1 //===-- Debugger.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 "lldb/Core/Debugger.h"
10 
11 #include "lldb/Breakpoint/Breakpoint.h"
12 #include "lldb/Core/DebuggerEvents.h"
13 #include "lldb/Core/FormatEntity.h"
14 #include "lldb/Core/Mangled.h"
15 #include "lldb/Core/ModuleList.h"
16 #include "lldb/Core/PluginManager.h"
17 #include "lldb/Core/StreamAsynchronousIO.h"
18 #include "lldb/Core/StreamFile.h"
19 #include "lldb/DataFormatters/DataVisualization.h"
20 #include "lldb/Expression/REPL.h"
21 #include "lldb/Host/File.h"
22 #include "lldb/Host/FileSystem.h"
23 #include "lldb/Host/HostInfo.h"
24 #include "lldb/Host/Terminal.h"
25 #include "lldb/Host/ThreadLauncher.h"
26 #include "lldb/Interpreter/CommandInterpreter.h"
27 #include "lldb/Interpreter/CommandReturnObject.h"
28 #include "lldb/Interpreter/OptionValue.h"
29 #include "lldb/Interpreter/OptionValueLanguage.h"
30 #include "lldb/Interpreter/OptionValueProperties.h"
31 #include "lldb/Interpreter/OptionValueSInt64.h"
32 #include "lldb/Interpreter/OptionValueString.h"
33 #include "lldb/Interpreter/Property.h"
34 #include "lldb/Interpreter/ScriptInterpreter.h"
35 #include "lldb/Symbol/Function.h"
36 #include "lldb/Symbol/Symbol.h"
37 #include "lldb/Symbol/SymbolContext.h"
38 #include "lldb/Target/Language.h"
39 #include "lldb/Target/Process.h"
40 #include "lldb/Target/StructuredDataPlugin.h"
41 #include "lldb/Target/Target.h"
42 #include "lldb/Target/TargetList.h"
43 #include "lldb/Target/Thread.h"
44 #include "lldb/Target/ThreadList.h"
45 #include "lldb/Utility/AnsiTerminal.h"
46 #include "lldb/Utility/Event.h"
47 #include "lldb/Utility/LLDBLog.h"
48 #include "lldb/Utility/Listener.h"
49 #include "lldb/Utility/Log.h"
50 #include "lldb/Utility/Reproducer.h"
51 #include "lldb/Utility/ReproducerProvider.h"
52 #include "lldb/Utility/State.h"
53 #include "lldb/Utility/Stream.h"
54 #include "lldb/Utility/StreamCallback.h"
55 #include "lldb/Utility/StreamString.h"
56 
57 #if defined(_WIN32)
58 #include "lldb/Host/windows/PosixApi.h"
59 #include "lldb/Host/windows/windows.h"
60 #endif
61 
62 #include "llvm/ADT/None.h"
63 #include "llvm/ADT/STLExtras.h"
64 #include "llvm/ADT/StringRef.h"
65 #include "llvm/ADT/iterator.h"
66 #include "llvm/Support/DynamicLibrary.h"
67 #include "llvm/Support/FileSystem.h"
68 #include "llvm/Support/Process.h"
69 #include "llvm/Support/Threading.h"
70 #include "llvm/Support/raw_ostream.h"
71 
72 #include <cstdio>
73 #include <cstdlib>
74 #include <cstring>
75 #include <list>
76 #include <memory>
77 #include <mutex>
78 #include <set>
79 #include <string>
80 #include <system_error>
81 
82 // Includes for pipe()
83 #if defined(_WIN32)
84 #include <fcntl.h>
85 #include <io.h>
86 #else
87 #include <unistd.h>
88 #endif
89 
90 namespace lldb_private {
91 class Address;
92 }
93 
94 using namespace lldb;
95 using namespace lldb_private;
96 
97 static lldb::user_id_t g_unique_id = 1;
98 static size_t g_debugger_event_thread_stack_bytes = 8 * 1024 * 1024;
99 
100 #pragma mark Static Functions
101 
102 typedef std::vector<DebuggerSP> DebuggerList;
103 static std::recursive_mutex *g_debugger_list_mutex_ptr =
104     nullptr; // NOTE: intentional leak to avoid issues with C++ destructor chain
105 static DebuggerList *g_debugger_list_ptr =
106     nullptr; // NOTE: intentional leak to avoid issues with C++ destructor chain
107 
108 static constexpr OptionEnumValueElement g_show_disassembly_enum_values[] = {
109     {
110         Debugger::eStopDisassemblyTypeNever,
111         "never",
112         "Never show disassembly when displaying a stop context.",
113     },
114     {
115         Debugger::eStopDisassemblyTypeNoDebugInfo,
116         "no-debuginfo",
117         "Show disassembly when there is no debug information.",
118     },
119     {
120         Debugger::eStopDisassemblyTypeNoSource,
121         "no-source",
122         "Show disassembly when there is no source information, or the source "
123         "file "
124         "is missing when displaying a stop context.",
125     },
126     {
127         Debugger::eStopDisassemblyTypeAlways,
128         "always",
129         "Always show disassembly when displaying a stop context.",
130     },
131 };
132 
133 static constexpr OptionEnumValueElement g_language_enumerators[] = {
134     {
135         eScriptLanguageNone,
136         "none",
137         "Disable scripting languages.",
138     },
139     {
140         eScriptLanguagePython,
141         "python",
142         "Select python as the default scripting language.",
143     },
144     {
145         eScriptLanguageDefault,
146         "default",
147         "Select the lldb default as the default scripting language.",
148     },
149 };
150 
151 static constexpr OptionEnumValueElement s_stop_show_column_values[] = {
152     {
153         eStopShowColumnAnsiOrCaret,
154         "ansi-or-caret",
155         "Highlight the stop column with ANSI terminal codes when color/ANSI "
156         "mode is enabled; otherwise, fall back to using a text-only caret (^) "
157         "as if \"caret-only\" mode was selected.",
158     },
159     {
160         eStopShowColumnAnsi,
161         "ansi",
162         "Highlight the stop column with ANSI terminal codes when running LLDB "
163         "with color/ANSI enabled.",
164     },
165     {
166         eStopShowColumnCaret,
167         "caret",
168         "Highlight the stop column with a caret character (^) underneath the "
169         "stop column. This method introduces a new line in source listings "
170         "that display thread stop locations.",
171     },
172     {
173         eStopShowColumnNone,
174         "none",
175         "Do not highlight the stop column.",
176     },
177 };
178 
179 #define LLDB_PROPERTIES_debugger
180 #include "CoreProperties.inc"
181 
182 enum {
183 #define LLDB_PROPERTIES_debugger
184 #include "CorePropertiesEnum.inc"
185 };
186 
187 LoadPluginCallbackType Debugger::g_load_plugin_callback = nullptr;
188 
189 Status Debugger::SetPropertyValue(const ExecutionContext *exe_ctx,
190                                   VarSetOperationType op,
191                                   llvm::StringRef property_path,
192                                   llvm::StringRef value) {
193   bool is_load_script =
194       (property_path == "target.load-script-from-symbol-file");
195   // These properties might change how we visualize data.
196   bool invalidate_data_vis = (property_path == "escape-non-printables");
197   invalidate_data_vis |=
198       (property_path == "target.max-zero-padding-in-float-format");
199   if (invalidate_data_vis) {
200     DataVisualization::ForceUpdate();
201   }
202 
203   TargetSP target_sp;
204   LoadScriptFromSymFile load_script_old_value;
205   if (is_load_script && exe_ctx->GetTargetSP()) {
206     target_sp = exe_ctx->GetTargetSP();
207     load_script_old_value =
208         target_sp->TargetProperties::GetLoadScriptFromSymbolFile();
209   }
210   Status error(Properties::SetPropertyValue(exe_ctx, op, property_path, value));
211   if (error.Success()) {
212     // FIXME it would be nice to have "on-change" callbacks for properties
213     if (property_path == g_debugger_properties[ePropertyPrompt].name) {
214       llvm::StringRef new_prompt = GetPrompt();
215       std::string str = lldb_private::ansi::FormatAnsiTerminalCodes(
216           new_prompt, GetUseColor());
217       if (str.length())
218         new_prompt = str;
219       GetCommandInterpreter().UpdatePrompt(new_prompt);
220       auto bytes = std::make_unique<EventDataBytes>(new_prompt);
221       auto prompt_change_event_sp = std::make_shared<Event>(
222           CommandInterpreter::eBroadcastBitResetPrompt, bytes.release());
223       GetCommandInterpreter().BroadcastEvent(prompt_change_event_sp);
224     } else if (property_path == g_debugger_properties[ePropertyUseColor].name) {
225       // use-color changed. Ping the prompt so it can reset the ansi terminal
226       // codes.
227       SetPrompt(GetPrompt());
228     } else if (property_path == g_debugger_properties[ePropertyUseSourceCache].name) {
229       // use-source-cache changed. Wipe out the cache contents if it was disabled.
