video plugins

sdk-intergration/LocalPackages/LeviathanVideo/Plugins/Core/UTF8Marshaler.cs

@@ -0,0 +1,91 @@
+/*----------------------------------------------------------------
+// Copyright (C) 2025 Beijing All rights reserved.
+//
+// Author: huachangmiao
+// Create Date: 2025/04/11
+// Module Describe:
+//----------------------------------------------------------------*/
+using System;
+using System.Runtime.InteropServices;
+using System.Text;
+
+namespace LeviathanVideo.Abstractions
+{
+
+    public class UTF8Marshaler : ICustomMarshaler
+    {
+        private static readonly UTF8Marshaler Instance = new UTF8Marshaler();
+
+        public virtual object MarshalNativeToManaged(IntPtr pNativeData) => FromNative(Encoding.UTF8, pNativeData);
+
+        public virtual IntPtr MarshalManagedToNative(object managedObj)
+        {
+            if (managedObj == null)
+                return IntPtr.Zero;
+
+            if (!(managedObj is string str))
+                throw new MarshalDirectiveException($"{GetType().Name} must be used on a string.");
+
+            return FromManaged(Encoding.UTF8, str);
+        }
+
+        public virtual void CleanUpNativeData(IntPtr pNativeData)
+        {
+            //Free anything allocated by MarshalManagedToNative
+            //This is called after the native function call completes
+
+            if (pNativeData != IntPtr.Zero)
+                Marshal.FreeHGlobal(pNativeData);
+        }
+
+        public void CleanUpManagedData(object managedObj)
+        {
+            //Free anything allocated by MarshalNativeToManaged
+            //This is called after the native function call completes
+        }
+
+        public int GetNativeDataSize() => -1; // Not a value type
+
+        public static ICustomMarshaler GetInstance(string cookie) => Instance;
+
+        public static unsafe string FromNative(Encoding encoding, IntPtr pNativeData) => FromNative(encoding, (byte*)pNativeData);
+
+        public static unsafe string FromNative(Encoding encoding, byte* pNativeData)
+        {
+            if (pNativeData == null)
+                return null;
+
+            var start = pNativeData;
+            var walk = start;
+
+            // Find the end of the string
+            while (*walk != 0) walk++;
+
+            if (walk == start)
+                return string.Empty;
+
+            return new string((sbyte*)pNativeData, 0, (int)(walk - start), encoding);
+        }
+
+        public static unsafe IntPtr FromManaged(Encoding encoding, string value)
+        {
+            if (encoding == null || value == null)
+                return IntPtr.Zero;
+
+            var length = encoding.GetByteCount(value);
+            var buffer = (byte*)Marshal.AllocHGlobal(length + 1).ToPointer();
+
+            if (length > 0)
+            {
+                fixed (char* pValue = value)
+                {
+                    encoding.GetBytes(pValue, value.Length, buffer, length);
+                }
+            }
+
+            buffer[length] = 0;
+
+            return new IntPtr(buffer);
+        }
+    }
+}