--- a/.hgignore	Thu Jun 13 02:32:11 2024 +0000
+++ b/.hgignore	Thu Jun 13 02:39:21 2024 +0000
@@ -3,5 +3,7 @@
 \.[oa]$
 ^config\.defs$
 
+^decode/pcm-sms-decode$
+^decode/sms-pdu-decode$
 ^enc-text/sms-encode-text$
 ^gen-pdu/sms-gen-tpdu$

--- a/Makefile	Thu Jun 13 02:32:11 2024 +0000
+++ b/Makefile	Thu Jun 13 02:39:21 2024 +0000
@@ -1,10 +1,11 @@
-PROGDIR=enc-text gen-pdu scripts
+PROGDIR=decode enc-text gen-pdu scripts
 LIBDIR=	libcoding
 SUBDIR=	${PROGDIR} ${LIBDIR}
 DESTDIR=
 
 all:	${SUBDIR}
 
+decode:		libcoding
 enc-text:	libcoding
 gen-pdu:	libcoding
 

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/decode/Makefile	Thu Jun 13 02:39:21 2024 +0000
@@ -0,0 +1,21 @@
+PROGS=	pcm-sms-decode sms-pdu-decode
+LIB=	../libcoding/libcoding.a
+OBJS0=	pcm-sms-decode.o pdu-common.o ${LIB}
+OBJS1=	pdu-common.o sms-pdu-decode.o ${LIB}
+
+include ../config.defs
+
+all:	${PROGS}
+
+pcm-sms-decode:	${OBJS0}
+	${CC} ${CFLAGS} -o $@ ${OBJS0}
+
+sms-pdu-decode:	${OBJS1}
+	${CC} ${CFLAGS} -o $@ ${OBJS1}
+
+install:
+	mkdir -p ${DESTDIR}${bindir}
+	install -c ${PROGS} ${DESTDIR}${bindir}
+
+clean:
+	rm -f ${PROGS} *.o *errs *.out

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/decode/pcm-sms-decode.c	Thu Jun 13 02:39:21 2024 +0000
@@ -0,0 +1,78 @@
+#include <sys/types.h>
+#include <ctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <unistd.h>
+
+extern int ascii_ext_mode, global_hexdump_mode;
+extern u_char pdu[176];
+extern unsigned pdu_length;
+
+static char *infname;
+static FILE *inf;
+static unsigned start_recno;
+
+static char *msgtype[4] = {"received", "received unread", "sent",
+			   "stored unsent"};
+
+static
+process_cmdline(argc, argv)
+	char **argv;
+{
+	int c;
+	extern int optind;
+
+	while ((c = getopt(argc, argv, "ehsu")) != EOF)
+		switch (c) {
+		case 'e':
+			ascii_ext_mode = 1;
+			continue;
+		case 'h':
+			global_hexdump_mode = 1;
+			continue;
+		case 's':
+			start_recno = 1;
+			continue;
+		case 'u':
+			ascii_ext_mode = 2;
+			continue;
+		default:
+			fprintf(stderr, "%s: invalid option\n", argv[0]);
+			exit(1);
+		}
+	if (argc != optind + 1) {
+		fprintf(stderr, "usage: %s [options] pcm-sms-binfile\n",
+			argv[0]);
+		exit(1);
+	}
+	infname = argv[optind];
+}
+
+main(argc, argv)
+	char **argv;
+{
+	u_char record[176];
+	unsigned recno;
+
+	process_cmdline(argc, argv);
+	inf = fopen(infname, "r");
+	if (!inf) {
+		perror(infname);
+		exit(1);
+	}
+	pdu_length = 176;
+	for (recno = start_recno; fread(record, sizeof record, 1, inf);
+	     recno++) {
+		if (record[0] & 1) {
+			printf("Record #%u is %s message:\n", recno,
+				msgtype[(record[0] >> 1) & 3]);
+			bcopy(record + 1, pdu, 175);
+			process_pdu(0, 1);
+			putchar('\n');
+		} else
+			printf("Record #%u is empty\n\n", recno);
+	}
+	exit(0);
+}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/decode/pdu-common.c	Thu Jun 13 02:39:21 2024 +0000
@@ -0,0 +1,391 @@
+#include <sys/types.h>
+#include <ctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+
+int ascii_ext_mode, global_hexdump_mode;
+
+u_char pdu[176];
+unsigned pdu_length;
+
+static u_char first_octet;
+static unsigned pdu_ptr;
+static int dcs_distilled;
+
+static
+handle_sca()
+{
+	unsigned sca_len;
+	char digits[21];
+
