Jul
25

Donation Page 2017

While I was fixing up an application that I hadn't worked on in a while, I noticed that it linked to a donation page on the previous blog. A donation page that no longer existed when I revamped things; I've just been sorting that out.

There's now a dedicated donate page and a link to it at the top of this very page.

I'm honestly not really expecting much from it as my software was donation-ware for almost 20 years and, well, it didn't exactly go very well. This forced me to finally start writing commercial software and stop giving it away for free. Well, there are "free editions" available so they can still be used for free if you don't require the more advanced features (and aren't particularly bothered about supporting the software). I couldn't bring myself to put the software entirely behind a paywall.

Shame, really.

(Incidentally, this is why there isn't a "next generation" of Comica as I can't really charge for it and I can no longer give away software for free)

Jul
24

Assembler, part 5 2017

In the previous version, Assembler parsed down the entered code into Instructions which contained an enum for denoting the type of that instruction. For example, Move being set as the property would mean it was a Move instruction.

Now that property has been removed and all Instructions inherit from BaseMnemonic (and some other interface). So, the Move instruction is now its own Move class.

All mnemonics for a CPU are defined within a Mnemonics collection when a Machine is instantiated (along with registers and such within the CPU class); there's (currently) a method that allows the mapping of a textual mnemonic to its class counterpart during the parsing stage; this may later be changed to a Dictionary or something.

Some limited parsing is in for determining what the source and destination operands consist of. This is the most complex part as those operands can contain everything from a plain immediate value to relative addressing.

Because of this, each instruction will have to maintain metadata on exactly what's going on within that instruction; having to parse more than once to later on to determine what needs to happen is silly, so lots of metadata is required. As a bonus, we'll get a ton of helpful debugging info for "free" when we implement all that gubbins.

On the interface side of things (c'mon, like I can resist UI work) the syntax highlighting now colourises the datatype (or size as is the actual term) for mnemonics. Turned out this was achievable via making the datatypes an operator when it comes to highlighting as they don't need to be on word boundaries - thanks to Rob for the suggestion. Still more highlighting work required.

The Registers window now has a trace of what it parsed from the entered source code and displays the interpreted code. Changed the font to a mono-space one as the other just looked messy when registers' widths didn't line up. Sorry Segoe UI - not this time.

Editor and Registers

Jul
22

Assembler, part 4 2017

What am I doing?

I've once again resumed working on the interface rather than the actual core; I still don't even know if any of this truly works. Sheesh.

Not a whole lot to report from yesterday as I practically spent the day reading while doing the odd bit of UI tinkering. Big thanks to Rob for reminding me about SyntaxBox! Scintilla is pretty horrible overall and SB is done so much better, so I'm glad the editor is now more solid. Code folding was extremely easy to implement, unlike Scintilla where I just couldn't be bothered and worked on another part instead.

Today I started a new control for displaying parsed instructions. Think of it as a ListBox but with no user interaction, and the "current item" is always vertically centred and highlighted; currently adding column support to tabulate the view. Oh, issue: I can't get the background transparent no-matter what. I've done millions of transparent controls in the past, so this is confusing the hell out of me.

Next, I need to have a go at actually executing instructions. I've done very little bit-work in .NET so I'm not sure how that's going to go, especially as I don't even know the syntax for VB.Net; presumably it's going to be bat-shit insane compared to C#.

Nothing instead of just null still annoys me to this very day.

Jul
20

Assembler, Part 3 2017

I've gone ahead and added the BaseMnemonic class, along with a IMnemonic interface that all CPU mnemonics (instructions, op-codes - whatever you want to call them) inherit from.

The past hour or so has been spent improving the interface and adding things where necessary. The main window now features has the standard set of root menu items (File, Edit, View, Debug, Tools, Help) and there's a (currently collapsed) project viewer.

Added a Messages window that will show To-do items, syntax errors, and the like. Also added Status Register to the Registers window. The tooltip for each register's value also displays the value of that register's contents in base 10 (Decimal) and likely base 16 (Hex) in the near future, too.

Next up is making use of the BaseMnemonic class by implementing the Move instruction. Oooh!

Messages and Registers windows


Assembler, Part 2

Part number the two!

Did some more work on the Assembler project (part 1 here) that didn't just involve improving the interface. Ooh, ooh - what?

Parsing. That's what.

