Debugger: Add callback for updating while the runloop is suspended; use for GDB

CHANGES

@@ -47,6 +47,7 @@ Other fixes:
 Misc:
  - Core: Suspend runloop when a core crashes
  - Debugger: Save and restore CLI history
+ - Debugger: GDB now works while the game is paused
  - GB Video: Add default SGB border
  - GBA: Automatically skip BIOS if ROM has invalid logo
  - GBA: Refine multiboot detection (fixes mgba.io/i/2192)

include/mgba/debugger/debugger.h

@@ -140,6 +140,7 @@ struct mDebugger {
 	void (*deinit)(struct mDebugger*);
 
 	void (*paused)(struct mDebugger*);
+	void (*update)(struct mDebugger*);
 	void (*entered)(struct mDebugger*, enum mDebuggerEntryReason, struct mDebuggerEntryInfo*);
 	void (*custom)(struct mDebugger*);
 };

src/core/thread.c

@@ -250,7 +250,15 @@ static THREAD_ENTRY _mCoreThreadRun(void* context) {
 			}
 
 			while (impl->state >= mTHREAD_MIN_WAITING && impl->state <= mTHREAD_MAX_WAITING) {
-				ConditionWait(&impl->stateCond, &impl->stateMutex);
+#ifdef USE_DEBUGGERS
+				if (debugger && debugger->update && debugger->state != DEBUGGER_SHUTDOWN) {
+					debugger->update(debugger);
+					ConditionWaitTimed(&impl->stateCond, &impl->stateMutex, 10);
+				} else
+#endif
+				{
+					ConditionWait(&impl->stateCond, &impl->stateMutex);
+				}
 
 				if (impl->sync.audioWait) {
 					MutexUnlock(&impl->stateMutex);

src/debugger/cli-debugger.c

@@ -1124,6 +1124,7 @@ void CLIDebuggerCreate(struct CLIDebugger* debugger) {
 	debugger->d.deinit = _cliDebuggerDeinit;
 	debugger->d.custom = _cliDebuggerCustom;
 	debugger->d.paused = _commandLine;
+	debugger->d.update = NULL;
 	debugger->d.entered = _reportEntry;
 	debugger->d.type = DEBUGGER_CLI;
 

src/debugger/gdb-stub.c

@@ -135,6 +135,12 @@ static void _gdbStubWait(struct mDebugger* debugger) {
 	GDBStubUpdate(stub);
 }
 
+static void _gdbStubUpdate(struct mDebugger* debugger) {
+	struct GDBStub* stub = (struct GDBStub*) debugger;
+	stub->shouldBlock = false;
+	GDBStubUpdate(stub);
+}
+
 static void _ack(struct GDBStub* stub) {
 	char ack = '+';
 	SocketSend(stub->connection, &ack, 1);
@@ -758,6 +764,7 @@ void GDBStubCreate(struct GDBStub* stub) {
 	stub->d.init = 0;
 	stub->d.deinit = _gdbStubDeinit;
 	stub->d.paused = _gdbStubWait;
+	stub->d.update = _gdbStubUpdate;
 	stub->d.entered = _gdbStubEntered;
 	stub->d.custom = _gdbStubPoll;
 	stub->d.type = DEBUGGER_GDB;