Implement non-wait co-operative termination of scripts for XEngine in addition to termination on wait.

This involves inserting opensim_reserved_CheckForCoopTermination() calls in lsl -> c# translation at any place where the script could be in a loop with no wait calls.
These places are for, while, do-while, label, user function call and manual event function call.
Call goes through to an XEngineScriptBase which extends ScriptBase.
IEngine is extended to supply necessary engine-specific parent class references and constructor parameters to Compiler.
Unfortunately, since XEngineScriptBase has to be passed WaitHandle in its constructor, older compiled scripts will fail to load with an error on the OpenSim console.
Such scripts will need to be recompiled, either by removing all *.dll files from the bin/ScriptEngines/<region-id> or by setting DeleteScriptsOnStartup = true in [XEngine] for one run.
Automatic recompilation may be implemented in a later commit.
This feature should not yet be used, default remains termination with Thread.Abort() which will work as normal once scripts are recompiled.

1 files changed, 88 insertions, 45 deletions

diff --git a/OpenSim/Region/ScriptEngine/Shared/CodeTools/CSCodeGenerator.cs b/OpenSim/Region/ScriptEngine/Shared/CodeTools/CSCodeGenerator.cs
index 97dd0f6..002f9b8 100644
--- a/OpenSim/Region/ScriptEngine/Shared/CodeTools/CSCodeGenerator.cs
+++ b/OpenSim/Region/ScriptEngine/Shared/CodeTools/CSCodeGenerator.cs
@@ -49,6 +49,18 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
         private List<string> m_warnings = new List<string>();
         private IScriptModuleComms m_comms = null;
 
+        private bool m_insertCoopTerminationChecks;
+        private static string m_coopTerminationCheck = "opensim_reserved_CheckForCoopTermination();";
+
+        /// <summary>
+        /// Keep a record of the previous node when we do the parsing.
+        /// </summary>
+        /// <remarks>
+        /// We do this here because the parser generated by CSTools does not retain a reference to its parent node.
+        /// The previous node is required so we can correctly insert co-op termination checks when required.
+        /// </remarks>
+//        private SYMBOL m_previousNode;
+
         /// <summary>
         /// Creates an 'empty' CSCodeGenerator instance.
         /// </summary>
@@ -58,9 +70,10 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
             ResetCounters();
         }
 
-        public CSCodeGenerator(IScriptModuleComms comms)
+        public CSCodeGenerator(IScriptModuleComms comms, bool insertCoopTerminationChecks)
         {
             m_comms = comms;
+            m_insertCoopTerminationChecks = insertCoopTerminationChecks;
             ResetCounters();
         }
 
@@ -155,7 +168,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
             // here's the payload
             retstr += GenerateLine();
             foreach (SYMBOL s in m_astRoot.kids)
-                retstr += GenerateNode(s);
+                retstr += GenerateNode(m_astRoot, s);
 
             // close braces!
             m_braceCount--;
@@ -165,7 +178,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
 
             // Removes all carriage return characters which may be generated in Windows platform. Is there
             // cleaner way of doing this?
-            retstr=retstr.Replace("\r", "");
+            retstr = retstr.Replace("\r", "");
 
             return retstr;
         }
@@ -191,9 +204,10 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
         /// Recursively called to generate each type of node. Will generate this
         /// node, then all it's children.
         /// </summary>
+        /// <param name="previousSymbol">The parent node.</param>
         /// <param name="s">The current node to generate code for.</param>
         /// <returns>String containing C# code for SYMBOL s.</returns>
-        private string GenerateNode(SYMBOL s)
+        private string GenerateNode(SYMBOL previousSymbol, SYMBOL s)
         {
             string retstr = String.Empty;
 
@@ -207,11 +221,11 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
             else if (s is State)
                 retstr += GenerateState((State) s);
             else if (s is CompoundStatement)
-                retstr += GenerateCompoundStatement((CompoundStatement) s);
+                retstr += GenerateCompoundStatement(previousSymbol, (CompoundStatement) s);
             else if (s is Declaration)
                 retstr += GenerateDeclaration((Declaration) s);
             else if (s is Statement)
-                retstr += GenerateStatement((Statement) s);
+                retstr += GenerateStatement(previousSymbol, (Statement) s);
             else if (s is ReturnStatement)
                 retstr += GenerateReturnStatement((ReturnStatement) s);
             else if (s is JumpLabel)
@@ -261,7 +275,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
             else
             {
                 foreach (SYMBOL kid in s.kids)
-                    retstr += GenerateNode(kid);
+                    retstr += GenerateNode(s, kid);
             }
 
