Add wepoll support to light up the epoll backend on Windows

libevent is lacking a scalable backend on Windows. Let's leverage the wepoll
library until Windows comes up with an epoll/kqueue compete user mode API.

- All regress tests pass for standard wepoll
- These 2 tests fail intermittently for changelist wepoll, so disabling
  changelist wepoll for now
     http/cancel_inactive_server
     http/stream_in
- verify target on Windows runs tests for both wepoll and win32 backends
- wepoll backend preferred over win32 backend
- wepoll version 1.5.6

v2: cleaner backend abstraction. Disallow wepoll on MinGW/Cygwin.
v3: Add wepoll.h to dist
v4: Make sure wepoll source files are excluded from cygwin/mingw builds
v5: Keep win32 as default backend on windows.
v6: Include wepoll in mingw builds. Verified that regress tests pass w/ WEPOLL backend.
v7: Enable wepoll on mingw when building with cmake
v8: Add wepoll testrunner for autotools test target

1 files changed, 6 insertions, 0 deletions

diff --git a/event.c b/event.c
index 29a2c6d5..66e27129 100644
--- a/event.c
+++ b/event.c
@@ -96,6 +96,9 @@ extern const struct eventop kqops;
 #ifdef EVENT__HAVE_DEVPOLL
 extern const struct eventop devpollops;
 #endif
+#ifdef EVENT__HAVE_WEPOLL
+extern const struct eventop wepollops;
+#endif
 #ifdef _WIN32
 extern const struct eventop win32ops;
 #endif
@@ -123,6 +126,9 @@ static const struct eventop *eventops[] = {
 #ifdef _WIN32
 	&win32ops,
 #endif
+#ifdef EVENT__HAVE_WEPOLL
+	&wepollops,
+#endif
 	NULL
 };