prefix.c - mozsearch

Enable keyboard shortcuts

/* Copyright 2025 Google Inc. All Rights Reserved.

   Distributed under MIT license.

   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT

*/

#include "prefix.h"

#include "../common/platform.h"  /* IWYU pragma: keep */

#include "../common/static_init.h"

#if (BROTLI_STATIC_INIT != BROTLI_STATIC_INIT_NONE)

#include "../common/constants.h"

#endif

#if defined(__cplusplus) || defined(c_plusplus)

extern "C" {

#endif

#if (BROTLI_STATIC_INIT == BROTLI_STATIC_INIT_NONE)

/* Embed kCmdLut. */

#include "prefix_inc.h"

#else

BROTLI_COLD BROTLI_BOOL BrotliDecoderInitCmdLut(CmdLutElement* items) {

  static const uint8_t kInsertLengthExtraBits[24] = {

      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01, 0x02, 0x02, 0x03, 0x03,

      0x04, 0x04, 0x05, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A, 0x0C, 0x0E, 0x18};

  static const uint8_t kCopyLengthExtraBits[24] = {

      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01, 0x02, 0x02,

      0x03, 0x03, 0x04, 0x04, 0x05, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A, 0x18};

  static const uint8_t kCellPos[11] = {0, 1, 0, 1, 8, 9, 2, 16, 10, 17, 18};

  uint16_t insert_length_offsets[24];

  uint16_t copy_length_offsets[24];

  insert_length_offsets[0] = 0;

  copy_length_offsets[0] = 2;

  for (size_t i = 0; i < 23; ++i) {

    insert_length_offsets[i + 1] =

        insert_length_offsets[i] + (uint16_t)(1u << kInsertLengthExtraBits[i]);

    copy_length_offsets[i + 1] =

        copy_length_offsets[i] + (uint16_t)(1u << kCopyLengthExtraBits[i]);

  for (size_t symbol = 0; symbol < BROTLI_NUM_COMMAND_SYMBOLS; ++symbol) {

    CmdLutElement* item = items + symbol;

    const size_t cell_idx = symbol >> 6;

    const size_t cell_pos = kCellPos[cell_idx];

    const size_t copy_code = ((cell_pos << 3) & 0x18) + (symbol & 0x7);

    const uint16_t copy_len_offset = copy_length_offsets[copy_code];

    const size_t insert_code = (cell_pos & 0x18) + ((symbol >> 3) & 0x7);

    item->copy_len_extra_bits = kCopyLengthExtraBits[copy_code];

    item->context = (copy_len_offset > 4) ? 3 : ((uint8_t)copy_len_offset - 2);

    item->copy_len_offset = copy_len_offset;

    item->distance_code = (cell_idx >= 2) ? -1 : 0;

    item->insert_len_extra_bits = kInsertLengthExtraBits[insert_code];

    item->insert_len_offset = insert_length_offsets[insert_code];

  return BROTLI_TRUE;

BROTLI_MODEL("small")

CmdLutElement kCmdLut[BROTLI_NUM_COMMAND_SYMBOLS];

#endif  /* BROTLI_STATIC_INIT */

#if defined(__cplusplus) || defined(c_plusplus)

}  /* extern "C" */

#endif