1/********************************************************************
2 * Copyright (c) 2013 - 2014, Pivotal Inc.
3 * All rights reserved.
4 *
5 * Author: Zhanwei Wang
6 ********************************************************************/
7/********************************************************************
8 * 2014 -
9 * open source under Apache License Version 2.0
10 ********************************************************************/
11/**
12 * Licensed to the Apache Software Foundation (ASF) under one
13 * or more contributor license agreements. See the NOTICE file
14 * distributed with this work for additional information
15 * regarding copyright ownership. The ASF licenses this file
16 * to you under the Apache License, Version 2.0 (the
17 * "License"); you may not use this file except in compliance
18 * with the License. You may obtain a copy of the License at
19 *
20 * http://www.apache.org/licenses/LICENSE-2.0
21 *
22 * Unless required by applicable law or agreed to in writing, software
23 * distributed under the License is distributed on an "AS IS" BASIS,
24 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
25 * See the License for the specific language governing permissions and
26 * limitations under the License.
27 */
28#ifndef _HDFS_LIBHDFS3_CLIENT_PACKET_H_
29#define _HDFS_LIBHDFS3_CLIENT_PACKET_H_
30
31#include <stdint.h>
32#include <vector>
33
34#define HEART_BEAT_SEQNO -1
35
36namespace Hdfs {
37namespace Internal {
38
39class ConstPacketBuffer {
40public:
41 ConstPacketBuffer(const char * buf, int size) :
42 buffer(buf), size(size) {
43 }
44
45 const char * getBuffer() const {
46 return buffer;
47 }
48
49 const int getSize() const {
50 return size;
51 }
52
53private:
54 const char * buffer;
55 const int size;
56};
57
58/**
59 * buffer is pointed into like follows:
60 * (C is checksum data, D is payload data)
61 *
62 * [HHHHHCCCCC________________DDDDDDDDDDDDDDDD___]
63 * ^ ^ ^ ^
64 * | checksumPos dataStart dataPos
65 * checksumStart
66 */
67class Packet {
68public:
69 /**
70 * create a heart beat packet
71 */
72 Packet();
73
74 /**
75 * create a new packet
76 */
77 Packet(int pktSize, int chunksPerPkt, int64_t offsetInBlock, int64_t seqno, int checksumSize);
78
79 void reset(int pktSize, int chunksPerPkt, int64_t offsetInBlock, int64_t seqno, int checksumSize);
80
81 void addChecksum(uint32_t checksum);
82
83 void addData(const char * buf, int size);
84
85 void setSyncFlag(bool sync);
86
87 void increaseNumChunks();
88
89 bool isFull();
90
91 bool isHeartbeat();
92
93 void setLastPacketInBlock(bool lastPacket);
94
95 int getDataSize();
96
97 const ConstPacketBuffer getBuffer();
98
99 int64_t getLastByteOffsetBlock();
100
101 int64_t getSeqno() const {
102 return seqno;
103 }
104
105 bool isLastPacketInBlock() const {
106 return lastPacketInBlock;
107 }
108
109 int64_t getOffsetInBlock() const {
110 return offsetInBlock;
111 }
112
113private:
114 bool lastPacketInBlock; // is this the last packet in block
115 bool syncBlock; // sync block to disk?
116 int checksumPos;
117 int checksumSize;
118 int checksumStart;
119 int dataPos;
120 int dataStart;
121 int headerStart;
122 int maxChunks; // max chunks in packet
123 int numChunks; // number of chunks currently in packet
124 int64_t offsetInBlock; // offset in block
125 int64_t seqno; // sequence number of packet in block
126 std::vector<char> buffer;
127};
128
129}
130}
131#endif /* _HDFS_LIBHDFS3_CLIENT_PACKET_H_ */
132