cheat_engine: Move to memory and strip VM

This is to go with the Atmosphere VM port, now it just contains the callbacks needed for the interface between DmntCheatVm and yuzu, along with the cheat parsers.

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