Disable valgrind in tests by default

Changes tests so that valgrind is enabled only when the environment
variable KVZ_TEST_VALGRIND is set and equal to "1".

.travis.yml

@@ -36,7 +36,7 @@ script:
   - ./autogen.sh
   - ./configure --enable-werror
   - make --jobs=2 V=1
-  - make check VERBOSE=1
+  - make check KVZ_TEST_VALGRIND=1 VERBOSE=1
 
 after_script:
   # Disable errors to work around Travis not knowing how to fix their stuff.

tests/util.sh

@@ -34,9 +34,18 @@ valgrind_test() {
 
     prepare "${dimensions}" "${frames}"
 
+    # If $KVZ_TEST_VALGRIND is defined and equal to "1", run the test with
+    # valgrind. Otherwise, run without valgrind.
+    if [ "${KVZ_TEST_VALGRIND:-0}" = '1' ]; then
+        valgrind='valgrind --leak-check=full --error-exitcode=1 --'
+    else
+        valgrind=''
+    fi
+
+    # No quotes for $valgrind because it expands to multiple (or zero)
+    # arguments.
     print_and_run \
-        libtool execute \
-            valgrind --leak-check=full --error-exitcode=1 -- \
+        libtool execute $valgrind \
             ../src/kvazaar -i "${yuvfile}" "--input-res=${dimensions}" -o "${hevcfile}" "$@"
 
     print_and_run \