public KeyValuePair<byte[], byte[]>? MoveToFirstAfter(byte[] key)
{
using(var marshalKey = new MarshalValueStructure(key))
return this.Get(CursorOperation.SetRange, marshalKey.ValueStructure);
}
public KeyValuePair<byte[], byte[]>? MoveToFirstValueAfter(byte[] key, byte[] value)
{
using (var marshalKey = new MarshalValueStructure(key))
using (var marshalValue = new MarshalValueStructure(value))
return this.Get(CursorOperation.GetBothRange, marshalKey.ValueStructure, marshalValue.ValueStructure);
}
public void Put(byte[] key, byte[] value, PutOptions options)
{
using(var keyMarshalStruct = new MarshalValueStructure(key))
using (var valueMarshalStruct = new MarshalValueStructure(value))
{
var keyStruct = keyMarshalStruct.ValueStructure;
var valueStruct = valueMarshalStruct.ValueStructure;
NativeMethods.Execute(lib => lib.mdb_cursor_put(_handle, ref keyStruct, ref valueStruct, options));
}
}
/// <summary>
/// Delete items from a database.
/// This function removes key/data pairs from the database.
/// If the database does not support sorted duplicate data items (MDB_DUPSORT) the data parameter is ignored.
/// If the database supports sorted duplicates and the data parameter is NULL, all of the duplicate data items for the key will be deleted.
/// Otherwise, if the data parameter is non-NULL only the matching data item will be deleted.
/// This function will return MDB_NOTFOUND if the specified key/data pair is not in the database.
/// </summary>
/// <param name="db">A database handle returned by mdb_dbi_open()</param>
/// <param name="key">The key to delete from the database</param>
/// <param name="value">The data to delete (optional)</param>
public void Delete(LightningDatabase db, byte[] key, byte[] value = null)
{
if (db == null)
throw new ArgumentNullException("db");
using (var keyMarshalStruct = new MarshalValueStructure(key))
{
var keyStructure = keyMarshalStruct.ValueStructure;
if (value != null)
{
using (var valueMarshalStruct = new MarshalValueStructure(value))
{
var valueStructure = valueMarshalStruct.ValueStructure;
NativeMethods.Execute(lib => lib.mdb_del(_handle, db._handle, ref keyStructure, ref valueStructure));
return;
}
}
NativeMethods.Execute(lib => lib.mdb_del(_handle, db._handle, ref keyStructure, IntPtr.Zero));
}
}
/// <summary>
/// Put data into a database.
/// </summary>
/// <param name="db">Database.</param>
/// <param name="key">Key byte array.</param>
/// <param name="value">Value byte array.</param>
/// <param name="options">Operation options (optional).</param>
public void Put(LightningDatabase db, byte[] key, byte[] value, PutOptions options = PutOptions.None)
{
if (db == null)
throw new ArgumentNullException("db");
using (var keyStructureMarshal = new MarshalValueStructure(key))
using (var valueStructureMarshal = new MarshalValueStructure(value))
{
var keyStruct = keyStructureMarshal.ValueStructure;
var valueStruct = valueStructureMarshal.ValueStructure;
NativeMethods.Execute(lib => lib.mdb_put(_handle, db._handle, ref keyStruct, ref valueStruct, options));
}
}
private bool TryGetInternal(UInt32 dbi, byte[] key, out Func<byte[]> valueFactory)
{
valueFactory = null;
using (var keyMarshalStruct = new MarshalValueStructure(key))
{
var valueStruct = default(ValueStructure);
var keyStructure = keyMarshalStruct.ValueStructure;
var res = NativeMethods.Read(lib => lib.mdb_get(_handle, dbi, ref keyStructure, out valueStruct));
var exists = res != NativeMethods.MDB_NOTFOUND;
if (exists)
valueFactory = () => valueStruct.ToByteArray(res);
return exists;
}
}
