1 //===-- PlatformPOSIX.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 "PlatformPOSIX.h" 10 11 #include "Plugins/Platform/gdb-server/PlatformRemoteGDBServer.h" 12 #include "Plugins/TypeSystem/Clang/TypeSystemClang.h" 13 #include "lldb/Core/Debugger.h" 14 #include "lldb/Core/Module.h" 15 #include "lldb/Expression/DiagnosticManager.h" 16 #include "lldb/Expression/FunctionCaller.h" 17 #include "lldb/Expression/UserExpression.h" 18 #include "lldb/Expression/UtilityFunction.h" 19 #include "lldb/Host/File.h" 20 #include "lldb/Host/FileCache.h" 21 #include "lldb/Host/FileSystem.h" 22 #include "lldb/Host/Host.h" 23 #include "lldb/Host/HostInfo.h" 24 #include "lldb/Host/ProcessLaunchInfo.h" 25 #include "lldb/Target/DynamicLoader.h" 26 #include "lldb/Target/ExecutionContext.h" 27 #include "lldb/Target/Process.h" 28 #include "lldb/Target/Thread.h" 29 #include "lldb/Utility/DataBufferHeap.h" 30 #include "lldb/Utility/FileSpec.h" 31 #include "lldb/Utility/LLDBLog.h" 32 #include "lldb/Utility/Log.h" 33 #include "lldb/Utility/StreamString.h" 34 #include "lldb/ValueObject/ValueObject.h" 35 #include "llvm/ADT/ScopeExit.h" 36 #include <optional> 37 38 using namespace lldb; 39 using namespace lldb_private; 40 41 /// Default Constructor 42 PlatformPOSIX::PlatformPOSIX(bool is_host) 43 : RemoteAwarePlatform(is_host), // This is the local host platform 44 m_option_group_platform_rsync(new OptionGroupPlatformRSync()), 45 m_option_group_platform_ssh(new OptionGroupPlatformSSH()), 46 m_option_group_platform_caching(new OptionGroupPlatformCaching()) {} 47 48 /// Destructor. 49 /// 50 /// The destructor is virtual since this class is designed to be 51 /// inherited from by the plug-in instance. 52 PlatformPOSIX::~PlatformPOSIX() = default; 53 54 lldb_private::OptionGroupOptions *PlatformPOSIX::GetConnectionOptions( 55 lldb_private::CommandInterpreter &interpreter) { 56 auto iter = m_options.find(&interpreter), end = m_options.end(); 57 if (iter == end) { 58 std::unique_ptr<lldb_private::OptionGroupOptions> options( 59 new OptionGroupOptions()); 60 options->Append(m_option_group_platform_rsync.get()); 61 options->Append(m_option_group_platform_ssh.get()); 62 options->Append(m_option_group_platform_caching.get()); 63 m_options[&interpreter] = std::move(options); 64 } 65 66 return m_options.at(&interpreter).get(); 67 } 68 69 static uint32_t chown_file(Platform *platform, const char *path, 70 uint32_t uid = UINT32_MAX, 71 uint32_t gid = UINT32_MAX) { 72 if (!platform || !path || *path == 0) 73 return UINT32_MAX; 74 75 if (uid == UINT32_MAX && gid == UINT32_MAX) 76 return 0; // pretend I did chown correctly - actually I just didn't care 77 78 StreamString command; 79 command.PutCString("chown "); 80 if (uid != UINT32_MAX) 81 command.Printf("%d", uid); 82 if (gid != UINT32_MAX) 83 command.Printf(":%d", gid); 84 command.Printf("%s", path); 85 int status; 86 platform->RunShellCommand(command.GetData(), FileSpec(), &status, nullptr, 87 nullptr, std::chrono::seconds(10)); 88 return status; 89 } 90 91 lldb_private::Status 92 PlatformPOSIX::PutFile(const lldb_private::FileSpec &source, 93 const lldb_private::FileSpec &destination, uint32_t uid, 94 uint32_t gid) { 95 Log *log = GetLog(LLDBLog::Platform); 96 97 if (IsHost()) { 98 if (source == destination) 99 return Status(); 100 // cp src dst 101 // chown uid:gid dst 102 std::string src_path(source.GetPath()); 103 if (src_path.empty()) 104 return Status::FromErrorString("unable to get file path for source"); 105 std::string dst_path(destination.GetPath()); 106 if (dst_path.empty()) 107 return Status::FromErrorString("unable to get file path for destination"); 108 StreamString command; 109 command.Printf("cp %s %s", src_path.c_str(), dst_path.c_str()); 110 int status; 111 RunShellCommand(command.GetData(), FileSpec(), &status, nullptr, nullptr, 112 std::chrono::seconds(10)); 113 if (status != 0) 114 return Status::FromErrorString("unable to perform copy"); 115 if (uid == UINT32_MAX && gid == UINT32_MAX) 116 return Status(); 117 if (chown_file(this, dst_path.c_str(), uid, gid) != 0) 118 return Status::FromErrorString("unable to perform chown"); 119 return Status(); 120 } else if (m_remote_platform_sp) { 121 if (GetSupportsRSync()) { 122 std::string src_path(source.GetPath()); 123 if (src_path.empty()) 124 return Status::FromErrorString("unable to get file path for source"); 125 std::string dst_path(destination.GetPath()); 126 if (dst_path.empty()) 127 