// en.bitcoin.it/wiki/Protocol_documentation#getdata
// getdata can be used to retrieve transactions, but only if they are
// in the memory pool or relay set - arbitrary access to transactions
// in the chain is not allowed to avoid having clients start to depend
// on nodes having full transaction indexes (which modern nodes do not).
void responder::send_chain_tx(const code& ec, const transaction& tx,
const hash_digest& tx_hash, channel::ptr node)
{
if (ec == error::service_stopped)
return;
if (ec == error::not_found)
{
log::debug(LOG_RESPONDER)
<< "Transaction for [" << node->authority()
<< "] not in blockchain [" << encode_hash(tx_hash) << "]";
// It wasn't in the blockchain, so send notfound.
send_tx_not_found(tx_hash, node);
return;
}
if (ec)
{
log::error(LOG_RESPONDER)
<< "Failure fetching blockchain tx data for ["
<< node->authority() << "] " << ec.message();
node->stop(ec);
return;
}
send_tx(tx, tx_hash, node);
}
// We don't seem to be getting getdata requests.
void responder::receive_get_data(const code& ec, const get_data& packet,
channel::ptr node)
{
if (ec == error::channel_stopped)
return;
const auto peer = node->authority();
if (ec)
{
log::debug(LOG_RESPONDER)
<< "Failure in receive get data [" << peer << "] " << ec.message();
node->stop(ec);
return;
}
// Resubscribe to serve tx and blocks.
node->subscribe<message::get_data>(
std::bind(&responder::receive_get_data,
this, _1, _2, node));
log::debug(LOG_RESPONDER)
<< "Getdata BEGIN [" << peer << "] "
<< "txs (" << packet.count(inventory_type_id::transaction) << ") "
<< "blocks (" << packet.count(inventory_type_id::block) << ") "
<< "bloom (" << packet.count(inventory_type_id::filtered_block) << ")";
for (const auto& inventory: packet.inventories)
{
switch (inventory.type)
{
case inventory_type_id::transaction:
log::debug(LOG_RESPONDER)
<< "Transaction getdata for [" << peer << "] "
<< encode_hash(inventory.hash);
tx_pool_.fetch(inventory.hash,
std::bind(&responder::send_pool_tx,
this, _1, _2, inventory.hash, node));
break;
case inventory_type_id::block:
log::debug(LOG_RESPONDER)
<< "Block getdata for [" << peer << "] "
<< encode_hash(inventory.hash);
block_fetcher::fetch(blockchain_, inventory.hash,
std::bind(&responder::send_block,
this, _1, _2, inventory.hash, node));
break;
case inventory_type_id::error:
case inventory_type_id::none:
default:
log::debug(LOG_RESPONDER)
<< "Ignoring invalid getdata type for [" << peer << "]";
}
}
log::debug(LOG_RESPONDER)
<< "Getdata END [" << peer << "]";
}
void responder::send_pool_tx(const code& ec, const transaction& tx,
const hash_digest& tx_hash, channel::ptr node)
{
if (ec == error::service_stopped)
return;
if (ec == error::not_found)
{
log::debug(LOG_RESPONDER)
<< "Transaction for [" << node->authority()
<< "] not in mempool [" << encode_hash(tx_hash) << "]";
// It wasn't in the mempool, so relay the request to the blockchain.
blockchain_.fetch_transaction(tx_hash,
std::bind(&responder::send_chain_tx,
this, _1, _2, tx_hash, node));
return;
}
if (ec)
{
log::error(LOG_RESPONDER)
<< "Failure fetching mempool tx data for ["
<< node->authority() << "] " << ec.message();
node->stop(ec);
return;
}
send_tx(tx, tx_hash, node);
}
void session::handle_start(const code& ec, channel::ptr channel,
result_handler handle_started, result_handler handle_stopped)
{
// Must either stop or subscribe the channel for stop before returning.
if (ec)
channel->stop(ec);
else
channel->subscribe_stop(handle_stopped);
// This is the end of the registration sequence.
handle_started(ec);
}
void protocol::handle_handshake(const code& ec, channel::ptr node)
{
if (ec)
{
log_debug(LOG_PROTOCOL) << "Failure in peer handshake ["
<< node->address() << "] " << ec.message();
node->stop(ec);
return;
}
// Attach ping protocol to the new connection (until node stop event).
std::make_shared<protocol_ping>(node, pool_, timeouts_.heartbeat)->start();
// Attach address protocol to the new connection (until node stop event).
std::make_shared<protocol_address>(node, pool_, hosts_, self_)->start();
}
void session::handle_start(const code& ec, channel::ptr channel,
result_handler handle_started, result_handler handle_stopped)
{
// Must either stop or subscribe the channel for stop before returning.
// All closures must eventually be invoked as otherwise it is a leak.
// Therefore upon start failure expect start failure and stop callbacks.
if (ec)
{
channel->stop(ec);
handle_stopped(ec);
}
else
{
channel->subscribe_stop(
BIND_3(do_remove, _1, channel, handle_stopped));
}
// This is the end of the registration sequence.
handle_started(ec);
}
// Should we look in the orphan pool first?
void responder::send_block(const code& ec, const block& block,
const hash_digest& block_hash, channel::ptr node)
{
if (ec == error::service_stopped)
return;
if (ec == error::not_found)
{
log::debug(LOG_RESPONDER)
<< "Block for [" << node->authority()
<< "] not in blockchain [" << encode_hash(block_hash) << "]";
// It wasn't in the blockchain, so send notfound.
send_block_not_found(block_hash, node);
}
if (ec)
{
log::error(LOG_RESPONDER)
<< "Failure fetching block data for ["
<< node->authority() << "] " << ec.message();
node->stop(ec);
return;
}
const auto send_handler = [block_hash, node](const code& ec)
{
if (ec)
log::debug(LOG_RESPONDER)
<< "Failure sending block for ["
<< node->authority() << "]";
else
log::debug(LOG_RESPONDER)
<< "Sent block for [" << node->authority()
<< "] " << encode_hash(block_hash);
};
node->send(block, send_handler);
}
void session_batch::converge(const code& ec, channel::ptr channel,
atomic_counter_ptr counter, upgrade_mutex_ptr mutex,
channel_handler handler)
{
///////////////////////////////////////////////////////////////////////////
// Critical Section
mutex->lock_upgrade();
const auto initial_count = counter->load();
BITCOIN_ASSERT(initial_count <= batch_size_);
// Already completed, don't call handler.
if (initial_count == batch_size_)
{
mutex->unlock_upgrade();
//-----------------------------------------------------------------
if (!ec)
channel->stop(error::channel_stopped);
return;
}
const auto count = !ec ? batch_size_ : initial_count + 1;
const auto cleared = count == batch_size_;
//+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
mutex->unlock_upgrade_and_lock();
counter->store(count);
mutex->unlock();
///////////////////////////////////////////////////////////////////////
if (cleared)
{
// If the last connection attempt is an error, normalize the code.
const auto result = ec ? error::operation_failed : error::success;
handler(result, channel);
}
}
