diff --git a/tests/async_safe_test.cpp b/tests/async_safe_test.cpp
new file mode 100644
index 0000000..3d6fcaa
--- /dev/null
+++ b/tests/async_safe_test.cpp
@@ -0,0 +1,189 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * 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 <gtest/gtest.h>
+
+#if defined(__BIONIC__)
+#include <async_safe/log.h>
+#endif // __BIONIC__
+
+TEST(async_safe_log, smoke) {
+#if defined(__BIONIC__)
+  char buf[BUFSIZ];
+
+  async_safe_format_buffer(buf, sizeof(buf), "a");
+  EXPECT_STREQ("a", buf);
+
+  async_safe_format_buffer(buf, sizeof(buf), "%%");
+  EXPECT_STREQ("%", buf);
+
+  async_safe_format_buffer(buf, sizeof(buf), "01234");
+  EXPECT_STREQ("01234", buf);
+
+  async_safe_format_buffer(buf, sizeof(buf), "a%sb", "01234");
+  EXPECT_STREQ("a01234b", buf);
+
+  char* s = NULL;
+  async_safe_format_buffer(buf, sizeof(buf), "a%sb", s);
+  EXPECT_STREQ("a(null)b", buf);
+
+  async_safe_format_buffer(buf, sizeof(buf), "aa%scc", "bb");
+  EXPECT_STREQ("aabbcc", buf);
+
+  async_safe_format_buffer(buf, sizeof(buf), "a%cc", 'b');
+  EXPECT_STREQ("abc", buf);
+
+  async_safe_format_buffer(buf, sizeof(buf), "a%db", 1234);
+  EXPECT_STREQ("a1234b", buf);
+
+  async_safe_format_buffer(buf, sizeof(buf), "a%db", -8123);
+  EXPECT_STREQ("a-8123b", buf);
+
+  async_safe_format_buffer(buf, sizeof(buf), "a%hdb", static_cast<short>(0x7fff0010));
+  EXPECT_STREQ("a16b", buf);
+
+  async_safe_format_buffer(buf, sizeof(buf), "a%hhdb", static_cast<char>(0x7fffff10));
+  EXPECT_STREQ("a16b", buf);
+
+  async_safe_format_buffer(buf, sizeof(buf), "a%lldb", 0x1000000000LL);
+  EXPECT_STREQ("a68719476736b", buf);
+
+  async_safe_format_buffer(buf, sizeof(buf), "a%ldb", 70000L);
+  EXPECT_STREQ("a70000b", buf);
+
+  async_safe_format_buffer(buf, sizeof(buf), "a%pb", reinterpret_cast<void*>(0xb0001234));
+  EXPECT_STREQ("a0xb0001234b", buf);
+
+  async_safe_format_buffer(buf, sizeof(buf), "a%xz", 0x12ab);
+  EXPECT_STREQ("a12abz", buf);
+
+  async_safe_format_buffer(buf, sizeof(buf), "a%Xz", 0x12ab);
+  EXPECT_STREQ("a12ABz", buf);
+
+  async_safe_format_buffer(buf, sizeof(buf), "a%08xz", 0x123456);
+  EXPECT_STREQ("a00123456z", buf);
+
+  async_safe_format_buffer(buf, sizeof(buf), "a%5dz", 1234);
+  EXPECT_STREQ("a 1234z", buf);
+
+  async_safe_format_buffer(buf, sizeof(buf), "a%05dz", 1234);
+  EXPECT_STREQ("a01234z", buf);
+
+  async_safe_format_buffer(buf, sizeof(buf), "a%8dz", 1234);
+  EXPECT_STREQ("a    1234z", buf);
+
+  async_safe_format_buffer(buf, sizeof(buf), "a%-8dz", 1234);
+  EXPECT_STREQ("a1234    z", buf);
+
+  async_safe_format_buffer(buf, sizeof(buf), "A%-11sZ", "abcdef");
+  EXPECT_STREQ("Aabcdef     Z", buf);
+
+  async_safe_format_buffer(buf, sizeof(buf), "A%s:%dZ", "hello", 1234);
+  EXPECT_STREQ("Ahello:1234Z", buf);
