private SizeBucket newBucket(int size) {
long offset = sizeMap.getLong(newBucketOffset);
SizeBucket bucket = new SizeBucket(offset);
bucket.count(0);
bucket.size(size);
bucket.prev(0);
bucket.next(0);
sizeMap.putLong(newBucketOffset, offset + bucketSize);
return bucket;
}
public void free(long position, int size) {
SizeBucket bucket = findSizeBucket(size);
if (bucket == null) {
// create a new bucket with that size and put it as the first element of
// bucket list for that size
bucket = newBucket(size);
sizeMap.putLong(sizeIndex(size), bucket.position);
} else if (bucket.count() == bucket.max()) {
SizeBucket newb = newBucket(size);
newb.prev(bucket.position);
newb.next(bucket.nextOffset());
bucket.next(newb.position);
bucket = newb;
}
bucket.put(position);
}
private void freeBucket(SizeBucket bucket) {
// First, we need to unlink from the list.
if (bucket.prevOffset() != 0) bucket.prev().next(bucket.nextOffset());
else sizeMap.putLong(sizeIndex(bucket.size()), bucket.nextOffset());
if (bucket.nextOffset() != 0) bucket.next().prev(bucket.prevOffset());
// Next, if this is not the last bucket block in the file, we want to swap
// the last into it so as to reclaim that space
long lastBucketPosition = sizeMap.getLong(newBucketOffset) - bucketSize;
if (lastBucketPosition != bucket.position) {
byte[] data = new byte[bucketSize];
try {
read(lastBucketPosition, bucketSize).get(data);
write(bucket.position, bucketSize).put(data);
} catch (Throwable t) {
throw new HGException(t);
}
}
sizeMap.putLong(newBucketOffset, lastBucketPosition);
}
public long findAvailable(int size) {
for (SizeBucket bucket = findSizeBucket(size); bucket != null; bucket = bucket.next())
if (bucket.size() == size && bucket.count() > 0) return bucket.get();
return -1;
}