Merge remote branch 'origin/master' into dexela

Conflicts:
	CMakeLists.txt
	src/CMakeLists.txt
	src/uca-camera.c

1 files changed, 345 insertions, 0 deletions

diff --git a/src/uca-plugin-manager.c b/src/uca-plugin-manager.c
new file mode 100644
index 0000000..e99f478
--- /dev/null
+++ b/src/uca-plugin-manager.c
@@ -0,0 +1,345 @@
+/* Copyright (C) 2012 Matthias Vogelgesang <matthias.vogelgesang@kit.edu>
+   (Karlsruhe Institute of Technology)
+
+   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; either 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, USA */
+
+/**
+ * SECTION:uca-plugin-manager
+ * @Short_description: Load an #UcaFilter from a shared object
+ * @Title: UcaPluginManager
+ *
+ * The plugin manager opens shared object modules searched for in locations
+ * specified with uca_plugin_manager_add_path(). A #UcaCamera can be
+ * instantiated with uca_plugin_manager_new_camera() with a one-to-one mapping
+ * between filter name xyz and module name libucaxyz.so. Any errors are reported
+ * as one of #UcaPluginManagerError codes. To get a list of available camera
+ * names call uca_plugin_manager_get_available_cameras().
+ *
+ * By default, any path listed in the %UCA_CAMERA_PATH environment variable is
+ * added to the search path.
+ *
+ * @Since: 1.1
+ */
+#include <gmodule.h>
+#include "uca-plugin-manager.h"
+
+G_DEFINE_TYPE (UcaPluginManager, uca_plugin_manager, G_TYPE_OBJECT)
+
+#define UCA_PLUGIN_MANAGER_GET_PRIVATE(obj) (G_TYPE_INSTANCE_GET_PRIVATE((obj), UCA_TYPE_PLUGIN_MANAGER, UcaPluginManagerPrivate))
+
+struct _UcaPluginManagerPrivate {
+    GList *search_paths;
+};
+
+static const gchar *MODULE_PATTERN = "libuca([A-Za-z]+)";
+
+typedef UcaCamera * (*GetCameraFunc) (GError **error);
+
+/**
+ * UcaPluginManagerError:
+ * @UCA_PLUGIN_MANAGER_ERROR_MODULE_NOT_FOUND: The module could not be found
+ * @UCA_PLUGIN_MANAGER_ERROR_MODULE_OPEN: Module could not be opened
+ * @UCA_PLUGIN_MANAGER_ERROR_SYMBOL_NOT_FOUND: Necessary entry symbol was not
+ *      found
+ *
+ * Possible errors that uca_plugin_manager_get_filter() can return.
+ */
+GQuark
+uca_plugin_manager_error_quark (void)
+{
+    return g_quark_from_static_string ("uca-plugin-manager-error-quark");
+}
+
+/**
+ * uca_plugin_manager_new:
+ *
+ * Create a plugin manager object to instantiate camera objects.
+ *
+ * Return value: A new plugin manager object.
+ */
+UcaPluginManager *
+uca_plugin_manager_new ()
+{
+    return UCA_PLUGIN_MANAGER (g_object_new (UCA_TYPE_PLUGIN_MANAGER, NULL));
+}
+
+/**
+ * uca_plugin_manager_add_path:
+ * @manager: A #UcaPluginManager
+ * @path: Path to look for camera modules
+ *
+ * Add a search path to the plugin manager.
