Impl sceSystemServiceLoadExec (#3647)

* Add support for restarting the emulator with new configurations

- Implement `Restart` function in `Emulator` to enable process relaunch with updated parameters.
- Modify `sceSystemServiceLoadExec` to use the restart functionality.

* Add logging for emulator restart and system service load execution

* Add IPC emulator PID output command

Impl `PID` output command to return the emulator process ID
- required for launches supporting emulator restart

* Add log file append mode support (used after restarting to keep the same log file)

* Keep game root between restarts

* add --wait-for-debugger option flag

* add --wait-for-pid flag

used for sync between parent & child process during restart

* impl restart via ipc

* fix override game root

* add qt flags to allow restart

CMakeLists.txt

@@ -824,6 +824,8 @@ set(CORE src/core/aerolib/stubs.cpp
          ${DEV_TOOLS}
          src/core/debug_state.cpp
          src/core/debug_state.h
+         src/core/debugger.cpp
+         src/core/debugger.h
          src/core/linker.cpp
          src/core/linker.h
          src/core/memory.cpp

src/common/logging/backend.cpp

@@ -61,8 +61,9 @@ private:
  */
 class FileBackend {
 public:
-    explicit FileBackend(const std::filesystem::path& filename)
-        : file{filename, FS::FileAccessMode::Write, FS::FileType::TextFile} {}
+    explicit FileBackend(const std::filesystem::path& filename, bool should_append = false)
+        : file{filename, should_append ? FS::FileAccessMode::Append : FS::FileAccessMode::Write,
+               FS::FileType::TextFile} {}
 
     ~FileBackend() = default;
 
@@ -145,6 +146,11 @@ public:
         initialization_in_progress_suppress_logging = false;
     }
 
+    static void ResetInstance() {
+        initialization_in_progress_suppress_logging = true;
+        instance.reset();
+    }
+
     static bool IsActive() {
         return instance != nullptr;
     }
@@ -157,6 +163,10 @@ public:
         instance->StopBackendThread();
     }
 
+    static void SetAppend() {
+        should_append = true;
+    }
+
     Impl(const Impl&) = delete;
     Impl& operator=(const Impl&) = delete;
 
@@ -218,7 +228,7 @@ public:
 
 private:
     Impl(const std::filesystem::path& file_backend_filename, const Filter& filter_)
-        : filter{filter_}, file_backend{file_backend_filename} {}
+        : filter{filter_}, file_backend{file_backend_filename, should_append} {}
 
     ~Impl() = default;
 
@@ -264,6 +274,7 @@ private:
     }
 
     static inline std::unique_ptr<Impl, decltype(&Deleter)> instance{nullptr, Deleter};
+    static inline bool should_append{false};
 
     Filter filter;
     DebuggerBackend debugger_backend{};
@@ -292,6 +303,11 @@ void Stop() {
     Impl::Stop();
 }
 
+void Denitializer() {
+    Impl::Stop();
+    Impl::ResetInstance();
+}
+
 void SetGlobalFilter(const Filter& filter) {
     Impl::Instance().SetGlobalFilter(filter);
 }
@@ -300,6 +316,10 @@ void SetColorConsoleBackendEnabled(bool enabled) {
     Impl::Instance().SetColorConsoleBackendEnabled(enabled);
 }
 
+void SetAppend() {
+    Impl::SetAppend();
+}
+
 void FmtLogMessageImpl(Class log_class, Level log_level, const char* filename,
                        unsigned int line_num, const char* function, const char* format,
                        const fmt::format_args& args) {

src/common/logging/backend.h

@@ -21,9 +21,14 @@ void Start();
 /// Explictily stops the logger thread and flushes the buffers
 void Stop();
 
+/// Closes log files and stops the logger
+void Denitializer();
+
 /// The global filter will prevent any messages from even being processed if they are filtered.
 void SetGlobalFilter(const Filter& filter);
 
 void SetColorConsoleBackendEnabled(bool enabled);
 
