cmd/gomobile/build.go - mobile - Git at Google

 // Copyright 2015 The Go Authors.  All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.

 package main

 import (
 	"bytes"
 	"crypto/x509"
 	"encoding/pem"
 	"errors"
 	"fmt"
 	"go/build"
 	"io"
 	"io/ioutil"
 	"os"
 	"os/exec"
 	"path"
 	"path/filepath"
 	"strconv"
 	"strings"
 )

 var ctx = build.Default
 var pkg *build.Package
 var ndkccpath string
 var tmpdir string

 var cmdBuild = &command{
 	run:   runBuild,
 	Name:  "build",
 	Usage: "[package]",
 	Short: "compile android APK and/or iOS app",
 	Long: `
 Build compiles and encodes the app named by the import path.

 The named package must define a main function.

 If an AndroidManifest.xml is defined in the package directory, it is
 added to the APK file. Otherwise, a default manifest is generated.

 If the package directory contains an assets subdirectory, its contents
 are copied into the APK file.

 The -o flag specifies the output file name. If not specified, the
 output file name depends on the package built. The output file must end
 in '.apk'.

 The -v flag provides verbose output, including the list of packages built.

 These build flags are shared by the build, install, and test commands.
 For documentation, see 'go help build':
 	-a
 	-i
 	-n
 	-x
 	-tags 'tag list'
 `,
 }

 // TODO: -mobile

 func runBuild(cmd *command) error {
 	cwd, err := os.Getwd()
 	if err != nil {
 		panic(err)
 	}
 	args := cmd.flag.Args()

 	switch len(args) {
 	case 0:
 		pkg, err = ctx.ImportDir(cwd, build.ImportComment)
 	case 1:
 		pkg, err = ctx.Import(args[0], cwd, build.ImportComment)
 	default:
 		cmd.usage()
 		os.Exit(1)
 	}
 	if err != nil {
 		return err
 	}

 	if pkg.Name != "main" {
 		// Not an app, don't build a final package.
 		return gobuild(pkg.ImportPath, "")
 	}

 	// Building a program, make sure it is appropriate for mobile.
 	importsApp := false
 	for _, path := range pkg.Imports {
 		if path == "golang.org/x/mobile/app" {
 			importsApp = true
 			break
 		}
 	}
 	if !importsApp {
 		return fmt.Errorf(`%s does not import "golang.org/x/mobile/app"`, pkg.ImportPath)
 	}

 	if buildN {
 		tmpdir = "$WORK"
 	} else {
 		tmpdir, err = ioutil.TempDir("", "gobuildapk-work-")
 		if err != nil {
 			return err
 		}
 	}
 	defer removeAll(tmpdir)
 	if buildX {
 		fmt.Fprintln(os.Stderr, "WORK="+tmpdir)
 	}

 	libName := path.Base(pkg.ImportPath)
 	manifestData, err := ioutil.ReadFile(filepath.Join(pkg.Dir, "AndroidManifest.xml"))
 	if err != nil {
 		if !os.IsNotExist(err) {
 			return err
 		}
 		buf := new(bytes.Buffer)
 		buf.WriteString(`<?xml version="1.0" encoding="utf-8"?>`)
 		err := manifestTmpl.Execute(buf, manifestTmplData{
 			// TODO(crawshaw): a better package path.
 			JavaPkgPath: "org.golang.todo." + pkg.Name,
 			Name:        strings.ToUpper(pkg.Name[:1]) + pkg.Name[1:],
 			LibName:     libName,
 		})
 		if err != nil {
 			return err
 		}
 		manifestData = buf.Bytes()
 		if buildV {
 			fmt.Fprintf(os.Stderr, "generated AndroidManifest.xml:\n%s\n", manifestData)
 		}
 	} else {
 		libName, err = manifestLibName(manifestData)
 		if err != nil {
 			return err
 		}
 	}
 	libPath := filepath.Join(tmpdir, "lib"+libName+".so")

