android/makevars.go

// Copyright 2016 Google Inc. All rights reserved.
//
// 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 android

import (
	"bytes"
	"fmt"
	"path/filepath"
	"runtime"
	"sort"
	"strings"

	"github.com/google/blueprint"
	"github.com/google/blueprint/pathtools"
	"github.com/google/blueprint/proptools"
)

func init() {
	RegisterMakeVarsProvider(pctx, androidMakeVarsProvider)
}

func androidMakeVarsProvider(ctx MakeVarsContext) {
	ctx.Strict("MIN_SUPPORTED_SDK_VERSION", ctx.Config().MinSupportedSdkVersion().String())
}

// /////////////////////////////////////////////////////////////////////////////

// BaseMakeVarsContext contains the common functions for other packages to use
// to declare make variables
type BaseMakeVarsContext interface {
	Config() Config
	DeviceConfig() DeviceConfig
	AddNinjaFileDeps(deps ...string)

	Failed() bool

	// These are equivalent to Strict and Check, but do not attempt to
	// evaluate the values before writing them to the Makefile. They can
	// be used when all ninja variables have already been evaluated through
	// Eval().
	StrictRaw(name, value string)
	CheckRaw(name, value string)

	// GlobWithDeps returns a list of files that match the specified pattern but do not match any
	// of the patterns in excludes.  It also adds efficient dependencies to rerun the primary
	// builder whenever a file matching the pattern as added or removed, without rerunning if a
	// file that does not match the pattern is added to a searched directory.
	GlobWithDeps(pattern string, excludes []string) ([]string, error)

	// Phony creates a phony rule in Make, which will allow additional DistForGoal
	// dependencies to be added to it.  Phony can be called on the same name multiple
	// times to add additional dependencies.
	Phony(names string, deps ...Path)

	// DistForGoal creates a rule to copy one or more Paths to the artifacts
	// directory on the build server when the specified goal is built.
	DistForGoal(goal string, paths ...Path)

	// DistForGoalWithFilename creates a rule to copy a Path to the artifacts
	// directory on the build server with the given filename when the specified
	// goal is built.
	DistForGoalWithFilename(goal string, path Path, filename string)

	// DistForGoals creates a rule to copy one or more Paths to the artifacts
	// directory on the build server when any of the specified goals are built.
	DistForGoals(goals []string, paths ...Path)

	// DistForGoalsWithFilename creates a rule to copy a Path to the artifacts
	// directory on the build server with the given filename when any of the
	// specified goals are built.
	DistForGoalsWithFilename(goals []string, path Path, filename string)
}

// MakeVarsContext contains the set of functions available for MakeVarsProvider
// and SingletonMakeVarsProvider implementations.
type MakeVarsContext interface {
	BaseMakeVarsContext

	ModuleName(module blueprint.Module) string
	ModuleDir(module blueprint.Module) string
	ModuleSubDir(module blueprint.Module) string
	ModuleType(module blueprint.Module) string
	ModuleProvider(module blueprint.Module, key blueprint.AnyProviderKey) any
	moduleProvider(module blueprint.Module, key blueprint.AnyProviderKey) (any, bool)
	BlueprintFile(module blueprint.Module) string

	ModuleErrorf(module blueprint.Module, format string, args ...interface{})
	Errorf(format string, args ...interface{})

	VisitAllModules(visit func(Module))
	VisitAllModulesIf(pred func(Module) bool, visit func(Module))

	// Verify the make variable matches the Soong version, fail the build
	// if it does not. If the make variable is empty, just set it.
	Strict(name, ninjaStr string)
	// Check to see if the make variable matches the Soong version, warn if
	// it does not. If the make variable is empty, just set it.
	Check(name, ninjaStr string)

	// These are equivalent to the above, but sort the make and soong
	// variables before comparing them. They also show the unique entries
	// in each list when displaying the difference, instead of the entire
	// string.
	StrictSorted(name, ninjaStr string)
	CheckSorted(name, ninjaStr string)

	// Evaluates a ninja string and returns the result. Used if more
	// complicated modification needs to happen before giving it to Make.
	Eval(ninjaStr string) (string, error)
}

