Update from https://crrev.com/327068

sandbox/linux/services/syscall_wrappers_unittest.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "sandbox/linux/services/syscall_wrappers.h"
 
 #include <sys/syscall.h>
 #include <sys/types.h>
 #include <sys/wait.h>
 #include <unistd.h>
+#include <cstring>
 
 #include "base/logging.h"
 #include "base/posix/eintr_wrapper.h"
 #include "base/third_party/valgrind/valgrind.h"
 #include "build/build_config.h"
+#include "sandbox/linux/system_headers/linux_signal.h"
 #include "sandbox/linux/tests/test_utils.h"
 #include "sandbox/linux/tests/unit_tests.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace sandbox {
 
 namespace {
 
 TEST(SyscallWrappers, BasicSyscalls) {
   EXPECT_EQ(getpid(), sys_getpid());
@@ skipping 27 matching lines @@
     _exit(1);
   }
 
   ASSERT_NE(-1, pid);
   int status = 0;
   ASSERT_EQ(pid, HANDLE_EINTR(waitpid(pid, &status, 0)));
   ASSERT_TRUE(WIFEXITED(status));
   EXPECT_EQ(kSuccessExit, WEXITSTATUS(status));
 }
 
+TEST(SyscallWrappers, GetRESUid) {
+  uid_t ruid, euid, suid;
+  uid_t sys_ruid, sys_euid, sys_suid;
+  ASSERT_EQ(0, getresuid(&ruid, &euid, &suid));
+  ASSERT_EQ(0, sys_getresuid(&sys_ruid, &sys_euid, &sys_suid));
+  EXPECT_EQ(ruid, sys_ruid);
+  EXPECT_EQ(euid, sys_euid);
+  EXPECT_EQ(suid, sys_suid);
+}
+
+TEST(SyscallWrappers, GetRESGid) {
+  gid_t rgid, egid, sgid;
+  gid_t sys_rgid, sys_egid, sys_sgid;
+  ASSERT_EQ(0, getresgid(&rgid, &egid, &sgid));
+  ASSERT_EQ(0, sys_getresgid(&sys_rgid, &sys_egid, &sys_sgid));
+  EXPECT_EQ(rgid, sys_rgid);
+  EXPECT_EQ(egid, sys_egid);
+  EXPECT_EQ(sgid, sys_sgid);
+}
+
+TEST(SyscallWrappers, LinuxSigSet) {
+  sigset_t sigset;
+  ASSERT_EQ(0, sigemptyset(&sigset));
+  ASSERT_EQ(0, sigaddset(&sigset, LINUX_SIGSEGV));
+  ASSERT_EQ(0, sigaddset(&sigset, LINUX_SIGBUS));
+  uint64_t linux_sigset = 0;
+  std::memcpy(&linux_sigset, &sigset,
+              std::min(sizeof(sigset), sizeof(linux_sigset)));
+  EXPECT_EQ((1ULL << (LINUX_SIGSEGV - 1)) | (1ULL << (LINUX_SIGBUS - 1)),
+            linux_sigset);
+}
+
 }  // namespace
 
 }  // namespace sandbox