1 //===-- DYLDRendezvous.h ----------------------------------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 #ifndef liblldb_Rendezvous_H_
11 #define liblldb_Rendezvous_H_
18 // Other libraries and framework includes
19 #include "lldb/Utility/FileSpec.h"
20 #include "lldb/lldb-defines.h"
21 #include "lldb/lldb-types.h"
23 #include "lldb/Core/LoadedModuleInfoList.h"
25 using lldb_private::LoadedModuleInfoList;
27 namespace lldb_private {
31 /// @class DYLDRendezvous
32 /// Interface to the runtime linker.
34 /// A structure is present in a processes memory space which is updated by the
35 /// runtime liker each time a module is loaded or unloaded. This class
36 /// provides an interface to this structure and maintains a consistent
37 /// snapshot of the currently loaded modules.
38 class DYLDRendezvous {
40 // This structure is used to hold the contents of the debug rendezvous
41 // information (struct r_debug) as found in the inferiors memory. Note that
42 // the layout of this struct is not binary compatible, it is simply large
43 // enough to hold the information on both 32 and 64 bit platforms.
46 lldb::addr_t map_addr;
51 Rendezvous() : version(0), map_addr(0), brk(0), state(0), ldbase(0) {}
55 // Various metadata supplied by the inferior's threading library to describe
56 // the per-thread state.
58 bool valid; // whether we read valid metadata
59 uint32_t dtv_offset; // offset of DTV pointer within pthread
60 uint32_t dtv_slot_size; // size of one DTV slot
61 uint32_t modid_offset; // offset of module ID within link_map
62 uint32_t tls_offset; // offset of TLS pointer within DTV slot
65 DYLDRendezvous(lldb_private::Process *process);
67 /// Update the internal snapshot of runtime linker rendezvous and recompute
68 /// the currently loaded modules.
70 /// This method should be called once one start up, then once each time the
71 /// runtime linker enters the function given by GetBreakAddress().
73 /// @returns true on success and false on failure.
75 /// @see GetBreakAddress().
78 /// @returns true if this rendezvous has been located in the inferiors
79 /// address space and false otherwise.
82 /// @returns the address of the rendezvous structure in the inferiors
84 lldb::addr_t GetRendezvousAddress() const { return m_rendezvous_addr; }
86 /// @returns the version of the rendezvous protocol being used.
87 uint64_t GetVersion() const { return m_current.version; }
89 /// @returns address in the inferiors address space containing the linked
90 /// list of shared object descriptors.
91 lldb::addr_t GetLinkMapAddress() const { return m_current.map_addr; }
93 /// A breakpoint should be set at this address and Resolve called on each
96 /// @returns the address of a function called by the runtime linker each
97 /// time a module is loaded/unloaded, or about to be loaded/unloaded.
100 lldb::addr_t GetBreakAddress() const { return m_current.brk; }
102 /// Returns the current state of the rendezvous structure.
103 uint64_t GetState() const { return m_current.state; }
105 /// @returns the base address of the runtime linker in the inferiors address
107 lldb::addr_t GetLDBase() const { return m_current.ldbase; }
109 /// @returns the thread layout metadata from the inferiors thread library.
110 const ThreadInfo &GetThreadInfo();
112 /// @returns true if modules have been loaded into the inferior since the
113 /// last call to Resolve().
114 bool ModulesDidLoad() const { return !m_added_soentries.empty(); }
116 /// @returns true if modules have been unloaded from the inferior since the
117 /// last call to Resolve().
118 bool ModulesDidUnload() const { return !m_removed_soentries.empty(); }
120 void DumpToLog(lldb_private::Log *log) const;
122 /// Constants describing the state of the rendezvous.
125 enum RendezvousState { eConsistent, eAdd, eDelete };
127 /// Structure representing the shared objects currently loaded into the
128 /// inferior process.
130 /// This object is a rough analogue to the struct link_map object which
131 /// actually lives in the inferiors memory.
133 lldb::addr_t link_addr; ///< Address of this link_map.
