diff options
Diffstat (limited to 'qemu/roms/openbios/fs/hfsplus/hfsp_blockiter.c')
| -rw-r--r-- | qemu/roms/openbios/fs/hfsplus/hfsp_blockiter.c | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/qemu/roms/openbios/fs/hfsplus/hfsp_blockiter.c b/qemu/roms/openbios/fs/hfsplus/hfsp_blockiter.c new file mode 100644 index 000000000..e91009229 --- /dev/null +++ b/qemu/roms/openbios/fs/hfsplus/hfsp_blockiter.c @@ -0,0 +1,141 @@ +/* + * libhfs - library for reading and writing Macintosh HFS volumes + * + * The iterator shown here iterates over the blocks of a fork. + * + * Copyright (C) 2000 Klaus Halfmann <khalfmann@libra.de> + * Original work by 1996-1998 Robert Leslie <rob@mars.org> + * other work 2000 from Brad Boyer (flar@pants.nu) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, + * MA 02110-1301, USA. + * + * $Id: blockiter.c,v 1.2 2000/10/17 05:58:46 hasi Exp $ + */ + +#include "config.h" +#include "libhfsp.h" +#include "blockiter.h" +#include "volume.h" +#include "record.h" +#include "btree.h" +#include "os.h" +#include "swab.h" +#include "hfstime.h" + +/* Initialize iterator for a given fork */ +void +blockiter_init(blockiter* b, volume* vol, hfsp_fork_raw* f, + UInt8 forktype, UInt32 fileId) +{ + b->vol = vol; + b->curr_block = 0; + b->block = 0; + b->max_block = f->total_blocks; + b->fileId = fileId; + b->index = 0; + b->file = f->extents; + b->e = f->extents; + b->forktype = forktype; + b->in_extent = 0; +} + +/* get next extent record when needed */ +static int +blockiter_next_extent(blockiter *b) +{ + btree* extents_tree = volume_get_extents_tree(b->vol); + int err; + + b->index = 0; + if (b->in_extent) // already using extents record ? + { + err = record_next_extent(&b->er); + // Hope there is no need to check this ... + // if (b->er.key.start_block != b->curr_block) + // HFSP_ERROR(ENOENT, + // "Extents record inconistent"); + } + else + { + err = record_init_file(&b->er, extents_tree, b->forktype, + b->fileId, b->curr_block); + b->in_extent = -1; // true + } + b->e = b->er.extent; + return err; +} + +/* find next block of the fork iterating over */ +int +blockiter_next(blockiter *b) +{ + b->curr_block ++; + b->block ++; + if (b->curr_block >= b->max_block) + return -1; // end of Blocks, but no error + // in current part of extent ? + if (b->block >= b->e->block_count) + { + b->index++; + b->block = 0; // reset relative position + b->e++; + if (b -> index >= 8) // need to fetch another extent + { + if (blockiter_next_extent(b)) + HFSP_ERROR(ENOENT, "Extends record not found."); + } + } + return 0; + + fail: + return -1; +} + +/* skip the indicated number of blocks */ +int +blockiter_skip(blockiter *b, UInt32 skip) +{ + while (skip > 0) + { + // Skip to skip or end of current extent + UInt32 diff = b->e->block_count - b->block; + if (skip < diff) + { + diff = skip; + skip = 0; + } + else + skip -= diff; + b->curr_block += diff; + b->block += diff; + if (b->curr_block >= b->max_block) + return -1; // end of Blocks, but no error + if (b->block >= b->e->block_count) + { + b->index++; + b->block = 0; // reset relative position + b->e++; + if (b -> index >= 8) // need to fetch another extent + { + if (blockiter_next_extent(b)) + HFSP_ERROR(ENOENT, "Extends record not found."); + } + } + } // we are here when skip was null, thats ok + return 0; + fail: + return -1; +} |