/
bind.go
755 lines (701 loc) · 19.3 KB
/
bind.go
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// 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"
"errors"
"fmt"
"go/ast"
"go/build"
"go/importer"
"go/parser"
"go/token"
"go/types"
"io"
"io/ioutil"
"os"
"path"
"path/filepath"
"strings"
"golang.org/x/mobile/bind"
"golang.org/x/mobile/internal/importers"
"golang.org/x/mobile/internal/importers/java"
"golang.org/x/mobile/internal/importers/objc"
)
// ctx, pkg, tmpdir in build.go
var cmdBind = &command{
run: runBind,
Name: "bind",
Usage: "[-target android|ios] [-bootclasspath <path>] [-classpath <path>] [-o output] [build flags] [package]",
Short: "build a library for Android and iOS",
Long: `
Bind generates language bindings for the package named by the import
path, and compiles a library for the named target system.
The -target flag takes a target system name, either android (the
default) or ios.
For -target android, the bind command produces an AAR (Android ARchive)
file that archives the precompiled Java API stub classes, the compiled
shared libraries, and all asset files in the /assets subdirectory under
the package directory. The output is named '<package_name>.aar' by
default. This AAR file is commonly used for binary distribution of an
Android library project and most Android IDEs support AAR import. For
example, in Android Studio (1.2+), an AAR file can be imported using
the module import wizard (File > New > New Module > Import .JAR or
.AAR package), and setting it as a new dependency
(File > Project Structure > Dependencies). This requires 'javac'
(version 1.7+) and Android SDK (API level 15 or newer) to build the
library for Android. The environment variable ANDROID_HOME must be set
to the path to Android SDK. The generated Java class is in the java
package 'go.<package_name>' unless -javapkg flag is specified.
By default, -target=android builds shared libraries for all supported
instruction sets (arm, arm64, 386, amd64). A subset of instruction sets
can be selected by specifying target type with the architecture name. E.g.,
-target=android/arm,android/386.
For -target ios, gomobile must be run on an OS X machine with Xcode
installed. Support is not complete. The generated Objective-C types
are prefixed with 'Go' unless the -prefix flag is provided.
For -target android, the -bootclasspath and -classpath flags are used to
control the bootstrap classpath and the classpath for Go wrappers to Java
classes.
The -v flag provides verbose output, including the list of packages built.
The build flags -a, -n, -x, -gcflags, -ldflags, -tags, and -work
are shared with the build command. For documentation, see 'go help build'.
`,
}
func runBind(cmd *command) error {
cleanup, err := buildEnvInit()
if err != nil {
return err
}
defer cleanup()
args := cmd.flag.Args()
targetOS, targetArchs, err := parseBuildTarget(buildTarget)
if err != nil {
return fmt.Errorf(`invalid -target=%q: %v`, buildTarget, err)
}
ctx.GOARCH = "arm"
ctx.GOOS = targetOS
if ctx.GOOS == "darwin" {
ctx.BuildTags = append(ctx.BuildTags, "ios")
}
if bindJavaPkg != "" && ctx.GOOS != "android" {
return fmt.Errorf("-javapkg is supported only for android target")
}
if bindPrefix != "" && ctx.GOOS != "darwin" {
return fmt.Errorf("-prefix is supported only for ios target")
}
if ctx.GOOS == "android" && ndkRoot == "" {
return errors.New("no Android NDK path is set. Please run gomobile init with the ndk-bundle installed through the Android SDK manager or with the -ndk flag set.")
}
var pkgs []*build.Package
switch len(args) {
case 0:
pkgs = make([]*build.Package, 1)
pkgs[0], err = ctx.ImportDir(cwd, build.ImportComment)
default:
pkgs, err = importPackages(args)
}
if err != nil {
return err
}
// check if any of the package is main
for _, pkg := range pkgs {
if pkg.Name == "main" {
return fmt.Errorf("binding 'main' package (%s) is not supported", pkg.ImportComment)
}
}
switch targetOS {
case "android":
return goAndroidBind(pkgs, targetArchs)
case "darwin":
// TODO: use targetArchs?
