1 //===-- ScriptInterpreterLua.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 "ScriptInterpreterLua.h" 10 #include "Lua.h" 11 #include "lldb/Breakpoint/StoppointCallbackContext.h" 12 #include "lldb/Core/Debugger.h" 13 #include "lldb/Core/PluginManager.h" 14 #include "lldb/Core/StreamFile.h" 15 #include "lldb/Interpreter/CommandReturnObject.h" 16 #include "lldb/Target/ExecutionContext.h" 17 #include "lldb/Utility/Stream.h" 18 #include "lldb/Utility/StringList.h" 19 #include "lldb/Utility/Timer.h" 20 #include "llvm/ADT/StringRef.h" 21 #include "llvm/Support/FormatAdapters.h" 22 #include <memory> 23 #include <vector> 24 25 using namespace lldb; 26 using namespace lldb_private; 27 28 LLDB_PLUGIN_DEFINE(ScriptInterpreterLua) 29 30 enum ActiveIOHandler { 31 eIOHandlerNone, 32 eIOHandlerBreakpoint, 33 eIOHandlerWatchpoint 34 }; 35 36 class IOHandlerLuaInterpreter : public IOHandlerDelegate, 37 public IOHandlerEditline { 38 public: 39 IOHandlerLuaInterpreter(Debugger &debugger, 40 ScriptInterpreterLua &script_interpreter, 41 ActiveIOHandler active_io_handler = eIOHandlerNone) 42 : IOHandlerEditline(debugger, IOHandler::Type::LuaInterpreter, "lua", 43 ">>> ", "..> ", true, debugger.GetUseColor(), 0, 44 *this, nullptr), 45 m_script_interpreter(script_interpreter), 46 m_active_io_handler(active_io_handler) { 47 llvm::cantFail(m_script_interpreter.GetLua().ChangeIO( 48 debugger.GetOutputFile().GetStream(), 49 debugger.GetErrorFile().GetStream())); 50 llvm::cantFail(m_script_interpreter.EnterSession(debugger.GetID())); 51 } 52 53 ~IOHandlerLuaInterpreter() override { 54 llvm::cantFail(m_script_interpreter.LeaveSession()); 55 } 56 57 void IOHandlerActivated(IOHandler &io_handler, bool interactive) override { 58 const char *instructions = nullptr; 59 switch (m_active_io_handler) { 60 case eIOHandlerNone: 61 case eIOHandlerWatchpoint: 62 break; 63 case eIOHandlerBreakpoint: 64 instructions = "Enter your Lua command(s). Type 'quit' to end.\n" 65 "The commands are compiled as the body of the following " 66 "Lua function\n" 67 "function (frame, bp_loc, ...) end\n"; 68 SetPrompt(llvm::StringRef("..> ")); 69 break; 70 } 71 if (instructions == nullptr) 72 return; 73 if (interactive) 74 *io_handler.GetOutputStreamFileSP() << instructions; 75 } 76 77 bool IOHandlerIsInputComplete(IOHandler &io_handler, 78 StringList &lines) override { 79 size_t last = lines.GetSize() - 1; 80 if (IsQuitCommand(lines.GetStringAtIndex(last))) { 81 if (m_active_io_handler == eIOHandlerBreakpoint) 82 lines.DeleteStringAtIndex(last); 83 return true; 84 } 85 StreamString str; 86 lines.Join("\n", str); 87 if (llvm::Error E = 88 m_script_interpreter.GetLua().CheckSyntax(str.GetString())) { 89 std::string error_str = toString(std::move(E)); 90 // Lua always errors out to incomplete code with '<eof>' 91 return error_str.find("<eof>") == std::string::npos; 92 } 93 // The breakpoint handler only exits with a explicit 'quit' 94 return m_active_io_handler != eIOHandlerBreakpoint; 95 } 96 97 void IOHandlerInputComplete(IOHandler &io_handler, 98 std::string &data) override { 99 switch (m_active_io_handler) { 100 case eIOHandlerBreakpoint: { 101 auto *bp_options_vec = static_cast<std::vector<BreakpointOptions *> *>( 102 io_handler.GetUserData()); 103 for (auto *bp_options : *bp_options_vec) { 104 Status error = m_script_interpreter.SetBreakpointCommandCallback( 105 bp_options, data.c_str()); 106 if (error.Fail()) 107 *io_handler.GetErrorStreamFileSP() << error.AsCString() << '\n'; 108 } 109 io_handler.SetIsDone(true); 110 } break; 111 case eIOHandlerWatchpoint: 112 io_handler.SetIsDone(true); 113 break; 114 case eIOHandlerNone: 115 if (IsQuitCommand(data)) { 116 io_handler.SetIsDone(true); 117 return; 118 } 119 if (llvm::Error error = m_script_interpreter.GetLua().Run(data)) 