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

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: http://svn.digium.com/svn/asterisk/trunk@238492 f38db490-d61c-443f-a65b-d21fe96a405b

1 files changed, 1 insertions, 1 deletions

diff --git a/main/channel.c b/main/channel.c
index cb30e1449..bb78c76fa 100644
--- 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;
 	}