/* Copyright (c) 2015, 2021, Oracle and/or its affiliates.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License, version 2.0,
   as published by the Free Software Foundation.

   This program is also distributed with certain software (including
   but not limited to OpenSSL) that is licensed under separate terms,
   as designated in a particular file or component or in included license
   documentation.  The authors of MySQL hereby grant you an additional
   permission to link the program and your derivative works with the
   separately licensed software that they have included with MySQL.

   This program 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 2.0, for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA */

#include "xplatform/my_xp_cond.h"

#ifdef _WIN32
My_xp_cond_win::My_xp_cond_win()
  :m_cond(static_cast<native_cond_t *>(malloc(sizeof(*m_cond))))
{}


My_xp_cond_win::~My_xp_cond_win()
{
  free(m_cond);
}


native_cond_t *My_xp_cond_win::get_native_cond()
{
  return m_cond;
}


/**
  Convert abstime to milliseconds on Windows.
*/
DWORD My_xp_cond_win::get_milliseconds(const struct timespec *abstime)
{
  if (abstime == NULL)
    return INFINITE;
#ifdef HAVE_STRUCT_TIMESPEC
  /*
    Convert timespec to millis and subtract current time.
    My_xp_util::getsystime() returns time in 100 ns units.
  */
  unsigned long long future = abstime->tv_sec * 1000 + abstime->tv_nsec / 1000000;
  unsigned long long now = My_xp_util::getsystime() / 10000;
  /* Don't allow the timeout to be negative. */
  if (future < now)
    return 0;
  return (DWORD)(future - now);
#else
  long long millis;
  union ft64 now;

  GetSystemTimeAsFileTime(&now.ft);

  /*
    Calculate time left to abstime
    - subtract start time from current time(values are in 100ns units)
    - convert to millisec by dividing with 10000
  */
  millis= (abstime->tv.i64 - now.i64) / 10000;

  /* Don't allow the timeout to be negative */
  if (millis < 0)
    return 0;

  /*
    Make sure the calculated timeout does not exceed original timeout
    value which could cause "wait for ever" if system time changes
  */
  if (millis > abstime->max_timeout_msec)
    millis= abstime->max_timeout_msec;

  if (millis > UINT_MAX)
    millis= UINT_MAX;

  return (DWORD)millis;
#endif
}


int My_xp_cond_win::init()
{
  InitializeConditionVariable(m_cond);
  return 0;
};


int My_xp_cond_win::destroy()
{
  return 0;
}


int My_xp_cond_win::timed_wait(native_mutex_t *mutex, const struct timespec *abstime)
{
  DWORD timeout= get_milliseconds(abstime);
  if (!SleepConditionVariableCS(m_cond, mutex, timeout))
    return ETIMEDOUT;

  return 0;
}


int My_xp_cond_win::wait(native_mutex_t *mutex)
{
  return timed_wait(mutex, NULL);
}


int My_xp_cond_win::signal()
{
  WakeConditionVariable(m_cond);
  return 0;
}


int My_xp_cond_win::broadcast()
{
  WakeAllConditionVariable(m_cond);
  return 0;
}
#else
My_xp_cond_pthread::My_xp_cond_pthread()
  :m_cond(static_cast<native_cond_t *>(malloc(sizeof(*m_cond))))
{}


My_xp_cond_pthread::~My_xp_cond_pthread()
{
  free(m_cond);
}

/* purecov: begin deadcode */
native_cond_t *My_xp_cond_pthread::get_native_cond()
{
  return m_cond;
}
/* purecov: end */

int My_xp_cond_pthread::init()
{
  if (m_cond == NULL)
    return -1;

  return pthread_cond_init(m_cond, NULL);
};


int My_xp_cond_pthread::destroy()
{
  return pthread_cond_destroy(m_cond);
}


int My_xp_cond_pthread::timed_wait(native_mutex_t *mutex, const struct timespec *abstime)
{
  return pthread_cond_timedwait(m_cond, mutex, abstime);
}


int My_xp_cond_pthread::wait(native_mutex_t *mutex)
{
  return pthread_cond_wait(m_cond, mutex);
}

/* purecov: begin deadcode */
int My_xp_cond_pthread::signal()
{
  return pthread_cond_signal(m_cond);
}
/* purecov: end */

int My_xp_cond_pthread::broadcast()
{
  return pthread_cond_broadcast(m_cond);
}
#endif
