Adding support for generating unmanaged constants

sources/ClangSharp.PInvokeGenerator/Abstractions/FunctionOrDelegateDesc.cs

@@ -200,18 +200,32 @@ public bool? IsStatic
 
         public bool NeedsReturnFixup
         {
-            get => (Flags & FunctionOrDelegateFlags.NeedsReturnFixup) != 0;
-            set => Flags = value
-                ? Flags | FunctionOrDelegateFlags.NeedsReturnFixup
-                : Flags & ~FunctionOrDelegateFlags.NeedsReturnFixup;
+            get
+            {
+                return (Flags & FunctionOrDelegateFlags.NeedsReturnFixup) != 0;
+            }
+
+            set
+            {
+                Flags = value
+                      ? Flags | FunctionOrDelegateFlags.NeedsReturnFixup
+                      : Flags & ~FunctionOrDelegateFlags.NeedsReturnFixup;
+            }
         }
 
         public bool IsCxxConstructor
         {
-            get => (Flags & FunctionOrDelegateFlags.IsCxxConstructor) != 0;
-            set => Flags = value
-                ? Flags | FunctionOrDelegateFlags.IsCxxConstructor
-                : Flags & ~FunctionOrDelegateFlags.IsCxxConstructor;
+            get
+            {
+                return (Flags & FunctionOrDelegateFlags.IsCxxConstructor) != 0;
+            }
+
+            set
+            {
+                Flags = value
+                      ? Flags | FunctionOrDelegateFlags.IsCxxConstructor
+                      : Flags & ~FunctionOrDelegateFlags.IsCxxConstructor;
+            }
         }
 
         public Action<TCustomAttrGeneratorData> WriteCustomAttrs { get; set; }

sources/ClangSharp.PInvokeGenerator/Abstractions/IOutputBuilder.Visit.cs

@@ -1,5 +1,7 @@
 // Copyright (c) Microsoft and Contributors. All rights reserved. Licensed under the University of Illinois/NCSA Open Source License. See LICENSE.txt in the project root for license information.
 
+using System;
+
 namespace ClangSharp.Abstractions
 {
     internal partial interface IOutputBuilder
@@ -8,7 +10,7 @@ internal partial interface IOutputBuilder
         void SuppressDivider();
 
         void WriteCustomAttribute(string attribute);
-        void WriteIid(string iidName, string iidValue);
+        void WriteIid(string name, Guid value);
         void EmitUsingDirective(string directive);
     }
 }

sources/ClangSharp.PInvokeGenerator/Abstractions/IOutputBuilder.VisitDecl.cs

@@ -4,6 +4,8 @@ namespace ClangSharp.Abstractions
 {
     internal partial interface IOutputBuilder
     {
+        bool IsUncheckedContext { get; }
+
         void BeginInnerValue();
         void EndInnerValue();
 
@@ -14,12 +16,10 @@ internal partial interface IOutputBuilder
         void BeginUnchecked();
         void EndUnchecked();
 
-        void BeginConstant(in ConstantDesc desc);
-        void BeginConstantValue(bool isGetOnlyProperty = false);
+        void BeginValue(in ValueDesc desc);
         void WriteConstantValue(long value);
         void WriteConstantValue(ulong value);
-        void EndConstantValue();
-        void EndConstant(bool isConstant);
+        void EndValue(in ValueDesc desc);
 
         void BeginEnum(in EnumDesc desc);
         void EndEnum();
@@ -29,8 +29,7 @@ internal partial interface IOutputBuilder
         void WriteRegularField(string typeName, string escapedName);
         void EndField(bool isBodyless = true);
 
-        void BeginFunctionOrDelegate<TCustomAttrGeneratorData>(in FunctionOrDelegateDesc<TCustomAttrGeneratorData> info,
-            ref bool isMethodClassUnsafe);
+        void BeginFunctionOrDelegate<TCustomAttrGeneratorData>(in FunctionOrDelegateDesc<TCustomAttrGeneratorData> info, ref bool isMethodClassUnsafe);
         void BeginFunctionInnerPrototype(string escapedName);
         void BeginParameter<TCustomAttrGeneratorData>(in ParameterDesc<TCustomAttrGeneratorData> info);
         void BeginParameterDefault();

sources/ClangSharp.PInvokeGenerator/Abstractions/StructDesc.cs

@@ -46,8 +46,15 @@ public bool HasVtbl
 
         public bool IsUnion
         {
-            get => (Flags & StructFlags.IsUnion) != 0;
-            set => Flags = value ? Flags | StructFlags.IsUnion : Flags & ~StructFlags.IsUnion;
+            get
+            {
+                return (Flags & StructFlags.IsUnion) != 0;
+            }
+
+            set
+            {
+                Flags = value ? Flags | StructFlags.IsUnion : Flags & ~StructFlags.IsUnion;
+            }
         }
 
         public Action<TCustomAttrGeneratorData> WriteCustomAttrs { get; set; }

sources/ClangSharp.PInvokeGenerator/Abstractions/ConstantDesc.cs → sources/ClangSharp.PInvokeGenerator/Abstractions/ValueDesc.cs

