From 88119eb1eaa6c873fd7e7e963f46b8a1cb3a3ac4 Mon Sep 17 00:00:00 2001
From: Marc Khouzam <marc.khouzam@ericsson.com>
Date: Tue, 13 May 2008 19:59:14 +0000
Subject: [PATCH] Bug 223386 Improve the variableObjectId to use contexts for
 comparison.  The value of this approach is that it is future proof no matter
 how many levels of container contexts are used later on.

---
 .../dd/mi/service/MIVariableManager.java      | 37 +++++++------------
 1 file changed, 14 insertions(+), 23 deletions(-)

diff --git a/plugins/org.eclipse.dd.mi/src/org/eclipse/dd/mi/service/MIVariableManager.java b/plugins/org.eclipse.dd.mi/src/org/eclipse/dd/mi/service/MIVariableManager.java
index fb064a97a11..a5616efb70a 100644
--- a/plugins/org.eclipse.dd.mi/src/org/eclipse/dd/mi/service/MIVariableManager.java
+++ b/plugins/org.eclipse.dd.mi/src/org/eclipse/dd/mi/service/MIVariableManager.java
@@ -35,6 +35,7 @@ import org.eclipse.dd.dsf.debug.service.IExpressions.IExpressionDMContext;
 import org.eclipse.dd.dsf.debug.service.IFormattedValues.FormattedValueDMContext;
 import org.eclipse.dd.dsf.debug.service.IFormattedValues.FormattedValueDMData;
 import org.eclipse.dd.dsf.debug.service.IMemory.IMemoryChangedEvent;
+import org.eclipse.dd.dsf.debug.service.IRunControl.IExecutionDMContext;
 import org.eclipse.dd.dsf.debug.service.IStack.IFrameDMContext;
 import org.eclipse.dd.dsf.debug.service.command.ICommand;
 import org.eclipse.dd.dsf.debug.service.command.ICommandControl;
@@ -1154,16 +1155,19 @@ public class MIVariableManager implements ICommandControl {
 	 * 
 	 * The following must be considered to obtain a unique name:
 	 *     - the expression itself
-	 *     - the threadId specified in the execution context 
+	 *     - the execution context 
 	 *     - relative depth of frame based on the frame context and the total depth of the stack
 	 *     
 	 * Note that if no frameContext is specified (only Execution, or even only Container), which can
 	 * characterize a global variable for example, we will only use the available information.
 	 */
 	private class VariableObjectId {
+		// We don't use the expression context because it is not safe to compare them
+		// See bug 187718.  So we store the expression itself, and it's parent execution context.
 		String fExpression = null;
-		String fControlId = null;
-		Integer fThreadId = null;
+		IExecutionDMContext fExecContext = null;
+		// We need the depth of the frame.  The frame level is not sufficient because 
+        // the same frame will have a different level based on the current depth of the stack 
 		Integer fFrameId = null;
 		
 		@Override
@@ -1171,8 +1175,7 @@ public class MIVariableManager implements ICommandControl {
 			if (other instanceof VariableObjectId) {
 				VariableObjectId otherId = (VariableObjectId) other;
 				return (fExpression == null ? otherId.fExpression == null : fExpression.equals(otherId.fExpression)) &&
-    				(fControlId == null ? otherId.fControlId == null : fControlId.equals(otherId.fControlId)) &&
-    				(fThreadId == null ? otherId.fThreadId == null : fThreadId.equals(otherId.fThreadId)) &&
+    				(fExecContext == null ? otherId.fExecContext == null : fExecContext.equals(otherId.fExecContext)) &&
                     (fFrameId == null ? otherId.fFrameId == null : fFrameId.equals(otherId.fFrameId));
 			}
 			return false;
@@ -1181,30 +1184,19 @@ public class MIVariableManager implements ICommandControl {
 		@Override
 		public int hashCode() {
 			return (fExpression == null ? 0 : fExpression.hashCode()) + 
-		           (fControlId == null ? 0 : fControlId.hashCode()) +
-		           (fThreadId == null ? 0 : fThreadId.hashCode()) +
+		           (fExecContext == null ? 0 : fExecContext.hashCode()) +
 			       (fFrameId  == null ? 0 : fFrameId.hashCode());
 		}
 
 		public void generateId(IExpressionDMContext exprCtx, final RequestMonitor rm) {
 			fExpression = exprCtx.getExpression();
 
-			MIControlDMContext controlCtx = DMContexts.getAncestorOfType(exprCtx, MIControlDMContext.class);
-			if (controlCtx == null) {
-				rm.done();
-				return;
-			}
-
-			fControlId = controlCtx.getCommandControlFilter();
-
-			IMIExecutionDMContext execCtx = DMContexts.getAncestorOfType(exprCtx, IMIExecutionDMContext.class);
-			if (execCtx == null) {
+			fExecContext = DMContexts.getAncestorOfType(exprCtx, IExecutionDMContext.class);
+			if (fExecContext == null) {
 				rm.done();
 				return;
 			}
 			
-			fThreadId = new Integer(execCtx.getThreadId());
-
 			final IFrameDMContext frameCtx = DMContexts.getAncestorOfType(exprCtx, IFrameDMContext.class);
 			if (frameCtx == null) {
 				rm.done();
@@ -1215,7 +1207,7 @@ public class MIVariableManager implements ICommandControl {
 			// for this expression.  This is pretty efficient since the stackDepth will be retrieved
 			// from the StackService command cache after the first time.
 			fStackService.getStackDepth(
-					execCtx, 0,
+					fExecContext, 0,
 					new DataRequestMonitor<Integer>(fSession.getExecutor(), rm) {
 						@Override
 						protected void handleSuccess() {
@@ -1226,9 +1218,8 @@ public class MIVariableManager implements ICommandControl {
 		}
 		
 		public void generateId(String childFullExp, VariableObjectId parentId) {
-			// The control, thread and frame are the same as the parent
-			fControlId = parentId.fControlId;
-			fThreadId = parentId.fThreadId;
+			// The execution context and the frame depth are the same as the parent
+			fExecContext = parentId.fExecContext;
 			fFrameId = parentId.fFrameId;
 			// The expression here must be the one that is part of IExpressionContext for this child
 			// This will allow us to find a variable object directly