update MemoryPatch

Author: qstage

FixRandomSpawn.csproj

@@ -8,7 +8,7 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="CounterStrikeSharp.API" Version="1.0.303" />
+    <PackageReference Include="CounterStrikeSharp.API" Version="1.0.305" />
   </ItemGroup>
 
 </Project>

Plugin/GameRules.cs

@@ -15,7 +15,7 @@ public void Init(bool hotReload, Plugin plugin)
 
         plugin.RegisterListener<Listeners.OnMapStart>(manName =>
         {
-            Server.NextFrame(() =>
+            Server.NextWorldUpdate(() =>
             {
                 FindGameRules();
             });

Plugin/MemoryPatch.cs

@@ -5,7 +5,7 @@
 
 namespace FixRandomSpawn;
 
-public unsafe partial class MemoryPatch
+public unsafe partial class MemoryPatch(string? modulePath = null)
 {
     [LibraryImport("libc", EntryPoint = "mprotect")]
     private static partial int MProtect(nint address, int len, int protect);
@@ -14,15 +14,24 @@ public unsafe partial class MemoryPatch
     [return: MarshalAs(UnmanagedType.Bool)]
     private unsafe static partial bool VirtualProtect(nint address, int dwSize, int newProtect, int* oldProtect);
 
+    private readonly string modulePath_ = modulePath ?? Addresses.ServerPath;
     private readonly Dictionary<int, List<byte>> oldPattern_ = [];
-    private readonly string modulePath_;
     private nint addr_;
 
-    public MemoryPatch(string? modulePath = null)
+    private enum MemoryAccess
     {
-        modulePath_ = modulePath ?? Addresses.ServerPath;
+        Read = 1,
+        Write,
+        Exec = 4
     }
 
+    private const int PAGE_READONLY = 0x2;
+    private const int PAGE_READWRITE = 0x4;
+    private const int PAGE_EXECUTE_READ = 0x20;
+    private const int PAGE_EXECUTE_READWRITE = 0x40;
+
+    private const int PAGESIZE = 4096;
+
     public void Init(string signature)
     {
         addr_ = NativeAPI.FindSignature(modulePath_, signature);
@@ -33,15 +42,14 @@ public void Apply(string patchSignature, int offset = 0)
         if (string.IsNullOrEmpty(patchSignature) || oldPattern_.ContainsKey(offset)) return;
 
         byte[] bytes = [.. patchSignature.Split(' ').Select(b => byte.Parse(b, NumberStyles.HexNumber))];
-        byte* ptrAddr = GetPtr<byte>(offset);
+        oldPattern_[offset] = [];
 
-        SetMemAccess(ptrAddr, bytes.Length);
+        byte* ptrAddr = GetPtr<byte>(offset);
+        SetMemAccess(ptrAddr, bytes.Length, MemoryAccess.Read | MemoryAccess.Write | MemoryAccess.Exec);
 
         for (int i = 0; i < bytes.Length; i++)
         {
-            oldPattern_[offset] = [];
             oldPattern_[offset].Add(ptrAddr[i]);
-            
             ptrAddr[i] = bytes[i];
         }
     }
@@ -53,31 +61,62 @@ public void Restore()
         foreach (var (offset, pattern) in oldPattern_)
         {
             byte* ptrAddr = GetPtr<byte>(offset);
+            SetMemAccess(ptrAddr, pattern.Count, MemoryAccess.Read | MemoryAccess.Write | MemoryAccess.Exec);
 
             for (int i = 0; i < pattern.Count; i++)
             {
                 ptrAddr[i] = pattern[i];
             }
+
+            oldPattern_.Remove(offset);
         }
     }
 
-    private T* GetPtr<T>(int offset = 0) where T: unmanaged => (T*)(addr_ + offset);
+    public void Write<T>(T data, int offset = 0) where T: unmanaged
+    {
+        T* ptrAddr = GetPtr<T>(offset);
+        SetMemAccess(ptrAddr, sizeof(T), MemoryAccess.Write | MemoryAccess.Read | MemoryAccess.Exec);
+
+        *ptrAddr = data;
+    }
+
+    public T Read<T>(int offset = 0) where T: unmanaged
+    {
+        T* ptrAddr = GetPtr<T>(offset);
+        SetMemAccess(ptrAddr, sizeof(T), MemoryAccess.Read | MemoryAccess.Exec);
+
+        return *ptrAddr;
+    }
+
+    private T* GetPtr<T>(int offset = 0) where T: unmanaged
+    {
+        return (T*)(addr_ + offset);
+    }
 
-    private bool SetMemAccess<T>(T* ptrAddr, int size) where T: unmanaged
+    private bool SetMemAccess<T>(T* ptrAddr, int size, MemoryAccess access) where T: unmanaged
     {
         nint addr = (nint)ptrAddr;
 
         if (addr == nint.Zero)
             throw new ArgumentNullException(nameof(ptrAddr));
 
-        const int PAGESIZE = 4096;
-
         nint LALIGN(nint addr) => addr & ~(PAGESIZE-1);
         int LALDIF(nint addr) => (int)(addr % PAGESIZE);
 
+        if (RuntimeInformation.IsOSPlatform(OSPlatform.Linux))
+        {
+            return MProtect(LALIGN(addr), size + LALDIF(addr), (int)access) == 0;
+        }
+
         int* oldProtect = stackalloc int[1];
+        int prot = access switch
+        {
+            MemoryAccess.Read => PAGE_READONLY,
+            MemoryAccess.Write => PAGE_READWRITE,
+            MemoryAccess.Exec => PAGE_EXECUTE_READ,
+            _ => PAGE_EXECUTE_READWRITE
+        };
 
-        return RuntimeInformation.IsOSPlatform(OSPlatform.Linux) ? 
-            MProtect(LALIGN(addr), size + LALDIF(addr), 7) == 0 : VirtualProtect(addr, size, 0x40, oldProtect);
+        return VirtualProtect(addr, size, prot, oldProtect);
     }
-} 
+}

Plugin/Plugin.cs

@@ -1,11 +1,13 @@
 using CounterStrikeSharp.API.Core;
+using CounterStrikeSharp.API.Core.Attributes;
 
 namespace FixRandomSpawn;
 
+[MinimumApiVersion(305)]
 public sealed partial class Plugin : BasePlugin
 {
     public override string ModuleName { get; } = "FixRandomSpawn";
-    public override string ModuleVersion { get; } = "1.1.0";
+    public override string ModuleVersion { get; } = "1.1.2";
     public override string ModuleAuthor { get; } = "xstage";
 
     private readonly GameRules gameRules_ = new GameRules();