1 //===-- GDBRemoteCommunication.cpp ------------------------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
11 #include "GDBRemoteCommunication.h"
19 // Other libraries and framework includes
20 #include "lldb/Core/Log.h"
21 #include "lldb/Core/RegularExpression.h"
22 #include "lldb/Core/StreamFile.h"
23 #include "lldb/Core/StreamString.h"
24 #include "lldb/Host/ConnectionFileDescriptor.h"
25 #include "lldb/Host/FileSpec.h"
26 #include "lldb/Host/Host.h"
27 #include "lldb/Host/HostInfo.h"
28 #include "lldb/Host/Pipe.h"
29 #include "lldb/Host/Socket.h"
30 #include "lldb/Host/StringConvert.h"
31 #include "lldb/Host/ThreadLauncher.h"
32 #include "lldb/Host/TimeValue.h"
33 #include "lldb/Target/Platform.h"
34 #include "lldb/Target/Process.h"
35 #include "llvm/ADT/SmallString.h"
38 #include "ProcessGDBRemoteLog.h"
40 #if defined(__APPLE__)
41 # define DEBUGSERVER_BASENAME "debugserver"
43 # define DEBUGSERVER_BASENAME "lldb-server"
46 #if defined (HAVE_LIBCOMPRESSION)
47 #include <compression.h>
50 #if defined (HAVE_LIBZ)
55 using namespace lldb_private;
56 using namespace lldb_private::process_gdb_remote;
58 GDBRemoteCommunication::History::History (uint32_t size) :
61 m_total_packet_count (0),
62 m_dumped_to_log (false)
64 m_packets.resize(size);
67 GDBRemoteCommunication::History::~History ()
72 GDBRemoteCommunication::History::AddPacket (char packet_char,
74 uint32_t bytes_transmitted)
76 const size_t size = m_packets.size();
79 const uint32_t idx = GetNextIndex();
80 m_packets[idx].packet.assign (1, packet_char);
81 m_packets[idx].type = type;
82 m_packets[idx].bytes_transmitted = bytes_transmitted;
83 m_packets[idx].packet_idx = m_total_packet_count;
84 m_packets[idx].tid = Host::GetCurrentThreadID();
89 GDBRemoteCommunication::History::AddPacket (const std::string &src,
92 uint32_t bytes_transmitted)
94 const size_t size = m_packets.size();
97 const uint32_t idx = GetNextIndex();
98 m_packets[idx].packet.assign (src, 0, src_len);
99 m_packets[idx].type = type;
100 m_packets[idx].bytes_transmitted = bytes_transmitted;
101 m_packets[idx].packet_idx = m_total_packet_count;
102 m_packets[idx].tid = Host::GetCurrentThreadID();
107 GDBRemoteCommunication::History::Dump (Stream &strm) const
109 const uint32_t size = GetNumPacketsInHistory ();
110 const uint32_t first_idx = GetFirstSavedPacketIndex ();
111 const uint32_t stop_idx = m_curr_idx + size;
112 for (uint32_t i = first_idx; i < stop_idx; ++i)
114 const uint32_t idx = NormalizeIndex (i);
115 const Entry &entry = m_packets[idx];
116 if (entry.type == ePacketTypeInvalid || entry.packet.empty())
118 strm.Printf ("history[%u] tid=0x%4.4" PRIx64 " <%4u> %s packet: %s\n",
121 entry.bytes_transmitted,
122 (entry.type == ePacketTypeSend) ? "send" : "read",
123 entry.packet.c_str());
128 GDBRemoteCommunication::History::Dump (Log *log) const
130 if (log && !m_dumped_to_log)
132 m_dumped_to_log = true;
133 const uint32_t size = GetNumPacketsInHistory ();
134 const uint32_t first_idx = GetFirstSavedPacketIndex ();
135 const uint32_t stop_idx = m_curr_idx + size;
136 for (uint32_t i = first_idx; i < stop_idx; ++i)
138 const uint32_t idx = NormalizeIndex (i);
139 const Entry &entry = m_packets[idx];
140 if (entry.type == ePacketTypeInvalid || entry.packet.empty())
142 log->Printf ("history[%u] tid=0x%4.4" PRIx64 " <%4u> %s packet: %s",
145 entry.bytes_transmitted,
146 (entry.type == ePacketTypeSend) ? "send" : "read",
147 entry.packet.c_str());
152 //----------------------------------------------------------------------
153 // GDBRemoteCommunication constructor
154 //----------------------------------------------------------------------
155 GDBRemoteCommunication::GDBRemoteCommunication(const char *comm_name,
156 const char *listener_name) :
157 Communication(comm_name),
158 #ifdef LLDB_CONFIGURATION_DEBUG
159 m_packet_timeout (1000),
161 m_packet_timeout (1),
164 m_supports_qEcho (eLazyBoolCalculate),
165 m_sequence_mutex (Mutex::eMutexTypeRecursive),
166 m_public_is_running (false),
167 m_private_is_running (false),
170 m_compression_type (CompressionType::None),
175 //----------------------------------------------------------------------
177 //----------------------------------------------------------------------
178 GDBRemoteCommunication::~GDBRemoteCommunication()
185 // Stop the communications read thread which is used to parse all
186 // incoming packets. This function will block until the read
188 if (m_read_thread_enabled)
193 GDBRemoteCommunication::CalculcateChecksum (const char *payload, size_t payload_length)
197 for (size_t i = 0; i < payload_length; ++i)
198 checksum += payload[i];
200 return checksum & 255;
204 GDBRemoteCommunication::SendAck ()
206 Log *log (ProcessGDBRemoteLog::GetLogIfAllCategoriesSet (GDBR_LOG_PACKETS));
207 ConnectionStatus status = eConnectionStatusSuccess;
209 const size_t bytes_written = Write (&ch, 1, status, NULL);
211 log->Printf ("<%4" PRIu64 "> send packet: %c", (uint64_t)bytes_written, ch);
212 m_history.AddPacket (ch, History::ePacketTypeSend, bytes_written);
213 return bytes_written;
217 GDBRemoteCommunication::SendNack ()
219 Log *log (ProcessGDBRemoteLog::GetLogIfAllCategoriesSet (GDBR_LOG_PACKETS));
