From 9533dc84d7addf792db4f4702b6fc7d7ddd20e78 Mon Sep 17 00:00:00 2001 From: David Oberhollenzer Date: Sun, 1 Sep 2019 14:35:03 +0200 Subject: Install libsquashfs.so headers on the system in "sqfs" subdirectory Signed-off-by: David Oberhollenzer --- include/sqfs/meta_writer.h | 87 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 87 insertions(+) create mode 100644 include/sqfs/meta_writer.h (limited to 'include/sqfs/meta_writer.h') diff --git a/include/sqfs/meta_writer.h b/include/sqfs/meta_writer.h new file mode 100644 index 0000000..762cc38 --- /dev/null +++ b/include/sqfs/meta_writer.h @@ -0,0 +1,87 @@ +/* SPDX-License-Identifier: GPL-3.0-or-later */ +/* + * meta_writer.h + * + * Copyright (C) 2019 David Oberhollenzer + */ +#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 */ -- cgit v1.2.3