fs/squashfs/sqfs_decompressor.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) 2020 Bootlin
 *
 * Author: Joao Marcos Costa <joaomarcos.costa@bootlin.com>
 */

#include <errno.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#if IS_ENABLED(CONFIG_ZLIB)
#include <u-boot/zlib.h>
#endif

#include "sqfs_decompressor.h"
#include "sqfs_utils.h"

int sqfs_decompressor_init(struct squashfs_ctxt *ctxt)
{
	u16 comp_type = get_unaligned_le16(&ctxt->sblk->compression);

	switch (comp_type) {
#if IS_ENABLED(CONFIG_ZLIB)
	case SQFS_COMP_ZLIB:
		break;
#endif
	default:
		printf("Error: unknown compression type.\n");
		return -EINVAL;
	}

	return 0;
}

void sqfs_decompressor_cleanup(struct squashfs_ctxt *ctxt)
{
	u16 comp_type = get_unaligned_le16(&ctxt->sblk->compression);

	switch (comp_type) {
#if IS_ENABLED(CONFIG_ZLIB)
	case SQFS_COMP_ZLIB:
		break;
#endif
	}
}

#if IS_ENABLED(CONFIG_ZLIB)
static void zlib_decompression_status(int ret)
{
	switch (ret) {
	case Z_BUF_ERROR:
		printf("Error: 'dest' buffer is not large enough.\n");
		break;
	case Z_DATA_ERROR:
		printf("Error: corrupted compressed data.\n");
		break;
	case Z_MEM_ERROR:
		printf("Error: insufficient memory.\n");
		break;
	}
}
#endif

int sqfs_decompress(struct squashfs_ctxt *ctxt, void *dest,
		    unsigned long *dest_len, void *source, u32 src_len)
{
	u16 comp_type = get_unaligned_le16(&ctxt->sblk->compression);
	int ret = 0;

	switch (comp_type) {
#if IS_ENABLED(CONFIG_ZLIB)
	case SQFS_COMP_ZLIB:
		ret = uncompress(dest, dest_len, source, src_len);
		if (ret) {
			zlib_decompression_status(ret);
			return -EINVAL;
		}

		break;
#endif
	default:
		printf("Error: unknown compression type.\n");
		return -EINVAL;
	}

	return ret;
}