1 //===-- CommandObjectExpression.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 // C Includes 11 // C++ Includes 12 // Other libraries and framework includes 13 #include "llvm/ADT/STLExtras.h" 14 #include "llvm/ADT/StringRef.h" 15 16 // Project includes 17 #include "CommandObjectExpression.h" 18 #include "lldb/Core/Value.h" 19 #include "lldb/Core/ValueObjectVariable.h" 20 #include "lldb/DataFormatters/ValueObjectPrinter.h" 21 #include "Plugins/ExpressionParser/Clang/ClangExpressionVariable.h" 22 #include "lldb/Expression/UserExpression.h" 23 #include "lldb/Expression/DWARFExpression.h" 24 #include "lldb/Expression/REPL.h" 25 #include "lldb/Host/Host.h" 26 #include "lldb/Host/StringConvert.h" 27 #include "lldb/Core/Debugger.h" 28 #include "lldb/Interpreter/CommandInterpreter.h" 29 #include "lldb/Interpreter/CommandReturnObject.h" 30 #include "lldb/Target/Language.h" 31 #include "lldb/Symbol/ObjectFile.h" 32 #include "lldb/Symbol/Variable.h" 33 #include "lldb/Target/Process.h" 34 #include "lldb/Target/StackFrame.h" 35 #include "lldb/Target/Target.h" 36 #include "lldb/Target/Thread.h" 37 38 using namespace lldb; 39 using namespace lldb_private; 40 41 CommandObjectExpression::CommandOptions::CommandOptions () : 42 OptionGroup() 43 { 44 } 45 46 CommandObjectExpression::CommandOptions::~CommandOptions() = default; 47 48 static OptionEnumValueElement g_description_verbosity_type[] = 49 { 50 { eLanguageRuntimeDescriptionDisplayVerbosityCompact, "compact", "Only show the description string"}, 51 { eLanguageRuntimeDescriptionDisplayVerbosityFull, "full", "Show the full output, including persistent variable's name and type"}, 52 { 0, nullptr, nullptr } 53 }; 54 55 OptionDefinition 56 CommandObjectExpression::CommandOptions::g_option_table[] = 57 { 58 { LLDB_OPT_SET_1 | LLDB_OPT_SET_2, false, "all-threads", 'a', OptionParser::eRequiredArgument, nullptr, nullptr, 0, eArgTypeBoolean, "Should we run all threads if the execution doesn't complete on one thread."}, 59 { LLDB_OPT_SET_1 | LLDB_OPT_SET_2, false, "ignore-breakpoints", 'i', OptionParser::eRequiredArgument, nullptr, nullptr, 0, eArgTypeBoolean, "Ignore breakpoint hits while running expressions"}, 60 { LLDB_OPT_SET_1 | LLDB_OPT_SET_2, false, "timeout", 't', OptionParser::eRequiredArgument, nullptr, nullptr, 0, eArgTypeUnsignedInteger, "Timeout value (in microseconds) for running the expression."}, 61 { LLDB_OPT_SET_1 | LLDB_OPT_SET_2, false, "unwind-on-error", 'u', OptionParser::eRequiredArgument, nullptr, nullptr, 0, eArgTypeBoolean, "Clean up program state if the expression causes a crash, or raises a signal. Note, unlike gdb hitting a breakpoint is controlled by another option (-i)."}, 62 { LLDB_OPT_SET_1 | LLDB_OPT_SET_2, false, "debug", 'g', OptionParser::eNoArgument , nullptr, nullptr, 0, eArgTypeNone, "When specified, debug the JIT code by setting a breakpoint on the first instruction and forcing breakpoints to not be ignored (-i0) and no unwinding to happen on error (-u0)."}, 63 { LLDB_OPT_SET_1 | LLDB_OPT_SET_2, false, "language", 'l', OptionParser::eRequiredArgument, nullptr, nullptr, 0, eArgTypeLanguage, "Specifies the Language to use when parsing the expression. If not set the target.language setting is used." }, 64 { LLDB_OPT_SET_1 | LLDB_OPT_SET_2, false, "apply-fixits", 'X', OptionParser::eRequiredArgument, nullptr, nullptr, 0, eArgTypeLanguage, "If true, simple FixIt hints will be automatically applied to the expression." }, 65 { LLDB_OPT_SET_1, false, "description-verbosity", 'v', OptionParser::eOptionalArgument, nullptr, g_description_verbosity_type, 0, eArgTypeDescriptionVerbosity, "How verbose should the output of this expression be, if the object description is asked for."