public bool Remove(object obj)
#endif
{
StorageImpl db = (StorageImpl)Storage;
if (db == null)
{
throw new StorageError(StorageError.ErrorCode.DELETED_OBJECT);
}
if (root == 0)
{
return(false);
}
BtreeResult result = BitIndexPage.remove(db, root, db.GetOid(obj), height);
if (result == BtreeResult.NotFound)
{
return(false);
}
nElems -= 1;
if (result == BtreeResult.Underflow)
{
Page pg = db.getPage(root);
if (BitIndexPage.getnItems(pg) == 0)
{
int newRoot = 0;
if (height != 1)
{
newRoot = BitIndexPage.getItem(pg, BitIndexPage.maxItems - 1);
}
db.freePage(root);
root = newRoot;
height -= 1;
}
db.pool.unfix(pg);
}
updateCounter += 1;
Modify();
return(true);
}
internal static BtreeResult handlePageUnderflow(StorageImpl db, Page pg, int r, int height)
{
int nItems = getnItems(pg);
Page a = db.putPage(getItem(pg, maxItems - r - 1));
int an = getnItems(a);
if (r < nItems)
{ // exists greater page
Page b = db.getPage(getItem(pg, maxItems - r - 2));
int bn = getnItems(b);
Debug.Assert(bn >= an);
if (height != 1)
{
memcpy(a, an, pg, r, 1);
an += 1;
bn += 1;
}
if (an + bn > max)
{
// reallocation of nodes between pages a and b
int i = bn - ((an + bn) >> 1);
db.pool.unfix(b);
b = db.putPage(getItem(pg, maxItems - r - 2));
memcpy(a, an, b, 0, i);
memcpy(b, 0, b, i, bn - i);
memcpy(a, maxItems - an - i, b, maxItems - i, i);
memcpy(b, maxItems - bn + i, b, maxItems - bn, bn - i);
if (height != 1)
{
memcpy(pg, r, a, an + i - 1, 1);
}
else
{
memcpy(pg, r, a, maxItems - an - i, 1);
}
setnItems(b, getnItems(b) - i);
setnItems(a, getnItems(a) + i);
db.pool.unfix(a);
db.pool.unfix(b);
return(BtreeResult.Done);
}
else
{ // merge page b to a
memcpy(a, an, b, 0, bn);
memcpy(a, maxItems - an - bn, b, maxItems - bn, bn);
db.freePage(getItem(pg, maxItems - r - 2));
memcpy(pg, maxItems - nItems, pg, maxItems - nItems - 1,
nItems - r - 1);
memcpy(pg, r, pg, r + 1, nItems - r - 1);
setnItems(a, getnItems(a) + bn);
setnItems(pg, nItems - 1);
db.pool.unfix(a);
db.pool.unfix(b);
return(nItems < max / 3 ? BtreeResult.Underflow : BtreeResult.Done);
}
}
else
{ // page b is before a
Page b = db.getPage(getItem(pg, maxItems - r));
int bn = getnItems(b);
Debug.Assert(bn >= an);
if (height != 1)
{
an += 1;
bn += 1;
}
if (an + bn > max)
{
// reallocation of nodes between pages a and b
int i = bn - ((an + bn) >> 1);
db.pool.unfix(b);
b = db.putPage(getItem(pg, maxItems - r));
memcpy(a, i, a, 0, an);
memcpy(a, 0, b, bn - i, i);
memcpy(a, maxItems - an - i, a, maxItems - an, an);
memcpy(a, maxItems - i, b, maxItems - bn, i);
if (height != 1)
{
memcpy(a, i - 1, pg, r - 1, 1);
memcpy(pg, r - 1, b, bn - i - 1, 1);
}
else
{
memcpy(pg, r - 1, b, maxItems - bn + i, 1);
}
setnItems(b, getnItems(b) - i);
setnItems(a, getnItems(a) + i);
db.pool.unfix(a);
db.pool.unfix(b);
return(BtreeResult.Done);
}
else
{ // merge page b to a
memcpy(a, bn, a, 0, an);
memcpy(a, 0, b, 0, bn);
memcpy(a, maxItems - an - bn, a, maxItems - an, an);
memcpy(a, maxItems - bn, b, maxItems - bn, bn);
if (height != 1)
{
memcpy(a, bn - 1, pg, r - 1, 1);
}
db.freePage(getItem(pg, maxItems - r));
