1 //===-- GDBRemoteCommunication.cpp ----------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #include "GDBRemoteCommunication.h" 10 11 #include <climits> 12 #include <cstring> 13 #include <future> 14 #include <sys/stat.h> 15 16 #include "lldb/Host/Config.h" 17 #include "lldb/Host/ConnectionFileDescriptor.h" 18 #include "lldb/Host/FileSystem.h" 19 #include "lldb/Host/Host.h" 20 #include "lldb/Host/HostInfo.h" 21 #include "lldb/Host/Pipe.h" 22 #include "lldb/Host/ProcessLaunchInfo.h" 23 #include "lldb/Host/Socket.h" 24 #include "lldb/Host/ThreadLauncher.h" 25 #include "lldb/Host/common/TCPSocket.h" 26 #include "lldb/Host/posix/ConnectionFileDescriptorPosix.h" 27 #include "lldb/Target/Platform.h" 28 #include "lldb/Utility/Event.h" 29 #include "lldb/Utility/FileSpec.h" 30 #include "lldb/Utility/Log.h" 31 #include "lldb/Utility/RegularExpression.h" 32 #include "lldb/Utility/StreamString.h" 33 #include "llvm/ADT/SmallString.h" 34 #include "llvm/Config/llvm-config.h" // for LLVM_ENABLE_ZLIB 35 #include "llvm/Support/ScopedPrinter.h" 36 37 #include "ProcessGDBRemoteLog.h" 38 39 #if defined(__APPLE__) 40 #define DEBUGSERVER_BASENAME "debugserver" 41 #elif defined(_WIN32) 42 #define DEBUGSERVER_BASENAME "lldb-server.exe" 43 #else 44 #define DEBUGSERVER_BASENAME "lldb-server" 45 #endif 46 47 #if defined(HAVE_LIBCOMPRESSION) 48 #include <compression.h> 49 #endif 50 51 #if LLVM_ENABLE_ZLIB 52 #include <zlib.h> 53 #endif 54 55 using namespace lldb; 56 using namespace lldb_private; 57 using namespace lldb_private::process_gdb_remote; 58 59 // GDBRemoteCommunication constructor 60 GDBRemoteCommunication::GDBRemoteCommunication() 61 : Communication(), 62 #ifdef LLDB_CONFIGURATION_DEBUG 63 m_packet_timeout(1000), 64 #else 65 m_packet_timeout(1), 66 #endif 67 m_echo_number(0), m_supports_qEcho(eLazyBoolCalculate), m_history(512), 68 m_send_acks(true), m_is_platform(false), 69 m_compression_type(CompressionType::None), m_listen_url() { 70 } 71 72 // Destructor 73 GDBRemoteCommunication::~GDBRemoteCommunication() { 74 if (IsConnected()) { 75 Disconnect(); 76 } 77 78 #if defined(HAVE_LIBCOMPRESSION) 79 if (m_decompression_scratch) 80 free (m_decompression_scratch); 81 #endif 82 } 83 84 char GDBRemoteCommunication::CalculcateChecksum(llvm::StringRef payload) { 85 int checksum = 0; 86 87 for (char c : payload) 88 checksum += c; 89 90 return checksum & 255; 91 } 92 93 size_t GDBRemoteCommunication::SendAck() { 94 Log *log = GetLog(GDBRLog::Packets); 95 ConnectionStatus status = eConnectionStatusSuccess; 96 char ch = '+'; 97 const size_t bytes_written = WriteAll(&ch, 1, status, nullptr); 98 LLDB_LOGF(log, "<%4" PRIu64 "> send packet: %c", (uint64_t)bytes_written, ch); 99 m_history.AddPacket(ch, GDBRemotePacket::ePacketTypeSend, bytes_written); 100 return bytes_written; 101 } 102 103 size_t GDBRemoteCommunication::SendNack() { 104 Log *log = GetLog(GDBRLog::Packets); 105 ConnectionStatus status = eConnectionStatusSuccess; 106 char ch = '-'; 107 const size_t bytes_written = WriteAll(&ch, 1, status, nullptr); 108 LLDB_LOGF(log, "<%4" PRIu64 "> send packet: %c", (uint64_t)bytes_written, ch); 109 m_history.AddPacket(ch, GDBRemotePacket::ePacketTypeSend, bytes_written); 110 return bytes_written; 111 } 112 113 GDBRemoteCommunication::PacketResult 114 GDBRemoteCommunication::SendPacketNoLock(llvm::StringRef payload) { 115 StreamString packet(0, 4, eByteOrderBig); 116 packet.PutChar('$'); 117 packet.Write(payload.data(), payload.size()); 118 packet.PutChar('#'); 119 packet.PutHex8(CalculcateChecksum(payload)); 120 std::string packet_str = std::string(packet.GetString()); 121 122 return SendRawPacketNoLock(packet_str); 123 } 124 125 GDBRemoteCommunication::PacketResult 126 GDBRemoteCommunication::SendNotificationPacketNoLock( 127 llvm::StringRef notify_type, std::deque<std::string> &queue, 128 llvm::StringRef payload) { 129 PacketResult ret = PacketResult::Success; 130 131 // If there are no notification in the queue, send the notification 132 // packet. 133 if (queue.empty()) { 134 StreamString packet(0, 4, eByteOrderBig); 135 packet.PutChar('%'); 136 packet.Write(notify_type.data(), notify_type.size()); 137 packet.PutChar(':'); 138 packet.Write(payload.data(), payload.size()); 139 packet.PutChar('#'); 140 packet.PutHex8(CalculcateChecksum(payload)); 141 ret = SendRawPacketNoLock(packet.GetString(), true); 142 } 143 144 queue.push_back(payload.str()); 145 return ret; 146 } 147 148 GDBRemoteCommunication::PacketResult 149 GDBRemoteCommunication::SendRawPacketNoLock(llvm::StringRef packet, 150 bool skip_ack) { 151 if (IsConnected()) { 152 Log *log = GetLog(GDBRLog::Packets); 153 ConnectionStatus status = eConnectionStatusSuccess; 154 const char *packet_data = packet.data(); 155 const size_t packet_length = packet.size(); 156 size_t bytes_written = WriteAll(packet_data, packet_length, status, nullptr); 157 if (log) { 158 size_t binary_start_offset = 0; 159 if (strncmp(packet_data, "$vFile:pwrite:", strlen("$vFile:pwrite:")) == 160 0) { 161 const char *first_comma = strchr(packet_data, ','); 162 if (first_comma) { 163 const char *second_comma = strchr(first_comma + 1, ','); 164 if (second_comma) 165 binary_start_offset = second_comma - packet_data + 1; 166 } 167 } 168 169 // If logging was just enabled and we have history, then dump out what we 170 // have to the log so we get the historical context. The Dump() call that 171 // logs all of the packet will set a boolean so that we don't dump this 172 // more than once 173 if (!m_history.DidDumpToLog()) 174 m_history.Dump(log); 175 176 if (binary_start_offset) { 177 StreamString strm; 178 // Print non binary data header 179 strm.Printf("<%4" PRIu64 "> send packet: %.