120 *io_handler.GetErrorStreamFileSP() << toString(std::move(error)); 121 break; 122 } 123 } 124 125 private: 126 ScriptInterpreterLua &m_script_interpreter; 127 ActiveIOHandler m_active_io_handler; 128 129 bool IsQuitCommand(llvm::StringRef cmd) { return cmd.rtrim() == "quit"; } 130 }; 131 132 ScriptInterpreterLua::ScriptInterpreterLua(Debugger &debugger) 133 : ScriptInterpreter(debugger, eScriptLanguageLua), 134 m_lua(std::make_unique<Lua>()) {} 135 136 ScriptInterpreterLua::~ScriptInterpreterLua() {} 137 138 bool ScriptInterpreterLua::ExecuteOneLine(llvm::StringRef command, 139 CommandReturnObject *result, 140 const ExecuteScriptOptions &options) { 141 if (command.empty()) { 142 if (result) 143 result->AppendError("empty command passed to lua\n"); 144 return false; 145 } 146 147 llvm::Expected<std::unique_ptr<ScriptInterpreterIORedirect>> 148 io_redirect_or_error = ScriptInterpreterIORedirect::Create( 149 options.GetEnableIO(), m_debugger, result); 150 if (!io_redirect_or_error) { 151 if (result) 152 result->AppendErrorWithFormatv( 153 "failed to redirect I/O: {0}\n", 154 llvm::fmt_consume(io_redirect_or_error.takeError())); 155 else 156 llvm::consumeError(io_redirect_or_error.takeError()); 157 return false; 158 } 159 160 ScriptInterpreterIORedirect &io_redirect = **io_redirect_or_error; 161 162 if (llvm::Error e = 163 m_lua->ChangeIO(io_redirect.GetOutputFile()->GetStream(), 164 io_redirect.GetErrorFile()->GetStream())) { 165 result->AppendErrorWithFormatv("lua failed to redirect I/O: {0}\n", 166 llvm::toString(std::move(e))); 167 return false; 168 } 169 170 if (llvm::Error e = m_lua->Run(command)) { 171 result->AppendErrorWithFormatv( 172 "lua failed attempting to evaluate '{0}': {1}\n", command, 173 llvm::toString(std::move(e))); 174 return false; 175 } 176 177 io_redirect.Flush(); 178 return true; 179 } 180 181 void ScriptInterpreterLua::ExecuteInterpreterLoop() { 182 LLDB_SCOPED_TIMER(); 183 184 // At the moment, the only time the debugger does not have an input file 185 // handle is when this is called directly from lua, in which case it is 186 // both dangerous and unnecessary (not to mention confusing) to try to embed 187 // a running interpreter loop inside the already running lua interpreter 188 // loop, so we won't do it. 189 if (!m_debugger.GetInputFile().IsValid()) 190 return; 191 192 IOHandlerSP io_handler_sp(new IOHandlerLuaInterpreter(m_debugger, *this)); 193 m_debugger.RunIOHandlerAsync(io_handler_sp); 194 } 195 196 bool ScriptInterpreterLua::LoadScriptingModule( 197 const char *filename, bool init_session, lldb_private::Status &error, 198 StructuredData::ObjectSP *module_sp, FileSpec extra_search_dir) { 199 200 FileSystem::Instance().Collect(filename); 201 if (llvm::Error e = m_lua->LoadModule(filename)) { 202 error.SetErrorStringWithFormatv("lua failed to import '{0}': {1}\n", 203 filename, llvm::toString(std::move(e))); 204 return false; 205 } 206 return true; 207 } 208 209 void ScriptInterpreterLua::Initialize() { 210 static llvm::once_flag g_once_flag; 211 212 llvm::call_once(g_once_flag, []() { 213 PluginManager::RegisterPlugin(GetPluginNameStatic(), 214 GetPluginDescriptionStatic(), 215 lldb::eScriptLanguageLua, CreateInstance); 216 }); 217 } 218 219 void ScriptInterpreterLua::Terminate() {} 220 221 llvm::Error ScriptInterpreterLua::EnterSession(user_id_t debugger_id) { 222 if (m_session_is_active) 223 return llvm::Error::success(); 224 225 const char *fmt_str = 226 "lldb.debugger = lldb.SBDebugger.FindDebuggerWithID({0}); " 227 "lldb.target = lldb.debugger:GetSelectedTarget(); " 228 "lldb.process = lldb.target:GetProcess(); " 229 "lldb.thread = lldb.process:GetSelectedThread(); " 230 "lldb.frame = lldb.thread:GetSelectedFrame()"; 231 return m_lua->Run(llvm::formatv(fmt_str, debugger_id).str()); 