+	sca_len = pdu[0];
+	pdu_ptr = 1;
+	if (!sca_len)
+		return(0);
+	if (sca_len < 2 || sca_len > 11) {
+		printf("Decode-Error: invalid SCA length\n");
+		return(-1);
+	}
+	if (pdu_ptr + sca_len > pdu_length) {
+		printf("Decode-Error: SCA goes past PDU end\n");
+		return(-1);
+	}
+	pdu_ptr += sca_len;
+	decode_address_digits(pdu + 2, digits, sc_addr_ndigits(pdu));
+	printf("SCA: %s%s (type 0x%02X)\n", pdu[1] == 0x91 ? "+" : "", digits,
+		pdu[1]);
+	return(0);
+}
+
+static
+handle_first_octet()
+{
+	if (pdu_ptr >= pdu_length) {
+		printf("Decode-Error: end of PDU before FO\n");
+		return(-1);
+	}
+	first_octet = pdu[pdu_ptr++];
+	printf("First-Octet: 0x%02X\n", first_octet);
+	return(0);
+}
+
+static
+handle_mr()
+{
+	if (pdu_ptr >= pdu_length) {
+		printf("Decode-Error: end of PDU before MR\n");
+		return(-1);
+	}
+	printf("MR: 0x%02X\n", pdu[pdu_ptr++]);
+	return(0);
+}
+
+static
+handle_user_addr(direction)
+	char *direction;
+{
+	unsigned addr_field_len, alpha_nsep;
+	char digits[21];
+	u_char alpha_gsm7[11];
+
+	if (pdu_ptr >= pdu_length) {
+		printf("Decode-Error: end of PDU before %s address\n",
+			direction);
+		return(-1);
+	}
+	if (pdu[pdu_ptr] > 20) {
+		printf("Decode-Error: %s address > 20 digits\n", direction);
+		return(-1);
+	}
+	addr_field_len = ((pdu[pdu_ptr] + 1) >> 1) + 2;
+	if (pdu_ptr + addr_field_len > pdu_length) {
+		printf("Decode-Error: %s address goes past PDU end\n",
+			direction);
+		return(-1);
+	}
+	if (!pdu[pdu_ptr])
+		printf("%s: empty-addr (type 0x%02X)\n", direction,
+			pdu[pdu_ptr+1]);
+	else if ((pdu[pdu_ptr+1] & 0x70) == 0x50 &&
+		 alpha_addr_valid(pdu[pdu_ptr], &alpha_nsep)) {
+		gsm7_unpack(pdu + pdu_ptr + 2, alpha_gsm7, alpha_nsep);
+		printf("%s: ", direction);
+		print_gsm7_string_to_file(alpha_gsm7, alpha_nsep, stdout);
+		printf(" (type 0x%02X)\n", pdu[pdu_ptr+1]);
+	} else {
+		decode_address_digits(pdu + pdu_ptr + 2, digits, pdu[pdu_ptr]);
+		printf("%s: %s%s (type 0x%02X)\n", direction,
+			pdu[pdu_ptr+1] == 0x91 ? "+" : "", digits,
+			pdu[pdu_ptr+1]);
+	}
+	pdu_ptr += addr_field_len;
+	return(0);
+}
+
+static
+handle_pid()
+{
+	if (pdu_ptr >= pdu_length) {
+		printf("Decode-Error: end of PDU before PID\n");
+		return(-1);
+	}
+	printf("PID: 0x%02X\n", pdu[pdu_ptr++]);
+	return(0);
+}
+
+static
+handle_dcs()
+{
+	u_char dcs;
+	char *strtype;
+
+	if (pdu_ptr >= pdu_length) {
+		printf("Decode-Error: end of PDU before DCS\n");
+		return(-1);
+	}
+	dcs = pdu[pdu_ptr++];
+	dcs_distilled = sms_dcs_classify(dcs);
+	switch (dcs_distilled) {
+	case 7:
+		strtype = "7-bit";
+		break;
+	case 8:
+		strtype = "raw octets";
+		break;
+	case 9:
+		strtype = "compressed";
+		break;
+	case 16:
+		strtype = "UCS-2";
+		break;
+	}
+	printf("DCS: 0x%02X (%s)\n", dcs, strtype);
+	return(0);
+}
+
+static
+handle_scts()
+{
+	char str[21];
+
+	if (pdu_ptr + 7 > pdu_length) {
+		printf("Decode-Error: end of PDU before SCTS\n");
+		return(-1);
+	}
+	gsm_timestamp_decode(pdu + pdu_ptr, str);
+	printf("SC-Timestamp: %s\n", str);
+	pdu_ptr += 7;
+	return(0);
+}
+
+static
+handle_vp_abs()
+{
+	char str[21];
+
+	if (pdu_ptr + 7 > pdu_length) {
+		printf("Decode-Error: end of PDU before VP-abs\n");
+		return(-1);
+	}
+	gsm_timestamp_decode(pdu + pdu_ptr, str);