*s", (uint64_t)bytes_written, 180 (int)binary_start_offset, packet_data); 181 const uint8_t *p; 182 // Print binary data exactly as sent 183 for (p = (const uint8_t *)packet_data + binary_start_offset; *p != '#'; 184 ++p) 185 strm.Printf("\\x%2.2x", *p); 186 // Print the checksum 187 strm.Printf("%*s", (int)3, p); 188 log->PutString(strm.GetString()); 189 } else 190 LLDB_LOGF(log, "<%4" PRIu64 "> send packet: %.*s", 191 (uint64_t)bytes_written, (int)packet_length, packet_data); 192 } 193 194 m_history.AddPacket(packet.str(), packet_length, 195 GDBRemotePacket::ePacketTypeSend, bytes_written); 196 197 if (bytes_written == packet_length) { 198 if (!skip_ack && GetSendAcks()) 199 return GetAck(); 200 else 201 return PacketResult::Success; 202 } else { 203 LLDB_LOGF(log, "error: failed to send packet: %.*s", (int)packet_length, 204 packet_data); 205 } 206 } 207 return PacketResult::ErrorSendFailed; 208 } 209 210 GDBRemoteCommunication::PacketResult GDBRemoteCommunication::GetAck() { 211 StringExtractorGDBRemote packet; 212 PacketResult result = WaitForPacketNoLock(packet, GetPacketTimeout(), false); 213 if (result == PacketResult::Success) { 214 if (packet.GetResponseType() == 215 StringExtractorGDBRemote::ResponseType::eAck) 216 return PacketResult::Success; 217 else 218 return PacketResult::ErrorSendAck; 219 } 220 return result; 221 } 222 223 GDBRemoteCommunication::PacketResult 224 GDBRemoteCommunication::ReadPacket(StringExtractorGDBRemote &response, 225 Timeout<std::micro> timeout, 226 bool sync_on_timeout) { 227 using ResponseType = StringExtractorGDBRemote::ResponseType; 228 229 Log *log = GetLog(GDBRLog::Packets); 230 for (;;) { 231 PacketResult result = 232 WaitForPacketNoLock(response, timeout, sync_on_timeout); 233 if (result != PacketResult::Success || 234 (response.GetResponseType() != ResponseType::eAck && 235 response.GetResponseType() != ResponseType::eNack)) 236 return result; 237 LLDB_LOG(log, "discarding spurious `{0}` packet", response.GetStringRef()); 238 } 239 } 240 241 GDBRemoteCommunication::PacketResult 242 GDBRemoteCommunication::WaitForPacketNoLock(StringExtractorGDBRemote &packet, 243 Timeout<std::micro> timeout, 244 bool sync_on_timeout) { 245 uint8_t buffer[8192]; 246 Status error; 247 248 Log *log = GetLog(GDBRLog::Packets); 249 250 // Check for a packet from our cache first without trying any reading... 251 if (CheckForPacket(nullptr, 0, packet) != PacketType::Invalid) 252 return PacketResult::Success; 253 254 bool timed_out = false; 255 bool disconnected = false; 256 while (IsConnected() && !timed_out) { 257 lldb::ConnectionStatus status = eConnectionStatusNoConnection; 258 size_t bytes_read = Read(buffer, sizeof(buffer), timeout, status, &error); 259 260 LLDB_LOGV(log, 261 "Read(buffer, sizeof(buffer), timeout = {0}, " 262 "status = {1}, error = {2}) => bytes_read = {3}", 263 timeout, Communication::ConnectionStatusAsString(status), error, 264 bytes_read); 265 266 if (bytes_read > 0) { 267 if (CheckForPacket(buffer, bytes_read, packet) != PacketType::Invalid) 268 return PacketResult::Success; 269 } else { 270 switch (status) { 271 case eConnectionStatusTimedOut: 272 case eConnectionStatusInterrupted: 273 if (sync_on_timeout) { 274 /// Sync the remote GDB server and make sure we get a response that 275 /// corresponds to what we send. 276 /// 277 /// Sends a "qEcho" packet and makes sure it gets the exact packet 278 /// echoed back. If the qEcho packet isn't supported, we send a qC 279 /// packet and make sure we get a valid thread ID back. We use the 280 /// "qC" packet since its response if very unique: is responds with 281 /// "QC%x" where %x is the thread ID of the current thread. This 282 /// makes the response unique enough from other packet responses to 283 /// ensure we are back on track. 284 /// 285 /// This packet is needed after we time out sending a packet so we 286 /// can ensure that we are getting the response for the packet we 287 /// are sending. There are no sequence IDs in the GDB remote 288 /// protocol (there used to be, but they are not supported anymore) 289 /// so if you timeout sending packet "abc", you might then send 290 /// packet "cde" and get the response for the previous "abc" packet. 291 /// Many responses are "OK" or "" (unsupported) or "EXX" (error) so 292 /// many responses for packets can look like responses for other 293 /// packets. So if we timeout, we need to ensure that we can get 294 /// back on track. If we can't get back on track, we must 295 /// disconnect. 296 bool sync_success = false; 297 bool got_actual_response = false; 298 // We timed out, we need to sync back up with the 299 char echo_packet[32]; 300 int echo_packet_len = 0; 301 RegularExpression response_regex; 302 303 if (m_supports_qEcho == eLazyBoolYes) { 304 echo_packet_len = ::snprintf(echo_packet, sizeof(echo_packet), 305 "qEcho:%u", ++m_echo_number); 306 std::string regex_str = "^"; 307 regex_str += echo_packet; 308 regex_str += "$"; 309 response_regex = RegularExpression(regex_str); 310 } else { 311 echo_packet_len = 312 ::snprintf(echo_packet, sizeof(echo_packet), "qC"); 313 response_regex = 314 RegularExpression(llvm::StringRef("^QC[0-9A-Fa-f]+$")); 315 } 316 317 PacketResult echo_packet_result = 318 SendPacketNoLock(llvm::StringRef(echo_packet, echo_packet_len)); 319 if (echo_packet_result == PacketResult::Success) { 320 const uint32_t max_retries = 3; 321 uint32_t successful_responses = 0; 322 for (uint32_t i = 0; i < max_retries; ++i) { 323 StringExtractorGDBRemote echo_response; 324 echo_packet_result = 325 WaitForPacketNoLock(echo_response, timeout, false); 326 if (echo_packet_result == PacketResult::Success) { 327 ++successful_responses; 328 if (response_regex.Execute(echo_response.GetStringRef())) { 329 sync_success = true; 330 break; 331 } else if (successful_responses == 1) { 332 // We got something else back as the first successful 333 // response, it probably is the response to the packet we 334 // actually wanted, so copy it over if this is the first 335 // success and continue to try to get the qEcho response 336 packet = echo_response; 337 got_actual_response = true; 338 } 339 } else if (echo_packet_result == PacketResult::ErrorReplyTimeout) 340 continue; // Packet timed out, continue waiting for a response 341 else 342 break; // Something else went wrong getting the packet back, we 343 // failed and are done trying 344 } 345 } 346 347 // We weren't able to sync back up with the server, we must abort 348 // otherwise all responses might not be from the right packets... 