core/debugger: Implement new GDB stub debugger

src/core/debugger/gdbstub.h

@@ -0,0 +1,47 @@
+// SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include <map>
+#include <memory>
+#include <optional>
+#include <string_view>
+#include <vector>
+
+#include "core/debugger/debugger_interface.h"
+#include "core/debugger/gdbstub_arch.h"
+
+namespace Core {
+
+class System;
+
+class GDBStub : public DebuggerFrontend {
+public:
+    explicit GDBStub(DebuggerBackend& backend, Core::System& system);
+    ~GDBStub();
+
+    void Connected() override;
+    void Stopped(Kernel::KThread* thread) override;
+    std::vector<DebuggerAction> ClientData(std::span<const u8> data) override;
+
+private:
+    void ProcessData(std::vector<DebuggerAction>& actions);
+    void ExecuteCommand(std::string_view packet, std::vector<DebuggerAction>& actions);
+    void HandleQuery(std::string_view command);
+    std::vector<char>::const_iterator CommandEnd() const;
+    std::optional<std::string> DetachCommand();
+    Kernel::KThread* GetThreadByID(u64 thread_id);
+
+    static u8 CalculateChecksum(std::string_view data);
+    void SendReply(std::string_view data);
+    void SendStatus(char status);
+
+private:
+    Core::System& system;
+    std::unique_ptr<GDBStubArch> arch;
+    std::vector<char> current_command;
+    std::map<VAddr, u32> replaced_instructions;
+};
+
+} // namespace Core