134 lldb::addr_t base_addr; ///< Base address of the loaded object.
135 lldb::addr_t path_addr; ///< String naming the shared object.
136 lldb::addr_t dyn_addr; ///< Dynamic section of shared object.
137 lldb::addr_t next; ///< Address of next so_entry.
138 lldb::addr_t prev; ///< Address of previous so_entry.
139 lldb_private::FileSpec file_spec; ///< File spec of shared object.
141 SOEntry() { clear(); }
143 bool operator==(const SOEntry &entry) {
144 return file_spec == entry.file_spec;
159 typedef std::list<SOEntry> SOEntryList;
162 typedef SOEntryList::const_iterator iterator;
164 /// Iterators over all currently loaded modules.
165 iterator begin() const { return m_soentries.begin(); }
166 iterator end() const { return m_soentries.end(); }
168 /// Iterators over all modules loaded into the inferior since the last call
170 iterator loaded_begin() const { return m_added_soentries.begin(); }
171 iterator loaded_end() const { return m_added_soentries.end(); }
173 /// Iterators over all modules unloaded from the inferior since the last
174 /// call to Resolve().
175 iterator unloaded_begin() const { return m_removed_soentries.begin(); }
176 iterator unloaded_end() const { return m_removed_soentries.end(); }
179 lldb_private::Process *m_process;
181 // Cached copy of executable file spec
182 lldb_private::FileSpec m_exe_file_spec;
184 /// Location of the r_debug structure in the inferiors address space.
185 lldb::addr_t m_rendezvous_addr;
187 /// Current and previous snapshots of the rendezvous structure.
188 Rendezvous m_current;
189 Rendezvous m_previous;
191 /// List of currently loaded SO modules
192 LoadedModuleInfoList m_loaded_modules;
194 /// List of SOEntry objects corresponding to the current link map state.
195 SOEntryList m_soentries;
197 /// List of SOEntry's added to the link map since the last call to
199 SOEntryList m_added_soentries;
201 /// List of SOEntry's removed from the link map since the last call to
203 SOEntryList m_removed_soentries;
205 /// Threading metadata read from the inferior.
206 ThreadInfo m_thread_info;
208 /// Reads an unsigned integer of @p size bytes from the inferior's address
209 /// space starting at @p addr.
211 /// @returns addr + size if the read was successful and false otherwise.
212 lldb::addr_t ReadWord(lldb::addr_t addr, uint64_t *dst, size_t size);
214 /// Reads an address from the inferior's address space starting at @p addr.
216 /// @returns addr + target address size if the read was successful and
218 lldb::addr_t ReadPointer(lldb::addr_t addr, lldb::addr_t *dst);
220 /// Reads a null-terminated C string from the memory location starting at @p
222 std::string ReadStringFromMemory(lldb::addr_t addr);
224 /// Reads an SOEntry starting at @p addr.
225 bool ReadSOEntryFromMemory(lldb::addr_t addr, SOEntry &entry);
227 /// Updates the current set of SOEntries, the set of added entries, and the
228 /// set of removed entries.
229 bool UpdateSOEntries(bool fromRemote = false);
231 bool FillSOEntryFromModuleInfo(
232 LoadedModuleInfoList::LoadedModuleInfo const &modInfo, SOEntry &entry);
234 bool SaveSOEntriesFromRemote(LoadedModuleInfoList &module_list);
236 bool AddSOEntriesFromRemote(LoadedModuleInfoList &module_list);
238 bool RemoveSOEntriesFromRemote(LoadedModuleInfoList &module_list);
242 bool RemoveSOEntries();
244 void UpdateBaseAddrIfNecessary(SOEntry &entry, std::string const &file_path);
246 bool SOEntryIsMainExecutable(const SOEntry &entry);
248 /// Reads the current list of shared objects according to the link map
249 /// supplied by the runtime linker.
250 bool TakeSnapshot(SOEntryList &entry_list);
252 enum PThreadField { eSize, eNElem, eOffset };
254 bool FindMetadata(const char *name, PThreadField field, uint32_t &value);