cheats: Use global cheat engine (#7291)

* cheats: Use global cheat engine

* cheats: Prevent wasted double-load of cheat file.

* android: Fix for cheat engine updates.

---------

Co-authored-by: GPUCode <geoster3d@gmail.com>

src/core/cheats/cheats.cpp

@@ -10,7 +10,6 @@
 #include "core/cheats/gateway_cheat.h"
 #include "core/core.h"
 #include "core/core_timing.h"
-#include "core/hle/kernel/process.h"
 
 namespace Cheats {
 
@@ -18,11 +17,11 @@ namespace Cheats {
 // we use the same value
 constexpr u64 run_interval_ticks = 50'000'000;
 
-CheatEngine::CheatEngine(u64 title_id_, Core::System& system_)
-    : system(system_), title_id{title_id_} {
-    LoadCheatFile();
+CheatEngine::CheatEngine(Core::System& system_) : system{system_} {}
+
+CheatEngine::~CheatEngine() {
     if (system.IsPoweredOn()) {
-        Connect();
+        system.CoreTiming().UnscheduleEvent(event, 0);
     }
 }
 
@@ -33,24 +32,18 @@ void CheatEngine::Connect() {
     system.CoreTiming().ScheduleEvent(run_interval_ticks, event);
 }
 
-CheatEngine::~CheatEngine() {
-    if (system.IsPoweredOn()) {
-        system.CoreTiming().UnscheduleEvent(event, 0);
-    }
-}
-
-std::vector<std::shared_ptr<CheatBase>> CheatEngine::GetCheats() const {
-    std::shared_lock<std::shared_mutex> lock(cheats_list_mutex);
+std::span<const std::shared_ptr<CheatBase>> CheatEngine::GetCheats() const {
+    std::shared_lock lock{cheats_list_mutex};
     return cheats_list;
 }
 
-void CheatEngine::AddCheat(const std::shared_ptr<CheatBase>& cheat) {
-    std::unique_lock<std::shared_mutex> lock(cheats_list_mutex);
-    cheats_list.push_back(cheat);
+void CheatEngine::AddCheat(std::shared_ptr<CheatBase>&& cheat) {
+    std::unique_lock lock{cheats_list_mutex};
+    cheats_list.push_back(std::move(cheat));
 }
 
 void CheatEngine::RemoveCheat(std::size_t index) {
-    std::unique_lock<std::shared_mutex> lock(cheats_list_mutex);
+    std::unique_lock lock{cheats_list_mutex};
     if (index < 0 || index >= cheats_list.size()) {
         LOG_ERROR(Core_Cheats, "Invalid index {}", index);
         return;
@@ -58,16 +51,16 @@ void CheatEngine::RemoveCheat(std::size_t index) {
     cheats_list.erase(cheats_list.begin() + index);
 }
 
-void CheatEngine::UpdateCheat(std::size_t index, const std::shared_ptr<CheatBase>& new_cheat) {
-    std::unique_lock<std::shared_mutex> lock(cheats_list_mutex);
+void CheatEngine::UpdateCheat(std::size_t index, std::shared_ptr<CheatBase>&& new_cheat) {
+    std::unique_lock lock{cheats_list_mutex};
     if (index < 0 || index >= cheats_list.size()) {
         LOG_ERROR(Core_Cheats, "Invalid index {}", index);
         return;
     }
-    cheats_list[index] = new_cheat;
+    cheats_list[index] = std::move(new_cheat);
 }
 
-void CheatEngine::SaveCheatFile() const {
+void CheatEngine::SaveCheatFile(u64 title_id) const {
     const std::string cheat_dir = FileUtil::GetUserPath(FileUtil::UserPath::CheatsDir);
     const std::string filepath = fmt::format("{}{:016X}.txt", cheat_dir, title_id);
 
@@ -82,7 +75,14 @@ void CheatEngine::SaveCheatFile() const {
     }
 }
 
-void CheatEngine::LoadCheatFile() {
+void CheatEngine::LoadCheatFile(u64 title_id) {
+    {
+        std::unique_lock lock{cheats_list_mutex};
+        if (loaded_title_id.has_value() && loaded_title_id == title_id) {
+            return;
+        }
+    }
+
     const std::string cheat_dir = FileUtil::GetUserPath(FileUtil::UserPath::CheatsDir);
     const std::string filepath = fmt::format("{}{:016X}.txt", cheat_dir, title_id);
 
