1 //===-- StopInfo.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 #include "lldb/Target/StopInfo.h" 11 12 // C Includes 13 // C++ Includes 14 #include <string> 15 16 // Other libraries and framework includes 17 // Project includes 18 #include "lldb/Core/Log.h" 19 #include "lldb/Breakpoint/Breakpoint.h" 20 #include "lldb/Breakpoint/BreakpointLocation.h" 21 #include "lldb/Breakpoint/StoppointCallbackContext.h" 22 #include "lldb/Breakpoint/Watchpoint.h" 23 #include "lldb/Core/Debugger.h" 24 #include "lldb/Core/StreamString.h" 25 #include "lldb/Core/ValueObject.h" 26 #include "lldb/Expression/UserExpression.h" 27 #include "lldb/Target/Target.h" 28 #include "lldb/Target/Thread.h" 29 #include "lldb/Target/ThreadPlan.h" 30 #include "lldb/Target/Process.h" 31 #include "lldb/Target/UnixSignals.h" 32 33 using namespace lldb; 34 using namespace lldb_private; 35 36 StopInfo::StopInfo (Thread &thread, uint64_t value) : 37 m_thread_wp (thread.shared_from_this()), 38 m_stop_id (thread.GetProcess()->GetStopID()), 39 m_resume_id (thread.GetProcess()->GetResumeID()), 40 m_value (value), 41 m_description (), 42 m_override_should_notify (eLazyBoolCalculate), 43 m_override_should_stop (eLazyBoolCalculate), 44 m_extended_info() 45 { 46 } 47 48 bool 49 StopInfo::IsValid () const 50 { 51 ThreadSP thread_sp (m_thread_wp.lock()); 52 if (thread_sp) 53 return thread_sp->GetProcess()->GetStopID() == m_stop_id; 54 return false; 55 } 56 57 void 58 StopInfo::MakeStopInfoValid () 59 { 60 ThreadSP thread_sp (m_thread_wp.lock()); 61 if (thread_sp) 62 { 63 m_stop_id = thread_sp->GetProcess()->GetStopID(); 64 m_resume_id = thread_sp->GetProcess()->GetResumeID(); 65 } 66 } 67 68 bool 69 StopInfo::HasTargetRunSinceMe () 70 { 71 ThreadSP thread_sp (m_thread_wp.lock()); 72 73 if (thread_sp) 74 { 75 lldb::StateType ret_type = thread_sp->GetProcess()->GetPrivateState(); 76 if (ret_type == eStateRunning) 77 { 78 return true; 79 } 80 else if (ret_type == eStateStopped) 81 { 82 // This is a little tricky. We want to count "run and stopped again before you could 83 // ask this question as a "TRUE" answer to HasTargetRunSinceMe. But we don't want to 84 // include any running of the target done for expressions. So we track both resumes, 85 // and resumes caused by expressions, and check if there are any resumes NOT caused 86 // by expressions. 87 88 uint32_t curr_resume_id = thread_sp->GetProcess()->GetResumeID(); 89 uint32_t last_user_expression_id = thread_sp->GetProcess()->GetLastUserExpressionResumeID (); 90 if (curr_resume_id == m_resume_id) 91 { 92 return false; 93 } 94 else if (curr_resume_id > last_user_expression_id) 95 { 96 return true; 97 } 98 } 99 } 100 return false; 101 } 102 103 //---------------------------------------------------------------------- 104 // StopInfoBreakpoint 105 //---------------------------------------------------------------------- 106 107 namespace lldb_private 108 { 109 class StopInfoBreakpoint : public StopInfo 110 { 111 public: 112 StopInfoBreakpoint (Thread &thread, break_id_t break_id) : 113 StopInfo (thread, break_id), 114 m_should_stop (false), 115 m_should_stop_is_valid (false), 116 m_should_perform_action (true), 117 m_address (LLDB_INVALID_ADDRESS), 118 m_break_id(LLDB_INVALID_BREAK_ID), 119 m_was_one_shot (false) 120 { 121 StoreBPInfo(); 122 } 123 124 StopInfoBreakpoint (Thread &thread, break_id_t break_id, bool should_stop) : 125 StopInfo (thread, break_id), 126 m_should_stop (should_stop), 127 m_should_stop_is_valid (true), 128 m_should_perform_action (true), 129 m_address (LLDB_INVALID_ADDRESS), 130 m_break_id(LLDB_INVALID_BREAK_ID), 131 m_was_one_shot (false) 132 { 133 StoreBPInfo(); 134 } 135 136 void 137 StoreBPInfo () 138 { 139 ThreadSP thread_sp (m_thread_wp.lock()); 140 if (thread_sp) 141 { 142 BreakpointSiteSP bp_site_sp (thread_sp->GetProcess()->GetBreakpointSiteList().FindByID (m_value)); 143 if (bp_site_sp) 144 { 145 if (bp_site_sp->GetNumberOfOwners() == 1) 146 { 147 BreakpointLocationSP bp_loc_sp = bp_site_sp->GetOwnerAtIndex(0); 148 if (bp_loc_sp) 149 { 150 m_break_id = bp_loc_sp->GetBreakpoint().GetID(); 151 m_was_one_shot = bp_loc_sp->GetBreakpoint().IsOneShot(); 152 } 153 } 154 m_address = bp_site_sp->GetLoadAddress(); 155 } 156 } 157 } 158 159 virtual ~StopInfoBreakpoint () 160 { 161 } 162 163 virtual bool 164 IsValidForOperatingSystemThread (Thread &thread) 165 { 166 ProcessSP process_sp (thread.GetProcess()); 167 if (process_sp) 168 { 169 BreakpointSiteSP bp_site_sp (process_sp->GetBreakpointSiteList().FindByID (m_value)); 170 if (bp_site_sp) 171 return