Add GSI support for android_system_image

GSI's system.img includes system_ext and product artifacts. This patches
android_system_image module so it can include such artifacts when
building GSI.

Bug: 370351758
Test: m android_gsi
Change-Id: Id29678b1101e787e88dbedae38cdbf6d82d1cb95
diff --git a/Android.bp b/Android.bp
index 42b7d83..9763622 100644
--- a/Android.bp
+++ b/Android.bp
@@ -175,6 +175,7 @@
     // Currently, only microdroid, Ravenwood, and cf system image can refer to system-build.prop
     visibility: [
         "//build/make/target/product/generic",
+        "//build/make/target/product/gsi",
         "//packages/modules/Virtualization/build/microdroid",
         "//frameworks/base/ravenwood",
     ],
@@ -186,7 +187,7 @@
     system_ext_specific: true,
     product_config: ":product_config",
     relative_install_path: "etc", // system_ext/etc/build.prop
-    visibility: ["//visibility:private"],
+    visibility: ["//build/make/target/product/gsi"],
 }
 
 build_prop {
@@ -195,7 +196,7 @@
     product_specific: true,
     product_config: ":product_config",
     relative_install_path: "etc", // product/etc/build.prop
-    visibility: ["//visibility:private"],
+    visibility: ["//build/make/target/product/gsi"],
 }
 
 build_prop {
diff --git a/android/packaging.go b/android/packaging.go
index 98c85fa..635922c 100644
--- a/android/packaging.go
+++ b/android/packaging.go
@@ -165,6 +165,10 @@
 	return p.partition
 }
 
+func (p *PackagingSpec) SetPartition(partition string) {
+	p.partition = partition
+}
+
 func (p *PackagingSpec) SkipInstall() bool {
 	return p.skipInstall
 }
@@ -186,6 +190,7 @@
 	// GatherPackagingSpecs gathers PackagingSpecs of transitive dependencies.
 	GatherPackagingSpecs(ctx ModuleContext) map[string]PackagingSpec
 	GatherPackagingSpecsWithFilter(ctx ModuleContext, filter func(PackagingSpec) bool) map[string]PackagingSpec
+	GatherPackagingSpecsWithFilterAndModifier(ctx ModuleContext, filter func(PackagingSpec) bool, modifier func(*PackagingSpec)) map[string]PackagingSpec
 
 	// CopyDepsToZip zips the built artifacts of the dependencies into the given zip file and
 	// returns zip entries in it. This is expected to be called in GenerateAndroidBuildActions,
@@ -444,7 +449,8 @@
 	}
 }
 
-func (p *PackagingBase) GatherPackagingSpecsWithFilter(ctx ModuleContext, filter func(PackagingSpec) bool) map[string]PackagingSpec {
+// See PackageModule.GatherPackagingSpecs
+func (p *PackagingBase) GatherPackagingSpecsWithFilterAndModifier(ctx ModuleContext, filter func(PackagingSpec) bool, modifier func(*PackagingSpec)) map[string]PackagingSpec {
 	// packaging specs gathered from the dep that are not high priorities.
 	var regularPriorities []PackagingSpec
 
@@ -491,6 +497,10 @@
 				}
 			}
 
+			if modifier != nil {
+				modifier(&ps)
+			}
+
 			if _, ok := depTag.(highPriorityDepTag); ok {
 				highPriorities = append(highPriorities, ps)
 			} else {
@@ -552,6 +562,11 @@
 }
 
