+extern RRDHOST *rrdhost_find_by_hostname(const char *hostname, uint32_t hash);
+extern RRDHOST *rrdhost_find_by_guid(const char *guid, uint32_t hash);
+
+extern RRDHOST *rrdhost_find_or_create(
+ const char *hostname
+ , const char *guid
+ , const char *os
+ , int update_every
+ , long history
+ , RRD_MEMORY_MODE mode
+ , int health_enabled
+ , int rrdpush_enabled
+ , char *rrdpush_destination
+ , char *rrdpush_api_key
+);
+
+#if defined(NETDATA_INTERNAL_CHECKS) && defined(NETDATA_VERIFY_LOCKS)
+extern void __rrdhost_check_wrlock(RRDHOST *host, const char *file, const char *function, const unsigned long line);
+extern void __rrdhost_check_rdlock(RRDHOST *host, const char *file, const char *function, const unsigned long line);
+extern void __rrdset_check_rdlock(RRDSET *st, const char *file, const char *function, const unsigned long line);
+extern void __rrdset_check_wrlock(RRDSET *st, const char *file, const char *function, const unsigned long line);
+extern void __rrd_check_rdlock(const char *file, const char *function, const unsigned long line);
+extern void __rrd_check_wrlock(const char *file, const char *function, const unsigned long line);
+
+#define rrdhost_check_rdlock(host) __rrdhost_check_rdlock(host, __FILE__, __FUNCTION__, __LINE__)
+#define rrdhost_check_wrlock(host) __rrdhost_check_wrlock(host, __FILE__, __FUNCTION__, __LINE__)
+#define rrdset_check_rdlock(st) __rrdset_check_rdlock(st, __FILE__, __FUNCTION__, __LINE__)
+#define rrdset_check_wrlock(st) __rrdset_check_wrlock(st, __FILE__, __FUNCTION__, __LINE__)
+#define rrd_check_rdlock() __rrd_check_rdlock(__FILE__, __FUNCTION__, __LINE__)
+#define rrd_check_wrlock() __rrd_check_wrlock(__FILE__, __FUNCTION__, __LINE__)