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