+ */
+void
+uca_plugin_manager_add_path (UcaPluginManager   *manager,
+                             const gchar        *path)
+{
+    g_return_if_fail (UCA_IS_PLUGIN_MANAGER (manager));
+
+    if (g_file_test (path, G_FILE_TEST_EXISTS | G_FILE_TEST_IS_DIR)) {
+        UcaPluginManagerPrivate *priv;
+
+        priv = manager->priv;
+        priv->search_paths = g_list_append (priv->search_paths,
+                                            g_strdup (path));
+    }
+}
+
+static GList *
+get_camera_module_paths (const gchar *path)
+{
+    GRegex *pattern;
+    GDir *dir;
+    GList *result = NULL;
+
+    pattern = g_regex_new (MODULE_PATTERN, 0, 0, NULL);
+    dir = g_dir_open (path, 0, NULL);
+
+    if (dir != NULL) {
+        GMatchInfo *match_info = NULL;
+        const gchar *name = g_dir_read_name (dir);
+
+        while (name != NULL) {
+            if (g_regex_match (pattern, name, 0, &match_info))
+                result = g_list_append (result, g_build_filename (path, name, NULL));
+
+            g_match_info_free (match_info);
+            name = g_dir_read_name (dir);
+        }
+    }
+
+    return result;
+}
+
+static GList *
+scan_search_paths (GList *search_paths)
+{
+    GList *camera_paths = NULL;
+
+    for (GList *it = g_list_first (search_paths); it != NULL; it = g_list_next (it)) {
+        camera_paths = g_list_concat (camera_paths,
+                                      get_camera_module_paths ((const gchar*) it->data));
+    }
+
+    return camera_paths;
+}
+
+static void
+transform_camera_module_path_to_name (gchar *path, GList **result)
+{
+    GRegex *pattern;
+    GMatchInfo *match_info;
+
+    pattern = g_regex_new (MODULE_PATTERN, 0, 0, NULL);
+    g_regex_match (pattern, path, 0, &match_info);
+
+    *result = g_list_append (*result, g_match_info_fetch (match_info, 1));
+    g_match_info_free (match_info);
+}
+
+static void
+list_free_full (GList *list)
+{
+    g_list_foreach (list, (GFunc) g_free, NULL);
+    g_list_free (list);
+}
+
+/**
+ * uca_plugin_manager_get_available_cameras:
+ * @manager: A #UcaPluginManager
+ *
+ * Return value: (element-type utf8) (transfer full): A list with strings of
+ * available camera names. You have to free the individual strings with
+ * g_list_foreach(list, (GFunc) g_free, NULL) and the list itself with
+ * g_list_free.
+ */
+GList *
+uca_plugin_manager_get_available_cameras (UcaPluginManager *manager)
+{
+    UcaPluginManagerPrivate *priv;
+    GList *camera_paths;
+    GList *camera_names = NULL;
+
+    g_return_val_if_fail (UCA_IS_PLUGIN_MANAGER (manager), NULL);
+
+    priv = manager->priv;
+    camera_paths = scan_search_paths (priv->search_paths);
+
+    g_list_foreach (camera_paths, (GFunc) transform_camera_module_path_to_name, &camera_names);
+    list_free_full (camera_paths);
+
+    return camera_names;
+}
+
+static gchar *
+find_camera_module_path (GList *search_paths, const gchar *name)
+{
+    gchar *result = NULL;
+    GList *paths;
+
+    paths = scan_search_paths (search_paths);
+
+    for (GList *it = g_list_first (paths); it != NULL; it = g_list_next (it)) {
+        gchar *path = (gchar *) it->data;
+        gchar *basename = g_path_get_basename ((gchar *) path);
+
+        if (g_strrstr (basename, name)) {
+            result = g_strdup (path);
+            g_free (basename);
+            break;
+        }
+
+        g_free (basename);
+    }
+
+    list_free_full (paths);
+    return result;
+}
+
+/**
+ * uca_plugin_manager_get_camera:
+ * @manager: A #UcaPluginManager
+ * @name: Name of the camera module, that maps to libuca<name>.so
+ * @error: Location for a #GError
+ *
+ * Create a new camera instance with camera @name.
+ *
+ * Returns: (transfer full): A new #UcaCamera object.
