broadband-modem-qmi,broadband-modem-mbim: always use SMS_PART_INVALID_INDEX unstored parts

MMSmsList has logic to allow multiple unstored messages as long as
they use SMS_PART_INVALID_INDEX. These messages aren't stored so
they don't have an index.

But the MBIM and QMI modems used index 0 for unstored messages,
meaning there could only ever be one and also that multipart
messages would fail to be combined.

Let's fix that by just using SMS_PART_INVALID_INDEX for every
scenario where an unstored message comes in.

Fixes: https://gitlab.freedesktop.org/mobile-broadband/ModemManager/-/issues/979

Signed-off-by: Dan Williams <dan@ioncontrol.co>

src/tests/meson.build

@@ -10,6 +10,7 @@ test_units = {
   'modem-helpers': libhelpers_dep,
   'sms-part-3gpp': libhelpers_dep,
   'sms-part-cdma': libhelpers_dep,
+  'sms-list': libsms_dep,
   'udev-rules': libkerneldevice_dep,
 }
 

src/tests/test-sms-list.c

@@ -0,0 +1,140 @@
+/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details:
+ *
+ * Copyright (C) 2025 Dan Williams <dan@ioncontrol.co>
+ */
+
+#include <glib.h>
+#include <glib-object.h>
+#include <string.h>
+#include <stdio.h>
+#include <locale.h>
+
+#define _LIBMM_INSIDE_MM
+#include <libmm-glib.h>
+
+#include "mm-sms-part-3gpp.h"
+#include "mm-sms-list.h"
+#include "mm-log-test.h"
+#include "mm-base-modem.h"
+
+#include "mm-iface-modem-messaging.h"
+
+/****************************************************************/
+
+static void
+test_mbim_multipart_unstored (void)
+{
+    static const gchar *part1_pdu =
+        "07912160130300f4440b915155685703f900005240713104738a3e050003c40202da6f37881e96"
+        "9fcbf4b4fb0ccabfeb20f4fb0ea287e5e7323ded3e83dae17519747fcbd96490b95c6683d27310"
+        "1d5d0601";
+    static const gchar *part2_pdu =
+        "07912160130300f4440b915155685703f900005240713104738aa0050003c40201ac69373d7c2e"
+        "83e87538bc2cbf87e565d039dc2e83c220769a4e6797416132394d4fbfdda0fb5b4e4783c2ee3c"
+        "888e2e83e86fd0db0c1a86e769f71b647eb3d9ef7bda7d06a5e7a0b09b0c9ab3df74109c1dce83"
+        "e8e8301d44479741f9771d949e83e861f9b94c4fbbcf20f13b4c9f83e8e832485c068ddfedf6db"
+        "0da2a3cba0fcbb0e1abfdb";
+    MMSmsPart *part1, *part2;
+    MMSmsList *list;
+    MMBaseSms *sms1, *sms2;
+    GError *error = NULL;
+
+    /* Some MBIM devices (Dell 5821e) report SMSes via the MBIM_CID_SMS_READ
+     * unsolicited notification usually used for Class-0 (flash/alert) messages.
+     * These always have a message index of 0; thus when a multipart SMS
+     * arrives it comes as two individual notifications both with 0 indexes.
+     * The MBIM modem code used SMS_PART_INVALID_INDEX for unstored SMSes.
+     * Ensure the MMSmsList can handle combining the two parts with the same
+     * index.
+     */
+    part1 = mm_sms_part_3gpp_new_from_pdu (SMS_PART_INVALID_INDEX, part1_pdu, NULL, &error);
+    g_assert_no_error (error);
+    part2 = mm_sms_part_3gpp_new_from_pdu (SMS_PART_INVALID_INDEX, part2_pdu, NULL, &error);
+    g_assert_no_error (error);
+
+    list = mm_sms_list_new (NULL);
+
+    sms1 = MM_BASE_SMS (g_object_new (MM_TYPE_BASE_SMS,
+                                      MM_BASE_SMS_IS_3GPP, TRUE,
+                                      MM_BASE_SMS_DEFAULT_STORAGE, MM_SMS_STORAGE_MT,
+                                      NULL));
+    mm_sms_list_take_part (list,
+                           sms1,
+                           part1,
+                           MM_SMS_STATE_RECEIVED,
+                           MM_SMS_STORAGE_MT,
+                           &error);
+    g_assert_no_error (error);
+
+    sms2 = MM_BASE_SMS (g_object_new (MM_TYPE_BASE_SMS,
+                                      MM_BASE_SMS_IS_3GPP, TRUE,
+                                      MM_BASE_SMS_DEFAULT_STORAGE, MM_SMS_STORAGE_MT,
+                                      NULL));
+    mm_sms_list_take_part (list,
+                           sms2,
+                           part2,
+                           MM_SMS_STATE_RECEIVED,
+                           MM_SMS_STORAGE_MT,
+                           &error);
+    g_assert_no_error (error);
+
+    g_assert_cmpint (mm_sms_list_get_count (list), ==, 1);
+}
+
+/****************************************************************/
+
+static void
+test_mbim_multipart_zero_index (void)
+{
+    static const gchar *pdu =
+        "07912160130300f4440b915155685703f900005240713104738a3e050003c40202da6f37881e96"
+        "9fcbf4b4fb0ccabfeb20f4fb0ea287e5e7323ded3e83dae17519747fcbd96490b95c6683d27310"
+        "1d5d0601";
+    MMSmsPart *part;
+    MMSmsList *list;
+    MMBaseSms *sms;
+    GError *error = NULL;
+
+    part = mm_sms_part_3gpp_new_from_pdu (0, pdu, NULL, &error);
+    g_assert_no_error (error);
+
+    list = mm_sms_list_new (NULL);
+
+    sms = MM_BASE_SMS (g_object_new (MM_TYPE_BASE_SMS,
+                                     MM_BASE_SMS_IS_3GPP, TRUE,
+                                     MM_BASE_SMS_DEFAULT_STORAGE, MM_SMS_STORAGE_MT,
+                                     NULL));
+    mm_sms_list_take_part (list,
+                           sms,
+                           part,
+                           MM_SMS_STATE_RECEIVED,
+                           MM_SMS_STORAGE_MT,
+                           &error);
+    g_assert_no_error (error);
+
+    g_assert_cmpint (mm_sms_list_get_count (list), ==, 1);
+}
+
+/****************************************************************/
+
+int main (int argc, char **argv)
+{
+    setlocale (LC_ALL, "");
+
+    g_test_init (&argc, &argv, NULL);
+
+    g_test_add_func ("/MM/SMS/3GPP/sms-list/zero-index", test_mbim_multipart_zero_index);
+    g_test_add_func ("/MM/SMS/3GPP/sms-list/mbim-multipart-unstored", test_mbim_multipart_unstored);
+
+    return g_test_run ();
+}