source: vbox/trunk/src/libs/liblzma-5.6.4/simple/sparc.c@ 109046

// SPDX-License-Identifier: 0BSD

///////////////////////////////////////////////////////////////////////////////
//
/// \file       sparc.c
/// \brief      Filter for SPARC binaries
///
//  Authors:    Igor Pavlov
//              Lasse Collin
//
///////////////////////////////////////////////////////////////////////////////

#include "simple_private.h"


static size_t
sparc_code(void *simple lzma_attribute((__unused__)),
                uint32_t now_pos, bool is_encoder,
                uint8_t *buffer, size_t size)
{
        size_t i;
        for (i = 0; i + 4 <= size; i += 4) {

                if ((buffer[i] == 0x40 && (buffer[i + 1] & 0xC0) == 0x00)
                                || (buffer[i] == 0x7F
                                && (buffer[i + 1] & 0xC0) == 0xC0)) {

                        uint32_t src = ((uint32_t)buffer[i + 0] << 24)
                                        | ((uint32_t)buffer[i + 1] << 16)
                                        | ((uint32_t)buffer[i + 2] << 8)
                                        | ((uint32_t)buffer[i + 3]);

                        src <<= 2;

                        uint32_t dest;
                        if (is_encoder)
                                dest = now_pos + (uint32_t)(i) + src;
                        else
                                dest = src - (now_pos + (uint32_t)(i));

                        dest >>= 2;

                        dest = (((0 - ((dest >> 22) & 1)) << 22) & 0x3FFFFFFF)
                                        | (dest & 0x3FFFFF)
                                        | 0x40000000;

                        buffer[i + 0] = (uint8_t)(dest >> 24);
                        buffer[i + 1] = (uint8_t)(dest >> 16);
                        buffer[i + 2] = (uint8_t)(dest >> 8);
                        buffer[i + 3] = (uint8_t)(dest);
                }
        }

        return i;
}


static lzma_ret
sparc_coder_init(lzma_next_coder *next, const lzma_allocator *allocator,
                const lzma_filter_info *filters, bool is_encoder)
{
        return lzma_simple_coder_init(next, allocator, filters,
                        &sparc_code, 0, 4, 4, is_encoder);
}


#ifdef HAVE_ENCODER_SPARC
extern lzma_ret
lzma_simple_sparc_encoder_init(lzma_next_coder *next,
                const lzma_allocator *allocator,
                const lzma_filter_info *filters)
{
        return sparc_coder_init(next, allocator, filters, true);
}
#endif


#ifdef HAVE_DECODER_SPARC
extern lzma_ret
lzma_simple_sparc_decoder_init(lzma_next_coder *next,
                const lzma_allocator *allocator,
                const lzma_filter_info *filters)
{
        return sparc_coder_init(next, allocator, filters, false);
}
#endif