JMutex.cc

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#include "JLang/JMutex.hh"
#include <iostream>
#include <stdexcept>
#include <cstdlib>

#include "Jeep/JParser.hh"
#include "Jeep/JMessage.hh"


/**
 * \author cpellegrino
 */

using namespace JPP;

void withdraw(int& account, int amount)
{
  if (amount < 0)
    throw std::runtime_error("Wrong amount!");

  if (account < amount)
    throw std::runtime_error("Your account can't provide the requested amount!");

  account -= amount;
}

void deposit(int& account, int amount)
{
  if (amount < 0)
    throw std::runtime_error("Wrong amount!");

  account += amount;
}

int main(int argc, char **argv)
{
  using namespace std;

  int debug;

  try {

    JParser<> zap("Example program to test mutex messaging.");

    zap['d'] = make_field(debug)     = 0;

    zap(argc, argv);
  }
  catch(const exception &error) {
    FATAL(error.what() << endl);
  }

  JMutex mutex;
  int credit_card = 0;

  cout << "Trying to deposit 1000 eur\n";

  {
    JMutex::JScopedLock lock(mutex);
    deposit(credit_card, 1000);
  }

  cout << "Trying to put a negative amount\n";

  try {
    JMutex::JScopedLock lock(mutex);
    deposit(credit_card, -200);
  } catch (runtime_error const& e) {
    cout << e.what() << '\n';
  }

  cout << "Let the wife do shopping\n";

  try {
    while (credit_card) {
      JMutex::JScopedLock lock(mutex);

      int const cost = rand() % 100;
      cout << "Paying " << cost << "for something\n";
      withdraw(credit_card, cost);
    }
  } catch (runtime_error const& e) {
    cout << e.what() << '\n';
  }
}