Added a unit test for websocket_client functionality, other small fixes

examples/websocket_client/websocket_client.c

@@ -17,7 +17,7 @@
 #define PORT "8888"
 #define SSL_CERT "./ssl/server.pem"
 
-int websocket_data_handler(struct mg_connection *conn, int flags, char *data, size_t data_len)
+static int websocket_data_handler(struct mg_connection *conn, int flags, char *data, size_t data_len)
 {
     printf("From server: %s\r\n", data);
 

include/civetweb.h

@@ -573,7 +573,20 @@ CIVETWEB_API void mg_cry(struct mg_connection *conn,
 /* utility method to compare two buffers, case incensitive. */
 CIVETWEB_API int mg_strncasecmp(const char *s1, const char *s2, size_t len);
 
-/* Connect to a websocket as a client */
+/* Connect to a websocket as a client 
+   Parameters:
+     host: host to connect to, i.e. "echo.websocket.org" or "192.168.1.1" or "localhost"
+     port: server port
+     use_ssl: make a secure connection to server
+     error_buffer, error_buffer_size: error message placeholder.
+     path: server path you are trying to connect to, i.e. if connection to localhost/app, path should be "/app"
+     origin: value of the Origin HTTP header
+     data_func: callback that should be used when data is received from the server
+
+   Return:
+     On success, valid mg_connection object.
+     On error, NULL. */
+     
 typedef int  (*websocket_data_func)(struct mg_connection *, int bits,
                            char *data, size_t data_len);
 CIVETWEB_API struct mg_connection *mg_client_websocket_connect(const char *host, int port, int use_ssl,

src/civetweb.c

@@ -6615,9 +6615,10 @@ struct mg_connection *mg_client_websocket_connect(const char *host, int port, in
                              "\r\n", path, host, magic, origin);
 
     //Connection object will be null if something goes wrong
-    if(conn == NULL)
+    if(conn == NULL || (strcmp(conn->request_info.uri, "101") != 0))
     {
         DEBUG_TRACE("Websocket client connect error: %s\r\n", error_buffer);
+        if(conn != NULL) { mg_free(conn); conn = NULL; }
         return conn;
     }
 

test/unit_test.c

@@ -525,6 +525,57 @@ static void test_mg_download(int use_ssl) {
     mg_stop(ctx);
 }
 
+static int websocket_data_handler(struct mg_connection *conn, int flags, char *data, size_t data_len)
+{
+    return 1;
+}
+
+static void test_mg_client_websocket_connect(int use_ssl) {
+    struct mg_connection* conn;
+    char ebuf[100];
+    int port = HTTP_PORT;
+
+    if(use_ssl) { port = HTTPS_PORT; }
+
+    //Try to connect to our own server
+    //TODO: These do not work right now
+
+    //Invalid port test
+    /*conn = mg_client_websocket_connect("localhost", 0, use_ssl,
+                             ebuf, sizeof(ebuf),
+                             "/", "http://localhost",websocket_data_handler);
+    ASSERT(conn == NULL);
+
+    //Should succeed, the default civetweb sever should complete the handshake
+    conn = mg_client_websocket_connect("localhost", port, use_ssl,
+                             ebuf, sizeof(ebuf),
+                             "/", "http://localhost",websocket_data_handler);
+    ASSERT(conn != NULL);*/
+
+
+    //Try an external server test
+    port = 80;
+    if(use_ssl) { port = 443; }
+
+    //Not a websocket server path
+    conn = mg_client_websocket_connect("websocket.org", port, use_ssl,
+                             ebuf, sizeof(ebuf),
+                             "/", "http://websocket.org",websocket_data_handler);
+    ASSERT(conn == NULL);
+
+    //Invalid port test
+    conn = mg_client_websocket_connect("echo.websocket.org", 0, use_ssl,
+                             ebuf, sizeof(ebuf),
+                             "/", "http://websocket.org",websocket_data_handler);
+    ASSERT(conn == NULL);
+
+    //Should succeed, echo.websocket.org echos the data back
+    conn = mg_client_websocket_connect("echo.websocket.org", port, use_ssl,
+                             ebuf, sizeof(ebuf),
+                             "/", "http://websocket.org",websocket_data_handler);
+    ASSERT(conn != NULL);
+}
+
 static int alloc_printf(char **buf, size_t size, char *fmt, ...) {
     va_list ap;
     va_start(ap, fmt);
@@ -1016,6 +1067,12 @@ int __cdecl main(void) {
 #ifndef NO_SSL
     test_mg_download(1);
 #endif
+
+    test_mg_client_websocket_connect(0);
+#ifndef NO_SSL
+    test_mg_client_websocket_connect(1);
+#endif
+
     test_mg_upload();
     test_request_replies();
     test_api_calls();