cmd/torrent-metainfo-pprint/main.go

   1 package main
   2
   3 import (
   4         "bufio"
   5         "encoding/hex"
   6         "encoding/json"
   7         "fmt"
   8         "io"
   9         "log"
  10         "os"
  11
  12         "github.com/anacrolix/envpprof"
  13         "github.com/anacrolix/tagflag"
  14         "github.com/anacrolix/torrent/metainfo"
  15         "github.com/bradfitz/iter"
  16 )
  17
  18 var flags struct {
  19         JustName    bool
  20         PieceHashes bool
  21         Files       bool
  22         tagflag.StartPos
  23 }
  24
  25 func processReader(r io.Reader) error {
  26         metainfo, err := metainfo.Load(r)
  27         if err != nil {
  28                 return err
  29         }
  30         info, err := metainfo.UnmarshalInfo()
  31         if err != nil {
  32                 return fmt.Errorf("error unmarshalling info: %s", err)
  33         }
  34         if flags.JustName {
  35                 fmt.Printf("%s\n", info.Name)
  36                 return nil
  37         }
  38         d := map[string]interface{}{
  39                 "Name":         info.Name,
  40                 "NumPieces":    info.NumPieces(),
  41                 "PieceLength":  info.PieceLength,
  42                 "InfoHash":     metainfo.HashInfoBytes().HexString(),
  43                 "NumFiles":     len(info.UpvertedFiles()),
  44                 "TotalLength":  info.TotalLength(),
  45                 "Announce":     metainfo.Announce,
  46                 "AnnounceList": metainfo.AnnounceList,
  47                 "UrlList":      metainfo.UrlList,
  48         }
  49         if flags.Files {
  50                 d["Files"] = info.Files
  51         }
  52         if flags.PieceHashes {
  53                 d["PieceHashes"] = func() (ret []string) {
  54                         for i := range iter.N(info.NumPieces()) {
  55                                 ret = append(ret, hex.EncodeToString(info.Pieces[i*20:(i+1)*20]))
  56                         }
  57                         return
  58                 }()
  59         }
  60         b, _ := json.MarshalIndent(d, "", "  ")
  61         _, err = os.Stdout.Write(b)
  62         return err
  63 }
  64
  65 func main() {
  66         defer envpprof.Stop()
  67         tagflag.Parse(&flags)
  68         err := processReader(bufio.NewReader(os.Stdin))
  69         if err != nil {
  70                 log.Fatal(err)
  71         }
  72         if !flags.JustName {
  73                 os.Stdout.WriteString("\n")
  74         }
  75 }