MVStore: the Recover tool can now deal with more types of corruption in the…

MVStore: the Recover tool can now deal with more types of corruption in the file. MVStore: the TransactionStore now first needs to be initialized before it can be used.

h2/src/docsrc/html/changelog.html

@@ -17,7 +17,9 @@ Change Log
 <h1>Change Log</h1>
 
 <h2>Next Version (unreleased)</h2>
-<ul><li>Views and derived tables with equality and range conditions on the same columns
+<ul><li>MVStore: the Recover tool can now deal with more types of corruption in the file.
+</li><li>MVStore: the TransactionStore now first needs to be initialized before it can be used.
+</li><li>Views and derived tables with equality and range conditions on the same columns
     did not work properly. example: select x from (select x from (select 1 as x)
     where x &gt; 0 and x &lt; 2) where x = 1
 </li><li>The database URL setting PAGE_SIZE setting is now also used for the MVStore.

h2/src/main/org/h2/mvstore/DataUtils.java

@@ -88,6 +88,12 @@ public class DataUtils {
      */
     public static final int ERROR_TRANSACTION_STILL_OPEN = 102;
 
+    /**
+     * The transaction store is in an illegal state (for example, not yet
+     * initialized).
+     */
+    public static final int ERROR_TRANSACTION_ILLEGAL_STATE = 103;
+
     /**
      * The type for leaf page.
      */

h2/src/main/org/h2/mvstore/db/MVTableEngine.java

@@ -163,6 +163,7 @@ public class MVTableEngine implements TableEngine {
             this.transactionStore = new TransactionStore(
                     store,
                     new ValueDataType(null, db, null));
+            transactionStore.init();
         }
 
         public MVStore getStore() {

h2/src/main/org/h2/mvstore/db/TransactionStore.java

@@ -57,6 +57,8 @@ public class TransactionStore {
     
     private final DataType dataType;
 
+    private boolean init;
+
     private int lastTransactionId;
 
     private int maxTransactionId = 0xffff;
@@ -94,19 +96,33 @@ public class TransactionStore {
                 new MVMap.Builder<Long, Object[]>().
                 valueType(undoLogValueType);
         undoLog = store.openMap("undoLog", builder);
-        // remove all temporary maps
         if (undoLog.getValueType() != undoLogValueType) {
             throw DataUtils.newIllegalStateException(
                     DataUtils.ERROR_TRANSACTION_CORRUPT,
                     "Undo map open with a different value type");
         }
+    }
+    
+    /**
+     * Initialize the store. This is needed before a transaction can be opened.
+     * If the transaction store is corrupt, this method can throw an exception,
+     * in which case the store can only be used for reading.
+     */
+    public synchronized void init() {
+        init = true;
+        // remove all temporary maps
         for (String mapName : store.getMapNames()) {
             if (mapName.startsWith("temp.")) {
                 MVMap<Object, Integer> temp = openTempMap(mapName);
                 store.removeMap(temp);
             }
         }
-        init();
+        synchronized (undoLog) {
+            if (undoLog.size() > 0) {
+                Long key = undoLog.firstKey();
+                lastTransactionId = getTransactionId(key);
+            }
+        }
     }
 
     /**
@@ -155,15 +171,6 @@ public class TransactionStore {
         return operationId & ((1L << 40) - 1);
     }
 
-    private synchronized void init() {
-        synchronized (undoLog) {
-            if (undoLog.size() > 0) {
-                Long key = undoLog.firstKey();
-                lastTransactionId = getTransactionId(key);
-            }
-        }
-    }
-
     /**
      * Get the list of unclosed transactions that have pending writes.
      *
@@ -213,6 +220,11 @@ public class TransactionStore {
      * @return the transaction
      */
     public synchronized Transaction begin() {
+        if (!init) {
+            throw DataUtils.newIllegalStateException(
+                    DataUtils.ERROR_TRANSACTION_ILLEGAL_STATE, 
+                    "Not initialized");
+        }
         int transactionId = ++lastTransactionId;
         if (lastTransactionId >= maxTransactionId) {
             lastTransactionId = 0;

h2/src/main/org/h2/tools/Recover.java

@@ -591,6 +591,11 @@ public class Recover extends Tool implements DataHandler {
         dumpMeta(writer, mv);
         writer.println("-- Tables");
         TransactionStore store = new TransactionStore(mv);
+        try {
+            store.init();
+        } catch (Throwable e) {
+            writeError(writer, e);
+        }
         try {
             for (String mapName : mv.getMapNames()) {
                 if (!mapName.startsWith("table.")) {

h2/src/test/org/h2/test/store/TestMVTableEngine.java

@@ -424,6 +424,7 @@ public class TestMVTableEngine extends TestBase {
 
         MVStore store = MVStore.open(file);
         TransactionStore t = new TransactionStore(store);
+        t.init();
         assertEquals(0, t.getOpenTransactions().size());
         store.close();
     }

h2/src/test/org/h2/test/store/TestTransactionStore.java

@@ -65,6 +65,7 @@ public class TestTransactionStore extends TestBase {
         TransactionStore ts;
         s = MVStore.open(null);
         ts = new TransactionStore(s);
+        ts.init();
 
