[Icecast-dev] How do you escape characters within the metadata block

["Thomas B. Rücker"]

On 07/06/2014 06:43 AM, John Selbie wrote:
> When "Icy-MetaData: 1" is in the HTTP request to the server, that
> indicates that the client wants to receive meta data inlined with the
> mp3 data stream.  The metadata interval is reported by the server via
> the "icy-metaint" header in the response stream.
>
> Such data looks like the following within the mp3 stream
>
>     StreamTitle='Ozzy Osbourne - Crazy
> Train';StreamUrl='http://myserver.org';
>
> Essentially a series of name/value pairs formatted with single-tick
> quotes around each value and delimited with Equals and Semicolon chars.
>
> Here is the question.  If the song title itself contains a quote char
> in it:
>
>     StreamTitle='Destiny's Child - Emotion';
>
> How is the tick mark within that stream title expected to be escaped
> such that the StreamTitle isn't parsed as just "Destiny" ?
>
> Is it a URL Encoding  (StreamTitle='Destiny%27s Child - Emotion';) ?
>
> A C style Encoding (StreamTitle='Destiny\'s Child - Emotion';) ?
>
> Or something else?
>
> I didn't see any escape code in the icecast server sources.  But I did
> see URL encodings for metadata in the libshout broadcast client
> sources.  So I suspect that's the answer. But I wasn't sure if the
> server did any re-encoding on the strings.
>
> Can someone confirm?

That's legacy-metadata, modelled after Shoutcast. So you'd need to look
how they do it and how players then expect it.
It is possible that there is a genuine bug in Icecast for not escaping
this, but the core team has no time to spend on legacy support. So if
someone wants to see this fixed, send a patch please, together with some
explanation how it follows general practice (there is no standard).

Cheers

Thomas
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.xiph.org/pipermail/icecast-dev/attachments/20140710/fbef370a/attachment.htm