From c713c2c5f9ef8b1e674833932e9b91fbcca97050 Mon Sep 17 00:00:00 2001
From: Aleksander Morgado <aleksander@aleksander.es>
Date: Thu, 27 Jun 2019 14:03:19 +0200
Subject: [PATCH] api,voice: new HoldAndAccept() method

This method will put the currently active call on hold, and right away
accept the next available call.

The user of the API does not need to specify explicitly which is the
next call to accept, because that is decided automatically:
  * If there is any waiting call, it will accept it right away.
  * If there is no waiting call but there is a held call, it will make
  the held call active again.
---
 cli/mmcli-modem-voice.c                       |  49 ++++++
 .../libmm-glib/libmm-glib-sections.txt        |   7 +
 ....freedesktop.ModemManager1.Modem.Voice.xml |  17 ++
 libmm-glib/mm-modem-voice.c                   |  79 ++++++++++
 libmm-glib/mm-modem-voice.h                   |  11 ++
 src/mm-iface-modem-voice.c                    | 146 ++++++++++++++++++
 src/mm-iface-modem-voice.h                    |   8 +
 7 files changed, 317 insertions(+)

diff --git a/cli/mmcli-modem-voice.c b/cli/mmcli-modem-voice.c
index f1d24e16..e1f1426a 100644
--- a/cli/mmcli-modem-voice.c
+++ b/cli/mmcli-modem-voice.c
@@ -50,6 +50,7 @@ static Context *ctx;
 static gboolean list_flag;
 static gchar *create_str;
 static gchar *delete_str;
+static gboolean hold_and_accept_flag;
 static gboolean hangup_and_accept_flag;
 
 static GOptionEntry entries[] = {
@@ -65,6 +66,10 @@ static GOptionEntry entries[] = {
       "Delete a call from a given modem",
       "[PATH|INDEX]"
     },
+    { "voice-hold-and-accept", 0, 0, G_OPTION_ARG_NONE, &hold_and_accept_flag,
+      "Places all active calls in hold and accepts the next waiting or held call",
+      NULL
+    },
     { "voice-hangup-and-accept", 0, 0, G_OPTION_ARG_NONE, &hangup_and_accept_flag,
       "Hangs up all active calls and accepts the next waiting or held call",
       NULL
@@ -99,6 +104,7 @@ mmcli_modem_voice_options_enabled (void)
     n_actions = (list_flag +
                  !!create_str +
                  !!delete_str +
+                 hold_and_accept_flag +
                  hangup_and_accept_flag);
 
     if (n_actions > 1) {
@@ -206,6 +212,31 @@ hangup_and_accept_ready (MMModemVoice *modem,
     mmcli_async_operation_done ();
 }
 
+static void
+hold_and_accept_process_reply (const GError *error)
+{
+    if (error) {
+        g_printerr ("error: couldn't hold and accept: '%s'\n",
+                    error->message);
+        exit (EXIT_FAILURE);
+    }
+
+    g_print ("operation successful\n");
+}
+
+static void
+hold_and_accept_ready (MMModemVoice *modem,
+                         GAsyncResult *result,
+                         gpointer     nothing)
+{
+    GError *error = NULL;
+
+    mm_modem_voice_hold_and_accept_finish (modem, result, &error);
+    hold_and_accept_process_reply (error);
+
+    mmcli_async_operation_done ();
+}
+
 static void
 list_process_reply (GList        *result,
                     const GError *error)
@@ -365,6 +396,16 @@ get_modem_ready (GObject      *source,
         return;
     }
 
+    /* Request to hold and accept? */
+    if (hold_and_accept_flag) {
+        g_debug ("Asynchronously holding and accepting next call...");
+        mm_modem_voice_hold_and_accept (ctx->modem_voice,
+                                          ctx->cancellable,
+                                          (GAsyncReadyCallback)hold_and_accept_ready,
+                                          NULL);
+        return;
+    }
+
     /* Request to hangup and accept? */
     if (hangup_and_accept_flag) {
         g_debug ("Asynchronously hanging up and accepting next call...");
@@ -471,6 +512,14 @@ mmcli_modem_voice_run_synchronous (GDBusConnection *connection)
         return;
     }
 
