Round robin upstream added.

src/nxt_upstream.h

@@ -8,4 +8,74 @@
 #define _NXT_UPSTREAM_H_INCLUDED_
 
 
+typedef struct nxt_upstream_proxy_s            nxt_upstream_proxy_t;
+typedef struct nxt_upstream_round_robin_s      nxt_upstream_round_robin_t;
+typedef struct nxt_upstream_round_robin_server_s
+    nxt_upstream_round_robin_server_t;
+
+
+typedef void (*nxt_upstream_peer_ready_t)(nxt_task_t *task,
+    nxt_upstream_server_t *us);
+typedef void (*nxt_upstream_peer_error_t)(nxt_task_t *task,
+    nxt_upstream_server_t *us);
+
+
+typedef struct {
+    nxt_upstream_peer_ready_t                  ready;
+    nxt_upstream_peer_error_t                  error;
+} nxt_upstream_peer_state_t;
+
+
+typedef nxt_upstream_t *(*nxt_upstream_joint_create_t)(
+    nxt_router_temp_conf_t *tmcf, nxt_upstream_t *upstream);
+typedef void (*nxt_upstream_server_get_t)(nxt_task_t *task,
+    nxt_upstream_server_t *us);
+
+
+typedef struct {
+    nxt_upstream_joint_create_t                joint_create;
+    nxt_upstream_server_get_t                  get;
+} nxt_upstream_server_proto_t;
+
+
+struct nxt_upstream_s {
+    const nxt_upstream_server_proto_t          *proto;
+
+    union {
+        nxt_upstream_proxy_t                   *proxy;
+        nxt_upstream_round_robin_t             *round_robin;
+    } type;
+
+    nxt_str_t                                  name;
+};
+
+
+struct nxt_upstreams_s {
+    uint32_t                                   items;
+    nxt_upstream_t                             upstream[0];
+};
+
+
+struct nxt_upstream_server_s {
+    nxt_sockaddr_t                             *sockaddr;
+    const nxt_upstream_peer_state_t            *state;
+    nxt_upstream_t                             *upstream;
+
+    uint8_t                                    protocol;
+
+    union {
+        nxt_upstream_round_robin_server_t      *round_robin;
+    } server;
+
+    union {
+        nxt_http_peer_t                        *http;
+    } peer;
+};
+
+
+nxt_int_t nxt_upstream_round_robin_create(nxt_task_t *task,
+    nxt_router_temp_conf_t *tmcf, nxt_conf_value_t *upstream_conf,
+    nxt_upstream_t *upstream);
+
+
 #endif /* _NXT_UPSTREAM_H_INCLUDED_ */