The R Project SVN R

///////////////////////////////////////////////////////////////////////////////
//
/// \file       check.c
/// \brief      Single API to access different integrity checks
//
//  Author:     Lasse Collin
//
//  This file has been put into the public domain.
//  You can do whatever you want with this file.
//
///////////////////////////////////////////////////////////////////////////////

#include "check.h"


extern LZMA_API(lzma_bool)
lzma_check_is_supported(lzma_check type)
{
    if ((unsigned int)(type) > LZMA_CHECK_ID_MAX)
        return false;

    static const lzma_bool available_checks[LZMA_CHECK_ID_MAX + 1] = {
        true,   // LZMA_CHECK_NONE

#ifdef HAVE_CHECK_CRC32
        true,
#else
        false,
#endif

        false,  // Reserved
        false,  // Reserved

#ifdef HAVE_CHECK_CRC64
        true,
#else
        false,
#endif

        false,  // Reserved
        false,  // Reserved
        false,  // Reserved
        false,  // Reserved
        false,  // Reserved

#ifdef HAVE_CHECK_SHA256
        true,
#else
        false,
#endif

        false,  // Reserved
        false,  // Reserved
        false,  // Reserved
        false,  // Reserved
        false,  // Reserved
    };

    return available_checks[(unsigned int)(type)];
}


extern LZMA_API(uint32_t)
lzma_check_size(lzma_check type)
{
    if ((unsigned int)(type) > LZMA_CHECK_ID_MAX)
        return UINT32_MAX;

    // See file-format.txt section 2.1.1.2.
    static const uint8_t check_sizes[LZMA_CHECK_ID_MAX + 1] = {
        0,
        4, 4, 4,
        8, 8, 8,
        16, 16, 16,
        32, 32, 32,
        64, 64, 64
    };

    return check_sizes[(unsigned int)(type)];
}


extern void
lzma_check_init(lzma_check_state *check, lzma_check type)
{
    switch (type) {
    case LZMA_CHECK_NONE:
        break;

#ifdef HAVE_CHECK_CRC32
    case LZMA_CHECK_CRC32:
        check->state.crc32 = 0;
        break;
#endif

#ifdef HAVE_CHECK_CRC64
    case LZMA_CHECK_CRC64:
        check->state.crc64 = 0;
        break;
#endif

#ifdef HAVE_CHECK_SHA256
    case LZMA_CHECK_SHA256:
        lzma_sha256_init(check);
        break;
#endif

    default:
        break;
    }

    return;
}


extern void
lzma_check_update(lzma_check_state *check, lzma_check type,
        const uint8_t *buf, size_t size)
{
    switch (type) {
#ifdef HAVE_CHECK_CRC32
    case LZMA_CHECK_CRC32:
        check->state.crc32 = lzma_crc32(buf, size, check->state.crc32);
        break;
#endif

#ifdef HAVE_CHECK_CRC64
    case LZMA_CHECK_CRC64:
        check->state.crc64 = lzma_crc64(buf, size, check->state.crc64);
        break;
#endif

#ifdef HAVE_CHECK_SHA256
    case LZMA_CHECK_SHA256:
        lzma_sha256_update(buf, size, check);
        break;
#endif

    default:
        break;
    }

    return;
}


extern void
lzma_check_finish(lzma_check_state *check, lzma_check type)
{
    switch (type) {
#ifdef HAVE_CHECK_CRC32
    case LZMA_CHECK_CRC32:
        check->buffer.u32[0] = integer_le_32(check->state.crc32);
        break;
#endif

#ifdef HAVE_CHECK_CRC64
    case LZMA_CHECK_CRC64:
        check->buffer.u64[0] = integer_le_64(check->state.crc64);
        break;
#endif

#ifdef HAVE_CHECK_SHA256
    case LZMA_CHECK_SHA256:
        lzma_sha256_finish(check);
        break;
#endif

    default:
        break;
    }

    return;
}