From 88d92c87ce31625c6d633246cf70ec440d579945 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?P=C5=99emysl=20Janouch?=
Date: Thu, 25 Sep 2014 22:38:52 +0200
Subject: [PATCH] Fix the optimization
It wasn't all that easy.
---
utils.c | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/utils.c b/utils.c
index 019fcdd..6d7198d 100644
--- a/utils.c
+++ b/utils.c
@@ -1056,6 +1056,7 @@ struct poller
{
int epoll_fd; ///< The epoll FD
struct poller_fd **fds; ///< Information associated with each FD
+ int *dummy; ///< For poller_remove_from_dispatch()
struct epoll_event *revents; ///< Output array for epoll_wait()
size_t len; ///< Number of polled descriptors
size_t alloc; ///< Number of entries allocated
@@ -1076,6 +1077,7 @@ poller_init (struct poller *self)
self->len = 0;
self->alloc = POLLER_MIN_ALLOC;
self->fds = xcalloc (self->alloc, sizeof *self->fds);
+ self->dummy = xcalloc (self->alloc, sizeof *self->dummy);
self->revents = xcalloc (self->alloc, sizeof *self->revents);
self->revents_len = 0;
@@ -1096,6 +1098,7 @@ poller_free (struct poller *self)
xclose (self->epoll_fd);
free (self->fds);
+ free (self->dummy);
free (self->revents);
}
@@ -1112,6 +1115,8 @@ poller_ensure_space (struct poller *self)
(self->revents, sizeof *self->revents, self->alloc);
self->fds = xreallocarray
(self->fds, sizeof *self->fds, self->alloc);
+ self->dummy = xreallocarray
+ (self->dummy, sizeof *self->dummy, self->alloc);
}
static short
@@ -1174,7 +1179,15 @@ poller_remove_from_dispatch (struct poller *self, const struct poller_fd *fd)
struct epoll_event key = { .data.ptr = (void *) fd }, *fd_event;
if ((fd_event = bsearch (&key, self->revents,
self->revents_len, sizeof *self->revents, poller_compare_fds)))
+ {
fd_event->events = -1;
+
+ // Don't let any further bsearch()'s touch possibly freed memory
+ int *dummy = self->dummy + (fd_event - self->revents);
+ *dummy = fd->fd;
+ fd_event->data.ptr =
+ (uint8_t *) dummy - offsetof (struct poller_fd, fd);
+ }
}
static void