230       if (!GetUseSourceCache()) {
231         m_source_file_cache.Clear();
232       }
233     } else if (is_load_script && target_sp &&
234                load_script_old_value == eLoadScriptFromSymFileWarn) {
235       if (target_sp->TargetProperties::GetLoadScriptFromSymbolFile() ==
236           eLoadScriptFromSymFileTrue) {
237         std::list<Status> errors;
238         StreamString feedback_stream;
239         if (!target_sp->LoadScriptingResources(errors, &feedback_stream)) {
240           Stream &s = GetErrorStream();
241           for (auto error : errors) {
242             s.Printf("%s\n", error.AsCString());
243           }
244           if (feedback_stream.GetSize())
245             s.PutCString(feedback_stream.GetString());
246         }
247       }
248     }
249   }
250   return error;
251 }
252 
253 bool Debugger::GetAutoConfirm() const {
254   const uint32_t idx = ePropertyAutoConfirm;
255   return m_collection_sp->GetPropertyAtIndexAsBoolean(
256       nullptr, idx, g_debugger_properties[idx].default_uint_value != 0);
257 }
258 
259 const FormatEntity::Entry *Debugger::GetDisassemblyFormat() const {
260   const uint32_t idx = ePropertyDisassemblyFormat;
261   return m_collection_sp->GetPropertyAtIndexAsFormatEntity(nullptr, idx);
262 }
263 
264 const FormatEntity::Entry *Debugger::GetFrameFormat() const {
265   const uint32_t idx = ePropertyFrameFormat;
266   return m_collection_sp->GetPropertyAtIndexAsFormatEntity(nullptr, idx);
267 }
268 
269 const FormatEntity::Entry *Debugger::GetFrameFormatUnique() const {
270   const uint32_t idx = ePropertyFrameFormatUnique;
271   return m_collection_sp->GetPropertyAtIndexAsFormatEntity(nullptr, idx);
272 }
273 
274 uint32_t Debugger::GetStopDisassemblyMaxSize() const {
275   const uint32_t idx = ePropertyStopDisassemblyMaxSize;
276   return m_collection_sp->GetPropertyAtIndexAsUInt64(
277       nullptr, idx, g_debugger_properties[idx].default_uint_value);
278 }
279 
280 bool Debugger::GetNotifyVoid() const {
281   const uint32_t idx = ePropertyNotiftVoid;
282   return m_collection_sp->GetPropertyAtIndexAsBoolean(
283       nullptr, idx, g_debugger_properties[idx].default_uint_value != 0);
284 }
285 
286 llvm::StringRef Debugger::GetPrompt() const {
287   const uint32_t idx = ePropertyPrompt;
288   return m_collection_sp->GetPropertyAtIndexAsString(
289       nullptr, idx, g_debugger_properties[idx].default_cstr_value);
290 }
291 
292 void Debugger::SetPrompt(llvm::StringRef p) {
293   const uint32_t idx = ePropertyPrompt;
294   m_collection_sp->SetPropertyAtIndexAsString(nullptr, idx, p);
295   llvm::StringRef new_prompt = GetPrompt();
296   std::string str =
297       lldb_private::ansi::FormatAnsiTerminalCodes(new_prompt, GetUseColor());
298   if (str.length())
299     new_prompt = str;
300   GetCommandInterpreter().UpdatePrompt(new_prompt);
301 }
302 
303 llvm::StringRef Debugger::GetReproducerPath() const {
304   auto &r = repro::Reproducer::Instance();
305   return r.GetReproducerPath().GetCString();
306 }
307 
308 const FormatEntity::Entry *Debugger::GetThreadFormat() const {
309   const uint32_t idx = ePropertyThreadFormat;
310   return m_collection_sp->GetPropertyAtIndexAsFormatEntity(nullptr, idx);
311 }
312 
313 const FormatEntity::Entry *Debugger::GetThreadStopFormat() const {
314   const uint32_t idx = ePropertyThreadStopFormat;
315   return m_collection_sp->GetPropertyAtIndexAsFormatEntity(nullptr, idx);
316 }
317 
318 lldb::ScriptLanguage Debugger::GetScriptLanguage() const {
319   const uint32_t idx = ePropertyScriptLanguage;
320   return (lldb::ScriptLanguage)m_collection_sp->GetPropertyAtIndexAsEnumeration(
321       nullptr, idx, g_debugger_properties[idx].default_uint_value);
322 }
323 
324 bool Debugger::SetScriptLanguage(lldb::ScriptLanguage script_lang) {
325   const uint32_t idx = ePropertyScriptLanguage;
326   return m_collection_sp->SetPropertyAtIndexAsEnumeration(nullptr, idx,
327                                                           script_lang);
328 }
329 
330 lldb::LanguageType Debugger::GetREPLLanguage() const {
331   const uint32_t idx = ePropertyREPLLanguage;
332   OptionValueLanguage *value =
333       m_collection_sp->GetPropertyAtIndexAsOptionValueLanguage(nullptr, idx);
334   if (value)
335     return value->GetCurrentValue();
336   return LanguageType();
337 }
338 
339 bool Debugger::SetREPLLanguage(lldb::LanguageType repl_lang) {
340   const uint32_t idx = ePropertyREPLLanguage;
341   return m_collection_sp->SetPropertyAtIndexAsLanguage(nullptr, idx, repl_lang);
342 }
343 
344 uint32_t Debugger::GetTerminalWidth() const {
345   const uint32_t idx = ePropertyTerminalWidth;
346   return m_collection_sp->GetPropertyAtIndexAsSInt64(
347       nullptr, idx, g_debugger_properties[idx].default_uint_value);
348 }
349 
350 bool Debugger::SetTerminalWidth(uint32_t term_width) {
351   if (auto handler_sp = m_io_handler_stack.Top())
352     handler_sp->TerminalSizeChanged();
353 
354   const uint32_t idx = ePropertyTerminalWidth;
355   return m_collection_sp->SetPropertyAtIndexAsSInt64(nullptr, idx, term_width);
356 }
357 
358 bool Debugger::GetUseExternalEditor() const {
359   const uint32_t idx = ePropertyUseExternalEditor;
360   return m_collection_sp->GetPropertyAtIndexAsBoolean(
361       nullptr, idx, g_debugger_properties[idx].default_uint_value != 0);
362 }
363 
364 bool Debugger::SetUseExternalEditor(bool b) {
365   const uint32_t idx = ePropertyUseExternalEditor;
366   return m_collection_sp->SetPropertyAtIndexAsBoolean(nullptr, idx, b);
367 }
368 
369 bool Debugger::GetUseColor() const {
370   const uint32_t idx = ePropertyUseColor;
371   return m_collection_sp->GetPropertyAtIndexAsBoolean(
372       nullptr, idx, g_debugger_properties[idx].default_uint_value != 0);
373 }
374 
375 bool Debugger::SetUseColor(bool b) {
376   const uint32_t idx = ePropertyUseColor;
377   bool ret = m_collection_sp->SetPropertyAtIndexAsBoolean(nullptr, idx, b);
378   SetPrompt(GetPrompt());
379   return ret;
380 }
381 
382 bool Debugger::GetShowProgress() const {
383   const uint32_t idx = ePropertyShowProgress;
384   return m_collection_sp->GetPropertyAtIndexAsBoolean(
385       nullptr, idx, g_debugger_properties[idx].default_uint_value != 0);
386 }
387 
388 llvm::StringRef Debugger::GetShowProgressAnsiPrefix() const {
389   const uint32_t idx = ePropertyShowProgressAnsiPrefix;
390   return m_collection_sp->GetPropertyAtIndexAsString(nullptr, idx, "");
391 }
392 
393 llvm::StringRef Debugger::GetShowProgressAnsiSuffix() const {
394   const uint32_t idx = ePropertyShowProgressAnsiSuffix;
395   return m_collection_sp->GetPropertyAtIndexAsString(nullptr, idx, "");
396 }
397 
398 bool Debugger::GetUseAutosuggestion() const {
399   const uint32_t idx = ePropertyShowAutosuggestion;
400   return m_collection_sp->GetPropertyAtIndexAsBoolean(
401       nullptr, idx, g_debugger_properties[idx].default_uint_value != 0);
402 }
403 
404 llvm::StringRef Debugger::GetAutosuggestionAnsiPrefix() const {
405   const uint32_t idx = ePropertyShowAutosuggestionAnsiPrefix;
406   return m_collection_sp->GetPropertyAtIndexAsString(nullptr, idx, "");
407 }
408 
409 llvm::StringRef Debugger::GetAutosuggestionAnsiSuffix() const {
410   const uint32_t idx = ePropertyShowAutosuggestionAnsiSuffix;
411   return m_collection_sp->GetPropertyAtIndexAsString(nullptr, idx, "");
412 }
413 
414 bool Debugger::GetUseSourceCache() const {
415   const uint32_t idx = ePropertyUseSourceCache;
416   return m_collection_sp->GetPropertyAtIndexAsBoolean(
417       nullptr, idx, g_debugger_properties[idx].default_uint_value != 0);
418 }
419 
420 bool Debugger::SetUseSourceCache(bool b) {
421   const uint32_t idx = ePropertyUseSourceCache;
422   bool ret = m_collection_sp->SetPropertyAtIndexAsBoolean(nullptr, idx, b);
423   if (!ret) {
424     m_source_file_cache.Clear();
425   }
426   return ret;
427 }
428 bool Debugger::GetHighlightSource() const {
429   const uint32_t idx = ePropertyHighlightSource;
430   return m_collection_sp->GetPropertyAtIndexAsBoolean(
431       nullptr, idx, g_debugger_properties[idx].default_uint_value);
432 }
433 
434 StopShowColumn Debugger::GetStopShowColumn() const {
435   const uint32_t idx = ePropertyStopShowColumn;
436   return (lldb::StopShowColumn)m_collection_sp->GetPropertyAtIndexAsEnumeration(
437       nullptr, idx, g_debugger_properties[idx].default_uint_value);
438 }
439 
440 llvm::StringRef Debugger::GetStopShowColumnAnsiPrefix() const {
441   const uint32_t idx = ePropertyStopShowColumnAnsiPrefix;
442   return m_collection_sp->GetPropertyAtIndexAsString(nullptr, idx, "");
443 }
444 
445 llvm::StringRef Debugger::GetStopShowColumnAnsiSuffix() const {
446   const uint32_t idx = ePropertyStopShowColumnAnsiSuffix;
447   return m_collection_sp->GetPropertyAtIndexAsString(nullptr, idx, "");
448 }
449 
450 llvm::StringRef Debugger::GetStopShowLineMarkerAnsiPrefix() const {
451   const uint32_t idx = ePropertyStopShowLineMarkerAnsiPrefix;
452   return m_collection_sp->GetPropertyAtIndexAsString(nullptr, idx, "");
453 }
454 
455 llvm::StringRef Debugger::GetStopShowLineMarkerAnsiSuffix() const {
456   const uint32_t idx = ePropertyStopShowLineMarkerAnsiSuffix;
457   return m_collection_sp->GetPropertyAtIndexAsString(nullptr, idx, "");
458 }
459 
460 uint32_t Debugger::GetStopSourceLineCount(bool before) const {
461   const uint32_t idx =
