Make -reindex cope with out-of-order blocks

Remember out-of-order block headers along with disk positions. This is
likely the simplest and least-impact way to make -reindex work with
headers first.

Based on top of #4468.
This commit is contained in:
Wladimir J. van der Laan 2014-10-07 18:06:30 +02:00 committed by Pieter Wuille
parent e17bd58392
commit ad96e7ccd9

View File

@ -3070,6 +3070,8 @@ void PrintBlockTree()
bool LoadExternalBlockFile(FILE* fileIn, CDiskBlockPos *dbp)
{
// Map of disk positions for blocks with unknown parent (only used for reindex)
static std::multimap<uint256, CDiskBlockPos> mapBlocksUnknownParent;
int64_t nStart = GetTimeMillis();
int nLoaded = 0;
@ -3112,20 +3114,64 @@ bool LoadExternalBlockFile(FILE* fileIn, CDiskBlockPos *dbp)
try {
// read block
uint64_t nBlockPos = blkdat.GetPos();
if (nBlockPos < nStartByte) // skip already indexed part
continue;
if (dbp)
dbp->nPos = nBlockPos;
blkdat.SetLimit(nBlockPos + nSize);
// read block header
CBlockHeader blockhdr;
blkdat >> blockhdr;
nRewind = blkdat.GetPos();
// process block header
uint256 hash = blockhdr.GetHash();
if (hash != Params().HashGenesisBlock() && mapBlockIndex.find(blockhdr.hashPrevBlock) == mapBlockIndex.end()) {
LogPrint("reindex", "%s: Out of order block %s, parent %s not known\n", __func__, hash.ToString(),
blockhdr.hashPrevBlock.ToString());
if (dbp)
mapBlocksUnknownParent.insert(std::make_pair(blockhdr.hashPrevBlock, *dbp));
// TODO a slight optimization would be: blkdat.Skip(nSize - 80)
continue;
}
// read block
blkdat.SetPos(nBlockPos);
CBlock block;
blkdat >> block;
nRewind = blkdat.GetPos();
// process block
if (nBlockPos >= nStartByte) {
if (dbp)
dbp->nPos = nBlockPos;
CValidationState state;
if (ProcessBlock(state, NULL, &block, dbp))
nLoaded++;
if (state.IsError())
break;
CValidationState state;
if (ProcessBlock(state, NULL, &block, dbp))
nLoaded++;
if (state.IsError())
break;
// Recursively process earlier encountered successors of this block
deque<uint256> queue;
queue.push_back(hash);
while (!queue.empty()) {
uint256 head = queue.front();
queue.pop_front();
std::pair<std::multimap<uint256, CDiskBlockPos>::iterator, std::multimap<uint256, CDiskBlockPos>::iterator> range = mapBlocksUnknownParent.equal_range(head);
while (range.first != range.second) {
std::multimap<uint256, CDiskBlockPos>::iterator it = range.first;
if (ReadBlockFromDisk(block, it->second))
{
LogPrintf("%s: Processing out of order child %s of %s\n", __func__, block.GetHash().ToString(),
head.ToString());
CValidationState dummy;
if (ProcessBlock(dummy, NULL, &block, &it->second))
{
nLoaded++;
queue.push_back(block.GetHash());
}
}
range.first++;
mapBlocksUnknownParent.erase(it);
}
}
} catch (std::exception &e) {
LogPrintf("%s : Deserialize or I/O error - %s", __func__, e.what());