+void SetAppend();
+
 } // namespace Common::Log

src/core/debugger.cpp

@@ -0,0 +1,99 @@
+//  SPDX-FileCopyrightText: Copyright 2025 shadPS4 Emulator Project
+//  SPDX-License-Identifier: GPL-2.0-or-later
+
+#include "debugger.h"
+
+#include <iostream>
+#include <thread>
+
+#if defined(_WIN32)
+#include <Windows.h>
+#include <debugapi.h>
+#elif defined(__linux__)
+#include <filesystem>
+#include <fstream>
+#elif defined(__APPLE__)
+#include <errno.h>
+#include <signal.h>
+#include <sys/sysctl.h>
+#include <sys/types.h>
+#include <unistd.h>
+#endif
+
+bool Core::Debugger::IsDebuggerAttached() {
+#if defined(_WIN32)
+    return IsDebuggerPresent();
+#elif defined(__linux__)
+    std::ifstream status_file("/proc/self/status");
+    std::string line;
+    while (std::getline(status_file, line)) {
+        if (line.starts_with("TracerPid:")) {
+            std::string tracer_pid = line.substr(10);
+            tracer_pid.erase(0, tracer_pid.find_first_not_of(" \t"));
+            return tracer_pid != "0";
+        }
+    }
+    return false;
+#elif defined(__APPLE__)
+    int mib[4];
+    struct kinfo_proc info;
+    size_t size = sizeof(info);
+
+    mib[0] = CTL_KERN;
+    mib[1] = KERN_PROC;
+    mib[2] = KERN_PROC_PID;
+    mib[3] = getpid();
+
+    if (sysctl(mib, 4, &info, &size, nullptr, 0) == 0) {
+        return (info.kp_proc.p_flag & P_TRACED) != 0;
+    }
+    return false;
+#else
+#error "Unsupported platform"
+#endif
+}
+
+void Core::Debugger::WaitForDebuggerAttach() {
+    int count = 0;
+    while (!IsDebuggerAttached()) {
+        std::this_thread::sleep_for(std::chrono::milliseconds(200));
+        if (--count <= 0) {
+            count = 10;
+            std::cerr << "Waiting for debugger to attach..." << std::endl;
+        }
+    }
+}
+int Core::Debugger::GetCurrentPid() {
+#if defined(_WIN32)
+    return GetCurrentProcessId();
+#elif defined(__APPLE__) || defined(__linux__)
+    return getpid();
+#else
+#error "Unsupported platform"
+#endif
+}
+
+void Core::Debugger::WaitForPid(int pid) {
+#if defined(_WIN32)
+    HANDLE process_handle = OpenProcess(SYNCHRONIZE, FALSE, pid);
+    if (process_handle != nullptr) {
+        std::cerr << "Waiting for process " << pid << " to exit..." << std::endl;
+        WaitForSingleObject(process_handle, INFINITE);
+        CloseHandle(process_handle);
+    }
+#elif defined(__linux__)
+    std::string proc_path = "/proc/" + std::to_string(pid);
+
+    while (std::filesystem::exists(proc_path)) {
+        std::this_thread::sleep_for(std::chrono::milliseconds(500));
+        std::cerr << "Waiting for process " << pid << " to exit..." << std::endl;
+    }
+#elif defined(__APPLE__)
+    while (kill(pid, 0) == 0) {
+        std::this_thread::sleep_for(std::chrono::milliseconds(500));
+        std::cerr << "Waiting for process " << pid << " to exit..." << std::endl;
+    }
+#else
+#error "Unsupported platform"
+#endif
+}

src/core/debugger.h

@@ -0,0 +1,16 @@
+//  SPDX-FileCopyrightText: Copyright 2025 shadPS4 Emulator Project
+//  SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+namespace Core::Debugger {
+
+bool IsDebuggerAttached();
+
+void WaitForDebuggerAttach();
+
+int GetCurrentPid();
+
+void WaitForPid(int pid);
+
+} // namespace Core::Debugger

src/core/ipc/ipc.cpp

@@ -1,4 +1,4 @@
-//  SPDX-FileCopyrightText: Copyright 2024 shadPS4 Emulator Project
+//  SPDX-FileCopyrightText: Copyright 2025 shadPS4 Emulator Project
 //  SPDX-License-Identifier: GPL-2.0-or-later
 
