xref: /llvm-project/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.cpp (revision 82305fc59a70f3b10b07235daa2601d08aebf0d3)
1 //===-- GDBRemoteCommunication.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 "GDBRemoteCommunication.h"
12 
13 // C Includes
14 // C++ Includes
15 // Other libraries and framework includes
16 #include "lldb/Interpreter/Args.h"
17 #include "lldb/Core/ConnectionFileDescriptor.h"
18 #include "lldb/Core/Log.h"
19 #include "lldb/Core/State.h"
20 #include "lldb/Core/StreamString.h"
21 #include "lldb/Host/TimeValue.h"
22 
23 // Project includes
24 #include "Utility/StringExtractorGDBRemote.h"
25 #include "ProcessGDBRemote.h"
26 #include "ProcessGDBRemoteLog.h"
27 
28 using namespace lldb;
29 using namespace lldb_private;
30 
31 //----------------------------------------------------------------------
32 // GDBRemoteCommunication constructor
33 //----------------------------------------------------------------------
34 GDBRemoteCommunication::GDBRemoteCommunication() :
35     Communication("gdb-remote.packets", true),
36     m_send_acks (true),
37     m_rx_packet_listener ("gdbremote.rx_packet"),
38     m_sequence_mutex (Mutex::eMutexTypeRecursive),
39     m_is_running (false),
40     m_async_mutex (Mutex::eMutexTypeRecursive),
41     m_async_packet_predicate (false),
42     m_async_packet (),
43     m_async_response (),
44     m_async_timeout (UINT32_MAX),
45     m_async_signal (-1),
46     m_arch(),
47     m_os(),
48     m_vendor(),
49     m_byte_order(eByteOrderHost),
50     m_pointer_byte_size(0)
51 {
52     m_rx_packet_listener.StartListeningForEvents(this,
53                                                  Communication::eBroadcastBitPacketAvailable  |
54                                                  Communication::eBroadcastBitReadThreadDidExit);
55 }
56 
57 //----------------------------------------------------------------------
58 // Destructor
59 //----------------------------------------------------------------------
60 GDBRemoteCommunication::~GDBRemoteCommunication()
61 {
62     m_rx_packet_listener.StopListeningForEvents(this,
63                                                 Communication::eBroadcastBitPacketAvailable  |
64                                                 Communication::eBroadcastBitReadThreadDidExit);
65     if (IsConnected())
66     {
67         StopReadThread();
68         Disconnect();
69     }
70 }
71 
72 
73 char
74 GDBRemoteCommunication::CalculcateChecksum (const char *payload, size_t payload_length)
75 {
76     int checksum = 0;
77 
78     // We only need to compute the checksum if we are sending acks
79     if (m_send_acks)
80     {
81         for (size_t i = 0; i < payload_length; ++i)
82             checksum += payload[i];
83     }
84     return checksum & 255;
85 }
86 
87 size_t
88 GDBRemoteCommunication::SendAck (char ack_char)
89 {
90     Mutex::Locker locker(m_sequence_mutex);
91     ProcessGDBRemoteLog::LogIf (GDBR_LOG_PACKETS, "send packet: %c", ack_char);
92     ConnectionStatus status = eConnectionStatusSuccess;
93     return Write (&ack_char, 1, status, NULL) == 1;
94 }
95 
96 size_t
97 GDBRemoteCommunication::SendPacketAndWaitForResponse
98 (
99     const char *payload,
100     StringExtractorGDBRemote &response,
101     uint32_t timeout_seconds,
102     bool send_async
103 )
104 {
105     return SendPacketAndWaitForResponse (payload,
106                                          ::strlen (payload),
107                                          response,
108                                          timeout_seconds,
109                                          send_async);
110 }
111 
112 size_t
113 GDBRemoteCommunication::SendPacketAndWaitForResponse
114 (
115     const char *payload,
116     size_t payload_length,
117     StringExtractorGDBRemote &response,
118     uint32_t timeout_seconds,
119     bool send_async
120 )
121 {
122     Mutex::Locker locker;
123     TimeValue timeout_time;
124     timeout_time = TimeValue::Now();
125     timeout_time.OffsetWithSeconds (timeout_seconds);
126 
127     if (GetSequenceMutex (locker))
128     {
129         if (SendPacketNoLock (payload, strlen(payload)))
130             return WaitForPacketNoLock (response, &timeout_time);
131     }
132     else
