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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 2016 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.channel.kqueue;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.ByteBufAllocator;
import io.netty.channel.ChannelConfig;
import io.netty.channel.RecvByteBufAllocator.DelegatingHandle;
import io.netty.channel.RecvByteBufAllocator.ExtendedHandle;
import io.netty.channel.unix.PreferredDirectByteBufAllocator;
import io.netty.util.UncheckedBooleanSupplier;

import static java.lang.Math.max;
import static java.lang.Math.min;

final class KQueueRecvByteAllocatorHandle extends DelegatingHandle implements ExtendedHandle {
    private final PreferredDirectByteBufAllocator preferredDirectByteBufAllocator =
            new PreferredDirectByteBufAllocator();

    private final UncheckedBooleanSupplier defaultMaybeMoreDataSupplier = new UncheckedBooleanSupplier() {
        @Override
        public boolean get() {
            return maybeMoreDataToRead();
        }
    };
    private boolean overrideGuess;
    private boolean readEOF;
    private long numberBytesPending;

    KQueueRecvByteAllocatorHandle(ExtendedHandle handle) {
        super(handle);
    }

    @Override
    public int guess() {
        return overrideGuess ? guess0() : delegate().guess();
    }

    @Override
    public void reset(ChannelConfig config) {
        overrideGuess = ((KQueueChannelConfig) config).getRcvAllocTransportProvidesGuess();
        delegate().reset(config);
    }

    @Override
    public ByteBuf allocate(ByteBufAllocator alloc) {
        // We need to ensure we always allocate a direct ByteBuf as we can only use a direct buffer to read via JNI.
        preferredDirectByteBufAllocator.updateAllocator(alloc);
        return overrideGuess ? preferredDirectByteBufAllocator.ioBuffer(guess0()) :
                delegate().allocate(preferredDirectByteBufAllocator);
    }

    @Override
    public void lastBytesRead(int bytes) {
        numberBytesPending = bytes < 0 ? 0 : max(0, numberBytesPending - bytes);
        delegate().lastBytesRead(bytes);
    }

    @Override
    public boolean continueReading(UncheckedBooleanSupplier maybeMoreDataSupplier) {
        return ((ExtendedHandle) delegate()).continueReading(maybeMoreDataSupplier);
    }

    @Override
    public boolean continueReading() {
        // We must override the supplier which determines if there maybe more data to read.
        return continueReading(defaultMaybeMoreDataSupplier);
    }

    void readEOF() {
        readEOF = true;
    }

    boolean isReadEOF() {
        return readEOF;
    }

    void numberBytesPending(long numberBytesPending) {
        this.numberBytesPending = numberBytesPending;
    }

    boolean maybeMoreDataToRead() {
        /**
         * kqueue with EV_CLEAR flag set requires that we read until we consume "data" bytes
         * (see kqueue man). However in order to
         * respect auto read we supporting reading to stop if auto read is off. If auto read is on we force reading to
         * continue to avoid a {@link StackOverflowError} between channelReadComplete and reading from the
         * channel. It is expected that the {@link #KQueueSocketChannel} implementations will track if all data was not
         * read, and will force a EVFILT_READ ready event.
         *
         * It is assumed EOF is handled externally by checking {@link #isReadEOF()}.
         */
        return numberBytesPending != 0;
    }

    private int guess0() {
        return (int) min(numberBytesPending, Integer.MAX_VALUE);
    }
}