1 files changed, 186 insertions, 0 deletions
diff --git a/src/Ryujinx.HLE/HOS/TamperMachine.cs b/src/Ryujinx.HLE/HOS/TamperMachine.cs
new file mode 100644
index 00000000..596fc3ce
--- /dev/null
+++ b/src/Ryujinx.HLE/HOS/TamperMachine.cs
@@ -0,0 +1,186 @@
+using Ryujinx.Common.Logging;
+using Ryujinx.HLE.HOS.Kernel;
+using Ryujinx.HLE.HOS.Kernel.Process;
+using Ryujinx.HLE.HOS.Services.Hid;
+using Ryujinx.HLE.HOS.Tamper;
+using System;
+using System.Collections.Concurrent;
+using System.Collections.Generic;
+using System.Threading;
+
+namespace Ryujinx.HLE.HOS
+{
+    public class TamperMachine
+    {
+        // Atmosphere specifies a delay of 83 milliseconds between the execution of the last
+        // cheat and the re-execution of the first one.
+        private const int TamperMachineSleepMs = 1000 / 12;
+
+        private Thread _tamperThread = null;
+        private ConcurrentQueue<ITamperProgram> _programs = new ConcurrentQueue<ITamperProgram>();
+        private long _pressedKeys = 0;
+        private Dictionary<string, ITamperProgram> _programDictionary = new Dictionary<string, ITamperProgram>();
+
+        private void Activate()
+        {
+            if (_tamperThread == null || !_tamperThread.IsAlive)
+            {
+                _tamperThread = new Thread(this.TamperRunner);
+                _tamperThread.Name = "HLE.TamperMachine";
+                _tamperThread.Start();
+            }
+        }
+
+        internal void InstallAtmosphereCheat(string name, string buildId, IEnumerable<string> rawInstructions, ProcessTamperInfo info, ulong exeAddress)
+        {
+            if (!CanInstallOnPid(info.Process.Pid))
+            {
+                return;
+            }
+
+            ITamperedProcess tamperedProcess = new TamperedKProcess(info.Process);
+            AtmosphereCompiler compiler = new AtmosphereCompiler(exeAddress, info.HeapAddress, info.AliasAddress, info.AslrAddress, tamperedProcess);
+            ITamperProgram program = compiler.Compile(name, rawInstructions);
+
+            if (program != null)
+            {
+                program.TampersCodeMemory = false;
+
+                _programs.Enqueue(program);
+                _programDictionary.TryAdd($"{buildId}-{name}", program);
+            }
+
+            Activate();
+        }
+
+        private bool CanInstallOnPid(ulong pid)
+        {
+            // Do not allow tampering of kernel processes.
+            if (pid < KernelConstants.InitialProcessId)
+            {
+                Logger.Warning?.Print(LogClass.TamperMachine, $"Refusing to tamper kernel process {pid}");
+
+                return false;
+            }
+
+            return true;
+        }
+
+        public void EnableCheats(string[] enabledCheats)
+        {
+            foreach (var program in _programDictionary.Values)
+            {
+                program.IsEnabled = false;
+            }
+
+            foreach (var cheat in enabledCheats)
+            {
+                if (_programDictionary.TryGetValue(cheat, out var program))
+                {
+                    program.IsEnabled = true;
+                }
+            }
+        }
+
+        private bool IsProcessValid(ITamperedProcess process)
+        {
+            return process.State != ProcessState.Crashed && process.State != ProcessState.Exiting && process.State != ProcessState.Exited;
+        }
+
+        private void TamperRunner()
+        {
+            Logger.Info?.Print(LogClass.TamperMachine, "TamperMachine thread running");
+
+            int sleepCounter = 0;
+
+            while (true)
+            {
+                // Sleep to not consume too much CPU.
+                if (sleepCounter == 0)
+                {
+                    sleepCounter = _programs.Count;
+                    Thread.Sleep(TamperMachineSleepMs);
+                }
+                else
+                {
+                    sleepCounter--;
+                }
+
+                if (!AdvanceTamperingsQueue())
+                {
+                    // No more work to be done.
+
+                    Logger.Info?.Print(LogClass.TamperMachine, "TamperMachine thread exiting");
+
+                    return;
+                }
+            }
+        }
+
+        private bool AdvanceTamperingsQueue()
+        {
+            if (!_programs.TryDequeue(out ITamperProgram program))
+            {
+                // No more programs in the queue.
+                _programDictionary.Clear();
+
+                return false;
+            }
+
+            // Check if the process is still suitable for running the tamper program.
+            if (!IsProcessValid(program.Process))
+            {
+                // Exit without re-enqueuing the program because the process is no longer valid.
+                return true;
+            }
+
+            // Re-enqueue the tampering program because the process is still valid.
+            _programs.Enqueue(program);
+
+            Logger.Debug?.Print(LogClass.TamperMachine, $"Running tampering program {program.Name}");
+
+            try
+            {
+                ControllerKeys pressedKeys = (ControllerKeys)Thread.VolatileRead(ref _pressedKeys);
+                program.Process.TamperedCodeMemory = false;
+                program.Execute(pressedKeys);
+
+                // Detect the first attempt to tamper memory and log it.
+                if (!program.TampersCodeMemory && program.Process.TamperedCodeMemory)
+                {
+                    program.TampersCodeMemory = true;
+
+                    Logger.Warning?.Print(LogClass.TamperMachine, $"Tampering program {program.Name} modifies code memory so it may not work properly");
+                }
+            }
+            catch (Exception ex)
+            {
+                Logger.Debug?.Print(LogClass.TamperMachine, $"The tampering program {program.Name} crashed, this can happen while the game is starting");
+
+                if (!string.IsNullOrEmpty(ex.Message))
+                {
+                    Logger.Debug?.Print(LogClass.TamperMachine, ex.Message);
+                }
+            }
+
+            return true;
+        }
+
+        public void UpdateInput(List<GamepadInput> gamepadInputs)
+        {
+            // Look for the input of the player one or the handheld.
+            foreach (GamepadInput input in gamepadInputs)
+            {
+                if (input.PlayerId == PlayerIndex.Player1 || input.PlayerId == PlayerIndex.Handheld)
+                {
+                    Thread.VolatileWrite(ref _pressedKeys, (long)input.Buttons);
+
+                    return;
+                }
+            }
+
+            // Clear the input because player one is not conected.
+            Thread.VolatileWrite(ref _pressedKeys, 0);
+        }
+    }
+}