[asterisk-bugs] [Asterisk 0018585]: [patch] AMI redirect from meetme - calls fail

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=18585 
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Reported By:                oej
Assigned To:                
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Project:                    Asterisk
Issue ID:                   18585
Category:                   Channels/General
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     confirmed
Asterisk Version:           SVN 
JIRA:                       SWP-2893 
Regression:                 No 
Reviewboard Link:            
SVN Branch (only for SVN checkouts, not tarball releases):  1.4  
SVN Revision (number only!): 300917 
Request Review:              
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Date Submitted:             2011-01-07 08:48 CST
Last Modified:              2011-01-24 14:32 CST
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Summary:                    [patch] AMI redirect from meetme - calls fail
Description: 
Possibly related to bug https://issues.asterisk.org/view.php?id=18230 and review
https://reviewboard.asterisk.org/r/1013/

Two calls in a meetme.
Issue a redirect to get one call out to the dialplan - play a prompt
there.

The call hangs up with no prompt played. The PBX jumps to the dialplan and
executes entries, but playback and wait fails

If you have a normal call and a normal PBX bridge, it works.

Testing with Asterisk 1.4 rev 300917

This has been working in earlier releases. I strongly suspect the changes
in the above commits to have changed something.
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Relationships       ID      Summary
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related to          0018230 [regression] Redirect function (over co...
has duplicate       0018612 Redirect channels FROM Meetme causes ha...
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 (0130950) svnbot (reporter) - 2011-01-24 14:32
 https://issues.asterisk.org/view.php?id=18585#c130950 
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Repository: asterisk
Revision: 303546

U   branches/1.4/apps/app_meetme.c
U   branches/1.4/include/asterisk/channel.h
U   branches/1.4/main/channel.c
U   branches/1.4/main/pbx.c
U   branches/1.4/res/res_features.c

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r303546 | russell | 2011-01-24 14:32:23 -0600 (Mon, 24 Jan 2011) | 31
lines

Fix channel redirect out of MeetMe() and other issues with channel
softhangup.

Mantis issue https://issues.asterisk.org/view.php?id=18585 reports that a
channel redirect out of MeetMe()
stopped
working properly.  This issue includes a patch that resolves the issue by
removing a call to ast_check_hangup() from app_meetme.c.  I left that in
my
patch, as it doesn't need to be there.  However, the rest of the patch
fixes
this problem with or without the change to app_meetme.

The key difference between what happens before and after this patch is the
effect of the END_OF_Q control frame.  After END_OF_Q is hit in
ast_read(),
ast_read() will return NULL.  With the ast_check_hangup() removed,
app_meetme
sees this which causes it to exit as intended.  Checking
ast_check_hangup()
caused app_meetme to exit earlier in the process, and the target of the
redirect saw the condition where ast_read() returned NULL.

Removing ast_check_hangup() works around the issue in app_meetme, but
doesn't
solve the issue if another application did the same thing.  There are also
other edge cases where if an application finishes at the same time that a
redirect happens, the target of the redirect will think that the channel
hung
up.  So, I made some changes in pbx.c to resolve it at a deeper level. 
There
are already places that unset the SOFTHANGUP_ASYNCGOTO flag in an attempt
to
abort the hangup process.  My patch extends this to remove the END_OF_Q
frame
from the channel's read queue, making the "abort hangup" more complete. 
This
same technique was used in every place where a softhangup flag was
cleared.

(closes issue https://issues.asterisk.org/view.php?id=18585)
Reported by: oej
Tested by: oej, wedhorn, russell

Review: https://reviewboard.asterisk.org/r/1082/

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http://svn.digium.com/view/asterisk?view=rev&revision=303546 

Issue History 
Date Modified    Username       Field                    Change               
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2011-01-24 14:32 svnbot         Checkin                                      
2011-01-24 14:32 svnbot         Note Added: 0130950                          
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