[asterisk-bugs] [DAHDI-linux 0016165]: Native bridging from a span that isn't the master span can cause data corruption.

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=16165 
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Reported By:                sruffell
Assigned To:                sruffell
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Project:                    DAHDI-linux
Issue ID:                   16165
Category:                   General
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     assigned
JIRA:                        
Reviewboard Link:            
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Date Submitted:             2009-11-02 11:29 CST
Last Modified:              2011-01-18 11:45 CST
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Summary:                    Native bridging from a span that isn't the master
span can cause data corruption.
Description: 
If you configure two spans in your system, and setup a native bridge with
the span that isn't the master, it's possible for repeated/missing "chunks"
to appear in the bridged data stream.  This appears due to the master span
processing taking place asynchronously with the audio received on the the
span that you're actually interested in recording from.

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 (0130618) sruffell (administrator) - 2011-01-18 11:45
 https://issues.asterisk.org/view.php?id=16165#c130618 
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While looking at a recent regression, I think I (finally) saw the root
cause of this issue.

When a span is in conference, the confin and confout structures are used
to store up samples for the master span processing function and again for
the real transmit function.  Currently DAHDI_CB_SIZE is set to 2, so only
two milliseconds of data can be stored up.

If there are multiple spans, and the masterspan is *not* the span that
you're in conference with it's possible to overflow the confin and confout
buffers which results in duplicated samples being set out. 

Issue History 
Date Modified    Username       Field                    Change               
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2011-01-18 11:45 sruffell       Note Added: 0130618                          
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