Multiple revisions 375993-375994

........
  r375993 | mmichelson | 2012-11-07 11:01:13 -0600 (Wed, 07 Nov 2012) | 30 lines
  
  Fix misuses of timeouts throughout the code.
  
  Prior to this change, a common method for determining if a timeout
  was reached was to call a function such as ast_waitfor_n() and inspect
  the out parameter that told how many milliseconds were left, then use
  that as the input to ast_waitfor_n() on the next go-around.
  
  The problem with this is that in some cases, submillisecond timeouts
  can occur, resulting in the out parameter not decreasing any. When this
  happens thousands of times, the result is that the timeout takes much
  longer than intended to be reached. As an example, I had a situation where
  a 3 second timeout took multiple days to finally end since most wakeups
  from ast_waitfor_n() were under a millisecond.
  
  This patch seeks to fix this pattern throughout the code. Now we log the
  time when an operation began and find the difference in wall clock time
  between now and when the event started. This means that sub-millisecond timeouts
  now cannot play havoc when trying to determine if something has timed out.
  
  Part of this fix also includes changing the function ast_waitfor() so that it
  is possible for it to return less than zero when a negative timeout is given
  to it. This makes it actually possible to detect errors in ast_waitfor() when
  there is no timeout.
  
  (closes issue ASTERISK-20414)
  reported by David M. Lee
  
  Review: https://reviewboard.asterisk.org/r/2135/
........
  r375994 | mmichelson | 2012-11-07 11:08:44 -0600 (Wed, 07 Nov 2012) | 3 lines
  
  Remove some debugging that accidentally made it in the last commit.
........

Merged revisions 375993-375994 from http://svn.asterisk.org/svn/asterisk/branches/1.8
........

Merged revisions 375995 from http://svn.asterisk.org/svn/asterisk/branches/10
........

Merged revisions 376014 from http://svn.asterisk.org/svn/asterisk/branches/11


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@376015 65c4cc65-6c06-0410-ace0-fbb531ad65f3

1 files changed, 14 insertions, 0 deletions

diff --git a/include/asterisk/time.h b/include/asterisk/time.h
index 4fa08723b..dd68db704 100644
--- a/include/asterisk/time.h
+++ b/include/asterisk/time.h
@@ -152,6 +152,20 @@ struct timeval ast_tvadd(struct timeval a, struct timeval b);
 struct timeval ast_tvsub(struct timeval a, struct timeval b);
 
 /*!
+ * \brief Calculate remaining milliseconds given a starting timestamp
+ * and upper bound
+ *
+ * If the upper bound is negative, then this indicates that there is no
+ * upper bound on the amount of time to wait. This will result in a
+ * negative return.
+ *
+ * \param start When timing started being calculated
+ * \param max_ms The maximum number of milliseconds to wait from start. May be negative.
+ * \return The number of milliseconds left to wait for. May be negative.
+ */
+int ast_remaining_ms(struct timeval start, int max_ms);
+
+/*!
  * \brief Returns a timeval from sec, usec
  */
 AST_INLINE_API(