cmd/gomobile/build_androidapp.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/base64"
 	"encoding/pem"
 	"errors"
 	"fmt"
 	"go/build"
 	"io"
 	"io/ioutil"
 	"log"
 	"os"
 	"path"
 	"path/filepath"
 	"strings"
 )

 func goAndroidBuild(pkg *build.Package, androidArchs []string) (map[string]bool, error) {
 	appName := path.Base(pkg.ImportPath)
 	libName := androidPkgName(appName)
 	manifestPath := filepath.Join(pkg.Dir, "AndroidManifest.xml")
 	manifestData, err := ioutil.ReadFile(manifestPath)
 	if err != nil {
 		if !os.IsNotExist(err) {
 			return nil, 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." + libName,
 			Name:        strings.Title(appName),
 			LibName:     libName,
 		})
 		if err != nil {
 			return nil, 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 nil, fmt.Errorf("error parsing %s: %v", manifestPath, err)
 		}
 	}

 	libFiles := []string{}
 	nmpkgs := make(map[string]map[string]bool) // map: arch -> extractPkgs' output

 	for _, arch := range androidArchs {
 		env := androidEnv[arch]
 		toolchain := ndk.Toolchain(arch)
 		libPath := "lib/" + toolchain.abi + "/lib" + libName + ".so"
 		libAbsPath := filepath.Join(tmpdir, libPath)
 		if err := mkdir(filepath.Dir(libAbsPath)); err != nil {
 			return nil, err
 		}
 		err = goBuild(
 			pkg.ImportPath,
 			env,
 			"-buildmode=c-shared",
 			"-o", libAbsPath,
 		)
 		if err != nil {
 			return nil, err
 		}
 		nmpkgs[arch], err = extractPkgs(toolchain.Path("nm"), libAbsPath)
 		if err != nil {
 			return nil, err
 		}
 		libFiles = append(libFiles, libPath)
 	}

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

 	if buildO == "" {
 		buildO = androidPkgName(filepath.Base(pkg.Dir)) + ".apk"
 	}
 	if !strings.HasSuffix(buildO, ".apk") {
 		return nil, fmt.Errorf("output file name %q does not end in '.apk'", buildO)
 	}
 	var out io.Writer
 	if !buildN {
 		f, err := os.Create(buildO)
 		if err != nil {
 			return nil, err
 		}
 		defer func() {
 			if cerr := f.Close(); err == nil {
 				err = cerr
 			}
 		}()
 		out = f
 	}

 	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)
 	}
 	apkwWriteFile := func(dst, src string) error {
 		w, err := apkwCreate(dst)
 		if err != nil {
 			return err
 		}
 		if !buildN {
 			f, err := os.Open(src)
 			if err != nil {
 				return err
 			}
 			defer f.Close()
 			if _, err := io.Copy(w, f); err != nil {
 				return err
 			}
 		}
 		return nil
 	}

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

 	w, err = apkwCreate("classes.dex")
 	if err != nil {
 		return nil, err
 	}
 	dexData, err := base64.StdEncoding.DecodeString(dexStr)
 	if err != nil {
 		log.Fatal("internal error bad dexStr: %v", err)
 	}
 	if _, err := w.Write(dexData); err != nil {
 		return nil, err
 	}

 	for _, libFile := range libFiles {
 		if err := apkwWriteFile(libFile, filepath.Join(tmpdir, libFile)); err != nil {
 			return nil, err
 		}
 	}

 	for _, arch := range androidArchs {
 		toolchain := ndk.Toolchain(arch)
 		if nmpkgs[arch]["golang.org/x/mobile/exp/audio/al"] {
 			dst := "lib/" + toolchain.abi + "/libopenal.so"
 			src := dst
 			if arch == "arm" {
 				src = "lib/armeabi/libopenal.so"
 			}
 			if err := apkwWriteFile(dst, filepath.Join(ndk.Root(), "openal/"+src)); err != nil {
 				return nil, 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 nil, err
 		}
 	} else {
 		assetsDirExists = fi.IsDir()
 	}
 	if assetsDirExists {
 		// if assets is a symlink, follow the symlink.
 		assetsDir, err = filepath.EvalSymlinks(assetsDir)
 		if err != nil {
 			return nil, err
 		}
 		err = filepath.Walk(assetsDir, func(path string, info os.FileInfo, err error) error {
 			if err != nil {
 				return err
 			}
 			if name := filepath.Base(path); strings.HasPrefix(name, ".") {
 				// Do not include the hidden files.
 				return nil
 			}
 			if info.IsDir() {
 				return nil
 			}
 			name := "assets/" + path[len(assetsDir)+1:]
 			return apkwWriteFile(name, path)
 		})
 		if err != nil {
 			return nil, fmt.Errorf("asset %v", err)
 		}
 	}