220 ConnectionStatus status = eConnectionStatusSuccess;
222 const size_t bytes_written = Write (&ch, 1, status, NULL);
224 log->Printf("<%4" PRIu64 "> send packet: %c", (uint64_t)bytes_written, ch);
225 m_history.AddPacket (ch, History::ePacketTypeSend, bytes_written);
226 return bytes_written;
229 GDBRemoteCommunication::PacketResult
230 GDBRemoteCommunication::SendPacket (const char *payload, size_t payload_length)
232 Mutex::Locker locker(m_sequence_mutex);
233 return SendPacketNoLock (payload, payload_length);
236 GDBRemoteCommunication::PacketResult
237 GDBRemoteCommunication::SendPacketNoLock (const char *payload, size_t payload_length)
241 StreamString packet(0, 4, eByteOrderBig);
244 packet.Write (payload, payload_length);
246 packet.PutHex8(CalculcateChecksum (payload, payload_length));
248 Log *log (ProcessGDBRemoteLog::GetLogIfAllCategoriesSet (GDBR_LOG_PACKETS));
249 ConnectionStatus status = eConnectionStatusSuccess;
250 const char *packet_data = packet.GetData();
251 const size_t packet_length = packet.GetSize();
252 size_t bytes_written = Write (packet_data, packet_length, status, NULL);
255 size_t binary_start_offset = 0;
256 if (strncmp(packet_data, "$vFile:pwrite:", strlen("$vFile:pwrite:")) == 0)
258 const char *first_comma = strchr(packet_data, ',');
261 const char *second_comma = strchr(first_comma + 1, ',');
263 binary_start_offset = second_comma - packet_data + 1;
267 // If logging was just enabled and we have history, then dump out what
268 // we have to the log so we get the historical context. The Dump() call that
269 // logs all of the packet will set a boolean so that we don't dump this more
271 if (!m_history.DidDumpToLog ())
272 m_history.Dump (log);
274 if (binary_start_offset)
277 // Print non binary data header
278 strm.Printf("<%4" PRIu64 "> send packet: %.*s", (uint64_t)bytes_written, (int)binary_start_offset, packet_data);
280 // Print binary data exactly as sent
281 for (p = (const uint8_t*)packet_data + binary_start_offset; *p != '#'; ++p)
282 strm.Printf("\\x%2.2x", *p);
283 // Print the checksum
284 strm.Printf("%*s", (int)3, p);
285 log->PutCString(strm.GetString().c_str());
288 log->Printf("<%4" PRIu64 "> send packet: %.*s", (uint64_t)bytes_written, (int)packet_length, packet_data);
291 m_history.AddPacket (packet.GetString(), packet_length, History::ePacketTypeSend, bytes_written);
294 if (bytes_written == packet_length)
299 return PacketResult::Success;
304 log->Printf ("error: failed to send packet: %.*s", (int)packet_length, packet_data);
307 return PacketResult::ErrorSendFailed;
310 GDBRemoteCommunication::PacketResult
311 GDBRemoteCommunication::GetAck ()
313 StringExtractorGDBRemote packet;
314 PacketResult result = ReadPacket (packet, GetPacketTimeoutInMicroSeconds (), false);
315 if (result == PacketResult::Success)
317 if (packet.GetResponseType() == StringExtractorGDBRemote::ResponseType::eAck)
318 return PacketResult::Success;
320 return PacketResult::ErrorSendAck;
326 GDBRemoteCommunication::GetSequenceMutex (Mutex::Locker& locker, const char *failure_message)
329 return locker.TryLock (m_sequence_mutex, failure_message);
331 locker.Lock (m_sequence_mutex);
337 GDBRemoteCommunication::WaitForNotRunningPrivate (const TimeValue *timeout_ptr)
339 return m_private_is_running.WaitForValueEqualTo (false, timeout_ptr, NULL);
342 GDBRemoteCommunication::PacketResult
343 GDBRemoteCommunication::ReadPacket (StringExtractorGDBRemote &response, uint32_t timeout_usec, bool sync_on_timeout)
345 if (m_read_thread_enabled)
346 return PopPacketFromQueue (response, timeout_usec);
348 return WaitForPacketWithTimeoutMicroSecondsNoLock (response, timeout_usec, sync_on_timeout);
352 // This function is called when a packet is requested.
353 // A whole packet is popped from the packet queue and returned to the caller.
354 // Packets are placed into this queue from the communication read thread.
355 // See GDBRemoteCommunication::AppendBytesToCache.
356 GDBRemoteCommunication::PacketResult
357 GDBRemoteCommunication::PopPacketFromQueue (StringExtractorGDBRemote &response, uint32_t timeout_usec)
359 // Calculate absolute timeout value
360 TimeValue timeout = TimeValue::Now();
361 timeout.OffsetWithMicroSeconds(timeout_usec);
365 // scope for the mutex
367 // lock down the packet queue
368 Mutex::Locker locker(m_packet_queue_mutex);
370 // Wait on condition variable.
371 if (m_packet_queue.size() == 0)
372 m_condition_queue_not_empty.Wait(m_packet_queue_mutex, &timeout);
374 if (m_packet_queue.size() > 0)
376 // get the front element of the queue
377 response = m_packet_queue.front();
379 // remove the front element
380 m_packet_queue.pop();
383 return PacketResult::Success;
389 return PacketResult::ErrorDisconnected;
391 // Loop while not timed out
392 } while (TimeValue::Now() < timeout);
394 return PacketResult::ErrorReplyTimeout;
398 GDBRemoteCommunication::PacketResult
399 GDBRemoteCommunication::WaitForPacketWithTimeoutMicroSecondsNoLock (StringExtractorGDBRemote &packet, uint32_t timeout_usec, bool sync_on_timeout)
401 uint8_t buffer[8192];
404 Log *log (ProcessGDBRemoteLog::GetLogIfAllCategoriesSet (GDBR_LOG_PACKETS | GDBR_LOG_VERBOSE));
406 // Check for a packet from our cache first without trying any reading...
