| 1 | /* |
| 2 | ** Error handling. |
| 3 | ** Copyright (C) 2005-2014 Mike Pall. See Copyright Notice in luajit.h |
| 4 | */ |
| 5 | |
| 6 | #define lj_err_c |
| 7 | #define LUA_CORE |
| 8 | |
| 9 | #include "lj_obj.h" |
| 10 | #include "lj_err.h" |
| 11 | #include "lj_debug.h" |
| 12 | #include "lj_str.h" |
| 13 | #include "lj_func.h" |
| 14 | #include "lj_state.h" |
| 15 | #include "lj_frame.h" |
| 16 | #include "lj_ff.h" |
| 17 | #include "lj_trace.h" |
| 18 | #include "lj_vm.h" |
| 19 | |
| 20 | /* |
| 21 | ** LuaJIT can either use internal or external frame unwinding: |
| 22 | ** |
| 23 | ** - Internal frame unwinding (INT) is free-standing and doesn't require |
| 24 | ** any OS or library support. |
| 25 | ** |
| 26 | ** - External frame unwinding (EXT) uses the system-provided unwind handler. |
| 27 | ** |
| 28 | ** Pros and Cons: |
| 29 | ** |
| 30 | ** - EXT requires unwind tables for *all* functions on the C stack between |
| 31 | ** the pcall/catch and the error/throw. This is the default on x64, |
| 32 | ** but needs to be manually enabled on x86/PPC for non-C++ code. |
| 33 | ** |
| 34 | ** - INT is faster when actually throwing errors (but this happens rarely). |
| 35 | ** Setting up error handlers is zero-cost in any case. |
| 36 | ** |
| 37 | ** - EXT provides full interoperability with C++ exceptions. You can throw |
| 38 | ** Lua errors or C++ exceptions through a mix of Lua frames and C++ frames. |
| 39 | ** C++ destructors are called as needed. C++ exceptions caught by pcall |
| 40 | ** are converted to the string "C++ exception". Lua errors can be caught |
| 41 | ** with catch (...) in C++. |
| 42 | ** |
| 43 | ** - INT has only limited support for automatically catching C++ exceptions |
| 44 | ** on POSIX systems using DWARF2 stack unwinding. Other systems may use |
| 45 | ** the wrapper function feature. Lua errors thrown through C++ frames |
| 46 | ** cannot be caught by C++ code and C++ destructors are not run. |
| 47 | ** |
| 48 | ** EXT is the default on x64 systems, INT is the default on all other systems. |
| 49 | ** |
| 50 | ** EXT can be manually enabled on POSIX systems using GCC and DWARF2 stack |
| 51 | ** unwinding with -DLUAJIT_UNWIND_EXTERNAL. *All* C code must be compiled |
| 52 | ** with -funwind-tables (or -fexceptions). This includes LuaJIT itself (set |
| 53 | ** TARGET_CFLAGS), all of your C/Lua binding code, all loadable C modules |
| 54 | ** and all C libraries that have callbacks which may be used to call back |
| 55 | ** into Lua. C++ code must *not* be compiled with -fno-exceptions. |
| 56 | ** |
| 57 | ** EXT cannot be enabled on WIN32 since system exceptions use code-driven SEH. |
| 58 | ** EXT is mandatory on WIN64 since the calling convention has an abundance |