 #include "ipc.h"
@@ -12,6 +12,7 @@
 #include "common/thread.h"
 #include "common/types.h"
 #include "core/debug_state.h"
+#include "core/debugger.h"
 #include "input/input_handler.h"
 #include "sdl_window.h"
 
@@ -40,6 +41,7 @@
  * Command list:
  * - CAPABILITIES:
  *   - ENABLE_MEMORY_PATCH: enables PATCH_MEMORY command
+ *   - ENABLE_EMU_CONTROL: enables PAUSE, RESUME, STOP, TOGGLE_FULLSCREEN commands
  * - INPUT CMD:
  *   - RUN: start the emulator execution
  *   - START: start the game execution
@@ -53,7 +55,7 @@
  *   - STOP: stop and quit the emulator
  *   - TOGGLE_FULLSCREEN: enable / disable fullscreen
  * - OUTPUT CMD:
- *   - N/A
+ *   - RESTART(argn: number, argv: ...string): Request restart of the emulator, must call STOP
  **/
 
 void IPC::Init() {
@@ -81,6 +83,15 @@ void IPC::Init() {
     }
 }
 
+void IPC::SendRestart(const std::vector<std::string>& args) {
+    std::cerr << ";RESTART\n";
+    std::cerr << ";" << args.size() << "\n";
+    for (const auto& arg : args) {
+        std::cerr << ";" << arg << "\n";
+    }
+    std::cerr.flush();
+}
+
 void IPC::InputLoop() {
     auto next_str = [&] -> const std::string& {
         static std::string line_buffer;

src/core/ipc/ipc.h

@@ -6,7 +6,9 @@
 #include "common/singleton.h"
 
 #include <semaphore>
+#include <string>
 #include <thread>
+#include <vector>
 
 class IPC {
     bool enabled{false};
@@ -34,6 +36,8 @@ public:
         start_semaphore.acquire();
     }
 
+    void SendRestart(const std::vector<std::string>& args);
+
 private:
     [[noreturn]] void InputLoop();
 };

src/core/libraries/system/systemservice.cpp

@@ -3,9 +3,12 @@
 
 #include "common/config.h"
 #include "common/logging/log.h"
+#include "common/singleton.h"
+#include "core/file_sys/fs.h"
 #include "core/libraries/libs.h"
 #include "core/libraries/system/systemservice.h"
 #include "core/libraries/system/systemservice_error.h"
+#include "emulator.h"
 
 namespace Libraries::SystemService {
 
@@ -1866,8 +1869,18 @@ int PS4_SYSV_ABI sceSystemServiceLaunchWebBrowser() {
     return ORBIS_OK;
 }
 
-int PS4_SYSV_ABI sceSystemServiceLoadExec() {
-    LOG_ERROR(Lib_SystemService, "(STUBBED) called");
+int PS4_SYSV_ABI sceSystemServiceLoadExec(const char* path, const char* argv[]) {
+    LOG_DEBUG(Lib_SystemService, "called");
+    auto emu = Common::Singleton<Core::Emulator>::Instance();
+    auto mnt = Common::Singleton<Core::FileSys::MntPoints>::Instance();
+    auto hostPath = mnt->GetHostPath(std::string_view(path));
+    std::vector<std::string> args;
+    if (argv != nullptr) {
+        for (const char** ptr = argv; *ptr != nullptr; ptr++) {
+            args.push_back(std::string(*ptr));
+        }
+    }
+    emu->Restart(hostPath, args);
     return ORBIS_OK;
 }
 

src/core/libraries/system/systemservice.h

@@ -501,7 +501,7 @@ int PS4_SYSV_ABI sceSystemServiceLaunchEventDetails();
 int PS4_SYSV_ABI sceSystemServiceLaunchTournamentList();
 int PS4_SYSV_ABI sceSystemServiceLaunchTournamentsTeamProfile();
 int PS4_SYSV_ABI sceSystemServiceLaunchWebBrowser();
-int PS4_SYSV_ABI sceSystemServiceLoadExec();
+int PS4_SYSV_ABI sceSystemServiceLoadExec(const char* path, const char* argv[]);
 int PS4_SYSV_ABI sceSystemServiceNavigateToAnotherApp();
 int PS4_SYSV_ABI sceSystemServiceNavigateToGoBack();
 int PS4_SYSV_ABI sceSystemServiceNavigateToGoBackWithValue();

src/core/linker.cpp

@@ -55,7 +55,7 @@ Linker::Linker() : memory{Memory::Instance()} {}
 
 Linker::~Linker() = default;
 
