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 #include <limits.h> 15 #include <string.h> 16 #include <sys/stat.h> 17 18 // C++ Includes 19 // Other libraries and framework includes 20 #include "lldb/Core/Log.h" 21 #include "lldb/Core/StreamFile.h" 22 #include "lldb/Core/StreamString.h" 23 #include "lldb/Host/ConnectionFileDescriptor.h" 24 #include "lldb/Host/FileSpec.h" 25 #include "lldb/Host/Host.h" 26 #include "lldb/Host/HostInfo.h" 27 #include "lldb/Host/Pipe.h" 28 #include "lldb/Host/Socket.h" 29 #include "lldb/Host/StringConvert.h" 30 #include "lldb/Host/ThreadLauncher.h" 31 #include "lldb/Host/TimeValue.h" 32 #include "lldb/Target/Process.h" 33 #include "llvm/ADT/SmallString.h" 34 35 // Project includes 36 #include "ProcessGDBRemoteLog.h" 37 38 #if defined(__APPLE__) 39 # define DEBUGSERVER_BASENAME "debugserver" 40 #else 41 # define DEBUGSERVER_BASENAME "lldb-server" 42 #endif 43 44 using namespace lldb; 45 using namespace lldb_private; 46 using namespace lldb_private::process_gdb_remote; 47 48 GDBRemoteCommunication::History::History (uint32_t size) : 49 m_packets(), 50 m_curr_idx (0), 51 m_total_packet_count (0), 52 m_dumped_to_log (false) 53 { 54 m_packets.resize(size); 55 } 56 57 GDBRemoteCommunication::History::~History () 58 { 59 } 60 61 void 62 GDBRemoteCommunication::History::AddPacket (char packet_char, 63 PacketType type, 64 uint32_t bytes_transmitted) 65 { 66 const size_t size = m_packets.size(); 67 if (size > 0) 68 { 69 const uint32_t idx = GetNextIndex(); 70 m_packets[idx].packet.assign (1, packet_char); 71 m_packets[idx].type = type; 72 m_packets[idx].bytes_transmitted = bytes_transmitted; 73 m_packets[idx].packet_idx = m_total_packet_count; 74 m_packets[idx].tid = Host::GetCurrentThreadID(); 75 } 76 } 77 78 void 79 GDBRemoteCommunication::History::AddPacket (const std::string &src, 80 uint32_t src_len, 81 PacketType type, 82 uint32_t bytes_transmitted) 83 { 84 const size_t size = m_packets.size(); 85 if (size > 0) 86 { 87 const uint32_t idx = GetNextIndex(); 88 m_packets[idx].packet.assign (src, 0, src_len); 89 m_packets[idx].type = type; 90 m_packets[idx].bytes_transmitted = bytes_transmitted; 91 m_packets[idx].packet_idx = m_total_packet_count; 92 m_packets[idx].tid = Host::GetCurrentThreadID(); 93 } 94 } 95 96 void 97 GDBRemoteCommunication::History::Dump (Stream &strm) const 98 { 99 const uint32_t size = GetNumPacketsInHistory (); 100 const uint32_t first_idx = GetFirstSavedPacketIndex (); 101 const uint32_t stop_idx = m_curr_idx + size; 102 for (uint32_t i = first_idx; i < stop_idx; ++i) 103 { 104 const uint32_t idx = NormalizeIndex (i); 105 const Entry &entry = m_packets[idx]; 106 if (entry.type == ePacketTypeInvalid || entry.packet.empty()) 107 break; 108 strm.Printf ("history[%u] tid=0x%4.4" PRIx64 " <%4u> %s packet: %s\n", 109 entry.packet_idx, 110 entry.tid, 111 entry.bytes_transmitted, 112 (entry.type == ePacketTypeSend) ? "send" : "read", 113 entry.packet.c_str()); 114 } 115 } 116 117 void 118 GDBRemoteCommunication::History::Dump (Log *log) const 119 { 120 if (log && !m_dumped_to_log) 121 { 122 m_dumped_to_log = true; 123 const uint32_t size = GetNumPacketsInHistory (); 124 const uint32_t first_idx = GetFirstSavedPacketIndex (); 125 const uint32_t stop_idx = m_curr_idx + size; 126 for (uint32_t i = first_idx; i < stop_idx; ++i) 127 { 128 const uint32_t idx = NormalizeIndex (i); 129 const Entry &entry = m_packets[idx]; 130 if (entry.type == ePacketTypeInvalid || entry.packet.empty()) 131 break; 132 log->Printf ("history[%u] tid=0x%4.4" PRIx64 " <%4u> %s packet: %s", 133 entry.packet_idx, 134 entry.tid, 135 entry.bytes_transmitted, 136 (entry.type == ePacketTypeSend) ? "send" : "read", 137 entry.packet.c_str()); 138 } 139 } 140 } 141 142 //---------------------------------------------------------------------- 