icalendar devel - Jun 2010 - Windows line endings not handled correctly

Hi,

I''ve been using this library to re-encode some information from a 
3rd-party API, and Google Calendar was failing to parse the results. I 
believe I''ve tracked down the problem to the handling of line endings 
when setting properties.

Given the string "a\r\nb" as input, the output will be
"a\r\\nb" - the
CR is output literally, but the LF is escaped as ''\n''. An
interpreter
might consider the CR to be a newline, and the ''\n'' (since it
is not
indented) to be the next property in the file.

The correct action in this example would be to escape the entire CRLF 
sequence as a single ''\n'', or more generally to normalise all
line
endings before encoding.

It appears that VPIM has the same problem, but RiCal appears to handle 
this situation correctly.

Example:

require ''icalendar''
Icalendar::Calendar.new.tap{ |cal| cal.event do description "a\r\nb"
end
}.to_ical
# => 
"BEGIN:VCALENDAR\r\nCALSCALE:GREGORIAN\r\nPRODID:iCalendar-Ruby\r\nVERSION:2.0\r\nBEGIN:VEVENT\r\nDESCRIPTION:a\r\\nb\r\nDTSTAMP:20100620T011601\r\nSEQUENCE:0\r\nUID:2010-06-20T01:16:01+01:00_969670122
at Norman\r\nEND:VEVENT\r\nEND:VCALENDAR\r\n"

# should be
# => 
"BEGIN:VCALENDAR\r\nCALSCALE:GREGORIAN\r\nPRODID:iCalendar-Ruby\r\nVERSION:2.0\r\nBEGIN:VEVENT\r\nDESCRIPTION:a\\nb\r\nDTSTAMP:20100620T011601\r\nSEQUENCE:0\r\nUID:2010-06-20T01:16:01+01:00_969670122
at Norman\r\nEND:VEVENT\r\nEND:VCALENDAR\r\n"

Regards,
Rowan Collins

Hi,

Sorry to follow-up to my own post, but now it''s not so late at night, 
here''s a quick patch to fix the bug mentioned.

Regards,
Rowan Collins



On 20/06/10 01:50, Rowan Collins wrote:
> Hi,
>
> I''ve been using this library to re-encode some information from a 
> 3rd-party API, and Google Calendar was failing to parse the results. I 
> believe I''ve tracked down the problem to the handling of line
endings
> when setting properties.
>
> Given the string "a\r\nb" as input, the output will be
"a\r\\nb" - the
> CR is output literally, but the LF is escaped as ''\n''. An
interpreter
> might consider the CR to be a newline, and the ''\n''
(since it is not
> indented) to be the next property in the file.
>
> The correct action in this example would be to escape the entire CRLF 
> sequence as a single ''\n'', or more generally to normalise
all line
> endings before encoding.
>
> It appears that VPIM has the same problem, but RiCal appears to handle 
> this situation correctly.
>
> Example:
>
> require ''icalendar''
> Icalendar::Calendar.new.tap{ |cal| cal.event do description
"a\r\nb"
> end }.to_ical
> # => 
>
"BEGIN:VCALENDAR\r\nCALSCALE:GREGORIAN\r\nPRODID:iCalendar-Ruby\r\nVERSION:2.0\r\nBEGIN:VEVENT\r\nDESCRIPTION:a\r\\nb\r\nDTSTAMP:20100620T011601\r\nSEQUENCE:0\r\nUID:2010-06-20T01:16:01+01:00_969670122
at Norman\r\nEND:VEVENT\r\nEND:VCALENDAR\r\n"
>
>
> # should be
> # => 
>
"BEGIN:VCALENDAR\r\nCALSCALE:GREGORIAN\r\nPRODID:iCalendar-Ruby\r\nVERSION:2.0\r\nBEGIN:VEVENT\r\nDESCRIPTION:a\\nb\r\nDTSTAMP:20100620T011601\r\nSEQUENCE:0\r\nUID:2010-06-20T01:16:01+01:00_969670122
at Norman\r\nEND:VEVENT\r\nEND:VCALENDAR\r\n"
>
>
> Regards,
> Rowan Collins
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On 06/20/2010 09:55 AM, Rowan Collins wrote:
> Hi,
> 
> Sorry to follow-up to my own post, but now it''s not so late at
night,
> here''s a quick patch to fix the bug mentioned.
> 
> Regards,
> Rowan Collins
Thank you for the bug and the fix.  Patch applied and version 1.1.5 is
now released with your changes included.

	-Sean

-- 
__________________________________________________________________

Sean Dague                                       Mid-Hudson Valley
sean at dague dot net                            Linux Users Group
http://dague.net                                 http://mhvlug.org

There is no silver bullet.  Plus, werewolves make better neighbors
than zombies, and they tend to keep the vampire population down.
__________________________________________________________________


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