}, 66 }; 67 68 uint32_t 69 CommandObjectExpression::CommandOptions::GetNumDefinitions () 70 { 71 return llvm::array_lengthof(g_option_table); 72 } 73 74 Error 75 CommandObjectExpression::CommandOptions::SetOptionValue (CommandInterpreter &interpreter, 76 uint32_t option_idx, 77 const char *option_arg) 78 { 79 Error error; 80 81 const int short_option = g_option_table[option_idx].short_option; 82 83 switch (short_option) 84 { 85 case 'l': 86 language = Language::GetLanguageTypeFromString (option_arg); 87 if (language == eLanguageTypeUnknown) 88 error.SetErrorStringWithFormat ("unknown language type: '%s' for expression", option_arg); 89 break; 90 91 case 'a': 92 { 93 bool success; 94 bool result; 95 result = Args::StringToBoolean(option_arg, true, &success); 96 if (!success) 97 error.SetErrorStringWithFormat("invalid all-threads value setting: \"%s\"", option_arg); 98 else 99 try_all_threads = result; 100 } 101 break; 102 103 case 'i': 104 { 105 bool success; 106 bool tmp_value = Args::StringToBoolean(option_arg, true, &success); 107 if (success) 108 ignore_breakpoints = tmp_value; 109 else 110 error.SetErrorStringWithFormat("could not convert \"%s\" to a boolean value.", option_arg); 111 break; 112 } 113 case 't': 114 { 115 bool success; 116 uint32_t result; 117 result = StringConvert::ToUInt32(option_arg, 0, 0, &success); 118 if (success) 119 timeout = result; 120 else 121 error.SetErrorStringWithFormat ("invalid timeout setting \"%s\"", option_arg); 122 } 123 break; 124 125 case 'u': 126 { 127 bool success; 128 bool tmp_value = Args::StringToBoolean(option_arg, true, &success); 129 if (success) 130 unwind_on_error = tmp_value; 131 else 132 error.SetErrorStringWithFormat("could not convert \"%s\" to a boolean value.", option_arg); 133 break; 134 } 135 136 case 'v': 137 if (!option_arg) 138 { 139 m_verbosity = eLanguageRuntimeDescriptionDisplayVerbosityFull; 140 break; 141 } 142 m_verbosity = (LanguageRuntimeDescriptionDisplayVerbosity) Args::StringToOptionEnum(option_arg, g_option_table[option_idx].enum_values, 0, error); 143 if (!error.Success()) 144 error.SetErrorStringWithFormat ("unrecognized value for description-verbosity '%s'", option_arg); 145 break; 146 147 case 'g': 148 debug = true; 149 unwind_on_error = false; 150 ignore_breakpoints = false; 151 break; 152 153 case 'X': 154 { 155 bool success; 156 bool tmp_value = Args::StringToBoolean(option_arg, true, &success); 157 if (success) 158 auto_apply_fixits = tmp_value ? eLazyBoolYes : eLazyBoolNo; 159 else 160 error.SetErrorStringWithFormat("could not convert \"%s\" to a boolean value.", option_arg); 161 break; 162 } 163 164 default: 165 error.SetErrorStringWithFormat("invalid short option character '%c'", short_option); 166 break; 167 } 168 169 return error; 170 } 171 172 void 173 CommandObjectExpression::CommandOptions::OptionParsingStarting (CommandInterpreter &interpreter) 174 { 175 Process *process = interpreter.GetExecutionContext().GetProcessPtr(); 176 if (process != nullptr) 177 { 178 ignore_breakpoints = process->GetIgnoreBreakpointsInExpressions(); 179 unwind_on_error = process->GetUnwindOnErrorInExpressions(); 180 } 181 else 182 { 183 ignore_breakpoints = true; 184 unwind_on_error = true; 185 } 186 187 show_summary = true; 188 try_all_threads = true; 189 timeout = 0; 190 debug = false; 191 language = eLanguageTypeUnknown; 192 m_verbosity = eLanguageRuntimeDescriptionDisplayVerbosityCompact; 193 auto_apply_fixits = eLazyBoolCalculate; 194 } 195 196 const OptionDefinition* 197 CommandObjectExpression::CommandOptions::GetDefinitions () 198 { 199 return g_option_table; 200 } 201 202 CommandObjectExpression::CommandObjectExpression (CommandInterpreter &interpreter) : 203 CommandObjectRaw(interpreter, 204 "expression", 205 "Evaluate an expression in the current program context, using user defined variables and variables currently in scope.", 206 nullptr, 207 eCommandProcessMustBePaused | eCommandTryTargetAPILock), 208 IOHandlerDelegate (IOHandlerDelegate::Completion::Expression), 209 m_option_group (interpreter), 210 m_format_options (eFormatDefault), 211 m_repl_option (LLDB_OPT_SET_1, false, "repl", 'r', "Drop into REPL", false, true), 212 m_command_options (), 213 m_expr_line_count (0), 214 m_expr_lines () 215 { 216 