Extended the type maps for primitive strings to C++/CLI.

Signed-off-by: Dimitar Dobrev <dpldobrev@protonmail.com>

src/Generator/Generators/CLI/CLIMarshal.cs

@@ -60,10 +60,11 @@ namespace CppSharp.Generators.CLI
                     // const char* and const char[] are the same so we can use a string
                     if (array.Type.Desugar().IsPrimitiveType(PrimitiveType.Char) &&
                         array.QualifiedType.Qualifiers.IsConst)
-                        return VisitPointerType(new PointerType
-                            {
-                                QualifiedPointee = array.QualifiedType
-                            }, quals);
+                    {
+                        var pointer = new PointerType { QualifiedPointee = array.QualifiedType };
+                        Context.ReturnType = new QualifiedType(pointer);
+                        return this.VisitPointerType(pointer, quals);
+                    }
                     goto case ArrayType.ArraySize.Variable;
 
                 case ArrayType.ArraySize.Variable:
@@ -100,13 +101,6 @@ namespace CppSharp.Generators.CLI
                 return true;
             }
 
-            if (pointer.IsConstCharString())
-            {
-                Context.Return.Write(MarshalStringToManaged(Context.ReturnVarName,
-                    pointer.Pointee.Desugar() as BuiltinType));
-                return true;
-            }
-
             PrimitiveType primitive;
             var param = Context.Parameter;
             if (param != null && (param.IsOut || param.IsInOut) &&
@@ -167,29 +161,6 @@ namespace CppSharp.Generators.CLI
             return pointer.QualifiedPointee.Visit(this);
         }
 
-        private string MarshalStringToManaged(string varName, BuiltinType type)
-        {
-            var encoding = type.Type == PrimitiveType.Char ?
-                Encoding.ASCII : Encoding.Unicode;
-
-            if (Equals(encoding, Encoding.ASCII))
-                encoding = Context.Context.Options.Encoding;
-
-            string param;
-            if (Equals(encoding, Encoding.ASCII))
-                param = "E_UTF8";
-            else if (Equals(encoding, Encoding.Unicode) ||
-                     Equals(encoding, Encoding.BigEndianUnicode))
-                param = "E_UTF16";
-            else
-                throw new NotSupportedException(string.Format("{0} is not supported yet.",
-                    Context.Context.Options.Encoding.EncodingName));
-
-            return string.Format(
-                "({0} == 0 ? nullptr : clix::marshalString<clix::{1}>({0}))",
-                varName, param);
-        }
-
         public override bool VisitMemberPointerType(MemberPointerType member,
             TypeQualifiers quals)
         {
@@ -513,18 +484,6 @@ namespace CppSharp.Generators.CLI
 
             var pointee = pointer.Pointee.Desugar();
 
-            if ((pointee.IsPrimitiveType(PrimitiveType.Char) ||
-                pointee.IsPrimitiveType(PrimitiveType.WideChar)) &&
-                pointer.QualifiedPointee.Qualifiers.IsConst)
-            {
-                Context.Before.WriteLine(
-                    "auto _{0} = clix::marshalString<clix::E_UTF8>({1});",
-                    Context.ArgName, Context.Parameter.Name);
-
-                Context.Return.Write("_{0}.c_str()", Context.ArgName);
-                return true;
-            }
-
             if (pointee is FunctionType)
             {
                 var cppTypePrinter = new CppTypePrinter();

src/Generator/Generators/CLI/CLITypePrinter.cs

@@ -107,6 +107,19 @@ namespace CppSharp.Generators.CLI
         public override TypePrinterResult VisitPointerType(PointerType pointer,
             TypeQualifiers quals)
         {
+            TypeMap typeMap;
+            if (Context.TypeMaps.FindTypeMap(pointer.Desugar(), out typeMap))
+            {
+                var typePrinterContext = new TypePrinterContext
+                {
+                    Kind = ContextKind,
+                    MarshalKind = MarshalKind,
+                    Type = pointer
+                };
+                
+                return typeMap.CLISignatureType(typePrinterContext).Visit(this);
+            }
+
             var pointee = pointer.Pointee.Desugar();
 
             if (pointee is FunctionType)
@@ -115,9 +128,6 @@ namespace CppSharp.Generators.CLI
                 return string.Format("{0}^", function.Visit(this, quals));
             }
 
