/*
* Copyright 2015 The Netty Project
*
* The Netty Project 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.
*/
/*
* Copyright 2014 Twitter, Inc.
*
* Licensed 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.
*/
package io.netty.handler.codec.http2;
import io.netty.handler.codec.UnsupportedValueConverter;
import io.netty.util.AsciiString;
import java.util.Arrays;
import java.util.List;
import static io.netty.handler.codec.http2.HpackUtil.equalsConstantTime;
final class HpackStaticTable {
// Appendix A: Static Table
// http://tools.ietf.org/html/rfc7541#appendix-A
private static final List<HpackHeaderField> STATIC_TABLE = Arrays.asList(
/* 1 */ newEmptyHeaderField(":authority"),
/* 2 */ newHeaderField(":method", "GET"),
/* 3 */ newHeaderField(":method", "POST"),
/* 4 */ newHeaderField(":path", "/"),
/* 5 */ newHeaderField(":path", "/index.html"),
/* 6 */ newHeaderField(":scheme", "http"),
/* 7 */ newHeaderField(":scheme", "https"),
/* 8 */ newHeaderField(":status", "200"),
/* 9 */ newHeaderField(":status", "204"),
/* 10 */ newHeaderField(":status", "206"),
/* 11 */ newHeaderField(":status", "304"),
/* 12 */ newHeaderField(":status", "400"),
/* 13 */ newHeaderField(":status", "404"),
/* 14 */ newHeaderField(":status", "500"),
/* 15 */ newEmptyHeaderField("accept-charset"),
/* 16 */ newHeaderField("accept-encoding", "gzip, deflate"),
/* 17 */ newEmptyHeaderField("accept-language"),
/* 18 */ newEmptyHeaderField("accept-ranges"),
/* 19 */ newEmptyHeaderField("accept"),
/* 20 */ newEmptyHeaderField("access-control-allow-origin"),
/* 21 */ newEmptyHeaderField("age"),
/* 22 */ newEmptyHeaderField("allow"),
/* 23 */ newEmptyHeaderField("authorization"),
/* 24 */ newEmptyHeaderField("cache-control"),
/* 25 */ newEmptyHeaderField("content-disposition"),
/* 26 */ newEmptyHeaderField("content-encoding"),
/* 27 */ newEmptyHeaderField("content-language"),
/* 28 */ newEmptyHeaderField("content-length"),
/* 29 */ newEmptyHeaderField("content-location"),
/* 30 */ newEmptyHeaderField("content-range"),
/* 31 */ newEmptyHeaderField("content-type"),
/* 32 */ newEmptyHeaderField("cookie"),
/* 33 */ newEmptyHeaderField("date"),
/* 34 */ newEmptyHeaderField("etag"),
/* 35 */ newEmptyHeaderField("expect"),
/* 36 */ newEmptyHeaderField("expires"),
/* 37 */ newEmptyHeaderField("from"),
/* 38 */ newEmptyHeaderField("host"),
/* 39 */ newEmptyHeaderField("if-match"),
/* 40 */ newEmptyHeaderField("if-modified-since"),
/* 41 */ newEmptyHeaderField("if-none-match"),
/* 42 */ newEmptyHeaderField("if-range"),
/* 43 */ newEmptyHeaderField("if-unmodified-since"),
/* 44 */ newEmptyHeaderField("last-modified"),
/* 45 */ newEmptyHeaderField("link"),
/* 46 */ newEmptyHeaderField("location"),
/* 47 */ newEmptyHeaderField("max-forwards"),
/* 48 */ newEmptyHeaderField("proxy-authenticate"),
/* 49 */ newEmptyHeaderField("proxy-authorization"),
/* 50 */ newEmptyHeaderField("range"),
/* 51 */ newEmptyHeaderField("referer"),
/* 52 */ newEmptyHeaderField("refresh"),
/* 53 */ newEmptyHeaderField("retry-after"),
/* 54 */ newEmptyHeaderField("server"),
/* 55 */ newEmptyHeaderField("set-cookie"),
/* 56 */ newEmptyHeaderField("strict-transport-security"),
/* 57 */ newEmptyHeaderField("transfer-encoding"),
/* 58 */ newEmptyHeaderField("user-agent"),
/* 59 */ newEmptyHeaderField("vary"),
/* 60 */ newEmptyHeaderField("via"),
/* 61 */ newEmptyHeaderField("www-authenticate")
);
private static HpackHeaderField newEmptyHeaderField(CharSequence name) {
return newHeaderField(name, AsciiString.EMPTY_STRING);
}
private static HpackHeaderField newHeaderField(CharSequence name, CharSequence value) {
return new HpackHeaderField(AsciiString.of(name), AsciiString.of(value));
}
private static final CharSequenceMap<Integer> STATIC_INDEX_BY_NAME = createMap();
/**
* The number of header fields in the static table.
*/
static final int length = STATIC_TABLE.size();
/**
* Return the header field at the given index value.
*/
static HpackHeaderField getEntry(int index) {
return STATIC_TABLE.get(index - 1);
}
/**
* Returns the lowest index value for the given header field name in the static table. Returns
* -1 if the header field name is not in the static table.
*/
static int getIndex(CharSequence name) {
Integer index = STATIC_INDEX_BY_NAME.get(name);
if (index == null) {
return -1;
}
return index;
}
/**
* Returns the index value for the given header field in the static table. Returns -1 if the
* header field is not in the static table.
*/
static int getIndex(CharSequence name, CharSequence value) {
int index = getIndex(name);
if (index == -1) {
return -1;
}
// Note this assumes all entries for a given header field are sequential.
while (index <= length) {
HpackHeaderField entry = getEntry(index);
if (equalsConstantTime(name, entry.name) == 0) {
break;
}
if (equalsConstantTime(value, entry.value) != 0) {
return index;
}
index++;
}
return -1;
}
// create a map CharSequenceMap header name to index value to allow quick lookup
private static CharSequenceMap<Integer> createMap() {
int length = STATIC_TABLE.size();
@SuppressWarnings("unchecked")
CharSequenceMap<Integer> ret = new CharSequenceMap<Integer>(true,
UnsupportedValueConverter.<Integer>instance(), length);
// Iterate through the static table in reverse order to
// save the smallest index for a given name in the map.
for (int index = length; index > 0; index--) {
HpackHeaderField entry = getEntry(index);
CharSequence name = entry.name;
ret.set(name, index);
}
return ret;
}
// singleton
private HpackStaticTable() {
}
}