+    /* Request to hold and accept? */
+    if (hold_and_accept_flag) {
+        g_debug ("Synchronously holding and accepting call...");
+        mm_modem_voice_hold_and_accept_sync (ctx->modem_voice, NULL, &error);
+        hold_and_accept_process_reply (error);
+        return;
+    }
+
     /* Request to hangup and accept? */
     if (hangup_and_accept_flag) {
         g_debug ("Synchronously hanging up and accepting call...");
diff --git a/docs/reference/libmm-glib/libmm-glib-sections.txt b/docs/reference/libmm-glib/libmm-glib-sections.txt
index 65ba689d..a2087f38 100644
--- a/docs/reference/libmm-glib/libmm-glib-sections.txt
+++ b/docs/reference/libmm-glib/libmm-glib-sections.txt
@@ -1015,6 +1015,9 @@ mm_modem_voice_list_calls_sync
 mm_modem_voice_hangup_and_accept
 mm_modem_voice_hangup_and_accept_finish
 mm_modem_voice_hangup_and_accept_sync
+mm_modem_voice_hold_and_accept
+mm_modem_voice_hold_and_accept_finish
+mm_modem_voice_hold_and_accept_sync
 <SUBSECTION Standard>
 MMModemVoiceClass
 MMModemVoicePrivate
@@ -2841,6 +2844,9 @@ mm_gdbus_modem_voice_call_list_calls_sync
 mm_gdbus_modem_voice_call_hangup_and_accept
 mm_gdbus_modem_voice_call_hangup_and_accept_finish
 mm_gdbus_modem_voice_call_hangup_and_accept_sync
+mm_gdbus_modem_voice_call_hold_and_accept
+mm_gdbus_modem_voice_call_hold_and_accept_finish
+mm_gdbus_modem_voice_call_hold_and_accept_sync
 <SUBSECTION Private>
 mm_gdbus_modem_voice_set_calls
 mm_gdbus_modem_voice_emit_call_added
@@ -2849,6 +2855,7 @@ mm_gdbus_modem_voice_complete_create_call
 mm_gdbus_modem_voice_complete_delete_call
 mm_gdbus_modem_voice_complete_list_calls
 mm_gdbus_modem_voice_complete_hangup_and_accept
+mm_gdbus_modem_voice_complete_hold_and_accept
 mm_gdbus_modem_voice_interface_info
 mm_gdbus_modem_voice_override_properties
 <SUBSECTION Standard>
diff --git a/introspection/org.freedesktop.ModemManager1.Modem.Voice.xml b/introspection/org.freedesktop.ModemManager1.Modem.Voice.xml
index 37b70260..b6c16f13 100644
--- a/introspection/org.freedesktop.ModemManager1.Modem.Voice.xml
+++ b/introspection/org.freedesktop.ModemManager1.Modem.Voice.xml
@@ -63,6 +63,23 @@
       <arg name="path" type="o" direction="out" />
     </method>
 
+    <!--
+        HoldAndAccept:
+
+        Place all active calls on hold, if any, and accept the next
+        call.
+
+        Waiting calls have preference over held calls, so the next
+        call being active will be any waiting call, or otherwise,
+        any held call.
+
+        The user should monitor the state of all available ongoing
+        calls to be reported of which one becomes active.
+
+        No error is returned if there are no waiting or held calls.
+    -->
+    <method name="HoldAndAccept" />
+
     <!--
         HangupAndAccept:
 
diff --git a/libmm-glib/mm-modem-voice.c b/libmm-glib/mm-modem-voice.c
index 19846602..8d86f718 100644
--- a/libmm-glib/mm-modem-voice.c
+++ b/libmm-glib/mm-modem-voice.c
@@ -532,6 +532,85 @@ mm_modem_voice_delete_call_sync (MMModemVoice *self,
 
