MdeModulePkg/BrotliCustomDecompressLib: Make brotli a submodule

[mirror_edk2.git] / BaseTools / Source / C / BrotliCompress / enc / prefix.h

/* Copyright 2013 Google Inc. All Rights Reserved.\r
\r
   Distributed under MIT license.\r
   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT\r
*/\r
\r
/* Functions for encoding of integers into prefix codes the amount of extra\r
   bits, and the actual values of the extra bits. */\r
\r
#ifndef BROTLI_ENC_PREFIX_H_\r
#define BROTLI_ENC_PREFIX_H_\r
\r
#include "../common/constants.h"\r
#include "../common/platform.h"\r
#include <brotli/types.h>\r
#include "./fast_log.h"\r
\r
#if defined(__cplusplus) || defined(c_plusplus)\r
extern "C" {\r
#endif\r
\r
/* Here distance_code is an intermediate code, i.e. one of the special codes or\r
   the actual distance increased by BROTLI_NUM_DISTANCE_SHORT_CODES - 1. */\r
static BROTLI_INLINE void PrefixEncodeCopyDistance(size_t distance_code,\r
                                                   size_t num_direct_codes,\r
                                                   size_t postfix_bits,\r
                                                   uint16_t* code,\r
                                                   uint32_t* extra_bits) {\r
  if (distance_code < BROTLI_NUM_DISTANCE_SHORT_CODES + num_direct_codes) {\r
    *code = (uint16_t)distance_code;\r
    *extra_bits = 0;\r
    return;\r
  } else {\r
    size_t dist = ((size_t)1 << (postfix_bits + 2u)) +\r
        (distance_code - BROTLI_NUM_DISTANCE_SHORT_CODES - num_direct_codes);\r
    size_t bucket = Log2FloorNonZero(dist) - 1;\r
    size_t postfix_mask = (1u << postfix_bits) - 1;\r
    size_t postfix = dist & postfix_mask;\r
    size_t prefix = (dist >> bucket) & 1;\r
    size_t offset = (2 + prefix) << bucket;\r
    size_t nbits = bucket - postfix_bits;\r
    *code = (uint16_t)((nbits << 10) |\r
        (BROTLI_NUM_DISTANCE_SHORT_CODES + num_direct_codes +\r
         ((2 * (nbits - 1) + prefix) << postfix_bits) + postfix));\r
    *extra_bits = (uint32_t)((dist - offset) >> postfix_bits);\r
  }\r
}\r
\r
#if defined(__cplusplus) || defined(c_plusplus)\r
}  /* extern "C" */\r
#endif\r
\r
#endif  /* BROTLI_ENC_PREFIX_H_ */\r