ceph/src/boost/libs/asio/example/cpp11/executors/bank_account_2.cpp

   1 #include <boost/asio/execution.hpp>
   2 #include <boost/asio/static_thread_pool.hpp>
   3 #include <iostream>
   4
   5 using boost::asio::static_thread_pool;
   6 namespace execution = boost::asio::execution;
   7
   8 // Traditional active object pattern.
   9 // Member functions block until operation is finished.
  10
  11 class bank_account
  12 {
  13   int balance_ = 0;
  14   mutable static_thread_pool pool_{1};
  15
  16 public:
  17   void deposit(int amount)
  18   {
  19     execution::execute(
  20         boost::asio::require(pool_.executor(),
  21           execution::blocking.always),
  22         [this, amount]
  23         {
  24           balance_ += amount;
  25         });
  26   }
  27
  28   void withdraw(int amount)
  29   {
  30     execution::execute(
  31         boost::asio::require(pool_.executor(),
  32           execution::blocking.always),
  33         [this, amount]
  34         {
  35           if (balance_ >= amount)
  36             balance_ -= amount;
  37         });
  38   }
  39
  40   int balance() const
  41   {
  42     int result = 0;
  43     execution::execute(
  44         boost::asio::require(pool_.executor(),
  45           execution::blocking.always),
  46         [this, &result]
  47         {
  48           result = balance_;
  49         });
  50     return result;
  51   }
  52 };
  53
  54 int main()
  55 {
  56   bank_account acct;
  57   acct.deposit(20);
  58   acct.withdraw(10);
  59   std::cout << "balance = " << acct.balance() << "\n";
  60 }