[Boost-users] Is boost::asio::io_service thread safety?

Subject: [Boost-users] Is boost::asio::io_service thread safety?
From: 文凯 (wenkai1987_at_[hidden])
Date: 2012-04-07 03:10:32

My code like this:

#include <iostream>
#include <map>
#include <boost/asio.hpp>
#include <boost/bind.hpp>
#include <boost/thread.hpp>
#include <boost/date_time/posix_time/posix_time.hpp>

namespace ba = boost::asio;
namespace bp = boost::posix_time;

typedef std::map<int, ba::deadline_timer*> timer_map;

timer_map g_timers;
boost::mutex g_timers_lock;

ba::io_service g_ios;

void on_timer(int id) {
    {
            boost::mutex::scoped_lock lock(g_timers_lock);
            timer_map::iterator it = g_timers.find(id);
            assert(it != g_timers.end());
            g_timers.erase(id);
    }

    // std::cout << "delete timer " << id << std::endl;
}

int main(void) {
    boost::thread trd(boost::bind(&ba::io_service::run, &g_ios));
    trd.detach();

    int count = 0;
    for (;;) {
            for (int i = 0; i < 100; i++) {
                    ba::deadline_timer* pt = new
ba::deadline_timer(g_ios, bp::seconds(1));
                    pt->async_wait(boost::bind(&on_timer, count));

                    boost::mutex::scoped_lock lock(g_timers_lock);
                    g_timers.insert(std::make_pair(count++, pt));
            }

            usleep(20000);
    }

    return 0;
}

==================================
I know, I should lock the g_timers, but should I lock the g_ios? I
mean these lines:

   ba::deadline_timer* pt = new ba::deadline_timer(g_ios, bp::seconds(1));
   pt->async_wait(boost::bind(&on_timer, count));

Are thread safety? It reference the g_ios, and will it call
g_ios.add_job(this_timer) ..etc.. ?

--
Cheers & KaiWen