462       before ? ePropertyStopLineCountBefore : ePropertyStopLineCountAfter;
463   return m_collection_sp->GetPropertyAtIndexAsSInt64(
464       nullptr, idx, g_debugger_properties[idx].default_uint_value);
465 }
466 
467 Debugger::StopDisassemblyType Debugger::GetStopDisassemblyDisplay() const {
468   const uint32_t idx = ePropertyStopDisassemblyDisplay;
469   return (Debugger::StopDisassemblyType)
470       m_collection_sp->GetPropertyAtIndexAsEnumeration(
471           nullptr, idx, g_debugger_properties[idx].default_uint_value);
472 }
473 
474 uint32_t Debugger::GetDisassemblyLineCount() const {
475   const uint32_t idx = ePropertyStopDisassemblyCount;
476   return m_collection_sp->GetPropertyAtIndexAsSInt64(
477       nullptr, idx, g_debugger_properties[idx].default_uint_value);
478 }
479 
480 bool Debugger::GetAutoOneLineSummaries() const {
481   const uint32_t idx = ePropertyAutoOneLineSummaries;
482   return m_collection_sp->GetPropertyAtIndexAsBoolean(nullptr, idx, true);
483 }
484 
485 bool Debugger::GetEscapeNonPrintables() const {
486   const uint32_t idx = ePropertyEscapeNonPrintables;
487   return m_collection_sp->GetPropertyAtIndexAsBoolean(nullptr, idx, true);
488 }
489 
490 bool Debugger::GetAutoIndent() const {
491   const uint32_t idx = ePropertyAutoIndent;
492   return m_collection_sp->GetPropertyAtIndexAsBoolean(nullptr, idx, true);
493 }
494 
495 bool Debugger::SetAutoIndent(bool b) {
496   const uint32_t idx = ePropertyAutoIndent;
497   return m_collection_sp->SetPropertyAtIndexAsBoolean(nullptr, idx, b);
498 }
499 
500 bool Debugger::GetPrintDecls() const {
501   const uint32_t idx = ePropertyPrintDecls;
502   return m_collection_sp->GetPropertyAtIndexAsBoolean(nullptr, idx, true);
503 }
504 
505 bool Debugger::SetPrintDecls(bool b) {
506   const uint32_t idx = ePropertyPrintDecls;
507   return m_collection_sp->SetPropertyAtIndexAsBoolean(nullptr, idx, b);
508 }
509 
510 uint32_t Debugger::GetTabSize() const {
511   const uint32_t idx = ePropertyTabSize;
512   return m_collection_sp->GetPropertyAtIndexAsUInt64(
513       nullptr, idx, g_debugger_properties[idx].default_uint_value);
514 }
515 
516 bool Debugger::SetTabSize(uint32_t tab_size) {
517   const uint32_t idx = ePropertyTabSize;
518   return m_collection_sp->SetPropertyAtIndexAsUInt64(nullptr, idx, tab_size);
519 }
520 
521 #pragma mark Debugger
522 
523 // const DebuggerPropertiesSP &
524 // Debugger::GetSettings() const
525 //{
526 //    return m_properties_sp;
527 //}
528 //
529 
530 void Debugger::Initialize(LoadPluginCallbackType load_plugin_callback) {
531   assert(g_debugger_list_ptr == nullptr &&
532          "Debugger::Initialize called more than once!");
533   g_debugger_list_mutex_ptr = new std::recursive_mutex();
534   g_debugger_list_ptr = new DebuggerList();
535   g_load_plugin_callback = load_plugin_callback;
536 }
537 
538 void Debugger::Terminate() {
539   assert(g_debugger_list_ptr &&
540          "Debugger::Terminate called without a matching Debugger::Initialize!");
541 
542   if (g_debugger_list_ptr && g_debugger_list_mutex_ptr) {
543     // Clear our global list of debugger objects
544     {
545       std::lock_guard<std::recursive_mutex> guard(*g_debugger_list_mutex_ptr);
546       for (const auto &debugger : *g_debugger_list_ptr)
547         debugger->Clear();
548       g_debugger_list_ptr->clear();
549     }
550   }
551 }
552 
553 void Debugger::SettingsInitialize() { Target::SettingsInitialize(); }
554 
555 void Debugger::SettingsTerminate() { Target::SettingsTerminate(); }
556 
557 bool Debugger::LoadPlugin(const FileSpec &spec, Status &error) {
558   if (g_load_plugin_callback) {
559     llvm::sys::DynamicLibrary dynlib =
560         g_load_plugin_callback(shared_from_this(), spec, error);
561     if (dynlib.isValid()) {
562       m_loaded_plugins.push_back(dynlib);
563       return true;
564     }
565   } else {
566     // The g_load_plugin_callback is registered in SBDebugger::Initialize() and
567     // if the public API layer isn't available (code is linking against all of
568     // the internal LLDB static libraries), then we can't load plugins
569     error.SetErrorString("Public API layer is not available");
570   }
571   return false;
572 }
573 
574 static FileSystem::EnumerateDirectoryResult
575 LoadPluginCallback(void *baton, llvm::sys::fs::file_type ft,
576                    llvm::StringRef path) {
577   Status error;
578 
579   static ConstString g_dylibext(".dylib");
580   static ConstString g_solibext(".so");
581 
582   if (!baton)
583     return FileSystem::eEnumerateDirectoryResultQuit;
584 
585   Debugger *debugger = (Debugger *)baton;
586 
587   namespace fs = llvm::sys::fs;
588   // If we have a regular file, a symbolic link or unknown file type, try and
589   // process the file. We must handle unknown as sometimes the directory
590   // enumeration might be enumerating a file system that doesn't have correct
591   // file type information.
592   if (ft == fs::file_type::regular_file || ft == fs::file_type::symlink_file ||
593       ft == fs::file_type::type_unknown) {
594     FileSpec plugin_file_spec(path);
595     FileSystem::Instance().Resolve(plugin_file_spec);
596 
597     if (plugin_file_spec.GetFileNameExtension() != g_dylibext &&
598         plugin_file_spec.GetFileNameExtension() != g_solibext) {
599       return FileSystem::eEnumerateDirectoryResultNext;
600     }
601 
602     Status plugin_load_error;
603     debugger->LoadPlugin(plugin_file_spec, plugin_load_error);
604 
605     return FileSystem::eEnumerateDirectoryResultNext;
606   } else if (ft == fs::file_type::directory_file ||
607              ft == fs::file_type::symlink_file ||
608              ft == fs::file_type::type_unknown) {
609     // Try and recurse into anything that a directory or symbolic link. We must
610     // also do this for unknown as sometimes the directory enumeration might be
611     // enumerating a file system that doesn't have correct file type
612     // information.
613     return FileSystem::eEnumerateDirectoryResultEnter;
614   }
615 
616   return FileSystem::eEnumerateDirectoryResultNext;
617 }
618 
619 void Debugger::InstanceInitialize() {
620   const bool find_directories = true;
621   const bool find_files = true;
622   const bool find_other = true;
623   char dir_path[PATH_MAX];
624   if (FileSpec dir_spec = HostInfo::GetSystemPluginDir()) {
625     if (FileSystem::Instance().Exists(dir_spec) &&
626         dir_spec.GetPath(dir_path, sizeof(dir_path))) {
627       FileSystem::Instance().EnumerateDirectory(dir_path, find_directories,
628                                                 find_files, find_other,
629                                                 LoadPluginCallback, this);
630     }
631   }
632 
633   if (FileSpec dir_spec = HostInfo::GetUserPluginDir()) {
634     if (FileSystem::Instance().Exists(dir_spec) &&
635         dir_spec.GetPath(dir_path, sizeof(dir_path))) {
636       FileSystem::Instance().EnumerateDirectory(dir_path, find_directories,
637                                                 find_files, find_other,
638                                                 LoadPluginCallback, this);
639     }
640   }
641 
642   PluginManager::DebuggerInitialize(*this);
643 }
644 
645 DebuggerSP Debugger::CreateInstance(lldb::LogOutputCallback log_callback,
646                                     void *baton) {
647   DebuggerSP debugger_sp(new Debugger(log_callback, baton));
648   if (g_debugger_list_ptr && g_debugger_list_mutex_ptr) {
649     std::lock_guard<std::recursive_mutex> guard(*g_debugger_list_mutex_ptr);
650     g_debugger_list_ptr->push_back(debugger_sp);
651   }
652   debugger_sp->InstanceInitialize();
653   return debugger_sp;
654 }
655 
656 void Debugger::Destroy(DebuggerSP &debugger_sp) {
657   if (!debugger_sp)
658     return;
659 
660   CommandInterpreter &cmd_interpreter = debugger_sp->GetCommandInterpreter();
661 
662   if (cmd_interpreter.GetSaveSessionOnQuit()) {
663     CommandReturnObject result(debugger_sp->GetUseColor());
664     cmd_interpreter.SaveTranscript(result);
665     if (result.Succeeded())
666       debugger_sp->GetOutputStream() << result.GetOutputData() << '\n';
667     else
668       debugger_sp->GetErrorStream() << result.GetErrorData() << '\n';
669   }
670 
671   debugger_sp->Clear();
672 
673   if (g_debugger_list_ptr && g_debugger_list_mutex_ptr) {
674     std::lock_guard<std::recursive_mutex> guard(*g_debugger_list_mutex_ptr);
675     DebuggerList::iterator pos, end = g_debugger_list_ptr->end();
676     for (pos = g_debugger_list_ptr->begin(); pos != end; ++pos) {
677       if ((*pos).get() == debugger_sp.get()) {
678         g_debugger_list_ptr->erase(pos);
679         return;
680       }
681     }
682   }
683 }
684 
685 DebuggerSP Debugger::FindDebuggerWithInstanceName(ConstString instance_name) {
686   DebuggerSP debugger_sp;
687   if (g_debugger_list_ptr && g_debugger_list_mutex_ptr) {
688     std::lock_guard<std::recursive_mutex> guard(*g_debugger_list_mutex_ptr);
689     DebuggerList::iterator pos, end = g_debugger_list_ptr->end();
690     for (pos = g_debugger_list_ptr->begin(); pos != end; ++pos) {
691       if ((*pos)->m_instance_name == instance_name) {
692         debugger_sp = *pos;
693         break;
694       }
695     }
696   }
697   return debugger_sp;
698 }
699 
700 TargetSP Debugger::FindTargetWithProcessID(lldb::pid_t pid) {