407 if (CheckForPacket(NULL, 0, packet) != PacketType::Invalid)
408 return PacketResult::Success;
410 bool timed_out = false;
411 bool disconnected = false;
412 while (IsConnected() && !timed_out)
414 lldb::ConnectionStatus status = eConnectionStatusNoConnection;
415 size_t bytes_read = Read (buffer, sizeof(buffer), timeout_usec, status, &error);
418 log->Printf ("%s: Read (buffer, (sizeof(buffer), timeout_usec = 0x%x, status = %s, error = %s) => bytes_read = %" PRIu64,
421 Communication::ConnectionStatusAsCString (status),
423 (uint64_t)bytes_read);
427 if (CheckForPacket(buffer, bytes_read, packet) != PacketType::Invalid)
428 return PacketResult::Success;
434 case eConnectionStatusTimedOut:
435 case eConnectionStatusInterrupted:
438 //------------------------------------------------------------------
439 /// Sync the remote GDB server and make sure we get a response that
440 /// corresponds to what we send.
442 /// Sends a "qEcho" packet and makes sure it gets the exact packet
443 /// echoed back. If the qEcho packet isn't supported, we send a qC
444 /// packet and make sure we get a valid thread ID back. We use the
445 /// "qC" packet since its response if very unique: is responds with
446 /// "QC%x" where %x is the thread ID of the current thread. This
447 /// makes the response unique enough from other packet responses to
448 /// ensure we are back on track.
450 /// This packet is needed after we time out sending a packet so we
451 /// can ensure that we are getting the response for the packet we
452 /// are sending. There are no sequence IDs in the GDB remote
453 /// protocol (there used to be, but they are not supported anymore)
454 /// so if you timeout sending packet "abc", you might then send
455 /// packet "cde" and get the response for the previous "abc" packet.
456 /// Many responses are "OK" or "" (unsupported) or "EXX" (error) so
457 /// many responses for packets can look like responses for other
458 /// packets. So if we timeout, we need to ensure that we can get
459 /// back on track. If we can't get back on track, we must
461 //------------------------------------------------------------------
462 bool sync_success = false;
463 bool got_actual_response = false;
464 // We timed out, we need to sync back up with the
465 char echo_packet[32];
466 int echo_packet_len = 0;
467 RegularExpression response_regex;
469 if (m_supports_qEcho == eLazyBoolYes)
471 echo_packet_len = ::snprintf (echo_packet, sizeof(echo_packet), "qEcho:%u", ++m_echo_number);
472 std::string regex_str = "^";
473 regex_str += echo_packet;
475 response_regex.Compile(regex_str.c_str());
479 echo_packet_len = ::snprintf (echo_packet, sizeof(echo_packet), "qC");
480 response_regex.Compile("^QC[0-9A-Fa-f]+$");
483 PacketResult echo_packet_result = SendPacketNoLock (echo_packet, echo_packet_len);
484 if (echo_packet_result == PacketResult::Success)
486 const uint32_t max_retries = 3;
487 uint32_t successful_responses = 0;
488 for (uint32_t i=0; i<max_retries; ++i)
490 StringExtractorGDBRemote echo_response;
491 echo_packet_result = WaitForPacketWithTimeoutMicroSecondsNoLock (echo_response, timeout_usec, false);
492 if (echo_packet_result == PacketResult::Success)
494 ++successful_responses;
495 if (response_regex.Execute(echo_response.GetStringRef().c_str()))
500 else if (successful_responses == 1)
502 // We got something else back as the first successful response, it probably is
503 // the response to the packet we actually wanted, so copy it over if this
504 // is the first success and continue to try to get the qEcho response
505 packet = echo_response;
506 got_actual_response = true;
509 else if (echo_packet_result == PacketResult::ErrorReplyTimeout)
510 continue; // Packet timed out, continue waiting for a response
512 break; // Something else went wrong getting the packet back, we failed and are done trying
516 // We weren't able to sync back up with the server, we must abort otherwise
517 // all responses might not be from the right packets...
520 // We timed out, but were able to recover
521 if (got_actual_response)
523 // We initially timed out, but we did get a response that came in before the successful
524 // reply to our qEcho packet, so lets say everything is fine...
525 return PacketResult::Success;
536 case eConnectionStatusSuccess:
537 //printf ("status = success but error = %s\n", error.AsCString("<invalid>"));
540 case eConnectionStatusEndOfFile:
541 case eConnectionStatusNoConnection:
542 case eConnectionStatusLostConnection:
543 case eConnectionStatusError:
552 return PacketResult::ErrorDisconnected;
554 return PacketResult::ErrorReplyTimeout;
556 return PacketResult::ErrorReplyFailed;
560 GDBRemoteCommunication::DecompressPacket ()
562 Log *log (ProcessGDBRemoteLog::GetLogIfAllCategoriesSet (GDBR_LOG_PACKETS));
564 if (!CompressionIsEnabled())
567 size_t pkt_size = m_bytes.size();
569 // Smallest possible compressed packet is $N#00 - an uncompressed empty reply, most commonly indicating
570 // an unsupported packet. Anything less than 5 characters, it's definitely not a compressed packet.
