Implement LOWORD and HIWORD Macros for Extracting Low-Order and High-Order Words from a 32-Bit Value

src/Microsoft.Windows.CsWin32/templates/PInvokeClassMacros.cs

@@ -44,4 +44,18 @@ internal class PInvokeClassMacros
 	/// <param name="h">The high word.</param>
 	/// <returns>The LRESULT value.</returns>
 	internal static global::Windows.Win32.Foundation.LRESULT MAKELRESULT(ushort l, ushort h) => unchecked((global::Windows.Win32.Foundation.LRESULT)(nint)MAKELONG(l, h));
+
+	/// <summary>
+	/// Retrieves the low-order word from the specified 32-bit value.
+	/// </summary>
+	/// <param name="value">The 32-bit value.</param>
+	/// <returns>The low-order word.</returns>
+	internal static ushort LOWORD(uint value) => (ushort)(value & 0xFFFF);
+
+	/// <summary>
+	/// Retrieves the high-order word from the specified 32-bit value.
+	/// </summary>
+	/// <param name="value">The 32-bit value.</param>
+	/// <returns>The high-order word.</returns>
+	internal static ushort HIWORD(uint value) => (ushort)(value >> 16);
 }

test/GenerationSandbox.Tests/MacroTests.cs

@@ -65,4 +65,30 @@ public void MAKELRESULTTest()
             Assert.Equal((LRESULT)(nint)0xFFFFFFFF, MAKELRESULT(0xFFFF, 0xFFFF));
         }
     }
+
+    [Fact]
+    public void LOWORDTest()
+    {
+        Assert.Equal((ushort)0x0000, LOWORD(0x00000000u));
+        Assert.Equal((ushort)0x0001, LOWORD(0x00010001u));
+        Assert.Equal((ushort)0x0000, LOWORD(0xFFFF0000u));
+        Assert.Equal((ushort)0x1234, LOWORD(0x56781234u));
+        Assert.Equal((ushort)0xFFFF, LOWORD(0xFFFFFFFFu));
+        Assert.Equal((ushort)0xABCD, LOWORD(0x1234ABCDu));
+        Assert.Equal((ushort)0x0000, LOWORD(0xFFFF0000u));
+        Assert.Equal((ushort)0x8000, LOWORD(0xFFFF8000u));
+    }
+
+    [Fact]
+    public void HIWORDTest()
+    {
+        Assert.Equal((ushort)0x0000, HIWORD(0x00000000u));
+        Assert.Equal((ushort)0x0001, HIWORD(0x00010001u));
+        Assert.Equal((ushort)0xFFFF, HIWORD(0xFFFF0000u));
+        Assert.Equal((ushort)0x5678, HIWORD(0x56781234u));
+        Assert.Equal((ushort)0xFFFF, HIWORD(0xFFFFFFFFu));
+        Assert.Equal((ushort)0x1234, HIWORD(0x1234ABCDu));
+        Assert.Equal((ushort)0xFFFF, HIWORD(0xFFFF1234u));
+        Assert.Equal((ushort)0x8000, HIWORD(0x80000000u));
+    }
 }

test/GenerationSandbox.Tests/NativeMethods.txt

@@ -15,6 +15,7 @@ GetTickCount
 GetWindowText
 GetWindowTextLength
 HDC_UserSize
+HIWORD
 HRESULT_FROM_WIN32
 IDirectorySearch
 IEnumDebugPropertyInfo
@@ -24,6 +25,7 @@ IShellWindows
 IStream
 KEY_EVENT_RECORD
 LoadLibrary
+LOWORD
 MainAVIHeader
 MAKELPARAM
 MAKELRESULT

test/Microsoft.Windows.CsWin32.Tests/MacrosTests.cs

@@ -15,9 +15,22 @@ public void MacroAPIsGenerateWithAppropriateVisibility(bool publicVisibility)
         Assert.True(this.generator.TryGenerate("MAKELONG", CancellationToken.None));
         this.CollectGeneratedCode(this.generator);
         this.AssertNoDiagnostics();
-        var method = Assert.Single(this.FindGeneratedMethod("MAKELONG"));
+        var makelongMethod = Assert.Single(this.FindGeneratedMethod("MAKELONG"));
+        Assert.True(makelongMethod.Modifiers.Any(publicVisibility ? SyntaxKind.PublicKeyword : SyntaxKind.InternalKeyword));
 
-        Assert.True(method.Modifiers.Any(publicVisibility ? SyntaxKind.PublicKeyword : SyntaxKind.InternalKeyword));
+        this.generator = this.CreateGenerator(DefaultTestGeneratorOptions with { Public = publicVisibility });
+        Assert.True(this.generator.TryGenerate("LOWORD", CancellationToken.None));
+        this.CollectGeneratedCode(this.generator);
+        this.AssertNoDiagnostics();
+        var lowordMethod = Assert.Single(this.FindGeneratedMethod("LOWORD"));
+        Assert.True(lowordMethod.Modifiers.Any(publicVisibility ? SyntaxKind.PublicKeyword : SyntaxKind.InternalKeyword));
+
+        this.generator = this.CreateGenerator(DefaultTestGeneratorOptions with { Public = publicVisibility });
+        Assert.True(this.generator.TryGenerate("HIWORD", CancellationToken.None));
+        this.CollectGeneratedCode(this.generator);
+        this.AssertNoDiagnostics();
+        var hiwordMethod = Assert.Single(this.FindGeneratedMethod("HIWORD"));
+        Assert.True(hiwordMethod.Modifiers.Any(publicVisibility ? SyntaxKind.PublicKeyword : SyntaxKind.InternalKeyword));
     }
 
     [Theory]