SetHelpLong( 217 R"( 218 Timeouts: 219 220 )" " If the expression can be evaluated statically (without running code) then it will be. \ 221 Otherwise, by default the expression will run on the current thread with a short timeout: \ 222 currently .25 seconds. If it doesn't return in that time, the evaluation will be interrupted \ 223 and resumed with all threads running. You can use the -a option to disable retrying on all \ 224 threads. You can use the -t option to set a shorter timeout." R"( 225 226 User defined variables: 227 228 )" " You can define your own variables for convenience or to be used in subsequent expressions. \ 229 You define them the same way you would define variables in C. If the first character of \ 230 your user defined variable is a $, then the variable's value will be available in future \ 231 expressions, otherwise it will just be available in the current expression." R"( 232 233 Continuing evaluation after a breakpoint: 234 235 )" " If the \"-i false\" option is used, and execution is interrupted by a breakpoint hit, once \ 236 you are done with your investigation, you can either remove the expression execution frames \ 237 from the stack with \"thread return -x\" or if you are still interested in the expression result \ 238 you can issue the \"continue\" command and the expression evaluation will complete and the \ 239 expression result will be available using the \"thread.completed-expression\" key in the thread \ 240 format." R"( 241 242 Examples: 243 244 expr my_struct->a = my_array[3] 245 expr -f bin -- (index * 8) + 5 246 expr unsigned int $foo = 5 247 expr char c[] = \"foo\"; c[0])" 248 ); 249 250 CommandArgumentEntry arg; 251 CommandArgumentData expression_arg; 252 253 // Define the first (and only) variant of this arg. 254 expression_arg.arg_type = eArgTypeExpression; 255 expression_arg.arg_repetition = eArgRepeatPlain; 256 257 // There is only one variant this argument could be; put it into the argument entry. 258 arg.push_back (expression_arg); 259 260 // Push the data for the first argument into the m_arguments vector. 261 m_arguments.push_back (arg); 262 263 // Add the "--format" and "--gdb-format" 264 m_option_group.Append (&m_format_options, OptionGroupFormat::OPTION_GROUP_FORMAT | OptionGroupFormat::OPTION_GROUP_GDB_FMT, LLDB_OPT_SET_1); 265 m_option_group.Append (&m_command_options); 266 m_option_group.Append (&m_varobj_options, LLDB_OPT_SET_ALL, LLDB_OPT_SET_1 | LLDB_OPT_SET_2); 267 m_option_group.Append (&m_repl_option, LLDB_OPT_SET_ALL, LLDB_OPT_SET_3); 268 m_option_group.Finalize(); 269 } 270 271 CommandObjectExpression::~CommandObjectExpression() = default; 272 273 Options * 274 CommandObjectExpression::GetOptions () 275 { 276 return &m_option_group; 277 } 278 279 bool 280 CommandObjectExpression::EvaluateExpression(const char *expr, 281 Stream *output_stream, 282 Stream *error_stream, 283 CommandReturnObject *result) 284 { 285 // Don't use m_exe_ctx as this might be called asynchronously 286 // after the command object DoExecute has finished when doing 287 // multi-line expression that use an input reader... 288 ExecutionContext exe_ctx (m_interpreter.GetExecutionContext()); 289 290 Target *target = exe_ctx.GetTargetPtr(); 291 292 if (!target) 293 target = GetDummyTarget(); 294 295 if (target) 296 { 297 lldb::ValueObjectSP result_valobj_sp; 298 bool keep_in_memory = true; 299 StackFrame *frame = exe_ctx.GetFramePtr(); 300 301 EvaluateExpressionOptions options; 302 options.SetCoerceToId(m_varobj_options.use_objc); 303 options.SetUnwindOnError(m_command_options.unwind_on_error); 304 options.SetIgnoreBreakpoints (m_command_options.ignore_breakpoints); 305 options.SetKeepInMemory(keep_in_memory); 306 options.SetUseDynamic(m_varobj_options.use_dynamic); 307 options.SetTryAllThreads(m_command_options.try_all_threads); 308 options.SetDebug(m_command_options.debug); 309 options.SetLanguage(m_command_options.language); 310 311 bool auto_apply_fixits; 312 if (m_command_options.auto_apply_fixits == eLazyBoolCalculate) 313 auto_apply_fixits = target->GetEnableAutoApplyFixIts(); 314 else 315 auto_apply_fixits = m_command_options.auto_apply_fixits == eLazyBoolYes ? true : false; 316 317 options.SetAutoApplyFixIts(auto_apply_fixits); 318 319 // If there is any chance we are going to stop and want to see 320 // what went wrong with our expression, we should generate debug info 321 if (!m_command_options.ignore_breakpoints || 322 !m_command_options.unwind_on_error) 323 options.SetGenerateDebugInfo(true); 324 325 if (m_command_options.timeout > 0) 326 options.SetTimeoutUsec(m_command_options.timeout); 327 else 328 options.SetTimeoutUsec(0); 329 330 target->EvaluateExpression(expr, frame, result_valobj_sp, options); 331 332 if (result_valobj_sp) 333 { 334 Format format = m_format_options.GetFormat(); 335 336 if (result_valobj_sp->GetError().Success()) 337 { 338 if (format != eFormatVoid) 339 { 340 if (format != eFormatDefault) 341 result_valobj_sp->SetFormat (format); 342 343 DumpValueObjectOptions options(m_varobj_options.GetAsDumpOptions(m_command_options.m_verbosity,format)); 344 options.SetVariableFormatDisplayLanguage(result_valobj_sp->GetPreferredDisplayLanguage()); 345 346 result_valobj_sp->Dump(*output_stream,options); 347 348 if (result) 349 result->SetStatus (eReturnStatusSuccessFinishResult); 350 } 351 } 352 else 353 { 354 if (result_valobj_sp->GetError().GetError() == UserExpression::kNoResult) 355 { 356 if (format != eFormatVoid && m_interpreter.GetDebugger().GetNotifyVoid()) 357 { 358 error_stream->PutCString("(void)\n"); 359 } 360 361 if (result) 362 result->SetStatus (eReturnStatusSuccessFinishResult); 363 } 364 else 365 { 366 const char *error_cstr = result_valobj_sp->GetError().AsCString(); 367 if (error_cstr && error_cstr[0]) 368 { 369 const size_t error_cstr_len = strlen (error_cstr); 370 const bool ends_with_newline = error_cstr[error_cstr_len - 1] == '\n'; 371 if (strstr(error_cstr, "error:") != error_cstr) 372 error_stream->PutCString ("error: "); 373 error_stream->Write(error_cstr, error_cstr_len); 374 if (!ends_with_newline) 375 error_stream->EOL(); 376 } 377 else 378 { 379 error_stream->PutCString ("error: unknown error\n"); 380 } 381 382 if (result) 383 result->SetStatus (eReturnStatusFailed); 384 } 385 } 386 } 387 } 388 else 389 { 390 error_stream->Printf ("error: invalid execution context for expression\n"); 391 return false; 392 } 393 394 return true; 395 } 396 397 void 398 CommandObjectExpression::IOHandlerInputComplete (IOHandler &io_handler, std::string &line) 399 { 400 io_handler.SetIsDone(true); 401 // StreamSP output_stream = io_handler.GetDebugger().GetAsyncOutputStream(); 402 // StreamSP error_stream = io_handler.GetDebugger().GetAsyncErrorStream(); 403 StreamFileSP output_sp(io_handler.GetOutputStreamFile()); 404 StreamFileSP error_sp(io_handler.GetErrorStreamFile()); 405 406 EvaluateExpression (line.c_str(), 407 output_sp.get(), 408 error_sp.get()); 409 if (output_sp) 410 output_sp->Flush(); 411 if (error_sp) 412 error_sp->Flush(); 413 } 414 415 LineStatus 416 CommandObjectExpression::IOHandlerLinesUpdated (IOHandler &io_handler, 417 StringList &lines, 418 uint32_t line_idx, 419 Error &error) 420 { 421 if (line_idx == UINT32_MAX) 422 { 423 // Remove the last line from "lines" so it doesn't appear 424 // in our final expression 425 lines.PopBack(); 426 error.Clear(); 427 return LineStatus::Done; 428 } 429 else if (line_idx + 1 == lines.GetSize()) 430 { 431 // The last line was edited, if this line is empty, then we are done 432 // getting our multiple lines. 