internal static int allocate(StorageImpl db, int root, Key ins)
{
int pageId = db.allocatePage();
Page pg = db.putPage(pageId);
setnItems(pg, 1);
setItem(pg, 0, ins.key);
setItem(pg, maxItems - 1, ins.oid);
setItem(pg, maxItems - 2, root);
db.pool.unfix(pg);
return(pageId);
}
internal static BtreeResult insert(StorageImpl db, int pageId, Key ins, int height)
{
Page pg = db.getPage(pageId);
int l = 0, n = getnItems(pg), r = n;
int oid = ins.oid;
try
{
if (--height != 0)
{
while (l < r)
{
int i = (l + r) >> 1;
if (oid > getItem(pg, i))
{
l = i + 1;
}
else
{
r = i;
}
}
Debug.Assert(l == r);
/* insert before e[r] */
BtreeResult result = insert(db, getItem(pg, maxItems - r - 1), ins, height);
Debug.Assert(result != BtreeResult.NotFound);
if (result != BtreeResult.Overflow)
{
return(result);
}
n += 1;
}
else
{
while (l < r)
{
int i = (l + r) >> 1;
if (oid > getItem(pg, maxItems - 1 - i))
{
l = i + 1;
}
else
{
r = i;
}
}
if (r < n && oid == getItem(pg, maxItems - 1 - r))
{
db.pool.unfix(pg);
pg = null;
pg = db.putPage(pageId);
setItem(pg, r, ins.key);
return(BtreeResult.Overwrite);
}
}
db.pool.unfix(pg);
pg = null;
pg = db.putPage(pageId);
if (n < max)
{
memcpy(pg, r + 1, pg, r, n - r);
memcpy(pg, maxItems - n - 1, pg, maxItems - n, n - r);
setItem(pg, r, ins.key);
setItem(pg, maxItems - 1 - r, ins.oid);
setnItems(pg, getnItems(pg) + 1);
return(BtreeResult.Done);
}
else
{ /* page is full then divide page */
pageId = db.allocatePage();
Page b = db.putPage(pageId);
Debug.Assert(n == max);
int m = (max + 1) / 2;
if (r < m)
{
memcpy(b, 0, pg, 0, r);
memcpy(b, r + 1, pg, r, m - r - 1);
memcpy(pg, 0, pg, m - 1, max - m + 1);
memcpy(b, maxItems - r, pg, maxItems - r, r);
setItem(b, r, ins.key);
setItem(b, maxItems - 1 - r, ins.oid);
memcpy(b, maxItems - m, pg, maxItems - m + 1, m - r - 1);
memcpy(pg, maxItems - max + m - 1, pg, maxItems - max, max - m + 1);
}
else
{
memcpy(b, 0, pg, 0, m);
memcpy(pg, 0, pg, m, r - m);
memcpy(pg, r - m + 1, pg, r, max - r);
memcpy(b, maxItems - m, pg, maxItems - m, m);
memcpy(pg, maxItems - r + m, pg, maxItems - r, r - m);
setItem(pg, r - m, ins.key);
setItem(pg, maxItems - 1 - r + m, ins.oid);
memcpy(pg, maxItems - max + m - 1, pg, maxItems - max, max - r);
}
ins.oid = pageId;
if (height == 0)
{
ins.key = getItem(b, maxItems - m);
setnItems(pg, max - m + 1);
setnItems(b, m);
}
else
{
ins.key = getItem(b, m - 1);
setnItems(pg, max - m);
setnItems(b, m - 1);
}
db.pool.unfix(b);
return(BtreeResult.Overflow);
}
}
finally
{
if (pg != null)
{
db.pool.unfix(pg);
}
}
}
internal static BtreeResult insert(StorageImpl db, int pageId, Btree tree, BtreeKey ins, int height, bool unique, bool overwrite)
{
Page pg = db.getPage(pageId);
BtreeResult result;
int l = 0, n = getnItems(pg), r = n;
int ahead = unique ? 1 : 0;
try
{
if (tree.FieldType == ClassDescriptor.FieldType.tpString)
{
while (l < r)
{
int i = (l + r) >> 1;
if (compareStr(ins.key, pg, i) >= ahead)
{
l = i + 1;
}
else
{
r = i;
}
}
Debug.Assert(l == r);
if (--height != 0)
