1 //===-- Lua.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 "Lua.h" 10 #include "lldb/Host/FileSystem.h" 11 #include "lldb/Utility/FileSpec.h" 12 #include "llvm/Support/Error.h" 13 #include "llvm/Support/FormatVariadic.h" 14 15 using namespace lldb_private; 16 using namespace lldb; 17 18 #pragma clang diagnostic push 19 #pragma clang diagnostic ignored "-Wreturn-type-c-linkage" 20 21 // Disable warning C4190: 'LLDBSwigPythonBreakpointCallbackFunction' has 22 // C-linkage specified, but returns UDT 'llvm::Expected<bool>' which is 23 // incompatible with C 24 #if _MSC_VER 25 #pragma warning (push) 26 #pragma warning (disable : 4190) 27 #endif 28 29 extern "C" llvm::Expected<bool> LLDBSwigLuaBreakpointCallbackFunction( 30 lua_State *L, lldb::StackFrameSP stop_frame_sp, 31 lldb::BreakpointLocationSP bp_loc_sp, StructuredDataImpl *extra_args_impl); 32 33 #if _MSC_VER 34 #pragma warning (pop) 35 #endif 36 37 #pragma clang diagnostic pop 38 39 static int lldb_print(lua_State *L) { 40 int n = lua_gettop(L); 41 lua_getglobal(L, "io"); 42 lua_getfield(L, -1, "stdout"); 43 lua_getfield(L, -1, "write"); 44 for (int i = 1; i <= n; i++) { 45 lua_pushvalue(L, -1); // write() 46 lua_pushvalue(L, -3); // io.stdout 47 luaL_tolstring(L, i, nullptr); 48 lua_pushstring(L, i != n ? "\t" : "\n"); 49 lua_call(L, 3, 0); 50 } 51 return 0; 52 } 53 54 Lua::Lua() : m_lua_state(luaL_newstate()) { 55 assert(m_lua_state); 56 luaL_openlibs(m_lua_state); 57 luaopen_lldb(m_lua_state); 58 lua_pushcfunction(m_lua_state, lldb_print); 59 lua_setglobal(m_lua_state, "print"); 60 } 61 62 Lua::~Lua() { 63 assert(m_lua_state); 64 lua_close(m_lua_state); 65 } 66 67 llvm::Error Lua::Run(llvm::StringRef buffer) { 68 int error = 69 luaL_loadbuffer(m_lua_state, buffer.data(), buffer.size(), "buffer") || 70 lua_pcall(m_lua_state, 0, 0, 0); 71 if (error == LUA_OK) 72 return llvm::Error::success(); 73 74 llvm::Error e = llvm::make_error<llvm::StringError>( 75 llvm::formatv("{0}\n", lua_tostring(m_lua_state, -1)), 76 llvm::inconvertibleErrorCode()); 77 // Pop error message from the stack. 78 lua_pop(m_lua_state, 1); 79 return e; 80 } 81 82 llvm::Error Lua::RegisterBreakpointCallback(void *baton, const char *body) { 83 lua_pushlightuserdata(m_lua_state, baton); 84 const char *fmt_str = "return function(frame, bp_loc, ...) {0} end"; 85 std::string func_str = llvm::formatv(fmt_str, body).str(); 86 if (luaL_dostring(m_lua_state, func_str.c_str()) != LUA_OK) { 87 llvm::Error e = llvm::make_error<llvm::StringError>( 88 llvm::formatv("{0}", lua_tostring(m_lua_state, -1)), 89 llvm::inconvertibleErrorCode()); 90 // Pop error message from the stack. 