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Diffstat (limited to '3rdparty/asio/src/examples/cpp03/timers/tick_count_timer.cpp')
-rw-r--r-- | 3rdparty/asio/src/examples/cpp03/timers/tick_count_timer.cpp | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/3rdparty/asio/src/examples/cpp03/timers/tick_count_timer.cpp b/3rdparty/asio/src/examples/cpp03/timers/tick_count_timer.cpp new file mode 100644 index 00000000000..8b98cfd2a54 --- /dev/null +++ b/3rdparty/asio/src/examples/cpp03/timers/tick_count_timer.cpp @@ -0,0 +1,123 @@ +// +// tick_count_timer.cpp +// ~~~~~~~~~~~~~~~~~~~~ +// +// Copyright (c) 2003-2016 Christopher M. Kohlhoff (chris at kohlhoff dot com) +// +// 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) +// + +#include <asio.hpp> +#include <ctime> +#include <iostream> + +#if defined(WIN32) +# include <windows.h> +#else +# error This example is for Windows only! +#endif + +struct tick_count_traits +{ + // The time type. This type has no constructor that takes a DWORD to ensure + // that the timer can only be used with relative times. + class time_type + { + public: + time_type() : ticks_(0) {} + private: + friend struct tick_count_traits; + DWORD ticks_; + }; + + // The duration type. According to the TimeTraits requirements, the duration + // must be a signed type. This means we can't handle durations larger than + // 2^31. + class duration_type + { + public: + duration_type() : ticks_(0) {} + duration_type(LONG ticks) : ticks_(ticks) {} + private: + friend struct tick_count_traits; + LONG ticks_; + }; + + // Get the current time. + static time_type now() + { + time_type result; + result.ticks_ = ::GetTickCount(); + return result; + } + + // Add a duration to a time. + static time_type add(const time_type& t, const duration_type& d) + { + time_type result; + result.ticks_ = t.ticks_ + d.ticks_; + return result; + } + + // Subtract one time from another. + static duration_type subtract(const time_type& t1, const time_type& t2) + { + // DWORD tick count values can wrap (see less_than() below). We'll convert + // to a duration by taking the absolute difference and adding the sign + // based on which is the "lesser" absolute time. + return duration_type(less_than(t1, t2) + ? -static_cast<LONG>(t2.ticks_ - t1.ticks_) + : static_cast<LONG>(t1.ticks_ - t2.ticks_)); + } + + // Test whether one time is less than another. + static bool less_than(const time_type& t1, const time_type& t2) + { + // DWORD tick count values wrap periodically, so we'll use a heuristic that + // says that if subtracting t1 from t2 yields a value smaller than 2^31, + // then t1 is probably less than t2. This means that we can't handle + // durations larger than 2^31, which shouldn't be a problem in practice. + return (t2.ticks_ - t1.ticks_) < static_cast<DWORD>(1 << 31); + } + + // Convert to POSIX duration type. + static boost::posix_time::time_duration to_posix_duration( + const duration_type& d) + { + return boost::posix_time::milliseconds(d.ticks_); + } +}; + +typedef asio::basic_deadline_timer< + DWORD, tick_count_traits> tick_count_timer; + +void handle_timeout(const asio::error_code&) +{ + std::cout << "handle_timeout\n"; +} + +int main() +{ + try + { + asio::io_context io_context; + + tick_count_timer timer(io_context, 5000); + std::cout << "Starting synchronous wait\n"; + timer.wait(); + std::cout << "Finished synchronous wait\n"; + + timer.expires_from_now(5000); + std::cout << "Starting asynchronous wait\n"; + timer.async_wait(&handle_timeout); + io_context.run(); + std::cout << "Finished asynchronous wait\n"; + } + catch (std::exception& e) + { + std::cout << "Exception: " << e.what() << "\n"; + } + + return 0; +} |