Re: ANN: Ada Resource Embedder for C, Ada and Go

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

On 2021-06-11 19:32, Stephane Carrez wrote:

> Le vendredi 11 juin 2021 à 18:19:18 UTC+2, Dmitry A. Kazakov a écrit :
>> On 2021-06-11 15:51, Stéphane Rivière wrote:
>>> Hi Stephane,
>>>
>>>> I created a new tool to allow embedding any file in an Ada, C or Go binary.
>>>
>>> This is typically what I needed to improve my current AIDE v2 project
>>> (Ada Instant Development Environment - source GNAT CE 2019 2020 2021 -
>>> target Debian / Ubuntu with subtarget station (with GNATStudio, HAC,
>>> libs, debug aware RTS, and goodies) or server (bare minimal).
>> I considered embedding into relocatable libraries similar to Windows'
>> resource, e.g. for versioning plugins etc, but then decided to use an
>> easier and more universal method.
>>
>> I simply put an Ada constructing function into the library. The function
>> is exported. The address returned by GetProcAddress or dlsym goes to
>> Unchecked_Conversion to an access to subprogram, and here you are.
>>
>> The obvious advantage of this method over embedding is that the object
>> can be tagged of any derived type, which no embedding can do. And you
>> can add whatever further initialization or checks you might need.
> 
> Can you elaborate a little?
> I don't see what you put in your Ada constructing function.
> I do see how you use it but not how and where you put the original content or file.

In my case I do not deal with files, it is always objects. In the 
simplest case it could be a record type like:

    type Library_Data is record
       Do_This  : not null access procedure;
       Get_That : not null access function return That'Class;
    end record;

That the library provides.

> Let's suppose you have some documentation file 'config/example.conf'.

The documentation would be an object ready for rendering. Say the 
documentation renderer is GTK text view widget. Then that would require 
a text buffer:

    type Library_Data is record
       Do_This       : not null access procedure;
       Get_That      : not null access function return That'Class;
       Documentation : not null Gtk_Text_Buffer;
    end record;

The caller will drop the text buffer Documentation into a Gtk_Text_View 
widget to show the documentation.

I usually use programmatically generated content. E.g. HTML 
documentation would be a set of subprograms with parameters that put a 
portion of HTML into a stream/string. I then decorate their output as 
necessary, e.g. <tr>...</tr> if that must be a table cell etc.

The point that documentation is almost never a static text, but has all 
sorts of parameters the provider of does not know in advance.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de