connid is unsigned; offset real conns by maxrid + 1

servers/slapd/connection.c

@@ -48,7 +48,7 @@ static ldap_pvt_thread_mutex_t connections_mutex;
 static Connection *connections = NULL;
 
 static ldap_pvt_thread_mutex_t conn_nextid_mutex;
-static unsigned long conn_nextid = 0;
+static unsigned long conn_nextid = SLAPD_SYNC_SYNCCONN_OFFSET;
 
 static const char conn_lost_str[] = "connection lost";
 

servers/slapd/slap.h

@@ -1701,13 +1701,15 @@ typedef BackendDB Backend;
 
 struct syncinfo_s;
 
-/* fake conn connid constructed as SLAPD_SYNC_CONN_OFFSET - rid */
-#define SLAPD_SYNC_SYNCCONN_OFFSET (-1000)
-#define SLAPD_SYNC_IS_SYNCCONN(connid) ((connid) <= SLAPD_SYNC_SYNCCONN_OFFSET)
-#define SLAPD_SYNC_RID2SYNCCONN(rid) (SLAPD_SYNC_SYNCCONN_OFFSET - (rid))
-
 #define SLAP_SYNC_RID_MAX	999
 #define SLAP_SYNC_SID_MAX	4095	/* based on liblutil/csn.c field width */
+
+/* fake conn connid constructed as rid; real connids start
+ * at SLAPD_SYNC_CONN_OFFSET */
+#define SLAPD_SYNC_SYNCCONN_OFFSET (SLAP_SYNC_RID_MAX + 1)
+#define SLAPD_SYNC_IS_SYNCCONN(connid) ((connid) < SLAPD_SYNC_SYNCCONN_OFFSET)
+#define SLAPD_SYNC_RID2SYNCCONN(rid) (rid)
+
 #define SLAP_SYNCUUID_SET_SIZE 256
 
 struct sync_cookie {