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Issue 761903003: Update from https://crrev.com/306655 (Closed) Base URL: git@github.com:domokit/mojo.git@master
Patch Set: Created 6 years ago
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1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. 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 2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file. 3 // found in the LICENSE file.
4 4
5 #include "net/quic/quic_data_writer.h" 5 #include "net/quic/quic_data_writer.h"
6 6
7 #include <algorithm> 7 #include <algorithm>
8 #include <limits> 8 #include <limits>
9 #include <string> 9 #include <string>
10 10
11 #include "base/basictypes.h" 11 #include "base/basictypes.h"
12 #include "base/logging.h" 12 #include "base/logging.h"
13 13
14 using base::StringPiece;
15 using std::numeric_limits;
16
17 namespace net { 14 namespace net {
18 15
19 QuicDataWriter::QuicDataWriter(size_t size) 16 QuicDataWriter::QuicDataWriter(size_t size)
20 : buffer_(new char[size]), 17 : buffer_(new char[size]),
21 capacity_(size), 18 capacity_(size),
22 length_(0) { 19 length_(0) {
23 } 20 }
24 21
25 QuicDataWriter::~QuicDataWriter() { 22 QuicDataWriter::~QuicDataWriter() {
26 delete[] buffer_; 23 delete[] buffer_;
(...skipping 13 matching lines...) Expand all
40 37
41 bool QuicDataWriter::WriteUInt16(uint16 value) { 38 bool QuicDataWriter::WriteUInt16(uint16 value) {
42 return WriteBytes(&value, sizeof(value)); 39 return WriteBytes(&value, sizeof(value));
43 } 40 }
44 41
45 bool QuicDataWriter::WriteUInt32(uint32 value) { 42 bool QuicDataWriter::WriteUInt32(uint32 value) {
46 return WriteBytes(&value, sizeof(value)); 43 return WriteBytes(&value, sizeof(value));
47 } 44 }
48 45
49 bool QuicDataWriter::WriteUInt48(uint64 value) { 46 bool QuicDataWriter::WriteUInt48(uint64 value) {
50 uint32 hi = value >> 32; 47 uint16 hi = static_cast<uint16>(value >> 32);
51 uint32 lo = value & GG_UINT64_C(0x00000000FFFFFFFF); 48 uint32 lo = static_cast<uint32>(value);
52 return WriteUInt32(lo) && WriteUInt16(hi); 49 return WriteUInt32(lo) && WriteUInt16(hi);
53 } 50 }
54 51
55 bool QuicDataWriter::WriteUInt64(uint64 value) { 52 bool QuicDataWriter::WriteUInt64(uint64 value) {
56 return WriteBytes(&value, sizeof(value)); 53 return WriteBytes(&value, sizeof(value));
57 } 54 }
58 55
59 bool QuicDataWriter::WriteUFloat16(uint64 value) { 56 bool QuicDataWriter::WriteUFloat16(uint64 value) {
60 uint16 result; 57 uint16 result;
61 if (value < (GG_UINT64_C(1) << kUFloat16MantissaEffectiveBits)) { 58 if (value < (GG_UINT64_C(1) << kUFloat16MantissaEffectiveBits)) {
62 // Fast path: either the value is denormalized, or has exponent zero. 59 // Fast path: either the value is denormalized, or has exponent zero.
63 // Both cases are represented by the value itself. 60 // Both cases are represented by the value itself.
64 result = value; 61 result = static_cast<uint16>(value);
65 } else if (value >= kUFloat16MaxValue) { 62 } else if (value >= kUFloat16MaxValue) {
66 // Value is out of range; clamp it to the maximum representable. 63 // Value is out of range; clamp it to the maximum representable.
67 result = numeric_limits<uint16>::max(); 64 result = std::numeric_limits<uint16>::max();
68 } else { 65 } else {
69 // The highest bit is between position 13 and 42 (zero-based), which 66 // The highest bit is between position 13 and 42 (zero-based), which
70 // corresponds to exponent 1-30. In the output, mantissa is from 0 to 10, 67 // corresponds to exponent 1-30. In the output, mantissa is from 0 to 10,
71 // hidden bit is 11 and exponent is 11 to 15. Shift the highest bit to 11 68 // hidden bit is 11 and exponent is 11 to 15. Shift the highest bit to 11
72 // and count the shifts. 69 // and count the shifts.
73 uint16 exponent = 0; 70 uint16 exponent = 0;
74 for (uint16 offset = 16; offset > 0; offset /= 2) { 71 for (uint16 offset = 16; offset > 0; offset /= 2) {
75 // Right-shift the value until the highest bit is in position 11. 72 // Right-shift the value until the highest bit is in position 11.
76 // For offset of 16, 8, 4, 2 and 1 (binary search over 1-30), 73 // For offset of 16, 8, 4, 2 and 1 (binary search over 1-30),
77 // shift if the bit is at or above 11 + offset. 74 // shift if the bit is at or above 11 + offset.
