[asterisk-bugs] [Asterisk 0016032]: [patch] AGI returns bogus "510 Invalid or unknown command"

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=16032 
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Reported By:                notahat
Assigned To:                
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Project:                    Asterisk
Issue ID:                   16032
Category:                   Resources/res_agi
Reproducibility:            random
Severity:                   minor
Priority:                   normal
Status:                     ready for review
Asterisk Version:           SVN 
JIRA:                        
Regression:                 No 
Reviewboard Link:            
SVN Branch (only for SVN checkouts, not tarball releases):  trunk 
SVN Revision (number only!): 222530 
Request Review:              
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Date Submitted:             2009-10-06 21:19 CDT
Last Modified:              2011-01-19 12:37 CST
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Summary:                    [patch] AGI returns bogus "510 Invalid or unknown
command"
Description: 
When res_agi.c reads from the AGI stream, it incorrectly calculates the
number of free bytes remaining in the read buffer. In certain circumstances
(such as repeated EAGAIN errors from fgets), this causes it to incorrectly
interpret the buffer as full. That then confuses the code interpreting the
command, leading to a bogus "510 invalid or unknown command" error being
returned.
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 (0130713) svnbot (reporter) - 2011-01-19 12:37
 https://issues.asterisk.org/view.php?id=16032#c130713 
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Repository: asterisk
Revision: 302548

U   branches/1.6.2/res/res_agi.c

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r302548 | seanbright | 2011-01-19 12:37:10 -0600 (Wed, 19 Jan 2011) | 10
lines

Properly handle partial reads from fgets() when handling AGIs.

When fgets() failed with EAGAIN, we were continually decrementing the
available
space left in our buffer, resulting in botched command handling.

(closes issue https://issues.asterisk.org/view.php?id=16032)
Reported by: notahat
Patches:
      agi_buffer_patch2.diff uploaded by fnordian (license 110)

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http://svn.digium.com/view/asterisk?view=rev&revision=302548 

Issue History 
Date Modified    Username       Field                    Change               
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2011-01-19 12:37 svnbot         Note Added: 0130713                          
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