NoshBar's Dumping Ground




Ever had one of those folders that doesn't technically belong to you and -even though you've got Administrator rights- you can't delete it?

The usual way is to right-click the folder, select security, click advanced, change the owner of it and all subitems to you, then accept, then right-click and open it again so that you can grant full rights on the folder to you...

Well, say now you want to do this for a bunch of folders, say an existing Windows installation on a drive you're using from within a newer Windows installation... it's a huge pain in the gluteus maximus.

Why not Zoidberg a DOS batch file?
takeown /F %1\* /R /A
icacls %1\*.* /T /grant administrators:F
rmdir /S /Q %1

Example usage: deleteit.bat e:\windows

Note: if icacls is not available, try just cacls which also works, but first prompts you if you're sure.

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Or to be quite silly:
Delphi Web Scripting in a Dynamic Link Library for running Object Pascal scripts in C [and other languages]

What it is.


This is a simple Windows DLL (32-bit DLL provided) that enables you to compile and run Object Pascal scripts from within your favourite language (provided it supports loading DLL's with the stdcall calling convention) using the DWScript engine by Eric Grange.

Support for calling functions in the Pascal script is supported, as well as registering functions from e.g., C that the script can call. (A sample C wrapper and example are included in the "c_interface" folder).

Available under the Mozilla Public License 1.1

Why? Who can honestly say they've never wanted to run hand-optimised assembler inlined into Pascal Script from within Visual Basic 6? I know I have.

Features.


  • Run full Object Pascal scripts from within your application
  • Jitter can be enabled for JIT compilation, speeding up code "quite a lot".
    I obtained nearly double the execution performance in some cases e.g, running my smallPT renderer conversion without JIT enabled took 39 seconds, whereas the JIT enabled one only took 25 seconds.
    [*only when compiled with Delphi for now]
  • OLE support can be enabled
    [*only when compiled with Delphi for now]
  • ASM support can be enabled
    [*requires NASM executable in the same path as the DLL]
  • The provided DLL was built using Delphi XE 5 from an SVN checkout of the DWScript sources on the 18th of April 2014.


Using.


A simple C example would be something like this:
HMODULE handle = DWScript_initialise("dwscript.dll");  
//you can make as many contexts as you like, but cannot mix and match contexts as you wish
DWScriptContext context = DWScript_createContext(DWScript_Flags_Ole | DWScript_Flags_Asm);
//add any local C functions into the context with DWScript_addFunction()
//and DWScript_addParameter() before compiling
DWScript_compile(context, "begin end.", DWScript_Flags_Jitter); //only necessary once per context
DWScript_execute(context, DWScript_Flags_None); //call as many times as you like
DWScript_destroyContext(context);
DWScript_finalise(handle);


Ideas / TODO


  • Instead of the horrendous fixed-array of unions parameter nonsense going on, you could optionally make the functions take varargs and make calling them a much-more straight-forward affair.
    My only worry then is that you'd have to change from stdcall to cdecl, thereby losing the ability to use this DLL from within certain languages.
  • Fix Unicode/AnsiString conversions / Implement Unicode support
  • Add the ability to run a script in a non-blocking manner.
  • Add debugger support so that you can set breakpoints in the code, etc.
  • Make error handling and reporting not suck.


Free Pascal Notes.


TL;DR; Only this binary collection of FPC 2.7.1 works for me.

I initially started this project using Free Pascal.

As DWScript uses Generics, I needed a newer version of the Free Pascal compiler than what they provide on their home page (2.6).

Fortunately I had Laz4Android installed, which came with a build of FPC 2.7.1
This also provided me with the Masks unit that some DWScript units needed.
(I found mine in laz4android/components/lazutils)

I initially made some horrible hacks to the DWScript code to just get it compiling (deleting entire classes, casting wide to ansi strings, etc.), a simple proof-of-concept to see if it was worthwhile continuing.

Once I had a working DLL, I decided to update my version of Laz4Android to see if it fared any better at the Generics stuff...
Error: Undefined symbol: VMT_$DWSUTILS_$$_$GENDEF386

Hmm, Google had nothing on it, nothing on GENDEF386, couldn't find mention of this in the sources.
Oh well, no worry, I'll just try:
  • compiling FPC from SVN
  • CrossFPC
  • CodeTyphon
  • A random version of Laz4Android I found
  • Building it all on the command line using FPC, then linking it all manually with verbosity set to "I can show you the world"
...
Error: Undefined symbol: VMT_$DWSUTILS_$$_$GENDEF386
Well screw you too.

I've done some investigation into it, I built a little Python Pascal Parser to detect differentiating Interface/Implementation function descriptions and found some things... but nothing the compiler seems upset about.
So instead, if you want to use Free Pascal to compile this, you can try using the binary dump of FPC2.7.1 I took from my working version of Laz4Android from here.

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Because I suffer from rare diseases (like getting to know people in shops really well then not being able to go there anymore because I feel like I'm making them feel awkward), I ended up porting the smallpt global illumination renderer from 99 lines of C++ code to 666 lines of Turbo Pascal 3 code.

Doing this meant I got to play with loads of things:
  • Turbo Pascal 1, 3, 4, 5 and 7, Delphi...
  • Lazarus
  • FreePascal (for Android and iPhone and GBA)
  • Pascal Script and DWScript (hint: unless you've run out of paint to watch dry, you really want to use the DWScript version)
  • FreeDOS
  • Virtual Machines like Bochs, VirtualBox, DOSBox




See most of the gory blah-blah details here

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Being stupid is a wonderful thing: you discover new things every day.
I bought a Velleman USB Experiment board from Maplin as an exercise in learning how to solder.

One embarrassing turn led to another, and eventually I "discovered" that piezo buzzers generate current when you mash them.

That sparked the idea to use the piezo buzzers as a drum pad by converting the voltage into velocity sensitive MIDI notes.

Sadly, it had all been done before, many, many, many times.

But this is for all you Velleman owners out there.

See http://noshbar.xtreemhost.com or http://www.noshbar.co.cc if that ever works again.

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