Add a "license" property to ndk_headers.

This field points to the license file for the headers being shipped.

Test: make ndk && less $SOONG_OUT/ndk/NOTICE
Bug: None
Change-Id: I386f4e6f6d9776f422ffc09b8dab69e1911b08a4

android/defs.go

@@ -74,6 +74,12 @@ var (
 		},
 		"error")
 
+	Cat = pctx.AndroidStaticRule("Cat",
+		blueprint.RuleParams{
+			Command:     "cat $in > $out",
+			Description: "concatenate licenses $out",
+		})
+
 	// Used only when USE_GOMA=true is set, to restrict non-goma jobs to the local parallelism value
 	localPool = blueprint.NewBuiltinPool("local_pool")
 )

android/module.go

@@ -170,6 +170,7 @@ type HostOrDeviceSupported int
 const (
 	_ HostOrDeviceSupported = iota
 	HostSupported
+	HostSupportedNoCross
 	DeviceSupported
 	HostAndDeviceSupported
 	HostAndDeviceDefault
@@ -326,8 +327,9 @@ func (a *ModuleBase) ArchSpecific() bool {
 func (a *ModuleBase) OsClassSupported() []OsClass {
 	switch a.commonProperties.HostOrDeviceSupported {
 	case HostSupported:
-		// TODO(ccross): explicitly mark host cross support
 		return []OsClass{Host, HostCross}
+	case HostSupportedNoCross:
+		return []OsClass{Host}
 	case DeviceSupported:
 		return []OsClass{Device}
 	case HostAndDeviceSupported:

cc/ndk_headers.go

@@ -46,6 +46,9 @@ type headerProperies struct {
 
 	// List of headers to install. Glob compatible. Common case is "include/**/*.h".
 	Srcs []string
+
+	// Path to the NOTICE file associated with the headers.
+	License string
 }
 
 type headerModule struct {
@@ -54,12 +57,19 @@ type headerModule struct {
 	properties headerProperies
 
 	installPaths []string
+	licensePath  android.ModuleSrcPath
 }
 
 func (m *headerModule) DepsMutator(ctx android.BottomUpMutatorContext) {
 }
 
 func (m *headerModule) GenerateAndroidBuildActions(ctx android.ModuleContext) {
+	if m.properties.License == "" {
+		ctx.PropertyErrorf("license", "field is required")
+	}
+
+	m.licensePath = android.PathForModuleSrc(ctx, m.properties.License)
+
 	srcFiles := ctx.ExpandSources(m.properties.Srcs, nil)
 	for _, header := range srcFiles {
 		// Output path is the sysroot base + "usr/include" + to directory + directory component
@@ -100,6 +110,10 @@ func (m *headerModule) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 
 func ndkHeadersFactory() (blueprint.Module, []interface{}) {
 	module := &headerModule{}
-	return android.InitAndroidArchModule(module, android.HostSupported, android.MultilibFirst,
-		&module.properties)
+	// Host module rather than device module because device module install steps
+	// do not get run when embedded in make. We're not any of the existing
+	// module types that can be exposed via the Android.mk exporter, so just use
+	// a host module.
+	return android.InitAndroidArchModule(module, android.HostSupportedNoCross,
+		android.MultilibFirst, &module.properties)
 }

cc/ndk_sysroot.go

@@ -66,12 +66,12 @@ func init() {
 	pctx.Import("android/soong/common")
 }
 
-func getNdkInstallBase(ctx android.ModuleContext) android.OutputPath {
+func getNdkInstallBase(ctx android.PathContext) android.OutputPath {
 	return android.PathForOutput(ctx, "ndk")
 }
 
 // Returns the main install directory for the NDK sysroot. Usable with --sysroot.
-func getNdkSysrootBase(ctx android.ModuleContext) android.OutputPath {
+func getNdkSysrootBase(ctx android.PathContext) android.OutputPath {
 	return getNdkInstallBase(ctx).Join(ctx, "sysroot")
 }
 
@@ -87,9 +87,11 @@ type ndkSingleton struct{}
 
 func (n *ndkSingleton) GenerateBuildActions(ctx blueprint.SingletonContext) {
 	installPaths := []string{}
+	licensePaths := []string{}
 	ctx.VisitAllModules(func(module blueprint.Module) {
 		if m, ok := module.(*headerModule); ok {
 			installPaths = append(installPaths, m.installPaths...)
+			licensePaths = append(licensePaths, m.licensePath.String())
 		}
 	})
 
@@ -101,12 +103,22 @@ func (n *ndkSingleton) GenerateBuildActions(ctx blueprint.SingletonContext) {
 		}
 	})
 
+	combinedLicense := getNdkInstallBase(ctx).Join(ctx, "NOTICE")
+	ctx.Build(pctx, blueprint.BuildParams{
+		Rule:     android.Cat,
+		Outputs:  []string{combinedLicense.String()},
+		Inputs:   licensePaths,
+		Optional: true,
+	})
+
+	depPaths := append(installPaths, combinedLicense.String())
+
 	// There's a dummy "ndk" rule defined in ndk/Android.mk that depends on
 	// this. `m ndk` will build the sysroots.
 	ctx.Build(pctx, blueprint.BuildParams{
 		Rule:      android.Touch,
 		Outputs:   []string{getNdkSysrootTimestampFile(ctx).String()},
-		Implicits: installPaths,
+		Implicits: depPaths,
 		Optional:  true,
 	})
 }