/// <summary>
/// Attempts to download/retrieve from cache the key.
/// </summary>
/// <param name="key">index of the file to retrieve</param>
/// <returns>stream or null</returns>
private SymbolStoreFile GetSymbolStoreFile(SymbolStoreKey key)
{
Debug.Assert(IsSymbolStoreEnabled);
try
{
return(_symbolStore.GetFile(key, CancellationToken.None).GetAwaiter().GetResult());
}
catch (Exception ex) when(ex is UnauthorizedAccessException || ex is BadImageFormatException || ex is IOException)
{
Trace.TraceError("Exception: {0}", ex.ToString());
}
return(null);
}
/// <summary>
/// Downloads the file or retrieves it from a cache from the symbol store chain.
/// </summary>
/// <param name="key">symbol index to retrieve</param>
/// <param name="token">to cancel requests</param>
/// <returns>file or null if not found</returns>
public async Task <SymbolStoreFile> GetFile(SymbolStoreKey key, CancellationToken token)
{
SymbolStoreFile file = await GetFileInner(key, token);
if (file == null)
{
if (_backingStore != null)
{
file = await _backingStore.GetFile(key, token);
if (file != null)
{
await WriteFileInner(key, file);
// Reset stream to the beginning for next symbol store
file.Stream.Position = 0;
}
}
}
return(file);
}
