/// <summary>
/// Switches page manager instance to normal mode.
/// All the changes made since the last EnterAtomicOperation() call are applied.
/// </summary>
public void ExitAtomicOperation()
{
if (_deferredUpdatesMode)
{
// write end marker to indicate that
// one can playback the recovery records
// without risking to corrupt the storage
_recoveryFile.WriteFinalMarker();
// switch off deferred update mode for normal page management operation
_deferredUpdatesMode = false;
foreach (var pageIndex in _recoveryFile.UpdatedPageIndexes)
{
UpdatePage(new Page(this, pageIndex, _recoveryFile.GetUpdatedPageContent(pageIndex)));
}
foreach (var index in _recoveryFile.DeletedPageIndexes)
{
RemovePage(index);
}
Flush(_storageStream);
_pagemap.Flush();
// now all are done, reset the recovery file
_recoveryFile.Reset();
}
}
public void CorrectlyRecoverSequentiallyUpdatedPage()
{
long index;
using (var fileSystemPageManager = new FileSystemPageManager(4096))
using (var storage = new Storage(fileSystemPageManager))
{
storage.OpenOrCreate(StoragePath);
var page = fileSystemPageManager.CreatePage();
index = page.Index;
}
string fileName;
using (var fileSystemPageManager = new FileSystemPageManager(4096))
using (var storage = new Storage(fileSystemPageManager))
using (var recoveryFile = new RecoveryFile(fileSystemPageManager, fileSystemPageManager.PageSize))
{
storage.OpenOrCreate(StoragePath);
var page = fileSystemPageManager.FetchPage(index);
index = page.Index;
fileSystemPageManager.Dispose();
Assert.AreEqual(index, page.Index);
Assert.AreNotEqual(0xff, page.Content[10]);
// Update twice with different bytes to make sure the latest one wins
page.Content[9] = 0xaa;
page.Content[10] = 0xaa;
recoveryFile.WriteUpdatePageRecord(page);
page.Content[10] = 0xff;
recoveryFile.WriteUpdatePageRecord(page);
recoveryFile.WriteFinalMarker();
fileName = recoveryFile.FileName;
}
Assert.True(File.Exists(fileName));
Assert.GreaterOrEqual(new FileInfo(fileName).Length, 1);
Assert.AreNotEqual(index, 0);
using (var manager = new FileSystemPageManager(4096))
using (var storage = new Storage(manager))
{
storage.OpenOrCreate(StoragePath);
var page = manager.FetchPage(index);
Assert.AreEqual(index, page.Index);
Assert.AreEqual(0xaa, page.Content[9]);
Assert.AreEqual(0xff, page.Content[10]);
}
}
public void CorrectlyApplyDeleteRecord()
{
long deleteIndex;
using (var fileSystemPageManager = new FileSystemPageManager(4096))
using (var storage = new Storage(fileSystemPageManager))
{
storage.OpenOrCreate(StoragePath);
deleteIndex = fileSystemPageManager.CreatePage().Index;
}
using (var fileSystemPageManager = new FileSystemPageManager(4096))
using (var storage = new Storage(fileSystemPageManager))
{
storage.OpenOrCreate(StoragePath);
Assert.True(fileSystemPageManager.PageExists(deleteIndex));
}
string fileName;
using (var fileSystemPageManager = new FileSystemPageManager(4096))
using (var storage = new Storage(fileSystemPageManager))
using (var recoveryFile = new RecoveryFile(fileSystemPageManager, fileSystemPageManager.PageSize))
{
storage.OpenOrCreate(StoragePath);
fileSystemPageManager.Dispose();
recoveryFile.WriteDeletePageRecord(deleteIndex);
recoveryFile.WriteFinalMarker();
fileName = recoveryFile.FileName;
}
Assert.True(File.Exists(fileName));
Assert.GreaterOrEqual(new FileInfo(fileName).Length, 1);
using (var manager = new FileSystemPageManager(4096))
using (var storage = new Storage(manager))
{
storage.OpenOrCreate(StoragePath);
Assert.False(manager.PageExists(deleteIndex));
Assert.AreEqual(deleteIndex, manager.CreatePage().Index);
}
}
public void CorrectlyRecoverResurrectedPage()
{
long index;
long resurrectIndex;
using (var fileSystemPageManager = new FileSystemPageManager(4096))
using (var storage = new Storage(fileSystemPageManager))
{
storage.OpenOrCreate(StoragePath);
var page = fileSystemPageManager.CreatePage();
index = page.Index;
}
using (var fileSystemPageManager = new FileSystemPageManager(4096))
using (var storage = new Storage(fileSystemPageManager))
{
storage.OpenOrCreate(StoragePath);
var page = fileSystemPageManager.FetchPage(index);
Assert.AreEqual(index, page.Index);
Assert.AreNotEqual(0xff, page.Content[10]);
}
string fileName;
using (var fileSystemPageManager = new FileSystemPageManager(4096))
using (var storage = new Storage(fileSystemPageManager))
using (var recoveryFile = new RecoveryFile(fileSystemPageManager, fileSystemPageManager.PageSize))
{
storage.OpenOrCreate(StoragePath);
var page = fileSystemPageManager.FetchPage(index);
index = page.Index;
page.Content[10] = 0xaf;
fileSystemPageManager.RemovePage(index);
var resurrectedPage = fileSystemPageManager.CreatePage();
resurrectIndex = resurrectedPage.Index;
//check we're not going wrong way
Assert.AreEqual(index, resurrectIndex);
resurrectedPage.Content[10] = 0xff;
Assert.AreNotEqual(0xff, page.Content[10]);
fileSystemPageManager.Dispose();
recoveryFile.WriteUpdatePageRecord(page);
recoveryFile.WriteDeletePageRecord(index);
recoveryFile.WriteUpdatePageRecord(resurrectedPage);
recoveryFile.WriteFinalMarker();
fileName = recoveryFile.FileName;
}
Assert.True(File.Exists(fileName));
Assert.GreaterOrEqual(new FileInfo(fileName).Length, 1);
using (var manager = new FileSystemPageManager(4096))
using (var storage = new Storage(manager))
{
storage.OpenOrCreate(StoragePath);
var page = manager.FetchPage(index);
Assert.AreEqual(resurrectIndex, page.Index);
Assert.AreEqual(0xff, page.Content[10]);
}
}