xdg-open can't handle URI schemes containing numbers

Submitted by Elliot Kendall

Assigned to Portland Bugs

Link to original bug (#104973)

Description

Per RFC 3986, 'Scheme names consist of a sequence of characters beginning with a letter and followed by any combination of letters, digits, plus ("+"), period ("."), or hyphen ("-").' However, the is_file_url_or_path() function in xdg-open relies on the following regular expression to identify valid URI schemes:

^[[:alpha:]+.-]+:

Not only does that fail on URI schemes that contain numbers (such as h323, irc6, pkcs11, tn3270, etc.) it also incorrectly identifies strings beginning with + . or - as valid URIs.

I propose the following replacement:

^[:alpha:][[:alnum:]+.-]*:

This bug is present in the most recent version of xdg-open in git.