Replace multiple strcat and strcpy by snprintf

Patch by Florian Obser

doc/ChangeLog

@@ -1,3 +1,6 @@
+3 April 2024: Jeroen
+	- Replace multiple strcat and strcpy by snprintf.
+
 26 March 2024: Jeroen
 	- Test if debug is available in do-tests.
 	- Enforce timeout from NSD in ixfr_gone test.

doc/RELNOTES

@@ -54,6 +54,7 @@ BUG FIXES:
 	- Update expressions in ixfr_and_restart test.
 	- Make algorithm explicit in control-repattern test.
 	- Switch algorithm to hmac-256 for testplan_mess test.
+	- Replace multiple strcat and strcpy by snprintf.
 
 4.8.0
 ================

options.c

@@ -463,14 +463,13 @@ zone_list_member_zone_insert(struct nsd_options* opt, const char* nm,
 			"zone value provided in zone '%s' or pattern '%s'",
 			mem_idnm, nm, patnm);
 
-	else if(strlen(pat->catalog_producer_zone)
-	      + strlen(mem_idnm) + 9 > sizeof(member_id_str))
+	else if(snprintf(member_id_str, sizeof(member_id_str),
+	    "%s.zones.%s", mem_idnm, pat->catalog_producer_zone) >=
+	    (int)sizeof(member_id_str))
 		log_msg(LOG_ERR, "syntax error in member ID '%s.zones.%s' for "
 			"zone '%s'", mem_idnm, pat->catalog_producer_zone, nm);
 
-	else if(!(cmz->member_id = dname_parse(opt->region, strcat(strcat(
-				strcpy(member_id_str, mem_idnm),".zones."),
-					pat->catalog_producer_zone))))
+	else if(!(cmz->member_id = dname_parse(opt->region, member_id_str)))
 		log_msg(LOG_ERR, "parse error in member ID '%s' for "
 			"zone '%s'", member_id_str, nm);
 	return zone;