PollEvent.cc

/*
 * Copyright (c) 2008-2014, Pedigree Developers
 *
 * Please see the CONTRIB file in the root of the source tree for a full
 * list of contributors.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */
 
#include "modules/subsys/posix/PollEvent.h"
#include "pedigree/kernel/Log.h"
 
#include "modules/system/vfs/File.h"
 
static void pollEventHandler(uint8_t* pBuffer);
 
PollEvent::PollEvent() : Event(0, false), m_pSemaphore(0), m_pFd(0), m_nREvent(0), m_pFile(0) {}
 
PollEvent::PollEvent(Semaphore* pSemaphore, struct pollfd* fd, int revent, File* pFile)
    : Event(reinterpret_cast<uintptr_t>(&pollEventHandler), false),
      m_pSemaphore(pSemaphore),
      m_pFd(fd),
      m_nREvent(revent),
      m_pFile(pFile) {
  assert(pSemaphore);
}
 
PollEvent::~PollEvent() {}
 
void PollEvent::fire() {
  m_pFd->revents |= m_nREvent;
 
  m_pSemaphore->release();
}
 
size_t PollEvent::serialize(uint8_t* pBuffer) {
  void* alignedBuffer = ASSUME_ALIGNMENT(pBuffer, sizeof(size_t));
  size_t* pBuf = reinterpret_cast<size_t*>(alignedBuffer);
  pBuf[0] = EventNumbers::PollEvent;
  pBuf[1] = reinterpret_cast<size_t>(m_pSemaphore);
  pBuf[2] = reinterpret_cast<size_t>(m_pFd);
  pBuf[3] = static_cast<size_t>(m_nREvent);
  pBuf[4] = reinterpret_cast<size_t>(m_pFile);
 
  return 5 * sizeof(size_t);
}
 
bool PollEvent::unserialize(uint8_t* pBuffer, PollEvent& event) {
  void* alignedBuffer = ASSUME_ALIGNMENT(pBuffer, sizeof(size_t));
  size_t* pBuf = reinterpret_cast<size_t*>(alignedBuffer);
  if (pBuf[0] != EventNumbers::PollEvent)
    return false;
 
  event.m_pSemaphore = reinterpret_cast<Semaphore*>(pBuf[1]);
  event.m_pFd = reinterpret_cast<struct pollfd*>(pBuf[2]);
  event.m_nREvent = static_cast<int>(pBuf[3]);
  event.m_pFile = reinterpret_cast<File*>(pBuf[4]);
 
  return true;
}
 
void pollEventHandler(uint8_t* pBuffer) {
  PollEvent e;
  if (!PollEvent::unserialize(pBuffer, e)) {
    FATAL("PollEventHandler: unable to unserialize event!");
  }
  e.fire();
}