[Libevent-users] [PATCH] signal.c, evsignal.h: properly save/restore previous signal handlers and fix memory stomp

[Christopher Layne]

On Fri, Nov 09, 2007 at 04:38:43PM -0800, Scott Lamb wrote:
> >Fix in same, or sweep up in a later patch? How many other places are
> >there where we're not currently checking the return value of
> >event_add()? If there are more than this, we might as well just do it
> >separately.
> >
> >-cl
> 
> Looks like there are a number of others:
> 
> * evsignal_cb <- evsignal_add() should probably be using EV_PERSIST so 
> this call is unnecessary

Yep.

> * bufferevent_read_cb
> * bufferevent_read_pressure_cb
> * bufferevent_write_cb
> * bufferevent_write
> * evdns_add_server_port
> * evdns_server_request_respond
> * evhttp_add_event
> * evhttp_connection_start_detectclose
> * evhttp_bind_socket
> 
> Most look straightforward to fix, but I'm not sure how the callbacks 
> should indicate error.
> 
> There are also several unchecked event_del() calls, but I think it's 
> safe to assume those will fail only on logic error.

I've had a couple of ideas running around in my head of a -DSTRICT type
setup for libevent in general. But then again, maybe these should be just
checked for error as normal - I'm sure more than one person has spent a few
hours tracking down a bunk fd they accidentally reused.

-cl