Ticket #9058: with_lock_guard_usage.2.cpp

// (C) Copyright 2013 Ruslan Baratov
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

//  See www.boost.org/libs/thread for documentation.

#include <iostream>
#include <boost/bind.hpp>
#include <boost/thread/mutex.hpp>
#include <boost/thread/with_lock_guard.hpp>

void func_with_0_arg() {
  std::cout << __FUNCTION__ << std::endl;
}

void func_with_1_arg(int arg_1) {
  std::cout << __FUNCTION__ << ": " << arg_1 << std::endl;
}

bool func_with_2_arg(int arg_1, bool arg_2) {
  std::cout << __FUNCTION__ << ": " << arg_1 << ", " << arg_2 << std::endl;
  return !arg_2;
}

int func_with_3_arg(int arg_1, bool arg_2, const char* arg_3) {
  std::cout << __FUNCTION__ << ": " << arg_1 << ", " << arg_2 << ", ";
  std::cout << "<" << arg_3 << ">" << std::endl;
  return 12;
}

const char* func_with_4_arg(int arg_1, bool arg_2, int* arg_3, int& arg_4) {
  std::cout << __FUNCTION__ << ": " << arg_1 << ", " << arg_2 << std::endl;
  *arg_3 = 128;
  arg_4 = 456;
  return "hello";
}

void example() {
  boost::mutex m;

  boost::with_lock_guard(m, func_with_0_arg);
  boost::with_lock_guard(m, func_with_1_arg, 3);
  bool res2 = boost::with_lock_guard(m, func_with_2_arg, 3, true);
  std::cout << "res2 = " << res2 << std::endl;

  int arg1 = 13;
  const char* mes = "message for func with 3 arg";
  int res3 = boost::with_lock_guard(m, func_with_3_arg, arg1, false, mes);
  std::cout << "res3 = " << res3 << std::endl;

  int arg3 = 0;
  int arg4 = 0;
  const char* res4 = boost::with_lock_guard(
      m,
      func_with_4_arg,
      23,
      false,
      &arg3,
      boost::ref(arg4)
  );
  std::cout << "res4 = <" << res4 << ">, arg3 = " << arg3 <<
      ", arg4 = " << arg4 << std::endl;
}

class Foo {
 public:
  Foo(int value): value_(value) {
  }

  int func(int a, int b) {
    return a + b + value_;
  }

  int func_ref(int& a) {
    a = 133;
    return 34;
  }

 private:
  int value_;
};

void example_bind() {
  boost::mutex m;
  Foo foo(2);

  int res_bind = boost::with_lock_guard(
      m,
      boost::bind(&Foo::func, foo, 1, 31)
  );
  std::cout << "res_bind = " << res_bind << std::endl;

  int a = 0;
  int res_bind_ref = boost::with_lock_guard(
      m,
      boost::bind(&Foo::func_ref, foo, boost::ref(a))
  );
  std::cout << "res_bind_ref = " << res_bind_ref << ", " << a << std::endl;
}

#if defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
void example_variadic_templates() {
  std::cout << "C++11 variadic templates disabled" << std::endl;
}

void example_lambda() {
  std::cout << "C++11 lambda disabled" << std::endl;
}
#else
int func_with_5_args(int a1, char a2, int& a3, bool* a4, bool a5) {
  std::cout << __FUNCTION__ << ": " <<
      a1 << ", <" << a2 << ">, " << a5 << std::endl;
  a3 = 135;
  *a4 = false;
  return 45;
}

int func_with_6_args(int a1, char a2, int& a3, bool* a4, int&& a5, bool a6) {
  std::cout << __FUNCTION__ << ": " << a1 << ", <" << a2 << ">, " <<
      a5 << ", " << a6 << std::endl;
  a3 = 200;
  *a4 = true;
  return 888;
}

void example_variadic_templates() {
  boost::mutex m;

  int a3 = 0;
  bool a4 = true;
  int res5 = boost::with_lock_guard(
      m, func_with_5_args, 12, 'x', a3, &a4, false
  );
  std::cout << "res5 = " << res5 << ", " << a3 << ", " << a4 << std::endl;

  int res6 = boost::with_lock_guard(
      m, func_with_6_args, 12, 'N', a3, &a4, 2, false
  );
  std::cout << "res6 = " << res6 << ", " << a3 << ", " << a4 << std::endl;

  int a5 = 13;
  int res6_move = boost::with_lock_guard(
      m, func_with_6_args, 12, 'N', a3, &a4, boost::move(a5), false
  );
  std::cout << "res6(move) = " << res6_move << ", " <<
      a3 << ", " << a4 << std::endl;
}

void example_lambda() {
  boost::mutex m;
  int res_lambda = boost::with_lock_guard(
      m,
      [](int a) {
        return a + 3;
      },
      13
  );
  std::cout << "res lambda = " << res_lambda << std::endl;
}
#endif

int main() {
  std::cout << std::boolalpha;
  example();
  example_bind();
  example_lambda();
  example_variadic_templates();
  return 0;
}