| using Lucene.Net.Diagnostics; |
| using System; |
| using System.Runtime.CompilerServices; |
| |
| namespace Lucene.Net.Util.Packed |
| { |
| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| using DataOutput = Lucene.Net.Store.DataOutput; |
| |
| /// <summary> |
| /// A <see cref="DataOutput"/> wrapper to write unaligned, variable-length packed |
| /// integers. |
| /// <para/> |
| /// @lucene.internal |
| /// </summary> |
| /// <seealso cref="PackedDataInput"/> |
| public sealed class PackedDataOutput |
| { |
| internal readonly DataOutput @out; |
| internal long current; |
| internal int remainingBits; |
| |
| /// <summary> |
| /// Create a new instance that wraps <paramref name="out"/>. |
| /// </summary> |
| public PackedDataOutput(DataOutput @out) |
| { |
| this.@out = @out; |
| current = 0; |
| remainingBits = 8; |
| } |
| |
| /// <summary> |
| /// Write a value using exactly <paramref name="bitsPerValue"/> bits. |
| /// <para/> |
| /// NOTE: This was writeLong() in Lucene. |
| /// </summary> |
| public void WriteInt64(long value, int bitsPerValue) |
| { |
| if (Debugging.AssertsEnabled) Debugging.Assert(bitsPerValue == 64 || (value >= 0 && value <= PackedInt32s.MaxValue(bitsPerValue))); |
| while (bitsPerValue > 0) |
| { |
| if (remainingBits == 0) |
| { |
| @out.WriteByte((byte)current); |
| current = 0L; |
| remainingBits = 8; |
| } |
| int bits = Math.Min(remainingBits, bitsPerValue); |
| current = current | ((((long)((ulong)value >> (bitsPerValue - bits))) & ((1L << bits) - 1)) << (remainingBits - bits)); |
| bitsPerValue -= bits; |
| remainingBits -= bits; |
| } |
| } |
| |
| /// <summary> |
| /// Flush pending bits to the underlying <see cref="DataOutput"/>. |
| /// </summary> |
| [MethodImpl(MethodImplOptions.NoInlining)] |
| public void Flush() |
| { |
| if (remainingBits < 8) |
| { |
| @out.WriteByte((byte)current); |
| } |
| remainingBits = 8; |
| current = 0L; |
| } |
| } |
| } |