+
+  async_safe_format_buffer(buf, sizeof(buf), "a%03d:%d:%02dz", 5, 5, 5);
+  EXPECT_STREQ("a005:5:05z", buf);
+
+  void* p = NULL;
+  async_safe_format_buffer(buf, sizeof(buf), "a%d,%pz", 5, p);
+  EXPECT_STREQ("a5,0x0z", buf);
+
+  async_safe_format_buffer(buf, sizeof(buf), "a%lld,%d,%d,%dz", 0x1000000000LL, 6, 7, 8);
+  EXPECT_STREQ("a68719476736,6,7,8z", buf);
+#else // __BIONIC__
+  GTEST_LOG_(INFO) << "This test does nothing.\n";
+#endif // __BIONIC__
+}
+
+TEST(async_safe_log, d_INT_MAX) {
+#if defined(__BIONIC__)
+  char buf[BUFSIZ];
+  async_safe_format_buffer(buf, sizeof(buf), "%d", INT_MAX);
+  EXPECT_STREQ("2147483647", buf);
+#else // __BIONIC__
+  GTEST_LOG_(INFO) << "This test does nothing.\n";
+#endif // __BIONIC__
+}
+
+TEST(async_safe_log, d_INT_MIN) {
+#if defined(__BIONIC__)
+  char buf[BUFSIZ];
+  async_safe_format_buffer(buf, sizeof(buf), "%d", INT_MIN);
+  EXPECT_STREQ("-2147483648", buf);
+#else // __BIONIC__
+  GTEST_LOG_(INFO) << "This test does nothing.\n";
+#endif // __BIONIC__
+}
+
+TEST(async_safe_log, ld_LONG_MAX) {
+#if defined(__BIONIC__)
+  char buf[BUFSIZ];
+  async_safe_format_buffer(buf, sizeof(buf), "%ld", LONG_MAX);
+#if defined(__LP64__)
+  EXPECT_STREQ("9223372036854775807", buf);
+#else
+  EXPECT_STREQ("2147483647", buf);
+#endif
+#else // __BIONIC__
+  GTEST_LOG_(INFO) << "This test does nothing.\n";
+#endif // __BIONIC__
+}
+
+TEST(async_safe_log, ld_LONG_MIN) {
+#if defined(__BIONIC__)
+  char buf[BUFSIZ];
+  async_safe_format_buffer(buf, sizeof(buf), "%ld", LONG_MIN);
+#if defined(__LP64__)
+  EXPECT_STREQ("-9223372036854775808", buf);
+#else
+  EXPECT_STREQ("-2147483648", buf);
+#endif
+#else // __BIONIC__
+  GTEST_LOG_(INFO) << "This test does nothing.\n";
+#endif // __BIONIC__
+}
+
+TEST(async_safe_log, lld_LLONG_MAX) {
+#if defined(__BIONIC__)
+  char buf[BUFSIZ];
+  async_safe_format_buffer(buf, sizeof(buf), "%lld", LLONG_MAX);
+  EXPECT_STREQ("9223372036854775807", buf);
+#else // __BIONIC__
+  GTEST_LOG_(INFO) << "This test does nothing.\n";
+#endif // __BIONIC__
+}
+
+TEST(async_safe_log, lld_LLONG_MIN) {
+#if defined(__BIONIC__)
+  char buf[BUFSIZ];
+  async_safe_format_buffer(buf, sizeof(buf), "%lld", LLONG_MIN);
+  EXPECT_STREQ("-9223372036854775808", buf);
+#else // __BIONIC__
+  GTEST_LOG_(INFO) << "This test does nothing.\n";
+#endif // __BIONIC__
+}
+
+TEST(async_safe_log, buffer_overrun) {
+#if defined(__BIONIC__)
+  char buf[BUFSIZ];
+  ASSERT_EQ(11, async_safe_format_buffer(buf, sizeof(buf), "hello %s", "world"));
+  EXPECT_STREQ("hello world", buf);
+  ASSERT_EQ(11, async_safe_format_buffer(buf, 8, "hello %s", "world"));
+  EXPECT_STREQ("hello w", buf);
+#else // __BIONIC__
+  GTEST_LOG_(INFO) << "This test does nothing.\n";
+#endif // __BIONIC__
+}