LogPrintf("%s: Warning: Large valid fork found\n forking the chain at height %d (%s)\n lasting to height %d (%s).\nChain state database corruption likely.\n", __func__,
assert(rangeGenesis.first == rangeGenesis.second); // There is only one index entry with parent NULL.
// Iterate over the entire block tree, using depth-first search.
// Along the way, remember whether there are blocks on the path from genesis
// block being explored which are the first to have certain properties.
size_t nNodes = 0;
int nHeight = 0;
CBlockIndex* pindexFirstInvalid = NULL; // Oldest ancestor of pindex which is invalid.
CBlockIndex* pindexFirstMissing = NULL; // Oldest ancestor of pindex which does not have BLOCK_HAVE_DATA.
CBlockIndex* pindexFirstNeverProcessed = NULL; // Oldest ancestor of pindex for which nTx == 0.
CBlockIndex* pindexFirstNotTreeValid = NULL; // Oldest ancestor of pindex which does not have BLOCK_VALID_TREE (regardless of being valid or not).
CBlockIndex* pindexFirstNotTransactionsValid = NULL; // Oldest ancestor of pindex which does not have BLOCK_VALID_TRANSACTIONS (regardless of being valid or not).
CBlockIndex* pindexFirstNotChainValid = NULL; // Oldest ancestor of pindex which does not have BLOCK_VALID_CHAIN (regardless of being valid or not).
CBlockIndex* pindexFirstNotScriptsValid = NULL; // Oldest ancestor of pindex which does not have BLOCK_VALID_SCRIPTS (regardless of being valid or not).
// If we have pruned, then we can only say that HAVE_DATA implies nTx > 0
if (pindex->nStatus & BLOCK_HAVE_DATA) assert(pindex->nTx > 0);
}
if (pindex->nStatus & BLOCK_HAVE_UNDO) assert(pindex->nStatus & BLOCK_HAVE_DATA);
assert(((pindex->nStatus & BLOCK_VALID_MASK) >= BLOCK_VALID_TRANSACTIONS) == (pindex->nTx > 0)); // This is pruning-independent.
// All parents having had data (at some point) is equivalent to all parents being VALID_TRANSACTIONS, which is equivalent to nChainTx being set.
assert((pindexFirstNeverProcessed != NULL) == (pindex->nChainTx == 0)); // nChainTx != 0 is used to signal that all parent blocks have been processed (but may have been pruned).
assert(pindex->nHeight == nHeight); // nHeight must be consistent.
assert(pindex->pprev == NULL || pindex->nChainWork >= pindex->pprev->nChainWork); // For every block except the genesis block, the chainwork must be larger than the parent's.
assert(nHeight < 2 || (pindex->pskip && (pindex->pskip->nHeight < nHeight))); // The pskip pointer must point back for all but the first 2 blocks.
assert(pindexFirstNotTreeValid == NULL); // All mapBlockIndex entries must at least be TREE valid
if ((pindex->nStatus & BLOCK_VALID_MASK) >= BLOCK_VALID_TREE) assert(pindexFirstNotTreeValid == NULL); // TREE valid implies all parents are TREE valid
if ((pindex->nStatus & BLOCK_VALID_MASK) >= BLOCK_VALID_CHAIN) assert(pindexFirstNotChainValid == NULL); // CHAIN valid implies all parents are CHAIN valid
if ((pindex->nStatus & BLOCK_VALID_MASK) >= BLOCK_VALID_SCRIPTS) assert(pindexFirstNotScriptsValid == NULL); // SCRIPTS valid implies all parents are SCRIPTS valid
if (pindexFirstInvalid == NULL) {
// Checks for not-invalid blocks.
assert((pindex->nStatus & BLOCK_FAILED_MASK) == 0); // The failed mask cannot be set for blocks without invalid parents.
}
if (!CBlockIndexWorkComparator()(pindex, chainActive.Tip()) && pindexFirstNeverProcessed == NULL) {
if (pindexFirstInvalid == NULL) {
// If this block sorts at least as good as the current tip and
// is valid and we have all data for its parents, it must be in
// setBlockIndexCandidates. chainActive.Tip() must also be there
// even if some data has been pruned.
if (pindexFirstMissing == NULL || pindex == chainActive.Tip()) {
assert(setBlockIndexCandidates.count(pindex));
}
// If some parent is missing, then it could be that this block was in
// setBlockIndexCandidates but had to be removed because of the missing data.
// In this case it must be in mapBlocksUnlinked -- see test below.
}
} else { // If this block sorts worse than the current tip or some ancestor's block has never been seen, it cannot be in setBlockIndexCandidates.
// Allow exceptions from under-length message on vRecv
LogPrintf("%s(%s, %u bytes): Exception '%s' caught, normally caused by a message being shorter than its stated length\n", __func__, SanitizeString(strCommand), nMessageSize, e.what());
bool fFetch = state.fPreferredDownload || (nPreferredDownload == 0 && !pto->fClient && !pto->fOneShot); // Download if this is a nice peer, or we have no nice peers and this one might do.
if (!state.fSyncStarted && !pto->fClient && !fImporting && !fReindex) {
// Only actively request headers from a single peer, unless we're close to today.