/*      $NetBSD: sharedlib.c,v 1.1.1.2 2009/02/18 11:17:18 haad Exp $   */

/*
* Copyright (C) 2002-2004 Sistina Software, Inc. All rights reserved.
* Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
*
* This file is part of LVM2.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU Lesser General Public License v.2.1.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

#include "lib.h"
#include "config.h"
#include "lvm-string.h"
#include "sharedlib.h"
#include "toolcontext.h"

#include <limits.h>
#include <sys/stat.h>
#include <dlfcn.h>

void get_shared_library_path(struct cmd_context *cmd, const char *libname,
                            char *path, size_t path_len)
{
       struct stat info;
       const char *lib_dir;

       /* If libname doesn't begin with '/' then use lib_dir/libname,
        * if present */
       if (libname[0] == '/' ||
           !(lib_dir = find_config_tree_str(cmd, "global/library_dir", 0)) ||
           (dm_snprintf(path, path_len, "%s/%s", lib_dir,
                         libname) == -1) || stat(path, &info) == -1)
               strncpy(path, libname, path_len);
}

void *load_shared_library(struct cmd_context *cmd, const char *libname,
                         const char *desc, int silent)
{
       char path[PATH_MAX];
       void *library;

       if (is_static()) {
               log_error("Not loading shared %s library %s in static mode.",
                         desc, libname);
               return NULL;
       }

       get_shared_library_path(cmd, libname, path, sizeof(path));

       log_very_verbose("Opening shared %s library %s", desc, path);

       if (!(library = dlopen(path, RTLD_LAZY | RTLD_GLOBAL))) {
               if (silent && ignorelockingfailure())
                       log_verbose("Unable to open external %s library %s: %s",
                                   desc, path, dlerror());
               else
                       log_error("Unable to open external %s library %s: %s",
                                 desc, path, dlerror());
       }

       return library;
}