setItem(pg, maxItems - r, getItem(pg, maxItems - r - 1));
setnItems(a, getnItems(a) + bn);
setnItems(pg, nItems - 1);
db.pool.unfix(a);
db.pool.unfix(b);
return(nItems < max / 3 ? BtreeResult.Underflow : BtreeResult.Done);
}
}
}
internal static void purge(StorageImpl db, int pageId, ClassDescriptor.FieldType type, int height)
{
if (--height != 0)
{
Page pg = db.getPage(pageId);
int n = getnItems(pg) + 1;
if (type == ClassDescriptor.FieldType.tpString || type == ClassDescriptor.FieldType.tpArrayOfByte)
{
// page of strings
while (--n >= 0)
{
purge(db, getKeyStrOid(pg, n), type, height);
}
}
else
{
while (--n >= 0)
{
purge(db, getReference(pg, maxItems - n - 1), type, height);
}
}
db.pool.unfix(pg);
}
db.freePage(pageId);
}
internal static BtreeResult handlePageUnderflow(StorageImpl db, Page pg, int r, ClassDescriptor.FieldType type, BtreeKey rem, int height)
{
int nItems = getnItems(pg);
if (type == ClassDescriptor.FieldType.tpString)
{
Page a = db.putPage(getKeyStrOid(pg, r));
int an = getnItems(a);
if (r < nItems)
{
// exists greater page
Page b = db.getPage(getKeyStrOid(pg, r + 1));
int bn = getnItems(b);
int merged_size = (an + bn) * strKeySize + getSize(a) + getSize(b);
if (height != 1)
{
merged_size += getKeyStrSize(pg, r) * 2 + strKeySize * 2;
}
if (merged_size > keySpace)
{
// reallocation of nodes between pages a and b
int i, j, k;
db.pool.unfix(b);
b = db.putPage(getKeyStrOid(pg, r + 1));
int size_a = getSize(a);
int size_b = getSize(b);
int addSize, subSize;
if (height != 1)
{
addSize = getKeyStrSize(pg, r);
subSize = getKeyStrSize(b, 0);
}
else
{
addSize = subSize = getKeyStrSize(b, 0);
}
i = 0;
int prevDelta = (an * strKeySize + size_a) - (bn * strKeySize + size_b);
while (true)
{
i += 1;
int delta = ((an + i) * strKeySize + size_a + addSize * 2) - ((bn - i) * strKeySize + size_b - subSize * 2);
if (delta >= 0)
{
if (delta >= - prevDelta)
{
i -= 1;
}
break;
}
size_a += addSize * 2;
size_b -= subSize * 2;
prevDelta = delta;
if (height != 1)
{
addSize = subSize;
subSize = getKeyStrSize(b, i);
}
else
{
addSize = subSize = getKeyStrSize(b, i);
}
}
BtreeResult result = BtreeResult.Done;
if (i > 0)
{
k = i;
if (height != 1)
{
int len = getKeyStrSize(pg, r);
setSize(a, getSize(a) + len * 2);
setKeyStrOffs(a, an, keySpace - getSize(a));
setKeyStrSize(a, an, len);
memcpy(a, getKeyStrOffs(a, an), pg, getKeyStrOffs(pg, r), len * 2, 1);
k -= 1;
an += 1;
setKeyStrOid(a, an + k, getKeyStrOid(b, k));
setSize(b, getSize(b) - getKeyStrSize(b, k) * 2);
}
for (j = 0; j < k; j++)
{
int len = getKeyStrSize(b, j);
setSize(a, getSize(a) + len * 2);
setSize(b, getSize(b) - len * 2);
setKeyStrOffs(a, an, keySpace - getSize(a));
setKeyStrSize(a, an, len);
setKeyStrOid(a, an, getKeyStrOid(b, j));
memcpy(a, getKeyStrOffs(a, an), b, getKeyStrOffs(b, j), len * 2, 1);
an += 1;
}
rem.getStr(b, i - 1);
result = replaceStrKey(db, pg, r, rem, height);
setnItems(a, an);
setnItems(b, compactifyStrings(b, i));
}
db.pool.unfix(a);
db.pool.unfix(b);
return result;
}
else
{
// merge page b to a
if (height != 1)
{
int r_len = getKeyStrSize(pg, r);
