asset database::match( const call_order_object& call,
const force_settlement_object& settle,
const price& match_price,
asset max_settlement )
{ try {
FC_ASSERT(call.get_debt().asset_id == settle.balance.asset_id );
FC_ASSERT(call.debt > 0 && call.collateral > 0 && settle.balance.amount > 0);
auto settle_for_sale = std::min(settle.balance, max_settlement);
auto call_debt = call.get_debt();
asset call_receives = std::min(settle_for_sale, call_debt);
asset call_pays = call_receives * match_price;
asset settle_pays = call_receives;
asset settle_receives = call_pays;
/**
* If the least collateralized call position lacks sufficient
* collateral to cover at the match price then this indicates a black
* swan event according to the price feed, but only the market
* can trigger a black swan. So now we must cancel the forced settlement
* object.
*/
GRAPHENE_ASSERT( call_pays < call.get_collateral(), black_swan_exception, "" );
assert( settle_pays == settle_for_sale || call_receives == call.get_debt() );
fill_order(call, call_pays, call_receives);
fill_order(settle, settle_pays, settle_receives);
return call_receives;
} FC_CAPTURE_AND_RETHROW( (call)(settle)(match_price)(max_settlement) ) }
bool database::fill_order( const call_order_object& order, const asset& pays, const asset& receives )
{ try {
//idump((pays)(receives)(order));
FC_ASSERT( order.get_debt().asset_id == receives.asset_id );
FC_ASSERT( order.get_collateral().asset_id == pays.asset_id );
FC_ASSERT( order.get_collateral() >= pays );
optional<asset> collateral_freed;
modify( order, [&]( call_order_object& o ){
o.debt -= receives.amount;
o.collateral -= pays.amount;
if( o.debt == 0 )
{
collateral_freed = o.get_collateral();
o.collateral = 0;
}
});
const asset_object& mia = receives.asset_id(*this);
assert( mia.is_market_issued() );
const asset_dynamic_data_object& mia_ddo = mia.dynamic_asset_data_id(*this);
modify( mia_ddo, [&]( asset_dynamic_data_object& ao ){
//idump((receives));
ao.current_supply -= receives.amount;
});
const account_object& borrower = order.borrower(*this);
if( collateral_freed || pays.asset_id == asset_id_type() )
{
const account_statistics_object& borrower_statistics = borrower.statistics(*this);
if( collateral_freed )
adjust_balance(borrower.get_id(), *collateral_freed);
modify( borrower_statistics, [&]( account_statistics_object& b ){
if( collateral_freed && collateral_freed->amount > 0 )
b.total_core_in_orders -= collateral_freed->amount;
if( pays.asset_id == asset_id_type() )
b.total_core_in_orders -= pays.amount;
assert( b.total_core_in_orders >= 0 );
});
}
assert( pays.asset_id != receives.asset_id );
push_applied_operation( fill_order_operation{ order.id, order.borrower, pays, receives, asset(0, pays.asset_id) } );
if( collateral_freed )
remove( order );
return collateral_freed.valid();
} FC_CAPTURE_AND_RETHROW( (order)(pays)(receives) ) }
asset database::match( const call_order_object& call, const force_settlement_object& settle, const price& match_price,
asset max_settlement )
{
assert(call.get_debt().asset_id == settle.balance.asset_id );
assert(call.debt > 0 && call.collateral > 0 && settle.balance.amount > 0);
auto settle_for_sale = std::min(settle.balance, max_settlement);
auto call_debt = call.get_debt();
asset call_receives = std::min(settle_for_sale, call_debt),
call_pays = call_receives * match_price,
settle_pays = call_receives,
settle_receives = call_pays;
assert( settle_pays == settle_for_sale || call_receives == call.get_debt() );
fill_order(call, call_pays, call_receives);
fill_order(settle, settle_pays, settle_receives);
return call_receives;
}