| 59 | ** of callee-saved registers (rbx, rbp, rsi, rdi, r12-r15, xmm6-xmm15). |
| 60 | ** EXT is mandatory on POSIX/x64 since the interpreter doesn't save r12/r13. |
| 61 | */ |
| 62 | |
| 63 | #if defined(__GNUC__) && (LJ_TARGET_X64 || defined(LUAJIT_UNWIND_EXTERNAL)) |
| 64 | #define LJ_UNWIND_EXT 1 |
| 65 | #elif LJ_TARGET_X64 && LJ_TARGET_WINDOWS |
| 66 | #define LJ_UNWIND_EXT 1 |
| 67 | #endif |
| 68 | |
| 69 | /* -- Error messages ------------------------------------------------------ */ |
| 70 | |
| 71 | /* Error message strings. */ |
| 72 | LJ_DATADEF const char *lj_err_allmsg = |
| 73 | #define ERRDEF(name, msg) msg "\0" |
| 74 | #include "lj_errmsg.h" |
| 75 | ; |
| 76 | |
| 77 | /* -- Internal frame unwinding -------------------------------------------- */ |
| 78 | |
| 79 | /* Unwind Lua stack and move error message to new top. */ |
| 80 | LJ_NOINLINE static void unwindstack(lua_State *L, TValue *top) |
| 81 | { |
| 82 | lj_func_closeuv(L, top); |
| 83 | if (top < L->top-1) { |
| 84 | copyTV(L, top, L->top-1); |
| 85 | L->top = top+1; |
| 86 | } |
| 87 | lj_state_relimitstack(L); |
| 88 | } |
| 89 | |
| 90 | /* Unwind until stop frame. Optionally cleanup frames. */ |
| 91 | static void *err_unwind(lua_State *L, void *stopcf, int errcode) |
| 92 | { |
| 93 | TValue *frame = L->base-1; |
| 94 | void *cf = L->cframe; |
| 95 | while (cf) { |
| 96 | int32_t nres = cframe_nres(cframe_raw(cf)); |
| 97 | if (nres < 0) { /* C frame without Lua frame? */ |
| 98 | TValue *top = restorestack(L, -nres); |
| 99 | if (frame < top) { /* Frame reached? */ |
| 100 | if (errcode) { |
| 101 | L->cframe = cframe_prev(cf); |
| 102 | L->base = frame+1; |
| 103 | unwindstack(L, top); |
| 104 | } |
| 105 | return cf; |
| 106 | } |
| 107 | } |
| 108 | if (frame <= tvref(L->stack)) |
| 109 | break; |
| 110 | switch (frame_typep(frame)) { |
| 111 | case FRAME_LUA: /* Lua frame. */ |
| 112 | case FRAME_LUAP: |
| 113 | frame = frame_prevl(frame); |
| 114 | break; |
| 115 | case FRAME_C: /* C frame. */ |
| 116 | #if LJ_HASFFI |
| 117 | unwind_c: |
| 118 | #endif |
| 119 | #if LJ_UNWIND_EXT |
| 120 | if (errcode) { |
| 121 | L->cframe = cframe_prev(cf); |
| 122 | L->base = frame_prevd(frame) + 1; |
| 123 | unwindstack(L, frame); |
| 124 | } else if (cf != stopcf) { |
| 125 | cf = cframe_prev(cf); |
| 126 | frame = frame_prevd(frame); |
| 127 | break; |
| 128 | } |
| 129 | return NULL; /* Continue unwinding. */ |
| 130 | #else |
| 131 | UNUSED(stopcf); |
| 132 | cf = cframe_prev(cf); |
| 133 | frame = frame_prevd(frame); |
| 134 | break; |
| 135 | #endif |
| 136 | case FRAME_CP: /* Protected C frame. */ |
| 137 | if (cframe_canyield(cf)) { /* Resume? */ |
| 138 | if (errcode) { |
| 139 | hook_leave(G(L)); /* Assumes nobody uses coroutines inside hooks. */ |
