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/Support/FormatAdapters.h"
21 #include <memory>
22
23 using namespace lldb;
24 using namespace lldb_private;
25
26 LLDB_PLUGIN_DEFINE(ScriptInterpreterLua)
27
28 class IOHandlerLuaInterpreter : public IOHandlerDelegate,
29 public IOHandlerEditline {
30 public:
IOHandlerLuaInterpreter(Debugger & debugger,ScriptInterpreterLua & script_interpreter)31 IOHandlerLuaInterpreter(Debugger &debugger,
32 ScriptInterpreterLua &script_interpreter)
33 : IOHandlerEditline(debugger, IOHandler::Type::LuaInterpreter, "lua",
34 ">>> ", "..> ", true, debugger.GetUseColor(), 0,
35 *this, nullptr),
36 m_script_interpreter(script_interpreter) {
37 llvm::cantFail(m_script_interpreter.GetLua().ChangeIO(
38 debugger.GetOutputFile().GetStream(),
39 debugger.GetErrorFile().GetStream()));
40 llvm::cantFail(m_script_interpreter.EnterSession(debugger.GetID()));
41 }
42
~IOHandlerLuaInterpreter()43 ~IOHandlerLuaInterpreter() override {
44 llvm::cantFail(m_script_interpreter.LeaveSession());
45 }
46
IOHandlerInputComplete(IOHandler & io_handler,std::string & data)47 void IOHandlerInputComplete(IOHandler &io_handler,
48 std::string &data) override {
49 if (llvm::StringRef(data).rtrim() == "quit") {
50 io_handler.SetIsDone(true);
51 return;
52 }
53
54 if (llvm::Error error = m_script_interpreter.GetLua().Run(data)) {
55 *GetOutputStreamFileSP() << llvm::toString(std::move(error));
56 }
57 }
58
59 private:
60 ScriptInterpreterLua &m_script_interpreter;
61 };
62
ScriptInterpreterLua(Debugger & debugger)63 ScriptInterpreterLua::ScriptInterpreterLua(Debugger &debugger)
64 : ScriptInterpreter(debugger, eScriptLanguageLua),
65 m_lua(std::make_unique<Lua>()) {}
66
~ScriptInterpreterLua()67 ScriptInterpreterLua::~ScriptInterpreterLua() {}
68
ExecuteOneLine(llvm::StringRef command,CommandReturnObject * result,const ExecuteScriptOptions & options)69 bool ScriptInterpreterLua::ExecuteOneLine(llvm::StringRef command,
70 CommandReturnObject *result,
71 const ExecuteScriptOptions &options) {
72 if (command.empty()) {
73 if (result)
74 result->AppendError("empty command passed to lua\n");
75 return false;
76 }
77
78 llvm::Expected<std::unique_ptr<ScriptInterpreterIORedirect>>
79 io_redirect_or_error = ScriptInterpreterIORedirect::Create(
80 options.GetEnableIO(), m_debugger, result);
81 if (!io_redirect_or_error) {
82 if (result)
83 result->AppendErrorWithFormatv(
84 "failed to redirect I/O: {0}\n",
85 llvm::fmt_consume(io_redirect_or_error.takeError()));
86 else
87 llvm::consumeError(io_redirect_or_error.takeError());
88 return false;
89 }
90
91 ScriptInterpreterIORedirect &io_redirect = **io_redirect_or_error;
92
93 if (llvm::Error e =
94 m_lua->ChangeIO(io_redirect.GetOutputFile()->GetStream(),
95 io_redirect.GetErrorFile()->GetStream())) {
96 result->AppendErrorWithFormatv("lua failed to redirect I/O: {0}\n",
97 llvm::toString(std::move(e)));
98 return false;
99 }
100
101 if (llvm::Error e = m_lua->Run(command)) {
102 result->AppendErrorWithFormatv(
103 "lua failed attempting to evaluate '{0}': {1}\n", command,
104 llvm::toString(std::move(e)));
105 return false;
106 }
107
108 io_redirect.Flush();
109 return true;
110 }
111
ExecuteInterpreterLoop()112 void ScriptInterpreterLua::ExecuteInterpreterLoop() {
113 static Timer::Category func_cat(LLVM_PRETTY_FUNCTION);
114 Timer scoped_timer(func_cat, LLVM_PRETTY_FUNCTION);
115
116 // At the moment, the only time the debugger does not have an input file
117 // handle is when this is called directly from lua, in which case it is
118 // both dangerous and unnecessary (not to mention confusing) to try to embed
119 // a running interpreter loop inside the already running lua interpreter
120 // loop, so we won't do it.
