Subj : Re: Stopping Script Execution
To   : netscape.public.mozilla.jseng
From : Brendan Eich <brendan@meer.net>
Date : Wed Sep 24 2003 11:42 pm

Damian Slee wrote:

> initialisation
> 	JS_SetBranchCallback(m_Context, BranchCallback);
> 
> callback
> #define SCRIPT_TIMEOUT 3000
> 
> JSBool BranchCallback(JSContext *Context, JSScript *Script)
> {
> 	JSObject *global = JS_GetGlobalObject(Context);
> 	if (global)
> 	{
> 			if (m_scriptTimer.Expired(SCRIPT_TIMEOUT))
> 			{
> 				JS_ReportError(Context,"Script execution halted, possible infinite loop");
> 				return JS_FALSE;
> 			}
> 		}
> 	}
> 
>     return JS_TRUE;
> }
> 

You don't show what m_scriptTimer looks like.

It's best to keep the branch callback a leaf function that tests an 
unsigned counter mod a power of two.  Remember that it will be called on 
*every* backward branch and return statement, so it should be as fast as 
possible.

/be

.