setKeyStrSize(a, an, r_len);
setSize(a, getSize(a) + r_len * 2);
setKeyStrOffs(a, an, keySpace - getSize(a));
memcpy(a, getKeyStrOffs(a, an), pg, getKeyStrOffs(pg, r), r_len * 2, 1);
an += 1;
setKeyStrOid(a, an + bn, getKeyStrOid(b, bn));
}
for (int i = 0; i < bn; i++, an++)
{
setKeyStrSize(a, an, getKeyStrSize(b, i));
setKeyStrOffs(a, an, getKeyStrOffs(b, i) - getSize(a));
setKeyStrOid(a, an, getKeyStrOid(b, i));
}
setSize(a, getSize(a) + getSize(b));
setnItems(a, an);
memcpy(a, keySpace - getSize(a), b, keySpace - getSize(b), getSize(b), 1);
db.pool.unfix(a);
db.pool.unfix(b);
db.freePage(getKeyStrOid(pg, r + 1));
setKeyStrOid(pg, r + 1, getKeyStrOid(pg, r));
return removeStrKey(pg, r);
}
}
else
{
// page b is before a
Page b = db.getPage(getKeyStrOid(pg, r - 1));
int bn = getnItems(b);
int merged_size = (an + bn) * strKeySize + getSize(a) + getSize(b);
if (height != 1)
{
merged_size += getKeyStrSize(pg, r - 1) * 2 + strKeySize * 2;
}
if (merged_size > keySpace)
{
// reallocation of nodes between pages a and b
int i, j, k, len;
db.pool.unfix(b);
b = db.putPage(getKeyStrOid(pg, r - 1));
int size_a = getSize(a);
int size_b = getSize(b);
int addSize, subSize;
if (height != 1)
{
addSize = getKeyStrSize(pg, r - 1);
subSize = getKeyStrSize(b, bn - 1);
}
else
{
addSize = subSize = getKeyStrSize(b, bn - 1);
}
i = 0;
int prevDelta = (an * strKeySize + size_a) - (bn * strKeySize + size_b);
while (true)
{
i += 1;
int delta = ((an + i) * strKeySize + size_a + addSize * 2) - ((bn - i) * strKeySize + size_b - subSize * 2);
if (delta >= 0)
{
if (delta >= - prevDelta)
{
i -= 1;
}
break;
}
prevDelta = delta;
size_a += addSize * 2;
size_b -= subSize * 2;
if (height != 1)
{
addSize = subSize;
subSize = getKeyStrSize(b, bn - i - 1);
}
else
{
addSize = subSize = getKeyStrSize(b, bn - i - 1);
}
}
BtreeResult result = BtreeResult.Done;
if (i > 0)
{
k = i;
Debug.Assert(i < bn);
if (height != 1)
{
setSize(b, getSize(b) - getKeyStrSize(b, bn - k) * 2);
memcpy(a, i, a, 0, an + 1, strKeySize);
k -= 1;
setKeyStrOid(a, k, getKeyStrOid(b, bn));
len = getKeyStrSize(pg, r - 1);
setKeyStrSize(a, k, len);
setSize(a, getSize(a) + len * 2);
setKeyStrOffs(a, k, keySpace - getSize(a));
memcpy(a, getKeyStrOffs(a, k), pg, getKeyStrOffs(pg, r - 1), len * 2, 1);
}
else
{
memcpy(a, i, a, 0, an, strKeySize);
}
for (j = 0; j < k; j++)
{
len = getKeyStrSize(b, bn - k + j);
setSize(a, getSize(a) + len * 2);
setSize(b, getSize(b) - len * 2);
setKeyStrOffs(a, j, keySpace - getSize(a));
setKeyStrSize(a, j, len);
setKeyStrOid(a, j, getKeyStrOid(b, bn - k + j));
memcpy(a, getKeyStrOffs(a, j), b, getKeyStrOffs(b, bn - k + j), len * 2, 1);
}
an += i;
setnItems(a, an);
rem.getStr(b, bn - k - 1);
result = replaceStrKey(db, pg, r - 1, rem, height);
setnItems(b, compactifyStrings(b, - i));
}
db.pool.unfix(a);
db.pool.unfix(b);
return result;
}
else
{
// merge page b to a
if (height != 1)
{
memcpy(a, bn + 1, a, 0, an + 1, strKeySize);
int len = getKeyStrSize(pg, r - 1);
setKeyStrSize(a, bn, len);
setSize(a, getSize(a) + len * 2);
setKeyStrOffs(a, bn, keySpace - getSize(a));
