fs: Add raw_binary rule

Raw binaries are used in bare-metal environments such as early boot of
pVMs (protected virtual machines). Add a new target rule called
'raw_binary' which converts an executable to the raw binary format.

Test: m pvmfw
Change-Id: I701b703a0f12df891b714fe29e320914f167cd04

filesystem/Android.bp

@@ -15,6 +15,7 @@ bootstrap_go_package {
         "bootimg.go",
         "filesystem.go",
         "logical_partition.go",
+        "raw_binary.go",
         "system_image.go",
         "vbmeta.go",
         "testing.go",

filesystem/raw_binary.go

@@ -0,0 +1,120 @@
+// Copyright (C) 2022 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package filesystem
+
+import (
+	"fmt"
+
+	"github.com/google/blueprint"
+	"github.com/google/blueprint/proptools"
+
+	"android/soong/android"
+)
+
+var (
+	toRawBinary = pctx.AndroidStaticRule("toRawBinary",
+		blueprint.RuleParams{
+			Command:     "${objcopy} --output-target=binary ${in} ${out}",
+			CommandDeps: []string{"$objcopy"},
+		},
+		"objcopy")
+)
+
+func init() {
+	pctx.Import("android/soong/cc/config")
+
+	android.RegisterModuleType("raw_binary", rawBinaryFactory)
+}
+
+type rawBinary struct {
+	android.ModuleBase
+
+	properties rawBinaryProperties
+
+	output     android.OutputPath
+	installDir android.InstallPath
+}
+
+type rawBinaryProperties struct {
+	// Set the name of the output. Defaults to <module_name>.bin.
+	Stem *string
+
+	// Name of input executable. Can be a name of a target.
+	Src *string `android:"path,arch_variant"`
+}
+
+func rawBinaryFactory() android.Module {
+	module := &rawBinary{}
+	module.AddProperties(&module.properties)
+	android.InitAndroidArchModule(module, android.DeviceSupported, android.MultilibFirst)
+	return module
+}
+
+func (r *rawBinary) DepsMutator(ctx android.BottomUpMutatorContext) {
+	// do nothing
+}
+
+func (r *rawBinary) installFileName() string {
+	return proptools.StringDefault(r.properties.Stem, r.BaseModuleName()+".bin")
+}
+
+func (r *rawBinary) GenerateAndroidBuildActions(ctx android.ModuleContext) {
+	inputFile := android.PathForModuleSrc(ctx, proptools.String(r.properties.Src))
+	outputFile := android.PathForModuleOut(ctx, r.installFileName()).OutputPath
+
+	ctx.Build(pctx, android.BuildParams{
+		Rule:        toRawBinary,
+		Description: "prefix symbols " + outputFile.Base(),
+		Output:      outputFile,
+		Input:       inputFile,
+		Args: map[string]string{
+			"objcopy": "${config.ClangBin}/llvm-objcopy",
+		},
+	})
+
+	r.output = outputFile
+	r.installDir = android.PathForModuleInstall(ctx, "etc")
+	ctx.InstallFile(r.installDir, r.installFileName(), r.output)
+}
+
+var _ android.AndroidMkEntriesProvider = (*rawBinary)(nil)
+
+// Implements android.AndroidMkEntriesProvider
+func (r *rawBinary) AndroidMkEntries() []android.AndroidMkEntries {
+	return []android.AndroidMkEntries{android.AndroidMkEntries{
+		Class:      "ETC",
+		OutputFile: android.OptionalPathForPath(r.output),
+	}}
+}
+
+var _ Filesystem = (*rawBinary)(nil)
+
+func (r *rawBinary) OutputPath() android.Path {
+	return r.output
+}
+
+func (r *rawBinary) SignedOutputPath() android.Path {
+	return nil
+}
+
+var _ android.OutputFileProducer = (*rawBinary)(nil)
+
+// Implements android.OutputFileProducer
+func (r *rawBinary) OutputFiles(tag string) (android.Paths, error) {
+	if tag == "" {
+		return []android.Path{r.output}, nil
+	}
+	return nil, fmt.Errorf("unsupported module reference tag %q", tag)
+}