78 if (value >= (GG_UINT64_C(1) << (kUFloat16MantissaBits + offset))) { 75 if (value >= (GG_UINT64_C(1) << (kUFloat16MantissaBits + offset))) {
79 exponent += offset; 76 exponent += offset;
80 value >>= offset; 77 value >>= offset;
81 } 78 }
82 } 79 }
83 80
84 DCHECK_GE(exponent, 1); 81 DCHECK_GE(exponent, 1);
85 DCHECK_LE(exponent, kUFloat16MaxExponent); 82 DCHECK_LE(exponent, kUFloat16MaxExponent);
86 DCHECK_GE(value, GG_UINT64_C(1) << kUFloat16MantissaBits); 83 DCHECK_GE(value, GG_UINT64_C(1) << kUFloat16MantissaBits);
87 DCHECK_LT(value, GG_UINT64_C(1) << kUFloat16MantissaEffectiveBits); 84 DCHECK_LT(value, GG_UINT64_C(1) << kUFloat16MantissaEffectiveBits);
88 85
89 // Hidden bit (position 11) is set. We should remove it and increment the 86 // Hidden bit (position 11) is set. We should remove it and increment the
90 // exponent. Equivalently, we just add it to the exponent. 87 // exponent. Equivalently, we just add it to the exponent.
91 // This hides the bit. 88 // This hides the bit.
92 result = value + (exponent << kUFloat16MantissaBits); 89 result = static_cast<uint16>(value + (exponent << kUFloat16MantissaBits));
93 } 90 }
94 91
95 return WriteBytes(&result, sizeof(result)); 92 return WriteBytes(&result, sizeof(result));
96 } 93 }
97 94
98 bool QuicDataWriter::WriteStringPiece16(StringPiece val) { 95 bool QuicDataWriter::WriteStringPiece16(base::StringPiece val) {
99 if (val.length() > numeric_limits<uint16>::max()) { 96 if (val.size() > std::numeric_limits<uint16>::max()) {
100 return false; 97 return false;
101 } 98 }
102 if (!WriteUInt16(val.size())) { 99 if (!WriteUInt16(static_cast<uint16>(val.size()))) {
103 return false; 100 return false;
104 } 101 }
105 return WriteBytes(val.data(), val.size()); 102 return WriteBytes(val.data(), val.size());
106 } 103 }
107 104
108 bool QuicDataWriter::WriteIOVector(const IOVector& data) { 105 bool QuicDataWriter::WriteIOVector(const IOVector& data) {
109 char *dest = BeginWrite(data.TotalBufferSize()); 106 char *dest = BeginWrite(data.TotalBufferSize());
110 if (!dest) { 107 if (!dest) {
111 return false; 108 return false;
112 } 109 }
113 for (size_t i = 0; i < data.Size(); ++i) { 110 for (size_t i = 0; i < data.Size(); ++i) {
114 WriteBytes(data.iovec()[i].iov_base, data.iovec()[i].iov_len); 111 WriteBytes(data.iovec()[i].iov_base, data.iovec()[i].iov_len);
115 } 112 }
116 113
117 return true; 114 return true;
118 } 115 }
119 116
120 char* QuicDataWriter::BeginWrite(size_t length) { 117 char* QuicDataWriter::BeginWrite(size_t length) {
121 if (length_ > capacity_) { 118 if (length_ > capacity_) {
122 return nullptr; 119 return nullptr;
123 } 120 }
124 121
125 if (capacity_ - length_ < length) { 122 if (capacity_ - length_ < length) {
126 return nullptr; 123 return nullptr;
127 } 124 }
128 125
129 #ifdef ARCH_CPU_64_BITS 126 #ifdef ARCH_CPU_64_BITS
130 DCHECK_LE(length, numeric_limits<uint32>::max()); 127 DCHECK_LE(length, std::numeric_limits<uint32>::max());
131 #endif 128 #endif
132 129
133 return buffer_ + length_; 130 return buffer_ + length_;
134 } 131 }
135 132
136 bool QuicDataWriter::WriteBytes(const void* data, size_t data_len) { 133 bool QuicDataWriter::WriteBytes(const void* data, size_t data_len) {
137 char* dest = BeginWrite(data_len); 134 char* dest = BeginWrite(data_len);
138 if (!dest) { 135 if (!dest) {
139 return false; 136 return false;
140 } 137 }
(...skipping 52 matching lines...) Expand 10 before | Expand all | Expand 10 after
193 DCHECK_LT(offset, capacity_); 190 DCHECK_LT(offset, capacity_);
194 size_t latched_length = length_; 191 size_t latched_length = length_;
195 length_ = offset; 192 length_ = offset;
196 bool success = WriteUInt48(value); 193 bool success = WriteUInt48(value);
197 DCHECK_LE(length_, latched_length); 194 DCHECK_LE(length_, latched_length);
198 length_ = latched_length; 195 length_ = latched_length;
199 return success; 196 return success;
200 } 197 }
201 198
202 } // namespace net 199 } // namespace net
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