session server UPDATE new callback for CH new session fail

Author: michalvasko

src/session_p.h

@@ -670,6 +670,9 @@ struct nc_server_ch_thread_arg {
     void *ctx_cb_data;                                      /**< acq/rel cb data */
     int (*new_session_cb)(const char *client_name, struct nc_session *new_session, void *user_data);    /**< creating new session cb */
     void *new_session_cb_data;                              /**< new session cb data */
+    void (*new_session_fail_cb)(const char *client_name, const char *endpt_name, uint8_t max_attempts,
+            uint8_t cur_attempt, void *user_data);          /**< failed to create a new session cb */
+    void *new_session_fail_cb_data;                         /**< new session fail cb data */
 
     int thread_running;         /**< A boolean value that is truthy while the underlying Call Home thread is running */
     pthread_mutex_t cond_lock;  /**< Condition's lock used for signalling the thread to terminate */
@@ -793,6 +796,8 @@ struct nc_server_opts {
         void *ctx_cb_data;                                      /**< Data passed to the callbacks above. */
         nc_server_ch_new_session_cb new_session_cb;             /**< New session callback. */
         void *new_session_cb_data;                              /**< Data passed to the new_session_cb callback. */
+        nc_server_ch_new_session_fail_cb new_session_fail_cb;   /**< New session fail callback, */
+        void *new_session_fail_cb_data;                         /**< Data passed to the new_session_fail_cb callback. */
     } ch_dispatch_data;
 
     struct {

src/session_server.c

@@ -255,6 +255,22 @@ nc_server_ch_set_dispatch_data(nc_server_ch_session_acquire_ctx_cb acquire_ctx_c
     nc_rwlock_unlock(&server_opts.config_lock, __func__);
 }
 
+API void
+nc_server_ch_set_new_session_fail_cb(nc_server_ch_new_session_fail_cb new_session_fail_cb,
+        void *new_session_fail_cb_data)
+{
+    /* CONFIG WRITE LOCK */
+    if (nc_rwlock_lock(&server_opts.config_lock, NC_RWLOCK_WRITE, NC_CONFIG_LOCK_TIMEOUT, __func__) != 1) {
+        return;
+    }
+
+    server_opts.ch_dispatch_data.new_session_fail_cb = new_session_fail_cb;
+    server_opts.ch_dispatch_data.new_session_fail_cb_data = new_session_fail_cb_data;
+
+    /* CONFIG WRITE UNLOCK */
+    nc_rwlock_unlock(&server_opts.config_lock, __func__);
+}
+
 #endif
 
 int
@@ -3291,7 +3307,7 @@ nc_ch_client_thread(void *arg)
 {
     struct nc_server_ch_thread_arg *data = arg;
     NC_MSG_TYPE msgtype;
-    uint8_t cur_attempts = 0;
+    uint8_t cur_attempts = 0, max_attempts;
     uint16_t next_endpt_index, max_wait;
     char *cur_endpt_name = NULL;
     struct nc_ch_endpt *cur_endpt;
@@ -3416,11 +3432,19 @@ nc_ch_client_thread(void *arg)
             }
         } else {
             /* session was not created, wait a little bit and try again */
+            ++cur_attempts;
             max_wait = client->max_wait;
+            max_attempts = client->max_attempts;
 
             /* CONFIG READ UNLOCK */
             nc_rwlock_unlock(&server_opts.config_lock, __func__);
 
+            /* failed connection attempt */
+            if (data->new_session_fail_cb) {
+                data->new_session_fail_cb(data->client_name, cur_endpt_name, max_attempts, cur_attempts,
+                        data->new_session_fail_cb_data);
+            }
+
             /* wait for max_wait seconds */
             if (!nc_server_ch_client_thread_is_running_wait(session, data, max_wait)) {
                 /* thread should stop running */
@@ -3439,8 +3463,6 @@ nc_ch_client_thread(void *arg)
                 goto cleanup_unlock;
             }
 
-            ++cur_attempts;
-
             /* try to find our endpoint again */
             LY_ARRAY_FOR(client->ch_endpts, next_endpt_index) {
                 if (!strcmp(client->ch_endpts[next_endpt_index].name, cur_endpt_name)) {
@@ -3555,6 +3577,8 @@ _nc_connect_ch_client_dispatch(const struct nc_ch_client *ch_client, nc_server_c
     arg->ctx_cb_data = ctx_cb_data;
     arg->new_session_cb = new_session_cb;
     arg->new_session_cb_data = new_session_cb_data;
+    arg->new_session_fail_cb = server_opts.ch_dispatch_data.new_session_fail_cb;
+    arg->new_session_fail_cb_data = server_opts.ch_dispatch_data.new_session_fail_cb_data;
     pthread_cond_init(&arg->cond, NULL);
     pthread_mutex_init(&arg->cond_lock, NULL);
 

src/session_server_ch.h

@@ -91,6 +91,18 @@ typedef void (*nc_server_ch_session_release_ctx_cb)(void *cb_data);
  */
 typedef int (*nc_server_ch_new_session_cb)(const char *client_name, struct nc_session *new_session, void *user_data);
 
+/**
+ * @brief Callback for failures when creating new Call Home sessions.
+ *
+ * @param[in] client_name Name of the CH client that failed to create the session.
+ * @param[in] endpt_name Name of the CH client endpoint that failed to create the session.
+ * @param[in] max_attemps Maximum connection attempts for the endpoints.
+ * @param[in] cur_attempt Current failed connection attempt.
+ * @param[in] user_data Arbitrary new session callback data.
+ */
+typedef void (*nc_server_ch_new_session_fail_cb)(const char *client_name, const char *endpt_name, uint8_t max_attempts,
+        uint8_t cur_attempt, void *user_data);
+
 /**
  * @brief Dispatch a thread connecting to a listening NETCONF client and creating Call Home sessions.
  *
@@ -121,6 +133,15 @@ void nc_server_ch_set_dispatch_data(nc_server_ch_session_acquire_ctx_cb acquire_
         nc_server_ch_session_release_ctx_cb release_ctx_cb, void *ctx_cb_data, nc_server_ch_new_session_cb new_session_cb,
         void *new_session_cb_data);
 
+/**
+ * @brief Set callback for failure of a new CH session creation.
+ *
+ * @param[in] new_session_fail_cb Callback to call for every failed session creation.
+ * @param[in] new_session_fail_cb_data Arbitrary user data passed to @p new_session_fail_cb.
+ */
+void nc_server_ch_set_new_session_fail_cb(nc_server_ch_new_session_fail_cb new_session_fail_cb,
+        void *new_session_fail_cb_data);
+
 /** @} Server-side Call Home Functions */
 
 #endif /* NC_ENABLED_SSH_TLS */