source: vbox/trunk/src/libs/liblzma-5.4.1/common/filter_flags_decoder.c

///////////////////////////////////////////////////////////////////////////////
//
/// \file       filter_flags_decoder.c
/// \brief      Decodes a Filter Flags field
//
//  Author:     Lasse Collin
//
//  This file has been put into the public domain.
//  You can do whatever you want with this file.
//
///////////////////////////////////////////////////////////////////////////////

#include "filter_decoder.h"


extern LZMA_API(lzma_ret)
lzma_filter_flags_decode(
                lzma_filter *filter, const lzma_allocator *allocator,
                const uint8_t *in, size_t *in_pos, size_t in_size)
{
        // Set the pointer to NULL so the caller can always safely free it.
        filter->options = NULL;

        // Filter ID
        return_if_error(lzma_vli_decode(&filter->id, NULL,
                        in, in_pos, in_size));

        if (filter->id >= LZMA_FILTER_RESERVED_START)
                return LZMA_DATA_ERROR;

        // Size of Properties
        lzma_vli props_size;
        return_if_error(lzma_vli_decode(&props_size, NULL,
                        in, in_pos, in_size));

        // Filter Properties
        if (in_size - *in_pos < props_size)
                return LZMA_DATA_ERROR;

        const lzma_ret ret = lzma_properties_decode(
                        filter, allocator, in + *in_pos, props_size);

        *in_pos += props_size;

        return ret;
}