+ */
+UcaCamera *
+uca_plugin_manager_get_camera (UcaPluginManager   *manager,
+                               const gchar        *name,
+                               GError            **error)
+{
+    UcaPluginManagerPrivate *priv;
+    UcaCamera *camera;
+    GModule *module;
+    GetCameraFunc *func;
+    gchar *module_path;
+    GError *tmp_error = NULL;
+
+    const gchar *symbol_name = "uca_camera_impl_new";
+
+    g_return_val_if_fail (UCA_IS_PLUGIN_MANAGER (manager) && (name != NULL), NULL);
+
+    priv = manager->priv;
+    module_path = find_camera_module_path (priv->search_paths, name);
+
+    if (module_path == NULL) {
+        g_set_error (error, UCA_PLUGIN_MANAGER_ERROR, UCA_PLUGIN_MANAGER_ERROR_MODULE_NOT_FOUND,
+                "Camera module `%s' not found", name);
+        return NULL;
+    }
+
+    module = g_module_open (module_path, G_MODULE_BIND_LAZY);
+    g_free (module_path);
+
+    if (!module) {
+        g_set_error (error, UCA_PLUGIN_MANAGER_ERROR, UCA_PLUGIN_MANAGER_ERROR_MODULE_OPEN,
+                     "Camera module `%s' could not be opened: %s", name, g_module_error ());
+        return NULL;
+    }
+
+    func = g_malloc0 (sizeof (GetCameraFunc));
+
+    if (!g_module_symbol (module, symbol_name, (gpointer *) func)) {
+        g_set_error (error, UCA_PLUGIN_MANAGER_ERROR, UCA_PLUGIN_MANAGER_ERROR_SYMBOL_NOT_FOUND,
+                     "%s", g_module_error ());
+        g_free (func);
+
+        if (!g_module_close (module))
+            g_warning ("%s", g_module_error ());
+
+        return NULL;
+    }
+
+    camera = (*func) (&tmp_error);
+
+    if (tmp_error != NULL) {
+        g_propagate_error (error, tmp_error);
+        return NULL;
+    }
+
+    return camera;
+}
+
+static void
+uca_plugin_manager_get_property (GObject *object, guint property_id, GValue *value, GParamSpec *pspec)
+{
+    switch (property_id) {
+        default:
+            G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
+            break;
+    }
+}
+
+static void
+uca_plugin_manager_set_property (GObject *object, guint property_id, const GValue *value, GParamSpec *pspec)
+{
+    switch (property_id) {
+        default:
+            G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
+            break;
+    }
+}
+
+static void
+uca_plugin_manager_dispose (GObject *object)
+{
+    G_OBJECT_CLASS (uca_plugin_manager_parent_class)->dispose (object);
+}
+
+static void
+uca_plugin_manager_finalize (GObject *object)
+{
+    UcaPluginManagerPrivate *priv = UCA_PLUGIN_MANAGER_GET_PRIVATE (object);
+
+    g_list_foreach (priv->search_paths, (GFunc) g_free, NULL);
+    g_list_free (priv->search_paths);
+
+    G_OBJECT_CLASS (uca_plugin_manager_parent_class)->finalize (object);
+}
+
+static void
+uca_plugin_manager_class_init (UcaPluginManagerClass *klass)
+{
+    GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
+    gobject_class->get_property = uca_plugin_manager_get_property;
+    gobject_class->set_property = uca_plugin_manager_set_property;
+    gobject_class->dispose      = uca_plugin_manager_dispose;
+    gobject_class->finalize     = uca_plugin_manager_finalize;
+
+    g_type_class_add_private (klass, sizeof (UcaPluginManagerPrivate));
+}
+
+static void
+uca_plugin_manager_init (UcaPluginManager *manager)
+{
+    UcaPluginManagerPrivate *priv;
+    const gchar *uca_camera_path;
+
+    manager->priv = priv = UCA_PLUGIN_MANAGER_GET_PRIVATE (manager);
+    priv->search_paths = NULL;
+
+    uca_camera_path = g_getenv ("UCA_CAMERA_PATH");
+
+    if (uca_camera_path != NULL)
+        uca_plugin_manager_add_path (manager, uca_camera_path);
+
+    uca_plugin_manager_add_path (manager, "/usr/lib/uca");
+    uca_plugin_manager_add_path (manager, "/usr/lib64/uca");
+    uca_plugin_manager_add_path (manager, "/usr/local/lib/uca");
+    uca_plugin_manager_add_path (manager, "/usr/local/lib64/uca");
+}