133     {
134         if (send_async)
135         {
136             Mutex::Locker async_locker (m_async_mutex);
137             m_async_packet.assign(payload, payload_length);
138             m_async_timeout = timeout_seconds;
139             m_async_packet_predicate.SetValue (true, eBroadcastNever);
140 
141             bool timed_out = false;
142             if (SendInterrupt(locker, 1, &timed_out))
143             {
144                 if (m_async_packet_predicate.WaitForValueEqualTo (false, &timeout_time, &timed_out))
145                 {
146                     response = m_async_response;
147                     return response.GetStringRef().size();
148                 }
149             }
150 //            if (timed_out)
151 //                m_error.SetErrorString("Timeout.");
152 //            else
153 //                m_error.SetErrorString("Unknown error.");
154         }
155         else
156         {
157 //            m_error.SetErrorString("Sequence mutex is locked.");
158         }
159     }
160     return 0;
161 }
162 
163 //template<typename _Tp>
164 //class ScopedValueChanger
165 //{
166 //public:
167 //    // Take a value reference and the value to assing it to when this class
168 //    // instance goes out of scope.
169 //    ScopedValueChanger (_Tp &value_ref, _Tp value) :
170 //        m_value_ref (value_ref),
171 //        m_value (value)
172 //    {
173 //    }
174 //
175 //    // This object is going out of scope, change the value pointed to by
176 //    // m_value_ref to the value we got during construction which was stored in
177 //    // m_value;
178 //    ~ScopedValueChanger ()
179 //    {
180 //        m_value_ref = m_value;
181 //    }
182 //protected:
183 //    _Tp &m_value_ref;   // A reference to the value we wil change when this object destructs
184 //    _Tp m_value;        // The value to assign to m_value_ref when this goes out of scope.
185 //};
186 
187 StateType
188 GDBRemoteCommunication::SendContinuePacketAndWaitForResponse
189 (
190     ProcessGDBRemote *process,
191     const char *payload,
192     size_t packet_length,
193     StringExtractorGDBRemote &response
194 )
195 {
196     LogSP log (ProcessGDBRemoteLog::GetLogIfAllCategoriesSet (GDBR_LOG_PROCESS));
197     LogSP async_log(ProcessGDBRemoteLog::GetLogIfAllCategoriesSet (GDBR_LOG_ASYNC));
198     if (log)
199         log->Printf ("GDBRemoteCommunication::%s ()", __FUNCTION__);
200 
201     Mutex::Locker locker(m_sequence_mutex);
202 //    ScopedValueChanger<bool> restore_running_to_false (m_is_running, false);
203     StateType state = eStateRunning;
204 
205     if (SendPacket(payload, packet_length) == 0)
206         state = eStateInvalid;
207 
208     m_is_running.SetValue (true, eBroadcastAlways);
209 
210     while (state == eStateRunning)
211     {
212         log = ProcessGDBRemoteLog::GetLogIfAllCategoriesSet (GDBR_LOG_PROCESS);
213         if (log)
214             log->Printf ("GDBRemoteCommunication::%s () WaitForPacket(...)", __FUNCTION__);
215 
216         if (WaitForPacket (response, (TimeValue*)NULL))
217         {
218             log = ProcessGDBRemoteLog::GetLogIfAllCategoriesSet (GDBR_LOG_PROCESS);
219             async_log = ProcessGDBRemoteLog::GetLogIfAllCategoriesSet (GDBR_LOG_ASYNC);
220             if (response.Empty())
221                 state = eStateInvalid;
222             else
223             {
224                 const char stop_type = response.GetChar();
225                 if (log)
226                     log->Printf ("GDBRemoteCommunication::%s () got '%c' packet", __FUNCTION__, stop_type);
227                 switch (stop_type)
228                 {
229                 case 'T':
230                 case 'S':
231                     if (m_async_signal != -1)
232                     {
233                         if (async_log)
234                             async_log->Printf ("async: send signo = %s", Host::GetSignalAsCString (m_async_signal));
235 
236                         // Save off the async signal we are supposed to send
237                         const int async_signal = m_async_signal;
238                         // Clear the async signal member so we don't end up
239                         // sending the signal multiple times...
