XPCOM_README

In order to build the XPCOM component, download:

http://releases.mozilla.org/pub/mozilla.org/xulrunner/releases/1.8.0.4/sdk/gecko-sdk-win32-msvc-1.8.0.4.zip

Unzip into a dir named gecko-sdk in the same dir as the folder holding your clone of the repo.

Next download http://ftp.mozilla.org/pub/mozilla.org/mozilla/source/wintools.zip
In this zip find glib-1.2.dll and libIDL-0.6.dll, put them in gecko-sdk/bin

So your directory structure should look like:
projectroot/
	|
	-gecko-sdk/
	| -bin/
	| | _ ...
	|	| -glib-1.2.dll
	| | -libIDL-0.6.dll
	| |
	| +idl/
	| +include/
	| +lib/
	|
	-medivault/
		+.git/
		| ...
		-wrapper/
			+src/
			+xpcom/
			+docs/

Then the Visual Studio project in projectroot/medivault/wrapper/xpcom should build you a working component.

Refer to http://wanderingstan.com/2007-11-16/geekout_how_to_make_a_c_xpcom_component/ for more information (and some excellent links) on setting up XPCOM build environment for Visual Studio.