1/////////////////////////////////////////////////////////////////////////////// 2// 3/// \file arm.c 4/// \brief Filter for ARM 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 18arm_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 if (buffer[i + 3] == 0xEB) { 25 uint32_t src = (buffer[i + 2] << 16) 26 | (buffer[i + 1] << 8) 27 | (buffer[i + 0]); 28 src <<= 2; 29 30 uint32_t dest; 31 if (is_encoder) 32 dest = now_pos + (uint32_t)(i) + 8 + src; 33 else 34 dest = src - (now_pos + (uint32_t)(i) + 8); 35 36 dest >>= 2; 37 buffer[i + 2] = (dest >> 16); 38 buffer[i + 1] = (dest >> 8); 39 buffer[i + 0] = dest; 40 } 41 } 42 43 return i; 44} 45 46 47static lzma_ret 48arm_coder_init(lzma_next_coder *next, lzma_allocator *allocator, 49 const lzma_filter_info *filters, bool is_encoder) 50{ 51 return lzma_simple_coder_init(next, allocator, filters, 52 &arm_code, 0, 4, 4, is_encoder); 53} 54 55 56extern lzma_ret 57lzma_simple_arm_encoder_init(lzma_next_coder *next, lzma_allocator *allocator, 58 const lzma_filter_info *filters) 59{ 60 return arm_coder_init(next, allocator, filters, true); 61} 62 63 64extern lzma_ret 65lzma_simple_arm_decoder_init(lzma_next_coder *next, lzma_allocator *allocator, 66 const lzma_filter_info *filters) 67{ 68 return arm_coder_init(next, allocator, filters, false); 69} 70