| 140 | L->cframe = NULL; |
| 141 | L->status = (uint8_t)errcode; |
| 142 | } |
| 143 | return cf; |
| 144 | } |
| 145 | if (errcode) { |
| 146 | L->cframe = cframe_prev(cf); |
| 147 | L->base = frame_prevd(frame) + 1; |
| 148 | unwindstack(L, frame); |
| 149 | } |
| 150 | return cf; |
| 151 | case FRAME_CONT: /* Continuation frame. */ |
| 152 | #if LJ_HASFFI |
| 153 | if ((frame-1)->u32.lo == LJ_CONT_FFI_CALLBACK) |
| 154 | goto unwind_c; |
| 155 | #endif |
| 156 | case FRAME_VARG: /* Vararg frame. */ |
| 157 | frame = frame_prevd(frame); |
| 158 | break; |
| 159 | case FRAME_PCALL: /* FF pcall() frame. */ |
| 160 | case FRAME_PCALLH: /* FF pcall() frame inside hook. */ |
| 161 | if (errcode) { |
| 162 | if (errcode == LUA_YIELD) { |
| 163 | frame = frame_prevd(frame); |
| 164 | break; |
| 165 | } |
| 166 | if (frame_typep(frame) == FRAME_PCALL) |
| 167 | hook_leave(G(L)); |
| 168 | L->cframe = cf; |
| 169 | L->base = frame_prevd(frame) + 1; |
| 170 | unwindstack(L, L->base); |
| 171 | } |
| 172 | return (void *)((intptr_t)cf | CFRAME_UNWIND_FF); |
| 173 | } |
| 174 | } |
| 175 | /* No C frame. */ |
| 176 | if (errcode) { |
| 177 | L->cframe = NULL; |
| 178 | L->base = tvref(L->stack)+1; |
| 179 | unwindstack(L, L->base); |
| 180 | if (G(L)->panic) |
| 181 | G(L)->panic(L); |
| 182 | exit(EXIT_FAILURE); |
| 183 | } |
| 184 | return L; /* Anything non-NULL will do. */ |
| 185 | } |
| 186 | |
| 187 | /* -- External frame unwinding -------------------------------------------- */ |
| 188 | |
| 189 | #if defined(__GNUC__) && !LJ_NO_UNWIND && !LJ_TARGET_WINDOWS |
| 190 | |
| 191 | /* |
| 192 | ** We have to use our own definitions instead of the mandatory (!) unwind.h, |
| 193 | ** since various OS, distros and compilers mess up the header installation. |
| 194 | */ |
| 195 | |
| 196 | typedef struct _Unwind_Exception |
| 197 | { |
| 198 | uint64_t exclass; |
| 199 | void (*excleanup)(int, struct _Unwind_Exception *); |
| 200 | uintptr_t p1, p2; |
| 201 | } __attribute__((__aligned__)) _Unwind_Exception; |
| 202 | |
| 203 | typedef struct _Unwind_Context _Unwind_Context; |
| 204 | |
| 205 | #define _URC_OK 0 |
| 206 | #define _URC_FATAL_PHASE1_ERROR 3 |
| 207 | #define _URC_HANDLER_FOUND 6 |
| 208 | #define _URC_INSTALL_CONTEXT 7 |
| 209 | #define _URC_CONTINUE_UNWIND 8 |
| 210 | #define _URC_FAILURE 9 |
| 211 | |
| 212 | #if !LJ_TARGET_ARM |
| 213 | |
| 214 | extern uintptr_t _Unwind_GetCFA(_Unwind_Context *); |
| 215 | extern void _Unwind_SetGR(_Unwind_Context *, int, uintptr_t); |
| 216 | extern void _Unwind_SetIP(_Unwind_Context *, uintptr_t); |
| 217 | extern void _Unwind_DeleteException(_Unwind_Exception *); |
| 218 | extern int _Unwind_RaiseException(_Unwind_Exception *); |
| 219 | |
| 220 | #define _UA_SEARCH_PHASE 1 |
