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
|
//==- MappedBlockStream.h - Discontiguous stream data in an MSF --*- C++ -*-==//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_DEBUGINFO_MSF_MAPPEDBLOCKSTREAM_H
#define LLVM_DEBUGINFO_MSF_MAPPEDBLOCKSTREAM_H
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/DebugInfo/MSF/MSFCommon.h"
#include "llvm/Support/Allocator.h"
#include "llvm/Support/BinaryStream.h"
#include "llvm/Support/BinaryStreamRef.h"
#include "llvm/Support/Endian.h"
#include "llvm/Support/Error.h"
#include <cstdint>
#include <memory>
#include <vector>
namespace llvm {
namespace msf {
struct MSFLayout;
/// MappedBlockStream represents data stored in an MSF file into chunks of a
/// particular size (called the Block Size), and whose chunks may not be
/// necessarily contiguous. The arrangement of these chunks MSF the file
/// is described by some other metadata contained within the MSF file. In
/// the case of a standard MSF Stream, the layout of the stream's blocks
/// is described by the MSF "directory", but in the case of the directory
/// itself, the layout is described by an array at a fixed location within
/// the MSF. MappedBlockStream provides methods for reading from and writing
/// to one of these streams transparently, as if it were a contiguous sequence
/// of bytes.
class MappedBlockStream : public BinaryStream {
friend class WritableMappedBlockStream;
public:
static std::unique_ptr<MappedBlockStream>
createStream(uint32_t BlockSize, const MSFStreamLayout &Layout,
BinaryStreamRef MsfData, BumpPtrAllocator &Allocator);
static std::unique_ptr<MappedBlockStream>
createIndexedStream(const MSFLayout &Layout, BinaryStreamRef MsfData,
uint32_t StreamIndex, BumpPtrAllocator &Allocator);
static std::unique_ptr<MappedBlockStream>
createFpmStream(const MSFLayout &Layout, BinaryStreamRef MsfData,
BumpPtrAllocator &Allocator);
static std::unique_ptr<MappedBlockStream>
createDirectoryStream(const MSFLayout &Layout, BinaryStreamRef MsfData,
BumpPtrAllocator &Allocator);
support::endianness getEndian() const override {
return support::little;
}
Error readBytes(uint32_t Offset, uint32_t Size,
ArrayRef<uint8_t> &Buffer) override;
Error readLongestContiguousChunk(uint32_t Offset,
ArrayRef<uint8_t> &Buffer) override;
uint32_t getLength() override;
BumpPtrAllocator &getAllocator() { return Allocator; }
void invalidateCache();
uint32_t getBlockSize() const { return BlockSize; }
uint32_t getNumBlocks() const { return StreamLayout.Blocks.size(); }
uint32_t getStreamLength() const { return StreamLayout.Length; }
protected:
MappedBlockStream(uint32_t BlockSize, const MSFStreamLayout &StreamLayout,
BinaryStreamRef MsfData, BumpPtrAllocator &Allocator);
private:
const MSFStreamLayout &getStreamLayout() const { return StreamLayout; }
void fixCacheAfterWrite(uint32_t Offset, ArrayRef<uint8_t> Data) const;
Error readBytes(uint32_t Offset, MutableArrayRef<uint8_t> Buffer);
bool tryReadContiguously(uint32_t Offset, uint32_t Size,
ArrayRef<uint8_t> &Buffer);
const uint32_t BlockSize;
const MSFStreamLayout StreamLayout;
BinaryStreamRef MsfData;
using CacheEntry = MutableArrayRef<uint8_t>;
// We just store the allocator by reference. We use this to allocate
// contiguous memory for things like arrays or strings that cross a block
// boundary, and this memory is expected to outlive the stream. For example,
// someone could create a stream, read some stuff, then close the stream, and
// we would like outstanding references to fields to remain valid since the
// entire file is mapped anyway. Because of that, the user must supply the
// allocator to allocate broken records from.
BumpPtrAllocator &Allocator;
DenseMap<uint32_t, std::vector<CacheEntry>> CacheMap;
};
class WritableMappedBlockStream : public WritableBinaryStream {
public:
static std::unique_ptr<WritableMappedBlockStream>
createStream(uint32_t BlockSize, const MSFStreamLayout &Layout,
WritableBinaryStreamRef MsfData, BumpPtrAllocator &Allocator);
static std::unique_ptr<WritableMappedBlockStream>
createIndexedStream(const MSFLayout &Layout, WritableBinaryStreamRef MsfData,
uint32_t StreamIndex, BumpPtrAllocator &Allocator);
static std::unique_ptr<WritableMappedBlockStream>
createDirectoryStream(const MSFLayout &Layout,
WritableBinaryStreamRef MsfData,
BumpPtrAllocator &Allocator);
static std::unique_ptr<WritableMappedBlockStream>
createFpmStream(const MSFLayout &Layout, WritableBinaryStreamRef MsfData,
BumpPtrAllocator &Allocator, bool AltFpm = false);
support::endianness getEndian() const override {
return support::little;
}
Error readBytes(uint32_t Offset, uint32_t Size,
ArrayRef<uint8_t> &Buffer) override;
Error readLongestContiguousChunk(uint32_t Offset,
ArrayRef<uint8_t> &Buffer) override;
uint32_t getLength() override;
Error writeBytes(uint32_t Offset, ArrayRef<uint8_t> Buffer) override;
Error commit() override;
const MSFStreamLayout &getStreamLayout() const {
return ReadInterface.getStreamLayout();
}
uint32_t getBlockSize() const { return ReadInterface.getBlockSize(); }
uint32_t getNumBlocks() const { return ReadInterface.getNumBlocks(); }
uint32_t getStreamLength() const { return ReadInterface.getStreamLength(); }
protected:
WritableMappedBlockStream(uint32_t BlockSize,
const MSFStreamLayout &StreamLayout,
WritableBinaryStreamRef MsfData,
BumpPtrAllocator &Allocator);
private:
MappedBlockStream ReadInterface;
WritableBinaryStreamRef WriteInterface;
};
} // end namespace pdb
} // end namespace llvm
#endif // LLVM_DEBUGINFO_MSF_MAPPEDBLOCKSTREAM_H
|
