blob: 417e860ece009b8711aa3cce37cf094efa668e85 [file] [log] [blame]
// Copyright 2017 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.
// +build !plan9
// The getgo command installs Go to the user's system.
package main
import (
"bufio"
"context"
"errors"
"flag"
"fmt"
exec "golang.org/x/sys/execabs"
"os"
"strings"
)
var (
interactive = flag.Bool("i", false, "Interactive mode, prompt for inputs.")
verbose = flag.Bool("v", false, "Verbose.")
setupOnly = flag.Bool("skip-dl", false, "Don't download - only set up environment variables")
goVersion = flag.String("version", "", `Version of Go to install (e.g. "1.8.3"). If empty, uses the latest version.`)
version = "devel"
)
var errExitCleanly error = errors.New("exit cleanly sentinel value")
func main() {
flag.Parse()
if *goVersion != "" && !strings.HasPrefix(*goVersion, "go") {
*goVersion = "go" + *goVersion
}
ctx := context.Background()
verbosef("version " + version)
runStep := func(s step) {
err := s(ctx)
if err == errExitCleanly {
os.Exit(0)
}
if err != nil {
fmt.Fprintln(os.Stderr, err)
os.Exit(2)
}
}
if !*setupOnly {
runStep(welcome)
runStep(checkOthers)
runStep(chooseVersion)
runStep(downloadGo)
}
runStep(setupGOPATH)
}
func verbosef(format string, v ...interface{}) {
if !*verbose {
return
}
fmt.Printf(format+"\n", v...)
}
func prompt(ctx context.Context, query, defaultAnswer string) (string, error) {
if !*interactive {
return defaultAnswer, nil
}
fmt.Printf("%s [%s]: ", query, defaultAnswer)
type result struct {
answer string
err error
}
ch := make(chan result, 1)
go func() {
s := bufio.NewScanner(os.Stdin)
if !s.Scan() {
ch <- result{"", s.Err()}
return
}
answer := s.Text()
if answer == "" {
answer = defaultAnswer
}
ch <- result{answer, nil}
}()
select {
case r := <-ch:
return r.answer, r.err
case <-ctx.Done():
return "", ctx.Err()
}
}
func runCommand(ctx context.Context, prog string, args ...string) ([]byte, error) {
verbosef("Running command: %s %v", prog, args)
cmd := exec.CommandContext(ctx, prog, args...)
out, err := cmd.CombinedOutput()
if err != nil {
return nil, fmt.Errorf("running cmd '%s %s' failed: %s err: %v", prog, strings.Join(args, " "), string(out), err)
}
if out != nil && err == nil && len(out) != 0 {
verbosef("%s", out)
}
return out, nil
}