nursery_store: tightens up height index pruning and formatting
This commit is contained in:
Conner Fromknecht
parent
23e36a58f0
commit
ef81f0064c
387
nursery_store.go
387
nursery_store.go
@ -3,6 +3,7 @@ package main
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import (
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"bytes"
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"errors"
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"fmt"
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"github.com/boltdb/bolt"
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"github.com/lightningnetwork/lnd/channeldb"
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@ -38,7 +39,6 @@ type NurseryStore interface {
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// channel indexes. If this method detects that all outputs for a
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// particular contract have been incubated, it returns the channel
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// points that are ready to be marked as fully closed.
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// TODO: make this handle one output at a time?
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GraduateKinder([]kidOutput) error
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// FinalizeHeight accepts a block height as a parameter and purges its
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@ -310,32 +310,10 @@ func (ns *nurseryStore) CribToKinder(bby *babyOutput) error {
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return err
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}
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// Next, retrieve the height-channel bucket located in the
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// height bucket corresponding to the baby output's CLTV expiry
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// height. This bucket should always exist, but if it doesn't
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// then we have nothing to clean up.
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hghtChanBucketCltv := ns.getHeightChanBucket(tx, bby.expiry,
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chanPoint)
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if hghtChanBucketCltv != nil {
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// We successfully located an existing height chan
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// bucket at this babyOutput's expiry height, proceed by
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// removing it from the index.
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err := hghtChanBucketCltv.Delete(pfxOutputKey)
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if err != nil {
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return err
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}
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// Since we removed a crib output from the height index,
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// we opportunistically prune the height bucket
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// corresponding to the babyOutput's CLTV delay. This
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// allows us to clean up any persistent state as outputs
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// are progressed through the incubation process.
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pruned, err := ns.pruneHeight(tx, bby.expiry)
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if err != nil && err != ErrBucketNotEmpty {
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return err
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} else if err == nil && pruned {
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utxnLog.Infof("Height bucket %d pruned", bby.expiry)
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}
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err = ns.removeOutputFromHeight(tx, bby.expiry, chanPoint,
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pfxOutputKey)
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if err != nil {
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return err
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}
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// Since we are moving this output from the crib bucket to the
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@ -447,68 +425,46 @@ func (ns *nurseryStore) PreschoolToKinder(kid *kidOutput) error {
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return err
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}
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// Finally, we touch a bucket in the height-channel created
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// above. The bucket is named using a kindergarten prefixed
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// key, signaling that this CSV delayed output will be ready to
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// broadcast at the maturity height, after a brief period of
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// incubation.
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_, err = hghtChanBucket.CreateBucketIfNotExists(pfxOutputKey)
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return err
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// Finally, we touch a key in the height-channel created above.
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// The key is named using a kindergarten prefixed key, signaling
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// that this CSV delayed output will be ready to broadcast at
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// the maturity height, after a brief period of incubation.
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return hghtChanBucket.Put(pfxOutputKey, []byte{})
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})
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}
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// GraduateKinder accepts a list of kidOutputs in the kindergarten bucket,
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// removing their corresponding entries from the height and channel indexes.
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// If this method detects that all outputs for a particular contract have been
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// incubated, it returns the channel points that are ready to be marked as
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// fully closed. This method will iterate through the provided kidOutputs and do
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// the following:
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// 1) Prune the kid height bucket at the kid's confirmation height, if it is
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// empty.
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// 2) Prune the channel bucket belonging to the kid's origin channel point, if
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// it is empty.
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// GraduateKinder accepts a list of kidOutputs in the kindergarten bucket and
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// marks them as graduated. This method also removes their corresponding entries
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// from the height and channel indexes corresponding to their kindergarten
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// status.
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func (ns *nurseryStore) GraduateKinder(kids []kidOutput) error {
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if err := ns.db.Update(func(tx *bolt.Tx) error {
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for _, kid := range kids {
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confHeight := kid.ConfHeight()
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outpoint := kid.OutPoint()
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chanPoint := kid.OriginChanPoint()
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// Construct the key under which the output is currently
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// stored height and channel indexes.
