blob: e26b0c3bca8289dc3f3fac7d96960c96c2f159c2 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
|
/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2; -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef IOBuffers_h
#define IOBuffers_h
#include "mozilla/Assertions.h"
#include "mozilla/CheckedInt.h"
#include "mozilla/EndianUtils.h"
#include "mozilla/EnumSet.h"
#include "mozilla/Range.h"
#include "mozilla/Span.h"
#include "nsString.h"
#include "nsTArray.h"
namespace mozilla {
namespace loader {
class OutputBuffer {
public:
OutputBuffer() {}
uint8_t* write(size_t size) {
auto buf = data.AppendElements(size);
cursor_ += size;
return buf;
}
void codeUint8(const uint8_t& val) { *write(sizeof val) = val; }
template <typename T>
void codeUint8(const EnumSet<T>& val) {
// EnumSets are always represented as uint32_t values, so we need to
// assert that the value actually fits in a uint8 before writing it.
uint32_t value = val.serialize();
codeUint8(CheckedUint8(value).value());
}
void codeUint16(const uint16_t& val) {
LittleEndian::writeUint16(write(sizeof val), val);
}
void codeUint32(const uint32_t& val) {
LittleEndian::writeUint32(write(sizeof val), val);
}
void codeString(const nsCString& str) {
auto len = CheckedUint16(str.Length()).value();
codeUint16(len);
memcpy(write(len), str.BeginReading(), len);
}
size_t cursor() const { return cursor_; }
uint8_t* Get() { return data.Elements(); }
const uint8_t* Get() const { return data.Elements(); }
private:
nsTArray<uint8_t> data;
size_t cursor_ = 0;
};
class InputBuffer {
public:
explicit InputBuffer(const Range<uint8_t>& buffer) : data(buffer) {}
const uint8_t* read(size_t size) {
MOZ_ASSERT(checkCapacity(size));
auto buf = &data[cursor_];
cursor_ += size;
return buf;
}
bool codeUint8(uint8_t& val) {
if (checkCapacity(sizeof val)) {
val = *read(sizeof val);
}
return !error_;
}
template <typename T>
bool codeUint8(EnumSet<T>& val) {
uint8_t value;
if (codeUint8(value)) {
val.deserialize(value);
}
return !error_;
}
bool codeUint16(uint16_t& val) {
if (checkCapacity(sizeof val)) {
val = LittleEndian::readUint16(read(sizeof val));
}
return !error_;
}
bool codeUint32(uint32_t& val) {
if (checkCapacity(sizeof val)) {
val = LittleEndian::readUint32(read(sizeof val));
}
return !error_;
}
bool codeString(nsCString& str) {
uint16_t len;
if (codeUint16(len)) {
if (checkCapacity(len)) {
str.SetLength(len);
memcpy(str.BeginWriting(), read(len), len);
}
}
return !error_;
}
bool error() { return error_; }
bool finished() { return error_ || !remainingCapacity(); }
size_t remainingCapacity() { return data.length() - cursor_; }
size_t cursor() const { return cursor_; }
const uint8_t* Get() const { return data.begin().get(); }
private:
bool checkCapacity(size_t size) {
if (size > remainingCapacity()) {
error_ = true;
}
return !error_;
}
bool error_ = false;
public:
const Range<uint8_t>& data;
size_t cursor_ = 0;
};
} // namespace loader
} // namespace mozilla
#endif // IOBuffers_h
|