return goIOSBind(pkgs)
default:
return fmt.Errorf(`invalid -target=%q`, buildTarget)
}
}
func importPackages(args []string) ([]*build.Package, error) {
pkgs := make([]*build.Package, len(args))
for i, a := range args {
a = path.Clean(a)
var err error
if pkgs[i], err = ctx.Import(a, cwd, build.ImportComment); err != nil {
return nil, fmt.Errorf("package %q: %v", a, err)
}
}
return pkgs, nil
}
var (
bindPrefix string // -prefix
bindJavaPkg string // -javapkg
bindClasspath string // -classpath
bindBootClasspath string // -bootclasspath
)
func init() {
// bind command specific commands.
cmdBind.flag.StringVar(&bindJavaPkg, "javapkg", "",
"specifies custom Java package path prefix. Valid only with -target=android.")
cmdBind.flag.StringVar(&bindPrefix, "prefix", "",
"custom Objective-C name prefix. Valid only with -target=ios.")
cmdBind.flag.StringVar(&bindClasspath, "classpath", "", "The classpath for imported Java classes. Valid only with -target=android.")
cmdBind.flag.StringVar(&bindBootClasspath, "bootclasspath", "", "The bootstrap classpath for imported Java classes. Valid only with -target=android.")
}
type binder struct {
files []*ast.File
fset *token.FileSet
pkgs []*types.Package
}
func (b *binder) GenGoSupport(outdir string) error {
bindPkg, err := ctx.Import("golang.org/x/mobile/bind", "", build.FindOnly)
if err != nil {
return err
}
return copyFile(filepath.Join(outdir, "seq.go"), filepath.Join(bindPkg.Dir, "seq.go.support"))
}
func (b *binder) GenObjcSupport(outdir string) error {
objcPkg, err := ctx.Import("golang.org/x/mobile/bind/objc", "", build.FindOnly)
if err != nil {
return err
}
if err := copyFile(filepath.Join(outdir, "seq_darwin.m"), filepath.Join(objcPkg.Dir, "seq_darwin.m.support")); err != nil {
return err
}
if err := copyFile(filepath.Join(outdir, "seq_darwin.go"), filepath.Join(objcPkg.Dir, "seq_darwin.go.support")); err != nil {
return err
}
if err := copyFile(filepath.Join(outdir, "ref.h"), filepath.Join(objcPkg.Dir, "ref.h")); err != nil {
return err
}
return copyFile(filepath.Join(outdir, "seq.h"), filepath.Join(objcPkg.Dir, "seq.h"))
}
func (b *binder) GenObjc(pkg *types.Package, files []*ast.File, allPkg []*types.Package, outdir string, wrappers []*objc.Named) (string, error) {
if pkg == nil {
bindPrefix = ""
}
pkgName := ""
pkgPath := ""
if pkg != nil {
pkgName = pkg.Name()
pkgPath = pkg.Path()
} else {
pkgName = "universe"
}
bindOption := "-lang=objc"
if bindPrefix != "" {
bindOption += fmt.Sprintf(" -prefix=%q", bindPrefix)
}
fileBase := bindPrefix + strings.Title(pkgName)
mfile := filepath.Join(outdir, fileBase+".m")
hfile := filepath.Join(outdir, fileBase+".objc.h")
gohfile := filepath.Join(outdir, pkgName+".h")
var buf bytes.Buffer
g := &bind.ObjcGen{
Generator: &bind.Generator{
Printer: &bind.Printer{Buf: &buf, IndentEach: []byte("\t")},
Fset: b.fset,
AllPkg: allPkg,
Pkg: pkg,
Files: files,
},
Prefix: bindPrefix,
}
g.Init(wrappers)
generate := func(w io.Writer) error {
if buildX {
printcmd("gobind %s -outdir=%s %s", bindOption, outdir, pkgPath)
}
if buildN {
return nil
}
buf.Reset()
if err := g.GenM(); err != nil {
return err
}
_, err := io.Copy(w, &buf)
return err
}
if err := writeFile(mfile, generate); err != nil {
return "", err
}
generate = func(w io.Writer) error {
if buildN {
return nil
}
buf.Reset()
if err := g.GenH(); err != nil {
return err
}
_, err := io.Copy(w, &buf)
return err
}
if err := writeFile(hfile, generate); err != nil {
return "", err
}
generate = func(w io.Writer) error {
if buildN {
return nil
}
buf.Reset()
if err := g.GenGoH(); err != nil {
return err
}
_, err := io.Copy(w, &buf)
return err
}
