//===-- ScriptInterpreterLua.cpp ------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "ScriptInterpreterLua.h"
#include "Lua.h"
#include "lldb/Breakpoint/StoppointCallbackContext.h"
#include "lldb/Core/Debugger.h"
#include "lldb/Core/PluginManager.h"
#include "lldb/Host/StreamFile.h"
#include "lldb/Interpreter/CommandReturnObject.h"
#include "lldb/Target/ExecutionContext.h"
#include "lldb/Utility/Stream.h"
#include "lldb/Utility/StringList.h"
#include "lldb/Utility/Timer.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/Support/FormatAdapters.h"
#include <memory>
#include <vector>
using namespace lldb;
using namespace lldb_private;
LLDB_PLUGIN_DEFINE(ScriptInterpreterLua)
enum ActiveIOHandler {
eIOHandlerNone,
eIOHandlerBreakpoint,
eIOHandlerWatchpoint
};
class IOHandlerLuaInterpreter : public IOHandlerDelegate,
public IOHandlerEditline {
public:
IOHandlerLuaInterpreter(Debugger &debugger,
ScriptInterpreterLua &script_interpreter,
ActiveIOHandler active_io_handler = eIOHandlerNone)
: IOHandlerEditline(debugger, IOHandler::Type::LuaInterpreter, "lua",
llvm::StringRef(">>> "), llvm::StringRef("..> "),
true, debugger.GetUseColor(), 0, *this),
m_script_interpreter(script_interpreter),
m_active_io_handler(active_io_handler) {
llvm::cantFail(m_script_interpreter.GetLua().ChangeIO(
debugger.GetOutputFile().GetStream(),
debugger.GetErrorFile().GetStream()));
llvm::cantFail(m_script_interpreter.EnterSession(debugger.GetID()));
}
~IOHandlerLuaInterpreter() override {
llvm::cantFail(m_script_interpreter.LeaveSession());
}
void IOHandlerActivated(IOHandler &io_handler, bool interactive) override {
const char *instructions = nullptr;
switch (m_active_io_handler) {
case eIOHandlerNone:
break;
case eIOHandlerWatchpoint:
instructions = "Enter your Lua command(s). Type 'quit' to end.\n"
"The commands are compiled as the body of the following "
"Lua function\n"
"function (frame, wp) end\n";
SetPrompt(llvm::StringRef("..> "));
break;
case eIOHandlerBreakpoint:
instructions = "Enter your Lua command(s). Type 'quit' to end.\n"
"The commands are compiled as the body of the following "
"Lua function\n"
"function (frame, bp_loc, ...) end\n";
SetPrompt(llvm::StringRef("..> "));
break;
}
if (instructions == nullptr)
return;
if (interactive)
*io_handler.GetOutputStreamFileSP() << instructions;
}
bool IOHandlerIsInputComplete(IOHandler &io_handler,
StringList &lines) override {
size_t last = lines.GetSize() - 1;
if (IsQuitCommand(lines.GetStringAtIndex(last))) {
if (m_active_io_handler == eIOHandlerBreakpoint ||
m_active_io_handler == eIOHandlerWatchpoint)
lines.DeleteStringAtIndex(last);
return true;
}
StreamString str;
lines.Join("\n", str);
if (llvm::Error E =
m_script_interpreter.GetLua().CheckSyntax(str.GetString())) {
std::string error_str = toString(std::move(E));
// Lua always errors out to incomplete code with '<eof>'
return error_str.find("<eof>") == std::string::npos;
}
// The breakpoint and watchpoint handler only exits with a explicit 'quit'
return m_active_io_handler != eIOHandlerBreakpoint &&
m_active_io_handler != eIOHandlerWatchpoint;
}
void IOHandlerInputComplete(IOHandler &io_handler,
std::string &data) override {
switch (m_active_io_handler) {
case eIOHandlerBreakpoint: {
auto *bp_options_vec =
static_cast<std::vector<std::reference_wrapper<BreakpointOptions>> *>(
io_handler.GetUserData());
for (BreakpointOptions &bp_options : *bp_options_vec) {
Status error = m_script_interpreter.SetBreakpointCommandCallback(
bp_options, data.c_str(), /*is_callback=*/false);
if (error.Fail())
*io_handler.GetErrorStreamFileSP() << error.AsCString() << '\n';
}
io_handler.SetIsDone(true);
} break;
case eIOHandlerWatchpoint: {
auto *wp_options =
static_cast<WatchpointOptions *>(io_handler.GetUserData());
m_script_interpreter.SetWatchpointCommandCallback(wp_options,
data.c_str(),
/*is_callback=*/false);
io_handler.SetIsDone(true);
} break;
case eIOHandlerNone:
if (IsQuitCommand(data)) {
io_handler.SetIsDone(true);
return;
}
if (llvm::Error error = m_script_interpreter.GetLua().Run(data))
*io_handler.GetErrorStreamFileSP() << toString(std::move(error));
break;
}
}
private:
ScriptInterpreterLua &m_script_interpreter;
ActiveIOHandler m_active_io_handler;