143 // GDBRemoteCommunication constructor 144 //---------------------------------------------------------------------- 145 GDBRemoteCommunication::GDBRemoteCommunication(const char *comm_name, 146 const char *listener_name) : 147 Communication(comm_name), 148 #ifdef LLDB_CONFIGURATION_DEBUG 149 m_packet_timeout (1000), 150 #else 151 m_packet_timeout (1), 152 #endif 153 m_sequence_mutex (Mutex::eMutexTypeRecursive), 154 m_public_is_running (false), 155 m_private_is_running (false), 156 m_history (512), 157 m_send_acks (true), 158 m_listen_url () 159 { 160 } 161 162 //---------------------------------------------------------------------- 163 // Destructor 164 //---------------------------------------------------------------------- 165 GDBRemoteCommunication::~GDBRemoteCommunication() 166 { 167 if (IsConnected()) 168 { 169 Disconnect(); 170 } 171 } 172 173 char 174 GDBRemoteCommunication::CalculcateChecksum (const char *payload, size_t payload_length) 175 { 176 int checksum = 0; 177 178 for (size_t i = 0; i < payload_length; ++i) 179 checksum += payload[i]; 180 181 return checksum & 255; 182 } 183 184 size_t 185 GDBRemoteCommunication::SendAck () 186 { 187 Log *log (ProcessGDBRemoteLog::GetLogIfAllCategoriesSet (GDBR_LOG_PACKETS)); 188 ConnectionStatus status = eConnectionStatusSuccess; 189 char ch = '+'; 190 const size_t bytes_written = Write (&ch, 1, status, NULL); 191 if (log) 192 log->Printf ("<%4" PRIu64 "> send packet: %c", (uint64_t)bytes_written, ch); 193 m_history.AddPacket (ch, History::ePacketTypeSend, bytes_written); 194 return bytes_written; 195 } 196 197 size_t 198 GDBRemoteCommunication::SendNack () 199 { 200 Log *log (ProcessGDBRemoteLog::GetLogIfAllCategoriesSet (GDBR_LOG_PACKETS)); 201 ConnectionStatus status = eConnectionStatusSuccess; 202 char ch = '-'; 203 const size_t bytes_written = Write (&ch, 1, status, NULL); 204 if (log) 205 log->Printf("<%4" PRIu64 "> send packet: %c", (uint64_t)bytes_written, ch); 206 m_history.AddPacket (ch, History::ePacketTypeSend, bytes_written); 207 return bytes_written; 208 } 209 210 GDBRemoteCommunication::PacketResult 211 GDBRemoteCommunication::SendPacket (const char *payload, size_t payload_length) 212 { 213 Mutex::Locker locker(m_sequence_mutex); 214 return SendPacketNoLock (payload, payload_length); 215 } 216 217 GDBRemoteCommunication::PacketResult 218 GDBRemoteCommunication::SendPacketNoLock (const char *payload, size_t payload_length) 219 { 220 if (IsConnected()) 221 { 222 StreamString packet(0, 4, eByteOrderBig); 223 224 packet.PutChar('$'); 225 packet.Write (payload, payload_length); 226 packet.PutChar('#'); 227 packet.PutHex8(CalculcateChecksum (payload, payload_length)); 228 229 Log *log (ProcessGDBRemoteLog::GetLogIfAllCategoriesSet (GDBR_LOG_PACKETS)); 230 ConnectionStatus status = eConnectionStatusSuccess; 231 const char *packet_data = packet.GetData(); 232 const size_t packet_length = packet.GetSize(); 233 size_t bytes_written = Write (packet_data, packet_length, status, NULL); 234 if (log) 235 { 236 size_t binary_start_offset = 0; 237 if (strncmp(packet_data, "$vFile:pwrite:", strlen("$vFile:pwrite:")) == 0) 238 { 239 const char *first_comma = strchr(packet_data, ','); 240 if (first_comma) 241 { 242 const char *second_comma = strchr(first_comma + 1, ','); 243 if (second_comma) 244 binary_start_offset = second_comma - packet_data + 1; 245 } 246 } 247 248 // If logging was just enabled and we have history, then dump out what 249 // we have to the log so we get the historical context. The Dump() call that 250 // logs all of the packet will set a boolean so that we don't dump this more 251 // than once 252 if (!m_history.DidDumpToLog ()) 253 m_history.Dump (log); 254 255 if (binary_start_offset) 256 { 257 StreamString strm; 258 // Print non binary data header 259 strm.Printf("<%4" PRIu64 "> send packet: %.