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

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@207360 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/main/channel.c b/main/channel.c
index 67aa766364319734871ce40d123e87e9e75364b9..f548d0e6b085eee7cfcd824c4f2345236809ad2a 100644 (file)
--- a/main/channel.c
+++ b/main/channel.c
@@ -2080,17 +2080,20 @@ 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
-               if (option_debug > 1) {
-                       ast_log(LOG_DEBUG, "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