Exemplo n.º 1
0
        internal static int Remove(StorageImpl db, int pageId, Btree tree, BtreeKey rem, int height)
        {
            Page pg = db.GetPage(pageId);
            try
            {
                int i, n = GetItemsCount(pg), l = 0, r = n;

                if (tree.type == ClassDescriptor.tpString)
                {
                    while (l < r)
                    {
                        i = (l + r) >> 1;
                        if (CompareStr(rem.key, pg, i) > 0)
                        {
                            l = i + 1;
                        }
                        else
                        {
                            r = i;
                        }
                    }
                    if (--height != 0)
                    {
                        do
                        {
                            switch (Remove(db, GetKeyStrOid(pg, r), tree, rem, height))
                            {
                                case Btree.op_underflow:
                                    db.pool.Unfix(pg);
                                    pg = null;
                                    pg = db.PutPage(pageId);
                                    return HandlePageUnderflow(db, pg, r, tree.type, rem, height);

                                case Btree.op_done:
                                    return Btree.op_done;

                                case Btree.op_overflow:
                                    db.pool.Unfix(pg);
                                    pg = null;
                                    pg = db.PutPage(pageId);
                                    return InsertStrKey(db, pg, r, rem, height);
                                }
                        }
                        while (++r <= n);
                    }
                    else
                    {
                        while (r < n)
                        {
                            if (CompareStr(rem.key, pg, r) == 0)
                            {
                                int oid = GetKeyStrOid(pg, r);
                                if (oid == rem.oid || rem.oid == 0)
                                {
                                    rem.oldOid = oid;
                                    db.pool.Unfix(pg);
                                    pg = null;
                                    pg = db.PutPage(pageId);
                                    return RemoveStrKey(pg, r);
                                }
                            }
                            else
                            {
                                break;
                            }
                            r += 1;
                        }
                    }
                }
                else if (tree.type == ClassDescriptor.tpArrayOfByte)
                {
                    while (l < r)
                    {
                        i = (l + r) >> 1;
                        if (tree.CompareByteArrays(rem.key, pg, i) > 0)
                        {
                            l = i + 1;
                        }
                        else
                        {
                            r = i;
                        }
                    }
                    if (--height != 0)
                    {
                        do
                        {
                            switch (Remove(db, GetKeyStrOid(pg, r), tree, rem, height))
                            {
                                case Btree.op_underflow:
                                    db.pool.Unfix(pg);
                                    pg = null;
                                    pg = db.PutPage(pageId);
                                    return HandlePageUnderflow(db, pg, r, tree.type, rem, height);

                                case Btree.op_done:
                                    return Btree.op_done;

                                case Btree.op_overflow:
                                    db.pool.Unfix(pg);
                                    pg = null;
                                    pg = db.PutPage(pageId);
                                    return InsertByteArrayKey(db, pg, r, rem, height);
                                }
                        }
                        while (++r <= n);
                    }
                    else
                    {
                        while (r < n)
                        {
                            if (tree.CompareByteArrays(rem.key, pg, r) == 0)
                            {
                                int oid = GetKeyStrOid(pg, r);
                                if (oid == rem.oid || rem.oid == 0)
                                {
                                    rem.oldOid = oid;
                                    db.pool.Unfix(pg);
                                    pg = null;
                                    pg = db.PutPage(pageId);
                                    return RemoveByteArrayKey(pg, r);
                                }
                            }
                            else
                            {
                                break;
                            }
                            r += 1;
                        }
                    }
                }
                else
                {
                    // scalar types
                    int itemSize = ClassDescriptor.Sizeof[tree.type];
                    while (l < r)
                    {
                        i = (l + r) >> 1;
                        if (Compare(rem.key, pg, i) > 0)
                        {
