ByteInStream_Feed.java

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/**
 * Author: Sven Gothel <sgothel@jausoft.com>
 * Copyright (c) 2022-2023 Gothel Software e.K.
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
package org.jau.io;
 
import java.nio.ByteBuffer;
 
/**
 * Ringbuffer-Based byte input stream with an externally provisioned data feed.
 *
 * Instance uses the native C++ object `jau::io::ByteInStream_Feed`.
 */
public final class ByteInStream_Feed implements ByteInStream  {
    private volatile long nativeInstance;
    /* pp */ long getNativeInstance() { return nativeInstance; }
 
    /**
     * Construct a ringbuffer backed externally provisioned byte input stream
     * @param id_name arbitrary identifier for this instance
     * @param timeoutMS maximum duration in milliseconds to wait @ check_available() and write(), zero waits infinitely
     */
    public ByteInStream_Feed(final String id_name, final long timeoutMS) {
        try {
            nativeInstance = ctorImpl(id_name, timeoutMS);
        } catch (final Throwable t) {
            System.err.println("ByteInStream_Feed.ctor: native ctor failed: "+t.getMessage());
            throw t;
        }
    }
    private native long ctorImpl(final String id_name, final long timeoutMS);
 
    @Override
    public native void closeStream();
 
    @Override
    public void close() {
        final long handle;
        synchronized( this ) {
            handle = nativeInstance;
            nativeInstance = 0;
        }
        if( 0 != handle ) {
            dtorImpl(handle);
        }
    }
    private static native void dtorImpl(final long nativeInstance);
 
    @Override
    public void finalize() {
        close();
    }
 
    @Override
    public native boolean is_open();
 
    @Override
    public void clear(final IOState state) {
        clearImpl( state.mask );
    }
    private native void clearImpl(int s);
 
    @Override
    public IOState rdState() {
        return new IOState( rdStateImpl() );
    }
    private native int rdStateImpl();
 
    @Override
    public void setState(final IOState state) {
        setStateImpl( state.mask );
    }
    private native void setStateImpl(int s);
 
    @Override
    public native boolean good();
 
    @Override
    public native boolean eof();
 
    @Override
    public native boolean fail();
 
    @Override
    public native boolean bad();
 
    @Override
    public native boolean timeout();
 
    @Override
    public native boolean available(final long n);
 
    @Override
    public native int read(final byte[] out, final int offset, final int length);
 
    @Override
    public int read(final ByteBuffer out) {
        if( !Buffers.isDirect(out) ) {
            throw new IllegalArgumentException("out buffer not direct");
        }
        final int res = read2Impl(out, (int)Buffers.getDirectBufferByteOffset(out));
        out.limit(out.position() + res);
        return res;
    }
    private native int read2Impl(Object out, int out_offset);
 
    @Override
    public native int peek(byte[] out, final int offset, final int length, final long peek_offset);
 
    @Override
    public native String id();
 
    @Override
    public native long discard_next(long N);
 
    @Override
    public native long tellg();
 
    @Override
    public native boolean has_content_size();
 
    @Override
    public native long content_size();
 
    /**
     * Interrupt a potentially blocked reader.
     *
     * Call this method if intended to abort streaming and to interrupt the reader thread's potentially blocked check_available() call,
     * i.e. done at set_eof()
     *
     * @see set_eof()
     */
    public native void interruptReader();
 
    /**
     * Write given bytes to the async ringbuffer using explicit given timeout.
     *
     * Wait up to explicit given timeout duration until ringbuffer space is available, where fractions_i64::zero waits infinitely.
     *
     * This method is blocking.
     *
     * @param n byte count to wait for
     * @param in the byte array to transfer to the async ringbuffer
     * @param length the length of the byte array in
     * @param timeout explicit given timeout for async ringbuffer put operation
     * @return true if successful, otherwise false on timeout or stopped feeder and subsequent calls to good() will return false.
     */
    public boolean write(final byte[] in, final int offset, final int length, final long timeoutMS) {
        return write0Impl(in, offset, length, timeoutMS);
    }
    private native boolean write0Impl(final byte[] in, final int offset, final int length, final long timeoutMS);
 
    /**
     * Write given bytes to the async ringbuffer.
     *
     * Wait up to timeout duration set in constructor until ringbuffer space is available, where fractions_i64::zero waits infinitely.
     *
     * This method is blocking.
     *
     * @param in the byte array to transfer to the async ringbuffer
     * @param offset offset to in byte array to write
     * @param length number of in bytes to write starting at offset
     * @return true if successful, otherwise false on timeout or stopped feeder and subsequent calls to good() will return false.
     */
    public boolean write(final byte[] in, final int offset, final int length) {
        return write1Impl(in, offset, length);
    }
    private native boolean write1Impl(final byte[] in, final int offset, final int length);
 
    /**
     * Write given bytes to the async ringbuffer.
     *
     * Wait up to timeout duration set in constructor until ringbuffer space is available, where fractions_i64::zero waits infinitely.
     *
     * This method is blocking.
     *
     * @param in the direct {@link ByteBuffer} to transfer to the async ringbuffer starting at its {@link ByteBuffer#position() position} up to its {@link ByteBuffer#limit() limit}.
     *            {@link ByteBuffer#limit() Limit} will be reset to {@link ByteBuffer#position() position}.
     * @return true if successful, otherwise false on timeout or stopped feeder and subsequent calls to good() will return false.
     */
    public boolean write(final ByteBuffer in) {
        if( !Buffers.isDirect(in) ) {
            throw new IllegalArgumentException("out buffer not direct");
        }
        if( write2Impl(in, (int)Buffers.getDirectBufferByteOffset(in), in.limit()) ) {
            in.limit(in.position());
            return true;
        } else {
            return false;
        }
    }
    private native boolean write2Impl(ByteBuffer out, int out_offset, int out_limit);
 
    /**
     * Set known content size, informal only.
     * @param content_length the content size in bytes
     */
    public native void set_content_size(final long size);
 
    /**
     * Set end-of-data (EOS), i.e. when feeder completed provisioning bytes.
     *
     * Implementation issues interruptReader() to unblock a potentially blocked reader thread.
     *
     * @param result should be either -1 for FAILED or 1 for SUCCESS.
     *
     * @see interruptReader()
     */
    public native void set_eof(final int result);
 
    @Override
    public native String toString();
}