 /*****************************************************************************/
 
+/**
+ * mm_modem_voice_hold_and_accept_finish:
+ * @self: A #MMModemVoice.
+ * @res: The #GAsyncResult obtained from the #GAsyncReadyCallback passed to mm_modem_voice_hold_and_accept().
+ * @error: Return location for error or %NULL.
+ *
+ * Finishes an operation started with mm_modem_voice_hold_and_accept().
+ *
+ * Returns: %TRUE if the operation was successful, %FALSE if @error is set.
+ * Since: 1.12
+ */
+gboolean
+mm_modem_voice_hold_and_accept_finish (MMModemVoice  *self,
+                                       GAsyncResult  *res,
+                                       GError       **error)
+{
+    g_return_val_if_fail (MM_IS_MODEM_VOICE (self), FALSE);
+
+    return mm_gdbus_modem_voice_call_hold_and_accept_finish (MM_GDBUS_MODEM_VOICE (self), res, error);
+}
+
+/**
+ * mm_modem_voice_hold_and_accept:
+ * @self: A #MMModemVoice.
+ * @cancellable: (allow-none): A #GCancellable or %NULL.
+ * @callback: A #GAsyncReadyCallback to call when the request is satisfied or %NULL.
+ * @user_data: User data to pass to @callback.
+ *
+ * Asynchronously puts all active calls on hold and accepts the next waiting or held call.
+ *
+ * When the operation is finished, @callback will be invoked in the <link linkend="g-main-context-push-thread-default">thread-default main loop</link> of the thread you are calling this method from.
+ * You can then call mm_modem_voice_hold_and_accept_finish() to get the result of the operation.
+ *
+ * See mm_modem_voice_hold_and_accept_sync() for the synchronous, blocking version of this method.
+ *
+ * Since: 1.12
+ */
+void
+mm_modem_voice_hold_and_accept (MMModemVoice        *self,
+                                GCancellable        *cancellable,
+                                GAsyncReadyCallback  callback,
+                                gpointer             user_data)
+{
+    g_return_if_fail (MM_IS_MODEM_VOICE (self));
+
+    mm_gdbus_modem_voice_call_hold_and_accept (MM_GDBUS_MODEM_VOICE (self),
+                                               cancellable,
+                                               callback,
+                                               user_data);
+}
+
+/**
+ * mm_modem_voice_hold_and_accept_sync:
+ * @self: A #MMModemVoice.
+ * @cancellable: (allow-none): A #GCancellable or %NULL.
+ * @error: Return location for error or %NULL.
+ *
+ * Synchronously puts all active calls on hold and accepts the next waiting or held call.
+ *
+ * The calling thread is blocked until a reply is received. See mm_modem_voice_hold_and_accept()
+ * for the asynchronous version of this method.
+ *
+ * Returns: %TRUE if the operation was successful, %FALSE if @error is set.
+ * Since: 1.12
+ */
+gboolean
+mm_modem_voice_hold_and_accept_sync (MMModemVoice  *self,
+                                     GCancellable  *cancellable,
+                                     GError       **error)
+{
+    g_return_val_if_fail (MM_IS_MODEM_VOICE (self), FALSE);
+
+    return mm_gdbus_modem_voice_call_hold_and_accept_sync (MM_GDBUS_MODEM_VOICE (self),
+                                                           cancellable,
+                                                           error);
+}
+
+/*****************************************************************************/
+
 /**
  * mm_modem_voice_hangup_and_accept_finish:
  * @self: A #MMModemVoice.
diff --git a/libmm-glib/mm-modem-voice.h b/libmm-glib/mm-modem-voice.h
index 18e13e04..ebc2493f 100644
--- a/libmm-glib/mm-modem-voice.h
+++ b/libmm-glib/mm-modem-voice.h
@@ -110,6 +110,17 @@ gboolean mm_modem_voice_delete_call_sync    (MMModemVoice *self,
                                              GCancellable *cancellable,
                                              GError **error);
 
