2 files changed, 320 insertions, 0 deletions

diff --git a/src/core/memory/cheat_engine.cpp b/src/core/memory/cheat_engine.cpp
new file mode 100644
index 000000000..ea5c76fc0
--- /dev/null
+++ b/src/core/memory/cheat_engine.cpp
@@ -0,0 +1,234 @@
+// Copyright 2018 yuzu emulator team
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include <locale>
+#include "common/hex_util.h"
+#include "common/microprofile.h"
+#include "common/swap.h"
+#include "core/core.h"
+#include "core/core_timing.h"
+#include "core/core_timing_util.h"
+#include "core/hle/kernel/process.h"
+#include "core/hle/service/hid/controllers/npad.h"
+#include "core/hle/service/hid/hid.h"
+#include "core/hle/service/sm/sm.h"
+#include "core/memory/cheat_engine.h"
+
+namespace Memory {
+
+constexpr s64 CHEAT_ENGINE_TICKS = static_cast<s64>(Core::Timing::BASE_CLOCK_RATE / 12);
+constexpr u32 KEYPAD_BITMASK = 0x3FFFFFF;
+
+StandardVmCallbacks::StandardVmCallbacks(const Core::System& system,
+                                         const CheatProcessMetadata& metadata)
+    : system(system), metadata(metadata) {}
+
+StandardVmCallbacks::~StandardVmCallbacks() = default;
+
+void StandardVmCallbacks::MemoryRead(VAddr address, void* data, u64 size) {
+    ReadBlock(SanitizeAddress(address), data, size);
+}
+
+void StandardVmCallbacks::MemoryWrite(VAddr address, const void* data, u64 size) {
+    WriteBlock(SanitizeAddress(address), data, size);
+}
+
+u64 StandardVmCallbacks::HidKeysDown() {
+    const auto applet_resource =
+        system.ServiceManager().GetService<Service::HID::Hid>("hid")->GetAppletResource();
+    if (applet_resource == nullptr) {
+        LOG_WARNING(CheatEngine,
+                    "Attempted to read input state, but applet resource is not initialized!");
+        return false;
+    }
+
+    const auto press_state =
+        applet_resource
+            ->GetController<Service::HID::Controller_NPad>(Service::HID::HidController::NPad)
+            .GetAndResetPressState();
+    return press_state & KEYPAD_BITMASK;
+}
+
+void StandardVmCallbacks::DebugLog(u8 id, u64 value) {
+    LOG_INFO(CheatEngine, "Cheat triggered DebugLog: ID '{:01X}' Value '{:016X}'", id, value);
+}
+
+void StandardVmCallbacks::CommandLog(std::string_view data) {
+    LOG_DEBUG(CheatEngine, "[DmntCheatVm]: {}",
+              data.back() == '\n' ? data.substr(0, data.size() - 1) : data);
+}
+
+VAddr StandardVmCallbacks::SanitizeAddress(VAddr in) const {
+    if ((in < metadata.main_nso_extents.base ||
+         in >= metadata.main_nso_extents.base + metadata.main_nso_extents.size) &&
+        (in < metadata.heap_extents.base ||
+         in >= metadata.heap_extents.base + metadata.heap_extents.size)) {
+        LOG_ERROR(CheatEngine,
+                  "Cheat attempting to access memory at invalid address={:016X}, if this "
+                  "persists, "
+                  "the cheat may be incorrect. However, this may be normal early in execution if "
+                  "the game has not properly set up yet.",
+                  in);
+        return 0; ///< Invalid addresses will hard crash
+    }
+
+    return in;
+}
+
+CheatParser::~CheatParser() = default;
+
+TextCheatParser::~TextCheatParser() = default;
+
+namespace {
+template <char match>
+std::string_view ExtractName(std::string_view data, std::size_t start_index) {
+    auto end_index = start_index;
+    while (data[end_index] != match) {
+        ++end_index;
+        if (end_index > data.size() ||
+            (end_index - start_index - 1) > sizeof(CheatDefinition::readable_name)) {
+            return {};
+        }
+    }
+
+    return data.substr(start_index, end_index - start_index);
+}
+} // Anonymous namespace
+
+std::vector<CheatEntry> TextCheatParser::Parse(const Core::System& system,