240                         m_async_signal = -1;
241                         // Check which signal we stopped with
242                         uint8_t signo = response.GetHexU8(255);
243                         if (signo == async_signal)
244                         {
245                             if (async_log)
246                                 async_log->Printf ("async: stopped with signal %s, we are done running", Host::GetSignalAsCString (signo));
247 
248                             // We already stopped with a signal that we wanted
249                             // to stop with, so we are done
250                             response.SetFilePos (0);
251                         }
252                         else
253                         {
254                             // We stopped with a different signal that the one
255                             // we wanted to stop with, so now we must resume
256                             // with the signal we want
257                             char signal_packet[32];
258                             int signal_packet_len = 0;
259                             signal_packet_len = ::snprintf (signal_packet,
260                                                             sizeof (signal_packet),
261                                                             "C%2.2x",
262                                                             async_signal);
263 
264                             if (async_log)
265                                 async_log->Printf ("async: stopped with signal %s, resume with %s",
266                                                    Host::GetSignalAsCString (signo),
267                                                    Host::GetSignalAsCString (async_signal));
268 
269                             if (SendPacket(signal_packet, signal_packet_len) == 0)
270                             {
271                                 if (async_log)
272                                     async_log->Printf ("async: error: failed to resume with %s",
273                                                        Host::GetSignalAsCString (async_signal));
274                                 state = eStateInvalid;
275                                 break;
276                             }
277                             else
278                                 continue;
279                         }
280                     }
281                     else if (m_async_packet_predicate.GetValue())
282                     {
283                         if (async_log)
284                             async_log->Printf ("async: send async packet: %s",
285                                                m_async_packet.c_str());
286 
287                         // We are supposed to send an asynchronous packet while
288                         // we are running.
289                         m_async_response.Clear();
290                         if (!m_async_packet.empty())
291                         {
292                             SendPacketAndWaitForResponse (&m_async_packet[0],
293                                                           m_async_packet.size(),
294                                                           m_async_response,
295                                                           m_async_timeout,
296                                                           false);
297                         }
298                         // Let the other thread that was trying to send the async
299                         // packet know that the packet has been sent.