setKeyStrOid(a, bn, getKeyStrOid(b, bn));
memcpy(a, getKeyStrOffs(a, bn), pg, getKeyStrOffs(pg, r - 1), len * 2, 1);
an += 1;
}
else
{
memcpy(a, bn, a, 0, an, strKeySize);
}
for (int i = 0; i < bn; i++)
{
setKeyStrOid(a, i, getKeyStrOid(b, i));
setKeyStrSize(a, i, getKeyStrSize(b, i));
setKeyStrOffs(a, i, getKeyStrOffs(b, i) - getSize(a));
}
an += bn;
setnItems(a, an);
setSize(a, getSize(a) + getSize(b));
memcpy(a, keySpace - getSize(a), b, keySpace - getSize(b), getSize(b), 1);
db.pool.unfix(a);
db.pool.unfix(b);
db.freePage(getKeyStrOid(pg, r - 1));
return removeStrKey(pg, r - 1);
}
}
}
else if (type == ClassDescriptor.FieldType.tpArrayOfByte)
{
Page a = db.putPage(getKeyStrOid(pg, r));
int an = getnItems(a);
if (r < nItems)
{
// exists greater page
Page b = db.getPage(getKeyStrOid(pg, r + 1));
int bn = getnItems(b);
int merged_size = (an + bn) * strKeySize + getSize(a) + getSize(b);
if (height != 1)
{
merged_size += getKeyStrSize(pg, r) + strKeySize * 2;
}
if (merged_size > keySpace)
{
// reallocation of nodes between pages a and b
int i, j, k;
db.pool.unfix(b);
b = db.putPage(getKeyStrOid(pg, r + 1));
int size_a = getSize(a);
int size_b = getSize(b);
int addSize, subSize;
if (height != 1)
{
addSize = getKeyStrSize(pg, r);
subSize = getKeyStrSize(b, 0);
}
else
{
addSize = subSize = getKeyStrSize(b, 0);
}
i = 0;
int prevDelta = (an * strKeySize + size_a) - (bn * strKeySize + size_b);
while (true)
{
i += 1;
int delta = ((an + i) * strKeySize + size_a + addSize) - ((bn - i) * strKeySize + size_b - subSize);
if (delta >= 0)
{
if (delta >= - prevDelta)
{
i -= 1;
}
break;
}
size_a += addSize;
size_b -= subSize;
prevDelta = delta;
if (height != 1)
{
addSize = subSize;
subSize = getKeyStrSize(b, i);
}
else
{
addSize = subSize = getKeyStrSize(b, i);
}
}
BtreeResult result = BtreeResult.Done;
if (i > 0)
{
k = i;
if (height != 1)
{
int len = getKeyStrSize(pg, r);
setSize(a, getSize(a) + len);
setKeyStrOffs(a, an, keySpace - getSize(a));
setKeyStrSize(a, an, len);
memcpy(a, getKeyStrOffs(a, an), pg, getKeyStrOffs(pg, r), len, 1);
k -= 1;
an += 1;
setKeyStrOid(a, an + k, getKeyStrOid(b, k));
setSize(b, getSize(b) - getKeyStrSize(b, k));
}
for (j = 0; j < k; j++)
{
int len = getKeyStrSize(b, j);
setSize(a, getSize(a) + len);
setSize(b, getSize(b) - len);
setKeyStrOffs(a, an, keySpace - getSize(a));
setKeyStrSize(a, an, len);
setKeyStrOid(a, an, getKeyStrOid(b, j));
memcpy(a, getKeyStrOffs(a, an), b, getKeyStrOffs(b, j), len, 1);
an += 1;
}
rem.getByteArray(b, i - 1);
result = replaceByteArrayKey(db, pg, r, rem, height);
setnItems(a, an);
setnItems(b, compactifyByteArrays(b, i));
}
db.pool.unfix(a);
db.pool.unfix(b);
return result;
}
else
{
// merge page b to a
if (height != 1)
{
int r_len = getKeyStrSize(pg, r);
setKeyStrSize(a, an, r_len);
setSize(a, getSize(a) + r_len);
setKeyStrOffs(a, an, keySpace - getSize(a));
memcpy(a, getKeyStrOffs(a, an), pg, getKeyStrOffs(pg, r), r_len, 1);
an += 1;
setKeyStrOid(a, an + bn, getKeyStrOid(b, bn));
}
for (int i = 0; i < bn; i++, an++)
{
setKeyStrSize(a, an, getKeyStrSize(b, i));
