Splitting GIS into a shared library, and a lot more

[aweather] / src / gis / gis-plugin.c

diff --git a/src/gis/gis-plugin.c b/src/gis/gis-plugin.c
new file mode 100644 (file)
index 0000000..e15c53c
--- /dev/null
+++ b/src/gis/gis-plugin.c
@@ -0,0 +1,147 @@
+/*
+ * Copyright (C) 2009 Andy Spencer <spenceal@rose-hulman.edu>
+ * 
+ * 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 3 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.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <glib.h>
+#include <gmodule.h>
+
+#include "gis-plugin.h"
+
+static void gis_plugin_base_init(gpointer g_class)
+{
+       static gboolean is_initialized = FALSE;
+       if (!is_initialized) {
+               /* add properties and signals to the interface here */
+               is_initialized = TRUE;
+       }
+}
+
+GType gis_plugin_get_type()
+{
+       static GType type = 0;
+       if (type == 0) {
+               static const GTypeInfo info = {
+                       sizeof(GisPluginInterface),
+                       gis_plugin_base_init,
+                       NULL,
+               };
+               type = g_type_register_static(G_TYPE_INTERFACE,
+                               "GisPlugin", &info, 0);
+       }
+       return type;
+}
+
+void gis_plugin_expose(GisPlugin *self)
+{
+       g_return_if_fail(GIS_IS_PLUGIN(self));
+       GIS_PLUGIN_GET_INTERFACE(self)->expose(self);
+}
+
+GtkWidget *gis_plugin_get_config(GisPlugin *self)
+{
+       g_return_val_if_fail(GIS_IS_PLUGIN(self), NULL);
+       return GIS_PLUGIN_GET_INTERFACE(self)->get_config(self);
+}
+
+/* Plugins API */
+typedef struct {
+       gchar *name;
+       GisPlugin *plugin;
+} GisPluginStore;
+
+GisPlugins *gis_plugins_new()
+{
+       return g_ptr_array_new();
+}
+
+void gis_plugins_free(GisPlugins *self)
+{
+       for (int i = 0; i < self->len; i++) {
+               GisPluginStore *store = g_ptr_array_index(self, i);
+               g_object_unref(store->plugin);
+               g_free(store->name);
+               g_free(store);
+               g_ptr_array_remove_index(self, i);
+       }
+       g_ptr_array_free(self, TRUE);
+}
+
+GList *gis_plugins_available()
+{
+       GDir *dir = g_dir_open(PLUGINDIR, 0, NULL);
+       GList *list = NULL;
+       const gchar *name;
+       while ((name = g_dir_read_name(dir))) {
+               if (g_pattern_match_simple("*.so", name)) {
+                       gchar **parts = g_strsplit(name, ".", 2);
+                       list = g_list_prepend(list, g_strdup(parts[0]));
+                       g_strfreev(parts);
+               }
+       }
+       return list;
+}
+
+GisPlugin *gis_plugins_load(GisPlugins *self, const char *name,
+               GisWorld *world, GisView *view, GisOpenGL *opengl, GisPrefs *prefs)
+{
+       gchar *path = g_strdup_printf("%s/%s.%s", PLUGINDIR, name, G_MODULE_SUFFIX);
+       GModule *module = g_module_open(path, 0);
+       g_free(path);
+       if (module == NULL) {
+               g_warning("Unable to load module %s: %s", name, g_module_error());
+               return NULL;
+       }
+
+       GisPluginConstructor constructor;
+       gchar *constructor_str = g_strconcat("gis_plugin_", name, "_new", NULL);
+       if (!g_module_symbol(module, constructor_str, (gpointer*)&constructor)) {
+               g_warning("Unable to load symbol %s from %s: %s",
+                               constructor_str, name, g_module_error());
+               g_module_close(module);
+               g_free(constructor_str);
+               return NULL;
+       }
+       g_free(constructor_str);
+
+       GisPluginStore *store = g_malloc(sizeof(GisPluginStore));
+       store->name = g_strdup(name);
+       store->plugin = constructor(world, view, opengl, prefs);
+       g_ptr_array_add(self, store);
+       return store->plugin;
+}
+
+gboolean gis_plugins_unload(GisPlugins *self, const char *name)
+{
+       for (int i = 0; i < self->len; i++) {
+               GisPluginStore *store = g_ptr_array_index(self, i);
+               if (g_str_equal(store->name, name)) {
+                       g_object_unref(store->plugin);
+                       g_free(store->name);
+                       g_free(store);
+                       g_ptr_array_remove_index(self, i);
+               }
+       }
+       return FALSE;
+}
+void gis_plugins_foreach(GisPlugins *self, GCallback _callback, gpointer user_data)
+{
+       typedef void (*CBFunc)(GisPlugin *, const gchar *, gpointer);
+       CBFunc callback = (CBFunc)_callback;
+       for (int i = 0; i < self->len; i++) {
+               GisPluginStore *store = g_ptr_array_index(self, i);
+               callback(store->plugin, store->name, user_data);
+       }
+}