core: implement a PropertiesChanged signal for the MMModem class

At the moment only the Enabled property is exported.

introspection/mm-modem.xml

@@ -1,6 +1,25 @@
 <?xml version="1.0" encoding="UTF-8" ?>
 
 <node name="/" xmlns:tp="http://telepathy.freedesktop.org/wiki/DbusSpec#extensions-v0">
+
+  <interface name="org.freedesktop.DBus.Properties">
+    <signal name="MmPropertiesChanged">
+      <tp:docstring>
+	One or more properties' values changed.
+      </tp:docstring>
+      <arg name="interface" type="s">
+	<tp:docstring>
+	  The D-Bus interface of the changed properties.
+	</tp:docstring>
+      </arg>
+      <arg name="properties" type="a{sv}">
+	<tp:docstring>
+	  The changed property names and their new values.
+	</tp:docstring>
+      </arg>
+    </signal>
+  </interface>
+
   <interface name="org.freedesktop.ModemManager.Modem">
     <method name="Enable">
       <tp:docstring>

marshallers/mm-marshal.list

@@ -4,4 +4,5 @@ VOID:OBJECT,UINT
 VOID:UINT,BOOLEAN
 VOID:UINT,UINT
 VOID:UINT,UINT,UINT
+VOID:STRING,BOXED
 

src/Makefile.am

@@ -49,7 +49,9 @@ modem_manager_SOURCES = \
 	mm-plugin.c \
 	mm-plugin.h \
 	mm-plugin-base.c \
-	mm-plugin-base.h
+	mm-plugin-base.h \
+	mm-properties-changed-signal.c \
+	mm-properties-changed-signal.h
 
 mm-manager-glue.h: $(top_srcdir)/introspection/mm-manager.xml
 	dbus-binding-tool --prefix=mm_manager --mode=glib-server --output=$@ $<

src/mm-modem-base.c

@@ -24,6 +24,7 @@
 #include "mm-serial-port.h"
 #include "mm-errors.h"
 #include "mm-options.h"
+#include "mm-properties-changed-signal.h"
 
 static void modem_init (MMModem *modem_class);
 
@@ -176,6 +177,10 @@ mm_modem_base_init (MMModemBase *self)
     MMModemBasePrivate *priv = MM_MODEM_BASE_GET_PRIVATE (self);
 
     priv->ports = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, g_object_unref);
+
+    mm_properties_changed_signal_register_property (G_OBJECT (self),
+                                                    MM_MODEM_ENABLED,
+                                                    MM_MODEM_DBUS_INTERFACE);
 }
 
 static void
@@ -183,15 +188,26 @@ modem_init (MMModem *modem_class)
 {
 }
 
+static gboolean
+is_enabled (MMModemState state)
+{
+    return (state >= MM_MODEM_STATE_ENABLED);
+}
+
 static void
 set_property (GObject *object, guint prop_id,
               const GValue *value, GParamSpec *pspec)
 {
     MMModemBasePrivate *priv = MM_MODEM_BASE_GET_PRIVATE (object);
+    gboolean old_enabled;
 
     switch (prop_id) {
     case MM_MODEM_PROP_STATE:
+        /* Ensure we update the 'enabled' property when the state changes */
+        old_enabled = is_enabled (priv->state);
         priv->state = g_value_get_uint (value);
+        if (old_enabled != is_enabled (priv->state))
+            g_object_notify (object, MM_MODEM_ENABLED);
         break;
     case MM_MODEM_PROP_DRIVER:
         /* Construct only */
@@ -250,7 +266,7 @@ get_property (GObject *object, guint prop_id,
         g_value_set_boolean (value, priv->valid);
         break;
     case MM_MODEM_PROP_ENABLED:
-        g_value_set_boolean (value, priv->state >= MM_MODEM_STATE_ENABLED);
+        g_value_set_boolean (value, is_enabled (priv->state));
         break;
     default:
         G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
@@ -319,5 +335,7 @@ mm_modem_base_class_init (MMModemBaseClass *klass)
     g_object_class_override_property (object_class,
                                       MM_MODEM_PROP_ENABLED,
                                       MM_MODEM_ENABLED);
+
+    mm_properties_changed_signal_new (object_class);
 }
 

src/mm-modem.h

@@ -47,6 +47,8 @@ typedef enum {
 #define MM_IS_MODEM(obj)   (G_TYPE_CHECK_INSTANCE_TYPE ((obj), MM_TYPE_MODEM))
 #define MM_MODEM_GET_INTERFACE(obj) (G_TYPE_INSTANCE_GET_INTERFACE ((obj), MM_TYPE_MODEM, MMModem))
 
