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<p class="MsoNormal">We are working on a patch for the REFER support and have a question on whether a lock is needed or not.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">In chan_pjsip.c function xfer_client_on_evsub_state, code is processing the REFER-NOTIFY subscription.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">It gets an ast_sip_session reference, then it acquires a ast_channel reference.<o:p></o:p></p>
<p class="MsoNormal">Should we make the code bump the lock count for the session’s channel while we use it? Unlocking when done using it?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Is it safe to assume the channel will not be deleted while this routine is running?<o:p></o:p></p>
<p class="MsoNormal">Obviously, the safest approach is to increment/decrement the reference count while using, but is that the necessary/preferred approach?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">chan = ao2_bump(session->channel);<o:p></o:p></p>
<p class="MsoNormal"><<use chan>><o:p></o:p></p>
<p class="MsoNormal">ao2_cleanup(chan);<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Dan<o:p></o:p></p>
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