/// <inheritdoc/>
public async Task <uint> AllocateAsync(CancellationToken ct)
{
while (true)
{
// Get current value
var cur = await _indices.FindAsync <Bitmap>(_id, ct);
if (cur == null)
{
// Add new index
try {
var idx = new Bitmap();
var value = idx.Allocate();
await _indices.AddAsync(idx, ct, _id,
kWithStrongConsistency);
return(value);
}
catch (ConflictingResourceException) {
// Doc was added from another process/thread
}
}
else
{
// Get next free index
try {
var idx = new Bitmap(cur.Value);
var value = idx.Allocate();
await _indices.ReplaceAsync(cur, idx, ct,
kWithStrongConsistency);
return(value); // Success - return index
}
catch (ResourceOutOfDateException) {
// Etag is no match
}
}
}
}