574 if (m_bytes[0] != '$' && m_bytes[0] != '%')
576 if (m_bytes[1] != 'C' && m_bytes[1] != 'N')
579 size_t hash_mark_idx = m_bytes.find ('#');
580 if (hash_mark_idx == std::string::npos)
582 if (hash_mark_idx + 2 >= m_bytes.size())
585 if (!::isxdigit (m_bytes[hash_mark_idx + 1]) || !::isxdigit (m_bytes[hash_mark_idx + 2]))
588 size_t content_length = pkt_size - 5; // not counting '$', 'C' | 'N', '#', & the two hex checksum chars
589 size_t content_start = 2; // The first character of the compressed/not-compressed text of the packet
590 size_t checksum_idx = hash_mark_idx + 1; // The first character of the two hex checksum characters
592 // Normally size_of_first_packet == m_bytes.size() but m_bytes may contain multiple packets.
593 // size_of_first_packet is the size of the initial packet which we'll replace with the decompressed
594 // version of, leaving the rest of m_bytes unmodified.
595 size_t size_of_first_packet = hash_mark_idx + 3;
597 // Compressed packets ("$C") start with a base10 number which is the size of the uncompressed payload,
598 // then a : and then the compressed data. e.g. $C1024:<binary>#00
599 // Update content_start and content_length to only include the <binary> part of the packet.
601 uint64_t decompressed_bufsize = ULONG_MAX;
602 if (m_bytes[1] == 'C')
604 size_t i = content_start;
605 while (i < hash_mark_idx && isdigit(m_bytes[i]))
607 if (i < hash_mark_idx && m_bytes[i] == ':')
611 content_length = hash_mark_idx - content_start;
612 std::string bufsize_str (m_bytes.data() + 2, i - 2 - 1);
614 decompressed_bufsize = ::strtoul (bufsize_str.c_str(), NULL, 10);
615 if (errno != 0 || decompressed_bufsize == ULONG_MAX)
617 m_bytes.erase (0, size_of_first_packet);
625 char packet_checksum_cstr[3];
626 packet_checksum_cstr[0] = m_bytes[checksum_idx];
627 packet_checksum_cstr[1] = m_bytes[checksum_idx + 1];
628 packet_checksum_cstr[2] = '\0';
629 long packet_checksum = strtol (packet_checksum_cstr, NULL, 16);
631 long actual_checksum = CalculcateChecksum (m_bytes.data() + 1, hash_mark_idx - 1);
632 bool success = packet_checksum == actual_checksum;
636 log->Printf ("error: checksum mismatch: %.*s expected 0x%2.2x, got 0x%2.2x",
639 (uint8_t)packet_checksum,
640 (uint8_t)actual_checksum);
642 // Send the ack or nack if needed
646 m_bytes.erase (0, size_of_first_packet);
655 if (m_bytes[1] == 'N')
657 // This packet was not compressed -- delete the 'N' character at the
658 // start and the packet may be processed as-is.
663 // Reverse the gdb-remote binary escaping that was done to the compressed text to
664 // guard characters like '$', '#', '}', etc.
665 std::vector<uint8_t> unescaped_content;
666 unescaped_content.reserve (content_length);
667 size_t i = content_start;
668 while (i < hash_mark_idx)
670 if (m_bytes[i] == '}')
673 unescaped_content.push_back (m_bytes[i] ^ 0x20);
677 unescaped_content.push_back (m_bytes[i]);
682 uint8_t *decompressed_buffer = nullptr;
683 size_t decompressed_bytes = 0;
685 if (decompressed_bufsize != ULONG_MAX)
687 decompressed_buffer = (uint8_t *) malloc (decompressed_bufsize + 1);
688 if (decompressed_buffer == nullptr)
690 m_bytes.erase (0, size_of_first_packet);
696 #if defined (HAVE_LIBCOMPRESSION)
697 // libcompression is weak linked so check that compression_decode_buffer() is available
698 if (compression_decode_buffer != NULL &&
699 (m_compression_type == CompressionType::ZlibDeflate
700 || m_compression_type == CompressionType::LZFSE
701 || m_compression_type == CompressionType::LZ4))
703 compression_algorithm compression_type;
704 if (m_compression_type == CompressionType::ZlibDeflate)
705 compression_type = COMPRESSION_ZLIB;
706 else if (m_compression_type == CompressionType::LZFSE)
707 compression_type = COMPRESSION_LZFSE;
708 else if (m_compression_type == CompressionType::LZ4)
709 compression_type = COMPRESSION_LZ4_RAW;
710 else if (m_compression_type == CompressionType::LZMA)
711 compression_type = COMPRESSION_LZMA;
714 // If we have the expected size of the decompressed payload, we can allocate
715 // the right-sized buffer and do it. If we don't have that information, we'll
716 // need to try decoding into a big buffer and if the buffer wasn't big enough,
717 // increase it and try again.