+                                               std::string_view data) const {
+    std::vector<CheatEntry> out(1);
+    std::optional<u64> current_entry = std::nullopt;
+
+    for (std::size_t i = 0; i < data.size(); ++i) {
+        if (std::isspace(data[i])) {
+            continue;
+        }
+
+        if (data[i] == '{') {
+            current_entry = 0;
+
+            if (out[*current_entry].definition.num_opcodes > 0) {
+                return {};
+            }
+
+            const auto name = ExtractName<'}'>(data, i + 1);
+            if (name.empty()) {
+                return {};
+            }
+
+            std::memcpy(out[*current_entry].definition.readable_name.data(), name.data(),
+                        std::min<std::size_t>(out[*current_entry].definition.readable_name.size(),
+                                              name.size()));
+            out[*current_entry]
+                .definition.readable_name[out[*current_entry].definition.readable_name.size() - 1] =
+                '\0';
+
+            i += name.length() + 1;
+        } else if (data[i] == '[') {
+            current_entry = out.size();
+            out.emplace_back();
+
+            const auto name = ExtractName<']'>(data, i + 1);
+            if (name.empty()) {
+                return {};
+            }
+
+            std::memcpy(out[*current_entry].definition.readable_name.data(), name.data(),
+                        std::min<std::size_t>(out[*current_entry].definition.readable_name.size(),
+                                              name.size()));
+            out[*current_entry]
+                .definition.readable_name[out[*current_entry].definition.readable_name.size() - 1] =
+                '\0';
+
+            i += name.length() + 1;
+        } else if (std::isxdigit(data[i])) {
+            if (!current_entry || out[*current_entry].definition.num_opcodes >=
+                                      out[*current_entry].definition.opcodes.size()) {
+                return {};
+            }
+
+            const auto hex = std::string(data.substr(i, 8));
+            if (!std::all_of(hex.begin(), hex.end(), ::isxdigit)) {
+                return {};
+            }
+
+            out[*current_entry].definition.opcodes[out[*current_entry].definition.num_opcodes++] =
+                std::stoul(hex, nullptr, 0x10);
+
+            i += 8;
+        } else {
+            return {};
+        }
+    }
+
+    out[0].enabled = out[0].definition.num_opcodes > 0;
+    out[0].cheat_id = 0;
+
+    for (u32 i = 1; i < out.size(); ++i) {
+        out[i].enabled = out[i].definition.num_opcodes > 0;
+        out[i].cheat_id = i;
+    }
+
+    return out;
+}
+
+CheatEngine::CheatEngine(Core::System& system, std::vector<CheatEntry> cheats,
+                         const std::array<u8, 0x20>& build_id)
+    : system{system}, core_timing{system.CoreTiming()}, vm{std::make_unique<StandardVmCallbacks>(
+                                                            system, metadata)},
+      cheats(std::move(cheats)) {
+    metadata.main_nso_build_id = build_id;
+}
+
+CheatEngine::~CheatEngine() {
+    core_timing.UnscheduleEvent(event, 0);
+}
+
+void CheatEngine::Initialize() {
+    event = core_timing.RegisterEvent(
+        "CheatEngine::FrameCallback::" + Common::HexArrayToString(metadata.main_nso_build_id),
+        [this](u64 userdata, s64 cycles_late) { FrameCallback(userdata, cycles_late); });
+    core_timing.ScheduleEvent(CHEAT_ENGINE_TICKS, event);
+
+    metadata.process_id = system.CurrentProcess()->GetProcessID();
+    metadata.title_id = system.CurrentProcess()->GetTitleID();
+
+    const auto& vm_manager = system.CurrentProcess()->VMManager();