 	if err := gobuild(pkg.ImportPath, libPath); err != nil {
 		return err
 	}
 	block, _ := pem.Decode([]byte(debugCert))
 	if block == nil {
 		return errors.New("no debug cert")
 	}
 	privKey, err := x509.ParsePKCS1PrivateKey(block.Bytes)
 	if err != nil {
 		return err
 	}

 	if *buildO == "" {
 		*buildO = filepath.Base(pkg.Dir) + ".apk"
 	}
 	if !strings.HasSuffix(*buildO, ".apk") {
 		return fmt.Errorf("output file name %q does not end in '.apk'", *buildO)
 	}
 	out, err := os.Create(*buildO)
 	if err != nil {
 		return err
 	}

 	var apkw *Writer
 	if !buildN {
 		apkw = NewWriter(out, privKey)
 	}
 	apkwcreate := func(name string) (io.Writer, error) {
 		if buildV {
 			fmt.Fprintf(os.Stderr, "apk: %s\n", name)
 		}
 		if buildN {
 			return ioutil.Discard, nil
 		}
 		return apkw.Create(name)
 	}

 	w, err := apkwcreate("AndroidManifest.xml")
 	if err != nil {
 		return err
 	}
 	if _, err := w.Write(manifestData); err != nil {
 		return err
 	}

 	w, err = apkwcreate("lib/armeabi/lib" + libName + ".so")
 	if err != nil {
 		return err
 	}
 	if !buildN {
 		r, err := os.Open(libPath)
 		if err != nil {
 			return err
 		}
 		if _, err := io.Copy(w, r); err != nil {
 			return err
 		}
 	}

 	// Add any assets.
 	assetsDir := filepath.Join(pkg.Dir, "assets")
 	assetsDirExists := true
 	fi, err := os.Stat(assetsDir)
 	if err != nil {
 		if os.IsNotExist(err) {
 			assetsDirExists = false
 		} else {
 			return err
 		}
 	} else {
 		assetsDirExists = fi.IsDir()
 	}
 	if assetsDirExists {
 		filepath.Walk(assetsDir, func(path string, info os.FileInfo, err error) error {
 			if err != nil {
 				return err
 			}
 			if info.IsDir() {
 				return nil
 			}
 			name := "assets/" + path[len(assetsDir)+1:]
 			w, err := apkwcreate(name)
 			if err != nil {
 				return err
 			}
 			f, err := os.Open(path)
 			if err != nil {
 				return err
 			}
 			defer f.Close()
 			_, err = io.Copy(w, f)
 			return err
 		})
 	}

 	// TODO: add gdbserver to apk?

 	if buildN {
 		return nil
 	}
 	return apkw.Close()
 }

 var xout io.Writer = os.Stderr

 func printcmd(format string, args ...interface{}) {
 	cmd := fmt.Sprintf(format+"\n", args...)
 	if tmpdir != "" {
 		cmd = strings.Replace(cmd, tmpdir, "$WORK", -1)
 	}
 	if ndkccpath != "" {
 		cmd = strings.Replace(cmd, ndkccpath, "$NDKCCPATH", -1)
 	}
 	if goroot := goEnv("GOROOT"); goroot != "" {
 		cmd = strings.Replace(cmd, goroot, "$GOROOT", -1)
 	}
 	if env := os.Getenv("HOME"); env != "" {
 		cmd = strings.Replace(cmd, env, "$HOME", -1)
 	}
 	fmt.Fprint(xout, cmd)
 }

 // "Build flags", used by multiple commands.
 var (
 	buildA bool    // -a
 	buildI bool    // -i
 	buildN bool    // -n
 	buildV bool    // -v
 	buildX bool    // -x
 	buildO *string // -o
 )

 func addBuildFlags(cmd *command) {
 	cmd.flag.BoolVar(&buildA, "a", false, "")
 	cmd.flag.BoolVar(&buildI, "i", false, "")
 	cmd.flag.Var((*stringsFlag)(&ctx.BuildTags), "tags", "")
 }

 func addBuildFlagsNVX(cmd *command) {
 	cmd.flag.BoolVar(&buildN, "n", false, "")
 	cmd.flag.BoolVar(&buildV, "v", false, "")
 	cmd.flag.BoolVar(&buildX, "x", false, "")
 }

