ENGINE_cleanup \
CRYPTO_cleanup_all_ex_data \
SSL_get_shutdown \
- SSLv2_client_method )
+ SSLv2_client_method \
+ SSL_CTX_set_next_proto_select_cb )
dnl Make an attempt to detect if this is actually yassl's headers and
dnl OpenSSL emulation layer. We still leave everything else believing
#endif
#ifdef USE_NGHTTP2
+
+#if !defined(HAVE_SSL_CTX_SET_NEXT_PROTO_SELECT_CB) || \
+ defined(OPENSSL_NO_NEXTPROTONEG)
+#error http2 builds require OpenSSL with NPN support
+#endif
+
/*
* in is a list of lenght prefixed strings. this function has to select
* the protocol we want to use from the list and write its string into out.