internal static int Allocate(StorageImpl db, int root, int type, BtreeKey ins)
{
int pageId = db.AllocatePage();
Page pg = db.PutPage(pageId);
SetItemsCount(pg, 1);
if (type == ClassDescriptor.tpString)
{
char[] sval = (char[]) ins.key.oval;
int len = sval.Length;
SetSize(pg, len * 2);
SetKeyStrOffs(pg, 0, keySpace - len * 2);
SetKeyStrSize(pg, 0, len);
SetKeyStrOid(pg, 0, ins.oid);
SetKeyStrOid(pg, 1, root);
SetKeyStrChars(pg, keySpace - len * 2, sval);
}
else if (type == ClassDescriptor.tpArrayOfByte)
{
byte[] bval = (byte[]) ins.key.oval;
int len = bval.Length;
SetSize(pg, len);
SetKeyStrOffs(pg, 0, keySpace - len);
SetKeyStrSize(pg, 0, len);
SetKeyStrOid(pg, 0, ins.oid);
SetKeyStrOid(pg, 1, root);
SetKeyBytes(pg, keySpace - len, bval);
}
else
{
ins.Pack(pg, 0);
SetReference(pg, maxItems - 2, root);
}
db.pool.Unfix(pg);
return pageId;
}
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);
}
}
}