1 //===- DebugChecksumsSubsection.cpp ---------------------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9
10 #include "llvm/DebugInfo/CodeView/DebugChecksumsSubsection.h"
11 #include "llvm/ADT/ArrayRef.h"
12 #include "llvm/DebugInfo/CodeView/CodeView.h"
13 #include "llvm/DebugInfo/CodeView/DebugStringTableSubsection.h"
14 #include "llvm/Support/BinaryStreamReader.h"
15 #include "llvm/Support/BinaryStreamWriter.h"
16 #include "llvm/Support/Endian.h"
17 #include "llvm/Support/Error.h"
18 #include "llvm/Support/MathExtras.h"
19 #include <cassert>
20 #include <cstdint>
21 #include <cstring>
22
23 using namespace llvm;
24 using namespace llvm::codeview;
25
26 struct FileChecksumEntryHeader {
27 using ulittle32_t = support::ulittle32_t;
28
29 ulittle32_t FileNameOffset; // Byte offset of filename in global string table.
30 uint8_t ChecksumSize; // Number of bytes of checksum.
31 uint8_t ChecksumKind; // FileChecksumKind
32 // Checksum bytes follow.
33 };
34
35 Error VarStreamArrayExtractor<FileChecksumEntry>::
operator ()(BinaryStreamRef Stream,uint32_t & Len,FileChecksumEntry & Item)36 operator()(BinaryStreamRef Stream, uint32_t &Len, FileChecksumEntry &Item) {
37 BinaryStreamReader Reader(Stream);
38
39 const FileChecksumEntryHeader *Header;
40 if (auto EC = Reader.readObject(Header))
41 return EC;
42
43 Item.FileNameOffset = Header->FileNameOffset;
44 Item.Kind = static_cast<FileChecksumKind>(Header->ChecksumKind);
45 if (auto EC = Reader.readBytes(Item.Checksum, Header->ChecksumSize))
46 return EC;
47
48 Len = alignTo(Header->ChecksumSize + sizeof(FileChecksumEntryHeader), 4);
49 return Error::success();
50 }
51
initialize(BinaryStreamReader Reader)52 Error DebugChecksumsSubsectionRef::initialize(BinaryStreamReader Reader) {
53 if (auto EC = Reader.readArray(Checksums, Reader.bytesRemaining()))
54 return EC;
55
56 return Error::success();
57 }
58
initialize(BinaryStreamRef Section)59 Error DebugChecksumsSubsectionRef::initialize(BinaryStreamRef Section) {
60 BinaryStreamReader Reader(Section);
61 return initialize(Reader);
62 }
63
DebugChecksumsSubsection(DebugStringTableSubsection & Strings)64 DebugChecksumsSubsection::DebugChecksumsSubsection(
65 DebugStringTableSubsection &Strings)
66 : DebugSubsection(DebugSubsectionKind::FileChecksums), Strings(Strings) {}
67
addChecksum(StringRef FileName,FileChecksumKind Kind,ArrayRef<uint8_t> Bytes)68 void DebugChecksumsSubsection::addChecksum(StringRef FileName,
69 FileChecksumKind Kind,
70 ArrayRef<uint8_t> Bytes) {
71 FileChecksumEntry Entry;
72 if (!Bytes.empty()) {
73 uint8_t *Copy = Storage.Allocate<uint8_t>(Bytes.size());
74 ::memcpy(Copy, Bytes.data(), Bytes.size());
75 Entry.Checksum = makeArrayRef(Copy, Bytes.size());
76 }
77
78 Entry.FileNameOffset = Strings.insert(FileName);
79 Entry.Kind = Kind;
80 Checksums.push_back(Entry);
81
82 // This maps the offset of this string in the string table to the offset
83 // of this checksum entry in the checksum buffer.
84 OffsetMap[Entry.FileNameOffset] = SerializedSize;
85 assert(SerializedSize % 4 == 0);
86
87 uint32_t Len = alignTo(sizeof(FileChecksumEntryHeader) + Bytes.size(), 4);
88 SerializedSize += Len;
89 }
90
calculateSerializedSize() const91 uint32_t DebugChecksumsSubsection::calculateSerializedSize() const {
92 return SerializedSize;
93 }
94
commit(BinaryStreamWriter & Writer) const95 Error DebugChecksumsSubsection::commit(BinaryStreamWriter &Writer) const {
96 for (const auto &FC : Checksums) {
97 FileChecksumEntryHeader Header;
98 Header.ChecksumKind = uint8_t(FC.Kind);
99 Header.ChecksumSize = FC.Checksum.size();
100 Header.FileNameOffset = FC.FileNameOffset;
101 if (auto EC = Writer.writeObject(Header))
102 return EC;
103 if (auto EC = Writer.writeArray(makeArrayRef(FC.Checksum)))
104 return EC;
105 if (auto EC = Writer.padToAlignment(4))
106 return EC;
107 }
108 return Error::success();
109 }
110
mapChecksumOffset(StringRef FileName) const111 uint32_t DebugChecksumsSubsection::mapChecksumOffset(StringRef FileName) const {
112 uint32_t Offset = Strings.getIdForString(FileName);
113 auto Iter = OffsetMap.find(Offset);
114 assert(Iter != OffsetMap.end());
115 return Iter->second;
116 }
117