bp_site_sp->ValidForThisThread (&thread); 172 } 173 return false; 174 } 175 176 virtual StopReason 177 GetStopReason () const 178 { 179 return eStopReasonBreakpoint; 180 } 181 182 virtual bool 183 ShouldStopSynchronous (Event *event_ptr) 184 { 185 ThreadSP thread_sp (m_thread_wp.lock()); 186 if (thread_sp) 187 { 188 if (!m_should_stop_is_valid) 189 { 190 // Only check once if we should stop at a breakpoint 191 BreakpointSiteSP bp_site_sp (thread_sp->GetProcess()->GetBreakpointSiteList().FindByID (m_value)); 192 if (bp_site_sp) 193 { 194 ExecutionContext exe_ctx (thread_sp->GetStackFrameAtIndex(0)); 195 StoppointCallbackContext context (event_ptr, exe_ctx, true); 196 bp_site_sp->BumpHitCounts(); 197 m_should_stop = bp_site_sp->ShouldStop (&context); 198 } 199 else 200 { 201 Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS)); 202 203 if (log) 204 log->Printf ("Process::%s could not find breakpoint site id: %" PRId64 "...", __FUNCTION__, m_value); 205 206 m_should_stop = true; 207 } 208 m_should_stop_is_valid = true; 209 } 210 return m_should_stop; 211 } 212 return false; 213 } 214 215 virtual bool 216 DoShouldNotify (Event *event_ptr) 217 { 218 ThreadSP thread_sp (m_thread_wp.lock()); 219 if (thread_sp) 220 { 221 BreakpointSiteSP bp_site_sp (thread_sp->GetProcess()->GetBreakpointSiteList().FindByID (m_value)); 222 if (bp_site_sp) 223 { 224 bool all_internal = true; 225 226 for (uint32_t i = 0; i < bp_site_sp->GetNumberOfOwners(); i++) 227 { 228 if (!bp_site_sp->GetOwnerAtIndex(i)->GetBreakpoint().IsInternal()) 229 { 230 all_internal = false; 231 break; 232 } 233 } 234 return all_internal == false; 235 } 236 } 237 return true; 238 } 239 240 virtual const char * 241 GetDescription () 242 { 243 if (m_description.empty()) 244 { 245 ThreadSP thread_sp (m_thread_wp.lock()); 246 if (thread_sp) 247 { 248 BreakpointSiteSP bp_site_sp (thread_sp->GetProcess()->GetBreakpointSiteList().FindByID (m_value)); 249 if (bp_site_sp) 250 { 251 StreamString strm; 252 // If we have just hit an internal breakpoint, and it has a kind description, print that instead of the 253 // full breakpoint printing: 254 if (bp_site_sp->IsInternal()) 255 { 256 size_t num_owners = bp_site_sp->GetNumberOfOwners(); 257 for (size_t idx = 0; idx < num_owners; idx++) 258 { 259 const char *kind = bp_site_sp->GetOwnerAtIndex(idx)->GetBreakpoint().GetBreakpointKind(); 260 if (kind != NULL) 261 { 262 m_description.assign (kind); 263 return kind; 264 } 265 } 266 } 267 268 strm.Printf("breakpoint "); 269 bp_site_sp->GetDescription(&strm, eDescriptionLevelBrief); 270 m_description.swap (strm.GetString()); 271 } 272 else 273 { 274 StreamString strm; 275 if (m_break_id != LLDB_INVALID_BREAK_ID) 276 { 277 BreakpointSP break_sp = thread_sp->GetProcess()->GetTarget().GetBreakpointByID(m_break_id); 278 if (break_sp) 279 { 280 if (break_sp->IsInternal()) 281 { 282 const char *kind = break_sp->GetBreakpointKind(); 283 if (kind) 284 strm.Printf ("internal %s breakpoint(%d).", kind, m_break_id); 285 else 286 strm.Printf ("internal breakpoint(%d).", m_break_id); 287 } 288 else 289 { 290 strm.Printf ("breakpoint %d.", m_break_id); 291 } 292 } 293 else 294 { 295 if (m_was_one_shot) 296 strm.Printf ("one-shot breakpoint %d", m_break_id); 297 else 298 strm.Printf ("breakpoint %d which has been deleted.", m_break_id); 299 } 300 } 301 else if (m_address == LLDB_INVALID_ADDRESS) 302 strm.Printf("breakpoint site %" PRIi64 " which has been deleted - unknown address", m_value); 303 else 304 strm.Printf("breakpoint site %" PRIi64 " which has been deleted - was at 0x%" PRIx64, m_value, m_address); 305 306 m_description.swap (strm.GetString()); 307 } 308 } 309 } 310 return m_description.c_str(); 311 } 312 313 protected: 314 bool 315 ShouldStop (Event *event_ptr) 316 { 317 // This just reports the work done by PerformAction or the synchronous stop. It should 318 // only ever get called after they have had a chance to run. 319 assert (m_should_stop_is_valid); 320 return m_should_stop; 321 } 322 323 virtual void 324 PerformAction (Event *event_ptr) 325 { 326 if (!m_should_perform_action) 327 return; 328 m_should_perform_action = false; 329 330 ThreadSP thread_sp (m_thread_wp.lock()); 331 332 if (thread_sp) 333 { 334 Log *log = lldb_private::GetLogIfAnyCategoriesSet (LIBLLDB_LOG_BREAKPOINTS | LIBLLDB_LOG_STEP); 335 336 if (!thread_sp->IsValid()) 337 { 338 // This shouldn't ever happen, but just in case, don't do more harm. 339 if (log) 340 { 341 log->Printf ("PerformAction got called with an invalid thread."); 342 } 343 m_should_stop = true; 344 m_should_stop_is_valid = true; 345 return; 346 } 347 348 BreakpointSiteSP bp_site_sp (thread_sp->GetProcess()->GetBreakpointSiteList().FindByID (m_value)); 349 std::unordered_set<break_id_t> precondition_breakpoints; 350 351 if (bp_site_sp) 352 { 353 // Let's copy the owners list out of the site and store them in a local list. That way if 354 // one of the breakpoint actions changes the site, then we won't be operating on a bad list. 355 BreakpointLocationCollection site_locations; 356 size_t num_owners = bp_site_sp->CopyOwnersList(site_locations); 357 358 if (num_owners == 0) 359 { 360 m_should_stop = true; 361 } 362 else 363 { 364 // We go through each location, and test first its precondition - this overrides everything. Note, 365 // we only do this once per breakpoint - not once per location... 366 // Then check the condition. If the condition says to stop, 367 // then we run the callback for that location. If that callback says to stop as well, then 368 // we set m_should_stop to true; we are going to stop. 369 // But we still want to give all the breakpoints whose conditions say we are going to stop a 370 // chance to run their callbacks. 371 // Of course if any callback restarts the target by putting "continue" in the callback, then 372 // we're going to restart, without running the rest of the callbacks. And in this case we will 373 // end up not stopping even if another location said we should stop. But that's better than not 374 // running all the callbacks. 375 376 m_should_stop = false; 377 378 ExecutionContext exe_ctx (thread_sp->GetStackFrameAtIndex(0)); 379 Process *process = exe_ctx.GetProcessPtr(); 380 if (process->GetModIDRef().IsLastResumeForUserExpression()) 381 { 382 // If we are in the middle of evaluating an expression, don't run asynchronous breakpoint commands or 383 // expressions. That could lead to infinite recursion if the command or condition re-calls the function 384 // with this breakpoint. 385 // TODO: We can keep a list of the breakpoints we've seen while running expressions in the nested 386 // PerformAction calls that can arise when the action runs a function that hits another breakpoint, 387 // and only stop running commands when we see the same breakpoint hit a second time. 388 389 m_should_stop_is_valid = true; 390 if (log) 391 log->Printf ("StopInfoBreakpoint::PerformAction - Hit a breakpoint while running an expression," 392 " not running commands to avoid recursion."); 393 bool ignoring_breakpoints = process->GetIgnoreBreakpointsInExpressions(); 394 if (ignoring_breakpoints) 395 { 396 m_should_stop = false; 397 // Internal breakpoints will always stop. 398 for (size_t j = 0; j < num_owners; j++) 399 { 400 lldb::BreakpointLocationSP bp_loc_sp = bp_site_sp->GetOwnerAtIndex(j); 401 if (bp_loc_sp->GetBreakpoint().IsInternal()) 402 { 403 m_should_stop = true; 404 break; 405 } 406 } 407 } 408 else 409 { 410 m_should_stop = true; 411 } 412 if (log) 413 log->Printf ("StopInfoBreakpoint::PerformAction - in expression, continuing: %s.", 414 m_should_stop ? "true" : "false"); 415 process->GetTarget().GetDebugger().GetAsyncOutputStream()->Printf("Warning: hit breakpoint while " 416 "running function, skipping commands and conditions to prevent recursion."); 417 return; 418 } 419 420 StoppointCallbackContext context (event_ptr, exe_ctx, false); 421 422 // For safety's sake let's also grab an extra reference to the breakpoint owners of the locations we're 423 // going to examine, since the locations are going to have to get back to their breakpoints, and the 424 // locations don't keep their owners alive. I'm just sticking the BreakpointSP's in a vector since 425 // I'm only using it to locally increment their retain counts. 426 427 std::vector<lldb::BreakpointSP> location_owners; 428 429 for (size_t j = 0; j < num_owners; j++) 430 { 431 BreakpointLocationSP loc(site_locations.GetByIndex(j)); 432 location_owners.push_back(loc->GetBreakpoint().shared_from_this()); 433 434 } 435 436 for (size_t j = 0; j < num_owners; j++) 437 { 438 lldb::BreakpointLocationSP bp_loc_sp = site_locations.GetByIndex(j); 439 440 // If another action disabled this breakpoint or its location, then don't run the actions. 441 if (!bp_loc_sp->IsEnabled() || !bp_loc_sp->GetBreakpoint().IsEnabled()) 442 continue; 443 444 // The breakpoint site may have many locations associated with it, not all of them valid for 445 // this thread. Skip the ones that aren't: 446 if (!bp_loc_sp->ValidForThisThread(thread_sp.get())) 447 { 448 if (log) 449 { 450 StreamString s; 451 bp_loc_sp->GetDescription(&s, eDescriptionLevelBrief); 452 log->Printf ("Breakpoint %s hit on thread 0x%llx but it was not for this thread, continuing.", 453 s.GetData(), 454 static_cast<unsigned long long>(thread_sp->GetID())); 455 } 456 continue; 457 } 458 459 // First run the precondition, but since the precondition is per breakpoint, only run it once 460 // per breakpoint. 