Permalink
Browse files

linux_udev: Retry poll() on EINTR

The poll() syscall may temporarily fail when it is interrupted by a
signal; -1 is returned and errno is set to EINTR.

When this occurred, the udev event thread exited.

Instead, since this is a temporary failure, just try the call again.
<https://www.gnu.org/software/libc/manual/html_node/Interrupted-Primitives.html>

Signed-off-by: Romain Vimont <rom@rom1v.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
  • Loading branch information...
rom1v authored and jwrdegoede committed Oct 11, 2016
1 parent 09e75e9 commit 0a02d1212bfb7ff2e9f3fc603655b0220b7d6889
Showing with 6 additions and 2 deletions.
  1. +5 −1 libusb/os/linux_udev.c
  2. +1 −1 libusb/version_nano.h
@@ -172,7 +172,11 @@ static void *linux_udev_event_thread_main(void *arg)
usbi_dbg("udev event thread entering.");
while (poll(fds, 2, -1) >= 0) {
while ((r = poll(fds, 2, -1)) >= 0 || errno == EINTR) {
if (r < 0) {
/* temporary failure */
continue;
}
if (fds[0].revents & POLLIN) {
/* activity on control pipe, read the byte and exit */
r = usbi_read(udev_control_pipe[0], &dummy, sizeof(dummy));
@@ -1 +1 @@
#define LIBUSB_NANO 11156
#define LIBUSB_NANO 11157

0 comments on commit 0a02d12

Please sign in to comment.