701   TargetSP target_sp;
702   if (g_debugger_list_ptr && g_debugger_list_mutex_ptr) {
703     std::lock_guard<std::recursive_mutex> guard(*g_debugger_list_mutex_ptr);
704     DebuggerList::iterator pos, end = g_debugger_list_ptr->end();
705     for (pos = g_debugger_list_ptr->begin(); pos != end; ++pos) {
706       target_sp = (*pos)->GetTargetList().FindTargetWithProcessID(pid);
707       if (target_sp)
708         break;
709     }
710   }
711   return target_sp;
712 }
713 
714 TargetSP Debugger::FindTargetWithProcess(Process *process) {
715   TargetSP target_sp;
716   if (g_debugger_list_ptr && g_debugger_list_mutex_ptr) {
717     std::lock_guard<std::recursive_mutex> guard(*g_debugger_list_mutex_ptr);
718     DebuggerList::iterator pos, end = g_debugger_list_ptr->end();
719     for (pos = g_debugger_list_ptr->begin(); pos != end; ++pos) {
720       target_sp = (*pos)->GetTargetList().FindTargetWithProcess(process);
721       if (target_sp)
722         break;
723     }
724   }
725   return target_sp;
726 }
727 
728 ConstString Debugger::GetStaticBroadcasterClass() {
729   static ConstString class_name("lldb.debugger");
730   return class_name;
731 }
732 
733 Debugger::Debugger(lldb::LogOutputCallback log_callback, void *baton)
734     : UserID(g_unique_id++),
735       Properties(std::make_shared<OptionValueProperties>()),
736       m_input_file_sp(std::make_shared<NativeFile>(stdin, false)),
737       m_output_stream_sp(std::make_shared<StreamFile>(stdout, false)),
738       m_error_stream_sp(std::make_shared<StreamFile>(stderr, false)),
739       m_input_recorder(nullptr),
740       m_broadcaster_manager_sp(BroadcasterManager::MakeBroadcasterManager()),
741       m_terminal_state(), m_target_list(*this), m_platform_list(),
742       m_listener_sp(Listener::MakeListener("lldb.Debugger")),
743       m_source_manager_up(), m_source_file_cache(),
744       m_command_interpreter_up(
745           std::make_unique<CommandInterpreter>(*this, false)),
746       m_io_handler_stack(), m_instance_name(), m_loaded_plugins(),
747       m_event_handler_thread(), m_io_handler_thread(),
748       m_sync_broadcaster(nullptr, "lldb.debugger.sync"),
749       m_broadcaster(m_broadcaster_manager_sp,
750                     GetStaticBroadcasterClass().AsCString()),
751       m_forward_listener_sp(), m_clear_once() {
752   m_instance_name.SetString(llvm::formatv("debugger_{0}", GetID()).str());
753   if (log_callback)
754     m_log_callback_stream_sp =
755         std::make_shared<StreamCallback>(log_callback, baton);
756   m_command_interpreter_up->Initialize();
757   // Always add our default platform to the platform list
758   PlatformSP default_platform_sp(Platform::GetHostPlatform());
759   assert(default_platform_sp);
760   m_platform_list.Append(default_platform_sp, true);
761 
762   // Create the dummy target.
763   {
764     ArchSpec arch(Target::GetDefaultArchitecture());
765     if (!arch.IsValid())
766       arch = HostInfo::GetArchitecture();
767     assert(arch.IsValid() && "No valid default or host archspec");
768     const bool is_dummy_target = true;
769     m_dummy_target_sp.reset(
770         new Target(*this, arch, default_platform_sp, is_dummy_target));
771   }
772   assert(m_dummy_target_sp.get() && "Couldn't construct dummy target?");
773 
774   m_collection_sp->Initialize(g_debugger_properties);
775   m_collection_sp->AppendProperty(
776       ConstString("target"),
777       ConstString("Settings specify to debugging targets."), true,
778       Target::GetGlobalProperties().GetValueProperties());
779   m_collection_sp->AppendProperty(
780       ConstString("platform"), ConstString("Platform settings."), true,
781       Platform::GetGlobalPlatformProperties().GetValueProperties());
782   m_collection_sp->AppendProperty(
783       ConstString("symbols"), ConstString("Symbol lookup and cache settings."),
784       true, ModuleList::GetGlobalModuleListProperties().GetValueProperties());
785   if (m_command_interpreter_up) {
786     m_collection_sp->AppendProperty(
787         ConstString("interpreter"),
788         ConstString("Settings specify to the debugger's command interpreter."),
789         true, m_command_interpreter_up->GetValueProperties());
790   }
791   OptionValueSInt64 *term_width =
792       m_collection_sp->GetPropertyAtIndexAsOptionValueSInt64(
793           nullptr, ePropertyTerminalWidth);
794   term_width->SetMinimumValue(10);
795   term_width->SetMaximumValue(1024);
796 
797   // Turn off use-color if this is a dumb terminal.
798   const char *term = getenv("TERM");
799   if (term && !strcmp(term, "dumb"))
800     SetUseColor(false);
801   // Turn off use-color if we don't write to a terminal with color support.
802   if (!GetOutputFile().GetIsTerminalWithColors())
803     SetUseColor(false);
804 
805 #if defined(_WIN32) && defined(ENABLE_VIRTUAL_TERMINAL_PROCESSING)
806   // Enabling use of ANSI color codes because LLDB is using them to highlight
807   // text.
808   llvm::sys::Process::UseANSIEscapeCodes(true);
809 #endif
810 }
811 
812 Debugger::~Debugger() { Clear(); }
813 
814 void Debugger::Clear() {
815   // Make sure we call this function only once. With the C++ global destructor
816   // chain having a list of debuggers and with code that can be running on
817   // other threads, we need to ensure this doesn't happen multiple times.
818   //
819   // The following functions call Debugger::Clear():
820   //     Debugger::~Debugger();
821   //     static void Debugger::Destroy(lldb::DebuggerSP &debugger_sp);
822   //     static void Debugger::Terminate();
823   llvm::call_once(m_clear_once, [this]() {
824     ClearIOHandlers();
825     StopIOHandlerThread();
826     StopEventHandlerThread();
827     m_listener_sp->Clear();
828     for (TargetSP target_sp : m_target_list.Targets()) {
829       if (target_sp) {
830         if (ProcessSP process_sp = target_sp->GetProcessSP())
831           process_sp->Finalize();
832         target_sp->Destroy();
833       }
834     }
835     m_broadcaster_manager_sp->Clear();
836 
837     // Close the input file _before_ we close the input read communications
838     // class as it does NOT own the input file, our m_input_file does.
839     m_terminal_state.Clear();
840     GetInputFile().Close();
841 
842     m_command_interpreter_up->Clear();
843   });
844 }
845 
846 bool Debugger::GetCloseInputOnEOF() const {
847   //    return m_input_comm.GetCloseOnEOF();
848   return false;
849 }
850 
851 void Debugger::SetCloseInputOnEOF(bool b) {
852   //    m_input_comm.SetCloseOnEOF(b);
853 }
854 
855 bool Debugger::GetAsyncExecution() {
856   return !m_command_interpreter_up->GetSynchronous();
857 }
858 
859 void Debugger::SetAsyncExecution(bool async_execution) {
860   m_command_interpreter_up->SetSynchronous(!async_execution);
861 }
862 
863 repro::DataRecorder *Debugger::GetInputRecorder() { return m_input_recorder; }
864 
865 static inline int OpenPipe(int fds[2], std::size_t size) {
866 #ifdef _WIN32
867   return _pipe(fds, size, O_BINARY);
868 #else
869   (void)size;
870   return pipe(fds);
871 #endif
872 }
873 
874 Status Debugger::SetInputString(const char *data) {
875   Status result;
876   enum PIPES { READ, WRITE }; // Indexes for the read and write fds
877   int fds[2] = {-1, -1};
878 
879   if (data == nullptr) {
880     result.SetErrorString("String data is null");
881     return result;
882   }
883 
884   size_t size = strlen(data);
885   if (size == 0) {
886     result.SetErrorString("String data is empty");
887     return result;
888   }
889 
890   if (OpenPipe(fds, size) != 0) {
891     result.SetErrorString(
892         "can't create pipe file descriptors for LLDB commands");
893     return result;
894   }
895 
896   write(fds[WRITE], data, size);
897   // Close the write end of the pipe, so that the command interpreter will exit
898   // when it consumes all the data.
899   llvm::sys::Process::SafelyCloseFileDescriptor(fds[WRITE]);
900 
901   // Open the read file descriptor as a FILE * that we can return as an input
902   // handle.
903   FILE *commands_file = fdopen(fds[READ], "rb");
904   if (commands_file == nullptr) {
905     result.SetErrorStringWithFormat("fdopen(%i, \"rb\") failed (errno = %i) "
906                                     "when trying to open LLDB commands pipe",
907                                     fds[READ], errno);
908     llvm::sys::Process::SafelyCloseFileDescriptor(fds[READ]);
909     return result;
910   }
911 
912   return SetInputFile(
913       (FileSP)std::make_shared<NativeFile>(commands_file, true));
914 }
915 
916 Status Debugger::SetInputFile(FileSP file_sp) {
917   Status error;
918   repro::DataRecorder *recorder = nullptr;
919   if (repro::Generator *g = repro::Reproducer::Instance().GetGenerator())
920     recorder = g->GetOrCreate<repro::CommandProvider>().GetNewRecorder();
921 
922   static std::unique_ptr<repro::MultiLoader<repro::CommandProvider>> loader =
923       repro::MultiLoader<repro::CommandProvider>::Create(
924           repro::Reproducer::Instance().GetLoader());
925   if (loader) {
926     llvm::Optional<std::string> nextfile = loader->GetNextFile();
927     FILE *fh = nextfile ? FileSystem::Instance().Fopen(nextfile->c_str(), "r")
928                         : nullptr;
929     // FIXME Jonas Devlieghere: shouldn't this error be propagated out to the
930     // reproducer somehow if fh is NULL?