return Status::FromErrorString( 128 "unable to get file path for destination"); 129 StreamString command; 130 if (GetIgnoresRemoteHostname()) { 131 if (!GetRSyncPrefix()) 132 command.Printf("rsync %s %s %s", GetRSyncOpts(), src_path.c_str(), 133 dst_path.c_str()); 134 else 135 command.Printf("rsync %s %s %s%s", GetRSyncOpts(), src_path.c_str(), 136 GetRSyncPrefix(), dst_path.c_str()); 137 } else 138 command.Printf("rsync %s %s %s:%s", GetRSyncOpts(), src_path.c_str(), 139 GetHostname(), dst_path.c_str()); 140 LLDB_LOGF(log, "[PutFile] Running command: %s\n", command.GetData()); 141 int retcode; 142 Host::RunShellCommand(command.GetData(), FileSpec(), &retcode, nullptr, 143 nullptr, std::chrono::minutes(1)); 144 if (retcode == 0) { 145 // Don't chown a local file for a remote system 146 // if (chown_file(this,dst_path.c_str(),uid,gid) != 0) 147 // return Status::FromErrorString("unable to perform 148 // chown"); 149 return Status(); 150 } 151 // if we are still here rsync has failed - let's try the slow way before 152 // giving up 153 } 154 } 155 return Platform::PutFile(source, destination, uid, gid); 156 } 157 158 lldb_private::Status PlatformPOSIX::GetFile( 159 const lldb_private::FileSpec &source, // remote file path 160 const lldb_private::FileSpec &destination) // local file path 161 { 162 Log *log = GetLog(LLDBLog::Platform); 163 164 // Check the args, first. 165 std::string src_path(source.GetPath()); 166 if (src_path.empty()) 167 return Status::FromErrorString("unable to get file path for source"); 168 std::string dst_path(destination.GetPath()); 169 if (dst_path.empty()) 170 return Status::FromErrorString("unable to get file path for destination"); 171 if (IsHost()) { 172 if (source == destination) 173 return Status::FromErrorString( 174 "local scenario->source and destination are the same file " 175 "path: no operation performed"); 176 // cp src dst 177 StreamString cp_command; 178 cp_command.Printf("cp %s %s", src_path.c_str(), dst_path.c_str()); 179 int status; 180 RunShellCommand(cp_command.GetData(), FileSpec(), &status, nullptr, nullptr, 181 std::chrono::seconds(10)); 182 if (status != 0) 183 return Status::FromErrorString("unable to perform copy"); 184 return Status(); 185 } else if (m_remote_platform_sp) { 186 if (GetSupportsRSync()) { 187 StreamString command; 188 if (GetIgnoresRemoteHostname()) { 189 if (!GetRSyncPrefix()) 190 command.Printf("rsync %s %s %s", GetRSyncOpts(), src_path.c_str(), 191 dst_path.c_str()); 192 else 193 command.Printf("rsync %s %s%s %s", GetRSyncOpts(), GetRSyncPrefix(), 194 src_path.c_str(), dst_path.c_str()); 195 } else 196 command.Printf("rsync %s %s:%s %s", GetRSyncOpts(), 197 m_remote_platform_sp->GetHostname(), src_path.c_str(), 198 dst_path.c_str()); 199 LLDB_LOGF(log, "[GetFile] Running command: %s\n", command.GetData()); 200 int retcode; 201 Host::RunShellCommand(command.GetData(), FileSpec(), &retcode, nullptr, 202 nullptr, std::chrono::minutes(1)); 203 if (retcode == 0) 204 return Status(); 205 // If we are here, rsync has failed - let's try the slow way before 206 // giving up 207 } 208 // open src and dst 209 // read/write, read/write, read/write, ... 210 // close src 211 // close dst 212 LLDB_LOGF(log, "[GetFile] Using block by block transfer....\n"); 213 Status error; 214 user_id_t fd_src = OpenFile(source, File::eOpenOptionReadOnly, 215 lldb::eFilePermissionsFileDefault, error); 216 217 if (fd_src == UINT64_MAX) 218 return Status::FromErrorString("unable to open source file"); 219 220 uint32_t permissions = 0; 221 error = GetFilePermissions(source, permissions); 222 223 if (permissions == 0) 224 permissions = lldb::eFilePermissionsFileDefault; 225 226 user_id_t fd_dst = FileCache::GetInstance().OpenFile( 227 destination, File::eOpenOptionCanCreate | File::eOpenOptionWriteOnly | 228 File::eOpenOptionTruncate, 229 permissions, error); 230 231 if (fd_dst == UINT64_MAX) { 232 if (error.Success()) 233 error = Status::FromErrorString("unable to open destination file"); 234 } 235 236 if (error.Success()) { 237 lldb::WritableDataBufferSP buffer_sp(new DataBufferHeap(1024, 0)); 238 uint64_t offset = 0; 239 error.Clear(); 240 while (error.Success()) { 241 const uint64_t n_read = ReadFile(fd_src, offset, buffer_sp->GetBytes(), 242 buffer_sp->GetByteSize(), error); 243 if (error.Fail()) 244 break; 245 if (n_read == 0) 246 break; 247 if (FileCache::GetInstance().WriteFile(fd_dst, offset, 248 buffer_sp->GetBytes(), n_read, 249 error) != n_read) { 250 if (!error.Fail()) 251 error = 252 Status::FromErrorString("unable to write to destination file"); 253 break; 254 } 255 offset += n_read; 256 } 257 } 258 // Ignore the close error of src. 259 if (fd_src != UINT64_MAX) 260 CloseFile(fd_src, error); 261 // And close the dst file descriptot. 