                            l = i + 1;
                        }
                        else
                        {
                            r = i;
                        }
                    }
                    if (--height == 0)
                    {
                        int oid = rem.oid;
                        while (r < n)
                        {
                            if (Compare(rem.key, pg, r) == 0)
                            {
                                if (GetReference(pg, maxItems - r - 1) == oid || oid == 0)
                                {
                                    rem.oldOid = GetReference(pg, maxItems - r - 1);
                                    db.pool.Unfix(pg);
                                    pg = null;
                                    pg = db.PutPage(pageId);
                                    MemCopy(pg, r, pg, r + 1, n - r - 1, itemSize);
                                    MemCopy(pg, maxItems - n + 1, pg, maxItems - n, n - r - 1, 4);
                                    SetItemsCount(pg, --n);
                                    return n * (itemSize + 4) < keySpace / 2 ? Btree.op_underflow : Btree.op_done;
                                }
                            }
                            else
                            {
                                break;
                            }
                            r += 1;
                        }
                        return Btree.op_not_found;
                    }
                    do
                    {
                        switch (Remove(db, GetReference(pg, maxItems - r - 1), tree, rem, height))
                        {
                            case Btree.op_underflow:
                                db.pool.Unfix(pg);
                                pg = null;
                                pg = db.PutPage(pageId);
                                return HandlePageUnderflow(db, pg, r, tree.type, rem, height);

                            case Btree.op_done:
                                return Btree.op_done;
                            }
                    }
                    while (++r <= n);
                }
                return Btree.op_not_found;
            }
            finally
            {
                if (pg != null)
                {
                    db.pool.Unfix(pg);
                }
            }
        }
Exemplo n.º 2
0
 internal static bool Find(StorageImpl db, int pageId, Key firstKey, Key lastKey, Btree tree, int height, ArrayList result)
 {
     Page pg = db.GetPage(pageId);
     int l = 0, n = GetItemsCount(pg), r = n;
     int oid;
     height -= 1;
     try
     {
         if (tree.type == ClassDescriptor.tpString)
         {
             if (firstKey != null)
             {
                 while (l < r)
                 {
                     int i = (l + r) >> 1;
                     if (CompareStr(firstKey, pg, i) >= firstKey.inclusion)
                     {
                         l = i + 1;
                     }
                     else
                     {
                         r = i;
                     }
                 }
                 Assert.That(r == l);
             }
             if (lastKey != null)
             {
                 if (height == 0)
                 {
                     while (l < n)
                     {
                         if (-CompareStr(lastKey, pg, l) >= lastKey.inclusion)
                         {
                             return false;
                         }
                         oid = GetKeyStrOid(pg, l);
                         result.Add(db.LookupObject(oid, null));
                         l += 1;
                     }
                 }
                 else
                 {
                     do
                     {
                         if (!Find(db, GetKeyStrOid(pg, l), firstKey, lastKey, tree, height, result))
                         {
                             return false;
                         }
                         if (l == n)
                         {
                             return true;
                         }
                     }
                     while (CompareStr(lastKey, pg, l++) >= 0);
                     return false;
                 }
             }
             else
             {
                 if (height == 0)
                 {
                     while (l < n)
                     {
                         oid = GetKeyStrOid(pg, l);
                         result.Add(db.LookupObject(oid, null));
                         l += 1;
                     }
                 }
                 else
                 {
                     do
                     {
                         if (!Find(db, GetKeyStrOid(pg, l), firstKey, lastKey, tree, height, result))
                         {
                             return false;
                         }
                     }
                     while (++l <= n);
                 }
             }
         }
         else if (tree.type == ClassDescriptor.tpArrayOfByte)
         {
             if (firstKey != null)
             {
                 while (l < r)
                 {
                     int i = (l + r) >> 1;
                     if (tree.CompareByteArrays(firstKey, pg, i) >= firstKey.inclusion)
                     {
                         l = i + 1;
                     }
                     else
                     {
                         r = i;
                     }
                 }
                 Assert.That(r == l);
             }