931     if (fh) {
932       file_sp = std::make_shared<NativeFile>(fh, true);
933     }
934   }
935 
936   if (!file_sp || !file_sp->IsValid()) {
937     error.SetErrorString("invalid file");
938     return error;
939   }
940 
941   SetInputFile(file_sp, recorder);
942   return error;
943 }
944 
945 void Debugger::SetInputFile(FileSP file_sp, repro::DataRecorder *recorder) {
946   assert(file_sp && file_sp->IsValid());
947   m_input_recorder = recorder;
948   m_input_file_sp = std::move(file_sp);
949   // Save away the terminal state if that is relevant, so that we can restore
950   // it in RestoreInputState.
951   SaveInputTerminalState();
952 }
953 
954 void Debugger::SetOutputFile(FileSP file_sp) {
955   assert(file_sp && file_sp->IsValid());
956   m_output_stream_sp = std::make_shared<StreamFile>(file_sp);
957 }
958 
959 void Debugger::SetErrorFile(FileSP file_sp) {
960   assert(file_sp && file_sp->IsValid());
961   m_error_stream_sp = std::make_shared<StreamFile>(file_sp);
962 }
963 
964 void Debugger::SaveInputTerminalState() {
965   int fd = GetInputFile().GetDescriptor();
966   if (fd != File::kInvalidDescriptor)
967     m_terminal_state.Save(fd, true);
968 }
969 
970 void Debugger::RestoreInputTerminalState() { m_terminal_state.Restore(); }
971 
972 ExecutionContext Debugger::GetSelectedExecutionContext() {
973   bool adopt_selected = true;
974   ExecutionContextRef exe_ctx_ref(GetSelectedTarget().get(), adopt_selected);
975   return ExecutionContext(exe_ctx_ref);
976 }
977 
978 void Debugger::DispatchInputInterrupt() {
979   std::lock_guard<std::recursive_mutex> guard(m_io_handler_stack.GetMutex());
980   IOHandlerSP reader_sp(m_io_handler_stack.Top());
981   if (reader_sp)
982     reader_sp->Interrupt();
983 }
984 
985 void Debugger::DispatchInputEndOfFile() {
986   std::lock_guard<std::recursive_mutex> guard(m_io_handler_stack.GetMutex());
987   IOHandlerSP reader_sp(m_io_handler_stack.Top());
988   if (reader_sp)
989     reader_sp->GotEOF();
990 }
991 
992 void Debugger::ClearIOHandlers() {
993   // The bottom input reader should be the main debugger input reader.  We do
994   // not want to close that one here.
995   std::lock_guard<std::recursive_mutex> guard(m_io_handler_stack.GetMutex());
996   while (m_io_handler_stack.GetSize() > 1) {
997     IOHandlerSP reader_sp(m_io_handler_stack.Top());
998     if (reader_sp)
999       PopIOHandler(reader_sp);
1000   }
1001 }
1002 
1003 void Debugger::RunIOHandlers() {
1004   IOHandlerSP reader_sp = m_io_handler_stack.Top();
1005   while (true) {
1006     if (!reader_sp)
1007       break;
1008 
1009     reader_sp->Run();
1010     {
1011       std::lock_guard<std::recursive_mutex> guard(
1012           m_io_handler_synchronous_mutex);
1013 
1014       // Remove all input readers that are done from the top of the stack
1015       while (true) {
1016         IOHandlerSP top_reader_sp = m_io_handler_stack.Top();
1017         if (top_reader_sp && top_reader_sp->GetIsDone())
1018           PopIOHandler(top_reader_sp);
1019         else
1020           break;
1021       }
1022       reader_sp = m_io_handler_stack.Top();
1023     }
1024   }
1025   ClearIOHandlers();
1026 }
1027 
1028 void Debugger::RunIOHandlerSync(const IOHandlerSP &reader_sp) {
1029   std::lock_guard<std::recursive_mutex> guard(m_io_handler_synchronous_mutex);
1030 
1031   PushIOHandler(reader_sp);
1032   IOHandlerSP top_reader_sp = reader_sp;
1033 
1034   while (top_reader_sp) {
1035     if (!top_reader_sp)
1036       break;
1037 
1038     top_reader_sp->Run();
1039 
1040     // Don't unwind past the starting point.
1041     if (top_reader_sp.get() == reader_sp.get()) {
1042       if (PopIOHandler(reader_sp))
1043         break;
1044     }
1045 
1046     // If we pushed new IO handlers, pop them if they're done or restart the
1047     // loop to run them if they're not.
1048     while (true) {
1049       top_reader_sp = m_io_handler_stack.Top();
1050       if (top_reader_sp && top_reader_sp->GetIsDone()) {
1051         PopIOHandler(top_reader_sp);
1052         // Don't unwind past the starting point.
1053         if (top_reader_sp.get() == reader_sp.get())
1054           return;
1055       } else {
1056         break;
1057       }
1058     }
1059   }
1060 }
1061 
1062 bool Debugger::IsTopIOHandler(const lldb::IOHandlerSP &reader_sp) {
1063   return m_io_handler_stack.IsTop(reader_sp);
1064 }
1065 
1066 bool Debugger::CheckTopIOHandlerTypes(IOHandler::Type top_type,
1067                                       IOHandler::Type second_top_type) {
1068   return m_io_handler_stack.CheckTopIOHandlerTypes(top_type, second_top_type);
1069 }
1070 
1071 void Debugger::PrintAsync(const char *s, size_t len, bool is_stdout) {
1072   lldb_private::StreamFile &stream =
1073       is_stdout ? GetOutputStream() : GetErrorStream();
1074   m_io_handler_stack.PrintAsync(&stream, s, len);
1075 }
1076 
1077 ConstString Debugger::GetTopIOHandlerControlSequence(char ch) {
1078   return m_io_handler_stack.GetTopIOHandlerControlSequence(ch);
1079 }
1080 
1081 const char *Debugger::GetIOHandlerCommandPrefix() {
1082   return m_io_handler_stack.GetTopIOHandlerCommandPrefix();
1083 }
1084 
1085 const char *Debugger::GetIOHandlerHelpPrologue() {
1086   return m_io_handler_stack.GetTopIOHandlerHelpPrologue();
1087 }
1088 
1089 bool Debugger::RemoveIOHandler(const IOHandlerSP &reader_sp) {
1090   return PopIOHandler(reader_sp);
1091 }
1092 
1093 void Debugger::RunIOHandlerAsync(const IOHandlerSP &reader_sp,
1094                                  bool cancel_top_handler) {
1095   PushIOHandler(reader_sp, cancel_top_handler);
1096 }
1097 
1098 void Debugger::AdoptTopIOHandlerFilesIfInvalid(FileSP &in, StreamFileSP &out,
1099                                                StreamFileSP &err) {
1100   // Before an IOHandler runs, it must have in/out/err streams. This function
1101   // is called when one ore more of the streams are nullptr. We use the top
1102   // input reader's in/out/err streams, or fall back to the debugger file
1103   // handles, or we fall back onto stdin/stdout/stderr as a last resort.
1104 
1105   std::lock_guard<std::recursive_mutex> guard(m_io_handler_stack.GetMutex());
1106   IOHandlerSP top_reader_sp(m_io_handler_stack.Top());
1107   // If no STDIN has been set, then set it appropriately
1108   if (!in || !in->IsValid()) {
1109     if (top_reader_sp)
1110       in = top_reader_sp->GetInputFileSP();
1111     else
1112       in = GetInputFileSP();
1113     // If there is nothing, use stdin
1114     if (!in)
1115       in = std::make_shared<NativeFile>(stdin, false);
1116   }
1117   // If no STDOUT has been set, then set it appropriately
1118   if (!out || !out->GetFile().IsValid()) {
1119     if (top_reader_sp)
1120       out = top_reader_sp->GetOutputStreamFileSP();
1121     else
1122       out = GetOutputStreamSP();
1123     // If there is nothing, use stdout
1124     if (!out)
1125       out = std::make_shared<StreamFile>(stdout, false);
1126   }
1127   // If no STDERR has been set, then set it appropriately
1128   if (!err || !err->GetFile().IsValid()) {
1129     if (top_reader_sp)
1130       err = top_reader_sp->GetErrorStreamFileSP();
1131     else
1132       err = GetErrorStreamSP();
1133     // If there is nothing, use stderr
1134     if (!err)
1135       err = std::make_shared<StreamFile>(stderr, false);
1136   }
1137 }
1138 
1139 void Debugger::PushIOHandler(const IOHandlerSP &reader_sp,
1140                              bool cancel_top_handler) {
1141   if (!reader_sp)
1142     return;
1143 
1144   std::lock_guard<std::recursive_mutex> guard(m_io_handler_stack.GetMutex());
1145 
1146   // Get the current top input reader...
1147   IOHandlerSP top_reader_sp(m_io_handler_stack.Top());
1148 
1149   // Don't push the same IO handler twice...
1150   if (reader_sp == top_reader_sp)
1151     return;
1152 
1153   // Push our new input reader
1154   m_io_handler_stack.Push(reader_sp);
1155   reader_sp->Activate();
1156 
1157   // Interrupt the top input reader to it will exit its Run() function and let
1158   // this new input reader take over
1159   if (top_reader_sp) {
1160     top_reader_sp->Deactivate();
1161     if (cancel_top_handler)
1162       top_reader_sp->Cancel();
1163   }
1164 }
1165 
1166 bool Debugger::PopIOHandler(const IOHandlerSP &pop_reader_sp) {
1167   if (!pop_reader_sp)
1168     return false;
1169 
1170   std::lock_guard<std::recursive_mutex> guard(m_io_handler_stack.GetMutex());
1171 
1172   // The reader on the stop of the stack is done, so let the next read on the
1173   // stack refresh its prompt and if there is one...