setKeyStrOffs(a, an, getKeyStrOffs(b, i) - getSize(a));
setKeyStrOid(a, an, getKeyStrOid(b, i));
}
setSize(a, getSize(a) + getSize(b));
setnItems(a, an);
memcpy(a, keySpace - getSize(a), b, keySpace - getSize(b), getSize(b), 1);
db.pool.unfix(a);
db.pool.unfix(b);
db.freePage(getKeyStrOid(pg, r + 1));
setKeyStrOid(pg, r + 1, getKeyStrOid(pg, r));
return removeByteArrayKey(pg, r);
}
}
else
{
// page b is before a
Page b = db.getPage(getKeyStrOid(pg, r - 1));
int bn = getnItems(b);
int merged_size = (an + bn) * strKeySize + getSize(a) + getSize(b);
if (height != 1)
{
merged_size += getKeyStrSize(pg, r - 1) + strKeySize * 2;
}
if (merged_size > keySpace)
{
// reallocation of nodes between pages a and b
int i, j, k, len;
db.pool.unfix(b);
b = db.putPage(getKeyStrOid(pg, r - 1));
int size_a = getSize(a);
int size_b = getSize(b);
int addSize, subSize;
if (height != 1)
{
addSize = getKeyStrSize(pg, r - 1);
subSize = getKeyStrSize(b, bn - 1);
}
else
{
addSize = subSize = getKeyStrSize(b, bn - 1);
}
i = 0;
int prevDelta = (an * strKeySize + size_a) - (bn * strKeySize + size_b);
while (true)
{
i += 1;
int delta = ((an + i) * strKeySize + size_a + addSize) - ((bn - i) * strKeySize + size_b - subSize);
if (delta >= 0)
{
if (delta >= - prevDelta)
{
i -= 1;
}
break;
}
prevDelta = delta;
size_a += addSize;
size_b -= subSize;
if (height != 1)
{
addSize = subSize;
subSize = getKeyStrSize(b, bn - i - 1);
}
else
{
addSize = subSize = getKeyStrSize(b, bn - i - 1);
}
}
BtreeResult result = BtreeResult.Done;
if (i > 0)
{
k = i;
Debug.Assert(i < bn);
if (height != 1)
{
setSize(b, getSize(b) - getKeyStrSize(b, bn - k));
memcpy(a, i, a, 0, an + 1, strKeySize);
k -= 1;
setKeyStrOid(a, k, getKeyStrOid(b, bn));
len = getKeyStrSize(pg, r - 1);
setKeyStrSize(a, k, len);
setSize(a, getSize(a) + len);
setKeyStrOffs(a, k, keySpace - getSize(a));
memcpy(a, getKeyStrOffs(a, k), pg, getKeyStrOffs(pg, r - 1), len, 1);
}
else
{
memcpy(a, i, a, 0, an, strKeySize);
}
for (j = 0; j < k; j++)
{
len = getKeyStrSize(b, bn - k + j);
setSize(a, getSize(a) + len);
setSize(b, getSize(b) - len);
setKeyStrOffs(a, j, keySpace - getSize(a));
setKeyStrSize(a, j, len);
setKeyStrOid(a, j, getKeyStrOid(b, bn - k + j));
memcpy(a, getKeyStrOffs(a, j), b, getKeyStrOffs(b, bn - k + j), len, 1);
}
an += i;
setnItems(a, an);
rem.getByteArray(b, bn - k - 1);
result = replaceByteArrayKey(db, pg, r - 1, rem, height);
setnItems(b, compactifyByteArrays(b, - i));
}
db.pool.unfix(a);
db.pool.unfix(b);
return result;
}
else
{
// merge page b to a
if (height != 1)
{
memcpy(a, bn + 1, a, 0, an + 1, strKeySize);
int len = getKeyStrSize(pg, r - 1);
setKeyStrSize(a, bn, len);
setSize(a, getSize(a) + len);
setKeyStrOffs(a, bn, keySpace - getSize(a));
setKeyStrOid(a, bn, getKeyStrOid(b, bn));
memcpy(a, getKeyStrOffs(a, bn), pg, getKeyStrOffs(pg, r - 1), len, 1);
an += 1;
}
else
{
memcpy(a, bn, a, 0, an, strKeySize);
}
for (int i = 0; i < bn; i++)
{
setKeyStrOid(a, i, getKeyStrOid(b, i));
setKeyStrSize(a, i, getKeyStrSize(b, i));
setKeyStrOffs(a, i, getKeyStrOffs(b, i) - getSize(a));
