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Diffstat (limited to 'misc/ttf2woff/zopfli/symbols.h')
-rw-r--r-- | misc/ttf2woff/zopfli/symbols.h | 239 |
1 files changed, 239 insertions, 0 deletions
diff --git a/misc/ttf2woff/zopfli/symbols.h b/misc/ttf2woff/zopfli/symbols.h new file mode 100644 index 000000000..b49df06c7 --- /dev/null +++ b/misc/ttf2woff/zopfli/symbols.h @@ -0,0 +1,239 @@ +/* +Copyright 2016 Google Inc. All Rights Reserved. + +Licensed under the Apache License, Version 2.0 (the "License"); +you may not use this file except in compliance with the License. +You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + +Unless required by applicable law or agreed to in writing, software +distributed under the License is distributed on an "AS IS" BASIS, +WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +See the License for the specific language governing permissions and +limitations under the License. + +Author: lode.vandevenne@gmail.com (Lode Vandevenne) +Author: jyrki.alakuijala@gmail.com (Jyrki Alakuijala) +*/ + +/* +Utilities for using the lz77 symbols of the deflate spec. +*/ + +#ifndef ZOPFLI_SYMBOLS_H_ +#define ZOPFLI_SYMBOLS_H_ + +/* __has_builtin available in clang */ +#ifdef __has_builtin +# if __has_builtin(__builtin_clz) +# define ZOPFLI_HAS_BUILTIN_CLZ +# endif +/* __builtin_clz available beginning with GCC 3.4 */ +#elif __GNUC__ * 100 + __GNUC_MINOR__ >= 304 +# define ZOPFLI_HAS_BUILTIN_CLZ +#endif + +/* Gets the amount of extra bits for the given dist, cfr. the DEFLATE spec. */ +static int ZopfliGetDistExtraBits(int dist) { +#ifdef ZOPFLI_HAS_BUILTIN_CLZ + if (dist < 5) return 0; + return (31 ^ __builtin_clz(dist - 1)) - 1; /* log2(dist - 1) - 1 */ +#else + if (dist < 5) return 0; + else if (dist < 9) return 1; + else if (dist < 17) return 2; + else if (dist < 33) return 3; + else if (dist < 65) return 4; + else if (dist < 129) return 5; + else if (dist < 257) return 6; + else if (dist < 513) return 7; + else if (dist < 1025) return 8; + else if (dist < 2049) return 9; + else if (dist < 4097) return 10; + else if (dist < 8193) return 11; + else if (dist < 16385) return 12; + else return 13; +#endif +} + +/* Gets value of the extra bits for the given dist, cfr. the DEFLATE spec. */ +static int ZopfliGetDistExtraBitsValue(int dist) { +#ifdef ZOPFLI_HAS_BUILTIN_CLZ + if (dist < 5) { + return 0; + } else { + int l = 31 ^ __builtin_clz(dist - 1); /* log2(dist - 1) */ + return (dist - (1 + (1 << l))) & ((1 << (l - 1)) - 1); + } +#else + if (dist < 5) return 0; + else if (dist < 9) return (dist - 5) & 1; + else if (dist < 17) return (dist - 9) & 3; + else if (dist < 33) return (dist - 17) & 7; + else if (dist < 65) return (dist - 33) & 15; + else if (dist < 129) return (dist - 65) & 31; + else if (dist < 257) return (dist - 129) & 63; + else if (dist < 513) return (dist - 257) & 127; + else if (dist < 1025) return (dist - 513) & 255; + else if (dist < 2049) return (dist - 1025) & 511; + else if (dist < 4097) return (dist - 2049) & 1023; + else if (dist < 8193) return (dist - 4097) & 2047; + else if (dist < 16385) return (dist - 8193) & 4095; + else return (dist - 16385) & 8191; +#endif +} + +/* Gets the symbol for the given dist, cfr. the DEFLATE spec. */ +static int ZopfliGetDistSymbol(int dist) { +#ifdef ZOPFLI_HAS_BUILTIN_CLZ + if (dist < 5) { + return dist - 1; + } else { + int l = (31 ^ __builtin_clz(dist - 1)); /* log2(dist - 1) */ + int r = ((dist - 1) >> (l - 1)) & 1; + return l * 2 + r; + } +#else + if (dist < 193) { + if (dist < 13) { /* dist 0..13. */ + if (dist < 5) return dist - 1; + else if (dist < 7) return 4; + else if (dist < 9) return 5; + else return 6; + } else { /* dist 13..193. */ + if (dist < 17) return 7; + else if (dist < 25) return 8; + else if (dist < 33) return 9; + else if (dist < 49) return 10; + else if (dist < 65) return 11; + else if (dist < 97) return 12; + else if (dist < 129) return 13; + else return 14; + } + } else { + if (dist < 2049) { /* dist 193..2049. */ + if (dist < 257) return 15; + else if (dist < 385) return 16; + else if (dist < 513) return 17; + else if (dist < 769) return 18; + else if (dist < 1025) return 19; + else if (dist < 1537) return 20; + else return 21; + } else { /* dist 2049..32768. */ + if (dist < 3073) return 22; + else if (dist < 4097) return 23; + else if (dist < 6145) return 24; + else if (dist < 8193) return 25; + else if (dist < 12289) return 26; + else