 // gobuild builds a package.
 // If libPath is specified then it builds as a shared library.
 func gobuild(src, libPath string) error {
 	version, err := goVersion()
 	if err != nil {
 		return err
 	}

 	gopath := goEnv("GOPATH")
 	gomobilepath := ""
 	for _, p := range filepath.SplitList(gopath) {
 		gomobilepath = filepath.Join(p, "pkg", "gomobile")
 		if _, err = os.Stat(gomobilepath); err == nil {
 			break
 		}
 	}
 	if err != nil || gomobilepath == "" {
 		return errors.New("android toolchain not installed, run:\n\tgomobile init")
 	}
 	verpath := filepath.Join(gomobilepath, "version")
 	installedVersion, err := ioutil.ReadFile(verpath)
 	if err != nil {
 		return errors.New("android toolchain partially installed, run:\n\tgomobile init")
 	}
 	if !bytes.Equal(installedVersion, version) {
 		return errors.New("android toolchain out of date, run:\n\tgomobile init")
 	}

 	ndkccpath = filepath.Join(gomobilepath, "android-"+ndkVersion)
 	ndkccbin := filepath.Join(ndkccpath, "arm", "bin")
 	if buildX {
 		fmt.Fprintln(os.Stderr, "NDKCCPATH="+ndkccpath)
 	}

 	gocmd := exec.Command(
 		`go`,
 		`build`,
 		`-tags=`+strconv.Quote(strings.Join(ctx.BuildTags, ",")),
 		`-toolexec=`+filepath.Join(ndkccbin, "toolexec"))
 	if buildV {
 		gocmd.Args = append(gocmd.Args, "-v")
 	}
 	if buildI {
 		gocmd.Args = append(gocmd.Args, "-i")
 	}
 	if buildX {
 		gocmd.Args = append(gocmd.Args, "-x")
 	}
 	if libPath == "" {
 		if *buildO != "" {
 			gocmd.Args = append(gocmd.Args, `-o`, *buildO)
 		}
 	} else {
 		gocmd.Args = append(gocmd.Args,
 			`-ldflags="-shared"`,
 			`-o`, libPath,
 		)
 	}

 	gocmd.Args = append(gocmd.Args, src)

 	gocmd.Stdout = os.Stdout
 	gocmd.Stderr = os.Stderr
 	gocmd.Env = []string{
 		`GOOS=android`,
 		`GOARCH=arm`,
 		`GOARM=7`,
 		`CGO_ENABLED=1`,
 		`CC=` + filepath.Join(ndkccbin, "arm-linux-androideabi-gcc"),
 		`CXX=` + filepath.Join(ndkccbin, "arm-linux-androideabi-g++"),
 		`GOGCCFLAGS="-fPIC -marm -pthread -fmessage-length=0"`,
 		`GOROOT=` + goEnv("GOROOT"),
 		`GOPATH=` + gopath,
 		`GOMOBILEPATH=` + ndkccbin, // for toolexec
 	}
 	if buildX {
 		printcmd("%s", strings.Join(gocmd.Env, " ")+" "+strings.Join(gocmd.Args, " "))
 	}
 	if !buildN {
 		if err := gocmd.Run(); err != nil {
 			return err
 		}
 	}
 	return nil
 }

 func init() {
 	buildO = cmdBuild.flag.String("o", "", "output file")
 	addBuildFlags(cmdBuild)
 	addBuildFlagsNVX(cmdBuild)

 	addBuildFlags(cmdInstall)
 	addBuildFlagsNVX(cmdInstall)

