diff options
Diffstat (limited to '3rdparty/asio/src/examples/cpp14/executors/async_2.cpp')
-rw-r--r-- | 3rdparty/asio/src/examples/cpp14/executors/async_2.cpp | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/3rdparty/asio/src/examples/cpp14/executors/async_2.cpp b/3rdparty/asio/src/examples/cpp14/executors/async_2.cpp new file mode 100644 index 00000000000..b39156dcb23 --- /dev/null +++ b/3rdparty/asio/src/examples/cpp14/executors/async_2.cpp @@ -0,0 +1,68 @@ +#include <asio/ts/executor.hpp> +#include <asio/thread_pool.hpp> +#include <iostream> +#include <string> + +using asio::bind_executor; +using asio::dispatch; +using asio::get_associated_executor; +using asio::make_work_guard; +using asio::post; +using asio::thread_pool; + +// A function to asynchronously read a single line from an input stream. +template <class Handler> +void async_getline(std::istream& is, Handler handler) +{ + // Create executor_work for the handler's associated executor. + auto work = make_work_guard(handler); + + // Post a function object to do the work asynchronously. + post([&is, work, handler=std::move(handler)]() mutable + { + std::string line; + std::getline(is, line); + + // Pass the result to the handler, via the associated executor. + dispatch(work.get_executor(), + [line=std::move(line), handler=std::move(handler)]() mutable + { + handler(std::move(line)); + }); + }); +} + +// A function to asynchronously read multiple lines from an input stream. +template <class Handler> +void async_getlines(std::istream& is, std::string init, Handler handler) +{ + // Get the final handler's associated executor. + auto ex = get_associated_executor(handler); + + // Use the associated executor for each operation in the composition. + async_getline(is, + bind_executor(ex, + [&is, lines=std::move(init), handler=std::move(handler)] + (std::string line) mutable + { + if (line.empty()) + handler(lines); + else + async_getlines(is, lines + line + "\n", std::move(handler)); + })); +} + +int main() +{ + thread_pool pool; + + std::cout << "Enter text, terminating with a blank line:\n"; + + async_getlines(std::cin, "", + bind_executor(pool, [](std::string lines) + { + std::cout << "Lines:\n" << lines << "\n"; + })); + + pool.join(); +} |