Implement fake stdout

Cargo.lock

@@ -1832,7 +1832,7 @@ checksum = "bbd2bcb4c963f2ddae06a2efc7e9f3591312473c50c6685e1f298068316e66fe"
 
 [[package]]
 name = "lemur"
-version = "0.5.0"
+version = "0.5.1"
 dependencies = [
  "anyhow",
  "atoi",

Cargo.toml

@@ -4,7 +4,7 @@ description = "An emulator for the Virtual Boy."
 repository = "https://git.virtual-boy.com/PVB/lemur"
 publish = false
 license = "MIT"
-version = "0.5.0"
+version = "0.5.1"
 edition = "2024"
 
 [dependencies]

src/app.rs

@@ -24,7 +24,8 @@ use crate::{
     persistence::Persistence,
     window::{
         AboutWindow, AppWindow, BgMapWindow, CharacterDataWindow, FrameBufferWindow, GameWindow,
-        GdbServerWindow, HotkeysWindow, InputWindow, ObjectWindow, RegisterWindow, WorldWindow,
+        GdbServerWindow, HotkeysWindow, InputWindow, ObjectWindow, RegisterWindow, TerminalWindow,
+        WorldWindow,
     },
 };
 
@@ -243,6 +244,10 @@ impl ApplicationHandler<UserEvent> for Application {
                 let registers = RegisterWindow::new(sim_id, &self.memory);
                 self.open(event_loop, Box::new(registers));
             }
+            UserEvent::OpenTerminal(sim_id) => {
+                let terminal = TerminalWindow::new(sim_id, &self.client);
+                self.open(event_loop, Box::new(terminal));
+            }
             UserEvent::OpenDebugger(sim_id) => {
                 let debugger =
                     GdbServerWindow::new(sim_id, self.client.clone(), self.proxy.clone());
@@ -513,6 +518,7 @@ pub enum UserEvent {
     OpenWorlds(SimId),
     OpenFrameBuffers(SimId),
     OpenRegisters(SimId),
+    OpenTerminal(SimId),
     OpenDebugger(SimId),
     OpenInput,
     OpenHotkeys,

src/emulator.rs

@@ -169,6 +169,7 @@ pub struct Emulator {
     renderers: HashMap<SimId, TextureSink>,
     messages: HashMap<SimId, mpsc::Sender<Toast>>,
     debuggers: HashMap<SimId, DebugInfo>,
+    stdouts: HashMap<SimId, mpsc::Sender<String>>,
     watched_regions: HashMap<MemoryRange, Weak<MemoryRegion>>,
     eye_contents: Vec<u8>,
     audio_samples: Vec<f32>,
@@ -195,6 +196,7 @@ impl Emulator {
             renderers: HashMap::new(),
             messages: HashMap::new(),
             debuggers: HashMap::new(),
+            stdouts: HashMap::new(),
             watched_regions: HashMap::new(),
             eye_contents: vec![0u8; 384 * 224 * 2],
             audio_samples: Vec::with_capacity(EXPECTED_FRAME_SIZE),
@@ -471,6 +473,20 @@ impl Emulator {
             self.state.store(EmulatorState::Paused, Ordering::Release);
         }
 
+        // stdout
+        self.stdouts.retain(|sim_id, stdout| {
+            let Some(sim) = self.sims.get_mut(sim_id.to_index()) else {
+                return false;
+            };
+            if let Some(text) = sim.take_stdout() {
+                if stdout.send(text).is_err() {
+                    sim.watch_stdout(false);
+                    return false;
+                }
+            }
+            true
+        });
+
         // Debug state
         if state == EmulatorState::Debugging {
             for sim_id in SimId::values() {
@@ -645,6 +661,13 @@ impl Emulator {
                 };
                 sim.remove_watchpoint(address, length, watch);
             }
+            EmulatorCommand::WatchStdout(sim_id, stdout_sink) => {
+                self.stdouts.insert(sim_id, stdout_sink);
+                let Some(sim) = self.sims.get_mut(sim_id.to_index()) else {
+                    return;
+                };
+                sim.watch_stdout(true);
+            }
             EmulatorCommand::SetAudioEnabled(p1, p2) => {
                 self.audio_on[SimId::Player1.to_index()].store(p1, Ordering::Release);
                 self.audio_on[SimId::Player2.to_index()].store(p2, Ordering::Release);
@@ -718,6 +741,7 @@ pub enum EmulatorCommand {
     RemoveBreakpoint(SimId, u32),
     AddWatchpoint(SimId, u32, usize, VBWatchpointType),
     RemoveWatchpoint(SimId, u32, usize, VBWatchpointType),
+    WatchStdout(SimId, mpsc::Sender<String>),
     SetAudioEnabled(bool, bool),
     Link,
     Unlink,

