Move shared files in net/quic/ into net/quic/core/

net/quic/quic_data_writer.cc

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "net/quic/quic_data_writer.h"
-
-#include <stdint.h>
-#include <algorithm>
-#include <limits>
-
-using base::StringPiece;
-using std::numeric_limits;
-
-namespace net {
-
-QuicDataWriter::QuicDataWriter(size_t size, char* buffer)
-    : buffer_(buffer), capacity_(size), length_(0) {}
-
-QuicDataWriter::~QuicDataWriter() {}
-
-char* QuicDataWriter::data() {
-  return buffer_;
-}
-
-bool QuicDataWriter::WriteUInt8(uint8_t value) {
-  return WriteBytes(&value, sizeof(value));
-}
-
-bool QuicDataWriter::WriteUInt16(uint16_t value) {
-  return WriteBytes(&value, sizeof(value));
-}
-
-bool QuicDataWriter::WriteUInt32(uint32_t value) {
-  return WriteBytes(&value, sizeof(value));
-}
-
-bool QuicDataWriter::WriteUInt48(uint64_t value) {
-  uint16_t hi = static_cast<uint16_t>(value >> 32);
-  uint32_t lo = static_cast<uint32_t>(value);
-  return WriteUInt32(lo) && WriteUInt16(hi);
-}
-
-bool QuicDataWriter::WriteUInt64(uint64_t value) {
-  return WriteBytes(&value, sizeof(value));
-}
-
-bool QuicDataWriter::WriteUFloat16(uint64_t value) {
-  uint16_t result;
-  if (value < (UINT64_C(1) << kUFloat16MantissaEffectiveBits)) {
-    // Fast path: either the value is denormalized, or has exponent zero.
-    // Both cases are represented by the value itself.
-    result = static_cast<uint16_t>(value);
-  } else if (value >= kUFloat16MaxValue) {
-    // Value is out of range; clamp it to the maximum representable.
-    result = numeric_limits<uint16_t>::max();
-  } else {
-    // The highest bit is between position 13 and 42 (zero-based), which
-    // corresponds to exponent 1-30. In the output, mantissa is from 0 to 10,
-    // hidden bit is 11 and exponent is 11 to 15. Shift the highest bit to 11
-    // and count the shifts.
-    uint16_t exponent = 0;
-    for (uint16_t offset = 16; offset > 0; offset /= 2) {
-      // Right-shift the value until the highest bit is in position 11.
-      // For offset of 16, 8, 4, 2 and 1 (binary search over 1-30),
-      // shift if the bit is at or above 11 + offset.
-      if (value >= (UINT64_C(1) << (kUFloat16MantissaBits + offset))) {
-        exponent += offset;
-        value >>= offset;
-      }
-    }
-
-    DCHECK_GE(exponent, 1);
-    DCHECK_LE(exponent, kUFloat16MaxExponent);
-    DCHECK_GE(value, UINT64_C(1) << kUFloat16MantissaBits);
-    DCHECK_LT(value, UINT64_C(1) << kUFloat16MantissaEffectiveBits);
-
-    // Hidden bit (position 11) is set. We should remove it and increment the
-    // exponent. Equivalently, we just add it to the exponent.
-    // This hides the bit.
-    result = static_cast<uint16_t>(value + (exponent << kUFloat16MantissaBits));
-  }
-
-  return WriteBytes(&result, sizeof(result));
-}
-
-bool QuicDataWriter::WriteStringPiece16(StringPiece val) {
-  if (val.size() > numeric_limits<uint16_t>::max()) {
-    return false;
-  }
-  if (!WriteUInt16(static_cast<uint16_t>(val.size()))) {
-    return false;
-  }
-  return WriteBytes(val.data(), val.size());
-}
-
-char* QuicDataWriter::BeginWrite(size_t length) {
-  if (length_ > capacity_) {
-    return nullptr;
-  }
-
-  if (capacity_ - length_ < length) {
-    return nullptr;
-  }
-
-#ifdef ARCH_CPU_64_BITS
-  DCHECK_LE(length, std::numeric_limits<uint32_t>::max());
-#endif
-
-  return buffer_ + length_;
-}
-
-bool QuicDataWriter::WriteBytes(const void* data, size_t data_len) {
-  char* dest = BeginWrite(data_len);
-  if (!dest) {
-    return false;
-  }
-
-  memcpy(dest, data, data_len);
-
-  length_ += data_len;
-  return true;
-}
-
-bool QuicDataWriter::WriteRepeatedByte(uint8_t byte, size_t count) {
-  char* dest = BeginWrite(count);
-  if (!dest) {
-    return false;
-  }
-
-  memset(dest, byte, count);
-
-  length_ += count;
-  return true;
-}
-
-void QuicDataWriter::WritePadding() {
-  DCHECK_LE(length_, capacity_);
-  if (length_ > capacity_) {
-    return;
-  }
-  memset(buffer_ + length_, 0x00, capacity_ - length_);
-  length_ = capacity_;
-}
-
-}  // namespace net