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pfxOutputKey, err := prefixOutputKey(kndrPrefix, outpoint)
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pfxOutputKey, err := prefixOutputKey(kndrPrefix,
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outpoint)
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if err != nil {
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return err
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}
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// Load the height-channel bucket, remove this output,
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// and attempt to prune the bucket if it empty.
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hghtChanBucket := ns.getHeightChanBucket(tx, confHeight, chanPoint)
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if hghtChanBucket != nil {
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if err := hghtChanBucket.Delete(pfxOutputKey); err != nil {
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return err
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}
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// Attempt to prune the height bucket matching the kid
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// output's confirmation height if it contains no active
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// outputs.
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pruned, err := ns.pruneHeight(tx, confHeight)
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if err != nil && err != ErrBucketNotEmpty {
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return err
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} else if err == nil && pruned {
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utxnLog.Infof("Height bucket %d pruned", confHeight)
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}
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}
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chanBucket, err := ns.createChannelBucket(tx, chanPoint)
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// Remove the grad output's entry in the height index.
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err = ns.removeOutputFromHeight(tx, confHeight, chanPoint,
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pfxOutputKey)
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if err != nil {
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return err
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}
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chanBucket := ns.getChannelBucket(tx, chanPoint)
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if chanBucket == nil {
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return ErrContractNotFound
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}
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// Remove previous output with kindergarten prefix.
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if err := chanBucket.Delete(pfxOutputKey); err != nil {
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return err
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@ -528,7 +484,6 @@ func (ns *nurseryStore) GraduateKinder(kids []kidOutput) error {
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if err != nil {
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return err
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}
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}
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return nil
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@ -555,52 +510,54 @@ func (ns *nurseryStore) FinalizeHeight(height uint32) error {
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// FetchClass returns a list of babyOutputs in the crib bucket whose CLTV
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// delay expires at the provided block height.
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func (ns *nurseryStore) FetchClass(height uint32) ([]kidOutput, []babyOutput, error) {
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func (ns *nurseryStore) FetchClass(
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height uint32) ([]kidOutput, []babyOutput, error) {
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// Construct list of all crib and kindergarten outputs that need TLC at
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// the provided block height.
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var kids []kidOutput
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var babies []babyOutput
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if err := ns.db.View(func(tx *bolt.Tx) error {
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if err := ns.forEachHeightPrefix(tx, cribPrefix, height, func(buf []byte) error {
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// Append each crib output to our list of babyOutputs.
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if err := ns.forEachHeightPrefix(tx, cribPrefix, height,
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func(buf []byte) error {
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// We will attempt to deserialize all outputs
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// stored with the crib prefix into babyOutputs,
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// since this is the expected type that would
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// have been serialized previously.
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var baby babyOutput
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babyReader := bytes.NewReader(buf)
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if err := baby.Decode(babyReader); err != nil {
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return err
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}
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// We will attempt to deserialize all outputs
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// stored with the crib prefix into babyOutputs,
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// since this is the expected type that would
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// have been serialized previously.
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var baby babyOutput
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babyReader := bytes.NewReader(buf)
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if err := baby.Decode(babyReader); err != nil {
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return err
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}
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// Append the deserialized object to our list of
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// babyOutputs.
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babies = append(babies, baby)
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babies = append(babies, baby)
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return nil
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return nil
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}); err != nil {
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}); err != nil {
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return err
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}
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return ns.forEachHeightPrefix(tx, kndrPrefix, height, func(buf []byte) error {
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// We will attempt to deserialize all outputs stored
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// with the kindergarten prefix into kidOutputs, since
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// this is the expected type that would have been
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// serialized previously.
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var kid kidOutput
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kidReader := bytes.NewReader(buf)
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if err := kid.Decode(kidReader); err != nil {
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return err
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}
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// Append each kindergarten output to our list of kidOutputs.
