1 //===-- StopInfo.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 LLDB_TARGET_STOPINFO_H 10 #define LLDB_TARGET_STOPINFO_H 11 12 #include <string> 13 14 #include "lldb/Target/Process.h" 15 #include "lldb/Utility/StructuredData.h" 16 #include "lldb/lldb-public.h" 17 18 namespace lldb_private { 19 20 class StopInfo { 21 friend class Process::ProcessEventData; 22 friend class ThreadPlanBase; 23 24 public: 25 // Constructors and Destructors 26 StopInfo(Thread &thread, uint64_t value); 27 ~StopInfo()28 virtual ~StopInfo() {} 29 30 bool IsValid() const; 31 SetThread(const lldb::ThreadSP & thread_sp)32 void SetThread(const lldb::ThreadSP &thread_sp) { m_thread_wp = thread_sp; } 33 GetThread()34 lldb::ThreadSP GetThread() const { return m_thread_wp.lock(); } 35 36 // The value of the StopInfo depends on the StopReason. 37 // 38 // StopReason Meaning 39 // ------------------------------------------------ 40 // eStopReasonBreakpoint BreakpointSiteID 41 // eStopReasonSignal Signal number 42 // eStopReasonWatchpoint WatchpointLocationID 43 // eStopReasonPlanComplete No significance 44 GetValue()45 uint64_t GetValue() const { return m_value; } 46 47 virtual lldb::StopReason GetStopReason() const = 0; 48 49 // ShouldStopSynchronous will get called before any thread plans are 50 // consulted, and if it says we should resume the target, then we will just 51 // immediately resume. This should not run any code in or resume the target. 52 ShouldStopSynchronous(Event * event_ptr)53 virtual bool ShouldStopSynchronous(Event *event_ptr) { return true; } 54 OverrideShouldNotify(bool override_value)55 void OverrideShouldNotify(bool override_value) { 56 m_override_should_notify = override_value ? eLazyBoolYes : eLazyBoolNo; 57 } 58 59 // If should stop returns false, check if we should notify of this event ShouldNotify(Event * event_ptr)60 virtual bool ShouldNotify(Event *event_ptr) { 61 if (m_override_should_notify == eLazyBoolCalculate) 62 return DoShouldNotify(event_ptr); 63 else 64 return m_override_should_notify == eLazyBoolYes; 65 } 66 WillResume(lldb::StateType resume_state)67 virtual void WillResume(lldb::StateType resume_state) { 68 // By default, don't do anything 69 } 70 GetDescription()71 virtual const char *GetDescription() { return m_description.c_str(); } 72 SetDescription(const char * desc_cstr)73 virtual void SetDescription(const char *desc_cstr) { 74 if (desc_cstr && desc_cstr[0]) 75 m_description.assign(desc_cstr); 76 else 77 m_description.clear(); 78 } 79 IsValidForOperatingSystemThread(Thread & thread)80 virtual bool IsValidForOperatingSystemThread(Thread &thread) { return true; } 81 82 // Sometimes the thread plan logic will know that it wants a given stop to 83 // stop or not, regardless of what the ordinary logic for that StopInfo would 84 // dictate. The main example of this is the ThreadPlanCallFunction, which 85 // for instance knows - based on how that particular expression was executed 86 // - whether it wants all breakpoints to auto-continue or not. Use 87 // OverrideShouldStop on the StopInfo to implement this. 88 OverrideShouldStop(bool override_value)89 void OverrideShouldStop(bool override_value) { 90 m_override_should_stop = override_value ? eLazyBoolYes : eLazyBoolNo; 91 } 92 GetOverrideShouldStop()93 bool GetOverrideShouldStop() { 94 return m_override_should_stop != eLazyBoolCalculate; 95 } 96 GetOverriddenShouldStopValue()97 bool GetOverriddenShouldStopValue() { 98 return m_override_should_stop == eLazyBoolYes; 99 } 100 GetExtendedInfo()101 StructuredData::ObjectSP GetExtendedInfo() { return m_extended_info; } 102 103 static lldb::StopInfoSP 104 CreateStopReasonWithBreakpointSiteID(Thread &thread, 105 lldb::break_id_t break_id); 106 107 // This creates a StopInfo for the thread where the should_stop is already 108 // set, and won't be recalculated. 