// Copyright 2020 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "services/tracing/public/cpp/system_tracing_service.h"

#include <sys/un.h>
#include <unistd.h>

#include <cstdint>
#include <optional>

#include "base/files/scoped_temp_dir.h"
#include "base/task/single_thread_task_runner.h"
#include "base/test/bind.h"
#include "base/test/task_environment.h"
#include "services/tracing/perfetto/system_test_utils.h"
#include "services/tracing/perfetto/test_utils.h"
#include "services/tracing/public/cpp/perfetto/perfetto_traced_process.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace tracing {

const char* kProducerSockEnvName = "PERFETTO_PRODUCER_SOCK_NAME";

namespace {

class SystemTracingServiceTest : public testing::Test {
 public:
  SystemTracingServiceTest()
      : task_environment_(base::test::TaskEnvironment::MainThreadType::IO) {}

  void SetUp() override {
    // The test connects to the mock system service.
    ASSERT_TRUE(temp_dir_.CreateUniqueTempDir());
    system_service_ = std::make_unique<MockSystemService>(temp_dir_);

    // Save the current producer socket name from env if currently set.
    const auto* producer_sock_name_env = getenv(kProducerSockEnvName);
    if (producer_sock_name_env) {
      saved_producer_sock_env_ = producer_sock_name_env;
    }
    // Override the default system producer socket.
    ASSERT_EQ(0, setenv(kProducerSockEnvName,
                        system_service_->producer().c_str(), 1));
  }

  void TearDown() override {
    // Restore the value of Perfetto producer socket name env variable.
    if (saved_producer_sock_env_) {
      ASSERT_EQ(0, setenv(kProducerSockEnvName,
                          saved_producer_sock_env_->c_str(), 1));
    } else {
      ASSERT_EQ(0, unsetenv(kProducerSockEnvName));
    }

    system_service_ = nullptr;
    task_environment_.RunUntilIdle();
  }

 protected:
  base::test::TaskEnvironment task_environment_;
  tracing::TracedProcessForTesting traced_process_{
      base::SingleThreadTaskRunner::GetCurrentDefault()};
  base::ScopedTempDir temp_dir_;
  std::unique_ptr<MockSystemService> system_service_;
  std::optional<std::string> saved_producer_sock_env_;
};

// Test the OpenProducerSocket implementation. Expect a valid socket file
// descriptor returned in the callback.
TEST_F(SystemTracingServiceTest, OpenProducerSocket) {
  auto sts = std::make_unique<SystemTracingService>();
  bool callback_called = false;

  base::RunLoop run_loop;
  auto callback = base::BindLambdaForTesting([&](base::File file) {
    callback_called = true;
    ASSERT_TRUE(file.IsValid());
    run_loop.Quit();
  });

  std::optional<bool> socket_connected;
  auto on_connect_callback = base::BindLambdaForTesting(
      [&](bool connected) { socket_connected = connected; });

  sts->OpenProducerSocketForTesting(std::move(callback),
                                    std::move(on_connect_callback));
  ASSERT_FALSE(callback_called);
  run_loop.Run();
  ASSERT_TRUE(callback_called);
  ASSERT_TRUE(socket_connected.has_value());
  ASSERT_TRUE(*socket_connected);
}

// Test the OpenProducerSocket implementation with a nonexistent socket. Expect
// an invalid socket file descriptor returned in the callback.
TEST_F(SystemTracingServiceTest, OpenProducerSocket_Nonexistent) {
  auto sts = std::make_unique<SystemTracingService>();
  bool callback_called = false;

  // Set the producer socket name to a nonexistent path.
  ASSERT_EQ(0, setenv(kProducerSockEnvName, "nonexistent_socket", 1));

  base::RunLoop run_loop;
  auto callback = base::BindLambdaForTesting([&](base::File file) {
    callback_called = true;
    // OpenProducerSocket fails and returns an invalid socket file descriptor.
    ASSERT_FALSE(file.IsValid());
    run_loop.Quit();
  });

  std::optional<bool> socket_connected;
  auto on_connect_callback = base::BindLambdaForTesting(
      [&](bool connected) { socket_connected = connected; });
  sts->OpenProducerSocketForTesting(std::move(callback),
                                    std::move(on_connect_callback));

  ASSERT_FALSE(callback_called);
  run_loop.Run();
  ASSERT_TRUE(callback_called);
  ASSERT_TRUE(socket_connected.has_value());
  ASSERT_FALSE(*socket_connected);
}

// Test the OpenProducerSocket implementation through mojo. Expect that the
// callback runs when invoked through mojo.
TEST_F(SystemTracingServiceTest, BindAndPassPendingRemote) {
  auto sts = std::make_unique<SystemTracingService>();
  bool callback_called = false;

  // Bind the pending remote on the current thread.
  mojo::Remote<mojom::SystemTracingService> remote;
  remote.Bind(sts->BindAndPassPendingRemote(), nullptr);

  base::RunLoop run_loop;
  auto callback = base::BindLambdaForTesting([&](base::File file) {
    callback_called = true;
    ASSERT_TRUE(file.IsValid());
    run_loop.Quit();
  });

  remote->OpenProducerSocket(std::move(callback));
  ASSERT_FALSE(callback_called);
  run_loop.Run();
  ASSERT_TRUE(callback_called);
}

// Test the OpenProducerSocket implementation through mojo with a nonexistent
// socket. Expect that the callback runs with an invalid socket file descriptor
TEST_F(SystemTracingServiceTest, BindAndPassPendingRemote_Nonexistent) {
  auto sts = std::make_unique<SystemTracingService>();
  bool callback_called = false;

  // Set the producer socket name to a nonexistent path.
  ASSERT_EQ(0, setenv(kProducerSockEnvName, "nonexistent_socket", 1));

  // Bind the pending remote on the current thread.
  mojo::Remote<mojom::SystemTracingService> remote;
  remote.Bind(sts->BindAndPassPendingRemote(), nullptr);

  base::RunLoop run_loop;
  auto callback = base::BindLambdaForTesting([&](base::File file) {
    callback_called = true;
    ASSERT_FALSE(file.IsValid());
    run_loop.Quit();
  });

  remote->OpenProducerSocket(std::move(callback));
  ASSERT_FALSE(callback_called);
  run_loop.Run();
  ASSERT_TRUE(callback_called);
}

TEST_F(SystemTracingServiceTest, BindAndPassPendingRemote_NonexistentLong) {
  auto sts = std::make_unique<SystemTracingService>();
  bool callback_called = false;

  // Set the producer socket name to a long nonexistent path.
  std::string sock_name;
  while (sock_name.size() < 1024) {
    sock_name.append("nonexistent/");
  }
  ASSERT_GT(sock_name.size(), sizeof(sockaddr_un::sun_path));
  ASSERT_EQ(0, setenv(kProducerSockEnvName, sock_name.c_str(), 1));

  // Bind the pending remote on the current thread.
  mojo::Remote<mojom::SystemTracingService> remote;
  remote.Bind(sts->BindAndPassPendingRemote(), nullptr);

  base::RunLoop run_loop;
  auto callback = base::BindLambdaForTesting([&](base::File file) {
    callback_called = true;
    ASSERT_FALSE(file.IsValid());
    run_loop.Quit();
  });

  remote->OpenProducerSocket(std::move(callback));
  ASSERT_FALSE(callback_called);
  run_loop.Run();
  ASSERT_TRUE(callback_called);
}

}  // namespace
}  // namespace tracing