719 if (decompressed_bufsize != ULONG_MAX && decompressed_buffer != nullptr)
721 decompressed_bytes = compression_decode_buffer (decompressed_buffer, decompressed_bufsize + 10 ,
722 (uint8_t*) unescaped_content.data(),
723 unescaped_content.size(),
730 #if defined (HAVE_LIBZ)
731 if (decompressed_bytes == 0
732 && decompressed_bufsize != ULONG_MAX
733 && decompressed_buffer != nullptr
734 && m_compression_type == CompressionType::ZlibDeflate)
737 memset (&stream, 0, sizeof (z_stream));
738 stream.next_in = (Bytef *) unescaped_content.data();
739 stream.avail_in = (uInt) unescaped_content.size();
741 stream.next_out = (Bytef *) decompressed_buffer;
742 stream.avail_out = decompressed_bufsize;
743 stream.total_out = 0;
744 stream.zalloc = Z_NULL;
745 stream.zfree = Z_NULL;
746 stream.opaque = Z_NULL;
748 if (inflateInit2 (&stream, -15) == Z_OK)
750 int status = inflate (&stream, Z_NO_FLUSH);
751 inflateEnd (&stream);
752 if (status == Z_STREAM_END)
754 decompressed_bytes = stream.total_out;
760 if (decompressed_bytes == 0 || decompressed_buffer == nullptr)
762 if (decompressed_buffer)
763 free (decompressed_buffer);
764 m_bytes.erase (0, size_of_first_packet);
768 std::string new_packet;
769 new_packet.reserve (decompressed_bytes + 6);
770 new_packet.push_back (m_bytes[0]);
771 new_packet.append ((const char *) decompressed_buffer, decompressed_bytes);
772 new_packet.push_back ('#');
775 uint8_t decompressed_checksum = CalculcateChecksum ((const char *) decompressed_buffer, decompressed_bytes);
776 char decompressed_checksum_str[3];
777 snprintf (decompressed_checksum_str, 3, "%02x", decompressed_checksum);
778 new_packet.append (decompressed_checksum_str);
782 new_packet.push_back ('0');
783 new_packet.push_back ('0');
786 m_bytes.replace (0, size_of_first_packet, new_packet.data(), new_packet.size());
788 free (decompressed_buffer);
792 GDBRemoteCommunication::PacketType
793 GDBRemoteCommunication::CheckForPacket (const uint8_t *src, size_t src_len, StringExtractorGDBRemote &packet)
795 // Put the packet data into the buffer in a thread safe fashion
796 Mutex::Locker locker(m_bytes_mutex);
798 Log *log (ProcessGDBRemoteLog::GetLogIfAllCategoriesSet (GDBR_LOG_PACKETS));
800 if (src && src_len > 0)
802 if (log && log->GetVerbose())
805 log->Printf ("GDBRemoteCommunication::%s adding %u bytes: %.*s",
811 m_bytes.append ((const char *)src, src_len);
814 bool isNotifyPacket = false;
816 // Parse up the packets into gdb remote packets
817 if (!m_bytes.empty())
819 // end_idx must be one past the last valid packet byte. Start
820 // it off with an invalid value that is the same as the current
822 size_t content_start = 0;
823 size_t content_length = 0;
824 size_t total_length = 0;
825 size_t checksum_idx = std::string::npos;
827 // Size of packet before it is decompressed, for logging purposes
828 size_t original_packet_size = m_bytes.size();
829 if (CompressionIsEnabled())
831 if (DecompressPacket() == false)
834 return GDBRemoteCommunication::PacketType::Standard;
840 case '+': // Look for ack
841 case '-': // Look for cancel
842 case '\x03': // ^C to halt target
843 content_length = total_length = 1; // The command is one byte long...
846 case '%': // Async notify packet
847 isNotifyPacket = true;
848 // Intentional fall through
851 // Look for a standard gdb packet?
853 size_t hash_pos = m_bytes.find('#');
854 if (hash_pos != std::string::npos)
856 if (hash_pos + 2 < m_bytes.size())
858 checksum_idx = hash_pos + 1;
859 // Skip the dollar sign
861 // Don't include the # in the content or the $ in the content length
862 content_length = hash_pos - 1;
864 total_length = hash_pos + 3; // Skip the # and the two hex checksum bytes
868 // Checksum bytes aren't all here yet
869 content_length = std::string::npos;
877 // We have an unexpected byte and we need to flush all bad
878 // data that is in m_bytes, so we need to find the first
879 // byte that is a '+' (ACK), '-' (NACK), \x03 (CTRL+C interrupt),
880 // or '$' character (start of packet header) or of course,
881 // the end of the data in m_bytes...
882 const size_t bytes_len = m_bytes.size();
885 for (idx = 1; !done && idx < bytes_len; ++idx)
887 switch (m_bytes[idx])
902 log->Printf ("GDBRemoteCommunication::%s tossing %u junk bytes: '%.*s'",
903 __FUNCTION__, idx - 1, idx - 1, m_bytes.c_str());
904 m_bytes.erase(0, idx - 1);
909 if (content_length == std::string::npos)
912 return GDBRemoteCommunication::PacketType::Invalid;
914 else if (total_length > 0)
917 // We have a valid packet...
918 assert (content_length <= m_bytes.size());
919 assert (total_length <= m_bytes.size());
920 assert (content_length <= total_length);
921 size_t content_end = content_start + content_length;
924 std::string &packet_str = packet.GetStringRef();
927 // If logging was just enabled and we have history, then dump out what
928 // we have to the log so we get the historical context. The Dump() call that
929 // logs all of the packet will set a boolean so that we don't dump this more
931 if (!m_history.DidDumpToLog ())
932 m_history.Dump (log);
935 // Only detect binary for packets that start with a '$' and have a '#CC' checksum
936 if (m_bytes[0] == '$' && total_length > 4)
938 for (size_t i=0; !binary && i<total_length; ++i)
940 if (isprint (m_bytes[i]) == 0 && isspace (m_bytes[i]) == 0)
950 if (CompressionIsEnabled())
951 strm.Printf("<%4" PRIu64 ":%" PRIu64 "> read packet: %c", (uint64_t) original_packet_size, (uint64_t)total_length, m_bytes[0]);
953 strm.Printf("<%4" PRIu64 "> read packet: %c", (uint64_t)total_length, m_bytes[0]);
954 for (size_t i=content_start; i<content_end; ++i)
956 // Remove binary escaped bytes when displaying the packet...
957 const char ch = m_bytes[i];
960 // 0x7d is the escape character. The next character is to
961 // be XOR'd with 0x20.
962 const char escapee = m_bytes[++i] ^ 0x20;
963 strm.Printf("%2.2x", escapee);
967 strm.Printf("%2.2x", (uint8_t)ch);
971 strm.Printf("%c%c%c", m_bytes[total_length-3], m_bytes[total_length-2], m_bytes[total_length-1]);
972 log->PutCString(strm.GetString().c_str());
976 if (CompressionIsEnabled())
977 log->Printf("<%4" PRIu64 ":%" PRIu64 "> read packet: %.*s", (uint64_t) original_packet_size, (uint64_t)total_length, (int)(total_length), m_bytes.c_str());
979 log->Printf("<%4" PRIu64 "> read packet: %.*s", (uint64_t)total_length, (int)(total_length), m_bytes.c_str());
983 m_history.AddPacket (m_bytes.c_str(), total_length, History::ePacketTypeRecv, total_length);
985 // Clear packet_str in case there is some existing data in it.
