// Prepare configures the result cache to allow accepting and caching inbound
// fetch results.
func (q *queue) Prepare(offset uint64, mode SyncMode, pivot uint64, head *types.Header) {
q.lock.Lock()
defer q.lock.Unlock()
// Prepare the queue for sync results
if q.resultOffset < offset {
q.resultOffset = offset
}
q.fastSyncPivot = pivot
q.mode = mode
// If long running fast sync, also start up a head stateretrieval immediately
if mode == FastSync && pivot > 0 {
q.stateScheduler = state.NewStateSync(head.Root, q.stateDatabase)
}
}
// Schedule adds a set of headers for the download queue for scheduling, returning
// the new headers encountered.
func (q *queue) Schedule(headers []*types.Header, from uint64) []*types.Header {
q.lock.Lock()
defer q.lock.Unlock()
// Insert all the headers prioritised by the contained block number
inserts := make([]*types.Header, 0, len(headers))
for _, header := range headers {
// Make sure chain order is honoured and preserved throughout
hash := header.Hash()
if header.Number == nil || header.Number.Uint64() != from {
glog.V(logger.Warn).Infof("Header #%v [%x] broke chain ordering, expected %d", header.Number, hash[:4], from)
break
}
if q.headerHead != (common.Hash{}) && q.headerHead != header.ParentHash {
glog.V(logger.Warn).Infof("Header #%v [%x] broke chain ancestry", header.Number, hash[:4])
break
}
// Make sure no duplicate requests are executed
if _, ok := q.blockTaskPool[hash]; ok {
glog.V(logger.Warn).Infof("Header #%d [%x] already scheduled for block fetch", header.Number.Uint64(), hash[:4])
continue
}
if _, ok := q.receiptTaskPool[hash]; ok {
glog.V(logger.Warn).Infof("Header #%d [%x] already scheduled for receipt fetch", header.Number.Uint64(), hash[:4])
continue
}
// Queue the header for content retrieval
q.blockTaskPool[hash] = header
q.blockTaskQueue.Push(header, -float32(header.Number.Uint64()))
if q.mode == FastSync && header.Number.Uint64() <= q.fastSyncPivot {
// Fast phase of the fast sync, retrieve receipts too
q.receiptTaskPool[hash] = header
q.receiptTaskQueue.Push(header, -float32(header.Number.Uint64()))
}
if q.mode == FastSync && header.Number.Uint64() == q.fastSyncPivot {
// Pivoting point of the fast sync, retrieve the state tries
q.stateSchedLock.Lock()
q.stateScheduler = state.NewStateSync(header.Root, q.stateDatabase)
q.stateSchedLock.Unlock()
}
inserts = append(inserts, header)
q.headerHead = hash
from++
}
return inserts
}