blob: 29fb53504da2787e17c4f60256d1c08cf5a3dab7 [file] [log] [blame]
// Copyright 2014 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 ignore
package main
import (
"bytes"
"flag"
"go/format"
"io/ioutil"
"log"
"net/http"
"os"
"os/exec"
"strings"
"text/template"
)
const (
goRepoPath = 1 << iota
packagePath
)
var tmpl = template.Must(template.New("").Parse(`// Created by go generate; DO NOT EDIT
// Copyright 2014 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 gosrc
const (
goRepoPath = {{.goRepoPath}}
packagePath = {{.packagePath}}
)
var pathFlags = map[string]int{
{{range $k, $v := .pathFlags}}{{printf "%q" $k}}: {{$v}},
{{end}} }
var validTLDs = map[string]bool{
{{range $v := .validTLDs}}{{printf "%q" $v}}: true,
{{end}} }
`))
var output = flag.String("output", "data.go", "file name to write")
func main() {
log.SetFlags(0)
log.SetPrefix("gen: ")
flag.Parse()
if flag.NArg() != 0 {
log.Fatal("usage: decgen [--output filename]")
}
// Build map of standard repository path flags.
cmd := exec.Command("go", "list", "std", "cmd")
p, err := cmd.Output()
if err != nil {
log.Fatal(err)
}
pathFlags := map[string]int{
"builtin": packagePath | goRepoPath,
"C": packagePath,
}
for _, path := range strings.Fields(string(p)) {
pathFlags[path] |= packagePath | goRepoPath
for {
i := strings.LastIndex(path, "/")
if i < 0 {
break
}
path = path[:i]
pathFlags[path] |= goRepoPath
}
}
// Get list of valid TLDs.
resp, err := http.Get("https://data.iana.org/TLD/tlds-alpha-by-domain.txt")
if err != nil {
log.Fatal(err)
}
defer resp.Body.Close()
p, err = ioutil.ReadAll(resp.Body)
if err != nil {
log.Fatal(err)
}
var validTLDs []string
for _, line := range strings.Split(string(p), "\n") {
line = strings.TrimSpace(line)
if len(line) == 0 || line[0] == '#' {
continue
}
validTLDs = append(validTLDs, "."+strings.ToLower(line))
}
// Generate output.
var buf bytes.Buffer
err = tmpl.Execute(&buf, map[string]interface{}{
"output": *output,
"goRepoPath": goRepoPath,
"packagePath": packagePath,
"pathFlags": pathFlags,
"validTLDs": validTLDs,
})
if err != nil {
log.Fatal("template error:", err)
}
source, err := format.Source(buf.Bytes())
if err != nil {
log.Fatal("source format error:", err)
}
fd, err := os.Create(*output)
_, err = fd.Write(source)
if err != nil {
log.Fatal(err)
}
}