1 files changed, 64 insertions, 0 deletions
diff --git a/modules/brotli/common/constants.h b/modules/brotli/common/constants.h
new file mode 100644
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+++ b/modules/brotli/common/constants.h
@@ -0,0 +1,64 @@
+/* Copyright 2016 Google Inc. All Rights Reserved.
+
+   Distributed under MIT license.
+   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+#ifndef BROTLI_COMMON_CONSTANTS_H_
+#define BROTLI_COMMON_CONSTANTS_H_
+
+/* Specification: 7.3. Encoding of the context map */
+#define BROTLI_CONTEXT_MAP_MAX_RLE 16
+
+/* Specification: 2. Compressed representation overview */
+#define BROTLI_MAX_NUMBER_OF_BLOCK_TYPES 256
+
+/* Specification: 3.3. Alphabet sizes: insert-and-copy length */
+#define BROTLI_NUM_LITERAL_SYMBOLS 256
+#define BROTLI_NUM_COMMAND_SYMBOLS 704
+#define BROTLI_NUM_BLOCK_LEN_SYMBOLS 26
+#define BROTLI_MAX_CONTEXT_MAP_SYMBOLS (BROTLI_MAX_NUMBER_OF_BLOCK_TYPES + \
+                                        BROTLI_CONTEXT_MAP_MAX_RLE)
+#define BROTLI_MAX_BLOCK_TYPE_SYMBOLS (BROTLI_MAX_NUMBER_OF_BLOCK_TYPES + 2)
+
+/* Specification: 3.5. Complex prefix codes */
+#define BROTLI_REPEAT_PREVIOUS_CODE_LENGTH 16
+#define BROTLI_REPEAT_ZERO_CODE_LENGTH 17
+#define BROTLI_CODE_LENGTH_CODES (BROTLI_REPEAT_ZERO_CODE_LENGTH + 1)
+/* "code length of 8 is repeated" */
+#define BROTLI_INITIAL_REPEATED_CODE_LENGTH 8
+
+/* "Large Window Brotli" */
+#define BROTLI_LARGE_MAX_DISTANCE_BITS 62U
+#define BROTLI_LARGE_MIN_WBITS 10
+#define BROTLI_LARGE_MAX_WBITS 30
+
+/* Specification: 4. Encoding of distances */
+#define BROTLI_NUM_DISTANCE_SHORT_CODES 16
+#define BROTLI_MAX_NPOSTFIX 3
+#define BROTLI_MAX_NDIRECT 120
+#define BROTLI_MAX_DISTANCE_BITS 24U
+#define BROTLI_DISTANCE_ALPHABET_SIZE(NPOSTFIX, NDIRECT, MAXNBITS) ( \
+    BROTLI_NUM_DISTANCE_SHORT_CODES + (NDIRECT) +                    \
+    ((MAXNBITS) << ((NPOSTFIX) + 1)))
+/* BROTLI_NUM_DISTANCE_SYMBOLS == 1128 */
+#define BROTLI_NUM_DISTANCE_SYMBOLS \
+    BROTLI_DISTANCE_ALPHABET_SIZE(  \
+        BROTLI_MAX_NDIRECT, BROTLI_MAX_NPOSTFIX, BROTLI_LARGE_MAX_DISTANCE_BITS)
+#define BROTLI_MAX_DISTANCE 0x3FFFFFC
+#define BROTLI_MAX_ALLOWED_DISTANCE 0x7FFFFFFC
+
+/* 7.1. Context modes and context ID lookup for literals */
+/* "context IDs for literals are in the range of 0..63" */
+#define BROTLI_LITERAL_CONTEXT_BITS 6
+
+/* 7.2. Context ID for distances */
+#define BROTLI_DISTANCE_CONTEXT_BITS 2
+
+/* 9.1. Format of the Stream Header */
+/* Number of slack bytes for window size. Don't confuse
+   with BROTLI_NUM_DISTANCE_SHORT_CODES. */
+#define BROTLI_WINDOW_GAP 16
+#define BROTLI_MAX_BACKWARD_LIMIT(W) (((size_t)1 << (W)) - BROTLI_WINDOW_GAP)
+
+#endif  /* BROTLI_COMMON_CONSTANTS_H_ */