text: /*
   *  Copyright (c) 2018, The OpenThread Authors.
   *  All rights reserved.
   *
   *  Redistribution and use in source and binary forms, with or without
   *  modification, are permitted provided that the following conditions are met:
   *  1. Redistributions of source code must retain the above copyright
   *     notice, this list of conditions and the following disclaimer.
   *  2. Redistributions in binary form must reproduce the above copyright
   *     notice, this list of conditions and the following disclaimer in the
   *     documentation and/or other materials provided with the distribution.
   *  3. Neither the name of the copyright holder nor the
   *     names of its contributors may be used to endorse or promote products
   *     derived from this software without specific prior written permission.
   *
   *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
   *  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   *  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   *  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
   *  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
   *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
   *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   *  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
   *  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   *  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   *  POSSIBILITY OF SUCH DAMAGE.
   */
  
  #include "platform-posix.h"
  
  #if OPENTHREAD_POSIX_VIRTUAL_TIME
  
  #include <stdbool.h>
  #include <stdio.h>
  #include <string.h>
  
  #include <openthread/platform/alarm-micro.h>
  #include <openthread/platform/alarm-milli.h>
  #include <openthread/platform/diag.h>
  
  #define US_PER_MS 1000
  
  extern uint64_t sNow; // microseconds
  
  static bool     sIsMsRunning = false;
  static uint32_t sMsAlarm     = 0;
  
  static bool     sIsUsRunning = false;
  static uint32_t sUsAlarm     = 0;
  
  void platformAlarmInit(uint32_t aSpeedUpFactor)
  {
      OT_UNUSED_VARIABLE(aSpeedUpFactor);
  
      sNow = 0;
  }
  
  uint64_t platformAlarmGetNow(void)
  {
      return sNow;
  }
  
  void platformAlarmAdvanceNow(uint64_t aDelta)
  {
      sNow += aDelta;
  }
  
  uint32_t otPlatAlarmMilliGetNow(void)
  {
      return (uint32_t)(sNow / US_PER_MS);
  }
  
  void otPlatAlarmMilliStartAt(otInstance *aInstance, uint32_t aT0, uint32_t aDt)
  {
      OT_UNUSED_VARIABLE(aInstance);
  
      sMsAlarm     = aT0 + aDt;
      sIsMsRunning = true;
  }
  
  void otPlatAlarmMilliStop(otInstance *aInstance)
  {
      OT_UNUSED_VARIABLE(aInstance);
  
      sIsMsRunning = false;
  }
  
  uint32_t otPlatAlarmMicroGetNow(void)
  {
      return (uint32_t)sNow;
  }
  
  void otPlatAlarmMicroStartAt(otInstance *aInstance, uint32_t aT0, uint32_t aDt)
  {
      OT_UNUSED_VARIABLE(aInstance);
  
      sUsAlarm     = aT0 + aDt;
      sIsUsRunning = true;
  }
  
  void otPlatAlarmMicroStop(otInstance *aInstance)
  {
      OT_UNUSED_VARIABLE(aInstance);
  
      sIsUsRunning = false;
  }
  
  int32_t platformAlarmGetNext(void)
  {
      int32_t remaining = INT32_MAX;
  
      if (sIsMsRunning)
      {
          int32_t milli = (int32_t)(sMsAlarm - otPlatAlarmMilliGetNow());
  
          remaining = milli * US_PER_MS;
  
          if (remaining < 0 && milli > 0)
          {
              remaining = INT32_MAX;
          }
      }
  
  #if OPENTHREAD_CONFIG_ENABLE_PLATFORM_USEC_TIMER
  
      if (sIsUsRunning)
      {
          int32_t micro = (int32_t)(sUsAlarm - otPlatAlarmMicroGetNow());
  
          if (remaining > micro)
          {
              remaining = micro;
          }
      }
  
  #endif // OPENTHREAD_CONFIG_ENABLE_PLATFORM_USEC_TIMER
  
      return remaining;
  }
  
  void platformAlarmProcess(otInstance *aInstance)
  {
      int32_t remaining;
  
      if (sIsMsRunning)
      {
          remaining = (int32_t)(sMsAlarm - otPlatAlarmMilliGetNow());
  
          if (remaining <= 0)
          {
              sIsMsRunning = false;
  
  #if OPENTHREAD_ENABLE_DIAG
  
              if (otPlatDiagModeGet())
              {
                  otPlatDiagAlarmFired(aInstance);
              }
              else
  #endif
              {
                  otPlatAlarmMilliFired(aInstance);
              }
          }
      }
  
  #if OPENTHREAD_CONFIG_ENABLE_PLATFORM_USEC_TIMER
  
      if (sIsUsRunning)
      {
          remaining = (int32_t)(sUsAlarm - otPlatAlarmMicroGetNow());
  
          if (remaining <= 0)
          {
              sIsUsRunning = false;
  
              otPlatAlarmMicroFired(aInstance);
          }
      }
  
  #endif // OPENTHREAD_CONFIG_ENABLE_PLATFORM_USEC_TIMER
  }
  
  #endif // OPENTHREAD_POSIX_VIRTUAL_TIME
  