// fetchHeaderBlocks creates and sends a request to the syncPeer for the next
// list of blocks to be downloaded based on the current list of headers.
func (b *blockManager) fetchHeaderBlocks() {
// Nothing to do if there is no start header.
if b.startHeader == nil {
bmgrLog.Warnf("fetchHeaderBlocks called with no start header")
return
}
// Build up a getdata request for the list of blocks the headers
// describe. The size hint will be limited to btcwire.MaxInvPerMsg by
// the function, so no need to double check it here.
gdmsg := btcwire.NewMsgGetDataSizeHint(uint(b.headerList.Len()))
numRequested := 0
for e := b.startHeader; e != nil; e = e.Next() {
node, ok := e.Value.(*headerNode)
if !ok {
bmgrLog.Warn("Header list node type is not a headerNode")
continue
}
iv := btcwire.NewInvVect(btcwire.InvTypeBlock, node.sha)
if !b.haveInventory(iv) {
b.requestedBlocks[*node.sha] = true
b.syncPeer.requestedBlocks[*node.sha] = true
gdmsg.AddInvVect(iv)
numRequested++
}
b.startHeader = e.Next()
if numRequested >= btcwire.MaxInvPerMsg {
break
}
}
if len(gdmsg.InvList) > 0 {
b.syncPeer.QueueMessage(gdmsg, nil)
}
}
// TestGetData tests the MsgGetData API.
func TestGetData(t *testing.T) {
pver := btcwire.ProtocolVersion
// Ensure the command is expected value.
wantCmd := "getdata"
msg := btcwire.NewMsgGetData()
if cmd := msg.Command(); cmd != wantCmd {
t.Errorf("NewMsgGetData: wrong command - got %v want %v",
cmd, wantCmd)
}
// Ensure max payload is expected value for latest protocol version.
// Num inventory vectors (varInt) + max allowed inventory vectors.
wantPayload := uint32(1800009)
maxPayload := msg.MaxPayloadLength(pver)
if maxPayload != wantPayload {
t.Errorf("MaxPayloadLength: wrong max payload length for "+
"protocol version %d - got %v, want %v", pver,
maxPayload, wantPayload)
}
// Ensure inventory vectors are added properly.
hash := btcwire.ShaHash{}
iv := btcwire.NewInvVect(btcwire.InvTypeBlock, &hash)
err := msg.AddInvVect(iv)
if err != nil {
t.Errorf("AddInvVect: %v", err)
}
if msg.InvList[0] != iv {
t.Errorf("AddInvVect: wrong invvect added - got %v, want %v",
spew.Sprint(msg.InvList[0]), spew.Sprint(iv))
}
// Ensure adding more than the max allowed inventory vectors per
// message returns an error.
for i := 0; i < btcwire.MaxInvPerMsg; i++ {
err = msg.AddInvVect(iv)
}
if err == nil {
t.Errorf("AddInvVect: expected error on too many inventory " +
"vectors not received")
}
// Ensure creating the message with a size hint larger than the max
// works as expected.
msg = btcwire.NewMsgGetDataSizeHint(btcwire.MaxInvPerMsg + 1)
wantCap := btcwire.MaxInvPerMsg
if cap(msg.InvList) != wantCap {
t.Errorf("NewMsgGetDataSizeHint: wrong cap for size hint - "+
"got %v, want %v", cap(msg.InvList), wantCap)
}
return
}
// fetchHeaderBlocks is creates and sends a request to the syncPeer for
// the next list of blocks to downloaded.
func (b *blockManager) fetchHeaderBlocks() {
gdmsg := btcwire.NewMsgGetDataSizeHint(btcwire.MaxInvPerMsg)
numRequested := 0
startBlock := b.startBlock
for {
if b.startBlock == nil {
break
}
blockhash := b.startBlock
firstblock, ok := b.headerPool[*blockhash]
if !ok {
bmgrLog.Warnf("current fetch block %v missing from headerPool", blockhash)
break
}
var iv btcwire.InvVect
iv.Hash = *blockhash
iv.Type = btcwire.InvTypeBlock
if !b.haveInventory(&iv) {
b.requestedBlocks[*blockhash] = true
b.syncPeer.requestedBlocks[*blockhash] = true
gdmsg.AddInvVect(&iv)
numRequested++
}
if b.fetchBlock == nil {
b.fetchBlock = b.startBlock
}
if firstblock.next == nil {
b.startBlock = nil
break
} else {
b.startBlock = &firstblock.next.sha
}
if numRequested >= btcwire.MaxInvPerMsg {
break
}
}
if len(gdmsg.InvList) > 0 {
bmgrLog.Debugf("requesting block %v len %v\n", startBlock, len(gdmsg.InvList))
b.syncPeer.QueueMessage(gdmsg, nil)
}
}