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+/* 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];
+
+ /* assert(data_size == offsets_by_length[31]) */
+ size_t data_size;
+
+ /* Data array is not bound, and should obey to size_bits_by_length values.
+ Specified size matches default (RFC 7932) dictionary. Its size is
+ defined by data_size */
+ const uint8_t* data;
+} BrotliDictionary;
+
+BROTLI_COMMON_API const BrotliDictionary* BrotliGetDictionary(void);
+
+/**
+ * Sets dictionary data.
+ *
+ * When dictionary data is already set / present, this method is no-op.
+ *
+ * Dictionary data MUST be provided before BrotliGetDictionary is invoked.
+ * This method is used ONLY in multi-client environment (e.g. C + Java),
+ * to reduce storage by sharing single dictionary between implementations.
+ */
+BROTLI_COMMON_API void BrotliSetDictionaryData(const uint8_t* data);
+
+#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_ */