{
result = insert(db, getKeyStrOid(pg, r), tree, ins, height, unique, overwrite);
Debug.Assert(result != BtreeResult.NotFound);
if (result != BtreeResult.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);
setKeyStrOid(pg, r, ins.oid);
return BtreeResult.Overwrite;
}
else if (unique)
{
return BtreeResult.Duplicate;
}
}
db.pool.unfix(pg);
pg = null;
pg = db.putPage(pageId);
return insertStrKey(db, pg, r, ins, height);
}
else if (tree.FieldType == ClassDescriptor.FieldType.tpArrayOfByte)
{
while (l < r)
{
int i = (l + r) >> 1;
if (tree.compareByteArrays(ins.key, pg, i) >= ahead)
{
l = i + 1;
}
else
{
r = i;
}
}
Debug.Assert(l == r);
if (--height != 0)
{
result = insert(db, getKeyStrOid(pg, r), tree, ins, height, unique, overwrite);
Debug.Assert(result != BtreeResult.NotFound);
if (result != BtreeResult.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);
setKeyStrOid(pg, r, ins.oid);
return BtreeResult.Overwrite;
}
else if (unique)
{
return BtreeResult.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) >= ahead)
l = i + 1;
else
r = i;
}
Debug.Assert(l == r);
/* insert before e[r] */
if (--height != 0)
{
result = insert(db, getReference(pg, maxItems - r - 1), tree, ins, height, unique, overwrite);
Debug.Assert(result != BtreeResult.NotFound);
if (result != BtreeResult.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);
setReference(pg, maxItems - r - 1, ins.oid);
return BtreeResult.Overwrite;
}
else if (unique)
{
return BtreeResult.Duplicate;
}
}
db.pool.unfix(pg);
pg = null;
pg = db.putPage(pageId);
int itemSize = ClassDescriptor.Sizeof[(int)tree.FieldType];
int max = keySpace / (4 + itemSize);
if (n < max)
{
memcpy(pg, r + 1, pg, r, n - r, itemSize);
memcpy(pg, maxItems - n - 1, pg, maxItems - n, n - r, 4);
ins.pack(pg, r);
setnItems(pg, getnItems(pg) + 1);
return BtreeResult.Done;
}
else
{
/* page is full then divide page */
pageId = db.allocatePage();
Page b = db.putPage(pageId);
Debug.Assert(n == max);
int m = (max + 1) / 2;
if (r < m)
{
memcpy(b, 0, pg, 0, r, itemSize);
memcpy(b, r + 1, pg, r, m - r - 1, itemSize);
memcpy(pg, 0, pg, m - 1, max - m + 1, itemSize);
memcpy(b, maxItems - r, pg, maxItems - r, r, 4);
ins.pack(b, r);
memcpy(b, maxItems - m, pg, maxItems - m + 1, m - r - 1, 4);
memcpy(pg, maxItems - max + m - 1, pg, maxItems - max, max - m + 1, 4);
}
else
{
memcpy(b, 0, pg, 0, m, itemSize);
memcpy(pg, 0, pg, m, r - m, itemSize);
memcpy(pg, r - m + 1, pg, r, max - r, itemSize);
memcpy(b, maxItems - m, pg, maxItems - m, m, 4);
memcpy(pg, maxItems - r + m, pg, maxItems - r, r - m, 4);
ins.pack(pg, r - m);
memcpy(pg, maxItems - max + m - 1, pg, maxItems - max, max - r, 4);
}
ins.oid = pageId;
ins.extract(b, firstKeyOffs + (m - 1) * itemSize, tree.FieldType);
if (height == 0)
{
setnItems(pg, max - m + 1);
setnItems(b, m);
}
else
{
setnItems(pg, max - m);
setnItems(b, m - 1);
}
db.pool.unfix(b);
return BtreeResult.Overflow;
}
}
}
finally
{
if (pg != null)
{
db.pool.unfix(pg);
}
}
}