*s", (uint64_t)bytes_written, (int)binary_start_offset, packet_data); 260 const uint8_t *p; 261 // Print binary data exactly as sent 262 for (p = (const uint8_t*)packet_data + binary_start_offset; *p != '#'; ++p) 263 strm.Printf("\\x%2.2x", *p); 264 // Print the checksum 265 strm.Printf("%*s", (int)3, p); 266 log->PutCString(strm.GetString().c_str()); 267 } 268 else 269 log->Printf("<%4" PRIu64 "> send packet: %.*s", (uint64_t)bytes_written, (int)packet_length, packet_data); 270 } 271 272 m_history.AddPacket (packet.GetString(), packet_length, History::ePacketTypeSend, bytes_written); 273 274 275 if (bytes_written == packet_length) 276 { 277 if (GetSendAcks ()) 278 return GetAck (); 279 else 280 return PacketResult::Success; 281 } 282 else 283 { 284 if (log) 285 log->Printf ("error: failed to send packet: %.*s", (int)packet_length, packet_data); 286 } 287 } 288 return PacketResult::ErrorSendFailed; 289 } 290 291 GDBRemoteCommunication::PacketResult 292 GDBRemoteCommunication::GetAck () 293 { 294 StringExtractorGDBRemote packet; 295 PacketResult result = WaitForPacketWithTimeoutMicroSecondsNoLock (packet, GetPacketTimeoutInMicroSeconds ()); 296 if (result == PacketResult::Success) 297 { 298 if (packet.GetResponseType() == StringExtractorGDBRemote::ResponseType::eAck) 299 return PacketResult::Success; 300 else 301 return PacketResult::ErrorSendAck; 302 } 303 return result; 304 } 305 306 bool 307 GDBRemoteCommunication::GetSequenceMutex (Mutex::Locker& locker, const char *failure_message) 308 { 309 if (IsRunning()) 310 return locker.TryLock (m_sequence_mutex, failure_message); 311 312 locker.Lock (m_sequence_mutex); 313 return true; 314 } 315 316 317 bool 318 GDBRemoteCommunication::WaitForNotRunningPrivate (const TimeValue *timeout_ptr) 319 { 320 return m_private_is_running.WaitForValueEqualTo (false, timeout_ptr, NULL); 321 } 322 323 GDBRemoteCommunication::PacketResult 324 GDBRemoteCommunication::WaitForPacketWithTimeoutMicroSecondsNoLock (StringExtractorGDBRemote &packet, uint32_t timeout_usec) 325 { 326 uint8_t buffer[8192]; 327 Error error; 328 329 Log *log (ProcessGDBRemoteLog::GetLogIfAllCategoriesSet (GDBR_LOG_PACKETS | GDBR_LOG_VERBOSE)); 330 331 // Check for a packet from our cache first without trying any reading... 332 if (CheckForPacket(NULL, 0, packet) != PacketType::Invalid) 333 return PacketResult::Success; 334 335 bool timed_out = false; 336 bool disconnected = false; 337 while (IsConnected() && !timed_out) 338 { 339 lldb::ConnectionStatus status = eConnectionStatusNoConnection; 340 size_t bytes_read = Read (buffer, sizeof(buffer), timeout_usec, status, &error); 341 342 if (log) 343 log->Printf ("%s: Read (buffer, (sizeof(buffer), timeout_usec = 0x%x, status = %s, error = %s) => bytes_read = %" PRIu64, 344 __PRETTY_FUNCTION__, 345 timeout_usec, 346 Communication::ConnectionStatusAsCString (status), 347 error.AsCString(), 348 (uint64_t)bytes_read); 349 350 if (bytes_read > 0) 351 { 352 if (CheckForPacket(buffer, bytes_read, packet) != PacketType::Invalid) 353 return PacketResult::Success; 354 } 355 else 356 { 357 switch (status) 358 { 359 case eConnectionStatusTimedOut: 360 case eConnectionStatusInterrupted: 361 timed_out = true; 362 break; 363 case eConnectionStatusSuccess: 364 //printf ("status = success but error = %s\n", error.AsCString("<invalid>")); 365 break; 366 367 case eConnectionStatusEndOfFile: 368 case eConnectionStatusNoConnection: 369 case eConnectionStatusLostConnection: 370 case eConnectionStatusError: 371 disconnected = true; 372 Disconnect(); 373 break; 374 } 375 } 376 } 377 packet.Clear (); 378 if (disconnected) 379 return PacketResult::ErrorDisconnected; 380 if (timed_out) 381 return PacketResult::ErrorReplyTimeout; 382 else 383 return PacketResult::ErrorReplyFailed; 384 } 385 386 GDBRemoteCommunication::PacketType 387 GDBRemoteCommunication::CheckForPacket (const uint8_t *src, size_t src_len, StringExtractorGDBRemote &packet) 388 { 389 // Put the packet data into the buffer in a thread safe fashion 390 Mutex::Locker locker(m_bytes_mutex); 391 392 Log *log (ProcessGDBRemoteLog::GetLogIfAllCategoriesSet (GDBR_LOG_PACKETS)); 393 394 if (src && src_len > 0) 395 { 396 if (log && log->GetVerbose()) 397 { 398 StreamString s; 399 log->Printf ("GDBRemoteCommunication::%s adding %u bytes: %.