src/plugin.c

   1 /* plugin.c -- generic plugin routines for vlock,
   2  *             the VT locking program for linux
   3  *
   4  * This program is copyright (C) 2007 Frank Benkstein, and is free
   5  * software which is freely distributable under the terms of the
   6  * GNU General Public License version 2, included as the file COPYING in this
   7  * distribution.  It is NOT public domain software, and any
   8  * redistribution not permitted by the GNU General Public License is
   9  * expressly forbidden without prior written permission from
  10  * the author.
  11  *
  12  */
  13
  14 #include <stdlib.h>
  15 #include <string.h>
  16 #include <errno.h>
  17
  18 #include <glib.h>
  19
  20 #include "plugin.h"
  21 #include "util.h"
  22
  23 GQuark vlock_plugin_error_quark(void)
  24 {
  25   return g_quark_from_static_string("vlock-plugin-error-quark");
  26 }
  27
  28 G_DEFINE_TYPE(VlockPlugin, vlock_plugin, G_TYPE_OBJECT)
  29
  30 /* Initialize plugin to default values. */
  31 static void vlock_plugin_init(VlockPlugin *self)
  32 {
  33   self->name = NULL;
  34 }
  35
  36 /* Create new plugin object. */
  37 static GObject *vlock_plugin_constructor(
  38     GType gtype,
  39     guint n_properties,
  40     GObjectConstructParam *properties)
  41 {
  42   GObjectClass *parent_class = G_OBJECT_CLASS(vlock_plugin_parent_class);
  43   GObject *object = parent_class->constructor(gtype, n_properties, properties);
  44   VlockPlugin *self = VLOCK_PLUGIN(object);
  45
  46   g_return_val_if_fail(self->name != NULL, NULL);
  47
  48   return object;
  49 }
  50
  51 /* Destroy plugin object. */
  52 static void vlock_plugin_finalize(GObject *object)
  53 {
  54   VlockPlugin *self = VLOCK_PLUGIN(object);
  55
  56   g_free(self->name);
  57   self->name = NULL;
  58
  59   /* Destroy dependency lists. */
  60   for (size_t i = 0; i < nr_dependencies; i++) {
  61     while (self->dependencies[i] != NULL) {
  62       g_free(self->dependencies[i]->data);
  63       self->dependencies[i] = g_list_delete_link(self->dependencies[i], self->dependencies[i]);
  64     }
  65   }
  66
  67   G_OBJECT_CLASS(vlock_plugin_parent_class)->finalize(object);
  68 }
  69
  70 /* Properties. */
  71 enum {
  72   PROP_VLOCK_PLUGIN_0,
  73   PROP_VLOCK_PLUGIN_NAME
  74 };
  75
  76 static void vlock_plugin_set_name(VlockPlugin *self, const gchar *name)
  77 {
  78   /* For security plugin names must not contain a slash. */
  79   char *last_slash = strrchr(name, '/');
  80
  81   if (last_slash != NULL)
  82     name = last_slash+1;
  83
  84   self->name = g_strdup(name);
  85 }
  86
  87 /* Set properties. */
  88 static void vlock_plugin_set_property(
  89     GObject *object,
  90     guint property_id,
  91     const GValue *value,
  92     GParamSpec *pspec)
  93 {
  94   VlockPlugin *self = VLOCK_PLUGIN(object);
  95
  96   switch (property_id)
  97   {
  98     case PROP_VLOCK_PLUGIN_NAME:
  99       g_free(self->name);
 100       vlock_plugin_set_name(self, g_value_get_string(value));
 101       break;
 102     default:
 103       G_OBJECT_WARN_INVALID_PROPERTY_ID(object, property_id, pspec);
 104       break;
 105   }
 106 }
 107
 108 /* Get properties. */
 109 static void vlock_plugin_get_property(
 110     GObject *object,
 111     guint property_id,
 112     GValue *value,
 113     GParamSpec *pspec)
 114 {
 115   VlockPlugin *self = VLOCK_PLUGIN(object);
 116
 117   switch (property_id)
 118   {
 119     case PROP_VLOCK_PLUGIN_NAME:
 120       g_value_set_string(value, self->name);
 121       break;
 122     default:
 123       G_OBJECT_WARN_INVALID_PROPERTY_ID(object, property_id, pspec);
 124       break;
 125   }
 126 }
 127
 128 /* Initialize plugin class. */
 129 static void vlock_plugin_class_init(VlockPluginClass *klass)
 130 {
 131   GObjectClass *gobject_class = G_OBJECT_CLASS(klass);
 132   GParamSpec *vlock_plugin_param_spec;
 133
 134   /* Virtual methods. */
 135   klass->open = NULL;
 136   klass->call_hook = NULL;
 137
 138   /* Install overridden methods. */
 139   gobject_class->constructor = vlock_plugin_constructor;
 140   gobject_class->finalize = vlock_plugin_finalize;
 141   gobject_class->set_property = vlock_plugin_set_property;
 142   gobject_class->get_property = vlock_plugin_get_property;
 143
 144   /* Install properties. */
 145   vlock_plugin_param_spec = g_param_spec_string(
 146       "name",
 147       "plugin name",
 148       "Set the plugin's name",
 149       NULL,
 150       G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE
 151   );
 152
 153   g_object_class_install_property(
 154       gobject_class,
 155       PROP_VLOCK_PLUGIN_NAME,
 156       vlock_plugin_param_spec
 157   );
 158 }
 159
 160 bool vlock_plugin_open(VlockPlugin *self, GError **error)
 161 {
 162   VlockPluginClass *klass = VLOCK_PLUGIN_GET_CLASS(self);
 163   g_assert(klass->open != NULL);
 164   return klass->open(self, error);
 165 }
 166
 167 bool vlock_plugin_call_hook(VlockPlugin *self, const gchar *hook_name)
 168 {
 169   VlockPluginClass *klass = VLOCK_PLUGIN_GET_CLASS(self);
 170   g_assert(klass->call_hook != NULL);
 171   return klass->call_hook(self, hook_name);
 172 }