if err := writeFile(gohfile, generate); err != nil {
return "", err
}
return fileBase, nil
}
func (b *binder) GenJavaSupport(outdir string) error {
javaPkg, err := ctx.Import("golang.org/x/mobile/bind/java", "", build.FindOnly)
if err != nil {
return err
}
if err := copyFile(filepath.Join(outdir, "seq_android.go"), filepath.Join(javaPkg.Dir, "seq_android.go.support")); err != nil {
return err
}
if err := copyFile(filepath.Join(outdir, "seq_android.c"), filepath.Join(javaPkg.Dir, "seq_android.c.support")); err != nil {
return err
}
return copyFile(filepath.Join(outdir, "seq.h"), filepath.Join(javaPkg.Dir, "seq.h"))
}
func bootClasspath() (string, error) {
if bindBootClasspath != "" {
return bindBootClasspath, nil
}
apiPath, err := androidAPIPath()
if err != nil {
return "", err
}
return filepath.Join(apiPath, "android.jar"), nil
}
func GenObjcWrappers(pkgs []*build.Package, srcDir, pkgGen string) ([]*objc.Named, error) {
refs, err := importers.AnalyzePackages(pkgs, "ObjC/")
if err != nil {
return nil, err
}
types, err := objc.Import(refs)
if err != nil {
return nil, err
}
var buf bytes.Buffer
g := &bind.ObjcWrapper{
Printer: &bind.Printer{
IndentEach: []byte("\t"),
Buf: &buf,
},
}
var genNames []string
for _, emb := range refs.Embedders {
genNames = append(genNames, emb.Name)
}
g.Init(types, genNames)
for i, name := range g.Packages() {
pkgDir := filepath.Join(pkgGen, "src", "ObjC", name)
if err := os.MkdirAll(pkgDir, 0700); err != nil {
return nil, err
}
pkgFile := filepath.Join(pkgDir, "package.go")
generate := func(w io.Writer) error {
if buildN {
return nil
}
buf.Reset()
g.GenPackage(i)
_, err := io.Copy(w, &buf)
return err
}
if err := writeFile(pkgFile, generate); err != nil {
return nil, fmt.Errorf("failed to create the ObjC wrapper package %s: %v", name, err)
}
}
generate := func(w io.Writer) error {
if buildN {
return nil
}
buf.Reset()
g.GenGo()
_, err := io.Copy(w, &buf)
return err
}
if err := writeFile(filepath.Join(srcDir, "interfaces.go"), generate); err != nil {
return nil, fmt.Errorf("failed to create the ObjC wrapper Go file: %v", err)
}
generate = func(w io.Writer) error {
if buildN {
return nil
}
buf.Reset()
g.GenInterfaces()
_, err := io.Copy(w, &buf)
return err
}
if err := writeFile(filepath.Join(pkgGen, "src", "ObjC", "interfaces.go"), generate); err != nil {
return nil, fmt.Errorf("failed to create the ObjC wrapper Go file: %v", err)
}
generate = func(w io.Writer) error {
if buildN {
return nil
}
buf.Reset()
g.GenH()
_, err := io.Copy(w, &buf)
return err
}
if err := writeFile(filepath.Join(srcDir, "interfaces.h"), generate); err != nil {
return nil, fmt.Errorf("failed to create the ObjC wrapper header file: %v", err)
}
generate = func(w io.Writer) error {
if buildN {
return nil
}
buf.Reset()
g.GenM()
_, err := io.Copy(w, &buf)
return err
}
if err := writeFile(filepath.Join(srcDir, "interfaces.m"), generate); err != nil {
return nil, fmt.Errorf("failed to create the Java classes ObjC file: %v", err)
}
return types, nil
}
func GenClasses(pkgs []*build.Package, srcDir, jpkgSrc string) ([]*java.Class, error) {
refs, err := importers.AnalyzePackages(pkgs, "Java/")
if err != nil {
return nil, err
}
bClspath, err := bootClasspath()
if err != nil {
return nil, err
}
imp := &java.Importer{
Bootclasspath: bClspath,
Classpath: bindClasspath,
JavaPkg: bindJavaPkg,
}
classes, err := imp.Import(refs)
if err != nil {
return nil, err
}
var buf bytes.Buffer
g := &bind.ClassGen{
JavaPkg: bindJavaPkg,
Printer: &bind.Printer{
IndentEach: []byte("\t"),
Buf: &buf,
},
}
g.Init(classes, refs.Embedders)
for i, jpkg := range g.Packages() {
pkgDir := filepath.Join(jpkgSrc, "src", "Java", jpkg)
