fixes & improvements

arm7tdmi/src/gdb/mod.rs

@@ -13,9 +13,10 @@ pub extern crate gdbstub_arch;
 /// Wait for tcp connection on port
 pub fn wait_for_connection(port: u16) -> io::Result<TcpStream> {
     let bind_addr = format!("0.0.0.0:{port}");
+    info!("waiting for connection on {:?}", bind_addr);
+
     let sock = TcpListener::bind(bind_addr)?;
 
-    info!("waiting for connection");
     // Blocks until a GDB client connects via TCP.
     // i.e: Running `target remote localhost:<port>` from the GDB prompt.
     let (stream, addr) = sock.accept()?;

arm7tdmi/src/gdb/target.rs

@@ -41,7 +41,7 @@ impl<I: MemoryGdbInterface> SingleThreadBase for Arm7tdmiCore<I> {
         &mut self,
         regs: &mut gdbstub_arch::arm::reg::ArmCoreRegs,
     ) -> TargetResult<(), Self> {
-        regs.pc = self.pc;
+        regs.pc = self.get_next_pc();
         regs.lr = self.get_reg(REG_LR);
         regs.sp = self.get_reg(REG_SP);
         regs.r[..].copy_from_slice(&self.gpr[..13]);

core/src/gdb_support.rs

@@ -32,6 +32,7 @@ pub(crate) enum DebuggerRequest {
     Interrupt,
     Resume,
     SingleStep,
+    Reset,
     Disconnected(DisconnectReason),
 }
 
@@ -40,7 +41,7 @@ pub(crate) struct DebuggerRequestHandler {
     request_complete_signal: Arc<(Mutex<bool>, Condvar)>,
     stop_signal: Arc<(Mutex<Option<SingleThreadStopReason<u32>>>, Condvar)>,
     thread: JoinHandle<()>,
-    stopped: bool,
+    pub(crate) stopped: bool,
 }
 
 impl DebuggerRequestHandler {
@@ -123,6 +124,12 @@ impl DebuggerRequestHandler {
                 self.stopped = false;
                 self.complete_request(None)
             }
+            Reset => {
+                debug!("Sending reset interrupt to gba");
+                self.stopped = true;
+                gba.cpu.reset();
+                self.complete_request(Some(SingleThreadStopReason::Signal(Signal::SIGTRAP)))
+            }
             SingleStep => {
                 debug!("Debugger requested single step");
                 self.stopped = true;
@@ -153,6 +160,10 @@ impl DebuggerRequestHandler {
         let mut finished = lock.lock().unwrap();
         *finished = true;
         cvar.notify_one();
+        // wait for the ack
+        while *finished {
+            finished = cvar.wait(finished).unwrap();
+        }
     }
 
     fn complete_request(

core/src/gdb_support/gdb_thread.rs

@@ -3,9 +3,8 @@ use std::sync::{Arc, Condvar, Mutex};
 use arm7tdmi::{
     gdb::wait_for_connection,
     gdbstub::{
-        common::Signal,
         conn::ConnectionExt,
-        stub::{GdbStub, SingleThreadStopReason},
+        stub::GdbStub,
     },
 };
 
@@ -41,14 +40,12 @@ pub(crate) fn start_gdb_server_thread(
         target.disconnect(disconnect_reason);
     });
 
-    let mut debugger = DebuggerRequestHandler {
+    let debugger = DebuggerRequestHandler {
         rx,
         request_complete_signal,
         stop_signal,
         thread,
         stopped: true,
     };
-    debugger.notify_stop_reason(SingleThreadStopReason::Signal(Signal::SIGINT));
-
     Ok(debugger)
 }

core/src/gdb_support/target.rs

@@ -1,4 +1,4 @@
-use std::sync::{Arc, Condvar, Mutex};
+use std::sync::{Arc, Condvar, Mutex, WaitTimeoutResult};
 use std::time::Duration;
 
 /// Implementing the Target trait for gdbstub
@@ -12,6 +12,7 @@ use gdbstub::target::ext::base::singlethread::{
 use gdbstub::target::ext::base::singlethread::{SingleThreadResumeOps, SingleThreadSingleStepOps};
 use gdbstub::target::ext::base::BaseOps;
 use gdbstub::target::ext::breakpoints::BreakpointsOps;
+use gdbstub::target::ext::monitor_cmd::{outputln, ConsoleOutput};
 use gdbstub::target::{self, Target, TargetError, TargetResult};
 use gdbstub_arch::arm::reg::ArmCoreRegs;
 
@@ -42,16 +43,15 @@ impl DebuggerTarget {
     pub fn debugger_request(&mut self, req: DebuggerRequest) {
         let (lock, cvar) = &*self.request_complete_signal;
         let mut finished = lock.lock().unwrap();
-        *finished = false;
-
         // now send the request
         self.tx.send(req).unwrap();
-
         // wait for the notification
         while !*finished {
             finished = cvar.wait(finished).unwrap();
         }
+        // ack the other side we got the signal
         *finished = false;
+        cvar.notify_one();
     }
 
