1 files changed, 75 insertions, 0 deletions
diff --git a/test/syscalls/linux/tkill.cc b/test/syscalls/linux/tkill.cc
new file mode 100644
index 000000000..8d8ebbb24
--- /dev/null
+++ b/test/syscalls/linux/tkill.cc
@@ -0,0 +1,75 @@
+// Copyright 2018 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include <cerrno>
+#include <csignal>
+
+#include "gtest/gtest.h"
+#include "test/util/logging.h"
+#include "test/util/test_util.h"
+#include "test/util/thread_util.h"
+
+namespace gvisor {
+namespace testing {
+
+namespace {
+
+static int tkill(pid_t tid, int sig) {
+  int ret;
+  do {
+    // NOTE(b/25434735): tkill(2) could return EAGAIN for RT signals.
+    ret = syscall(SYS_tkill, tid, sig);
+  } while (ret == -1 && errno == EAGAIN);
+  return ret;
+}
+
+TEST(TkillTest, InvalidTID) {
+  EXPECT_THAT(tkill(-1, 0), SyscallFailsWithErrno(EINVAL));
+  EXPECT_THAT(tkill(0, 0), SyscallFailsWithErrno(EINVAL));
+}
+
+TEST(TkillTest, ValidTID) {
+  EXPECT_THAT(tkill(gettid(), 0), SyscallSucceeds());
+}
+
+void SigHandler(int sig, siginfo_t* info, void* context) {
+  TEST_CHECK(sig == SIGRTMAX);
+  TEST_CHECK(info->si_pid == getpid());
+  TEST_CHECK(info->si_uid == getuid());
+  TEST_CHECK(info->si_code == SI_TKILL);
+}
+
+// Test with a real signal. Regression test for b/24790092.
+TEST(TkillTest, ValidTIDAndRealSignal) {
+  struct sigaction sa;
+  sa.sa_sigaction = SigHandler;
+  sigfillset(&sa.sa_mask);
+  sa.sa_flags = SA_SIGINFO;
+  ASSERT_THAT(sigaction(SIGRTMAX, &sa, nullptr), SyscallSucceeds());
+  // InitGoogle blocks all RT signals, so we need undo it.
+  sigset_t unblock;
+  sigemptyset(&unblock);
+  sigaddset(&unblock, SIGRTMAX);
+  ASSERT_THAT(sigprocmask(SIG_UNBLOCK, &unblock, nullptr), SyscallSucceeds());
+  EXPECT_THAT(tkill(gettid(), SIGRTMAX), SyscallSucceeds());
+}
+
+}  // namespace
+
+}  // namespace testing
+}  // namespace gvisor