kc3-lang/libevent

2009-05-12T18:27:45

Fix dangling pointer in epoll after epoll_recalc(). This is based on patch 2790759 from Kevin Springborn. His comments on sourceforge: Problem: The failure case is as follows: Event is added using epoll_add (a direct pointer is stored in the user_data section), epoll_recalc is called and the fds array is moved (invalidating the user_data pointer stored in epoll). epoll_dispatch is called for the added event and accesses evepoll based on the invalid pointer (set before the fds array was relocated). Solution: Dispatch has access to the epollop structure, so given the fd we can find the corresponding evepoll struct. Use data.fd instead of data.ptr and store the fd corresponding to the event. This way when epoll_recalc moves the fds array (and updates the fds array pointer in epollop), the evepoll calculation in dispatch still finds the valid evepoll struct. svn:r1282