[Pidgin] #12617: Patch to add out-of-band DTMF support

[Pidgin]

#12617: Patch to add out-of-band DTMF support
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 Reporter:  BigBrownChunx                |        Owner:  darkrain42
     Type:  patch                        |       Status:  new       
Milestone:  Patches Needing Improvement  |    Component:  libpurple 
  Version:  2.7.3                        |   Resolution:            
 Keywords:  dtmf media                   |  
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Comment(by darkrain42):

 BigBrownChunx, another update after banging my head against hiptobecubic's
 backtraces in #pidgin:

 This code crashes when the media session is a !GoogleSession, not
 !JingleSession (i.e. in the expected use case of Google Voice).  Two
 changes needed:
    * Only send XEP-0181 DTMF if the other side advertises support for the
 feature (see the spec)
    * Have a jabber function (the one actually set for the prpl) which
 checks if this is a !JingleSession or !GoogleSession (or something that
 otherwise keeps `jingle_rtp_send_dtmf` from trying to dereference the
 wrong type of variable).

 Type safety in jingle_rtp_send_dtmf
 (`g_return_if_fail(JINGLE_IS_SESSION(...))` probably also good )

-- 
Ticket URL: <http://developer.pidgin.im/ticket/12617#comment:14>
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