// MakeVarsModuleContext contains the set of functions available for modules
// implementing the ModuleMakeVarsProvider interface.
type MakeVarsModuleContext interface {
	BaseMakeVarsContext
}

var _ PathContext = MakeVarsContext(nil)

type MakeVarsProvider func(ctx MakeVarsContext)

func RegisterMakeVarsProvider(pctx PackageContext, provider MakeVarsProvider) {
	makeVarsInitProviders = append(makeVarsInitProviders, makeVarsProvider{pctx, provider})
}

// SingletonMakeVarsProvider is a Singleton with an extra method to provide extra values to be exported to Make.
type SingletonMakeVarsProvider interface {
	// MakeVars uses a MakeVarsContext to provide extra values to be exported to Make.
	MakeVars(ctx MakeVarsContext)
}

var singletonMakeVarsProvidersKey = NewOnceKey("singletonMakeVarsProvidersKey")

func getSingletonMakevarsProviders(config Config) *[]makeVarsProvider {
	return config.Once(singletonMakeVarsProvidersKey, func() interface{} {
		return &[]makeVarsProvider{}
	}).(*[]makeVarsProvider)
}

// registerSingletonMakeVarsProvider adds a singleton that implements SingletonMakeVarsProvider to
// the list of MakeVarsProviders to run.
func registerSingletonMakeVarsProvider(config Config, singleton SingletonMakeVarsProvider) {
	// Singletons are registered on the Context and may be different between different Contexts,
	// for example when running multiple tests.  Store the SingletonMakeVarsProviders in the
	// Config so they are attached to the Context.
	singletonMakeVarsProviders := getSingletonMakevarsProviders(config)

	*singletonMakeVarsProviders = append(*singletonMakeVarsProviders,
		makeVarsProvider{pctx, singletonMakeVarsProviderAdapter(singleton)})
}

// singletonMakeVarsProviderAdapter converts a SingletonMakeVarsProvider to a MakeVarsProvider.
func singletonMakeVarsProviderAdapter(singleton SingletonMakeVarsProvider) MakeVarsProvider {
	return func(ctx MakeVarsContext) { singleton.MakeVars(ctx) }
}

// ModuleMakeVarsProvider is a Module with an extra method to provide extra values to be exported to Make.
type ModuleMakeVarsProvider interface {
	Module

	// MakeVars uses a MakeVarsModuleContext to provide extra values to be exported to Make.
	MakeVars(ctx MakeVarsModuleContext)
}

// /////////////////////////////////////////////////////////////////////////////

func makeVarsSingletonFunc() Singleton {
	return &makeVarsSingleton{}
}

type makeVarsSingleton struct {
	varsForTesting     []makeVarsVariable
	installsForTesting []byte
}

type makeVarsProvider struct {
	pctx PackageContext
	call MakeVarsProvider
}

// Collection of makevars providers that are registered in init() methods.
var makeVarsInitProviders []makeVarsProvider

type makeVarsContext struct {
	SingletonContext
	config  Config
	pctx    PackageContext
	vars    []makeVarsVariable
	phonies []phony
	dists   []dist
}

var _ MakeVarsContext = &makeVarsContext{}

type makeVarsVariable struct {
	name   string
	value  string
	sort   bool
	strict bool
}

type phony struct {
	name string
	deps []string
}

type dist struct {
	goals []string
	paths []string
}

func (s *makeVarsSingleton) GenerateBuildActions(ctx SingletonContext) {
	if !ctx.Config().KatiEnabled() {
		return
	}

	outFile := absolutePath(PathForOutput(ctx,
		"make_vars"+proptools.String(ctx.Config().productVariables.Make_suffix)+".mk").String())

	lateOutFile := absolutePath(PathForOutput(ctx,
		"late"+proptools.String(ctx.Config().productVariables.Make_suffix)+".mk").String())

	installsFile := absolutePath(PathForOutput(ctx,
		"installs"+proptools.String(ctx.Config().productVariables.Make_suffix)+".mk").String())

	if ctx.Failed() {
		return
	}

	var vars []makeVarsVariable
	var dists []dist
	var phonies []phony
	var katiInstalls []katiInstall
	var katiSymlinks []katiInstall

	providers := append([]makeVarsProvider(nil), makeVarsInitProviders...)
	providers = append(providers, *getSingletonMakevarsProviders(ctx.Config())...)

