libcutils: cleanups for -fsanitize=integer

Hash functions rely on overflow behavior, so whitelist them.

ATRACE_TAG_NOT_READY: use an unsigned constant when shifting bits.
Otherwise, the value overflows on shift. The users of this constant
assign it to a uint64_t variable.

Change-Id: I21c437ce2083525e906c3ead3259ec34a1ef4b66

include/cutils/trace.h

@@ -71,7 +71,7 @@ __BEGIN_DECLS
 #define ATRACE_TAG_LAST             ATRACE_TAG_PACKAGE_MANAGER
 
 // Reserved for initialization.
-#define ATRACE_TAG_NOT_READY        (1LL<<63)
+#define ATRACE_TAG_NOT_READY        (1ULL<<63)
 
 #define ATRACE_TAG_VALID_MASK ((ATRACE_TAG_LAST - 1) | ATRACE_TAG_LAST)
 

libcutils/hashmap.c

@@ -77,6 +77,9 @@ Hashmap* hashmapCreate(size_t initialCapacity,
 /**
  * Hashes the given key.
  */
+#ifdef __clang__
+__attribute__((no_sanitize("integer")))
+#endif
 static inline int hashKey(Hashmap* map, void* key) {
     int h = map->hash(key);
 
@@ -152,6 +155,10 @@ void hashmapFree(Hashmap* map) {
     free(map);
 }
 
+#ifdef __clang__
+__attribute__((no_sanitize("integer")))
+#endif
+/* FIXME: relies on signed integer overflow, which is undefined behavior */
 int hashmapHash(void* key, size_t keySize) {
     int h = keySize;
     char* data = (char*) key;

libcutils/str_parms.c

@@ -42,6 +42,9 @@ static bool str_eq(void *key_a, void *key_b)
 }
 
 /* use djb hash unless we find it inadequate */
+#ifdef __clang__
+__attribute__((no_sanitize("integer")))
+#endif
 static int str_hash_fn(void *str)
 {
     uint32_t hash = 5381;