| /* Copyright 2013 Google Inc. All Rights Reserved. |
| |
| Licensed under the Apache License, Version 2.0 (the "License"); |
| you may not use this file except in compliance with the License. |
| You may obtain a copy of the License at |
| |
| http://www.apache.org/licenses/LICENSE-2.0 |
| |
| Unless required by applicable law or agreed to in writing, software |
| distributed under the License is distributed on an "AS IS" BASIS, |
| WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| See the License for the specific language governing permissions and |
| limitations under the License. |
| */ |
| |
| /* Bit reading helpers */ |
| |
| #include <stdlib.h> |
| |
| #include "./bit_reader.h" |
| #include "./port.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; |
| } |
| |
| int 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 aligment. */ |
| if (!BROTLI_ALIGNED_READ) { |
| aligned_read_mask = 0; |
| } |
| if (BrotliGetAvailableBits(br) == 0) { |
| if (!BrotliPullByte(br)) { |
| return 0; |
| } |
| } |
| |
| 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 1; |
| } |
| } |
| return 1; |
| } |
| |
| #if defined(__cplusplus) || defined(c_plusplus) |
| } /* extern "C" */ |
| #endif |