cyber: add unit tests for shared_library

cyber/class_loader/shared_library/BUILD

-load("@rules_cc//cc:defs.bzl", "cc_library")
+load("@rules_cc//cc:defs.bzl", "cc_binary", "cc_library", "cc_test")
 load("//tools:cpplint.bzl", "cpplint")
 
 package(default_visibility = ["//visibility:public"])
@@ -18,4 +18,37 @@ cc_library(
     hdrs = ["exceptions.h"],
 )
 
+cc_binary(
+    name = "libsample.so",
+    testonly = True,
+    linkshared = True,
+    linkstatic = False,
+    visibility = ["//visibility:private"],
+    deps = [
+        ":sample_lib",
+    ],
+)
+
+cc_library(
+    name = "sample_lib",
+    testonly = True,
+    srcs = ["sample.cc"],
+    hdrs = ["sample.h"],
+    linkopts = ["-lm"],
+    visibility = ["//visibility:private"],
+)
+
+cc_test(
+    name = "shared_library_test",
+    size = "small",
+    srcs = ["shared_library_test.cc"],
+    data = [
+        ":libsample.so",
+    ],
+    deps = [
+        ":shared_library",
+        "@com_google_googletest//:gtest_main",
+    ],
+)
+
 cpplint()

cyber/class_loader/shared_library/sample.cc

+/******************************************************************************
+ * Copyright 2020 The Apollo Authors. All Rights Reserved.
+ *
+ * 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 "cyber/class_loader/shared_library/sample.h"
+
+#include <cmath>
+
+int sample_add(int x, int y) { return x + y; }
+
+double sample_sin(double x) { return std::sin(x); }

cyber/class_loader/shared_library/sample.h

+/******************************************************************************
+ * Copyright 2020 The Apollo Authors. All Rights Reserved.
+ *
+ * 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.
+ *****************************************************************************/
+#ifndef CYBER_CLASS_LOADER_SHARED_LIBRARY_SAMPLE_H_
+#define CYBER_CLASS_LOADER_SHARED_LIBRARY_SAMPLE_H_
+
+extern "C" int sample_add(int a, int b);
+extern "C" double sample_sin(double x);
+
+#endif  // CYBER_CLASS_LOADER_SHARED_LIBRARY_SAMPLE_H_

cyber/class_loader/shared_library/shared_library.cc

@@ -19,7 +19,7 @@
 // Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
 // and Contributors.
 //
-// SPDX-License-Identifier:	BSL-1.0
+// SPDX-License-Identifier: BSL-1.0
 //
 #include "cyber/class_loader/shared_library/shared_library.h"
 

cyber/class_loader/shared_library/shared_library_test.cc

+/******************************************************************************
+ * Copyright 2020 The Apollo Authors. All Rights Reserved.
+ *
+ * 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 "cyber/class_loader/shared_library/shared_library.h"
+
+#include <cmath>
+
+#include "gtest/gtest.h"
+
+namespace {
+
+const std::string& SAMPLE_LIB =
+    "/apollo/bazel-bin/cyber/class_loader/shared_library/libsample.so";
+constexpr double epsilon = 1.0e-8;
+
+}  // namespace
+
+namespace apollo {
+namespace cyber {
+namespace class_loader {
+
+TEST(SharedLibraryTest, symbol_test_1) {
+  auto shared_lib = std::make_shared<SharedLibrary>();
+  EXPECT_TRUE(shared_lib->GetPath().empty());
+  EXPECT_FALSE(shared_lib->IsLoaded());
+
+  EXPECT_NO_THROW(shared_lib->Load(SAMPLE_LIB));
+  EXPECT_TRUE(shared_lib->IsLoaded());
+
+  EXPECT_THROW(shared_lib->Load(SAMPLE_LIB), LibraryAlreadyLoadedException);
+
+  EXPECT_TRUE(shared_lib->HasSymbol("sample_add"));
+  auto symbol = shared_lib->GetSymbol("sample_add");
+  EXPECT_TRUE(symbol != nullptr);
+
+  typedef int (*BinaryFunc)(int, int);
+  auto pf = reinterpret_cast<BinaryFunc>(symbol);
+  EXPECT_EQ(pf(3, 5), 8);
+  shared_lib->Unload();
+}
+
+TEST(SharedLibraryTest, symbol_test_2) {
+  auto shared_lib = std::make_shared<SharedLibrary>(SAMPLE_LIB);
+  EXPECT_TRUE(shared_lib->IsLoaded());
+
+  typedef double (*UnaryFunc)(double);
+  auto symbol = shared_lib->GetSymbol("sample_sin");
+  EXPECT_TRUE(symbol != nullptr);
+
+  auto sample_sin = reinterpret_cast<UnaryFunc>(symbol);
+  EXPECT_NEAR(sample_sin(M_PI / 2), 1.0, epsilon);
+
+  shared_lib->Unload();
+}
+
+}  // namespace class_loader
+}  // namespace cyber
+}  // namespace apollo