/*

 * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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 */

#include "precompiled.hpp"

#include "runtime/os.hpp"

#include "utilities/ostream.hpp"

#include "utilities/spinYield.hpp"

#include "unittest.hpp"

// Some basic tests of SpinYield, using comparison of report output with

// expected results to verify state.  This is all very hard-wired to the

// current implementation of SpinYield, esp. the report function.

static void check_report(const SpinYield* spinner, const char* expected) {

  char buffer[100];

  stringStream s(buffer, sizeof(buffer));

  spinner->report(&s);

  ASSERT_STREQ(expected, buffer);

}

TEST(SpinYield, no_waiting) {

  SpinYield spinner;

  check_report(&spinner, "no waiting");

}

TEST(SpinYield, one_wait) {

  SpinYield spinner(100);

  spinner.wait();

  check_report(&spinner, os::is_MP() ? "spins = 1" : "yields = 1");

}

TEST(SpinYield, ten_waits) {

  SpinYield spinner(100, 100);

  for (unsigned i = 0; i < 10; ++i) {

    spinner.wait();

  }

  check_report(&spinner, os::is_MP() ? "spins = 10" : "yields = 10");

}

TEST(SpinYield, two_yields) {

  SpinYield spinner(0, 10);

  spinner.wait();

  spinner.wait();

  check_report(&spinner, "yields = 2");

}

TEST_VM(SpinYield, one_sleep) {

  SpinYield spinner(0, 0);

  spinner.wait();

  char buffer[100];

  stringStream s(buffer, sizeof(buffer));

  spinner.report(&s);

  const char* expected = "sleep = ";

  ASSERT_TRUE(strncmp(expected, buffer, strlen(expected)) == 0);

}

TEST_VM(SpinYield, one_spin_one_sleep) {

  SpinYield spinner(1, 0);

  spinner.wait();

  spinner.wait();

  char buffer[100];

  stringStream s(buffer, sizeof(buffer));

  spinner.report(&s);

  const char* expected_MP = "spins = 1, sleep = ";

  const char* expected_UP = "sleep = ";

  const char* expected = os::is_MP() ? expected_MP : expected_UP;

  ASSERT_TRUE(strncmp(expected, buffer, strlen(expected)) == 0);

}