@@ -90,20 +90,22 @@ void CheatEngine::LoadCheatFile() {
         FileUtil::CreateDir(cheat_dir);
     }
 
-    if (!FileUtil::Exists(filepath))
+    if (!FileUtil::Exists(filepath)) {
         return;
+    }
 
     auto gateway_cheats = GatewayCheat::LoadFile(filepath);
     {
-        std::unique_lock<std::shared_mutex> lock(cheats_list_mutex);
-        std::move(gateway_cheats.begin(), gateway_cheats.end(), std::back_inserter(cheats_list));
+        std::unique_lock lock{cheats_list_mutex};
+        loaded_title_id = title_id;
+        cheats_list = std::move(gateway_cheats);
     }
 }
 
 void CheatEngine::RunCallback([[maybe_unused]] std::uintptr_t user_data, s64 cycles_late) {
     {
-        std::shared_lock<std::shared_mutex> lock(cheats_list_mutex);
-        for (auto& cheat : cheats_list) {
+        std::shared_lock lock{cheats_list_mutex};
+        for (const auto& cheat : cheats_list) {
             if (cheat->IsEnabled()) {
                 cheat->Execute(system);
             }

src/core/cheats/cheats.h

@@ -5,7 +5,9 @@
 #pragma once
 
 #include <memory>
+#include <optional>
 #include <shared_mutex>
+#include <span>
 #include <vector>
 #include "common/common_types.h"
 
@@ -24,22 +26,39 @@ class CheatBase;
 
 class CheatEngine {
 public:
-    explicit CheatEngine(u64 title_id_, Core::System& system);
+    explicit CheatEngine(Core::System& system);
     ~CheatEngine();
+
+    /// Registers the cheat execution callback.
     void Connect();
-    std::vector<std::shared_ptr<CheatBase>> GetCheats() const;
-    void AddCheat(const std::shared_ptr<CheatBase>& cheat);
+
+    /// Returns a span of the currently active cheats.
+    std::span<const std::shared_ptr<CheatBase>> GetCheats() const;
+
+    /// Adds a cheat to the cheat engine.
+    void AddCheat(std::shared_ptr<CheatBase>&& cheat);
+
+    /// Removes a cheat at the specified index in the cheats list.
     void RemoveCheat(std::size_t index);
-    void UpdateCheat(std::size_t index, const std::shared_ptr<CheatBase>& new_cheat);
-    void SaveCheatFile() const;
+
+    /// Updates a cheat at the specified index in the cheats list.
+    void UpdateCheat(std::size_t index, std::shared_ptr<CheatBase>&& new_cheat);
+
+    /// Loads the cheat file from disk for the specified title id.
+    void LoadCheatFile(u64 title_id);
+
+    /// Saves currently active cheats to file for the specified title id.
+    void SaveCheatFile(u64 title_id) const;
 
 private:
-    void LoadCheatFile();
+    /// The cheat execution callback.
     void RunCallback(std::uintptr_t user_data, s64 cycles_late);
+
+private:
+    Core::System& system;
+    Core::TimingEventType* event;
+    std::optional<u64> loaded_title_id;
     std::vector<std::shared_ptr<CheatBase>> cheats_list;
     mutable std::shared_mutex cheats_list_mutex;
-    Core::TimingEventType* event;
-    Core::System& system;
-    u64 title_id;
 };
 } // namespace Cheats

src/core/cheats/gateway_cheat.cpp

@@ -472,8 +472,8 @@ std::string GatewayCheat::ToString() const {
     return result;
 }
 
-std::vector<std::unique_ptr<CheatBase>> GatewayCheat::LoadFile(const std::string& filepath) {
-    std::vector<std::unique_ptr<CheatBase>> cheats;
+std::vector<std::shared_ptr<CheatBase>> GatewayCheat::LoadFile(const std::string& filepath) {
+    std::vector<std::shared_ptr<CheatBase>> cheats;
 
