Improper treatment of percent escaped characters by gstsouphttpsrc

[Mateusz Kowalczyk]

Greetings,

I'm a Clementine (Qt based music player, a fork of Amarok) user which 
uses GStreamer as it's engine.

Today a user file a bug report about his .xpfs file not being properly 
played. In it, he has a URL pointed at some location on the Internet. 
The issue occurs when the URL has percent-escaped characters. In this 
case they happen to be ‘%5B’ and ‘%5D’ which stand for ‘[’ and ‘]’ 
respectively.


Now, there are some things I'd like to establish.

1. Clementine (or rather GStreamer) handles streams just fine.
2. The user interface and the whole back-end IS parsing the .xpfs fine, 
extracting the string as expected.
3. The string being passed to a GStreamer pipeline is still the same 
string, before the audio starts playing and after it stops.


Here's a small Clementine debug output. It contains a few more messages 
than it usually does as I spent quite a few hours ensuring that 
Clementine actually handles the URL properly and passes it to GStreamer 
as expected.

Url at start of Load "http://www.notarealurl.net/insub/%5Binsub05%5DJacques_Demierre-1-black_white_memories.mp3"
Url after Engine::Base::Load "http://www.notarealurl.net/insub/%5Binsub05%5DJacques_Demierre-1-black_white_memories.mp3"
gst_url  QUrl( "http://www.notarealurl.net/insub/%5Binsub05%5DJacques_Demierre-1-black_white_memories.mp3" )
About to create a pipeline from gst_url
Creating pipeline in GstEngine using CreatePipeline(url, nanosec)
url is  QUrl( "http://www.notarealurl.net/insub/%5Binsub05%5DJacques_Demierre-1-black_white_memories.mp3" )
Calling InitFromUrl with url:  QUrl( "http://www.notarealurl.net/insub/%5Binsub05%5DJacques_Demierre-1-black_white_memories.mp3" )
Managed to make a pipeline
Before BufferingFinished()
After BufferingFinished()
Done with pipeline creation; return true;
In Play
Setting QFuture
Leaving Play
position 0 scrobble point 31 status 0
1 "gstsouphttpsrc.c(1117): gst_soup_http_src_parse_status (): /GstPipeline:pipeline/GstURIDecodeBin:uridecodebin-0/GstSoupHTTPSrc:source:
Not Found (404), URL: http://www.notarealurl.net/insub/%255Binsub05%255DJacques_Demierre-1-black_white_memories.mp3"
Gstreamer error: "Not Found"
QTimeLine::start: already running
Stopping; old url_ is  QUrl( "http://www.notarealurl.net/insub/%5Binsub05%5DJacques_Demierre-1-black_white_memories.mp3" )

As can be seen above, I make sure a couple of times that the URL I have 
is correct. Once GStreamer tries to reach it however, it reports a 404 
error with a mangled URL (number 25 seems to be inserted for some 
reason; I haven't tried with other escape codes).

Is there something fundamental I'm missing? Is that plug-in not supposed 
to be able to handle such URLs?
I tried looking for the source of the mentioned file to check if it's 
doing anything funky, but the GStreamer repos were quite difficult to 
navigate.

I thought that I should ask on a mailing list before filing a bug report 
as there really might be something simple I fail to notice as I'm not 
familiar with GStreamer. If someone is able to stream such a URL, might 
have to go back and spend more time on the Clementine side of things, 
although I'm pretty confident that it's not the culprit here.


Thank you.