1 //===-- NativeProcessLinux.h ---------------------------------- -*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #ifndef liblldb_NativeProcessLinux_H_
11 #define liblldb_NativeProcessLinux_H_
12 
13 #include <csignal>
14 #include <unordered_set>
15 
16 #include "lldb/Host/Debug.h"
17 #include "lldb/Host/HostThread.h"
18 #include "lldb/Host/linux/Support.h"
19 #include "lldb/Target/MemoryRegionInfo.h"
20 #include "lldb/Utility/ArchSpec.h"
21 #include "lldb/Utility/FileSpec.h"
22 #include "lldb/lldb-types.h"
23 
24 #include "NativeThreadLinux.h"
25 #include "ProcessorTrace.h"
26 #include "lldb/Host/common/NativeProcessProtocol.h"
27 
28 namespace lldb_private {
29 class Status;
30 class Scalar;
31 
32 namespace process_linux {
33 /// @class NativeProcessLinux
34 /// Manages communication with the inferior (debugee) process.
35 ///
36 /// Upon construction, this class prepares and launches an inferior process
37 /// for debugging.
38 ///
39 /// Changes in the inferior process state are broadcasted.
40 class NativeProcessLinux : public NativeProcessProtocol {
41 public:
42   class Factory : public NativeProcessProtocol::Factory {
43   public:
44     llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
45     Launch(ProcessLaunchInfo &launch_info, NativeDelegate &native_delegate,
46            MainLoop &mainloop) const override;
47 
48     llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
49     Attach(lldb::pid_t pid, NativeDelegate &native_delegate,
50            MainLoop &mainloop) const override;
51   };
52 
53   // ---------------------------------------------------------------------
54   // NativeProcessProtocol Interface
55   // ---------------------------------------------------------------------
56   Status Resume(const ResumeActionList &resume_actions) override;
57 
58   Status Halt() override;
59 
60   Status Detach() override;
61 
62   Status Signal(int signo) override;
63 
64   Status Interrupt() override;
65 
66   Status Kill() override;
67 
68   Status GetMemoryRegionInfo(lldb::addr_t load_addr,
69                              MemoryRegionInfo &range_info) override;
70 
71   Status ReadMemory(lldb::addr_t addr, void *buf, size_t size,
72                     size_t &bytes_read) override;
73 
74   Status ReadMemoryWithoutTrap(lldb::addr_t addr, void *buf, size_t size,
75                                size_t &bytes_read) override;
76 
77   Status WriteMemory(lldb::addr_t addr, const void *buf, size_t size,
78                      size_t &bytes_written) override;
79 
80   Status AllocateMemory(size_t size, uint32_t permissions,
81                         lldb::addr_t &addr) override;
82 
83   Status DeallocateMemory(lldb::addr_t addr) override;
84 
85   lldb::addr_t GetSharedLibraryInfoAddress() override;
86 
87   size_t UpdateThreads() override;
88 
89   const ArchSpec &GetArchitecture() const override { return m_arch; }
90 
91   Status SetBreakpoint(lldb::addr_t addr, uint32_t size,
92                        bool hardware) override;
93 
94   Status RemoveBreakpoint(lldb::addr_t addr, bool hardware = false) override;
95 
96   void DoStopIDBumped(uint32_t newBumpId) override;
97 
98   Status GetLoadedModuleFileSpec(const char *module_path,
99                                  FileSpec &file_spec) override;
100 
101   Status GetFileLoadAddress(const llvm::StringRef &file_name,
102                             lldb::addr_t &load_addr) override;
103 
104   NativeThreadLinux *GetThreadByID(lldb::tid_t id);
105 
106   llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
107   GetAuxvData() const override {
108     return getProcFile(GetID(), "auxv");
109   }
110 
111   lldb::user_id_t StartTrace(const TraceOptions &config,
112                              Status &error) override;
113 
114   Status StopTrace(lldb::user_id_t traceid,
115                    lldb::tid_t thread) override;
116 
117   Status GetData(lldb::user_id_t traceid, lldb::tid_t thread,
118                  llvm::MutableArrayRef<uint8_t> &buffer,
119                  size_t offset = 0) override;
120 
121   Status GetMetaData(lldb::user_id_t traceid, lldb::tid_t thread,
122                      llvm::MutableArrayRef<uint8_t> &buffer,
123                      size_t offset = 0) override;
124 
125   Status GetTraceConfig(lldb::user_id_t traceid, TraceOptions &config) override;
126 
127   // ---------------------------------------------------------------------
128   // Interface used by NativeRegisterContext-derived classes.
129   // ---------------------------------------------------------------------
130   static Status PtraceWrapper(int req, lldb::pid_t pid, void *addr = nullptr,
131                               void *data = nullptr, size_t data_size = 0,
132                               long *result = nullptr);
133 
134   bool SupportHardwareSingleStepping() const;
135 
136 protected:
137   // ---------------------------------------------------------------------
138   // NativeProcessProtocol protected interface
139   // ---------------------------------------------------------------------
140   Status
141   GetSoftwareBreakpointTrapOpcode(size_t trap_opcode_size_hint,
142                                   size_t &actual_opcode_size,
143                                   const uint8_t *&trap_opcode_bytes) override;
144 
145 private:
146   MainLoop::SignalHandleUP m_sigchld_handle;
147   ArchSpec m_arch;
148 
149   LazyBool m_supports_mem_region = eLazyBoolCalculate;
150   std::vector<std::pair<MemoryRegionInfo, FileSpec>> m_mem_region_cache;
151 
152   lldb::tid_t m_pending_notification_tid = LLDB_INVALID_THREAD_ID;
153 
154   // List of thread ids stepping with a breakpoint with the address of
155   // the relevan breakpoint
156   std::map<lldb::tid_t, lldb::addr_t> m_threads_stepping_with_breakpoint;
157 
158   // ---------------------------------------------------------------------
159   // Private Instance Methods
160   // ---------------------------------------------------------------------
161   NativeProcessLinux(::pid_t pid, int terminal_fd, NativeDelegate &delegate,
162                      const ArchSpec &arch, MainLoop &mainloop,
163                      llvm::ArrayRef<::pid_t> tids);
164 
165   // Returns a list of process threads that we have attached to.
