mirror of
https://github.com/danbulant/Cosmos
synced 2026-05-20 12:58:39 +00:00
93 lines
4.8 KiB
HTML
93 lines
4.8 KiB
HTML
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
|
|
|
|
<html xmlns="http://www.w3.org/1999/xhtml">
|
|
<head>
|
|
<title></title>
|
|
</head>
|
|
<body>
|
|
|
|
<p>
|
|
Plugs are used to fill "holes" in .NET libraries and replace them with different
|
|
code. Holes exist for example when a method in .NET library uses a Windows API
|
|
call. That API call will not be available on Cosmos. One method would be to
|
|
emulate the Windows API as WINE does, but the API is a low level C style API
|
|
relying on memory structures. Emulating it would be highly inefficient. Instead,
|
|
Cosmos replaces specific methods and property implementations that rely on
|
|
Windows API calls. Plugs can also be used to provide an alternate implementation
|
|
for a method, even if it does not rely on the Windows API.</p>
|
|
<p>
|
|
Plugs can be implemented in the following manners:</p>
|
|
<ul>
|
|
<li>Code Plug - Standard C# (or any .NET language) is used to provide the alternate
|
|
implementation.</li>
|
|
<li>Assembly Languge - In a few low level cases assembly language is used. This is
|
|
reserved for a few few cases and only allowed in the Cosmos.Core ring.</li>
|
|
</ul>
|
|
<p>
|
|
When a Cosmos project is compiled, IL2CPU creates a list of plugs. When it
|
|
encounters a method or property for which a plug exists, instead of using the IL
|
|
contained in the existing implementation, it substitutes the plug version
|
|
instead.</p>
|
|
<h3>
|
|
Plug Targets</h3>
|
|
<ul>
|
|
<li>Source Plugs - Used to target a class library without modifiable or available
|
|
source.
|
|
For example the Console class in the .NET Framework. The Console class uses the
|
|
Windows API, so plugs can be used to redefine the methods in the Console class
|
|
to use code which interacts with Cosmos instead. For these types of plug
|
|
targets, the attributes are specified on the plug implemenation since the source
|
|
cannot be modified of the target. If we coud modify the source, we wouldn't need
|
|
plugs. :)Sou</li>
|
|
<li>Assembly Plug - Empty methods which create a sort of "abstract" class are used
|
|
to define an interface to an assembly language plug. This type of plug is rare
|
|
and only for the core ring. For these types of plugs, the attributes are
|
|
specified on the target, rather than the implementation.</li>
|
|
</ul>
|
|
<p>
|
|
Non source targets should never need to use assembly language, but if they do
|
|
the plugs must be cascaded since assembly language plugs can only be applied to
|
|
classes with modifiable source.</p>
|
|
<h3>
|
|
Implementing a Plug</h3>
|
|
<p>
|
|
Plugs can be applied at the class, or to an individual method or property. Plug
|
|
implementations are defined by applying attributes to the class which provides
|
|
the plug implementation.</p>
|
|
<h3>
|
|
Plug Assembly Naming in Cosmos</h3>
|
|
<p>
|
|
Plugs assemblies in Cosmos are named in the following manner.</p>
|
|
<p>
|
|
Cosmos.<ring>.Plugs.<Unique section of target namespace></p>
|
|
<p>
|
|
ie Cosmos.System.Plugs.System</p>
|
|
<p>
|
|
Normally only one section will exist after plugs, but mutliple sections could
|
|
exist to further seperate a group of plugs into multiple assemblies. In the
|
|
previous example we can determine the following information:</p>
|
|
<ul>
|
|
<li><b>Cosmos</b>.System.Plugs.System - All Cosmos assemblies start with Cosmos.*.
|
|
User assemblies should not use the Cosmos. prefix.</li>
|
|
<li>Cosmos.<b>System</b>.Plugs.System - The plugs are part of the System ring.</li>
|
|
<li>Cosmos.System.<b>Plugs</b>.System - Plugs seperates plugs from normal code with
|
|
in the Cosmos.System.*</li>
|
|
<li>Cosmos.System.Plugs.<b>System</b> - The plugs in this assembly will apply to
|
|
System.*. It could also be System.Collections for example to apply to
|
|
System.Collections.*</li>
|
|
</ul>
|
|
<p>
|
|
Plugs should be implemented in the highest ring possible and according to the
|
|
code in the plug, not according to the class to which the plug targets. Most
|
|
plugs should be in fact in the system ring. Except for a few special plugs
|
|
needed by the compiler, off hand I cannot think of any that should be
|
|
implemented in any ring lower than the system ring.</p>
|
|
|
|
<p>
|
|
<b>Plug Target</b></p>
|
|
<p>
|
|
Please specify the PlugTarget using the fully qualified name, like:
|
|
global::System.Console. To avoid later name colisions.</p>
|
|
|
|
</body>
|
|
</html>
|