1 // SPDX-License-Identifier: 0BSD 2 3 /////////////////////////////////////////////////////////////////////////////// 4 // 5 /// \file arm.c 6 /// \brief Filter for ARM binaries 7 /// 8 // Authors: Igor Pavlov 9 // Lasse Collin 10 // 11 /////////////////////////////////////////////////////////////////////////////// 12 13 #include "simple_private.h" 14 15 16 static size_t 17 arm_code(void *simple lzma_attribute((__unused__)), 18 uint32_t now_pos, bool is_encoder, 19 uint8_t *buffer, size_t size) 20 { 21 size &= ~(size_t)3; 22 23 size_t i; 24 for (i = 0; i < size; i += 4) { 25 if (buffer[i + 3] == 0xEB) { 26 uint32_t src = ((uint32_t)(buffer[i + 2]) << 16) 27 | ((uint32_t)(buffer[i + 1]) << 8) 28 | (uint32_t)(buffer[i + 0]); 29 src <<= 2; 30 31 uint32_t dest; 32 if (is_encoder) 33 dest = now_pos + (uint32_t)(i) + 8 + src; 34 else 35 dest = src - (now_pos + (uint32_t)(i) + 8); 36 37 dest >>= 2; 38 buffer[i + 2] = (dest >> 16); 39 buffer[i + 1] = (dest >> 8); 40 buffer[i + 0] = dest; 41 } 42 } 43 44 return i; 45 } 46 47 48 static lzma_ret 49 arm_coder_init(lzma_next_coder *next, const lzma_allocator *allocator, 50 const lzma_filter_info *filters, bool is_encoder) 51 { 52 return lzma_simple_coder_init(next, allocator, filters, 53 &arm_code, 0, 4, 4, is_encoder); 54 } 55 56 57 #ifdef HAVE_ENCODER_ARM 58 extern lzma_ret 59 lzma_simple_arm_encoder_init(lzma_next_coder *next, 60 const lzma_allocator *allocator, 61 const lzma_filter_info *filters) 62 { 63 return arm_coder_init(next, allocator, filters, true); 64 } 65 #endif 66 67 68 #ifdef HAVE_DECODER_ARM 69 extern lzma_ret 70 lzma_simple_arm_decoder_init(lzma_next_coder *next, 71 const lzma_allocator *allocator, 72 const lzma_filter_info *filters) 73 { 74 return arm_coder_init(next, allocator, filters, false); 75 } 76 #endif 77