             return retstr;
@@ -295,7 +309,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
             retstr += GenerateLine(")");
 
             foreach (SYMBOL kid in remainingKids)
-                retstr += GenerateNode(kid);
+                retstr += GenerateNode(gf, kid);
 
             return retstr;
         }
@@ -312,7 +326,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
             foreach (SYMBOL s in gv.kids)
             {
                 retstr += Indent();
-                retstr += GenerateNode(s);
+                retstr += GenerateNode(gv, s);
                 retstr += GenerateLine(";");
             }
 
@@ -365,7 +379,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
             retstr += GenerateLine(")");
 
             foreach (SYMBOL kid in remainingKids)
-                retstr += GenerateNode(kid);
+                retstr += GenerateNode(se, kid);
 
             return retstr;
         }
@@ -404,7 +418,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
 
             foreach (SYMBOL s in al.kids)
             {
-                retstr += GenerateNode(s);
+                retstr += GenerateNode(al, s);
                 if (0 < comma--)
                     retstr += Generate(", ");
             }
@@ -417,7 +431,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
         /// </summary>
         /// <param name="cs">The CompoundStatement node.</param>
         /// <returns>String containing C# code for CompoundStatement cs.</returns>
-        private string GenerateCompoundStatement(CompoundStatement cs)
+        private string GenerateCompoundStatement(SYMBOL previousSymbol, CompoundStatement cs)
         {
             string retstr = String.Empty;
 
@@ -425,8 +439,19 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
             retstr += GenerateIndentedLine("{");
             m_braceCount++;
 
+            if (m_insertCoopTerminationChecks)
+            {
+                // We have to check in event functions as well because the user can manually call these.
+                if (previousSymbol is GlobalFunctionDefinition 
+                    || previousSymbol is WhileStatement 
+                    || previousSymbol is DoWhileStatement 
+                    || previousSymbol is ForLoopStatement
+                    || previousSymbol is StateEvent)
+                retstr += GenerateIndentedLine(m_coopTerminationCheck);
+            }
+
             foreach (SYMBOL kid in cs.kids)
-                retstr += GenerateNode(kid);
+                retstr += GenerateNode(cs, kid);
 
             // closing brace
             m_braceCount--;
@@ -450,13 +475,24 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
         /// </summary>
         /// <param name="s">The Statement node.</param>
         /// <returns>String containing C# code for Statement s.</returns>
-        private string GenerateStatement(Statement s)
+        private string GenerateStatement(SYMBOL previousSymbol, Statement s)
         {
             string retstr = String.Empty;
             bool printSemicolon = true;
 
             retstr += Indent();
 
+            if (m_insertCoopTerminationChecks)
+            {
+                // We have to check in event functions as well because the user can manually call these.
+                if (previousSymbol is GlobalFunctionDefinition 
+                    || previousSymbol is WhileStatement 
+                    || previousSymbol is DoWhileStatement 
+                    || previousSymbol is ForLoop
+                    || previousSymbol is StateEvent)
+                retstr += Generate(m_coopTerminationCheck);
+            }
+
             if (0 < s.kids.Count)
             {
                 // Jump label prints its own colon, we don't need a semicolon.
@@ -466,7 +502,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
                 // (MONO) error.
                 if (!(s.kids.Top is IdentExpression && 1 == s.kids.Count))
                     foreach (SYMBOL kid in s.kids)
-                        retstr += GenerateNode(kid);
+                        retstr += GenerateNode(s, kid);
             }
 
             if (printSemicolon)
@@ -487,10 +523,10 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
             List<string> identifiers = new List<string>();
             checkForMultipleAssignments(identifiers, a);
 