 	addBuildFlagsNVX(cmdInit)

 	addBuildFlags(cmdBind)
 	addBuildFlagsNVX(cmdBind)
 }

 // A random uninteresting private key.
 // Must be consistent across builds so newer app versions can be installed.
 const debugCert = `
 -----BEGIN RSA PRIVATE KEY-----
 MIIEowIBAAKCAQEAy6ItnWZJ8DpX9R5FdWbS9Kr1U8Z7mKgqNByGU7No99JUnmyu
 NQ6Uy6Nj0Gz3o3c0BXESECblOC13WdzjsH1Pi7/L9QV8jXOXX8cvkG5SJAyj6hcO
 LOapjDiN89NXjXtyv206JWYvRtpexyVrmHJgRAw3fiFI+m4g4Qop1CxcIF/EgYh7
 rYrqh4wbCM1OGaCleQWaOCXxZGm+J5YNKQcWpjZRrDrb35IZmlT0bK46CXUKvCqK
 x7YXHgfhC8ZsXCtsScKJVHs7gEsNxz7A0XoibFw6DoxtjKzUCktnT0w3wxdY7OTj
 9AR8mobFlM9W3yirX8TtwekWhDNTYEu8dwwykwIDAQABAoIBAA2hjpIhvcNR9H9Z
 BmdEecydAQ0ZlT5zy1dvrWI++UDVmIp+Ve8BSd6T0mOqV61elmHi3sWsBN4M1Rdz
 3N38lW2SajG9q0fAvBpSOBHgAKmfGv3Ziz5gNmtHgeEXfZ3f7J95zVGhlHqWtY95
 JsmuplkHxFMyITN6WcMWrhQg4A3enKLhJLlaGLJf9PeBrvVxHR1/txrfENd2iJBH
 FmxVGILL09fIIktJvoScbzVOneeWXj5vJGzWVhB17DHBbANGvVPdD5f+k/s5aooh
 hWAy/yLKocr294C4J+gkO5h2zjjjSGcmVHfrhlXQoEPX+iW1TGoF8BMtl4Llc+jw
 lKWKfpECgYEA9C428Z6CvAn+KJ2yhbAtuRo41kkOVoiQPtlPeRYs91Pq4+NBlfKO
 2nWLkyavVrLx4YQeCeaEU2Xoieo9msfLZGTVxgRlztylOUR+zz2FzDBYGicuUD3s
 EqC0Wv7tiX6dumpWyOcVVLmR9aKlOUzA9xemzIsWUwL3PpyONhKSq7kCgYEA1X2F
 f2jKjoOVzglhtuX4/SP9GxS4gRf9rOQ1Q8DzZhyH2LZ6Dnb1uEQvGhiqJTU8CXxb
 7odI0fgyNXq425Nlxc1Tu0G38TtJhwrx7HWHuFcbI/QpRtDYLWil8Zr7Q3BT9rdh
 moo4m937hLMvqOG9pyIbyjOEPK2WBCtKW5yabqsCgYEAu9DkUBr1Qf+Jr+IEU9I8
 iRkDSMeusJ6gHMd32pJVCfRRQvIlG1oTyTMKpafmzBAd/rFpjYHynFdRcutqcShm
 aJUq3QG68U9EAvWNeIhA5tr0mUEz3WKTt4xGzYsyWES8u4tZr3QXMzD9dOuinJ1N
 +4EEumXtSPKKDG3M8Qh+KnkCgYBUEVSTYmF5EynXc2xOCGsuy5AsrNEmzJqxDUBI
 SN/P0uZPmTOhJIkIIZlmrlW5xye4GIde+1jajeC/nG7U0EsgRAV31J4pWQ5QJigz
 0+g419wxIUFryGuIHhBSfpP472+w1G+T2mAGSLh1fdYDq7jx6oWE7xpghn5vb9id
 EKLjdwKBgBtz9mzbzutIfAW0Y8F23T60nKvQ0gibE92rnUbjPnw8HjL3AZLU05N+
 cSL5bhq0N5XHK77sscxW9vXjG0LJMXmFZPp9F6aV6ejkMIXyJ/Yz/EqeaJFwilTq
 Mc6xR47qkdzu0dQ1aPm4XD7AWDtIvPo/GG2DKOucLBbQc2cOWtKS
 -----END RSA PRIVATE KEY-----
 `
	// Copyright 2015 The Go Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style
	// license that can be found in the LICENSE file.

