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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