             if (lastKey != null)
             {
                 if (height == 0)
                 {
                     while (l < n)
                     {
                         if (-tree.CompareByteArrays(lastKey, pg, l) >= lastKey.inclusion)
                         {
                             return false;
                         }
                         oid = GetKeyStrOid(pg, l);
                         result.Add(db.LookupObject(oid, null));
                         l += 1;
                     }
                 }
                 else
                 {
                     do
                     {
                         if (!Find(db, GetKeyStrOid(pg, l), firstKey, lastKey, tree, height, result))
                         {
                             return false;
                         }
                         if (l == n)
                         {
                             return true;
                         }
                     }
                     while (tree.CompareByteArrays(lastKey, pg, l++) >= 0);
                     return false;
                 }
             }
             else
             {
                 if (height == 0)
                 {
                     while (l < n)
                     {
                         oid = GetKeyStrOid(pg, l);
                         result.Add(db.LookupObject(oid, null));
                         l += 1;
                     }
                 }
                 else
                 {
                     do
                     {
                         if (!Find(db, GetKeyStrOid(pg, l), firstKey, lastKey, tree, height, result))
                         {
                             return false;
                         }
                     }
                     while (++l <= n);
                 }
             }
         }
         else
         {
             if (firstKey != null)
             {
                 while (l < r)
                 {
                     int i = (l + r) >> 1;
                     if (Compare(firstKey, pg, i) >= firstKey.inclusion)
                     {
                         l = i + 1;
                     }
                     else
                     {
                         r = i;
                     }
                 }
                 Assert.That(r == l);
             }
             if (lastKey != null)
             {
                 if (height == 0)
                 {
                     while (l < n)
                     {
                         if (-Compare(lastKey, pg, l) >= lastKey.inclusion)
                         {
                             return false;
                         }
                         oid = GetReference(pg, maxItems - 1 - l);
                         result.Add(db.LookupObject(oid, null));
                         l += 1;
                     }
                     return true;
                 }
                 else
                 {
                     do
                     {
                         if (!Find(db, GetReference(pg, maxItems - 1 - l), firstKey, lastKey, tree, height, result))
                         {
                             return false;
                         }
                         if (l == n)
                         {
                             return true;
                         }
                     }
                     while (Compare(lastKey, pg, l++) >= 0);
                     return false;
                 }
             }
             if (height == 0)
             {
                 while (l < n)
                 {
                     oid = GetReference(pg, maxItems - 1 - l);
                     result.Add(db.LookupObject(oid, null));
                     l += 1;
                 }
             }
             else
             {
                 do
                 {
                     if (!Find(db, GetReference(pg, maxItems - 1 - l), firstKey, lastKey, tree, height, result))
                     {
                         return false;
                     }
                 }
                 while (++l <= n);
             }
         }
     }
     finally
     {
         db.pool.Unfix(pg);
     }
     return true;
 }
Exemplo n.º 3
0
 internal static int Insert(StorageImpl db, int pageId, Btree tree, BtreeKey ins, int height, bool unique, bool overwrite)
 {
     Page pg = db.GetPage(pageId);
     int result;
     int l = 0, n = GetItemsCount(pg), r = n;
     try
     {
         if (tree.type == ClassDescriptor.tpString)
         {
             while (l < r)
             {
                 int i = (l + r) >> 1;
                 if (CompareStr(ins.key, pg, i) > 0)
                 {
                     l = i + 1;
                 }
                 else
                 {
                     r = i;
                 }
             }
             Assert.That(l == r);
             if (--height != 0)
             {
                 result = Insert(db, GetKeyStrOid(pg, r), tree, ins, height, unique, overwrite);
                 Assert.That(result != Btree.op_not_found);
                 if (result != Btree.op_overflow)
                 {
                     return result;
                 }
             }
             else if (r < n && CompareStr(ins.key, pg, r) == 0)
             {
                 if (overwrite)
                 {
                     db.pool.Unfix(pg);
                     pg = null;
                     pg = db.PutPage(pageId);
                     ins.oldOid = GetKeyStrOid(pg, r);
                     SetKeyStrOid(pg, r, ins.oid);
                     return Btree.op_overwrite;