433 if (lines[line_idx].empty()) 434 return LineStatus::Done; 435 } 436 return LineStatus::Success; 437 } 438 439 void 440 CommandObjectExpression::GetMultilineExpression () 441 { 442 m_expr_lines.clear(); 443 m_expr_line_count = 0; 444 445 Debugger &debugger = GetCommandInterpreter().GetDebugger(); 446 bool color_prompt = debugger.GetUseColor(); 447 const bool multiple_lines = true; // Get multiple lines 448 IOHandlerSP io_handler_sp(new IOHandlerEditline(debugger, 449 IOHandler::Type::Expression, 450 "lldb-expr", // Name of input reader for history 451 nullptr, // No prompt 452 nullptr, // Continuation prompt 453 multiple_lines, 454 color_prompt, 455 1, // Show line numbers starting at 1 456 *this)); 457 458 StreamFileSP output_sp(io_handler_sp->GetOutputStreamFile()); 459 if (output_sp) 460 { 461 output_sp->PutCString("Enter expressions, then terminate with an empty line to evaluate:\n"); 462 output_sp->Flush(); 463 } 464 debugger.PushIOHandler(io_handler_sp); 465 } 466 467 bool 468 CommandObjectExpression::DoExecute(const char *command, 469 CommandReturnObject &result) 470 { 471 m_option_group.NotifyOptionParsingStarting(); 472 473 const char * expr = nullptr; 474 475 if (command[0] == '\0') 476 { 477 GetMultilineExpression (); 478 return result.Succeeded(); 479 } 480 481 if (command[0] == '-') 482 { 483 // We have some options and these options MUST end with --. 484 const char *end_options = nullptr; 485 const char *s = command; 486 while (s && s[0]) 487 { 488 end_options = ::strstr (s, "--"); 489 if (end_options) 490 { 491 end_options += 2; // Get past the "--" 492 if (::isspace (end_options[0])) 493 { 494 expr = end_options; 495 while (::isspace (*expr)) 496 ++expr; 497 break; 498 } 499 } 500 s = end_options; 501 } 502 503 if (end_options) 504 { 505 Args args (llvm::StringRef(command, end_options - command)); 506 if (!ParseOptions (args, result)) 507 return false; 508 509 Error error (m_option_group.NotifyOptionParsingFinished()); 510 if (error.Fail()) 511 { 512 result.AppendError (error.AsCString()); 513 result.SetStatus (eReturnStatusFailed); 514 return false; 515 } 516 517 if (m_repl_option.GetOptionValue().GetCurrentValue()) 518 { 519 Target *target = m_interpreter.GetExecutionContext().GetTargetPtr(); 520 if (target) 521 { 522 // Drop into REPL 523 m_expr_lines.clear(); 524 m_expr_line_count = 0; 525 526 Debugger &debugger = target->GetDebugger(); 527 528 // Check if the LLDB command interpreter is sitting on top of a REPL that 529 // launched it... 530 if (debugger.CheckTopIOHandlerTypes(IOHandler::Type::CommandInterpreter, IOHandler::Type::REPL)) 531 { 532 // the LLDB command interpreter is sitting on top of a REPL that launched it, 533 // so just say the command interpreter is done and fall back to the existing REPL 534 m_interpreter.GetIOHandler(false)->SetIsDone(true); 535 } 536 else 537 { 538 // We are launching the REPL on top of the current LLDB command interpreter, 539 // so just push one 540 bool initialize = false; 541 Error repl_error; 542 REPLSP repl_sp (target->GetREPL(repl_error, m_command_options.language, nullptr, false)); 543 544 if (!repl_sp) 545 { 546 initialize = true; 547 repl_sp = target->GetREPL(repl_error, m_command_options.language, nullptr, true); 548 if (!repl_error.Success()) 549 { 550 result.SetError(repl_error); 551 return result.Succeeded(); 552 } 553 } 554 555 if (repl_sp) 556 { 557 if (initialize) 558 { 559 repl_sp->SetCommandOptions(m_command_options); 560 repl_sp->SetFormatOptions(m_format_options); 561 repl_sp->SetValueObjectDisplayOptions(m_varobj_options); 562 } 563 564 IOHandlerSP io_handler_sp (repl_sp->GetIOHandler()); 565 566 io_handler_sp->SetIsDone(false); 567 568 debugger.PushIOHandler(io_handler_sp); 569 } 570 else 571 { 572 repl_error.SetErrorStringWithFormat("Couldn't create a REPL for %s", Language::GetNameForLanguageType(m_command_options.language)); 573 result.SetError(repl_error); 574 return result.Succeeded(); 575 } 576 } 577 } 578 } 579 // No expression following options 580 else if (expr == nullptr || expr[0] == '\0') 581 { 582 GetMultilineExpression (); 583 return result.Succeeded(); 584 } 585 } 586 } 587 588 if (expr == nullptr) 589 expr = command; 590 591 if (EvaluateExpression (expr, &(result.GetOutputStream()), &(result.GetErrorStream()), &result)) 592 return true; 593 594 result.SetStatus (eReturnStatusFailed); 595 return false; 596 } 597