Fix 328

[AntonioCohimbra]

Closes 328.

[felixdivo]

This doesn't really allow more than the two filters, right?

[christiansandberg]

As I interpreted the API docs, you can only set one filter per ID type, but I don't remember actually testing it.

[felixdivo]

Yes, that's how I got that as well. I was just confused by the commit message "allow more than one filter for vector". Ah, but now I get how the bugfix works!

[AntonioCohimbra]

From the vector doc I also understood, that only 1 filter per ID type is possible. Reading it again, it also could work with more than that... Anyway it is possible to pack multiple message IDs in one call of SetChannelAcceptance by combining them in the mask parameter:

	Binary	General rule
ID = 6 (0x006)	0110	-
ID = 4 (0x004)	0100	-
Mask	1101	Compare the Ids at each bit position. If they are different, mask at this bit position must be ‘0’.
Code	0110	Take one Id (it does not matter which one).

[felixdivo]

Ah right: We could write an interface independent helper function that combines the masks, each for the extended and normal type. Then, we could send that to the driver, and signal in _receive_internal() that filtering has not yet taken place. That way, we at least let the driver do some of the "heavy lifting".

Do you by chance have time for that that as well?