/* * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ /* * @test * @bug 8155808 * @run main SkipTest * @summary verify skip method of Process Input Stream */ import java.io.BufferedOutputStream; import java.io.File; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; public class SkipTest { private static final String javaExe = System.getProperty("java.home") + File.separator + "bin" + File.separator + "java"; private static final String classpath = System.getProperty("java.class.path"); static final int BLOCK_SIZE = 10000; public static void main(String[] args) throws Throwable { // Start a Process to generate the test data to stdout and stderr ProcessBuilder pb = new ProcessBuilder(javaExe, "-classpath", classpath, "SkipTest$GenerateData"); System.out.printf("cmd: %s%n", pb.command()); Process process = pb.start(); /* * Verify the data expected is received mixing reads and skip. */ try (InputStream in = process.getInputStream()) { // Note: Process.getInputStream() actually returns a BufferedInputStream whose // skip() method works perfectly, partially obscuring the bug. Only when the // BufferedInputStream's buffer is drained, and it passes the skip() call to // the underlying native stream, does the problem occur. long n = in.skip(-1); if (n != 0) { throw new AssertionError("skip(-1) should return 0"); } n = in.skip(0); if (n != 0) { throw new AssertionError("skip(0) should return 0"); } // Now iterate all the data blocks int header; for (int expectedHeader = 'A'; (header = in.read()) != -1; expectedHeader++) { // The header byte should be simple 'A' to 'Z'. // When the bug hits, we will get lowercase letters instead. if (header != expectedHeader) { throw new AssertionError("header char wrong, expected: " + expectedHeader + ", actual: " + header); } // Handle the data bytes. // If the correct number of bytes are not skipped, // then subsequent reads become out-of-sync; int remaining = BLOCK_SIZE; do { remaining -= in.skip(remaining); } while (remaining != 0); } n = in.skip(1); if (n != 0) { throw new AssertionError("skip(1) at eof should return 0"); } } /** * Do the same for the standard error stream. */ try (InputStream in = process.getErrorStream()) { long n = in.skip(-1); if (n != 0) { throw new AssertionError("skip(-1) should return 0"); } n = in.skip(0); if (n != 0) { throw new AssertionError("skip(0) should return 0"); } // Now iterate all the data blocks int header; for (int expectedHeader = 'A'; (header = in.read()) != -1; expectedHeader++) { // The header byte should be simple 'A' to 'Z'. // When the bug hits, we will get lowercase letters instead. if (header != expectedHeader) { throw new AssertionError("header char wrong, expected: " + expectedHeader + ", actual: " + header); } // Handle the data bytes. // If the correct number of bytes are not skipped, // then subsequent reads become out-of-sync; int remaining = BLOCK_SIZE; do { remaining -= in.skip(remaining); } while (remaining != 0); } n = in.skip(1); if (n != 0) { throw new AssertionError("skip(1) at eof should return 0"); } } } /** * Alternate main to generate the test data to standard output * and standard error. */ static class GenerateData { public static void main(String[] args) { // Generate test data containing a series of data blocks of length BLOCK_SIZE, // each with a one-byte header. For example's sake, the "header" is a capital letter, // and the "data" is the lowercase version of that letter repeated BLOCK_SIZE times: try (OutputStream out = new BufferedOutputStream(System.out)) { for (int header = 'A'; header <= 'Z'; header++) { out.write(header); int data = Character.toLowerCase(header); for (int i = 0; i < BLOCK_SIZE; i++) { out.write(data); } } } catch (IOException ioe) { ioe.printStackTrace(); System.exit(1); } // Generate the same data to the error output try (OutputStream err = new BufferedOutputStream(System.err)) { for (int header = 'A'; header <= 'Z'; header++) { err.write(header); int data = Character.toLowerCase(header); for (int i = 0; i < BLOCK_SIZE; i++) { err.write(data); } } } catch (IOException ioe) { ioe.printStackTrace(); System.exit(1); } } } }