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);
}
}
}
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;
}
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);
}
}
}
