From a0865a8677b7f64095fbed479b69825bf253adee Mon Sep 17 00:00:00 2001
From: Bert Belder <bertbelder@gmail.com>
Date: Sun, 3 Dec 2017 18:17:01 +0100
Subject: [PATCH] test: add test for automatic dropping or closed sockets

---
 test/test-auto-drop-on-close.c | 107 +++++++++++++++++++++++++++++++++
 1 file changed, 107 insertions(+)
 create mode 100644 test/test-auto-drop-on-close.c

diff --git a/test/test-auto-drop-on-close.c b/test/test-auto-drop-on-close.c
new file mode 100644
index 0000000..a43ce82
--- /dev/null
+++ b/test/test-auto-drop-on-close.c
@@ -0,0 +1,107 @@
+/* This test verifies that sockets are automatically dropped from an epoll set
+ * when they are closed.
+ *
+ * On Linux, a socket would be dropped from the epoll set immediately after the
+ * call to close(). However on Windows, this isn't possible - wepoll may not
+ * detect that a socket has been closed until a call to epoll_wait() is made.
+ *
+ * There are multiple code paths that detect a closed socket in the wepoll
+ * implementation; this test attempts to stress all of them.
+ */
+
+#include <errno.h>
+#include <stdlib.h>
+
+#include "test-util.h"
+#include "util.h"
+#include "wepoll.h"
+#include "win.h"
+
+#include <WS2tcpip.h>
+
+static SOCKET create_and_add_socket(HANDLE ephnd, int events) {
+  SOCKET sock;
+  struct epoll_event ev;
+  int r;
+
+  /* Create UDP socket. */
+  sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+  check(sock != INVALID_SOCKET);
+
+  /* Associate with epoll port. */
+  ev.events = (uint32_t) events;
+  ev.data.sock = sock;
+  r = epoll_ctl(ephnd, EPOLL_CTL_ADD, sock, &ev);
+  check(r == 0);
+
+  return sock;
+}
+
+static void check_dropped(HANDLE ephnd, SOCKET sock) {
+  struct epoll_event ev;
+  int r;
+
+  ev.events = EPOLLERR | EPOLLHUP;
+  ev.data.u64 = 0;
+
+  /* Check that EPOLL_CTL_MOD fails. */
+  r = epoll_ctl(ephnd, EPOLL_CTL_MOD, sock, &ev);
+  check(r < 0);
+  check(errno == ENOENT); /* TODO: should be EBADF. */
+
+  /* Check that EPOLL_CTL_DEL fails. */
+  r = epoll_ctl(ephnd, EPOLL_CTL_DEL, sock, &ev);
+  check(r < 0);
+  check(errno == ENOENT); /* TODO: should be EBADF. */
+}
+
+int main(void) {
+  HANDLE ephnd;
+  SOCKET sock1, sock2, sock3, sock4, sock5;
+  struct epoll_event evs[8];
+  int r;
+
+  ephnd = epoll_create1(0);
+  check(ephnd != INVALID_HANDLE_VALUE);
+
+  sock1 = create_and_add_socket(ephnd, EPOLLIN);
+  sock2 = create_and_add_socket(ephnd, EPOLLIN);
+  sock3 = create_and_add_socket(ephnd, EPOLLOUT);
+  sock4 = create_and_add_socket(ephnd, EPOLLOUT | EPOLLONESHOT);
+  sock5 = create_and_add_socket(ephnd, 0);
+
+  r = closesocket(sock1);
+  check(r == 0);
+
+  r = epoll_wait(ephnd, evs, array_count(evs), -1);
+  check(r == 2); /* sock3 and sock4 should report events. */
+
+  check_dropped(ephnd, sock1);
+
+  r = closesocket(sock2);
+  check(r == 0);
+  r = closesocket(sock3);
+  check(r == 0);
+
+  r = epoll_wait(ephnd, evs, array_count(evs), 0);
+  check(r == 0); /* No events should be reported. */
+
+  check_dropped(ephnd, sock2);
+  check_dropped(ephnd, sock3);
+
+  r = closesocket(sock4);
+  check(r == 0);
+  r = closesocket(sock5);
+  check(r == 0);
+
+  r = epoll_wait(ephnd, evs, array_count(evs), 0);
+  check(r == 0); /* No events should be reported. */
+
+  check_dropped(ephnd, sock4);
+  check_dropped(ephnd, sock5);
+
+  r = epoll_close(ephnd);
+  check(r == 0);
+
+  return 0;
+}