[C#] Add marshaling logic for array C# -> C conversion

diff --git a/csharp_strings.py b/csharp_strings.py
index 15be359b70c089960aebeade7cbe6577ab36f42a..c08fc2eb07e8877f23138dfc8feb8ce153b05682 100644 (file)
--- a/csharp_strings.py
+++ b/csharp_strings.py
@@ -32,11 +32,42 @@ class Consts:
         self.bindings_header = """
 using org.ldk.enums;
 using org.ldk.impl;
+using System;
 using System.Runtime.InteropServices;
 
 namespace org { namespace ldk { namespace impl {
 
 internal class bindings {
+       internal class ArrayCoder : ICustomMarshaler {
+               int size = 0;
+               GCHandle pinnedArray;
+               public static ICustomMarshaler GetInstance(string pstrCookie) {
+                       return new ArrayCoder();
+               }
+
+               public Object MarshalNativeToManaged(IntPtr pNativeData) { throw new NotImplementedException(); }
+               public IntPtr MarshalManagedToNative(Object obj) {
+                       if (obj.GetType() == typeof(byte[])) {
+                               byte[] inp = (byte[])obj;
+                               IntPtr data = Marshal.AllocHGlobal(inp.Length + 8);
+                               Marshal.WriteInt64(data, inp.Length);
+                               Marshal.Copy(inp, 0, data + 8, inp.Length);
+                               this.size = inp.Length + 8;
+                               return data;
+                       } else {
+                               throw new NotImplementedException();
+                       }
+               }
+               public void CleanUpNativeData(IntPtr pNativeData) {
+                       Marshal.FreeHGlobal(pNativeData);
+               }
+               public void CleanUpManagedData(Object ManagedObj) { }
+               public int GetNativeDataSize() {
+                       // Blindly guess based on the last allocation, no idea how else to implement this.
+                       return this.size;
+               }
+       }
+
        /*static {
                init(java.lang.Enum.class, VecOrSliceDef.class);
                init_class_cache();
@@ -1129,6 +1160,8 @@ namespace org { namespace ldk { namespace structs {
                 out_c += (", ")
             if arg_conv_info.c_ty != "void":
                 out_c += (arg_conv_info.c_ty + " " + arg_conv_info.arg_name)
+                if "[]" in arg_conv_info.java_ty:
+                    out_java += "[MarshalAs(UnmanagedType.CustomMarshaler, MarshalType=\"org.ldk.impl.ArrayCoder\")] "
                 out_java += (arg_conv_info.java_ty + " _" + arg_conv_info.arg_name) # Add a _ to avoid using reserved words
 
         out_java_struct = ""