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* Copyright (C) 2000 Richard Guenther
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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#include "swfs_ctree.h"
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/* File instance, flags are
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* SWF_NOT_IN_CORE - swfile.{size,cluster_cnt,clusters} is not filled in
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* SWF_UNLINKED - on disk file is unlinked
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* SWF_DIRTY - cluster list is dirty */
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#define SWF_NOT_IN_CORE 1
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#define SWF_UNLINKED 2
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struct swfile *next_swfile_hash;
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struct swfile **pprev_swfile_hash;
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pthread_mutex_t mx; /* protects flags & clusters */
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int usage; /* number of references to this struct swfile,
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* protected by FILES lock. */
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int flags; /* SWF_* */
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/* Fields created out of the file metadata */
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struct ctree *clusters; /* cluster tree */
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/* Gets a reference to the file with the specified name -
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* creates it, if it does not exist and FILEGET_CREAT is
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* set. If FILEGET_READCLUSTERS is set, the cluster tree
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* of the file is brought into the core.
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* Returns a reference to the file or NULL on error. */
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#define FILEGET_READCLUSTERS 1
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#define FILEGET_CREAT 2
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static struct swfile *file_get(long name, int flags);
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/* Releases the file reference, if FILEPUT_SYNC is set,
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* the actual cluster tree is synced to the disk, if
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* FILEPUT_UNLINK is specified, the on-disk representation
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* is unlinked and as the last reference goes away, the
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* file and its name is freed. */
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#define FILEPUT_UNLINK 1
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#define FILEPUT_SYNC 2
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static void file_put(struct swfile *f, int flags);
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/* Syncs all hashed and modified file ctrees to disk. */
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static void file_sync();
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/* Get a reference to the cluster containing offset using the
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* specified flags. Stores the offset of the cluster start in cstart.
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* Return values/flags like get_cluster. */
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static struct swcluster *file_getcluster(struct swfile *f,
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s64 offset, s64 *cstart,
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/* Get a reference to the cluster containing offset using the
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* specified flags. Stores the offset of the cluster start in cstart.
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* Return values/flags like get_cluster. If the cluster is shared,
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* copy it and replace it with the copy. */
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static struct swcluster *file_getcluster_private(struct swfile *f,
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s64 offset, s64 *cstart,
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/* Truncate the file to the given size. Returns 0 on success
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static int file_truncate(struct swfile *f, s64 size);
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/* Insert count bytes from position spos in file sf into file df
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* at position dpos. Returns -1 on error, 0 on success. */
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static int file_insert(struct swfile *df, s64 dpos,
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struct swfile *sf, s64 spos, s64 count);
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/* Replaces count bytes of file df from position dpos with
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* data from position spos out of file sf. Returns 0 on success,
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static int file_replace(struct swfile *df, s64 dpos,
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struct swfile *sf, s64 spos, s64 count);
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/* Removes count bytes from position dpos out of file df. Returns
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* 0 on success, -1 on error. */
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static int file_cut(struct swfile *df, s64 dpos, s64 count);
added
removed
src/swapfile/swfs_file.h
