New CMAKE option NNG_ENABLE_COMPAT (defaults ON)

This option allows the compatibility code to be elided from the build.
This saves build time, and eliminates bloat from a static library when
used strictly in native NNG mode.

CMakeLists.txt

@@ -96,6 +96,9 @@ target_compile_definitions(nng_private INTERFACE NNG_PRIVATE)
 if (NNG_ELIDE_DEPRECATED)
     target_compile_definitions(nng PRIVATE NNG_ELIDE_DEPRECATED)
 endif()
+if (NNG_ENABLE_COMPAT)
+    target_compile_definitions(nng PRIVATE NNG_ENABLE_COMPAT)
+endif()
 
 
 # We can use rlimit to configure the stack size for systems

cmake/NNGOptions.cmake

@@ -39,6 +39,11 @@ option(NNG_ENABLE_COVERAGE "Enable coverage reporting." OFF)
 # for the public library.
 option(NNG_ELIDE_DEPRECATED "Elide deprecated functionality." OFF)
 
+# Turning off the compatibility layer can save some space, and
+# compilation time, but may break legacy applications  It should
+# be left enabled when building a shared library.
+option(NNG_ENABLE_COMPAT "Enable legacy nanomsg API." ON)
+
 option(NNG_ENABLE_STATS "Enable statistics." ON)
 mark_as_advanced(NNG_ENABLE_STATS)
 

src/CMakeLists.txt

@@ -1,5 +1,5 @@
 #
-# Copyright 2021 Staysail Systems, Inc. <[email protected]>
+# Copyright 2024 Staysail Systems, Inc. <[email protected]>
 # Copyright 2018 Capitar IT Group BV <[email protected]>
 #
 # This software is supplied under the terms of the MIT License, a
@@ -16,12 +16,15 @@ target_include_directories(nng_testing PRIVATE ${PROJECT_SOURCE_DIR}/src)
 
 add_subdirectory(core)
 add_subdirectory(platform)
-add_subdirectory(compat)
 add_subdirectory(sp)
 add_subdirectory(supplemental)
 add_subdirectory(tools)
 add_subdirectory(testing)
 
+if (NNG_ENABLE_COMPAT)
+    add_subdirectory(compat)
+endif()
+
 # When building shared libraries we prefer to suppress default symbol
 # visibility, so that only the symbols that should be exposed in the
 # resulting library are.  This is the default with Windows.

src/core/buf_size_test.c

@@ -10,15 +10,17 @@
 
 #include <nuts.h>
 
+#if NNG_ENABLE_COMPAT
 #include <nng/compat/nanomsg/nn.h>
+#endif
 
-	void
+void
 test_buffer_options(void)
 {
 	nng_socket s1;
 	int        val;
 	size_t     sz;
-	char *     opt;
+	char      *opt;
 
 	char *cases[] = {
 		NNG_OPT_RECVBUF,
@@ -62,8 +64,9 @@ test_buffer_options(void)
 void
 test_buffer_legacy(void)
 {
+#if NNG_ENABLE_COMPAT
 	nng_socket s1;
-	char *     opt;
+	char      *opt;
 
 	char *cases[] = {
 		NNG_OPT_RECVBUF,
@@ -104,10 +107,13 @@ test_buffer_legacy(void)
 		NUTS_TRUE(nn_errno() == EINVAL);
 	}
 	NUTS_PASS(nng_close(s1));
+#endif
 }
 
 NUTS_TESTS = {
 	{ "buffer options", test_buffer_options },
+#if NNG_ENABLE_COMPAT
 	{ "buffer legacy", test_buffer_legacy },
+#endif
 	{ NULL, NULL },
 };

tests/CMakeLists.txt

@@ -1,5 +1,5 @@
 #
-#   Copyright 2021 Staysail Systems, Inc. <[email protected]>
+#   Copyright 2024 Staysail Systems, Inc. <[email protected]>
 #   Copyright 2018 Capitar IT Group BV <[email protected]>
 #   Copyright (c) 2012 Martin Sustrik  All rights reserved.
 #   Copyright (c) 2013 GoPivotal, Inc.  All rights reserved.
@@ -155,25 +155,27 @@ add_nng_test(reqstress 60)
 # is because we don't want to make modifications to partially enable some
 # of these tests.  Folks minimizing the library probably don't care too
 # much about these anyway.
-add_nng_compat_test(compat_block 10)
-add_nng_compat_test(compat_bug777 10)
-add_nng_compat_test(compat_bus 10)
-add_nng_compat_test(compat_cmsg 10)
-add_nng_compat_test(compat_msg 10)
-add_nng_compat_test(compat_iovec 10)
-add_nng_compat_test(compat_device 10)
-add_nng_compat_test(compat_pair 10)
-add_nng_compat_test(compat_pipeline 10)
-add_nng_compat_test(compat_poll 10)
-add_nng_compat_test(compat_reqrep 10)
-add_nng_compat_test(compat_survey 10)
-add_nng_compat_test(compat_reqttl 10)
-add_nng_compat_test(compat_shutdown 10)
-add_nng_compat_test(compat_surveyttl 10)
-
-# These are special tests for compat mode, not inherited from the
-# legacy libnanomsg suite.
-add_nng_test(compat_options 5)
+if (NNG_ENABLE_COMPAT)
+    add_nng_compat_test(compat_block 10)
+    add_nng_compat_test(compat_bug777 10)
+    add_nng_compat_test(compat_bus 10)
+    add_nng_compat_test(compat_cmsg 10)
+    add_nng_compat_test(compat_msg 10)
+    add_nng_compat_test(compat_iovec 10)
+    add_nng_compat_test(compat_device 10)
+    add_nng_compat_test(compat_pair 10)
+    add_nng_compat_test(compat_pipeline 10)
+    add_nng_compat_test(compat_poll 10)
+    add_nng_compat_test(compat_reqrep 10)
+    add_nng_compat_test(compat_survey 10)
+    add_nng_compat_test(compat_reqttl 10)
+    add_nng_compat_test(compat_shutdown 10)
+    add_nng_compat_test(compat_surveyttl 10)
+
+    # These are special tests for compat mode, not inherited from the
+    # legacy libnanomsg suite.
+    add_nng_test(compat_options 5)
+endif()
 
 # c++ tests
 add_nng_cpp_test(cplusplus_pair 5)