91 lua_pop(m_lua_state, 2); 92 return e; 93 } 94 lua_settable(m_lua_state, LUA_REGISTRYINDEX); 95 return llvm::Error::success(); 96 } 97 98 llvm::Expected<bool> 99 Lua::CallBreakpointCallback(void *baton, lldb::StackFrameSP stop_frame_sp, 100 lldb::BreakpointLocationSP bp_loc_sp, 101 StructuredData::ObjectSP extra_args_sp) { 102 103 lua_pushlightuserdata(m_lua_state, baton); 104 lua_gettable(m_lua_state, LUA_REGISTRYINDEX); 105 auto *extra_args_impl = [&]() -> StructuredDataImpl * { 106 if (extra_args_sp == nullptr) 107 return nullptr; 108 auto *extra_args_impl = new StructuredDataImpl(); 109 extra_args_impl->SetObjectSP(extra_args_sp); 110 return extra_args_impl; 111 }(); 112 return LLDBSwigLuaBreakpointCallbackFunction(m_lua_state, stop_frame_sp, 113 bp_loc_sp, extra_args_impl); 114 } 115 116 llvm::Error Lua::CheckSyntax(llvm::StringRef buffer) { 117 int error = 118 luaL_loadbuffer(m_lua_state, buffer.data(), buffer.size(), "buffer"); 119 if (error == LUA_OK) { 120 // Pop buffer 121 lua_pop(m_lua_state, 1); 122 return llvm::Error::success(); 123 } 124 125 llvm::Error e = llvm::make_error<llvm::StringError>( 126 llvm::formatv("{0}\n", lua_tostring(m_lua_state, -1)), 127 llvm::inconvertibleErrorCode()); 128 // Pop error message from the stack. 129 lua_pop(m_lua_state, 1); 130 return e; 131 } 132 133 llvm::Error Lua::LoadModule(llvm::StringRef filename) { 134 FileSpec file(filename); 135 if (!FileSystem::Instance().Exists(file)) { 136 return llvm::make_error<llvm::StringError>("invalid path", 137 llvm::inconvertibleErrorCode()); 138 } 139 140 ConstString module_extension = file.GetFileNameExtension(); 141 if (module_extension != ".lua") { 142 return llvm::make_error<llvm::StringError>("invalid extension", 143 llvm::inconvertibleErrorCode()); 144 } 145 146 int error = luaL_loadfile(m_lua_state, filename.data()) || 147 lua_pcall(m_lua_state, 0, 1, 0); 148 if (error != LUA_OK) { 149 llvm::Error e = llvm::make_error<llvm::StringError>( 150 llvm::formatv("{0}\n", lua_tostring(m_lua_state, -1)), 151 llvm::inconvertibleErrorCode()); 152 // Pop error message from the stack. 153 lua_pop(m_lua_state, 1); 154 return e; 155 } 156 157 ConstString module_name = file.GetFileNameStrippingExtension(); 158 lua_setglobal(m_lua_state, module_name.GetCString()); 159 return llvm::Error::success(); 160 } 161 162 llvm::Error Lua::ChangeIO(FILE *out, FILE *err) { 163 assert(out != nullptr); 164 assert(err != nullptr); 165 166 lua_getglobal(m_lua_state, "io"); 167 168 lua_getfield(m_lua_state, -1, "stdout"); 169 if (luaL_Stream *s = static_cast<luaL_Stream *>( 170 luaL_testudata(m_lua_state, -1, LUA_FILEHANDLE))) { 171 s->f = out; 172 lua_pop(m_lua_state, 1); 173 } else { 174 lua_pop(m_lua_state, 2); 175 return llvm::make_error<llvm::StringError>("could not get stdout", 176 llvm::inconvertibleErrorCode()); 177 } 178 179 lua_getfield(m_lua_state, -1, "stderr"); 180 if (luaL_Stream *s = static_cast<luaL_Stream *>( 181 luaL_testudata(m_lua_state, -1, LUA_FILEHANDLE))) { 182 s->f = out; 183 lua_pop(m_lua_state, 1); 184 } else { 185 lua_pop(m_lua_state, 2); 186 return llvm::make_error<llvm::StringError>("could not get stderr", 187 llvm::inconvertibleErrorCode()); 188 } 189 190 lua_pop(m_lua_state, 1); 191 return llvm::Error::success(); 192 } 193