Merge "Fix asynchronous DNS API flag NO_CACHE_LOOKUP behavior" (54fd7454) · Commits · e / os / android_packages_modules_DnsResolver

res_cache.cpp

+6 −3

Original line number	Original line	Diff line number	Diff line
	@@ -1411,8 +1411,10 @@ static resolv_cache_info* find_cache_info_locked(unsigned netid) REQUIRES(cache_
	ResolvCacheStatus _resolv_cache_lookup(unsigned netid, const void* query, int querylen,		ResolvCacheStatus _resolv_cache_lookup(unsigned netid, const void* query, int querylen,
	void* answer, int answersize, int* answerlen,		void* answer, int answersize, int* answerlen,
	uint32_t flags) {		uint32_t flags) {
			// Skip cache lookup, return RESOLV_CACHE_NOTFOUND directly so that it is
			// possible to cache the answer of this query.
	if (flags & ANDROID_RESOLV_NO_CACHE_LOOKUP) {		if (flags & ANDROID_RESOLV_NO_CACHE_LOOKUP) {
	return RESOLV_CACHE_SKIP;		return RESOLV_CACHE_NOTFOUND;
	}		}
	Entry key;		Entry key;
	Entry** lookup;		Entry** lookup;
	@@ -1542,7 +1544,8 @@ void _resolv_cache_add(unsigned netid, const void* query, int querylen, const vo
	lookup = _cache_lookup_p(cache, key);		lookup = _cache_lookup_p(cache, key);
	e = *lookup;		e = *lookup;

	if (e != NULL) { /* should not happen */		// Should only happen on ANDROID_RESOLV_NO_CACHE_LOOKUP
			if (e != NULL) {
	LOG(INFO) << __func__ << ": ALREADY IN CACHE (" << e << ") ? IGNORING ADD";		LOG(INFO) << __func__ << ": ALREADY IN CACHE (" << e << ") ? IGNORING ADD";
	_cache_notify_waiting_tid_locked(cache, key);		_cache_notify_waiting_tid_locked(cache, key);
	return;		return;
	@@ -1553,7 +1556,7 @@ void _resolv_cache_add(unsigned netid, const void* query, int querylen, const vo
	if (cache->num_entries >= cache->max_entries) {		if (cache->num_entries >= cache->max_entries) {
	_cache_remove_oldest(cache);		_cache_remove_oldest(cache);
	}		}
	/* need to lookup again */		// TODO: It looks useless, remove below code after having test to prove it.
	lookup = _cache_lookup_p(cache, key);		lookup = _cache_lookup_p(cache, key);
	e = *lookup;		e = *lookup;
	if (e != NULL) {		if (e != NULL) {

resolver_test.cpp

+30 −0

Original line number	Original line	Diff line number	Diff line
	@@ -2116,6 +2116,36 @@ TEST_F(ResolverTest, Async_CacheFlags) {

	// Cache hits, expect still 6 queries		// Cache hits, expect still 6 queries
	EXPECT_EQ(6U, GetNumQueries(dns, host_name));		EXPECT_EQ(6U, GetNumQueries(dns, host_name));

			// Start to verify if ANDROID_RESOLV_NO_CACHE_LOOKUP does write response into cache
			dns.clearQueries();

			fd1 = resNetworkQuery(TEST_NETID, "howdy.example.com", ns_c_in, ns_t_aaaa,
			ANDROID_RESOLV_NO_CACHE_LOOKUP);
			fd2 = resNetworkQuery(TEST_NETID, "howdy.example.com", ns_c_in, ns_t_aaaa,
			ANDROID_RESOLV_NO_CACHE_LOOKUP);

			EXPECT_TRUE(fd1 != -1);
			EXPECT_TRUE(fd2 != -1);

			expectAnswersValid(fd2, AF_INET6, "::1.2.3.4");
			expectAnswersValid(fd1, AF_INET6, "::1.2.3.4");

			// Skip cache, expect 2 queries
			EXPECT_EQ(2U, GetNumQueries(dns, host_name));

			// Re-query without flags
			fd1 = resNetworkQuery(TEST_NETID, "howdy.example.com", ns_c_in, ns_t_aaaa, 0);
			fd2 = resNetworkQuery(TEST_NETID, "howdy.example.com", ns_c_in, ns_t_aaaa, 0);

			EXPECT_TRUE(fd1 != -1);
			EXPECT_TRUE(fd2 != -1);

			expectAnswersValid(fd2, AF_INET6, "::1.2.3.4");
			expectAnswersValid(fd1, AF_INET6, "::1.2.3.4");

			// Cache hits, expect still 2 queries
			EXPECT_EQ(2U, GetNumQueries(dns, host_name));
	}		}

	TEST_F(ResolverTest, Async_NoRetryFlag) {		TEST_F(ResolverTest, Async_NoRetryFlag) {