Add force_user_invis extension from charybdis+sn.

Forces nonopers +i.

extensions/Makefile.in

@@ -37,6 +37,7 @@ SRCS =                          \
   extb_server.c			\
   extb_realname.c		\
   extb_extgecos.c		\
+  force_user_invis.c		\
   hurt.c			\
   ip_cloaking.c			\
   ip_cloaking_old.c		\

extensions/force_user_invis.c

@@ -0,0 +1,34 @@
+/*
+ * Deny user to remove +i flag except they are irc operators
+ *
+ * Based off no_oper_invis.c by jilles
+ *
+ */
+
+#include "stdinc.h"
+#include "modules.h"
+#include "client.h"
+#include "hook.h"
+#include "ircd.h"
+#include "send.h"
+#include "s_conf.h"
+#include "s_newconf.h"
+
+static void h_noi_umode_changed(hook_data_umode_changed *);
+
+mapi_hfn_list_av1 noi_hfnlist[] = {
+	{ "umode_changed", (hookfn) h_noi_umode_changed },
+	{ NULL, NULL }
+};
+
+DECLARE_MODULE_AV1(force_user_invis, NULL, NULL, NULL, NULL, noi_hfnlist, "1.0.0");
+
+static void
+h_noi_umode_changed(hook_data_umode_changed *hdata)
+{
+	struct Client *source_p = hdata->client;
+
+	if (MyClient(source_p) && !IsOper(source_p) && !IsInvisible(source_p)) {
+		SetInvisible(source_p);
+	}
+}