Fix DnsTlsSocket fast shutdown path
Previously, DnsTlsSocket's destructor told the loop thread to
perform a clean shutdown by closing an IPC file descriptor.
However, the IPC file descriptor is now an eventfd, which does
not alert the listening thread when it is closed.
This change uses the eventfd counter's sign bit as an indication
that the destructor is requesting an immediate close.
Test: Includes regression test.
Bug: 123212403
Bug: 124058672
Change-Id: I6edc26bf504cbfbba7d055b1f8e52ac70e02c6e0
diff --git a/resolv/dns_tls_test.cpp b/resolv/dns_tls_test.cpp
index d8626f1..0bcad30 100644
--- a/resolv/dns_tls_test.cpp
+++ b/resolv/dns_tls_test.cpp
@@ -29,6 +29,8 @@
#include "IDnsTlsSocketFactory.h"
#include "IDnsTlsSocketObserver.h"
+#include "dns_responder/dns_tls_frontend.h"
+
#include <chrono>
#include <arpa/inet.h>
#include <android-base/macros.h>
@@ -918,5 +920,44 @@
EXPECT_FALSE(map.recordQuery(makeSlice(QUERY)));
}
+class StubObserver : public IDnsTlsSocketObserver {
+ public:
+ bool closed = false;
+ void onResponse(std::vector<uint8_t>) override {}
+
+ void onClosed() override { closed = true; }
+};
+
+TEST(DnsTlsSocketTest, SlowDestructor) {
+ constexpr char tls_addr[] = "127.0.0.3";
+ constexpr char tls_port[] = "8530"; // High-numbered port so root isn't required.
+ // This test doesn't perform any queries, so the backend address can be invalid.
+ constexpr char backend_addr[] = "192.0.2.1";
+ constexpr char backend_port[] = "1";
+
+ test::DnsTlsFrontend tls(tls_addr, tls_port, backend_addr, backend_port);
+ ASSERT_TRUE(tls.startServer());
+
+ DnsTlsServer server;
+ parseServer(tls_addr, 8530, &server.ss);
+
+ StubObserver observer;
+ ASSERT_FALSE(observer.closed);
+ DnsTlsSessionCache cache;
+ auto socket = std::make_unique<DnsTlsSocket>(server, MARK, &observer, &cache);
+ ASSERT_TRUE(socket->initialize());
+
+ // Test: Time the socket destructor. This should be fast.
+ auto before = std::chrono::steady_clock::now();
+ socket.reset();
+ auto after = std::chrono::steady_clock::now();
+ auto delay = after - before;
+ ALOGV("Shutdown took %lld ns", delay / std::chrono::nanoseconds{1});
+ EXPECT_TRUE(observer.closed);
+ // Shutdown should complete in milliseconds, but if the shutdown signal is lost
+ // it will wait for the timeout, which is expected to take 20seconds.
+ EXPECT_LT(delay, std::chrono::seconds{5});
+}
+
} // end of namespace net
} // end of namespace android