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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-30 02:50:01 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-30 02:50:01 +0000
commit91275eb478ceb58083426099b6da3f4c7e189f19 (patch)
tree260f7d2fa77408b38c5cea96b320b9b0b6713ff2 /debian/vendor-h2o/deps/brotli/enc/ringbuffer.h
parentMerging upstream version 1.9.4. (diff)
downloaddnsdist-91275eb478ceb58083426099b6da3f4c7e189f19.tar.xz
dnsdist-91275eb478ceb58083426099b6da3f4c7e189f19.zip
Merging debian version 1.9.4-1.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'debian/vendor-h2o/deps/brotli/enc/ringbuffer.h')
-rw-r--r--debian/vendor-h2o/deps/brotli/enc/ringbuffer.h114
1 files changed, 0 insertions, 114 deletions
diff --git a/debian/vendor-h2o/deps/brotli/enc/ringbuffer.h b/debian/vendor-h2o/deps/brotli/enc/ringbuffer.h
deleted file mode 100644
index d523792..0000000
--- a/debian/vendor-h2o/deps/brotli/enc/ringbuffer.h
+++ /dev/null
@@ -1,114 +0,0 @@
-/* Copyright 2013 Google Inc. All Rights Reserved.
-
- Distributed under MIT license.
- See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
-*/
-
-// Sliding window over the input data.
-
-#ifndef BROTLI_ENC_RINGBUFFER_H_
-#define BROTLI_ENC_RINGBUFFER_H_
-
-
-#include "./port.h"
-#include "./types.h"
-
-namespace brotli {
-
-// A RingBuffer(window_bits, tail_bits) contains `1 << window_bits' bytes of
-// data in a circular manner: writing a byte writes it to:
-// `position() % (1 << window_bits)'.
-// For convenience, the RingBuffer array contains another copy of the
-// first `1 << tail_bits' bytes:
-// buffer_[i] == buffer_[i + (1 << window_bits)], if i < (1 << tail_bits),
-// and another copy of the last two bytes:
-// buffer_[-1] == buffer_[(1 << window_bits) - 1] and
-// buffer_[-2] == buffer_[(1 << window_bits) - 2].
-class RingBuffer {
- public:
- RingBuffer(int window_bits, int tail_bits)
- : size_(1u << window_bits),
- mask_((1u << window_bits) - 1),
- tail_size_(1u << tail_bits),
- pos_(0) {
- static const size_t kSlackForEightByteHashingEverywhere = 7;
- const size_t buflen = size_ + tail_size_;
- data_ = new uint8_t[2 + buflen + kSlackForEightByteHashingEverywhere];
- buffer_ = data_ + 2;
- for (size_t i = 0; i < kSlackForEightByteHashingEverywhere; ++i) {
- buffer_[buflen + i] = 0;
- }
- // Initialize the last two bytes and their copy to zero.
- buffer_[-2] = buffer_[size_ - 2] = 0;
- buffer_[-1] = buffer_[size_ - 1] = 0;
- }
- ~RingBuffer() {
- delete [] data_;
- }
-
- // Push bytes into the ring buffer.
- void Write(const uint8_t *bytes, size_t n) {
- const size_t masked_pos = pos_ & mask_;
- // The length of the writes is limited so that we do not need to worry
- // about a write
- WriteTail(bytes, n);
- if (PREDICT_TRUE(masked_pos + n <= size_)) {
- // A single write fits.
- memcpy(&buffer_[masked_pos], bytes, n);
- } else {
- // Split into two writes.
- // Copy into the end of the buffer, including the tail buffer.
- memcpy(&buffer_[masked_pos], bytes,
- std::min(n, (size_ + tail_size_) - masked_pos));
- // Copy into the beginning of the buffer
- memcpy(&buffer_[0], bytes + (size_ - masked_pos),
- n - (size_ - masked_pos));
- }
- buffer_[-2] = buffer_[size_ - 2];
- buffer_[-1] = buffer_[size_ - 1];
- pos_ += static_cast<uint32_t>(n);
- if (pos_ > (1u << 30)) { /* Wrap, but preserve not-a-first-lap feature. */
- pos_ = (pos_ & ((1u << 30) - 1)) | (1u << 30);
- }
- }
-
- void Reset() {
- pos_ = 0;
- }
-
- // Logical cursor position in the ring buffer.
- uint32_t position() const { return pos_; }
-
- // Bit mask for getting the physical position for a logical position.
- uint32_t mask() const { return mask_; }
-
- uint8_t *start() { return &buffer_[0]; }
- const uint8_t *start() const { return &buffer_[0]; }
-
- private:
- void WriteTail(const uint8_t *bytes, size_t n) {
- const size_t masked_pos = pos_ & mask_;
- if (PREDICT_FALSE(masked_pos < tail_size_)) {
- // Just fill the tail buffer with the beginning data.
- const size_t p = size_ + masked_pos;
- memcpy(&buffer_[p], bytes, std::min(n, tail_size_ - masked_pos));
- }
- }
-
- // Size of the ringbuffer is (1 << window_bits) + tail_size_.
- const uint32_t size_;
- const uint32_t mask_;
- const uint32_t tail_size_;
-
- // Position to write in the ring buffer.
- uint32_t pos_;
- // The actual ring buffer containing the copy of the last two bytes, the data,
- // and the copy of the beginning as a tail.
- uint8_t *data_;
- // The start of the ringbuffer.
- uint8_t *buffer_;
-};
-
-} // namespace brotli
-
-#endif // BROTLI_ENC_RINGBUFFER_H_