1// Copyright (c) 2012 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#include "net/quic/quic_bandwidth.h"
6
7#include "base/logging.h"
8#include "base/time/time.h"
9
10namespace net {
11
12// Highest number that QuicBandwidth can hold.
13const int64 kQuicInfiniteBandwidth = GG_INT64_C(0x7fffffffffffffff);
14
15// static
16QuicBandwidth QuicBandwidth::Zero() {
17  return QuicBandwidth(0);
18}
19
20// static
21QuicBandwidth QuicBandwidth::FromBitsPerSecond(int64 bits_per_second) {
22  return QuicBandwidth(bits_per_second);
23}
24
25// static
26QuicBandwidth QuicBandwidth::FromKBitsPerSecond(int64 k_bits_per_second) {
27  DCHECK(k_bits_per_second < kQuicInfiniteBandwidth / 1000);
28  return QuicBandwidth(k_bits_per_second * 1000);
29}
30
31// static
32QuicBandwidth QuicBandwidth::FromBytesPerSecond(int64 bytes_per_second) {
33  DCHECK(bytes_per_second < kQuicInfiniteBandwidth / 8);
34  return QuicBandwidth(bytes_per_second * 8);
35}
36
37// static
38QuicBandwidth QuicBandwidth::FromKBytesPerSecond(int64 k_bytes_per_second) {
39  DCHECK(k_bytes_per_second < kQuicInfiniteBandwidth / 8000);
40  return QuicBandwidth(k_bytes_per_second * 8000);
41}
42
43// static
44QuicBandwidth QuicBandwidth::FromBytesAndTimeDelta(QuicByteCount bytes,
45                                                   QuicTime::Delta delta) {
46  DCHECK_LT(bytes,
47            static_cast<uint64>(kQuicInfiniteBandwidth /
48                                (8 * base::Time::kMicrosecondsPerSecond)));
49  int64 bytes_per_second = (bytes * base::Time::kMicrosecondsPerSecond) /
50      delta.ToMicroseconds();
51  return QuicBandwidth(bytes_per_second * 8);
52}
53
54QuicBandwidth::QuicBandwidth(int64 bits_per_second)
55    : bits_per_second_(bits_per_second) {
56  DCHECK_GE(bits_per_second, 0);
57}
58
59int64 QuicBandwidth::ToBitsPerSecond() const {
60  return bits_per_second_;
61}
62
63int64 QuicBandwidth::ToKBitsPerSecond() const {
64  return bits_per_second_ / 1000;
65}
66
67int64 QuicBandwidth::ToBytesPerSecond() const {
68  return bits_per_second_ / 8;
69}
70
71int64 QuicBandwidth::ToKBytesPerSecond() const {
72  return bits_per_second_ / 8000;
73}
74
75QuicByteCount QuicBandwidth::ToBytesPerPeriod(
76    QuicTime::Delta time_period) const {
77  return ToBytesPerSecond() * time_period.ToMicroseconds() /
78      base::Time::kMicrosecondsPerSecond;
79}
80
81int64 QuicBandwidth::ToKBytesPerPeriod(QuicTime::Delta time_period) const {
82  return ToKBytesPerSecond() * time_period.ToMicroseconds() /
83      base::Time::kMicrosecondsPerSecond;
84}
85
86bool QuicBandwidth::IsZero() const {
87  return (bits_per_second_ == 0);
88}
89
90QuicBandwidth QuicBandwidth::Add(const QuicBandwidth& delta) const {
91  return QuicBandwidth(bits_per_second_ + delta.bits_per_second_);
92}
93
94QuicBandwidth QuicBandwidth::Subtract(const QuicBandwidth& delta) const {
95  return QuicBandwidth(bits_per_second_ - delta.bits_per_second_);
96}
97
98QuicBandwidth QuicBandwidth::Scale(float scale_factor) const {
99  return QuicBandwidth(bits_per_second_ * scale_factor);
100}
101
102QuicTime::Delta QuicBandwidth::TransferTime(QuicByteCount bytes) const {
103  return QuicTime::Delta::FromMicroseconds(
104      bytes * 8 * base::Time::kMicrosecondsPerSecond / bits_per_second_);
105}
106
107}  // namespace net
108