1 //===-- NativeProcessLinux.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 //===----------------------------------------------------------------------===//
8 
9 #ifndef liblldb_NativeProcessLinux_H_
10 #define liblldb_NativeProcessLinux_H_
11 
12 #include <csignal>
13 #include <unordered_set>
14 
15 #include "Plugins/Process/Utility/AuxVector.h"
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   // NativeProcessProtocol Interface
54   Status Resume(const ResumeActionList &resume_actions) override;
55 
56   Status Halt() override;
57 
58   Status Detach() override;
59 
60   Status Signal(int signo) override;
61 
62   Status Interrupt() override;
63 
64   Status Kill() override;
65 
66   Status GetMemoryRegionInfo(lldb::addr_t load_addr,
67                              MemoryRegionInfo &range_info) override;
68 
69   Status ReadMemory(lldb::addr_t addr, void *buf, size_t size,
70                     size_t &bytes_read) override;
71 
72   Status WriteMemory(lldb::addr_t addr, const void *buf, size_t size,
73                      size_t &bytes_written) override;
74 
75   Status AllocateMemory(size_t size, uint32_t permissions,
76                         lldb::addr_t &addr) override;
77 
78   Status DeallocateMemory(lldb::addr_t addr) override;
79 
80   lldb::addr_t GetSharedLibraryInfoAddress() override;
81 
82   size_t UpdateThreads() override;
83 
84   const ArchSpec &GetArchitecture() const override { return m_arch; }
85 
86   Status SetBreakpoint(lldb::addr_t addr, uint32_t size,
87                        bool hardware) override;
88 
89   Status RemoveBreakpoint(lldb::addr_t addr, bool hardware = false) override;
90 
91   void DoStopIDBumped(uint32_t newBumpId) override;
92 
93   Status GetLoadedModuleFileSpec(const char *module_path,
94                                  FileSpec &file_spec) override;
95 
96   Status GetFileLoadAddress(const llvm::StringRef &file_name,
97                             lldb::addr_t &load_addr) override;
98 
99   NativeThreadLinux *GetThreadByID(lldb::tid_t id);
100 
101   llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
102   GetAuxvData() const override {
103     return getProcFile(GetID(), "auxv");
104   }
105 
106   llvm::Optional<uint64_t> GetAuxValue(enum AuxVector::EntryType type);
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   // Interface used by NativeRegisterContext-derived classes.
125   static Status PtraceWrapper(int req, lldb::pid_t pid, void *addr = nullptr,
126                               void *data = nullptr, size_t data_size = 0,
127                               long *result = nullptr);
128 
129   bool SupportHardwareSingleStepping() const;
130 
131 protected:
132   llvm::Expected<llvm::ArrayRef<uint8_t>>
133   GetSoftwareBreakpointTrapOpcode(size_t size_hint) override;
134 
135 private:
136   MainLoop::SignalHandleUP m_sigchld_handle;
137   ArchSpec m_arch;
138   std::unique_ptr<AuxVector> m_aux_vector;
139 
140   LazyBool m_supports_mem_region = eLazyBoolCalculate;
141   std::vector<std::pair<MemoryRegionInfo, FileSpec>> m_mem_region_cache;
142 
143   lldb::tid_t m_pending_notification_tid = LLDB_INVALID_THREAD_ID;
144 
145   // List of thread ids stepping with a breakpoint with the address of
146   // the relevan breakpoint
147   std::map<lldb::tid_t, lldb::addr_t> m_threads_stepping_with_breakpoint;
148 
149   // Private Instance Methods
150   NativeProcessLinux(::pid_t pid, int terminal_fd, NativeDelegate &delegate,
151                      const ArchSpec &arch, MainLoop &mainloop,
152                      llvm::ArrayRef<::pid_t> tids);
153 
154   // Returns a list of process threads that we have attached to.