| 221 | #define _UA_CLEANUP_PHASE 2 |
| 222 | #define _UA_HANDLER_FRAME 4 |
| 223 | #define _UA_FORCE_UNWIND 8 |
| 224 | |
| 225 | #define LJ_UEXCLASS 0x4c55414a49543200ULL /* LUAJIT2\0 */ |
| 226 | #define LJ_UEXCLASS_MAKE(c) (LJ_UEXCLASS | (uint64_t)(c)) |
| 227 | #define LJ_UEXCLASS_CHECK(cl) (((cl) ^ LJ_UEXCLASS) <= 0xff) |
| 228 | #define LJ_UEXCLASS_ERRCODE(cl) ((int)((cl) & 0xff)) |
| 229 | |
| 230 | /* DWARF2 personality handler referenced from interpreter .eh_frame. */ |
| 231 | LJ_FUNCA int lj_err_unwind_dwarf(int version, int actions, |
| 232 | uint64_t uexclass, _Unwind_Exception *uex, _Unwind_Context *ctx) |
| 233 | { |
| 234 | void *cf; |
| 235 | lua_State *L; |
| 236 | if (version != 1) |
| 237 | return _URC_FATAL_PHASE1_ERROR; |
| 238 | UNUSED(uexclass); |
| 239 | cf = (void *)_Unwind_GetCFA(ctx); |
| 240 | L = cframe_L(cf); |
| 241 | if ((actions & _UA_SEARCH_PHASE)) { |
| 242 | #if LJ_UNWIND_EXT |
| 243 | if (err_unwind(L, cf, 0) == NULL) |
| 244 | return _URC_CONTINUE_UNWIND; |
| 245 | #endif |
| 246 | if (!LJ_UEXCLASS_CHECK(uexclass)) { |
| 247 | setstrV(L, L->top++, lj_err_str(L, LJ_ERR_ERRCPP)); |
| 248 | } |
| 249 | return _URC_HANDLER_FOUND; |
| 250 | } |
| 251 | if ((actions & _UA_CLEANUP_PHASE)) { |
| 252 | int errcode; |
| 253 | if (LJ_UEXCLASS_CHECK(uexclass)) { |
| 254 | errcode = LJ_UEXCLASS_ERRCODE(uexclass); |
| 255 | } else { |
| 256 | if ((actions & _UA_HANDLER_FRAME)) |
| 257 | _Unwind_DeleteException(uex); |
| 258 | errcode = LUA_ERRRUN; |
| 259 | } |
| 260 | #if LJ_UNWIND_EXT |
| 261 | cf = err_unwind(L, cf, errcode); |
| 262 | if ((actions & _UA_FORCE_UNWIND)) { |
| 263 | return _URC_CONTINUE_UNWIND; |
| 264 | } else if (cf) { |
| 265 | _Unwind_SetGR(ctx, LJ_TARGET_EHRETREG, errcode); |
| 266 | _Unwind_SetIP(ctx, (uintptr_t)(cframe_unwind_ff(cf) ? |
| 267 | lj_vm_unwind_ff_eh : |
| 268 | lj_vm_unwind_c_eh)); |
| 269 | return _URC_INSTALL_CONTEXT; |
| 270 | } |
| 271 | #if LJ_TARGET_X86ORX64 |
| 272 | else if ((actions & _UA_HANDLER_FRAME)) { |
| 273 | /* Workaround for ancient libgcc bug. Still present in RHEL 5.5. :-/ |
| 274 | ** Real fix: http://gcc.gnu.org/viewcvs/trunk/gcc/unwind-dw2.c?r1=121165&r2=124837&pathrev=153877&diff_format=h |
| 275 | */ |
| 276 | _Unwind_SetGR(ctx, LJ_TARGET_EHRETREG, errcode); |
| 277 | _Unwind_SetIP(ctx, (uintptr_t)lj_vm_unwind_rethrow); |
| 278 | return _URC_INSTALL_CONTEXT; |
| 279 | } |
| 280 | #endif |
| 281 | #else |
| 282 | /* This is not the proper way to escape from the unwinder. We get away with |
| 283 | ** it on non-x64 because the interpreter restores all callee-saved regs. |
| 284 | */ |
| 285 | lj_err_throw(L, errcode); |
| 286 | #endif |
| 287 | } |
| 288 | return _URC_CONTINUE_UNWIND; |
| 289 | } |
| 290 | |