109 static lldb::StopInfoSP CreateStopReasonWithBreakpointSiteID( 110 Thread &thread, lldb::break_id_t break_id, bool should_stop); 111 112 static lldb::StopInfoSP CreateStopReasonWithWatchpointID( 113 Thread &thread, lldb::break_id_t watch_id, 114 lldb::addr_t watch_hit_addr = LLDB_INVALID_ADDRESS); 115 116 static lldb::StopInfoSP 117 CreateStopReasonWithSignal(Thread &thread, int signo, 118 const char *description = nullptr); 119 120 static lldb::StopInfoSP CreateStopReasonToTrace(Thread &thread); 121 122 static lldb::StopInfoSP 123 CreateStopReasonWithPlan(lldb::ThreadPlanSP &plan, 124 lldb::ValueObjectSP return_valobj_sp, 125 lldb::ExpressionVariableSP expression_variable_sp); 126 127 static lldb::StopInfoSP 128 CreateStopReasonWithException(Thread &thread, const char *description); 129 130 static lldb::StopInfoSP CreateStopReasonWithExec(Thread &thread); 131 132 static lldb::ValueObjectSP 133 GetReturnValueObject(lldb::StopInfoSP &stop_info_sp); 134 135 static lldb::ExpressionVariableSP 136 GetExpressionVariable(lldb::StopInfoSP &stop_info_sp); 137 138 static lldb::ValueObjectSP 139 GetCrashingDereference(lldb::StopInfoSP &stop_info_sp, 140 lldb::addr_t *crashing_address = nullptr); 141 142 protected: 143 // Perform any action that is associated with this stop. This is done as the 144 // Event is removed from the event queue. ProcessEventData::DoOnRemoval does 145 // the job. 146 PerformAction(Event * event_ptr)147 virtual void PerformAction(Event *event_ptr) {} 148 DoShouldNotify(Event * event_ptr)149 virtual bool DoShouldNotify(Event *event_ptr) { return false; } 150 151 // Stop the thread by default. Subclasses can override this to allow the 152 // thread to continue if desired. The ShouldStop method should not do 153 // anything that might run code. If you need to run code when deciding 154 // whether to stop at this StopInfo, that must be done in the PerformAction. 155 // The PerformAction will always get called before the ShouldStop. This is 156 // done by the ProcessEventData::DoOnRemoval, though the ThreadPlanBase needs 157 // to consult this later on. ShouldStop(Event * event_ptr)158 virtual bool ShouldStop(Event *event_ptr) { return true; } 159 160 // Classes that inherit from StackID can see and modify these 161 lldb::ThreadWP m_thread_wp; // The thread corresponding to the stop reason. 162 uint32_t m_stop_id; // The process stop ID for which this stop info is valid 163 uint32_t m_resume_id; // This is the resume ID when we made this stop ID. 164 uint64_t m_value; // A generic value that can be used for things pertaining to 165 // this stop info 166 std::string m_description; // A textual description describing this stop. 167 LazyBool m_override_should_notify; 168 LazyBool m_override_should_stop; 169 170 StructuredData::ObjectSP 171 m_extended_info; // The extended info for this stop info 172 173 // This determines whether the target has run since this stop info. N.B. 174 // running to evaluate a user expression does not count. 175 bool HasTargetRunSinceMe(); 176 177 // MakeStopInfoValid is necessary to allow saved stop infos to resurrect 178 // themselves as valid. It should only be used by 179 // Thread::RestoreThreadStateFromCheckpoint and to make sure the one-step 180 // needed for before-the-fact watchpoints does not prevent us from stopping 181 void MakeStopInfoValid(); 182 183 private: 184 friend class Thread; 185 186 StopInfo(const StopInfo &) = delete; 187 const StopInfo &operator=(const StopInfo &) = delete; 188 }; 189 190 } // namespace lldb_private 191 192 #endif // LLDB_TARGET_STOPINFO_H 193