use result_t, move raw logging and dumping to Port and avoid permanent open/close on ofstream

src/lib/ebus/test/Makefile.am

@@ -1,7 +1,8 @@
 AM_CXXFLAGS = -fpic \
 	      -Wall \
 	      -Wextra \
-	      -I$(top_srcdir)/src/lib/ebus
+	      -I$(top_srcdir)/src/lib/ebus \
+	      -I$(top_srcdir)/src/lib/utils
 
 noinst_PROGRAMS = test_port \
 		  test_symbol \
@@ -9,7 +10,8 @@ noinst_PROGRAMS = test_port \
 		  test_message
 
 test_port_SOURCES = test_port.cpp
-test_port_LDADD = $(top_srcdir)/src/lib/ebus/libebus.a
+test_port_LDADD = $(top_srcdir)/src/lib/utils/libutils.a \
+		  $(top_srcdir)/src/lib/ebus/libebus.a
 
 test_symbol_SOURCES = test_symbol.cpp
 test_symbol_LDADD = $(top_srcdir)/src/lib/ebus/libebus.a