simtech: handle non-standard '+CRING' URCs

The SIM7600E ends up emitting these URCs with too many <CR>s, and the
generic +CRING handler doesn't catch them, interfering with other
actions, e.g.:

  $ sudo mmcli --call 1 --accept
  error: couldn't accept the call: 'GDBus.Error:org.freedesktop.ModemManager1.Error.Core.Failed: Couldn't accept the call: Unhandled response '+CRING: VOICE

  +CRING: VOICE''

4 files changed, 92 insertions, 0 deletions

diff --git a/plugins/simtech/mm-modem-helpers-simtech.c b/plugins/simtech/mm-modem-helpers-simtech.c
index 5926c44f..331853d8 100644
--- a/plugins/simtech/mm-modem-helpers-simtech.c
+++ b/plugins/simtech/mm-modem-helpers-simtech.c
@@ -148,3 +148,16 @@ out:
 
     return TRUE;
 }
+
+/*****************************************************************************/
+
+/*
+ * Using TWO <CR> instead of one...
+ * <CR><CR><LF>+CRING: VOICE<CR><CR><LF>
+ */
+GRegex *
+mm_simtech_get_cring_urc_regex (void)
+{
+    return g_regex_new ("(?:\\r)+\\n\\+CRING:\\s*(\\S+)(?:\\r)+\\n",
+                        G_REGEX_RAW | G_REGEX_OPTIMIZE, 0, NULL);
+}
diff --git a/plugins/simtech/mm-modem-helpers-simtech.h b/plugins/simtech/mm-modem-helpers-simtech.h
index 1a046f58..b003b029 100644
--- a/plugins/simtech/mm-modem-helpers-simtech.h
+++ b/plugins/simtech/mm-modem-helpers-simtech.h
@@ -45,4 +45,9 @@ gboolean  mm_simtech_parse_voice_call_urc     (GMatchInfo  *match_info,
                                                guint       *duration,
                                                GError     **error);
 
+/*****************************************************************************/
+/* Non-standard CRING URC helpers */
+
+GRegex *mm_simtech_get_cring_urc_regex (void);
+
 #endif  /* MM_MODEM_HELPERS_SIMTECH_H */
diff --git a/plugins/simtech/mm-shared-simtech.c b/plugins/simtech/mm-shared-simtech.c
index 5a54ba44..45869c31 100644
--- a/plugins/simtech/mm-shared-simtech.c
+++ b/plugins/simtech/mm-shared-simtech.c
@@ -53,11 +53,13 @@ typedef struct {
     FeatureSupport         clcc_urc_support;
     GRegex                *clcc_urc_regex;
     GRegex                *voice_call_regex;
+    GRegex                *cring_regex;
 } Private;
 
 static void
 private_free (Private *ctx)
 {
+    g_regex_unref (ctx->cring_regex);
     g_regex_unref (ctx->voice_call_regex);
     g_regex_unref (ctx->clcc_urc_regex);
     g_slice_free (Private, ctx);
@@ -80,6 +82,7 @@ get_private (MMSharedSimtech *self)
         priv->clcc_urc_support = FEATURE_SUPPORT_UNKNOWN;
         priv->clcc_urc_regex = mm_simtech_get_clcc_urc_regex ();
         priv->voice_call_regex = mm_simtech_get_voice_call_urc_regex ();
+        priv->cring_regex = mm_simtech_get_cring_urc_regex ();
 
         /* Setup parent class' MMIfaceModemLocation and MMIfaceModemVoice */
 
@@ -830,6 +833,27 @@ voice_call_urc_received (MMPortSerialAt  *port,
 }
 
 static void
+cring_urc_received (MMPortSerialAt  *port,
+                    GMatchInfo      *info,
+                    MMSharedSimtech *self)
+{
+    MMCallInfo  call_info;
+    gchar      *str;
+
+    /* We could have "VOICE" or "DATA". Now consider only "VOICE" */
+    str = mm_get_string_unquoted_from_match_info (info, 1);
+    mm_dbg ("Ringing (%s)", str);
+    g_free (str);
+
+    call_info.index     = 0;
+    call_info.direction = MM_CALL_DIRECTION_INCOMING;
+    call_info.state     = MM_CALL_STATE_RINGING_IN;
+    call_info.number    = NULL;
+
+    mm_iface_modem_voice_report_call (MM_IFACE_MODEM_VOICE (self), &call_info);
+}
+
+static void
 common_voice_setup_cleanup_unsolicited_events (MMSharedSimtech *self,
                                                gboolean         enable)
 {
@@ -858,6 +882,12 @@ common_voice_setup_cleanup_unsolicited_events (MMSharedSimtech *self,
                                                        enable ? (MMPortSerialAtUnsolicitedMsgFn)voice_call_urc_received : NULL,
                                                        enable ? self : NULL,
                                                        NULL);
+
+        mm_port_serial_at_add_unsolicited_msg_handler (ports[i],
+                                                       priv->cring_regex,
+                                                       enable ? (MMPortSerialAtUnsolicitedMsgFn)cring_urc_received : NULL,
+                                                       enable ? self : NULL,
+                                                       NULL);
     }
 }
 
diff --git a/plugins/simtech/tests/test-modem-helpers-simtech.c b/plugins/simtech/tests/test-modem-helpers-simtech.c
index 3092e936..0274ae92 100644
--- a/plugins/simtech/tests/test-modem-helpers-simtech.c
+++ b/plugins/simtech/tests/test-modem-helpers-simtech.c
@@ -193,6 +193,47 @@ test_voice_call_end_duration_urc (void)
 
 /*****************************************************************************/
 
+static void
+common_test_cring_urc (const gchar *urc,
+                       const gchar *expected_type)
+{
+    GError     *error = NULL;
+    GRegex     *cring_regex = NULL;
+    GMatchInfo *match_info = NULL;
+    gchar      *type;
+    gboolean    result;
+
+    cring_regex = mm_simtech_get_cring_urc_regex ();
+
+    /* Same matching logic as done in MMSerialPortAt when processing URCs! */
+    result = g_regex_match_full (cring_regex, urc, -1, 0, 0, &match_info, &error);
+    g_assert_no_error (error);
+    g_assert (result);
+
+    type = g_match_info_fetch (match_info, 1);
+    g_assert (type);
+
+    g_assert_cmpstr (type, ==, expected_type);
+
+    g_match_info_free (match_info);
+    g_regex_unref (cring_regex);
+    g_free (type);
+}
+
+static void
+test_cring_urc_two_crs (void)
+{
+    common_test_cring_urc ("\r\r\n+CRING: VOICE\r\r\n", "VOICE");
+}
+
+static void
+test_cring_urc_one_cr (void)
+{
+    common_test_cring_urc ("\r\n+CRING: VOICE\r\n", "VOICE");
+}
+
+/*****************************************************************************/
+
 void
 _mm_log (const char *loc,
          const char *func,
@@ -227,5 +268,8 @@ int main (int argc, char **argv)
     g_test_add_func ("/MM/simtech/voicecall/urc/end",          test_voice_call_end_urc);
     g_test_add_func ("/MM/simtech/voicecall/urc/end-duration", test_voice_call_end_duration_urc);
 
+    g_test_add_func ("/MM/simtech/cring/urc/two-crs", test_cring_urc_two_crs);
+    g_test_add_func ("/MM/simtech/cring/urc/one-cr", test_cring_urc_one_cr);
+
     return g_test_run ();
 }