1 | /** |
2 | * Licensed to the Apache Software Foundation (ASF) under one |
3 | * or more contributor license agreements. See the NOTICE file |
4 | * distributed with this work for additional information |
5 | * regarding copyright ownership. The ASF licenses this file |
6 | * to you under the Apache License, Version 2.0 (the |
7 | * "License"); you may not use this file except in compliance |
8 | * with the License. You may obtain a copy of the License at |
9 | * |
10 | * http://www.apache.org/licenses/LICENSE-2.0 |
11 | * |
12 | * Unless required by applicable law or agreed to in writing, software |
13 | * distributed under the License is distributed on an "AS IS" BASIS, |
14 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
15 | * See the License for the specific language governing permissions and |
16 | * limitations under the License. |
17 | */ |
18 | |
19 | #ifndef ORC_OUTPUTSTREAM_HH |
20 | #define ORC_OUTPUTSTREAM_HH |
21 | |
22 | #include "Adaptor.hh" |
23 | #include "orc/OrcFile.hh" |
24 | #include "wrap/zero-copy-stream-wrapper.h" |
25 | |
26 | namespace orc { |
27 | |
28 | /** |
29 | * Record write position for creating index stream |
30 | */ |
31 | class PositionRecorder { |
32 | public: |
33 | virtual ~PositionRecorder(); |
34 | virtual void add(uint64_t pos) = 0; |
35 | }; |
36 | |
37 | /** |
38 | * A subclass of Google's ZeroCopyOutputStream that supports output to memory |
39 | * buffer, and flushing to OutputStream. |
40 | * By extending Google's class, we get the ability to pass it directly |
41 | * to the protobuf writers. |
42 | */ |
43 | class BufferedOutputStream: public google::protobuf::io::ZeroCopyOutputStream { |
44 | private: |
45 | OutputStream * outputStream; |
46 | std::unique_ptr<DataBuffer<char> > dataBuffer; |
47 | uint64_t blockSize; |
48 | |
49 | public: |
50 | BufferedOutputStream(MemoryPool& pool, |
51 | OutputStream * outStream, |
52 | uint64_t capacity, |
53 | uint64_t block_size); |
54 | virtual ~BufferedOutputStream() override; |
55 | |
56 | virtual bool Next(void** data, int*size) override; |
57 | virtual void BackUp(int count) override; |
58 | virtual google::protobuf::int64 ByteCount() const override; |
59 | virtual bool WriteAliasedRaw(const void * data, int size) override; |
60 | virtual bool AllowsAliasing() const override; |
61 | |
62 | virtual std::string getName() const; |
63 | virtual uint64_t getSize() const; |
64 | virtual uint64_t flush(); |
65 | |
66 | virtual bool isCompressed() const { return false; } |
67 | }; |
68 | |
69 | /** |
70 | * An append only buffered stream that allows |
71 | * buffer, and flushing to OutputStream. |
72 | * By extending Google's class, we get the ability to pass it directly |
73 | * to the protobuf writers. |
74 | */ |
75 | class AppendOnlyBufferedStream { |
76 | private: |
77 | std::unique_ptr<BufferedOutputStream> outStream; |
78 | char * buffer; |
79 | int bufferOffset, bufferLength; |
80 | |
81 | public: |
82 | AppendOnlyBufferedStream(std::unique_ptr<BufferedOutputStream> _outStream) : |
83 | outStream(std::move(_outStream)) { |
84 | buffer = nullptr; |
85 | bufferOffset = bufferLength = 0; |
86 | } |
87 | |
88 | void write(const char * data, size_t size); |
89 | uint64_t getSize() const; |
90 | uint64_t flush(); |
91 | |
92 | void recordPosition(PositionRecorder* recorder) const; |
93 | }; |
94 | } |
95 | |
96 | #endif // ORC_OUTPUTSTREAM_HH |
97 | |