Add tradcpp to the repository, and use it as GENCPP (generic preprocessor)

With lots of experimenting, tradcpp (0.4) seems to work way better
than gcc, and it's output is actually valid. We'll go with that for
now.

cde/util/tradcpp/tests/tradcpp.sh

@@ -0,0 +1,36 @@
+test_case() {
+	local name="$1"
+	local source="$2"
+	local tradcpp="$3"
+	local descr="Test tradcpp behavior"
+	atf_test_case ${name}
+	if [ -e "$(atf_get_srcdir)/${name}.txt" ]; then
+		descr=$(cat "$(atf_get_srcdir)/${name}.txt")
+	fi
+	eval "${name}_head() { \
+		atf_set descr \"${descr}\"; \
+		atf_set require.progs \"/usr/bin/tradcpp\"; \
+	}"
+	local stdout="file:$(atf_get_srcdir)/${name}.good"
+	local options=""
+	local options_file="$(atf_get_srcdir)/${name}.cmdline"
+	if [ -e ${options_file} ]; then
+		options=$(cat ${options_file})
+	fi
+	eval "${name}_body() { \
+		atf_check -s eq:0 -o ${stdout} -x '${tradcpp} ${options} ${source} 2>&1 || echo FAILED'; \
+	}"
+}
+
+atf_init_test_cases() {
+	local tradcpp=$(make -V .OBJDIR -C $(atf_get_srcdir)/..)/tradcpp
+	if [ ! -x ${tradcpp} ]; then
+		tradcpp=/usr/bin/tradcpp
+	fi
+	cd $(atf_get_srcdir)
+	for testfile in t*.c; do
+		local name=${testfile%%.c}
+		test_case ${name} ${testfile} ${tradcpp}
+		atf_add_test_case ${name}
+	done
+}