262 if (fd_dst != UINT64_MAX && 263 !FileCache::GetInstance().CloseFile(fd_dst, error)) { 264 if (!error.Fail()) 265 error = Status::FromErrorString("unable to close destination file"); 266 } 267 return error; 268 } 269 return Platform::GetFile(source, destination); 270 } 271 272 std::string PlatformPOSIX::GetPlatformSpecificConnectionInformation() { 273 StreamString stream; 274 if (GetSupportsRSync()) { 275 stream.PutCString("rsync"); 276 if ((GetRSyncOpts() && *GetRSyncOpts()) || 277 (GetRSyncPrefix() && *GetRSyncPrefix()) || GetIgnoresRemoteHostname()) { 278 stream.Printf(", options: "); 279 if (GetRSyncOpts() && *GetRSyncOpts()) 280 stream.Printf("'%s' ", GetRSyncOpts()); 281 stream.Printf(", prefix: "); 282 if (GetRSyncPrefix() && *GetRSyncPrefix()) 283 stream.Printf("'%s' ", GetRSyncPrefix()); 284 if (GetIgnoresRemoteHostname()) 285 stream.Printf("ignore remote-hostname "); 286 } 287 } 288 if (GetSupportsSSH()) { 289 stream.PutCString("ssh"); 290 if (GetSSHOpts() && *GetSSHOpts()) 291 stream.Printf(", options: '%s' ", GetSSHOpts()); 292 } 293 if (GetLocalCacheDirectory() && *GetLocalCacheDirectory()) 294 stream.Printf("cache dir: %s", GetLocalCacheDirectory()); 295 if (stream.GetSize()) 296 return std::string(stream.GetString()); 297 else 298 return ""; 299 } 300 301 const lldb::UnixSignalsSP &PlatformPOSIX::GetRemoteUnixSignals() { 302 if (IsRemote() && m_remote_platform_sp) 303 return m_remote_platform_sp->GetRemoteUnixSignals(); 304 return Platform::GetRemoteUnixSignals(); 305 } 306 307 Status PlatformPOSIX::ConnectRemote(Args &args) { 308 Status error; 309 if (IsHost()) { 310 error = Status::FromErrorStringWithFormatv( 311 "can't connect to the host platform '{0}', always connected", 312 GetPluginName()); 313 } else { 314 if (!m_remote_platform_sp) 315 m_remote_platform_sp = 316 platform_gdb_server::PlatformRemoteGDBServer::CreateInstance( 317 /*force=*/true, nullptr); 318 319 if (m_remote_platform_sp && error.Success()) 320 error = m_remote_platform_sp->ConnectRemote(args); 321 else 322 error = Status::FromErrorString( 323 "failed to create a 'remote-gdb-server' platform"); 324 325 if (error.Fail()) 326 m_remote_platform_sp.reset(); 327 } 328 329 if (error.Success() && m_remote_platform_sp) { 330 if (m_option_group_platform_rsync.get() && 331 m_option_group_platform_ssh.get() && 332 m_option_group_platform_caching.get()) { 333 if (m_option_group_platform_rsync->m_rsync) { 334 SetSupportsRSync(true); 335 SetRSyncOpts(m_option_group_platform_rsync->m_rsync_opts.c_str()); 336 SetRSyncPrefix(m_option_group_platform_rsync->m_rsync_prefix.c_str()); 337 SetIgnoresRemoteHostname( 338 m_option_group_platform_rsync->m_ignores_remote_hostname); 339 } 340 if (m_option_group_platform_ssh->m_ssh) { 341 SetSupportsSSH(true); 342 SetSSHOpts(m_option_group_platform_ssh->m_ssh_opts.c_str()); 343 } 344 SetLocalCacheDirectory( 345 m_option_group_platform_caching->m_cache_dir.c_str()); 346 } 347 } 348 349 return error; 350 } 351 352 Status PlatformPOSIX::DisconnectRemote() { 353 Status error; 354 355 if (IsHost()) { 356 error = Status::FromErrorStringWithFormatv( 357 "can't disconnect from the host platform '{0}', always connected", 358 GetPluginName()); 359 } else { 360 if (m_remote_platform_sp) 361 error = m_remote_platform_sp->DisconnectRemote(); 362 else 363 error = 364 Status::FromErrorString("the platform is not currently connected"); 365 } 366 return error; 367 } 368 369 lldb::ProcessSP PlatformPOSIX::Attach(ProcessAttachInfo &attach_info, 370 Debugger &debugger, Target *target, 371 Status &error) { 372 lldb::ProcessSP process_sp; 373 Log *log = GetLog(LLDBLog::Platform); 374 375 if (IsHost()) { 376 if (target == nullptr) { 377 TargetSP new_target_sp; 378 379 error = debugger.GetTargetList().CreateTarget( 380 debugger, "", "", eLoadDependentsNo, nullptr, new_target_sp); 381 target = new_target_sp.get(); 382 LLDB_LOGF(log, "PlatformPOSIX::%s created new target", __FUNCTION__); 383 } else { 384 error.Clear(); 385 LLDB_LOGF(log, "PlatformPOSIX::%s target already existed, setting target", 386 __FUNCTION__); 387 } 388 389 if (target && error.Success()) { 390 if (log) { 391 ModuleSP exe_module_sp = target->GetExecutableModule(); 392 LLDB_LOGF(log, "PlatformPOSIX::%s set selected target to %p %s", 393 __FUNCTION__, (void *)target, 394 exe_module_sp ? exe_module_sp->GetFileSpec().GetPath().c_str() 395 : "<null>"); 396 } 397 398 process_sp = 399 target->CreateProcess(attach_info.GetListenerForProcess(debugger), 400 "gdb-remote", nullptr, true); 401 402 if (process_sp) { 403 ListenerSP listener_sp = attach_info.GetHijackListener(); 404 if (listener_sp == nullptr) { 405 listener_sp = 406 Listener::MakeListener("lldb.PlatformPOSIX.attach.hijack"); 407 attach_info.SetHijackListener(listener_sp); 408 } 409 process_sp->HijackProcessEvents(listener_sp); 410 process_sp->SetShadowListener(attach_info.GetShadowListener()); 411 error = process_sp->Attach(attach_info); 412 } 413 } 414 } else { 415 if (m_remote_platform_sp) 416 process_sp = 417 m_remote_platform_sp->Attach(attach_info, debugger, target, error); 418 else 419 error = 420 Status::FromErrorString("the platform is not currently connected"); 421 } 422 return process_sp; 423 } 424 425 lldb::ProcessSP PlatformPOSIX::DebugProcess(ProcessLaunchInfo &launch_info, 426 Debugger &debugger, Target &target, 427 Status &error) { 428 Log *log = GetLog(LLDBLog::Platform); 429 LLDB_LOG(log, "target {0}", &target); 430 431 ProcessSP process_sp; 432 433 if (!IsHost()) { 434 if (m_remote_platform_sp) 435 process_sp = m_remote_platform_sp->DebugProcess(launch_info, debugger, 436 target, error); 437 else 438 error = 439 Status::FromErrorString("the platform is not currently connected"); 440 return process_sp; 441 } 442 443 // 444 // For local debugging, we'll insist on having ProcessGDBRemote create the 445 // process. 446 // 447 448 // Make sure we stop at the entry point 449 launch_info.GetFlags().Set(eLaunchFlagDebug); 450 451 // We always launch the process we are going to debug in a separate process 452 // group, since then we can handle ^C interrupts ourselves w/o having to 453 // worry about the target getting them as well. 454 launch_info.SetLaunchInSeparateProcessGroup(true); 455 456 // Now create the gdb-remote process. 457 LLDB_LOG(log, "having target create process with gdb-remote plugin"); 458 process_sp = target.CreateProcess(launch_info.GetListener(), "gdb-remote", 459 nullptr, true); 460 461 if (!process_sp) { 462 error = Status::FromErrorString( 463 "CreateProcess() failed for gdb-remote process"); 464 LLDB_LOG(log, "error: {0}", error); 465 return process_sp; 466 } 467 468 LLDB_LOG(log, "successfully created process"); 469 470 process_sp->HijackProcessEvents(launch_info.GetHijackListener()); 471 process_sp->SetShadowListener(launch_info.GetShadowListener()); 472 473 // Log file actions. 474 if (log) { 475 LLDB_LOG(log, "launching process with the following file actions:"); 476 StreamString stream; 477 size_t i = 0; 478 const FileAction *file_action; 479 while ((file_action = launch_info.GetFileActionAtIndex(i++)) != nullptr) { 480 file_action->Dump(stream); 481 LLDB_LOG(log, "{0}", stream.GetData()); 482 stream.Clear(); 483 } 484 } 485 486 // Do the launch. 487 error = process_sp->Launch(launch_info); 488 if (error.Success()) { 489 // Hook up process PTY if we have one (which we should for local debugging 490 // with llgs). 491 int pty_fd = launch_info.GetPTY().ReleasePrimaryFileDescriptor(); 492 if (pty_fd != PseudoTerminal::invalid_fd) { 493 process_sp->SetSTDIOFileDescriptor(pty_fd); 494 LLDB_LOG(log, "hooked up STDIO pty to process"); 495 } else 496 LLDB_LOG(log, "not using process STDIO pty"); 497 } else { 498 LLDB_LOG(log, "{0}", error); 499 // FIXME figure out appropriate cleanup here. Do we delete the process? 500 // Does our caller do that? 501 } 502 503 return process_sp; 504 } 505 506 void PlatformPOSIX::CalculateTrapHandlerSymbolNames() { 507 m_trap_handlers.push_back(ConstString("_sigtramp")); 508 } 509 510 Status PlatformPOSIX::EvaluateLibdlExpression( 511 lldb_private::Process *process, const char *expr_cstr, 512 llvm::StringRef expr_prefix, lldb::ValueObjectSP &result_valobj_sp) { 513 DynamicLoader *loader = process->GetDynamicLoader(); 514 if (loader) { 515 Status error = loader->CanLoadImage(); 516 if (error.Fail()) 517 return error; 518 } 519 520 ThreadSP thread_sp(process->GetThreadList().GetExpressionExecutionThread()); 521 if (!thread_sp) 522 return Status::FromErrorString("Selected thread isn't valid"); 523 524 StackFrameSP frame_sp(thread_sp->GetStackFrameAtIndex(0)); 