| 291 | #if LJ_UNWIND_EXT |
| 292 | #if LJ_TARGET_OSX || defined(__OpenBSD__) |
| 293 | /* Sorry, no thread safety for OSX. Complain to Apple, not me. */ |
| 294 | static _Unwind_Exception static_uex; |
| 295 | #else |
| 296 | static __thread _Unwind_Exception static_uex; |
| 297 | #endif |
| 298 | |
| 299 | /* Raise DWARF2 exception. */ |
| 300 | static void err_raise_ext(int errcode) |
| 301 | { |
| 302 | static_uex.exclass = LJ_UEXCLASS_MAKE(errcode); |
| 303 | static_uex.excleanup = NULL; |
| 304 | _Unwind_RaiseException(&static_uex); |
| 305 | } |
| 306 | #endif |
| 307 | |
| 308 | #else |
| 309 | |
| 310 | extern void _Unwind_DeleteException(void *); |
| 311 | extern int __gnu_unwind_frame (void *, _Unwind_Context *); |
| 312 | extern int _Unwind_VRS_Set(_Unwind_Context *, int, uint32_t, int, void *); |
| 313 | extern int _Unwind_VRS_Get(_Unwind_Context *, int, uint32_t, int, void *); |
| 314 | |
| 315 | static inline uint32_t _Unwind_GetGR(_Unwind_Context *ctx, int r) |
| 316 | { |
| 317 | uint32_t v; |
| 318 | _Unwind_VRS_Get(ctx, 0, r, 0, &v); |
| 319 | return v; |
| 320 | } |
| 321 | |
| 322 | static inline void _Unwind_SetGR(_Unwind_Context *ctx, int r, uint32_t v) |
| 323 | { |
| 324 | _Unwind_VRS_Set(ctx, 0, r, 0, &v); |
| 325 | } |
| 326 | |
| 327 | #define _US_VIRTUAL_UNWIND_FRAME 0 |
| 328 | #define _US_UNWIND_FRAME_STARTING 1 |
| 329 | #define _US_ACTION_MASK 3 |
| 330 | #define _US_FORCE_UNWIND 8 |
| 331 | |
| 332 | /* ARM unwinder personality handler referenced from interpreter .ARM.extab. */ |
| 333 | LJ_FUNCA int lj_err_unwind_arm(int state, void *ucb, _Unwind_Context *ctx) |
| 334 | { |
| 335 | void *cf = (void *)_Unwind_GetGR(ctx, 13); |
| 336 | lua_State *L = cframe_L(cf); |
| 337 | if ((state & _US_ACTION_MASK) == _US_VIRTUAL_UNWIND_FRAME) { |
| 338 | setstrV(L, L->top++, lj_err_str(L, LJ_ERR_ERRCPP)); |
| 339 | return _URC_HANDLER_FOUND; |
| 340 | } |
| 341 | if ((state&(_US_ACTION_MASK|_US_FORCE_UNWIND)) == _US_UNWIND_FRAME_STARTING) { |
| 342 | _Unwind_DeleteException(ucb); |
| 343 | _Unwind_SetGR(ctx, 15, (uint32_t)(void *)lj_err_throw); |
| 344 | _Unwind_SetGR(ctx, 0, (uint32_t)L); |
| 345 | _Unwind_SetGR(ctx, 1, (uint32_t)LUA_ERRRUN); |
| 346 | return _URC_INSTALL_CONTEXT; |
| 347 | } |
| 348 | if (__gnu_unwind_frame(ucb, ctx) != _URC_OK) |
| 349 | return _URC_FAILURE; |
| 350 | return _URC_CONTINUE_UNWIND; |
| 351 | } |
| 352 | |
| 353 | #endif |
| 354 | |
| 355 | #elif LJ_TARGET_X64 && LJ_TARGET_WINDOWS |
| 356 | |
| 357 | /* |
| 358 | ** Someone in Redmond owes me several days of my life. A lot of this is |
| 359 | ** undocumented or just plain wrong on MSDN. Some of it can be gathered |
| 360 | ** from 3rd party docs or must be found by trial-and-error. They really |
