1 //===-- ThreadGDBRemote.cpp -------------------------------------*- 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 
11 #include "ThreadGDBRemote.h"
12 
13 #include "lldb/Core/ArchSpec.h"
14 #include "lldb/Core/DataExtractor.h"
15 #include "lldb/Core/StreamString.h"
16 #include "lldb/Target/Process.h"
17 #include "lldb/Target/RegisterContext.h"
18 #include "lldb/Target/StopInfo.h"
19 #include "lldb/Target/Target.h"
20 #include "lldb/Target/Unwind.h"
21 #include "lldb/Breakpoint/WatchpointLocation.h"
22 
23 #include "LibUnwindRegisterContext.h"
24 #include "ProcessGDBRemote.h"
25 #include "ProcessGDBRemoteLog.h"
26 #include "Utility/StringExtractorGDBRemote.h"
27 #include "UnwindLibUnwind.h"
28 #include "UnwindMacOSXFrameBackchain.h"
29 
30 using namespace lldb;
31 using namespace lldb_private;
32 
33 //----------------------------------------------------------------------
34 // Thread Registers
35 //----------------------------------------------------------------------
36 
37 ThreadGDBRemote::ThreadGDBRemote (ProcessGDBRemote &process, lldb::tid_t tid) :
38     Thread(process, tid),
39     m_thread_name (),
40     m_dispatch_queue_name (),
41     m_thread_dispatch_qaddr (LLDB_INVALID_ADDRESS)
42 {
43 //    ProcessGDBRemoteLog::LogIf(GDBR_LOG_THREAD | GDBR_LOG_VERBOSE, "ThreadGDBRemote::ThreadGDBRemote ( pid = %i, tid = 0x%4.4x, )", m_process.GetID(), GetID());
44     ProcessGDBRemoteLog::LogIf(GDBR_LOG_THREAD, "%p: ThreadGDBRemote::ThreadGDBRemote (pid = %i, tid = 0x%4.4x)", this, m_process.GetID(), GetID());
45 }
46 
47 ThreadGDBRemote::~ThreadGDBRemote ()
48 {
49     ProcessGDBRemoteLog::LogIf(GDBR_LOG_THREAD, "%p: ThreadGDBRemote::~ThreadGDBRemote (pid = %i, tid = 0x%4.4x)", this, m_process.GetID(), GetID());
50 }
51 
52 
53 const char *
54 ThreadGDBRemote::GetInfo ()
55 {
56     return NULL;
57 }
58 
59 
60 const char *
61 ThreadGDBRemote::GetName ()
62 {
63     if (m_thread_name.empty())
64         return NULL;
65     return m_thread_name.c_str();
66 }
67 
68 
69 const char *
70 ThreadGDBRemote::GetQueueName ()
71 {
72     // Always re-fetch the dispatch queue name since it can change
73     if (m_thread_dispatch_qaddr != 0 || m_thread_dispatch_qaddr != LLDB_INVALID_ADDRESS)
74         return GetGDBProcess().GetDispatchQueueNameForThread (m_thread_dispatch_qaddr, m_dispatch_queue_name);
75     return NULL;
76 }
77 
78 bool
79 ThreadGDBRemote::WillResume (StateType resume_state)
80 {
81     ClearStackFrames();
82     // Call the Thread::WillResume first. If we stop at a signal, the stop info
83     // class for signal will set the resume signal that we need below. The signal
84     // stuff obeys the Process::UnixSignal defaults.
85     Thread::WillResume(resume_state);
86 
87     int signo = GetResumeSignal();
88 
89     switch (resume_state)
90     {
91     case eStateSuspended:
92     case eStateStopped:
93         // Don't append anything for threads that should stay stopped.