src/emulator/shrooms_vb_core.rs

@@ -230,7 +230,7 @@ extern "C" fn on_write(
     sim: *mut VB,
     address: u32,
     _type: VBDataType,
-    _value: *mut i32,
+    value: *mut i32,
     _cycles: *mut u32,
     _cancel: *mut c_int,
 ) -> c_int {
@@ -238,6 +238,14 @@ extern "C" fn on_write(
     // There is no way for the userdata to be null or otherwise invalid.
     let data: &mut VBState = unsafe { &mut *vb_get_user_data(sim).cast() };
 
+    // If we're monitoring stdout, track this write
+    if let Some(stdout) = data.stdout.as_mut() {
+        let normalized_hw_address = address & 0x0700003f;
+        if normalized_hw_address == 0x02000030 {
+            stdout.push(unsafe { *value } as u8);
+        }
+    }
+
     if let Some(start) = data.write_watchpoints.start_of_range_containing(address) {
         let watch = if data.read_watchpoints.contains(address) {
             VBWatchpointType::Access
@@ -263,6 +271,7 @@ struct VBState {
     breakpoints: Vec<u32>,
     read_watchpoints: AddressSet,
     write_watchpoints: AddressSet,
+    stdout: Option<Vec<u8>>,
 }
 
 impl VBState {
@@ -306,6 +315,7 @@ impl Sim {
             breakpoints: vec![],
             read_watchpoints: AddressSet::new(),
             write_watchpoints: AddressSet::new(),
+            stdout: None,
         };
         unsafe { vb_set_user_data(sim, Box::into_raw(Box::new(state)).cast()) };
         unsafe { vb_set_frame_callback(sim, Some(on_frame)) };
@@ -564,7 +574,9 @@ impl Sim {
         state.write_watchpoints.remove(address, length);
         let needs_execute = state.needs_execute_callback();
         if state.write_watchpoints.is_empty() {
-            unsafe { vb_set_write_callback(self.sim, None) };
+            if state.stdout.is_none() {
+                unsafe { vb_set_write_callback(self.sim, None) };
+            }
             if !needs_execute {
                 unsafe { vb_set_execute_callback(self.sim, None) };
             }
@@ -586,11 +598,40 @@ impl Sim {
         data.breakpoints.clear();
         data.read_watchpoints.clear();
         data.write_watchpoints.clear();
+        let needs_write = data.stdout.is_some();
         unsafe { vb_set_read_callback(self.sim, None) };
-        unsafe { vb_set_write_callback(self.sim, None) };
+        if !needs_write {
+            unsafe { vb_set_write_callback(self.sim, None) };
+        }
         unsafe { vb_set_execute_callback(self.sim, None) };
     }
 
