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-rw-r--r--modules/brotli/dec/bit_reader.c48
1 files changed, 48 insertions, 0 deletions
diff --git a/modules/brotli/dec/bit_reader.c b/modules/brotli/dec/bit_reader.c
new file mode 100644
index 000000000..cde90af56
--- /dev/null
+++ b/modules/brotli/dec/bit_reader.c
@@ -0,0 +1,48 @@
+/* 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 "./port.h"
+#include "./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;
+}
+
+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