     boost::iostreams::stream<boost::iostreams::file_descriptor_source> file;
     FileUtil::OpenFStream<std::ios_base::in>(file, filepath);
@@ -493,7 +493,7 @@ std::vector<std::unique_ptr<CheatBase>> GatewayCheat::LoadFile(const std::string
         line = Common::StripSpaces(line); // remove spaces at front and end
         if (line.length() >= 2 && line.front() == '[') {
             if (!cheat_lines.empty()) {
-                cheats.push_back(std::make_unique<GatewayCheat>(name, cheat_lines, comments));
+                cheats.push_back(std::make_shared<GatewayCheat>(name, cheat_lines, comments));
                 cheats.back()->SetEnabled(enabled);
                 enabled = false;
             }
@@ -511,7 +511,7 @@ std::vector<std::unique_ptr<CheatBase>> GatewayCheat::LoadFile(const std::string
         }
     }
     if (!cheat_lines.empty()) {
-        cheats.push_back(std::make_unique<GatewayCheat>(name, cheat_lines, comments));
+        cheats.push_back(std::make_shared<GatewayCheat>(name, cheat_lines, comments));
         cheats.back()->SetEnabled(enabled);
     }
     return cheats;

src/core/cheats/gateway_cheat.h

@@ -77,7 +77,7 @@ public:
     ///     (there might be multiple lines of those hex numbers)
     ///     Comment lines start with a '*'
     /// This function will pares the file for such structures
-    static std::vector<std::unique_ptr<CheatBase>> LoadFile(const std::string& filepath);
+    static std::vector<std::shared_ptr<CheatBase>> LoadFile(const std::string& filepath);
 
 private:
     std::atomic<bool> enabled = false;

src/core/core.cpp

@@ -72,7 +72,7 @@ Core::Timing& Global() {
     return System::GetInstance().CoreTiming();
 }
 
-System::System() : movie{*this} {}
+System::System() : movie{*this}, cheat_engine{*this} {}
 
 System::~System() = default;
 
@@ -320,7 +320,10 @@ System::ResultStatus System::Load(Frontend::EmuWindow& emu_window, const std::st
         LOG_ERROR(Core, "Failed to find title id for ROM (Error {})",
                   static_cast<u32>(load_result));
     }
-    cheat_engine = std::make_unique<Cheats::CheatEngine>(title_id, *this);
+
+    cheat_engine.LoadCheatFile(title_id);
+    cheat_engine.Connect();
+
     perf_stats = std::make_unique<PerfStats>(title_id);
 
     if (Settings::values.dump_textures) {
@@ -502,11 +505,11 @@ const Memory::MemorySystem& System::Memory() const {
 }
 
 Cheats::CheatEngine& System::CheatEngine() {
-    return *cheat_engine;
+    return cheat_engine;
 }
 
 const Cheats::CheatEngine& System::CheatEngine() const {
-    return *cheat_engine;
+    return cheat_engine;
 }
 
 void System::RegisterVideoDumper(std::shared_ptr<VideoDumper::Backend> dumper) {
@@ -560,7 +563,6 @@ void System::Shutdown(bool is_deserializing) {
     if (!is_deserializing) {
         GDBStub::Shutdown();
         perf_stats.reset();
-        cheat_engine.reset();
         app_loader.reset();
     }
     custom_tex_manager.reset();
@@ -718,7 +720,7 @@ void System::serialize(Archive& ar, const unsigned int file_version) {
     if (Archive::is_loading::value) {
         timing->UnlockEventQueue();
         memory->SetDSP(*dsp_core);
-        cheat_engine->Connect();
+        cheat_engine.Connect();
         gpu->Sync();
 
         // Re-register gpu callback, because gsp service changed after service_manager got

src/core/core.h

@@ -11,6 +11,7 @@
 #include <boost/serialization/version.hpp>
 #include "common/common_types.h"
 #include "core/arm/arm_interface.h"
+#include "core/cheats/cheats.h"
 #include "core/movie.h"
 #include "core/perf_stats.h"
 
@@ -48,10 +49,6 @@ struct New3dsHwCapabilities;
 enum class MemoryMode : u8;
 } // namespace Kernel
 
-namespace Cheats {
-class CheatEngine;
-}
-
 namespace VideoDumper {
 class Backend;
 }
@@ -401,7 +398,7 @@ private:
     Core::Movie movie;
 
     /// Cheats manager
-    std::unique_ptr<Cheats::CheatEngine> cheat_engine;
+    Cheats::CheatEngine cheat_engine;
 
     /// Video dumper backend
     std::shared_ptr<VideoDumper::Backend> video_dumper;