525 if (!frame_sp) 526 return Status::FromErrorString("Frame 0 isn't valid"); 527 528 ExecutionContext exe_ctx; 529 frame_sp->CalculateExecutionContext(exe_ctx); 530 EvaluateExpressionOptions expr_options; 531 expr_options.SetUnwindOnError(true); 532 expr_options.SetIgnoreBreakpoints(true); 533 expr_options.SetExecutionPolicy(eExecutionPolicyAlways); 534 expr_options.SetLanguage(eLanguageTypeC_plus_plus); 535 expr_options.SetTrapExceptions(false); // dlopen can't throw exceptions, so 536 // don't do the work to trap them. 537 expr_options.SetTimeout(process->GetUtilityExpressionTimeout()); 538 539 ExpressionResults result = UserExpression::Evaluate( 540 exe_ctx, expr_options, expr_cstr, expr_prefix, result_valobj_sp); 541 if (result != eExpressionCompleted) 542 return result_valobj_sp ? result_valobj_sp->GetError().Clone() 543 : Status("unknown error"); 544 545 if (result_valobj_sp->GetError().Fail()) 546 return result_valobj_sp->GetError().Clone(); 547 return Status(); 548 } 549 550 std::unique_ptr<UtilityFunction> 551 PlatformPOSIX::MakeLoadImageUtilityFunction(ExecutionContext &exe_ctx, 552 Status &error) { 553 // Remember to prepend this with the prefix from 554 // GetLibdlFunctionDeclarations. The returned values are all in 555 // __lldb_dlopen_result for consistency. The wrapper returns a void * but 556 // doesn't use it because UtilityFunctions don't work with void returns at 557 // present. 558 // 559 // Use lazy binding so as to not make dlopen()'s success conditional on 560 // forcing every symbol in the library. 561 // 562 // In general, the debugger should allow programs to load & run with 563 // libraries as far as they can, instead of defaulting to being super-picky 564 // about unavailable symbols. 565 // 566 // The value "1" appears to imply lazy binding (RTLD_LAZY) on both Darwin 567 // and other POSIX OSes. 568 static const char *dlopen_wrapper_code = R"( 569 const int RTLD_LAZY = 1; 570 571 struct __lldb_dlopen_result { 572 void *image_ptr; 573 const char *error_str; 574 }; 575 576 extern "C" void *memcpy(void *, const void *, size_t size); 577 extern "C" size_t strlen(const char *); 578 579 580 void * __lldb_dlopen_wrapper (const char *name, 581 const char *path_strings, 582 char *buffer, 583 __lldb_dlopen_result *result_ptr) 584 { 585 // This is the case where the name is the full path: 586 if (!path_strings) { 587 result_ptr->image_ptr = dlopen(name, RTLD_LAZY); 588 if (result_ptr->image_ptr) 589 result_ptr->error_str = nullptr; 590 else 591 result_ptr->error_str = dlerror(); 592 return nullptr; 593 } 594 595 // This is the case where we have a list of paths: 596 size_t name_len = strlen(name); 597 while (path_strings && path_strings[0] != '\0') { 598 size_t path_len = strlen(path_strings); 599 memcpy((void *) buffer, (void *) path_strings, path_len); 600 buffer[path_len] = '/'; 601 char *target_ptr = buffer+path_len+1; 602 memcpy((void *) target_ptr, (void *) name, name_len + 1); 603 result_ptr->image_ptr = dlopen(buffer, RTLD_LAZY); 604 if (result_ptr->image_ptr) { 605 result_ptr->error_str = nullptr; 606 break; 607 } 608 result_ptr->error_str = dlerror(); 609 path_strings = path_strings + path_len + 1; 610 } 611 return nullptr; 612 } 613 )"; 614 615 static const char *dlopen_wrapper_name = "__lldb_dlopen_wrapper"; 616 Process *process = exe_ctx.GetProcessSP().get(); 617 // Insert the dlopen shim defines into our generic expression: 618 std::string expr(std::string(GetLibdlFunctionDeclarations(process))); 619 expr.append(dlopen_wrapper_code); 620 Status utility_error; 621 DiagnosticManager diagnostics; 622 623 auto utility_fn_or_error = process->GetTarget().CreateUtilityFunction( 624 std::move(expr), dlopen_wrapper_name, eLanguageTypeC_plus_plus, exe_ctx); 625 if (!utility_fn_or_error) { 626 std::string error_str = llvm::toString(utility_fn_or_error.takeError()); 627 error = Status::FromErrorStringWithFormat( 628 "dlopen error: could not create utility function: %s", 629 error_str.c_str()); 630 return nullptr; 631 } 632 std::unique_ptr<UtilityFunction> dlopen_utility_func_up = 633 std::move(*utility_fn_or_error); 634 635 Value value; 636 ValueList arguments; 637 FunctionCaller *do_dlopen_function = nullptr; 638 639 // Fetch the clang types we will need: 640 TypeSystemClangSP scratch_ts_sp = 641 ScratchTypeSystemClang::GetForTarget(process->GetTarget()); 642 if (!scratch_ts_sp) 643 return nullptr; 644 645 CompilerType clang_void_pointer_type = 646 scratch_ts_sp->GetBasicType(eBasicTypeVoid).GetPointerType(); 647 CompilerType clang_char_pointer_type = 648 scratch_ts_sp->GetBasicType(eBasicTypeChar).GetPointerType(); 649 650 // We are passing four arguments, the basename, the list of places to look, 651 // a buffer big enough for all the path + name combos, and 652 // a pointer to the storage we've made for the result: 653 value.SetValueType(Value::ValueType::Scalar); 654 value.SetCompilerType(clang_void_pointer_type); 655 arguments.PushValue(value); 656 value.SetCompilerType(clang_char_pointer_type); 657 arguments.PushValue(value); 658 arguments.PushValue(value); 659 arguments.PushValue(value); 660 661 do_dlopen_function = dlopen_utility_func_up->MakeFunctionCaller( 662 clang_void_pointer_type, arguments, exe_ctx.GetThreadSP(), utility_error); 663 if (utility_error.Fail()) { 664 error = Status::FromErrorStringWithFormat( 665 "dlopen error: could not make function caller: %s", 666 utility_error.AsCString()); 667 return nullptr; 668 } 669 670 do_dlopen_function = dlopen_utility_func_up->GetFunctionCaller(); 671 if (!do_dlopen_function) { 672 error = 673 Status::FromErrorString("dlopen error: could not get function caller."); 674 return nullptr; 675 } 676 677 // We made a good utility function, so cache it in the process: 678 return dlopen_utility_func_up; 679 } 680 681 uint32_t PlatformPOSIX::DoLoadImage(lldb_private::Process *process, 682 const lldb_private::FileSpec &remote_file, 683 const std::vector<std::string> *paths, 684 lldb_private::Status &error, 685 lldb_private::FileSpec *loaded_image) { 686 if (loaded_image) 687 loaded_image->Clear(); 688 689 std::string path; 690 path = remote_file.GetPath(false); 691 692 ThreadSP thread_sp = process->GetThreadList().GetExpressionExecutionThread(); 693 if (!thread_sp) { 694 error = Status::FromErrorString( 695 "dlopen error: no thread available to call dlopen."); 696 return LLDB_INVALID_IMAGE_TOKEN; 697 } 698 699 DiagnosticManager diagnostics; 700 701 ExecutionContext exe_ctx; 702 thread_sp->CalculateExecutionContext(exe_ctx); 703 704 Status utility_error; 705 UtilityFunction *dlopen_utility_func; 706 ValueList arguments; 707 FunctionCaller *do_dlopen_function = nullptr; 708 709 // The UtilityFunction is held in the Process. Platforms don't track the 710 // lifespan of the Targets that use them, we can't put this in the Platform. 711 dlopen_utility_func = process->GetLoadImageUtilityFunction( 712 this, [&]() -> std::unique_ptr<UtilityFunction> { 713 return MakeLoadImageUtilityFunction(exe_ctx, error); 714 }); 715 // If we couldn't make it, the error will be in error, so we can exit here. 716 if (!dlopen_utility_func) 717 return LLDB_INVALID_IMAGE_TOKEN; 718 719 do_dlopen_function = dlopen_utility_func->GetFunctionCaller(); 720 if (!do_dlopen_function) { 721 error = 722 Status::FromErrorString("dlopen error: could not get function caller."); 723 return LLDB_INVALID_IMAGE_TOKEN; 724 } 725 arguments = do_dlopen_function->GetArgumentValues(); 726 727 // Now insert the path we are searching for and the result structure into the 728 // target. 729 uint32_t permissions = ePermissionsReadable|ePermissionsWritable; 730 size_t path_len = path.size() + 1; 731 lldb::addr_t path_addr = process->AllocateMemory(path_len, 732 permissions, 733 utility_error); 734 if (path_addr == LLDB_INVALID_ADDRESS) { 735 error = Status::FromErrorStringWithFormat( 736 "dlopen error: could not allocate memory for path: %s", 737 utility_error.AsCString()); 738 return LLDB_INVALID_IMAGE_TOKEN; 739 } 740 741 // Make sure we deallocate the input string memory: 742 auto path_cleanup = llvm::make_scope_exit([process, path_addr] { 743 // Deallocate the buffer. 744 process->DeallocateMemory(path_addr); 745 }); 746 747 process->WriteMemory(path_addr, path.c_str(), path_len, utility_error); 748 if (utility_error.Fail()) { 749 error = Status::FromErrorStringWithFormat( 750 "dlopen error: could not write path string: %s", 751 utility_error.AsCString()); 752 return LLDB_INVALID_IMAGE_TOKEN; 753 } 754 755 // Make space for our return structure. It is two pointers big: the token 756 // and the error string. 