	for _, provider := range providers {
		mctx := &makeVarsContext{
			SingletonContext: ctx,
			pctx:             provider.pctx,
		}

		provider.call(mctx)

		vars = append(vars, mctx.vars...)
		phonies = append(phonies, mctx.phonies...)
		dists = append(dists, mctx.dists...)
	}

	ctx.VisitAllModules(func(m Module) {
		if provider, ok := m.(ModuleMakeVarsProvider); ok && m.Enabled() {
			mctx := &makeVarsContext{
				SingletonContext: ctx,
			}

			provider.MakeVars(mctx)

			vars = append(vars, mctx.vars...)
			phonies = append(phonies, mctx.phonies...)
			dists = append(dists, mctx.dists...)
		}

		if m.ExportedToMake() {
			katiInstalls = append(katiInstalls, m.base().katiInstalls...)
			katiSymlinks = append(katiSymlinks, m.base().katiSymlinks...)
		}
	})

	if ctx.Failed() {
		return
	}

	sort.Slice(vars, func(i, j int) bool {
		return vars[i].name < vars[j].name
	})
	sort.Slice(phonies, func(i, j int) bool {
		return phonies[i].name < phonies[j].name
	})
	lessArr := func(a, b []string) bool {
		if len(a) == len(b) {
			for i := range a {
				if a[i] < b[i] {
					return true
				}
			}
			return false
		}
		return len(a) < len(b)
	}
	sort.Slice(dists, func(i, j int) bool {
		return lessArr(dists[i].goals, dists[j].goals) || lessArr(dists[i].paths, dists[j].paths)
	})

	outBytes := s.writeVars(vars)

	if err := pathtools.WriteFileIfChanged(outFile, outBytes, 0666); err != nil {
		ctx.Errorf(err.Error())
	}

	lateOutBytes := s.writeLate(phonies, dists)

	if err := pathtools.WriteFileIfChanged(lateOutFile, lateOutBytes, 0666); err != nil {
		ctx.Errorf(err.Error())
	}

	installsBytes := s.writeInstalls(katiInstalls, katiSymlinks)
	if err := pathtools.WriteFileIfChanged(installsFile, installsBytes, 0666); err != nil {
		ctx.Errorf(err.Error())
	}

	// Only save state for tests when testing.
	if ctx.Config().RunningInsideUnitTest() {
		s.varsForTesting = vars
		s.installsForTesting = installsBytes
	}
}

func (s *makeVarsSingleton) writeVars(vars []makeVarsVariable) []byte {
	buf := &bytes.Buffer{}

	fmt.Fprint(buf, `# Autogenerated file

# Compares SOONG_$(1) against $(1), and warns if they are not equal.
#
# If the original variable is empty, then just set it to the SOONG_ version.
#
# $(1): Name of the variable to check
# $(2): If not-empty, sort the values before comparing
# $(3): Extra snippet to run if it does not match
define soong-compare-var
ifneq ($$($(1)),)
  my_val_make := $$(strip $(if $(2),$$(sort $$($(1))),$$($(1))))
  my_val_soong := $(if $(2),$$(sort $$(SOONG_$(1))),$$(SOONG_$(1)))
  ifneq ($$(my_val_make),$$(my_val_soong))
    $$(warning $(1) does not match between Make and Soong:)
    $(if $(2),$$(warning Make  adds: $$(filter-out $$(my_val_soong),$$(my_val_make))),$$(warning Make : $$(my_val_make)))
    $(if $(2),$$(warning Soong adds: $$(filter-out $$(my_val_make),$$(my_val_soong))),$$(warning Soong: $$(my_val_soong)))
    $(3)
  endif
  my_val_make :=
  my_val_soong :=
else
  $(1) := $$(SOONG_$(1))
endif
.KATI_READONLY := $(1) SOONG_$(1)
endef

my_check_failed := false

`)

	// Write all the strict checks out first so that if one of them errors,
	// we get all of the strict errors printed, but not the non-strict
	// warnings.
	for _, v := range vars {
		if !v.strict {
			continue
		}

		sort := ""
		if v.sort {
			sort = "true"
		}

		fmt.Fprintf(buf, "SOONG_%s := %s\n", v.name, v.value)
		fmt.Fprintf(buf, "$(eval $(call soong-compare-var,%s,%s,my_check_failed := true))\n\n", v.name, sort)
	}

	fmt.Fprint(buf, `
ifneq ($(my_check_failed),false)
  $(error Soong variable check failed)
endif
my_check_failed :=