349 if (sync_success) { 350 // We timed out, but were able to recover 351 if (got_actual_response) { 352 // We initially timed out, but we did get a response that came in 353 // before the successful reply to our qEcho packet, so lets say 354 // everything is fine... 355 return PacketResult::Success; 356 } 357 } else { 358 disconnected = true; 359 Disconnect(); 360 } 361 } 362 timed_out = true; 363 break; 364 case eConnectionStatusSuccess: 365 // printf ("status = success but error = %s\n", 366 // error.AsCString("<invalid>")); 367 break; 368 369 case eConnectionStatusEndOfFile: 370 case eConnectionStatusNoConnection: 371 case eConnectionStatusLostConnection: 372 case eConnectionStatusError: 373 disconnected = true; 374 Disconnect(); 375 break; 376 } 377 } 378 } 379 packet.Clear(); 380 if (disconnected) 381 return PacketResult::ErrorDisconnected; 382 if (timed_out) 383 return PacketResult::ErrorReplyTimeout; 384 else 385 return PacketResult::ErrorReplyFailed; 386 } 387 388 bool GDBRemoteCommunication::DecompressPacket() { 389 Log *log = GetLog(GDBRLog::Packets); 390 391 if (!CompressionIsEnabled()) 392 return true; 393 394 size_t pkt_size = m_bytes.size(); 395 396 // Smallest possible compressed packet is $N#00 - an uncompressed empty 397 // reply, most commonly indicating an unsupported packet. Anything less than 398 // 5 characters, it's definitely not a compressed packet. 399 if (pkt_size < 5) 400 return true; 401 402 if (m_bytes[0] != '$' && m_bytes[0] != '%') 403 return true; 404 if (m_bytes[1] != 'C' && m_bytes[1] != 'N') 405 return true; 406 407 size_t hash_mark_idx = m_bytes.find('#'); 408 if (hash_mark_idx == std::string::npos) 409 return true; 410 if (hash_mark_idx + 2 >= m_bytes.size()) 411 return true; 412 413 if (!::isxdigit(m_bytes[hash_mark_idx + 1]) || 414 !::isxdigit(m_bytes[hash_mark_idx + 2])) 415 return true; 416 417 size_t content_length = 418 pkt_size - 419 5; // not counting '$', 'C' | 'N', '#', & the two hex checksum chars 420 size_t content_start = 2; // The first character of the 421 // compressed/not-compressed text of the packet 422 size_t checksum_idx = 423 hash_mark_idx + 424 1; // The first character of the two hex checksum characters 425 426 // Normally size_of_first_packet == m_bytes.size() but m_bytes may contain 427 // multiple packets. size_of_first_packet is the size of the initial packet 428 // which we'll replace with the decompressed version of, leaving the rest of 429 // m_bytes unmodified. 430 size_t size_of_first_packet = hash_mark_idx + 3; 431 432 // Compressed packets ("$C") start with a base10 number which is the size of 433 // the uncompressed payload, then a : and then the compressed data. e.g. 434 // $C1024:<binary>#00 Update content_start and content_length to only include 435 // the <binary> part of the packet. 436 437 uint64_t decompressed_bufsize = ULONG_MAX; 438 if (m_bytes[1] == 'C') { 439 size_t i = content_start; 440 while (i < hash_mark_idx && isdigit(m_bytes[i])) 441 i++; 442 if (i < hash_mark_idx && m_bytes[i] == ':') { 443 i++; 444 content_start = i; 445 content_length = hash_mark_idx - content_start; 446 std::string bufsize_str(m_bytes.data() + 2, i - 2 - 1); 447 errno = 0; 448 decompressed_bufsize = ::strtoul(bufsize_str.c_str(), nullptr, 10); 449 if (errno != 0 || decompressed_bufsize == ULONG_MAX) { 450 m_bytes.erase(0, size_of_first_packet); 451 return false; 452 } 453 } 454 } 455 456 if (GetSendAcks()) { 457 char packet_checksum_cstr[3]; 458 packet_checksum_cstr[0] = m_bytes[checksum_idx]; 459 packet_checksum_cstr[1] = m_bytes[checksum_idx + 1]; 460 packet_checksum_cstr[2] = '\0'; 461 long packet_checksum = strtol(packet_checksum_cstr, nullptr, 16); 462 463 long actual_checksum = CalculcateChecksum( 464 llvm::StringRef(m_bytes).substr(1, hash_mark_idx - 1)); 465 bool success = packet_checksum == actual_checksum; 466 if (!success) { 467 LLDB_LOGF(log, 468 "error: checksum mismatch: %.*s expected 0x%2.2x, got 0x%2.2x", 469 (int)(pkt_size), m_bytes.c_str(), (uint8_t)packet_checksum, 470 (uint8_t)actual_checksum); 471 } 472 // Send the ack or nack if needed 473 if (!success) { 474 SendNack(); 475 m_bytes.erase(0, size_of_first_packet); 476 return false; 477 } else { 478 SendAck(); 479 } 480 } 481 482 if (m_bytes[1] == 'N') { 483 // This packet was not compressed -- delete the 'N' character at the start 484 // and the packet may be processed as-is. 485 m_bytes.erase(1, 1); 486 return true; 487 } 488 489 // Reverse the gdb-remote binary escaping that was done to the compressed 490 // text to guard characters like '$', '#', '}', etc. 491 std::vector<uint8_t> unescaped_content; 492 unescaped_content.reserve(content_length); 493 size_t i = content_start; 494 while (i < hash_mark_idx) { 495 if (m_bytes[i] == '}') { 496 i++; 497 unescaped_content.push_back(m_bytes[i] ^ 0x20); 498 } else { 499 unescaped_content.push_back(m_bytes[i]); 500 } 501 i++; 502 } 503 504 uint8_t *decompressed_buffer = nullptr; 505 size_t decompressed_bytes = 0; 506 507 if (decompressed_bufsize != ULONG_MAX) { 508 decompressed_buffer = (uint8_t *)malloc(decompressed_bufsize); 509 if (decompressed_buffer == nullptr) { 510 m_bytes.erase(0, size_of_first_packet); 511 return false; 512 } 