bugfix: sslhandshake read error details on immediate FFI_ERROR

With the C side now returning FFI_ERROR instead of FFI_OK when
u->error_ret is set after an immediate handshake, the early FFI_OK
path is removed.  Added get_sslhandshake_result() in the FFI_ERROR
branch so errmsg and openssl_error_code are populated when the
error comes from the first call rather than from an async resume.

Author: tzssangglass

lib/resty/core/socket.lua

@@ -424,17 +424,11 @@ local function sslhandshake(cosocket, reused_session, server_name, ssl_verify,
         error("no request ctx found", 2)
     end
 
-    if rc == FFI_OK then
-        if reused_session == false then
-            return true
-        end
-
-        rc = C.ngx_http_lua_ffi_socket_tcp_get_sslhandshake_result(r, u,
-                 session_ptr, errmsg, openssl_error_code)
-    end
-
     while true do
         if rc == FFI_ERROR then
+            rc = C.ngx_http_lua_ffi_socket_tcp_get_sslhandshake_result(r, u,
+                     session_ptr, errmsg, openssl_error_code)
+
             if openssl_error_code[0] ~= 0 then
                 return nil, openssl_error_code[0] .. ": " .. ffi_str(errmsg[0])
             end