xref: /freebsd/contrib/xz/src/liblzma/simple/sparc.c (revision cd0d51baaa4509a1db83251a601d34404d20c990)
1 ///////////////////////////////////////////////////////////////////////////////
2 //
3 /// \file       sparc.c
4 /// \brief      Filter for SPARC 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 
17 static size_t
18 sparc_code(void *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 
25 		if ((buffer[i] == 0x40 && (buffer[i + 1] & 0xC0) == 0x00)
26 				|| (buffer[i] == 0x7F
27 				&& (buffer[i + 1] & 0xC0) == 0xC0)) {
28 
29 			uint32_t src = ((uint32_t)buffer[i + 0] << 24)
30 					| ((uint32_t)buffer[i + 1] << 16)
31 					| ((uint32_t)buffer[i + 2] << 8)
32 					| ((uint32_t)buffer[i + 3]);
33 
34 			src <<= 2;
35 
36 			uint32_t dest;
37 			if (is_encoder)
38 				dest = now_pos + (uint32_t)(i) + src;
39 			else
40 				dest = src - (now_pos + (uint32_t)(i));
41 
42 			dest >>= 2;
43 
44 			dest = (((0 - ((dest >> 22) & 1)) << 22) & 0x3FFFFFFF)
45 					| (dest & 0x3FFFFF)
46 					| 0x40000000;
47 
48 			buffer[i + 0] = (uint8_t)(dest >> 24);
49 			buffer[i + 1] = (uint8_t)(dest >> 16);
50 			buffer[i + 2] = (uint8_t)(dest >> 8);
51 			buffer[i + 3] = (uint8_t)(dest);
52 		}
53 	}
54 
55 	return i;
56 }
57 
58 
59 static lzma_ret
60 sparc_coder_init(lzma_next_coder *next, const lzma_allocator *allocator,
61 		const lzma_filter_info *filters, bool is_encoder)
62 {
63 	return lzma_simple_coder_init(next, allocator, filters,
64 			&sparc_code, 0, 4, 4, is_encoder);
65 }
66 
67 
68 extern lzma_ret
69 lzma_simple_sparc_encoder_init(lzma_next_coder *next,
70 		const lzma_allocator *allocator,
71 		const lzma_filter_info *filters)
72 {
73 	return sparc_coder_init(next, allocator, filters, true);
74 }
75 
76 
77 extern lzma_ret
78 lzma_simple_sparc_decoder_init(lzma_next_coder *next,
79 		const lzma_allocator *allocator,
80 		const lzma_filter_info *filters)
81 {
82 	return sparc_coder_init(next, allocator, filters, false);
83 }
84