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   llvm::Expected<llvm::ArrayRef<uint8_t>>
138   GetSoftwareBreakpointTrapOpcode(size_t size_hint) override;
139 
140 private:
141   MainLoop::SignalHandleUP m_sigchld_handle;
142   ArchSpec m_arch;
143 
144   LazyBool m_supports_mem_region = eLazyBoolCalculate;
145   std::vector<std::pair<MemoryRegionInfo, FileSpec>> m_mem_region_cache;
146 
147   lldb::tid_t m_pending_notification_tid = LLDB_INVALID_THREAD_ID;
148 
149   // List of thread ids stepping with a breakpoint with the address of
150   // the relevan breakpoint
151   std::map<lldb::tid_t, lldb::addr_t> m_threads_stepping_with_breakpoint;
152 
153   // ---------------------------------------------------------------------
154   // Private Instance Methods
155   // ---------------------------------------------------------------------
156   NativeProcessLinux(::pid_t pid, int terminal_fd, NativeDelegate &delegate,
157                      const ArchSpec &arch, MainLoop &mainloop,
158                      llvm::ArrayRef<::pid_t> tids);
159 
160   // Returns a list of process threads that we have attached to.
161   static llvm::Expected<std::vector<::pid_t>> Attach(::pid_t pid);
162 
163   static Status SetDefaultPtraceOpts(const lldb::pid_t);
164 
165   void MonitorCallback(lldb::pid_t pid, bool exited, WaitStatus status);
166 
167   void WaitForNewThread(::pid_t tid);
168 
169   void MonitorSIGTRAP(const siginfo_t &info, NativeThreadLinux &thread);
170 
171   void MonitorTrace(NativeThreadLinux &thread);
172 
173   void MonitorBreakpoint(NativeThreadLinux &thread);
174 
175   void MonitorWatchpoint(NativeThreadLinux &thread, uint32_t wp_index);
176 
177   void MonitorSignal(const siginfo_t &info, NativeThreadLinux &thread,
178                      bool exited);
179 
180   Status SetupSoftwareSingleStepping(NativeThreadLinux &thread);
181 
182   bool HasThreadNoLock(lldb::tid_t thread_id);
183 
184   bool StopTrackingThread(lldb::tid_t thread_id);
185 
186   NativeThreadLinux &AddThread(lldb::tid_t thread_id);
187 
188   Status GetSoftwareBreakpointPCOffset(uint32_t &actual_opcode_size);
189 
190   Status FixupBreakpointPCAsNeeded(NativeThreadLinux &thread);
191 
192   /// Writes a siginfo_t structure corresponding to the given thread ID to the
193   /// memory region pointed to by @p siginfo.
194   Status GetSignalInfo(lldb::tid_t tid, void *siginfo);
195 
196   /// Writes the raw event message code (vis-a-vis PTRACE_GETEVENTMSG)
197   /// corresponding to the given thread ID to the memory pointed to by @p
198   /// message.
199   Status GetEventMessage(lldb::tid_t tid, unsigned long *message);
200 
201   void NotifyThreadDeath(lldb::tid_t tid);
202 
203   Status Detach(lldb::tid_t tid);
204 
205   // This method is requests a stop on all threads which are still running. It
206   // sets up a
207   // deferred delegate notification, which will fire once threads report as
208   // stopped. The
209   // triggerring_tid will be set as the current thread (main stop reason).
210   void StopRunningThreads(lldb::tid_t triggering_tid);
211 
212   // Notify the delegate if all threads have stopped.
213   void SignalIfAllThreadsStopped();
214 
215   // Resume the given thread, optionally passing it the given signal. The type
216   // of resume
217   // operation (continue, single-step) depends on the state parameter.
218   Status ResumeThread(NativeThreadLinux &thread, lldb::StateType state,
219                       int signo);
220 
221   void ThreadWasCreated(NativeThreadLinux &thread);
222 
223   void SigchldHandler();
224 
225   Status PopulateMemoryRegionCache();
226 
227   lldb::user_id_t StartTraceGroup(const TraceOptions &config,
228                                          Status &error);
229 
230   // This function is intended to be used to stop tracing
231   // on a thread that exited.
232   Status StopTracingForThread(lldb::tid_t thread);
233 
234   // The below function as the name suggests, looks up a ProcessorTrace
235   // instance from the m_processor_trace_monitor map. In the case of
236   // process tracing where the traceid passed would map to the complete
237   // process, it is mandatory to provide a threadid to obtain a trace
238   // instance (since ProcessorTrace is tied to a thread). In the other
239   // scenario that an individual thread is being traced, just the traceid
240   // is sufficient to obtain the actual ProcessorTrace instance.
241   llvm::Expected<ProcessorTraceMonitor &>
242   LookupProcessorTraceInstance(lldb::user_id_t traceid, lldb::tid_t thread);
243 
244   // Stops tracing on individual threads being traced. Not intended
245   // to be used to stop tracing on complete process.
246   Status StopProcessorTracingOnThread(lldb::user_id_t traceid,
247                                       lldb::tid_t thread);
248 
249   // Intended to stop tracing on complete process.
250   // Should not be used for stopping trace on
251   // individual threads.
252   void StopProcessorTracingOnProcess();
253 
254   llvm::DenseMap<lldb::tid_t, ProcessorTraceMonitorUP>
255       m_processor_trace_monitor;
256 
257   // Set for tracking threads being traced under
258   // same process user id.
259   llvm::DenseSet<lldb::tid_t> m_pt_traced_thread_group;
260 
261   lldb::user_id_t m_pt_proces_trace_id = LLDB_INVALID_UID;
262   TraceOptions m_pt_process_trace_config;
263 };
264 
265 } // namespace process_linux
266 } // namespace lldb_private
267 
268 #endif // #ifndef liblldb_NativeProcessLinux_H_
269