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
|
//===- BinaryStreamReader.cpp - Reads objects from a binary stream --------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "llvm/Support/BinaryStreamReader.h"
#include "llvm/Support/BinaryStreamError.h"
#include "llvm/Support/BinaryStreamRef.h"
#include "llvm/Support/LEB128.h"
using namespace llvm;
using endianness = llvm::support::endianness;
BinaryStreamReader::BinaryStreamReader(BinaryStreamRef Ref) : Stream(Ref) {}
BinaryStreamReader::BinaryStreamReader(BinaryStream &Stream) : Stream(Stream) {}
BinaryStreamReader::BinaryStreamReader(ArrayRef<uint8_t> Data,
endianness Endian)
: Stream(Data, Endian) {}
BinaryStreamReader::BinaryStreamReader(StringRef Data, endianness Endian)
: Stream(Data, Endian) {}
Error BinaryStreamReader::readLongestContiguousChunk(
ArrayRef<uint8_t> &Buffer) {
if (auto EC = Stream.readLongestContiguousChunk(Offset, Buffer))
return EC;
Offset += Buffer.size();
return Error::success();
}
Error BinaryStreamReader::readBytes(ArrayRef<uint8_t> &Buffer, uint32_t Size) {
if (auto EC = Stream.readBytes(Offset, Size, Buffer))
return EC;
Offset += Size;
return Error::success();
}
Error BinaryStreamReader::readULEB128(uint64_t &Dest) {
SmallVector<uint8_t, 10> EncodedBytes;
ArrayRef<uint8_t> NextByte;
// Copy the encoded ULEB into the buffer.
do {
if (auto Err = readBytes(NextByte, 1))
return Err;
EncodedBytes.push_back(NextByte[0]);
} while (NextByte[0] & 0x80);
Dest = decodeULEB128(EncodedBytes.begin(), nullptr, EncodedBytes.end());
return Error::success();
}
Error BinaryStreamReader::readSLEB128(int64_t &Dest) {
SmallVector<uint8_t, 10> EncodedBytes;
ArrayRef<uint8_t> NextByte;
// Copy the encoded ULEB into the buffer.
do {
if (auto Err = readBytes(NextByte, 1))
return Err;
EncodedBytes.push_back(NextByte[0]);
} while (NextByte[0] & 0x80);
Dest = decodeSLEB128(EncodedBytes.begin(), nullptr, EncodedBytes.end());
return Error::success();
}
Error BinaryStreamReader::readCString(StringRef &Dest) {
uint32_t OriginalOffset = getOffset();
uint32_t FoundOffset = 0;
while (true) {
uint32_t ThisOffset = getOffset();
ArrayRef<uint8_t> Buffer;
if (auto EC = readLongestContiguousChunk(Buffer))
return EC;
StringRef S(reinterpret_cast<const char *>(Buffer.begin()), Buffer.size());
size_t Pos = S.find_first_of('\0');
if (LLVM_LIKELY(Pos != StringRef::npos)) {
FoundOffset = Pos + ThisOffset;
break;
}
}
assert(FoundOffset >= OriginalOffset);
setOffset(OriginalOffset);
size_t Length = FoundOffset - OriginalOffset;
if (auto EC = readFixedString(Dest, Length))
return EC;
// Now set the offset back to after the null terminator.
setOffset(FoundOffset + 1);
return Error::success();
}
Error BinaryStreamReader::readWideString(ArrayRef<UTF16> &Dest) {
uint32_t Length = 0;
uint32_t OriginalOffset = getOffset();
const UTF16 *C;
while (true) {
if (auto EC = readObject(C))
return EC;
if (*C == 0x0000)
break;
++Length;
}
uint32_t NewOffset = getOffset();
setOffset(OriginalOffset);
if (auto EC = readArray(Dest, Length))
return EC;
setOffset(NewOffset);
return Error::success();
}
Error BinaryStreamReader::readFixedString(StringRef &Dest, uint32_t Length) {
ArrayRef<uint8_t> Bytes;
if (auto EC = readBytes(Bytes, Length))
return EC;
Dest = StringRef(reinterpret_cast<const char *>(Bytes.begin()), Bytes.size());
return Error::success();
}
Error BinaryStreamReader::readStreamRef(BinaryStreamRef &Ref) {
return readStreamRef(Ref, bytesRemaining());
}
Error BinaryStreamReader::readStreamRef(BinaryStreamRef &Ref, uint32_t Length) {
if (bytesRemaining() < Length)
return make_error<BinaryStreamError>(stream_error_code::stream_too_short);
Ref = Stream.slice(Offset, Length);
Offset += Length;
return Error::success();
}
Error BinaryStreamReader::readSubstream(BinarySubstreamRef &Ref,
uint32_t Length) {
Ref.Offset = getOffset();
return readStreamRef(Ref.StreamData, Length);
}
Error BinaryStreamReader::skip(uint32_t Amount) {
if (Amount > bytesRemaining())
return make_error<BinaryStreamError>(stream_error_code::stream_too_short);
Offset += Amount;
return Error::success();
}
Error BinaryStreamReader::padToAlignment(uint32_t Align) {
uint32_t NewOffset = alignTo(Offset, Align);
return skip(NewOffset - Offset);
}
uint8_t BinaryStreamReader::peek() const {
ArrayRef<uint8_t> Buffer;
auto EC = Stream.readBytes(Offset, 1, Buffer);
assert(!EC && "Cannot peek an empty buffer!");
llvm::consumeError(std::move(EC));
return Buffer[0];
}
std::pair<BinaryStreamReader, BinaryStreamReader>
BinaryStreamReader::split(uint32_t Off) const {
assert(getLength() >= Off);
BinaryStreamRef First = Stream.drop_front(Offset);
BinaryStreamRef Second = First.drop_front(Off);
First = First.keep_front(Off);
BinaryStreamReader W1{First};
BinaryStreamReader W2{Second};
return std::make_pair(W1, W2);
}
|