+	printf("VP-Absolute: %s\n", str);
+	pdu_ptr += 7;
+	return(0);
+}
+
+static
+handle_vp_rel()
+{
+	unsigned vprel, hours, min;
+
+	if (pdu_ptr >= pdu_length) {
+		printf("Decode-Error: end of PDU before VP-rel\n");
+		return(-1);
+	}
+	vprel = pdu[pdu_ptr++];
+	if (vprel <= 143) {
+		min = (vprel + 1) * 5;
+		goto hhmm;
+	} else if (vprel <= 167) {
+		min = (vprel - 143) * 30 + 12 * 60;
+		goto hhmm;
+	} else if (vprel <= 196) {
+		printf("VP-Relative: %u days\n", vprel - 166);
+		return(0);
+	} else {
+		printf("VP-Relative: %u weeks\n", vprel - 192);
+		return(0);
+	}
+
+hhmm:	hours = min / 60;
+	min %= 60;
+	printf("VP-Relative:");
+	if (hours)
+		printf(" %u hour%s", hours, hours != 1 ? "s" : "");
+	if (min)
+		printf(" %u min", min);
+	putchar('\n');
+	return(0);
+}
+
+static
+handle_vp_enh()
+{
+	if (pdu_ptr + 7 > pdu_length) {
+		printf("Decode-Error: end of PDU before VP-enh\n");
+		return(-1);
+	}
+	printf("VP-Enhanced: %02X %02X %02X %02X %02X %02X %02X\n",
+		pdu[pdu_ptr], pdu[pdu_ptr+1], pdu[pdu_ptr+2], pdu[pdu_ptr+3],
+		pdu[pdu_ptr+4], pdu[pdu_ptr+5], pdu[pdu_ptr+6]);
+	pdu_ptr += 7;
+	return(0);
+}
+
+static
+handle_vp()
+{
+	int rc;
+
+	switch (first_octet & 0x18) {
+	case 0x00:
+		rc = 0;
+		break;
+	case 0x08:
+		rc = handle_vp_enh();
+		break;
+	case 0x10:
+		rc = handle_vp_rel();
+		break;
+	case 0x18:
+		rc = handle_vp_abs();
+		break;
+	}
+	return(rc);
+}
+
+process_pdu(require_exact_length, expect_sca)
+{
+	unsigned udl, udl_octets;
+	unsigned udhl, udh_octets, udh_chars, ud_chars;
+	u_char ud7[160], decode_buf[481];
+	int do_hexdump;
+	unsigned decoded_len;
+
+	if (expect_sca) {
+		if (handle_sca() < 0)
+			return(-1);
+	} else
+		pdu_ptr = 0;
+	if (handle_first_octet() < 0)
+		return(-1);
+	if (first_octet & 2) {
+		printf("Decode-Error: MTI not supported\n");
+		return(-1);
+	}
+	if (first_octet & 1) {
+		if (handle_mr() < 0)
+			return(-1);
+	}
+	if (handle_user_addr(first_octet & 1 ? "To" : "From") < 0)
+		return(-1);
+	if (handle_pid() < 0)
+		return(-1);
+	if (handle_dcs() < 0)
+		return(-1);
+	if (first_octet & 1) {
+		if (handle_vp() < 0)
+			return(-1);
+	} else {
+		if (handle_scts() < 0)
+			return(-1);
+	}
+	if (pdu_ptr >= pdu_length) {
+		printf("Decode-Error: end of PDU before UDL\n");
+		return(-1);
+	}
+	udl = pdu[pdu_ptr++];
+	if (dcs_distilled == 7) {
+		if (udl > 160) {
+			printf("Decode-Error: UDL %u > 160\n", udl);
+			return(-1);
+		}
+		udl_octets = (udl * 7 + 7) / 8;
+	} else {
+		if (udl > 140) {
+			printf("Decode-Error: UDL %u > 140\n", udl);
+			return(-1);
+		}
+		udl_octets = udl;
+	}
+	if (require_exact_length && pdu_length - pdu_ptr != udl_octets) {
+		printf("Decode-Error: UD length in PDU %u != expected %u\n",
+			pdu_length - pdu_ptr, udl_octets);
+		return(-1);
+	}
+	if (first_octet & 0x40) {
+		if (!udl) {
+			printf("Decode-Error: UDHI set with UDL=0\n");
+			return(-1);
+		}
+		udhl = pdu[pdu_ptr];
+		udh_octets = udhl + 1;
+		if (udh_octets > udl_octets) {
+			printf("Decode-Error: UDHL exceeds UDL\n");
+			return(-1);
+		}
+		printf("UDH-Length: %u\n", udhl);
+		if (dcs_distilled == 7)
+			udh_chars = (udh_octets * 8 + 6) / 7;
+		else
+			udh_chars = udh_octets;
+	} else {
+		udhl = 0;
+		udh_octets = 0;