*s", 400 __FUNCTION__, 401 (uint32_t)src_len, 402 (uint32_t)src_len, 403 src); 404 } 405 m_bytes.append ((const char *)src, src_len); 406 } 407 408 bool isNotifyPacket = false; 409 410 // Parse up the packets into gdb remote packets 411 if (!m_bytes.empty()) 412 { 413 // end_idx must be one past the last valid packet byte. Start 414 // it off with an invalid value that is the same as the current 415 // index. 416 size_t content_start = 0; 417 size_t content_length = 0; 418 size_t total_length = 0; 419 size_t checksum_idx = std::string::npos; 420 421 switch (m_bytes[0]) 422 { 423 case '+': // Look for ack 424 case '-': // Look for cancel 425 case '\x03': // ^C to halt target 426 content_length = total_length = 1; // The command is one byte long... 427 break; 428 429 case '%': // Async notify packet 430 isNotifyPacket = true; 431 // Intentional fall through 432 433 case '$': 434 // Look for a standard gdb packet? 435 { 436 size_t hash_pos = m_bytes.find('#'); 437 if (hash_pos != std::string::npos) 438 { 439 if (hash_pos + 2 < m_bytes.size()) 440 { 441 checksum_idx = hash_pos + 1; 442 // Skip the dollar sign 443 content_start = 1; 444 // Don't include the # in the content or the $ in the content length 445 content_length = hash_pos - 1; 446 447 total_length = hash_pos + 3; // Skip the # and the two hex checksum bytes 448 } 449 else 450 { 451 // Checksum bytes aren't all here yet 452 content_length = std::string::npos; 453 } 454 } 455 } 456 break; 457 458 default: 459 { 460 // We have an unexpected byte and we need to flush all bad 461 // data that is in m_bytes, so we need to find the first 462 // byte that is a '+' (ACK), '-' (NACK), \x03 (CTRL+C interrupt), 463 // or '$' character (start of packet header) or of course, 464 // the end of the data in m_bytes... 465 const size_t bytes_len = m_bytes.size(); 466 bool done = false; 467 uint32_t idx; 468 for (idx = 1; !done && idx < bytes_len; ++idx) 469 { 470 switch (m_bytes[idx]) 471 { 472 case '+': 473 case '-': 474 case '\x03': 475 case '%': 476 case '$': 477 done = true; 478 break; 479 480 default: 481 break; 482 } 483 } 484 if (log) 485 log->Printf ("GDBRemoteCommunication::%s tossing %u junk bytes: '%.*s'", 486 __FUNCTION__, idx - 1, idx - 1, m_bytes.c_str()); 487 m_bytes.erase(0, idx - 1); 488 } 489 break; 490 } 491 492 if (content_length == std::string::npos) 493 { 494 packet.Clear(); 495 return GDBRemoteCommunication::PacketType::Invalid; 496 } 497 else if (total_length > 0) 498 { 499 500 // We have a valid packet... 501 assert (content_length <= m_bytes.size()); 502 assert (total_length <= m_bytes.size()); 503 assert (content_length <= total_length); 504 const size_t content_end = content_start + content_length; 505 506 bool success = true; 507 std::string &packet_str = packet.GetStringRef(); 508 509 510 if (log) 511 { 512 // If logging was just enabled and we have history, then dump out what 513 // we have to the log so we get the historical context. The Dump() call that 514 // logs all of the packet will set a boolean so that we don't dump this more 515 // than once 516 if (!m_history.DidDumpToLog ()) 517 m_history.Dump (log); 518 519 bool binary = false; 520 // Only detect binary for packets that start with a '$' and have a '#CC' checksum 521 if (m_bytes[0] == '$' && total_length > 4) 522 { 523 for (size_t i=0; !binary && i<total_length; ++i) 524 { 525 if (isprint(m_bytes[i]) == 0) 526 binary = true; 527 } 528 } 529 if (binary) 530 { 531 StreamString strm; 532 // Packet header... 