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return ns.forEachHeightPrefix(tx, kndrPrefix, height,
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func(buf []byte) error {
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// We will attempt to deserialize all outputs
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// stored with the kindergarten prefix into
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// kidOutputs, since this is the expected type
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// that would have been serialized previously.
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var kid kidOutput
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kidReader := bytes.NewReader(buf)
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if err := kid.Decode(kidReader); err != nil {
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return err
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}
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// Append the deserialized object to our list of
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// kidOutputs.
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kids = append(kids, kid)
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kids = append(kids, kid)
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return nil
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return nil
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})
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})
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}); err != nil {
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return nil, nil, err
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@ -675,8 +632,6 @@ func (ns *nurseryStore) FetchPreschools() ([]kidOutput, error) {
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// preschool outputs.
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kids = append(kids, psclOutput)
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// Advance to the subsequent key-value pair of
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// the prefix scan.
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pfxOutputKey, kidBytes = c.Next()
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}
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}
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@ -711,28 +666,31 @@ var errImmatureChannel = errors.New("channel has non-graduated outputs")
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// IsMatureChannel determines the whether or not all of the outputs in a
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// particular channel bucket have been marked as graduated.
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func (ns *nurseryStore) IsMatureChannel(chanPoint *wire.OutPoint) (bool, error) {
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if err := ns.db.View(func(tx *bolt.Tx) error {
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err := ns.db.View(func(tx *bolt.Tx) error {
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// Iterate over the contents of the channel bucket, computing
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// both total number of outputs, and those that have the grad
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// prefix.
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return ns.forChanOutputs(tx, chanPoint, func(pfxKey, _ []byte) error {
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if string(pfxKey[:4]) != string(gradPrefix) {
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utxnLog.Infof("Found non-graduated output: %x", pfxKey)
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return errImmatureChannel
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}
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return nil
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})
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return ns.forChanOutputs(tx, chanPoint,
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func(pfxKey, _ []byte) error {
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if string(pfxKey[:4]) != string(gradPrefix) {
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utxnLog.Infof("Found non-graduated "+
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"output: %x", pfxKey)
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return errImmatureChannel
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}
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return nil
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})
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}); err != nil && err != errImmatureChannel {
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})
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if err != nil && err != errImmatureChannel {
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return false, err
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} else {
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return err == nil, nil
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}
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return err == nil, nil
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}
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// RemoveChannel channel erases all entries from the channel bucket for the
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// provided channel point.
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// NOTE: The channel's entries in the height index are assumed to be removed.
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func (ns *nurseryStore) RemoveChannel(chanPoint *wire.OutPoint) error {
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return ns.db.Update(func(tx *bolt.Tx) error {
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// Retrieve the existing chain bucket for this nursery store.
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@ -753,13 +711,42 @@ func (ns *nurseryStore) RemoveChannel(chanPoint *wire.OutPoint) error {
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if err := writeOutpoint(&chanBuffer, chanPoint); err != nil {
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return err
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}
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chanBytes := chanBuffer.Bytes()
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err := chanIndex.DeleteBucket(chanBuffer.Bytes())
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utxnLog.Infof("Pruning and removing channel: %v", chanPoint)
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err := ns.forChanOutputs(tx, chanPoint, func(k, v []byte) error {
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if string(k[:4]) != string(gradPrefix) {
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return errors.New("expected grad output")
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}
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// Construct a kindergarten prefixed key, since this
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// would have been the preceding state for a grad
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// output.
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kndrKey := make([]byte, len(k))
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copy(kndrKey, k)
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copy(kndrKey[:4], kndrPrefix)
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// Decode each to retrieve the output's maturity height.
