Hi Evgeny,
Seems fixed on my side. I enforced single call of MHD_run. But I added a special treatment to enforce call to MHD_run even if MHD_get_timeout returned a timeout different of zero. This last point was discussed in the ML thread https://lists.gnu.org/archive/html/libmicrohttpd/2020-12/msg00017.html It could be of great advantage that MHD_get_timeout returns valuable value and also to have a version of MHD_run with a timeout (0 in my case) and returning a value indicating if it has to be called again for pending actions. Thank you for your help. Best regards José On Fri, 24 Sep 2021 14:56:36 +0200 José Bollo <jo...@nonadev.net> wrote: > Hi Evgeny, Hi all, > > Firstly, protecting MHD_run made the job, the crash disappears and > valgrind is happy. Thank you for that efficient support. > > Secundly, I'm still seeing and investigating an issue. Sometime, the > queued response (MHD_queue_response) is not sent. Here again, I think > that it is a race condition. The issue is surely on my side. > > Then some responses to your questions below. > > [snip] > > > >>> > > >>> flags = MHD_USE_EPOLL > > >>> | MHD_ALLOW_UPGRADE > > >>> | MHD_USE_TCP_FASTOPEN > > >>> | MHD_USE_NO_LISTEN_SOCKET > > >>> | MHD_ALLOW_SUSPEND_RESUME; > > >> > > >> Do you use suspend/resume of connections? > > > > > > yes for websocket upgrade but it is not relevant in the case. > > > > Don't you use MHD built-in "upgrade" functions? > > Good question. I had not noticed before: I have both options > MHD_ALLOW_UPGRADE and MHD_ALLOW_SUSPEND_RESUME. When I first > implemented websocket using MHD, I used the suspend/resume behaviour. > Is it still needed? I am now using MHD_create_response_for_upgrade for > that purpose. > > However, at the moment, the program suspend the connection for the > time it processes the request. That is the reason way MHD_run were > called from multiple threads. > > [snip] > > > Please share you results. > > We are close to releasing the next MHD version and want to make > > sure there are no know bugs in the code. > > Still investigating one issue. > > > I'm wondering, why do you run the same MHD instance in different > > threads? Every MHD_run() processes *all* connections served by > > particular MHD instance. This looks like work duplication (or > > multiplication). If you process specific connections by each thread > > and you add connections to MHD by MHD_add_connection(), just use > > thread-specific MHD instance so you will always know which > > connections are processed by MHD_run(). > > I could answer but here is what I prefer to write. > > I also think that if every one made same choices the world would be > peaceful. But new problems, new solutions, new men, new ideas, ... Why > have you written MHD in C and not in PASCAL? >
