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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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/*
 * Copyright 2014 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:
 *
 *   https://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.spdy;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.ByteBufAllocator;
import io.netty.util.internal.ObjectUtil;

import static io.netty.handler.codec.spdy.SpdyCodecUtil.getSignedInt;

public class SpdyHeaderBlockRawDecoder extends SpdyHeaderBlockDecoder {

    private static final int LENGTH_FIELD_SIZE = 4;

    private final int maxHeaderSize;

    private State state;

    private ByteBuf cumulation;

    private int headerSize;
    private int numHeaders;
    private int length;
    private String name;

    private enum State {
        READ_NUM_HEADERS,
        READ_NAME_LENGTH,
        READ_NAME,
        SKIP_NAME,
        READ_VALUE_LENGTH,
        READ_VALUE,
        SKIP_VALUE,
        END_HEADER_BLOCK,
        ERROR
    }

    public SpdyHeaderBlockRawDecoder(SpdyVersion spdyVersion, int maxHeaderSize) {
        ObjectUtil.checkNotNull(spdyVersion, "spdyVersion");
        this.maxHeaderSize = maxHeaderSize;
        state = State.READ_NUM_HEADERS;
    }

    private static int readLengthField(ByteBuf buffer) {
        int length = getSignedInt(buffer, buffer.readerIndex());
        buffer.skipBytes(LENGTH_FIELD_SIZE);
        return length;
    }

    @Override
    void decode(ByteBufAllocator alloc, ByteBuf headerBlock, SpdyHeadersFrame frame) throws Exception {
        ObjectUtil.checkNotNull(headerBlock, "headerBlock");
        ObjectUtil.checkNotNull(frame, "frame");

        if (cumulation == null) {
            decodeHeaderBlock(headerBlock, frame);
            if (headerBlock.isReadable()) {
                cumulation = alloc.buffer(headerBlock.readableBytes());
                cumulation.writeBytes(headerBlock);
            }
        } else {
            cumulation.writeBytes(headerBlock);
            decodeHeaderBlock(cumulation, frame);
            if (cumulation.isReadable()) {
                cumulation.discardReadBytes();
            } else {
                releaseBuffer();
            }
        }
    }

    protected void decodeHeaderBlock(ByteBuf headerBlock, SpdyHeadersFrame frame) throws Exception {
        int skipLength;
        while (headerBlock.isReadable()) {
            switch(state) {
                case READ_NUM_HEADERS:
                    if (headerBlock.readableBytes() < LENGTH_FIELD_SIZE) {
                        return;
                    }

                    numHeaders = readLengthField(headerBlock);

                    if (numHeaders < 0) {
                        state = State.ERROR;
                        frame.setInvalid();
                    } else if (numHeaders == 0) {
                        state = State.END_HEADER_BLOCK;
                    } else {
                        state = State.READ_NAME_LENGTH;
                    }
                    break;

                case READ_NAME_LENGTH:
                    if (headerBlock.readableBytes() < LENGTH_FIELD_SIZE) {
                        return;
                    }

                    length = readLengthField(headerBlock);

                    // Recipients of a zero-length name must issue a stream error
                    if (length <= 0) {
                        state = State.ERROR;
                        frame.setInvalid();
                    } else if (length > maxHeaderSize || headerSize > maxHeaderSize - length) {
                        headerSize = maxHeaderSize + 1;
                        state = State.SKIP_NAME;
                        frame.setTruncated();
                    } else {
                        headerSize += length;
                        state = State.READ_NAME;
                    }
                    break;

                case READ_NAME:
                    if (headerBlock.readableBytes() < length) {
                        return;
                    }

                    byte[] nameBytes = new byte[length];
                    headerBlock.readBytes(nameBytes);
                    name = new String(nameBytes, "UTF-8");

