1 //===- DebugStringTableSubsection.h - CodeView String Table -----*- 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_DEBUGSTRINGTABLESUBSECTION_H
10 #define LLVM_DEBUGINFO_CODEVIEW_DEBUGSTRINGTABLESUBSECTION_H
11 
12 #include "llvm/ADT/DenseMap.h"
13 #include "llvm/ADT/StringMap.h"
14 #include "llvm/ADT/StringRef.h"
15 #include "llvm/DebugInfo/CodeView/CodeView.h"
16 #include "llvm/DebugInfo/CodeView/DebugSubsection.h"
17 #include "llvm/Support/BinaryStreamRef.h"
18 #include "llvm/Support/Error.h"
19 #include <cstdint>
20 
21 namespace llvm {
22 
23 class BinaryStreamReader;
24 
25 namespace codeview {
26 
27 /// Represents a read-only view of a CodeView string table.  This is a very
28 /// simple flat buffer consisting of null-terminated strings, where strings
29 /// are retrieved by their offset in the buffer.  DebugStringTableSubsectionRef
30 /// does not own the underlying storage for the buffer.
31 class DebugStringTableSubsectionRef : public DebugSubsectionRef {
32 public:
33   DebugStringTableSubsectionRef();
34 
classof(const DebugSubsectionRef * S)35   static bool classof(const DebugSubsectionRef *S) {
36     return S->kind() == DebugSubsectionKind::StringTable;
37   }
38 
39   Error initialize(BinaryStreamRef Contents);
40   Error initialize(BinaryStreamReader &Reader);
41 
42   Expected<StringRef> getString(uint32_t Offset) const;
43 
valid()44   bool valid() const { return Stream.valid(); }
45 
getBuffer()46   BinaryStreamRef getBuffer() const { return Stream; }
47 
48 private:
49   BinaryStreamRef Stream;
50 };
51 
52 /// Represents a read-write view of a CodeView string table.
53 /// DebugStringTableSubsection owns the underlying storage for the table, and is
54 /// capable of serializing the string table into a format understood by
55 /// DebugStringTableSubsectionRef.
56 class DebugStringTableSubsection : public DebugSubsection {
57 public:
58   DebugStringTableSubsection();
59 
classof(const DebugSubsection * S)60   static bool classof(const DebugSubsection *S) {
61     return S->kind() == DebugSubsectionKind::StringTable;
62   }
63 
64   // If string S does not exist in the string table, insert it.
65   // Returns the ID for S.
66   uint32_t insert(StringRef S);
67 
68   // Return the ID for string S.  Assumes S exists in the table.
69   uint32_t getIdForString(StringRef S) const;
70 
71   StringRef getStringForId(uint32_t Id) const;
72 
73   uint32_t calculateSerializedSize() const override;
74   Error commit(BinaryStreamWriter &Writer) const override;
75 
76   uint32_t size() const;
77 
begin()78   StringMap<uint32_t>::const_iterator begin() const {
79     return StringToId.begin();
80   }
81 
end()82   StringMap<uint32_t>::const_iterator end() const { return StringToId.end(); }
83 
84   std::vector<uint32_t> sortedIds() const;
85 
86 private:
87   DenseMap<uint32_t, StringRef> IdToString;
88   StringMap<uint32_t> StringToId;
89   uint32_t StringSize = 1;
90 };
91 
92 } // end namespace codeview
93 
94 } // end namespace llvm
95 
96 #endif // LLVM_DEBUGINFO_CODEVIEW_DEBUGSTRINGTABLESUBSECTION_H
97