461 std::pair<std::unordered_set<break_id_t>::iterator, bool> result 462 = precondition_breakpoints.insert(bp_loc_sp->GetBreakpoint().GetID()); 463 if (!result.second) 464 continue; 465 466 bool precondition_result = bp_loc_sp->GetBreakpoint().EvaluatePrecondition(context); 467 if (!precondition_result) 468 continue; 469 470 // Next run the condition for the breakpoint. If that says we should stop, then we'll run 471 // the callback for the breakpoint. If the callback says we shouldn't stop that will win. 472 473 if (bp_loc_sp->GetConditionText() != NULL) 474 { 475 Error condition_error; 476 bool condition_says_stop = bp_loc_sp->ConditionSaysStop(exe_ctx, condition_error); 477 478 if (!condition_error.Success()) 479 { 480 Debugger &debugger = exe_ctx.GetTargetRef().GetDebugger(); 481 StreamSP error_sp = debugger.GetAsyncErrorStream (); 482 error_sp->Printf ("Stopped due to an error evaluating condition of breakpoint "); 483 bp_loc_sp->GetDescription (error_sp.get(), eDescriptionLevelBrief); 484 error_sp->Printf (": \"%s\"", 485 bp_loc_sp->GetConditionText()); 486 error_sp->EOL(); 487 const char *err_str = condition_error.AsCString("<Unknown Error>"); 488 if (log) 489 log->Printf("Error evaluating condition: \"%s\"\n", err_str); 490 491 error_sp->PutCString (err_str); 492 error_sp->EOL(); 493 error_sp->Flush(); 494 } 495 else 496 { 497 if (log) 498 { 499 StreamString s; 500 bp_loc_sp->GetDescription(&s, eDescriptionLevelBrief); 501 log->Printf ("Condition evaluated for breakpoint %s on thread 0x%llx conditon_says_stop: %i.", 502 s.GetData(), 503 static_cast<unsigned long long>(thread_sp->GetID()), 504 condition_says_stop); 505 } 506 if (!condition_says_stop) 507 { 508 // We don't want to increment the hit count of breakpoints if the condition fails. 509 // We've already bumped it by the time we get here, so undo the bump: 510 bp_loc_sp->UndoBumpHitCount(); 511 continue; 512 } 513 } 514 } 515 516 bool callback_says_stop; 517 518 // FIXME: For now the callbacks have to run in async mode - the first time we restart we need 519 // to get out of there. So set it here. 520 // When we figure out how to nest breakpoint hits then this will change. 521 522 Debugger &debugger = thread_sp->CalculateTarget()->GetDebugger(); 523 bool old_async = debugger.GetAsyncExecution(); 524 debugger.SetAsyncExecution (true); 525 526 callback_says_stop = bp_loc_sp->InvokeCallback (&context); 527 528 debugger.SetAsyncExecution (old_async); 529 530 if (callback_says_stop) 531 m_should_stop = true; 532 533 // If we are going to stop for this breakpoint, then remove the breakpoint. 534 if (callback_says_stop && bp_loc_sp && bp_loc_sp->GetBreakpoint().IsOneShot()) 535 { 536 thread_sp->GetProcess()->GetTarget().RemoveBreakpointByID (bp_loc_sp->GetBreakpoint().GetID()); 537 } 538 539 // Also make sure that the callback hasn't continued the target. 540 // If it did, when we'll set m_should_start to false and get out of here. 541 if (HasTargetRunSinceMe ()) 542 { 543 m_should_stop = false; 544 break; 545 } 546 } 547 } 548 // We've figured out what this stop wants to do, so mark it as valid so we don't compute it again. 549 m_should_stop_is_valid = true; 550 551 } 552 else 553 { 554 m_should_stop = true; 555 m_should_stop_is_valid = true; 556 Log * log_process(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS)); 557 558 if (log_process) 559 log_process->Printf ("Process::%s could not find breakpoint site id: %" PRId64 "...", __FUNCTION__, m_value); 560 } 561 if (log) 562 log->Printf ("Process::%s returning from action with m_should_stop: %d.", __FUNCTION__, m_should_stop); 563 } 564 } 565 566 private: 567 bool m_should_stop; 568 bool m_should_stop_is_valid; 569 bool m_should_perform_action; // Since we are trying to preserve the "state" of the system even if we run functions 570 // etc. behind the users backs, we need to make sure we only REALLY perform the action once. 571 lldb::addr_t m_address; // We use this to capture the breakpoint site address when we create the StopInfo, 572 // in case somebody deletes it between the time the StopInfo is made and the 573 // description is asked for. 574 lldb::break_id_t m_break_id; 575 bool m_was_one_shot; 576 }; 577 578 579 //---------------------------------------------------------------------- 580 // StopInfoWatchpoint 581 //---------------------------------------------------------------------- 582 583 class StopInfoWatchpoint : public StopInfo 584 { 585 public: 586 // Make sure watchpoint is properly disabled and subsequently enabled while performing watchpoint actions. 