+#define MM_MODEM_DBUS_INTERFACE "org.freedesktop.ModemManager.Modem"
+
 #define MM_MODEM_DATA_DEVICE   "device"
 #define MM_MODEM_MASTER_DEVICE "master-device"
 #define MM_MODEM_DRIVER        "driver"

src/mm-properties-changed-signal.c

@@ -0,0 +1,276 @@
+/* -*- 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) 2007 - 2008 Novell, Inc.
+ * Copyright (C) 2008 - 2009 Red Hat, Inc.
+ */
+
+#include <string.h>
+#include <stdio.h>
+
+#include <dbus/dbus-glib.h>
+#include "mm-marshal.h"
+#include "mm-properties-changed-signal.h"
+
+#define DBUS_TYPE_G_MAP_OF_VARIANT (dbus_g_type_get_map ("GHashTable", G_TYPE_STRING, G_TYPE_VALUE))
+
+#define PC_SIGNAL_NAME "mm-properties-changed"
+#define MM_DBUS_PROPERTY_CHANGED "MM_DBUS_PROPERTY_CHANGED"
+
+typedef struct {
+    /* Whitelist of GObject property names for which changes will be emitted
+     * over the bus.
+     *
+     * Mapping of {property-name -> dbus-interface}
+     */
+    GHashTable *registered;
+
+    /* Table of each D-Bus interface of the object for which one or more
+     * properties have changed, and those properties and their new values.
+     * Destroyed after the changed signal has been sent.
+     * 
+     * Mapping of {dbus-interface -> {property-name -> value}}
+     */
+    GHashTable *hash;
+
+    gulong signal_id;
+    guint idle_id;
+} PropertiesChangedInfo;
+
+static void
+destroy_value (gpointer data)
+{
+    GValue *val = (GValue *) data;
+
+    g_value_unset (val);
+    g_slice_free (GValue, val);
+}
+
+static PropertiesChangedInfo *
+properties_changed_info_new (void)
+{
+    PropertiesChangedInfo *info;
+
+    info = g_slice_new0 (PropertiesChangedInfo);
+
+    info->registered = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, g_free);
+    info->hash = g_hash_table_new_full (g_str_hash, g_str_equal, 
+                                        (GDestroyNotify) g_free,
+                                        (GDestroyNotify) g_hash_table_destroy);
+    return info;
+}
+
+static void
+properties_changed_info_destroy (gpointer data)
+{
+    PropertiesChangedInfo *info = (PropertiesChangedInfo *) data;
+
+    if (info->idle_id)
+        g_source_remove (info->idle_id);
+
+    g_hash_table_destroy (info->hash);
+    g_hash_table_destroy (info->registered);
+    g_slice_free (PropertiesChangedInfo, info);
+}
+
+#ifdef DEBUG
+static void
+add_to_string (gpointer key, gpointer value, gpointer user_data)
+{
+    char *buf = (char *) user_data;
+    GValue str_val = { 0, };
+
+    g_value_init (&str_val, G_TYPE_STRING);
+    if (!g_value_transform ((GValue *) value, &str_val)) {
+        if (G_VALUE_HOLDS_OBJECT (value)) {
+            GObject *obj = g_value_get_object (value);
+
+            if (g_value_get_object (value)) {
+                sprintf (buf + strlen (buf), "{%s: %p (%s)}, ",
+                         (const char *) key, obj, G_OBJECT_TYPE_NAME (obj));
+            } else {
+                sprintf (buf + strlen (buf), "{%s: %p}, ", (const char *) key, obj);
+            }
+        } else
+            sprintf (buf + strlen (buf), "{%s: <transform error>}, ", (const char *) key);
+    } else {
+        sprintf (buf + strlen (buf), "{%s: %s}, ", (const char *) key, g_value_get_string (&str_val));
+    }
+    g_value_unset (&str_val);
+}
+#endif
+
+static gboolean
+properties_changed (gpointer data)
+{
+    GObject *object = G_OBJECT (data);
+    PropertiesChangedInfo *info;
+    GHashTableIter iter;
+    gpointer key, value;
+
+    info = (PropertiesChangedInfo *) g_object_get_data (object, MM_DBUS_PROPERTY_CHANGED);
+    g_assert (info);
+
+    g_hash_table_iter_init (&iter, info->hash);
+    while (g_hash_table_iter_next (&iter, &key, &value)) {
+        const char *interface = (const char *) key;
+        GHashTable *props = (GHashTable *) value;
+
+#ifdef DEBUG
+        {
+            char buf[2048] = { 0, };
+            g_hash_table_foreach (props, add_to_string, &buf);
+            g_message ("%s: %s -> (%s) %s", __func__,
+                       G_OBJECT_TYPE_NAME (object),
+                       interface,
+                       buf);
+        }
+#endif
+
+        /* Send the PropertiesChanged signal */
+        g_signal_emit (object, info->signal_id, 0, interface, props);
+    }
+    g_hash_table_remove_all (info->hash);
+
+    return FALSE;
+}
+
+static void
+idle_id_reset (gpointer data)
+{
+    GObject *object = G_OBJECT (data);
+    PropertiesChangedInfo *info = (PropertiesChangedInfo *) g_object_get_data (object, MM_DBUS_PROPERTY_CHANGED);
