pollfds_fill() and pollfds_poll() translate GPollFD to rfds/wfds/xfds
for sockets on win32. select(2) is the underlying system call which is
used to monitor sockets for activity.
Currently file descriptors that monitor G_IO_ERR will be included in
both rfds and wfds. As a result, select(2) will report writability on
file descriptors where we only really wanted to monitor readability
(with errors).
slirp_pollfds_poll() hit this issue: UDP sockets are blocking sockets so
we hang in sorecvfrom() when G_IO_ERR is set due to the socket being
writable (we only wanted to check for readability).
This patch fixes the slirp_pollfds_poll() hang.
Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com>
---
main-loop.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/main-loop.c b/main-loop.c
index f46aece..2b8eed7 100644
--- a/main-loop.c
+++ b/main-loop.c
@@ -333,11 +333,11 @@ static int pollfds_fill(GArray *pollfds, fd_set *rfds,
fd_set *wfds,
GPollFD *pfd = &g_array_index(pollfds, GPollFD, i);
int fd = pfd->fd;
int events = pfd->events;
- if (events & (G_IO_IN | G_IO_HUP | G_IO_ERR)) {
+ if (events & G_IO_IN) {
FD_SET(fd, rfds);
nfds = MAX(nfds, fd);
}
- if (events & (G_IO_OUT | G_IO_ERR)) {
+ if (events & G_IO_OUT) {
FD_SET(fd, wfds);
nfds = MAX(nfds, fd);
}
@@ -360,10 +360,10 @@ static void pollfds_poll(GArray *pollfds, int nfds,
fd_set *rfds,
int revents = 0;
if (FD_ISSET(fd, rfds)) {
- revents |= G_IO_IN | G_IO_HUP | G_IO_ERR;
+ revents |= G_IO_IN;
}
if (FD_ISSET(fd, wfds)) {
- revents |= G_IO_OUT | G_IO_ERR;
+ revents |= G_IO_OUT;
}
if (FD_ISSET(fd, xfds)) {
revents |= G_IO_PRI;
--
1.8.1.4
