[asterisk-bugs] [Asterisk 0012592]: DTMF issues in 1.4.19 with missing digits

[noreply at bugs.digium.com]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=12592 
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Reported By:                dawebber
Assigned To:                
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Project:                    Asterisk
Issue ID:                   12592
Category:                   Channels/chan_zap
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     new
Asterisk Version:           1.4.19 
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Disclaimer on File?:        N/A 
Request Review:              
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Date Submitted:             05-06-2008 13:41 CDT
Last Modified:              05-12-2008 04:36 CDT
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Summary:                    DTMF issues in 1.4.19 with missing digits
Description: 
Trying to figure out an issue with DTMF recognition with 1.4.19. This  
is somewhat similar to the issue described here:  
http://bugs.digium.com/view.php?id=11740, but it might be a different  
issue altogether.

I have 1.4.19 running with TE212P on a US PRI hooked up to Time Warner
Telecom. DTMF debugging enabled.

LibPRI 1.4.3
Zaptel 1.4.9
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---------------------------------------------------------------------- 
 dimas - 05-12-08 04:36  
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Ohh.... 
It looks like you finally hit the scenario I was alwasy afraid of but
never encountered before. This is exactly why I consider the whole DTMF
normalization in ast_read a bad approach.

I guess we need attract Russel's attention to this issue. I believe bad
things happen because autoservice switches AST_FLAG_END_DTMF_ONLY mode back
and forth on the fly. So ast_read first reads DTMF_END in "normal" mode,
starts emulating BEGIN and then autoservice switches the channel to
AST_FLAG_END_DTMF_ONLY mode so when next DTMF_END is read it is passed
thru. So eventually, END of the third digit is read instead of the end of
the second. This obviously results in missing digits.

Mark, I'm about to attach very dirty patch you can test. I warn you that I
have NOT tested this patch myself and have no idea if it works at all or if
it breaks anything else. Use at your own risk. 

Issue History 
Date Modified   Username       Field                    Change               
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05-12-08 04:36  dimas          Note Added: 0086703                          
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