public static void ParameterInitMiddleware(ref IMarshalContext ctx, Action next)
{
for (int index = 0; index < ctx.MethodSymbol.Parameters.Length; index++)
{
var symbol = ctx.MethodSymbol.Parameters[index];
var id = ctx.DeclareVariable(symbol.Type);
ctx.SetVariable(id, _ => IdentifierName(FormatName(symbol.Name)));
ctx.SetParameterToVariable(index, id);
}
next();
}
public static void GenericPointerMarshaller(ref IMarshalContext ctx, Action next)
{
for (int i = 0; i < ctx.LoadTypes.Length - 1; i++)
{
var lt = ctx.LoadTypes[i];
if (lt is IPointerTypeSymbol pts)
{
if (pts.PointedAtType is ITypeParameterSymbol tps)
{
var id = ctx.DeclareVariable
(
ctx.Compilation.CreatePointerTypeSymbol
(ctx.Compilation.GetSpecialType(SpecialType.System_Void))
);
var baseId = ctx.ParameterVariables[i];
ctx.SetVariable(id, ctx => CastExpression(IdentifierName("void*"), ctx.ResolveVariable(baseId).Value));
ctx.SetParameterToVariable(i, id);
}
}
}
next();
}
public static void DelegateMarshaller(ref IMarshalContext ctx, Action next)
{
for (var index = 0; index < ctx.ParameterVariables.Length; index++)
{
var options = ctx.ParameterMarshalOptions[index];
if (ctx.LoadTypes[index].TypeKind != TypeKind.Delegate)
{
continue;
}
ctx.LoadTypes[index] = ctx.Compilation.GetSpecialType(SpecialType.System_IntPtr);
var id = ctx.DeclareVariable(ctx.LoadTypes[index]);
var parameterVariable = ctx.ResolveVariable(ctx.ParameterVariables[index]);
ctx.SetVariable
(
id, ctx => ConditionalExpression
(
BinaryExpression
(
SyntaxKind.EqualsExpression, parameterVariable.Value,
LiteralExpression(SyntaxKind.NullLiteralExpression)
),
MemberAccessExpression
(
SyntaxKind.SimpleMemberAccessExpression, IdentifierName(nameof(IntPtr)),
IdentifierName(nameof(IntPtr.Zero))
), InvocationExpression
( // System.Runtime.InteropServices.Marshal.GetDelegateForFunctionPointer<T>(ResultName)
MemberAccessExpression
(
SyntaxKind.SimpleMemberAccessExpression,
MemberAccessExpression
(
SyntaxKind.SimpleMemberAccessExpression,
MemberAccessExpression
(
SyntaxKind.SimpleMemberAccessExpression,
MemberAccessExpression
(
SyntaxKind.SimpleMemberAccessExpression, IdentifierName("System"),
IdentifierName("Runtime")
), IdentifierName("InteropServices")
), IdentifierName("Marshal")
), IdentifierName("GetFunctionPointerForDelegate")
), ArgumentList(SingletonSeparatedList(Argument(parameterVariable.Value)))
)
)
);
ctx.SetParameterToVariable(index, id);
}
int resultLocalId = default;
var processReturn = ctx.ReturnLoadType.TypeKind == TypeKind.Delegate;
var oldReturnLoadType = ctx.ReturnLoadType;
if (processReturn)
{
resultLocalId = ctx.DeclareVariable(ctx.ReturnLoadType);
ctx.ReturnLoadType = ctx.Compilation.GetSpecialType(SpecialType.System_IntPtr);
}
next();
if (processReturn)
{
var resultVariable = ctx.ResolveVariable(ctx.ResultVariable.Value);
ctx.SetVariable
(
resultLocalId, ctx => ConditionalExpression
(
BinaryExpression
(
SyntaxKind.EqualsExpression, resultVariable.Value,
MemberAccessExpression
(
SyntaxKind.SimpleMemberAccessExpression, IdentifierName("IntPtr"),
IdentifierName("Zero")
)
), LiteralExpression(SyntaxKind.NullLiteralExpression), InvocationExpression
( // System.Runtime.InteropServices.Marshal.GetDelegateForFunctionPointer<T>(ResultName)
MemberAccessExpression
(
SyntaxKind.SimpleMemberAccessExpression,
MemberAccessExpression
(
SyntaxKind.SimpleMemberAccessExpression,
MemberAccessExpression
(
SyntaxKind.SimpleMemberAccessExpression,
MemberAccessExpression
(
SyntaxKind.SimpleMemberAccessExpression, IdentifierName("System"),
IdentifierName("Runtime")
), IdentifierName("InteropServices")
), IdentifierName("Marshal")
),
GenericName
(
Identifier("GetDelegateForFunctionPointer"),
TypeArgumentList
(
SingletonSeparatedList
(
(TypeSyntax)IdentifierName
(
oldReturnLoadType.ToDisplayString
(SymbolDisplayFormat.FullyQualifiedFormat)
)
)
)
)
),
ArgumentList
(SingletonSeparatedList(Argument(resultVariable.Value)))
)
)
);
ctx.ResultVariable = resultLocalId;
}
}