public int InsertPage(byte[] buffer, int size)
{
var hashKey = new HashKey(buffer, size);
var key = ConvertToKey(hashKey);
var pageByKey = storage.Pages.GetIndex(Tables.Pages.Indices.ByKey);
var pageData = storage.Pages.GetIndex(Tables.Pages.Indices.Data);
var result = pageByKey.Read(Snapshot, key, writeBatch.Value);
if (result != null)
{
var id = result.Reader.ToStringValue();
ushort version;
var page = LoadJson(storage.Pages, id, writeBatch.Value, out version);
if (page == null)
throw new InvalidOperationException(string.Format("Could not find page '{0}'. Probably data is corrupted.", id));
var usageCount = page.Value<int>("usage_count");
page["usage_count"] = usageCount + 1;
storage.Pages.Add(writeBatch.Value, id, page, version);
return page.Value<int>("id");
}
var newId = IdGenerator.GetNextIdForTable(storage.Pages);
var newKey = CreateKey(newId);
var newPage = new RavenJObject
{
{"id", newId},
{"page_strong_hash", hashKey.Strong},
{"page_weak_hash", hashKey.Weak},
{"usage_count", 0}
};
storage.Pages.Add(writeBatch.Value, newKey, newPage, 0);
pageData.Add(writeBatch.Value, newKey, buffer, 0);
pageByKey.Add(writeBatch.Value, key, newKey);
return newId;
}
private void DeletePage(int pageId)
{
var key = CreateKey(pageId);
ushort version;
var page = LoadJson(storage.Pages, key, writeBatch.Value, out version);
var usageCount = page.Value<int>("usage_count");
if (usageCount <= 1)
{
var pageData = storage.Pages.GetIndex(Tables.Pages.Indices.Data);
var pagesByKey = storage.Pages.GetIndex(Tables.Pages.Indices.ByKey);
var strongHash = page.Value<byte[]>("page_strong_hash");
var weakHash = page.Value<int>("page_weak_hash");
var hashKey = new HashKey
{
Strong = strongHash,
Weak = weakHash
};
storage.Pages.Delete(writeBatch.Value, key, version);
pageData.Delete(writeBatch.Value, key);
pagesByKey.Delete(writeBatch.Value, ConvertToKey(hashKey));
}
else
{
page["usage_count"] = usageCount - 1;
storage.Pages.Add(writeBatch.Value, key, page, version);
}
}
public int InsertPage(byte[] buffer, int size)
{
var key = new HashKey(buffer, size);
Api.JetSetCurrentIndex(session, Pages, "by_keys");
Api.MakeKey(session, Pages, key.Weak, MakeKeyGrbit.NewKey);
Api.MakeKey(session, Pages, key.Strong, MakeKeyGrbit.None);
if (Api.TrySeek(session, Pages, SeekGrbit.SeekEQ))
{
Api.EscrowUpdate(session, Pages, tableColumnsCache.PagesColumns["usage_count"], 1);
return Api.RetrieveColumnAsInt32(session, Pages, tableColumnsCache.PagesColumns["id"]).Value;
}
var bookMarkBuffer = new byte[SystemParameters.BookmarkMost];
var actualSize = 0;
using (var update = new Update(session, Pages, JET_prep.Insert))
{
Api.SetColumn(session, Pages, tableColumnsCache.PagesColumns["page_strong_hash"], key.Strong);
Api.SetColumn(session, Pages, tableColumnsCache.PagesColumns["page_weak_hash"], key.Weak);
Api.JetSetColumn(session, Pages, tableColumnsCache.PagesColumns["data"], buffer, size, SetColumnGrbit.None, null);
try
{
update.Save(bookMarkBuffer, bookMarkBuffer.Length, out actualSize);
}
catch (EsentKeyDuplicateException)
{
// it means that page is being inserted by another thread
throw new ConcurrencyException("The same file page is being created");
}
}
Api.JetGotoBookmark(session, Pages, bookMarkBuffer, actualSize);
return Api.RetrieveColumnAsInt32(session, Pages, tableColumnsCache.PagesColumns["id"]).Value;
}
protected string ConvertToKey(HashKey hashKey)
{
return CreateKey(Encoding.UTF8.GetString(hashKey.Strong), hashKey.Weak);
}