987 // Copy the packet from m_bytes to packet_str expanding the
988 // run-length encoding in the process.
989 // Reserve enough byte for the most common case (no RLE used)
990 packet_str.reserve(m_bytes.length());
991 for (std::string::const_iterator c = m_bytes.begin() + content_start; c != m_bytes.begin() + content_end; ++c)
995 // '*' indicates RLE. Next character will give us the
996 // repeat count and previous character is what is to be
998 char char_to_repeat = packet_str.back();
999 // Number of time the previous character is repeated
1000 int repeat_count = *++c + 3 - ' ';
1001 // We have the char_to_repeat and repeat_count. Now push
1002 // it in the packet.
1003 for (int i = 0; i < repeat_count; ++i)
1004 packet_str.push_back(char_to_repeat);
1006 else if (*c == 0x7d)
1008 // 0x7d is the escape character. The next character is to
1009 // be XOR'd with 0x20.
1010 char escapee = *++c ^ 0x20;
1011 packet_str.push_back(escapee);
1015 packet_str.push_back(*c);
1019 if (m_bytes[0] == '$' || m_bytes[0] == '%')
1021 assert (checksum_idx < m_bytes.size());
1022 if (::isxdigit (m_bytes[checksum_idx+0]) ||
1023 ::isxdigit (m_bytes[checksum_idx+1]))
1027 const char *packet_checksum_cstr = &m_bytes[checksum_idx];
1028 char packet_checksum = strtol (packet_checksum_cstr, NULL, 16);
1029 char actual_checksum = CalculcateChecksum (packet_str.c_str(), packet_str.size());
1030 success = packet_checksum == actual_checksum;
1034 log->Printf ("error: checksum mismatch: %.*s expected 0x%2.2x, got 0x%2.2x",
1035 (int)(total_length),
1037 (uint8_t)packet_checksum,
1038 (uint8_t)actual_checksum);
1040 // Send the ack or nack if needed
1051 log->Printf ("error: invalid checksum in packet: '%s'\n", m_bytes.c_str());
1055 m_bytes.erase(0, total_length);
1056 packet.SetFilePos(0);
1059 return GDBRemoteCommunication::PacketType::Notify;
1061 return GDBRemoteCommunication::PacketType::Standard;
1065 return GDBRemoteCommunication::PacketType::Invalid;
1069 GDBRemoteCommunication::StartListenThread (const char *hostname, uint16_t port)
1072 if (m_listen_thread.IsJoinable())
1074 error.SetErrorString("listen thread already running");
1078 char listen_url[512];
1079 if (hostname && hostname[0])
1080 snprintf(listen_url, sizeof(listen_url), "listen://%s:%i", hostname, port);
1082 snprintf(listen_url, sizeof(listen_url), "listen://%i", port);
1083 m_listen_url = listen_url;
1084 SetConnection(new ConnectionFileDescriptor());
1085 m_listen_thread = ThreadLauncher::LaunchThread(listen_url, GDBRemoteCommunication::ListenThread, this, &error);
1091 GDBRemoteCommunication::JoinListenThread ()
1093 if (m_listen_thread.IsJoinable())
1094 m_listen_thread.Join(nullptr);
1098 lldb::thread_result_t
1099 GDBRemoteCommunication::ListenThread (lldb::thread_arg_t arg)
1101 GDBRemoteCommunication *comm = (GDBRemoteCommunication *)arg;
1103 ConnectionFileDescriptor *connection = (ConnectionFileDescriptor *)comm->GetConnection ();
1107 // Do the listen on another thread so we can continue on...
1108 if (connection->Connect(comm->m_listen_url.c_str(), &error) != eConnectionStatusSuccess)
1109 comm->SetConnection(NULL);
1115 GDBRemoteCommunication::StartDebugserverProcess (const char *url,
1117 ProcessLaunchInfo &launch_info,
1119 const Args& inferior_args)
1121 Log *log (ProcessGDBRemoteLog::GetLogIfAllCategoriesSet (GDBR_LOG_PROCESS));
1123 log->Printf ("GDBRemoteCommunication::%s(url=%s, port=%" PRIu16, __FUNCTION__, url ? url : "<empty>", port ? *port : uint16_t(0));
1126 // If we locate debugserver, keep that located version around
1127 static FileSpec g_debugserver_file_spec;
1129 char debugserver_path[PATH_MAX];
1130 FileSpec &debugserver_file_spec = launch_info.GetExecutableFile();
1132 // Always check to see if we have an environment override for the path
1133 // to the debugserver to use and use it if we do.
