1 //===-- ObjectFileWasm.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 LLDB_SOURCE_PLUGINS_OBJECTFILE_WASM_OBJECTFILEWASM_H
10 #define LLDB_SOURCE_PLUGINS_OBJECTFILE_WASM_OBJECTFILEWASM_H
11 
12 #include "lldb/Symbol/ObjectFile.h"
13 #include "lldb/Utility/ArchSpec.h"
14 
15 namespace lldb_private {
16 namespace wasm {
17 
18 /// Generic Wasm object file reader.
19 ///
20 /// This class provides a generic wasm32 reader plugin implementing the
21 /// ObjectFile protocol.
22 class ObjectFileWasm : public ObjectFile {
23 public:
24   static void Initialize();
25   static void Terminate();
26 
27   static llvm::StringRef GetPluginNameStatic() { return "wasm"; }
28   static const char *GetPluginDescriptionStatic() {
29     return "WebAssembly object file reader.";
30   }
31 
32   static ObjectFile *
33   CreateInstance(const lldb::ModuleSP &module_sp, lldb::DataBufferSP data_sp,
34                  lldb::offset_t data_offset, const FileSpec *file,
35                  lldb::offset_t file_offset, lldb::offset_t length);
36 
37   static ObjectFile *CreateMemoryInstance(const lldb::ModuleSP &module_sp,
38                                           lldb::WritableDataBufferSP data_sp,
39                                           const lldb::ProcessSP &process_sp,
40                                           lldb::addr_t header_addr);
41 
42   static size_t GetModuleSpecifications(const FileSpec &file,
43                                         lldb::DataBufferSP &data_sp,
44                                         lldb::offset_t data_offset,
45                                         lldb::offset_t file_offset,
46                                         lldb::offset_t length,
47                                         ModuleSpecList &specs);
48 
49   /// PluginInterface protocol.
50   /// \{
51   llvm::StringRef GetPluginName() override { return GetPluginNameStatic(); }
52   /// \}
53 
54   /// LLVM RTTI support
55   /// \{
56   static char ID;
57   bool isA(const void *ClassID) const override {
58     return ClassID == &ID || ObjectFile::isA(ClassID);
59   }
60   static bool classof(const ObjectFile *obj) { return obj->isA(&ID); }
61   /// \}
62 
63   /// ObjectFile Protocol.
64   /// \{
65   bool ParseHeader() override;
66 
67   lldb::ByteOrder GetByteOrder() const override {
68     return m_arch.GetByteOrder();
69   }
70 
71   bool IsExecutable() const override { return false; }
72 
73   uint32_t GetAddressByteSize() const override {
74     return m_arch.GetAddressByteSize();
75   }
76 
77   AddressClass GetAddressClass(lldb::addr_t file_addr) override {
78     return AddressClass::eInvalid;
79   }
80 
81   void ParseSymtab(lldb_private::Symtab &symtab) override;
82 
83   bool IsStripped() override { return !!GetExternalDebugInfoFileSpec(); }
84 
85   void CreateSections(SectionList &unified_section_list) override;
86 
87   void Dump(Stream *s) override;
88 
89   ArchSpec GetArchitecture() override { return m_arch; }
90 
91   UUID GetUUID() override { return m_uuid; }
92 
93   uint32_t GetDependentModules(FileSpecList &files) override { return 0; }
94 
95   Type CalculateType() override { return eTypeSharedLibrary; }
96 
97   Strata CalculateStrata() override { return eStrataUser; }
98 
99   bool SetLoadAddress(lldb_private::Target &target, lldb::addr_t value,
100                       bool value_is_offset) override;
101 
102   lldb_private::Address GetBaseAddress() override {
103     return IsInMemory() ? Address(m_memory_addr) : Address(0);
104   }
105   /// \}
106 
107   /// A Wasm module that has external DWARF debug information should contain a
108   /// custom section named "external_debug_info", whose payload is an UTF-8
109   /// encoded string that points to a Wasm module that contains the debug
110   /// information for this module.
111   llvm::Optional<FileSpec> GetExternalDebugInfoFileSpec();
112 
113 private:
114   ObjectFileWasm(const lldb::ModuleSP &module_sp, lldb::DataBufferSP data_sp,
115                  lldb::offset_t data_offset, const FileSpec *file,
116                  lldb::offset_t offset, lldb::offset_t length);
117   ObjectFileWasm(const lldb::ModuleSP &module_sp,
118                  lldb::WritableDataBufferSP header_data_sp,
119                  const lldb::ProcessSP &process_sp, lldb::addr_t header_addr);
120 
121   /// Wasm section decoding routines.
122   /// \{
123   bool DecodeNextSection(lldb::offset_t *offset_ptr);
124   bool DecodeSections();
125   /// \}
126 
127   /// Read a range of bytes from the Wasm module.
128   DataExtractor ReadImageData(lldb::offset_t offset, uint32_t size);
129 
130   typedef struct section_info {
131     lldb::offset_t offset;
132     uint32_t size;
133     uint32_t id;
134     ConstString name;
135   } section_info_t;
136 
137   /// Wasm section header dump routines.
138   /// \{
139   void DumpSectionHeader(llvm::raw_ostream &ostream, const section_info_t &sh);
140   void DumpSectionHeaders(llvm::raw_ostream &ostream);
141   /// \}
142 
143   std::vector<section_info_t> m_sect_infos;
144   ArchSpec m_arch;
145   UUID m_uuid;
146 };
147 
148 } // namespace wasm
149 } // namespace lldb_private
150 #endif // LLDB_SOURCE_PLUGINS_OBJECTFILE_WASM_OBJECTFILEWASM_H
151