 	// TODO: add gdbserver to apk?

 	if !buildN {
 		if err := apkw.Close(); err != nil {
 			return nil, err
 		}
 	}

 	// TODO: return nmpkgs
 	return nmpkgs[androidArchs[0]], nil
 }

 // androidPkgName sanitizes the go package name to be acceptable as a android
 // package name part. The android package name convention is similar to the
 // java package name convention described in
 // https://docs.oracle.com/javase/specs/jls/se8/html/jls-6.html#jls-6.5.3.1
 // but not exactly same.
 func androidPkgName(name string) string {
 	var res []rune
 	for i, r := range name {
 		switch {
 		case 'a' <= r && r <= 'z', 'A' <= r && r <= 'Z':
 			res = append(res, r)
 		case '0' <= r && r <= '9':
 			if i == 0 {
 				panic(fmt.Sprintf("package name %q is not a valid go package name", name))
 			}
 			res = append(res, r)
 		default:
 			res = append(res, '_')
 		}
 	}
 	if len(res) == 0 || res[0] == '_' {
 		// Android does not seem to allow the package part starting with _.
 		res = append([]rune{'g', 'o'}, res...)
 	}
 	s := string(res)
 	// Look for Java keywords that are not Go keywords, and avoid using
 	// them as a package name.
 	//
 	// This is not a problem for normal Go identifiers as we only expose
 	// exported symbols. The upper case first letter saves everything
 	// from accidentally matching except for the package name.
 	//
 	// Note that basic type names (like int) are not keywords in Go.
 	switch s {
 	case "abstract", "assert", "boolean", "byte", "catch", "char", "class",
 		"do", "double", "enum", "extends", "final", "finally", "float",
 		"implements", "instanceof", "int", "long", "native", "private",
 		"protected", "public", "short", "static", "strictfp", "super",
 		"synchronized", "this", "throw", "throws", "transient", "try",
 		"void", "volatile", "while":
 		s += "_"
 	}
 	return s
 }

 // 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/base64"
	"encoding/pem"
	"errors"
	"fmt"
	"go/build"
	"io"
	"io/ioutil"
	"log"
	"os"
	"path"
	"path/filepath"
	"strings"
	)

	func goAndroidBuild(pkg *build.Package, androidArchs []string) (map[string]bool, error) {
	appName := path.Base(pkg.ImportPath)
	libName := androidPkgName(appName)
	manifestPath := filepath.Join(pkg.Dir, "AndroidManifest.xml")
	manifestData, err := ioutil.ReadFile(manifestPath)
	if err != nil {
	if !os.IsNotExist(err) {
	return nil, 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." + libName,
	Name: strings.Title(appName),
	LibName: libName,
	})
	if err != nil {
	return nil, 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 nil, fmt.Errorf("error parsing %s: %v", manifestPath, err)
	}
	}

	libFiles := []string{}
	nmpkgs := make(map[string]map[string]bool) // map: arch -> extractPkgs' output

	for _, arch := range androidArchs {
	env := androidEnv[arch]
	toolchain := ndk.Toolchain(arch)
	libPath := "lib/" + toolchain.abi + "/lib" + libName + ".so"
	libAbsPath := filepath.Join(tmpdir, libPath)
	if err := mkdir(filepath.Dir(libAbsPath)); err != nil {
	return nil, err
	}
	err = goBuild(
	pkg.ImportPath,
	env,
	"-buildmode=c-shared",
	"-o", libAbsPath,
	)
	if err != nil {
	return nil, err
	}
	nmpkgs[arch], err = extractPkgs(toolchain.Path("nm"), libAbsPath)
	if err != nil {
	return nil, err
	}
	libFiles = append(libFiles, libPath)
	}