	package main

	import (
	"bytes"
	"crypto/x509"
	"encoding/pem"
	"errors"
	"fmt"
	"go/build"
	"io"
	"io/ioutil"
	"os"
	"os/exec"
	"path"
	"path/filepath"
	"strconv"
	"strings"
	)

	var ctx = build.Default
	var pkg *build.Package
	var ndkccpath string
	var tmpdir string

	var cmdBuild = &command{
	run: runBuild,
	Name: "build",
	Usage: "[package]",
	Short: "compile android APK and/or iOS app",
	Long: `
	Build compiles and encodes the app named by the import path.

	The named package must define a main function.

	If an AndroidManifest.xml is defined in the package directory, it is
	added to the APK file. Otherwise, a default manifest is generated.

	If the package directory contains an assets subdirectory, its contents
	are copied into the APK file.

	The -o flag specifies the output file name. If not specified, the
	output file name depends on the package built. The output file must end
	in '.apk'.

	The -v flag provides verbose output, including the list of packages built.

	These build flags are shared by the build, install, and test commands.
	For documentation, see 'go help build':
	-a
	-i
	-n
	-x
	-tags 'tag list'
	`,
	}

	// TODO: -mobile

	func runBuild(cmd *command) error {
	cwd, err := os.Getwd()
	if err != nil {
	panic(err)
	}
	args := cmd.flag.Args()

	switch len(args) {
	case 0:
	pkg, err = ctx.ImportDir(cwd, build.ImportComment)
	case 1:
	pkg, err = ctx.Import(args[0], cwd, build.ImportComment)
	default:
	cmd.usage()
	os.Exit(1)
	}
	if err != nil {
	return err
	}

	if pkg.Name != "main" {
	// Not an app, don't build a final package.
	return gobuild(pkg.ImportPath, "")
	}

	// Building a program, make sure it is appropriate for mobile.
	importsApp := false
	for _, path := range pkg.Imports {
	if path == "golang.org/x/mobile/app" {
	importsApp = true
	break
	}
	}
	if !importsApp {
	return fmt.Errorf(`%s does not import "golang.org/x/mobile/app"`, pkg.ImportPath)
	}

	if buildN {
	tmpdir = "$WORK"
	} else {
	tmpdir, err = ioutil.TempDir("", "gobuildapk-work-")
	if err != nil {
	return err
	}
	}
	defer removeAll(tmpdir)
	if buildX {
	fmt.Fprintln(os.Stderr, "WORK="+tmpdir)
	}

	libName := path.Base(pkg.ImportPath)
	manifestData, err := ioutil.ReadFile(filepath.Join(pkg.Dir, "AndroidManifest.xml"))
	if err != nil {
	if !os.IsNotExist(err) {
	return err
	}
	buf := new(bytes.Buffer)
	buf.WriteString(`<?xml version="1.0" encoding="utf-8"?>`)
	err := manifestTmpl.Execute(buf, manifestTmplData{
	// TODO(crawshaw): a better package path.
	JavaPkgPath: "org.golang.todo." + pkg.Name,
	Name: strings.ToUpper(pkg.Name[:1]) + pkg.Name[1:],
	LibName: libName,
	})
	if err != nil {
	return err
	}
	manifestData = buf.Bytes()
	if buildV {
	fmt.Fprintf(os.Stderr, "generated AndroidManifest.xml:\n%s\n", manifestData)
	}
	} else {
	libName, err = manifestLibName(manifestData)
	if err != nil {
	return err
	}
	}
	libPath := filepath.Join(tmpdir, "lib"+libName+".so")

