Merged revisions 207361 via svnmerge from

https://origsvn.digium.com/svn/asterisk/trunk

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  r207361 | russell | 2009-07-20 11:36:15 -0500 (Mon, 20 Jul 2009) | 16 lines
  
  Merged revisions 207360 via svnmerge from 
  https://origsvn.digium.com/svn/asterisk/branches/1.4
  
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    r207360 | russell | 2009-07-20 11:26:24 -0500 (Mon, 20 Jul 2009) | 9 lines
    
    Only do the chan->fdno check in ast_read() in a developer build.
    
    I changed this check to only happen in a dev-mode build.  I also added a
    comment explaining what is going on.  I also made it so that detection of
    this situation does not affect ast_read() operation.
    
    (closes issue #14723)
    Reported by: seadweller
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git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.6.0@207362 65c4cc65-6c06-0410-ace0-fbb531ad65f3

main/channel.c

@@ -2581,15 +2581,20 @@ static struct ast_frame *__ast_read(struct ast_channel *chan, int dropaudio)
 		goto done;
 	}
 
-	if (chan->fdno == -1) {
 #ifdef AST_DEVMODE
+	/* 
+	 * The ast_waitfor() code records which of the channel's file descriptors reported that
+	 * data is available.  In theory, ast_read() should only be called after ast_waitfor()
+	 * reports that a channel has data available for reading.  However, there still may be
+	 * some edge cases throughout the code where ast_read() is called improperly.  This can
+	 * potentially cause problems, so if this is a developer build, make a lot of noise if
+	 * this happens so that it can be addressed. 
+	 */
+	if (chan->fdno == -1) {
 		ast_log(LOG_ERROR, "ast_read() called with no recorded file descriptor.\n");
-#else
-		ast_debug(2, "ast_read() called with no recorded file descriptor.\n");
-#endif
-		f = &ast_null_frame;
-		goto done;
 	}
+#endif
+
 	prestate = chan->_state;
 
 	/* Read and ignore anything on the alertpipe, but read only