SnapshotItem(const IFileContainer *container, const Location &fileName, const struct RARHeaderDataEx &info, SnapshotItem *parent) :
::VFS::SnapshotItem(container, unpackedSize(info), parent)
{
m_data.path = QString::fromWCharArray(info.FileNameW);
m_data.fileName = fileName;
m_data.fileSize = totalSize();
m_data.lastModified = fromDosTime(info.FileTime);
}
void PtexReader::readFace(int levelid, Level* level, int faceid)
{
// temporarily release cache lock so other threads can proceed
_cache->cachelock.unlock();
// get read lock and make sure we still need to read
FaceData*& face = level->faces[faceid];
AutoMutex locker(readlock);
if (face) {
// another thread must have read it while we were waiting
_cache->cachelock.lock();
// make sure it's still there now that we have the lock
if (face) {
face->ref();
return;
}
_cache->cachelock.unlock();
}
// Go ahead and read the face, and read nearby faces if
// possible. The goal is to coalesce small faces into single
// runs of consecutive reads to minimize seeking and take
// advantage of read-ahead buffering.
// Try to read as many faces as will fit in BlockSize. Use the
// in-memory size rather than the on-disk size to prevent flooding
// the memory cache. And don't coalesce w/ tiled faces as these
// are meant to be read individually.
// scan both backwards and forwards looking for unread faces
int first = faceid, last = faceid;
int totalsize = 0;
FaceDataHeader fdh = level->fdh[faceid];
if (fdh.encoding() != enc_tiled) {
totalsize += unpackedSize(fdh, levelid, faceid);
int nfaces = int(level->fdh.size());
while (1) {
int f = first-1;
if (f < 0 || level->faces[f]) break;
fdh = level->fdh[f];
if (fdh.encoding() == enc_tiled) break;
int size = totalsize + unpackedSize(fdh, levelid, f);
if (size > BlockSize) break;
first = f;
totalsize = size;
}
while (1) {
int f = last+1;
if (f >= nfaces || level->faces[f]) break;
fdh = level->fdh[f];
if (fdh.encoding() == enc_tiled) break;
int size = totalsize + unpackedSize(fdh, levelid, f);
if (size > BlockSize) break;
last = f;
totalsize = size;
}
}
// read all faces in range
// keep track of extra faces we read so we can add them to the cache later
std::vector<FaceData*> extraFaces;
extraFaces.reserve(last-first);
for (int i = first; i <= last; i++) {
fdh = level->fdh[i];
// skip faces with zero size (which is true for level-0 constant faces)
if (fdh.blocksize()) {
FaceData*& face = level->faces[i];
readFaceData(level->offsets[i], fdh, getRes(levelid, i), levelid, face);
if (i != faceid) extraFaces.push_back(face);
}
}
// reacquire cache lock, then unref extra faces to add them to the cache
_cache->cachelock.lock();
for (size_t i = 0, size = extraFaces.size(); i < size; i++)
extraFaces[i]->unref();
}