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/* SPDX-License-Identifier: GPL-3.0-or-later */
/*
* meta_writer.h
*
* Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
*/
#ifndef META_WRITER_H
#define META_WRITER_H
#include "config.h"
#include "compress.h"
#include "squashfs.h"
#include "id_table.h"
#include "fstree.h"
typedef struct {
tree_node_t *node;
uint32_t block;
uint32_t index;
} idx_ref_t;
typedef struct {
size_t num_nodes;
size_t max_nodes;
idx_ref_t idx_nodes[];
} dir_index_t;
typedef struct meta_writer_t meta_writer_t;
/* Create a meta data reader using a given compressor to compress data.
Internally prints error message to stderr on failure.
If keep_in_mem is true, the blocks are collected in memory and must
be explicitly flushed to disk using meta_write_write_to_file.
*/
meta_writer_t *meta_writer_create(int fd, compressor_t *cmp, bool keep_in_mem);
void meta_writer_destroy(meta_writer_t *m);
/* Compress and flush the currently unfinished block to disk. Returns 0 on
success, internally prints error message to stderr on failure */
int meta_writer_flush(meta_writer_t *m);
/* Returns 0 on success. Prints error message to stderr on failure. */
int meta_writer_append(meta_writer_t *m, const void *data, size_t size);
/* Query the current block start position and offset within the block */
void meta_writer_get_position(const meta_writer_t *m, uint64_t *block_start,
uint32_t *offset);
/* Reset all internal state, including the current block start position. */
void meta_writer_reset(meta_writer_t *m);
/* If created with keep_in_mem true, write the collected blocks to disk.
Does not flush the current block. Writes error messages to stderr and
returns non-zero on failure. */
int meta_write_write_to_file(meta_writer_t *m);
/*
High level helper function that writes squashfs directory entries to
a meta data writer.
The dir_info_t structure is used to generate the listing and updated
accordingly (such as writing back the header position and total size).
A directory index is created on the fly and returned in *index.
A single free() call is sufficient.
Returns 0 on success. Prints error messages to stderr on failure.
*/
int meta_writer_write_dir(meta_writer_t *dm, dir_info_t *dir,
dir_index_t **index);
/*
High level helper function to serialize a tree_node_t to a squashfs inode
and write it to a meta data writer.
The inode is written to `im`. If it is a directory node, the directory
contents are written to `dm` using meta_writer_write_dir. The given
id_table_t is used to store the uid and gid on the fly and write the
coresponding indices to the inode structure.
Returns 0 on success. Prints error messages to stderr on failure.
*/
int meta_writer_write_inode(fstree_t *fs, id_table_t *idtbl, meta_writer_t *im,
meta_writer_t *dm, tree_node_t *node);
#endif /* META_WRITER_H */
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