-void Linker::Execute(const std::vector<std::string> args) {
+void Linker::Execute(const std::vector<std::string>& args) {
     if (Config::debugDump()) {
         DebugDump();
     }
@@ -115,7 +115,7 @@ void Linker::Execute(const std::vector<std::string> args) {
                                                                  0, "SceKernelInternalMemory");
     ASSERT_MSG(ret == 0, "Unable to perform sceKernelInternalMemory mapping");
 
-    main_thread.Run([this, module, args](std::stop_token) {
+    main_thread.Run([this, module, &args](std::stop_token) {
         Common::SetCurrentThreadName("GAME_MainThread");
         if (auto& ipc = IPC::Instance()) {
             ipc.WaitForStart();
@@ -140,9 +140,9 @@ void Linker::Execute(const std::vector<std::string> args) {
         params.argc = 1;
         params.argv[0] = "eboot.bin";
         if (!args.empty()) {
-            params.argc = args.size() + 1;
-            for (int i = 0; i < args.size() && i < 32; i++) {
-                params.argv[i + 1] = args[i].c_str();
+            params.argc = args.size();
+            for (int i = 0; i < args.size() && i < 33; i++) {
+                params.argv[i] = args[i].c_str();
             }
         }
         params.entry_addr = module->GetEntryAddress();

src/core/linker.h

@@ -151,7 +151,7 @@ public:
     void Relocate(Module* module);
     bool Resolve(const std::string& name, Loader::SymbolType type, Module* module,
                  Loader::SymbolRecord* return_info);
-    void Execute(const std::vector<std::string> args = {});
+    void Execute(const std::vector<std::string>& args = {});
     void DebugDump();
 
 private:

src/emulator.cpp

@@ -3,15 +3,18 @@
 
 #include <filesystem>
 #include <fstream>
+#include <iostream>
 #include <set>
 #include <sstream>
 #include <fmt/core.h>
+#include <fmt/xchar.h>
 #include <hwinfo/hwinfo.h>
 
 #include "common/config.h"
 #include "common/debug.h"
 #include "common/logging/backend.h"
 #include "common/logging/log.h"
+#include "core/ipc/ipc.h"
 #ifdef ENABLE_QT_GUI
 #include <QtCore>
 #endif
@@ -19,9 +22,6 @@
 #ifdef ENABLE_DISCORD_RPC
 #include "common/discord_rpc_handler.h"
 #endif
-#ifdef _WIN32
-#include <WinSock2.h>
-#endif
 #include "common/elf_info.h"
 #include "common/memory_patcher.h"
 #include "common/ntapi.h"
@@ -29,6 +29,7 @@
 #include "common/polyfill_thread.h"
 #include "common/scm_rev.h"
 #include "common/singleton.h"
+#include "core/debugger.h"
 #include "core/devtools/widget/module_list.h"
 #include "core/file_format/psf.h"
 #include "core/file_format/trp.h"
@@ -45,6 +46,15 @@
 #include "emulator.h"
 #include "video_core/renderdoc.h"
 
+#ifdef _WIN32
+#include <WinSock2.h>
+#endif
+
+#ifndef _WIN32
+#include <sys/wait.h>
+#include <unistd.h>
+#endif
+
 Frontend::WindowSDL* g_window = nullptr;
 
 namespace Core {
@@ -63,25 +73,35 @@ Emulator::Emulator() {
 
 Emulator::~Emulator() {}
 
-void Emulator::Run(std::filesystem::path file, const std::vector<std::string> args) {
+void Emulator::Run(std::filesystem::path file, std::vector<std::string> args,
+                   std::optional<std::filesystem::path> p_game_folder) {
+    if (waitForDebuggerBeforeRun) {
+        Debugger::WaitForDebuggerAttach();
+    }
+
     if (std::filesystem::is_directory(file)) {
         file /= "eboot.bin";
     }
 