587 class WatchpointSentry { 588 public: 589 WatchpointSentry(Process *p, Watchpoint *w): 590 process(p), 591 watchpoint(w) 592 { 593 if (process && watchpoint) 594 { 595 const bool notify = false; 596 watchpoint->TurnOnEphemeralMode(); 597 process->DisableWatchpoint(watchpoint, notify); 598 } 599 } 600 ~WatchpointSentry() 601 { 602 if (process && watchpoint) 603 { 604 if (!watchpoint->IsDisabledDuringEphemeralMode()) 605 { 606 const bool notify = false; 607 process->EnableWatchpoint(watchpoint, notify); 608 } 609 watchpoint->TurnOffEphemeralMode(); 610 } 611 } 612 private: 613 Process *process; 614 Watchpoint *watchpoint; 615 }; 616 617 StopInfoWatchpoint (Thread &thread, break_id_t watch_id, lldb::addr_t watch_hit_addr) : 618 StopInfo(thread, watch_id), 619 m_should_stop(false), 620 m_should_stop_is_valid(false), 621 m_watch_hit_addr(watch_hit_addr) 622 { 623 } 624 625 virtual ~StopInfoWatchpoint () 626 { 627 } 628 629 virtual StopReason 630 GetStopReason () const 631 { 632 return eStopReasonWatchpoint; 633 } 634 635 virtual const char * 636 GetDescription () 637 { 638 if (m_description.empty()) 639 { 640 StreamString strm; 641 strm.Printf("watchpoint %" PRIi64, m_value); 642 m_description.swap (strm.GetString()); 643 } 644 return m_description.c_str(); 645 } 646 647 protected: 648 virtual bool 649 ShouldStopSynchronous (Event *event_ptr) 650 { 651 // ShouldStop() method is idempotent and should not affect hit count. 652 // See Process::RunPrivateStateThread()->Process()->HandlePrivateEvent() 653 // -->Process()::ShouldBroadcastEvent()->ThreadList::ShouldStop()-> 654 // Thread::ShouldStop()->ThreadPlanBase::ShouldStop()-> 655 // StopInfoWatchpoint::ShouldStop() and 656 // Event::DoOnRemoval()->Process::ProcessEventData::DoOnRemoval()-> 657 // StopInfoWatchpoint::PerformAction(). 658 if (m_should_stop_is_valid) 659 return m_should_stop; 660 661 ThreadSP thread_sp (m_thread_wp.lock()); 662 if (thread_sp) 663 { 664 WatchpointSP wp_sp (thread_sp->CalculateTarget()->GetWatchpointList().FindByID(GetValue())); 665 if (wp_sp) 666 { 667 // Check if we should stop at a watchpoint. 668 ExecutionContext exe_ctx (thread_sp->GetStackFrameAtIndex(0)); 669 StoppointCallbackContext context (event_ptr, exe_ctx, true); 670 m_should_stop = wp_sp->ShouldStop (&context); 671 } 672 else 673 { 674 Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS)); 675 676 if (log) 677 log->Printf ("Process::%s could not find watchpoint location id: %" PRId64 "...", 678 __FUNCTION__, GetValue()); 679 680 m_should_stop = true; 681 } 682 } 683 m_should_stop_is_valid = true; 684 return m_should_stop; 685 } 686 687 bool 688 ShouldStop (Event *event_ptr) 689 { 690 // This just reports the work done by PerformAction or the synchronous stop. It should 691 // only ever get called after they have had a chance to run. 692 assert (m_should_stop_is_valid); 693 return m_should_stop; 694 } 695 696 virtual void 697 PerformAction (Event *event_ptr) 698 { 699 Log *log = lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_WATCHPOINTS); 700 // We're going to calculate if we should stop or not in some way during the course of 701 // this code. Also by default we're going to stop, so set that here. 702 m_should_stop = true; 703 704 ThreadSP thread_sp (m_thread_wp.lock()); 705 if (thread_sp) 706 { 707 708 WatchpointSP wp_sp (thread_sp->CalculateTarget()->GetWatchpointList().FindByID(GetValue())); 709 if (wp_sp) 710 { 711 ExecutionContext exe_ctx (thread_sp->GetStackFrameAtIndex(0)); 712 Process* process = exe_ctx.GetProcessPtr(); 713 714 // This sentry object makes sure the current watchpoint is disabled while performing watchpoint actions, 715 // and it is then enabled after we are finished. 