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var kid kidOutput
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if err := kid.Decode(bytes.NewReader(v)); err != nil {
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return err
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}
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maturityHeight := kid.ConfHeight() + kid.BlocksToMaturity()
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hghtBucket := ns.getHeightBucket(tx, maturityHeight)
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if hghtBucket == nil {
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return nil
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}
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return removeBucketIfExists(hghtBucket, chanBytes)
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})
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if err != nil {
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return err
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}
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return nil
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return removeBucketIfExists(chanIndex, chanBytes)
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})
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}
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@ -942,9 +929,9 @@ func (ns *nurseryStore) createHeightBucket(tx *bolt.Tx,
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return hghtIndex.CreateBucketIfNotExists(heightBytes[:])
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}
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// getHeightBucketPath retrieves an existing height bucket from the nursery store,
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// using the provided block height. If the bucket does not exist, or any bucket
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// along its path does not exist, a nil value is returned.
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// getHeightBucketPath retrieves an existing height bucket from the nursery
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// store, using the provided block height. If the bucket does not exist, or any
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// bucket along its path does not exist, a nil value is returned.
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func (ns *nurseryStore) getHeightBucketPath(tx *bolt.Tx,
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height uint32) (*bolt.Bucket, *bolt.Bucket, *bolt.Bucket) {
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@ -981,18 +968,13 @@ func (ns *nurseryStore) getHeightBucket(tx *bolt.Tx,
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// deleteHeightBucket ensures that the height bucket at the provided index is
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// purged from the nursery store.
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func (ns *nurseryStore) deleteHeightBucket(tx *bolt.Tx, height uint32) error {
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// Ensure that the chain bucket for this nursery store exists.
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chainBucket := tx.Bucket(ns.pfxChainKey)
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if chainBucket == nil {
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// Ensure that the height bucket already exists.
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_, hghtIndex, hghtBucket := ns.getHeightBucketPath(tx, height)
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if hghtBucket == nil {
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return nil
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}
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// Ensure that the height index has been properly initialized for this
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// chain.
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hghtIndex := chainBucket.Bucket(heightIndexKey)
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if hghtIndex == nil {
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return nil
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}
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utxnLog.Infof("Deleting height bucket %d", height)
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// Serialize the provided height, as this will form the name of the
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// bucket.
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@ -1000,12 +982,7 @@ func (ns *nurseryStore) deleteHeightBucket(tx *bolt.Tx, height uint32) error {
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byteOrder.PutUint32(heightBytes[:], height)
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// Finally, delete the bucket in question.
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err := hghtIndex.DeleteBucket(heightBytes[:])
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if err != nil && err != bolt.ErrBucketNotFound {
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return err
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}
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return nil
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return removeBucketIfExists(hghtIndex, heightBytes[:])
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}
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// createHeightChanBucket creates or retrieves an existing height-channel bucket
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@ -1105,7 +1082,8 @@ func (ns *nurseryStore) forEachHeightPrefix(tx *bolt.Tx, prefix []byte,
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// holds a sub-bucket for all outputs maturing at this height.
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hghtChanBucket := hghtBucket.Bucket(chanBytes)
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if hghtChanBucket == nil {
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return errors.New("unable to retrieve height-channel bucket")
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return fmt.Errorf("unable to retrieve height-channel "+
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"bucket at height %d for %x", height, chanBytes)
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}
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// Load the appropriate channel bucket from the channel index,
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@ -1113,7 +1091,7 @@ func (ns *nurseryStore) forEachHeightPrefix(tx *bolt.Tx, prefix []byte,
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// outputs.
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chanBucket := chanIndex.Bucket(chanBytes)
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if chanBucket == nil {
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return errors.New("unable to retrieve channel bucket")
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return fmt.Errorf("unable to retrieve channel bucket: '%x'", chanBytes)
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}
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// Since all of the outputs of interest will start with the same
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@ -1199,8 +1177,6 @@ func (ns *nurseryStore) putLastFinalizedHeight(tx *bolt.Tx,
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return err
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}
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// TODO(conner): purge all state below reorg depth.
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// Serialize the provided last-finalized height, and store it in the
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// top-level chain bucket for this nursery store.
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var lastHeightBytes [4]byte
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@ -1219,6 +1195,60 @@ var (
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ErrBucketNotEmpty = errors.New("bucket is not empty, cannot be pruned")
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)
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// removeOutputFromHeight will delete the given output from the specified
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// height-channel bucket, and attempt to prune the upstream directories if they
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// are empty.
