/*      $NetBSD: zero.c,v 1.1.1.2 2009/12/02 00:26:25 haad Exp $        */

/*
* Copyright (C) 2004-2007 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 "toolcontext.h"
#include "segtype.h"
#include "display.h"
#include "text_export.h"
#include "text_import.h"
#include "config.h"
#include "str_list.h"
#include "targets.h"
#include "lvm-string.h"
#include "activate.h"
#include "metadata.h"

static const char *_zero_name(const struct lv_segment *seg)
{
       return seg->segtype->name;
}

static int _zero_merge_segments(struct lv_segment *seg1, struct lv_segment *seg2)
{
       seg1->len += seg2->len;
       seg1->area_len += seg2->area_len;

       return 1;
}

#ifdef DEVMAPPER_SUPPORT
static int _zero_add_target_line(struct dev_manager *dm __attribute((unused)),
                                struct dm_pool *mem __attribute((unused)),
                                struct cmd_context *cmd __attribute((unused)),
                                void **target_state __attribute((unused)),
                                struct lv_segment *seg __attribute((unused)),
                                struct dm_tree_node *node,uint64_t len,
                                uint32_t *pvmove_mirror_count __attribute((unused)))
{
       return dm_tree_node_add_zero_target(node, len);
}

static int _zero_target_present(struct cmd_context *cmd,
                               const struct lv_segment *seg __attribute((unused)),
                               unsigned *attributes __attribute((unused)))
{
       static int _zero_checked = 0;
       static int _zero_present = 0;

       if (!_zero_checked)
               _zero_present = target_present(cmd, "zero", 1);

       _zero_checked = 1;

       return _zero_present;
}
#endif

static int _zero_modules_needed(struct dm_pool *mem,
                               const struct lv_segment *seg __attribute((unused)),
                               struct dm_list *modules)
{
       if (!str_list_add(mem, modules, "zero")) {
               log_error("zero module string list allocation failed");
               return 0;
       }

       return 1;
}

static void _zero_destroy(const struct segment_type *segtype)
{
       dm_free((void *) segtype);
}

static struct segtype_handler _zero_ops = {
       .name = _zero_name,
       .merge_segments = _zero_merge_segments,
#ifdef DEVMAPPER_SUPPORT
       .add_target_line = _zero_add_target_line,
       .target_present = _zero_target_present,
#endif
       .modules_needed = _zero_modules_needed,
       .destroy = _zero_destroy,
};

struct segment_type *init_zero_segtype(struct cmd_context *cmd)
{
       struct segment_type *segtype = dm_malloc(sizeof(*segtype));

       if (!segtype)
               return_NULL;

       segtype->cmd = cmd;
       segtype->ops = &_zero_ops;
       segtype->name = "zero";
       segtype->private = NULL;
       segtype->flags = SEG_CAN_SPLIT | SEG_VIRTUAL | SEG_CANNOT_BE_ZEROED;

       log_very_verbose("Initialised segtype: %s", segtype->name);

       return segtype;
}