private void Init()
{
IPage headingPage = _pageManager.FetchPage(0);
var header = PageFormatter.GetPageHeader(headingPage) as HeadingPageHeader;
if (header == null)
{
throw new StorageFormatException("Heading page not found");
}
_firstFsmPageIndex = header.FsmPageIndex;
_fsmPageIndexes.Add(_firstFsmPageIndex);
IPage firstFsmPage = _pageManager.FetchPage(_firstFsmPageIndex);
var fsmHeader = PageFormatter.GetPageHeader(firstFsmPage) as FreeSpaceMapPageHeader;
if (fsmHeader == null)
{
throw new StorageFormatException("Free space map page not found");
}
_entryPerPage = PageFormatter.GetFsmEntryCount(firstFsmPage);
_isInitialized = true;
}
public void OnEmptyStorageAllRequestedPagesShouldBeFull()
{
var manager = new FileSystemPageManager(4096);
using (var storage = new Storage(manager))
{
storage.CreateNew(StoragePath);
var fsm = new FreeSpaceMap(manager);
int entryCount = PageFormatter.GetFsmEntryCount(manager.FetchPage(1));
for (int i = 0; i < entryCount; i++)
{
Assert.AreEqual(FsmValue.Full, fsm.Get(i));
}
}
}
public void MultiPageOperations()
{
var manager = new FileSystemPageManager(4096);
using (var storage = new Storage(manager))
{
storage.CreateNew(StoragePath);
var fsm = new FreeSpaceMap(manager);
int entryPerPage = PageFormatter.GetFsmEntryCount(manager.FetchPage(1));
int entryCount = entryPerPage * 3;
// check writing to the last page
var value = FsmValue.Class0;
var index = entryCount - 1;
fsm.Set(index, value);
Assert.AreEqual(value, fsm.Get(index));
// middle page
value = FsmValue.Class1;
index = entryPerPage + 1;
fsm.Set(index, value);
Assert.AreEqual(value, fsm.Get(index));
// the first page
value = FsmValue.Class2;
index = entryPerPage - 1;
fsm.Set(index, value);
Assert.AreEqual(value, fsm.Get(index));
for (int i = 0; i < entryCount; i++)
{
fsm.Set(i, FsmValue.Class3);
}
for (int i = 0; i < entryCount; i++)
{
long pageIndex = fsm.GetFreePageIndex(FsmValue.Class3);
Assert.AreNotEqual(-1, pageIndex);
fsm.Set(i, FsmValue.Full);
}
}
}
public void SinglePageOperations()
{
var manager = new FileSystemPageManager(4096);
using (var storage = new Storage(manager))
{
storage.CreateNew(StoragePath);
var fsm = new FreeSpaceMap(manager);
var r = new Random();
int entryCount = PageFormatter.GetFsmEntryCount(manager.FetchPage(1));
for (int i = 0; i < 100000; i++)
{
var value = (FsmValue)r.Next((int)FsmValue.Max);
var index = r.Next(entryCount);
fsm.Set(index, value);
Assert.AreEqual(value, fsm.Get(index));
}
}
}
public void FsmPage()
{
int pageSize = 32768;
var dummyPageManager = new FileSystemPageManager(pageSize);
var p = new Page(dummyPageManager, 0, new byte[pageSize]);
var fsmh = new FreeSpaceMapPageHeader();
var r = new Random();
PageFormatter.InitPage(p, fsmh);
int fsmEntryCount = PageFormatter.GetFsmEntryCount(p);
// set all values to "full"
PageFormatter.SetAllFsmValues(p, FsmValue.Full);
// check if all values are actually "full"
for (int i = 0; i < fsmEntryCount; i++)
{
Assert.AreEqual(FsmValue.Full, PageFormatter.GetFsmValue(p, i));
}
var values = new FsmValue[fsmEntryCount];
// set and keep random values
for (int i = 0; i < fsmEntryCount; i++)
{
var value = (byte)r.Next((byte)FsmValue.Full + 1);
PageFormatter.SetFsmValue(p, i, (FsmValue)value);
values[i] = (FsmValue)value;
}
// compare it
for (int i = 0; i < fsmEntryCount; i++)
{
Assert.AreEqual(values[i], PageFormatter.GetFsmValue(p, i));
}
}