+    pub fn watch_stdout(&mut self, watch: bool) {
+        let data = self.get_state();
+        if watch {
+            if data.stdout.is_none() {
+                data.stdout = Some(vec![]);
+                unsafe { vb_set_write_callback(self.sim, Some(on_write)) };
+            }
+        } else {
+            data.stdout.take();
+            if data.write_watchpoints.is_empty() {
+                unsafe { vb_set_write_callback(self.sim, None) };
+            }
+        }
+    }
+
+    pub fn take_stdout(&mut self) -> Option<String> {
+        let data = self.get_state();
+        let stdout = data.stdout.take()?;
+        let string = match String::from_utf8(stdout) {
+            Ok(str) => str,
+            Err(err) => String::from_utf8_lossy(err.as_bytes()).into_owned(),
+        };
+        data.stdout = Some(vec![]);
+        Some(string)
+    }
+
     pub fn stop_reason(&mut self) -> Option<StopReason> {
         let data = self.get_state();
         let reason = data.stop_reason.take();

src/window.rs

@@ -4,6 +4,7 @@ pub use game::GameWindow;
 pub use gdb::GdbServerWindow;
 pub use hotkeys::HotkeysWindow;
 pub use input::InputWindow;
+pub use terminal::TerminalWindow;
 pub use vip::{
     BgMapWindow, CharacterDataWindow, FrameBufferWindow, ObjectWindow, RegisterWindow, WorldWindow,
 };
@@ -17,6 +18,7 @@ mod game_screen;
 mod gdb;
 mod hotkeys;
 mod input;
+mod terminal;
 mod utils;
 mod vip;
 

src/window/game.rs

@@ -204,6 +204,12 @@ impl GameWindow {
             }
         });
         ui.menu_button("Tools", |ui| {
+            if ui.button("Terminal").clicked() {
+                self.proxy
+                    .send_event(UserEvent::OpenTerminal(self.sim_id))
+                    .unwrap();
+                ui.close_menu();
+            }
             if ui.button("GDB Server").clicked() {
                 self.proxy
                     .send_event(UserEvent::OpenDebugger(self.sim_id))

src/window/game_screen.rs

@@ -71,7 +71,7 @@ impl GameScreen {
                     module: &shader,
                     entry_point: Some(entry_point),
                     targets: &[Some(wgpu::ColorTargetState {
-                        format: wgpu::TextureFormat::Bgra8Unorm,
+                        format: render_state.target_format,
                         blend: Some(wgpu::BlendState::REPLACE),
                         write_mask: wgpu::ColorWrites::ALL,
                     })],

src/window/terminal.rs

@@ -0,0 +1,61 @@
+use std::sync::mpsc;
+
+use egui::{
+    Align, CentralPanel, Context, FontFamily, Label, RichText, ScrollArea, ViewportBuilder,
+    ViewportId,
+};
+
+use crate::emulator::{EmulatorClient, EmulatorCommand, SimId};
+
+use super::AppWindow;
+
+pub struct TerminalWindow {
+    sim_id: SimId,
+    receiver: mpsc::Receiver<String>,
+    text: String,
+}
+
+impl TerminalWindow {
+    pub fn new(sim_id: SimId, client: &EmulatorClient) -> Self {
+        let (sender, receiver) = mpsc::channel();
+        client.send_command(EmulatorCommand::WatchStdout(sim_id, sender));
+        Self {
+            sim_id,
+            receiver,
+            text: String::new(),
+        }
+    }
+}
+
+impl AppWindow for TerminalWindow {
+    fn viewport_id(&self) -> ViewportId {
+        ViewportId::from_hash_of(format!("terminal-{}", self.sim_id))
+    }
+
+    fn sim_id(&self) -> SimId {
+        self.sim_id
+    }
+
+    fn initial_viewport(&self) -> ViewportBuilder {
+        ViewportBuilder::default()
+            .with_title(format!("Terminal ({})", self.sim_id))
+            .with_inner_size((640.0, 480.0))
+    }
+
+    fn show(&mut self, ctx: &Context) {
+        if let Ok(text) = self.receiver.try_recv() {
+            self.text.push_str(&text);
+        }
+        CentralPanel::default().show(ctx, |ui| {
+            ScrollArea::vertical()
+                .stick_to_bottom(true)
+                .auto_shrink([false, false])
+                .show(ui, |ui| {
+                    let label = Label::new(RichText::new(&self.text).family(FontFamily::Monospace))
+                        .halign(Align::LEFT)
+                        .wrap();
+                    ui.add(label);
+                });
+        });
+    }
+}