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func (ns *nurseryStore) removeOutputFromHeight(tx *bolt.Tx, height uint32,
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chanPoint *wire.OutPoint, pfxKey []byte) error {
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// Retrieve the height-channel bucket and delete the prefixed output.
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hghtChanBucket := ns.getHeightChanBucket(tx, height, chanPoint)
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if hghtChanBucket == nil {
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// Height-channel bucket already removed.
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return nil
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}
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// Try to delete the prefixed output key if it still exists. The output
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// may have already been removed after confirmation, but a final pass is
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// done when removing a channel as well.
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if hghtChanBucket.Get(pfxKey) != nil {
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if err := hghtChanBucket.Delete(pfxKey); err != nil {
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return err
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}
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}
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// Retrieve the height bucket that contains the height-channel bucket.
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hghtBucket := ns.getHeightBucket(tx, height)
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if hghtBucket == nil {
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return errors.New("height bucket not found")
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}
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var chanBuffer bytes.Buffer
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if err := writeOutpoint(&chanBuffer, chanPoint); err != nil {
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return err
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}
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// Try to remove the channel-height bucket if it this was the last
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// output in the bucket.
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err := removeBucketIfEmpty(hghtBucket, chanBuffer.Bytes())
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if err != nil && err != ErrBucketNotEmpty {
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return err
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} else if err == ErrBucketNotEmpty {
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return nil
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}
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// Attempt to prune the height bucket matching the kid output's
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// confirmation height in case that was the last height-chan bucket.
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pruned, err := ns.pruneHeight(tx, height)
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if err != nil && err != ErrBucketNotEmpty {
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return err
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} else if err == nil && pruned {
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||||
utxnLog.Infof("Height bucket %d pruned", height)
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
// pruneHeight removes the height bucket at the provided height if and only if
|
||||
// all active outputs at this height have been removed from their respective
|
||||
// height-channel buckets.
|
||||
@ -1228,35 +1258,26 @@ func (ns *nurseryStore) pruneHeight(tx *bolt.Tx, height uint32) (bool, error) {
|
||||
if hghtBucket == nil {
|
||||
return false, nil
|
||||
}
|
||||
utxnLog.Infof("pruning height %d", height)
|
||||
|
||||
// TODO(conner): fix this comment
|
||||
// this block height. We will attempt to remove each one if they are
|
||||
// empty, keeping track of the number of height-channel buckets that
|
||||
// still have active outputs.
|
||||
var nActiveBuckets int
|
||||
// Iterate over all channels stored at this block height. We will
|
||||
// attempt to remove each one if they are empty, keeping track of the
|
||||
// number of height-channel buckets that still have active outputs.
|
||||
if err := hghtBucket.ForEach(func(chanBytes, _ []byte) error {
|
||||
// Attempt to each height-channel bucket from the height bucket
|
||||
// located above.
|
||||
_, err := ns.removeBucketIfEmpty(hghtBucket, chanBytes)
|
||||
if err != nil && err != ErrBucketNotEmpty {
|
||||
return err
|
||||
} else if err == ErrBucketNotEmpty {
|
||||
nActiveBuckets++
|
||||
|
||||
hghtChanBucket := hghtBucket.Bucket(chanBytes)
|
||||
if hghtChanBucket == nil {
|
||||
return errors.New("unable to find height-channel bucket")
|
||||
}
|
||||
|
||||
return nil
|
||||
return isBucketEmpty(hghtChanBucket)
|
||||
|
||||
}); err != nil {
|
||||
return false, err
|
||||
}
|
||||
|
||||
// If we located any height-channel buckets that still have active
|
||||
// outputs, it is unsafe to delete this height bucket. Signal this event
|
||||
// to the caller so that they can determine the appropriate action.
