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Diffstat (limited to 'c/common/dictionary.h')
-rw-r--r-- | c/common/dictionary.h | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/c/common/dictionary.h b/c/common/dictionary.h new file mode 100644 index 0000000..fc47c1e --- /dev/null +++ b/c/common/dictionary.h @@ -0,0 +1,50 @@ +/* Copyright 2013 Google Inc. All Rights Reserved. + + Distributed under MIT license. + See file LICENSE for detail or copy at https://opensource.org/licenses/MIT +*/ + +/* Collection of static dictionary words. */ + +#ifndef BROTLI_COMMON_DICTIONARY_H_ +#define BROTLI_COMMON_DICTIONARY_H_ + +#include <brotli/port.h> +#include <brotli/types.h> + +#if defined(__cplusplus) || defined(c_plusplus) +extern "C" { +#endif + +typedef struct BrotliDictionary { + /** + * Number of bits to encode index of dictionary word in a bucket. + * + * Specification: Appendix A. Static Dictionary Data + * + * Words in a dictionary are bucketed by length. + * @c 0 means that there are no words of a given length. + * Dictionary consists of words with length of [4..24] bytes. + * Values at [0..3] and [25..31] indices should not be addressed. + */ + uint8_t size_bits_by_length[32]; + + /* assert(offset[i + 1] == offset[i] + (bits[i] ? (i << bits[i]) : 0)) */ + uint32_t offsets_by_length[32]; + + /* Data array is not bound, and should obey to size_bits_by_length values. + Specified size matches default (RFC 7932) dictionary. */ + /* assert(sizeof(data) == offsets_by_length[31]) */ + uint8_t data[122784]; +} BrotliDictionary; + +BROTLI_COMMON_API extern const BrotliDictionary* BrotliGetDictionary(void); + +#define BROTLI_MIN_DICTIONARY_WORD_LENGTH 4 +#define BROTLI_MAX_DICTIONARY_WORD_LENGTH 24 + +#if defined(__cplusplus) || defined(c_plusplus) +} /* extern "C" */ +#endif + +#endif /* BROTLI_COMMON_DICTIONARY_H_ */ |