Add conditions_default for soong config variables.
Each variable can specify a conditions_default for properties to be used
when the variable is not set, not set to a true value (for bools), or is
set to a value that is not present in the module (for strings).
Test: m nothing
Test: go test soong tests
Change-Id: I76ec026da2369b407f0f530f77760f530e7958fc
diff --git a/android/soongconfig/modules.go b/android/soongconfig/modules.go
index 9f3f804..c62e76d 100644
--- a/android/soongconfig/modules.go
+++ b/android/soongconfig/modules.go
@@ -26,6 +26,8 @@
"github.com/google/blueprint/proptools"
)
+const conditionsDefault = "conditions_default"
+
var soongConfigProperty = proptools.FieldNameForProperty("soong_config_variables")
// loadSoongConfigModuleTypeDefinition loads module types from an Android.bp file. It caches the
@@ -145,32 +147,10 @@
return errs
}
- mt := &ModuleType{
- affectableProperties: props.Properties,
- ConfigNamespace: props.Config_namespace,
- BaseModuleType: props.Module_type,
- variableNames: props.Variables,
- }
- v.ModuleTypes[props.Name] = mt
-
- for _, name := range props.Bool_variables {
- if name == "" {
- return []error{fmt.Errorf("bool_variable name must not be blank")}
- }
-
- mt.Variables = append(mt.Variables, newBoolVariable(name))
- }
-
- for _, name := range props.Value_variables {
- if name == "" {
- return []error{fmt.Errorf("value_variables entry must not be blank")}
- }
-
- mt.Variables = append(mt.Variables, &valueVariable{
- baseVariable: baseVariable{
- variable: name,
- },
- })
+ if mt, errs := newModuleType(props); len(errs) > 0 {
+ return errs
+ } else {
+ v.ModuleTypes[props.Name] = mt
}
return nil
@@ -196,6 +176,12 @@
return []error{fmt.Errorf("values property must be set")}
}
+ for _, name := range stringProps.Values {
+ if err := checkVariableName(name); err != nil {
+ return []error{fmt.Errorf("soong_config_string_variable: values property error %s", err)}
+ }
+ }
+
v.variables[base.variable] = &stringVariable{
baseVariable: base,
values: CanonicalizeToProperties(stringProps.Values),
@@ -417,8 +403,7 @@
// PropertiesToApply returns the applicable properties from a ModuleType that should be applied
// based on SoongConfig values.
// Expects that props contains a struct field with name soong_config_variables. The fields within
-// soong_config_variables are expected to be in the same order as moduleType.Variables. In general,
-// props should be generated via CreateProperties.
+// soong_config_variables are expected to be in the same order as moduleType.Variables.
func PropertiesToApply(moduleType *ModuleType, props reflect.Value, config SoongConfig) ([]interface{}, error) {
var ret []interface{}
props = props.Elem().FieldByName(soongConfigProperty)
@@ -441,6 +426,46 @@
variableNames []string
}
+func newModuleType(props *ModuleTypeProperties) (*ModuleType, []error) {
+ mt := &ModuleType{
+ affectableProperties: props.Properties,
+ ConfigNamespace: props.Config_namespace,
+ BaseModuleType: props.Module_type,
+ variableNames: props.Variables,
+ }
+
+ for _, name := range props.Bool_variables {
+ if err := checkVariableName(name); err != nil {
+ return nil, []error{fmt.Errorf("bool_variables %s", err)}
+ }
+
+ mt.Variables = append(mt.Variables, newBoolVariable(name))
+ }
+
+ for _, name := range props.Value_variables {
+ if err := checkVariableName(name); err != nil {
+ return nil, []error{fmt.Errorf("value_variables %s", err)}
+ }
+
+ mt.Variables = append(mt.Variables, &valueVariable{
+ baseVariable: baseVariable{
+ variable: name,
+ },
+ })
+ }
+
+ return mt, nil
+}
+
+func checkVariableName(name string) error {
+ if name == "" {
+ return fmt.Errorf("name must not be blank")
+ } else if name == conditionsDefault {
+ return fmt.Errorf("%q is reserved", conditionsDefault)
+ }
+ return nil
+}
+
type soongConfigVariable interface {
// variableProperty returns the name of the variable.
variableProperty() string
@@ -474,7 +499,10 @@
func (s *stringVariable) variableValuesType() reflect.Type {
var fields []reflect.StructField
- for _, v := range s.values {
+ var values []string
+ values = append(values, s.values...)
+ values = append(values, conditionsDefault)
+ for _, v := range values {
fields = append(fields, reflect.StructField{
Name: proptools.FieldNameForProperty(v),
Type: emptyInterfaceType,
@@ -484,26 +512,36 @@
return reflect.StructOf(fields)
}
+// initializeProperties initializes properties to zero value of typ for supported values and a final
+// conditions default field.
func (s *stringVariable) initializeProperties(v reflect.Value, typ reflect.Type) {
for i := range s.values {
v.Field(i).Set(reflect.Zero(typ))
}
+ v.Field(len(s.values)).Set(reflect.Zero(typ)) // conditions default is the final value
}
+// Extracts an interface from values containing the properties to apply based on config.