513 } 514 515 #if defined(HAVE_LIBCOMPRESSION) 516 if (m_compression_type == CompressionType::ZlibDeflate || 517 m_compression_type == CompressionType::LZFSE || 518 m_compression_type == CompressionType::LZ4 || 519 m_compression_type == CompressionType::LZMA) { 520 compression_algorithm compression_type; 521 if (m_compression_type == CompressionType::LZFSE) 522 compression_type = COMPRESSION_LZFSE; 523 else if (m_compression_type == CompressionType::ZlibDeflate) 524 compression_type = COMPRESSION_ZLIB; 525 else if (m_compression_type == CompressionType::LZ4) 526 compression_type = COMPRESSION_LZ4_RAW; 527 else if (m_compression_type == CompressionType::LZMA) 528 compression_type = COMPRESSION_LZMA; 529 530 if (m_decompression_scratch_type != m_compression_type) { 531 if (m_decompression_scratch) { 532 free (m_decompression_scratch); 533 m_decompression_scratch = nullptr; 534 } 535 size_t scratchbuf_size = 0; 536 if (m_compression_type == CompressionType::LZFSE) 537 scratchbuf_size = compression_decode_scratch_buffer_size (COMPRESSION_LZFSE); 538 else if (m_compression_type == CompressionType::LZ4) 539 scratchbuf_size = compression_decode_scratch_buffer_size (COMPRESSION_LZ4_RAW); 540 else if (m_compression_type == CompressionType::ZlibDeflate) 541 scratchbuf_size = compression_decode_scratch_buffer_size (COMPRESSION_ZLIB); 542 else if (m_compression_type == CompressionType::LZMA) 543 scratchbuf_size = 544 compression_decode_scratch_buffer_size(COMPRESSION_LZMA); 545 if (scratchbuf_size > 0) { 546 m_decompression_scratch = (void*) malloc (scratchbuf_size); 547 m_decompression_scratch_type = m_compression_type; 548 } 549 } 550 551 if (decompressed_bufsize != ULONG_MAX && decompressed_buffer != nullptr) { 552 decompressed_bytes = compression_decode_buffer( 553 decompressed_buffer, decompressed_bufsize, 554 (uint8_t *)unescaped_content.data(), unescaped_content.size(), 555 m_decompression_scratch, compression_type); 556 } 557 } 558 #endif 559 560 #if LLVM_ENABLE_ZLIB 561 if (decompressed_bytes == 0 && decompressed_bufsize != ULONG_MAX && 562 decompressed_buffer != nullptr && 563 m_compression_type == CompressionType::ZlibDeflate) { 564 z_stream stream; 565 memset(&stream, 0, sizeof(z_stream)); 566 stream.next_in = (Bytef *)unescaped_content.data(); 567 stream.avail_in = (uInt)unescaped_content.size(); 568 stream.total_in = 0; 569 stream.next_out = (Bytef *)decompressed_buffer; 570 stream.avail_out = decompressed_bufsize; 571 stream.total_out = 0; 572 stream.zalloc = Z_NULL; 573 stream.zfree = Z_NULL; 574 stream.opaque = Z_NULL; 575 576 if (inflateInit2(&stream, -15) == Z_OK) { 577 int status = inflate(&stream, Z_NO_FLUSH); 578 inflateEnd(&stream); 579 if (status == Z_STREAM_END) { 580 decompressed_bytes = stream.total_out; 581 } 582 } 583 } 584 #endif 585 586 if (decompressed_bytes == 0 || decompressed_buffer == nullptr) { 587 if (decompressed_buffer) 588 free(decompressed_buffer); 589 m_bytes.erase(0, size_of_first_packet); 590 return false; 591 } 592 593 std::string new_packet; 594 new_packet.reserve(decompressed_bytes + 6); 595 new_packet.push_back(m_bytes[0]); 596 new_packet.append((const char *)decompressed_buffer, decompressed_bytes); 597 new_packet.push_back('#'); 598 if (GetSendAcks()) { 599 uint8_t decompressed_checksum = CalculcateChecksum( 600 llvm::StringRef((const char *)decompressed_buffer, decompressed_bytes)); 601 char decompressed_checksum_str[3]; 602 snprintf(decompressed_checksum_str, 3, "%02x", decompressed_checksum); 603 new_packet.append(decompressed_checksum_str); 604 } else { 605 new_packet.push_back('0'); 606 new_packet.push_back('0'); 607 } 608 609 m_bytes.replace(0, size_of_first_packet, new_packet.data(), 610 new_packet.size()); 611 612 free(decompressed_buffer); 613 return true; 614 } 615 616 GDBRemoteCommunication::PacketType 617 GDBRemoteCommunication::CheckForPacket(const uint8_t *src, size_t src_len, 618 StringExtractorGDBRemote &packet) { 619 // Put the packet data into the buffer in a thread safe fashion 620 std::lock_guard<std::recursive_mutex> guard(m_bytes_mutex); 621 622 Log *log = GetLog(GDBRLog::Packets); 623 624 if (src && src_len > 0) { 625 if (log && log->GetVerbose()) { 626 StreamString s; 627 LLDB_LOGF(log, "GDBRemoteCommunication::%s adding %u bytes: %.*s", 628 __FUNCTION__, (uint32_t)src_len, (uint32_t)src_len, src); 629 } 630 m_bytes.append((const char *)src, src_len); 631 } 632 633 bool isNotifyPacket = false; 634 635 // Parse up the packets into gdb remote packets 636 if (!m_bytes.empty()) { 637 // end_idx must be one past the last valid packet byte. Start it off with 638 // an invalid value that is the same as the current index. 639 size_t content_start = 0; 640 size_t content_length = 0; 641 size_t total_length = 0; 642 size_t checksum_idx = std::string::npos; 643 644 // Size of packet before it is decompressed, for logging purposes 645 size_t original_packet_size = m_bytes.size(); 646 if (CompressionIsEnabled()) { 647 if (!DecompressPacket()) { 648 packet.Clear(); 649 return GDBRemoteCommunication::PacketType::Standard; 650 } 651 } 652 653 switch (m_bytes[0]) { 654 case '+': // Look for ack 655 case '-': // Look for cancel 656 case '\x03': // ^C to halt target 657 content_length = total_length = 1; // The command is one byte long... 658 break; 659 660 case '%': // Async notify packet 661 isNotifyPacket = true; 662 [[fallthrough]]; 663 664 case '$': 665 // Look for a standard gdb packet? 