                 }
                 else if (unique)
                 {
                     return Btree.op_duplicate;
                 }
             }
             db.pool.Unfix(pg);
             pg = null;
             pg = db.PutPage(pageId);
             return InsertStrKey(db, pg, r, ins, height);
         }
         else if (tree.type == ClassDescriptor.tpArrayOfByte)
         {
             while (l < r)
             {
                 int i = (l + r) >> 1;
                 if (tree.CompareByteArrays(ins.key, pg, i) > 0)
                 {
                     l = i + 1;
                 }
                 else
                 {
                     r = i;
                 }
             }
             Assert.That(l == r);
             if (--height != 0)
             {
                 result = Insert(db, GetKeyStrOid(pg, r), tree, ins, height, unique, overwrite);
                 Assert.That(result != Btree.op_not_found);
                 if (result != Btree.op_overflow)
                 {
                     return result;
                 }
             }
             else if (r < n && tree.CompareByteArrays(ins.key, pg, r) == 0)
             {
                 if (overwrite)
                 {
                     db.pool.Unfix(pg);
                     pg = null;
                     pg = db.PutPage(pageId);
                     ins.oldOid = GetKeyStrOid(pg, r);
                     SetKeyStrOid(pg, r, ins.oid);
                     return Btree.op_overwrite;
                 }
                 else if (unique)
                 {
                     return Btree.op_duplicate;
                 }
             }
             db.pool.Unfix(pg);
             pg = null;
             pg = db.PutPage(pageId);
             return InsertByteArrayKey(db, pg, r, ins, height);
         }
         else
         {
             while (l < r)
             {
                 int i = (l + r) >> 1;
                 if (Compare(ins.key, pg, i) > 0)
                     l = i + 1;
                 else
                     r = i;
             }
             Assert.That(l == r);
             /* insert before e[r] */
             if (--height != 0)
             {
                 result = Insert(db, GetReference(pg, maxItems - r - 1), tree, ins, height, unique, overwrite);
                 Assert.That(result != Btree.op_not_found);
                 if (result != Btree.op_overflow)
                 {
                     return result;
                 }
                 n += 1;
             }
             else if (r < n && Compare(ins.key, pg, r) == 0)
             {
                 if (overwrite)
                 {
                     db.pool.Unfix(pg);
                     pg = null;
                     pg = db.PutPage(pageId);
                     ins.oldOid = GetReference(pg, maxItems - r - 1);
                     SetReference(pg, maxItems - r - 1, ins.oid);
                     return Btree.op_overwrite;
                 }
                 else if (unique)
                 {
                     return Btree.op_duplicate;
                 }
             }
             db.pool.Unfix(pg);
             pg = null;
             pg = db.PutPage(pageId);
             int itemSize = ClassDescriptor.Sizeof[tree.type];
             int max = keySpace / (4 + itemSize);
             if (n < max)
             {
                 MemCopy(pg, r + 1, pg, r, n - r, itemSize);
                 MemCopy(pg, maxItems - n - 1, pg, maxItems - n, n - r, 4);
                 ins.Pack(pg, r);
                 SetItemsCount(pg, GetItemsCount(pg) + 1);
                 return Btree.op_done;
             }
             else
             {
                 /* page is full then divide page */
                 pageId = db.AllocatePage();
                 Page b = db.PutPage(pageId);
                 Assert.That(n == max);
                 int m = max / 2;
                 if (r < m)
                 {
                     MemCopy(b, 0, pg, 0, r, itemSize);
                     MemCopy(b, r + 1, pg, r, m - r - 1, itemSize);
                     MemCopy(pg, 0, pg, m - 1, max - m + 1, itemSize);
                     MemCopy(b, maxItems - r, pg, maxItems - r, r, 4);
                     ins.Pack(b, r);
                     MemCopy(b, maxItems - m, pg, maxItems - m + 1, m - r - 1, 4);
                     MemCopy(pg, maxItems - max + m - 1, pg, maxItems - max, max - m + 1, 4);
                 }
                 else
                 {
                     MemCopy(b, 0, pg, 0, m, itemSize);
                     MemCopy(pg, 0, pg, m, r - m, itemSize);
                     MemCopy(pg, r - m + 1, pg, r, max - r, itemSize);
                     MemCopy(b, maxItems - m, pg, maxItems - m, m, 4);
                     MemCopy(pg, maxItems - r + m, pg, maxItems - r, r - m, 4);
                     ins.Pack(pg, r - m);
                     MemCopy(pg, maxItems - max + m - 1, pg, maxItems - max, max - r, 4);
                 }
                 ins.oid = pageId;
                 ins.Extract(b, firstKeyOffs + (m - 1) * itemSize, tree.type);
                 if (height == 0)
                 {
                     SetItemsCount(pg, max - m + 1);
                     SetItemsCount(b, m);
                 }
                 else
                 {
                     SetItemsCount(pg, max - m);
                     SetItemsCount(b, m - 1);
                 }
                 db.pool.Unfix(b);
                 return Btree.op_overflow;
             }
         }
     }
     finally
     {
         if (pg != null)
         {
             db.pool.Unfix(pg);
         }
     }
 }