void database::_apply_block( const signed_block& next_block )
{ try {
uint32_t next_block_num = next_block.block_num();
uint32_t skip = get_node_properties().skip_flags;
_applied_ops.clear();
FC_ASSERT( (skip & skip_merkle_check) || next_block.transaction_merkle_root == next_block.calculate_merkle_root(), "", ("next_block.transaction_merkle_root",next_block.transaction_merkle_root)("calc",next_block.calculate_merkle_root())("next_block",next_block)("id",next_block.id()) );
const witness_object& signing_witness = validate_block_header(skip, next_block);
const auto& global_props = get_global_properties();
const auto& dynamic_global_props = get<dynamic_global_property_object>(dynamic_global_property_id_type());
bool maint_needed = (dynamic_global_props.next_maintenance_time <= next_block.timestamp);
_current_block_num = next_block_num;
_current_trx_in_block = 0;
for( const auto& trx : next_block.transactions )
{
/* We do not need to push the undo state for each transaction
* because they either all apply and are valid or the
* entire block fails to apply. We only need an "undo" state
* for transactions when validating broadcast transactions or
* when building a block.
*/
apply_transaction( trx, skip );
++_current_trx_in_block;
}
update_global_dynamic_data(next_block);
update_signing_witness(signing_witness, next_block);
update_last_irreversible_block();
// Are we at the maintenance interval?
if( maint_needed )
perform_chain_maintenance(next_block, global_props);
create_block_summary(next_block);
clear_expired_transactions();
clear_expired_proposals();
clear_expired_orders();
update_expired_feeds();
update_withdraw_permissions();
// n.b., update_maintenance_flag() happens this late
// because get_slot_time() / get_slot_at_time() is needed above
// TODO: figure out if we could collapse this function into
// update_global_dynamic_data() as perhaps these methods only need
// to be called for header validation?
update_maintenance_flag( maint_needed );
update_witness_schedule();
if( !_node_property_object.debug_updates.empty() )
apply_debug_updates();
// notify observers that the block has been applied
applied_block( next_block ); //emit
_applied_ops.clear();
notify_changed_objects();
} FC_CAPTURE_AND_RETHROW( (next_block.block_num()) ) }
bool database::_push_block(const signed_block& new_block)
{ try {
uint32_t skip = get_node_properties().skip_flags;
if( !(skip&skip_fork_db) )
{
/// TODO: if the block is greater than the head block and before the next maitenance interval
// verify that the block signer is in the current set of active witnesses.
shared_ptr<fork_item> new_head = _fork_db.push_block(new_block);
//If the head block from the longest chain does not build off of the current head, we need to switch forks.
if( new_head->data.previous != head_block_id() )
{
//If the newly pushed block is the same height as head, we get head back in new_head
//Only switch forks if new_head is actually higher than head
if( new_head->data.block_num() > head_block_num() )
{
wlog( "Switching to fork: ${id}", ("id",new_head->data.id()) );
auto branches = _fork_db.fetch_branch_from(new_head->data.id(), head_block_id());
// pop blocks until we hit the forked block
while( head_block_id() != branches.second.back()->data.previous )
pop_block();
// push all blocks on the new fork
for( auto ritr = branches.first.rbegin(); ritr != branches.first.rend(); ++ritr )
{
ilog( "pushing blocks from fork ${n} ${id}", ("n",(*ritr)->data.block_num())("id",(*ritr)->data.id()) );
optional<fc::exception> except;
try {
undo_database::session session = _undo_db.start_undo_session();
apply_block( (*ritr)->data, skip );
_block_id_to_block.store( (*ritr)->id, (*ritr)->data );
session.commit();
}
catch ( const fc::exception& e ) { except = e; }
if( except )
{
wlog( "exception thrown while switching forks ${e}", ("e",except->to_detail_string() ) );
// remove the rest of branches.first from the fork_db, those blocks are invalid
while( ritr != branches.first.rend() )
{
_fork_db.remove( (*ritr)->data.id() );
++ritr;
}
_fork_db.set_head( branches.second.front() );
// pop all blocks from the bad fork
while( head_block_id() != branches.second.back()->data.previous )
pop_block();
// restore all blocks from the good fork
for( auto ritr = branches.second.rbegin(); ritr != branches.second.rend(); ++ritr )
{
auto session = _undo_db.start_undo_session();
apply_block( (*ritr)->data, skip );
_block_id_to_block.store( new_block.id(), (*ritr)->data );
session.commit();
}
throw *except;
}
}
return true;
}
else return false;
}
}
try {
auto session = _undo_db.start_undo_session();
apply_block(new_block, skip);
_block_id_to_block.store(new_block.id(), new_block);
session.commit();
} catch ( const fc::exception& e ) {
elog("Failed to push new block:\n${e}", ("e", e.to_detail_string()));
_fork_db.remove(new_block.id());
throw;
}
return false;
} FC_CAPTURE_AND_RETHROW( (new_block) ) }
/**
* Pushes the block into the fork database and caches it if it doesn't link
*
*/
shared_ptr<fork_item> fork_database::push_block(const signed_block& b)
{
auto item = std::make_shared<fork_item>(b);
try {
_push_block(item);
}
catch ( const unlinkable_block_exception& e )
{
wlog( "Pushing block to fork database that failed to link: ${id}, ${num}", ("id",b.id())("num",b.block_num()) );
wlog( "Head: ${num}, ${id}", ("num",_head->data.block_num())("id",_head->data.id()) );
throw;
_unlinked_index.insert( item );
}
return _head;
}
fork_item( signed_block d )
:num(d.block_num()),id(d.id()),data( std::move(d) ){}
block_message(const signed_block &blk)
: block(blk), block_id(blk.id()) {
}