666 { 667 size_t hash_pos = m_bytes.find('#'); 668 if (hash_pos != std::string::npos) { 669 if (hash_pos + 2 < m_bytes.size()) { 670 checksum_idx = hash_pos + 1; 671 // Skip the dollar sign 672 content_start = 1; 673 // Don't include the # in the content or the $ in the content 674 // length 675 content_length = hash_pos - 1; 676 677 total_length = 678 hash_pos + 3; // Skip the # and the two hex checksum bytes 679 } else { 680 // Checksum bytes aren't all here yet 681 content_length = std::string::npos; 682 } 683 } 684 } 685 break; 686 687 default: { 688 // We have an unexpected byte and we need to flush all bad data that is 689 // in m_bytes, so we need to find the first byte that is a '+' (ACK), '-' 690 // (NACK), \x03 (CTRL+C interrupt), or '$' character (start of packet 691 // header) or of course, the end of the data in m_bytes... 692 const size_t bytes_len = m_bytes.size(); 693 bool done = false; 694 uint32_t idx; 695 for (idx = 1; !done && idx < bytes_len; ++idx) { 696 switch (m_bytes[idx]) { 697 case '+': 698 case '-': 699 case '\x03': 700 case '%': 701 case '$': 702 done = true; 703 break; 704 705 default: 706 break; 707 } 708 } 709 LLDB_LOGF(log, "GDBRemoteCommunication::%s tossing %u junk bytes: '%.*s'", 710 __FUNCTION__, idx - 1, idx - 1, m_bytes.c_str()); 711 m_bytes.erase(0, idx - 1); 712 } break; 713 } 714 715 if (content_length == std::string::npos) { 716 packet.Clear(); 717 return GDBRemoteCommunication::PacketType::Invalid; 718 } else if (total_length > 0) { 719 720 // We have a valid packet... 721 assert(content_length <= m_bytes.size()); 722 assert(total_length <= m_bytes.size()); 723 assert(content_length <= total_length); 724 size_t content_end = content_start + content_length; 725 726 bool success = true; 727 if (log) { 728 // If logging was just enabled and we have history, then dump out what 729 // we have to the log so we get the historical context. The Dump() call 730 // that logs all of the packet will set a boolean so that we don't dump 731 // this more than once 732 if (!m_history.DidDumpToLog()) 733 m_history.Dump(log); 734 735 bool binary = false; 736 // Only detect binary for packets that start with a '$' and have a 737 // '#CC' checksum 738 if (m_bytes[0] == '$' && total_length > 4) { 739 for (size_t i = 0; !binary && i < total_length; ++i) { 740 unsigned char c = m_bytes[i]; 741 if (!llvm::isPrint(c) && !llvm::isSpace(c)) { 742 binary = true; 743 } 744 } 745 } 746 if (binary) { 747 StreamString strm; 748 // Packet header... 749 if (CompressionIsEnabled()) 750 strm.Printf("<%4" PRIu64 ":%" PRIu64 "> read packet: %c", 751 (uint64_t)original_packet_size, (uint64_t)total_length, 752 m_bytes[0]); 753 else 754 strm.Printf("<%4" PRIu64 "> read packet: %c", 755 (uint64_t)total_length, m_bytes[0]); 756 for (size_t i = content_start; i < content_end; ++i) { 757 // Remove binary escaped bytes when displaying the packet... 758 const char ch = m_bytes[i]; 759 if (ch == 0x7d) { 760 // 0x7d is the escape character. The next character is to be 761 // XOR'd with 0x20. 762 const char escapee = m_bytes[++i] ^ 0x20; 763 strm.Printf("%2.2x", escapee); 764 } else { 765 strm.Printf("%2.2x", (uint8_t)ch); 766 } 767 } 768 // Packet footer... 769 strm.Printf("%c%c%c", m_bytes[total_length - 3], 770 m_bytes[total_length - 2], m_bytes[total_length - 1]); 771 log->PutString(strm.GetString()); 772 } else { 773 if (CompressionIsEnabled()) 774 LLDB_LOGF(log, "<%4" PRIu64 ":%" PRIu64 "> read packet: %.*s", 775 (uint64_t)original_packet_size, (uint64_t)total_length, 776 (int)(total_length), m_bytes.c_str()); 777 else 778 LLDB_LOGF(log, "<%4" PRIu64 "> read packet: %.*s", 779 (uint64_t)total_length, (int)(total_length), 780 m_bytes.c_str()); 781 } 782 } 783 784 m_history.AddPacket(m_bytes, total_length, 785 GDBRemotePacket::ePacketTypeRecv, total_length); 786 787 // Copy the packet from m_bytes to packet_str expanding the run-length 788 // encoding in the process. 789 std ::string packet_str = 790 ExpandRLE(m_bytes.substr(content_start, content_end - content_start)); 791 packet = StringExtractorGDBRemote(packet_str); 792 793 if (m_bytes[0] == '$' || m_bytes[0] == '%') { 794 assert(checksum_idx < m_bytes.size()); 795 if (::isxdigit(m_bytes[checksum_idx + 0]) || 796 ::isxdigit(m_bytes[checksum_idx + 1])) { 797 if (GetSendAcks()) { 798 const char *packet_checksum_cstr = &m_bytes[checksum_idx]; 799 char packet_checksum = strtol(packet_checksum_cstr, nullptr, 16); 800 char actual_checksum = CalculcateChecksum( 801 llvm::StringRef(m_bytes).slice(content_start, content_end)); 802 success = packet_checksum == actual_checksum; 803 if (!success) { 804 LLDB_LOGF(log, 805 "error: checksum mismatch: %.*s expected 0x%2.2x, " 806 "got 0x%2.2x", 807 (int)(total_length), m_bytes.c_str(), 808 (uint8_t)packet_checksum, (uint8_t)actual_checksum); 809 } 810 // Send the ack or nack if needed 811 if (!success) 812 SendNack(); 813 else 814 SendAck(); 815 } 816 } else { 817 success = false; 818 LLDB_LOGF(log, "error: invalid checksum in packet: '%s'\n", 819 m_bytes.c_str()); 820 } 821 } 822 823 m_bytes.erase(0, total_length); 824 packet.SetFilePos(0); 825 826 if (isNotifyPacket) 827 return GDBRemoteCommunication::PacketType::Notify; 828 else 829 return GDBRemoteCommunication::PacketType::Standard; 830 } 831 } 832 packet.Clear(); 833 return GDBRemoteCommunication::PacketType::Invalid; 834 } 835 836 Status GDBRemoteCommunication::StartListenThread(const char *hostname, 837 uint16_t port) { 838 if (m_listen_thread.IsJoinable()) 839 return Status::FromErrorString("listen thread already running"); 840 841 char listen_url[512]; 842 if (hostname && hostname[0]) 843 snprintf(listen_url, sizeof(listen_url), "listen://%s:%i", hostname, port); 844 else 845 snprintf(listen_url, sizeof(listen_url), "listen://%i", port); 846 m_listen_url = listen_url; 847 SetConnection(std::make_unique<ConnectionFileDescriptor>()); 848 llvm::Expected<HostThread> listen_thread = ThreadLauncher::LaunchThread( 849 listen_url, [this] { return GDBRemoteCommunication::ListenThread(); }); 850 if (!listen_thread) 851 return Status::FromError(listen_thread.takeError()); 852 m_listen_thread = *listen_thread; 853 854 return Status(); 855 } 856 