Fix the random number generation

mrigger · mrigger · commit 669569ebc236 · 2020-08-14T11:52:47.000+02:00
Previously, the random number data generation consistently generated the same data sequence for every thread's database. This seems to have been introduced in commit 183b93e.
diff --git a/src/sqlancer/Main.java b/src/sqlancer/Main.java
@@ -296,17 +296,17 @@ public static class DBMSExecutor<G extends GlobalState<O, ?>, O extends DBMSSpec
         private final MainOptions options;
         private final O command;
         private final String databaseName;
-        private final long seed;
         private StateLogger logger;
         private StateToReproduce stateToRepro;
+        private final Randomly r;
 
         public DBMSExecutor(DatabaseProvider<G, O> provider, MainOptions options, O dbmsSpecificOptions,
-                String databaseName, long seed) {
+                String databaseName, Randomly r) {
             this.provider = provider;
             this.options = options;
             this.databaseName = databaseName;
-            this.seed = seed;
             this.command = dbmsSpecificOptions;
+            this.r = r;
         }
 
         private G createGlobalState() {
@@ -324,10 +324,9 @@ public O getCommand() {
         public void run() throws SQLException {
             G state = createGlobalState();
             stateToRepro = provider.getStateToReproduce(databaseName);
-            stateToRepro.seedValue = seed;
+            stateToRepro.seedValue = r.getSeed();
             state.setState(stateToRepro);
             logger = new StateLogger(databaseName, provider, options);
-            Randomly r = new Randomly(seed);
             state.setRandomly(r);
             state.setDatabaseName(databaseName);
             state.setMainOptions(options);
@@ -390,10 +389,10 @@ public O getCommand() {
         }
 
         @SuppressWarnings("unchecked")
-        public DBMSExecutor<G, O> getDBMSExecutor(String databaseName, long seed) {
+        public DBMSExecutor<G, O> getDBMSExecutor(String databaseName, Randomly r) {
             try {
                 return new DBMSExecutor<G, O>(provider.getClass().getDeclaredConstructor().newInstance(), options,
-                        command, databaseName, seed);
+                        command, databaseName, r);
             } catch (Exception e) {
                 throw new AssertionError(e);
             }
@@ -461,7 +460,6 @@ private String formatInteger(long intValue) {
             } else {
                 seed = options.getRandomSeed() + i;
             }
-
             execService.execute(new Runnable() {
 
                 @Override
@@ -471,17 +469,17 @@ public void run() {
                 }
 
                 private void runThread(final String databaseName) {
+                    Randomly r = new Randomly(seed);
                     try {
                         if (options.getMaxGeneratedDatabases() == -1) {
                             // run without a limit
                             boolean continueRunning = true;
                             while (continueRunning) {
-                                continueRunning = run(options, execService, executorFactory, seed, databaseName);
+                                continueRunning = run(options, execService, executorFactory, r, databaseName);
                             }
                         } else {
                             for (int i = 0; i < options.getMaxGeneratedDatabases(); i++) {
-                                boolean continueRunning = run(options, execService, executorFactory, seed,
-                                        databaseName);
+                                boolean continueRunning = run(options, execService, executorFactory, r, databaseName);
                                 if (!continueRunning) {
                                     break;
                                 }
@@ -496,8 +494,8 @@ private void runThread(final String databaseName) {
                 }
 
                 private boolean run(MainOptions options, ExecutorService execService,
-                        DBMSExecutorFactory<?, ?> executorFactory, final long seed, final String databaseName) {
-                    DBMSExecutor<?, ?> executor = executorFactory.getDBMSExecutor(databaseName, seed);
+                        DBMSExecutorFactory<?, ?> executorFactory, Randomly r, final String databaseName) {
+                    DBMSExecutor<?, ?> executor = executorFactory.getDBMSExecutor(databaseName, r);
                     try {
                         executor.run();
                         return true;
diff --git a/src/sqlancer/Randomly.java b/src/sqlancer/Randomly.java
@@ -20,6 +20,7 @@ public final class Randomly {
     private Supplier<String> provider;
 
     private static final ThreadLocal<Random> THREAD_RANDOM = new ThreadLocal<>();
+    private long seed;
 
     private void addToCache(long val) {
         if (USE_CACHING && cachedLongs.size() < CACHE_SIZE && !cachedLongs.contains(val)) {
@@ -383,11 +384,12 @@ public Randomly(Supplier<String> provider) {
     }
 
     public Randomly() {
-        getThreadRandom().set(new Random());
+        THREAD_RANDOM.set(new Random());
     }
 
     public Randomly(long seed) {
-        getThreadRandom().set(new Random(seed));
+        this.seed = seed;
+        THREAD_RANDOM.set(new Random(seed));
     }
 
     public static double getUncachedDouble() {
@@ -429,4 +431,8 @@ private static int getNextInt(int lower, int upper) {
         return (int) getNextLong(lower, upper);
     }
 
+    public long getSeed() {
+        return seed;
+    }
+
 }

Original file line number	Diff line number	Diff line change
`@@ -20,6 +20,7 @@ public final class Randomly {`
`20`	`20`	`private Supplier<String> provider;`
`21`	`21`
`22`	`22`	`private static final ThreadLocal<Random> THREAD_RANDOM = new ThreadLocal<>();`
	`23`	`+ private long seed;`
`23`	`24`
`24`	`25`	`private void addToCache(long val) {`
`25`	`26`	`if (USE_CACHING && cachedLongs.size() < CACHE_SIZE && !cachedLongs.contains(val)) {`
`@@ -383,11 +384,12 @@ public Randomly(Supplier<String> provider) {`
`383`	`384`	`}`
`384`	`385`
`385`	`386`	`public Randomly() {`
`386`		`- getThreadRandom().set(new Random());`
	`387`	`+ THREAD_RANDOM.set(new Random());`
`387`	`388`	`}`
`388`	`389`
`389`	`390`	`public Randomly(long seed) {`
`390`		`- getThreadRandom().set(new Random(seed));`
	`391`	`+ this.seed = seed;`
	`392`	`+ THREAD_RANDOM.set(new Random(seed));`
`391`	`393`	`}`
`392`	`394`
`393`	`395`	`public static double getUncachedDouble() {`
`@@ -429,4 +431,8 @@ private static int getNextInt(int lower, int upper) {`
`429`	`431`	`return (int) getNextLong(lower, upper);`
`430`	`432`	`}`
`431`	`433`
	`434`	`+ public long getSeed() {`
	`435`	`+ return seed;`
	`436`	`+ }`
	`437`	`+`
`432`	`438`	`}`