300                         m_async_packet_predicate.SetValue(false, eBroadcastAlways);
301 
302                         if (async_log)
303                             async_log->Printf ("async: resume after async response received: %s",
304                                                m_async_response.GetStringRef().c_str());
305 
306                         // Continue again
307                         if (SendPacket("c", 1) == 0)
308                         {
309                             state = eStateInvalid;
310                             break;
311                         }
312                         else
313                             continue;
314                     }
315                     // Stop with signal and thread info
316                     state = eStateStopped;
317                     break;
318 
319                 case 'W':
320                     // process exited
321                     state = eStateExited;
322                     break;
323 
324                 case 'O':
325                     // STDOUT
326                     {
327                         std::string inferior_stdout;
328                         inferior_stdout.reserve(response.GetBytesLeft () / 2);
329                         char ch;
330                         while ((ch = response.GetHexU8()) != '\0')
331                             inferior_stdout.append(1, ch);
332                         process->AppendSTDOUT (inferior_stdout.c_str(), inferior_stdout.size());
333                     }
334                     break;
335 
336                 case 'E':
337                     // ERROR
338                     state = eStateInvalid;
339                     break;
340 
341                 default:
342                     if (log)
343                         log->Printf ("GDBRemoteCommunication::%s () got unrecognized async packet: '%s'", __FUNCTION__, stop_type);
344                     break;
345                 }
346             }
347         }
348         else
349         {
350             log = ProcessGDBRemoteLog::GetLogIfAllCategoriesSet (GDBR_LOG_PROCESS);
351             if (log)
352                 log->Printf ("GDBRemoteCommunication::%s () WaitForPacket(...) => false", __FUNCTION__);
353             state = eStateInvalid;
354         }
355     }
356     log = ProcessGDBRemoteLog::GetLogIfAllCategoriesSet (GDBR_LOG_PROCESS);
357     if (log)
358         log->Printf ("GDBRemoteCommunication::%s () => %s", __FUNCTION__, StateAsCString(state));
359     response.SetFilePos(0);
360     m_is_running.SetValue (false, eBroadcastOnChange);
361     return state;
362 }
363 
364 size_t
365 GDBRemoteCommunication::SendPacket (const char *payload)
366 {
367     Mutex::Locker locker(m_sequence_mutex);
368     return SendPacketNoLock (payload, ::strlen (payload));
369 }
370 
371 size_t
372 GDBRemoteCommunication::SendPacket (const char *payload, size_t payload_length)
373 {
374     Mutex::Locker locker(m_sequence_mutex);
375     return SendPacketNoLock (payload, payload_length);
376 }
377 
378 size_t
379 GDBRemoteCommunication::SendPacketNoLock (const char *payload, size_t payload_length)
380 {
381     if (IsConnected())
382     {
383         StreamString packet(0, 4, eByteOrderBig);
384 
385         packet.PutChar('$');
386         packet.Write (payload, payload_length);
387         packet.PutChar('#');
388         packet.PutHex8(CalculcateChecksum (payload, payload_length));
389 
390         ProcessGDBRemoteLog::LogIf (GDBR_LOG_PACKETS, "send packet: %s", packet.GetData());
391         ConnectionStatus status = eConnectionStatusSuccess;
392         size_t bytes_written = Write (packet.GetData(), packet.GetSize(), status, NULL);
393         if (bytes_written == packet.GetSize())
394         {
395             if (m_send_acks)
396             {
397                 if (GetAck (1) != '+')
398                     return 0;
399             }
400         }
401         else
402         {
403             ProcessGDBRemoteLog::LogIf (GDBR_LOG_PACKETS, "error: failed to send packet: %s", packet.GetData());
404         }
405         return bytes_written;
406     }
407     return 0;
408 }
409 
410 char
411 GDBRemoteCommunication::GetAck (uint32_t timeout_seconds)
412 {
413     StringExtractorGDBRemote response;
414     if (WaitForPacket (response, timeout_seconds) == 1)
415         return response.GetChar();
416     return 0;
417 }
418 
419 bool
420 GDBRemoteCommunication::GetSequenceMutex (Mutex::Locker& locker)
421 {
422     return locker.TryLock (m_sequence_mutex.GetMutex());
423 }
424 
425 bool
426 GDBRemoteCommunication::SendAsyncSignal (int signo)
427 {
428     m_async_signal = signo;
429     bool timed_out = false;
430     Mutex::Locker locker;
431     if (SendInterrupt (locker, 1, &timed_out))
432         return true;
433     m_async_signal = -1;
434     return false;
435 }
436 
437 // This function takes a mutex locker as a parameter in case the GetSequenceMutex
438 // actually succeeds. If it doesn't succeed in acquiring the sequence mutex
439 // (the expected result), then it will send the halt packet. If it does succeed
440 // then the caller that requested the interrupt will want to keep the sequence
441 // locked down so that no one else can send packets while the caller has control.
