powerpc.c revision 213700
1/////////////////////////////////////////////////////////////////////////////// 2// 3/// \file powerpc.c 4/// \brief Filter for PowerPC (big endian) binaries 5/// 6// Authors: Igor Pavlov 7// Lasse Collin 8// 9// This file has been put into the public domain. 10// You can do whatever you want with this file. 11// 12/////////////////////////////////////////////////////////////////////////////// 13 14#include "simple_private.h" 15 16 17static size_t 18powerpc_code(lzma_simple *simple lzma_attribute((unused)), 19 uint32_t now_pos, bool is_encoder, 20 uint8_t *buffer, size_t size) 21{ 22 size_t i; 23 for (i = 0; i + 4 <= size; i += 4) { 24 // PowerPC branch 6(48) 24(Offset) 1(Abs) 1(Link) 25 if ((buffer[i] >> 2) == 0x12 26 && ((buffer[i + 3] & 3) == 1)) { 27 28 const uint32_t src = ((buffer[i + 0] & 3) << 24) 29 | (buffer[i + 1] << 16) 30 | (buffer[i + 2] << 8) 31 | (buffer[i + 3] & (~3)); 32 33 uint32_t dest; 34 if (is_encoder) 35 dest = now_pos + (uint32_t)(i) + src; 36 else 37 dest = src - (now_pos + (uint32_t)(i)); 38 39 buffer[i + 0] = 0x48 | ((dest >> 24) & 0x03); 40 buffer[i + 1] = (dest >> 16); 41 buffer[i + 2] = (dest >> 8); 42 buffer[i + 3] &= 0x03; 43 buffer[i + 3] |= dest; 44 } 45 } 46 47 return i; 48} 49 50 51static lzma_ret 52powerpc_coder_init(lzma_next_coder *next, lzma_allocator *allocator, 53 const lzma_filter_info *filters, bool is_encoder) 54{ 55 return lzma_simple_coder_init(next, allocator, filters, 56 &powerpc_code, 0, 4, 4, is_encoder); 57} 58 59 60extern lzma_ret 61lzma_simple_powerpc_encoder_init(lzma_next_coder *next, 62 lzma_allocator *allocator, const lzma_filter_info *filters) 63{ 64 return powerpc_coder_init(next, allocator, filters, true); 65} 66 67 68extern lzma_ret 69lzma_simple_powerpc_decoder_init(lzma_next_coder *next, 70 lzma_allocator *allocator, const lzma_filter_info *filters) 71{ 72 return powerpc_coder_init(next, allocator, filters, false); 73} 74