Suppress false positive memory leak warnings.
Clang static analyzer does not know the transfer of
object ownership to hashmapPut. Use a fake global
pointer variable to trick the analyzer.
BUG: 26955438
Change-Id: Id3ac595fff14e48d28a1147461cd836914857086
diff --git a/libcutils/str_parms.c b/libcutils/str_parms.c
index 4f23d09..8dafded 100644
--- a/libcutils/str_parms.c
+++ b/libcutils/str_parms.c
@@ -31,6 +31,20 @@
#define UNUSED __attribute__((unused))
+/* When an object is allocated but not freed in a function,
+ * because its ownership is released to other object like a hashmap,
+ * call RELEASE_OWNERSHIP to tell the clang analyzer and avoid
+ * false warnings about potential memory leak.
+ * For now, a "temporary" assignment to global variables
+ * is enough to confuse the clang static analyzer.
+ */
+#ifdef __clang_analyzer__
+static void *released_pointer;
+#define RELEASE_OWNERSHIP(x) { released_pointer = x; released_pointer = 0; }
+#else
+#define RELEASE_OWNERSHIP(x)
+#endif
+
struct str_parms {
Hashmap *map;
};
@@ -170,9 +184,12 @@
/* if we replaced a value, free it */
old_val = hashmapPut(str_parms->map, key, value);
+ RELEASE_OWNERSHIP(value);
if (old_val) {
free(old_val);
free(key);
+ } else {
+ RELEASE_OWNERSHIP(key);
}
items++;
@@ -222,10 +239,13 @@
goto clean_up;
}
// For new keys, hashmap takes ownership of tmp_key and tmp_val.
+ RELEASE_OWNERSHIP(tmp_key);
+ RELEASE_OWNERSHIP(tmp_val);
tmp_key = tmp_val = NULL;
} else {
// For existing keys, hashmap takes ownership of tmp_val.
// (It also gives up ownership of old_val.)
+ RELEASE_OWNERSHIP(tmp_val);
tmp_val = NULL;
}