 
-    swap_rom(contents)
+    if contents.is_empty() {
+        None
+    } else {
+        swap_rom(contents)
+    }
 }
 
 #[derive(serde::Serialize, serde::Deserialize)]

src/main.rs

@@ -151,22 +151,22 @@ async fn main() {
         }
     } else if args.game.is_some() {
         let file_path = std::path::Path::new(args.game.as_ref().unwrap());
-        let rom_contents = device::get_rom_contents(file_path);
-        if rom_contents.is_empty() {
+        if let Some(rom_contents) = device::get_rom_contents(file_path) {
+            let handle = std::thread::Builder::new()
+                .name("n64".to_string())
+                .stack_size(env!("N64_STACK_SIZE").parse().unwrap())
+                .spawn(move || {
+                    let mut device = device::Device::new();
+                    let overclock = device.ui.config.emulation.overclock;
+                    device::run_game(&mut device, rom_contents, args.fullscreen, overclock);
+                })
+                .unwrap();
+
+            handle.join().unwrap();
+        } else {
             println!("Could not read rom file");
             return;
         }
-        let handle = std::thread::Builder::new()
-            .name("n64".to_string())
-            .stack_size(env!("N64_STACK_SIZE").parse().unwrap())
-            .spawn(move || {
-                let mut device = device::Device::new();
-                let overclock = device.ui.config.emulation.overclock;
-                device::run_game(&mut device, rom_contents, args.fullscreen, overclock);
-            })
-            .unwrap();
-
-        handle.join().unwrap();
     } else {
         let options = eframe::NativeOptions {
             viewport: eframe::egui::ViewportBuilder::default()

src/ui/gui.rs

@@ -445,16 +445,15 @@ pub fn open_rom(app: &mut GopherEguiApp, ctx: &egui::Context, enable_overclock:
                             device.vru_window.gui_ctx = Some(gui_ctx);
                         }
 
-                        let rom_contents = device::get_rom_contents(file.unwrap().path());
-                        if rom_contents.is_empty() {
-                            println!("Could not read rom file");
-                        } else {
+                        if let Some(rom_contents) = device::get_rom_contents(file.unwrap().path()) {
                             device::run_game(
                                 &mut device,
                                 rom_contents,
                                 fullscreen,
                                 enable_overclock,
                             );
+                        } else {
+                            println!("Could not read rom file");
                         }
                     }
                     let result = std::fs::remove_file(running_file);

src/ui/gui/gui_netplay.rs

@@ -430,8 +430,7 @@ fn get_sessions(app: &mut GopherEguiApp, ctx: &egui::Context) {
 }
 
 async fn parse_rom_file(file: rfd::FileHandle, tx: tokio::sync::mpsc::Sender<GameInfo>) {
-    let rom_contents = device::get_rom_contents(file.path());
-    if !rom_contents.is_empty() {
+    if let Some(rom_contents) = device::get_rom_contents(file.path()) {
         let hash = device::cart::rom::calculate_hash(&rom_contents);
         let game_name = ui::storage::get_game_name(&rom_contents);