-    const auto eboot_name = file.filename().string();
-
-    auto game_folder = file.parent_path();
-    if (const auto game_folder_name = game_folder.filename().string();
-        game_folder_name.ends_with("-UPDATE") || game_folder_name.ends_with("-patch")) {
-        // If an executable was launched from a separate update directory,
-        // use the base game directory as the game folder.
-        const std::string base_name = game_folder_name.substr(0, game_folder_name.rfind('-'));
-        const auto base_path = game_folder.parent_path() / base_name;
-        if (std::filesystem::is_directory(base_path)) {
-            game_folder = base_path;
+    std::filesystem::path game_folder;
+    if (p_game_folder.has_value()) {
+        game_folder = p_game_folder.value();
+    } else {
+        game_folder = file.parent_path();
+        if (const auto game_folder_name = game_folder.filename().string();
+            game_folder_name.ends_with("-UPDATE") || game_folder_name.ends_with("-patch")) {
+            // If an executable was launched from a separate update directory,
+            // use the base game directory as the game folder.
+            const std::string base_name = game_folder_name.substr(0, game_folder_name.rfind('-'));
+            const auto base_path = game_folder.parent_path() / base_name;
+            if (std::filesystem::is_directory(base_path)) {
+                game_folder = base_path;
+            }
         }
     }
 
+    std::filesystem::path eboot_name = std::filesystem::relative(file, game_folder);
+
     // Applications expect to be run from /app0 so mount the file's parent path as app0.
     auto* mnt = Common::Singleton<Core::FileSys::MntPoints>::Instance();
     mnt->Mount(game_folder, "/app0", true);
@@ -290,10 +310,11 @@ void Emulator::Run(std::filesystem::path file, const std::vector<std::string> ar
     Libraries::InitHLELibs(&linker->GetHLESymbols());
 
     // Load the module with the linker
-    const auto eboot_path = mnt->GetHostPath("/app0/" + eboot_name);
+    auto guest_eboot_path = "/app0/" + eboot_name.generic_string();
+    const auto eboot_path = mnt->GetHostPath(guest_eboot_path);
     if (linker->LoadModule(eboot_path) == -1) {
         LOG_CRITICAL(Loader, "Failed to load game's eboot.bin: {}",
-                     std::filesystem::absolute(eboot_path).string());
+                     Common::FS::PathToUTF8String(std::filesystem::absolute(eboot_path)));
         std::quick_exit(0);
     }
 
@@ -334,6 +355,7 @@ void Emulator::Run(std::filesystem::path file, const std::vector<std::string> ar
     }
 #endif
 
+    args.insert(args.begin(), eboot_name.generic_string());
     linker->Execute(args);
 
     window->InitTimers();
@@ -348,6 +370,109 @@ void Emulator::Run(std::filesystem::path file, const std::vector<std::string> ar
     std::quick_exit(0);
 }
 