442 // This function usually gets called when we are running and need to stop the
443 // target. It can also be used when we are running and and we need to do something
444 // else (like read/write memory), so we need to interrupt the running process
445 // (gdb remote protocol requires this), and do what we need to do, then resume.
446 
447 bool
448 GDBRemoteCommunication::SendInterrupt (Mutex::Locker& locker, uint32_t seconds_to_wait_for_stop, bool *timed_out)
449 {
450     if (timed_out)
451         *timed_out = false;
452 
453     if (IsConnected() && IsRunning())
454     {
455         // Only send an interrupt if our debugserver is running...
456         if (GetSequenceMutex (locker) == false)
457         {
458             // Someone has the mutex locked waiting for a response or for the
459             // inferior to stop, so send the interrupt on the down low...
460             char ctrl_c = '\x03';
461             ConnectionStatus status = eConnectionStatusSuccess;
462             TimeValue timeout;
463             if (seconds_to_wait_for_stop)
464             {
465                 timeout = TimeValue::Now();
466                 timeout.OffsetWithSeconds (seconds_to_wait_for_stop);
467             }
468             ProcessGDBRemoteLog::LogIf (GDBR_LOG_PACKETS, "send packet: \\x03");
469             if (Write (&ctrl_c, 1, status, NULL) > 0)
470             {
471                 if (seconds_to_wait_for_stop)
472                     m_is_running.WaitForValueEqualTo (false, &timeout, timed_out);
473                 return true;
474             }
475         }
476     }
477     return false;
478 }
479 
480 size_t
481 GDBRemoteCommunication::WaitForPacket (StringExtractorGDBRemote &response, uint32_t timeout_seconds)
482 {
483     TimeValue timeout_time;
484     timeout_time = TimeValue::Now();
485     timeout_time.OffsetWithSeconds (timeout_seconds);
486     return WaitForPacketNoLock (response, &timeout_time);
487 }
488 
489 size_t
490 GDBRemoteCommunication::WaitForPacket (StringExtractorGDBRemote &response, TimeValue* timeout_time_ptr)
491 {
492     Mutex::Locker locker(m_sequence_mutex);
493     return WaitForPacketNoLock (response, timeout_time_ptr);
494 }
495 
496 size_t
497 GDBRemoteCommunication::WaitForPacketNoLock (StringExtractorGDBRemote &response, TimeValue* timeout_time_ptr)
498 {
499     bool checksum_error = false;
500     response.Clear ();
501 
502     EventSP event_sp;
503 
504     if (m_rx_packet_listener.WaitForEvent (timeout_time_ptr, event_sp))
505     {
506         const uint32_t event_type = event_sp->GetType();
507         if (event_type | Communication::eBroadcastBitPacketAvailable)
508         {
509             const EventDataBytes *event_bytes = EventDataBytes::GetEventDataFromEvent(event_sp.get());
510             if (event_bytes)
511             {
512                 const char * packet_data =  (const char *)event_bytes->GetBytes();
513                 ProcessGDBRemoteLog::LogIf (GDBR_LOG_PACKETS, "read packet: %s", packet_data);
514                 const size_t packet_size =  event_bytes->GetByteSize();
515                 if (packet_data && packet_size > 0)
516                 {
517                     std::string &response_str = response.GetStringRef();
518                     if (packet_data[0] == '$')
519                     {
520                         assert (packet_size >= 4);  // Must have at least '$#CC' where CC is checksum
521                         assert (packet_data[packet_size-3] == '#');
522                         assert (::isxdigit (packet_data[packet_size-2]));  // Must be checksum hex byte
523                         assert (::isxdigit (packet_data[packet_size-1]));  // Must be checksum hex byte
524                         response_str.assign (packet_data + 1, packet_size - 4);
525                         if (m_send_acks)
526                         {
527                             char packet_checksum = strtol (&packet_data[packet_size-2], NULL, 16);
528                             char actual_checksum = CalculcateChecksum (&response_str[0], response_str.size());
529                             checksum_error = packet_checksum != actual_checksum;
530                             // Send the ack or nack if needed
531                             if (checksum_error)
532                                 SendAck('-');
533                             else
534                                 SendAck('+');
535                         }
536                     }
537                     else
538                     {
539                         response_str.assign (packet_data, packet_size);
540                     }
541                     return response_str.size();
542                 }
543             }
544         }
545         else if (Communication::eBroadcastBitReadThreadDidExit)
546         {
547             // Our read thread exited on us so just fall through and return zero...
