main/untils: Prevent potential infinite loop in ast_careful_fwrite
authorMatthew Jordan <mjordan@digium.com>
Thu, 3 Jul 2014 11:27:25 +0000 (11:27 +0000)
committerMatthew Jordan <mjordan@digium.com>
Thu, 3 Jul 2014 11:27:25 +0000 (11:27 +0000)
commitd1c6a9e69ed7fedfe2b61e8cd99093011573f587
tree14b0573dcfeb8e0da03a3e1c7c9ba5a32d431757
parenta69e0cd32a208d077a3b0fcb2d7d21846a711a89
main/untils: Prevent potential infinite loop in ast_careful_fwrite

A loop in ast_careful_fwrite exists that will continually attempt to write to
a file stream, even in the presence of EAGAIN/EINTR errors. However, if a
connection that uses ast_careful_fwrite closes suddenly, ast_careful_fwrite's
call to fflush may return EAGAIN/EINTER along with EOF. A subsequent call to
fflush will return EOF but not clear errno, resulting in an infinite loop.

This patch clears errno after it is detected and handled the loop, such that
any subsequent call to fflush will not get erroneously stuck.

Review: https://reviewboard.asterisk.org/r/3704

#ASTERISK-23984 #close
Reported by: Steve Davies
patches:
  fflush_loop_fix uploaded by one47 (License 5012)
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Merged revisions 417797 from http://svn.asterisk.org/svn/asterisk/branches/1.8
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Merged revisions 417798 from http://svn.asterisk.org/svn/asterisk/branches/11
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Merged revisions 417799 from http://svn.asterisk.org/svn/asterisk/branches/12

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@417800 65c4cc65-6c06-0410-ace0-fbb531ad65f3
main/utils.c