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23934731f5
* More clear/safe "copy" command stage implementation
* Enable unaligned memory access only on whitelisted CPUs
* Remove unused streams.{c|h}
* Add "default" to all switches
* Fix includes
* Fix spacing everywhere
49 lines
1.2 KiB
C
49 lines
1.2 KiB
C
/* Copyright 2013 Google Inc. All Rights Reserved.
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Distributed under MIT license.
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See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
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*/
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/* Bit reading helpers */
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#include "./bit_reader.h"
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#include "./port.h"
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#include "./types.h"
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#if defined(__cplusplus) || defined(c_plusplus)
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extern "C" {
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#endif
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void BrotliInitBitReader(BrotliBitReader* const br) {
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br->val_ = 0;
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br->bit_pos_ = sizeof(br->val_) << 3;
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}
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int BrotliWarmupBitReader(BrotliBitReader* const br) {
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size_t aligned_read_mask = (sizeof(br->val_) >> 1) - 1;
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/* Fixing alignment after unaligned BrotliFillWindow would result accumulator
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overflow. If unalignment is caused by BrotliSafeReadBits, then there is
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enough space in accumulator to fix aligment. */
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if (!BROTLI_ALIGNED_READ) {
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aligned_read_mask = 0;
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}
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if (BrotliGetAvailableBits(br) == 0) {
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if (!BrotliPullByte(br)) {
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return 0;
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}
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}
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while ((((size_t)br->next_in) & aligned_read_mask) != 0) {
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if (!BrotliPullByte(br)) {
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/* If we consumed all the input, we don't care about the alignment. */
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return 1;
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}
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}
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return 1;
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}
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#if defined(__cplusplus) || defined(c_plusplus)
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} /* extern "C" */
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#endif
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