LDEV-4696 - Feat/allow Lucee threads to cooperatively stop avoiding threadDeath in tomcat

core/src/main/java/lucee/commons/io/SystemUtil.java

@@ -1406,12 +1406,11 @@ public static void stop(PageContext pc, Thread thread) {
 	}
 
 	private static boolean _stop(Thread thread, Log log, boolean force) {
-		// we try to interrupt/stop the suspended thrad
+		// we try to interrupt/stop the suspended thread
 		suspendEL(thread);
 		try {
 			if (isInLucee(thread)) {
-				if (!force) thread.interrupt();
-				else thread.stop();
+				thread.interrupt();
 			}
 			else {
 				if (log != null) {

core/src/main/java/lucee/transformer/bytecode/statement/DoWhile.java

@@ -26,6 +26,7 @@
 import lucee.transformer.TransformerException;
 import lucee.transformer.bytecode.Body;
 import lucee.transformer.bytecode.BytecodeContext;
+import lucee.transformer.bytecode.util.InterruptHandlerInjector;
 import lucee.transformer.expression.ExprBoolean;
 import lucee.transformer.expression.Expression;
 
@@ -57,14 +58,18 @@ public DoWhile(Expression expr, Body body, Position start, Position end, String
 	@Override
 	public void _writeOut(BytecodeContext bc) throws TransformerException {
 		GeneratorAdapter adapter = bc.getAdapter();
+		final int loopCounter = InterruptHandlerInjector.writeLoopInit(adapter);
+
 		adapter.visitLabel(begin);
 		body.writeOut(bc);
 
+		InterruptHandlerInjector.writeLoopBodyEnd(adapter, loopCounter, beforeEnd, "during do while");
 		adapter.visitLabel(beforeEnd);
 
 		expr.writeOut(bc, Expression.MODE_VALUE);
 		adapter.ifZCmp(Opcodes.IFNE, begin);
 
+		InterruptHandlerInjector.writePreempt(adapter, end, "after do while");
 		adapter.visitLabel(end);
 
 	}

core/src/main/java/lucee/transformer/bytecode/statement/For.java

@@ -28,6 +28,7 @@
 import lucee.transformer.bytecode.Body;
 import lucee.transformer.bytecode.BytecodeContext;
 import lucee.transformer.bytecode.util.ASMUtil;
+import lucee.transformer.bytecode.util.InterruptHandlerInjector;
 import lucee.transformer.expression.Expression;
 
 public final class For extends StatementBaseNoFinal implements FlowControlBreak, FlowControlContinue, HasBody {
@@ -69,6 +70,7 @@ public void _writeOut(BytecodeContext bc) throws TransformerException {
 		Label beforeInit = new Label();
 		Label afterInit = new Label();
 		Label afterUpdate = new Label();
+		final int loopCounter = InterruptHandlerInjector.writeLoopInit(adapter);
 
 		bc.visitLine(getStart());
 		adapter.visitLabel(beforeInit);
@@ -87,13 +89,16 @@ public void _writeOut(BytecodeContext bc) throws TransformerException {
 			update.writeOut(bc, Expression.MODE_VALUE);
 			ASMUtil.pop(adapter, update, Expression.MODE_VALUE);
 		}
+
+		InterruptHandlerInjector.writeLoopBodyEnd(adapter, loopCounter, afterUpdate, "during for loop");
 		// ExpressionUtil.visitLine(bc, getStartLine());
 		adapter.visitLabel(afterUpdate);
 
 		if (condition != null) condition.writeOut(bc, Expression.MODE_VALUE);
 		else bc.getFactory().TRUE().writeOut(bc, Expression.MODE_VALUE);
 		adapter.visitJumpInsn(Opcodes.IFNE, afterInit);
 		// ExpressionUtil.visitLine(bc, getEndLine());
+		InterruptHandlerInjector.writePreempt(adapter, end, "after for loop");
 		adapter.visitLabel(end);
 
