Fix memory leak and inconsistent output (due to varying fd numbers) in test_util_file.

tests/test_util_file.c

@@ -49,6 +49,7 @@ static void test_write_to_file()
 	       (rv == 0) ? "OK" : "FAIL", outfile2, rv);
 	if (rv == 0)
 		stat_and_cat(outfile2);
+	json_object_put(jso);
 }
 
 static void stat_and_cat(const char *file)
@@ -163,11 +164,18 @@ static void test_read_closed()
 	int d = open("/dev/null", O_RDONLY, 0);
 	if(d < 0)
 	{
-	  puts("FAIL: unable to open");
+		puts("FAIL: unable to open");
+	}
+	// Copy over to a fixed fd number so test output is consistent.
+	int fixed_d = 10;
+	if (dup2(d, fixed_d) < 0)
+	{
+		printf("FAIL: unable to dup to fd %d", fixed_d);
 	}
 	close(d);
+	close(fixed_d);
 
-	json_object *jso = json_object_from_fd(d);
+	json_object *jso = json_object_from_fd(fixed_d);
 	if (jso != NULL)
 	{
 		printf("FAIL: read from closed fd returning non-NULL: 0x%lx\n",

tests/test_util_file.expected

@@ -1,7 +1,7 @@
 OK: json_object_from_fd(./valid.json)={ "foo": 123 }
 OK: json_object_from_file(./not_present.json) correctly returned NULL: json_object_from_file: error opening file ./not_present.json: ERRNO=ENOENT
 
-OK: json_object_from_fd(closed_fd), expecting NULL, EBADF, got:0x0, json_object_from_fd: error reading fd 3: ERRNO=EBADF
+OK: json_object_from_fd(closed_fd), expecting NULL, EBADF, got:0x0, json_object_from_fd: error reading fd 10: ERRNO=EBADF
 
 OK: json_object_to_file(json.out, jso)=0
 file[json.out], size=336, contents={"foo":1234,"foo1":"abcdefghijklmnopqrstuvwxyz","foo2":"abcdefghijklmnopqrstuvwxyz","foo3":"abcdefghijklmnopqrstuvwxyz","foo4":"abcdefghijklmnopqrstuvwxyz","foo5":"abcdefghijklmnopqrstuvwxyz","foo6":"abcdefghijklmnopqrstuvwxyz","foo7":"abcdefghijklmnopqrstuvwxyz","foo8":"abcdefghijklmnopqrstuvwxyz","foo9":"abcdefghijklmnopqrstuvwxyz"}