+void     mm_modem_voice_hold_and_accept         (MMModemVoice        *self,
+                                                 GCancellable        *cancellable,
+                                                 GAsyncReadyCallback  callback,
+                                                 gpointer             user_data);
+gboolean mm_modem_voice_hold_and_accept_finish  (MMModemVoice        *self,
+                                                 GAsyncResult        *res,
+                                                 GError             **error);
+gboolean mm_modem_voice_hold_and_accept_sync    (MMModemVoice        *self,
+                                                 GCancellable        *cancellable,
+                                                 GError             **error);
+
 void     mm_modem_voice_hangup_and_accept         (MMModemVoice        *self,
                                                    GCancellable        *cancellable,
                                                    GAsyncReadyCallback  callback,
diff --git a/src/mm-iface-modem-voice.c b/src/mm-iface-modem-voice.c
index 7d5afa4b..c3e0f677 100644
--- a/src/mm-iface-modem-voice.c
+++ b/src/mm-iface-modem-voice.c
@@ -544,6 +544,148 @@ handle_list (MmGdbusModemVoice *skeleton,
 
 /*****************************************************************************/
 
+typedef struct {
+    MmGdbusModemVoice     *skeleton;
+    GDBusMethodInvocation *invocation;
+    MMIfaceModemVoice     *self;
+    GList                 *active_calls;
+    MMBaseCall            *next_call;
+} HandleHoldAndAcceptContext;
+
+static void
+handle_hold_and_accept_context_free (HandleHoldAndAcceptContext *ctx)
+{
+    g_list_free_full (ctx->active_calls, g_object_unref);
+    g_clear_object (&ctx->next_call);
+    g_object_unref (ctx->skeleton);
+    g_object_unref (ctx->invocation);
+    g_object_unref (ctx->self);
+    g_slice_free (HandleHoldAndAcceptContext, ctx);
+}
+
+static void
+hold_and_accept_ready (MMIfaceModemVoice          *self,
+                       GAsyncResult               *res,
+                       HandleHoldAndAcceptContext *ctx)
+{
+    GError *error = NULL;
+    GList  *l;
+
+    if (!MM_IFACE_MODEM_VOICE_GET_INTERFACE (self)->hold_and_accept_finish (self, res, &error)) {
+        g_dbus_method_invocation_take_error (ctx->invocation, error);
+        handle_hold_and_accept_context_free (ctx);
+        return;
+    }
+
+    for (l = ctx->active_calls; l; l = g_list_next (l))
+        mm_base_call_change_state (MM_BASE_CALL (l->data), MM_CALL_STATE_HELD, MM_CALL_STATE_REASON_UNKNOWN);
+    if (ctx->next_call)
+        mm_base_call_change_state (ctx->next_call, MM_CALL_STATE_ACTIVE, MM_CALL_STATE_REASON_ACCEPTED);
+
+    mm_gdbus_modem_voice_complete_hold_and_accept (ctx->skeleton, ctx->invocation);
+    handle_hold_and_accept_context_free (ctx);
+}
+
+static void
+prepare_hold_and_accept_foreach (MMBaseCall                 *call,
+                                 HandleHoldAndAcceptContext *ctx)
+{
+    switch (mm_base_call_get_state (call)) {
+    case MM_CALL_STATE_ACTIVE:
+        ctx->active_calls = g_list_append (ctx->active_calls, g_object_ref (call));
+        break;
+    case MM_CALL_STATE_WAITING:
+        g_clear_object (&ctx->next_call);
+        ctx->next_call = g_object_ref (call);
+        break;
+    case MM_CALL_STATE_HELD:
+        if (!ctx->next_call)
+            ctx->next_call = g_object_ref (call);
+        break;
+    default:
+        break;
+    }
+}
+
+static void
+handle_hold_and_accept_auth_ready (MMBaseModem                *self,
+                                   GAsyncResult               *res,
+                                   HandleHoldAndAcceptContext *ctx)
+{
+    MMModemState  modem_state = MM_MODEM_STATE_UNKNOWN;
+    GError       *error = NULL;
+    MMCallList   *list = NULL;
+
+    if (!mm_base_modem_authorize_finish (self, res, &error)) {
+        g_dbus_method_invocation_take_error (ctx->invocation, error);
+        handle_hold_and_accept_context_free (ctx);
+        return;
+    }
+
+    g_object_get (self,
+                  MM_IFACE_MODEM_STATE, &modem_state,
+                  NULL);
+
+    if (modem_state < MM_MODEM_STATE_ENABLED) {