1174   if (m_io_handler_stack.IsEmpty())
1175     return false;
1176 
1177   IOHandlerSP reader_sp(m_io_handler_stack.Top());
1178 
1179   if (pop_reader_sp != reader_sp)
1180     return false;
1181 
1182   reader_sp->Deactivate();
1183   reader_sp->Cancel();
1184   m_io_handler_stack.Pop();
1185 
1186   reader_sp = m_io_handler_stack.Top();
1187   if (reader_sp)
1188     reader_sp->Activate();
1189 
1190   return true;
1191 }
1192 
1193 StreamSP Debugger::GetAsyncOutputStream() {
1194   return std::make_shared<StreamAsynchronousIO>(*this, true);
1195 }
1196 
1197 StreamSP Debugger::GetAsyncErrorStream() {
1198   return std::make_shared<StreamAsynchronousIO>(*this, false);
1199 }
1200 
1201 size_t Debugger::GetNumDebuggers() {
1202   if (g_debugger_list_ptr && g_debugger_list_mutex_ptr) {
1203     std::lock_guard<std::recursive_mutex> guard(*g_debugger_list_mutex_ptr);
1204     return g_debugger_list_ptr->size();
1205   }
1206   return 0;
1207 }
1208 
1209 lldb::DebuggerSP Debugger::GetDebuggerAtIndex(size_t index) {
1210   DebuggerSP debugger_sp;
1211 
1212   if (g_debugger_list_ptr && g_debugger_list_mutex_ptr) {
1213     std::lock_guard<std::recursive_mutex> guard(*g_debugger_list_mutex_ptr);
1214     if (index < g_debugger_list_ptr->size())
1215       debugger_sp = g_debugger_list_ptr->at(index);
1216   }
1217 
1218   return debugger_sp;
1219 }
1220 
1221 DebuggerSP Debugger::FindDebuggerWithID(lldb::user_id_t id) {
1222   DebuggerSP debugger_sp;
1223 
1224   if (g_debugger_list_ptr && g_debugger_list_mutex_ptr) {
1225     std::lock_guard<std::recursive_mutex> guard(*g_debugger_list_mutex_ptr);
1226     DebuggerList::iterator pos, end = g_debugger_list_ptr->end();
1227     for (pos = g_debugger_list_ptr->begin(); pos != end; ++pos) {
1228       if ((*pos)->GetID() == id) {
1229         debugger_sp = *pos;
1230         break;
1231       }
1232     }
1233   }
1234   return debugger_sp;
1235 }
1236 
1237 bool Debugger::FormatDisassemblerAddress(const FormatEntity::Entry *format,
1238                                          const SymbolContext *sc,
1239                                          const SymbolContext *prev_sc,
1240                                          const ExecutionContext *exe_ctx,
1241                                          const Address *addr, Stream &s) {
1242   FormatEntity::Entry format_entry;
1243 
1244   if (format == nullptr) {
1245     if (exe_ctx != nullptr && exe_ctx->HasTargetScope())
1246       format = exe_ctx->GetTargetRef().GetDebugger().GetDisassemblyFormat();
1247     if (format == nullptr) {
1248       FormatEntity::Parse("${addr}: ", format_entry);
1249       format = &format_entry;
1250     }
1251   }
1252   bool function_changed = false;
1253   bool initial_function = false;
1254   if (prev_sc && (prev_sc->function || prev_sc->symbol)) {
1255     if (sc && (sc->function || sc->symbol)) {
1256       if (prev_sc->symbol && sc->symbol) {
1257         if (!sc->symbol->Compare(prev_sc->symbol->GetName(),
1258                                  prev_sc->symbol->GetType())) {
1259           function_changed = true;
1260         }
1261       } else if (prev_sc->function && sc->function) {
1262         if (prev_sc->function->GetMangled() != sc->function->GetMangled()) {
1263           function_changed = true;
1264         }
1265       }
1266     }
1267   }
1268   // The first context on a list of instructions will have a prev_sc that has
1269   // no Function or Symbol -- if SymbolContext had an IsValid() method, it
1270   // would return false.  But we do get a prev_sc pointer.
1271   if ((sc && (sc->function || sc->symbol)) && prev_sc &&
1272       (prev_sc->function == nullptr && prev_sc->symbol == nullptr)) {
1273     initial_function = true;
1274   }
1275   return FormatEntity::Format(*format, s, sc, exe_ctx, addr, nullptr,
1276                               function_changed, initial_function);
1277 }
1278 
1279 void Debugger::SetLoggingCallback(lldb::LogOutputCallback log_callback,
1280                                   void *baton) {
1281   // For simplicity's sake, I am not going to deal with how to close down any
1282   // open logging streams, I just redirect everything from here on out to the
1283   // callback.
1284   m_log_callback_stream_sp =
1285       std::make_shared<StreamCallback>(log_callback, baton);
1286 }
1287 
1288 static void PrivateReportProgress(Debugger &debugger, uint64_t progress_id,
1289                                   const std::string &message,
1290                                   uint64_t completed, uint64_t total,
1291                                   bool is_debugger_specific) {
1292   // Only deliver progress events if we have any progress listeners.
1293   const uint32_t event_type = Debugger::eBroadcastBitProgress;
1294   if (!debugger.GetBroadcaster().EventTypeHasListeners(event_type))
1295     return;
1296   EventSP event_sp(new Event(
1297       event_type, new ProgressEventData(progress_id, message, completed, total,
1298                                         is_debugger_specific)));
1299   debugger.GetBroadcaster().BroadcastEvent(event_sp);
1300 }
1301 
1302 void Debugger::ReportProgress(uint64_t progress_id, const std::string &message,
1303                               uint64_t completed, uint64_t total,
1304                               llvm::Optional<lldb::user_id_t> debugger_id) {
1305   // Check if this progress is for a specific debugger.
1306   if (debugger_id.hasValue()) {
1307     // It is debugger specific, grab it and deliver the event if the debugger
1308     // still exists.
1309     DebuggerSP debugger_sp = FindDebuggerWithID(*debugger_id);
1310     if (debugger_sp)
1311       PrivateReportProgress(*debugger_sp, progress_id, message, completed,
1312                             total, /*is_debugger_specific*/ true);
1313     return;
1314   }
1315   // The progress event is not debugger specific, iterate over all debuggers
1316   // and deliver a progress event to each one.
1317   if (g_debugger_list_ptr && g_debugger_list_mutex_ptr) {
1318     std::lock_guard<std::recursive_mutex> guard(*g_debugger_list_mutex_ptr);
1319     DebuggerList::iterator pos, end = g_debugger_list_ptr->end();
1320     for (pos = g_debugger_list_ptr->begin(); pos != end; ++pos)
1321       PrivateReportProgress(*(*pos), progress_id, message, completed, total,
1322                             /*is_debugger_specific*/ false);
1323   }
1324 }
1325 
1326 bool Debugger::EnableLog(llvm::StringRef channel,
1327                          llvm::ArrayRef<const char *> categories,
1328                          llvm::StringRef log_file, uint32_t log_options,
1329                          llvm::raw_ostream &error_stream) {
1330   const bool should_close = true;
1331   const bool unbuffered = true;
1332 
1333   std::shared_ptr<llvm::raw_ostream> log_stream_sp;
1334   if (m_log_callback_stream_sp) {
1335     log_stream_sp = m_log_callback_stream_sp;
1336     // For now when using the callback mode you always get thread & timestamp.
1337     log_options |=
1338         LLDB_LOG_OPTION_PREPEND_TIMESTAMP | LLDB_LOG_OPTION_PREPEND_THREAD_NAME;
1339   } else if (log_file.empty()) {
1340     log_stream_sp = std::make_shared<llvm::raw_fd_ostream>(
1341         GetOutputFile().GetDescriptor(), !should_close, unbuffered);
1342   } else {
1343     auto pos = m_log_streams.find(log_file);
1344     if (pos != m_log_streams.end())
1345       log_stream_sp = pos->second.lock();
1346     if (!log_stream_sp) {
1347       File::OpenOptions flags =
1348           File::eOpenOptionWriteOnly | File::eOpenOptionCanCreate;
1349       if (log_options & LLDB_LOG_OPTION_APPEND)
1350         flags |= File::eOpenOptionAppend;
1351       else
1352         flags |= File::eOpenOptionTruncate;
1353       llvm::Expected<FileUP> file = FileSystem::Instance().Open(
1354           FileSpec(log_file), flags, lldb::eFilePermissionsFileDefault, false);
1355       if (!file) {
1356         error_stream << "Unable to open log file '" << log_file
1357                      << "': " << llvm::toString(file.takeError()) << "\n";
1358         return false;
1359       }
1360 
1361       log_stream_sp = std::make_shared<llvm::raw_fd_ostream>(
1362           (*file)->GetDescriptor(), should_close, unbuffered);
1363       m_log_streams[log_file] = log_stream_sp;
1364     }
1365   }
1366   assert(log_stream_sp);
1367 
1368   if (log_options == 0)
1369     log_options =
1370         LLDB_LOG_OPTION_PREPEND_THREAD_NAME | LLDB_LOG_OPTION_THREADSAFE;
1371 
1372   return Log::EnableLogChannel(log_stream_sp, log_options, channel, categories,
1373                                error_stream);
1374 }
1375 
1376 ScriptInterpreter *
1377 Debugger::GetScriptInterpreter(bool can_create,
1378                                llvm::Optional<lldb::ScriptLanguage> language) {
1379   std::lock_guard<std::recursive_mutex> locker(m_script_interpreter_mutex);
1380   lldb::ScriptLanguage script_language =
1381       language ? *language : GetScriptLanguage();
1382 
1383   if (!m_script_interpreters[script_language]) {
1384     if (!can_create)
1385       return nullptr;
1386     m_script_interpreters[script_language] =
1387         PluginManager::GetScriptInterpreterForLanguage(script_language, *this);
1388   }
1389 
1390   return m_script_interpreters[script_language].get();
1391 }
1392 
1393 SourceManager &Debugger::GetSourceManager() {
1394   if (!m_source_manager_up)
1395     m_source_manager_up = std::make_unique<SourceManager>(shared_from_this());
1396   return *m_source_manager_up;
1397 }
1398 
1399 // This function handles events that were broadcast by the process.
