1 | /* |
1 | /* |
2 | * Copyright (c) 2000-2010,2012 Marc Alexander Lehmann <schmorp@schmorp.de> |
2 | * Copyright (c) 2000-2010,2012 Marc Alexander Lehmann <schmorp@schmorp.de> |
3 | * |
3 | * |
4 | * Redistribution and use in source and binary forms, with or without modifica- |
4 | * Redistribution and use in source and binary forms, with or without modifica- |
5 | * tion, are permitted provided that the following conditions are met: |
5 | * tion, are permitted provided that the following conditions are met: |
6 | * |
6 | * |
7 | * 1. Redistributions of source code must retain the above copyright notice, |
7 | * 1. Redistributions of source code must retain the above copyright notice, |
8 | * this list of conditions and the following disclaimer. |
8 | * this list of conditions and the following disclaimer. |
9 | * |
9 | * |
10 | * 2. Redistributions in binary form must reproduce the above copyright |
10 | * 2. Redistributions in binary form must reproduce the above copyright |
11 | * notice, this list of conditions and the following disclaimer in the |
11 | * notice, this list of conditions and the following disclaimer in the |
12 | * documentation and/or other materials provided with the distribution. |
12 | * documentation and/or other materials provided with the distribution. |
13 | * |
13 | * |
14 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED |
14 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED |
15 | * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER- |
15 | * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER- |
16 | * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO |
16 | * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO |
17 | * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE- |
17 | * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE- |
18 | * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
18 | * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
… | |
… | |
69 | # define FRST(p) (p[0] << 5) ^ p[1] |
69 | # define FRST(p) (p[0] << 5) ^ p[1] |
70 | # define NEXT(v,p) ((v) << 5) ^ p[2] |
70 | # define NEXT(v,p) ((v) << 5) ^ p[2] |
71 | # define IDX(h) ((h) & (HSIZE - 1)) |
71 | # define IDX(h) ((h) & (HSIZE - 1)) |
72 | #endif |
72 | #endif |
73 | |
73 | |
74 | #define MAX_LIT (1 << 5) |
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75 | #define MAX_OFF (1 << 13) |
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76 | #define MAX_REF ((1 << 8) + (1 << 3)) |
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77 | |
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78 | #if __GNUC__ >= 3 |
74 | #if __GNUC__ >= 3 |
79 | # define expect(expr,value) __builtin_expect ((expr),(value)) |
75 | # define expect(expr,value) __builtin_expect ((expr),(value)) |
80 | # define inline inline |
76 | # define inline inline |
81 | #else |
77 | #else |
82 | # define expect(expr,value) (expr) |
78 | # define expect(expr,value) (expr) |
… | |
… | |
119 | * and fails to support both assumptions is windows 64 bit, we make a |
115 | * and fails to support both assumptions is windows 64 bit, we make a |
120 | * special workaround for it. |
116 | * special workaround for it. |
121 | */ |
117 | */ |
122 | #if defined (_WIN32) && defined (_M_X64) |
118 | #if defined (_WIN32) && defined (_M_X64) |
123 | /* workaround for missing POSIX compliance */ |
119 | /* workaround for missing POSIX compliance */ |
124 | #if #if __GNUC__ |
120 | #if __GNUC__ |
125 | unsigned long long off; |
121 | unsigned long long off; |
126 | #else |
122 | #else |
127 | unsigned __int64 off; |
123 | unsigned __int64 off; |
128 | #endif |
124 | #endif |
129 | #else |
125 | #else |
… | |
… | |
134 | |
130 | |
135 | if (!in_len || !out_len) |
131 | if (!in_len || !out_len) |
136 | return 0; |
132 | return 0; |
137 | |
133 | |
138 | #if INIT_HTAB |
134 | #if INIT_HTAB |
139 | memset (htab, 0, sizeof (htab)); |
135 | memset (htab, 0, sizeof (LZF_STATE)); |
140 | #endif |
136 | #endif |
141 | |
137 | |
142 | lit = 0; op++; /* start run */ |
138 | lit = 0; op++; /* start run */ |
143 | |
139 | |
144 | hval = FRST (ip); |
140 | hval = FRST (ip); |
… | |
… | |
152 | |
148 | |
153 | if (1 |
149 | if (1 |
154 | #if INIT_HTAB |
150 | #if INIT_HTAB |
155 | && ref < ip /* the next test will actually take care of this, but this is faster */ |
151 | && ref < ip /* the next test will actually take care of this, but this is faster */ |
156 | #endif |
152 | #endif |
157 | && (off = ip - ref - 1) < MAX_OFF |
153 | && (off = ip - ref - 1) < LZF_MAX_OFF |
158 | && ref > (u8 *)in_data |
154 | && ref > (u8 *)in_data |
159 | && ref[2] == ip[2] |
155 | && ref[2] == ip[2] |
160 | #if STRICT_ALIGN |
156 | #if STRICT_ALIGN |
161 | && ((ref[1] << 8) | ref[0]) == ((ip[1] << 8) | ip[0]) |
157 | && ((ref[1] << 8) | ref[0]) == ((ip[1] << 8) | ip[0]) |
162 | #else |
158 | #else |
… | |
… | |
165 | ) |
161 | ) |
166 | { |
162 | { |
167 | /* match found at *ref++ */ |
163 | /* match found at *ref++ */ |
168 | unsigned int len = 2; |
164 | unsigned int len = 2; |
169 | unsigned int maxlen = in_end - ip - len; |
165 | unsigned int maxlen = in_end - ip - len; |
170 | maxlen = maxlen > MAX_REF ? MAX_REF : maxlen; |
166 | maxlen = maxlen > LZF_MAX_REF ? LZF_MAX_REF : maxlen; |
171 | |
167 | |
172 | if (expect_false (op + 3 + 1 >= out_end)) /* first a faster conservative test */ |
168 | if (expect_false (op + 3 + 1 >= out_end)) /* first a faster conservative test */ |
173 | if (op - !lit + 3 + 1 >= out_end) /* second the exact but rare test */ |
169 | if (op - !lit + 3 + 1 >= out_end) /* second the exact but rare test */ |
174 | return 0; |
170 | return 0; |
175 | |
171 | |
… | |
… | |
264 | if (expect_false (op >= out_end)) |
260 | if (expect_false (op >= out_end)) |
265 | return 0; |
261 | return 0; |
266 | |
262 | |
267 | lit++; *op++ = *ip++; |
263 | lit++; *op++ = *ip++; |
268 | |
264 | |
269 | if (expect_false (lit == MAX_LIT)) |
265 | if (expect_false (lit == LZF_MAX_LIT)) |
270 | { |
266 | { |
271 | op [- lit - 1] = lit - 1; /* stop run */ |
267 | op [- lit - 1] = lit - 1; /* stop run */ |
272 | lit = 0; op++; /* start run */ |
268 | lit = 0; op++; /* start run */ |
273 | } |
269 | } |
274 | } |
270 | } |
… | |
… | |
279 | |
275 | |
280 | while (ip < in_end) |
276 | while (ip < in_end) |
281 | { |
277 | { |
282 | lit++; *op++ = *ip++; |
278 | lit++; *op++ = *ip++; |
283 | |
279 | |
284 | if (expect_false (lit == MAX_LIT)) |
280 | if (expect_false (lit == LZF_MAX_LIT)) |
285 | { |
281 | { |
286 | op [- lit - 1] = lit - 1; /* stop run */ |
282 | op [- lit - 1] = lit - 1; /* stop run */ |
287 | lit = 0; op++; /* start run */ |
283 | lit = 0; op++; /* start run */ |
288 | } |
284 | } |
289 | } |
285 | } |