this may fix cloudwu#744

cloudwu · cloudwu · commit 1c605bed2b2e · 2017-10-04T00:11:31.000+08:00
diff --git a/3rd/jemalloc b/3rd/jemalloc
@@ -1 +1 @@
-Subproject commit 896ed3a8b3f41998d4fb4d625d30ac63ef2d51fb
+Subproject commit 3541a904d6fb949f3f0aea05418ccce7cbd4b705
diff --git a/skynet-src/socket_server.c b/skynet-src/socket_server.c
@@ -698,6 +698,8 @@ send_buffer_(struct socket_server *ss, struct socket *s, struct socket_lock *l,
 				raise_uncomplete(s);
 				return -1;
 			}
+			if (s->low.head)
+				return -1;
 		} 
 		// step 4
 		assert(send_buffer_empty(s) && s->wb_size == 0);

Original file line number	Diff line number	Diff line change
`@@ -698,6 +698,8 @@ send_buffer_(struct socket_server ss, struct socket s, struct socket_lock *l,`
`698`	`698`	`raise_uncomplete(s);`
`699`	`699`	`return -1;`
`700`	`700`	`}`
	`701`	`+ if (s->low.head)`
	`702`	`+ return -1;`
`701`	`703`	`}`
`702`	`704`	`// step 4`
`703`	`705`	`assert(send_buffer_empty(s) && s->wb_size == 0);`