Add version marker to fail fast if people try and load AOT/persisted …

…files across releases
jruby · Jul 15, 2015 · b81d689 · b81d689
1 parent 753b92f
commit b81d689
Showing 3 changed files with 10 additions and 5 deletions.
diff --git a/core/src/main/java/org/jruby/ir/persistence/IRPersistenceValues.java b/core/src/main/java/org/jruby/ir/persistence/IRPersistenceValues.java
@@ -13,6 +13,7 @@
  * @author enebo
  */
 interface IRPersistenceValues {
+    public static final int VERSION = 1;
     public final static int TWO_MEGS = 1024 * 1024 * 2;
 
     // Operands and primitive values can be mixed together
@@ -29,7 +30,7 @@ interface IRPersistenceValues {
     public final static byte DOUBLE = (byte) (PRIMITIVE_BASE + 10);
     public final static byte FULL = (byte) 255;
 
-    public final static int PROLOGUE_LENGTH = 2 * 4; // 2 ints at front
+    public final static int PROLOGUE_LENGTH = 3 * 4; // 3 raw ints {version, scope_offset, pool_offset}
 
     public final static int NULL_STRING = -1;
 }
diff --git a/core/src/main/java/org/jruby/ir/persistence/IRReader.java b/core/src/main/java/org/jruby/ir/persistence/IRReader.java
@@ -13,7 +13,6 @@
 import org.jruby.ir.operands.LocalVariable;
 import org.jruby.parser.StaticScope;
 import org.jruby.parser.StaticScopeFactory;
-import org.jruby.runtime.Arity;
 import org.jruby.runtime.Signature;
 
 import java.io.IOException;
@@ -25,8 +24,14 @@
  *
  * @author enebo
  */
-public class IRReader {
+public class IRReader implements IRPersistenceValues {
     public static IRScope load(IRManager manager, IRReaderDecoder file) throws IOException {
+        int version = file.decodeIntRaw();
+
+        if (version != VERSION) {
+            throw new IOException("Trying to read incompatable persistence format (version found: " +
+                    version + ", version expected: " + VERSION);
+        }
         int headersOffset = file.decodeIntRaw();
         if (RubyInstanceConfig.IR_READING_DEBUG) System.out.println("header_offset = " + headersOffset);
         int poolOffset = file.decodeIntRaw();

diff --git a/core/src/main/java/org/jruby/ir/persistence/IRWriterStream.java b/core/src/main/java/org/jruby/ir/persistence/IRWriterStream.java
@@ -33,8 +33,6 @@
  * Represents a file which is persisted to storage.
  */
 public class IRWriterStream implements IRWriterEncoder, IRPersistenceValues {
-    private static final int VERSION = 0;
-
     private final Map<IRScope, Integer> scopeInstructionOffsets = new HashMap<>();
     // FIXME: Allocate direct and use one per thread?
     private final ByteBuffer buf = ByteBuffer.allocate(TWO_MEGS);
@@ -260,6 +258,7 @@ public void startEncoding(IRScope script) {
     @Override
     public void endEncoding(IRScope script) {
         try {
+            stream.write(ByteBuffer.allocate(4).putInt(VERSION).array());
             stream.write(ByteBuffer.allocate(4).putInt(headersOffset).array());
             stream.write(ByteBuffer.allocate(4).putInt(poolOffset).array());
             buf.flip();