Hitting Run (or F5) now results in the entered code being parsed and added to an Instructions collection. The following style is correctly parsed:

<mnemonic><datatype> <source_operand>, <dest_operand>

An example of which is:

move.l #4, d0 ; an optional comment which isn't explicitly captured

mnemonic is the instruction (move, add, etc). datatype is the size which is either .b (byte), .w (word), .l (long-word). source_operand and dest_operand is where stuff happens (values, registers, addresses, and the like).

Each line in the source is read one-by-one. Once a line is read, a regular expression1 match is attempted (hard-coded add and move for now) .

(add|move)(?:\.(l|b|w)?)? *(.*), (\w*)

Note that this expression is far from complete. First change would involve removing the rigid white-space structure.

The reason for the datatype being optional in the regex is because I thought it could be omitted from assembler source. Doing a bit of research seems to show that everyone always includes a datatype (or size as I think is the nomenclature), so I've dropped the idea of having a default type. Still, this now means I can detect and specifically give an error about any missing types.

Anyway, back to parsing.

If the line fails the regex match, then onto the next line. If it succeeds, the parsing continues and an Instruction object is created containing mnemonic and datatype. I haven't yet figured out how the source and destination operands are going to be represented. In assembler code, they can be addresses, registers, or whatever else so I don't really know what's going to happen until I just start typing.

Undecided if mnemonics should inherit from a baseMnemonic and be individual classes, or if I should continue with the mnemonic simply being an enum on Instruction. I like instructions being self-contained, but comparisons become more involved. I'm leaning more towards baseMnemonic with a defined Interface so instructions can do whatever the hell they want as long as they take in an input and give back an output.

Thinking further ahead, I'm also undecided if the entire assembler source should be parsed in one go or instead proceed one line at at time. The latter will allow code to be edited while the program is running, which is quite nice, and goes hand-in-hand with the Step debugger feature.

Right now, I can't think of any advantages of parsing in one go (parse each line and populate Instructions immediately before execution even starts). Maybe "compiler" optimisations at a later date? Performance isn't even a minor consideration, so I don't see that as much of a win. I think the step-by-step method simply gives more advantages and so that may very well be the route to take.

1 I can highly recommend Regex Pal for writing and testing expressions.

Jul
19

Assembler, Part 1 2017

I don't yet have a name for the Assembler language program-thingy I'm doing so I'm just going to refer to it as Assembler (giev suggestions!) for the time being. Cool? Cool.

As mentioned in a previous post, I'm taking time out from my commercial software and am instead working on fun little projects. Clearly, our definition of the word fun differs greatly.

I wrote a Turing program a long time ago and recently it occurred to me that I could get a more advanced version by essentially emulating a CPU. The Turing machine is pretty much what that is. In this case, I'd be going with a Motorola 68000. Because it's lovely, and because it seems simple enough as compared to the nightmares that are the x86 and x68 architectures. Bear in mind that I don't really know much about assembler/assembler other than tinkerings back in the late 1990s.

Most of the time so far has been spent creating a lexer (syntax highlighter) for Scintilla. Being a .NET OOP guy and working with Scintilla.NET (which doesn't attempt to really refactor anything), its API is a complete mess. So it took me quite a while to get highlighting happening, and it's still not done. Thankfully there's a project called ScintillaNET-Kitchen that helps out.

I haven't gone for a multi-document interface or anything that you'd find in more complete IDEs - how do I even know if this project will work satisfactorily? Hell, saying that, I've (partly!) made it possible to switch in new CPUs. I think that itself is a bit much and so don't currently plan on fully adding support for such a feature. Hmm... I could also create a chipset with multiple chips...? No - NO. Stop right there.

Yeah, alright - what the eff is the point?

Fun. As said above.

I'm going to keep adding to it. Forever. CPUs don't tend to do a whole lot on their own; their instruction sets aren't very big, either. Lots of shunting of data all over the place. Of course this is simplified and from someone that doesn't really assembler-me-do, but how hard can it be?

So, if I can get the basics working then I can start adding built-in routines that a program can call to do more advanced stuff. A video display would need to be added, of some sort. Only being able to manipulate registers isn't the most exciting thing after the initial novelty wears off.

Shut up and tell me if it's done yet

Hell no it isn't done. It doesn't even parse the entered code yet. There's the editor with all its syntax highlighting tomfoolery, and there's the Registers window that displays the contents of each register. That bit works; it shows exactly what's in the registers, but they can't be set using code yet.

