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
|
/*
* Copyright (C) 2015 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*/
#pragma once
#if ENABLE(CONTENT_EXTENSIONS)
namespace WebCore {
namespace ContentExtensions {
typedef uint8_t DFABytecode;
// Increment ContentExtensionStore::CurrentContentExtensionFileVersion
// when making any non-backwards-compatible changes to the bytecode.
// FIXME: Changes here should not require changes in WebKit2. Move all versioning to WebCore.
enum class DFABytecodeInstruction : uint8_t {
// CheckValue has two arguments:
// The value to check (1 byte),
// The distance to jump if the values are equal (1-4 bytes, signed).
CheckValueCaseInsensitive = 0x0,
CheckValueCaseSensitive = 0x1,
// Jump table if the input value is within a certain range.
// The lower value (1 byte).
// The higher value (1 byte).
// The distance to jump if the value is in the range
// for every character in the range (1-4 bytes, signed).
JumpTableCaseInsensitive = 0x2,
JumpTableCaseSensitive = 0x3,
// Jump to an offset if the input value is within a certain range.
// The lower value (1 byte).
// The higher value (1 byte).
// The distance to jump if the value is in the range (1-4 bytes, signed).
CheckValueRangeCaseInsensitive = 0x4,
CheckValueRangeCaseSensitive = 0x5,
// AppendAction has one argument:
// The action to append (4 bytes).
AppendAction = 0x6,
AppendActionWithIfCondition = 0x7,
// TestFlagsAndAppendAction has two arguments:
// The flags to check before appending (2 bytes).
// The action to append (4 bytes).
TestFlagsAndAppendAction = 0x8,
TestFlagsAndAppendActionWithIfCondition = 0x9,
// Terminate has no arguments.
Terminate = 0xA,
// Jump has one argument:
// The distance to jump (1-4 bytes, signed).
Jump = 0xB,
};
// The last four bits contain the instruction type.
const uint8_t DFABytecodeInstructionMask = 0x0F;
const uint8_t DFABytecodeJumpSizeMask = 0xF0;
// DFA bytecode starts with a 4 byte header which contains the size of this DFA.
typedef uint32_t DFAHeader;
// A DFABytecodeJumpSize is stored in the top four bits of the DFABytecodeInstructions that have a jump.
enum DFABytecodeJumpSize {
Int8 = 0x10,
Int16 = 0x20,
Int24 = 0x30,
Int32 = 0x40,
};
const int32_t Int24Max = (1 << 23) - 1;
const int32_t Int24Min = -(1 << 23);
static inline DFABytecodeJumpSize smallestPossibleJumpSize(int32_t longestPossibleJump)
{
if (longestPossibleJump <= std::numeric_limits<int8_t>::max() && longestPossibleJump >= std::numeric_limits<int8_t>::min())
return Int8;
if (longestPossibleJump <= std::numeric_limits<int16_t>::max() && longestPossibleJump >= std::numeric_limits<int16_t>::min())
return Int16;
if (longestPossibleJump <= Int24Max && longestPossibleJump >= Int24Min)
return Int24;
return Int32;
}
static inline size_t instructionSizeWithArguments(DFABytecodeInstruction instruction)
{
switch (instruction) {
case DFABytecodeInstruction::CheckValueCaseSensitive:
case DFABytecodeInstruction::CheckValueCaseInsensitive:
case DFABytecodeInstruction::JumpTableCaseInsensitive:
case DFABytecodeInstruction::JumpTableCaseSensitive:
case DFABytecodeInstruction::CheckValueRangeCaseSensitive:
case DFABytecodeInstruction::CheckValueRangeCaseInsensitive:
case DFABytecodeInstruction::Jump:
RELEASE_ASSERT_NOT_REACHED(); // Variable instruction size.
case DFABytecodeInstruction::AppendAction:
case DFABytecodeInstruction::AppendActionWithIfCondition:
return sizeof(DFABytecodeInstruction) + sizeof(uint32_t);
case DFABytecodeInstruction::TestFlagsAndAppendAction:
case DFABytecodeInstruction::TestFlagsAndAppendActionWithIfCondition:
return sizeof(DFABytecodeInstruction) + sizeof(uint16_t) + sizeof(uint32_t);
case DFABytecodeInstruction::Terminate:
return sizeof(DFABytecodeInstruction);
}
}
} // namespace ContentExtensions
} // namespace WebCore
#endif // ENABLE(CONTENT_EXTENSIONS)
|