 	}

core/src/main/java/lucee/transformer/bytecode/statement/ForEach.java

@@ -31,6 +31,7 @@
 import lucee.transformer.bytecode.BytecodeContext;
 import lucee.transformer.bytecode.expression.var.VariableRef;
 import lucee.transformer.bytecode.util.Types;
+import lucee.transformer.bytecode.util.InterruptHandlerInjector;
 import lucee.transformer.bytecode.visitor.OnFinally;
 import lucee.transformer.bytecode.visitor.TryFinallyVisitor;
 import lucee.transformer.expression.Expression;
@@ -81,6 +82,7 @@ public void _writeOut(BytecodeContext bc) throws TransformerException {
 		GeneratorAdapter adapter = bc.getAdapter();
 		final int it = adapter.newLocal(Types.ITERATOR);
 		final int item = adapter.newLocal(Types.REFERENCE);
+		final int loopCounter = InterruptHandlerInjector.writeLoopInit(adapter);
 
 		// Value
 		// ForEachUtil.toIterator(value)
@@ -130,7 +132,7 @@ public void _writeOut(BytecodeContext bc) throws TransformerException {
 
 		// Body
 		body.writeOut(bc);
-		adapter.visitJumpInsn(Opcodes.GOTO, begin);
+		InterruptHandlerInjector.writeLoopBodyEnd(adapter, loopCounter, begin, "during foreach loop");
 		adapter.visitLabel(end);
 		tfv.visitTryEnd(bc);
 

core/src/main/java/lucee/transformer/bytecode/statement/While.java

@@ -26,6 +26,7 @@
 import lucee.transformer.TransformerException;
 import lucee.transformer.bytecode.Body;
 import lucee.transformer.bytecode.BytecodeContext;
+import lucee.transformer.bytecode.util.InterruptHandlerInjector;
 import lucee.transformer.expression.ExprBoolean;
 import lucee.transformer.expression.Expression;
 
@@ -67,13 +68,14 @@ public While(boolean b, Body body, Position start, Position end, String label) {
 	@Override
 	public void _writeOut(BytecodeContext bc) throws TransformerException {
 		GeneratorAdapter adapter = bc.getAdapter();
+		final int loopCounter = InterruptHandlerInjector.writeLoopInit(adapter);
 		adapter.visitLabel(begin);
 
 		expr.writeOut(bc, Expression.MODE_VALUE);
 		adapter.ifZCmp(Opcodes.IFEQ, end);
 
 		body.writeOut(bc);
-		adapter.visitJumpInsn(Opcodes.GOTO, begin);
+		InterruptHandlerInjector.writeLoopBodyEnd(adapter, loopCounter, begin, "during while loop");
 
 		adapter.visitLabel(end);
 	}

core/src/main/java/lucee/transformer/bytecode/util/InterruptHandlerInjector.java

@@ -0,0 +1,54 @@
+/**
+ * The goal of this helper is mostly to add a hooked bytecode to allow safe interruption of threads avoiding
+ * Tomcat ThreadDeath and the thread.stop() codepath
+ */
+package lucee.transformer.bytecode.util;
+
+import org.objectweb.asm.Label;
+import org.objectweb.asm.Opcodes;
+import org.objectweb.asm.Type;
+
+import org.objectweb.asm.commons.GeneratorAdapter;
+import org.objectweb.asm.commons.Method;
+import lucee.transformer.bytecode.util.Types;
+
+public final class InterruptHandlerInjector {
+	private static final Type TYPE_THREAD = Type.getType(Thread.class);
+	private static final Type TYPE_EXCEPTION = Type.getType(InterruptedException.class);
+	private static final Method METHOD_INTERRUPTED = new Method("interrupted", Type.BOOLEAN_TYPE, new Type[] {});
+
+	public static int writeLoopInit(GeneratorAdapter adapter) {
+		final int toIt = adapter.newLocal(Types.ITERATOR);
+		adapter.push(0);
+		adapter.storeLocal(toIt, Type.INT_TYPE);
+		return toIt;
+	}
+
+	public static void writeLoopBodyEnd(GeneratorAdapter adapter, int iteratorRef, Label jumpLabel, String timeoutDescription) {
+		// count the loop, only check for interruptions once every 10K iterations
+		adapter.iinc(iteratorRef, 1);
+		adapter.loadLocal(iteratorRef);
+		adapter.push(10000);
+		adapter.ifICmp(Opcodes.IFLT, jumpLabel);
+		// reset counter
+		adapter.push(0);
+		adapter.storeLocal(iteratorRef);
+		// Check if the thread is interrupted
+		writePreempt(adapter, jumpLabel, timeoutDescription);
+	}
+
+	public static void writeEndPreempt(GeneratorAdapter adapter, String timeoutDescription) {
+		Label endPreempt = new Label();
+		writePreempt(adapter, endPreempt, timeoutDescription);
+		adapter.visitLabel(endPreempt);
+	}
+
+	public static void writePreempt(GeneratorAdapter adapter, Label label, String timeoutDescription) {
+		// Check if the thread is interrupted
+		adapter.invokeStatic(TYPE_THREAD, METHOD_INTERRUPTED);
+		// Thread hasn't been interrupted, go to endPreempt
+		adapter.ifZCmp(Opcodes.IFEQ, label);
+		// Thread interrupted, throw Interrupted Exception
+		adapter.throwException(TYPE_EXCEPTION, "Timeout Exception ".concat(timeoutDescription));
+	}
+}

