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This is an automatically generated e-mail. To reply, visit:
<a href="https://reviewboard.asterisk.org/r/4382/">https://reviewboard.asterisk.org/r/4382/</a>
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<p style="margin-top: 0;">On January 28th, 2015, 8:15 a.m. CST, <b>Matt Jordan</b> wrote:</p>
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<a href="https://reviewboard.asterisk.org/r/4382/diff/2/?file=71148#file71148line115" style="color: black; font-weight: bold; text-decoration: underline;">/branches/13/res/stasis/stasis_bridge.c</a>
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(Diff revision 2)
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "></pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "><span class="p">{</span></pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "><span class="tb"> </span><span class="k">if</span> <span class="p">(</span><span class="n">bridge_channel</span><span class="o">-></span><span class="n">swap</span><span class="p">)</span> <span class="p">{</span></pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "></pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "><span class="tb"> </span><span class="tb"> </span><span class="k">struct</span> <span class="n">stasis_app_control</span> <span class="o">*</span><span class="n">swap_control</span> <span class="o">=</span> <span class="n">stasis_app_control_find_by_channel</span><span class="p">(</span><span class="n">bridge_channel</span><span class="o">-></span><span class="n">swap</span><span class="p">);</span></pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "><span class="tb"> </span><span class="tb"> </span><span class="cm">/* copy the app name from the swap channel */</span></pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "><span class="tb"> </span><span class="tb"> </span><span class="k">if</span> <span class="p">(</span><span class="n">swap_control</span><span class="p">)</span> <span class="p">{</span></pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "></pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "><span class="tb"> </span><span class="tb"> </span><span class="tb"> </span><span class="n">ast_debug</span><span class="p">(</span><span class="mi">3</span><span class="p">,</span> <span class="s">"Copying stasis app name %s from %s to %s</span><span class="se">\n</span><span class="s">"</span><span class="p">,</span></pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "><span class="tb"> </span><span class="tb"> </span><span class="tb"> </span><span class="tb"> </span><span class="n">app_name</span><span class="p">(</span><span class="n">control_app</span><span class="p">(</span><span class="n">swap_control</span><span class="p">)),</span></pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "><span class="tb"> </span><span class="tb"> </span><span class="tb"> </span><span class="tb"> </span><span class="n">ast_channel_name</span><span class="p">(</span><span class="n">bridge_channel</span><span class="o">-></span><span class="n">swap</span><span class="p">),</span></pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "><span class="tb"> </span><span class="tb"> </span><span class="tb"> </span><span class="tb"> </span><span class="n">ast_channel_name</span><span class="p">(</span><span class="n">bridge_channel</span><span class="o">-></span><span class="n">chan</span><span class="p">));</span></pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "><span class="tb"> </span><span class="tb"> </span><span class="tb"> </span><span class="n">ast_channel_lock</span><span class="p">(</span><span class="n">bridge_channel</span><span class="o">-></span><span class="n">chan</span><span class="p">);</span></pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "><span class="tb"> </span><span class="tb"> </span><span class="tb"> </span><span class="n">app_set_replace_channel_app</span><span class="p">(</span><span class="n">bridge_channel</span><span class="o">-></span><span class="n">chan</span><span class="p">,</span> <span class="n">app_name</span><span class="p">(</span><span class="n">control_app</span><span class="p">(</span><span class="n">swap_control</span><span class="p">)));</span></pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "><span class="tb"> </span><span class="tb"> </span><span class="tb"> </span><span class="n">ast_channel_unlock</span><span class="p">(</span><span class="n">bridge_channel</span><span class="o">-></span><span class="n">chan</span><span class="p">);</span></pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "><span class="tb"> </span><span class="tb"> </span><span class="p">}</span></pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "><span class="tb"> </span><span class="tb"> </span><span class="n">ao2_cleanup</span><span class="p">(</span><span class="n">swap_control</span><span class="p">);</span></pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "><span class="tb"> </span><span class="p">}</span></pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "></pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "><span class="tb"> </span><span class="k">return</span> <span class="n">ast_bridge_base_v_table</span><span class="p">.</span><span class="n">push_peek</span><span class="p">(</span><span class="n">self</span><span class="p">,</span> <span class="n">bridge_channel</span><span class="p">,</span> <span class="n">swap</span><span class="p">);</span></pre></td>
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<td bgcolor="#c5ffc4" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "><span class="p">}</span></pre></td>
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<pre style="white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;">You may want to consider the usage of a goto here (gasp!) to reduce indentation:
if (!bridge_channel->swap) {
goto return_base_impl;
}
...
return_base_impl:
return ast_bridge_base_v_table.push_peek(self, bridge_channel, swap);</pre>
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<pre style="margin-left: 1em; white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;">I don't agree with the use of goto here just to reduce indentation. The indentation level savings are not much and the function is small.</pre>
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<p>- rmudgett</p>
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<p>On January 27th, 2015, 8:55 p.m. CST, Scott Griepentrog wrote:</p>
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<div>Review request for Asterisk Developers.</div>
<div>By Scott Griepentrog.</div>
<p style="color: grey;"><i>Updated Jan. 27, 2015, 8:55 p.m.</i></p>
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<b style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Bugs: </b>
<a href="https://issues.asterisk.org/jira/browse/ASTERISK-24649">ASTERISK-24649</a>
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<b style="color: #575012; font-size: 10pt;">Repository: </b>
Asterisk
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<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Description </h1>
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<pre style="margin: 0; padding: 0; white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;">During an attended transfer of a channel in stasis, where a local channel is used to replace (swap in for) a PJSIP channel, there is a race condition. The PJSIP REFER transfer has been initiated (ast_bridge_impart) but will be completed later on another thread (bridge_channel_ind_thread), however, prior to the stasis bridging callback (bridge_stasis_push) being called the PJSIP channel is hungup, which allows the stasis app loop to exit, deleting the stasis control. That prevents the stasis bridge callback from getting the app name from the channel being replaced (swap).
This patch adds a new stasis bridge callback push_peek, which is called from the ast_bridge_impart() thread. This allows the new bridge_stasis_push_peek() function to copy the stasis app name from the originating channel before the PJSIP channel can be hungup.</pre>
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<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Testing </h1>
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<pre style="margin: 0; padding: 0; white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;">Running tests/rest_api/external_interaction/attended_transfer/stasis_bridge_to_stasis_app now does not result in an occasional failure.</pre>
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<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Diffs</b> </h1>
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<li>/branches/13/res/stasis/stasis_bridge.c <span style="color: grey">(431242)</span></li>
<li>/branches/13/main/bridge_channel.c <span style="color: grey">(431242)</span></li>
<li>/branches/13/main/bridge.c <span style="color: grey">(431242)</span></li>
<li>/branches/13/include/asterisk/bridge.h <span style="color: grey">(431242)</span></li>
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<p><a href="https://reviewboard.asterisk.org/r/4382/diff/" style="margin-left: 3em;">View Diff</a></p>
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