/* vi: set sw=4 ts=4: */
/*
 * badblocks.c --- routines to manipulate the bad block structure
 *
 * Copyright (C) 1994, 1995, 1996 Theodore Ts'o.
 *
 * %Begin-Header%
 * This file may be redistributed under the terms of the GNU Public
 * License.
 * %End-Header%
 */

#include <stdio.h>
#include <string.h>
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <fcntl.h>
#include <time.h>
#if HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#if HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif

#include "ext2_fs.h"
#include "ext2fsP.h"

/*
 * Helper function for making a badblocks list
 */
static errcode_t make_u32_list(int size, int num, __u32 *list,
                               ext2_u32_list *ret)
{
        ext2_u32_list   bb;
        errcode_t       retval;

        retval = ext2fs_get_mem(sizeof(struct ext2_struct_u32_list), &bb);
        if (retval)
                return retval;
        memset(bb, 0, sizeof(struct ext2_struct_u32_list));
        bb->magic = EXT2_ET_MAGIC_BADBLOCKS_LIST;
        bb->size = size ? size : 10;
        bb->num = num;
        retval = ext2fs_get_mem(bb->size * sizeof(blk_t), &bb->list);
        if (!bb->list) {
                ext2fs_free_mem(&bb);
                return retval;
        }
        if (list)
                memcpy(bb->list, list, bb->size * sizeof(blk_t));
        else
                memset(bb->list, 0, bb->size * sizeof(blk_t));
        *ret = bb;
        return 0;
}


/*
 * This procedure creates an empty u32 list.
 */
errcode_t ext2fs_u32_list_create(ext2_u32_list *ret, int size)
{
        return make_u32_list(size, 0, 0, ret);
}

/*
 * This procedure creates an empty badblocks list.
 */
errcode_t ext2fs_badblocks_list_create(ext2_badblocks_list *ret, int size)
{
        return make_u32_list(size, 0, 0, (ext2_badblocks_list *) ret);
}


/*
 * This procedure copies a badblocks list
 */
errcode_t ext2fs_u32_copy(ext2_u32_list src, ext2_u32_list *dest)
{
        errcode_t       retval;

        retval = make_u32_list(src->size, src->num, src->list, dest);
        if (retval)
                return retval;
        (*dest)->badblocks_flags = src->badblocks_flags;
        return 0;
}

errcode_t ext2fs_badblocks_copy(ext2_badblocks_list src,
                                ext2_badblocks_list *dest)
{
        return ext2fs_u32_copy((ext2_u32_list) src,
                               (ext2_u32_list *) dest);
}

/*
 * This procedure frees a badblocks list.
 *
 * (note: moved to closefs.c)
 */


/*
 * This procedure adds a block to a badblocks list.
 */
errcode_t ext2fs_u32_list_add(ext2_u32_list bb, __u32 blk)
{
        errcode_t       retval;
        int             i, j;
        unsigned long   old_size;

        EXT2_CHECK_MAGIC(bb, EXT2_ET_MAGIC_BADBLOCKS_LIST);

        if (bb->num >= bb->size) {
                old_size = bb->size * sizeof(__u32);
                bb->size += 100;
                retval = ext2fs_resize_mem(old_size, bb->size * sizeof(__u32),
                                           &bb->list);
                if (retval) {
                        bb->size -= 100;
                        return retval;
                }
        }

        /*
         * Add special case code for appending to the end of the list
         */
        i = bb->num-1;
        if ((bb->num != 0) && (bb->list[i] == blk))
                return 0;
        if ((bb->num == 0) || (bb->list[i] < blk)) {
                bb->list[bb->num++] = blk;
                return 0;
        }

        j = bb->num;
        for (i=0; i < bb->num; i++) {
                if (bb->list[i] == blk)
                        return 0;
                if (bb->list[i] > blk) {
                        j = i;
                        break;
                }
        }
        for (i=bb->num; i > j; i--)
                bb->list[i] = bb->list[i-1];
        bb->list[j] = blk;
        bb->num++;
        return 0;
}

errcode_t ext2fs_badblocks_list_add(ext2_badblocks_list bb, blk_t blk)
{
        return ext2fs_u32_list_add((ext2_u32_list) bb, (__u32) blk);
}