+void Emulator::Restart(std::filesystem::path eboot_path,
+                       const std::vector<std::string>& guest_args) {
+    std::vector<std::string> args;
+
+    auto mnt = Common::Singleton<Core::FileSys::MntPoints>::Instance();
+    auto game_path = mnt->GetHostPath("/app0");
+
+    args.push_back("--log-append");
+    args.push_back("--game");
+    args.push_back(Common::FS::PathToUTF8String(eboot_path));
+
+    args.push_back("--override-root");
+    args.push_back(Common::FS::PathToUTF8String(game_path));
+
+    if (FileSys::MntPoints::ignore_game_patches) {
+        args.push_back("--ignore-game-patch");
+    }
+
+    if (!MemoryPatcher::patchFile.empty()) {
+        args.push_back("--patch");
+        args.push_back(MemoryPatcher::patchFile);
+    }
+
+    args.push_back("--wait-for-pid");
+    args.push_back(std::to_string(Debugger::GetCurrentPid()));
+
+    if (waitForDebuggerBeforeRun) {
+        args.push_back("--wait-for-debugger");
+    }
+
+    if (guest_args.size() > 0) {
+        args.push_back("--");
+        for (const auto& arg : guest_args) {
+            args.push_back(arg);
+        }
+    }
+
+    LOG_INFO(Common, "Restarting the emulator with args: {}", fmt::join(args, " "));
+    Libraries::SaveData::Backup::StopThread();
+    Common::Log::Denitializer();
+
+    auto& ipc = IPC::Instance();
+
+    if (ipc.IsEnabled()) {
+        ipc.SendRestart(args);
+        while (true) {
+            std::this_thread::sleep_for(std::chrono::minutes(1));
+        }
+    }
+#if defined(_WIN32)
+    std::string cmdline;
+    // Emulator executable
+    cmdline += "\"";
+    cmdline += executableName;
+    cmdline += "\"";
+    for (const auto& arg : args) {
+        cmdline += " \"";
+        cmdline += arg;
+        cmdline += "\"";
+    }
+    cmdline += "\0";
+
+    STARTUPINFOA si{};
+    si.cb = sizeof(si);
+    PROCESS_INFORMATION pi{};
+    bool success = CreateProcessA(nullptr, cmdline.data(), nullptr, nullptr, TRUE, 0, nullptr,
+                                  nullptr, &si, &pi);
+
+    if (!success) {
+        std::cerr << "Failed to restart game: {}" << GetLastError() << std::endl;
+        std::quick_exit(1);
+    }
+
+    CloseHandle(pi.hProcess);
+    CloseHandle(pi.hThread);
+#elif defined(__APPLE__) || defined(__linux__)
+    std::vector<char*> argv;
+
+    // Emulator executable
+    argv.push_back(const_cast<char*>(executableName));
+
+    for (const auto& arg : args) {
+        argv.push_back(const_cast<char*>(arg.c_str()));
+    }
+    argv.push_back(nullptr);
+
+    pid_t pid = fork();
+    if (pid == 0) {
+        // Child process - execute the new instance
+        execvp(executableName, argv.data());
+        std::cerr << "Failed to restart game: execvp failed" << std::endl;
+        std::quick_exit(1);
+    } else if (pid < 0) {
+        std::cerr << "Failed to restart game: fork failed" << std::endl;
+        std::quick_exit(1);
+    }
+#else
+#error "Unsupported platform"
+#endif
+
+    std::quick_exit(0);
+}
+
 void Emulator::LoadSystemModules(const std::string& game_serial) {
     constexpr auto ModulesToLoad = std::to_array<SysModules>(
         {{"libSceNgs2.sprx", &Libraries::Ngs2::RegisterLib},

src/emulator.h

@@ -4,6 +4,7 @@
 #pragma once
 
 #include <filesystem>
+#include <optional>
 #include <thread>
 
 #include "common/singleton.h"
@@ -25,9 +26,19 @@ public:
     Emulator();
     ~Emulator();
 
-    void Run(std::filesystem::path file, const std::vector<std::string> args = {});
+    void Run(std::filesystem::path file, std::vector<std::string> args = {},
+             std::optional<std::filesystem::path> game_folder = {});
     void UpdatePlayTime(const std::string& serial);
 
+    /**
+     * This will kill the current process and launch a new process with the same configuration
+     * (using CLI args) but replacing the eboot image and guest arguments
+     */
+    void Restart(std::filesystem::path eboot_path, const std::vector<std::string>& guest_args = {});
+
+    const char* executableName;
+    bool waitForDebuggerBeforeRun{false};
+
 private:
     void LoadSystemModules(const std::string& game_serial);
 

src/main.cpp

@@ -1,4 +1,4 @@
-// SPDX-FileCopyrightText: Copyright 2024 shadPS4 Emulator Project
+// SPDX-FileCopyrightText: Copyright 2025 shadPS4 Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
 #include "functional"
@@ -9,8 +9,10 @@
 