533 strm.Printf("<%4" PRIu64 "> read packet: %c", (uint64_t)total_length, m_bytes[0]); 534 for (size_t i=content_start; i<content_end; ++i) 535 { 536 // Remove binary escaped bytes when displaying the packet... 537 const char ch = m_bytes[i]; 538 if (ch == 0x7d) 539 { 540 // 0x7d is the escape character. The next character is to 541 // be XOR'd with 0x20. 542 const char escapee = m_bytes[++i] ^ 0x20; 543 strm.Printf("%2.2x", escapee); 544 } 545 else 546 { 547 strm.Printf("%2.2x", (uint8_t)ch); 548 } 549 } 550 // Packet footer... 551 strm.Printf("%c%c%c", m_bytes[total_length-3], m_bytes[total_length-2], m_bytes[total_length-1]); 552 log->PutCString(strm.GetString().c_str()); 553 } 554 else 555 { 556 log->Printf("<%4" PRIu64 "> read packet: %.*s", (uint64_t)total_length, (int)(total_length), m_bytes.c_str()); 557 } 558 } 559 560 m_history.AddPacket (m_bytes.c_str(), total_length, History::ePacketTypeRecv, total_length); 561 562 // Clear packet_str in case there is some existing data in it. 563 packet_str.clear(); 564 // Copy the packet from m_bytes to packet_str expanding the 565 // run-length encoding in the process. 566 // Reserve enough byte for the most common case (no RLE used) 567 packet_str.reserve(m_bytes.length()); 568 for (std::string::const_iterator c = m_bytes.begin() + content_start; c != m_bytes.begin() + content_end; ++c) 569 { 570 if (*c == '*') 571 { 572 // '*' indicates RLE. Next character will give us the 573 // repeat count and previous character is what is to be 574 // repeated. 575 char char_to_repeat = packet_str.back(); 576 // Number of time the previous character is repeated 577 int repeat_count = *++c + 3 - ' '; 578 // We have the char_to_repeat and repeat_count. Now push 579 // it in the packet. 580 for (int i = 0; i < repeat_count; ++i) 581 packet_str.push_back(char_to_repeat); 582 } 583 else if (*c == 0x7d) 584 { 585 // 0x7d is the escape character. The next character is to 586 // be XOR'd with 0x20. 587 char escapee = *++c ^ 0x20; 588 packet_str.push_back(escapee); 589 } 590 else 591 { 592 packet_str.push_back(*c); 593 } 594 } 595 596 if (m_bytes[0] == '$' || m_bytes[0] == '%') 597 { 598 assert (checksum_idx < m_bytes.size()); 599 if (::isxdigit (m_bytes[checksum_idx+0]) || 600 ::isxdigit (m_bytes[checksum_idx+1])) 601 { 602 if (GetSendAcks ()) 603 { 604 const char *packet_checksum_cstr = &m_bytes[checksum_idx]; 605 char packet_checksum = strtol (packet_checksum_cstr, NULL, 16); 606 char actual_checksum = CalculcateChecksum (packet_str.c_str(), packet_str.size()); 607 success = packet_checksum == actual_checksum; 608 if (!success) 609 { 610 if (log) 611 log->Printf ("error: checksum mismatch: %.*s expected 0x%2.2x, got 0x%2.2x", 612 (int)(total_length), 613 m_bytes.c_str(), 614 (uint8_t)packet_checksum, 615 (uint8_t)actual_checksum); 616 } 617 // Send the ack or nack if needed 618 if (!success) 619 SendNack(); 620 else 621 SendAck(); 622 } 623 } 624 else 625 { 626 success = false; 627 if (log) 628 log->Printf ("error: invalid checksum in packet: '%s'\n", m_bytes.c_str()); 629 } 630 } 631 632 m_bytes.erase(0, total_length); 633 packet.SetFilePos(0); 634 635 if (isNotifyPacket) 636 return GDBRemoteCommunication::PacketType::Notify; 637 else 638 return GDBRemoteCommunication::PacketType::Standard; 639 } 640 } 641 packet.Clear(); 642 return GDBRemoteCommunication::PacketType::Invalid; 643 } 644 645 Error 646 GDBRemoteCommunication::StartListenThread (const char *hostname, uint16_t port) 647 { 648 Error error; 649 if (m_listen_thread.IsJoinable()) 