1// Copyright 2022 The Go Authors. All rights reserved.2// Use of this source code is governed by a BSD-style3// license that can be found in the LICENSE file.45//go:build ignore67// Mkzip writes a zoneinfo.zip with the content of the current directory8// and its subdirectories, with no compression, suitable for package time.9//10// Usage:11//12//	go run ../../mkzip.go ../../zoneinfo.zip13//14// We use this program instead of 'zip -0 -r ../../zoneinfo.zip *' to get15// a reproducible generator that does not depend on which version of the16// external zip tool is used or the ordering of file names in a directory17// or the current time.18package main1920import (21	"archive/zip"22	"bytes"23	"flag"24	"fmt"25	"hash/crc32"26	"io/fs"27	"log"28	"os"29	"path/filepath"30	"strings"31)3233func usage() {34	fmt.Fprintf(os.Stderr, "usage: go run mkzip.go zoneinfo.zip\n")35	os.Exit(2)36}3738func main() {39	log.SetPrefix("mkzip: ")40	log.SetFlags(0)41	flag.Usage = usage42	flag.Parse()43	args := flag.Args()44	if len(args) != 1 || !strings.HasSuffix(args[0], ".zip") {45		usage()46	}4748	var zb bytes.Buffer49	zw := zip.NewWriter(&zb)50	seen := make(map[string]bool)51	err := filepath.WalkDir(".", func(path string, d fs.DirEntry, err error) error {52		if d.IsDir() {53			return nil54		}55		data, err := os.ReadFile(path)56		if err != nil {57			log.Fatal(err)58		}59		if strings.HasSuffix(path, ".zip") {60			log.Fatalf("unexpected file during walk: %s", path)61		}62		name := filepath.ToSlash(path)63		w, err := zw.CreateRaw(&zip.FileHeader{64			Name:               name,65			Method:             zip.Store,66			CompressedSize64:   uint64(len(data)),67			UncompressedSize64: uint64(len(data)),68			CRC32:              crc32.ChecksumIEEE(data),69		})70		if err != nil {71			log.Fatal(err)72		}73		if _, err := w.Write(data); err != nil {74			log.Fatal(err)75		}76		seen[name] = true77		return nil78	})79	if err != nil {80		log.Fatal(err)81	}82	if err := zw.Close(); err != nil {83		log.Fatal(err)84	}85	if len(seen) == 0 {86		log.Fatalf("did not find any files to add")87	}88	if !seen["US/Eastern"] {89		log.Fatalf("did not find US/Eastern to add")90	}91	if err := os.WriteFile(args[0], zb.Bytes(), 0666); err != nil {92		log.Fatal(err)93	}94}