Add minimal WebSocket server implementation for evhttp (#1322)

This adds few functions to use evhttp-based webserver to handle incoming
WebSockets connections. We've tried to use both libevent and libwebsockets in
our application, but found that we need to have different ports at the same
time to handle standard HTTP and WebSockets traffic. This change can help to
stick only with libevent library.

Implementation was inspired by modified Libevent source code in ipush project
[1].

  [1]: https://github.com/sqfasd/ipush/tree/master/deps/libevent-2.0.21-stable

Also, WebSocket-based chat server was added as a sample.

1 files changed, 10 insertions, 0 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 100d7703..8ada925c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -820,6 +820,7 @@ set(HDR_PRIVATE
     util-internal.h
     openssl-compat.h
     evconfig-private.h
+    sha1.h
     compat/sys/queue.h)
 
 set(HDR_COMPAT
@@ -854,6 +855,7 @@ set(HDR_PUBLIC
     include/event2/tag_compat.h
     include/event2/thread.h
     include/event2/util.h
+    include/event2/ws.h
     include/event2/visibility.h
     ${PROJECT_BINARY_DIR}/include/event2/event-config.h)
 
@@ -966,8 +968,12 @@ set(SRC_EXTRA
     event_tagging.c
     http.c
     evdns.c
+    ws.c
+    sha1.c
     evrpc.c)
 
+set_source_files_properties(sha1.c PROPERTIES COMPILE_FLAGS
+    -D${CMAKE_C_BYTE_ORDER}=1)
 add_definitions(-DHAVE_CONFIG_H)
 
 # We use BEFORE here so we don't accidentally look in system directories
@@ -1134,6 +1140,7 @@ if (NOT EVENT__DISABLE_SAMPLES)
 
     set(SAMPLES_WOPT
         dns-example
+        ws-chat-server
         http-server
     )
     foreach (SAMPLE ${SAMPLES_WOPT})
@@ -1217,6 +1224,7 @@ if (NOT EVENT__DISABLE_TESTS)
                  test/regress_et.c
                  test/regress_finalize.c
                  test/regress_http.c
+                 test/regress_http.h
                  test/regress_listener.c
                  test/regress_main.c
                  test/regress_minheap.c
@@ -1225,6 +1233,8 @@ if (NOT EVENT__DISABLE_TESTS)
                  test/regress_testutils.h
                  test/regress_util.c
                  test/regress_watch.c
+                 test/regress_ws.c
+                 test/regress_ws.h
                  test/tinytest.c)
 
             if (WIN32)