| /* |
| * bitmaps.c --- routines to read, write, and manipulate the inode and |
| * block bitmaps. |
| * |
| * Copyright (C) 1993, 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 <stdlib.h> |
| #include <fcntl.h> |
| #include <time.h> |
| #include <sys/stat.h> |
| #include <sys/types.h> |
| #if HAVE_ERRNO_H |
| #include <errno.h> |
| #endif |
| |
| #include <linux/ext2_fs.h> |
| |
| #include "ext2fs.h" |
| |
| static errcode_t make_bitmap(__u32 start, __u32 end, __u32 real_end, |
| const char *descr, char *init_map, |
| ext2fs_generic_bitmap *ret) |
| { |
| ext2fs_generic_bitmap bitmap; |
| size_t size; |
| |
| bitmap = malloc(sizeof(struct ext2fs_struct_generic_bitmap)); |
| if (!bitmap) |
| return ENOMEM; |
| |
| bitmap->magic = EXT2_ET_MAGIC_GENERIC_BITMAP; |
| bitmap->fs = NULL; |
| bitmap->start = start; |
| bitmap->end = end; |
| bitmap->real_end = real_end; |
| bitmap->base_error_code = EXT2_ET_BAD_GENERIC_MARK; |
| if (descr) { |
| bitmap->description = malloc(strlen(descr)+1); |
| if (!bitmap->description) { |
| free(bitmap); |
| return ENOMEM; |
| } |
| strcpy(bitmap->description, descr); |
| } else |
| bitmap->description = 0; |
| |
| size = (size_t) (((bitmap->real_end - bitmap->start) / 8) + 1); |
| bitmap->bitmap = malloc(size); |
| if (!bitmap->bitmap) { |
| free(bitmap->description); |
| free(bitmap); |
| return ENOMEM; |
| } |
| |
| if (init_map) |
| memcpy(bitmap->bitmap, init_map, size); |
| else |
| memset(bitmap->bitmap, 0, size); |
| *ret = bitmap; |
| return 0; |
| } |
| |
| errcode_t ext2fs_allocate_generic_bitmap(__u32 start, |
| __u32 end, |
| __u32 real_end, |
| const char *descr, |
| ext2fs_generic_bitmap *ret) |
| { |
| return make_bitmap(start, end, real_end, descr, 0, ret); |
| } |
| |
| errcode_t ext2fs_copy_bitmap(ext2fs_generic_bitmap src, |
| ext2fs_generic_bitmap *dest) |
| { |
| errcode_t retval; |
| ext2fs_generic_bitmap new; |
| |
| retval = make_bitmap(src->start, src->end, src->real_end, |
| src->description, src->bitmap, &new); |
| if (retval) |
| return retval; |
| new->magic = src->magic; |
| new->fs = src->fs; |
| new->base_error_code = src->base_error_code; |
| *dest = new; |
| return 0; |
| } |
| |
| |
| errcode_t ext2fs_allocate_inode_bitmap(ext2_filsys fs, |
| const char *descr, |
| ext2fs_inode_bitmap *ret) |
| { |
| ext2fs_inode_bitmap bitmap; |
| errcode_t retval; |
| __u32 start, end, real_end; |
| |
| EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); |
| |
| fs->write_bitmaps = ext2fs_write_bitmaps; |
| |
| start = 1; |
| end = fs->super->s_inodes_count; |
| real_end = (EXT2_INODES_PER_GROUP(fs->super) * fs->group_desc_count); |
| |
| retval = ext2fs_allocate_generic_bitmap(start, end, real_end, |
| descr, &bitmap); |
| if (retval) |
| return retval; |
| |
| bitmap->magic = EXT2_ET_MAGIC_INODE_BITMAP; |
| bitmap->fs = fs; |
| bitmap->base_error_code = EXT2_ET_BAD_INODE_MARK; |
| |
| *ret = bitmap; |
| return 0; |
| } |
| |
| errcode_t ext2fs_allocate_block_bitmap(ext2_filsys fs, |
| const char *descr, |
| ext2fs_block_bitmap *ret) |
| { |
| ext2fs_block_bitmap bitmap; |
| errcode_t retval; |
| __u32 start, end, real_end; |
| |
| EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); |
| |
| fs->write_bitmaps = ext2fs_write_bitmaps; |
| |
| start = fs->super->s_first_data_block; |
| end = fs->super->s_blocks_count-1; |
| real_end = (EXT2_BLOCKS_PER_GROUP(fs->super) |
| * fs->group_desc_count)-1 + start; |
| |
| retval = ext2fs_allocate_generic_bitmap(start, end, real_end, |
| descr, &bitmap); |
| if (retval) |
| return retval; |
| |
| bitmap->magic = EXT2_ET_MAGIC_BLOCK_BITMAP; |
| bitmap->fs = fs; |
| bitmap->base_error_code = EXT2_ET_BAD_BLOCK_MARK; |
| |
| *ret = bitmap; |
| return 0; |
| } |
| |
| errcode_t ext2fs_fudge_inode_bitmap_end(ext2fs_inode_bitmap bitmap, |
| ino_t end, ino_t *oend) |
| { |
| EXT2_CHECK_MAGIC(bitmap, EXT2_ET_MAGIC_INODE_BITMAP); |
| |
| if (end > bitmap->real_end) |
| return EXT2_ET_FUDGE_INODE_BITMAP_END; |
| if (oend) |
| *oend = bitmap->end; |
| bitmap->end = end; |
| return 0; |
| } |
| |
| errcode_t ext2fs_fudge_block_bitmap_end(ext2fs_block_bitmap bitmap, |
| blk_t end, blk_t *oend) |
| { |
| EXT2_CHECK_MAGIC(bitmap, EXT2_ET_MAGIC_BLOCK_BITMAP); |
| |
| if (end > bitmap->real_end) |
| return EXT2_ET_FUDGE_BLOCK_BITMAP_END; |
| if (oend) |
| *oend = bitmap->end; |
| bitmap->end = end; |
| return 0; |
| } |
| |
| void ext2fs_clear_inode_bitmap(ext2fs_inode_bitmap bitmap) |
| { |
| if (!bitmap || (bitmap->magic != EXT2_ET_MAGIC_INODE_BITMAP)) |
| return; |
| |
| memset(bitmap->bitmap, 0, |
| (size_t) (((bitmap->real_end - bitmap->start) / 8) + 1)); |
| } |
| |
| void ext2fs_clear_block_bitmap(ext2fs_block_bitmap bitmap) |
| { |
| if (!bitmap || (bitmap->magic != EXT2_ET_MAGIC_BLOCK_BITMAP)) |
| return; |
| |
| memset(bitmap->bitmap, 0, |
| (size_t) (((bitmap->real_end - bitmap->start) / 8) + 1)); |
| } |