716 WatchpointSentry sentry(process, wp_sp.get()); 717 718 { 719 // check if this process is running on an architecture where watchpoints trigger 720 // before the associated instruction runs. if so, disable the WP, single-step and then 721 // re-enable the watchpoint 722 if (process) 723 { 724 uint32_t num; 725 bool wp_triggers_after; 726 if (process->GetWatchpointSupportInfo(num, wp_triggers_after).Success()) 727 { 728 if (!wp_triggers_after) 729 { 730 StopInfoSP stored_stop_info_sp = thread_sp->GetStopInfo(); 731 assert (stored_stop_info_sp.get() == this); 732 733 ThreadPlanSP new_plan_sp(thread_sp->QueueThreadPlanForStepSingleInstruction(false, // step-over 734 false, // abort_other_plans 735 true)); // stop_other_threads 736 new_plan_sp->SetIsMasterPlan (true); 737 new_plan_sp->SetOkayToDiscard (false); 738 new_plan_sp->SetPrivate (true); 739 process->GetThreadList().SetSelectedThreadByID (thread_sp->GetID()); 740 process->ResumeSynchronous(NULL); 741 process->GetThreadList().SetSelectedThreadByID (thread_sp->GetID()); 742 thread_sp->SetStopInfo(stored_stop_info_sp); 743 } 744 } 745 } 746 } 747 748 /* 749 * MIPS: Last 3bits of the watchpoint address are masked by the kernel. For example: 750 * 'n' is at 0x120010d00 and 'm' is 0x120010d04. When a watchpoint is set at 'm', then 751 * watch exception is generated even when 'n' is read/written. To handle this case, 752 * server emulates the instruction at PC and finds the base address of the load/store 753 * instruction and appends it in the description of the stop-info packet. If watchpoint 754 * is not set on this address by user then this do not stop. 755 */ 756 if (m_watch_hit_addr != LLDB_INVALID_ADDRESS) 757 { 758 WatchpointSP wp_hit_sp = thread_sp->CalculateTarget()->GetWatchpointList().FindByAddress(m_watch_hit_addr); 759 if (!wp_hit_sp) 760 m_should_stop = false; 761 } 762 763 if (m_should_stop && wp_sp->GetConditionText() != NULL) 764 { 765 // We need to make sure the user sees any parse errors in their condition, so we'll hook the 766 // constructor errors up to the debugger's Async I/O. 767 ExpressionResults result_code; 768 EvaluateExpressionOptions expr_options; 769 expr_options.SetUnwindOnError(true); 770 expr_options.SetIgnoreBreakpoints(true); 771 ValueObjectSP result_value_sp; 772 Error error; 773 result_code = UserExpression::Evaluate (exe_ctx, 774 expr_options, 775 wp_sp->GetConditionText(), 776 NULL, 777 result_value_sp, 778 error); 779 780 if (result_code == eExpressionCompleted) 781 { 782 if (result_value_sp) 783 { 784 Scalar scalar_value; 785 if (result_value_sp->ResolveValue (scalar_value)) 786 { 787 if (scalar_value.ULongLong(1) == 0) 788 { 789 // We have been vetoed. This takes precedence over querying 790 // the watchpoint whether it should stop (aka ignore count and 791 // friends). See also StopInfoWatchpoint::ShouldStop() as well 792 // as Process::ProcessEventData::DoOnRemoval(). 793 m_should_stop = false; 794 } 795 else 796 m_should_stop = true; 797 if (log) 798 log->Printf("Condition successfully evaluated, result is %s.\n", 799 m_should_stop ? "true" : "false"); 800 } 801 else 802 { 803 m_should_stop = true; 804 if (log) 805 log->Printf("Failed to get an integer result from the expression."); 806 } 807 } 808 } 809 else 810 { 811 Debugger &debugger = exe_ctx.GetTargetRef().GetDebugger(); 812 StreamSP error_sp = debugger.GetAsyncErrorStream (); 813 error_sp->Printf ("Stopped due to an error evaluating condition of watchpoint "); 814 wp_sp->GetDescription (error_sp.get(), eDescriptionLevelBrief); 815 error_sp->Printf (": \"%s\"", 816 wp_sp->GetConditionText()); 817 error_sp->EOL(); 818 const char *err_str = error.AsCString("<Unknown Error>"); 819 if (log) 820 log->Printf("Error evaluating condition: \"%s\"\n", err_str); 821 822 error_sp->PutCString (err_str); 823 error_sp->EOL(); 824 error_sp->Flush(); 825 // If the condition fails to be parsed or run, we should stop. 826 m_should_stop = true; 827 } 828 } 829 830 // If the condition says to stop, we run the callback to further decide whether to stop. 831 if (m_should_stop) 832 { 833 StoppointCallbackContext context (event_ptr, exe_ctx, false); 834 bool stop_requested = wp_sp->InvokeCallback (&context); 835 // Also make sure that the callback hasn't continued the target. 836 // If it did, when we'll set m_should_stop to false and get out of here. 837 if (HasTargetRunSinceMe ()) 838 m_should_stop = false; 839 840 if (m_should_stop && !stop_requested) 841 { 842 // We have been vetoed by the callback mechanism. 