@@ -4,13 +4,19 @@
 
 namespace ClangSharp.Abstractions
 {
-    internal struct ConstantDesc
+    internal struct ValueDesc
     {
         public AccessSpecifier AccessSpecifier { get; set; }
         public string TypeName { get; set; }
         public string EscapedName { get; set; }
         public string NativeTypeName { get; set; }
-        public ConstantKind Kind { get; set; }
+        public ValueKind Kind { get; set; }
+        public ValueFlags Flags { get; set; }
         public CXSourceLocation? Location { get; set; }
+
+        public bool HasInitializer => Flags.HasFlag(ValueFlags.Initializer);
+        public bool IsArray => Flags.HasFlag(ValueFlags.Array);
+        public bool IsConstant => Flags.HasFlag(ValueFlags.Constant);
+        public bool IsCopy => Flags.HasFlag(ValueFlags.Copy);
     }
 }

sources/ClangSharp.PInvokeGenerator/Abstractions/ValueKind.cs

@@ -0,0 +1,13 @@
+// Copyright (c) Microsoft and Contributors. All rights reserved. Licensed under the University of Illinois/NCSA Open Source License. See LICENSE.txt in the project root for license information.
+
+namespace ClangSharp.Abstractions
+{
+    internal enum ValueKind
+    {
+        Unknown,
+        Primitive,
+        Enumerator,
+        Unmanaged,
+        String,
+    }
+}

sources/ClangSharp.PInvokeGenerator/Abstractions/ConstantKind.cs → sources/ClangSharp.PInvokeGenerator/Abstractions/ValueModifiers.cs

@@ -5,12 +5,12 @@
 namespace ClangSharp.Abstractions
 {
     [Flags]
-    internal enum ConstantKind
+    internal enum ValueFlags
     {
         None = 0,
-        ReadOnly = 1 << 0,
-        Enumerator = 1 << 1,
-        PrimitiveConstant = 1 << 2,
-        NonPrimitiveConstant = 1 << 3
+        Initializer = 1 << 0,
+        Constant = 1 << 1,
+        Copy = 1 << 2,
+        Array = 1 << 3,
     }
 }

sources/ClangSharp.PInvokeGenerator/CSharp/CSharpOutputBuilder.Visit.cs

@@ -1,5 +1,8 @@
 // Copyright (c) Microsoft and Contributors. All rights reserved. Licensed under the University of Illinois/NCSA Open Source License. See LICENSE.txt in the project root for license information.
 
+using System;
+using System.Runtime.CompilerServices;
+
 namespace ClangSharp.CSharp
 {
     internal partial class CSharpOutputBuilder
@@ -49,13 +52,72 @@ public void WriteDivider(bool force = false)
 
         public void SuppressDivider() => NeedsNewline = false;
 
-        public void WriteIid(string iidName, string iidValue)
+        public void WriteIid(string name, Guid value)
+        {
+            if (_config.GenerateUnmanagedConstants)
+            {
+                AddUsingDirective("System");
+                AddUsingDirective("System.Diagnostics");
+                AddUsingDirective("System.Runtime.CompilerServices");
+                AddUsingDirective("System.Runtime.InteropServices");
+
+                WriteIndented("public static ref readonly Guid ");
+                WriteLine(name);
+                WriteBlockStart();
+
+                WriteIndentedLine("get");
+                WriteBlockStart();
+
+                WriteIndentedLine("ReadOnlySpan<byte> data = new byte[] {");
+                IncreaseIndentation();
+                WriteIndentation();
+
+                WriteValueAsBytes(Unsafe.As<Guid, uint>(ref value), 4);
+
+                WriteLine(',');
+                WriteIndentation();
+
+                WriteValueAsBytes(Unsafe.As<Guid, ushort>(ref Unsafe.AddByteOffset(ref value, (nint)4)), 2);
+
+                WriteLine(',');
+                WriteIndentation();
+
+                WriteValueAsBytes(Unsafe.As<Guid, ushort>(ref Unsafe.AddByteOffset(ref value, (nint)6)), 2);
+
+                for (var i = 8; i < 16; i++)
+                {
+                    WriteLine(',');
+                    WriteIndentation();
+
+                    WriteValueAsBytes(Unsafe.As<Guid, ushort>(ref Unsafe.AddByteOffset(ref value, (nint)i)), 1);
+                }
+
+                WriteNewline();
+                DecreaseIndentation();
+                WriteIndentedLine("};");
+
+                NeedsNewline = true;
+
+                WriteIndentedLine("Debug.Assert(data.Length == Unsafe.SizeOf<Guid>());");
+                WriteIndentedLine("return ref Unsafe.As<byte, Guid>(ref MemoryMarshal.GetReference(data));");
+
+                WriteBlockEnd();
+                WriteBlockEnd();
+            }
+            else
+            {
+                var valueString = value.ToString("X").ToUpperInvariant().Replace("{", "").Replace("}", "").Replace('X', 'x').Replace(",", ", ");
+                WriteIid(name, valueString);
+            }
+        }
+
+        public void WriteIid(string name, string value)
         {
             AddUsingDirective("System");
             WriteIndented("public static readonly Guid ");
-            Write(iidName);
+            Write(name);
             Write(" = new Guid(");
-            Write(iidValue);
+            Write(value);
             Write(")");
             WriteSemicolon();
             WriteNewline();