+// If config does not match a value with a non-nil property set, the default value will be returned.
func (s *stringVariable) PropertiesToApply(config SoongConfig, values reflect.Value) (interface{}, error) {
for j, v := range s.values {
- if config.String(s.variable) == v {
- return values.Field(j).Interface(), nil
+ f := values.Field(j)
+ if config.String(s.variable) == v && !f.Elem().IsNil() {
+ return f.Interface(), nil
}
}
-
- return nil, nil
+ // if we have reached this point, we have checked all valid values of string and either:
+ // * the value was not set
+ // * the value was set but that value was not specified in the Android.bp file
+ return values.Field(len(s.values)).Interface(), nil
}
+// Struct to allow conditions set based on a boolean variable
type boolVariable struct {
baseVariable
}
+// newBoolVariable constructs a boolVariable with the given name
func newBoolVariable(name string) *boolVariable {
return &boolVariable{
baseVariable{
@@ -516,18 +554,82 @@
return emptyInterfaceType
}
+// initializeProperties initializes a property to zero value of typ with an additional conditions
+// default field.
func (b boolVariable) initializeProperties(v reflect.Value, typ reflect.Type) {
- v.Set(reflect.Zero(typ))
+ initializePropertiesWithDefault(v, typ)
}
-func (b boolVariable) PropertiesToApply(config SoongConfig, values reflect.Value) (interface{}, error) {
- if config.Bool(b.variable) {
- return values.Interface(), nil
+// initializePropertiesWithDefault, initialize with zero value, v to contain a field for each field
+// in typ, with an additional field for defaults of type typ. This should be used to initialize
+// boolVariable, valueVariable, or any future implementations of soongConfigVariable which support
+// one variable and a default.
+func initializePropertiesWithDefault(v reflect.Value, typ reflect.Type) {
+ sTyp := typ.Elem()
+ var fields []reflect.StructField
+ for i := 0; i < sTyp.NumField(); i++ {
+ fields = append(fields, sTyp.Field(i))
}
+ // create conditions_default field
+ nestedFieldName := proptools.FieldNameForProperty(conditionsDefault)
+ fields = append(fields, reflect.StructField{
+ Name: nestedFieldName,
+ Type: typ,
+ })
+
+ newTyp := reflect.PtrTo(reflect.StructOf(fields))
+ v.Set(reflect.Zero(newTyp))
+}
+
+// conditionsDefaultField extracts the conditions_default field from v. This is always the final
+// field if initialized with initializePropertiesWithDefault.
+func conditionsDefaultField(v reflect.Value) reflect.Value {
+ return v.Field(v.NumField() - 1)
+}
+
+// removeDefault removes the conditions_default field from values while retaining values from all
+// other fields. This allows
+func removeDefault(values reflect.Value) reflect.Value {
+ v := values.Elem().Elem()
+ s := conditionsDefaultField(v)
+ // if conditions_default field was not set, there will be no issues extending properties.
+ if !s.IsValid() {
+ return v
+ }
+
+ // If conditions_default field was set, it has the correct type for our property. Create a new
+ // reflect.Value of the conditions_default type and copy all fields (except for
+ // conditions_default) based on values to the result.
+ res := reflect.New(s.Type().Elem())
+ for i := 0; i < res.Type().Elem().NumField(); i++ {
+ val := v.Field(i)
+ res.Elem().Field(i).Set(val)
+ }
+
+ return res
+}
+
+// PropertiesToApply returns an interface{} value based on initializeProperties to be applied to
+// the module. If the value was not set, conditions_default interface will be returned; otherwise,
+// the interface in values, without conditions_default will be returned.
+func (b boolVariable) PropertiesToApply(config SoongConfig, values reflect.Value) (interface{}, error) {
+ // If this variable was not referenced in the module, there are no properties to apply.
+ if values.Elem().IsZero() {
+ return nil, nil
+ }
+ if config.Bool(b.variable) {
+ values = removeDefault(values)
+ return values.Interface(), nil
+ }
+ v := values.Elem().Elem()
+ if f := conditionsDefaultField(v); f.IsValid() {
+ return f.Interface(), nil
+ }
return nil, nil
}
+// Struct to allow conditions set based on a value variable, supporting string substitution.
type valueVariable struct {
baseVariable
}
@@ -536,17 +638,28 @@
return emptyInterfaceType
}
+// initializeProperties initializes a property to zero value of typ with an additional conditions
+// default field.
func (s *valueVariable) initializeProperties(v reflect.Value, typ reflect.Type) {
- v.Set(reflect.Zero(typ))
+ initializePropertiesWithDefault(v, typ)
}
+// PropertiesToApply returns an interface{} value based on initializeProperties to be applied to
+// the module. If the variable was not set, conditions_default interface will be returned;
+// otherwise, the interface in values, without conditions_default will be returned with all
+// appropriate string substitutions based on variable being set.
func (s *valueVariable) PropertiesToApply(config SoongConfig, values reflect.Value) (interface{}, error) {
- if !config.IsSet(s.variable) || !values.IsValid() {
+ // If this variable was not referenced in the module, there are no properties to apply.
+ if !values.IsValid() || values.Elem().IsZero() {
return nil, nil
}
+ if !config.IsSet(s.variable) {
+ return conditionsDefaultField(values.Elem().Elem()).Interface(), nil
+ }
configValue := config.String(s.variable)
- propStruct := values.Elem().Elem()
+ values = removeDefault(values)
+ propStruct := values.Elem()
if !propStruct.IsValid() {
return nil, nil
}