`)

	for _, v := range vars {
		if v.strict {
			continue
		}

		sort := ""
		if v.sort {
			sort = "true"
		}

		fmt.Fprintf(buf, "SOONG_%s := %s\n", v.name, v.value)
		fmt.Fprintf(buf, "$(eval $(call soong-compare-var,%s,%s))\n\n", v.name, sort)
	}

	fmt.Fprintln(buf, "\nsoong-compare-var :=")

	fmt.Fprintln(buf)

	return buf.Bytes()
}

func (s *makeVarsSingleton) writeLate(phonies []phony, dists []dist) []byte {
	buf := &bytes.Buffer{}

	fmt.Fprint(buf, `# Autogenerated file

# Values written by Soong read after parsing all Android.mk files.


`)

	for _, phony := range phonies {
		fmt.Fprintf(buf, ".PHONY: %s\n", phony.name)
		fmt.Fprintf(buf, "%s: %s\n", phony.name, strings.Join(phony.deps, "\\\n  "))
	}

	fmt.Fprintln(buf)

	for _, dist := range dists {
		fmt.Fprintf(buf, ".PHONY: %s\n", strings.Join(dist.goals, " "))
		fmt.Fprintf(buf, "$(call dist-for-goals,%s,%s)\n",
			strings.Join(dist.goals, " "), strings.Join(dist.paths, " "))
	}

	return buf.Bytes()
}

// writeInstalls writes the list of install rules generated by Soong to a makefile.  The rules
// are exported to Make instead of written directly to the ninja file so that main.mk can add
// the dependencies from the `required` property that are hard to resolve in Soong.
func (s *makeVarsSingleton) writeInstalls(installs, symlinks []katiInstall) []byte {
	buf := &bytes.Buffer{}

	fmt.Fprint(buf, `# Autogenerated file

# Values written by Soong to generate install rules that can be amended by Kati.


`)

	preserveSymlinksFlag := "-d"
	if runtime.GOOS == "darwin" {
		preserveSymlinksFlag = "-R"
	}

	for _, install := range installs {
		// Write a rule for each install request in the form:
		//  to: from [ deps ] [ | order only deps ]
		//       cp -f -d $< $@ [ && chmod +x $@ ]
		fmt.Fprintf(buf, "%s: %s", install.to.String(), install.from.String())
		for _, dep := range install.implicitDeps {
			fmt.Fprintf(buf, " %s", dep.String())
		}
		if extraFiles := install.extraFiles; extraFiles != nil {
			fmt.Fprintf(buf, " %s", extraFiles.zip.String())
		}
		if len(install.orderOnlyDeps) > 0 {
			fmt.Fprintf(buf, " |")
		}
		for _, dep := range install.orderOnlyDeps {
			fmt.Fprintf(buf, " %s", dep.String())
		}
		fmt.Fprintln(buf)
		fmt.Fprintln(buf, "\t@echo \"Install: $@\"")
		fmt.Fprintf(buf, "\trm -f $@ && cp -f %s $< $@\n", preserveSymlinksFlag)
		if install.executable {
			fmt.Fprintf(buf, "\tchmod +x $@\n")
		}
		if extraFiles := install.extraFiles; extraFiles != nil {
			fmt.Fprintf(buf, "\t( unzip -qDD -d '%s' '%s' 2>&1 | grep -v \"zipfile is empty\"; exit $${PIPESTATUS[0]} ) || \\\n", extraFiles.dir.String(), extraFiles.zip.String())
			fmt.Fprintf(buf, "\t  ( code=$$?; if [ $$code -ne 0 -a $$code -ne 1 ]; then exit $$code; fi )\n")
		}
		fmt.Fprintln(buf)
	}

