Fully abstract connection type

Abstract common interface of connection type, so Redis can hide the
implementation and uplayer only calls connection API without macro.

               uplayer
                  |
           connection layer
             /          \
          socket        TLS

Currently, for both socket and TLS, all the methods of connection type
are declared as static functions.

It's possible to build TLS(even socket) as a shared library, and Redis
loads it dynamically in the next step.

Also add helper function connTypeOfCluster() and
connTypeOfReplication() to simplify the code:
link->conn = server.tls_cluster ? connCreateTLS() : connCreateSocket();
-> link->conn = connCreate(connTypeOfCluster());

Signed-off-by: zhenwei pi <pizhenwei@bytedance.com>

1 files changed, 15 insertions, 0 deletions

diff --git a/src/connection.c b/src/connection.c
index e28257fab..72db82212 100644
--- a/src/connection.c
+++ b/src/connection.c
@@ -152,3 +152,18 @@ void *connTypeGetClientCtx(int type) {
 
     return NULL;
 }
+connection *connCreate(int type) {
+    ConnectionType *ct = connectionByType(type);
+
+    serverAssert(ct && ct->conn_create);
+
+    return ct->conn_create();
+}
+
+connection *connCreateAccepted(int type, int fd, void *priv) {
+    ConnectionType *ct = connectionByType(type);
+
+    serverAssert(ct && ct->conn_create_accepted);
+
+    return ct->conn_create_accepted(fd, priv);
+}