private TransItem WriteStorageContext(StorageContext storageContext)
{
// write the context to disk
List <int> usedPages = null;
TransItem contextData = new TransItem();
// write the page table
if (null != storageContext.PageTable)
{
contextData.PageTableStartPage =
storageContext.PageTable.WritePageTableData(
this.dataFile, this.pageManager, out usedPages);
usedPages = storageContext.PageTable.GetStoragePages();
contextData.StoragePageList.AddRange(usedPages);
}
// write the resource index
if (null != storageContext.ResourceIndex)
{
contextData.ResourceIndexStartPage =
storageContext.ResourceIndex.WriteIndexData(
this.dataFile, this.pageManager, out usedPages);
usedPages = storageContext.ResourceIndex.GetStoragePages();
contextData.StoragePageList.AddRange(usedPages);
}
// write the reservation index
if (null != storageContext.ReservationIndex)
{
contextData.ReservationIndexStartPage =
storageContext.ReservationIndex.WriteIndexData(
this.dataFile, this.pageManager, out usedPages);
usedPages = storageContext.ReservationIndex.GetStoragePages();
contextData.StoragePageList.AddRange(usedPages);
}
// write allocated page list
if (null != storageContext.AllocatedPageList)
{
ListWriter <int> writer = new ListWriter <int>();
writer.WriteList(
this.dataFile, this.pageManager, storageContext.AllocatedPageList, out usedPages);
contextData.AllocatedPageListStartPage = usedPages[0];
contextData.StoragePageList.AddRange(usedPages);
}
// write freed page list
if (null != storageContext.FreedPageList)
{
ListWriter <int> writer = new ListWriter <int>();
writer.WriteList(
this.dataFile, this.pageManager, storageContext.FreedPageList, out usedPages);
contextData.FreedPageListStartPage = usedPages[0];
contextData.StoragePageList.AddRange(usedPages);
}
return(contextData);
}
/// <summary>
/// Writes the page table item to persitent storage as a list of items.
/// </summary>
/// <param name="stream">data file</param>
/// <param name="manager">object that keeps track of free pages in the file</param>
/// <param name="freedPages">list of pages to be freed when transaction commits</param>
/// <returns>index of the first page storing the list</returns>
public int WritePageTableData(FileStreamWrapper stream, StoragePageManager manager, out List <int> freedPages)
{
List <int> pageIdxList = null;
// create the writer
ListWriter <PageTableItem> writer = new ListWriter <PageTableItem>();
writer.WriteList(stream, manager, this.pageTable, out pageIdxList);
// update the list that stores the physical page idx
freedPages = this.pageTableStoragePages;
this.pageTableStoragePages = pageIdxList;
// return the index of the first page
return(this.pageTableStoragePages[0]);
}
/// <summary>
/// Writes the data item to persitent storage as a list of items.
/// </summary>
/// <param name="stream">data file to write to</param>
/// <param name="manager">object that keeps track of free pages in the file</param>
/// <param name="freedPages">list of pages to be freed when transaction commits</param>
/// <returns>index of the first page storing the list</returns>
public int WritePageManagerData(FileStreamWrapper stream)
{
lock (this.freePages)
{
this.writingSelf = true;
// make the list of pages to write
this.freePages.Insert(0, SelfWriteBarrier);
this.freePages.InsertRange(0, this.managerStoragePages);
// create writer
ListWriter <int> writer = new ListWriter <int>();
writer.WriteList(stream, this, this.freePages, out this.managerStoragePages);
this.writingSelf = false;
}
return(this.managerStoragePages[0]);
}
/// <summary>
/// Writes the index item to persitent storage as a list of items.
/// We handle deletes by setting the "value" in the map to null and
/// not writing any items whose value is null to persistent storage.
/// </summary>
/// <param name="stream">data file to write to</param>
/// <param name="manager">object that keeps track of free pages in the file</param>
/// <param name="freedPages">list of pages to be freed when transaction commits</param>
/// <returns>index of the first page storing the list</returns>
public int WriteIndexData(FileStreamWrapper stream, StoragePageManager manager, out List <int> freedPages)
{
List <int> pageIdxList = null;
// create the writer
ListWriter <IndexItem <T> > writer = new ListWriter <IndexItem <T> >();
writer.WriteList(
stream,
manager,
this.indexMap.Values.Where(c => c != null).ToList(),
out pageIdxList);
// update the list that stores the physical page idx
freedPages = this.indexStoragePages;
this.indexStoragePages = pageIdxList;
// return the index of the first page
return(this.indexStoragePages[0]);
}
/// <summary>
/// Writes the data item to persitent storage as a list of items.
/// </summary>
/// <param name="stream">data file to write to</param>
/// <param name="manager">object that keeps track of free pages in the file</param>
/// <param name="freedPages">list of pages to be freed when transaction commits</param>
/// <returns>index of the first page storing the list</returns>
public int WritePageManagerData(FileStreamWrapper stream)
{
lock (this.freePages)
{
this.writingSelf = true;
// make the list of pages to write
this.freePages.Insert(0, SelfWriteBarrier);
this.freePages.InsertRange(0, this.managerStoragePages);
// create writer
ListWriter<int> writer = new ListWriter<int>();
writer.WriteList(stream, this, this.freePages, out this.managerStoragePages);
this.writingSelf = false;
}
return this.managerStoragePages[0];
}
/// <summary>
/// Writes the data item to persitent storage as a list of items.
/// </summary>
/// <param name="stream">data file to write to</param>
/// <param name="manager">object that keeps track of free pages in the file</param>
/// <param name="freedPages">list of pages to be freed when transaction commits</param>
/// <returns>index of the first page storing the list</returns>
public int WriteTransactionTableData(FileStreamWrapper stream, StoragePageManager manager, out List<int> freedPages)
{
List<int> pageIdxList = null;
// create the writer
ListWriter<TransItem> writer = new ListWriter<TransItem>();
writer.WriteList(stream, manager, this.contextTable.Values.ToList() , out pageIdxList);
// update the list that stores the physical page idx
freedPages = this.contextTableStoragePages;
this.contextTableStoragePages = pageIdxList;
// return the index of the first page
return this.contextTableStoragePages[0];
}