166   static llvm::Expected<std::vector<::pid_t>> Attach(::pid_t pid);
167 
168   static Status SetDefaultPtraceOpts(const lldb::pid_t);
169 
170   void MonitorCallback(lldb::pid_t pid, bool exited, WaitStatus status);
171 
172   void WaitForNewThread(::pid_t tid);
173 
174   void MonitorSIGTRAP(const siginfo_t &info, NativeThreadLinux &thread);
175 
176   void MonitorTrace(NativeThreadLinux &thread);
177 
178   void MonitorBreakpoint(NativeThreadLinux &thread);
179 
180   void MonitorWatchpoint(NativeThreadLinux &thread, uint32_t wp_index);
181 
182   void MonitorSignal(const siginfo_t &info, NativeThreadLinux &thread,
183                      bool exited);
184 
185   Status SetupSoftwareSingleStepping(NativeThreadLinux &thread);
186 
187 #if 0
188         static ::ProcessMessage::CrashReason
189         GetCrashReasonForSIGSEGV(const siginfo_t *info);
190 
191         static ::ProcessMessage::CrashReason
192         GetCrashReasonForSIGILL(const siginfo_t *info);
193 
194         static ::ProcessMessage::CrashReason
195         GetCrashReasonForSIGFPE(const siginfo_t *info);
196 
197         static ::ProcessMessage::CrashReason
198         GetCrashReasonForSIGBUS(const siginfo_t *info);
199 #endif
200 
201   bool HasThreadNoLock(lldb::tid_t thread_id);
202 
203   bool StopTrackingThread(lldb::tid_t thread_id);
204 
205   NativeThreadLinux &AddThread(lldb::tid_t thread_id);
206 
207   Status GetSoftwareBreakpointPCOffset(uint32_t &actual_opcode_size);
208 
209   Status FixupBreakpointPCAsNeeded(NativeThreadLinux &thread);
210 
211   /// Writes a siginfo_t structure corresponding to the given thread ID to the
212   /// memory region pointed to by @p siginfo.
213   Status GetSignalInfo(lldb::tid_t tid, void *siginfo);
214 
215   /// Writes the raw event message code (vis-a-vis PTRACE_GETEVENTMSG)
216   /// corresponding to the given thread ID to the memory pointed to by @p
217   /// message.
218   Status GetEventMessage(lldb::tid_t tid, unsigned long *message);
219 
220   void NotifyThreadDeath(lldb::tid_t tid);
221 
222   Status Detach(lldb::tid_t tid);
223 
224   // This method is requests a stop on all threads which are still running. It
225   // sets up a
226   // deferred delegate notification, which will fire once threads report as
227   // stopped. The
228   // triggerring_tid will be set as the current thread (main stop reason).
229   void StopRunningThreads(lldb::tid_t triggering_tid);
230 
231   // Notify the delegate if all threads have stopped.
232   void SignalIfAllThreadsStopped();
233 
234   // Resume the given thread, optionally passing it the given signal. The type
235   // of resume
236   // operation (continue, single-step) depends on the state parameter.
237   Status ResumeThread(NativeThreadLinux &thread, lldb::StateType state,
238                       int signo);
239 
240   void ThreadWasCreated(NativeThreadLinux &thread);
241 
242   void SigchldHandler();
243 
244   Status PopulateMemoryRegionCache();
245 
246   lldb::user_id_t StartTraceGroup(const TraceOptions &config,
247                                          Status &error);
248 
249   // This function is intended to be used to stop tracing
250   // on a thread that exited.
251   Status StopTracingForThread(lldb::tid_t thread);
252 
253   // The below function as the name suggests, looks up a ProcessorTrace
254   // instance from the m_processor_trace_monitor map. In the case of
255   // process tracing where the traceid passed would map to the complete
256   // process, it is mandatory to provide a threadid to obtain a trace
257   // instance (since ProcessorTrace is tied to a thread). In the other
258   // scenario that an individual thread is being traced, just the traceid
259   // is sufficient to obtain the actual ProcessorTrace instance.
260   llvm::Expected<ProcessorTraceMonitor &>
261   LookupProcessorTraceInstance(lldb::user_id_t traceid, lldb::tid_t thread);
262 
263   // Stops tracing on individual threads being traced. Not intended
264   // to be used to stop tracing on complete process.
265   Status StopProcessorTracingOnThread(lldb::user_id_t traceid,
266                                       lldb::tid_t thread);
267 
268   // Intended to stop tracing on complete process.
269   // Should not be used for stopping trace on
270   // individual threads.
271   void StopProcessorTracingOnProcess();
272 
273   llvm::DenseMap<lldb::tid_t, ProcessorTraceMonitorUP>
274       m_processor_trace_monitor;
275 
276   // Set for tracking threads being traced under
277   // same process user id.
278   llvm::DenseSet<lldb::tid_t> m_pt_traced_thread_group;
279 
280   lldb::user_id_t m_pt_proces_trace_id = LLDB_INVALID_UID;
281   TraceOptions m_pt_process_trace_config;
282 };
283 
284 } // namespace process_linux
285 } // namespace lldb_private
286 
287 #endif // #ifndef liblldb_NativeProcessLinux_H_
288