1134 const char *env_debugserver_path = getenv("LLDB_DEBUGSERVER_PATH");
1135 if (env_debugserver_path)
1137 debugserver_file_spec.SetFile (env_debugserver_path, false);
1139 log->Printf ("GDBRemoteCommunication::%s() gdb-remote stub exe path set from environment variable: %s", __FUNCTION__, env_debugserver_path);
1142 debugserver_file_spec = g_debugserver_file_spec;
1143 bool debugserver_exists = debugserver_file_spec.Exists();
1144 if (!debugserver_exists)
1146 // The debugserver binary is in the LLDB.framework/Resources
1148 if (HostInfo::GetLLDBPath(ePathTypeSupportExecutableDir, debugserver_file_spec))
1150 debugserver_file_spec.AppendPathComponent (DEBUGSERVER_BASENAME);
1151 debugserver_exists = debugserver_file_spec.Exists();
1152 if (debugserver_exists)
1155 log->Printf ("GDBRemoteCommunication::%s() found gdb-remote stub exe '%s'", __FUNCTION__, debugserver_file_spec.GetPath ().c_str ());
1157 g_debugserver_file_spec = debugserver_file_spec;
1161 debugserver_file_spec = platform->LocateExecutable(DEBUGSERVER_BASENAME);
1162 if (debugserver_file_spec)
1164 // Platform::LocateExecutable() wouldn't return a path if it doesn't exist
1165 debugserver_exists = true;
1170 log->Printf ("GDBRemoteCommunication::%s() could not find gdb-remote stub exe '%s'", __FUNCTION__, debugserver_file_spec.GetPath ().c_str ());
1172 // Don't cache the platform specific GDB server binary as it could change
1173 // from platform to platform
1174 g_debugserver_file_spec.Clear();
1179 if (debugserver_exists)
1181 debugserver_file_spec.GetPath (debugserver_path, sizeof(debugserver_path));
1183 Args &debugserver_args = launch_info.GetArguments();
1184 debugserver_args.Clear();
1185 char arg_cstr[PATH_MAX];
1187 // Start args with "debugserver /file/path -r --"
1188 debugserver_args.AppendArgument(debugserver_path);
1190 #if !defined(__APPLE__)
1191 // First argument to lldb-server must be mode in which to run.
1192 debugserver_args.AppendArgument("gdbserver");
1195 // If a url is supplied then use it
1197 debugserver_args.AppendArgument(url);
1199 // use native registers, not the GDB registers
1200 debugserver_args.AppendArgument("--native-regs");
1202 if (launch_info.GetLaunchInSeparateProcessGroup())
1204 debugserver_args.AppendArgument("--setsid");
1207 llvm::SmallString<PATH_MAX> named_pipe_path;
1208 // socket_pipe is used by debug server to communicate back either
1209 // TCP port or domain socket name which it listens on.
1210 // The second purpose of the pipe to serve as a synchronization point -
1211 // once data is written to the pipe, debug server is up and running.
1214 // port is null when debug server should listen on domain socket -
1215 // we're not interested in port value but rather waiting for debug server
1216 // to become available.
1217 if ((port != nullptr && *port == 0) || port == nullptr)
1221 // Create a temporary file to get the stdout/stderr and redirect the
1222 // output of the command into this file. We will later read this file
1223 // if all goes well and fill the data into "command_output_ptr"
1225 #if defined(__APPLE__)
1226 // Binding to port zero, we need to figure out what port it ends up
1227 // using using a named pipe...
1228 error = socket_pipe.CreateWithUniqueName("debugserver-named-pipe", false, named_pipe_path);
1232 log->Printf("GDBRemoteCommunication::%s() "
1233 "named pipe creation failed: %s",
1234 __FUNCTION__, error.AsCString());
1237 debugserver_args.AppendArgument("--named-pipe");
1238 debugserver_args.AppendArgument(named_pipe_path.c_str());
1240 // Binding to port zero, we need to figure out what port it ends up
1241 // using using an unnamed pipe...
1242 error = socket_pipe.CreateNew(true);
1246 log->Printf("GDBRemoteCommunication::%s() "
1247 "unnamed pipe creation failed: %s",
1248 __FUNCTION__, error.AsCString());
1251 int write_fd = socket_pipe.GetWriteFileDescriptor();
1252 debugserver_args.AppendArgument("--pipe");
1253 debugserver_args.AppendArgument(std::to_string(write_fd).c_str());
1254 launch_info.AppendCloseFileAction(socket_pipe.GetReadFileDescriptor());
1259 // No host and port given, so lets listen on our end and make the debugserver
1261 error = StartListenThread ("127.0.0.1", 0);
1265 log->Printf ("GDBRemoteCommunication::%s() unable to start listen thread: %s", __FUNCTION__, error.AsCString());
1269 ConnectionFileDescriptor *connection = (ConnectionFileDescriptor *)GetConnection ();
1270 // Wait for 10 seconds to resolve the bound port
1271 *port = connection->GetListeningPort(10);
1275 snprintf(port_cstr, sizeof(port_cstr), "127.0.0.1:%i", *port);
1276 // Send the host and port down that debugserver and specify an option
1277 // so that it connects back to the port we are listening to in this process
1278 debugserver_args.AppendArgument("--reverse-connect");
1279 debugserver_args.AppendArgument(port_cstr);
1283 error.SetErrorString ("failed to bind to port 0 on 127.0.0.1");
1285 log->Printf ("GDBRemoteCommunication::%s() failed: %s", __FUNCTION__, error.AsCString());
1291 const char *env_debugserver_log_file = getenv("LLDB_DEBUGSERVER_LOG_FILE");
1292 if (env_debugserver_log_file)
1294 ::snprintf (arg_cstr, sizeof(arg_cstr), "--log-file=%s", env_debugserver_log_file);
1295 debugserver_args.AppendArgument(arg_cstr);
1298 #if defined(__APPLE__)
1299 const char *env_debugserver_log_flags = getenv("LLDB_DEBUGSERVER_LOG_FLAGS");
1300 if (env_debugserver_log_flags)
1302 ::snprintf (arg_cstr, sizeof(arg_cstr), "--log-flags=%s", env_debugserver_log_flags);
1303 debugserver_args.AppendArgument(arg_cstr);
1306 const char *env_debugserver_log_channels = getenv("LLDB_SERVER_LOG_CHANNELS");
1307 if (env_debugserver_log_channels)
1309 ::snprintf (arg_cstr, sizeof(arg_cstr), "--log-channels=%s", env_debugserver_log_channels);
1310 debugserver_args.AppendArgument(arg_cstr);
1314 // Add additional args, starting with LLDB_DEBUGSERVER_EXTRA_ARG_1 until an env var doesn't come back.