843 m_should_stop = false; 844 } 845 } 846 // Finally, if we are going to stop, print out the new & old values: 847 if (m_should_stop) 848 { 849 wp_sp->CaptureWatchedValue(exe_ctx); 850 851 Debugger &debugger = exe_ctx.GetTargetRef().GetDebugger(); 852 StreamSP output_sp = debugger.GetAsyncOutputStream (); 853 wp_sp->DumpSnapshots(output_sp.get()); 854 output_sp->EOL(); 855 output_sp->Flush(); 856 } 857 858 } 859 else 860 { 861 Log * log_process(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS)); 862 863 if (log_process) 864 log_process->Printf ("Process::%s could not find watchpoint id: %" PRId64 "...", __FUNCTION__, m_value); 865 } 866 if (log) 867 log->Printf ("Process::%s returning from action with m_should_stop: %d.", __FUNCTION__, m_should_stop); 868 869 m_should_stop_is_valid = true; 870 } 871 } 872 873 private: 874 bool m_should_stop; 875 bool m_should_stop_is_valid; 876 lldb::addr_t m_watch_hit_addr; 877 }; 878 879 880 881 //---------------------------------------------------------------------- 882 // StopInfoUnixSignal 883 //---------------------------------------------------------------------- 884 885 class StopInfoUnixSignal : public StopInfo 886 { 887 public: 888 889 StopInfoUnixSignal (Thread &thread, int signo, const char *description) : 890 StopInfo (thread, signo) 891 { 892 SetDescription (description); 893 } 894 895 virtual ~StopInfoUnixSignal () 896 { 897 } 898 899 900 virtual StopReason 901 GetStopReason () const 902 { 903 return eStopReasonSignal; 904 } 905 906 virtual bool 907 ShouldStopSynchronous (Event *event_ptr) 908 { 909 ThreadSP thread_sp (m_thread_wp.lock()); 910 if (thread_sp) 911 return thread_sp->GetProcess()->GetUnixSignals()->GetShouldStop(m_value); 912 return false; 913 } 914 915 virtual bool 916 ShouldStop (Event *event_ptr) 917 { 918 ThreadSP thread_sp (m_thread_wp.lock()); 919 if (thread_sp) 920 return thread_sp->GetProcess()->GetUnixSignals()->GetShouldStop(m_value); 921 return false; 922 } 923 924 925 // If should stop returns false, check if we should notify of this event 926 virtual bool 927 DoShouldNotify (Event *event_ptr) 928 { 929 ThreadSP thread_sp (m_thread_wp.lock()); 930 if (thread_sp) 931 { 932 bool should_notify = thread_sp->GetProcess()->GetUnixSignals()->GetShouldNotify(m_value); 933 if (should_notify) 934 { 935 StreamString strm; 936 strm.Printf ("thread %d received signal: %s", 937 thread_sp->GetIndexID(), 938 thread_sp->GetProcess()->GetUnixSignals()->GetSignalAsCString(m_value)); 939 Process::ProcessEventData::AddRestartedReason(event_ptr, strm.GetData()); 940 } 941 return should_notify; 942 } 943 return true; 944 } 945 946 947 virtual void 948 WillResume (lldb::StateType resume_state) 949 { 950 ThreadSP thread_sp (m_thread_wp.lock()); 951 if (thread_sp) 952 { 953 if (thread_sp->GetProcess()->GetUnixSignals()->GetShouldSuppress(m_value) == false) 954 thread_sp->SetResumeSignal(m_value); 955 } 956 } 957 958 virtual const char * 959 GetDescription () 960 { 961 if (m_description.empty()) 962 { 963 ThreadSP thread_sp (m_thread_wp.lock()); 964 if (thread_sp) 965 { 966 StreamString strm; 967 const char *signal_name = thread_sp->GetProcess()->GetUnixSignals()->GetSignalAsCString(m_value); 968 if (signal_name) 969 strm.Printf("signal %s", signal_name); 970 else 971 strm.Printf("signal %" PRIi64, m_value); 972 m_description.swap (strm.GetString()); 973 } 974 } 975 return m_description.c_str(); 976 } 977 }; 978 979 //---------------------------------------------------------------------- 980 // StopInfoTrace 981 //---------------------------------------------------------------------- 982 983 class StopInfoTrace : public StopInfo 984 { 985 public: 986 987 StopInfoTrace (Thread &thread) : 988 StopInfo (thread, LLDB_INVALID_UID) 989 { 990 } 991 992 virtual ~StopInfoTrace () 993 { 994 } 995 996 virtual StopReason 997 GetStopReason () const 998 { 999 return eStopReasonTrace; 1000 } 1001 1002 virtual const char * 1003 GetDescription () 1004 { 1005 if (m_description.empty()) 1006 return "trace"; 1007 else 1008 return m_description.c_str(); 1009 } 1010 }; 1011 1012 1013 //---------------------------------------------------------------------- 1014 // StopInfoException 1015 //---------------------------------------------------------------------- 1016 1017 class StopInfoException : public StopInfo 1018 { 1019 public: 1020 1021 StopInfoException (Thread &thread, const char *description) : 1022 StopInfo (thread, LLDB_INVALID_UID) 1023 { 1024 if (description) 1025 SetDescription (description); 1026 } 1027 1028 virtual 1029 ~StopInfoException () 1030 { 1031 } 1032 1033 virtual StopReason 1034 GetStopReason () const 1035 { 1036 return eStopReasonException; 1037 } 1038 1039 virtual const char * 1040 GetDescription () 1041 { 1042 if (m_description.empty()) 1043 return "exception"; 1044 else 1045 return m_description.c_str(); 1046 } 1047 }; 1048 1049 1050 //---------------------------------------------------------------------- 1051 // StopInfoThreadPlan 1052 //---------------------------------------------------------------------- 1053 1054 class StopInfoThreadPlan : public StopInfo 1055 { 1056 public: 1057 1058 