if (dist < 16385) return 27; + else if (dist < 24577) return 28; + else return 29; + } + } +#endif +} + +/* Gets the amount of extra bits for the given length, cfr. the DEFLATE spec. */ +static int ZopfliGetLengthExtraBits(int l) { + static const int table[259] = { + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, + 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, + 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, + 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, + 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, + 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, + 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, + 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, + 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, + 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, + 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, + 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, + 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, + 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, + 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, + 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 0 + }; + return table[l]; +} + +/* Gets value of the extra bits for the given length, cfr. the DEFLATE spec. */ +static int ZopfliGetLengthExtraBitsValue(int l) { + static const int table[259] = { + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 2, 3, 0, + 1, 2, 3, 0, 1, 2, 3, 0, 1, 2, 3, 0, 1, 2, 3, 4, 5, 6, 7, 0, 1, 2, 3, 4, 5, + 6, 7, 0, 1, 2, 3, 4, 5, 6, 7, 0, 1, 2, 3, 4, 5, 6, 7, 0, 1, 2, 3, 4, 5, 6, + 7, 8, 9, 10, 11, 12, 13, 14, 15, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, + 13, 14, 15, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 0, 1, 2, + 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, + 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, + 29, 30, 31, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, + 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 0, 1, 2, 3, 4, 5, 6, + 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, + 27, 28, 29, 30, 31, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, + 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 0 + }; + return table[l]; +} + +/* +Gets the symbol for the given length, cfr. the DEFLATE spec. +Returns the symbol in the range [257-285] (inclusive) +*/ +static int ZopfliGetLengthSymbol(int l) { + static const int table[259] = { + 0, 0, 0, 257, 258, 259, 260, 261, 262, 263, 264, + 265, 265, 266, 266, 267, 267, 268, 268, + 269, 269, 269, 269, 270, 270, 270, 270, + 271, 271, 271, 271, 272, 272, 272, 272, + 273, 273, 273, 273, 273, 273, 273, 273, + 274, 274, 274, 274, 274, 274, 274, 274, + 275, 275, 275, 275, 275, 275, 275, 275, + 276, 276, 276, 276, 276, 276, 276, 276, + 277, 277, 277, 277, 277, 277, 277, 277, + 277, 277, 277, 277, 277, 277, 277, 277, + 278, 278, 278, 278, 278, 278, 278, 278, + 278, 278, 278, 278, 278, 278, 278, 278, + 279, 279, 279, 279, 279, 279, 279, 279, + 279, 279, 279, 279, 279, 279, 279, 279, + 280, 280, 280, 280, 280, 280, 280, 280, + 280, 280, 280, 280, 280, 280, 280, 280, + 281, 281, 281, 281, 281, 281, 281, 281, + 281, 281, 281, 281, 281, 281, 281, 281, + 281, 281, 281, 281, 281, 281, 281, 281, + 281, 281, 281, 281, 281, 281, 281, 281, + 282, 282, 282, 282, 282, 282, 282, 282, + 282, 282, 282, 282, 282, 282, 282, 282, + 282, 282, 282, 282, 282, 282, 282, 282, + 282, 282, 282, 282, 282, 282, 282, 282, + 283, 283, 283, 283, 283, 283, 283, 283, + 283, 283, 283, 283, 283, 283, 283, 283, + 283, 283, 283, 283, 283, 283, 283, 283, + 283, 283, 283, 283, 283, 283, 283, 283, + 284, 284, 284, 284, 284, 284, 284, 284, + 284, 284, 284, 284, 284, 284, 284, 284, + 284, 284, 284, 284, 284, 284, 284, 284, + 284, 284, 284, 284, 284, 284, 284, 285 + }; + return table[l]; +} + +/* Gets the amount of extra bits for the given length symbol. */ +static int ZopfliGetLengthSymbolExtraBits(int s) { + static const int table[29] = { + 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, + 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0 + }; + return table[s - 257]; +} + +/* Gets the amount of extra bits for the given distance symbol. */ +static int ZopfliGetDistSymbolExtraBits(int s) { + static const int table[30] = { + 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, + 9, 9, 10, 10, 11, 11, 12, 12, 13, 13 + }; + return table[s]; +} + +#endif /* ZOPFLI_SYMBOLS_H_ */ |