//===-- Lua.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 "Lua.h"
#include "SWIGLuaBridge.h"
#include "lldb/Host/FileSystem.h"
#include "lldb/Utility/FileSpec.h"
#include "llvm/Support/Error.h"
#include "llvm/Support/FormatVariadic.h"
using namespace lldb_private;
using namespace lldb;
static int lldb_print(lua_State *L) {
int n = lua_gettop(L);
lua_getglobal(L, "io");
lua_getfield(L, -1, "stdout");
lua_getfield(L, -1, "write");
for (int i = 1; i <= n; i++) {
lua_pushvalue(L, -1); // write()
lua_pushvalue(L, -3); // io.stdout
luaL_tolstring(L, i, nullptr);
lua_pushstring(L, i != n ? "\t" : "\n");
lua_call(L, 3, 0);
}
return 0;
}
Lua::Lua() : m_lua_state(luaL_newstate()) {
assert(m_lua_state);
luaL_openlibs(m_lua_state);
luaopen_lldb(m_lua_state);
lua_pushcfunction(m_lua_state, lldb_print);
lua_setglobal(m_lua_state, "print");
}
Lua::~Lua() {
assert(m_lua_state);
lua_close(m_lua_state);
}
llvm::Error Lua::Run(llvm::StringRef buffer) {
int error =
luaL_loadbuffer(m_lua_state, buffer.data(), buffer.size(), "buffer") ||
lua_pcall(m_lua_state, 0, 0, 0);
if (error == LUA_OK)
return llvm::Error::success();
llvm::Error e = llvm::make_error<llvm::StringError>(
llvm::formatv("{0}\n", lua_tostring(m_lua_state, -1)),
llvm::inconvertibleErrorCode());
// Pop error message from the stack.
lua_pop(m_lua_state, 1);
return e;
}
llvm::Error Lua::RegisterBreakpointCallback(void *baton, const char *body) {
lua_pushlightuserdata(m_lua_state, baton);
const char *fmt_str = "return function(frame, bp_loc, ...) {0} end";
std::string func_str = llvm::formatv(fmt_str, body).str();
if (luaL_dostring(m_lua_state, func_str.c_str()) != LUA_OK) {
llvm::Error e = llvm::make_error<llvm::StringError>(
llvm::formatv("{0}", lua_tostring(m_lua_state, -1)),
llvm::inconvertibleErrorCode());
// Pop error message from the stack.
lua_pop(m_lua_state, 2);
return e;
}
lua_settable(m_lua_state, LUA_REGISTRYINDEX);
return llvm::Error::success();
}
llvm::Expected<bool>
Lua::CallBreakpointCallback(void *baton, lldb::StackFrameSP stop_frame_sp,
lldb::BreakpointLocationSP bp_loc_sp,
StructuredData::ObjectSP extra_args_sp) {
lua_pushlightuserdata(m_lua_state, baton);
lua_gettable(m_lua_state, LUA_REGISTRYINDEX);
StructuredDataImpl extra_args_impl(std::move(extra_args_sp));
return lua::SWIGBridge::LLDBSwigLuaBreakpointCallbackFunction(
m_lua_state, stop_frame_sp, bp_loc_sp, extra_args_impl);
}
llvm::Error Lua::RegisterWatchpointCallback(void *baton, const char *body) {
lua_pushlightuserdata(m_lua_state, baton);
const char *fmt_str = "return function(frame, wp, ...) {0} end";
std::string func_str = llvm::formatv(fmt_str, body).str();
if (luaL_dostring(m_lua_state, func_str.c_str()) != LUA_OK) {
llvm::Error e = llvm::make_error<llvm::StringError>(
llvm::formatv("{0}", lua_tostring(m_lua_state, -1)),
llvm::inconvertibleErrorCode());
// Pop error message from the stack.
lua_pop(m_lua_state, 2);
return e;
}
lua_settable(m_lua_state, LUA_REGISTRYINDEX);
return llvm::Error::success();
}
llvm::Expected<bool>
Lua::CallWatchpointCallback(void *baton, lldb::StackFrameSP stop_frame_sp,
lldb::WatchpointSP wp_sp) {
lua_pushlightuserdata(m_lua_state, baton);
lua_gettable(m_lua_state, LUA_REGISTRYINDEX);
return lua::SWIGBridge::LLDBSwigLuaWatchpointCallbackFunction(
m_lua_state, stop_frame_sp, wp_sp);
}
llvm::Error Lua::CheckSyntax(llvm::StringRef buffer) {
int error =
luaL_loadbuffer(m_lua_state, buffer.data(), buffer.size(), "buffer");
if (error == LUA_OK) {
// Pop buffer
lua_pop(m_lua_state, 1);
return llvm::Error::success();
}
llvm::Error e = llvm::make_error<llvm::StringError>(
llvm::formatv("{0}\n", lua_tostring(m_lua_state, -1)),
llvm::inconvertibleErrorCode());
// Pop error message from the stack.
lua_pop(m_lua_state, 1);
return e;
}
llvm::Error Lua::LoadModule(llvm::StringRef filename) {
const FileSpec file(filename);
if (!FileSystem::Instance().Exists(file)) {
return llvm::make_error<llvm::StringError>("invalid path",
llvm::inconvertibleErrorCode());
}
if (file.GetFileNameExtension() != ".lua") {
return llvm::make_error<llvm::StringError>("invalid extension",
llvm::inconvertibleErrorCode());
}
int error = luaL_loadfile(m_lua_state, filename.data()) ||
lua_pcall(m_lua_state, 0, 1, 0);
if (error != LUA_OK) {
llvm::Error e = llvm::make_error<llvm::StringError>(
llvm::formatv("{0}\n", lua_tostring(m_lua_state, -1)),
llvm::inconvertibleErrorCode());
// Pop error message from the stack.
lua_pop(m_lua_state, 1);
return e;
}
ConstString module_name = file.GetFileNameStrippingExtension();
lua_setglobal(m_lua_state, module_name.GetCString());
return llvm::Error::success();
}
llvm::Error Lua::ChangeIO(FILE *out, FILE *err) {
assert(out != nullptr);
assert(err != nullptr);
lua_getglobal(m_lua_state, "io");
lua_getfield(m_lua_state, -1, "stdout");
if (luaL_Stream *s = static_cast<luaL_Stream *>(
luaL_testudata(m_lua_state, -1, LUA_FILEHANDLE))) {
s->f = out;
lua_pop(m_lua_state, 1);
} else {
lua_pop(m_lua_state, 2);
return llvm::make_error<llvm::StringError>("could not get stdout",
llvm::inconvertibleErrorCode());
}
lua_getfield(m_lua_state, -1, "stderr");
if (luaL_Stream *s = static_cast<luaL_Stream *>(
luaL_testudata(m_lua_state, -1, LUA_FILEHANDLE))) {
s->f = out;
lua_pop(m_lua_state, 1);
} else {
lua_pop(m_lua_state, 2);
return llvm::make_error<llvm::StringError>("could not get stderr",
llvm::inconvertibleErrorCode());
}
lua_pop(m_lua_state, 1);
return llvm::Error::success();
}