--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/.hgignore	Tue Dec 12 23:52:50 2023 +0000
@@ -0,0 +1,3 @@
+syntax: regexp
+
+\.[oa]$

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/build-inc/themwi/nanp	Tue Dec 12 23:52:50 2023 +0000
@@ -0,0 +1,1 @@
+../../include
\ No newline at end of file

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/include/number_db_v2.h	Tue Dec 12 23:52:50 2023 +0000
@@ -0,0 +1,40 @@
+/*
+ * This header file defines version 2 of ThemWi number database
+ * binary file format.
+ */
+
+#pragma once
+
+#include <stdint.h>
+
+struct numdb_file_hdr {
+	uint32_t	owned_number_count;
+	uint32_t	short_number_count;
+};
+
+struct owned_number_rec {
+	uint16_t	number[3];	/* NPA-exchange-suffix breakdown */
+	uint8_t		number_flags;	/* properties of outside number */
+	uint8_t		usage;		/* usage inside ThemWi */
+	uint16_t	remap[3];	/* secondary remap number */
+};
+
+#define	NUMBER_FLAG_SMSPROV	0x01	/* provisioned for outside SMS */
+#define	NUMBER_FLAG_E911PROV	0x02	/* provisioned for E911 */
+
+#define	NUMBER_USAGE_MASK		0x0F
+#define	NUMBER_USAGE_TYPE_RSVD		0x00
+#define	NUMBER_USAGE_TYPE_GSM_SUB	0x01
+#define	NUMBER_USAGE_TYPE_ALIAS		0x02
+#define	NUMBER_USAGE_FLAG_E911_VIA	0x10
+
+struct short_number_rec {
+	uint16_t	short_num;
+	uint8_t		short_num_type;
+	uint8_t		fullnum_flags;
+	uint16_t	fullnum_prefix[2];
+};
+
+#define	SHORT_NUM_TYPE_ABBREV		0x01
+#define	SHORT_NUM_TYPE_ITN		0x02
+#define	SHORT_NUM_TYPE_TEST_SINK	0x03

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/include/number_lookup.h	Tue Dec 12 23:52:50 2023 +0000
@@ -0,0 +1,12 @@
+/*
+ * This header file provides function prototype declarations
+ * for numdb lookup library.
+ */
+
+#pragma once
+
+int read_number_db(void);
+int refresh_number_db(void);
+
+const struct owned_number_rec *numdb_lookup_nanp(const char *numstr);
+const struct short_number_rec *numdb_lookup_short(const char *numstr);

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/include/number_utils.h	Tue Dec 12 23:52:50 2023 +0000
@@ -0,0 +1,17 @@
+/*
+ * This header file provides function prototype declarations
+ * for phone-number-related utility functions.
+ */
+
+#pragma once
+
+#include <stdint.h>
+#include <stdbool.h>
+
+uint16_t digits3_to_uint16(const char *numstr);
+uint16_t digits4_to_uint16(const char *numstr);
+
+bool is_nanp_valid_prefix(const char *numstr);
+
+int grok_number_string(const char *str, bool allow_hyphen);
+void dehyphen_number_string(const char *src, char *dest);

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libnumutil/Makefile	Tue Dec 12 23:52:50 2023 +0000
@@ -0,0 +1,13 @@
+CC=	gcc
+CFLAGS=	-O2 -I../build-inc
+OBJS=	digit_groups.o nanp_valid.o numstring.o
+LIB=	libnumutil.a
+
+all:	${LIB}
+
+${LIB}:	${OBJS}
+	ar rcu $@ ${OBJS}
+	ranlib $@
+
+clean:
+	rm -f *.[oa] errs

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libnumutil/digit_groups.c	Tue Dec 12 23:52:50 2023 +0000
@@ -0,0 +1,31 @@
+/*
+ * In version 2 of ThemWi owned number database, NANP numbers are stored as 3
+ * uint16_t words: NPA, exchange and prefix, each uint16_t encoding a group of
+ * 3 or 4 digits of the full telephone number.  This library module provides
+ * functions for turning groups of 3 or 4 digits into uint16_t words.
+ */
+
+#include <stdint.h>
+
+#include <themwi/nanp/number_utils.h>
+
+uint16_t digits3_to_uint16(const char *str)
+{
+	int acc;
+
+	acc = (str[0] - '0') * 100;
+	acc += (str[1] - '0') * 10;
+	acc += str[2] - '0';
+	return acc;
+}
+
+uint16_t digits4_to_uint16(const char *str)
+{
+	int acc;
+
+	acc = (str[0] - '0') * 1000;
+	acc += (str[1] - '0') * 100;
+	acc += (str[2] - '0') * 10;
+	acc += str[3] - '0';
+	return acc;
+}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libnumutil/nanp_valid.c	Tue Dec 12 23:52:50 2023 +0000
@@ -0,0 +1,23 @@
+/*
+ * Utility functions for NANP number validation.
+ */
+
+#include <stdbool.h>
+
+#include <themwi/nanp/number_utils.h>
+
+bool is_nanp_valid_prefix(const char *s)
+{
+	/* validate NPA part */
+	if (s[0] < '2')
+		return false;
+	if (s[1] == '1' && s[2] == '1')
+		return false;
+	/* validate exchange part */
+	if (s[3] < '2')
+		return false;
+	if (s[4] == '1' && s[5] == '1')
+		return false;
+	/* all checks passed */
+	return true;
+}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libnumutil/numstring.c	Tue Dec 12 23:52:50 2023 +0000
@@ -0,0 +1,52 @@
+/*
+ * Utility functions for number string initial parsing or preening.
+ * grok_number_string() checks whether or not a user-supplied string
+ * argument is fully numeric (with possibility of allowing hyphens),
+ * and returns the number of digits.  dehyphen_number_string() copies
+ * a possibly-hyphenated number string to a new buffer with all hyphens
+ * taken out.
+ */
+
+#include <ctype.h>
+
+#include <themwi/nanp/number_utils.h>
+
+int grok_number_string(const char *str, bool allow_hyphen)
+{
+	const char *cp;
+	int c, n;
+	bool last_hyphen;
+
+	n = 0;
+	last_hyphen = false;
+	for (cp = str; *cp; ) {
+		c = *cp++;
+		if (isdigit(c)) {
+			n++;
+			last_hyphen = false;
+		} else if (c == '-') {
+			if (!allow_hyphen || !n || last_hyphen)
+				return(-1);
+			last_hyphen = true;
+		} else
+			return(-1);
+	}
+	if (last_hyphen)
+		return(-1);
+	return n;
+}
+
+void dehyphen_number_string(const char *src, char *dest)
+{
+	const char *cp;
+	char *dp;
+	int c;
+
+	dp = dest;
+	for (cp = src; *cp; ) {
+		c = *cp++;
+		if (isdigit(c))
+			*dp++ = c;
+	}
+	*dp = '\0';
+}