757 const uint32_t addr_size = process->GetAddressByteSize(); 758 lldb::addr_t return_addr = process->CallocateMemory(2*addr_size, 759 permissions, 760 utility_error); 761 if (utility_error.Fail()) { 762 error = Status::FromErrorStringWithFormat( 763 "dlopen error: could not allocate memory for path: %s", 764 utility_error.AsCString()); 765 return LLDB_INVALID_IMAGE_TOKEN; 766 } 767 768 // Make sure we deallocate the result structure memory 769 auto return_cleanup = llvm::make_scope_exit([process, return_addr] { 770 // Deallocate the buffer 771 process->DeallocateMemory(return_addr); 772 }); 773 774 // This will be the address of the storage for paths, if we are using them, 775 // or nullptr to signal we aren't. 776 lldb::addr_t path_array_addr = 0x0; 777 std::optional<llvm::detail::scope_exit<std::function<void()>>> 778 path_array_cleanup; 779 780 // This is the address to a buffer large enough to hold the largest path 781 // conjoined with the library name we're passing in. This is a convenience 782 // to avoid having to call malloc in the dlopen function. 783 lldb::addr_t buffer_addr = 0x0; 784 std::optional<llvm::detail::scope_exit<std::function<void()>>> buffer_cleanup; 785 786 // Set the values into our args and write them to the target: 787 if (paths != nullptr) { 788 // First insert the paths into the target. This is expected to be a 789 // continuous buffer with the strings laid out null terminated and 790 // end to end with an empty string terminating the buffer. 791 // We also compute the buffer's required size as we go. 792 size_t buffer_size = 0; 793 std::string path_array; 794 for (auto path : *paths) { 795 // Don't insert empty paths, they will make us abort the path 796 // search prematurely. 797 if (path.empty()) 798 continue; 799 size_t path_size = path.size(); 800 path_array.append(path); 801 path_array.push_back('\0'); 802 if (path_size > buffer_size) 803 buffer_size = path_size; 804 } 805 path_array.push_back('\0'); 806 807 path_array_addr = process->AllocateMemory(path_array.size(), 808 permissions, 809 utility_error); 810 if (path_array_addr == LLDB_INVALID_ADDRESS) { 811 error = Status::FromErrorStringWithFormat( 812 "dlopen error: could not allocate memory for path array: %s", 813 utility_error.AsCString()); 814 return LLDB_INVALID_IMAGE_TOKEN; 815 } 816 817 // Make sure we deallocate the paths array. 818 path_array_cleanup.emplace([process, path_array_addr]() { 819 // Deallocate the path array. 820 process->DeallocateMemory(path_array_addr); 821 }); 822 823 process->WriteMemory(path_array_addr, path_array.data(), 824 path_array.size(), utility_error); 825 826 if (utility_error.Fail()) { 827 error = Status::FromErrorStringWithFormat( 828 "dlopen error: could not write path array: %s", 829 utility_error.AsCString()); 830 return LLDB_INVALID_IMAGE_TOKEN; 831 } 832 // Now make spaces in the target for the buffer. We need to add one for 833 // the '/' that the utility function will insert and one for the '\0': 834 buffer_size += path.size() + 2; 835 836 buffer_addr = process->AllocateMemory(buffer_size, 837 permissions, 838 utility_error); 839 if (buffer_addr == LLDB_INVALID_ADDRESS) { 840 error = Status::FromErrorStringWithFormat( 841 "dlopen error: could not allocate memory for buffer: %s", 842 utility_error.AsCString()); 843 return LLDB_INVALID_IMAGE_TOKEN; 844 } 845 846 // Make sure we deallocate the buffer memory: 847 buffer_cleanup.emplace([process, buffer_addr]() { 848 // Deallocate the buffer. 849 process->DeallocateMemory(buffer_addr); 850 }); 851 } 852 853 arguments.GetValueAtIndex(0)->GetScalar() = path_addr; 854 arguments.GetValueAtIndex(1)->GetScalar() = path_array_addr; 855 arguments.GetValueAtIndex(2)->GetScalar() = buffer_addr; 856 arguments.GetValueAtIndex(3)->GetScalar() = return_addr; 857 858 lldb::addr_t func_args_addr = LLDB_INVALID_ADDRESS; 859 860 diagnostics.Clear(); 861 if (!do_dlopen_function->WriteFunctionArguments(exe_ctx, 862 func_args_addr, 863 arguments, 864 diagnostics)) { 865 error = Status::FromError(diagnostics.GetAsError( 866 lldb::eExpressionSetupError, 867 "dlopen error: could not write function arguments:")); 868 return LLDB_INVALID_IMAGE_TOKEN; 869 } 870 871 // Make sure we clean up the args structure. We can't reuse it because the 872 // Platform lives longer than the process and the Platforms don't get a 873 // signal to clean up cached data when a process goes away. 874 auto args_cleanup = 875 llvm::make_scope_exit([do_dlopen_function, &exe_ctx, func_args_addr] { 876 do_dlopen_function->DeallocateFunctionResults(exe_ctx, func_args_addr); 877 }); 878 879 // Now run the caller: 880 EvaluateExpressionOptions options; 881 options.SetExecutionPolicy(eExecutionPolicyAlways); 882 options.SetLanguage(eLanguageTypeC_plus_plus); 