Cache the stackframes to reduce the chatting between

GDB.

debug/org.eclipse.cdt.debug.mi.core/ChangeLog

@@ -1,3 +1,10 @@
+2004-12-22 Alain Magloire
+
+	Cache the stackframes when we become suspended, to reduce
+	the chat between gdb.
+
+	* src/org/eclipse/cdt/debug/mi/core/cdi/model/Thread.java
+
 2003-12-22 Mikhail Khodjaiants
 	Fix for bug 49282 terminate the gdb session if the termination of the inferior fails.
 

debug/org.eclipse.cdt.debug.mi.core/src/org/eclipse/cdt/debug/mi/core/cdi/model/Thread.java

@@ -5,6 +5,9 @@
  */
 package org.eclipse.cdt.debug.mi.core.cdi.model;
 
+import java.util.ArrayList;
+import java.util.List;
+
 import org.eclipse.cdt.debug.core.cdi.CDIException;
 import org.eclipse.cdt.debug.core.cdi.ICDILocation;
 import org.eclipse.cdt.debug.core.cdi.model.ICDISignal;
@@ -33,8 +36,11 @@ public class Thread extends CObject implements ICDIThread {
 	static ICDIStackFrame[] noStack = new ICDIStackFrame[0];
 	int id;
 	ICDIStackFrame currentFrame;
+	List currentFrames;
 	int stackdepth = 0;
 
+	final static int STACKFRAME_DEFAULT_DEPTH = 200;
+
 	public Thread(ICDITarget target, int threadId) {
 		super(target);
 		id = threadId;
@@ -47,6 +53,7 @@ public class Thread extends CObject implements ICDIThread {
 	public void clearState() {
 		stackdepth = 0;
 		currentFrame = null;
+		currentFrames = null;
 	}
 
 	public String toString() {
@@ -74,8 +81,13 @@ public class Thread extends CObject implements ICDIThread {
 	 * @see org.eclipse.cdt.debug.core.cdi.model.ICDIThread#getStackFrames()
 	 */
 	public ICDIStackFrame[] getStackFrames() throws CDIException {
-		int depth = 0;
+
-		ICDIStackFrame[] stacks = noStack;
+		// get the frames depth
+		int depth = getStackFrameCount();
+
+		// refresh if we have nothing or if we have just a subset get everything.
+		if (currentFrames == null || currentFrames.size() < depth) {
+			currentFrames = new ArrayList();
 			Session session = (Session) getTarget().getSession();
 			Target currentTarget = (Target) session.getCurrentTarget();
 			ICDIThread currentThread = currentTarget.getCurrentThread();
@@ -84,16 +96,14 @@ public class Thread extends CObject implements ICDIThread {
 				MISession mi = session.getMISession();
 				CommandFactory factory = mi.getCommandFactory();
 				MIStackListFrames frames = factory.createMIStackListFrames();
-			depth = getStackFrameCount();
 				mi.postCommand(frames);
 				MIStackListFramesInfo info = frames.getMIStackListFramesInfo();
 				if (info == null) {
 					throw new CDIException("No answer");
 				}
 				MIFrame[] miFrames = info.getMIFrames();
-			stacks = new StackFrame[miFrames.length];
+				for (int i = 0; i < miFrames.length; i++) {
-			for (int i = 0; i < stacks.length; i++) {
+					currentFrames.add(new StackFrame(this, miFrames[i], depth - miFrames[i].getLevel()));
-				stacks[i] = new StackFrame(this, miFrames[i], depth - miFrames[i].getLevel());
 				}
 			} catch (MIException e) {
 				//throw new CDIException(e.getMessage());
@@ -104,14 +114,17 @@ public class Thread extends CObject implements ICDIThread {
 			} finally {
 				currentTarget.setCurrentThread(currentThread, false);
 			}
+			// assign the currentFrame if it was not done yet.
 			if (currentFrame == null) {
-			for (int i = 0; i < stacks.length; i++) {
+				for (int i = 0; i < currentFrames.size(); i++) {
-				if (stacks[i].getLevel() == depth) {
+					ICDIStackFrame stack = (ICDIStackFrame) currentFrames.get(i);
-					currentFrame = stacks[i];
+					if (stack.getLevel() == depth) {
+						currentFrame = stack;
 					}
 				}
 			}
-		return stacks;
+		}
+		return (ICDIStackFrame[]) currentFrames.toArray(noStack);
 	}
 
 	/**
@@ -162,25 +175,35 @@ public class Thread extends CObject implements ICDIThread {
 	 * @see org.eclipse.cdt.debug.core.cdi.model.ICDIThread#getStackFrames()
 	 */
 	public ICDIStackFrame[] getStackFrames(int low, int high) throws CDIException {
-		ICDIStackFrame[] stacks = noStack;
+		if (currentFrames == null || currentFrames.size() < high) {
+			currentFrames = new ArrayList();
 			Session session = (Session) getTarget().getSession();
 			Target currentTarget = (Target) session.getCurrentTarget();
 			ICDIThread currentThread = currentTarget.getCurrentThread();
 			currentTarget.setCurrentThread(this, false);
 			try {
+				int depth = getStackFrameCount();
+				int upperBound;
+				// try to get the largest subset.
+				// if what the user asks is smaller then the depth
+				// try to cache things by getting the min(depth,STACKFRAME_DEFAULT_DEPTH)
+				// else give fetch the entire thing.
+				if (high < depth) {
+					upperBound = Math.min(depth, STACKFRAME_DEFAULT_DEPTH);
+				} else {
+					upperBound = depth;
+				}
 				MISession mi = session.getMISession();
 				CommandFactory factory = mi.getCommandFactory();
-			MIStackListFrames frames = factory.createMIStackListFrames(low, high);
+				MIStackListFrames frames = factory.createMIStackListFrames(0, upperBound);
-			int depth = getStackFrameCount();
 				mi.postCommand(frames);
 				MIStackListFramesInfo info = frames.getMIStackListFramesInfo();
 				if (info == null) {
 					throw new CDIException("No answer");
 				}
 				MIFrame[] miFrames = info.getMIFrames();
-			stacks = new StackFrame[miFrames.length];
+				for (int i = 0; i < miFrames.length; i++) {
-			for (int i = 0; i < stacks.length; i++) {
+					currentFrames.add(new StackFrame(this, miFrames[i], depth - miFrames[i].getLevel()));
-				stacks[i] = new StackFrame(this, miFrames[i], depth - miFrames[i].getLevel());
 				}
 			} catch (MIException e) {
 				//throw new CDIException(e.getMessage());
@@ -191,15 +214,18 @@ public class Thread extends CObject implements ICDIThread {
 			} finally {
 				currentTarget.setCurrentThread(currentThread, false);
 			}
+			// take time to assign the currentFrame, if it is in the set
 			if (currentFrame == null) {
-			for (int i = 0; i < stacks.length; i++) {
+				for (int i = 0; i < currentFrames.size(); i++) {
-				StackFrame f = (StackFrame)stacks[i];
+					StackFrame f = (StackFrame) currentFrames.get(i);
 					if (f.getMIFrame().getLevel() == 0) {
-					currentFrame = stacks[i];
+						currentFrame =f;
 					}
 				}
 			}
-		return stacks;
+		}
+		List list = currentFrames.subList(low, high);
+		return (ICDIStackFrame[])list.toArray(noStack);
 	}
 
 	/**