/*
 * This procedure finds a particular block is on a badblocks
 * list.
 */
int ext2fs_u32_list_find(ext2_u32_list bb, __u32 blk)
{
        int     low, high, mid;

        if (bb->magic != EXT2_ET_MAGIC_BADBLOCKS_LIST)
                return -1;

        if (bb->num == 0)
                return -1;

        low = 0;
        high = bb->num-1;
        if (blk == bb->list[low])
                return low;
        if (blk == bb->list[high])
                return high;

        while (low < high) {
                mid = (low+high)/2;
                if (mid == low || mid == high)
                        break;
                if (blk == bb->list[mid])
                        return mid;
                if (blk < bb->list[mid])
                        high = mid;
                else
                        low = mid;
        }
        return -1;
}

/*
 * This procedure tests to see if a particular block is on a badblocks
 * list.
 */
int ext2fs_u32_list_test(ext2_u32_list bb, __u32 blk)
{
        if (ext2fs_u32_list_find(bb, blk) < 0)
                return 0;
        else
                return 1;
}

int ext2fs_badblocks_list_test(ext2_badblocks_list bb, blk_t blk)
{
        return ext2fs_u32_list_test((ext2_u32_list) bb, (__u32) blk);
}


/*
 * Remove a block from the badblock list
 */
int ext2fs_u32_list_del(ext2_u32_list bb, __u32 blk)
{
        int     remloc, i;

        if (bb->num == 0)
                return -1;

        remloc = ext2fs_u32_list_find(bb, blk);
        if (remloc < 0)
                return -1;

        for (i = remloc; i < bb->num - 1; i++)
                bb->list[i] = bb->list[i+1];
        bb->num--;
        return 0;
}

void ext2fs_badblocks_list_del(ext2_u32_list bb, __u32 blk)
{
        ext2fs_u32_list_del(bb, blk);
}

errcode_t ext2fs_u32_list_iterate_begin(ext2_u32_list bb,
                                        ext2_u32_iterate *ret)
{
        ext2_u32_iterate iter;
        errcode_t               retval;

        EXT2_CHECK_MAGIC(bb, EXT2_ET_MAGIC_BADBLOCKS_LIST);

        retval = ext2fs_get_mem(sizeof(struct ext2_struct_u32_iterate), &iter);
        if (retval)
                return retval;

        iter->magic = EXT2_ET_MAGIC_BADBLOCKS_ITERATE;
        iter->bb = bb;
        iter->ptr = 0;
        *ret = iter;
        return 0;
}

errcode_t ext2fs_badblocks_list_iterate_begin(ext2_badblocks_list bb,
                                              ext2_badblocks_iterate *ret)
{
        return ext2fs_u32_list_iterate_begin((ext2_u32_list) bb,
                                              (ext2_u32_iterate *) ret);
}


int ext2fs_u32_list_iterate(ext2_u32_iterate iter, __u32 *blk)
{
        ext2_u32_list   bb;

        if (iter->magic != EXT2_ET_MAGIC_BADBLOCKS_ITERATE)
                return 0;

        bb = iter->bb;

        if (bb->magic != EXT2_ET_MAGIC_BADBLOCKS_LIST)
                return 0;

        if (iter->ptr < bb->num) {
                *blk = bb->list[iter->ptr++];
                return 1;
        }
        *blk = 0;
        return 0;
}

int ext2fs_badblocks_list_iterate(ext2_badblocks_iterate iter, blk_t *blk)
{
        return ext2fs_u32_list_iterate((ext2_u32_iterate) iter,
                                       (__u32 *) blk);
}


void ext2fs_u32_list_iterate_end(ext2_u32_iterate iter)
{
        if (!iter || (iter->magic != EXT2_ET_MAGIC_BADBLOCKS_ITERATE))
                return;

        iter->bb = 0;
        ext2fs_free_mem(&iter);
}

void ext2fs_badblocks_list_iterate_end(ext2_badblocks_iterate iter)
{
        ext2fs_u32_list_iterate_end((ext2_u32_iterate) iter);
}


int ext2fs_u32_list_equal(ext2_u32_list bb1, ext2_u32_list bb2)
{
        EXT2_CHECK_MAGIC(bb1, EXT2_ET_MAGIC_BADBLOCKS_LIST);
        EXT2_CHECK_MAGIC(bb2, EXT2_ET_MAGIC_BADBLOCKS_LIST);

        if (bb1->num != bb2->num)
                return 0;

        if (memcmp(bb1->list, bb2->list, bb1->num * sizeof(blk_t)) != 0)
                return 0;
        return 1;
}

int ext2fs_badblocks_equal(ext2_badblocks_list bb1, ext2_badblocks_list bb2)
{
        return ext2fs_u32_list_equal((ext2_u32_list) bb1,
                                     (ext2_u32_list) bb2);
}

int ext2fs_u32_list_count(ext2_u32_list bb)
{
        return bb->num;
}