650 { 651 error.SetErrorString("listen thread already running"); 652 } 653 else 654 { 655 char listen_url[512]; 656 if (hostname && hostname[0]) 657 snprintf(listen_url, sizeof(listen_url), "listen://%s:%i", hostname, port); 658 else 659 snprintf(listen_url, sizeof(listen_url), "listen://%i", port); 660 m_listen_url = listen_url; 661 SetConnection(new ConnectionFileDescriptor()); 662 m_listen_thread = ThreadLauncher::LaunchThread(listen_url, GDBRemoteCommunication::ListenThread, this, &error); 663 } 664 return error; 665 } 666 667 bool 668 GDBRemoteCommunication::JoinListenThread () 669 { 670 if (m_listen_thread.IsJoinable()) 671 m_listen_thread.Join(nullptr); 672 return true; 673 } 674 675 lldb::thread_result_t 676 GDBRemoteCommunication::ListenThread (lldb::thread_arg_t arg) 677 { 678 GDBRemoteCommunication *comm = (GDBRemoteCommunication *)arg; 679 Error error; 680 ConnectionFileDescriptor *connection = (ConnectionFileDescriptor *)comm->GetConnection (); 681 682 if (connection) 683 { 684 // Do the listen on another thread so we can continue on... 685 if (connection->Connect(comm->m_listen_url.c_str(), &error) != eConnectionStatusSuccess) 686 comm->SetConnection(NULL); 687 } 688 return NULL; 689 } 690 691 Error 692 GDBRemoteCommunication::StartDebugserverProcess (const char *hostname, 693 uint16_t in_port, 694 ProcessLaunchInfo &launch_info, 695 uint16_t &out_port) 696 { 697 Log *log (ProcessGDBRemoteLog::GetLogIfAllCategoriesSet (GDBR_LOG_PROCESS)); 698 if (log) 699 log->Printf ("GDBRemoteCommunication::%s(hostname=%s, in_port=%" PRIu16 ", out_port=%" PRIu16, __FUNCTION__, hostname ? hostname : "<empty>", in_port, out_port); 700 701 out_port = in_port; 702 Error error; 703 // If we locate debugserver, keep that located version around 704 static FileSpec g_debugserver_file_spec; 705 706 char debugserver_path[PATH_MAX]; 707 FileSpec &debugserver_file_spec = launch_info.GetExecutableFile(); 708 709 // Always check to see if we have an environment override for the path 710 // to the debugserver to use and use it if we do. 711 const char *env_debugserver_path = getenv("LLDB_DEBUGSERVER_PATH"); 712 if (env_debugserver_path) 713 { 714 debugserver_file_spec.SetFile (env_debugserver_path, false); 715 if (log) 716 log->Printf ("GDBRemoteCommunication::%s() gdb-remote stub exe path set from environment variable: %s", __FUNCTION__, env_debugserver_path); 717 } 718 else 719 debugserver_file_spec = g_debugserver_file_spec; 720 bool debugserver_exists = debugserver_file_spec.Exists(); 721 if (!debugserver_exists) 722 { 723 // The debugserver binary is in the LLDB.framework/Resources 724 // directory. 725 if (HostInfo::GetLLDBPath(ePathTypeSupportExecutableDir, debugserver_file_spec)) 726 { 727 debugserver_file_spec.AppendPathComponent (DEBUGSERVER_BASENAME); 728 debugserver_exists = debugserver_file_spec.Exists(); 729 if (debugserver_exists) 730 { 731 if (log) 732 log->Printf ("GDBRemoteCommunication::%s() found gdb-remote stub exe '%s'", __FUNCTION__, debugserver_file_spec.GetPath ().c_str ()); 733 734 g_debugserver_file_spec = debugserver_file_spec; 735 } 736 else 737 { 738 if (log) 739 log->Printf ("GDBRemoteCommunication::%s() could not find gdb-remote stub exe '%s'", __FUNCTION__, debugserver_file_spec.GetPath ().c_str ()); 740 741 g_debugserver_file_spec.Clear(); 742 debugserver_file_spec.Clear(); 743 } 744 } 745 } 746 747 if (debugserver_exists) 748 { 749 debugserver_file_spec.GetPath (debugserver_path, sizeof(debugserver_path)); 750 751 Args &debugserver_args = launch_info.GetArguments(); 752 debugserver_args.Clear(); 753 char arg_cstr[PATH_MAX]; 754 755 // Start args with "debugserver /file/path -r --" 756 debugserver_args.AppendArgument(debugserver_path); 757 758 #if !defined(__APPLE__) 759 // First argument to