[Libguestfs] [PATCH nbdkit incomplete 3/5] server: sockets: Refactor accept_incoming_connections.
This is a simple refactoring of the function, allowing us to
reimplement the inner loop for Windows in a future commit. Note that
I made explicit that fds[nr_socks] is used for the quit_fd entry,
previously this was implicit which was somewhat confusing.
---
server/sockets.c | 64 ++++++++++++++++++++++++++++++------------------
1 file changed, 40 insertions(+), 24 deletions(-)
diff --git a/server/sockets.c b/server/sockets.c
index d92236f..cc15c5e 100644
--- a/server/sockets.c
+++ b/server/sockets.c
@@ -314,39 +314,55 @@ accept_connection (int listen_sock)
*/
}
-void
-accept_incoming_connections (int *socks, size_t nr_socks)
+/* Check the list of sockets plus quit_fd until a POLLIN event occurs
+ * on any of them.
+ *
+ * If POLLIN occurs on quit_fd do nothing except returning early
+ * (don't call accept_connection in this case).
+ *
+ * If POLLIN occurs on one of the sockets, call
+ * accept_connection (socks[i]) on each of them.
+ */
+static void
+check_sockets_and_quit_fd (int *socks, size_t nr_socks)
{
struct pollfd fds[nr_socks + 1];
size_t i;
int r;
- while (!quit) {
- for (i = 0; i < nr_socks; ++i) {
- fds[i].fd = socks[i];
- fds[i].events = POLLIN;
- fds[i].revents = 0;
- }
- fds[i].fd = quit_fd;
+ for (i = 0; i < nr_socks; ++i) {
+ fds[i].fd = socks[i];
fds[i].events = POLLIN;
fds[i].revents = 0;
+ }
+ fds[nr_socks].fd = quit_fd;
+ fds[nr_socks].events = POLLIN;
+ fds[nr_socks].revents = 0;
- r = poll (fds, nr_socks + 1, -1);
- if (r == -1) {
- if (errno == EINTR || errno == EAGAIN)
- continue;
- perror ("poll");
- exit (EXIT_FAILURE);
- }
+ r = poll (fds, nr_socks + 1, -1);
+ if (r == -1) {
+ if (errno == EINTR || errno == EAGAIN)
+ return;
+ perror ("poll");
+ exit (EXIT_FAILURE);
+ }
- /* We don't even have to read quit_fd - just knowing that it has data
- * means the signal handler ran, so we are ready to quit the loop. */
+ /* We don't even have to read quit_fd - just knowing that it has
+ * data means the signal handler ran, so we are ready to quit the
+ * loop.
+ */
+ if (fds[nr_socks].revents & POLLIN)
+ return;
+
+ for (i = 0; i < nr_socks; ++i) {
if (fds[i].revents & POLLIN)
- continue;
-
- for (i = 0; i < nr_socks; ++i) {
- if (fds[i].revents & POLLIN)
- accept_connection (fds[i].fd);
- }
+ accept_connection (socks[i]);
}
}
+
+void
+accept_incoming_connections (int *socks, size_t nr_socks)
+{
+ while (!quit)
+ check_sockets_and_quit_fd (socks, nr_socks);
+}
--
2.20.1