src/liblzma/simple/sparc.c

   1 ///////////////////////////////////////////////////////////////////////////////
   2 //
   3 /// \file       sparc.c
   4 /// \brief      Filter for SPARC binaries
   5 //
   6 //  Copyright (C) 1999-2006 Igor Pavlov
   7 //  Copyright (C) 2007 Lasse Collin
   8 //
   9 //  This library is free software; you can redistribute it and/or
  10 //  modify it under the terms of the GNU Lesser General Public
  11 //  License as published by the Free Software Foundation; either
  12 //  version 2.1 of the License, or (at your option) any later version.
  13 //
  14 //  This library is distributed in the hope that it will be useful,
  15 //  but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 //  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17 //  Lesser General Public License for more details.
  18 //
  19 ///////////////////////////////////////////////////////////////////////////////
  20
  21 #include "simple_private.h"
  22
  23
  24 static size_t
  25 sparc_code(lzma_simple *simple lzma_attribute((unused)),
  26                 uint32_t now_pos, bool is_encoder,
  27                 uint8_t *buffer, size_t size)
  28 {
  29         size_t i;
  30         for (i = 0; i + 4 <= size; i += 4) {
  31
  32                 if ((buffer[i] == 0x40 && (buffer[i + 1] & 0xC0) == 0x00)
  33                                 || (buffer[i] == 0x7F
  34                                 && (buffer[i + 1] & 0xC0) == 0xC0)) {
  35
  36                         uint32_t src = ((uint32_t)buffer[i + 0] << 24)
  37                                         | ((uint32_t)buffer[i + 1] << 16)
  38                                         | ((uint32_t)buffer[i + 2] << 8)
  39                                         | ((uint32_t)buffer[i + 3]);
  40
  41                         src <<= 2;
  42
  43                         uint32_t dest;
  44                         if (is_encoder)
  45                                 dest = now_pos + (uint32_t)(i) + src;
  46                         else
  47                                 dest = src - (now_pos + (uint32_t)(i));
  48
  49                         dest >>= 2;
  50
  51                         dest = (((0 - ((dest >> 22) & 1)) << 22) & 0x3FFFFFFF)
  52                                         | (dest & 0x3FFFFF)
  53                                         | 0x40000000;
  54
  55                         buffer[i + 0] = (uint8_t)(dest >> 24);
  56                         buffer[i + 1] = (uint8_t)(dest >> 16);
  57                         buffer[i + 2] = (uint8_t)(dest >> 8);
  58                         buffer[i + 3] = (uint8_t)(dest);
  59                 }
  60         }
  61
  62         return i;
  63 }
  64
  65
  66 static lzma_ret
  67 sparc_coder_init(lzma_next_coder *next, lzma_allocator *allocator,
  68                 const lzma_filter_info *filters, bool is_encoder)
  69 {
  70         return lzma_simple_coder_init(next, allocator, filters,
  71                         &sparc_code, 0, 4, is_encoder);
  72 }
  73
  74
  75 extern lzma_ret
  76 lzma_simple_sparc_encoder_init(lzma_next_coder *next,
  77                 lzma_allocator *allocator, const lzma_filter_info *filters)
  78 {
  79         return sparc_coder_init(next, allocator, filters, true);
  80 }
  81
  82
  83 extern lzma_ret
  84 lzma_simple_sparc_decoder_init(lzma_next_coder *next,
  85                 lzma_allocator *allocator, const lzma_filter_info *filters)
  86 {
  87         return sparc_coder_init(next, allocator, filters, false);
  88 }