public async Task <ICacheEntry> GetOrAddAsync(string key, Func <string, Stream, ICacheControl, Task> valueFactory, ICacheControl cacheControl, CancellationToken ct)
{
using (await _rwLock.ReadLockAsync())
{
ICacheEntry found = GetInternal(key);
if (!(found is EmptyCacheEntry))
{
found.Ref(); // this entry remain valid after releasing the lock
return(found);
}
}
using (await _rwLock.WriteLockAsync())
{
ICacheEntry found = GetInternal(key);
if (!(found is EmptyCacheEntry))
{
found.Ref(); // this entry remain valid after releasing the lock
return(found);
}
var randomPath = await _fs.WriteAtomicAsync((sink, cancel) => valueFactory(key, sink, cacheControl), _cacheTmpPath, ct).ConfigureAwait(false);
var tmpEntry = new DiskCacheEntry(key, randomPath, this);
if (!cacheControl.NoStore)
{
SetInternal(key, tmpEntry);
}
var entry = GetInternal(key);
entry.Ref();
return(entry);
}
}
public async Task <ICacheEntry> GetAsync(string key, CancellationToken ct)
{
using (await _rwLock.ReadLockAsync())
{
ICacheEntry entry = GetInternal(key);
entry.Ref();
return(entry);
}
}