-            retstr += GenerateNode((SYMBOL) a.kids.Pop());
+            retstr += GenerateNode(a, (SYMBOL) a.kids.Pop());
             retstr += Generate(String.Format(" {0} ", a.AssignmentType), a);
             foreach (SYMBOL kid in a.kids)
-                retstr += GenerateNode(kid);
+                retstr += GenerateNode(a, kid);
 
             return retstr;
         }
@@ -563,7 +599,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
             retstr += Generate("return ", rs);
 
             foreach (SYMBOL kid in rs.kids)
-                retstr += GenerateNode(kid);
+                retstr += GenerateNode(rs, kid);
 
             return retstr;
         }
@@ -575,7 +611,14 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
         /// <returns>String containing C# code for JumpLabel jl.</returns>
         private string GenerateJumpLabel(JumpLabel jl)
         {
-            return Generate(String.Format("{0}:", CheckName(jl.LabelName)), jl) + " NoOp();\n";
+            string labelStatement;
+
+            if (m_insertCoopTerminationChecks)
+                labelStatement = m_coopTerminationCheck + "\n";
+            else
+                labelStatement = "NoOp();\n";
+
+            return Generate(String.Format("{0}: ", CheckName(jl.LabelName)), jl) + labelStatement;
         }
 
         /// <summary>
@@ -598,14 +641,14 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
             string retstr = String.Empty;
 
             retstr += GenerateIndented("if (", ifs);
-            retstr += GenerateNode((SYMBOL) ifs.kids.Pop());
+            retstr += GenerateNode(ifs, (SYMBOL) ifs.kids.Pop());
             retstr += GenerateLine(")");
 
             // CompoundStatement handles indentation itself but we need to do it
             // otherwise.
             bool indentHere = ifs.kids.Top is Statement;
             if (indentHere) m_braceCount++;
-            retstr += GenerateNode((SYMBOL) ifs.kids.Pop());
+            retstr += GenerateNode(ifs, (SYMBOL) ifs.kids.Pop());
             if (indentHere) m_braceCount--;
 
             if (0 < ifs.kids.Count) // do it again for an else
@@ -614,7 +657,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
 
                 indentHere = ifs.kids.Top is Statement;
                 if (indentHere) m_braceCount++;
-                retstr += GenerateNode((SYMBOL) ifs.kids.Pop());
+                retstr += GenerateNode(ifs, (SYMBOL) ifs.kids.Pop());
                 if (indentHere) m_braceCount--;
             }
 
@@ -641,14 +684,14 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
             string retstr = String.Empty;
 
             retstr += GenerateIndented("while (", ws);
-            retstr += GenerateNode((SYMBOL) ws.kids.Pop());
+            retstr += GenerateNode(ws, (SYMBOL) ws.kids.Pop());
             retstr += GenerateLine(")");
 
             // CompoundStatement handles indentation itself but we need to do it
             // otherwise.
             bool indentHere = ws.kids.Top is Statement;
             if (indentHere) m_braceCount++;
-            retstr += GenerateNode((SYMBOL) ws.kids.Pop());
+            retstr += GenerateNode(ws, (SYMBOL) ws.kids.Pop());
             if (indentHere) m_braceCount--;
 
             return retstr;
@@ -669,11 +712,11 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
             // otherwise.
             bool indentHere = dws.kids.Top is Statement;
             if (indentHere) m_braceCount++;
-            retstr += GenerateNode((SYMBOL) dws.kids.Pop());
+            retstr += GenerateNode(dws, (SYMBOL) dws.kids.Pop());
             if (indentHere) m_braceCount--;
 
             retstr += GenerateIndented("while (", dws);
-            retstr += GenerateNode((SYMBOL) dws.kids.Pop());
+            retstr += GenerateNode(dws, (SYMBOL) dws.kids.Pop());
             retstr += GenerateLine(");");
 
             return retstr;
@@ -702,7 +745,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
             retstr += Generate("; ");
             // for (x = 0; x < 10; x++)
             //             ^^^^^^
-            retstr += GenerateNode((SYMBOL) fl.kids.Pop());
+            retstr += GenerateNode(fl, (SYMBOL) fl.kids.Pop());
             retstr += Generate("; ");
             // for (x = 0; x < 10; x++)
             //                     ^^^
@@ -713,7 +756,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
             // otherwise.
             bool indentHere = fl.kids.Top is Statement;
             if (indentHere) m_braceCount++;
-            retstr += GenerateNode((SYMBOL) fl.kids.Pop());
+            retstr += GenerateNode(fl, (SYMBOL) fl.kids.Pop());
             if (indentHere) m_braceCount--;
 
             return retstr;
@@ -758,7 +801,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
                 while (s is ParenthesisExpression)
                     s = (SYMBOL)s.kids.Pop();
                     
