blob: 191bf6be8386726dea38220693a74e2e483e6841 (
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
|
/* 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 nsHtml5String_h
#define nsHtml5String_h
#include "nsString.h"
class nsHtml5TreeBuilder;
/**
* A pass-by-value type that combines an unsafe `nsStringBuffer*` with its
* logical length (`uint32_t`). (`nsStringBuffer` knows its capacity but not
* its logical length, i.e. how much of the capacity is in use.)
*
* Holding or passing this type is as unsafe as holding or passing
* `nsStringBuffer*`.
*
* Empty strings and null strings are distinct. Since an empty nsString does
* not have a an `nsStringBuffer`, both empty and null `nsHtml5String` have
* `nullptr` as `mBuffer`. If `mBuffer` is `nullptr`, the empty case is marked
* with `mLength` being zero and the null case with `mLength` being non-zero.
*/
class nsHtml5String final
{
public:
/**
* Default constructor.
*/
inline nsHtml5String()
: nsHtml5String(nullptr)
{
}
/**
* Constructor from nullptr.
*/
inline MOZ_IMPLICIT nsHtml5String(decltype(nullptr))
: mBuffer(nullptr)
, mLength(UINT32_MAX)
{
}
inline uint32_t Length() const { return mBuffer ? mLength : 0; }
/**
* False iff the string is logically null
*/
inline MOZ_IMPLICIT operator bool() const { return !(!mBuffer && mLength); }
void ToString(nsAString& aString);
void CopyToBuffer(char16_t* aBuffer);
bool LowerCaseEqualsASCII(const char* aLowerCaseLiteral);
bool EqualsASCII(const char* aLiteral);
bool LowerCaseStartsWithASCII(const char* aLowerCaseLiteral);
bool Equals(nsHtml5String aOther);
nsHtml5String Clone();
void Release();
static nsHtml5String FromBuffer(char16_t* aBuffer,
int32_t aLength,
nsHtml5TreeBuilder* aTreeBuilder);
static nsHtml5String FromLiteral(const char* aLiteral);
static nsHtml5String FromString(const nsAString& aString);
static nsHtml5String EmptyString();
private:
/**
* Constructor from raw parts.
*/
nsHtml5String(already_AddRefed<nsStringBuffer> aBuffer, uint32_t aLength);
/**
* nullptr if the string is logically null or logically empty
*/
nsStringBuffer* mBuffer;
/**
* The length of the string. non-zero if the string is logically null.
*/
uint32_t mLength;
};
#endif // nsHtml5String_h
|