 #include <fmt/core.h>
 #include "common/config.h"
+#include "common/logging/backend.h"
 #include "common/memory_patcher.h"
 #include "common/path_util.h"
+#include "core/debugger.h"
 #include "core/file_sys/fs.h"
 #include "core/ipc/ipc.h"
 #include "emulator.h"
@@ -32,6 +34,10 @@ int main(int argc, char* argv[]) {
     bool has_game_argument = false;
     std::string game_path;
     std::vector<std::string> game_args{};
+    std::optional<std::filesystem::path> game_folder;
+
+    bool waitForDebugger = false;
+    std::optional<int> waitPid;
 
     // Map of argument strings to lambda functions
     std::unordered_map<std::string, std::function<void(int&)>> arg_map = {
@@ -50,6 +56,12 @@ int main(int argc, char* argv[]) {
                     "state. Does not overwrite the config file.\n"
                     "  --add-game-folder <folder>    Adds a new game folder to the config.\n"
                     "  --set-addon-folder <folder>   Sets the addon folder to the config.\n"
+                    "  --log-append                  Append log output to file instead of "
+                    "overwriting it.\n"
+                    "  --override-root <folder>      Override the game root folder. Default is the "
+                    "parent of game path\n"
+                    "  --wait-for-debugger           Wait for debugger to attach\n"
+                    "  --wait-for-pid <pid>          Wait for process with specified PID to stop\n"
                     "  -h, --help                    Display this help message\n";
              exit(0);
          }},
@@ -119,7 +131,8 @@ int main(int argc, char* argv[]) {
              std::cout << "Game folder successfully saved.\n";
              exit(0);
          }},
-        {"--set-addon-folder", [&](int& i) {
+        {"--set-addon-folder",
+         [&](int& i) {
              if (++i >= argc) {
                  std::cerr << "Error: Missing argument for --add-addon-folder\n";
                  exit(1);
@@ -136,6 +149,29 @@ int main(int argc, char* argv[]) {
              Config::save(Common::FS::GetUserPath(Common::FS::PathType::UserDir) / "config.toml");
              std::cout << "Addon folder successfully saved.\n";
              exit(0);
+         }},
+        {"--log-append", [&](int& i) { Common::Log::SetAppend(); }},
+        {"--override-root",
+         [&](int& i) {
+             if (++i >= argc) {
+                 std::cerr << "Error: Missing argument for --override-root\n";
+                 exit(1);
+             }
+             std::string folder_str{argv[i]};
+             std::filesystem::path folder{folder_str};
+             if (!std::filesystem::exists(folder) || !std::filesystem::is_directory(folder)) {
+                 std::cerr << "Error: Folder does not exist: " << folder_str << "\n";
+                 exit(1);
+             }
+             game_folder = folder;
+         }},
+        {"--wait-for-debugger", [&](int& i) { waitForDebugger = true; }},
+        {"--wait-for-pid", [&](int& i) {
+             if (++i >= argc) {
+                 std::cerr << "Error: Missing argument for --wait-for-pid\n";
+                 exit(1);
+             }
+             waitPid = std::stoi(argv[i]);
          }}};
 
     if (argc == 1) {
@@ -206,9 +242,15 @@ int main(int argc, char* argv[]) {
         }
     }
 
+    if (waitPid.has_value()) {
+        Core::Debugger::WaitForPid(waitPid.value());
+    }
+
     // Run the emulator with the resolved eboot path
-    Core::Emulator emulator;
-    emulator.Run(eboot_path, game_args);
+    Core::Emulator* emulator = Common::Singleton<Core::Emulator>::Instance();
+    emulator->executableName = argv[0];
+    emulator->waitForDebuggerBeforeRun = waitForDebugger;
+    emulator->Run(eboot_path, game_args, game_folder);
 
     return 0;
 }

src/qt_gui/main.cpp

@@ -6,7 +6,9 @@
 #include "unordered_map"
 