1315 uint32_t env_var_index = 1;
1319 char env_var_name[64];
1320 snprintf (env_var_name, sizeof (env_var_name), "LLDB_DEBUGSERVER_EXTRA_ARG_%" PRIu32, env_var_index++);
1321 const char *extra_arg = getenv(env_var_name);
1322 has_env_var = extra_arg != nullptr;
1326 debugserver_args.AppendArgument (extra_arg);
1328 log->Printf ("GDBRemoteCommunication::%s adding env var %s contents to stub command line (%s)", __FUNCTION__, env_var_name, extra_arg);
1330 } while (has_env_var);
1332 if (inferior_args.GetArgumentCount() > 0)
1334 debugserver_args.AppendArgument ("--");
1335 debugserver_args.AppendArguments (inferior_args);
1338 // Copy the current environment to the gdbserver/debugserver instance
1340 if (Host::GetEnvironment(env))
1342 for (size_t i = 0; i < env.GetSize(); ++i)
1343 launch_info.GetEnvironmentEntries().AppendArgument(env[i].c_str());
1346 // Close STDIN, STDOUT and STDERR.
1347 launch_info.AppendCloseFileAction (STDIN_FILENO);
1348 launch_info.AppendCloseFileAction (STDOUT_FILENO);
1349 launch_info.AppendCloseFileAction (STDERR_FILENO);
1351 // Redirect STDIN, STDOUT and STDERR to "/dev/null".
1352 launch_info.AppendSuppressFileAction (STDIN_FILENO, true, false);
1353 launch_info.AppendSuppressFileAction (STDOUT_FILENO, false, true);
1354 launch_info.AppendSuppressFileAction (STDERR_FILENO, false, true);
1356 error = Host::LaunchProcess(launch_info);
1358 if (error.Success() &&
1359 launch_info.GetProcessID() != LLDB_INVALID_PROCESS_ID)
1361 if (named_pipe_path.size() > 0)
1363 error = socket_pipe.OpenAsReader(named_pipe_path, false);
1366 log->Printf("GDBRemoteCommunication::%s() "
1367 "failed to open named pipe %s for reading: %s",
1368 __FUNCTION__, named_pipe_path.c_str(), error.AsCString());
1371 if (socket_pipe.CanWrite())
1372 socket_pipe.CloseWriteFileDescriptor();
1373 if (socket_pipe.CanRead())
1375 char port_cstr[PATH_MAX] = {0};
1376 port_cstr[0] = '\0';
1377 size_t num_bytes = sizeof(port_cstr);
1378 // Read port from pipe with 10 second timeout.
1379 error = socket_pipe.ReadWithTimeout(port_cstr, num_bytes,
1380 std::chrono::seconds{10}, num_bytes);
1381 if (error.Success() && (port != nullptr))
1383 assert(num_bytes > 0 && port_cstr[num_bytes-1] == '\0');
1384 *port = StringConvert::ToUInt32(port_cstr, 0);
1386 log->Printf("GDBRemoteCommunication::%s() "
1387 "debugserver listens %u port",
1388 __FUNCTION__, *port);
1393 log->Printf("GDBRemoteCommunication::%s() "
1394 "failed to read a port value from pipe %s: %s",
1395 __FUNCTION__, named_pipe_path.c_str(), error.AsCString());
1398 socket_pipe.Close();
1401 if (named_pipe_path.size() > 0)
1403 const auto err = socket_pipe.Delete(named_pipe_path);
1407 log->Printf ("GDBRemoteCommunication::%s failed to delete pipe %s: %s",
1408 __FUNCTION__, named_pipe_path.c_str(), err.AsCString());
1412 // Make sure we actually connect with the debugserver...
1418 error.SetErrorStringWithFormat ("unable to locate " DEBUGSERVER_BASENAME );
1424 log->Printf ("GDBRemoteCommunication::%s() failed: %s", __FUNCTION__, error.AsCString());
1431 GDBRemoteCommunication::DumpHistory(Stream &strm)
1433 m_history.Dump (strm);
1436 GDBRemoteCommunication::ScopedTimeout::ScopedTimeout (GDBRemoteCommunication& gdb_comm,
1438 m_gdb_comm (gdb_comm)
1440 m_saved_timeout = m_gdb_comm.SetPacketTimeout (timeout);
1443 GDBRemoteCommunication::ScopedTimeout::~ScopedTimeout ()
1445 m_gdb_comm.SetPacketTimeout (m_saved_timeout);
1448 // This function is called via the Communications class read thread when bytes become available
1449 // for this connection. This function will consume all incoming bytes and try to parse whole
1450 // packets as they become available. Full packets are placed in a queue, so that all packet
1451 // requests can simply pop from this queue. Async notification packets will be dispatched
1452 // immediately to the ProcessGDBRemote Async thread via an event.
1453 void GDBRemoteCommunication::AppendBytesToCache (const uint8_t * bytes, size_t len, bool broadcast, lldb::ConnectionStatus status)
1455 StringExtractorGDBRemote packet;
1459 PacketType type = CheckForPacket(bytes, len, packet);
1461 // scrub the data so we do not pass it back to CheckForPacket
1462 // on future passes of the loop
1466 // we may have received no packet so lets bail out
1467 if (type == PacketType::Invalid)
1470 if (type == PacketType::Standard)
1472 // scope for the mutex
1474 // lock down the packet queue
1475 Mutex::Locker locker(m_packet_queue_mutex);
1476 // push a new packet into the queue
1477 m_packet_queue.push(packet);
1478 // Signal condition variable that we have a packet
1479 m_condition_queue_not_empty.Signal();
1484 if (type == PacketType::Notify)
1486 // put this packet into an event
1487 const char *pdata = packet.GetStringRef().c_str();
1489 // as the communication class, we are a broadcaster and the
1490 // async thread is tuned to listen to us
1492 eBroadcastBitGdbReadThreadGotNotify,
1493 new EventDataBytes(pdata));