+
+    /* info is unset when the object is being destroyed */
+    if (info)
+        info->idle_id = 0;
+}
+
+static char*
+uscore_to_wincaps (const char *uscore)
+{
+    const char *p;
+    GString *str;
+    gboolean last_was_uscore;
+
+    last_was_uscore = TRUE;
+  
+    str = g_string_new (NULL);
+    p = uscore;
+    while (p && *p) {
+        if (*p == '-' || *p == '_')
+            last_was_uscore = TRUE;
+        else {
+            if (last_was_uscore) {
+                g_string_append_c (str, g_ascii_toupper (*p));
+                last_was_uscore = FALSE;
+            } else
+                g_string_append_c (str, *p);
+        }
+        ++p;
+    }
+
+    return g_string_free (str, FALSE);
+}
+
+static PropertiesChangedInfo *
+get_properties_changed_info (GObject *object)
+{
+    PropertiesChangedInfo *info = NULL;
+
+    info = (PropertiesChangedInfo *) g_object_get_data (object, MM_DBUS_PROPERTY_CHANGED);
+    if (!info) {
+        info = properties_changed_info_new ();
+        g_object_set_data_full (object, MM_DBUS_PROPERTY_CHANGED, info, properties_changed_info_destroy);
+        info->signal_id = g_signal_lookup (PC_SIGNAL_NAME, G_OBJECT_TYPE (object));
+        g_assert (info->signal_id);
+    }
+
+    g_assert (info);
+    return info;
+}
+
+static void
+notify (GObject *object, GParamSpec *pspec)
+{
+    GHashTable *interfaces;
+    PropertiesChangedInfo *info;
+    const char *interface;
+    GValue *value;
+
+    info = get_properties_changed_info (object);
+
+    interface = g_hash_table_lookup (info->registered, pspec->name);
+    if (!interface)
+        return;
+
+    /* Check if there are other changed properties for this interface already,
+     * otherwise create a new hash table for all changed properties for this
+     * D-Bus interface.
+     */
+    interfaces = g_hash_table_lookup (info->hash, interface);
+    if (!interfaces) {
+        interfaces = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, destroy_value);
+        g_hash_table_insert (info->hash, g_strdup (interface), interfaces);
+    }
+
+    /* Now put the changed property value into the hash table of changed values
+     * for its D-Bus interface.
+     */
+    value = g_slice_new0 (GValue);
+    g_value_init (value, pspec->value_type);
+    g_object_get_property (object, pspec->name, value);
+    g_hash_table_insert (interfaces, uscore_to_wincaps (pspec->name), value);
+
+    if (!info->idle_id)
+        info->idle_id = g_idle_add_full (G_PRIORITY_DEFAULT_IDLE, properties_changed, object, idle_id_reset);
+}
+
+void
+mm_properties_changed_signal_register_property (GObject *object,
+                                                const char *property,
+                                                const char *interface)
+{
+    PropertiesChangedInfo *info;
+    const char *tmp;
+
+    /* All exported properties need to be registered explicitly for now since
+     * dbus-glib doesn't expose any method to find out the properties registered
+     * in the XML.
+     */
+
+    info = get_properties_changed_info (object);
+    tmp = g_hash_table_lookup (info->registered, property);
+    if (tmp) {
+        g_warning ("%s: property '%s' already registerd on interface '%s'",
+                   __func__, property, tmp);
+    } else
+        g_hash_table_insert (info->registered, g_strdup (property), g_strdup (interface));
+}
+
+guint
+mm_properties_changed_signal_new (GObjectClass *object_class)
+{
+    guint id;
+
+    object_class->notify = notify;
+
+    id = g_signal_new (PC_SIGNAL_NAME,
+                       G_OBJECT_CLASS_TYPE (object_class),
+                       G_SIGNAL_RUN_FIRST,
+                       0, NULL, NULL,
+                       mm_marshal_VOID__STRING_BOXED,
+                       G_TYPE_NONE, 2, G_TYPE_STRING, DBUS_TYPE_G_MAP_OF_VARIANT);
+
+    return id;
+}
+

src/mm-properties-changed-signal.h

@@ -0,0 +1,28 @@
+/* -*- 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) 2007 - 2008 Novell, Inc.
+ * Copyright (C) 2008 - 2009 Red Hat, Inc.
+ */
+
+#ifndef _MM_PROPERTIES_CHANGED_SIGNAL_H_
+#define _MM_PROPERTIES_CHANGED_SIGNAL_H_
+
+#include <glib-object.h>
+
+guint mm_properties_changed_signal_new (GObjectClass *object_class);
+
+void mm_properties_changed_signal_register_property (GObject *object,
+                                                     const char *property,
+                                                     const char *interface);
+
+#endif /* _MM_PROPERTIES_CHANGED_SIGNAL_H_ */