bool transaction::read_from_disk(
db_tx & tx_db, const point_out & previous_out, transaction_index & tx_index
)
{
set_null();
if (
tx_db.read_transaction_index(
previous_out.get_hash(), tx_index) == false
)
{
log_debug(
"Transaction failed to read from disk, read transaction index "
"failed, previous out = " <<
previous_out.get_hash().to_string().substr(0, 20) << "."
);
return false;
}
if (read_from_disk(tx_index.get_transaction_position()) == false)
{
log_debug(
"Transaction failed to read from disk, read from disk failed."
);
return false;
}
if (previous_out.n() >= m_transactions_out.size())
{
log_debug(
"Transaction failed to read from disk, n is greater than outputs."
);
set_null();
return false;
}
return true;
}
bool transaction::fetch_inputs(
db_tx & dbtx, const std::map<sha256, transaction_index> & test_pool,
const bool & best_block, const bool & create_block,
transaction::previous_t & inputs, bool & invalid
)
{
/**
* If the transaction is invalid this will be set to true.
*/
invalid = false;
/**
* Coinbase transactions have no inputs to fetch.
*/
if (is_coin_base())
{
return true;
}
for (auto i = 0; i < m_transactions_in.size(); i++)
{
auto previous_out = m_transactions_in[i].previous_out();
if (inputs.count(previous_out.get_hash()) > 0)
{
continue;
}
/**
* Read the transaction index.
*/
auto & tx_index = inputs[previous_out.get_hash()].first;
bool found = true;
if (
(best_block || create_block) &&
test_pool.count(previous_out.get_hash()) > 0
)
{
/**
* Get the transaction index from the current proposed changes.
*/
tx_index = test_pool.find(previous_out.get_hash())->second;
}
else
{
/**
* Read transaction index from transaction database.
*/
found = dbtx.read_transaction_index(
previous_out.get_hash(), tx_index
);
}
if (found == false && (best_block || create_block))
{
if (create_block)
{
return false;
}
else
{
log_error(
"Transaction " << get_hash().to_string().substr(0, 10) <<
" previous transaction " <<
previous_out.get_hash().to_string().substr(0, 10) <<
" index entry not found."
);
return false;
}
}
/**
* Read previous transaction.
*/
auto & tx_prev = inputs[previous_out.get_hash()].second;
if (
found == false ||
tx_index.get_transaction_position() == transaction_position(1, 1, 1)
)
{
if (
transaction_pool::instance().exists(
previous_out.get_hash()) == false
)
{
log_debug(
"Transaction failed to fetch inputs, " <<
get_hash().to_string().substr(0, 10) <<
" pool previous transaction not found " <<
previous_out.get_hash().to_string().substr(0, 10) << "."
);
return false;
}
tx_prev = transaction_pool::instance().lookup(
previous_out.get_hash()
);
if (found == false)
{
tx_index.spent().resize(tx_prev.transactions_out().size());
}
}
else
{
/**
* Read previous transaction from disk.
*/
if (
tx_prev.read_from_disk(
tx_index.get_transaction_position()) == false
)
{
log_error(
"Transaction " << get_hash().to_string().substr(0, 10) <<
" failed to read previous transaction " <<
previous_out.get_hash().to_string().substr(0, 10) <<
" from disk."
);
return false;
}
}
}
/**
* Check that all previous out's n indexes are valid.
*/
for (auto i = 0; i < m_transactions_in.size(); i++)
{
const auto & previous_out = m_transactions_in[i].previous_out();
assert(inputs.count(previous_out.get_hash()) != 0);
auto & tx_index = inputs[previous_out.get_hash()].first;
auto & tx_prev = inputs[previous_out.get_hash()].second;
if (
previous_out.n() >= tx_prev.transactions_out().size() ||
previous_out.n() >= tx_index.spent().size()
)
{
/**
* Revisit this if/when transaction replacement is implemented
* and allows adding inputs.
*/
invalid = true;
log_error(
"Transaction " << get_hash().to_string().substr(0, 10) <<
" previous out n out of range " << previous_out.n() << ":" <<
tx_prev.transactions_out().size() << ":" <<
tx_index.spent().size() << " previous transaction " <<
previous_out.get_hash().to_string().substr(0, 10) << "\n" <<
tx_prev.to_string() << "."
);
return false;
}
}
return true;
}
bool transaction::disconnect_inputs(db_tx & tx_db)
{
/**
* Relinquish previous transactions' spent pointers.
*/
if (is_coin_base() == false)
{
for (auto & i : m_transactions_in)
{
auto prev_out = i.previous_out();
/**
* Get previous transaction index from disk.
*/
transaction_index txindex;
if (
tx_db.read_transaction_index(
prev_out.get_hash(), txindex) == false
)
{
log_error(
"Transaction disconnect_inputs failed, "
"read_transaction_index failed."
);
return false;
}
if (prev_out.n() >= txindex.spent().size())
{
log_error(
"Transaction disconnect_inputs failed, previous"
" out n is out of range"
);
return false;
}
/**
* Mark outpoint as not spent.
*/
txindex.spent()[prev_out.n()].set_null();
/**
* Write back.
*/
if (
tx_db.update_transaction_index(
prev_out.get_hash(), txindex) == false
)
{
log_error(
"Transaction disconnect_inputs failed, "
"update_transaction_index failed."
);
return false;
}
}
}
/**
* Remove transaction from the index. This can fail if a duplicate of this
* transaction was in a chain that got reorganized away. This is only
* possible if this transaction was completely spent, so erasing it would
* be a no-op anyway.
*/
tx_db.erase_transaction_index(*this);
return true;
}