232 } 233 234 llvm::Error ScriptInterpreterLua::LeaveSession() { 235 if (!m_session_is_active) 236 return llvm::Error::success(); 237 238 m_session_is_active = false; 239 240 llvm::StringRef str = "lldb.debugger = nil; " 241 "lldb.target = nil; " 242 "lldb.process = nil; " 243 "lldb.thread = nil; " 244 "lldb.frame = nil"; 245 return m_lua->Run(str); 246 } 247 248 bool ScriptInterpreterLua::BreakpointCallbackFunction( 249 void *baton, StoppointCallbackContext *context, user_id_t break_id, 250 user_id_t break_loc_id) { 251 assert(context); 252 253 ExecutionContext exe_ctx(context->exe_ctx_ref); 254 Target *target = exe_ctx.GetTargetPtr(); 255 if (target == nullptr) 256 return true; 257 258 StackFrameSP stop_frame_sp(exe_ctx.GetFrameSP()); 259 BreakpointSP breakpoint_sp = target->GetBreakpointByID(break_id); 260 BreakpointLocationSP bp_loc_sp(breakpoint_sp->FindLocationByID(break_loc_id)); 261 262 Debugger &debugger = target->GetDebugger(); 263 ScriptInterpreterLua *lua_interpreter = static_cast<ScriptInterpreterLua *>( 264 debugger.GetScriptInterpreter(true, eScriptLanguageLua)); 265 Lua &lua = lua_interpreter->GetLua(); 266 267 CommandDataLua *bp_option_data = static_cast<CommandDataLua *>(baton); 268 llvm::Expected<bool> BoolOrErr = lua.CallBreakpointCallback( 269 baton, stop_frame_sp, bp_loc_sp, bp_option_data->m_extra_args_sp); 270 if (llvm::Error E = BoolOrErr.takeError()) { 271 debugger.GetErrorStream() << toString(std::move(E)); 272 return true; 273 } 274 275 return *BoolOrErr; 276 } 277 278 void ScriptInterpreterLua::CollectDataForBreakpointCommandCallback( 279 std::vector<BreakpointOptions *> &bp_options_vec, 280 CommandReturnObject &result) { 281 IOHandlerSP io_handler_sp( 282 new IOHandlerLuaInterpreter(m_debugger, *this, eIOHandlerBreakpoint)); 283 io_handler_sp->SetUserData(&bp_options_vec); 284 m_debugger.RunIOHandlerAsync(io_handler_sp); 285 } 286 287 Status ScriptInterpreterLua::SetBreakpointCommandCallbackFunction( 288 BreakpointOptions *bp_options, const char *function_name, 289 StructuredData::ObjectSP extra_args_sp) { 290 const char *fmt_str = "return {0}(frame, bp_loc, ...)"; 291 std::string oneliner = llvm::formatv(fmt_str, function_name).str(); 292 return RegisterBreakpointCallback(bp_options, oneliner.c_str(), 293 extra_args_sp); 294 } 295 296 Status ScriptInterpreterLua::SetBreakpointCommandCallback( 297 BreakpointOptions *bp_options, const char *command_body_text) { 298 return RegisterBreakpointCallback(bp_options, command_body_text, {}); 299 } 300 301 Status ScriptInterpreterLua::RegisterBreakpointCallback( 302 BreakpointOptions *bp_options, const char *command_body_text, 303 StructuredData::ObjectSP extra_args_sp) { 304 Status error; 305 auto data_up = std::make_unique<CommandDataLua>(extra_args_sp); 306 error = m_lua->RegisterBreakpointCallback(data_up.get(), command_body_text); 307 if (error.Fail()) 308 return error; 309 auto baton_sp = 310 std::make_shared<BreakpointOptions::CommandBaton>(std::move(data_up)); 311 bp_options->SetCallback(ScriptInterpreterLua::BreakpointCallbackFunction, 312 baton_sp); 313 return error; 314 } 315 316 lldb::ScriptInterpreterSP 317 ScriptInterpreterLua::CreateInstance(Debugger &debugger) { 318 return std::make_shared<ScriptInterpreterLua>(debugger); 319 } 320 321 lldb_private::ConstString ScriptInterpreterLua::GetPluginNameStatic() { 322 static ConstString g_name("script-lua"); 323 return g_name; 324 } 325 326 const char *ScriptInterpreterLua::GetPluginDescriptionStatic() { 327 return "Lua script interpreter"; 328 } 329 330 lldb_private::ConstString ScriptInterpreterLua::GetPluginName() { 331 return GetPluginNameStatic(); 332 } 333 334 uint32_t ScriptInterpreterLua::GetPluginVersion() { return 1; } 335 336 Lua &ScriptInterpreterLua::GetLua() { return *m_lua; } 337