8240903: Add test to check that jmod hashes are reproducible

Reviewed-by: mdoerr
Backport-of: 9695283458c273c2a4121f88a2a971ad4f297d5b

Author: RealCLanger

test/jdk/tools/jmod/hashes/HashesOrderTest.java

@@ -0,0 +1,162 @@
+/*
+ * Copyright (c) 2022, Huawei Technologies Co., Ltd. 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 8240903
+ * @summary Test consistency of moduleHashes attribute between builds
+ * @library /test/lib
+ * @run testng HashesOrderTest
+ */
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+import java.util.spi.ToolProvider;
+import java.util.stream.Collectors;
+
+import jdk.test.lib.compiler.ModuleInfoMaker;
+
+import org.testng.annotations.Test;
+
+import static org.testng.Assert.assertEquals;
+
+public class HashesOrderTest {
+    private ToolProvider JMOD_TOOL = ToolProvider.findFirst("jmod")
+        .orElseThrow(() ->
+            new RuntimeException("jmod tool not found")
+        );
+
+    // buffer size used for reading and writing
+    private static final int BUFFER_SIZE = 8192;
+
+    private int NUM_MODULES = 64;
+    private Path mods;
+    private Path lib1;
+    private Path lib2;
+    private ModuleInfoMaker builder;
+
+    @Test
+    public void test() throws Exception {
+        mods = Path.of("mods");
+        lib1 = Path.of("lib1");
+        lib2 = Path.of("lib2");
+        builder = new ModuleInfoMaker(Path.of("src"));
+
+        Files.createDirectories(mods);
+        Files.createDirectories(lib1);
+        Files.createDirectories(lib2);
+
+        makeModule("ma");
+        String moduleName;
+        for (int i = 0; i < NUM_MODULES; i++) {
+            moduleName = "m" + i + "b";
+            makeModule(moduleName, "ma");
+            makeJmod(moduleName, lib1);
+            makeJmod(moduleName, lib2);
+        }
+        makeJmod("ma", lib1, "--module-path", lib1.toString(),
+                "--hash-modules", ".*");
+        Path jmod1 = lib1.resolve("ma.jmod");
+
+        makeJmod("ma", lib2, "--module-path", lib2.toString(),
+                "--hash-modules", ".*");
+        Path jmod2 = lib2.resolve("ma.jmod");
+
+        assertEquals(mismatch(jmod1, jmod2), -1);
+    }
+
+    private void makeModule(String mn, String... deps)
+        throws IOException
+    {
+        StringBuilder sb = new StringBuilder();
+        sb.append("module ")
+          .append(mn)
+          .append(" {")
+          .append("\n");
+        Arrays.stream(deps)
+              .forEach(req -> {
+                  sb.append("    requires ");
+                  sb.append(req)
+                    .append(";\n");
+              });
+        sb.append("}\n");
+        builder.writeJavaFiles(mn, sb.toString());
+        builder.compile(mn, mods);
+    }
+
+    private void makeJmod(String moduleName, Path libName, String... options) {
+        Path mclasses = mods.resolve(moduleName);
+        Path outfile = libName.resolve(moduleName + ".jmod");
+        List<String> args = new ArrayList<>();
+        args.add("create");
+        Collections.addAll(args, options);
+        Collections.addAll(args, "--class-path", mclasses.toString(),
+                           outfile.toString());
+
+        runJmod(args);
+    }
+
+    private void runJmod(List<String> args) {
+        runJmod(args.toArray(new String[args.size()]));
+    }
+
+    private void runJmod(String... args) {
+        int rc = JMOD_TOOL.run(System.out, System.out, args);
+        System.out.println("jmod " + Arrays.stream(args).collect(Collectors.joining(" ")));
+        if (rc != 0) {
+            throw new AssertionError("jmod failed: rc = " + rc);
+        }
+    }
+
+    private long mismatch(Path path, Path path2) throws IOException {
+        if (Files.isSameFile(path, path2)) {
+            return -1;
+        }
+        byte[] buffer1 = new byte[BUFFER_SIZE];
+        byte[] buffer2 = new byte[BUFFER_SIZE];
+        try (InputStream in1 = Files.newInputStream(path);
+             InputStream in2 = Files.newInputStream(path2);) {
+            long totalRead = 0;
+            while (true) {
+                int nRead1 = in1.readNBytes(buffer1, 0, BUFFER_SIZE);
+                int nRead2 = in2.readNBytes(buffer2, 0, BUFFER_SIZE);
+
+                int i = Arrays.mismatch(buffer1, 0, nRead1, buffer2, 0, nRead2);
+                if (i > -1) {
+                    return totalRead + i;
+                }
+                if (nRead1 < BUFFER_SIZE) {
+                    // we've reached the end of the files, but found no mismatch
+                    return -1;
+                }
+                totalRead += nRead1;
+            }
+        }
+    }
+}