[QPID-2368] Exception Thrown at qpid/sys/epoll/EpollPoller.cpp:254 Leaves Orphan File Descriptor

• Type: Bug
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: 0.5
• Component/s: C++ Client
• Labels: leak

Environment

c++ client

• Assignee: Andrew Stitcher
• Reporter: Jason Schlauch
• Created: 28/Jan/10 02:00
• Updated: 24/Apr/13 13:01

Description

While researching JIRA QPID-2367 I noticed a pileup of file descriptors in /proc/PID/fd. I traced the creation of these descriptors back to this chunk of code in qpid/sys/epoll/EpollPoller.cpp:

244 PollerPrivate() :
245 epollFd(::epoll_create(DefaultFds)),
246 isShutdown(false)

{ 247 QPID_POSIX_CHECK(epollFd); 248 ::sigemptyset(&sigMask); 249 // Add always readable fd into our set (but not listening to it yet) 250 ::epoll_event epe; 251 epe.events = 0; 252 epe.data.u64 = 0; 253 QPID_POSIX_CHECK(::epoll_ctl(epollFd, EPOLL_CTL_ADD, alwaysReadableFd, &epe)); 254 }

The problem is with the second QPID_POSIX_CHECK – a macro that throws an exception. If an exception is thrown then the file descriptor allocated by epollFd(::epoll_create(DefaultFds)) is left dangling. A ::close(epollFd) would be needed in the catch() block to free it.

There are a number of functions with a similar design in EpollPoller.cpp that might be similarly affected.