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 WriteMemory(lldb::addr_t addr, const void *buf, size_t size,
75                      size_t &bytes_written) override;
76 
77   Status AllocateMemory(size_t size, uint32_t permissions,
78                         lldb::addr_t &addr) override;
79 
80   Status DeallocateMemory(lldb::addr_t addr) override;
81 
82   lldb::addr_t GetSharedLibraryInfoAddress() override;
83 
84   size_t UpdateThreads() override;
85 
86   const ArchSpec &GetArchitecture() const override { return m_arch; }
87 
88   Status SetBreakpoint(lldb::addr_t addr, uint32_t size,
89                        bool hardware) override;
90 
91   Status RemoveBreakpoint(lldb::addr_t addr, bool hardware = false) override;
92 
93   void DoStopIDBumped(uint32_t newBumpId) override;
94 
95   Status GetLoadedModuleFileSpec(const char *module_path,
96                                  FileSpec &file_spec) override;
97 
98   Status GetFileLoadAddress(const llvm::StringRef &file_name,
99                             lldb::addr_t &load_addr) override;
100 
101   NativeThreadLinux *GetThreadByID(lldb::tid_t id);
102 
103   llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
104   GetAuxvData() const override {
105     return getProcFile(GetID(), "auxv");
106   }
107 
108   lldb::user_id_t StartTrace(const TraceOptions &config,
109                              Status &error) override;
110 
111   Status StopTrace(lldb::user_id_t traceid,
112                    lldb::tid_t thread) override;
113 
114   Status GetData(lldb::user_id_t traceid, lldb::tid_t thread,
115                  llvm::MutableArrayRef<uint8_t> &buffer,
116                  size_t offset = 0) override;
117 
118   Status GetMetaData(lldb::user_id_t traceid, lldb::tid_t thread,
119                      llvm::MutableArrayRef<uint8_t> &buffer,
120                      size_t offset = 0) override;
121 
122   Status GetTraceConfig(lldb::user_id_t traceid, TraceOptions &config) override;
123 
124   // ---------------------------------------------------------------------
125   // Interface used by NativeRegisterContext-derived classes.
126   // ---------------------------------------------------------------------
127   static Status PtraceWrapper(int req, lldb::pid_t pid, void *addr = nullptr,
128                               void *data = nullptr, size_t data_size = 0,
129                               long *result = nullptr);
130 
131   bool SupportHardwareSingleStepping() const;
132 
133 protected:
134   llvm::Expected<llvm::ArrayRef<uint8_t>>
135   GetSoftwareBreakpointTrapOpcode(size_t size_hint) override;
136 
137 private:
138   MainLoop::SignalHandleUP m_sigchld_handle;
139   ArchSpec m_arch;
140 
141   LazyBool m_supports_mem_region = eLazyBoolCalculate;
142   std::vector<std::pair<MemoryRegionInfo, FileSpec>> m_mem_region_cache;
143 
144   lldb::tid_t m_pending_notification_tid = LLDB_INVALID_THREAD_ID;
145 
146   // List of thread ids stepping with a breakpoint with the address of
147   // the relevan breakpoint
148   std::map<lldb::tid_t, lldb::addr_t> m_threads_stepping_with_breakpoint;
149 
150   // ---------------------------------------------------------------------
151   // Private Instance Methods
152   // ---------------------------------------------------------------------
153   NativeProcessLinux(::pid_t pid, int terminal_fd, NativeDelegate &delegate,
154                      const ArchSpec &arch, MainLoop &mainloop,
155                      llvm::ArrayRef<::pid_t> tids);
156 
157   // Returns a list of process threads that we have attached to.
