1 /*
2 * Copyright 2014 The Netty Project
3 *
4 * The Netty Project licenses this file to you under the Apache License,
5 * version 2.0 (the "License"); you may not use this file except in compliance
6 * with the License. You may obtain a copy of the License at:
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
12 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
13 * License for the specific language governing permissions and limitations
14 * under the License.
15 */
16 package org.jboss.netty.handler.codec.spdy;
17
18 import static org.jboss.netty.handler.codec.spdy.SpdyCodecUtil.*;
19
20 import org.jboss.netty.buffer.ChannelBuffer;
21 import org.jboss.netty.buffer.ChannelBuffers;
22
23 import java.nio.ByteOrder;
24 import java.util.Set;
25
26 /**
27 * Encodes a SPDY Frame into a {@link ChannelBuffer}.
28 */
29 public class SpdyFrameEncoder {
30
31 private final int version;
32
33 /**
34 * Creates a new instance with the specified {@code spdyVersion}.
35 */
36 public SpdyFrameEncoder(SpdyVersion spdyVersion) {
37 if (spdyVersion == null) {
38 throw new NullPointerException("spdyVersion");
39 }
40 version = spdyVersion.getVersion();
41 }
42
43 private void writeControlFrameHeader(ChannelBuffer buffer, int type, byte flags, int length) {
44 buffer.writeShort(version | 0x8000);
45 buffer.writeShort(type);
46 buffer.writeByte(flags);
47 buffer.writeMedium(length);
48 }
49
50 public ChannelBuffer encodeDataFrame(int streamId, boolean last, ChannelBuffer data) {
51 byte flags = last ? SPDY_DATA_FLAG_FIN : 0;
52 ChannelBuffer header = ChannelBuffers.buffer(ByteOrder.BIG_ENDIAN, SPDY_HEADER_SIZE);
53 header.writeInt(streamId & 0x7FFFFFFF);
54 header.writeByte(flags);
55 header.writeMedium(data.readableBytes());
56 return ChannelBuffers.wrappedBuffer(header, data);
57 }
58
59 public ChannelBuffer encodeSynStreamFrame(
60 int streamId, int associatedToStreamId, byte priority, boolean last, boolean unidirectional,
61 ChannelBuffer headerBlock) {
62 byte flags = last ? SPDY_FLAG_FIN : 0;
63 if (unidirectional) {
64 flags |= SPDY_FLAG_UNIDIRECTIONAL;
65 }
66 int length = 10 + headerBlock.readableBytes();
67 ChannelBuffer frame = ChannelBuffers.buffer(ByteOrder.BIG_ENDIAN, SPDY_HEADER_SIZE + 10);
68 writeControlFrameHeader(frame, SPDY_SYN_STREAM_FRAME, flags, length);
69 frame.writeInt(streamId);
70 frame.writeInt(associatedToStreamId);
71 frame.writeShort((priority & 0xFF) << 13);
72 return ChannelBuffers.wrappedBuffer(frame, headerBlock);
73 }
74
75 public ChannelBuffer encodeSynReplyFrame(int streamId, boolean last, ChannelBuffer headerBlock) {
76 byte flags = last ? SPDY_FLAG_FIN : 0;
77 int length = 4 + headerBlock.readableBytes();
78 ChannelBuffer frame = ChannelBuffers.buffer(ByteOrder.BIG_ENDIAN, SPDY_HEADER_SIZE + 4);
79 writeControlFrameHeader(frame, SPDY_SYN_REPLY_FRAME, flags, length);
80 frame.writeInt(streamId);
81 return ChannelBuffers.wrappedBuffer(frame, headerBlock);
82 }
83
84 public ChannelBuffer encodeRstStreamFrame(int streamId, int statusCode) {
85 byte flags = 0;
86 int length = 8;
87 ChannelBuffer frame = ChannelBuffers.buffer(ByteOrder.BIG_ENDIAN, SPDY_HEADER_SIZE + length);
88 writeControlFrameHeader(frame, SPDY_RST_STREAM_FRAME, flags, length);
89 frame.writeInt(streamId);
90 frame.writeInt(statusCode);
91 return frame;
92 }
93
94 public ChannelBuffer encodeSettingsFrame(SpdySettingsFrame spdySettingsFrame) {
95 Set<Integer> ids = spdySettingsFrame.getIds();
96 int numSettings = ids.size();
97
98 byte flags = spdySettingsFrame.clearPreviouslyPersistedSettings() ?
99 SPDY_SETTINGS_CLEAR : 0;
100 int length = 4 + 8 * numSettings;
101 ChannelBuffer frame = ChannelBuffers.buffer(ByteOrder.BIG_ENDIAN, SPDY_HEADER_SIZE + length);
102 writeControlFrameHeader(frame, SPDY_SETTINGS_FRAME, flags, length);
103 frame.writeInt(numSettings);
104 for (Integer id : ids) {
105 flags = 0;
106 if (spdySettingsFrame.isPersistValue(id)) {
107 flags |= SPDY_SETTINGS_PERSIST_VALUE;
108 }
109 if (spdySettingsFrame.isPersisted(id)) {
110 flags |= SPDY_SETTINGS_PERSISTED;
111 }
112 frame.writeByte(flags);
113 frame.writeMedium(id);
114 frame.writeInt(spdySettingsFrame.getValue(id));
115 }
116 return frame;
117 }
118
119 public ChannelBuffer encodePingFrame(int id) {
120 byte flags = 0;
121 int length = 4;
122 ChannelBuffer frame = ChannelBuffers.buffer(ByteOrder.BIG_ENDIAN, SPDY_HEADER_SIZE + length);
123 writeControlFrameHeader(frame, SPDY_PING_FRAME, flags, length);
124 frame.writeInt(id);
125 return frame;
126 }
127
128 public ChannelBuffer encodeGoAwayFrame(int lastGoodStreamId, int statusCode) {
129 byte flags = 0;
130 int length = 8;
131 ChannelBuffer frame = ChannelBuffers.buffer(ByteOrder.BIG_ENDIAN, SPDY_HEADER_SIZE + length);
132 writeControlFrameHeader(frame, SPDY_GOAWAY_FRAME, flags, length);
133 frame.writeInt(lastGoodStreamId);
134 frame.writeInt(statusCode);
135 return frame;
136 }
137
138 public ChannelBuffer encodeHeadersFrame(int streamId, boolean last, ChannelBuffer headerBlock) {
139 byte flags = last ? SPDY_FLAG_FIN : 0;
140 int length = 4 + headerBlock.readableBytes();
141 ChannelBuffer frame = ChannelBuffers.buffer(ByteOrder.BIG_ENDIAN, SPDY_HEADER_SIZE + 4);
142 writeControlFrameHeader(frame, SPDY_HEADERS_FRAME, flags, length);
143 frame.writeInt(streamId);
144 return ChannelBuffers.wrappedBuffer(frame, headerBlock);
145 }
146
147 public ChannelBuffer encodeWindowUpdateFrame(int streamId, int deltaWindowSize) {
148 byte flags = 0;
149 int length = 8;
150 ChannelBuffer frame = ChannelBuffers.buffer(ByteOrder.BIG_ENDIAN, SPDY_HEADER_SIZE + length);
151 writeControlFrameHeader(frame, SPDY_WINDOW_UPDATE_FRAME, flags, length);
152 frame.writeInt(streamId);
153 frame.writeInt(deltaWindowSize);
154 return frame;
155 }
156 }
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