Added type maps for primitive strings (pointers to char).

const char*, const char16_t* and const wchar_t* in particular.

This enables comparison of types when resolving ambiguity.

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

src/AST/CppTypePrinter.cs

@@ -181,7 +181,7 @@ namespace CppSharp.AST
         {
             FunctionType func;
             if (ResolveTypedefs && !typedef.Declaration.Type.IsPointerTo(out func))
-                return typedef.Declaration.Type.Visit(this);
+                return typedef.Declaration.Type.Visit(this, quals);
             var qual = GetStringQuals(quals);
             return $"{qual}{typedef.Declaration.Visit(this)}";
         }

src/Generator/Generators/CSharp/CSharpMarshal.cs

@@ -46,8 +46,6 @@ namespace CppSharp.Generators.CSharp
             typePrinter = new CSharpTypePrinter(context.Context);
         }
 
-        public bool MarshalsParameter { get; set; }
-
         public override bool VisitType(Type type, TypeQualifiers quals)
         {
             TypeMap typeMap;
@@ -132,10 +130,11 @@ namespace CppSharp.Generators.CSharp
                     // 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);
+                    }
                     MarshalArray(array);
                     break;
                 case ArrayType.ArraySize.Variable:
@@ -155,20 +154,13 @@ namespace CppSharp.Generators.CSharp
             var isRefParam = param != null && (param.IsInOut || param.IsOut);
 
             var pointee = pointer.Pointee.Desugar();
-            bool marshalPointeeAsString = pointee.IsConstCharString() && isRefParam;
-
-            if ((pointer.IsConstCharString() && !MarshalsParameter) ||
-                marshalPointeeAsString)
-            {
-                Context.Return.Write(MarshalStringToManaged(Context.ReturnVarName,
-                    pointer.GetFinalPointee().Desugar() as BuiltinType));
-                return true;
-            }
-
-            var finalPointee = pointer.GetFinalPointee();
+            var finalPointee = pointer.GetFinalPointee().Desugar();
             PrimitiveType primitive;
-            if (finalPointee.IsPrimitiveType(out primitive) || finalPointee.IsEnumType())
-            {
+            if ((pointee.IsConstCharString() && isRefParam) ||
+                (!finalPointee.IsPrimitiveType(out primitive) &&
+                 !finalPointee.IsEnumType()))
+                return pointer.QualifiedPointee.Visit(this);
+
             if (isRefParam)
             {
                 Context.Return.Write("_{0}", param.Name);
@@ -203,33 +195,6 @@ namespace CppSharp.Generators.CSharp
             return true;
         }
 
-            return pointer.QualifiedPointee.Visit(this);
-        }
-
-        private string MarshalStringToManaged(string varName, BuiltinType type)
-        {
-            var isChar = type.Type == PrimitiveType.Char;
-            var encoding = isChar ? Encoding.ASCII : Encoding.Unicode;
-
-            if (Equals(encoding, Encoding.ASCII))
-                encoding = Context.Context.Options.Encoding;
-
-            if (Equals(encoding, Encoding.ASCII))
-                return $"Marshal.PtrToStringAnsi({varName})";
-
-            if (Equals(encoding, Encoding.UTF8))
-                return $"Marshal.PtrToStringUTF8({varName})";
-
-            // If we reach this, we know the string is Unicode.
-            if (type.Type == PrimitiveType.Char ||
-                Context.Context.TargetInfo.WCharWidth == 16)
-                return $"Marshal.PtrToStringUni({varName})";
-
-            // If we reach this, we should have an UTF-32 wide string.
-            const string encodingName = "System.Text.Encoding.UTF32";
-            return $"CppSharp.Runtime.Helpers.MarshalEncodedString({varName}, {encodingName})";
-        }
-
         public override bool VisitPrimitiveType(PrimitiveType primitive, TypeQualifiers quals)
         {
             switch (primitive)
@@ -377,11 +342,11 @@ namespace CppSharp.Generators.CSharp
                 if (dtor != null && dtor.IsVirtual)
                 {
                     Context.Before.WriteLine("else {0}{1} = ({2}) {3}.{4}({5}{6});",
-                        MarshalsParameter
+                        Context.Parameter != null
                             ? string.Empty
                             : string.Format("{0}.NativeToManagedMap[{1}] = ", qualifiedClass, Context.ReturnVarName),
                         ret, qualifiedIdentifier, qualifiedClass, Helpers.CreateInstanceIdentifier, Context.ReturnVarName,
-                        MarshalsParameter ? ", skipVTables: true" : string.Empty);
+                        Context.Parameter != null ? ", skipVTables: true" : string.Empty);
                 }
                 else
                 {
@@ -554,7 +519,6 @@ namespace CppSharp.Generators.CSharp
             if (templateSubstitution != null)
                 realPointer = templateSubstitution.Replacement.Type.Desugar() as PointerType;
             realPointer = realPointer ?? pointer;
-            var pointee = pointer.Pointee.Desugar();
             if (Context.Function != null &&
                 (realPointer.IsPrimitiveTypeConvertibleToRef() ||
                  (templateSubstitution != null && realPointer.Pointee.IsEnumType())) &&
@@ -597,23 +561,20 @@ namespace CppSharp.Generators.CSharp
             var param = Context.Parameter;
             var isRefParam = param != null && (param.IsInOut || param.IsOut);
 
