Permalink
Switch branches/tags
Nothing to show
Find file Copy path
207 lines (175 sloc) 4.29 KB
// 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
//go:generate gomobile help documentation doc.go
import (
"bufio"
"bytes"
"errors"
"flag"
"fmt"
"html/template"
"io"
"io/ioutil"
"log"
"os"
"os/exec"
"unicode"
"unicode/utf8"
)
var (
gomobileName = "gomobile"
goVersionOut = []byte(nil)
)
func printUsage(w io.Writer) {
bufw := bufio.NewWriter(w)
if err := usageTmpl.Execute(bufw, commands); err != nil {
panic(err)
}
bufw.Flush()
}
func main() {
gomobileName = os.Args[0]
flag.Usage = func() {
printUsage(os.Stderr)
os.Exit(2)
}
flag.Parse()
log.SetFlags(0)
args := flag.Args()
if len(args) < 1 {
flag.Usage()
}
if args[0] == "help" {
if len(args) == 3 && args[1] == "documentation" {
helpDocumentation(args[2])
return
}
help(args[1:])
return
}
if err := determineGoVersion(); err != nil {
fmt.Fprintf(os.Stderr, "%s: %v\n", gomobileName, err)
os.Exit(1)
}
for _, cmd := range commands {
if cmd.Name == args[0] {
cmd.flag.Usage = func() {
cmd.usage()
os.Exit(1)
}
cmd.flag.Parse(args[1:])
if err := cmd.run(cmd); err != nil {
msg := err.Error()
if msg != "" {
fmt.Fprintf(os.Stderr, "%s: %v\n", os.Args[0], err)
}
os.Exit(1)
}
return
}
}
fmt.Fprintf(os.Stderr, "%s: unknown subcommand %q\nRun 'gomobile help' for usage.\n", os.Args[0], args[0])
os.Exit(2)
}
func determineGoVersion() error {
gobin, err := exec.LookPath("go")
if err != nil {
return errors.New("go not found")
}
goVersionOut, err = exec.Command(gobin, "version").CombinedOutput()
if err != nil {
return fmt.Errorf("'go version' failed: %v, %s", err, goVersionOut)
}
switch {
case bytes.HasPrefix(goVersionOut, []byte("go version go1.4")),
bytes.HasPrefix(goVersionOut, []byte("go version go1.5")),
bytes.HasPrefix(goVersionOut, []byte("go version go1.6")):
return errors.New("Go 1.7 or newer is required")
}
return nil
}
func help(args []string) {
if len(args) == 0 {
printUsage(os.Stdout)
return // succeeded at helping
}
if len(args) != 1 {
fmt.Fprintf(os.Stderr, "usage: %s help command\n\nToo many arguments given.\n", gomobileName)
os.Exit(2) // failed to help
}
arg := args[0]
for _, cmd := range commands {
if cmd.Name == arg {
cmd.usage()
return // succeeded at helping
}
}
fmt.Fprintf(os.Stderr, "Unknown help topic %#q. Run '%s help'.\n", arg, gomobileName)
os.Exit(2)
}
const documentationHeader = `// 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.
// Code generated by 'gomobile help documentation doc.go'. DO NOT EDIT.
`
func helpDocumentation(path string) {
w := new(bytes.Buffer)
w.WriteString(documentationHeader)
w.WriteString("\n/*\n")
if err := usageTmpl.Execute(w, commands); err != nil {
log.Fatal(err)
}
for _, cmd := range commands {
r, rlen := utf8.DecodeRuneInString(cmd.Short)
w.WriteString("\n\n")
w.WriteRune(unicode.ToUpper(r))
w.WriteString(cmd.Short[rlen:])
w.WriteString("\n\nUsage:\n\n\tgomobile " + cmd.Name)
if cmd.Usage != "" {
w.WriteRune(' ')
w.WriteString(cmd.Usage)
}
w.WriteRune('\n')
w.WriteString(cmd.Long)
}
w.WriteString("*/\npackage main // import \"golang.org/x/mobile/cmd/gomobile\"\n")
if err := ioutil.WriteFile(path, w.Bytes(), 0666); err != nil {
log.Fatal(err)
}
}
var commands = []*command{
// TODO(crawshaw): cmdRun
cmdBind,
cmdBuild,
cmdClean,
cmdInit,
cmdInstall,
cmdVersion,
}
type command struct {
run func(*command) error
flag flag.FlagSet
Name string
Usage string
Short string
Long string
}
func (cmd *command) usage() {
fmt.Fprintf(os.Stdout, "usage: %s %s %s\n%s", gomobileName, cmd.Name, cmd.Usage, cmd.Long)
}
var usageTmpl = template.Must(template.New("usage").Parse(
`Gomobile is a tool for building and running mobile apps written in Go.
To install:
$ go get golang.org/x/mobile/cmd/gomobile
$ gomobile init
At least Go 1.7 is required.
For detailed instructions, see https://golang.org/wiki/Mobile.
Usage:
gomobile command [arguments]
Commands:
{{range .}}
{{.Name | printf "%-11s"}} {{.Short}}{{end}}
Use 'gomobile help [command]' for more information about that command.
`))