first public release of samba4 code

source/lib/module.c

@@ -0,0 +1,128 @@
+/* 
+   Unix SMB/CIFS implementation.
+   module loading system
+
+   Copyright (C) Jelmer Vernooij 2002
+   
+   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 2 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, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#include "includes.h"
+
+#ifdef HAVE_DLOPEN
+int smb_load_module(const char *module_name)
+{
+	void *handle;
+	init_module_function *init;
+	int status;
+	const char *error;
+
+	/* Always try to use LAZY symbol resolving; if the plugin has 
+	 * backwards compatibility, there might be symbols in the 
+	 * plugin referencing to old (removed) functions
+	 */
+	handle = sys_dlopen(module_name, RTLD_LAZY);
+
+	if(!handle) {
+		DEBUG(0, ("Error loading module '%s': %s\n", module_name, sys_dlerror()));
+		return False;
+	}
+
+	init = sys_dlsym(handle, "init_module");
+
+	/* we must check sys_dlerror() to determine if it worked, because
+           sys_dlsym() can validly return NULL */
+	error = sys_dlerror();
+	if (error) {
+		DEBUG(0, ("Error trying to resolve symbol 'init_module' in %s: %s\n", module_name, error));
+		return False;
+	}
+
+	status = init();
+
+	DEBUG(2, ("Module '%s' loaded\n", module_name));
+
+	return status;
+}
+
+/* Load all modules in list and return number of 
+ * modules that has been successfully loaded */
+int smb_load_modules(const char **modules)
+{
+	int i;
+	int success = 0;
+
+	for(i = 0; modules[i]; i++){
+		if(smb_load_module(modules[i])) {
+			success++;
+		}
+	}
+
+	DEBUG(2, ("%d modules successfully loaded\n", success));
+
+	return success;
+}
+
+int smb_probe_module(const char *subsystem, const char *module)
+{
+	char *full_path;
+	int rc;
+	TALLOC_CTX *mem_ctx;
+	
+	/* Check for absolute path */
+	if(module[0] == '/')return smb_load_module(module);
+	
+	mem_ctx = talloc_init("smb_probe_module");
+	if (!mem_ctx) {
+		DEBUG(0,("No memory for loading modules\n"));
+		return False;
+	}
+	full_path = talloc_strdup(mem_ctx, lib_path(mem_ctx, subsystem));
+	full_path = talloc_asprintf(mem_ctx, "%s/%s.%s", 
+		full_path, module, shlib_ext());
+	
+	rc = smb_load_module(full_path);
+	talloc_destroy(mem_ctx);
+	return rc;
+}
+
+#else /* HAVE_DLOPEN */
+
+int smb_load_module(const char *module_name)
+{
+	DEBUG(0,("This samba executable has not been built with plugin support"));
+	return False;
+}
+
+int smb_load_modules(const char **modules)
+{
+	DEBUG(0,("This samba executable has not been built with plugin support"));
+	return False;
+}
+
+int smb_probe_module(const char *subsystem, const char *module)
+{
+	DEBUG(0,("This samba executable has not been built with plugin support, not probing")); 
+	return False;
+}
+
+#endif /* HAVE_DLOPEN */
+
+void init_modules(void)
+{
+	if(lp_preload_modules()) 
+		smb_load_modules(lp_preload_modules());
+	/* FIXME: load static modules */
+}