1400 void Debugger::HandleBreakpointEvent(const EventSP &event_sp) {
1401   using namespace lldb;
1402   const uint32_t event_type =
1403       Breakpoint::BreakpointEventData::GetBreakpointEventTypeFromEvent(
1404           event_sp);
1405 
1406   //    if (event_type & eBreakpointEventTypeAdded
1407   //        || event_type & eBreakpointEventTypeRemoved
1408   //        || event_type & eBreakpointEventTypeEnabled
1409   //        || event_type & eBreakpointEventTypeDisabled
1410   //        || event_type & eBreakpointEventTypeCommandChanged
1411   //        || event_type & eBreakpointEventTypeConditionChanged
1412   //        || event_type & eBreakpointEventTypeIgnoreChanged
1413   //        || event_type & eBreakpointEventTypeLocationsResolved)
1414   //    {
1415   //        // Don't do anything about these events, since the breakpoint
1416   //        commands already echo these actions.
1417   //    }
1418   //
1419   if (event_type & eBreakpointEventTypeLocationsAdded) {
1420     uint32_t num_new_locations =
1421         Breakpoint::BreakpointEventData::GetNumBreakpointLocationsFromEvent(
1422             event_sp);
1423     if (num_new_locations > 0) {
1424       BreakpointSP breakpoint =
1425           Breakpoint::BreakpointEventData::GetBreakpointFromEvent(event_sp);
1426       StreamSP output_sp(GetAsyncOutputStream());
1427       if (output_sp) {
1428         output_sp->Printf("%d location%s added to breakpoint %d\n",
1429                           num_new_locations, num_new_locations == 1 ? "" : "s",
1430                           breakpoint->GetID());
1431         output_sp->Flush();
1432       }
1433     }
1434   }
1435   //    else if (event_type & eBreakpointEventTypeLocationsRemoved)
1436   //    {
1437   //        // These locations just get disabled, not sure it is worth spamming
1438   //        folks about this on the command line.
1439   //    }
1440   //    else if (event_type & eBreakpointEventTypeLocationsResolved)
1441   //    {
1442   //        // This might be an interesting thing to note, but I'm going to
1443   //        leave it quiet for now, it just looked noisy.
1444   //    }
1445 }
1446 
1447 void Debugger::FlushProcessOutput(Process &process, bool flush_stdout,
1448                                   bool flush_stderr) {
1449   const auto &flush = [&](Stream &stream,
1450                           size_t (Process::*get)(char *, size_t, Status &)) {
1451     Status error;
1452     size_t len;
1453     char buffer[1024];
1454     while ((len = (process.*get)(buffer, sizeof(buffer), error)) > 0)
1455       stream.Write(buffer, len);
1456     stream.Flush();
1457   };
1458 
1459   std::lock_guard<std::mutex> guard(m_output_flush_mutex);
1460   if (flush_stdout)
1461     flush(*GetAsyncOutputStream(), &Process::GetSTDOUT);
1462   if (flush_stderr)
1463     flush(*GetAsyncErrorStream(), &Process::GetSTDERR);
1464 }
1465 
1466 // This function handles events that were broadcast by the process.
1467 void Debugger::HandleProcessEvent(const EventSP &event_sp) {
1468   using namespace lldb;
1469   const uint32_t event_type = event_sp->GetType();
1470   ProcessSP process_sp =
1471       (event_type == Process::eBroadcastBitStructuredData)
1472           ? EventDataStructuredData::GetProcessFromEvent(event_sp.get())
1473           : Process::ProcessEventData::GetProcessFromEvent(event_sp.get());
1474 
1475   StreamSP output_stream_sp = GetAsyncOutputStream();
1476   StreamSP error_stream_sp = GetAsyncErrorStream();
1477   const bool gui_enabled = IsForwardingEvents();
1478 
1479   if (!gui_enabled) {
1480     bool pop_process_io_handler = false;
1481     assert(process_sp);
1482 
1483     bool state_is_stopped = false;
1484     const bool got_state_changed =
1485         (event_type & Process::eBroadcastBitStateChanged) != 0;
1486     const bool got_stdout = (event_type & Process::eBroadcastBitSTDOUT) != 0;
1487     const bool got_stderr = (event_type & Process::eBroadcastBitSTDERR) != 0;
1488     const bool got_structured_data =
1489         (event_type & Process::eBroadcastBitStructuredData) != 0;
1490 
1491     if (got_state_changed) {
1492       StateType event_state =
1493           Process::ProcessEventData::GetStateFromEvent(event_sp.get());
1494       state_is_stopped = StateIsStoppedState(event_state, false);
1495     }
1496 
1497     // Display running state changes first before any STDIO
1498     if (got_state_changed && !state_is_stopped) {
1499       Process::HandleProcessStateChangedEvent(event_sp, output_stream_sp.get(),
1500                                               pop_process_io_handler);
1501     }
1502 
1503     // Now display STDOUT and STDERR
1504     FlushProcessOutput(*process_sp, got_stdout || got_state_changed,
1505                        got_stderr || got_state_changed);
1506 
1507     // Give structured data events an opportunity to display.
1508     if (got_structured_data) {
1509       StructuredDataPluginSP plugin_sp =
1510           EventDataStructuredData::GetPluginFromEvent(event_sp.get());
1511       if (plugin_sp) {
1512         auto structured_data_sp =
1513             EventDataStructuredData::GetObjectFromEvent(event_sp.get());
1514         if (output_stream_sp) {
1515           StreamString content_stream;
1516           Status error =
1517               plugin_sp->GetDescription(structured_data_sp, content_stream);
1518           if (error.Success()) {
1519             if (!content_stream.GetString().empty()) {
1520               // Add newline.
1521               content_stream.PutChar('\n');
1522               content_stream.Flush();
1523 
1524               // Print it.
1525               output_stream_sp->PutCString(content_stream.GetString());
1526             }
1527           } else {
1528             error_stream_sp->Format("Failed to print structured "
1529                                     "data with plugin {0}: {1}",
1530                                     plugin_sp->GetPluginName(), error);
1531           }
1532         }
1533       }
1534     }
1535 
1536     // Now display any stopped state changes after any STDIO
1537     if (got_state_changed && state_is_stopped) {
1538       Process::HandleProcessStateChangedEvent(event_sp, output_stream_sp.get(),
1539                                               pop_process_io_handler);
1540     }
1541 
1542     output_stream_sp->Flush();
1543     error_stream_sp->Flush();
1544 
1545     if (pop_process_io_handler)
1546       process_sp->PopProcessIOHandler();
1547   }
1548 }
1549 
1550 void Debugger::HandleThreadEvent(const EventSP &event_sp) {
1551   // At present the only thread event we handle is the Frame Changed event, and
1552   // all we do for that is just reprint the thread status for that thread.
1553   using namespace lldb;
1554   const uint32_t event_type = event_sp->GetType();
1555   const bool stop_format = true;
1556   if (event_type == Thread::eBroadcastBitStackChanged ||
1557       event_type == Thread::eBroadcastBitThreadSelected) {
1558     ThreadSP thread_sp(
1559         Thread::ThreadEventData::GetThreadFromEvent(event_sp.get()));
1560     if (thread_sp) {
1561       thread_sp->GetStatus(*GetAsyncOutputStream(), 0, 1, 1, stop_format);
1562     }
1563   }
1564 }
1565 
1566 bool Debugger::IsForwardingEvents() { return (bool)m_forward_listener_sp; }
1567 
1568 void Debugger::EnableForwardEvents(const ListenerSP &listener_sp) {
1569   m_forward_listener_sp = listener_sp;
1570 }
1571 
1572 void Debugger::CancelForwardEvents(const ListenerSP &listener_sp) {
1573   m_forward_listener_sp.reset();
1574 }
1575 
1576 lldb::thread_result_t Debugger::DefaultEventHandler() {
1577   ListenerSP listener_sp(GetListener());
1578   ConstString broadcaster_class_target(Target::GetStaticBroadcasterClass());
1579   ConstString broadcaster_class_process(Process::GetStaticBroadcasterClass());
1580   ConstString broadcaster_class_thread(Thread::GetStaticBroadcasterClass());
1581   BroadcastEventSpec target_event_spec(broadcaster_class_target,
1582                                        Target::eBroadcastBitBreakpointChanged);
1583 
1584   BroadcastEventSpec process_event_spec(
1585       broadcaster_class_process,
1586       Process::eBroadcastBitStateChanged | Process::eBroadcastBitSTDOUT |
1587           Process::eBroadcastBitSTDERR | Process::eBroadcastBitStructuredData);
1588 
1589   BroadcastEventSpec thread_event_spec(broadcaster_class_thread,
1590                                        Thread::eBroadcastBitStackChanged |
1591                                            Thread::eBroadcastBitThreadSelected);
1592 
1593   listener_sp->StartListeningForEventSpec(m_broadcaster_manager_sp,
1594                                           target_event_spec);
1595   listener_sp->StartListeningForEventSpec(m_broadcaster_manager_sp,
1596                                           process_event_spec);
1597   listener_sp->StartListeningForEventSpec(m_broadcaster_manager_sp,
1598                                           thread_event_spec);
1599   listener_sp->StartListeningForEvents(
1600       m_command_interpreter_up.get(),
1601       CommandInterpreter::eBroadcastBitQuitCommandReceived |
1602           CommandInterpreter::eBroadcastBitAsynchronousOutputData |
1603           CommandInterpreter::eBroadcastBitAsynchronousErrorData);
1604 
1605   listener_sp->StartListeningForEvents(&m_broadcaster,
1606                                        Debugger::eBroadcastBitProgress);
1607 
1608   // Let the thread that spawned us know that we have started up and that we
1609   // are now listening to all required events so no events get missed
1610   m_sync_broadcaster.BroadcastEvent(eBroadcastBitEventThreadIsListening);
1611 
1612   bool done = false;
1613   while (!done) {
1614     EventSP event_sp;
1615     if (listener_sp->GetEvent(event_sp, llvm::None)) {
1616       if (event_sp) {
1617         Broadcaster *broadcaster = event_sp->GetBroadcaster();
1618         if (broadcaster) {