+            var pointee = pointer.Pointee.Desugar();
             if (pointee.IsConstCharString() && isRefParam)
             {
                 if (param.IsOut)
                 {
                     Context.Return.Write("IntPtr.Zero");
                     Context.ArgumentPrefix.Write("&");
+                    return true;
                 }
-                else if (param.IsInOut)
-                {
-                    Context.Return.Write(MarshalStringToUnmanaged(Context.Parameter.Name));
+                pointer.QualifiedPointee.Visit(this);
+                if (param.IsInOut)
                     Context.ArgumentPrefix.Write("&");
-                }
                 else
-                {
-                    Context.Return.Write(MarshalStringToUnmanaged(Context.Parameter.Name));
                     Context.Cleanup.WriteLine("Marshal.FreeHGlobal({0});", Context.ArgName);
-                }
                 return true;
             }
 
@@ -643,11 +604,9 @@ namespace CppSharp.Generators.CSharp
                 return true;
             }
 
-            var marshalAsString = pointer.IsConstCharString();
             var finalPointee = pointer.GetFinalPointee();
             PrimitiveType primitive;
-            if (finalPointee.IsPrimitiveType(out primitive) || finalPointee.IsEnumType() ||
-                marshalAsString)
+            if (finalPointee.IsPrimitiveType(out primitive) || finalPointee.IsEnumType())
             {
                 // From MSDN: "note that a ref or out parameter is classified as a moveable
                 // variable". This means we must create a local variable to hold the result
@@ -670,24 +629,14 @@ namespace CppSharp.Generators.CSharp
                 }
                 else
                 {
-                    if (!marshalAsString &&
-                        Context.Context.Options.MarshalCharAsManagedChar &&
+                    if (Context.Context.Options.MarshalCharAsManagedChar &&
                         primitive == PrimitiveType.Char)
                         Context.Return.Write($"({typePrinter.PrintNative(pointer)}) ");
 
-                    if (marshalAsString && (Context.MarshalKind == MarshalKind.NativeField ||
-                        Context.MarshalKind == MarshalKind.VTableReturnValue ||
-                        Context.MarshalKind == MarshalKind.Variable))
-                    {
-                        Context.Return.Write(MarshalStringToUnmanaged(Context.Parameter.Name));
-                    }
-                    else
-                    {
                     if (qualifiedPointer.IsConstRefToPrimitive())
                         Context.Return.Write("&");
                     Context.Return.Write(Context.Parameter.Name);
                 }
-                }
 
                 return true;
             }
@@ -695,21 +644,6 @@ namespace CppSharp.Generators.CSharp
             return pointer.QualifiedPointee.Visit(this);
         }
 