bool IsQuitCommand(llvm::StringRef cmd) { return cmd.rtrim() == "quit"; }
};
ScriptInterpreterLua::ScriptInterpreterLua(Debugger &debugger)
: ScriptInterpreter(debugger, eScriptLanguageLua),
m_lua(std::make_unique<Lua>()) {}
ScriptInterpreterLua::~ScriptInterpreterLua() = default;
StructuredData::DictionarySP ScriptInterpreterLua::GetInterpreterInfo() {
auto info = std::make_shared<StructuredData::Dictionary>();
info->AddStringItem("language", "lua");
return info;
}
bool ScriptInterpreterLua::ExecuteOneLine(llvm::StringRef command,
CommandReturnObject *result,
const ExecuteScriptOptions &options) {
if (command.empty()) {
if (result)
result->AppendError("empty command passed to lua\n");
return false;
}
llvm::Expected<std::unique_ptr<ScriptInterpreterIORedirect>>
io_redirect_or_error = ScriptInterpreterIORedirect::Create(
options.GetEnableIO(), m_debugger, result);
if (!io_redirect_or_error) {
if (result)
result->AppendErrorWithFormatv(
"failed to redirect I/O: {0}\n",
llvm::fmt_consume(io_redirect_or_error.takeError()));
else
llvm::consumeError(io_redirect_or_error.takeError());
return false;
}
ScriptInterpreterIORedirect &io_redirect = **io_redirect_or_error;
if (llvm::Error e =
m_lua->ChangeIO(io_redirect.GetOutputFile()->GetStream(),
io_redirect.GetErrorFile()->GetStream())) {
result->AppendErrorWithFormatv("lua failed to redirect I/O: {0}\n",
llvm::toString(std::move(e)));
return false;
}
if (llvm::Error e = m_lua->Run(command)) {
result->AppendErrorWithFormatv(
"lua failed attempting to evaluate '{0}': {1}\n", command,
llvm::toString(std::move(e)));
return false;
}
io_redirect.Flush();
return true;
}
void ScriptInterpreterLua::ExecuteInterpreterLoop() {
LLDB_SCOPED_TIMER();
// At the moment, the only time the debugger does not have an input file
// handle is when this is called directly from lua, in which case it is
// both dangerous and unnecessary (not to mention confusing) to try to embed
// a running interpreter loop inside the already running lua interpreter
// loop, so we won't do it.
if (!m_debugger.GetInputFile().IsValid())
return;
IOHandlerSP io_handler_sp(new IOHandlerLuaInterpreter(m_debugger, *this));
m_debugger.RunIOHandlerAsync(io_handler_sp);
}
bool ScriptInterpreterLua::LoadScriptingModule(
const char *filename, const LoadScriptOptions &options,
lldb_private::Status &error, StructuredData::ObjectSP *module_sp,
FileSpec extra_search_dir) {
if (llvm::Error e = m_lua->LoadModule(filename)) {
error = Status::FromErrorStringWithFormatv(
"lua failed to import '{0}': {1}\n", filename,
llvm::toString(std::move(e)));
return false;
}
return true;
}
void ScriptInterpreterLua::Initialize() {
static llvm::once_flag g_once_flag;
llvm::call_once(g_once_flag, []() {
PluginManager::RegisterPlugin(GetPluginNameStatic(),
GetPluginDescriptionStatic(),
lldb::eScriptLanguageLua, CreateInstance);
});
}
void ScriptInterpreterLua::Terminate() {}
llvm::Error ScriptInterpreterLua::EnterSession(user_id_t debugger_id) {
if (m_session_is_active)
return llvm::Error::success();
const char *fmt_str =
"lldb.debugger = lldb.SBDebugger.FindDebuggerWithID({0}); "
"lldb.target = lldb.debugger:GetSelectedTarget(); "
"lldb.process = lldb.target:GetProcess(); "
"lldb.thread = lldb.process:GetSelectedThread(); "
"lldb.frame = lldb.thread:GetSelectedFrame()";
return m_lua->Run(llvm::formatv(fmt_str, debugger_id).str());
}
llvm::Error ScriptInterpreterLua::LeaveSession() {
if (!m_session_is_active)
return llvm::Error::success();
m_session_is_active = false;
llvm::StringRef str = "lldb.debugger = nil; "
"lldb.target = nil; "
"lldb.process = nil; "
"lldb.thread = nil; "
"lldb.frame = nil";
return m_lua->Run(str);
}
bool ScriptInterpreterLua::BreakpointCallbackFunction(
void *baton, StoppointCallbackContext *context, user_id_t break_id,
user_id_t break_loc_id) {
assert(context);
ExecutionContext exe_ctx(context->exe_ctx_ref);
Target *target = exe_ctx.GetTargetPtr();
if (target == nullptr)
return true;
StackFrameSP stop_frame_sp(exe_ctx.GetFrameSP());
BreakpointSP breakpoint_sp = target->GetBreakpointByID(break_id);
BreakpointLocationSP bp_loc_sp(breakpoint_sp->FindLocationByID(break_loc_id));
Debugger &debugger = target->GetDebugger();
