fixes ast_transfer stall until hangup if called with a channel that doesn't support...

ast_transfer sets res to 0 if there is no technology transfer function,
but then tests for it to be negative before deciding to do an early exit.
As a result, it will will wait for an AST_CONTROL_TRANSFER message that
will never come.

(closes issue #16424)
Reported by: davidw
Patches:
      Issue_16424_trunk_234134.patch uploaded by davidw (license 780)

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@238492 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/main/channel.c b/main/channel.c
index cb30e14..bb78c76 100644 (file)
--- a/main/channel.c
+++ b/main/channel.c
@@ -4597,7 +4597,7 @@ int ast_transfer(struct ast_channel *chan, char *dest)
        }
        ast_channel_unlock(chan);
 
-       if (res < 0) {
+       if (res <= 0) {
                return res;
        }