-        private string MarshalStringToUnmanaged(string varName)
-        {
-            if (Equals(Context.Context.Options.Encoding, Encoding.ASCII))
-            {
-                return string.Format("Marshal.StringToHGlobalAnsi({0})", varName);
-            }
-            if (Equals(Context.Context.Options.Encoding, Encoding.Unicode) ||
-                Equals(Context.Context.Options.Encoding, Encoding.BigEndianUnicode))
-            {
-                return string.Format("Marshal.StringToHGlobalUni({0})", varName);
-            }
-            throw new NotSupportedException(string.Format("{0} is not supported yet.",
-                Context.Context.Options.Encoding.EncodingName));
-        }
-
         public override bool VisitPrimitiveType(PrimitiveType primitive, TypeQualifiers quals)
         {
             switch (primitive)

src/Generator/Generators/CSharp/CSharpSources.cs

@@ -927,12 +927,12 @@ namespace CppSharp.Generators.CSharp
                 if (type.IsPointer())
                 {
                     Type pointee = type.GetFinalPointee();
-                    if (pointee.IsPrimitiveType() && !type.IsConstCharString())
+                    if (pointee.IsPrimitiveType())
                     {
                         Write($"({CSharpTypePrinter.IntPtrType}) ");
                         var templateSubstitution = pointee.Desugar(false) as TemplateParameterSubstitutionType;
                         if (templateSubstitution != null)
-                            Write($"(object) ");
+                            Write("(object) ");
                     }
                 }
                 WriteLine($"{marshal.Context.Return};");
@@ -1672,11 +1672,12 @@ namespace CppSharp.Generators.CSharp
                 {
                     ReturnType = param.QualifiedType,
                     ReturnVarName = param.Name,
-                    ParameterIndex = i
+                    ParameterIndex = i,
+                    Parameter = param
                 };
 
                 ctx.PushMarshalKind(MarshalKind.GenericDelegate);
-                var marshal = new CSharpMarshalNativeToManagedPrinter(ctx) { MarshalsParameter = true };
+                var marshal = new CSharpMarshalNativeToManagedPrinter(ctx);
                 param.Visit(marshal);
                 ctx.PopMarshalKind();
 

src/Generator/Generators/CSharp/CSharpTypePrinter.cs

@@ -184,16 +184,16 @@ namespace CppSharp.Generators.CSharp
 
             if (allowStrings && pointer.IsConstCharString())
             {
-                if (isManagedContext)
-                    return "string";
-                if (Parameter == null || Parameter.Name == Helpers.ReturnIdentifier)
-                    return IntPtrType;
-                if (Options.Encoding == Encoding.ASCII)
-                    return string.Format("[MarshalAs(UnmanagedType.LPStr)] string");
-                if (Options.Encoding == Encoding.Unicode ||
-                    Options.Encoding == Encoding.BigEndianUnicode)
-                    return string.Format("[MarshalAs(UnmanagedType.LPWStr)] string");
-                throw new NotSupportedException($"{Options.Encoding.EncodingName} is not supported yet.");
+                TypeMap typeMap;
+                TypeMapDatabase.FindTypeMap(pointer, out typeMap);
+                var typePrinterContext = new TypePrinterContext()
+                {
+                    Kind = Kind,
+                    MarshalKind = MarshalKind,
+                    Type = pointer.Pointee,
+                    Parameter = Parameter
+                };
+                return typeMap.CSharpSignatureType(typePrinterContext).Visit(this);
             }
 
             var pointee = pointer.Pointee.Desugar();

src/Generator/Types/Std/Stdlib.cs

@@ -1,5 +1,6 @@
 using System.Collections.Generic;
 using System.Linq;
+using System.Text;
 using CppSharp.AST;
 using CppSharp.AST.Extensions;
 using CppSharp.Generators;
@@ -81,6 +82,109 @@ namespace CppSharp.Types.Std
         }
     }
 