         Transaction tx1 = ts.begin();
         TransactionMap<Integer, Integer> map1 = tx1.openMap("data");
@@ -98,6 +99,7 @@ public class TestTransactionStore extends TestBase {
         TransactionStore ts;
         s = MVStore.open(null);
         ts = new TransactionStore(s);
+        ts.init();
 
         Transaction tx1 = ts.begin();
         TransactionMap<Integer, Integer> map1 = tx1.openMap("data");
@@ -125,6 +127,7 @@ public class TestTransactionStore extends TestBase {
         TransactionStore ts;
         s = MVStore.open(null);
         ts = new TransactionStore(s);
+        ts.init();
 
         Transaction tx0 = ts.begin();
         TransactionMap<Integer, Integer> map0 = tx0.openMap("data");
@@ -149,6 +152,7 @@ public class TestTransactionStore extends TestBase {
         TransactionStore ts;
         s = MVStore.open(null);
         ts = new TransactionStore(s);
+        ts.init();
         ts.setMaxTransactionId(16);
         for (int i = 0, j = 1; i < 64; i++) {
             Transaction t = ts.begin();
@@ -161,6 +165,7 @@ public class TestTransactionStore extends TestBase {
         }
         s = MVStore.open(null);
         ts = new TransactionStore(s);
+        ts.init();
         ts.setMaxTransactionId(16);
         ArrayList<Transaction> fifo = New.arrayList();
         int open = 0;
@@ -197,6 +202,7 @@ public class TestTransactionStore extends TestBase {
 
             s = MVStore.open(fileName);
             ts = new TransactionStore(s);
+            ts.init();
             tx = ts.begin();
             s.setReuseSpace(false);
             m = tx.openMap("test");
@@ -260,6 +266,7 @@ public class TestTransactionStore extends TestBase {
     private void testGetModifiedMaps() {
         MVStore s = MVStore.open(null);
         TransactionStore ts = new TransactionStore(s);
+        ts.init();
         Transaction tx;
         TransactionMap<String, String> m1, m2, m3;
         long sp;
@@ -329,6 +336,7 @@ public class TestTransactionStore extends TestBase {
     private void testKeyIterator() {
         MVStore s = MVStore.open(null);
         TransactionStore ts = new TransactionStore(s);
+        ts.init();
         Transaction tx, tx2;
         TransactionMap<String, String> m, m2;
         Iterator<String> it, it2;
@@ -382,6 +390,8 @@ public class TestTransactionStore extends TestBase {
     private void testMultiStatement() {
         MVStore s = MVStore.open(null);
         TransactionStore ts = new TransactionStore(s);
+        ts.init();
+
         Transaction tx;
         TransactionMap<String, String> m;
         long startUpdate;
@@ -470,6 +480,7 @@ public class TestTransactionStore extends TestBase {
 
         s = MVStore.open(fileName);
         ts = new TransactionStore(s);
+        ts.init();
         tx = ts.begin();
         assertEquals(null, tx.getName());
         tx.setName("first transaction");
@@ -489,6 +500,7 @@ public class TestTransactionStore extends TestBase {
 
         s = MVStore.open(fileName);
         ts = new TransactionStore(s);
+        ts.init();
         tx = ts.begin();
         assertEquals(2, tx.getId());
         m = tx.openMap("test");
@@ -507,6 +519,7 @@ public class TestTransactionStore extends TestBase {
 
         s = MVStore.open(fileName);
         ts = new TransactionStore(s);
+        ts.init();
         tx = ts.begin();
         m = tx.openMap("test");
         assertEquals(2, tx.getId());
@@ -531,6 +544,7 @@ public class TestTransactionStore extends TestBase {
     private void testSavepoint() {
         MVStore s = MVStore.open(null);
         TransactionStore ts = new TransactionStore(s);
+        ts.init();
         Transaction tx;
         TransactionMap<String, String> m;
 
@@ -584,6 +598,7 @@ public class TestTransactionStore extends TestBase {
 
         MVStore s = MVStore.open(null);
         TransactionStore ts = new TransactionStore(s);
+        ts.init();
         for (int i = 0; i < connectionCount; i++) {
             Statement stat = statements.get(i);
             // 100 ms to avoid blocking (the test is single threaded)
@@ -717,6 +732,7 @@ public class TestTransactionStore extends TestBase {
         MVStore s = MVStore.open(null);
 
         TransactionStore ts = new TransactionStore(s);
+        ts.init();
 
         Transaction tx1, tx2;
         TransactionMap<String, String> m1, m2;
@@ -789,6 +805,7 @@ public class TestTransactionStore extends TestBase {
         MVStore s = MVStore.open(null);
 
         TransactionStore ts = new TransactionStore(s);
+        ts.init();
 
         Transaction tx;
         TransactionMap<String, String> m;