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
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
|
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: set ts=8 sts=2 et sw=2 tw=80:
* 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/. */
#include "util/StringBuffer.h"
#include "mozilla/Latin1.h"
#include "mozilla/Range.h"
#include <algorithm>
#include "frontend/ParserAtom.h" // frontend::{ParserAtomsTable, TaggedParserAtomIndex
#include "js/friend/ErrorMessages.h" // js::GetErrorMessage, JSMSG_*
#include "vm/BigIntType.h"
#include "vm/StaticStrings.h"
#include "vm/JSObject-inl.h"
#include "vm/StringType-inl.h"
using namespace js;
template <typename CharT, class Buffer>
static CharT* ExtractWellSized(Buffer& cb) {
size_t capacity = cb.capacity();
size_t length = cb.length();
StringBufferAllocPolicy allocPolicy = cb.allocPolicy();
CharT* buf = cb.extractOrCopyRawBuffer();
if (!buf) {
return nullptr;
}
// For medium/big buffers, avoid wasting more than 1/4 of the memory. Very
// small strings will not reach here because they will have been stored in a
// JSInlineString. Don't bother shrinking the allocation unless at least 80
// bytes will be saved, which is a somewhat arbitrary number (though it does
// correspond to a mozjemalloc size class.)
MOZ_ASSERT(capacity >= length);
constexpr size_t minCharsToReclaim = 80 / sizeof(CharT);
if (capacity - length >= minCharsToReclaim &&
capacity - length > capacity / 4) {
CharT* tmp = allocPolicy.pod_realloc<CharT>(buf, capacity, length);
if (!tmp) {
allocPolicy.free_(buf);
return nullptr;
}
buf = tmp;
}
return buf;
}
char16_t* StringBuffer::stealChars() {
if (isLatin1() && !inflateChars()) {
return nullptr;
}
return ExtractWellSized<char16_t>(twoByteChars());
}
bool StringBuffer::inflateChars() {
MOZ_ASSERT(isLatin1());
TwoByteCharBuffer twoByte(latin1Chars().allocPolicy());
/*
* Note: we don't use Vector::capacity() because it always returns a
* value >= sInlineCapacity. Since Latin1CharBuffer::sInlineCapacity >
* TwoByteCharBuffer::sInlineCapacitychars, we'd always malloc here.
*/
size_t capacity = std::max(reserved_, latin1Chars().length());
if (!twoByte.reserve(capacity)) {
return false;
}
twoByte.infallibleGrowByUninitialized(latin1Chars().length());
mozilla::ConvertLatin1toUtf16(mozilla::AsChars(latin1Chars()), twoByte);
cb.destroy();
cb.construct<TwoByteCharBuffer>(std::move(twoByte));
return true;
}
bool StringBuffer::append(const frontend::ParserAtomsTable& parserAtoms,
frontend::TaggedParserAtomIndex atom) {
return parserAtoms.appendTo(*this, atom);
}
template <typename CharT>
JSLinearString* StringBuffer::finishStringInternal(JSContext* cx) {
size_t len = length();
if (JSAtom* staticStr = cx->staticStrings().lookup(begin<CharT>(), len)) {
return staticStr;
}
if (JSInlineString::lengthFits<CharT>(len)) {
mozilla::Range<const CharT> range(begin<CharT>(), len);
return NewInlineString<CanGC>(cx, range);
}
UniquePtr<CharT[], JS::FreePolicy> buf(
ExtractWellSized<CharT>(chars<CharT>()));
if (!buf) {
return nullptr;
}
JSLinearString* str = NewStringDontDeflate<CanGC>(cx, std::move(buf), len);
if (!str) {
return nullptr;
}
return str;
}
JSLinearString* JSStringBuilder::finishString() {
MOZ_ASSERT(maybeCx_);
size_t len = length();
if (len == 0) {
return maybeCx_->names().empty;
}
if (MOZ_UNLIKELY(!JSString::validateLength(maybeCx_, len))) {
return nullptr;
}
static_assert(JSFatInlineString::MAX_LENGTH_TWO_BYTE <
TwoByteCharBuffer::InlineLength);
static_assert(JSFatInlineString::MAX_LENGTH_LATIN1 <
Latin1CharBuffer::InlineLength);
return isLatin1() ? finishStringInternal<Latin1Char>(maybeCx_)
: finishStringInternal<char16_t>(maybeCx_);
}
JSAtom* StringBuffer::finishAtom() {
MOZ_ASSERT(maybeCx_);
size_t len = length();
if (len == 0) {
return maybeCx_->names().empty;
}
if (isLatin1()) {
JSAtom* atom = AtomizeChars(maybeCx_, latin1Chars().begin(), len);
latin1Chars().clear();
return atom;
}
JSAtom* atom = AtomizeChars(maybeCx_, twoByteChars().begin(), len);
twoByteChars().clear();
return atom;
}
frontend::TaggedParserAtomIndex StringBuffer::finishParserAtom(
frontend::ParserAtomsTable& parserAtoms, FrontendContext* fc) {
size_t len = length();
if (len == 0) {
return frontend::TaggedParserAtomIndex::WellKnown::empty();
}
if (isLatin1()) {
auto result = parserAtoms.internLatin1(fc, latin1Chars().begin(), len);
latin1Chars().clear();
return result;
}
auto result = parserAtoms.internChar16(fc, twoByteChars().begin(), len);
twoByteChars().clear();
return result;
}
bool js::ValueToStringBufferSlow(JSContext* cx, const Value& arg,
StringBuffer& sb) {
RootedValue v(cx, arg);
if (!ToPrimitive(cx, JSTYPE_STRING, &v)) {
return false;
}
if (v.isString()) {
return sb.append(v.toString());
}
if (v.isNumber()) {
return NumberValueToStringBuffer(v, sb);
}
if (v.isBoolean()) {
return BooleanToStringBuffer(v.toBoolean(), sb);
}
if (v.isNull()) {
return sb.append(cx->names().null);
}
if (v.isSymbol()) {
JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
JSMSG_SYMBOL_TO_STRING);
return false;
}
if (v.isBigInt()) {
RootedBigInt i(cx, v.toBigInt());
JSLinearString* str = BigInt::toString<CanGC>(cx, i, 10);
if (!str) {
return false;
}
return sb.append(str);
}
MOZ_ASSERT(v.isUndefined());
return sb.append(cx->names().undefined);
}
|