883 options.SetIgnoreBreakpoints(true); 884 options.SetUnwindOnError(true); 885 options.SetTrapExceptions(false); // dlopen can't throw exceptions, so 886 // don't do the work to trap them. 887 options.SetTimeout(process->GetUtilityExpressionTimeout()); 888 options.SetIsForUtilityExpr(true); 889 890 Value return_value; 891 // Fetch the clang types we will need: 892 TypeSystemClangSP scratch_ts_sp = 893 ScratchTypeSystemClang::GetForTarget(process->GetTarget()); 894 if (!scratch_ts_sp) { 895 error = 896 Status::FromErrorString("dlopen error: Unable to get TypeSystemClang"); 897 return LLDB_INVALID_IMAGE_TOKEN; 898 } 899 900 CompilerType clang_void_pointer_type = 901 scratch_ts_sp->GetBasicType(eBasicTypeVoid).GetPointerType(); 902 903 return_value.SetCompilerType(clang_void_pointer_type); 904 905 ExpressionResults results = do_dlopen_function->ExecuteFunction( 906 exe_ctx, &func_args_addr, options, diagnostics, return_value); 907 if (results != eExpressionCompleted) { 908 error = Status::FromError(diagnostics.GetAsError( 909 lldb::eExpressionSetupError, 910 "dlopen error: failed executing dlopen wrapper function:")); 911 return LLDB_INVALID_IMAGE_TOKEN; 912 } 913 914 // Read the dlopen token from the return area: 915 lldb::addr_t token = process->ReadPointerFromMemory(return_addr, 916 utility_error); 917 if (utility_error.Fail()) { 918 error = Status::FromErrorStringWithFormat( 919 "dlopen error: could not read the return struct: %s", 920 utility_error.AsCString()); 921 return LLDB_INVALID_IMAGE_TOKEN; 922 } 923 924 // The dlopen succeeded! 925 if (token != 0x0) { 926 if (loaded_image && buffer_addr != 0x0) 927 { 928 // Capture the image which was loaded. We leave it in the buffer on 929 // exit from the dlopen function, so we can just read it from there: 930 std::string name_string; 931 process->ReadCStringFromMemory(buffer_addr, name_string, utility_error); 932 if (utility_error.Success()) 933 loaded_image->SetFile(name_string, llvm::sys::path::Style::posix); 934 } 935 return process->AddImageToken(token); 936 } 937 938 // We got an error, lets read in the error string: 939 std::string dlopen_error_str; 940 lldb::addr_t error_addr 941 = process->ReadPointerFromMemory(return_addr + addr_size, utility_error); 942 if (utility_error.Fail()) { 943 error = Status::FromErrorStringWithFormat( 944 "dlopen error: could not read error string: %s", 945 utility_error.AsCString()); 946 return LLDB_INVALID_IMAGE_TOKEN; 947 } 948 949 size_t num_chars = process->ReadCStringFromMemory(error_addr + addr_size, 950 dlopen_error_str, 951 utility_error); 952 if (utility_error.Success() && num_chars > 0) 953 error = Status::FromErrorStringWithFormat("dlopen error: %s", 954 dlopen_error_str.c_str()); 955 else 956 error = 957 Status::FromErrorStringWithFormat("dlopen failed for unknown reasons."); 958 959 return LLDB_INVALID_IMAGE_TOKEN; 960 } 961 962 Status PlatformPOSIX::UnloadImage(lldb_private::Process *process, 963 uint32_t image_token) { 964 const addr_t image_addr = process->GetImagePtrFromToken(image_token); 965 if (image_addr == LLDB_INVALID_IMAGE_TOKEN) 966 return Status::FromErrorString("Invalid image token"); 967 968 StreamString expr; 969 expr.Printf("dlclose((void *)0x%" PRIx64 ")", image_addr); 970 llvm::StringRef prefix = GetLibdlFunctionDeclarations(process); 971 lldb::ValueObjectSP result_valobj_sp; 972 Status error = EvaluateLibdlExpression(process, expr.GetData(), prefix, 973 result_valobj_sp); 974 if (error.Fail()) 975 return error; 976 977 if (result_valobj_sp->GetError().Fail()) 978 return result_valobj_sp->GetError().Clone(); 979 980 Scalar scalar; 981 if (result_valobj_sp->ResolveValue(scalar)) { 982 if (scalar.UInt(1)) 983 return Status::FromErrorStringWithFormat("expression failed: \"%s\"", 984 expr.GetData()); 985 process->ResetImageToken(image_token); 986 } 987 return Status(); 988 } 989 990 llvm::StringRef 991 PlatformPOSIX::GetLibdlFunctionDeclarations(lldb_private::Process *process) { 992 return R"( 993 extern "C" void* dlopen(const char*, int); 994 extern "C" void* dlsym(void*, const char*); 995 extern "C" int dlclose(void*); 996 extern "C" char* dlerror(void); 997 )"; 998 } 999 1000 ConstString PlatformPOSIX::GetFullNameForDylib(ConstString basename) { 1001 if (basename.IsEmpty()) 1002 return basename; 1003 1004 StreamString stream; 1005 stream.Printf("lib%s.so", basename.GetCString()); 1006 return ConstString(stream.GetString()); 1007 } 1008