1 //===-- ProcessElfCore.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 // Notes about Linux Process core dumps:
8 //  1) Linux core dump is stored as ELF file.
9 //  2) The ELF file's PT_NOTE and PT_LOAD segments describes the program's
10 //     address space and thread contexts.
11 //  3) PT_NOTE segment contains note entries which describes a thread context.
12 //  4) PT_LOAD segment describes a valid contiguous range of process address
13 //     space.
14 //===----------------------------------------------------------------------===//
15 
16 #ifndef LLDB_SOURCE_PLUGINS_PROCESS_ELF_CORE_PROCESSELFCORE_H
17 #define LLDB_SOURCE_PLUGINS_PROCESS_ELF_CORE_PROCESSELFCORE_H
18 
19 #include <list>
20 #include <vector>
21 
22 #include "lldb/Target/PostMortemProcess.h"
23 #include "lldb/Utility/ConstString.h"
24 #include "lldb/Utility/Status.h"
25 
26 #include "Plugins/ObjectFile/ELF/ELFHeader.h"
27 #include "Plugins/Process/elf-core/RegisterUtilities.h"
28 
29 struct ThreadData;
30 
31 class ProcessElfCore : public lldb_private::PostMortemProcess {
32 public:
33   // Constructors and Destructors
34   static lldb::ProcessSP
35   CreateInstance(lldb::TargetSP target_sp, lldb::ListenerSP listener_sp,
36                  const lldb_private::FileSpec *crash_file_path,
37                  bool can_connect);
38 
39   static void Initialize();
40 
41   static void Terminate();
42 
43   static lldb_private::ConstString GetPluginNameStatic();
44 
45   static const char *GetPluginDescriptionStatic();
46 
47   // Constructors and Destructors
48   ProcessElfCore(lldb::TargetSP target_sp, lldb::ListenerSP listener_sp,
49                  const lldb_private::FileSpec &core_file);
50 
51   ~ProcessElfCore() override;
52 
53   // Check if a given Process
54   bool CanDebug(lldb::TargetSP target_sp,
55                 bool plugin_specified_by_name) override;
56 
57   // Creating a new process, or attaching to an existing one
58   lldb_private::Status DoLoadCore() override;
59 
60   lldb_private::DynamicLoader *GetDynamicLoader() override;
61 
62   // PluginInterface protocol
63   llvm::StringRef GetPluginName() override {
64     return GetPluginNameStatic().GetStringRef();
65   }
66 
67   // Process Control
68   lldb_private::Status DoDestroy() override;
69 
70   void RefreshStateAfterStop() override;
71 
72   lldb_private::Status WillResume() override {
73     lldb_private::Status error;
74     error.SetErrorStringWithFormatv(
75         "error: {0} does not support resuming processes", GetPluginName());
76     return error;
77   }
78 
79   // Process Queries
80   bool IsAlive() override;
81 
82   bool WarnBeforeDetach() const override { return false; }
83 
84   // Process Memory
85   size_t ReadMemory(lldb::addr_t addr, void *buf, size_t size,
86                     lldb_private::Status &error) override;
87 
88   size_t DoReadMemory(lldb::addr_t addr, void *buf, size_t size,
89                       lldb_private::Status &error) override;
90 
91   lldb_private::Status
92   GetMemoryRegionInfo(lldb::addr_t load_addr,
93                       lldb_private::MemoryRegionInfo &region_info) override;
94 
95   lldb::addr_t GetImageInfoAddress() override;
96 
97   lldb_private::ArchSpec GetArchitecture();
98 
99   // Returns AUXV structure found in the core file
100   lldb_private::DataExtractor GetAuxvData() override;
101 
102   bool GetProcessInfo(lldb_private::ProcessInstanceInfo &info) override;
103 
104 protected:
105   void Clear();
106 
107   bool DoUpdateThreadList(lldb_private::ThreadList &old_thread_list,
108                           lldb_private::ThreadList &new_thread_list) override;
109 
110 private:
111   struct NT_FILE_Entry {
112     lldb::addr_t start;
113     lldb::addr_t end;
114     lldb::addr_t file_ofs;
115     lldb_private::ConstString path;
116   };
117 
118   // For ProcessElfCore only
119   typedef lldb_private::Range<lldb::addr_t, lldb::addr_t> FileRange;
120   typedef lldb_private::RangeDataVector<lldb::addr_t, lldb::addr_t, FileRange>
121       VMRangeToFileOffset;
122   typedef lldb_private::RangeDataVector<lldb::addr_t, lldb::addr_t, uint32_t>
123       VMRangeToPermissions;
124 
125   lldb::ModuleSP m_core_module_sp;
126   lldb_private::FileSpec m_core_file;
127   std::string m_dyld_plugin_name;
128 
129   // True if m_thread_contexts contains valid entries
130   bool m_thread_data_valid = false;
131 
132   // Contain thread data read from NOTE segments
133   std::vector<ThreadData> m_thread_data;
134 
135   // AUXV structure found from the NOTE segment
136   lldb_private::DataExtractor m_auxv;
137 
138   // Address ranges found in the core
139   VMRangeToFileOffset m_core_aranges;
140 
141   // Permissions for all ranges
142   VMRangeToPermissions m_core_range_infos;
143 
144   // NT_FILE entries found from the NOTE segment
145   std::vector<NT_FILE_Entry> m_nt_file_entries;
146 
147   // Parse thread(s) data structures(prstatus, prpsinfo) from given NOTE segment
148   llvm::Error ParseThreadContextsFromNoteSegment(
149       const elf::ELFProgramHeader &segment_header,
150       const lldb_private::DataExtractor &segment_data);
151 
152   // Returns number of thread contexts stored in the core file
153   uint32_t GetNumThreadContexts();
154 
155   // Parse a contiguous address range of the process from LOAD segment
156   lldb::addr_t
157   AddAddressRangeFromLoadSegment(const elf::ELFProgramHeader &header);
158 
159   llvm::Expected<std::vector<lldb_private::CoreNote>>
160   parseSegment(const lldb_private::DataExtractor &segment);
161   llvm::Error parseFreeBSDNotes(llvm::ArrayRef<lldb_private::CoreNote> notes);
162   llvm::Error parseNetBSDNotes(llvm::ArrayRef<lldb_private::CoreNote> notes);
163   llvm::Error parseOpenBSDNotes(llvm::ArrayRef<lldb_private::CoreNote> notes);
164   llvm::Error parseLinuxNotes(llvm::ArrayRef<lldb_private::CoreNote> notes);
165 };
166 
167 #endif // LLDB_SOURCE_PLUGINS_PROCESS_ELF_CORE_PROCESSELFCORE_H
168