ftrace_reader/src/ftrace_controller_integrationtest.cc

/*
 * Copyright (C) 2017 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 <fstream>
#include <sstream>

#include "ftrace_reader/ftrace_controller.h"
#include "gmock/gmock.h"
#include "gtest/gtest.h"

using testing::HasSubstr;
using testing::Not;

namespace perfetto {
namespace {

const char kTracePath[] = "/sys/kernel/debug/tracing/trace";

std::string GetTraceOutput() {
  std::ifstream fin(kTracePath, std::ios::in);
  if (!fin) {
    ADD_FAILURE() << "Could not read trace output";
    return "";
  }
  std::ostringstream stream;
  stream << fin.rdbuf();
  fin.close();
  return stream.str();
}

TEST(FtraceController, ClearTrace) {
  FtraceController ftrace_controller;
  ftrace_controller.WriteTraceMarker("Hello, World!");
  ftrace_controller.ClearTrace();
  EXPECT_THAT(GetTraceOutput(), Not(HasSubstr("Hello, World!")));
}

TEST(FtraceController, TraceMarker) {
  FtraceController ftrace_controller;
  ftrace_controller.WriteTraceMarker("Hello, World!");
  EXPECT_THAT(GetTraceOutput(), HasSubstr("Hello, World!"));
}

TEST(FtraceController, EnableDisableEvent) {
  FtraceController ftrace_controller;
  ftrace_controller.EnableEvent("sched/sched_switch");
  sleep(1);
  EXPECT_THAT(GetTraceOutput(), HasSubstr("sched_switch"));

  ftrace_controller.DisableEvent("sched/sched_switch");
  ftrace_controller.ClearTrace();
  sleep(1);
  EXPECT_THAT(GetTraceOutput(), Not(HasSubstr("sched_switch")));
}

TEST(FtraceController, EnableDisableTracing) {
  FtraceController ftrace_controller;
  ftrace_controller.ClearTrace();
  EXPECT_TRUE(ftrace_controller.IsTracingEnabled());
  ftrace_controller.WriteTraceMarker("Before");
  ftrace_controller.DisableTracing();
  EXPECT_FALSE(ftrace_controller.IsTracingEnabled());
  ftrace_controller.WriteTraceMarker("During");
  ftrace_controller.EnableTracing();
  EXPECT_TRUE(ftrace_controller.IsTracingEnabled());
  ftrace_controller.WriteTraceMarker("After");
  EXPECT_THAT(GetTraceOutput(), HasSubstr("Before"));
  EXPECT_THAT(GetTraceOutput(), Not(HasSubstr("During")));
  EXPECT_THAT(GetTraceOutput(), HasSubstr("After"));
}

}  // namespace
}  // namespace perfetto