StopInfoThreadPlan (ThreadPlanSP &plan_sp, ValueObjectSP &return_valobj_sp, ExpressionVariableSP &expression_variable_sp) : 1059 StopInfo (plan_sp->GetThread(), LLDB_INVALID_UID), 1060 m_plan_sp (plan_sp), 1061 m_return_valobj_sp (return_valobj_sp), 1062 m_expression_variable_sp (expression_variable_sp) 1063 { 1064 } 1065 1066 virtual ~StopInfoThreadPlan () 1067 { 1068 } 1069 1070 virtual StopReason 1071 GetStopReason () const 1072 { 1073 return eStopReasonPlanComplete; 1074 } 1075 1076 virtual const char * 1077 GetDescription () 1078 { 1079 if (m_description.empty()) 1080 { 1081 StreamString strm; 1082 m_plan_sp->GetDescription (&strm, eDescriptionLevelBrief); 1083 m_description.swap (strm.GetString()); 1084 } 1085 return m_description.c_str(); 1086 } 1087 1088 ValueObjectSP 1089 GetReturnValueObject() 1090 { 1091 return m_return_valobj_sp; 1092 } 1093 1094 ExpressionVariableSP 1095 GetExpressionVariable() 1096 { 1097 return m_expression_variable_sp; 1098 } 1099 1100 protected: 1101 virtual bool 1102 ShouldStop (Event *event_ptr) 1103 { 1104 if (m_plan_sp) 1105 return m_plan_sp->ShouldStop(event_ptr); 1106 else 1107 return StopInfo::ShouldStop(event_ptr); 1108 } 1109 1110 private: 1111 ThreadPlanSP m_plan_sp; 1112 ValueObjectSP m_return_valobj_sp; 1113 ExpressionVariableSP m_expression_variable_sp; 1114 }; 1115 1116 class StopInfoExec : public StopInfo 1117 { 1118 public: 1119 1120 StopInfoExec (Thread &thread) : 1121 StopInfo (thread, LLDB_INVALID_UID), 1122 m_performed_action (false) 1123 { 1124 } 1125 1126 virtual 1127 ~StopInfoExec () 1128 { 1129 } 1130 1131 virtual StopReason 1132 GetStopReason () const 1133 { 1134 return eStopReasonExec; 1135 } 1136 1137 virtual const char * 1138 GetDescription () 1139 { 1140 return "exec"; 1141 } 1142 protected: 1143 1144 virtual void 1145 PerformAction (Event *event_ptr) 1146 { 1147 // Only perform the action once 1148 if (m_performed_action) 1149 return; 1150 m_performed_action = true; 1151 ThreadSP thread_sp (m_thread_wp.lock()); 1152 if (thread_sp) 1153 thread_sp->GetProcess()->DidExec(); 1154 } 1155 1156 bool m_performed_action; 1157 }; 1158 1159 } // namespace lldb_private 1160 1161 StopInfoSP 1162 StopInfo::CreateStopReasonWithBreakpointSiteID (Thread &thread, break_id_t break_id) 1163 { 1164 return StopInfoSP (new StopInfoBreakpoint (thread, break_id)); 1165 } 1166 1167 StopInfoSP 1168 StopInfo::CreateStopReasonWithBreakpointSiteID (Thread &thread, break_id_t break_id, bool should_stop) 1169 { 1170 return StopInfoSP (new StopInfoBreakpoint (thread, break_id, should_stop)); 1171 } 1172 1173 StopInfoSP 1174 StopInfo::CreateStopReasonWithWatchpointID (Thread &thread, break_id_t watch_id, lldb::addr_t watch_hit_addr) 1175 { 1176 return StopInfoSP (new StopInfoWatchpoint (thread, watch_id, watch_hit_addr)); 1177 } 1178 1179 StopInfoSP 1180 StopInfo::CreateStopReasonWithSignal (Thread &thread, int signo, const char *description) 1181 { 1182 return StopInfoSP (new StopInfoUnixSignal (thread, signo, description)); 1183 } 1184 1185 StopInfoSP 1186 StopInfo::CreateStopReasonToTrace (Thread &thread) 1187 { 1188 return StopInfoSP (new StopInfoTrace (thread)); 1189 } 1190 1191 StopInfoSP 1192 StopInfo::CreateStopReasonWithPlan (ThreadPlanSP &plan_sp, 1193 ValueObjectSP return_valobj_sp, 1194 ExpressionVariableSP expression_variable_sp) 1195 { 1196 return StopInfoSP (new StopInfoThreadPlan (plan_sp, return_valobj_sp, expression_variable_sp)); 1197 } 1198 1199 StopInfoSP 1200 StopInfo::CreateStopReasonWithException (Thread &thread, const char *description) 1201 { 1202 return StopInfoSP (new StopInfoException (thread, description)); 1203 } 1204 1205 StopInfoSP 1206 StopInfo::CreateStopReasonWithExec (Thread &thread) 1207 { 1208 return StopInfoSP (new StopInfoExec (thread)); 1209 } 1210 1211 ValueObjectSP 1212 StopInfo::GetReturnValueObject(StopInfoSP &stop_info_sp) 1213 { 1214 if (stop_info_sp && stop_info_sp->GetStopReason() == eStopReasonPlanComplete) 1215 { 1216 StopInfoThreadPlan *plan_stop_info = static_cast<StopInfoThreadPlan *>(stop_info_sp.get()); 1217 return plan_stop_info->GetReturnValueObject(); 1218 } 1219 else 1220 return ValueObjectSP(); 1221 } 1222 1223 ExpressionVariableSP 1224 StopInfo::GetExpressionVariable(StopInfoSP &stop_info_sp) 1225 { 1226 if (stop_info_sp && stop_info_sp->GetStopReason() == eStopReasonPlanComplete) 1227 { 1228 StopInfoThreadPlan *plan_stop_info = static_cast<StopInfoThreadPlan *>(stop_info_sp.get()); 1229 return plan_stop_info->GetExpressionVariable(); 1230 } 1231 else 1232 return ExpressionVariableSP(); 1233 } 1234