if err := os.MkdirAll(pkgDir, 0700); err != nil {
return nil, err
}
pkgFile := filepath.Join(pkgDir, "package.go")
generate := func(w io.Writer) error {
if buildN {
return nil
}
buf.Reset()
g.GenPackage(i)
_, err := io.Copy(w, &buf)
return err
}
if err := writeFile(pkgFile, generate); err != nil {
return nil, fmt.Errorf("failed to create the Java wrapper package %s: %v", jpkg, err)
}
}
generate := func(w io.Writer) error {
if buildN {
return nil
}
buf.Reset()
g.GenGo()
_, err := io.Copy(w, &buf)
return err
}
if err := writeFile(filepath.Join(srcDir, "classes.go"), generate); err != nil {
return nil, fmt.Errorf("failed to create the Java classes Go file: %v", err)
}
generate = func(w io.Writer) error {
if buildN {
return nil
}
buf.Reset()
g.GenH()
_, err := io.Copy(w, &buf)
return err
}
if err := writeFile(filepath.Join(srcDir, "classes.h"), generate); err != nil {
return nil, fmt.Errorf("failed to create the Java classes header file: %v", err)
}
generate = func(w io.Writer) error {
if buildN {
return nil
}
buf.Reset()
g.GenC()
_, err := io.Copy(w, &buf)
return err
}
if err := writeFile(filepath.Join(srcDir, "classes.c"), generate); err != nil {
return nil, fmt.Errorf("failed to create the Java classes C file: %v", err)
}
generate = func(w io.Writer) error {
if buildN {
return nil
}
buf.Reset()
g.GenInterfaces()
_, err := io.Copy(w, &buf)
return err
}
if err := writeFile(filepath.Join(jpkgSrc, "src", "Java", "interfaces.go"), generate); err != nil {
return nil, fmt.Errorf("failed to create the Java classes interfaces file: %v", err)
}
return classes, nil
}
func (b *binder) GenJava(pkg *types.Package, files []*ast.File, allPkg []*types.Package, classes []*java.Class, outdir, androidDir string) error {
jpkgname := bind.JavaPkgName(bindJavaPkg, pkg)
javadir := filepath.Join(androidDir, strings.Replace(jpkgname, ".", "/", -1))
var className string
pkgName := ""
pkgPath := ""
if pkg != nil {
className = strings.Title(pkg.Name())
pkgName = pkg.Name()
pkgPath = pkg.Path()
} else {
pkgName = "universe"
className = "Universe"
}
javaFile := filepath.Join(javadir, className+".java")
cFile := filepath.Join(outdir, "java_"+pkgName+".c")
hFile := filepath.Join(outdir, pkgName+".h")
bindOption := "-lang=java"
if bindJavaPkg != "" {
bindOption += " -javapkg=" + bindJavaPkg
}
var buf bytes.Buffer
g := &bind.JavaGen{
JavaPkg: bindJavaPkg,
Generator: &bind.Generator{
Printer: &bind.Printer{Buf: &buf, IndentEach: []byte(" ")},
Fset: b.fset,
AllPkg: allPkg,
Pkg: pkg,
Files: files,
},
}
g.Init(classes)
generate := func(w io.Writer) error {
if buildX {
printcmd("gobind %s -outdir=%s %s", bindOption, javadir, pkgPath)
}
if buildN {
return nil
}
buf.Reset()
if err := g.GenJava(); err != nil {
return err
}
_, err := io.Copy(w, &buf)
return err
}
if err := writeFile(javaFile, generate); err != nil {
return err
}
for i, name := range g.ClassNames() {
generate := func(w io.Writer) error {
if buildN {
return nil
}
buf.Reset()
if err := g.GenClass(i); err != nil {
return err
}
_, err := io.Copy(w, &buf)
return err
}
classFile := filepath.Join(javadir, name+".java")
if err := writeFile(classFile, generate); err != nil {
return err
}
}
generate = func(w io.Writer) error {
if buildN {
return nil
}
buf.Reset()
if err := g.GenC(); err != nil {
return err
}
_, err := io.Copy(w, &buf)
return err
}
if err := writeFile(cFile, generate); err != nil {
return err
}
generate = func(w io.Writer) error {
if buildN {
return nil
}
buf.Reset()
if err := g.GenH(); err != nil {
return err
}
_, err := io.Copy(w, &buf)
return err
}
return writeFile(hFile, generate)
}
