backwards compatible api

lib/CMakeLists.txt

@@ -41,6 +41,25 @@ list(APPEND foo_sources
     rtt_measure_impl.cc
 )
 
+set(PACKAGE_FIND_VERSION_MAJOR 0)
+include(GnuradioConfigVersion)
+
+if(${API_COMPAT} EQUAL 8)
+    message(STATUS "next branch (3.8 install), using new API")
+    add_definitions("-DGR_FOO_NEW_API")
+elseif(${MINOR_VERSION} GREATER 7)
+    message(STATUS "recent 3.7.8 install, using new API")
+    add_definitions("-DGR_FOO_NEW_API")
+elseif(${MINOR_VERSION} EQUAL 7 AND NOT ${MAINT_VERSION} STREQUAL "git")
+    message(STATUS "recent real 3.7.7 install, using new API")
+    add_definitions("-DGR_FOO_NEW_API")
+elseif(${MINOR_VERSION} EQUAL 6 AND NOT ${MAINT_VERSION} STREQUAL "git" AND ${MAINT_VERSION} GREATER 0)
+    message(STATUS "3.7.6 with maint version >= 1 install, using new API")
+    add_definitions("-DGR_FOO_NEW_API")
+else()
+    message(STATUS "using old API")
+endif()
+
 add_library(gnuradio-foo SHARED ${foo_sources})
 target_link_libraries(gnuradio-foo ${Boost_LIBRARIES} ${GNURADIO_RUNTIME_LIBRARIES} ${GNURADIO_PMT_LIBRARIES} ${UHD_LIBRARIES})
 set_target_properties(gnuradio-foo PROPERTIES DEFINE_SYMBOL "gnuradio_foo_EXPORTS")

lib/wireshark_connector_impl.cc

@@ -162,7 +162,11 @@ wireshark_connector_impl::general_work(int noutput, gr_vector_int& ninput_items,
 	gr_complex *out = (gr_complex*)output_items[0];
 
 	if(!d_msg_len) {
+#ifdef GR_FOO_NEW_API
 		pmt::pmt_t msg(delete_head_blocking(pmt::mp("in"), 100));
+#else
+		pmt::pmt_t msg(delete_head_blocking(pmt::mp("in")));
+#endif
 
 		if(!msg) {
 			return 0;