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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
*/ 
 
/* Bit reading helpers */ 
 
#include "./bit_reader.h"
 
#include "../common/platform.h"
#include <brotli/types.h>
 
#if defined(__cplusplus) || defined(c_plusplus) 
extern "C" { 
#endif 
 
void BrotliInitBitReader(BrotliBitReader* const br) {
  br->val_ = 0; 
  br->bit_pos_ = sizeof(br->val_) << 3; 
} 
 
BROTLI_BOOL BrotliWarmupBitReader(BrotliBitReader* const br) {
  size_t aligned_read_mask = (sizeof(br->val_) >> 1) - 1;
  /* Fixing alignment after unaligned BrotliFillWindow would result accumulator
     overflow. If unalignment is caused by BrotliSafeReadBits, then there is
     enough space in accumulator to fix alignment. */
  if (!BROTLI_ALIGNED_READ) {
    aligned_read_mask = 0;
  }
  if (BrotliGetAvailableBits(br) == 0) {
    if (!BrotliPullByte(br)) {
      return BROTLI_FALSE;
    } 
  } 

  while ((((size_t)br->next_in) & aligned_read_mask) != 0) {
    if (!BrotliPullByte(br)) {
      /* If we consumed all the input, we don't care about the alignment. */
      return BROTLI_TRUE;
    }
  }
  return BROTLI_TRUE;
} 
 
#if defined(__cplusplus) || defined(c_plusplus) 
}  /* extern "C" */
#endif