	if err := gobuild(pkg.ImportPath, libPath); err != nil {
	return err
	}
	block, _ := pem.Decode([]byte(debugCert))
	if block == nil {
	return errors.New("no debug cert")
	}
	privKey, err := x509.ParsePKCS1PrivateKey(block.Bytes)
	if err != nil {
	return err
	}

	if *buildO == "" {
	*buildO = filepath.Base(pkg.Dir) + ".apk"
	}
	if !strings.HasSuffix(*buildO, ".apk") {
	return fmt.Errorf("output file name %q does not end in '.apk'", *buildO)
	}
	out, err := os.Create(*buildO)
	if err != nil {
	return err
	}

	var apkw *Writer
	if !buildN {
	apkw = NewWriter(out, privKey)
	}
	apkwcreate := func(name string) (io.Writer, error) {
	if buildV {
	fmt.Fprintf(os.Stderr, "apk: %s\n", name)
	}
	if buildN {
	return ioutil.Discard, nil
	}
	return apkw.Create(name)
	}

	w, err := apkwcreate("AndroidManifest.xml")
	if err != nil {
	return err
	}
	if _, err := w.Write(manifestData); err != nil {
	return err
	}

	w, err = apkwcreate("lib/armeabi/lib" + libName + ".so")
	if err != nil {
	return err
	}
	if !buildN {
	r, err := os.Open(libPath)
	if err != nil {
	return err
	}
	if _, err := io.Copy(w, r); err != nil {
	return err
	}
	}

	// Add any assets.
	assetsDir := filepath.Join(pkg.Dir, "assets")
	assetsDirExists := true
	fi, err := os.Stat(assetsDir)
	if err != nil {
	if os.IsNotExist(err) {
	assetsDirExists = false
	} else {
	return err
	}
	} else {
	assetsDirExists = fi.IsDir()
	}
	if assetsDirExists {
	filepath.Walk(assetsDir, func(path string, info os.FileInfo, err error) error {
	if err != nil {
	return err
	}
	if info.IsDir() {
	return nil
	}
	name := "assets/" + path[len(assetsDir)+1:]
	w, err := apkwcreate(name)
	if err != nil {
	return err
	}
	f, err := os.Open(path)
	if err != nil {
	return err
	}
	defer f.Close()
	_, err = io.Copy(w, f)
	return err
	})
	}

	// TODO: add gdbserver to apk?

	if buildN {
	return nil
	}
	return apkw.Close()
	}

	var xout io.Writer = os.Stderr

	func printcmd(format string, args ...interface{}) {
	cmd := fmt.Sprintf(format+"\n", args...)
	if tmpdir != "" {
	cmd = strings.Replace(cmd, tmpdir, "$WORK", -1)
	}
	if ndkccpath != "" {
	cmd = strings.Replace(cmd, ndkccpath, "$NDKCCPATH", -1)
	}
	if goroot := goEnv("GOROOT"); goroot != "" {
	cmd = strings.Replace(cmd, goroot, "$GOROOT", -1)
	}
	if env := os.Getenv("HOME"); env != "" {
	cmd = strings.Replace(cmd, env, "$HOME", -1)
	}
	fmt.Fprint(xout, cmd)
	}

	// "Build flags", used by multiple commands.
	var (
	buildA bool // -a
	buildI bool // -i
	buildN bool // -n
	buildV bool // -v
	buildX bool // -x
	buildO *string // -o
	)

	func addBuildFlags(cmd *command) {
	cmd.flag.BoolVar(&buildA, "a", false, "")
	cmd.flag.BoolVar(&buildI, "i", false, "")
	cmd.flag.Var((*stringsFlag)(&ctx.BuildTags), "tags", "")
	}

	func addBuildFlagsNVX(cmd *command) {
	cmd.flag.BoolVar(&buildN, "n", false, "")
	cmd.flag.BoolVar(&buildV, "v", false, "")
	cmd.flag.BoolVar(&buildX, "x", false, "")
	}

