/// <summary>
/// Move para o próximo item.
/// </summary>
/// <returns></returns>
bool IEnumerator.MoveNext()
{
if (_view == null)
{
return(false);
}
_storage._viewManager.OpenView(_view);
if (_area == null)
{
_area = _view.FirstArea();
}
else
{
_area = _area.NextArea();
if (_area == null)
{
_view = _storage._viewManager.GetViewByID(_view.ID + 1);
if (_view != null)
{
_storage._viewManager.OpenView(_view);
_area = _view.FirstArea();
}
}
}
return(_area != null);
}
/// <summary>
/// Calcula a area da memória usada.
/// </summary>
private void CalculateAreaMemoryUsage()
{
MemArea arena = this.FirstArea();
MemArea arena2 = this.FirstArea();
uint capacity = 0;
uint num2 = 0;
while (arena != null)
{
try
{
if (arena.IsFree)
{
num2 += arena.Capacity;
if (arena.Capacity >= capacity)
{
capacity = arena.Capacity;
}
}
arena = arena.NextArea();
if ((arena != null) && (arena.OffsetNext == arena2.Offset))
{
arena.OffsetNext = 0;
}
continue;
}
catch (Exception exception)
{
throw new Exception(exception.Message);
}
}
this.FreeSpace = num2;
this.MaxFreeSpace = capacity;
this.MyFreeSpace = this.FreeSpace + ((uint)MemArea.Header.Size);
}
/// <summary>
/// Desfragmenta.
/// </summary>
/// <returns></returns>
public MemArea DeFragment()
{
MemArea arena2;
MemArea arena = this.FirstArea();
arena2 = arena.NextArea();
while (arena2 != null)
{
if (!arena.IsFree)
{
arena = arena2;
}
else if (arena2.IsFree)
{
arena = MemArea.CoalesceAdjacent(arena2);
}
else
{
MemArea.SwapAdjacent(arena2, arena);
arena = arena2;
}
arena2 = arena.NextArea();
}
this.FreeSpace = arena.Capacity;
this.MaxFreeSpace = arena.Capacity;
this.CalculateAreaMemoryUsage();
return(arena);
}
/// <summary>
/// Divida a <see cref="MemArea"/> em partes com o tamanhon informado.
/// </summary>
/// <param name="area"></param>
/// <param name="size"></param>
/// <returns></returns>
internal static MemArea SplitArea(MemArea area, uint size)
{
uint num = size + ((uint)Header.Size);
if (area.OffsetNext != 0)
{
area.Capacity = area.OffsetNext - (area.Offset + ((uint)Header.Size));
}
if (num > area.Capacity)
{
return(null);
}
uint num2 = (area.Capacity - size) - ((uint)Header.Size);
if (num2 < SPLIT_THRESHOLD)
{
View view1 = area.View;
view1.MyFreeSpace -= area.Capacity + ((uint)Header.Size);
return(area);
}
area.Capacity = size;
MemArea arena2 = area.View.AreaAtOffset(area.Offset + area.TotalLength);
arena2.Capacity = num2;
View view = area.View;
view.MyFreeSpace -= num;
MemArea arenaCopy = area.NextArea();
SetNextArea(arena2, GetActualArea(arenaCopy));
SetNextArea(area, arena2);
return(arena2);
}
/// <summary>
/// Aloca uma <see cref="MemArea"/> com o tamanho informado.
/// </summary>
/// <param name="size"></param>
/// <returns></returns>
public MemArea Allocate(uint size)
{
if (size > this.FreeSpace)
{
return(null);
}
MemArea arena = null;
size = MemArea.Content.RequiredSpace(size);
arena = this.FindFirstFreeArena(size);
if (arena == null)
{
this.CalculateAreaMemoryUsage();
arena = this.DeFragment();
if (arena == null)
{
return(arena);
}
}
MemArea arena2 = MemArea.SplitArea(arena, size);
if (arena2 != null)
{
arena.IsFree = false;
if (arena != arena2)
{
arena2.IsFree = true;
_lastFreeArena = arena2;
}
this.FreeSpace = this.MyFreeSpace - ((uint)MemArea.Header.Size);
this.Usage++;
}
return(arena);
}
/// <summary>
/// Verifica se as areas informadas são adjacentes.
/// </summary>
/// <param name="area1"></param>
/// <param name="area2"></param>
/// <returns></returns>
private static bool AreAdjacent(MemArea area1, MemArea area2)
{
if (area1.OffsetNext != area2.Offset)
{
return(area2.OffsetNext == area1.Offset);
}
return(true);
}
/// <summary>
/// Adquire uma area adjacente.
