undefect. CWE-407 — 63 sites patched across 27 ecosystems

Authors: russell@unturf.com · brackishbert@gmail.com · foxhop.net · TimeHexOn.com Patches, unit tests, benchmarks, whitepaper, and outreach briefs. Public domain — no copyright claimed. Use freely.
2026-03-26 17:11:57 -04:00 · 2026-03-26 17:11:57 -04:00 · 0a580b313d
commit 0a580b313d
70422 changed files with 17213626 additions and 0 deletions
--- a/test/jdk/java/util/concurrent/Exchanger/ExchangeLoops.java
+++ b/test/jdk/java/util/concurrent/Exchanger/ExchangeLoops.java
@ -0,0 +1,143 @@
+/*
+ * 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.
+ */
+
+/*
+ * This file is available under and governed by the GNU General Public
+ * License version 2 only, as published by the Free Software Foundation.
+ * However, the following notice accompanied the original version of this
+ * file:
+ *
+ * Written by Doug Lea with assistance from members of JCP JSR-166
+ * Expert Group and released to the public domain, as explained at
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/*
+ * @test
+ * @bug 4486658
+ * @summary checks to make sure a pipeline of exchangers passes data.
+ * @library /test/lib
+ */
+
+import static java.util.concurrent.TimeUnit.MILLISECONDS;
+
+import java.util.concurrent.CyclicBarrier;
+import java.util.concurrent.Exchanger;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import jdk.test.lib.Utils;
+
+public class ExchangeLoops {
+    static final long LONG_DELAY_MS = Utils.adjustTimeout(10_000);
+    static final ExecutorService pool = Executors.newCachedThreadPool();
+    static boolean print = false;
+
+    static class Int {
+        public int value;
+        Int(int i) { value = i; }
+    }
+
+    public static void main(String[] args) throws Exception {
+        int maxStages = 5;
+        int iters = 2000;
+
+        if (args.length > 0)
+            maxStages = Integer.parseInt(args[0]);
+
+        print = false;
+        System.out.println("Warmup...");
+        oneRun(2, iters);
+        print = true;
+
+        for (int i = 2; i <= maxStages; i += (i+1) >>> 1) {
+            System.out.print("Threads: " + i + "\t: ");
+            oneRun(i, iters);
+        }
+        pool.shutdown();
+        if (! pool.awaitTermination(LONG_DELAY_MS, MILLISECONDS))
+            throw new Error();
+   }
+
+    static class Stage implements Runnable {
+        final int iters;
+        final Exchanger<Int> left;
+        final Exchanger<Int> right;
+        final CyclicBarrier barrier;
+        volatile int result;
+        Stage(Exchanger<Int> left,
+              Exchanger<Int> right,
+              CyclicBarrier b, int iters) {
+            this.left = left;
+            this.right = right;
+            barrier = b;
+            this.iters = iters;
+        }
+
+        public void run() {
+            try {
+                barrier.await();
+                Int item = new Int(hashCode());
+                for (int i = 0; i < iters; ++i) {
+                    if (left != null) {
+                        item.value = LoopHelpers.compute1(item.value);
+                        Int other = left.exchange(item);
+                        if (other == item || other == null)
+                            throw new Error("Failed Exchange");
+                        item = other;
+
+                    }
+                    if (right != null) {
+                        item.value = LoopHelpers.compute2(item.value);
+                        Int other = right.exchange(item);
+                        if (other == item || other == null)
+                            throw new Error("Failed Exchange");
+                        item = other;
+                    }
+                }
+                barrier.await();
+
+            }
+            catch (Exception ex) {
+                ex.printStackTrace();
+                return;
+            }
+        }
+    }
+
+    static void oneRun(int nthreads, int iters) throws Exception {
+        LoopHelpers.BarrierTimer timer = new LoopHelpers.BarrierTimer();
+        CyclicBarrier barrier = new CyclicBarrier(nthreads + 1, timer);
+        Exchanger<Int> l = null;
+        Exchanger<Int> r = new Exchanger<>();
+        for (int i = 0; i < nthreads; ++i) {
+            pool.execute(new Stage(l, r, barrier, iters));
+            l = r;
+            r = (i+2 < nthreads) ? new Exchanger<Int>() : null;
+        }
+        barrier.await();
+        barrier.await();
+        long time = timer.getTime();
+        if (print)
+            System.out.println(LoopHelpers.rightJustify(time / (iters * nthreads + iters * (nthreads-2))) + " ns per transfer");
+    }
+
+}