 // See PackageModule.GatherPackagingSpecs
+func (p *PackagingBase) GatherPackagingSpecsWithFilter(ctx ModuleContext, filter func(PackagingSpec) bool) map[string]PackagingSpec {
+	return p.GatherPackagingSpecsWithFilterAndModifier(ctx, filter, nil)
+}
+
+// See PackageModule.GatherPackagingSpecs
 func (p *PackagingBase) GatherPackagingSpecs(ctx ModuleContext) map[string]PackagingSpec {
 	return p.GatherPackagingSpecsWithFilter(ctx, nil)
 }
diff --git a/compliance/Android.bp b/compliance/Android.bp
index 72c2f27..6662970 100644
--- a/compliance/Android.bp
+++ b/compliance/Android.bp
@@ -35,5 +35,6 @@
     partition_name: "system",
     visibility: [
         "//build/make/target/product/generic",
+        "//build/make/target/product/gsi",
     ],
 }
diff --git a/filesystem/filesystem.go b/filesystem/filesystem.go
index 78e24e2..29e5ec3 100644
--- a/filesystem/filesystem.go
+++ b/filesystem/filesystem.go
@@ -67,6 +67,10 @@
 	BuildLinkerConfigFile(ctx android.ModuleContext, builder *android.RuleBuilder, rebasedDir android.OutputPath)
 	// Function that filters PackagingSpec in PackagingBase.GatherPackagingSpecs()
 	FilterPackagingSpec(spec android.PackagingSpec) bool
+	// Function that modifies PackagingSpec in PackagingBase.GatherPackagingSpecs() to customize.
+	// For example, GSI system.img contains system_ext and product artifacts and their
+	// relPathInPackage need to be rebased to system/system_ext and system/system_product.
+	ModifyPackagingSpec(spec *android.PackagingSpec)
 }
 
 var _ filesystemBuilder = (*filesystem)(nil)
@@ -302,6 +306,10 @@
 	return true
 }
 
+func (f *filesystem) ModifyPackagingSpec(ps *android.PackagingSpec) {
+	// do nothing by default
+}
+
 var pctx = android.NewPackageContext("android/soong/filesystem")
 
 func (f *filesystem) GenerateAndroidBuildActions(ctx android.ModuleContext) {
@@ -792,7 +800,7 @@
 // Note that "apex" module installs its contents to "apex"(fake partition) as well
 // for symbol lookup by imitating "activated" paths.
 func (f *filesystem) gatherFilteredPackagingSpecs(ctx android.ModuleContext) map[string]android.PackagingSpec {
-	specs := f.PackagingBase.GatherPackagingSpecsWithFilter(ctx, f.filesystemBuilder.FilterPackagingSpec)
+	specs := f.PackagingBase.GatherPackagingSpecsWithFilterAndModifier(ctx, f.filesystemBuilder.FilterPackagingSpec, f.filesystemBuilder.ModifyPackagingSpec)
 	return specs
 }
 
@@ -818,13 +826,7 @@
 	android.ModuleBase
 	android.DefaultsModuleBase
 
-	properties filesystemDefaultsProperties
-}
-
-type filesystemDefaultsProperties struct {
-	// Identifies which partition this is for //visibility:any_system_image (and others) visibility
-	// checks, and will be used in the future for API surface checks.
-	Partition_type *string
+	properties FilesystemProperties
 }
 
 // android_filesystem_defaults is a default module for android_filesystem and android_system_image
diff --git a/filesystem/system_image.go b/filesystem/system_image.go
index 672458c..4d176ae 100644
--- a/filesystem/system_image.go
+++ b/filesystem/system_image.go
@@ -18,6 +18,9 @@
 	"android/soong/android"
 	"android/soong/linkerconfig"
 
+	"path/filepath"
+	"strings"
+
 	"github.com/google/blueprint/proptools"
 )
 
@@ -58,5 +61,14 @@
 // for symbol lookup by imitating "activated" paths.
 func (s *systemImage) FilterPackagingSpec(ps android.PackagingSpec) bool {
 	return !ps.SkipInstall() &&
-		(ps.Partition() == "system" || ps.Partition() == "root")
+		(ps.Partition() == "system" || ps.Partition() == "root" ||
+			strings.HasPrefix(ps.Partition(), "system/"))
+}
+
+func (s *systemImage) ModifyPackagingSpec(ps *android.PackagingSpec) {
+	if strings.HasPrefix(ps.Partition(), "system/") {
+		subPartition := strings.TrimPrefix(ps.Partition(), "system/")
+		ps.SetPartition("system")
+		ps.SetRelPathInPackage(filepath.Join(subPartition, ps.RelPathInPackage()))
+	}
 }