1619           uint32_t event_type = event_sp->GetType();
1620           ConstString broadcaster_class(broadcaster->GetBroadcasterClass());
1621           if (broadcaster_class == broadcaster_class_process) {
1622             HandleProcessEvent(event_sp);
1623           } else if (broadcaster_class == broadcaster_class_target) {
1624             if (Breakpoint::BreakpointEventData::GetEventDataFromEvent(
1625                     event_sp.get())) {
1626               HandleBreakpointEvent(event_sp);
1627             }
1628           } else if (broadcaster_class == broadcaster_class_thread) {
1629             HandleThreadEvent(event_sp);
1630           } else if (broadcaster == m_command_interpreter_up.get()) {
1631             if (event_type &
1632                 CommandInterpreter::eBroadcastBitQuitCommandReceived) {
1633               done = true;
1634             } else if (event_type &
1635                        CommandInterpreter::eBroadcastBitAsynchronousErrorData) {
1636               const char *data = static_cast<const char *>(
1637                   EventDataBytes::GetBytesFromEvent(event_sp.get()));
1638               if (data && data[0]) {
1639                 StreamSP error_sp(GetAsyncErrorStream());
1640                 if (error_sp) {
1641                   error_sp->PutCString(data);
1642                   error_sp->Flush();
1643                 }
1644               }
1645             } else if (event_type & CommandInterpreter::
1646                                         eBroadcastBitAsynchronousOutputData) {
1647               const char *data = static_cast<const char *>(
1648                   EventDataBytes::GetBytesFromEvent(event_sp.get()));
1649               if (data && data[0]) {
1650                 StreamSP output_sp(GetAsyncOutputStream());
1651                 if (output_sp) {
1652                   output_sp->PutCString(data);
1653                   output_sp->Flush();
1654                 }
1655               }
1656             }
1657           } else if (broadcaster == &m_broadcaster) {
1658             if (event_type & Debugger::eBroadcastBitProgress)
1659               HandleProgressEvent(event_sp);
1660           }
1661         }
1662 
1663         if (m_forward_listener_sp)
1664           m_forward_listener_sp->AddEvent(event_sp);
1665       }
1666     }
1667   }
1668   return {};
1669 }
1670 
1671 bool Debugger::StartEventHandlerThread() {
1672   if (!m_event_handler_thread.IsJoinable()) {
1673     // We must synchronize with the DefaultEventHandler() thread to ensure it
1674     // is up and running and listening to events before we return from this
1675     // function. We do this by listening to events for the
1676     // eBroadcastBitEventThreadIsListening from the m_sync_broadcaster
1677     ConstString full_name("lldb.debugger.event-handler");
1678     ListenerSP listener_sp(Listener::MakeListener(full_name.AsCString()));
1679     listener_sp->StartListeningForEvents(&m_sync_broadcaster,
1680                                          eBroadcastBitEventThreadIsListening);
1681 
1682     llvm::StringRef thread_name =
1683         full_name.GetLength() < llvm::get_max_thread_name_length()
1684             ? full_name.GetStringRef()
1685             : "dbg.evt-handler";
1686 
1687     // Use larger 8MB stack for this thread
1688     llvm::Expected<HostThread> event_handler_thread =
1689         ThreadLauncher::LaunchThread(
1690             thread_name, [this] { return DefaultEventHandler(); },
1691             g_debugger_event_thread_stack_bytes);
1692 
1693     if (event_handler_thread) {
1694       m_event_handler_thread = *event_handler_thread;
1695     } else {
1696       LLDB_LOG(GetLog(LLDBLog::Host), "failed to launch host thread: {}",
1697                llvm::toString(event_handler_thread.takeError()));
1698     }
1699 
1700     // Make sure DefaultEventHandler() is running and listening to events
1701     // before we return from this function. We are only listening for events of
1702     // type eBroadcastBitEventThreadIsListening so we don't need to check the
1703     // event, we just need to wait an infinite amount of time for it (nullptr
1704     // timeout as the first parameter)
1705     lldb::EventSP event_sp;
1706     listener_sp->GetEvent(event_sp, llvm::None);
1707   }
1708   return m_event_handler_thread.IsJoinable();
1709 }
1710 
1711 void Debugger::StopEventHandlerThread() {
1712   if (m_event_handler_thread.IsJoinable()) {
1713     GetCommandInterpreter().BroadcastEvent(
1714         CommandInterpreter::eBroadcastBitQuitCommandReceived);
1715     m_event_handler_thread.Join(nullptr);
1716   }
1717 }
1718 
1719 lldb::thread_result_t Debugger::IOHandlerThread() {
1720   RunIOHandlers();
1721   StopEventHandlerThread();
1722   return {};
1723 }
1724 
1725 void Debugger::HandleProgressEvent(const lldb::EventSP &event_sp) {
1726   auto *data = ProgressEventData::GetEventDataFromEvent(event_sp.get());
1727   if (!data)
1728     return;
1729 
1730   // Do some bookkeeping for the current event, regardless of whether we're
1731   // going to show the progress.
1732   const uint64_t id = data->GetID();
1733   if (m_current_event_id) {
1734     if (id != *m_current_event_id)
1735       return;
1736     if (data->GetCompleted())
1737       m_current_event_id.reset();
1738   } else {
1739     m_current_event_id = id;
1740   }
1741 
1742   // Decide whether we actually are going to show the progress. This decision
1743   // can change between iterations so check it inside the loop.
1744   if (!GetShowProgress())
1745     return;
1746 
1747   // Determine whether the current output file is an interactive terminal with
1748   // color support. We assume that if we support ANSI escape codes we support
1749   // vt100 escape codes.
1750   File &output = GetOutputFile();
1751   if (!output.GetIsInteractive() || !output.GetIsTerminalWithColors())
1752     return;
1753 
1754   // Print over previous line, if any.
1755   output.Printf("\r");
1756 
1757   if (data->GetCompleted()) {
1758     // Clear the current line.
1759     output.Printf("\x1B[2K");
1760     output.Flush();
1761     return;
1762   }
1763 
1764   const bool use_color = GetUseColor();
1765   llvm::StringRef ansi_prefix = GetShowProgressAnsiPrefix();
1766   if (!ansi_prefix.empty())
1767     output.Printf(
1768         "%s", ansi::FormatAnsiTerminalCodes(ansi_prefix, use_color).c_str());
1769 
1770   // Print the progress message.
1771   std::string message = data->GetMessage();
1772   if (data->GetTotal() != UINT64_MAX) {
1773     output.Printf("[%" PRIu64 "/%" PRIu64 "] %s...", data->GetCompleted(), data->GetTotal(),
1774                   message.c_str());
1775   } else {
1776     output.Printf("%s...", message.c_str());
1777   }
1778 
1779   llvm::StringRef ansi_suffix = GetShowProgressAnsiSuffix();
1780   if (!ansi_suffix.empty())
1781     output.Printf(
1782         "%s", ansi::FormatAnsiTerminalCodes(ansi_suffix, use_color).c_str());
1783 
1784   // Clear until the end of the line.
1785   output.Printf("\x1B[K\r");
1786 
1787   // Flush the output.
1788   output.Flush();
1789 }
1790 
1791 bool Debugger::HasIOHandlerThread() { return m_io_handler_thread.IsJoinable(); }
1792 
1793 bool Debugger::StartIOHandlerThread() {
1794   if (!m_io_handler_thread.IsJoinable()) {
1795     llvm::Expected<HostThread> io_handler_thread = ThreadLauncher::LaunchThread(
1796         "lldb.debugger.io-handler", [this] { return IOHandlerThread(); },
1797         8 * 1024 * 1024); // Use larger 8MB stack for this thread
1798     if (io_handler_thread) {
1799       m_io_handler_thread = *io_handler_thread;
1800     } else {
1801       LLDB_LOG(GetLog(LLDBLog::Host), "failed to launch host thread: {}",
1802                llvm::toString(io_handler_thread.takeError()));
1803     }
1804   }
1805   return m_io_handler_thread.IsJoinable();
1806 }
1807 
1808 void Debugger::StopIOHandlerThread() {
1809   if (m_io_handler_thread.IsJoinable()) {
1810     GetInputFile().Close();
1811     m_io_handler_thread.Join(nullptr);
1812   }
1813 }
1814 
1815 void Debugger::JoinIOHandlerThread() {
1816   if (HasIOHandlerThread()) {
1817     thread_result_t result;
1818     m_io_handler_thread.Join(&result);
1819     m_io_handler_thread = LLDB_INVALID_HOST_THREAD;
1820   }
1821 }
1822 
1823 Target &Debugger::GetSelectedOrDummyTarget(bool prefer_dummy) {
1824   if (!prefer_dummy) {
1825     if (TargetSP target = m_target_list.GetSelectedTarget())
1826       return *target;
1827   }
1828   return GetDummyTarget();
1829 }
1830 
1831 Status Debugger::RunREPL(LanguageType language, const char *repl_options) {
1832   Status err;
1833   FileSpec repl_executable;
1834 
1835   if (language == eLanguageTypeUnknown)
1836     language = GetREPLLanguage();
1837 
1838   if (language == eLanguageTypeUnknown) {
1839     LanguageSet repl_languages = Language::GetLanguagesSupportingREPLs();
1840 
1841     if (auto single_lang = repl_languages.GetSingularLanguage()) {
1842       language = *single_lang;
1843     } else if (repl_languages.Empty()) {
1844       err.SetErrorString(
1845           "LLDB isn't configured with REPL support for any languages.");
1846       return err;
1847     } else {
1848       err.SetErrorString(
1849           "Multiple possible REPL languages.  Please specify a language.");
1850       return err;
1851     }
1852   }
1853 
1854   Target *const target =
1855       nullptr; // passing in an empty target means the REPL must create one
1856 
1857   REPLSP repl_sp(REPL::Create(err, language, this, target, repl_options));
1858 
1859   if (!err.Success()) {
1860     return err;
1861   }
1862 
1863   if (!repl_sp) {
1864     err.SetErrorStringWithFormat("couldn't find a REPL for %s",
1865                                  Language::GetNameForLanguageType(language));
1866     return err;
1867   }
1868 
1869   repl_sp->SetCompilerOptions(repl_options);
1870   repl_sp->RunLoop();
1871 
1872   return err;
1873 }
1874