 #include "common/config.h"
+#include "common/logging/backend.h"
 #include "common/memory_patcher.h"
+#include "core/debugger.h"
 #include "core/file_sys/fs.h"
 #include "emulator.h"
 #include "game_install_dialog.h"
@@ -36,6 +38,10 @@ int main(int argc, char* argv[]) {
     bool show_gui = false, has_game_argument = false;
     std::string game_path;
     std::vector<std::string> game_args{};
+    std::optional<std::filesystem::path> game_folder;
+
+    bool waitForDebugger = false;
+    std::optional<int> waitPid;
 
     // Map of argument strings to lambda functions
     std::unordered_map<std::string, std::function<void(int&)>> arg_map = {
@@ -56,6 +62,12 @@ int main(int argc, char* argv[]) {
                     "  -f, --fullscreen <true|false> Specify window initial fullscreen "
                     "state. Does not overwrite the config file.\n"
                     "  --add-game-folder <folder>    Adds a new game folder to the config.\n"
+                    "  --log-append                  Append log output to file instead of "
+                    "overwriting it.\n"
+                    "  --override-root <folder>      Override the game root folder. Default is the "
+                    "parent of game path\n"
+                    "  --wait-for-debugger           Wait for debugger to attach\n"
+                    "  --wait-for-pid <pid>          Wait for process with specified PID to stop\n"
                     "  -h, --help                    Display this help message\n";
              exit(0);
          }},
@@ -129,7 +141,29 @@ int main(int argc, char* argv[]) {
              std::cout << "Game folder successfully saved.\n";
              exit(0);
          }},
-    };
+        {"--log-append", [&](int& i) { Common::Log::SetAppend(); }},
+        {"--override-root",
+         [&](int& i) {
+             if (++i >= argc) {
+                 std::cerr << "Error: Missing argument for --override-root\n";
+                 exit(1);
+             }
+             std::string folder_str{argv[i]};
+             std::filesystem::path folder{folder_str};
+             if (!std::filesystem::exists(folder) || !std::filesystem::is_directory(folder)) {
+                 std::cerr << "Error: Folder does not exist: " << folder_str << "\n";
+                 exit(1);
+             }
+             game_folder = folder;
+         }},
+        {"--wait-for-debugger", [&](int& i) { waitForDebugger = true; }},
+        {"--wait-for-pid", [&](int& i) {
+             if (++i >= argc) {
+                 std::cerr << "Error: Missing argument for --wait-for-pid\n";
+                 exit(1);
+             }
+             waitPid = std::stoi(argv[i]);
+         }}};
 
     // Parse command-line arguments using the map
     for (int i = 1; i < argc; ++i) {
@@ -181,6 +215,14 @@ int main(int argc, char* argv[]) {
         exit(1);
     }
 
+    if (waitPid.has_value()) {
+        Core::Debugger::WaitForPid(waitPid.value());
+    }
+
+    Core::Emulator* emulator = Common::Singleton<Core::Emulator>::Instance();
+    emulator->executableName = argv[0];
+    emulator->waitForDebuggerBeforeRun = waitForDebugger;
+
     // Process game path or ID if provided
     if (has_game_argument) {
         std::filesystem::path game_file_path(game_path);
@@ -204,8 +246,7 @@ int main(int argc, char* argv[]) {
         }
 
         // Run the emulator with the resolved game path
-        Core::Emulator emulator;
-        emulator.Run(game_file_path.string(), game_args);
+        emulator->Run(game_file_path.string(), game_args, game_folder);
         if (!show_gui) {
             return 0; // Exit after running the emulator without showing the GUI
         }

src/qt_gui/main_window.cpp

@@ -1225,12 +1225,12 @@ void MainWindow::StartEmulator(std::filesystem::path path) {
     isGameRunning = true;
 #ifdef __APPLE__
     // SDL on macOS requires main thread.
-    Core::Emulator emulator;
-    emulator.Run(path);
+    Core::Emulator* emulator = Common::Singleton<Core::Emulator>::Instance();
+    emulator->Run(path);
 #else
     std::thread emulator_thread([=] {
-        Core::Emulator emulator;
-        emulator.Run(path);
+        Core::Emulator* emulator = Common::Singleton<Core::Emulator>::Instance();
+        emulator->Run(path);
     });
     emulator_thread.detach();
 #endif