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

	if buildO == "" {
	buildO = androidPkgName(filepath.Base(pkg.Dir)) + ".apk"
	}
	if !strings.HasSuffix(buildO, ".apk") {
	return nil, fmt.Errorf("output file name %q does not end in '.apk'", buildO)
	}
	var out io.Writer
	if !buildN {
	f, err := os.Create(buildO)
	if err != nil {
	return nil, err
	}
	defer func() {
	if cerr := f.Close(); err == nil {
	err = cerr
	}
	}()
	out = f
	}

	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)
	}
	apkwWriteFile := func(dst, src string) error {
	w, err := apkwCreate(dst)
	if err != nil {
	return err
	}
	if !buildN {
	f, err := os.Open(src)
	if err != nil {
	return err
	}
	defer f.Close()
	if _, err := io.Copy(w, f); err != nil {
	return err
	}
	}
	return nil
	}

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

	w, err = apkwCreate("classes.dex")
	if err != nil {
	return nil, err
	}
	dexData, err := base64.StdEncoding.DecodeString(dexStr)
	if err != nil {
	log.Fatal("internal error bad dexStr: %v", err)
	}
	if _, err := w.Write(dexData); err != nil {
	return nil, err
	}

	for _, libFile := range libFiles {
	if err := apkwWriteFile(libFile, filepath.Join(tmpdir, libFile)); err != nil {
	return nil, err
	}
	}

	for _, arch := range androidArchs {
	toolchain := ndk.Toolchain(arch)
	if nmpkgs[arch]["golang.org/x/mobile/exp/audio/al"] {
	dst := "lib/" + toolchain.abi + "/libopenal.so"
	src := dst
	if arch == "arm" {
	src = "lib/armeabi/libopenal.so"
	}
	if err := apkwWriteFile(dst, filepath.Join(ndk.Root(), "openal/"+src)); err != nil {
	return nil, 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 nil, err
	}
	} else {
	assetsDirExists = fi.IsDir()
	}
	if assetsDirExists {
	// if assets is a symlink, follow the symlink.
	assetsDir, err = filepath.EvalSymlinks(assetsDir)
	if err != nil {
	return nil, err
	}
	err = filepath.Walk(assetsDir, func(path string, info os.FileInfo, err error) error {
	if err != nil {
	return err
	}
	if name := filepath.Base(path); strings.HasPrefix(name, ".") {
	// Do not include the hidden files.
	return nil
	}
	if info.IsDir() {
	return nil
	}
	name := "assets/" + path[len(assetsDir)+1:]
	return apkwWriteFile(name, path)
	})
	if err != nil {
	return nil, fmt.Errorf("asset %v", err)
	}
	}

	// TODO: add gdbserver to apk?

	if !buildN {
	if err := apkw.Close(); err != nil {
	return nil, err
	}
	}

	// TODO: return nmpkgs
	return nmpkgs[androidArchs[0]], nil
	}

	// androidPkgName sanitizes the go package name to be acceptable as a android
	// package name part. The android package name convention is similar to the
	// java package name convention described in
	// https://docs.oracle.com/javase/specs/jls/se8/html/jls-6.html#jls-6.5.3.1
	// but not exactly same.
	func androidPkgName(name string) string {
	var res []rune
	for i, r := range name {
	switch {
	case 'a' <= r && r <= 'z', 'A' <= r && r <= 'Z':
	res = append(res, r)
	case '0' <= r && r <= '9':
	if i == 0 {
	panic(fmt.Sprintf("package name %q is not a valid go package name", name))
	}
	res = append(res, r)
	default:
	res = append(res, '_')
	}
	}
	if len(res) == 0 \|\| res[0] == '_' {
	// Android does not seem to allow the package part starting with _.
	res = append([]rune{'g', 'o'}, res...)
	}
	s := string(res)
	// Look for Java keywords that are not Go keywords, and avoid using
	// them as a package name.
	//
	// This is not a problem for normal Go identifiers as we only expose
	// exported symbols. The upper case first letter saves everything
	// from accidentally matching except for the package name.
	//
	// Note that basic type names (like int) are not keywords in Go.
	switch s {
	case "abstract", "assert", "boolean", "byte", "catch", "char", "class",
	"do", "double", "enum", "extends", "final", "finally", "float",
	"implements", "instanceof", "int", "long", "native", "private",
	"protected", "public", "short", "static", "strictfp", "super",
	"synchronized", "this", "throw", "throws", "transient", "try",
	"void", "volatile", "while":
	s += "_"
	}
	return s
	}

	// 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-----
	`