+        g_dbus_method_invocation_return_error (ctx->invocation,
+                                               MM_CORE_ERROR,
+                                               MM_CORE_ERROR_WRONG_STATE,
+                                               "Cannot hold and accept: device not yet enabled");
+        handle_hold_and_accept_context_free (ctx);
+        return;
+    }
+
+    if (!MM_IFACE_MODEM_VOICE_GET_INTERFACE (self)->hold_and_accept ||
+        !MM_IFACE_MODEM_VOICE_GET_INTERFACE (self)->hold_and_accept_finish) {
+        g_dbus_method_invocation_return_error (ctx->invocation,
+                                               MM_CORE_ERROR,
+                                               MM_CORE_ERROR_UNSUPPORTED,
+                                               "Cannot hold and accept: unsupported");
+        handle_hold_and_accept_context_free (ctx);
+        return;
+    }
+
+    g_object_get (self,
+                  MM_IFACE_MODEM_VOICE_CALL_LIST, &list,
+                  NULL);
+    if (!list) {
+        g_dbus_method_invocation_return_error (ctx->invocation,
+                                               MM_CORE_ERROR,
+                                               MM_CORE_ERROR_WRONG_STATE,
+                                               "Cannot hold and accept: missing call list");
+        handle_hold_and_accept_context_free (ctx);
+        return;
+    }
+    mm_call_list_foreach (list, (MMCallListForeachFunc)prepare_hold_and_accept_foreach, ctx);
+    g_object_unref (list);
+
+    MM_IFACE_MODEM_VOICE_GET_INTERFACE (self)->hold_and_accept (MM_IFACE_MODEM_VOICE (self),
+                                                                (GAsyncReadyCallback)hold_and_accept_ready,
+                                                                ctx);
+}
+
+static gboolean
+handle_hold_and_accept (MmGdbusModemVoice     *skeleton,
+                        GDBusMethodInvocation *invocation,
+                        MMIfaceModemVoice     *self)
+{
+    HandleHoldAndAcceptContext *ctx;
+
+    ctx = g_slice_new0 (HandleHoldAndAcceptContext);
+    ctx->skeleton   = g_object_ref (skeleton);
+    ctx->invocation = g_object_ref (invocation);
+    ctx->self       = g_object_ref (self);
+
+    mm_base_modem_authorize (MM_BASE_MODEM (self),
+                             invocation,
+                             MM_AUTHORIZATION_VOICE,
+                             (GAsyncReadyCallback)handle_hold_and_accept_auth_ready,
+                             ctx);
+    return TRUE;
+}
+
+/*****************************************************************************/
+
 typedef struct {
     MmGdbusModemVoice     *skeleton;
     GDBusMethodInvocation *invocation;
@@ -1370,6 +1512,10 @@ interface_initialization_step (GTask *task)
                           "handle-hangup-and-accept",
                           G_CALLBACK (handle_hangup_and_accept),
                           self);
+        g_signal_connect (ctx->skeleton,
+                          "handle-hold-and-accept",
+                          G_CALLBACK (handle_hold_and_accept),
+                          self);
 
         /* Finally, export the new interface */
         mm_gdbus_object_skeleton_set_modem_voice (MM_GDBUS_OBJECT_SKELETON (self),
diff --git a/src/mm-iface-modem-voice.h b/src/mm-iface-modem-voice.h
index f65b63e0..d5395741 100644
--- a/src/mm-iface-modem-voice.h
+++ b/src/mm-iface-modem-voice.h
@@ -92,6 +92,14 @@ struct _MMIfaceModemVoice {
                                   MMCallDirection    direction,
                                   const gchar       *number);
 
+    /* Hold and accept */
+    void     (* hold_and_accept)        (MMIfaceModemVoice    *self,
+                                         GAsyncReadyCallback   callback,
+                                         gpointer              user_data);
+    gboolean (* hold_and_accept_finish) (MMIfaceModemVoice    *self,
+                                         GAsyncResult         *res,
+                                         GError              **error);
+
     /* Hangup and accept */
     void     (* hangup_and_accept)        (MMIfaceModemVoice    *self,
                                            GAsyncReadyCallback   callback,