94         break;
95 
96     case eStateRunning:
97         if (m_process.GetUnixSignals().SignalIsValid (signo))
98             GetGDBProcess().m_continue_packet.Printf(";C%2.2x:%4.4x", signo, GetID());
99         else
100             GetGDBProcess().m_continue_packet.Printf(";c:%4.4x", GetID());
101         break;
102 
103     case eStateStepping:
104         if (m_process.GetUnixSignals().SignalIsValid (signo))
105             GetGDBProcess().m_continue_packet.Printf(";S%2.2x:%4.4x", signo, GetID());
106         else
107             GetGDBProcess().m_continue_packet.Printf(";s:%4.4x", GetID());
108         break;
109 
110     default:
111         break;
112     }
113     return true;
114 }
115 
116 void
117 ThreadGDBRemote::RefreshStateAfterStop()
118 {
119     // Invalidate all registers in our register context
120     GetRegisterContext()->Invalidate();
121 }
122 
123 Unwind *
124 ThreadGDBRemote::GetUnwinder ()
125 {
126     if (m_unwinder_ap.get() == NULL)
127     {
128         const ArchSpec target_arch (GetProcess().GetTarget().GetArchitecture ());
129         if (target_arch == ArchSpec("x86_64") ||  target_arch == ArchSpec("i386"))
130         {
131             m_unwinder_ap.reset (new UnwindLibUnwind (*this, GetGDBProcess().GetLibUnwindAddressSpace()));
132         }
133         else
134         {
135             m_unwinder_ap.reset (new UnwindMacOSXFrameBackchain (*this));
136         }
137     }
138     return m_unwinder_ap.get();
139 }
140 
141 void
142 ThreadGDBRemote::ClearStackFrames ()
143 {
144     Unwind *unwinder = GetUnwinder ();
145     if (unwinder)
146         unwinder->Clear();
147     Thread::ClearStackFrames();
148 }
149 
150 
151 bool
152 ThreadGDBRemote::ThreadIDIsValid (lldb::tid_t thread)
153 {
154     return thread != 0;
155 }
156 
157 void
158 ThreadGDBRemote::Dump(Log *log, uint32_t index)
159 {
160 }
161 
162 
163 bool
164 ThreadGDBRemote::ShouldStop (bool &step_more)
165 {
166     return true;
167 }
168 RegisterContext *
169 ThreadGDBRemote::GetRegisterContext ()
170 {
171     if (m_reg_context_sp.get() == NULL)
172         m_reg_context_sp.reset (CreateRegisterContextForFrame (NULL));
173     return m_reg_context_sp.get();
174 }
175 
176 RegisterContext *
177 ThreadGDBRemote::CreateRegisterContextForFrame (StackFrame *frame)
178 {
179     const bool read_all_registers_at_once = false;
180     uint32_t frame_idx = 0;
181 
182     if (frame)
183         frame_idx = frame->GetFrameIndex ();
184 
185     if (frame_idx == 0)
186         return new GDBRemoteRegisterContext (*this, frame, GetGDBProcess().m_register_info, read_all_registers_at_once);
187     else if (m_unwinder_ap.get())
188         return m_unwinder_ap->CreateRegisterContextForFrame (frame);
189     return NULL;
190 }
191 
192 bool
193 ThreadGDBRemote::SaveFrameZeroState (RegisterCheckpoint &checkpoint)
194 {
195     lldb::StackFrameSP frame_sp(GetStackFrameAtIndex (0));
196     if (frame_sp)
197     {
198         checkpoint.SetStackID(frame_sp->GetStackID());
199         return frame_sp->GetRegisterContext()->ReadAllRegisterValues (checkpoint.GetData());
200     }
201     return false;
202 }
203 
204 bool
205 ThreadGDBRemote::RestoreSaveFrameZero (const RegisterCheckpoint &checkpoint)
206 {
207     lldb::StackFrameSP frame_sp(GetStackFrameAtIndex (0));
208     if (frame_sp)
209     {
210         bool ret = frame_sp->GetRegisterContext()->WriteAllRegisterValues (checkpoint.GetData());
211         frame_sp->GetRegisterContext()->Invalidate();
212         ClearStackFrames();
213         return ret;
214     }
215     return false;
216 }
217 
218 lldb::StopInfoSP
219 ThreadGDBRemote::GetPrivateStopReason ()
220 {
221     if (m_actual_stop_info_sp.get() == NULL || m_actual_stop_info_sp->IsValid() == false)
222     {
223         m_actual_stop_info_sp.reset();
224 
225         char packet[256];
226         ::snprintf(packet, sizeof(packet), "qThreadStopInfo%x", GetID());
227         StringExtractorGDBRemote stop_packet;
228         if (GetGDBProcess().GetGDBRemote().SendPacketAndWaitForResponse(packet, stop_packet, 1, false))
229         {
230             std::string copy(stop_packet.GetStringRef());
231             GetGDBProcess().SetThreadStopInfo (stop_packet);
232         }
233     }
234     return m_actual_stop_info_sp;
235 }
236 
237 
238