Robert Norris wrote:
Robert, Thanks for resending... No promises but I'll try to review this this week. Please, someone beat me to it.
Bill
[ I'm resending this, because I didn't get any responses to it the first time. ]
Attached is a patch that adds a function apr_pollset_update(). This updates the list of requested events for the descriptor in the underlying implementation for a descriptor that is already in a pollset.
It works well enough, but I'm not happy with it because it requires a search through the pollset (just as apr_pollset_remove() does). On a server with hundreds or thousands of descriptors in the set and changing events often, this might end up being too expensive.
The optimisation that I'd like to do is to maintain a pointer (by index or explicit) for each descriptor that points to the descriptors' underlying pollfd structure, and just use this. This would lose the ability to enter a socket into the set multiple times with different events, as is currently possible, but would eliminate the search.
The only problem with this is that such a pointer would really belong in apr_pollfd_t, except that its specific to the poll() implementation, and that type is not opaque. So I'd appreciate some pointers on how to best do this.
Rob.
------------------------------------------------------------------------
diff -U3 -r /home/box/downloads/apr-0.9.4/include/apr_poll.h apr-0.9.4/include/apr_poll.h
--- /home/box/downloads/apr-0.9.4/include/apr_poll.h 2003-03-06 08:22:26.000000000 +1100
+++ apr-0.9.4/include/apr_poll.h 2004-03-05 08:57:56.000000000 +1100
@@ -270,6 +270,14 @@
const apr_pollfd_t *descriptor);
/**
+ * Update the requested events for the descriptor in the underlying implementation
+ * @param pollset The pollset that the descriptor is a member of
+ * @param descriptor The descriptor to update
+ */
+APR_DECLARE(apr_status_t) apr_pollset_update(apr_pollset_t *pollset,
+ const apr_pollfd_t *descriptor);
+
+/**
* Block for activity on the descriptor(s) in a pollset
* @param pollset The pollset to use
* @param timeout Timeout in microseconds
diff -U3 -r /home/box/downloads/apr-0.9.4/poll/unix/poll.c apr-0.9.4/poll/unix/poll.c
--- /home/box/downloads/apr-0.9.4/poll/unix/poll.c 2003-01-07 11:52:56.000000000 +1100
+++ apr-0.9.4/poll/unix/poll.c 2004-03-05 09:26:54.000000000 +1100
@@ -515,6 +515,55 @@
return APR_NOTFOUND;
}
+APR_DECLARE(apr_status_t) apr_pollset_update(apr_pollset_t *pollset,
+ const apr_pollfd_t *descriptor)
+{
+ apr_uint32_t i;
+
+#ifndef HAVE_POLL
+ apr_os_sock_t fd;
+
+ if (descriptor->desc_type == APR_POLL_SOCKET) {
+ fd = descriptor->desc.s->socketdes;
+ }
+ else {
+#if !APR_FILES_AS_SOCKETS
+ return APR_EBADF;
+#else
+ fd = descriptor->desc.f->filedes;
+#endif
+ }
+#endif /* !HAVE_POLL */
+
+ for (i = 0; i < pollset->nelts; i++) {
+ if (descriptor->desc.s == pollset->query_set[i].desc.s) {
+ /* Found an instance of the fd: update its events */
+ pollset->query_set[i].reqevents = descriptor->reqevents;
+
+#ifdef HAVE_POLL
+ pollset->pollset[i].events = get_event(descriptor->reqevents);
+#else
+ if (descriptor->reqevents & APR_POLLIN) {
+ FD_SET(fd, &(pollset->readset));
+ }
+ if (descriptor->reqevents & APR_POLLOUT) {
+ FD_SET(fd, &(pollset->writeset));
+ }
+ if (descriptor->reqevents &
+ (APR_POLLPRI | APR_POLLERR | APR_POLLHUP | APR_POLLNVAL)) {
+ FD_SET(fd, &(pollset->exceptset));
+ }
+#endif
+ }
+ }
+ + if (i == pollset->nelts) {
+ return APR_NOTFOUND;
+ }
+
+ return APR_SUCCESS;
+}
+
#ifdef HAVE_POLL
APR_DECLARE(apr_status_t) apr_pollset_poll(apr_pollset_t *pollset,
apr_interval_time_t timeout,
