Introspective Debugger — the basic structure

So the first thing that this script does is decide which instance of the script it is. What I mean by this that this page now loads completely diffrent code and behaves differently depending on what the situation is.So by default when you load the page, its going to generate an ID number (which will be used as a high port), load a very simple frameset, and then die

if(!array_key_exists("idbg_mode",$_GET)){ /* Display Frame Mode */ echo("<html> <frameset rows='65%,35%'> <frame src='$callBackName"."cnc' name='infoframe'> <frame src='$callBackWvars"."run' name='scriptframe'></frameset></html>"); exit();

each of the two frames within the frame set then calls the same script, but passes variables to it that drastically change its behaviorOne of them calls with the cnc option (command and control) and one of them calls with the run option, which tells the program to go ahead and run, with the degbugging code active.In each case, the instances are passed (as a get variable) the instance id that was generated with the frameset, which is how they know what port to find eachother on.

I’ll go into how CNC works, and how the processes talk to eachother a good bit more in later posts, but for now I want to look at how the “run” instance works. Run depends on a very obscure php language feature called “register_tick_function” which allows you to set a function that will be run every X statements that are addition to registering the tick function it is necessary to start the ticks firing by using the line declare(ticks=1);Honestly I’m a little curious why this languge feature is in PHP at all, but its there, So I think I might as well use it. This is also the feature that was the inspiration for the whole damn project.So the very Astute among you might notice that I do not ever actually call declare(ticks=1), but instead require the user to put it in there code right after they include my file, which is horribly inelegant. Why you might ask?As it turns out the declare statement (possibly only with refrence to ticks, but ticks are the ONLY thing that you can use the declare statement for currently, I guess we will find out if this is universal when we move on to php6) seems to only apply to includes at the same depth and lower in the file inclusion tree as it.This means that since you are including my file in your file, my file is at depth 2 and your file is at depth 1, if I put the declare statement in my file, it will not apply to your file, though it will start applying to any other files that you include. This problem is not documented, and honestly drove me batty for a good long time, because it generates such strange behavior.

else if (array_key_exists("idbg_mode",$_GET) && $_GET["idbg_mode"] == "run"){
echo ("<h1> I am running DIV $idbg_id </h1>"); register_tick_function("idbg_tick_function");}
I need to cover a lot more of what happens at each tick, but I want to keep each post pretty short, so I’m going to save that for tomorrow.In the meantime I should try to get some paid work done.

One thought on “Introspective Debugger — the basic structure”

  1. Wow, wordpress deals really poorly with having code posted to it. :/ Gonna need to work something out regarding that.

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