	// gobuild builds a package.
	// If libPath is specified then it builds as a shared library.
	func gobuild(src, libPath string) error {
	version, err := goVersion()
	if err != nil {
	return err
	}

	gopath := goEnv("GOPATH")
	gomobilepath := ""
	for _, p := range filepath.SplitList(gopath) {
	gomobilepath = filepath.Join(p, "pkg", "gomobile")
	if _, err = os.Stat(gomobilepath); err == nil {
	break
	}
	}
	if err != nil \|\| gomobilepath == "" {
	return errors.New("android toolchain not installed, run:\n\tgomobile init")
	}
	verpath := filepath.Join(gomobilepath, "version")
	installedVersion, err := ioutil.ReadFile(verpath)
	if err != nil {
	return errors.New("android toolchain partially installed, run:\n\tgomobile init")
	}
	if !bytes.Equal(installedVersion, version) {
	return errors.New("android toolchain out of date, run:\n\tgomobile init")
	}

	ndkccpath = filepath.Join(gomobilepath, "android-"+ndkVersion)
	ndkccbin := filepath.Join(ndkccpath, "arm", "bin")
	if buildX {
	fmt.Fprintln(os.Stderr, "NDKCCPATH="+ndkccpath)
	}

	gocmd := exec.Command(
	`go`,
	`build`,
	`-tags=`+strconv.Quote(strings.Join(ctx.BuildTags, ",")),
	`-toolexec=`+filepath.Join(ndkccbin, "toolexec"))
	if buildV {
	gocmd.Args = append(gocmd.Args, "-v")
	}
	if buildI {
	gocmd.Args = append(gocmd.Args, "-i")
	}
	if buildX {
	gocmd.Args = append(gocmd.Args, "-x")
	}
	if libPath == "" {
	if *buildO != "" {
	gocmd.Args = append(gocmd.Args, `-o`, *buildO)
	}
	} else {
	gocmd.Args = append(gocmd.Args,
	`-ldflags="-shared"`,
	`-o`, libPath,
	)
	}

	gocmd.Args = append(gocmd.Args, src)

	gocmd.Stdout = os.Stdout
	gocmd.Stderr = os.Stderr
	gocmd.Env = []string{
	`GOOS=android`,
	`GOARCH=arm`,
	`GOARM=7`,
	`CGO_ENABLED=1`,
	`CC=` + filepath.Join(ndkccbin, "arm-linux-androideabi-gcc"),
	`CXX=` + filepath.Join(ndkccbin, "arm-linux-androideabi-g++"),
	`GOGCCFLAGS="-fPIC -marm -pthread -fmessage-length=0"`,
	`GOROOT=` + goEnv("GOROOT"),
	`GOPATH=` + gopath,
	`GOMOBILEPATH=` + ndkccbin, // for toolexec
	}
	if buildX {
	printcmd("%s", strings.Join(gocmd.Env, " ")+" "+strings.Join(gocmd.Args, " "))
	}
	if !buildN {
	if err := gocmd.Run(); err != nil {
	return err
	}
	}
	return nil
	}

	func init() {
	buildO = cmdBuild.flag.String("o", "", "output file")
	addBuildFlags(cmdBuild)
	addBuildFlagsNVX(cmdBuild)

	addBuildFlags(cmdInstall)
	addBuildFlagsNVX(cmdInstall)

	addBuildFlagsNVX(cmdInit)