+    [TypeMap("const char*", GeneratorKind = GeneratorKind.CSharp)]
+    public class ConstCharPointer : TypeMap
+    {
+        public override Type CSharpSignatureType(TypePrinterContext ctx)
+        {
+            if (ctx.Kind == TypePrinterContextKind.Managed)
+                return new CILType(typeof(string));
+
+            if (ctx.Parameter == null || ctx.Parameter.Name == Helpers.ReturnIdentifier)
+                return new CustomType(CSharpTypePrinter.IntPtrType);
+            if (Options.Encoding == Encoding.ASCII)
+                return new CustomType("[MarshalAs(UnmanagedType.LPStr)] string");
+            if (Options.Encoding == Encoding.Unicode ||
+                Options.Encoding == Encoding.BigEndianUnicode)
+                return new CustomType("[MarshalAs(UnmanagedType.LPWStr)] string");
+            throw new System.NotSupportedException(
+                $"{Options.Encoding.EncodingName} is not supported yet.");
+        }
+
+        public override void CSharpMarshalToNative(CSharpMarshalContext ctx)
+        {
+            if (ctx.Parameter.Usage == ParameterUsage.Unknown &&
+                ctx.MarshalKind != MarshalKind.NativeField &&
+                ctx.MarshalKind != MarshalKind.VTableReturnValue &&
+                ctx.MarshalKind != MarshalKind.Variable)
+            {
+                ctx.Return.Write(ctx.Parameter.Name);
+                return;
+            }
+            if (Equals(Options.Encoding, Encoding.ASCII))
+            {
+                ctx.Return.Write($"Marshal.StringToHGlobalAnsi({ctx.Parameter.Name})");
+                return;
+            }
+            if (Equals(Options.Encoding, Encoding.Unicode) ||
+                Equals(Options.Encoding, Encoding.BigEndianUnicode))
+            {
+                ctx.Return.Write($"Marshal.StringToHGlobalUni({ctx.Parameter.Name})");
+                return;
+            }
+            throw new System.NotSupportedException(
+                $"{Options.Encoding.EncodingName} is not supported yet.");
+        }
+
+        public override void CSharpMarshalToManaged(CSharpMarshalContext ctx)
+        {
+            if (ctx.Parameter != null && !ctx.Parameter.IsOut &&
+                !ctx.Parameter.IsInOut)
+            {
+                ctx.Return.Write(ctx.Parameter.Name);
+                return;
+            }
+
+            Type type = ctx.ReturnType.Type.Desugar();
+            Type pointee = type.GetPointee().Desugar();
+            var isChar = type.IsPointerToPrimitiveType(PrimitiveType.Char) ||
+                (pointee.IsPointerToPrimitiveType(PrimitiveType.Char) &&
+                 ctx.Parameter != null &&
+                 (ctx.Parameter.IsInOut || ctx.Parameter.IsOut));
+            var encoding = isChar ? Encoding.ASCII : Encoding.Unicode;
+
+            if (Equals(encoding, Encoding.ASCII))
+                encoding = Options.Encoding;
+
+            if (Equals(encoding, Encoding.ASCII))
+            {
+                ctx.Return.Write($"Marshal.PtrToStringAnsi({ctx.ReturnVarName})");
+                return;
+            }
+            if (Equals(encoding, Encoding.UTF8))
+            {
+                ctx.Return.Write($"Marshal.PtrToStringUTF8({ctx.ReturnVarName})");
+                return;
+            }
+
+            // If we reach this, we know the string is Unicode.
+            if (isChar || ctx.Context.TargetInfo.WCharWidth == 16)
+            {
+                ctx.Return.Write($"Marshal.PtrToStringUni({ctx.ReturnVarName})");
+                return;
+            }
+            // If we reach this, we should have an UTF-32 wide string.
+            const string encodingName = "System.Text.Encoding.UTF32";
+            ctx.Return.Write($@"CppSharp.Runtime.Helpers.MarshalEncodedString({
+                ctx.ReturnVarName}, {encodingName})");
+        }
+    }
+
+    [TypeMap("const char[]", GeneratorKind = GeneratorKind.CSharp)]
+    public class ConstCharArray : ConstCharPointer
+    {
+    }
+
+    [TypeMap("const wchar_t*", GeneratorKind = GeneratorKind.CSharp)]
+    public class ConstWCharTPointer : ConstCharPointer
+    {
+    }
+
+    [TypeMap("const char16_t*", GeneratorKind = GeneratorKind.CSharp)]
+    public class ConstChar16TPointer : ConstCharPointer
+    {
+    }
+
     [TypeMap("basic_string<char, char_traits<char>, allocator<char>>")]
     public class String : TypeMap
     {

