--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/utils/themwi-check-own.c	Wed Dec 13 03:14:35 2023 +0000
@@ -0,0 +1,57 @@
+/*
+ * This utility performs a lookup in ThemWi number database to see
+ * if a given NANP number is owned by us.
+ */
+
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <syslog.h>
+#include "../include/number_db_v2.h"
+#include "../libnumdb2/lookup_func.h"
+
+main(argc, argv)
+	char **argv;
+{
+	char nanp[11];
+	struct owned_number_rec *rec;
+
+	if (argc != 2) {
+usage:		fprintf(stderr, "usage: %s 10-digit-number\n", argv[0]);
+		exit(1);
+	}
+	if (grok_number_string(argv[1], 1) != 10)
+		goto usage;
+	dehyphen_number_string(argv[1], nanp);
+	if (!is_nanp_valid_prefix(nanp)) {
+		fprintf(stderr, "error: number violates NANP rules\n");
+		exit(1);
+	}
+	openlog("themwi-check-own", 0, LOG_LOCAL5);
+	if (read_number_db() < 0) {
+		fprintf(stderr, "error reading number database\n");
+		exit(1);
+	}
+	rec = numdb_lookup_nanp(nanp);
+	printf("+1-%.3s-%.3s-%s is ", nanp, nanp+3, nanp+6);
+	if (!rec) {
+		puts("NOT owned by us");
+		exit(1);
+	}
+	fputs("locally owned, ", stdout);
+	switch (rec->usage & NUMBER_USAGE_MASK) {
+	case NUMBER_USAGE_TYPE_RSVD:
+		puts("reserved");
+		break;
+	case NUMBER_USAGE_TYPE_GSM_SUB:
+		puts("assigned to a GSM subscriber");
+		break;
+	case NUMBER_USAGE_TYPE_ALIAS:
+		printf("mapped to +1-%03u-%03u-%04u\n", rec->remap[0],
+			rec->remap[1], rec->remap[2]);
+		break;
+	default:
+		printf("unknown usage byte 0x%02X\n", rec->usage);
+	}
+	exit(0);
+}