如何跨插件共享boost :: asio :: io_service [模块]

Question

I would like to implement a single threaded application which also provides a plugin/module API. My application is using a static io_service instantiated/initialized in a class method. It might be called a singleton by some. Would it be a good idea to make this available to the plugin implementors?

boost::io_service& SomeClass::IOS()
{
  static boost::io_service ios;
  return ios;
}

First I thought of allowing the plugins to provide only file descriptors and the application wrapping them as stream_descriptor objects but this would prevent the io_object specific functionalities provided by boost; this is the reason I thought of providing the static io_service to the plugin implementors and restricting them to using io_object instances only.

Answer 1

I think there's no problem in exposing directly io_service as a singleton, if your architecture is based on boost::asio .

The issues about ABI are common to every C++ plugin architectue, and not specific to boost::asio . So, wrapping the io_service (as suggested by Richard) is not a solution to this problem, but just a way to hide the decision to use asio .

BTW: I guess you want to allow the plugins to manage I/O through asio , and the main application dispatch the tasks, so it wouldn't be enough for your wrapper to expose post and dispatch (useless for the plugins), you should instead provide eg sockets and other I/O methods.