1 //===- StringsAndChecksums.h ------------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #ifndef LLVM_DEBUGINFO_CODEVIEW_STRINGSANDCHECKSUMS_H
10 #define LLVM_DEBUGINFO_CODEVIEW_STRINGSANDCHECKSUMS_H
11 
12 #include "llvm/DebugInfo/CodeView/CodeView.h"
13 #include "llvm/DebugInfo/CodeView/DebugSubsectionRecord.h"
14 #include <memory>
15 
16 namespace llvm {
17 namespace codeview {
18 class DebugChecksumsSubsection;
19 class DebugChecksumsSubsectionRef;
20 class DebugStringTableSubsection;
21 class DebugStringTableSubsectionRef;
22 
23 class StringsAndChecksumsRef {
24 public:
25   // If no subsections are known about initially, we find as much as we can.
26   StringsAndChecksumsRef();
27 
28   // If only a string table subsection is given, we find a checksums subsection.
29   explicit StringsAndChecksumsRef(const DebugStringTableSubsectionRef &Strings);
30 
31   // If both subsections are given, we don't need to find anything.
32   StringsAndChecksumsRef(const DebugStringTableSubsectionRef &Strings,
33                          const DebugChecksumsSubsectionRef &Checksums);
34 
35   void setStrings(const DebugStringTableSubsectionRef &Strings);
36   void setChecksums(const DebugChecksumsSubsectionRef &CS);
37 
38   void reset();
39   void resetStrings();
40   void resetChecksums();
41 
initialize(T && FragmentRange)42   template <typename T> void initialize(T &&FragmentRange) {
43     for (const DebugSubsectionRecord &R : FragmentRange) {
44       if (Strings && Checksums)
45         return;
46       if (R.kind() == DebugSubsectionKind::FileChecksums) {
47         initializeChecksums(R);
48         continue;
49       }
50       if (R.kind() == DebugSubsectionKind::StringTable && !Strings) {
51         // While in practice we should never encounter a string table even
52         // though the string table is already initialized, in theory it's
53         // possible.  PDBs are supposed to have one global string table and
54         // then this subsection should not appear.  Whereas object files are
55         // supposed to have this subsection appear exactly once.  However,
56         // for testing purposes it's nice to be able to test this subsection
57         // independently of one format or the other, so for some tests we
58         // manually construct a PDB that contains this subsection in addition
59         // to a global string table.
60         initializeStrings(R);
61         continue;
62       }
63     }
64   }
65 
strings()66   const DebugStringTableSubsectionRef &strings() const { return *Strings; }
checksums()67   const DebugChecksumsSubsectionRef &checksums() const { return *Checksums; }
68 
hasStrings()69   bool hasStrings() const { return Strings != nullptr; }
hasChecksums()70   bool hasChecksums() const { return Checksums != nullptr; }
71 
72 private:
73   void initializeStrings(const DebugSubsectionRecord &SR);
74   void initializeChecksums(const DebugSubsectionRecord &FCR);
75 
76   std::shared_ptr<DebugStringTableSubsectionRef> OwnedStrings;
77   std::shared_ptr<DebugChecksumsSubsectionRef> OwnedChecksums;
78 
79   const DebugStringTableSubsectionRef *Strings = nullptr;
80   const DebugChecksumsSubsectionRef *Checksums = nullptr;
81 };
82 
83 class StringsAndChecksums {
84 public:
85   using StringsPtr = std::shared_ptr<DebugStringTableSubsection>;
86   using ChecksumsPtr = std::shared_ptr<DebugChecksumsSubsection>;
87 
88   // If no subsections are known about initially, we find as much as we can.
89   StringsAndChecksums() = default;
90 
setStrings(const StringsPtr & SP)91   void setStrings(const StringsPtr &SP) { Strings = SP; }
setChecksums(const ChecksumsPtr & CP)92   void setChecksums(const ChecksumsPtr &CP) { Checksums = CP; }
93 
strings()94   const StringsPtr &strings() const { return Strings; }
checksums()95   const ChecksumsPtr &checksums() const { return Checksums; }
96 
hasStrings()97   bool hasStrings() const { return Strings != nullptr; }
hasChecksums()98   bool hasChecksums() const { return Checksums != nullptr; }
99 
100 private:
101   StringsPtr Strings;
102   ChecksumsPtr Checksums;
103 };
104 
105 } // end namespace codeview
106 } // end namespace llvm
107 
108 #endif // LLVM_DEBUGINFO_CODEVIEW_STRINGSANDCHECKSUMS_H
109