1 files changed, 84 insertions, 0 deletions
diff --git a/openbox/engine.c b/openbox/engine.c
new file mode 100644
index 00000000..3457da18
--- /dev/null
+++ b/openbox/engine.c
@@ -0,0 +1,84 @@
+#include "engine.h"
+
+#include <glib.h>
+#include <gmodule.h>
+#ifdef HAVE_STDLIB_H
+#  include <stdlib.h>
+#endif
+
+static GModule *module;
+static EngineStartup *estartup;
+static EngineShutdown *eshutdown;
+
+#define LOADSYM(name, var) \
+    if (!g_module_symbol(module, #name, (gpointer*)&var)) { \
+        g_warning("Failed to load symbol %s from engine", #name); \
+        return FALSE; \
+    }
+
+static gboolean load(char *name)
+{
+    char *path;
+
+    g_assert(module == NULL);
+
+    path = g_build_filename(ENGINEDIR, name, NULL);
+    module = g_module_open(path, G_MODULE_BIND_LAZY);
+    g_free(path);
+
+    if (module == NULL) {
+	path = g_build_filename(g_get_home_dir(), ".openbox", "engines", name,
+				NULL);
+	module = g_module_open(path, G_MODULE_BIND_LAZY);
+	g_free(path);
+    }
+
+    if (module == NULL)
+	return FALSE;
+
+    /* load the engine's symbols */
+    LOADSYM(startup, estartup);
+    LOADSYM(shutdown, eshutdown);
+    LOADSYM(frame_new, engine_frame_new);
+    LOADSYM(frame_grab_client, engine_frame_grab_client);
+    LOADSYM(frame_release_client, engine_frame_release_client);
+    LOADSYM(frame_adjust_size, engine_frame_adjust_size);
+    LOADSYM(frame_adjust_position, engine_frame_adjust_position);
+    LOADSYM(frame_adjust_shape, engine_frame_adjust_shape);
+    LOADSYM(frame_adjust_state, engine_frame_adjust_state);
+    LOADSYM(frame_adjust_focus, engine_frame_adjust_focus);
+    LOADSYM(frame_adjust_title, engine_frame_adjust_title);
+    LOADSYM(frame_adjust_icon, engine_frame_adjust_icon);
+    LOADSYM(frame_show, engine_frame_show);
+    LOADSYM(frame_hide, engine_frame_hide);
+    LOADSYM(get_context, engine_get_context);
+
+    if (!estartup())
+	return FALSE;
+
+    return TRUE;
+}
+
+void engine_startup(char *engine)
+{
+    module = NULL;
+
+    if (engine != NULL) {
+	if (load(engine))
+	    return;
+	g_warning("Failed to load the engine '%s'", engine);
+	g_message("Falling back to the default: '%s'", DEFAULT_ENGINE);
+    }
+    if (!load(DEFAULT_ENGINE)) {
+	g_critical("Failed to load the engine '%s'. Aborting", DEFAULT_ENGINE);
+	exit(1);
+    }
+}
+
+void engine_shutdown()
+{
+    if (module != NULL) {
+	eshutdown();
+	g_module_close(module);
+    }
+}