LIBGLADE_MODULE_PATH

[jacob berkman <jacob ximian com>]

hi,

this patch lets libglade search a path for its modules.  this allows
people w/o write access to /usr install their own glade modules in their
home directory, among other things.

this basically steals the gtk module finding code.

i'd like to see a function in gmodule which does this for one shared env
var (G_MODULE_PATH) such that each library doesn't need to implement it,
but i assume it's too late to get this into 2.0.  if so, i'll do a patch
for gmodule 2.2.

anyway, does this look ok to commit?

jacob
-- 
"Beat mixing is 10000 times more fun than even video games."
	-- bt

Index: glade-init.c
===================================================================
RCS file: /cvs/gnome/libglade/glade/glade-init.c,v
retrieving revision 1.16
diff -u -r1.16 glade-init.c
--- glade-init.c	2001/10/31 04:10:03	1.16
+++ glade-init.c	2001/11/05 22:36:43
@@ -27,6 +27,8 @@
 #include <glib.h>
 #include <gmodule.h>
 
+#include <pango/pango-utils.h>
+
 #include "glade-init.h"
 #include "glade-build.h"
 
@@ -61,6 +63,84 @@
 
 static GPtrArray *loaded_packages = NULL;
 
+static gchar **
+get_module_path (void)
+{
+    const gchar *module_path_env = g_getenv ("LIBGLADE_MODULE_PATH");
+    const gchar *exe_prefix = g_getenv("LIBGLADE_EXE_PREFIX");
+    gchar **result;
+    gchar *module_path;
+    gchar *default_dir;
+    
+    if (exe_prefix)
+	default_dir = g_build_filename (exe_prefix, "lib", NULL);
+    else
+	default_dir = g_strdup (GLADE_LIBDIR);
+    
+    module_path = g_strconcat (module_path_env ? module_path_env : "",
+			       module_path_env ? G_SEARCHPATH_SEPARATOR_S : "",
+			       default_dir, NULL);
+    
+    result = pango_split_file_list (module_path);
+    
+    g_free (default_dir);
+    g_free (module_path);
+    
+    return result;
+}
+
+static GModule *
+find_module (gchar      **module_path,
+	     const gchar *subdir,
+	     const gchar *name)
+{
+    GModule *module;
+    gchar *module_name;
+    gint i;
+    
+    if (g_path_is_absolute (name))
+	return g_module_open (name, G_MODULE_BIND_LAZY);
+    
+    for (i = 0; module_path[i]; i++) {
+	gchar *version_directory;
+	
+#ifndef G_OS_WIN32 /* ignoring GTK_BINARY_VERSION elsewhere too */
+	version_directory = g_build_filename (module_path[i], subdir, NULL);
+	module_name = g_module_build_path (version_directory, name);
+	g_free (version_directory);
+	
+	/*g_print ("trying: %s\n", module_name);*/
+
+	if (g_file_test (module_name, G_FILE_TEST_EXISTS)) {
+	    module = g_module_open (module_name, G_MODULE_BIND_LAZY);
+	    g_free (module_name);
+	    return module;
+	}
+      
+	g_free (module_name);
+#endif
+	
+	module_name = g_module_build_path (module_path[i], name);
+	
+	if (g_file_test (module_name, G_FILE_TEST_EXISTS)) {
+	    module = g_module_open (module_name, G_MODULE_BIND_LAZY);
+	    g_free (module_name);
+	    return module;
+	}
+	
+	g_free (module_name);
+    }
+    
+    /* As last resort, try loading without an absolute path (using system
+     * library path)
+     */
+    module_name = g_module_build_path (NULL, name);
+    module = g_module_open (module_name, G_MODULE_BIND_LAZY);
+    g_free(module_name);
+    
+    return module;
+}
+
 /**
  * glade_require:
  * @library: the required library
@@ -74,9 +154,9 @@
 glade_require(const gchar *library)
 {
     gboolean already_loaded = FALSE;
-    gchar *filename;
     GModule *module;
     void (* init_func)(void);
+    static char **module_path = NULL;
 
     /* a call to glade_init here to make sure libglade is initialised */
     glade_init();
@@ -93,16 +173,17 @@
 
     if (already_loaded)
 	return;
+
+    if (!module_path)
+	module_path = get_module_path ();
+
+    module = find_module (module_path, "libglade/2.0", library);
 
-    filename = g_module_build_path (GLADE_MODULE_DIR, library);
-    module = g_module_open(filename, G_MODULE_BIND_LAZY);
     if (!module) {
 	g_warning("Could not load support for `%s': %s", library,
 		  g_module_error());
-	g_free(filename);
 	return;
     }
-    g_free(filename);
 
     if (!g_module_symbol(module, "glade_module_register_widgets",
 			 (gpointer)&init_func)) {