}
an += bn;
setnItems(a, an);
setSize(a, getSize(a) + getSize(b));
memcpy(a, keySpace - getSize(a), b, keySpace - getSize(b), getSize(b), 1);
db.pool.unfix(a);
db.pool.unfix(b);
db.freePage(getKeyStrOid(pg, r - 1));
return removeByteArrayKey(pg, r - 1);
}
}
}
else
{
Page a = db.putPage(getReference(pg, maxItems - r - 1));
int an = getnItems(a);
int itemSize = ClassDescriptor.Sizeof[(int)type];
if (r < nItems)
{
// exists greater page
Page b = db.getPage(getReference(pg, maxItems - r - 2));
int bn = getnItems(b);
Debug.Assert(bn >= an);
if (height != 1)
{
memcpy(a, an, pg, r, 1, itemSize);
an += 1;
bn += 1;
}
int merged_size = (an + bn) * (4 + itemSize);
if (merged_size > keySpace)
{
// reallocation of nodes between pages a and b
int i = bn - ((an + bn) >> 1);
db.pool.unfix(b);
b = db.putPage(getReference(pg, maxItems - r - 2));
memcpy(a, an, b, 0, i, itemSize);
memcpy(b, 0, b, i, bn - i, itemSize);
memcpy(a, maxItems - an - i, b, maxItems - i, i, 4);
memcpy(b, maxItems - bn + i, b, maxItems - bn, bn - i, 4);
memcpy(pg, r, a, an + i - 1, 1, itemSize);
setnItems(b, getnItems(b) - i);
setnItems(a, getnItems(a) + i);
db.pool.unfix(a);
db.pool.unfix(b);
return BtreeResult.Done;
}
else
{
// merge page b to a
memcpy(a, an, b, 0, bn, itemSize);
memcpy(a, maxItems - an - bn, b, maxItems - bn, bn, 4);
db.freePage(getReference(pg, maxItems - r - 2));
memcpy(pg, maxItems - nItems, pg, maxItems - nItems - 1, nItems - r - 1, 4);
memcpy(pg, r, pg, r + 1, nItems - r - 1, itemSize);
setnItems(a, getnItems(a) + bn);
setnItems(pg, nItems - 1);
db.pool.unfix(a);
db.pool.unfix(b);
return nItems * (itemSize + 4) < keySpace / 3 ? BtreeResult.Underflow : BtreeResult.Done;
}
}
else
{
// page b is before a
Page b = db.getPage(getReference(pg, maxItems - r));
int bn = getnItems(b);
Debug.Assert(bn >= an);
if (height != 1)
{
an += 1;
bn += 1;
}
int merged_size = (an + bn) * (4 + itemSize);
if (merged_size > keySpace)
{
// reallocation of nodes between pages a and b
int i = bn - ((an + bn) >> 1);
db.pool.unfix(b);
b = db.putPage(getReference(pg, maxItems - r));
memcpy(a, i, a, 0, an, itemSize);
memcpy(a, 0, b, bn - i, i, itemSize);
memcpy(a, maxItems - an - i, a, maxItems - an, an, 4);
memcpy(a, maxItems - i, b, maxItems - bn, i, 4);
if (height != 1)
{
memcpy(a, i - 1, pg, r - 1, 1, itemSize);
}
memcpy(pg, r - 1, b, bn - i - 1, 1, itemSize);
setnItems(b, getnItems(b) - i);
setnItems(a, getnItems(a) + i);
db.pool.unfix(a);
db.pool.unfix(b);
return BtreeResult.Done;
}
else
{
// merge page b to a
memcpy(a, bn, a, 0, an, itemSize);
memcpy(a, 0, b, 0, bn, itemSize);
memcpy(a, maxItems - an - bn, a, maxItems - an, an, 4);
memcpy(a, maxItems - bn, b, maxItems - bn, bn, 4);
if (height != 1)
{
memcpy(a, bn - 1, pg, r - 1, 1, itemSize);
}
db.freePage(getReference(pg, maxItems - r));
setReference(pg, maxItems - r, getReference(pg, maxItems - r - 1));
setnItems(a, getnItems(a) + bn);
setnItems(pg, nItems - 1);
db.pool.unfix(a);
db.pool.unfix(b);
return nItems * (itemSize + 4) < keySpace / 3 ? BtreeResult.Underflow : BtreeResult.Done;
}
}
}
}