Merge pull request #1110 from microsoft/fix968

Emit `DllImportAttribute.EntryPoint` when metadata sets it to a custom value
microsoft · Jan 10, 2024 · e54bb73 · e54bb73
2 parents efd80a7 + 1d5d0ff
commit e54bb73
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Showing 2 changed files with 27 additions and 1 deletion.
diff --git a/src/Microsoft.Windows.CsWin32/Generator.Extern.cs b/src/Microsoft.Windows.CsWin32/Generator.Extern.cs
@@ -190,6 +190,11 @@ private void DeclareExternMethod(MethodDefinitionHandle methodDefinitionHandle)
                 methodName = newName;
             }
 
+            if (!import.Name.IsNil && import.Name != methodDefinition.Name)
+            {
+                entrypoint = this.Reader.GetString(import.Name);
+            }
+
             // If this method releases a handle, recreate the method signature such that we take the struct rather than the SafeHandle as a parameter.
             TypeSyntaxSettings typeSettings = this.MetadataIndex.ReleaseMethods.Contains(entrypoint ?? methodName) ? this.externReleaseSignatureTypeSettings : this.externSignatureTypeSettings;
             MethodSignature<TypeHandleInfo> signature = methodDefinition.DecodeSignature(SignatureHandleProvider.Instance, null);

diff --git a/test/Microsoft.Windows.CsWin32.Tests/ExternMethodTests.cs b/test/Microsoft.Windows.CsWin32.Tests/ExternMethodTests.cs
@@ -52,10 +52,31 @@ public void SetLastError_ByMarshaling(
         AttributeSyntax? attribute = FindDllImportAttribute(originalMethod.AttributeLists) ?? FindDllImportAttribute(originalMethod.Body?.Statements.OfType<LocalFunctionStatementSyntax>().SingleOrDefault()?.AttributeLists ?? default);
         Assert.NotNull(attribute);
         Assert.Equal(expectMarshalingAttribute, attribute.ArgumentList!.Arguments.Any(a => a.NameEquals?.Name.Identifier.ValueText == "SetLastError"));
+    }
+
+    [Fact]
+    public void CustomEntryPointCarriesOver()
+    {
+        this.GenerateApi("FileIconInit");
+        MethodDeclarationSyntax method = Assert.Single(this.FindGeneratedMethod("FileIconInit"));
+        AttributeSyntax? attribute = FindDllImportAttribute(method.AttributeLists);
+        Assert.NotNull(attribute);
+        AttributeArgumentSyntax arg = Assert.Single(attribute.ArgumentList!.Arguments, a => a.NameEquals?.Name.Identifier.ValueText == "EntryPoint");
+        Assert.True(arg.Expression is LiteralExpressionSyntax { RawKind: (int)SyntaxKind.StringLiteralExpression, Token: { Value: "#660" } });
+    }
 
-        static AttributeSyntax? FindDllImportAttribute(SyntaxList<AttributeListSyntax> attributeLists) => attributeLists.SelectMany(al => al.Attributes).FirstOrDefault(a => a.Name.ToString() == "DllImport");
+    [Fact]
+    public void DefaultEntryPointIsNotEmitted()
+    {
+        this.GenerateApi("GetTickCount");
+        MethodDeclarationSyntax method = Assert.Single(this.FindGeneratedMethod("GetTickCount"));
+        AttributeSyntax? attribute = FindDllImportAttribute(method.AttributeLists);
+        Assert.NotNull(attribute);
+        Assert.DoesNotContain(attribute.ArgumentList!.Arguments, a => a.NameEquals?.Name.Identifier.ValueText == "EntryPoint");
     }
 
+    private static AttributeSyntax? FindDllImportAttribute(SyntaxList<AttributeListSyntax> attributeLists) => attributeLists.SelectMany(al => al.Attributes).FirstOrDefault(a => a.Name.ToString() == "DllImport");
+
     private IEnumerable<MethodDeclarationSyntax> GenerateMethod(string methodName)
     {
         this.GenerateApi(methodName);