[cups-devel] [UNKN] STR #4605: Busy loop when epoll is in use

[Tim Waugh]

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[STR New]

epoll_wait() will always wait for EPOLL_HUP even if event.events==0. This
causes a busy loop when a connection is closed just after this moment, in
scheduler/client.c:1980:

	if (httpGetState(con->http) == HTTP_STATE_POST_SEND)
	{
 /*
	  * Don't listen for activity until we decide to do something with this...
	  */

  cupsdAddSelect(httpGetFd(con->http), NULL, NULL, con);

This causes an event with event.events==0 to be added/modified with
epoll_ctl().

Original report:
  https://bugzilla.redhat.com/show_bug.cgi?id=1179596

Link: https://www.cups.org/str.php?L4605
Version: 2.0-current
Fix Version: 2.0.2
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