core/src/main/java/lucee/transformer/bytecode/visitor/DoWhileVisitor.java

@@ -23,6 +23,7 @@
 import org.objectweb.asm.commons.GeneratorAdapter;
 
 import lucee.transformer.bytecode.BytecodeContext;
+import lucee.transformer.bytecode.util.InterruptHandlerInjector;
 
 // TODO testen wurde noch nicht getestet
 
@@ -31,21 +32,25 @@ public final class DoWhileVisitor implements LoopVisitor {
 	private Label begin;
 	private Label end;
 	private Label beforeEnd;
+	private int loopCounter;
 
 	public void visitBeginBody(GeneratorAdapter mv) {
 		end = new Label();
 		beforeEnd = new Label();
 
 		begin = new Label();
+		loopCounter = InterruptHandlerInjector.writeLoopInit(mv);
 		mv.visitLabel(begin);
 	}
 
 	public void visitEndBodyBeginExpr(GeneratorAdapter mv) {
+		InterruptHandlerInjector.writeLoopBodyEnd(mv, loopCounter, beforeEnd, "during do while");
 		mv.visitLabel(beforeEnd);
 	}
 
 	public void visitEndExpr(GeneratorAdapter mv) {
 		mv.ifZCmp(Opcodes.IFNE, begin);
+		InterruptHandlerInjector.writePreempt(mv, end, "after do while");
 		mv.visitLabel(end);
 	}
 

core/src/main/java/lucee/transformer/bytecode/visitor/ForDoubleVisitor.java

@@ -25,6 +25,7 @@
 import lucee.transformer.Position;
 import lucee.transformer.bytecode.BytecodeContext;
 import lucee.transformer.bytecode.util.Types;
+import lucee.transformer.bytecode.util.InterruptHandlerInjector;
 
 public final class ForDoubleVisitor implements Opcodes, LoopVisitor {
 
@@ -33,9 +34,11 @@ public final class ForDoubleVisitor implements Opcodes, LoopVisitor {
 	public Label beforeBody = new Label(), afterBody = new Label();
 	public Label beforeUpdate = new Label(), afterUpdate = new Label();
 	public int i;
+	private int loopCounter;
 
 	public int visitBeforeExpression(GeneratorAdapter adapter, int start, int step, boolean isLocal) {
 		// init
+		loopCounter = InterruptHandlerInjector.writeLoopInit(adapter);
 		adapter.visitLabel(beforeInit);
 		forInit(adapter, start, isLocal);
 		adapter.goTo(beforeExpr);
@@ -75,6 +78,8 @@ public void forUpdate(GeneratorAdapter adapter, int step, boolean isLocal) {
 			adapter.visitVarInsn(DSTORE, i);
 		}
 		else adapter.visitIincInsn(i, step);
+
+		InterruptHandlerInjector.writeLoopBodyEnd(adapter, loopCounter, beforeExpr, "during for loop");
 	}
 