158   static llvm::Expected<std::vector<::pid_t>> Attach(::pid_t pid);
159 
160   static Status SetDefaultPtraceOpts(const lldb::pid_t);
161 
162   void MonitorCallback(lldb::pid_t pid, bool exited, WaitStatus status);
163 
164   void WaitForNewThread(::pid_t tid);
165 
166   void MonitorSIGTRAP(const siginfo_t &info, NativeThreadLinux &thread);
167 
168   void MonitorTrace(NativeThreadLinux &thread);
169 
170   void MonitorBreakpoint(NativeThreadLinux &thread);
171 
172   void MonitorWatchpoint(NativeThreadLinux &thread, uint32_t wp_index);
173 
174   void MonitorSignal(const siginfo_t &info, NativeThreadLinux &thread,
175                      bool exited);
176 
177   Status SetupSoftwareSingleStepping(NativeThreadLinux &thread);
178 
179   bool HasThreadNoLock(lldb::tid_t thread_id);
180 
181   bool StopTrackingThread(lldb::tid_t thread_id);
182 
183   NativeThreadLinux &AddThread(lldb::tid_t thread_id);
184 
185   /// Writes a siginfo_t structure corresponding to the given thread ID to the
186   /// memory region pointed to by @p siginfo.
187   Status GetSignalInfo(lldb::tid_t tid, void *siginfo);
188 
189   /// Writes the raw event message code (vis-a-vis PTRACE_GETEVENTMSG)
190   /// corresponding to the given thread ID to the memory pointed to by @p
191   /// message.
192   Status GetEventMessage(lldb::tid_t tid, unsigned long *message);
193 
194   void NotifyThreadDeath(lldb::tid_t tid);
195 
196   Status Detach(lldb::tid_t tid);
197 
198   // This method is requests a stop on all threads which are still running. It
199   // sets up a
200   // deferred delegate notification, which will fire once threads report as
201   // stopped. The
202   // triggerring_tid will be set as the current thread (main stop reason).
203   void StopRunningThreads(lldb::tid_t triggering_tid);
204 
205   // Notify the delegate if all threads have stopped.
206   void SignalIfAllThreadsStopped();
207 
208   // Resume the given thread, optionally passing it the given signal. The type
209   // of resume
210   // operation (continue, single-step) depends on the state parameter.
211   Status ResumeThread(NativeThreadLinux &thread, lldb::StateType state,
212                       int signo);
213 
214   void ThreadWasCreated(NativeThreadLinux &thread);
215 
216   void SigchldHandler();
217 
218   Status PopulateMemoryRegionCache();
219 
220   lldb::user_id_t StartTraceGroup(const TraceOptions &config,
221                                          Status &error);
222 
223   // This function is intended to be used to stop tracing
224   // on a thread that exited.
225   Status StopTracingForThread(lldb::tid_t thread);
226 
227   // The below function as the name suggests, looks up a ProcessorTrace
228   // instance from the m_processor_trace_monitor map. In the case of
229   // process tracing where the traceid passed would map to the complete
230   // process, it is mandatory to provide a threadid to obtain a trace
231   // instance (since ProcessorTrace is tied to a thread). In the other
232   // scenario that an individual thread is being traced, just the traceid
233   // is sufficient to obtain the actual ProcessorTrace instance.
234   llvm::Expected<ProcessorTraceMonitor &>
235   LookupProcessorTraceInstance(lldb::user_id_t traceid, lldb::tid_t thread);
236 
237   // Stops tracing on individual threads being traced. Not intended
238   // to be used to stop tracing on complete process.
239   Status StopProcessorTracingOnThread(lldb::user_id_t traceid,
240                                       lldb::tid_t thread);
241 
242   // Intended to stop tracing on complete process.
243   // Should not be used for stopping trace on
244   // individual threads.
245   void StopProcessorTracingOnProcess();
246 
247   llvm::DenseMap<lldb::tid_t, ProcessorTraceMonitorUP>
248       m_processor_trace_monitor;
249 
250   // Set for tracking threads being traced under
251   // same process user id.
252   llvm::DenseSet<lldb::tid_t> m_pt_traced_thread_group;
253 
254   lldb::user_id_t m_pt_proces_trace_id = LLDB_INVALID_UID;
255   TraceOptions m_pt_process_trace_config;
256 };
257 
258 } // namespace process_linux
259 } // namespace lldb_private
260 
261 #endif // #ifndef liblldb_NativeProcessLinux_H_
262