-            if (pointer.IsConstCharString())
-                return "System::String^";
-
             // From http://msdn.microsoft.com/en-us/library/y31yhkeb.aspx
             // Any of the following types may be a pointer type:
             // * sbyte, byte, short, ushort, int, uint, long, ulong, char, float, double, decimal, or bool.

src/Generator/Types/Std/Stdlib.cs

@@ -90,9 +90,58 @@ namespace CppSharp.Types.Std
         }
     }
 
-    [TypeMap("const char*", GeneratorKind = GeneratorKind.CSharp)]
+    [TypeMap("const char*")]
     public class ConstCharPointer : TypeMap
     {
+        public override Type CLISignatureType(TypePrinterContext ctx)
+        {
+            return new CILType(typeof(string));
+        }
+
+        public override void CLIMarshalToNative(MarshalContext ctx)
+        {
+            ctx.Before.WriteLine(
+                "auto _{0} = clix::marshalString<clix::E_UTF8>({1});",
+                ctx.ArgName, ctx.Parameter.Name);
+
+            ctx.Return.Write("_{0}.c_str()", ctx.ArgName);
+        }
+
+        public override void CLIMarshalToManaged(MarshalContext ctx)
+        {
+            if (ctx.Parameter != null && !ctx.Parameter.IsOut &&
+                !ctx.Parameter.IsInOut)
+            {
+                ctx.Return.Write(ctx.Parameter.Name);
+                return;
+            }
+
+            Type type = ctx.ReturnType.Type.Desugar();
+            Type pointee = type.GetPointee().Desugar();
+            var isChar = type.IsPointerToPrimitiveType(PrimitiveType.Char) ||
+                (pointee.IsPointerToPrimitiveType(PrimitiveType.Char) &&
+                 ctx.Parameter != null &&
+                 (ctx.Parameter.IsInOut || ctx.Parameter.IsOut));
+            var encoding = isChar ? Encoding.ASCII : Encoding.Unicode;
+
+            if (Equals(encoding, Encoding.ASCII))
+                encoding = Context.Options.Encoding;
+
+            string param;
+            if (Equals(encoding, Encoding.ASCII))
+                param = "E_UTF8";
+            else if (Equals(encoding, Encoding.Unicode) ||
+                     Equals(encoding, Encoding.BigEndianUnicode))
+                param = "E_UTF16";
+            else
+                throw new System.NotSupportedException(
+                    $"{Context.Options.Encoding.EncodingName} is not supported yet.");
+
+            ctx.Return.Write(
+                $@"({ctx.ReturnVarName} == 0 ? nullptr : clix::marshalString<clix::{
+                    param}>({ctx.ReturnVarName}))");
+        }
+
         public override Type CSharpSignatureType(TypePrinterContext ctx)
         {
             if (ctx.Kind == TypePrinterContextKind.Managed)
@@ -178,17 +227,17 @@ namespace CppSharp.Types.Std
         }
     }
 
-    [TypeMap("const char[]", GeneratorKind = GeneratorKind.CSharp)]
+    [TypeMap("const char[]")]
     public class ConstCharArray : ConstCharPointer
     {
     }
 
-    [TypeMap("const wchar_t*", GeneratorKind = GeneratorKind.CSharp)]
+    [TypeMap("const wchar_t*")]
     public class ConstWCharTPointer : ConstCharPointer
     {
     }
 
-    [TypeMap("const char16_t*", GeneratorKind = GeneratorKind.CSharp)]
+    [TypeMap("const char16_t*")]
     public class ConstChar16TPointer : ConstCharPointer
     {
     }