857 bool GDBRemoteCommunication::JoinListenThread() { 858 if (m_listen_thread.IsJoinable()) 859 m_listen_thread.Join(nullptr); 860 return true; 861 } 862 863 lldb::thread_result_t GDBRemoteCommunication::ListenThread() { 864 Status error; 865 ConnectionFileDescriptor *connection = 866 (ConnectionFileDescriptor *)GetConnection(); 867 868 if (connection) { 869 // Do the listen on another thread so we can continue on... 870 if (connection->Connect( 871 m_listen_url.c_str(), 872 [this](llvm::StringRef port_str) { 873 uint16_t port = 0; 874 llvm::to_integer(port_str, port, 10); 875 m_port_promise.set_value(port); 876 }, 877 &error) != eConnectionStatusSuccess) 878 SetConnection(nullptr); 879 } 880 return {}; 881 } 882 883 FileSpec GDBRemoteCommunication::GetDebugserverPath(Platform *platform) { 884 Log *log = GetLog(GDBRLog::Process); 885 // If we locate debugserver, keep that located version around 886 static FileSpec g_debugserver_file_spec; 887 FileSpec debugserver_file_spec; 888 889 Environment host_env = Host::GetEnvironment(); 890 891 // Always check to see if we have an environment override for the path to the 892 // debugserver to use and use it if we do. 893 std::string env_debugserver_path = host_env.lookup("LLDB_DEBUGSERVER_PATH"); 894 if (!env_debugserver_path.empty()) { 895 debugserver_file_spec.SetFile(env_debugserver_path, 896 FileSpec::Style::native); 897 LLDB_LOGF(log, 898 "GDBRemoteCommunication::%s() gdb-remote stub exe path set " 899 "from environment variable: %s", 900 __FUNCTION__, env_debugserver_path.c_str()); 901 } else 902 debugserver_file_spec = g_debugserver_file_spec; 903 bool debugserver_exists = 904 FileSystem::Instance().Exists(debugserver_file_spec); 905 if (!debugserver_exists) { 906 // The debugserver binary is in the LLDB.framework/Resources directory. 907 debugserver_file_spec = HostInfo::GetSupportExeDir(); 908 if (debugserver_file_spec) { 909 debugserver_file_spec.AppendPathComponent(DEBUGSERVER_BASENAME); 910 debugserver_exists = FileSystem::Instance().Exists(debugserver_file_spec); 911 if (debugserver_exists) { 912 LLDB_LOGF(log, 913 "GDBRemoteCommunication::%s() found gdb-remote stub exe '%s'", 914 __FUNCTION__, debugserver_file_spec.GetPath().c_str()); 915 916 g_debugserver_file_spec = debugserver_file_spec; 917 } else { 918 if (platform) 919 debugserver_file_spec = 920 platform->LocateExecutable(DEBUGSERVER_BASENAME); 921 else 922 debugserver_file_spec.Clear(); 923 if (debugserver_file_spec) { 924 // Platform::LocateExecutable() wouldn't return a path if it doesn't 925 // exist 926 debugserver_exists = true; 927 } else { 928 LLDB_LOGF(log, 929 "GDBRemoteCommunication::%s() could not find " 930 "gdb-remote stub exe '%s'", 931 __FUNCTION__, debugserver_file_spec.GetPath().c_str()); 932 } 933 // Don't cache the platform specific GDB server binary as it could 934 // change from platform to platform 935 g_debugserver_file_spec.Clear(); 936 } 937 } 938 } 939 return debugserver_file_spec; 940 } 941 942 Status GDBRemoteCommunication::StartDebugserverProcess( 943 const char *url, Platform *platform, ProcessLaunchInfo &launch_info, 944 uint16_t *port, const Args *inferior_args, shared_fd_t pass_comm_fd) { 945 Log *log = GetLog(GDBRLog::Process); 946 LLDB_LOGF(log, "GDBRemoteCommunication::%s(url=%s, port=%" PRIu16 ")", 947 __FUNCTION__, url ? url : "<empty>", port ? *port : uint16_t(0)); 948 949 Status error; 950 FileSpec &debugserver_file_spec = launch_info.GetExecutableFile(); 951 if ((debugserver_file_spec = GetDebugserverPath(platform))) { 952 std::string debugserver_path = debugserver_file_spec.GetPath(); 953 954 Args &debugserver_args = launch_info.GetArguments(); 955 debugserver_args.Clear(); 956 957 // Start args with "debugserver /file/path -r --" 958 debugserver_args.AppendArgument(llvm::StringRef(debugserver_path)); 959 960 #if !defined(__APPLE__) 961 // First argument to lldb-server must be mode in which to run. 962 debugserver_args.AppendArgument(llvm::StringRef("gdbserver")); 963 #endif 964 965 // If a url is supplied then use it 966 if (url && url[0]) 967 debugserver_args.AppendArgument(llvm::StringRef(url)); 968 969 if (pass_comm_fd != SharedSocket::kInvalidFD) { 970 StreamString fd_arg; 971 fd_arg.Printf("--fd=%" PRIi64, (int64_t)pass_comm_fd); 972 debugserver_args.AppendArgument(fd_arg.GetString()); 973 // Send "pass_comm_fd" down to the inferior so it can use it to 974 // communicate back with this process. Ignored on Windows. 975 #ifndef _WIN32 976 launch_info.AppendDuplicateFileAction((int)pass_comm_fd, 977 (int)pass_comm_fd); 978 #endif 979 } 980 981 // use native registers, not the GDB registers 982 debugserver_args.AppendArgument(llvm::StringRef("--native-regs")); 983 984 if (launch_info.GetLaunchInSeparateProcessGroup()) { 985 debugserver_args.AppendArgument(llvm::StringRef("--setsid")); 986 } 987 988 llvm::SmallString<128> named_pipe_path; 989 // socket_pipe is used by debug server to communicate back either 990 // TCP port or domain socket name which it listens on. 991 // The second purpose of the pipe to serve as a synchronization point - 992 // once data is written to the pipe, debug server is up and running. 993 Pipe socket_pipe; 994 995 // port is null when debug server should listen on domain socket - we're 996 // not interested in port value but rather waiting for debug server to 997 // become available. 