ScriptInterpreterLua *lua_interpreter = static_cast<ScriptInterpreterLua *>(
debugger.GetScriptInterpreter(true, eScriptLanguageLua));
Lua &lua = lua_interpreter->GetLua();
CommandDataLua *bp_option_data = static_cast<CommandDataLua *>(baton);
llvm::Expected<bool> BoolOrErr = lua.CallBreakpointCallback(
baton, stop_frame_sp, bp_loc_sp, bp_option_data->m_extra_args_sp);
if (llvm::Error E = BoolOrErr.takeError()) {
debugger.GetErrorStream() << toString(std::move(E));
return true;
}
return *BoolOrErr;
}
bool ScriptInterpreterLua::WatchpointCallbackFunction(
void *baton, StoppointCallbackContext *context, user_id_t watch_id) {
assert(context);
ExecutionContext exe_ctx(context->exe_ctx_ref);
Target *target = exe_ctx.GetTargetPtr();
if (target == nullptr)
return true;
StackFrameSP stop_frame_sp(exe_ctx.GetFrameSP());
WatchpointSP wp_sp = target->GetWatchpointList().FindByID(watch_id);
Debugger &debugger = target->GetDebugger();
ScriptInterpreterLua *lua_interpreter = static_cast<ScriptInterpreterLua *>(
debugger.GetScriptInterpreter(true, eScriptLanguageLua));
Lua &lua = lua_interpreter->GetLua();
llvm::Expected<bool> BoolOrErr =
lua.CallWatchpointCallback(baton, stop_frame_sp, wp_sp);
if (llvm::Error E = BoolOrErr.takeError()) {
debugger.GetErrorStream() << toString(std::move(E));
return true;
}
return *BoolOrErr;
}
void ScriptInterpreterLua::CollectDataForBreakpointCommandCallback(
std::vector<std::reference_wrapper<BreakpointOptions>> &bp_options_vec,
CommandReturnObject &result) {
IOHandlerSP io_handler_sp(
new IOHandlerLuaInterpreter(m_debugger, *this, eIOHandlerBreakpoint));
io_handler_sp->SetUserData(&bp_options_vec);
m_debugger.RunIOHandlerAsync(io_handler_sp);
}
void ScriptInterpreterLua::CollectDataForWatchpointCommandCallback(
WatchpointOptions *wp_options, CommandReturnObject &result) {
IOHandlerSP io_handler_sp(
new IOHandlerLuaInterpreter(m_debugger, *this, eIOHandlerWatchpoint));
io_handler_sp->SetUserData(wp_options);
m_debugger.RunIOHandlerAsync(io_handler_sp);
}
Status ScriptInterpreterLua::SetBreakpointCommandCallbackFunction(
BreakpointOptions &bp_options, const char *function_name,
StructuredData::ObjectSP extra_args_sp) {
const char *fmt_str = "return {0}(frame, bp_loc, ...)";
std::string oneliner = llvm::formatv(fmt_str, function_name).str();
return RegisterBreakpointCallback(bp_options, oneliner.c_str(),
extra_args_sp);
}
Status ScriptInterpreterLua::SetBreakpointCommandCallback(
BreakpointOptions &bp_options, const char *command_body_text,
bool is_callback) {
return RegisterBreakpointCallback(bp_options, command_body_text, {});
}
Status ScriptInterpreterLua::RegisterBreakpointCallback(
BreakpointOptions &bp_options, const char *command_body_text,
StructuredData::ObjectSP extra_args_sp) {
auto data_up = std::make_unique<CommandDataLua>(extra_args_sp);
llvm::Error err =
m_lua->RegisterBreakpointCallback(data_up.get(), command_body_text);
if (err)
return Status::FromError(std::move(err));
auto baton_sp =
std::make_shared<BreakpointOptions::CommandBaton>(std::move(data_up));
bp_options.SetCallback(ScriptInterpreterLua::BreakpointCallbackFunction,
baton_sp);
return {};
}
void ScriptInterpreterLua::SetWatchpointCommandCallback(
WatchpointOptions *wp_options, const char *command_body_text,
bool is_callback) {
RegisterWatchpointCallback(wp_options, command_body_text, {});
}
Status ScriptInterpreterLua::RegisterWatchpointCallback(
WatchpointOptions *wp_options, const char *command_body_text,
StructuredData::ObjectSP extra_args_sp) {
auto data_up = std::make_unique<WatchpointOptions::CommandData>();
llvm::Error err =
m_lua->RegisterWatchpointCallback(data_up.get(), command_body_text);
if (err)
return Status::FromError(std::move(err));
auto baton_sp =
std::make_shared<WatchpointOptions::CommandBaton>(std::move(data_up));
wp_options->SetCallback(ScriptInterpreterLua::WatchpointCallbackFunction,
baton_sp);
return {};
}
lldb::ScriptInterpreterSP
ScriptInterpreterLua::CreateInstance(Debugger &debugger) {
return std::make_shared<ScriptInterpreterLua>(debugger);
}
llvm::StringRef ScriptInterpreterLua::GetPluginDescriptionStatic() {
return "Lua script interpreter";
}
Lua &ScriptInterpreterLua::GetLua() { return *m_lua; }
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