MainThreadMLscribe.cc

Go to the documentation of this file.

// ----------------------------------------------------------------------
//
// MainThreadMLscribe.cc
//
// Changes:
//
//

#include "FWCore/MessageService/interface/MainThreadMLscribe.h"
#include "FWCore/MessageService/interface/ThreadQueue.h"
#include "FWCore/MessageLogger/interface/ConfigurationHandshake.h"

namespace edm {
  namespace service {

    MainThreadMLscribe::MainThreadMLscribe(std::shared_ptr<ThreadQueue> tqp) : m_queue(tqp) {}

    MainThreadMLscribe::~MainThreadMLscribe() {}

    void MainThreadMLscribe::runCommand(MessageLoggerQ::OpCode opcode, void *operand) {
      if (MessageLoggerQ::handshaked(opcode)) {
        Place_for_passing_exception_ptr epp(new Pointer_to_new_exception_on_heap());
        ConfigurationHandshake h(operand, epp);
        void *v(static_cast<void *>(&h));
        Pointer_to_new_exception_on_heap ep;
        {
          std::unique_lock<std::mutex> sl(h.m);  // get lock
          m_queue->produce(opcode, v);
          // wait for result to appear (in epp)
          h.c.wait(sl);  // c.wait(sl) unlocks the scoped lock and sleeps till notified
          // ... and once the MessageLoggerScribe does h.c.notify_all() ...
          ep = *h.epp;
          // finally, release the scoped lock by letting it go out of scope
        }
        if (ep) {
          edm::Exception ex(*ep);
          throw ex;
        }
      } else {
        m_queue->produce(opcode, operand);
      }
    }  // runCommand

  }  // end of namespace service
}  // end of namespace edm