Propose and implement unit test framework

Enable use of GoogleTest and created a sample unit test case.

Change-Id: Ie370745a32777d4ed81ee24145364029c8e7bf02
Signed-off-by: Matthew Barth <msbarth@us.ibm.com>
diff --git a/configure.ac b/configure.ac
index 8e1b587..2d4f822 100644
--- a/configure.ac
+++ b/configure.ac
@@ -3,10 +3,10 @@
 AC_INIT([phosphor-host-ipmid], [1.0], [https://github.com/openbmc/phosphor-host-ipmid/issues])
 AC_CONFIG_HEADERS([config.h])
 AM_INIT_AUTOMAKE([subdir-objects -Wall -Werror foreign dist-xz])
+AM_SILENT_RULES([yes])
 
 # Checks for programs.
 AC_PROG_CXX
-AX_CXX_COMPILE_STDCXX_14([noext])
 AC_PROG_CC
 AM_PROG_AR
 AC_PROG_INSTALL
@@ -20,10 +20,36 @@
 AC_CHECK_HEADER(systemd/sd-bus.h, ,[AC_MSG_ERROR([Could not find systemd/sd-bus.h...systemd developement package required])])
 
 # Checks for typedefs, structures, and compiler characteristics.
+AX_CXX_COMPILE_STDCXX_14([noext])
+AX_APPEND_COMPILE_FLAGS([-Wall -Werror], [CFLAGS])
+AX_APPEND_COMPILE_FLAGS([-Wall -Werror], [CXXFLAGS])
 
 # Checks for library functions.
 LT_INIT([dlopen disable-static shared])
 LT_LIB_DLLOAD
 
-AC_CONFIG_FILES([Makefile])
+# Check/set gtest specific functions.
+AX_PTHREAD([GTEST_CPPFLAGS="-DGTEST_HAS_PTHREAD=1"],[GTEST_CPPFLAGS="-DGTEST_HAS_PTHREAD=0"])
+AC_SUBST(GTEST_CPPFLAGS)
+
+AC_ARG_ENABLE([oe-sdk],
+    AS_HELP_STRING([--enable-oe-sdk], [Link testcases absolutely against OE SDK so they can be ran within it.])
+)
+AC_ARG_VAR(OECORE_TARGET_SYSROOT,
+    [Path to the OE SDK SYSROOT])
+AS_IF([test "x$enable_oe_sdk" == "xyes"],
+    AS_IF([test "x$OECORE_TARGET_SYSROOT" == "x"],
+          AC_MSG_ERROR([OECORE_TARGET_SYSROOT must be set with --enable-oe-sdk])
+    )
+    AC_MSG_NOTICE([Enabling OE-SDK at $OECORE_TARGET_SYSROOT])
+    [
+        testcase_flags="-Wl,-rpath,\${OECORE_TARGET_SYSROOT}/lib"
+        testcase_flags="${testcase_flags} -Wl,-rpath,\${OECORE_TARGET_SYSROOT}/usr/lib"
+        testcase_flags="${testcase_flags} -Wl,-dynamic-linker,`find \${OECORE_TARGET_SYSROOT}/lib/ld-*.so | sort -r -n | head -n1`"
+    ]
+    AC_SUBST([OESDK_TESTCASE_FLAGS], [$testcase_flags])
+)
+
+# Create configured output
+AC_CONFIG_FILES([Makefile test/Makefile])
 AC_OUTPUT