src/Generator/Types/TypeMapDatabase.cs

@@ -110,16 +110,6 @@ namespace CppSharp.Types
                 return typeMap.IsEnabled;
             }
 
-            Type desugared = type.Desugar();
-            bool printExtra = desugared.GetPointee() != null &&
-                desugared.GetFinalPointee().Desugar().IsPrimitiveType();
-            var typePrinter = new CppTypePrinter
-            {
-                PrintTypeQualifiers = printExtra,
-                PrintTypeModifiers = printExtra,
-                PrintLogicalNames = true
-            };
-
             var template = type as TemplateSpecializationType;
             if (template != null)
             {
@@ -131,22 +121,31 @@ namespace CppSharp.Types
                         out typeMap);
             }
 
-            typePrinter.PrintScopeKind = TypePrintScopeKind.Local;
-            if (FindTypeMap(type.Visit(typePrinter), out typeMap))
+            Type desugared = type.Desugar();
+            bool printExtra = desugared.GetPointee() != null &&
+                desugared.GetFinalPointee().Desugar().IsPrimitiveType();
+            var typePrinter = new CppTypePrinter
             {
-                typeMap.Type = type;
-                typeMaps[type] = typeMap;
-                return true;
-            }
+                PrintTypeQualifiers = printExtra,
+                PrintTypeModifiers = printExtra,
+                PrintLogicalNames = true
+            };
 
-            typePrinter.PrintScopeKind = TypePrintScopeKind.Qualified;
+            foreach (var resolveTypeDefs in new[] { true, false })
+                foreach (var typePrintScopeKind in
+                    new[] { TypePrintScopeKind.Local, TypePrintScopeKind.Qualified })
+                {
+                    typePrinter.ResolveTypedefs = resolveTypeDefs;
+                    typePrinter.PrintScopeKind = typePrintScopeKind;
                     if (FindTypeMap(type.Visit(typePrinter), out typeMap))
                     {
                         typeMap.Type = type;
                         typeMaps[type] = typeMap;
                         return true;
                     }
+                }
 
+            typeMap = null;
             var typedef = type as TypedefType;
             return typedef != null && FindTypeMap(typedef.Declaration, type, out typeMap);
         }

tests/CSharp/CSharp.cpp

@@ -2,6 +2,10 @@
 
 #include "CSharp.h"
 
+Foo::Foo(const QString& name)
+{
+}
+
 Foo::Foo(const char* name) : publicFieldMappedToEnum(TestFlag::Flag2)
 {
     A = 10;

tests/CSharp/CSharp.cs

@@ -243,6 +243,25 @@ namespace CppSharp.Tests
         }
     }
 
+    [TypeMap("QString")]
+    public class QString : TypeMap
+    {
+        public override Type CSharpSignatureType(TypePrinterContext ctx)
+        {
+            return new CILType(typeof(string));
+        }
+
+        public override void CSharpMarshalToNative(CSharpMarshalContext ctx)
+        {
+            ctx.Return.Write("\"test\"");
+        }
+
+        public override void CSharpMarshalToManaged(CSharpMarshalContext ctx)
+        {
+            ctx.Return.Write("\"test\"");
+        }
+    }
+
     #endregion
 }
 

tests/CSharp/CSharp.h

@@ -8,9 +8,14 @@
 #include "AnotherUnit.h"
 #include "CSharpTemplates.h"
 
+class DLL_API QString
+{
+};
+
 class DLL_API Foo
 {
 public:
+    Foo(const QString& name);
     Foo(const char* name = 0);
     Foo(int a, int p = 0);
     Foo(char16_t ch);