/// </summary>
/// <param name="area"></param>
/// <returns></returns>
internal static MemArea CoalesceAdjacent(MemArea area)
{
if (area.IsFree)
{
MemArea arenaCopy = area.NextArea();
int num = 0;
if (arenaCopy != null)
{
uint num2 = 0;
while ((arenaCopy != null) && arenaCopy.IsFree)
{
num++;
num2 += arenaCopy.TotalLength;
arenaCopy = arenaCopy.NextArea();
}
if (num2 > 0)
{
area.Capacity += num2;
uint capacity = area.Capacity;
area = SetNextArea(area, GetActualArea(arenaCopy));
area.Capacity = capacity;
}
}
if (area.HasPrevious)
{
uint num4 = 0;
MemArea arena3 = area;
MemArea arena4 = null;
while (true)
{
arena4 = arena3.PreviousArea();
if ((arena4 == null) || !arena4.IsFree)
{
break;
}
num4 += arena4.TotalLength;
arena3 = arena4;
num++;
}
if (num4 > 0)
{
area.Capacity += num4;
uint num5 = area.Capacity;
area.NextArea();
area = SetNextArea(arena3, GetActualArea(arenaCopy));
area.Capacity = num5;
}
}
if (num > 0)
{
View view = area.View;
view.MyFreeSpace += (uint)(num * Header.Size);
}
}
return(area);
}
/// <summary>
/// Define a area anterior.
/// </summary>
/// <param name="arena"></param>
/// <param name="arenaPrev"></param>
/// <returns></returns>
private static MemArea SetPreviousArena(MemArea arena, MemArea arenaPrev)
{
if ((arenaPrev == null) || (arenaPrev != arena))
{
arena.OffsetPrev = (arenaPrev == null) ? 0 : arenaPrev.Offset;
if (arenaPrev != null)
{
arenaPrev.OffsetNext = arena.Offset;
}
}
return(arena);
}
/// <summary>
/// Define a próxima area.
/// </summary>
/// <param name="arena"></param>
/// <param name="arenaNext"></param>
/// <returns></returns>
private static MemArea SetNextArea(MemArea arena, MemArea arenaNext)
{
if ((arenaNext == null) || (arenaNext != arena))
{
arena.OffsetNext = (arenaNext == null) ? 0 : arenaNext.Offset;
if (arenaNext != null)
{
arenaNext.OffsetPrev = arena.Offset;
}
}
return(arena);
}
/// <summary>
/// Recupera a <see cref="MemArea"/> associado com os dados armazenados na <see cref="MemArea"/> informada.
/// </summary>
/// <param name="areaCopy"><see cref="MemArea"/> com os dados do item de armazenamento.</param>
/// <returns></returns>
internal static MemArea GetActualArea(MemArea areaCopy)
{
if (areaCopy == null)
{
return(null);
}
if (!areaCopy.IsFree)
{
StoreItem item = StoreItem.FromBinary(areaCopy.GetMemContents(), areaCopy.View.ParentStorageProvider.CacheContext);
return(areaCopy.View.ParentStorageProvider.GetMemArea(item.Key));
}
return(areaCopy);
}
/// <summary>
/// Recupera o texto que representa a instancia.
/// </summary>
/// <returns></returns>
public override string ToString()
{
StringBuilder builder = new StringBuilder();
builder.Append("View, ID=").Append(this.ID).Append(", maxFree=").Append(this.MaxFreeSpace).Append(", Free=").Append(this.FreeSpace).Append("\r\n");
if (this.IsOpen)
{
for (MemArea arena = this.FirstArea(); arena != null; arena = arena.NextArea())
{
builder.Append(arena.ToString()).Append("\r\n");
}
}
return(builder.ToString());
}
/// <summary>
/// Desaloca a <see cref="MemArea"/> informada.
/// </summary>
/// <param name="area"><see cref="MemArea"/> que será desalocada.</param>
/// <returns></returns>
public MemArea DeAllocate(MemArea area)
{
if (!area.IsFree)
{
uint capacity = area.Capacity;
View view = area.View;
view.MyFreeSpace += area.Capacity;
area.IsFree = true;
area = MemArea.CoalesceAdjacent(area);
area.IsFree = true;
this.FreeSpace = this.MyFreeSpace - ((uint)MemArea.Header.Size);
this.Usage++;
}
return(area);
}
/// <summary>
/// Formata os dados da instancia.
/// </summary>
public void Format()
{
if (this.IsOpen)
{
int size = ViewHeader.Size;
this.Signature = 0xface0ff;
this.FreeSpace = this.MaxFreeSpace = _view.Length - ((uint)size);
this.MyFreeSpace = this.FreeSpace;
_parentStorageProvider = null;
MemArea arena = this.FirstArea();
arena.IsFree = true;
arena.Capacity = (uint)((_view.Length - size) - MemArea.Header.Size);
arena.OffsetNext = 0;
arena.OffsetPrev = 0;
}
}
/// <summary>
/// Adiciona os dados do item na memória.