121 if (!m_debugger.GetInputFile().IsValid())
122 return;
123
124 IOHandlerSP io_handler_sp(new IOHandlerLuaInterpreter(m_debugger, *this));
125 m_debugger.RunIOHandlerAsync(io_handler_sp);
126 }
127
LoadScriptingModule(const char * filename,bool init_session,lldb_private::Status & error,StructuredData::ObjectSP * module_sp,FileSpec extra_search_dir)128 bool ScriptInterpreterLua::LoadScriptingModule(
129 const char *filename, bool init_session, lldb_private::Status &error,
130 StructuredData::ObjectSP *module_sp, FileSpec extra_search_dir) {
131
132 FileSystem::Instance().Collect(filename);
133 if (llvm::Error e = m_lua->LoadModule(filename)) {
134 error.SetErrorStringWithFormatv("lua failed to import '{0}': {1}\n",
135 filename, llvm::toString(std::move(e)));
136 return false;
137 }
138 return true;
139 }
140
Initialize()141 void ScriptInterpreterLua::Initialize() {
142 static llvm::once_flag g_once_flag;
143
144 llvm::call_once(g_once_flag, []() {
145 PluginManager::RegisterPlugin(GetPluginNameStatic(),
146 GetPluginDescriptionStatic(),
147 lldb::eScriptLanguageLua, CreateInstance);
148 });
149 }
150
Terminate()151 void ScriptInterpreterLua::Terminate() {}
152
EnterSession(user_id_t debugger_id)153 llvm::Error ScriptInterpreterLua::EnterSession(user_id_t debugger_id) {
154 if (m_session_is_active)
155 return llvm::Error::success();
156
157 const char *fmt_str =
158 "lldb.debugger = lldb.SBDebugger.FindDebuggerWithID({0}); "
159 "lldb.target = lldb.debugger:GetSelectedTarget(); "
160 "lldb.process = lldb.target:GetProcess(); "
161 "lldb.thread = lldb.process:GetSelectedThread(); "
162 "lldb.frame = lldb.thread:GetSelectedFrame()";
163 return m_lua->Run(llvm::formatv(fmt_str, debugger_id).str());
164 }
165
LeaveSession()166 llvm::Error ScriptInterpreterLua::LeaveSession() {
167 if (!m_session_is_active)
168 return llvm::Error::success();
169
170 m_session_is_active = false;
171
172 llvm::StringRef str = "lldb.debugger = nil; "
173 "lldb.target = nil; "
174 "lldb.process = nil; "
175 "lldb.thread = nil; "
176 "lldb.frame = nil";
177 return m_lua->Run(str);
178 }
179
BreakpointCallbackFunction(void * baton,StoppointCallbackContext * context,user_id_t break_id,user_id_t break_loc_id)180 bool ScriptInterpreterLua::BreakpointCallbackFunction(
181 void *baton, StoppointCallbackContext *context, user_id_t break_id,
182 user_id_t break_loc_id) {
183 assert(context);
184
185 ExecutionContext exe_ctx(context->exe_ctx_ref);
186 Target *target = exe_ctx.GetTargetPtr();
187 if (target == nullptr)
188 return true;
189
190 StackFrameSP stop_frame_sp(exe_ctx.GetFrameSP());
191 BreakpointSP breakpoint_sp = target->GetBreakpointByID(break_id);
192 BreakpointLocationSP bp_loc_sp(breakpoint_sp->FindLocationByID(break_loc_id));
193
194 Debugger &debugger = target->GetDebugger();
195 ScriptInterpreterLua *lua_interpreter = static_cast<ScriptInterpreterLua *>(
196 debugger.GetScriptInterpreter(true, eScriptLanguageLua));
197 Lua &lua = lua_interpreter->GetLua();
198
199 llvm::Expected<bool> BoolOrErr =
200 lua.CallBreakpointCallback(baton, stop_frame_sp, bp_loc_sp);
201 if (llvm::Error E = BoolOrErr.takeError()) {
202 debugger.GetErrorStream() << toString(std::move(E));
203 return true;
204 }
205
206 return *BoolOrErr;
207 }
208
SetBreakpointCommandCallback(BreakpointOptions * bp_options,const char * command_body_text)209 Status ScriptInterpreterLua::SetBreakpointCommandCallback(
210 BreakpointOptions *bp_options, const char *command_body_text) {
211 Status error;
212 auto data_up = std::make_unique<CommandDataLua>();
213 error = m_lua->RegisterBreakpointCallback(data_up.get(), command_body_text);
214 if (error.Fail())
215 return error;
216 auto baton_sp =
217 std::make_shared<BreakpointOptions::CommandBaton>(std::move(data_up));
218 bp_options->SetCallback(ScriptInterpreterLua::BreakpointCallbackFunction,
219 baton_sp);
220 return error;
221 }
222
223 lldb::ScriptInterpreterSP
CreateInstance(Debugger & debugger)224 ScriptInterpreterLua::CreateInstance(Debugger &debugger) {
225 return std::make_shared<ScriptInterpreterLua>(debugger);
226 }
227
GetPluginNameStatic()228 lldb_private::ConstString ScriptInterpreterLua::GetPluginNameStatic() {
229 static ConstString g_name("script-lua");
230 return g_name;
231 }
232
GetPluginDescriptionStatic()233 const char *ScriptInterpreterLua::GetPluginDescriptionStatic() {
234 return "Lua script interpreter";
235 }
236
GetPluginName()237 lldb_private::ConstString ScriptInterpreterLua::GetPluginName() {
238 return GetPluginNameStatic();
239 }
240
GetPluginVersion()241 uint32_t ScriptInterpreterLua::GetPluginVersion() { return 1; }
242
GetLua()243 Lua &ScriptInterpreterLua::GetLua() { return *m_lua; }
244