private int[] AllocateBlocks(int count)
{
if (count <= 0)
{
return(new int[0]);
}
var freeCount = UnallocatedHashEntries.Count > count ? count : UnallocatedHashEntries.Count;
var res = new List <int>();
if (freeCount > 0)
{
res.AddRange(UnallocatedHashEntries.Take(freeCount));
UnallocatedHashEntries.RemoveRange(0, freeCount);
var lastTable = TopLevel == 0 ? TopTable : TopTable.Tables[TopTable.EntryCount - 1];
var lastEntry = lastTable.Entries.FirstOrDefault(e => e.Block == res.Last());
if (lastEntry != null)
{
var index = lastTable.Entries.ToList().IndexOf(lastEntry);
lastTable.EntryCount = index + 1;
if (res.Last() + 1 > VolumeDescriptor.AllocatedBlockCount)
{
VolumeDescriptor.AllocatedBlockCount = res.Last() + 1;
Binary.EnsureBinarySize(GetRealAddressOfBlock(VolumeDescriptor.AllocatedBlockCount));
}
}
}
var toAlloc = count - freeCount;
if (toAlloc > 0)
{
switch (TopLevel)
{
case 0:
throw new NotImplementedException("Table upgrade from lvl 0 to 1 needed!");
case 1:
if (TopTable.EntryCount == 0xAA)
{
throw new NotImplementedException("Table upgrade from lvl 1 to 2 needed!");
}
//allocate a new table
var table = GetLevelNHashTable(TopTable.EntryCount, 0);
var tableEntry = TopTable.Entries[TopTable.EntryCount++];
tableEntry.RealBlock = table.Block;
tableEntry.Status = BlockStatus.Allocated;
TopTable.Tables.Add(table);
res.AddRange(AllocateBlocks(toAlloc));
break;
default:
throw new NotSupportedException("Unsupported level" + TopLevel);
}
}
return(res.ToArray());
}