548         }
549     }
550     return 0;
551 }
552 
553 void
554 GDBRemoteCommunication::AppendBytesToCache (const uint8_t *src, size_t src_len, bool broadcast,
555                                             ConnectionStatus status)
556 {
557     // Put the packet data into the buffer in a thread safe fashion
558     Mutex::Locker locker(m_bytes_mutex);
559     m_bytes.append ((const char *)src, src_len);
560 
561     // Parse up the packets into gdb remote packets
562     while (!m_bytes.empty())
563     {
564         // end_idx must be one past the last valid packet byte. Start
565         // it off with an invalid value that is the same as the current
566         // index.
567         size_t end_idx = 0;
568 
569         switch (m_bytes[0])
570         {
571             case '+':       // Look for ack
572             case '-':       // Look for cancel
573             case '\x03':    // ^C to halt target
574                 end_idx = 1;  // The command is one byte long...
575                 break;
576 
577             case '$':
578                 // Look for a standard gdb packet?
579                 end_idx = m_bytes.find('#');
580                 if (end_idx != std::string::npos)
581                 {
582                     if (end_idx + 2 < m_bytes.size())
583                     {
584                         end_idx += 3;
585                     }
586                     else
587                     {
588                         // Checksum bytes aren't all here yet
589                         end_idx = std::string::npos;
590                     }
591                 }
592                 break;
593 
594             default:
595                 break;
596         }
597 
598         if (end_idx == std::string::npos)
599         {
600             //ProcessGDBRemoteLog::LogIf (GDBR_LOG_PACKETS | GDBR_LOG_VERBOSE, "GDBRemoteCommunication::%s packet not yet complete: '%s'",__FUNCTION__, m_bytes.c_str());
601             return;
602         }
603         else if (end_idx > 0)
604         {
605             // We have a valid packet...
606             assert (end_idx <= m_bytes.size());
607             std::auto_ptr<EventDataBytes> event_bytes_ap (new EventDataBytes (&m_bytes[0], end_idx));
608             ProcessGDBRemoteLog::LogIf (GDBR_LOG_COMM, "got full packet: %s", event_bytes_ap->GetBytes());
609             BroadcastEvent (eBroadcastBitPacketAvailable, event_bytes_ap.release());
610             m_bytes.erase(0, end_idx);
611         }
612         else
613         {
614             assert (1 <= m_bytes.size());
615             ProcessGDBRemoteLog::LogIf (GDBR_LOG_COMM, "GDBRemoteCommunication::%s tossing junk byte at %c",__FUNCTION__, m_bytes[0]);
616             m_bytes.erase(0, 1);
617         }
618     }
619 }
620 
621 lldb::pid_t
622 GDBRemoteCommunication::GetCurrentProcessID (uint32_t timeout_seconds)
623 {
624     StringExtractorGDBRemote response;
625     if (SendPacketAndWaitForResponse("qC", strlen("qC"), response, timeout_seconds, false))
626     {
627         if (response.GetChar() == 'Q')
628             if (response.GetChar() == 'C')
629                 return response.GetHexMaxU32 (false, LLDB_INVALID_PROCESS_ID);
630     }
631     return LLDB_INVALID_PROCESS_ID;
632 }
633 
634 bool
635 GDBRemoteCommunication::GetLaunchSuccess (uint32_t timeout_seconds, std::string &error_str)
636 {
637     error_str.clear();
638     StringExtractorGDBRemote response;
639     if (SendPacketAndWaitForResponse("qLaunchSuccess", strlen("qLaunchSuccess"), response, timeout_seconds, false))
640     {
641         if (response.IsOKPacket())
642             return true;
643         if (response.GetChar() == 'E')
644         {
645             // A string the describes what failed when launching...