-                retstr += GenerateNode(s);
+                retstr += GenerateNode(fls, s);
                 if (0 < comma--)
                     retstr += Generate(", ");
             }
@@ -779,20 +822,20 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
             {
                 // special case handling for logical and/or, see Mantis 3174
                 retstr += "((bool)(";
-                retstr += GenerateNode((SYMBOL)be.kids.Pop());
+                retstr += GenerateNode(be, (SYMBOL)be.kids.Pop());
                 retstr += "))";
                 retstr += Generate(String.Format(" {0} ", be.ExpressionSymbol.Substring(0,1)), be);
                 retstr += "((bool)(";
                 foreach (SYMBOL kid in be.kids)
-                    retstr += GenerateNode(kid);
+                    retstr += GenerateNode(be, kid);
                 retstr += "))";
             }
             else
             {
-                retstr += GenerateNode((SYMBOL)be.kids.Pop());
+                retstr += GenerateNode(be, (SYMBOL)be.kids.Pop());
                 retstr += Generate(String.Format(" {0} ", be.ExpressionSymbol), be);
                 foreach (SYMBOL kid in be.kids)
-                    retstr += GenerateNode(kid);
+                    retstr += GenerateNode(be, kid);
             }
 
             return retstr;
@@ -808,7 +851,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
             string retstr = String.Empty;
 
             retstr += Generate(ue.UnarySymbol, ue);
-            retstr += GenerateNode((SYMBOL) ue.kids.Pop());
+            retstr += GenerateNode(ue, (SYMBOL) ue.kids.Pop());
 
             return retstr;
         }
@@ -824,7 +867,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
 
             retstr += Generate("(");
             foreach (SYMBOL kid in pe.kids)
-                retstr += GenerateNode(kid);
+                retstr += GenerateNode(pe, kid);
             retstr += Generate(")");
 
             return retstr;
@@ -861,7 +904,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
 
             // we wrap all typecasted statements in parentheses
             retstr += Generate(String.Format("({0}) (", te.TypecastType), te);
-            retstr += GenerateNode((SYMBOL) te.kids.Pop());
+            retstr += GenerateNode(te, (SYMBOL) te.kids.Pop());
             retstr += Generate(")");
 
             return retstr;
@@ -931,7 +974,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
             }
             
             foreach (SYMBOL kid in fc.kids)
-                retstr += GenerateNode(kid);
+                retstr += GenerateNode(fc, kid);
 
             retstr += Generate(")");
 
@@ -980,11 +1023,11 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
             string retstr = String.Empty;
 
             retstr += Generate(String.Format("new {0}(", vc.Type), vc);
-            retstr += GenerateNode((SYMBOL) vc.kids.Pop());
+            retstr += GenerateNode(vc, (SYMBOL) vc.kids.Pop());
             retstr += Generate(", ");
-            retstr += GenerateNode((SYMBOL) vc.kids.Pop());
+            retstr += GenerateNode(vc, (SYMBOL) vc.kids.Pop());
             retstr += Generate(", ");
-            retstr += GenerateNode((SYMBOL) vc.kids.Pop());
+            retstr += GenerateNode(vc, (SYMBOL) vc.kids.Pop());
             retstr += Generate(")");
 
             return retstr;
@@ -1000,13 +1043,13 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
             string retstr = String.Empty;
 
             retstr += Generate(String.Format("new {0}(", rc.Type), rc);
-            retstr += GenerateNode((SYMBOL) rc.kids.Pop());
+            retstr += GenerateNode(rc, (SYMBOL) rc.kids.Pop());
             retstr += Generate(", ");
-            retstr += GenerateNode((SYMBOL) rc.kids.Pop());
+            retstr += GenerateNode(rc, (SYMBOL) rc.kids.Pop());
             retstr += Generate(", ");
-            retstr += GenerateNode((SYMBOL) rc.kids.Pop());
+            retstr += GenerateNode(rc, (SYMBOL) rc.kids.Pop());
             retstr += Generate(", ");
-            retstr += GenerateNode((SYMBOL) rc.kids.Pop());
+            retstr += GenerateNode(rc, (SYMBOL) rc.kids.Pop());
             retstr += Generate(")");
 
             return retstr;
@@ -1024,7 +1067,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
             retstr += Generate(String.Format("new {0}(", lc.Type), lc);
 
             foreach (SYMBOL kid in lc.kids)
-                retstr += GenerateNode(kid);
+                retstr += GenerateNode(lc, kid);
 
             retstr += Generate(")");