                    // Check for identically named headers
                    if (frame.headers().contains(name)) {
                        state = State.ERROR;
                        frame.setInvalid();
                    } else {
                        state = State.READ_VALUE_LENGTH;
                    }
                    break;

                case SKIP_NAME:
                    skipLength = Math.min(headerBlock.readableBytes(), length);
                    headerBlock.skipBytes(skipLength);
                    length -= skipLength;

                    if (length == 0) {
                        state = State.READ_VALUE_LENGTH;
                    }
                    break;

                case READ_VALUE_LENGTH:
                    if (headerBlock.readableBytes() < LENGTH_FIELD_SIZE) {
                        return;
                    }

                    length = readLengthField(headerBlock);

                    // Recipients of illegal value fields must issue a stream error
                    if (length < 0) {
                        state = State.ERROR;
                        frame.setInvalid();
                    } else if (length == 0) {
                        if (!frame.isTruncated()) {
                            // SPDY/3 allows zero-length (empty) header values
                            frame.headers().add(name, "");
                        }

                        name = null;
                        if (--numHeaders == 0) {
                            state = State.END_HEADER_BLOCK;
                        } else {
                            state = State.READ_NAME_LENGTH;
                        }

                    } else if (length > maxHeaderSize || headerSize > maxHeaderSize - length) {
                        headerSize = maxHeaderSize + 1;
                        name = null;
                        state = State.SKIP_VALUE;
                        frame.setTruncated();
                    } else {
                        headerSize += length;
                        state = State.READ_VALUE;
                    }
                    break;

                case READ_VALUE:
                    if (headerBlock.readableBytes() < length) {
                        return;
                    }

                    byte[] valueBytes = new byte[length];
                    headerBlock.readBytes(valueBytes);

                    // Add Name/Value pair to headers
                    int index = 0;
                    int offset = 0;

                    // Value must not start with a NULL character
                    if (valueBytes[0] == (byte) 0) {
                        state = State.ERROR;
                        frame.setInvalid();
                        break;
                    }

                    while (index < length) {
                        while (index < valueBytes.length && valueBytes[index] != (byte) 0) {
                            index ++;
                        }
                        if (index < valueBytes.length) {
                            // Received NULL character
                            if (index + 1 == valueBytes.length || valueBytes[index + 1] == (byte) 0) {
                                // Value field ended with a NULL character or
                                // received multiple, in-sequence NULL characters.
                                // Recipients of illegal value fields must issue a stream error
                                state = State.ERROR;
                                frame.setInvalid();
                                break;
                            }
                        }
                        String value = new String(valueBytes, offset, index - offset, "UTF-8");

                        try {
                            frame.headers().add(name, value);
                        } catch (IllegalArgumentException e) {
                            // Name contains NULL or non-ascii characters
                            state = State.ERROR;
                            frame.setInvalid();
                            break;
                        }
                        index ++;
                        offset = index;
                    }

                    name = null;

                    // If we broke out of the add header loop, break here
                    if (state == State.ERROR) {
                        break;
                    }

                    if (--numHeaders == 0) {
                        state = State.END_HEADER_BLOCK;
                    } else {
                        state = State.READ_NAME_LENGTH;
                    }
                    break;

                case SKIP_VALUE:
                    skipLength = Math.min(headerBlock.readableBytes(), length);
                    headerBlock.skipBytes(skipLength);
                    length -= skipLength;

                    if (length == 0) {
                        if (--numHeaders == 0) {
                            state = State.END_HEADER_BLOCK;
                        } else {
                            state = State.READ_NAME_LENGTH;
                        }
                    }
                    break;

                case END_HEADER_BLOCK:
                    state = State.ERROR;
                    frame.setInvalid();
                    break;

                case ERROR:
                    headerBlock.skipBytes(headerBlock.readableBytes());
                    return;

                default:
                    throw new Error("Shouldn't reach here.");
            }
        }
    }

    @Override
    void endHeaderBlock(SpdyHeadersFrame frame) throws Exception {
        if (state != State.END_HEADER_BLOCK) {
            frame.setInvalid();
        }

        releaseBuffer();

        // Initialize header block decoding fields
        headerSize = 0;
        name = null;
        state = State.READ_NUM_HEADERS;
    }

    @Override
    void end() {
        releaseBuffer();
    }

    private void releaseBuffer() {
        if (cumulation != null) {
            cumulation.release();
            cumulation = null;
        }
    }
}




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