The format of Shared MIME Database magic values

[Jerome Leclanche]

There is a Qt 4 port of this.

As for windows support... I've been down that road, trying to provide
it. Windows' feature set doesn't even sort of come close; it only
provides real mime types for a limited set of registered extensions,
and it doesn't provide any of the very useful features such as
subclassing, etc. In the end, I gave up and am only providing
xdg-based mime types. I think Qt made an excellent choice in providing
the xdg database itself. But if you choose against that, good luck.

Anyway you can have a look at my python-based mimetype lib. Magic
matches are implemented on line 192 onwards.

https://github.com/Adys/python-xdg/blob/master/xdg/mime.py

J. Leclanche


On Fri, Dec 13, 2013 at 7:56 PM, Alexander Kamyshnikov
<axill777 at gmail.com> wrote:
> Yes, i had. But i decided to write my own implementation because:
> a) my project is forced to use Qt4 only (clients have very old versions of
> modified Red Hat with XDG_DATA_DIRS undefined);
> b) Windows support (through reading registry HKCR/.ext keys) is required;
> c) I'm very curious :)
>
> You think i'm should look deeply at the qmimedatabase.cpp however?
>
>
> 2013/12/13 Jerome Leclanche <adys.wh at gmail.com>
>>
>> Have you had a look at the Qt 5 mimetype module?
>>
>> http://qt-project.org/doc/qt-5.0/qtcore/qmimedatabase.html
>> J. Leclanche
>>
>>
>> On Fri, Dec 13, 2013 at 7:35 PM, Alexander Kamyshnikov
>> <axill777 at gmail.com> wrote:
>> > Hi all!
>> > I'm developing the implementation of MIME database in C++/Qt for one
>> > commercial program (requirement managment tool, if one will be
>> > interested).
>> > So my question is: the format of magic values to compare file header
>> > data
>> > with is not specified exactly in the spec. I mean the magic/match/value
>> > attribute.
>> > What exactly mean those magic strings from
>> > /usr/share/mime/packages/freedesktop.org.xml from my Kubuntu?
>> > 1) "\1\9"
>> > 2) "\376\067\0\043"
>> > 3) "\x8AMNG\x0D\x0A\x1A\x0A"
>> > Second is looks like octal number in C notation, third - hexadecimal,
>> > but
>> > about first i'm not sure. It is just "usual" decimal value?
>> > What format exactly should use magic values?
>> > Thanks for your help. WBR, Alexander
>> >
>> > P.S. Spec i'm using living here:
>> >
>> > http://standards.freedesktop.org/shared-mime-info-spec/shared-mime-info-spec-latest.html#id2661973
>> > P.S. <match> items can be nested. But i can't find yet the clear way to
>> > implement their storage programmatically. Some kind of tree, or reverse
>> > polish notation should be used here? nevermind
>> >
>> > _______________________________________________
>> > xdg mailing list
>> > xdg at lists.freedesktop.org
>> > http://lists.freedesktop.org/mailman/listinfo/xdg
>> >
>
>