1 ///////////////////////////////////////////////////////////////////////////////
4 /// \brief Filter for ARM-Thumb binaries
6 // Copyright (C) 1999-2006 Igor Pavlov
7 // Copyright (C) 2007 Lasse Collin
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.
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.
19 ///////////////////////////////////////////////////////////////////////////////
21 #include "simple_private.h"
25 armthumb_code(lzma_simple *simple lzma_attribute((unused)),
26 uint32_t now_pos, bool is_encoder,
27 uint8_t *buffer, size_t size)
30 for (i = 0; i + 4 <= size; i += 2) {
31 if ((buffer[i + 1] & 0xF8) == 0xF0
32 && (buffer[i + 3] & 0xF8) == 0xF8) {
33 uint32_t src = ((buffer[i + 1] & 0x7) << 19)
34 | (buffer[i + 0] << 11)
35 | ((buffer[i + 3] & 0x7) << 8)
42 dest = now_pos + (uint32_t)(i) + 4 + src;
44 dest = src - (now_pos + (uint32_t)(i) + 4);
47 buffer[i + 1] = 0xF0 | ((dest >> 19) & 0x7);
48 buffer[i + 0] = (dest >> 11);
49 buffer[i + 3] = 0xF8 | ((dest >> 8) & 0x7);
50 buffer[i + 2] = (dest);
60 armthumb_coder_init(lzma_next_coder *next, lzma_allocator *allocator,
61 const lzma_filter_info *filters, bool is_encoder)
63 return lzma_simple_coder_init(next, allocator, filters,
64 &armthumb_code, 0, 4, is_encoder);
69 lzma_simple_armthumb_encoder_init(lzma_next_coder *next,
70 lzma_allocator *allocator, const lzma_filter_info *filters)
72 return armthumb_coder_init(next, allocator, filters, true);
77 lzma_simple_armthumb_decoder_init(lzma_next_coder *next,
78 lzma_allocator *allocator, const lzma_filter_info *filters)
80 return armthumb_coder_init(next, allocator, filters, false);