func (b *binder) GenGo(pkg *types.Package, allPkg []*types.Package, outdir string) error {
pkgName := "go_"
pkgPath := ""
if pkg != nil {
pkgName += pkg.Name()
pkgPath = pkg.Path()
}
goFile := filepath.Join(outdir, pkgName+"main.go")
generate := func(w io.Writer) error {
if buildX {
printcmd("gobind -lang=go -outdir=%s %s", outdir, pkgPath)
}
if buildN {
return nil
}
conf := &bind.GeneratorConfig{
Writer: w,
Fset: b.fset,
Pkg: pkg,
AllPkg: allPkg,
}
return bind.GenGo(conf)
}
if err := writeFile(goFile, generate); err != nil {
return err
}
return nil
}
func copyFile(dst, src string) error {
if buildX {
printcmd("cp %s %s", src, dst)
}
return writeFile(dst, func(w io.Writer) error {
if buildN {
return nil
}
f, err := os.Open(src)
if err != nil {
return err
}
defer f.Close()
if _, err := io.Copy(w, f); err != nil {
return fmt.Errorf("cp %s %s failed: %v", src, dst, err)
}
return nil
})
}
func writeFile(filename string, generate func(io.Writer) error) error {
if buildV {
fmt.Fprintf(os.Stderr, "write %s\n", filename)
}
err := mkdir(filepath.Dir(filename))
if err != nil {
return err
}
if buildN {
return generate(ioutil.Discard)
}
f, err := os.Create(filename)
if err != nil {
return err
}
defer func() {
if cerr := f.Close(); err == nil {
err = cerr
}
}()
return generate(f)
}
func loadExportData(pkgs []*build.Package, env []string, args ...string) ([]*types.Package, error) {
// Compile the package. This will produce good errors if the package
// doesn't typecheck for some reason, and is a necessary step to
// building the final output anyway.
paths := make([]string, len(pkgs))
for i, p := range pkgs {
paths[i] = p.ImportPath
}
if err := goInstall(paths, env, args...); err != nil {
return nil, err
}
goos, goarch := getenv(env, "GOOS"), getenv(env, "GOARCH")
// Assemble a fake GOPATH and trick go/importer into using it.
// Ideally the importer package would let us provide this to
// it somehow, but this works with what's in Go 1.5 today and
// gives us access to the gcimporter package without us having
// to make a copy of it.
fakegopath := filepath.Join(tmpdir, "fakegopath")
if err := removeAll(fakegopath); err != nil {
return nil, err
}
if err := mkdir(filepath.Join(fakegopath, "pkg")); err != nil {
return nil, err
}
typePkgs := make([]*types.Package, len(pkgs))
imp := importer.Default()
for i, p := range pkgs {
importPath := p.ImportPath
src := filepath.Join(pkgdir(env), importPath+".a")
dst := filepath.Join(fakegopath, "pkg/"+goos+"_"+goarch+"/"+importPath+".a")
if err := copyFile(dst, src); err != nil {
return nil, err
}
if buildN {
typePkgs[i] = types.NewPackage(importPath, path.Base(importPath))
continue
}
oldDefault := build.Default
build.Default = ctx // copy
build.Default.GOARCH = goarch
build.Default.GOPATH = fakegopath
p, err := imp.Import(importPath)
build.Default = oldDefault
if err != nil {
return nil, err
}
typePkgs[i] = p
}
return typePkgs, nil
}
func parse(pkgs []*build.Package) ([][]*ast.File, error) {
fset := token.NewFileSet()
var astPkgs [][]*ast.File
for _, pkg := range pkgs {
fileNames := append(append([]string{}, pkg.GoFiles...), pkg.CgoFiles...)
var files []*ast.File
for _, name := range fileNames {
f, err := parser.ParseFile(fset, filepath.Join(pkg.Dir, name), nil, parser.ParseComments)
if err != nil {
return nil, err
}
files = append(files, f)
}
astPkgs = append(astPkgs, files)
}
return astPkgs, nil
}
func newBinder(pkgs []*types.Package) (*binder, error) {
for _, pkg := range pkgs {
if pkg.Name() == "main" {
return nil, fmt.Errorf("package %q (%q): can only bind a library package", pkg.Name(), pkg.Path())
}
}
b := &binder{
fset: token.NewFileSet(),
pkgs: pkgs,
}
return b, nil
}