1 //===- ModuleDebugStream.cpp - PDB Module Info Stream Access --------------===//
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/PDB/Native/ModuleDebugStream.h"
11 #include "llvm/ADT/iterator_range.h"
12 #include "llvm/DebugInfo/CodeView/CodeView.h"
13 #include "llvm/DebugInfo/CodeView/DebugChecksumsSubsection.h"
14 #include "llvm/DebugInfo/CodeView/SymbolRecord.h"
15 #include "llvm/DebugInfo/PDB/Native/DbiModuleDescriptor.h"
16 #include "llvm/DebugInfo/PDB/Native/RawError.h"
17 #include "llvm/Support/BinaryStreamReader.h"
18 #include "llvm/Support/BinaryStreamRef.h"
19 #include "llvm/Support/Error.h"
20 #include <algorithm>
21 #include <cstdint>
22 
23 using namespace llvm;
24 using namespace llvm::codeview;
25 using namespace llvm::msf;
26 using namespace llvm::pdb;
27 
28 ModuleDebugStreamRef::ModuleDebugStreamRef(
29     const DbiModuleDescriptor &Module,
30     std::unique_ptr<MappedBlockStream> Stream)
31     : Mod(Module), Stream(std::move(Stream)) {}
32 
33 ModuleDebugStreamRef::~ModuleDebugStreamRef() = default;
34 
35 Error ModuleDebugStreamRef::reload() {
36   BinaryStreamReader Reader(*Stream);
37 
38   uint32_t SymbolSize = Mod.getSymbolDebugInfoByteSize();
39   uint32_t C11Size = Mod.getC11LineInfoByteSize();
40   uint32_t C13Size = Mod.getC13LineInfoByteSize();
41 
42   if (C11Size > 0 && C13Size > 0)
43     return make_error<RawError>(raw_error_code::corrupt_file,
44                                 "Module has both C11 and C13 line info");
45 
46   BinaryStreamRef S;
47 
48   if (auto EC = Reader.readInteger(Signature))
49     return EC;
50   if (auto EC = Reader.readSubstream(SymbolsSubstream, SymbolSize - 4))
51     return EC;
52   if (auto EC = Reader.readSubstream(C11LinesSubstream, C11Size))
53     return EC;
54   if (auto EC = Reader.readSubstream(C13LinesSubstream, C13Size))
55     return EC;
56 
57   BinaryStreamReader SymbolReader(SymbolsSubstream.StreamData);
58   if (auto EC =
59           SymbolReader.readArray(SymbolArray, SymbolReader.bytesRemaining()))
60     return EC;
61 
62   BinaryStreamReader SubsectionsReader(C13LinesSubstream.StreamData);
63   if (auto EC = SubsectionsReader.readArray(Subsections,
64                                             SubsectionsReader.bytesRemaining()))
65     return EC;
66 
67   uint32_t GlobalRefsSize;
68   if (auto EC = Reader.readInteger(GlobalRefsSize))
69     return EC;
70   if (auto EC = Reader.readSubstream(GlobalRefsSubstream, GlobalRefsSize))
71     return EC;
72   if (Reader.bytesRemaining() > 0)
73     return make_error<RawError>(raw_error_code::corrupt_file,
74                                 "Unexpected bytes in module stream.");
75 
76   return Error::success();
77 }
78 
79 BinarySubstreamRef ModuleDebugStreamRef::getSymbolsSubstream() const {
80   return SymbolsSubstream;
81 }
82 
83 BinarySubstreamRef ModuleDebugStreamRef::getC11LinesSubstream() const {
84   return C11LinesSubstream;
85 }
86 
87 BinarySubstreamRef ModuleDebugStreamRef::getC13LinesSubstream() const {
88   return C13LinesSubstream;
89 }
90 
91 BinarySubstreamRef ModuleDebugStreamRef::getGlobalRefsSubstream() const {
92   return GlobalRefsSubstream;
93 }
94 
95 iterator_range<codeview::CVSymbolArray::Iterator>
96 ModuleDebugStreamRef::symbols(bool *HadError) const {
97   return make_range(SymbolArray.begin(HadError), SymbolArray.end());
98 }
99 
100 CVSymbol ModuleDebugStreamRef::readSymbolAtOffset(uint32_t Offset) const {
101   // Offsets include the size of the 4-byte magic at the beginning, but lookup
102   // doesn't take that into account, so subtract it here.
103   auto Iter = SymbolArray.at(Offset - 4);
104   assert(Iter != SymbolArray.end());
105   return *Iter;
106 }
107 
108 iterator_range<ModuleDebugStreamRef::DebugSubsectionIterator>
109 ModuleDebugStreamRef::subsections() const {
110   return make_range(Subsections.begin(), Subsections.end());
111 }
112 
113 bool ModuleDebugStreamRef::hasDebugSubsections() const {
114   return !C13LinesSubstream.empty();
115 }
116 
117 Error ModuleDebugStreamRef::commit() { return Error::success(); }
118 
119 Expected<codeview::DebugChecksumsSubsectionRef>
120 ModuleDebugStreamRef::findChecksumsSubsection() const {
121   codeview::DebugChecksumsSubsectionRef Result;
122   for (const auto &SS : subsections()) {
123     if (SS.kind() != DebugSubsectionKind::FileChecksums)
124       continue;
125 
126     if (auto EC = Result.initialize(SS.getRecordData()))
127       return std::move(EC);
128     return Result;
129   }
130   return Result;
131 }
132