conncache: move the connection counter to the cache struct

The static connection counter caused a race condition. Moving the
connection id counter into conncache solves it, as well as simplifying
the related logic.

1 files changed, 1 insertions, 0 deletions

diff --git a/lib/conncache.h b/lib/conncache.h
index f5e41f187..691f061f9 100644
--- a/lib/conncache.h
+++ b/lib/conncache.h
@@ -25,6 +25,7 @@
 struct conncache {
   struct curl_hash *hash;
   size_t num_connections;
+  size_t next_connection_id;
 };
 
 struct conncache *Curl_conncache_init(int size);