155   static llvm::Expected<std::vector<::pid_t>> Attach(::pid_t pid);
156 
157   static Status SetDefaultPtraceOpts(const lldb::pid_t);
158 
159   void MonitorCallback(lldb::pid_t pid, bool exited, WaitStatus status);
160 
161   void WaitForNewThread(::pid_t tid);
162 
163   void MonitorSIGTRAP(const siginfo_t &info, NativeThreadLinux &thread);
164 
165   void MonitorTrace(NativeThreadLinux &thread);
166 
167   void MonitorBreakpoint(NativeThreadLinux &thread);
168 
169   void MonitorWatchpoint(NativeThreadLinux &thread, uint32_t wp_index);
170 
171   void MonitorSignal(const siginfo_t &info, NativeThreadLinux &thread,
172                      bool exited);
173 
174   Status SetupSoftwareSingleStepping(NativeThreadLinux &thread);
175 
176   bool HasThreadNoLock(lldb::tid_t thread_id);
177 
178   bool StopTrackingThread(lldb::tid_t thread_id);
179 
180   NativeThreadLinux &AddThread(lldb::tid_t thread_id);
181 
182   /// Writes a siginfo_t structure corresponding to the given thread ID to the
183   /// memory region pointed to by \p siginfo.
184   Status GetSignalInfo(lldb::tid_t tid, void *siginfo);
185 
186   /// Writes the raw event message code (vis-a-vis PTRACE_GETEVENTMSG)
187   /// corresponding to the given thread ID to the memory pointed to by @p
188   /// message.
189   Status GetEventMessage(lldb::tid_t tid, unsigned long *message);
190 
191   void NotifyThreadDeath(lldb::tid_t tid);
192 
193   Status Detach(lldb::tid_t tid);
194 
195   // This method is requests a stop on all threads which are still running. It
196   // sets up a
197   // deferred delegate notification, which will fire once threads report as
198   // stopped. The
199   // triggerring_tid will be set as the current thread (main stop reason).
200   void StopRunningThreads(lldb::tid_t triggering_tid);
201 
202   // Notify the delegate if all threads have stopped.
203   void SignalIfAllThreadsStopped();
204 
205   // Resume the given thread, optionally passing it the given signal. The type
206   // of resume
207   // operation (continue, single-step) depends on the state parameter.
208   Status ResumeThread(NativeThreadLinux &thread, lldb::StateType state,
209                       int signo);
210 
211   void ThreadWasCreated(NativeThreadLinux &thread);
212 
213   void SigchldHandler();
214 
215   Status PopulateMemoryRegionCache();
216 
217   lldb::user_id_t StartTraceGroup(const TraceOptions &config,
218                                          Status &error);
219 
220   // This function is intended to be used to stop tracing
221   // on a thread that exited.
222   Status StopTracingForThread(lldb::tid_t thread);
223 
224   // The below function as the name suggests, looks up a ProcessorTrace
225   // instance from the m_processor_trace_monitor map. In the case of
226   // process tracing where the traceid passed would map to the complete
227   // process, it is mandatory to provide a threadid to obtain a trace
228   // instance (since ProcessorTrace is tied to a thread). In the other
229   // scenario that an individual thread is being traced, just the traceid
230   // is sufficient to obtain the actual ProcessorTrace instance.
231   llvm::Expected<ProcessorTraceMonitor &>
232   LookupProcessorTraceInstance(lldb::user_id_t traceid, lldb::tid_t thread);
233 
234   // Stops tracing on individual threads being traced. Not intended
235   // to be used to stop tracing on complete process.
236   Status StopProcessorTracingOnThread(lldb::user_id_t traceid,
237                                       lldb::tid_t thread);
238 
239   // Intended to stop tracing on complete process.
240   // Should not be used for stopping trace on
241   // individual threads.
242   void StopProcessorTracingOnProcess();
243 
244   llvm::DenseMap<lldb::tid_t, ProcessorTraceMonitorUP>
245       m_processor_trace_monitor;
246 
247   // Set for tracking threads being traced under
248   // same process user id.
249   llvm::DenseSet<lldb::tid_t> m_pt_traced_thread_group;
250 
251   lldb::user_id_t m_pt_proces_trace_id = LLDB_INVALID_UID;
252   TraceOptions m_pt_process_trace_config;
253 };
254 
255 } // namespace process_linux
256 } // namespace lldb_private
257 
258 #endif // #ifndef liblldb_NativeProcessLinux_H_
259