--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gen-pdu/message.c	Sat Aug 05 07:43:45 2023 +0000
@@ -0,0 +1,142 @@
+/*
+ * This module implements TPDU encoding of actual messages, after all
+ * settings have been captured.
+ */
+
+#include <sys/types.h>
+#include <ctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include "error.h"
+
+extern int dir_mo, include_sca;
+extern u_char sc_addr[12], user_addr[12];
+extern u_char mr_byte, pid_byte, dcs_byte;
+extern u_char scts_buf[7];
+extern int is_septet, scts_is_set;
+
+extern int input_lineno;
+
+static void
+emit_first_octet(udhi)
+{
+	u_char fo;
+
+	if (dir_mo)
+		fo = 1;
+	else
+		fo = 0;
+	if (udhi)
+		fo |= 0x40;
+	printf("%02X", fo);
+}
+
+static void
+make_pdu(udl, ud_buf, ud_octets, udhi)
+	u_char *ud_buf;
+	unsigned udl, ud_octets;
+{
+	if (include_sca)
+		emit_hex_out(sc_addr, sc_addr[0] + 1, stdout);
+	emit_first_octet(udhi);
+	if (dir_mo)
+		printf("%02X", mr_byte);
+	emit_hex_out(user_addr, ((user_addr[0] + 1) >> 1) + 2, stdout);
+	printf("%02X", pid_byte);
+	printf("%02X", dcs_byte);
+	if (!dir_mo) {
+		if (!scts_is_set)
+			set_auto_scts();
+		emit_hex_out(scts_buf, 7, stdout);
+	}
+	printf("%02X", udl);
+	emit_hex_out(ud_buf, ud_octets, stdout);
+	putchar('\n');
+}
+
+static void
+cmd_msg_common(arg, udhi)
+	char *arg;
+{
+	u_char input[160], ud7[160], octbuf[140];
+	unsigned input_len, udhl, udhl1, udh_chars, plain_chars;
+	unsigned udl, udl_octets;
+
+	for (input_len = 0; ; input_len++) {
+		while (isspace(*arg))
+			arg++;
+		if (!*arg)
+			break;
+		if (!isxdigit(arg[0]) || !isxdigit(arg[1])) {
+			fprintf(stderr, ERR_PREFIX "invalid hex string\n",
+				input_lineno);
+			exit(1);
+		}
+		if (input_len >= 160) {
+toolong:		fprintf(stderr, ERR_PREFIX "hex string is too long\n",
+				input_lineno);
+			exit(1);
+		}
+		input[input_len] = (decode_hex_digit(arg[0]) << 4) |
+				    decode_hex_digit(arg[1]);
+		arg += 2;
+	}
+	if (!is_septet && input_len > 140)
+		goto toolong;
+	if (udhi) {
+		if (!input_len) {
+			fprintf(stderr, ERR_PREFIX
+				"empty message is invalid with UDHI\n",
+				input_lineno);
+			exit(1);
+		}
+		udhl = input[0];
+		udhl1 = udhl + 1;
+		if (udhl1 > input_len) {
+			fprintf(stderr, ERR_PREFIX "UDHL exceeds UD length\n",
+				input_lineno);
+			exit(1);
+		}
+	}
+	if (!is_septet) {
+		make_pdu(input_len, input, input_len, udhi);
+		return;
+	}
+	if (udhi)
+		udh_chars = (udhl1 * 8 + 6) / 7;
+	else {
+		udhl1 = 0;
+		udh_chars = 0;
+	}
+	plain_chars = input_len - udhl1;
+	udl = udh_chars + plain_chars;
+	if (udl > 160) {
+		fprintf(stderr, ERR_PREFIX
+			"message exceeds 160 septets after UDH\n",
+			input_lineno);
+		exit(1);
+	}
+	udl_octets = (udl * 7 + 7) / 8;
+	bzero(ud7, 160);
+	bcopy(input + udhl1, ud7 + udh_chars, plain_chars);
+	gsm7_pack(ud7, octbuf, udl_octets);
+	if (udhi)
+		bcopy(input, octbuf, udhl1);
+	make_pdu(udl, ud7, udl_octets, udhi);
+}
+
+void
+cmd_msg_plain(argc, argv)
+	char **argv;
+{
+	cmd_msg_common(argv[1], 0);
+}
+
+void
+cmd_msg_udh(argc, argv)
+	char **argv;
+{
+	cmd_msg_common(argv[1], 1);
+}