998 if (pass_comm_fd == SharedSocket::kInvalidFD) { 999 if (url) { 1000 // Create a temporary file to get the stdout/stderr and redirect the output of 1001 // the command into this file. We will later read this file if all goes well 1002 // and fill the data into "command_output_ptr" 1003 #if defined(__APPLE__) 1004 // Binding to port zero, we need to figure out what port it ends up 1005 // using using a named pipe... 1006 error = socket_pipe.CreateWithUniqueName("debugserver-named-pipe", 1007 false, named_pipe_path); 1008 if (error.Fail()) { 1009 LLDB_LOGF(log, 1010 "GDBRemoteCommunication::%s() " 1011 "named pipe creation failed: %s", 1012 __FUNCTION__, error.AsCString()); 1013 return error; 1014 } 1015 debugserver_args.AppendArgument(llvm::StringRef("--named-pipe")); 1016 debugserver_args.AppendArgument(named_pipe_path); 1017 #else 1018 // Binding to port zero, we need to figure out what port it ends up 1019 // using using an unnamed pipe... 1020 error = socket_pipe.CreateNew(true); 1021 if (error.Fail()) { 1022 LLDB_LOGF(log, 1023 "GDBRemoteCommunication::%s() " 1024 "unnamed pipe creation failed: %s", 1025 __FUNCTION__, error.AsCString()); 1026 return error; 1027 } 1028 pipe_t write = socket_pipe.GetWritePipe(); 1029 debugserver_args.AppendArgument(llvm::StringRef("--pipe")); 1030 debugserver_args.AppendArgument(llvm::to_string(write)); 1031 launch_info.AppendCloseFileAction(socket_pipe.GetReadFileDescriptor()); 1032 #endif 1033 } else { 1034 // No host and port given, so lets listen on our end and make the 1035 // debugserver connect to us.. 1036 error = StartListenThread("127.0.0.1", 0); 1037 if (error.Fail()) { 1038 LLDB_LOGF(log, 1039 "GDBRemoteCommunication::%s() unable to start listen " 1040 "thread: %s", 1041 __FUNCTION__, error.AsCString()); 1042 return error; 1043 } 1044 1045 // Wait for 10 seconds to resolve the bound port 1046 std::future<uint16_t> port_future = m_port_promise.get_future(); 1047 uint16_t port_ = port_future.wait_for(std::chrono::seconds(10)) == 1048 std::future_status::ready 1049 ? port_future.get() 1050 : 0; 1051 if (port_ > 0) { 1052 char port_cstr[32]; 1053 snprintf(port_cstr, sizeof(port_cstr), "127.0.0.1:%i", port_); 1054 // Send the host and port down that debugserver and specify an option 1055 // so that it connects back to the port we are listening to in this 1056 // process 1057 debugserver_args.AppendArgument(llvm::StringRef("--reverse-connect")); 1058 debugserver_args.AppendArgument(llvm::StringRef(port_cstr)); 1059 if (port) 1060 *port = port_; 1061 } else { 1062 LLDB_LOGF(log, "GDBRemoteCommunication::%s() failed: %s", 1063 __FUNCTION__, error.AsCString()); 1064 return Status::FromErrorString( 1065 "failed to bind to port 0 on 127.0.0.1"); 1066 } 1067 } 1068 } 1069 1070 Environment host_env = Host::GetEnvironment(); 1071 std::string env_debugserver_log_file = 1072 host_env.lookup("LLDB_DEBUGSERVER_LOG_FILE"); 1073 if (!env_debugserver_log_file.empty()) { 1074 debugserver_args.AppendArgument( 1075 llvm::formatv("--log-file={0}", env_debugserver_log_file).str()); 1076 } 1077 1078 #if defined(__APPLE__) 1079 const char *env_debugserver_log_flags = 1080 getenv("LLDB_DEBUGSERVER_LOG_FLAGS"); 1081 if (env_debugserver_log_flags) { 1082 debugserver_args.AppendArgument( 1083 llvm::formatv("--log-flags={0}", env_debugserver_log_flags).str()); 1084 } 1085 #else 1086 std::string env_debugserver_log_channels = 1087 host_env.lookup("LLDB_SERVER_LOG_CHANNELS"); 1088 if (!env_debugserver_log_channels.empty()) { 1089 debugserver_args.AppendArgument( 1090 llvm::formatv("--log-channels={0}", env_debugserver_log_channels) 1091 .str()); 1092 } 1093 #endif 1094 1095 // Add additional args, starting with LLDB_DEBUGSERVER_EXTRA_ARG_1 until an 1096 // env var doesn't come back. 1097 uint32_t env_var_index = 1; 1098 bool has_env_var; 1099 do { 1100 char env_var_name[64]; 1101 snprintf(env_var_name, sizeof(env_var_name), 1102 "LLDB_DEBUGSERVER_EXTRA_ARG_%" PRIu32, env_var_index++); 1103 std::string extra_arg = host_env.lookup(env_var_name); 1104 has_env_var = !extra_arg.empty(); 1105 1106 if (has_env_var) { 1107 debugserver_args.AppendArgument(llvm::StringRef(extra_arg)); 1108 LLDB_LOGF(log, 1109 "GDBRemoteCommunication::%s adding env var %s contents " 1110 "to stub command line (%s)", 1111 __FUNCTION__, env_var_name, extra_arg.c_str()); 1112 } 1113 } while (has_env_var); 1114 1115 if (inferior_args && inferior_args->GetArgumentCount() > 0) { 1116 debugserver_args.AppendArgument(llvm::StringRef("--")); 1117 debugserver_args.AppendArguments(*inferior_args); 1118 } 1119 1120 // Copy the current environment to the gdbserver/debugserver instance 1121 launch_info.GetEnvironment() = host_env; 1122 1123 // Close STDIN, STDOUT and STDERR. 1124 launch_info.AppendCloseFileAction(STDIN_FILENO); 1125 launch_info.AppendCloseFileAction(STDOUT_FILENO); 1126 launch_info.AppendCloseFileAction(STDERR_FILENO); 1127 1128 // Redirect STDIN, STDOUT and STDERR to "/dev/null". 1129 launch_info.AppendSuppressFileAction(STDIN_FILENO, true, false); 1130 launch_info.AppendSuppressFileAction(STDOUT_FILENO, false, true); 1131 launch_info.AppendSuppressFileAction(STDERR_FILENO, false, true); 1132 1133 if (log) { 1134 StreamString string_stream; 1135 Platform *const platform = nullptr; 1136 launch_info.Dump(string_stream, platform); 1137 LLDB_LOGF(log, "launch info for gdb-remote stub:\n%s", 1138 string_stream.GetData()); 1139 } 1140 error = Host::LaunchProcess(launch_info); 1141 1142 if (error.Success() && 1143 (launch_info.GetProcessID() != LLDB_INVALID_PROCESS_ID) && 1144 pass_comm_fd == SharedSocket::kInvalidFD) { 1145 if (named_pipe_path.size() > 0) { 1146 error = socket_pipe.OpenAsReader(named_pipe_path, false); 1147 if (error.Fail()) 1148 LLDB_LOGF(log, 1149 "GDBRemoteCommunication::%s() " 1150 "failed to open named pipe %s for reading: %s", 1151 __FUNCTION__, named_pipe_path.c_str(), error.AsCString()); 1152 } 1153 1154 if (socket_pipe.CanWrite()) 1155 socket_pipe.CloseWriteFileDescriptor(); 1156 if (socket_pipe.CanRead()) { 1157 // The port number may be up to "65535\0". 1158 char port_cstr[6] = {0}; 1159 size_t num_bytes = sizeof(port_cstr); 1160 // Read port from pipe with 10 second timeout. 