internal static BtreeResult insertByteArrayKey(StorageImpl db, Page pg, int r, BtreeKey ins, int height)
{
int nItems = getnItems(pg);
int size = getSize(pg);
int n = (height != 0)?nItems + 1:nItems;
// insert before e[r]
byte[] bval = (byte[])ins.key.oval;
int len = bval.Length;
if (size + len + (n + 1) * strKeySize <= keySpace)
{
memcpy(pg, r + 1, pg, r, n - r, strKeySize);
size += len;
setKeyStrOffs(pg, r, keySpace - size);
setKeyStrSize(pg, r, len);
setKeyStrOid(pg, r, ins.oid);
setKeyBytes(pg, keySpace - size, bval);
nItems += 1;
}
else
{
// page is full then divide page
int pageId = db.allocatePage();
Page b = db.putPage(pageId);
int moved = 0;
int inserted = len + strKeySize;
int prevDelta = (1 << 31) + 1;
for (int bn = 0, i = 0; ; bn += 1)
{
int addSize, subSize;
int j = nItems - i - 1;
int keyLen = getKeyStrSize(pg, i);
if (bn == r)
{
keyLen = len;
inserted = 0;
addSize = len;
if (height == 0)
{
subSize = 0;
j += 1;
}
else
{
subSize = getKeyStrSize(pg, i);
}
}
else
{
addSize = subSize = keyLen;
if (height != 0)
{
if (i + 1 != r)
{
subSize += getKeyStrSize(pg, i + 1);
j -= 1;
}
else
{
inserted = 0;
}
}
}
int delta = (moved + addSize + (bn + 1) * strKeySize) - (j * strKeySize + size - subSize + inserted);
if (delta >= - prevDelta)
{
if (height == 0)
{
ins.getByteArray(b, bn - 1);
}
else
{
Debug.Assert(moved + (bn + 1) * strKeySize <= keySpace, "String fits in the B-Tree page");
if (bn != r)
{
ins.getByteArray(pg, i);
setKeyStrOid(b, bn, getKeyStrOid(pg, i));
size -= keyLen;
i += 1;
}
else
{
setKeyStrOid(b, bn, ins.oid);
}
}
nItems = compactifyByteArrays(pg, i);
if (bn < r || (bn == r && height == 0))
{
memcpy(pg, r - i + 1, pg, r - i, n - r, strKeySize);
size += len;
nItems += 1;
Debug.Assert(size + (n - i + 1) * strKeySize <= keySpace, "String fits in the B-Tree page");
setKeyStrOffs(pg, r - i, keySpace - size);
setKeyStrSize(pg, r - i, len);
setKeyStrOid(pg, r - i, ins.oid);
setKeyBytes(pg, keySpace - size, bval);
}
setnItems(b, bn);
setSize(b, moved);
setSize(pg, size);
setnItems(pg, nItems);
ins.oid = pageId;
db.pool.unfix(b);
return BtreeResult.Overflow;
}
moved += keyLen;
prevDelta = delta;
Debug.Assert(moved + (bn + 1) * strKeySize <= keySpace, "String fits in the B-Tree page");
setKeyStrSize(b, bn, keyLen);
setKeyStrOffs(b, bn, keySpace - moved);
if (bn == r)
{
setKeyStrOid(b, bn, ins.oid);
setKeyBytes(b, keySpace - moved, bval);
}
else
{
setKeyStrOid(b, bn, getKeyStrOid(pg, i));
memcpy(b, keySpace - moved, pg, getKeyStrOffs(pg, i), keyLen, 1);
size -= keyLen;
i += 1;
}
}
}
setnItems(pg, nItems);
setSize(pg, size);
return size + strKeySize * (nItems + 1) < keySpace / 3 ? BtreeResult.Underflow : BtreeResult.Done;
}
internal static int allocate(StorageImpl db, int root, ClassDescriptor.FieldType type, BtreeKey ins)
{
int pageId = db.allocatePage();
Page pg = db.putPage(pageId);
setnItems(pg, 1);
if (type == ClassDescriptor.FieldType.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.FieldType.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;
}