1 | /* |
1 | /* |
2 | * Copyright (c) 2000-2008 Marc Alexander Lehmann <schmorp@schmorp.de> |
2 | * Copyright (c) 2000-2009 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, |
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87 | #define expect_true(expr) expect ((expr) != 0, 1) |
87 | #define expect_true(expr) expect ((expr) != 0, 1) |
88 | |
88 | |
89 | /* |
89 | /* |
90 | * compressed format |
90 | * compressed format |
91 | * |
91 | * |
92 | * 000LLLLL <L+1> ; literal |
92 | * 000LLLLL <L+1> ; literal, L+1=1..33 octets |
93 | * LLLooooo oooooooo ; backref L |
93 | * LLLooooo oooooooo ; backref L+1=1..7 octets, o+1=1..4096 offset |
94 | * 111ooooo LLLLLLLL oooooooo ; backref L+7 |
94 | * 111ooooo LLLLLLLL oooooooo ; backref L+8 octets, o+1=1..4096 offset |
95 | * |
95 | * |
96 | */ |
96 | */ |
97 | |
97 | |
98 | unsigned int |
98 | unsigned int |
99 | lzf_compress (const void *const in_data, unsigned int in_len, |
99 | lzf_compress (const void *const in_data, unsigned int in_len, |
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168 | /* match found at *ref++ */ |
168 | /* match found at *ref++ */ |
169 | unsigned int len = 2; |
169 | unsigned int len = 2; |
170 | unsigned int maxlen = in_end - ip - len; |
170 | unsigned int maxlen = in_end - ip - len; |
171 | maxlen = maxlen > MAX_REF ? MAX_REF : maxlen; |
171 | maxlen = maxlen > MAX_REF ? MAX_REF : maxlen; |
172 | |
172 | |
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173 | if (expect_false (op + 3 + 1 >= out_end)) /* first a faster conservative test */ |
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174 | if (op - !lit + 3 + 1 >= out_end) /* second the exact but rare test */ |
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175 | return 0; |
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176 | |
173 | op [- lit - 1] = lit - 1; /* stop run */ |
177 | op [- lit - 1] = lit - 1; /* stop run */ |
174 | op -= !lit; /* undo run if length is zero */ |
178 | op -= !lit; /* undo run if length is zero */ |
175 | |
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176 | if (expect_false (op + 3 + 1 >= out_end)) |
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177 | return 0; |
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178 | |
179 | |
179 | for (;;) |
180 | for (;;) |
180 | { |
181 | { |
181 | if (expect_true (maxlen > 16)) |
182 | if (expect_true (maxlen > 16)) |
182 | { |
183 | { |