code: /*
   * Copyright (c) 2017-2018 The Regents of the University of California
   *
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions are
   * met:
   *
   * 1. Redistributions of source code must retain the above copyright
   * notice, this list of conditions and the following disclaimer.
   *
   * 2. Redistributions in binary form must reproduce the above copyright
   * notice, this list of conditions and the following disclaimer in the
   * documentation and/or other materials provided with the distribution.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
   * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  package edu.berkeley.cs.jqf.fuzz.junit.quickcheck;
  
  import java.io.EOFException;
  import java.io.IOException;
  import java.io.InputStream;
  
  import com.pholser.junit.quickcheck.generator.GenerationStatus;
  import com.pholser.junit.quickcheck.generator.Generator;
  import com.pholser.junit.quickcheck.random.SourceOfRandomness;
  
  /**
   * Lazy provider of bytes from an input stream. This is useful
   * when you want the parameter sequence to be exactly equal to
   * the raw input, such as when fuzzing with AFL.
   *
   * Use this only with AFL-like front-ends, which return
   * bytes from a fixed-size file. This generator may not work
   * properly with front-ends like Zest that generate fresh
   * values at the end of a parameter sequence, since that would
   * make the InputStream infinitely long.
   *
   * @author Rohan Padhye
   */
  public class InputStreamGenerator extends Generator<InputStream> {
      public InputStreamGenerator() {
          super(InputStream.class);
      }
  
      @Override
      public InputStream generate(SourceOfRandomness sourceOfRandomness, GenerationStatus generationStatus) {
          return new InputStream() {
             @Override
             public int read() throws IOException {
                 // Keep asking for new random bytes until the
                 // SourceOfRandomness runs out of parameters. This is designed
                 // to work with fixed-size parameter sequences, such as when
                 // fuzzing with AFL.
                 try {
                     byte nextByte = sourceOfRandomness.nextByte(Byte.MIN_VALUE, Byte.MAX_VALUE);
                     int nextInt = nextByte & 0xFF;
                     return nextInt;
                 } catch (IllegalStateException e) {
                     if (e.getCause() instanceof EOFException) {
                         return -1;
                     } else {
                         throw e;
                     }
                 }
             }
         };
      }
  }
  