	for _, symlink := range symlinks {
		fmt.Fprintf(buf, "%s:", symlink.to.String())
		if symlink.from != nil {
			// The symlink doesn't need updating when the target is modified, but we sometimes
			// have a dependency on a symlink to a binary instead of to the binary directly, and
			// the mtime of the symlink must be updated when the binary is modified, so use a
			// normal dependency here instead of an order-only dependency.
			fmt.Fprintf(buf, " %s", symlink.from.String())
		}
		for _, dep := range symlink.implicitDeps {
			fmt.Fprintf(buf, " %s", dep.String())
		}
		if len(symlink.orderOnlyDeps) > 0 {
			fmt.Fprintf(buf, " |")
		}
		for _, dep := range symlink.orderOnlyDeps {
			fmt.Fprintf(buf, " %s", dep.String())
		}
		fmt.Fprintln(buf)

		fromStr := ""
		if symlink.from != nil {
			rel, err := filepath.Rel(filepath.Dir(symlink.to.String()), symlink.from.String())
			if err != nil {
				panic(fmt.Errorf("failed to find relative path for symlink from %q to %q: %w",
					symlink.from.String(), symlink.to.String(), err))
			}
			fromStr = rel
		} else {
			fromStr = symlink.absFrom
		}

		fmt.Fprintln(buf, "\t@echo \"Symlink: $@\"")
		fmt.Fprintf(buf, "\trm -f $@ && ln -sfn %s $@", fromStr)
		fmt.Fprintln(buf)
		fmt.Fprintln(buf)
	}

	return buf.Bytes()
}

func (c *makeVarsContext) DeviceConfig() DeviceConfig {
	return DeviceConfig{c.Config().deviceConfig}
}

var ninjaDescaper = strings.NewReplacer("$$", "$")

func (c *makeVarsContext) Eval(ninjaStr string) (string, error) {
	s, err := c.SingletonContext.Eval(c.pctx, ninjaStr)
	if err != nil {
		return "", err
	}
	// SingletonContext.Eval returns an exapnded string that is valid for a ninja file, de-escape $$ to $ for use
	// in a Makefile
	return ninjaDescaper.Replace(s), nil
}

func (c *makeVarsContext) addVariableRaw(name, value string, strict, sort bool) {
	c.vars = append(c.vars, makeVarsVariable{
		name:   name,
		value:  value,
		strict: strict,
		sort:   sort,
	})
}

func (c *makeVarsContext) addVariable(name, ninjaStr string, strict, sort bool) {
	value, err := c.Eval(ninjaStr)
	if err != nil {
		c.SingletonContext.Errorf(err.Error())
	}
	c.addVariableRaw(name, value, strict, sort)
}

func (c *makeVarsContext) addPhony(name string, deps []string) {
	c.phonies = append(c.phonies, phony{name, deps})
}

func (c *makeVarsContext) addDist(goals []string, paths []string) {
	c.dists = append(c.dists, dist{
		goals: goals,
		paths: paths,
	})
}

func (c *makeVarsContext) Strict(name, ninjaStr string) {
	c.addVariable(name, ninjaStr, true, false)
}
func (c *makeVarsContext) StrictSorted(name, ninjaStr string) {
	c.addVariable(name, ninjaStr, true, true)
}
func (c *makeVarsContext) StrictRaw(name, value string) {
	c.addVariableRaw(name, value, true, false)
}

func (c *makeVarsContext) Check(name, ninjaStr string) {
	c.addVariable(name, ninjaStr, false, false)
}
func (c *makeVarsContext) CheckSorted(name, ninjaStr string) {
	c.addVariable(name, ninjaStr, false, true)
}
func (c *makeVarsContext) CheckRaw(name, value string) {
	c.addVariableRaw(name, value, false, false)
}

func (c *makeVarsContext) Phony(name string, deps ...Path) {
	c.addPhony(name, Paths(deps).Strings())
}

func (c *makeVarsContext) DistForGoal(goal string, paths ...Path) {
	c.DistForGoals([]string{goal}, paths...)
}

func (c *makeVarsContext) DistForGoalWithFilename(goal string, path Path, filename string) {
	c.DistForGoalsWithFilename([]string{goal}, path, filename)
}

func (c *makeVarsContext) DistForGoals(goals []string, paths ...Path) {
	c.addDist(goals, Paths(paths).Strings())
}

func (c *makeVarsContext) DistForGoalsWithFilename(goals []string, path Path, filename string) {
	c.addDist(goals, []string{path.String() + ":" + filename})
}