XPCOM in JavaScript, launchFunctionW?

Question

I studied in an open-source Firefox plugin, I wanted to know what action does the following code snippet. I knew nothing of the code??

enter: function()
        {
            if (this.xpcomObject != undefined || this.createXPCOMObject())
                this.xpcomObject.launchFunctionW("enter", "", "", "");
        },

It is not very much to go on. It is very hard to tell what magic is supposed to happen here, based on just three lines of code. — Werner Kvalem Vesterås, Dec 29 '12 at 11:42
@WernerVesterås my problem is just xpcomObject.launchFunctionW Function. complete source is long. — HamiD, Dec 30 '12 at 11:24

score 0 · Answer 1 · answered Dec 30 '12 at 19:01

Searching the Mozilla source code for "launchFunctionW" yields zero results (see http://mxr.mozilla.org/comm-central/search?string=launchfunctionw&filter=^[^\0]*%24&tree=comm-central for an attempt to do just that). Therefore, this function is likely to be defined by your addon.

From the naming of the function and the presence of an XPCOM object, I suspect this function may just be written in C++. Is there a binary object lying around? Do you have the source for it? Have you tried grepping the source directory for "launchFunctionW"?

It's very hard to help you with such scarce information...

XPCOM in JavaScript, launchFunctionW?

1 Answers1