lldb-server must be mode in which to run. 760 debugserver_args.AppendArgument("gdbserver"); 761 #endif 762 763 // If a host and port is supplied then use it 764 char host_and_port[128]; 765 if (hostname) 766 { 767 snprintf (host_and_port, sizeof(host_and_port), "%s:%u", hostname, in_port); 768 debugserver_args.AppendArgument(host_and_port); 769 } 770 else 771 { 772 host_and_port[0] = '\0'; 773 } 774 775 // use native registers, not the GDB registers 776 debugserver_args.AppendArgument("--native-regs"); 777 778 if (launch_info.GetLaunchInSeparateProcessGroup()) 779 { 780 debugserver_args.AppendArgument("--setsid"); 781 } 782 783 llvm::SmallString<PATH_MAX> named_pipe_path; 784 Pipe port_pipe; 785 786 if (host_and_port[0] && in_port == 0) 787 { 788 // Create a temporary file to get the stdout/stderr and redirect the 789 // output of the command into this file. We will later read this file 790 // if all goes well and fill the data into "command_output_ptr" 791 792 // Binding to port zero, we need to figure out what port it ends up 793 // using using a named pipe... 794 error = port_pipe.CreateWithUniqueName("debugserver-named-pipe", false, named_pipe_path); 795 if (error.Success()) 796 { 797 debugserver_args.AppendArgument("--named-pipe"); 798 debugserver_args.AppendArgument(named_pipe_path.c_str()); 799 } 800 else 801 { 802 if (log) 803 log->Printf("GDBRemoteCommunication::%s() " 804 "named pipe creation failed: %s", 805 __FUNCTION__, error.AsCString()); 806 // let's try an unnamed pipe 807 error = port_pipe.CreateNew(true); 808 if (error.Fail()) 809 { 810 if (log) 811 log->Printf("GDBRemoteCommunication::%s() " 812 "unnamed pipe creation failed: %s", 813 __FUNCTION__, error.AsCString()); 814 return error; 815 } 816 int write_fd = port_pipe.GetWriteFileDescriptor(); 817 debugserver_args.AppendArgument("--pipe"); 818 debugserver_args.AppendArgument(std::to_string(write_fd).c_str()); 819 launch_info.AppendCloseFileAction(port_pipe.GetReadFileDescriptor()); 820 } 821 } 822 else 823 { 824 // No host and port given, so lets listen on our end and make the debugserver 825 // connect to us.. 826 error = StartListenThread ("127.0.0.1", 0); 827 if (error.Fail()) 828 { 829 if (log) 830 log->Printf ("GDBRemoteCommunication::%s() unable to start listen thread: %s", __FUNCTION__, error.AsCString()); 831 return error; 832 } 833 834 ConnectionFileDescriptor *connection = (ConnectionFileDescriptor *)GetConnection (); 835 // Wait for 10 seconds to resolve the bound port 836 out_port = connection->GetListeningPort(10); 837 if (out_port > 0) 838 { 839 char port_cstr[32]; 840 snprintf(port_cstr, sizeof(port_cstr), "127.0.0.1:%i", out_port); 841 // Send the host and port down that debugserver and specify an option 842 // so that it connects back to the port we are listening to in this process 843 debugserver_args.AppendArgument("--reverse-connect"); 844 debugserver_args.AppendArgument(port_cstr); 845 } 846 else 847 { 848 error.SetErrorString ("failed to bind to port 0 on 127.0.0.1"); 849 if (log) 850 log->Printf ("GDBRemoteCommunication::%s() failed: %s", __FUNCTION__, error.AsCString()); 851 return error; 852 } 853 } 854 855 const char *env_debugserver_log_file = getenv("LLDB_DEBUGSERVER_LOG_FILE"); 856 if (env_debugserver_log_file) 857 { 858 ::snprintf (arg_cstr, sizeof(arg_cstr), "--log-file=%s", env_debugserver_log_file); 859 debugserver_args.AppendArgument(arg_cstr); 860 } 861 862 #if defined(__APPLE__) 863 const char *env_debugserver_log_flags = getenv("LLDB_DEBUGSERVER_LOG_FLAGS"); 864 if (env_debugserver_log_flags) 865 { 866 ::snprintf (arg_cstr, sizeof(arg_cstr), "--log-flags=%s", env_debugserver_log_flags); 867 debugserver_args.AppendArgument(arg_cstr); 868 } 869 #else 870 const char *env_debugserver_log_channels = getenv("LLDB_SERVER_LOG_CHANNELS"); 