/// </summary>
/// <param name="item">Buffer com os dados que serão adicionados.</param>
/// <returns>Ponteiro dos dados adicionados.</returns>
public MmfObjectPtr Add(byte[] item)
{
if (item == null)
{
throw new ArgumentNullException("item");
}
if (item.Length > _viewSize)
{
throw new ArgumentException("item size is larger than view size");
}
View matchingView = _viewManager.GetMatchingView((uint)item.Length);
try
{
if (matchingView == null)
{
this.GrowMemoryMappedStore(1);
matchingView = _viewManager.GetMatchingView((uint)item.Length);
}
if (matchingView != null)
{
MemArea area = matchingView.Allocate((uint)item.Length);
if (area == null)
{
return(null);
}
if (!area.SetMemContents(item))
{
matchingView.DeAllocate(area);
return(null);
}
return(new MmfObjectPtr(matchingView, area));
}
}
catch (OutOfMemoryException)
{
throw;
}
catch (Exception)
{
throw;
}
return(null);
}
/// <summary>
/// Define o buffer com o conteúdo.
/// </summary>
/// <param name="value"></param>
/// <returns></returns>
public bool SetMemContents(byte[] value)
{
int num = (int)(this.Capacity - Content.RequiredSpace((uint)value.Length));
if (num < 0)
{
return(false);
}
Content content = new Content();
content.Data = value;
content.RawWrite(this.RawView, (int)this.DataOffset);
if (num > SPLIT_THRESHOLD)
{
MemArea arena = SplitArea(this, Content.RequiredSpace((uint)value.Length));
if (arena != this)
{
arena.IsFree = true;
}
}
return(true);
}
/// <summary>
/// Realiza a troca a <see cref="MemArea"/> adjacente.
/// </summary>
/// <param name="arena1"></param>
/// <param name="arena2"></param>
internal static void SwapAdjacent(MemArea arena1, MemArea arena2)
{
arena1 = GetActualArea(arena1);
arena2 = GetActualArea(arena2);
if (AreAdjacent(arena1, arena2))
{
MemArea arena = arena1;
MemArea arena3 = arena2;
if (arena1.Offset > arena2.Offset)
{
arena = arena2;
arena3 = arena1;
}
Header arenaHeader = arena.AreaHeader;
Header header2 = arena3.AreaHeader;
MemArea arenaCopy = arena3.NextArea();
MemArea actualArena = arena.PreviousArea();
arenaCopy = GetActualArea(arenaCopy);
actualArena = GetActualArea(actualArena);
int count = arena.IsFree ? Header.Size : ((int)arena.TotalLength);
int num2 = arena3.IsFree ? Header.Size : ((int)arena3.TotalLength);
byte[] buffer = arena.RawView.Read((int)arena.Offset, count);
byte[] buffer2 = arena3.RawView.Read((int)arena3.Offset, num2);
arena3._offset = arena.Offset + arena3.TotalLength;
arena.RawView.Write(buffer2, (int)arena.Offset, buffer2.Length);
arena3.RawView.Write(buffer, (int)arena3.Offset, buffer.Length);
arena.IsFree = header2.IsFree;
arena.Capacity = header2.Capacity;
arena.OffsetNext = arena3.Offset;
arena.OffsetPrev = arenaHeader.OffsetPrev;
SetPreviousArena(arena, actualArena);
arena3.IsFree = arenaHeader.IsFree;
arena3.Capacity = arenaHeader.Capacity;
arena3.OffsetNext = header2.OffsetNext;
arena3.OffsetPrev = arena.Offset;
SetNextArea(arena3, arenaCopy);
}
}
/// <summary>
/// Procura pela primeira <see cref="MemArea"/> livre.
/// </summary>
/// <param name="memRequirements">Quantidade de memória requerida.</param>
/// <returns><see cref="MemArea"/> disponível.</returns>
private MemArea FindFirstFreeArena(uint memRequirements)
{
memRequirements += (uint)MemArea.Header.Size;
MemArea arena = this.FirstArea();
if (arena.OffsetNext != 0)
{
arena.Capacity = arena.OffsetNext - (arena.Offset + ((uint)MemArea.Header.Size));
}
if (((_lastFreeArena == null) || !_lastFreeArena.IsFree) || (_lastFreeArena.Capacity < memRequirements))
{
while (arena != null)
{
if (arena.IsFree && (arena.Capacity >= memRequirements))
{
return(arena);
}
arena = arena.NextArea();
}
return(null);
}
return(_lastFreeArena);
}
/// <summary>
/// Construtor padrão.
/// </summary>
/// <param name="storage"></param>
public MmfStorageEnumerator(MmfStorage storage)
{
_storage = storage;
_view = _storage._viewManager.GetViewByID(0);
_area = null;
}
/// <summary>
/// Reseta o enumerado.
/// </summary>
void IEnumerator.Reset()
{
_view = _storage._viewManager.GetViewByID(0);
_area = null;
}
/// <summary>
/// Cria uma instancia já definindo a visão e o bloco da memória.
/// </summary>
/// <param name="v"></param>
/// <param name="block"></param>
public MmfObjectPtr(View v, MemArea block)
{
this.View = v;
this.Area = block;
}