+		udh_chars = 0;
+	}
+	if (udh_chars >= udl) {
+		ud_chars = 0;
+		printf("Length: 0\n");
+	} else {
+		ud_chars = udl - udh_chars;
+		if (dcs_distilled == 7)
+			gsm7_unpack(pdu + pdu_ptr, ud7, udl);
+		if (global_hexdump_mode)
+			do_hexdump = 1;
+		else switch (dcs_distilled) {
+		case 7:
+			do_hexdump = 0;
+			break;
+		case 8:
+		case 9:
+			do_hexdump = 1;
+			break;
+		case 16:
+			if (ud_chars & 1)
+				do_hexdump = 1;
+			else
+				do_hexdump = 0;
+			break;
+		}
+		if (do_hexdump)
+			printf("Length: %u (raw)\n", ud_chars);
+		else {
+			switch (dcs_distilled) {
+			case 7:
+				gsm7_to_ascii_or_ext(ud7 + udh_chars, ud_chars,
+						     decode_buf, &decoded_len,
+						     ascii_ext_mode, 1);
+				break;
+			case 16:
+				ucs2_to_ascii_or_ext(pdu + pdu_ptr + udh_chars,
+						     ud_chars,
+						     decode_buf, &decoded_len,
+						     ascii_ext_mode, 1);
+				break;
+			}
+			printf("Length: %u", ud_chars);
+			if (decoded_len != ud_chars)
+				printf("->%u", decoded_len);
+			putchar('\n');
+		}
+	}
+
+	if (udhl) {
+		printf("\nUDH:\n");
+		msg_bits_hexdump(pdu + pdu_ptr + 1, udhl);
+	}
+	if (!ud_chars)
+		return(0);
+	putchar('\n');
+	if (do_hexdump) {
+		if (dcs_distilled == 7)
+			msg_bits_hexdump(ud7 + udh_chars, ud_chars);
+		else
+			msg_bits_hexdump(pdu + pdu_ptr + udh_chars, ud_chars);
+	} else
+		puts(decode_buf);
+	return(0);
+}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/decode/sms-pdu-decode.c	Thu Jun 13 02:39:21 2024 +0000
@@ -0,0 +1,99 @@
+#include <sys/types.h>
+#include <ctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <unistd.h>
+
+extern int ascii_ext_mode, global_hexdump_mode;
+extern u_char pdu[176];
+extern unsigned pdu_length;
+
+static char *infname;
+static FILE *inf;
+static int keep_raw_pdu, pdu_has_sca = 1;
+
+static char input_line[1024];
+
+static
+process_cmdline(argc, argv)
+	char **argv;
+{
+	int c;
+	extern int optind;
+
+	while ((c = getopt(argc, argv, "ehnpu")) != EOF)
+		switch (c) {
+		case 'e':
+			ascii_ext_mode = 1;
+			continue;
+		case 'h':
+			global_hexdump_mode = 1;
+			continue;
+		case 'n':
+			pdu_has_sca = 0;
+			continue;
+		case 'p':
+			keep_raw_pdu = 1;
+			continue;
+		case 'u':
+			ascii_ext_mode = 2;
+			continue;
+		default:
+			fprintf(stderr, "%s: invalid option\n", argv[0]);
+			exit(1);
+		}
+	if (argc > optind)
+		infname = argv[optind];
+}
+
+static
+swallow_empty_line()
+{
+	int c;
+
+	c = getc(inf);
+	if (c != '\n')
+		ungetc(c, inf);
+}
+
+main(argc, argv)
+	char **argv;
+{
+	char *nl;
+	int lineno, cc;
+
+	process_cmdline(argc, argv);
+	if (infname) {
+		inf = fopen(infname, "r");
+		if (!inf) {
+			perror(infname);
+			exit(1);
+		}
+	} else {
+		inf = stdin;
+		infname = "stdin";
+	}
+	for (lineno = 1; fgets(input_line, sizeof input_line, inf); lineno++) {
+		nl = index(input_line, '\n');
+		if (!nl) {
+			fprintf(stderr, "%s line %d: no newline\n",
+				infname, lineno);
+			exit(1);
+		}
+		*nl = '\0';
+		cc = decode_hex_line(input_line, pdu, sizeof pdu);
+		if (cc <= 0) {
+			puts(input_line);
+			continue;
+		}
+		pdu_length = cc;
+		if (keep_raw_pdu)
+			printf("%s\n\n", input_line);
+		process_pdu(1, pdu_has_sca);
+		putchar('\n');
+		swallow_empty_line();
+	}
+	exit(0);
+}