871 if (env_debugserver_log_channels) 872 { 873 ::snprintf (arg_cstr, sizeof(arg_cstr), "--log-channels=%s", env_debugserver_log_channels); 874 debugserver_args.AppendArgument(arg_cstr); 875 } 876 #endif 877 878 // Add additional args, starting with LLDB_DEBUGSERVER_EXTRA_ARG_1 until an env var doesn't come back. 879 uint32_t env_var_index = 1; 880 bool has_env_var; 881 do 882 { 883 char env_var_name[64]; 884 snprintf (env_var_name, sizeof (env_var_name), "LLDB_DEBUGSERVER_EXTRA_ARG_%" PRIu32, env_var_index++); 885 const char *extra_arg = getenv(env_var_name); 886 has_env_var = extra_arg != nullptr; 887 888 if (has_env_var) 889 { 890 debugserver_args.AppendArgument (extra_arg); 891 if (log) 892 log->Printf ("GDBRemoteCommunication::%s adding env var %s contents to stub command line (%s)", __FUNCTION__, env_var_name, extra_arg); 893 } 894 } while (has_env_var); 895 896 // Close STDIN, STDOUT and STDERR. 897 launch_info.AppendCloseFileAction (STDIN_FILENO); 898 launch_info.AppendCloseFileAction (STDOUT_FILENO); 899 launch_info.AppendCloseFileAction (STDERR_FILENO); 900 901 // Redirect STDIN, STDOUT and STDERR to "/dev/null". 902 launch_info.AppendSuppressFileAction (STDIN_FILENO, true, false); 903 launch_info.AppendSuppressFileAction (STDOUT_FILENO, false, true); 904 launch_info.AppendSuppressFileAction (STDERR_FILENO, false, true); 905 906 error = Host::LaunchProcess(launch_info); 907 908 if (error.Success() && launch_info.GetProcessID() != LLDB_INVALID_PROCESS_ID) 909 { 910 if (named_pipe_path.size() > 0) 911 { 912 error = port_pipe.OpenAsReader(named_pipe_path, false); 913 if (error.Fail()) 914 if (log) 915 log->Printf("GDBRemoteCommunication::%s() " 916 "failed to open named pipe %s for reading: %s", 917 __FUNCTION__, named_pipe_path.c_str(), error.AsCString()); 918 } 919 920 if (port_pipe.CanWrite()) 921 port_pipe.CloseWriteFileDescriptor(); 922 if (port_pipe.CanRead()) 923 { 924 char port_cstr[256]; 925 port_cstr[0] = '\0'; 926 size_t num_bytes = sizeof(port_cstr); 927 // Read port from pipe with 10 second timeout. 928 error = port_pipe.ReadWithTimeout(port_cstr, num_bytes, 929 std::chrono::seconds{10}, num_bytes); 930 if (error.Success()) 931 { 932 assert(num_bytes > 0 && port_cstr[num_bytes-1] == '\0'); 933 out_port = StringConvert::ToUInt32(port_cstr, 0); 934 if (log) 935 log->Printf("GDBRemoteCommunication::%s() " 936 "debugserver listens %u port", 937 __FUNCTION__, out_port); 938 } 939 else 940 { 941 if (log) 942 log->Printf("GDBRemoteCommunication::%s() " 943 "failed to read a port value from pipe %s: %s", 944 __FUNCTION__, named_pipe_path.c_str(), error.AsCString()); 945 946 } 947 port_pipe.Close(); 948 } 949 950 if (named_pipe_path.size() > 0) 951 { 952 const auto err = port_pipe.Delete(named_pipe_path); 953 if (err.Fail()) 954 { 955 if (log) 956 log->Printf ("GDBRemoteCommunication::%s failed to delete pipe %s: %s", 957 __FUNCTION__, named_pipe_path.c_str(), err.AsCString()); 958 } 959 } 960 961 // Make sure we actually connect with the debugserver... 962 JoinListenThread(); 963 } 964 } 965 else 966 { 967 error.SetErrorStringWithFormat ("unable to locate " DEBUGSERVER_BASENAME ); 968 } 969 970 if (error.Fail()) 971 { 972 if (log) 973 log->Printf ("GDBRemoteCommunication::%s() failed: %s", __FUNCTION__, error.AsCString()); 974 } 975 976 return error; 977 } 978 979 void 980 GDBRemoteCommunication::DumpHistory(Stream &strm) 981 { 982 m_history.Dump (strm); 983 } 984 985 GDBRemoteCommunication::ScopedTimeout::ScopedTimeout (GDBRemoteCommunication& gdb_comm, 986 uint32_t timeout) : 987 m_gdb_comm (gdb_comm) 988 { 989 m_saved_timeout = m_gdb_comm.SetPacketTimeout (timeout); 990 } 991 992 GDBRemoteCommunication::ScopedTimeout::~ScopedTimeout () 993 { 994 m_gdb_comm.SetPacketTimeout (m_saved_timeout); 995 } 996