LXR busybox/e2fsprogs/old_e2fsprogs/ext2fs/rs

   1/* vi: set sw=4 ts=4: */
   2/*
   3 * rs_bitmap.c --- routine for changing the size of a bitmap
   4 *
   5 * Copyright (C) 1996, 1997 Theodore Ts'o.
   6 *
   7 * %Begin-Header%
   8 * This file may be redistributed under the terms of the GNU Public
   9 * License.
  10 * %End-Header%
  11 */
  12
  13#include <stdio.h>
  14#include <string.h>
  15#if HAVE_UNISTD_H
  16#include <unistd.h>
  17#endif
  18#include <fcntl.h>
  19#include <time.h>
  20#ifdef HAVE_SYS_STAT_H
  21#include <sys/stat.h>
  22#endif
  23#ifdef HAVE_SYS_TYPES_H
  24#include <sys/types.h>
  25#endif
  26
  27#include "ext2_fs.h"
  28#include "ext2fs.h"
  29
  30errcode_t ext2fs_resize_generic_bitmap(__u32 new_end, __u32 new_real_end,
  31                                       ext2fs_generic_bitmap bmap)
  32{
  33        errcode_t       retval;
  34        size_t          size, new_size;
  35        __u32           bitno;
  36
  37        if (!bmap)
  38                return EXT2_ET_INVALID_ARGUMENT;
  39
  40        EXT2_CHECK_MAGIC(bmap, EXT2_ET_MAGIC_GENERIC_BITMAP);
  41
  42        /*
  43         * If we're expanding the bitmap, make sure all of the new
  44         * parts of the bitmap are zero.
  45         */
  46        if (new_end > bmap->end) {
  47                bitno = bmap->real_end;
  48                if (bitno > new_end)
  49                        bitno = new_end;
  50                for (; bitno > bmap->end; bitno--)
  51                        ext2fs_clear_bit(bitno - bmap->start, bmap->bitmap);
  52        }
  53        if (new_real_end == bmap->real_end) {
  54                bmap->end = new_end;
  55                return 0;
  56        }
  57
  58        size = ((bmap->real_end - bmap->start) / 8) + 1;
  59        new_size = ((new_real_end - bmap->start) / 8) + 1;
  60
  61        if (size != new_size) {
  62                retval = ext2fs_resize_mem(size, new_size, &bmap->bitmap);
  63                if (retval)
  64                        return retval;
  65        }
  66        if (new_size > size)
  67                memset(bmap->bitmap + size, 0, new_size - size);
  68
  69        bmap->end = new_end;
  70        bmap->real_end = new_real_end;
  71        return 0;
  72}
  73
  74errcode_t ext2fs_resize_inode_bitmap(__u32 new_end, __u32 new_real_end,
  75                                     ext2fs_inode_bitmap bmap)
  76{
  77        errcode_t       retval;
  78
  79        if (!bmap)
  80                return EXT2_ET_INVALID_ARGUMENT;
  81
  82        EXT2_CHECK_MAGIC(bmap, EXT2_ET_MAGIC_INODE_BITMAP);
  83
  84        bmap->magic = EXT2_ET_MAGIC_GENERIC_BITMAP;
  85        retval = ext2fs_resize_generic_bitmap(new_end, new_real_end,
  86                                              bmap);
  87        bmap->magic = EXT2_ET_MAGIC_INODE_BITMAP;
  88        return retval;
  89}
  90
  91errcode_t ext2fs_resize_block_bitmap(__u32 new_end, __u32 new_real_end,
  92                                     ext2fs_block_bitmap bmap)
  93{
  94        errcode_t       retval;
  95
  96        if (!bmap)
  97                return EXT2_ET_INVALID_ARGUMENT;
  98
  99        EXT2_CHECK_MAGIC(bmap, EXT2_ET_MAGIC_BLOCK_BITMAP);
 100
 101        bmap->magic = EXT2_ET_MAGIC_GENERIC_BITMAP;
 102        retval = ext2fs_resize_generic_bitmap(new_end, new_real_end,
 103                                              bmap);
 104        bmap->magic = EXT2_ET_MAGIC_BLOCK_BITMAP;
 105        return retval;
 106}
 107
 108