blob: aa8b278ec0117fdf4308f4a4a8e39876739043a1 [file] [log] [blame]
// 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 "quiche/quic/core/quic_data_reader.h"
#include "absl/strings/string_view.h"
#include "quiche/quic/core/quic_packets.h"
#include "quiche/quic/core/quic_utils.h"
#include "quiche/quic/platform/api/quic_bug_tracker.h"
#include "quiche/quic/platform/api/quic_flags.h"
#include "quiche/common/quiche_endian.h"
namespace quic {
QuicDataReader::QuicDataReader(absl::string_view data)
: quiche::QuicheDataReader(data) {}
QuicDataReader::QuicDataReader(const char* data, const size_t len)
: QuicDataReader(data, len, quiche::NETWORK_BYTE_ORDER) {}
QuicDataReader::QuicDataReader(const char* data, const size_t len,
quiche::Endianness endianness)
: quiche::QuicheDataReader(data, len, endianness) {}
bool QuicDataReader::ReadUFloat16(uint64_t* result) {
uint16_t value;
if (!ReadUInt16(&value)) {
return false;
*result = value;
if (*result < (1 << kUFloat16MantissaEffectiveBits)) {
// Fast path: either the value is denormalized (no hidden bit), or
// normalized (hidden bit set, exponent offset by one) with exponent zero.
// Zero exponent offset by one sets the bit exactly where the hidden bit is.
// So in both cases the value encodes itself.
return true;
uint16_t exponent =
value >> kUFloat16MantissaBits; // No sign extend on uint!
// After the fast pass, the exponent is at least one (offset by one).
// Un-offset the exponent.
QUICHE_DCHECK_GE(exponent, 1);
QUICHE_DCHECK_LE(exponent, kUFloat16MaxExponent);
// Here we need to clear the exponent and set the hidden bit. We have already
// decremented the exponent, so when we subtract it, it leaves behind the
// hidden bit.
*result -= exponent << kUFloat16MantissaBits;
*result <<= exponent;
static_cast<uint64_t>(1 << kUFloat16MantissaEffectiveBits));
QUICHE_DCHECK_LE(*result, kUFloat16MaxValue);
return true;
bool QuicDataReader::ReadConnectionId(QuicConnectionId* connection_id,
uint8_t length) {
if (length == 0) {
return true;
if (BytesRemaining() < length) {
return false;
const bool ok =
ReadBytes(connection_id->mutable_data(), connection_id->length());
return ok;
bool QuicDataReader::ReadLengthPrefixedConnectionId(
QuicConnectionId* connection_id) {
uint8_t connection_id_length;
if (!ReadUInt8(&connection_id_length)) {
return false;
return ReadConnectionId(connection_id, connection_id_length);
#undef ENDPOINT // undef for jumbo builds
} // namespace quic