token_issue.cpp

void token::issue( const name& to, const asset& quantity, const string& memo )
{
    auto sym = quantity.symbol;
    check( sym.is_valid(), "invalid symbol name" );
    check( memo.size() <= 256, "memo has more than 256 bytes" );

    stats statstable( get_self(), sym.code().raw() );
    auto existing = statstable.find( sym.code().raw() );
    check( existing != statstable.end(), "token with symbol does not exist, create token before issue" );
    const auto& st = *existing;
    check( to == st.issuer, "tokens can only be issued to issuer account" );

    require_auth( st.issuer );
    check( quantity.is_valid(), "invalid quantity" );
    check( quantity.amount > 0, "must issue positive quantity" );

    check( quantity.symbol == st.supply.symbol, "symbol precision mismatch" );
    check( quantity.amount <= st.max_supply.amount - st.supply.amount, "quantity exceeds available supply");

    statstable.modify( st, same_payer, [&]( auto& s ) {
       s.supply += quantity;
    });

    add_balance( st.issuer, quantity, st.issuer );
}