+    metadata.heap_extents = {vm_manager.GetHeapRegionBaseAddress(), vm_manager.GetHeapRegionSize()};
+    metadata.address_space_extents = {vm_manager.GetAddressSpaceBaseAddress(),
+                                      vm_manager.GetAddressSpaceSize()};
+    metadata.alias_extents = {vm_manager.GetMapRegionBaseAddress(), vm_manager.GetMapRegionSize()};
+
+    is_pending_reload.exchange(true);
+}
+
+void CheatEngine::SetMainMemoryParameters(VAddr main_region_begin, u64 main_region_size) {
+    metadata.main_nso_extents = {main_region_begin, main_region_size};
+}
+
+void CheatEngine::Reload(std::vector<CheatEntry> cheats) {
+    this->cheats = std::move(cheats);
+    is_pending_reload.exchange(true);
+}
+
+MICROPROFILE_DEFINE(Cheat_Engine, "Add-Ons", "Cheat Engine", MP_RGB(70, 200, 70));
+
+void CheatEngine::FrameCallback(u64 userdata, s64 cycles_late) {
+    if (is_pending_reload.exchange(false)) {
+        vm.LoadProgram(cheats);
+    }
+
+    if (vm.GetProgramSize() == 0) {
+        return;
+    }
+
+    MICROPROFILE_SCOPE(Cheat_Engine);
+
+    vm.Execute(metadata);
+
+    core_timing.ScheduleEvent(CHEAT_ENGINE_TICKS - cycles_late, event);
+}
+
+} // namespace Memory
diff --git a/src/core/memory/cheat_engine.h b/src/core/memory/cheat_engine.h
new file mode 100644
index 000000000..0f012e9b5
--- /dev/null
+++ b/src/core/memory/cheat_engine.h
@@ -0,0 +1,86 @@
+// Copyright 2018 yuzu emulator team
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <atomic>
+#include <vector>
+#include "common/common_types.h"
+#include "core/memory/dmnt_cheat_types.h"
+#include "core/memory/dmnt_cheat_vm.h"
+
+namespace Core {
+class System;
+}
+
+namespace Core::Timing {
+class CoreTiming;
+struct EventType;
+} // namespace Core::Timing
+
+namespace Memory {
+
+class StandardVmCallbacks : public DmntCheatVm::Callbacks {
+public:
+    StandardVmCallbacks(const Core::System& system, const CheatProcessMetadata& metadata);
+    ~StandardVmCallbacks() override;
+
+    void MemoryRead(VAddr address, void* data, u64 size) override;
+    void MemoryWrite(VAddr address, const void* data, u64 size) override;
+    u64 HidKeysDown() override;
+    void DebugLog(u8 id, u64 value) override;
+    void CommandLog(std::string_view data) override;
+
+private:
+    VAddr SanitizeAddress(VAddr address) const;
+
+    const CheatProcessMetadata& metadata;
+    const Core::System& system;
+};
+
+// Intermediary class that parses a text file or other disk format for storing cheats into a
+// CheatList object, that can be used for execution.
+class CheatParser {
+public:
+    virtual ~CheatParser();
+
+    virtual std::vector<CheatEntry> Parse(const Core::System& system,
+                                          std::string_view data) const = 0;
+};
+
+// CheatParser implementation that parses text files
+class TextCheatParser final : public CheatParser {
+public:
+    ~TextCheatParser() override;
+
+    std::vector<CheatEntry> Parse(const Core::System& system, std::string_view data) const override;
+};
+
+// Class that encapsulates a CheatList and manages its interaction with memory and CoreTiming
+class CheatEngine final {
+public:
+    CheatEngine(Core::System& system_, std::vector<CheatEntry> cheats_,
+                const std::array<u8, 0x20>& build_id);
+    ~CheatEngine();
+
+    void Initialize();
+    void SetMainMemoryParameters(VAddr main_region_begin, u64 main_region_size);
+
+    void Reload(std::vector<CheatEntry> cheats);
+
+private:
+    void FrameCallback(u64 userdata, s64 cycles_late);
+
+    DmntCheatVm vm;
+    CheatProcessMetadata metadata;
+
+    std::vector<CheatEntry> cheats;
+    std::atomic_bool is_pending_reload{false};
+
+    Core::Timing::EventType* event{};
+    Core::Timing::CoreTiming& core_timing;
+    Core::System& system;
+};
+
+} // namespace Memory