646             error_str = response.GetStringRef().substr(1);
647         }
648         else
649         {
650             error_str.assign ("unknown error occurred launching process");
651         }
652     }
653     else
654     {
655         error_str.assign ("failed to send the qLaunchSuccess packet");
656     }
657     return false;
658 }
659 
660 int
661 GDBRemoteCommunication::SendArgumentsPacket (char const *argv[], uint32_t timeout_seconds)
662 {
663     if (argv && argv[0])
664     {
665         StreamString packet;
666         packet.PutChar('A');
667         const char *arg;
668         for (uint32_t i = 0; (arg = argv[i]) != NULL; ++i)
669         {
670             const int arg_len = strlen(arg);
671             if (i > 0)
672                 packet.PutChar(',');
673             packet.Printf("%i,%i,", arg_len * 2, i);
674             packet.PutBytesAsRawHex8(arg, arg_len, eByteOrderHost, eByteOrderHost);
675         }
676 
677         StringExtractorGDBRemote response;
678         if (SendPacketAndWaitForResponse (packet.GetData(), packet.GetSize(), response, timeout_seconds, false))
679         {
680             if (response.IsOKPacket())
681                 return 0;
682             uint8_t error = response.GetError();
683             if (error)
684                 return error;
685         }
686     }
687     return -1;
688 }
689 
690 int
691 GDBRemoteCommunication::SendEnvironmentPacket (char const *name_equal_value, uint32_t timeout_seconds)
692 {
693     if (name_equal_value && name_equal_value[0])
694     {
695         StreamString packet;
696         packet.Printf("QEnvironment:%s", name_equal_value);
697         StringExtractorGDBRemote response;
698         if (SendPacketAndWaitForResponse (packet.GetData(), packet.GetSize(), response, timeout_seconds, false))
699         {
700             if (response.IsOKPacket())
701                 return 0;
702             uint8_t error = response.GetError();
703             if (error)
704                 return error;
705         }
706     }
707     return -1;
708 }
709 
710 bool
711 GDBRemoteCommunication::GetHostInfo (uint32_t timeout_seconds)
712 {
713     m_arch.Clear();
714     m_os.Clear();
715     m_vendor.Clear();
716     m_byte_order = eByteOrderHost;
717     m_pointer_byte_size = 0;
718 
719     StringExtractorGDBRemote response;
720     if (SendPacketAndWaitForResponse ("qHostInfo", response, timeout_seconds, false))
721     {
722         if (response.IsUnsupportedPacket())
723             return false;
724 
725 
726         std::string name;
727         std::string value;
728         while (response.GetNameColonValue(name, value))
729         {
730             if (name.compare("cputype") == 0)
731             {
732                 // exception type in big endian hex
733                 m_arch.SetCPUType(Args::StringToUInt32 (value.c_str(), LLDB_INVALID_CPUTYPE, 0));
734             }
735             else if (name.compare("cpusubtype") == 0)
736             {
737                 // exception count in big endian hex
738                 m_arch.SetCPUSubtype(Args::StringToUInt32 (value.c_str(), 0, 0));
739             }
740             else if (name.compare("ostype") == 0)
741             {
742                 // exception data in big endian hex
743                 m_os.SetCString(value.c_str());
744             }
745             else if (name.compare("vendor") == 0)
746             {
747                 m_vendor.SetCString(value.c_str());
748             }
749             else if (name.compare("endian") == 0)
750             {
751                 if (value.compare("little") == 0)
