dumptrees: pass outputdir as first argument

Instead of outputing files to current directory, allow to specificy an
output directory. This helps with meson build system out-of-tree support.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20191009102025.10179-4-marcandre.lureau@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

tests/Makefile.tests

@@ -74,7 +74,7 @@ $(TESTS_PREFIX)dumptrees: $(TESTS_PREFIX)trees.o
 
 $(TESTS_TREES): $(TESTS_PREFIX)dumptrees
 	@$(VECHO) DUMPTREES
-	cd $(TESTS_PREFIX); ./dumptrees >/dev/null
+	cd $(TESTS_PREFIX); ./dumptrees . >/dev/null
 
 tests_clean:
 	@$(VECHO) CLEAN "(tests)"

tests/dumptrees.c

@@ -32,6 +32,16 @@ int main(int argc, char *argv[])
 {
 	int i;
 
+	if (argc != 2) {
+	    fprintf(stderr, "Missing output directory argument\n");
+	    return 1;
+	}
+
+	if (chdir(argv[1]) != 0) {
+	    perror("chdir()");
+	    return 1;
+	}
+
 	for (i = 0; i < NUM_TREES; i++) {
 		void *blob = trees[i].blob;
 		const char *filename = trees[i].filename;