[APM] Exclude windows only definitions from non windows dlls (#6270)

## Summary of changes
Remove windows only definitions from non windows dlls

## Reason for change
Defs take up space. Removing non needed ones will help keep package size
as low as possible

## Implementation details
Surround windows only defs in #if _WIN32 clauses

## Test coverage

## Other details
<!-- Fixes #{issue} -->

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Author: daniel-romano-DD

tracer/build/_build/CodeGenerators/CallSitesGenerator.cs

@@ -251,6 +251,7 @@ static string GetArgument(Mono.Cecil.CustomAttributeArgument customAttributeArgu
         internal static void GenerateFile(Dictionary<string, AspectClass> aspectClasses, AbsolutePath outputPath)
         {
             var sb = new StringBuilder();
+            bool inWin32Section = false;
             sb.AppendLine("""
                 // <copyright company="Datadog">
                 // Unless explicitly stated otherwise all files in this repository are licensed under the Apache 2 License.
@@ -273,7 +274,25 @@ namespace trace
 
                 foreach (var method in aspectClass.Value.Aspects.OrderBy(static k => k.Key.ToString(), StringComparer.OrdinalIgnoreCase))
                 {
-                    sb.AppendLine(Format("  " + method.Key + method.Value.Subfix()));
+                    bool win32Only = method.Value.Tfms.IsNetFxOnly();
+                    if (win32Only && !inWin32Section)
+                    {
+                        inWin32Section = true;
+                        sb.AppendLine("#if _WIN32");
+                    }
+                    else if (!win32Only && inWin32Section)
+                    {
+                        inWin32Section = false;
+                        sb.AppendLine("#endif");
+                    }
+
+                    sb.AppendLine(Format("  " + method.Key + method.Value.Suffix()));
+                }
+
+                if (inWin32Section)
+                {
+                    inWin32Section = false;
+                    sb.AppendLine("#endif");
                 }
             }
 
@@ -319,7 +338,7 @@ public Aspect() { }
 
             public TargetFrameworks Tfms = TargetFrameworks.None;
 
-            public string Subfix()
+            public string Suffix()
             {
                 return $" {((long)Tfms).ToString()}";
             }

tracer/build/_build/CodeGenerators/CallTargetsGenerator.cs

@@ -546,6 +546,7 @@ namespace trace
 
 
             //Write all CallTargets
+            bool inWin32Section = false;
             sb.AppendLine();
             sb.AppendLine("std::vector<CallTargetDefinition3> g_callTargets=");
             sb.AppendLine("{");
@@ -556,9 +557,27 @@ namespace trace
                                         .ThenBy(static x => x.Key.TargetTypeName)
                                         .ThenBy(static x => x.Key.TargetMethodName))
             {
+                bool win32Only = definition.Value.IsNetFxOnly();
+                if (win32Only && !inWin32Section)
+                {
+                    inWin32Section = true;
+                    sb.AppendLine("#if _WIN32");
+                }
+                else if (!win32Only && inWin32Section)
+                {
+                    inWin32Section = false;
+                    sb.AppendLine("#endif");
+                }
+
                 sb.AppendLine(GetCallTarget(definition.Key, signatures[GetSignature(definition.Key)], definition.Value, x++));
             }
 
+            if (inWin32Section)
+            {
+                inWin32Section = false;
+                sb.AppendLine("#endif");
+            }
+
             sb.AppendLine("""
                 };
                 }
@@ -639,7 +658,6 @@ internal static void GenerateJsonFile(Dictionary<CallTargetDefinitionSource, Tar
             Logger.Information("CallTarget definitions File saved: {File}", fileName);
         }
 
-
         internal static TargetFrameworks GetCategory(TargetFramework tfm)
         {
             return (TargetFrameworks)Enum.Parse<TargetFrameworks>(tfm.ToString().ToUpper().Replace('.', '_'));

tracer/build/_build/CodeGenerators/TargetFrameworks.cs

@@ -16,14 +16,16 @@ internal enum TargetFrameworks : uint
     // NOTE : When modifying this file make sure to update the TargetFrameworks enum in the ClrProfiler folder inside the Datadog.Trace project
 
     NET461 = 1,
-    NET462 = 2,
-    NETSTANDARD2_0 = 4,
-    NETCOREAPP2_1 = 8,
-    NETCOREAPP3_0 = 16,
-    NETCOREAPP3_1 = 32,
-    NET5_0 = 64,
-    NET6_0 = 128,
-    NET7_0 = 256,
-    NET8_0 = 512,
-    NET0_0 = 1024,
+    NETSTANDARD2_0 = 2,
+    NETCOREAPP3_1 = 4,
+    NET6_0 = 8,
+}
+
+
+internal static class TargetFrameworksExtensions
+{ 
+    public static bool IsNetFxOnly(this TargetFrameworks tfm)
+    {
+        return tfm == TargetFrameworks.NET461;
+    }
 }

tracer/src/Datadog.Trace/ClrProfiler/TargetFrameworks.cs

@@ -14,14 +14,7 @@ internal enum TargetFrameworks : uint
     // NOTE : When modifying this file make sure to update the TargetFrameworks enum in the CodeGenerator folder inside the _build project
 
     NET461 = 1,
-    NET462 = 2,
-    NETSTANDARD2_0 = 4,
-    NETCOREAPP2_1 = 8,
-    NETCOREAPP3_0 = 16,
-    NETCOREAPP3_1 = 32,
-    NET5_0 = 64,
-    NET6_0 = 128,
-    NET7_0 = 256,
-    NET8_0 = 512,
-    NET9_0 = 1024,
+    NETSTANDARD2_0 = 2,
+    NETCOREAPP3_1 = 4,
+    NET6_0 = 8,
 }