Issue 356: for Blob objects, InputStream.skip() returned 0, causing EOFException…

Issue 356: for Blob objects, InputStream.skip() returned 0, causing EOFException in Blob.getBytes(.., ..).

h2/src/main/org/h2/store/LobStorage.java

@@ -295,18 +295,20 @@ public class LobStorage {
         }
 
         public long skip(long n) throws IOException {
-            n -= skipSmall(n);
-            if (n > BLOCK_LENGTH) {
-                long toPos = length - remainingBytes + n;
+            long remaining = n;
+            remaining -= skipSmall(remaining);
+            if (remaining > BLOCK_LENGTH) {
+                long toPos = length - remainingBytes + remaining;
                 try {
                     long[] seqPos = skipBuffer(lob, toPos);
                     if (seqPos == null) {
-                        return super.skip(n);
+                        remaining -= super.skip(remaining);
+                        return n - remaining;
                     }
                     seq = (int) seqPos[0];
                     long p = seqPos[1];
                     remainingBytes = length - p;
-                    n = toPos - p;
+                    remaining = toPos - p;
                 } catch (SQLException e) {
                     throw DbException.convertToIOException(e);
                 }
@@ -314,8 +316,9 @@ public class LobStorage {
                 buffer = null;
             }
             fillBuffer();
-            n -= skipSmall(n);
-            return super.skip(n);
+            remaining -= skipSmall(remaining);
+            remaining -= super.skip(remaining);
+            return n - remaining;
         }
 
         private int skipSmall(long n) {

h2/src/test/org/h2/test/db/TestLob.java

@@ -55,6 +55,7 @@ public class TestLob extends TestBase {
     }
 
     public void test() throws Exception {
+        testLobSkip();
         testLobSkipPastEnd();
         testCreateIndexOnLob();
         testBlobInputStreamSeek(true);
@@ -101,6 +102,21 @@ public class TestLob extends TestBase {
         FileUtils.deleteRecursive(TEMP_DIR, true);
     }
 
+    private void testLobSkip() throws Exception {
+        deleteDb("lob");
+        Connection conn;
+        conn = getConnection("lob");
+        Statement stat = conn.createStatement();
+        stat.executeUpdate("create table test(x blob) as select secure_rand(1000)");
+        ResultSet rs = stat.executeQuery("select * from test");
+        rs.next();
+        Blob b = rs.getBlob(1);
+        byte[] test = b.getBytes(5 + 1, 1000 - 5);
+        assertEquals(1000 - 5, test.length);
+        stat.execute("drop table test");
+        conn.close();
+    }
+
     private void testLobSkipPastEnd() throws Exception {
         if (config.memory) {
             return;