     pub fn wait_for_stop_reason_timeout(
@@ -60,24 +60,22 @@ impl DebuggerTarget {
     ) -> Option<SingleThreadStopReason<u32>> {
         let (lock, cvar) = &*self.stop_signal;
         let mut stop_reason = lock.lock().unwrap();
-        if let Some(stop_reason) = stop_reason.take() {
-            return Some(stop_reason);
-        }
-        let (mut stop_reason, timeout_result) = cvar.wait_timeout(stop_reason, timeout).unwrap();
-        if timeout_result.timed_out() {
-            None
-        } else {
-            Some(stop_reason.take().expect("None is not expected here"))
+        let mut timeout_result: WaitTimeoutResult;
+        while stop_reason.is_none() {
+            (stop_reason, timeout_result) = cvar.wait_timeout(stop_reason, timeout).unwrap();
+            if timeout_result.timed_out() {
+                return None;
+            }
         }
+        Some(stop_reason.take().expect("None is not expected here"))
     }
 
     pub fn wait_for_stop_reason_blocking(&mut self) -> SingleThreadStopReason<u32> {
         let (lock, cvar) = &*self.stop_signal;
         let mut stop_reason = lock.lock().unwrap();
-        if let Some(stop_reason) = stop_reason.take() {
-            return stop_reason;
+        while stop_reason.is_none() {
+            stop_reason = cvar.wait(stop_reason).unwrap();
         }
-        let mut stop_reason = cvar.wait(stop_reason).unwrap();
         stop_reason.take().expect("None is not expected here")
     }
 
@@ -106,6 +104,10 @@ impl Target for DebuggerTarget {
     fn support_memory_map(&mut self) -> Option<target::ext::memory_map::MemoryMapOps<Self>> {
         Some(self)
     }
+
+    fn support_monitor_cmd(&mut self) -> Option<target::ext::monitor_cmd::MonitorCmdOps<'_, Self>> {
+        Some(self)
+    }
 }
 
 impl SingleThreadBase for DebuggerTarget {
@@ -208,3 +210,31 @@ impl target::ext::breakpoints::SwBreakpoint for DebuggerTarget {
         Ok(true)
     }
 }
+
+impl target::ext::monitor_cmd::MonitorCmd for DebuggerTarget {
+    fn handle_monitor_cmd(
+        &mut self,
+        cmd: &[u8],
+        mut out: ConsoleOutput<'_>,
+    ) -> Result<(), Self::Error> {
+        let cmd = match std::str::from_utf8(cmd) {
+            Ok(cmd) => cmd,
+            Err(_) => {
+                outputln!(out, "command must be valid UTF-8");
+                return Ok(());
+            }
+        };
+
+        match cmd {
+            "reset" => {
+                self.debugger_request(DebuggerRequest::Reset);
+                outputln!(out, "sent reset signal");
+            }
+            unk => {
+                outputln!(out, "unknown command: {}", unk);
+            }
+        }
+
+        Ok(())
+    }
+}

platform/rustboyadvance-sdl2/src/main.rs

@@ -27,7 +27,6 @@ use rustboyadvance_core::prelude::*;
 use rustboyadvance_utils::FpsCounter;
 
 const LOG_DIR: &str = ".logs";
-const DEFAULT_GDB_SERVER_PORT: u16 = 1337;
 
 fn ask_download_bios() {
     const OPEN_SOURCE_BIOS_URL: &'static str =
@@ -113,7 +112,7 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
     }
 
     if opts.gdbserver {
-        gba.start_gdbserver(DEFAULT_GDB_SERVER_PORT);
+        gba.start_gdbserver(opts.gdbserver_port);
     }
 
     let mut vsync = true;
@@ -144,7 +143,7 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
                             .unwrap();
                         info!("ending debugger...")
                     }
-                    Scancode::F2 => gba.start_gdbserver(DEFAULT_GDB_SERVER_PORT),
+                    Scancode::F2 => gba.start_gdbserver(opts.gdbserver_port),
                     Scancode::F5 => {
                         info!("Saving state ...");
                         let save = gba.save_state()?;
@@ -159,10 +158,16 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
                         if opts.savestate_path().is_file() {
                             let save = read_bin_file(&opts.savestate_path())?;
                             info!("Restoring state from {:?}...", opts.savestate_path());
-                            let (audio_interface, _sdl_audio_device_new) = audio::create_audio_player(&sdl_context)?;
+                            let (audio_interface, _sdl_audio_device_new) =
+                                audio::create_audio_player(&sdl_context)?;
                             _sdl_audio_device = _sdl_audio_device_new;
                             let rom = opts.read_rom()?.into_boxed_slice();
-                            gba = Box::new(GameBoyAdvance::from_saved_state(&save, bios_bin.clone(), rom, audio_interface)?);
+                            gba = Box::new(GameBoyAdvance::from_saved_state(
+                                &save,
+                                bios_bin.clone(),
+                                rom,
+                                audio_interface,
+                            )?);
                             info!("Restored!");
                         } else {
                             info!("Savestate not created, please create one by pressing F5");

platform/rustboyadvance-sdl2/src/options.rs

@@ -1,4 +1,4 @@
-use std::{path::PathBuf, io};
+use std::{io, path::PathBuf};
 
 use rustboyadvance_core::{
     cartridge::{BackupType, GamepakBuilder},
@@ -33,6 +33,9 @@ pub struct Options {
     #[structopt(short = "d", long)]
     pub gdbserver: bool,
 
+    #[structopt(long = "port", default_value = "1337")]
+    pub gdbserver_port: u16,
+
     /// Force emulation of RTC, use for games that have RTC but the emulator fails to detect
     #[structopt(long)]
     pub rtc: bool,