Subj : finilize & construct: call disbalance
To   : netscape.public.mozilla.jseng
From : anton muhin
Date : Thu Jul 08 2004 05:18 pm

Hello, everybody!

First of all, thank you for SpiderMonkey product --- it's really good.

The problem: I have a problem with misbalanced calls of constructor and 
finilizers.

Details: I extend JavaScript with a class that in construction allocates 
some private data and sets them to the object. In the finilizer I free 
these data. The JavaScript session is really simple:

js> var c = new MyClass()
js> quit()

With the session my constructor (in C) is called once. However, the 
finilizer (in C also) is called three times and it's only the last time 
when it gets called with the object created in the constructor. Is it 
normal or I do something stupid?

Abridged versions of the constructor and finilizer (all the checks removed):

JSBool
my_constructor(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, 
jsval *rval)
{
     JSObject * o = JS_NewObject(cx, &kls, NULL, NULL);

     void * data = malloc(SIZE);

     JS_SetPrivate(cx, o, data);

     *rval = OBJECT_TO_JSVAL(o);
     return JS_TRUE;
}

void
my_finalize(JSContext *cx, JSObject *obj)
{
     void * data = JS_GetPrivate(cx, obj);
     free(data);
}

thank you for your time,
anton.

.