Exemple #1
0
bool CFat32Device::ReadFromCache(unsigned long sector, unsigned char *buffer)
{
  // round sector size down to page size
  unsigned long page = sector & ~(FAT_PAGE_SIZE / m_sectorsize - 1);
  FATCACHE::iterator it = m_cache.find(page);
  if (it != m_cache.end())
  {
    cacheHit++;
    CSector *cacheSector = (*it).second;
    cacheSector->IncrementUsage(timeGetTime());
    fast_memcpy(buffer, cacheSector->Get() + (sector - page)*m_sectorsize, m_sectorsize);
    return true;
  }
  return false;
}
Exemple #2
0
void CFat32Device::CachePage(unsigned long page, unsigned char *buffer)
{
  DWORD time = timeGetTime();
  if (m_cache.size() >= CACHE_SIZE)
  { // remove the last used cache
    FATCACHE::iterator lastUsed = m_cache.begin();
    //CStdString usage;
    unsigned long smallest = 0;
    for (FATCACHE::iterator it = m_cache.begin(); it != m_cache.end(); ++it)
    {
      if ((*it).second->Usage(time) > (*lastUsed).second->Usage(time))
        lastUsed = it;
      if ((*it).second->Usage(time) < smallest)
        smallest = (*it).second->Usage(time);
/*      CStdString log;
      if ((*it).second->Usage(time) > 0xFF)
        log = "FF ";
      else
        log.Format("%02x ", (*it).second->Usage());
      usage += log;*/
    }
    //CLog::Log(LOGDEBUG, "%s", usage.c_str());
    // lastUsed is the one we remove
    unsigned long oldpage = (*lastUsed).first;
    CSector *sector = (*lastUsed).second;
    m_cache.erase(lastUsed);
//    CLog::Log(LOGDEBUG, "Swapping page %i for page %i, oldest usage: %d (%d)", oldpage, page, sector->Usage(time), smallest);
#ifdef FAT32_ALLOW_WRITING
    // write it out to disk if dirty
    if (sector->IsDirty())
      WritePage(oldpage, sector->Get());
#endif
    delete sector;
  }
  // cache our page
  m_cache.insert(pair<unsigned int, CSector *>(page, new CSector(buffer, time)));
}