|
||||
if nActiveBuckets > 0 {
|
||||
return false, ErrBucketNotEmpty
|
||||
}
|
||||
|
||||
// Serialize the provided block height, such that it can be used as the
|
||||
// key to delete desired height bucket.
|
||||
var heightBytes [4]byte
|
||||
@ -1265,7 +1286,7 @@ func (ns *nurseryStore) pruneHeight(tx *bolt.Tx, height uint32) (bool, error) {
|
||||
// All of the height-channel buckets are empty or have been previously
|
||||
// removed, proceed by removing the height bucket
|
||||
// altogether.
|
||||
if err := hghtIndex.DeleteBucket(heightBytes[:]); err != nil {
|
||||
if err := removeBucketIfExists(hghtIndex, heightBytes[:]); err != nil {
|
||||
return false, err
|
||||
}
|
||||
|
||||
@ -1274,49 +1295,41 @@ func (ns *nurseryStore) pruneHeight(tx *bolt.Tx, height uint32) (bool, error) {
|
||||
|
||||
// removeBucketIfEmpty attempts to delete a bucket specified by name from the
|
||||
// provided parent bucket.
|
||||
func (ns *nurseryStore) removeBucketIfEmpty(parent *bolt.Bucket,
|
||||
bktName []byte) (bool, error) {
|
||||
|
||||
func removeBucketIfEmpty(parent *bolt.Bucket, bktName []byte) error {
|
||||
// Attempt to fetch the named bucket from its parent.
|
||||
bkt := parent.Bucket(bktName)
|
||||
if bkt == nil {
|
||||
// No bucket was found, signal this to the caller.
|
||||
return false, nil
|
||||
// No bucket was found, already removed?
|
||||
return nil
|
||||
}
|
||||
|
||||
// The bucket exists, now compute how many children *it* has.
|
||||
nChildren, err := ns.numChildrenInBucket(bkt)
|
||||
if err != nil {
|
||||
return false, nil
|
||||
// The bucket exists, fail if it still has children.
|
||||
if err := isBucketEmpty(bkt); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
// If the number of children is non-zero, alert the caller that the
|
||||
// named bucket is not being removed.
|
||||
if nChildren > 0 {
|
||||
return false, nil
|
||||
}
|
||||
|
||||
// Otherwise, remove the empty bucket from its parent.
|
||||
err = parent.DeleteBucket(bktName)
|
||||
if err != nil {
|
||||
return false, err
|
||||
}
|
||||
|
||||
return true, nil
|
||||
return parent.DeleteBucket(bktName)
|
||||
}
|
||||
|
||||
// numChildrenInBucket computes the number of children contained in the given
|
||||
// boltdb bucket.
|
||||
func (ns *nurseryStore) numChildrenInBucket(parent *bolt.Bucket) (int, error) {
|
||||
var nChildren int
|
||||
if err := parent.ForEach(func(_, _ []byte) error {
|
||||
nChildren++
|
||||
// removeBucketIfExists safely deletes the named bucket by first checking
|
||||
// that it exists in the parent bucket.
|
||||
func removeBucketIfExists(parent *bolt.Bucket, bktName []byte) error {
|
||||
// Attempt to fetch the named bucket from its parent.
|
||||
bkt := parent.Bucket(bktName)
|
||||
if bkt == nil {
|
||||
// No bucket was found, already removed?
|
||||
return nil
|
||||
}); err != nil {
|
||||
return 0, err
|
||||
}
|
||||
|
||||
return nChildren, nil
|
||||
return parent.DeleteBucket(bktName)
|
||||
}
|
||||
|
||||
// isBucketEmpty returns ErrBucketNotEmpty if the bucket has a non-zero number
|
||||
// of children.
|
||||
func isBucketEmpty(parent *bolt.Bucket) error {
|
||||
return parent.ForEach(func(_, _ []byte) error {
|
||||
return ErrBucketNotEmpty
|
||||
})
|
||||
}
|
||||
|
||||
// Compile-time constraint to ensure nurseryStore implements NurseryStore.
|
||||
|
||||
Loading…
Reference in New Issue
Block a user