const T& List<T>::Back () const
{
if (Empty())
{
std::cerr << "** List error: Back() called on empty list\n";
}
return *rBegin();
}
void QGalleryTrackerResultSetPrivate::synchronize()
{
const const_row_iterator rEnd(rCache.values.constEnd(), tableWidth);
const const_row_iterator iEnd(iCache.values.constEnd(), tableWidth);
const_row_iterator rBegin(rCache.values.constBegin(), tableWidth);
const_row_iterator iBegin(iCache.values.constBegin(), tableWidth);
const int rStep = qMax(64, rEnd - rBegin) / 16;
const int iStep = qMax(64, iEnd - iBegin) / 16;
for (bool equal = true; equal && rBegin != rEnd && iBegin != iEnd; ) {
bool changed = false;
do { // Skip over identical rows.
if ((equal = rBegin.isEqual(iBegin, identityWidth))
&& !(changed = !rBegin.isEqual(iBegin, identityWidth, tableWidth))) {
++rBegin;
++iBegin;
} else {
break;
}
} while (iBegin != rEnd && iBegin != iEnd);
if (changed) {
const_row_iterator rIt = rBegin;
const_row_iterator iIt = iBegin;
do { // Skip over rows with equal IDs but different values.
if ((equal = rIt.isEqual(iIt, identityWidth))
&& rIt.isEqual(iIt, identityWidth, tableWidth)) {
++rIt;
++iIt;
} else {
++rIt;
++iIt;
break;
}
} while (rIt != rEnd && iIt != iEnd);
const int rIndex = rCacheIndex(rBegin);
const int iIndex = iCacheIndex(iBegin);
const int count = iIt - iBegin;
postSyncEvent(SyncEvent::updateEvent(rIndex, iIndex, count));
rBegin = rIt;
iBegin = iIt;
continue;
} else if (equal) {
postSyncEvent(SyncEvent::finishEvent(rCacheIndex(rBegin), iCacheIndex(iBegin)));
return;
}
const_row_iterator rOuterEnd = rBegin + ((((rEnd - rBegin) + iStep - 1) / rStep) * rStep);
const_row_iterator iOuterEnd = iBegin + ((((iEnd - iBegin) + iStep - 1) / iStep) * iStep);
const_row_iterator rInnerEnd = qMin(rBegin + rStep * 2, rEnd);
const_row_iterator iInnerEnd = qMin(iBegin + iStep * 2, iEnd);
for (const_row_iterator rOuter = rBegin, iOuter = iBegin;
!equal && rOuter != rOuterEnd && iOuter != iOuterEnd;
rOuter += rStep, iOuter += iStep) {
for (const_row_iterator rInner = rBegin, iInner = iBegin;
rInner != rInnerEnd && iInner != iInnerEnd;
++rInner, ++iInner) {
if ((equal = rInner.isEqual(iOuter, identityWidth))) {
const_row_iterator rIt;
const_row_iterator iIt;
do {
rIt = rInner;
iIt = iOuter;
} while (rInner-- != rBegin && iOuter-- != iBegin
&& rInner.isEqual(iOuter, identityWidth));
const int rIndex = rCacheIndex(rOuter);
const int iIndex = iCacheIndex(iBegin);
const int rCount = rIt - rBegin;
const int iCount = iIt - iBegin;
postSyncEvent(SyncEvent::replaceEvent(rIndex, rCount, iIndex, iCount));
rBegin = rIt;
iBegin = iIt;
break;
} else if ((equal = iInner.isEqual(rOuter, identityWidth))) {
const_row_iterator rIt;
const_row_iterator iIt;
do {
rIt = rOuter;
iIt = iInner;
} while (iInner-- != iBegin && rOuter-- != rBegin
&& iInner.isEqual(rOuter, identityWidth));
const int rIndex = rCacheIndex(rBegin);
const int iIndex = iCacheIndex(iOuter);
const int rCount = rIt - rBegin;
const int iCount = iIt - iBegin;
postSyncEvent(SyncEvent::replaceEvent(rIndex, rCount, iIndex, iCount));
rBegin = rIt;
iBegin = iIt;
break;
}
}
}
}
postSyncEvent(SyncEvent::finishEvent(rCacheIndex(rBegin), iCacheIndex(iBegin)));
}
