/// <summary>
/// Adds segments, returning the initial segment of the newly added chain.
/// </summary>
/// <param name="segmentsToObtain"></param>
/// <returns>Returns the initial segment of the newly added chain.</returns>
private Segment *AddSegments(int segmentsToObtain)
{
Segment *segment;
if (_pool.TryPop(segmentsToObtain, out segment) == segmentsToObtain)
{
if (Head == null)
{
Head = segment;
_tail = GetTailOrThis(segment);
}
else
{
// attach the new segment to the end O(1)
_tail->Next = segment;
_tail = GetTailOrThis(segment); // rewrite tail O(number of segments added)
}
var s = segment;
while (s != null)
{
_capacity += s->Length;
s = s->Next;
}
return(segment);
}
else
{
// not enough elements taken, release and throw
_pool.Push(segment);
throw new Exception("Not enough memory in the pool");
}
}
public static unsafe Segment *Pop(this ISegmentPool pool)
{
Segment *result;
if (pool.TryPop(out result) == false)
{
throw new InvalidOperationException("Pool cannot provide more memory");
}
return(result);
}