1161 error = socket_pipe.ReadWithTimeout( 1162 port_cstr, num_bytes, std::chrono::seconds{10}, num_bytes); 1163 if (error.Success() && (port != nullptr)) { 1164 assert(num_bytes > 0 && port_cstr[num_bytes - 1] == '\0'); 1165 uint16_t child_port = 0; 1166 // FIXME: improve error handling 1167 llvm::to_integer(port_cstr, child_port); 1168 if (*port == 0 || *port == child_port) { 1169 *port = child_port; 1170 LLDB_LOGF(log, 1171 "GDBRemoteCommunication::%s() " 1172 "debugserver listens %u port", 1173 __FUNCTION__, *port); 1174 } else { 1175 LLDB_LOGF(log, 1176 "GDBRemoteCommunication::%s() " 1177 "debugserver listening on port " 1178 "%d but requested port was %d", 1179 __FUNCTION__, (uint32_t)child_port, (uint32_t)(*port)); 1180 } 1181 } else { 1182 LLDB_LOGF(log, 1183 "GDBRemoteCommunication::%s() " 1184 "failed to read a port value from pipe %s: %s", 1185 __FUNCTION__, named_pipe_path.c_str(), error.AsCString()); 1186 } 1187 socket_pipe.Close(); 1188 } 1189 1190 if (named_pipe_path.size() > 0) { 1191 const auto err = socket_pipe.Delete(named_pipe_path); 1192 if (err.Fail()) { 1193 LLDB_LOGF(log, 1194 "GDBRemoteCommunication::%s failed to delete pipe %s: %s", 1195 __FUNCTION__, named_pipe_path.c_str(), err.AsCString()); 1196 } 1197 } 1198 1199 // Make sure we actually connect with the debugserver... 1200 JoinListenThread(); 1201 } 1202 } else { 1203 error = Status::FromErrorString("unable to locate " DEBUGSERVER_BASENAME); 1204 } 1205 1206 if (error.Fail()) { 1207 LLDB_LOGF(log, "GDBRemoteCommunication::%s() failed: %s", __FUNCTION__, 1208 error.AsCString()); 1209 } 1210 1211 return error; 1212 } 1213 1214 void GDBRemoteCommunication::DumpHistory(Stream &strm) { m_history.Dump(strm); } 1215 1216 llvm::Error 1217 GDBRemoteCommunication::ConnectLocally(GDBRemoteCommunication &client, 1218 GDBRemoteCommunication &server) { 1219 const int backlog = 5; 1220 TCPSocket listen_socket(true); 1221 if (llvm::Error error = 1222 listen_socket.Listen("localhost:0", backlog).ToError()) 1223 return error; 1224 1225 llvm::SmallString<32> remote_addr; 1226 llvm::raw_svector_ostream(remote_addr) 1227 << "connect://localhost:" << listen_socket.GetLocalPortNumber(); 1228 1229 std::unique_ptr<ConnectionFileDescriptor> conn_up( 1230 new ConnectionFileDescriptor()); 1231 Status status; 1232 if (conn_up->Connect(remote_addr, &status) != lldb::eConnectionStatusSuccess) 1233 return llvm::createStringError(llvm::inconvertibleErrorCode(), 1234 "Unable to connect: %s", status.AsCString()); 1235 1236 // The connection was already established above, so a short timeout is 1237 // sufficient. 1238 Socket *accept_socket = nullptr; 1239 if (Status accept_status = 1240 listen_socket.Accept(std::chrono::seconds(1), accept_socket); 1241 accept_status.Fail()) 1242 return accept_status.takeError(); 1243 1244 client.SetConnection(std::move(conn_up)); 1245 server.SetConnection( 1246 std::make_unique<ConnectionFileDescriptor>(accept_socket)); 1247 return llvm::Error::success(); 1248 } 1249 1250 GDBRemoteCommunication::ScopedTimeout::ScopedTimeout( 1251 GDBRemoteCommunication &gdb_comm, std::chrono::seconds timeout) 1252 : m_gdb_comm(gdb_comm), m_saved_timeout(0), m_timeout_modified(false) { 1253 auto curr_timeout = gdb_comm.GetPacketTimeout(); 1254 // Only update the timeout if the timeout is greater than the current 1255 // timeout. If the current timeout is larger, then just use that. 1256 if (curr_timeout < timeout) { 1257 m_timeout_modified = true; 1258 m_saved_timeout = m_gdb_comm.SetPacketTimeout(timeout); 1259 } 1260 } 1261 1262 GDBRemoteCommunication::ScopedTimeout::~ScopedTimeout() { 1263 // Only restore the timeout if we set it in the constructor. 1264 if (m_timeout_modified) 1265 m_gdb_comm.SetPacketTimeout(m_saved_timeout); 1266 } 1267 1268 void llvm::format_provider<GDBRemoteCommunication::PacketResult>::format( 1269 const GDBRemoteCommunication::PacketResult &result, raw_ostream &Stream, 1270 StringRef Style) { 1271 using PacketResult = GDBRemoteCommunication::PacketResult; 1272 1273 switch (result) { 1274 case PacketResult::Success: 1275 Stream << "Success"; 1276 break; 1277 case PacketResult::ErrorSendFailed: 1278 Stream << "ErrorSendFailed"; 1279 break; 1280 case PacketResult::ErrorSendAck: 1281 Stream << "ErrorSendAck"; 1282 break; 1283 case PacketResult::ErrorReplyFailed: 1284 Stream << "ErrorReplyFailed"; 1285 break; 1286 case PacketResult::ErrorReplyTimeout: 1287 Stream << "ErrorReplyTimeout"; 1288 break; 1289 case PacketResult::ErrorReplyInvalid: 1290 Stream << "ErrorReplyInvalid"; 1291 break; 1292 case PacketResult::ErrorReplyAck: 1293 Stream << "ErrorReplyAck"; 1294 break; 1295 case PacketResult::ErrorDisconnected: 1296 Stream << "ErrorDisconnected"; 1297 break; 1298 case PacketResult::ErrorNoSequenceLock: 1299 Stream << "ErrorNoSequenceLock"; 1300 break; 1301 } 1302 } 1303 1304 std::string GDBRemoteCommunication::ExpandRLE(std::string packet) { 1305 // Reserve enough byte for the most common case (no RLE used). 1306 std::string decoded; 1307 decoded.reserve(packet.size()); 1308 for (std::string::const_iterator c = packet.begin(); c != packet.end(); ++c) { 1309 if (*c == '*') { 1310 // '*' indicates RLE. Next character will give us the repeat count and 1311 // previous character is what is to be repeated. 1312 char char_to_repeat = decoded.back(); 1313 // Number of time the previous character is repeated. 1314 int repeat_count = *++c + 3 - ' '; 1315 // We have the char_to_repeat and repeat_count. Now push it in the 1316 // packet. 1317 for (int i = 0; i < repeat_count; ++i) 1318 decoded.push_back(char_to_repeat); 1319 } else if (*c == 0x7d) { 1320 // 0x7d is the escape character. The next character is to be XOR'd with 1321 // 0x20. 1322 char escapee = *++c ^ 0x20; 1323 decoded.push_back(escapee); 1324 } else { 1325 decoded.push_back(*c); 1326 } 1327 } 1328 return decoded; 1329 } 1330