include/llvm/DebugInfo/CodeView/StringsAndChecksums.h

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