	addBuildFlags(cmdBind)
	addBuildFlagsNVX(cmdBind)
	}

	// A random uninteresting private key.
	// Must be consistent across builds so newer app versions can be installed.
	const debugCert = `
	-----BEGIN RSA PRIVATE KEY-----
	MIIEowIBAAKCAQEAy6ItnWZJ8DpX9R5FdWbS9Kr1U8Z7mKgqNByGU7No99JUnmyu
	NQ6Uy6Nj0Gz3o3c0BXESECblOC13WdzjsH1Pi7/L9QV8jXOXX8cvkG5SJAyj6hcO
	LOapjDiN89NXjXtyv206JWYvRtpexyVrmHJgRAw3fiFI+m4g4Qop1CxcIF/EgYh7
	rYrqh4wbCM1OGaCleQWaOCXxZGm+J5YNKQcWpjZRrDrb35IZmlT0bK46CXUKvCqK
	x7YXHgfhC8ZsXCtsScKJVHs7gEsNxz7A0XoibFw6DoxtjKzUCktnT0w3wxdY7OTj
	9AR8mobFlM9W3yirX8TtwekWhDNTYEu8dwwykwIDAQABAoIBAA2hjpIhvcNR9H9Z
	BmdEecydAQ0ZlT5zy1dvrWI++UDVmIp+Ve8BSd6T0mOqV61elmHi3sWsBN4M1Rdz
	3N38lW2SajG9q0fAvBpSOBHgAKmfGv3Ziz5gNmtHgeEXfZ3f7J95zVGhlHqWtY95
	JsmuplkHxFMyITN6WcMWrhQg4A3enKLhJLlaGLJf9PeBrvVxHR1/txrfENd2iJBH
	FmxVGILL09fIIktJvoScbzVOneeWXj5vJGzWVhB17DHBbANGvVPdD5f+k/s5aooh
	hWAy/yLKocr294C4J+gkO5h2zjjjSGcmVHfrhlXQoEPX+iW1TGoF8BMtl4Llc+jw
	lKWKfpECgYEA9C428Z6CvAn+KJ2yhbAtuRo41kkOVoiQPtlPeRYs91Pq4+NBlfKO
	2nWLkyavVrLx4YQeCeaEU2Xoieo9msfLZGTVxgRlztylOUR+zz2FzDBYGicuUD3s
	EqC0Wv7tiX6dumpWyOcVVLmR9aKlOUzA9xemzIsWUwL3PpyONhKSq7kCgYEA1X2F
	f2jKjoOVzglhtuX4/SP9GxS4gRf9rOQ1Q8DzZhyH2LZ6Dnb1uEQvGhiqJTU8CXxb
	7odI0fgyNXq425Nlxc1Tu0G38TtJhwrx7HWHuFcbI/QpRtDYLWil8Zr7Q3BT9rdh
	moo4m937hLMvqOG9pyIbyjOEPK2WBCtKW5yabqsCgYEAu9DkUBr1Qf+Jr+IEU9I8
	iRkDSMeusJ6gHMd32pJVCfRRQvIlG1oTyTMKpafmzBAd/rFpjYHynFdRcutqcShm
	aJUq3QG68U9EAvWNeIhA5tr0mUEz3WKTt4xGzYsyWES8u4tZr3QXMzD9dOuinJ1N
	+4EEumXtSPKKDG3M8Qh+KnkCgYBUEVSTYmF5EynXc2xOCGsuy5AsrNEmzJqxDUBI
	SN/P0uZPmTOhJIkIIZlmrlW5xye4GIde+1jajeC/nG7U0EsgRAV31J4pWQ5QJigz
	0+g419wxIUFryGuIHhBSfpP472+w1G+T2mAGSLh1fdYDq7jx6oWE7xpghn5vb9id
	EKLjdwKBgBtz9mzbzutIfAW0Y8F23T60nKvQ0gibE92rnUbjPnw8HjL3AZLU05N+
	cSL5bhq0N5XHK77sscxW9vXjG0LJMXmFZPp9F6aV6ejkMIXyJ/Yz/EqeaJFwilTq
	Mc6xR47qkdzu0dQ1aPm4XD7AWDtIvPo/GG2DKOucLBbQc2cOWtKS
	-----END RSA PRIVATE KEY-----
	`