Add ramdisk image sdk trait to cc_library_headers

Allows an sdk to require that a cc_library_headers module provides a
ramdisk image variant for the prebuilt.

Previously, "ramdisk_available: true" would be set in the generated
prebuilt snapshot for any sdk member that specified
"ramdisk_available: true" in the source module. This change will only
add that setting to the snapshot if the ramdisk image variant trait
was explicitly requested for a member.

Bug: 195754365
Test: m nothing
Change-Id: I21e0dd02d380beabf228a72c463fcc603c77d87f

cc/image_sdk_traits.go

@@ -19,6 +19,7 @@ import "android/soong/android"
 // This file contains support for the image variant sdk traits.
 
 func init() {
+	android.RegisterSdkMemberTrait(ramdiskImageRequiredSdkTrait)
 	android.RegisterSdkMemberTrait(recoveryImageRequiredSdkTrait)
 }
 
@@ -26,6 +27,12 @@ type imageSdkTraitStruct struct {
 	android.SdkMemberTraitBase
 }
 
+var ramdiskImageRequiredSdkTrait android.SdkMemberTrait = &imageSdkTraitStruct{
+	SdkMemberTraitBase: android.SdkMemberTraitBase{
+		PropertyName: "ramdisk_image_required",
+	},
+}
+
 var recoveryImageRequiredSdkTrait android.SdkMemberTrait = &imageSdkTraitStruct{
 	SdkMemberTraitBase: android.SdkMemberTraitBase{
 		PropertyName: "recovery_image_required",

cc/library_headers.go

@@ -35,6 +35,7 @@ var headersLibrarySdkMemberType = &librarySdkMemberType{
 		HostOsDependent: true,
 		Traits: []android.SdkMemberTrait{
 			nativeBridgeSdkTrait,
+			ramdiskImageRequiredSdkTrait,
 			recoveryImageRequiredSdkTrait,
 		},
 	},

cc/library_sdk_member.go

@@ -134,6 +134,16 @@ func (mt *librarySdkMemberType) AddDependencies(ctx android.SdkDependencyContext
 				targets:         targets,
 			})
 
+			// If required add additional dependencies on the image:ramdisk variants.
+			if ctx.RequiresTrait(lib, ramdiskImageRequiredSdkTrait) {
+				memberDependencies = append(memberDependencies, memberDependency{
+					imageVariations: []blueprint.Variation{{Mutator: "image", Variation: android.RamdiskVariation}},
+					// Only add a dependency on the first target as that is the only one which will have an
+					// image:ramdisk variant.
+					targets: targets[:1],
+				})
+			}
+
 			// If required add additional dependencies on the image:recovery variants.
 			if ctx.RequiresTrait(lib, recoveryImageRequiredSdkTrait) {
 				memberDependencies = append(memberDependencies, memberDependency{
@@ -199,6 +209,10 @@ func (mt *librarySdkMemberType) AddPrebuiltModule(ctx android.SdkMemberContext,
 		pbm.AddProperty("native_bridge_supported", true)
 	}
 
+	if ctx.RequiresTrait(ramdiskImageRequiredSdkTrait) {
+		pbm.AddProperty("ramdisk_available", true)
+	}
+
 	if ctx.RequiresTrait(recoveryImageRequiredSdkTrait) {
 		pbm.AddProperty("recovery_available", true)
 	}

sdk/cc_sdk_test.go

@@ -2126,6 +2126,10 @@ myinclude/Test.h -> include/myinclude/Test.h
 		)
 	}
 
+	t.Run("ramdisk", func(t *testing.T) {
+		testImageVariant(t, "ramdisk_available", "ramdisk_image_required")
+	})
+
 	t.Run("recovery", func(t *testing.T) {
 		testImageVariant(t, "recovery_available", "recovery_image_required")
 	})