protocol/bc/types/spend_commitment.go

   1 package types
   2
   3 import (
   4         "fmt"
   5         "io"
   6
   7         "github.com/bytom/bytom/encoding/blockchain"
   8         "github.com/bytom/bytom/errors"
   9         "github.com/bytom/bytom/protocol/bc"
  10 )
  11
  12 // SpendCommitment contains the commitment data for a transaction output.
  13 type SpendCommitment struct {
  14         bc.AssetAmount
  15         SourceID       bc.Hash
  16         SourcePosition uint64
  17         VMVersion      uint64
  18         ControlProgram []byte
  19         StateData      [][]byte
  20 }
  21
  22 func (sc *SpendCommitment) writeExtensibleString(w io.Writer, suffix []byte, assetVersion uint64) error {
  23         _, err := blockchain.WriteExtensibleString(w, suffix, func(w io.Writer) error {
  24                 return sc.writeContents(w, suffix, assetVersion)
  25         })
  26         return err
  27 }
  28
  29 func (sc *SpendCommitment) writeContents(w io.Writer, suffix []byte, assetVersion uint64) (err error) {
  30         if assetVersion == 1 {
  31                 if _, err = sc.SourceID.WriteTo(w); err != nil {
  32                         return errors.Wrap(err, "writing source id")
  33                 }
  34                 if _, err = sc.AssetAmount.WriteTo(w); err != nil {
  35                         return errors.Wrap(err, "writing asset amount")
  36                 }
  37                 if _, err = blockchain.WriteVarint63(w, sc.SourcePosition); err != nil {
  38                         return errors.Wrap(err, "writing source position")
  39                 }
  40                 if _, err = blockchain.WriteVarint63(w, sc.VMVersion); err != nil {
  41                         return errors.Wrap(err, "writing vm version")
  42                 }
  43                 if _, err = blockchain.WriteVarstr31(w, sc.ControlProgram); err != nil {
  44                         return errors.Wrap(err, "writing control program")
  45                 }
  46                 if _, err = blockchain.WriteVarstrList(w, sc.StateData); err != nil {
  47                         return errors.Wrap(err, "writing state data")
  48                 }
  49         }
  50         if len(suffix) > 0 {
  51                 _, err = w.Write(suffix)
  52         }
  53         return errors.Wrap(err, "writing suffix")
  54 }
  55
  56 func (sc *SpendCommitment) readFrom(r *blockchain.Reader, assetVersion uint64) (suffix []byte, err error) {
  57         return blockchain.ReadExtensibleString(r, func(r *blockchain.Reader) error {
  58                 if assetVersion == 1 {
  59                         if _, err := sc.SourceID.ReadFrom(r); err != nil {
  60                                 return errors.Wrap(err, "reading source id")
  61                         }
  62                         if err = sc.AssetAmount.ReadFrom(r); err != nil {
  63                                 return errors.Wrap(err, "reading asset+amount")
  64                         }
  65                         if sc.SourcePosition, err = blockchain.ReadVarint63(r); err != nil {
  66                                 return errors.Wrap(err, "reading source position")
  67                         }
  68                         if sc.VMVersion, err = blockchain.ReadVarint63(r); err != nil {
  69                                 return errors.Wrap(err, "reading VM version")
  70                         }
  71                         if sc.VMVersion != 1 {
  72                                 return fmt.Errorf("unrecognized VM version %d for asset version 1", sc.VMVersion)
  73                         }
  74                         if sc.ControlProgram, err = blockchain.ReadVarstr31(r); err != nil {
  75                                 return errors.Wrap(err, "reading control program")
  76                         }
  77                         if sc.StateData, err = blockchain.ReadVarstrList(r); err != nil {
  78                                 return errors.Wrap(err, "reading state data")
  79                         }
  80                         return nil
  81                 }
  82                 return nil
  83         })
  84 }