static int64_t seek_to_sector(BlockDriverState *bs, int64_t sector_num) { BDRVBochsState *s = bs->opaque; uint64_t offset = sector_num * 512; uint64_t extent_index, extent_offset, bitmap_offset; char bitmap_entry; // seek to sector extent_index = offset / s->extent_size; extent_offset = (offset % s->extent_size) / 512; if (s->catalog_bitmap[extent_index] == 0xffffffff) { return -1; /* not allocated */ } bitmap_offset = s->data_offset + (512 * (uint64_t) s->catalog_bitmap[extent_index] * (s->extent_blocks + s->bitmap_blocks)); /* read in bitmap for current extent */ if (bdrv_pread(bs->file, bitmap_offset + (extent_offset / 8), &bitmap_entry, 1) != 1) { return -1; } if (!((bitmap_entry >> (extent_offset % 8)) & 1)) { return -1; /* not allocated */ } return bitmap_offset + (512 * (s->bitmap_blocks + extent_offset)); }
static int64_t seek_to_sector(BlockDriverState *bs, int64_t sector_num) { BDRVBochsState *s = bs->opaque; uint64_t offset = sector_num * 512; uint64_t extent_index, extent_offset, bitmap_offset; char bitmap_entry;  