/// <summary> /// Releases db item by its reference /// </summary> /// <param name="reference">Reference to item to release</param> public void Free(DbItemReference reference) { IPage page = _pageManager.FetchPage(reference.PageIndex); var header = PageFormatter.GetPageHeader(page); if (header.SizeRange == SizeRange.MultiPage) { while (page != null) { _pageManager.RemovePage(page.Index); var nextPageIndex = ((MultipageItemPageHeader)PageFormatter.GetPageHeader(page)).NextPageIndex; page = nextPageIndex == -1 ? null : _pageManager.FetchPage(nextPageIndex); } } else { if (PageFormatter.ReadFixedSizeItemsCount(page) == 1) { _pageManager.RemovePage(page.Index); _fsm.Set(page.Index, FsmValue.Full); } else { PageFormatter.DeleteFixedSizeItem(page, reference.ItemIndex); _pageManager.UpdatePage(page); _fsm.Set(page.Index, EnumHelper.FsmValueFromSizeRange(header.SizeRange)); } } }
public void FixedSizeItemsPage() { int pageSize = 32768; var dummyPageManager = new FileSystemPageManager(pageSize); var p = new Page(dummyPageManager, 0, new byte[pageSize]); var header = new FixedSizeItemsPageHeader(); var r = new Random(); foreach (var sizeRange in EnumHelper.FixedSizeItemsSizeRanges()) { header.SizeRange = sizeRange; PageFormatter.InitPage(p, header); var item = new DbItem(new byte[DbItem.GetMaxSize(header.SizeRange)]); r.NextBytes(item.RawData); // fill the page with the items short count = 0; bool spaceRemains = true; while (PageFormatter.HasFreeSpaceForFixedSizeItem(p)) { Assert.IsTrue(spaceRemains); PageFormatter.AddFixedSizeItem(p, item, out spaceRemains); count++; Assert.AreEqual(count, PageFormatter.ReadFixedSizeItemsCount(p)); } Assert.IsFalse(spaceRemains); // check if fetched objects are equal to originals for (short j = 0; j < PageFormatter.ReadFixedSizeItemsCount(p); j++) { DbItem readItem = PageFormatter.ReadFixedSizeItem(p, j); Assert.IsTrue(AreEqualByteArrays(item.RawData, readItem.RawData)); } // delete all added items short itemindex = 0; while (PageFormatter.ReadFixedSizeItemsCount(p) > 0) { PageFormatter.DeleteFixedSizeItem(p, itemindex); count--; itemindex++; Assert.AreEqual(count, PageFormatter.ReadFixedSizeItemsCount(p)); } } }