Remove cmocka submodule, rely on system-wide installation instead.

We used to ship git submodule instructions to build a local copy of
cmocka in vendor/cmocka/ and use that (if cmake is installed) to build
unit tests.  With the network test driver this turns out to be a
LD_LIBRARY_PATH vs. SUDO complication which is really outweighing the
benefit of a local build today - so, use the system-wide installation
if available (querying pgk-config).  Do not build unit-tests otherwise.

v2: (inspired by patch from David Sommerseth)
  introduce "configure --disable-unit-test" switch
  simplify configure.ac logic
  use CMOCKA_LIBS and CMOCKA_INCLUDE (set by PKG_CHECK)

v3:
  repair conflict with commit 7473f32
  CMOCKA_INCLUDE is not correct, must be CMOCKA_CFLAGS (see config.status)

Signed-off-by: Gert Doering <gert@greenie.muc.de>
Acked-by: David Sommerseth <davids@openvpn.net>
Message-Id: <20190623183210.6005-1-gert@greenie.muc.de>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg18570.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>

INSTALL

@@ -156,6 +156,20 @@ Test SSL/TLS negotiations (runs for 2 minutes):
 For more thorough client-server tests you can configure your own, private test
 environment. See tests/t_client.rc-sample for details.
 
+To do the C unit tests, you need to have the "cmocka" test framework
+installed on your system.  More recent distributions already ship this
+as part of their packages/ports.  If your system does not have it,
+you can install cmocka with these commands:
+
+  $ git clone https://git.cryptomilk.org/projects/cmocka.git
+  $ cd cmocka
+  $ mkdir build
+  $ cd build
+  $ cmake -DCMAKE_INSTALL_PREFIX=/usr/local -DCMAKE_BUILD_TYPE=Debug ..
+  $ make
+  $ sudo make install
+
+
 *************************************************************************
 
 OPTIONS for ./configure:

Makefile.am

@@ -53,7 +53,7 @@ BUILT_SOURCES = \
 	config-version.h
 endif
 
-SUBDIRS = build distro include src sample doc vendor tests
+SUBDIRS = build distro include src sample doc tests
 
 dist_doc_DATA = \
 	README \

configure.ac

@@ -1361,33 +1361,32 @@ AC_SUBST([sampledir])
 AC_SUBST([systemdunitdir])
 AC_SUBST([tmpfilesdir])
 
+AC_ARG_ENABLE(
+     [unit-tests],
+     [AS_HELP_STRING([--disable-unit-tests],
+                     [Disables building and running the unit tests suite])],
+     [],
+     [enable_unit_tests="yes"]
+)
+
+# Check if cmocka is available - needed for unit testing
+PKG_CHECK_MODULES(
+	[CMOCKA], [cmocka],
+	[have_cmocka="yes"],
+	[AC_MSG_WARN([cmocka.pc not found on the system.  Unit tests disabled])]
+)
+AM_CONDITIONAL([ENABLE_UNITTESTS], [test "${enable_unit_tests}" = "yes" -a "${have_cmocka}" = "yes" ])
+AC_SUBST([ENABLE_UNITTESTS])
+
 TEST_LDFLAGS="${OPTIONAL_CRYPTO_LIBS} ${OPTIONAL_PKCS11_HELPER_LIBS}"
-TEST_LDFLAGS="${TEST_LDFLAGS} ${OPTIONAL_LZO_LIBS}"
-TEST_LDFLAGS="${TEST_LDFLAGS} -lcmocka -L\$(top_builddir)/vendor/dist/lib"
-TEST_LDFLAGS="${TEST_LDFLAGS} -Wl,-rpath,\$(top_builddir)/vendor/dist/lib"
+TEST_LDFLAGS="${TEST_LDFLAGS} ${OPTIONAL_LZO_LIBS} ${CMOCKA_LIBS}"
 TEST_CFLAGS="${OPTIONAL_CRYPTO_CFLAGS} ${OPTIONAL_PKCS11_HELPER_CFLAGS}"
 TEST_CFLAGS="${TEST_CFLAGS} ${OPTIONAL_LZO_CFLAGS}"
-TEST_CFLAGS="${TEST_CFLAGS} -I\$(top_srcdir)/include -I\$(top_builddir)/vendor/dist/include"
+TEST_CFLAGS="${TEST_CFLAGS} -I\$(top_srcdir)/include ${CMOCKA_CFLAGS}"
 
 AC_SUBST([TEST_LDFLAGS])
 AC_SUBST([TEST_CFLAGS])
 
-# Check if cmake is available and cmocka git submodule is initialized,
-# needed for unit testing
-AC_CHECK_PROGS([CMAKE], [cmake])
-if test -n "${CMAKE}"; then
-   if test -f "${srcdir}/vendor/cmocka/CMakeLists.txt"; then
-      AM_CONDITIONAL([CMOCKA_INITIALIZED], [true])
-   else
-      AM_CONDITIONAL([CMOCKA_INITIALIZED], [false])
-      AC_MSG_RESULT([!! WARNING !! The cmoka git submodule has not been initialized or updated.  Unit testing cannot be performed.])
-   fi
-else
-   AC_MSG_RESULT([!! WARNING !! CMake is NOT available.  Unit testing cannot be performed.])
-   AM_CONDITIONAL([CMOCKA_INITIALIZED], [false])
-fi
-
-
 AC_CONFIG_FILES([
 	version.sh
 	Makefile
@@ -1415,7 +1414,6 @@ AC_CONFIG_FILES([
         tests/unit_tests/openvpn/Makefile
         tests/unit_tests/plugins/Makefile
         tests/unit_tests/plugins/auth-pam/Makefile
-        vendor/Makefile
 	sample/Makefile
 ])
 AC_CONFIG_FILES([tests/t_client.sh], [chmod +x tests/t_client.sh])

tests/unit_tests/Makefile.am

@@ -1,5 +1,5 @@
 AUTOMAKE_OPTIONS = foreign
 
-if CMOCKA_INITIALIZED
+if ENABLE_UNITTESTS
 SUBDIRS = example_test openvpn plugins
 endif