add default enum constants (#521)

CMakeLists.txt

@@ -119,6 +119,7 @@ function(configure_cargo_toml cargo_toml_dir CARGO_PROJECT_VERSION CARGO_LIB_NAM
 		file(COPY
 			${CMAKE_CURRENT_SOURCE_DIR}/include/zenoh.h
 			${CMAKE_CURRENT_SOURCE_DIR}/include/zenoh_memory.h
+			${CMAKE_CURRENT_SOURCE_DIR}/include/zenoh_constants.h
 			DESTINATION ${cargo_toml_dir}/include/)
 	endif()	
 	configure_file("${CMAKE_CURRENT_SOURCE_DIR}/Cargo.toml.in" "${cargo_toml_dir}/Cargo.toml" @ONLY)

include/zenoh.h

@@ -33,6 +33,7 @@ extern "C" {
 #include "zenoh_concrete.h"
 #include "zenoh_opaque.h"
 #include "zenoh_commons.h"
+#include "zenoh_constants.h"
 // clang-format on
 
 #ifdef __cplusplus

include/zenoh_constants.h

@@ -0,0 +1,20 @@
+//
+// Copyright (c) 2022 ZettaScale Technology
+//
+// This program and the accompanying materials are made available under the
+// terms of the Eclipse Public License 2.0 which is available at
+// http://www.eclipse.org/legal/epl-2.0, or the Apache License, Version 2.0
+// which is available at https://www.apache.org/licenses/LICENSE-2.0.
+//
+// SPDX-License-Identifier: EPL-2.0 OR Apache-2.0
+//
+// Contributors:
+//   ZettaScale Zenoh Team, <zenoh@zettascale.tech>
+#pragma once
+
+#define Z_CONGESTION_CONTROL_DEFAULT Z_CONGESTION_CONTROL_BLOCK
+#define Z_CONSOLIDATION_MODE_DEFAULT Z_CONSOLIDATION_MODE_AUTO
+#define Z_PRIORITY_DEFAULT Z_PRIORITY_DATA
+#define Z_QUERY_TARGET_DEFAULT Z_QUERY_TARGET_BEST_MATCHING
+#define Z_RELIABILITY_DEFAULT Z_RELIABILITY_RELIABLE
+#define Z_SAMPLE_KIND_DEFAULT Z_SAMPLE_KIND_PUT