 	/**

core/src/main/java/lucee/transformer/bytecode/visitor/ForIntVisitor.java

@@ -25,6 +25,7 @@
 import lucee.transformer.Position;
 import lucee.transformer.bytecode.BytecodeContext;
 import lucee.transformer.bytecode.util.Types;
+import lucee.transformer.bytecode.util.InterruptHandlerInjector;
 
 public final class ForIntVisitor implements Opcodes, LoopVisitor {
 
@@ -33,9 +34,11 @@ public final class ForIntVisitor implements Opcodes, LoopVisitor {
 	private Label beforeBody = new Label(), afterBody = new Label();
 	private Label beforeUpdate = new Label(), afterUpdate = new Label();
 	private int i;
+	private int loopCounter;
 
 	public int visitBeforeExpression(GeneratorAdapter adapter, int start, int step, boolean isLocal) {
 		// init
+		loopCounter = InterruptHandlerInjector.writeLoopInit(adapter);
 		adapter.visitLabel(beforeInit);
 		forInit(adapter, start, isLocal);
 		adapter.goTo(beforeExpr);
@@ -75,6 +78,8 @@ private void forUpdate(GeneratorAdapter adapter, int step, boolean isLocal) {
 			adapter.visitVarInsn(ISTORE, i);
 		}
 		else adapter.visitIincInsn(i, step);
+
+		InterruptHandlerInjector.writeLoopBodyEnd(adapter, loopCounter, beforeExpr, "during for loop");
 	}
 
 	/**

core/src/main/java/lucee/transformer/bytecode/visitor/ForVisitor.java

@@ -25,6 +25,7 @@
 import lucee.transformer.Position;
 import lucee.transformer.bytecode.BytecodeContext;
 import lucee.transformer.bytecode.util.Types;
+import lucee.transformer.bytecode.util.InterruptHandlerInjector;
 
 public final class ForVisitor implements Opcodes, LoopVisitor {
 
@@ -35,8 +36,11 @@ public final class ForVisitor implements Opcodes, LoopVisitor {
 	private int i;
 	private Label lend = new Label();
 	private Label lbegin = new Label();
+	private int loopCounter;
 
 	public int visitBegin(GeneratorAdapter adapter, int start, boolean isLocal) {
+		loopCounter = InterruptHandlerInjector.writeLoopInit(adapter);
+
 		adapter.visitLabel(l0);
 
 		forInit(adapter, start, isLocal);
@@ -77,6 +81,8 @@ private void forInit(GeneratorAdapter adapter, int start, boolean isLocal) {
 		if (isLocal) adapter.loadLocal(start);
 		else adapter.push(start);
 		adapter.visitVarInsn(ISTORE, i);
+
+		InterruptHandlerInjector.writeLoopBodyEnd(adapter, loopCounter, l1, "during for loop");
 	}
 
 	/**

core/src/main/java/lucee/transformer/bytecode/visitor/WhileVisitor.java

@@ -23,16 +23,19 @@
 
 import lucee.transformer.Position;
 import lucee.transformer.bytecode.BytecodeContext;
+import lucee.transformer.bytecode.util.InterruptHandlerInjector;
 
 public final class WhileVisitor implements LoopVisitor {
 
 	private Label begin;
 	private Label end;
+	private int loopCounter;
 
 	public void visitBeforeExpression(BytecodeContext bc) {
 		begin = new Label();
 		end = new Label();
 		bc.getAdapter().visitLabel(begin);
+		loopCounter = InterruptHandlerInjector.writeLoopInit(bc.getAdapter());
 	}
 
 	public void visitAfterExpressionBeforeBody(BytecodeContext bc) {
@@ -41,6 +44,8 @@ public void visitAfterExpressionBeforeBody(BytecodeContext bc) {
 
 	public void visitAfterBody(BytecodeContext bc, Position endline) {
 		bc.getAdapter().visitJumpInsn(Opcodes.GOTO, begin);
+
+		InterruptHandlerInjector.writeLoopBodyEnd(bc.getAdapter(), loopCounter, end, "during while loop");
 		bc.getAdapter().visitLabel(end);
 		bc.visitLine(endline);
 	}