internal static BtreeResult remove(StorageImpl db, int pageId, Btree tree, BtreeKey rem, int height)
{
Page pg = db.getPage(pageId);
try
{
int i, n = getnItems(pg), l = 0, r = n;
if (tree.FieldType == ClassDescriptor.FieldType.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 BtreeResult.Underflow:
db.pool.unfix(pg);
pg = null;
pg = db.putPage(pageId);
return handlePageUnderflow(db, pg, r, tree.FieldType, rem, height);
case BtreeResult.Done:
return BtreeResult.Done;
case BtreeResult.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.FieldType == ClassDescriptor.FieldType.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 BtreeResult.Underflow:
db.pool.unfix(pg);
pg = null;
pg = db.putPage(pageId);
return handlePageUnderflow(db, pg, r, tree.FieldType, rem, height);
case BtreeResult.Done:
return BtreeResult.Done;
case BtreeResult.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 // scalars
{
int itemSize = ClassDescriptor.Sizeof[(int)tree.FieldType];
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);
memcpy(pg, r, pg, r + 1, n - r - 1, itemSize);
memcpy(pg, maxItems - n + 1, pg, maxItems - n, n - r - 1, 4);
setnItems(pg, --n);
return n * (itemSize + 4) < keySpace / 3 ? BtreeResult.Underflow : BtreeResult.Done;
}
}
else
{
break;
}
r += 1;
}
return BtreeResult.NotFound;
}
do
{
switch (remove(db, getReference(pg, maxItems - r - 1), tree, rem, height))
{
case BtreeResult.Underflow:
db.pool.unfix(pg);
pg = db.putPage(pageId);
return handlePageUnderflow(db, pg, r, tree.FieldType, rem, height);
case BtreeResult.Done:
return BtreeResult.Done;
}
}
while (++r <= n);
}
return BtreeResult.NotFound;
}
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 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 = getnItems(pg), r = n;
int oid;
height -= 1;
try
{
if (tree.FieldType == ClassDescriptor.FieldType.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;
}
}
Debug.Assert(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.FieldType == ClassDescriptor.FieldType.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;
}
}
Debug.Assert(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;
}
}
Debug.Assert(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;
}