Make valgrind optional

Some platforms don't have valgrind support, and sometimes you simply might
not want to use valgrind.  But at present, dtc, or more specifically its
testsuite, won't compile without valgrind because we use the valgrind
client interface in some places to improve our testing and suppress false
positives.

This adds some Makefile detection to correctly handle the case where
valgrind is not available.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

.travis.yml

@@ -25,11 +25,8 @@ matrix:
         - make
         - make check && make checkm
 
-    # Check it builds properly without the python bits
-    - addons:
-        apt:
-          packages:
-            - valgrind
-      script:
+    # Check it builds properly without optional packages:
+    #     python, valgrind
+    - script:
         - make
         - make check

Makefile

@@ -39,6 +39,13 @@ INCLUDEDIR = $(PREFIX)/include
 HOSTOS := $(shell uname -s | tr '[:upper:]' '[:lower:]' | \
 	    sed -e 's/\(cygwin\|msys\).*/\1/')
 
+NO_VALGRIND := $(shell $(PKG_CONFIG) --exists valgrind; echo $$?)
+ifeq ($(NO_VALGRIND),1)
+	CFLAGS += -DNO_VALGRIND
+else
+	CFLAGS += $(shell $(PKG_CONFIG) --cflags valgrind)
+endif
+
 ifeq ($(HOSTOS),darwin)
 SHAREDLIB_EXT     = dylib
 SHAREDLIB_CFLAGS  = -fPIC

tests/Makefile.tests

@@ -83,8 +83,13 @@ tests_clean:
 check:	tests ${TESTS_BIN} $(TESTS_PYLIBFDT)
 	cd $(TESTS_PREFIX); ./run_tests.sh
 
+ifeq ($(NO_VALGRIND),1)
+checkm:
+	@echo "make checkm requires valgrind, but NO_VALGRIND=1"
+else
 checkm: tests ${TESTS_BIN} $(TESTS_PYLIBFDT)
 	cd $(TESTS_PREFIX); ./run_tests.sh -m 2>&1 | tee vglog.$$$$
+endif
 
 checkv:	tests ${TESTS_BIN} $(TESTS_PYLIBFDT)
 	cd $(TESTS_PREFIX); ./run_tests.sh -v

tests/testutils.c

@@ -30,7 +30,17 @@
 #include <unistd.h>
 #include <fcntl.h>
 
+#if NO_VALGRIND
+static inline void VALGRIND_MAKE_MEM_UNDEFINED(void *p, size_t len)
+{
+}
+
+static inline void VALGRIND_MAKE_MEM_DEFINED(void *p, size_t len)
+{
+}
+#else
 #include <valgrind/memcheck.h>
+#endif
 
 #include <libfdt.h>