There's a screenshot below. That's all there currently is. Will still if I have time to get the parsing - at least started - in today.

Assembler, screenshot uno

Edit: Did the opposite of what I said and have continued working on the interface. Oops.

Jul
17

A Week's Break 2017

The drawback of having a Category - Sub-category format is that you end up with silly stuff like the above.

Alright, I've just decided that I'm going to use the next week or so to work on fun little projects. Fun being an entirely subjective word, here.

I won't do anything on FileSieve, or Wake On LAN Ex, or anything of the sort. What I am going to work on, though, is... uh, I dunno - something?

One thing I thought of is y'know those Turing machines? The thing with the limited instruction set involving a pointer where you can program it to move to different cells and increment values, etc? No?

Well, one of those. I remember making one in the morning after skipping college (I was young and an idiot, as opposed to now where I'm just old and an idiot) and I found it weirdly enjoyable.

I'd like to do an advanced version that uses instructions. Like, my own assembly language, ya dig? The language and parsing, etc, can be easily fudged with regular expressions, and the main core can be done with a state machine.

I only used assembly back in the Amiga days in very limited ways, such as counting the number of carriage returns in a text file to determine how many pages a document has. (this is referencing The Word, #amigarulezok)

This Turing++ project will give me a better grasp of how the hell people can write full programs in such a language. Squillions upon squillions of lines of code for even the most basic of things - how do you keep track of it all?


New Sections on BootBlock.co.uk

When I moved this blog thing over from the sub-domain, I kinda forgot that the main site had various links on it to different places such as the forums, my software, and of course to contact me.

Had a bit of a WTF moment the other day as I realised all of the said links were gone! No-one could view anything other than the absolute crud that I dribble onto here; it was only supposed to be a sub-domain and not the actual, main site.

Well. That changed.

I've now added a few sections at the top-right of this page; the main ones are links to my free and commercial software, and an area that contains contact information.

And I've just realised that this site doesn't say who I actually am.

Jul
16

FileSieve 4.20, Scripting, and Threads 2017

That's a new version of FileSieve done and released. I think this particular version has the biggest change log so far. It would've been bigger - he said - but I, for some reason, decided to revisit the Script plugin.

I don't think I've gone into this before other than with a small forum post, but I started a new (Method) plugin a while ago that is what amounts to a small programming environment.

The purpose of the Script plugin is to allow the user to program their own Method and Modifier plugins. Full intellisense, code completion, debugging, and all that guff. It's undoubtedly far too much effort for the outcome of only a few people even being able to effectively use it as it requires programming knowledge. And then the documentation. Holy crap - no, I've already been through that nightmare with the original VoiceMate Professional.

While working on the prescanning threads feature, for no explicable reason I decided to jump into the Script plugin and work on that. The plugin all now builds and runs, but then common sense won out in the end and I unloaded the project from the solution and ended it there.

As for the prescan threading: it didn't make it into 4.20. The scanning was never designed from the beginning with concurrency and so random things aren't thread-safe, resulting in Weird Things Happening. I'm not going to delay the new big release because of this, so the threading features were disabled and the new release has been made.

Jul
15

Pre-scanning Threads 2017

Just a quick one today as I'm feeling like sheeeeeet.

FileSieve 4.20 is shaping up to be a pretty hefty release as it contains the most changes for the 4 series to date. Because of that, I'm adding more changes, and even more changes. Gonna break a record? Do it properly.

Today's (partial, as I was away for a lot of the day) task is to try and get the Prescanning split into multiple threads.

Before FileSieve does its sieving thing, it has a Prescan stage where it gathers information on all of the files to be processed. This is currently a sequential process and can take a while as it needs to traverse the file system and grab various pieces of metadata.

Now, what if the files reside on different drives? We can portion out all Source Items (a directory, essentially) onto different threads depending on which drive they reside on. This needs a bit more than simply creating a list of Source Items per drive letter due to logical and physical drives. That is, a single drive may have multiple logical partitions, and we don't want to thrash the disk because we're too dumb to realise all of those partitions share the same drive heads.

This Prescan threading feature has been sat dormant in FileSieve for quite a while as I didn't get around to implementing the are-drive-letters-on-the-same-drive logic. Over the next couple of days I'm going to see if I can determine how feasible this is; I definitely do not want to rely on Windows Management Instrumentation as the WMI infrastructure is one bloaty mutha - it takes literal seconds to instantiate for the first time.