[PATCH 03/15] core: introduced GrlCaps

[gemont igalia com]

From: Guillaume Emont <gemont igalia com>

The GrlCaps type will represent the capabilities of a given source for a given
operation.
---
 src/grl-caps.c |  134 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 src/grl-caps.h |   70 +++++++++++++++++++++++++++++
 2 files changed, 204 insertions(+), 0 deletions(-)
 create mode 100644 src/grl-caps.c
 create mode 100644 src/grl-caps.h

diff --git a/src/grl-caps.c b/src/grl-caps.c
new file mode 100644
index 0000000..c80a3e3
--- /dev/null
+++ b/src/grl-caps.c
@@ -0,0 +1,134 @@
+/*
+ * Copyright (C) 2011 Igalia S.L.
+ *
+ * Contact: Iago Toral Quiroga <itoral igalia com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation; version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ *
+ */
+
+/**
+ * SECTION:grl-caps
+ * @short_description: Describes the capabilities of a source for a given
+ * operation.
+ *
+ * A #GrlCaps instance is here to help you know if a given set of operation
+ * options is supported for a given operation.
+ *
+ * Here is an example of how this would be used.
+ * |[
+ * GrlCaps *caps = grl_metadata_source_get_caps (GRL_METADATA_SOURCE (my_source),
+                                                 GRL_OP_SEARCH);
+   GrlOperationOptions *supported_options;
+   if (grl_operation_options_obey_caps (my_options, caps, &supported_options, NULL))
+     grl_media_source_search (my_source, "blah", interesting_keys, my_options, ...);
+   else // only use a subset of the options we wanted to pass
+     grl_media_source_search (my_source, "blah", interesting_keys, supported_options, ...);
+ * ]|
+ *
+ * A #GrlCaps can also be passed to grl_operation_options_new(). The created
+ * #GrlOperationOptions instance would then check any change against its caps.
+ *
+ * @see_also: #GrlOperationOptions, grl_metadata_source_get_caps()
+ */
+#include <grl-caps.h>
+#include <grl-value-helper.h>
+
+#include "grl-operation-options-priv.h"
+
+#define GRL_CAPS_KEY_PAGINATION "pagination"
+#define GRL_CAPS_KEY_FLAGS "flags"
+
+G_DEFINE_TYPE (GrlCaps, grl_caps, G_TYPE_OBJECT);
+
+#define GRL_CAPS_GET_PRIVATE(o)\
+    (G_TYPE_INSTANCE_GET_PRIVATE ((o), GRL_CAPS_TYPE, GrlCapsPrivate))
+
+struct _GrlCapsPrivate {
+  GHashTable *data;
+};
+
+
+
+static void
+grl_caps_dispose (GrlCaps *self)
+{
+  G_OBJECT_CLASS (grl_caps_parent_class)->dispose ((GObject *) self);
+}
+
+static void
+grl_caps_finalize (GrlCaps *self)
+{
+  g_hash_table_unref (self->priv->data);
+  G_OBJECT_CLASS (grl_caps_parent_class)->finalize ((GObject *) self);
+}
+
+static void
+grl_caps_init (GrlCaps *self)
+{
+  self->priv = GRL_CAPS_GET_PRIVATE (self);
+
+  self->priv->data = grl_g_value_hashtable_new ();
+}
+
+static void
+grl_caps_class_init (GrlCapsClass *self_class)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (self_class);
+
+  g_type_class_add_private (self_class, sizeof (GrlCapsPrivate));
+  object_class->dispose = (void (*) (GObject *object)) grl_caps_dispose;
+  object_class->finalize = (void (*) (GObject *object)) grl_caps_finalize;
+}
+
+/* ========== API ========== */
+
+/**
+ * grl_caps_new:
+ *
+ * Creates a new caps object.
+ *
+ * Returns: a new caps object.
+ **/
+GrlCaps *
+grl_caps_new (void)
+{
+  return g_object_new (GRL_CAPS_TYPE, NULL);
+}
+
+/**
+ * grl_caps_test_option:
+ * @caps: a #GrlCaps instance
+ * @key: a key to test
+ * @value: the value corresponding to @key to test against @caps
+ *
+ * Checks whether (@key, @value) are authorized by @caps.
+ *
+ * Returns: %TRUE if (@key, @value) obey to @caps, %FALSE otherwise.
+ *
+ */
+gboolean
+grl_caps_test_option (GrlCaps *caps, const gchar *key, const GValue *value)
+{
+  if (0 == g_strcmp0 (key, GRL_OPERATION_OPTION_SKIP)
+      || 0 == g_strcmp0 (key, GRL_OPERATION_OPTION_COUNT)
+      || 0 == g_strcmp0 (key, GRL_OPERATION_OPTION_FLAGS))
+    /* these options must always be handled by plugins */
+    return TRUE;
+
+  return FALSE;
+}
+
diff --git a/src/grl-caps.h b/src/grl-caps.h
new file mode 100644
index 0000000..656c350
--- /dev/null
+++ b/src/grl-caps.h
@@ -0,0 +1,70 @@
+/*
+ * Copyright (C) 2011 Igalia S.L.
+ *
+ * Contact: Iago Toral Quiroga <itoral igalia com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation; version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ *
+ */
+
+#if !defined (_GRILO_H_INSIDE_) && !defined (GRILO_COMPILATION)
+#error "Only <grilo.h> can be included directly."
+#endif
+
+#if !defined (_GRL_CAPS_H_)
+#define _GRL_CAPS_H_
+
+#include <glib-object.h>
+#include <grl-definitions.h>
+
+G_BEGIN_DECLS
+
+typedef struct _GrlCapsPrivate GrlCapsPrivate;
+
+typedef struct {
+  GObject parent;
+
+  /*< private >*/
+  GrlCapsPrivate *priv;
+
+  gpointer _grl_reserved[GRL_PADDING_SMALL];
+} GrlCaps;
+
+typedef struct {
+  GObjectClass parent;
+
+  /*< private >*/
+  gpointer _grl_reserved[GRL_PADDING];
+} GrlCapsClass;
+
+#define GRL_CAPS_TYPE (grl_caps_get_type ())
+#define GRL_CAPS(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), GRL_CAPS_TYPE, GrlCaps))
+#define GRL_CAPS_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), GRL_CAPS_TYPE, GrlCapsClass))
+#define IS_GRL_CAPS(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GRL_CAPS_TYPE))
+#define IS_GRL_CAPS_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), GRL_CAPS_TYPE))
+#define GRL_CAPS_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), GRL_CAPS_TYPE, GrlCapsClass))
+
+GType grl_caps_get_type (void);
+
+GrlCaps *grl_caps_new (void);
+
+gboolean grl_caps_test_option (GrlCaps *caps,
+                               const gchar *key,
+                               const GValue *value);
+
+G_END_DECLS
+
+#endif /* _GRL_CAPS_H_ */
-- 
1.7.5.4