752                     m_byte_order = eByteOrderLittle;
753                 else if (value.compare("big") == 0)
754                     m_byte_order = eByteOrderBig;
755                 else if (value.compare("pdp") == 0)
756                     m_byte_order = eByteOrderPDP;
757             }
758             else if (name.compare("ptrsize") == 0)
759             {
760                 m_pointer_byte_size = Args::StringToUInt32 (value.c_str(), 0, 0);
761             }
762         }
763     }
764     return HostInfoIsValid();
765 }
766 
767 int
768 GDBRemoteCommunication::SendAttach
769 (
770     lldb::pid_t pid,
771     uint32_t timeout_seconds,
772     StringExtractorGDBRemote& response
773 )
774 {
775     if (pid != LLDB_INVALID_PROCESS_ID)
776     {
777         StreamString packet;
778         packet.Printf("vAttach;%x", pid);
779 
780         if (SendPacketAndWaitForResponse (packet.GetData(), packet.GetSize(), response, timeout_seconds, false))
781         {
782             if (response.IsErrorPacket())
783                 return response.GetError();
784             return 0;
785         }
786     }
787     return -1;
788 }
789 
790 const lldb_private::ArchSpec &
791 GDBRemoteCommunication::GetHostArchitecture ()
792 {
793     if (!HostInfoIsValid ())
794         GetHostInfo (1);
795     return m_arch;
796 }
797 
798 const lldb_private::ConstString &
799 GDBRemoteCommunication::GetOSString ()
800 {
801     if (!HostInfoIsValid ())
802         GetHostInfo (1);
803     return m_os;
804 }
805 
806 const lldb_private::ConstString &
807 GDBRemoteCommunication::GetVendorString()
808 {
809     if (!HostInfoIsValid ())
810         GetHostInfo (1);
811     return m_vendor;
812 }
813 
814 lldb::ByteOrder
815 GDBRemoteCommunication::GetByteOrder ()
816 {
817     if (!HostInfoIsValid ())
818         GetHostInfo (1);
819     return m_byte_order;
820 }
821 
822 uint32_t
823 GDBRemoteCommunication::GetAddressByteSize ()
824 {
825     if (!HostInfoIsValid ())
826         GetHostInfo (1);
827     return m_pointer_byte_size;
828 }
829 
830 addr_t
831 GDBRemoteCommunication::AllocateMemory (size_t size, uint32_t permissions, uint32_t timeout_seconds)
832 {
833     char packet[64];
834     ::snprintf (packet, sizeof(packet), "_M%zx,%s%s%s", size,
835                 permissions & lldb::ePermissionsReadable ? "r" : "",
836                 permissions & lldb::ePermissionsWritable ? "w" : "",
837                 permissions & lldb::ePermissionsExecutable ? "x" : "");
838     StringExtractorGDBRemote response;
839     if (SendPacketAndWaitForResponse (packet, response, timeout_seconds, false))
840     {
841         if (!response.IsErrorPacket())
842             return response.GetHexMaxU64(false, LLDB_INVALID_ADDRESS);
843     }
844     return LLDB_INVALID_ADDRESS;
845 }
846 
847 bool
848 GDBRemoteCommunication::DeallocateMemory (addr_t addr, uint32_t timeout_seconds)
849 {
850     char packet[64];
851     snprintf(packet, sizeof(packet), "_m%llx", (uint64_t)addr);
852     StringExtractorGDBRemote response;
853     if (SendPacketAndWaitForResponse (packet, response, timeout_seconds, false))
854     {
855         if (!response.IsOKPacket())
856             return true;
857     }
858     return false;
859 }
860 
861 bool
862 GDBRemoteCommunication::WaitForIsRunning (uint32_t timeout_sec)
863 {
864     TimeValue timeout;
865     if (timeout_sec)
866     {
867         timeout = TimeValue::Now();
868         timeout.OffsetWithSeconds (timeout_sec);
869     }
870     bool timed_out = false;
871     m_is_running.WaitForValueEqualTo (true, &timeout, &timed_out);
872     return timed_out;
873 }
874 
875 
876