[asterisk-bugs] [Asterisk 0012777]: [patch] Pattern matching treats 'x' differently than 'X'

[noreply at bugs.digium.com]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=12777 
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Reported By:                jsmith
Assigned To:                
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Project:                    Asterisk
Issue ID:                   12777
Category:                   PBX/pbx_config
Reproducibility:            always
Severity:                   minor
Priority:                   high
Status:                     new
Asterisk Version:           SVN 
SVN Branch (only for SVN checkouts, not tarball releases):  1.4  
SVN Revision (number only!): 117582 
Disclaimer on File?:        N/A 
Request Review:              
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Date Submitted:             06-02-2008 21:50 CDT
Last Modified:              06-03-2008 11:44 CDT
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Summary:                    [patch] Pattern matching treats 'x' differently than
'X'
Description: 
Steve Edwards reported
[http://lists.digium.com/pipermail/asterisk-users/2008-June/212956.html]
that the pattern _2xxx is evaluated before _2[1-4]00.  I went to reply that
it shouldn't be that way, but in my testing, I found he was right.

I think this is a pretty serious bug in the pattern matching code.

As I understand it, Asterisk should be evaluating the patterns one digit
at a time, from left to right.  Whenever more than one pattern could
possibly match, the *most constrained* digit should match first.  In other
words, given these two patterns, if I dialed 1234, the first one should
match before the second, as it's a more constrained match in the third
digit (it matches two possible values, while the other matches three).

_12[3-4]X
_12[3-5]X

The problem arises in that Asterisk seems to be treating the wildcard 'X'
differently than 'x', and I can't figure out why.  Both of them should mean
"any digit 0 through 9", but apparently they don't.  See below for more
details:
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---------------------------------------------------------------------- 
 blitzrage - 06-03-08 11:44  
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Corydon76: Right, I guess I was speaking in terms of not being in favour of
option 2.

As for the _2xxx having a higher priority of _2[1-4]XX, and thus higher
than _2XXX I would say that would definitely be unintended behaviour, and
that _2xxx should have the same weight as _2XXX.

I agree this probably needs to go to the -dev mailing list, where I'll
express my opinions there :) 

Issue History 
Date Modified   Username       Field                    Change               
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06-03-08 11:44  blitzrage      Note Added: 0087724                          
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