| 361 | ** don't want you to write your own language-specific exception handler |
| 362 | ** or to interact gracefully with MSVC. :-( |
| 363 | ** |
| 364 | ** Apparently MSVC doesn't call C++ destructors for foreign exceptions |
| 365 | ** unless you compile your C++ code with /EHa. Unfortunately this means |
| 366 | ** catch (...) also catches things like access violations. The use of |
| 367 | ** _set_se_translator doesn't really help, because it requires /EHa, too. |
| 368 | */ |
| 369 | |
| 370 | #define WIN32_LEAN_AND_MEAN |
| 371 | #include <windows.h> |
| 372 | |
| 373 | /* Taken from: http://www.nynaeve.net/?p=99 */ |
| 374 | typedef struct UndocumentedDispatcherContext { |
| 375 | ULONG64 ControlPc; |
| 376 | ULONG64 ImageBase; |
| 377 | PRUNTIME_FUNCTION FunctionEntry; |
| 378 | ULONG64 EstablisherFrame; |
| 379 | ULONG64 TargetIp; |
| 380 | PCONTEXT ContextRecord; |
| 381 | PEXCEPTION_ROUTINE LanguageHandler; |
| 382 | PVOID HandlerData; |
| 383 | PUNWIND_HISTORY_TABLE HistoryTable; |
| 384 | ULONG ScopeIndex; |
| 385 | ULONG Fill0; |
| 386 | } UndocumentedDispatcherContext; |
| 387 | |
| 388 | /* Another wild guess. */ |
| 389 | extern void __DestructExceptionObject(EXCEPTION_RECORD *rec, int nothrow); |
| 390 | |
| 391 | #ifdef MINGW_SDK_INIT |
| 392 | /* Workaround for broken MinGW64 declaration. */ |
| 393 | VOID RtlUnwindEx_FIXED(PVOID,PVOID,PVOID,PVOID,PVOID,PVOID) asm("RtlUnwindEx" ); |
| 394 | #define RtlUnwindEx RtlUnwindEx_FIXED |
| 395 | #endif |
| 396 | |
| 397 | #define LJ_MSVC_EXCODE ((DWORD)0xe06d7363) |
| 398 | #define LJ_GCC_EXCODE ((DWORD)0x20474343) |
| 399 | |
| 400 | #define LJ_EXCODE ((DWORD)0xe24c4a00) |
| 401 | #define LJ_EXCODE_MAKE(c) (LJ_EXCODE | (DWORD)(c)) |
| 402 | #define LJ_EXCODE_CHECK(cl) (((cl) ^ LJ_EXCODE) <= 0xff) |
| 403 | #define LJ_EXCODE_ERRCODE(cl) ((int)((cl) & 0xff)) |
| 404 | |
| 405 | /* Win64 exception handler for interpreter frame. */ |
| 406 | LJ_FUNCA EXCEPTION_DISPOSITION lj_err_unwind_win64(EXCEPTION_RECORD *rec, |
| 407 | void *cf, CONTEXT *ctx, UndocumentedDispatcherContext *dispatch) |
| 408 | { |
| 409 | lua_State *L = cframe_L(cf); |
| 410 | int errcode = LJ_EXCODE_CHECK(rec->ExceptionCode) ? |
| 411 | LJ_EXCODE_ERRCODE(rec->ExceptionCode) : LUA_ERRRUN; |
| 412 | if ((rec->ExceptionFlags & 6)) { /* EH_UNWINDING|EH_EXIT_UNWIND */ |
| 413 | /* Unwind internal frames. */ |
| 414 | err_unwind(L, cf, errcode); |
| 415 | } else { |
| 416 | void *cf2 = err_unwind(L, cf, 0); |
| 417 | if (cf2) { /* We catch it, so start unwinding the upper frames. */ |
| 418 | if (rec->ExceptionCode == LJ_MSVC_EXCODE || |
| 419 | rec->ExceptionCode == LJ_GCC_EXCODE) { |
| 420 | __DestructExceptionObject(rec, 1); |
| 421 | setstrV(L, L->top++, lj_err_str(L, LJ_ERR_ERRCPP)); |
| 422 | } else if (!LJ_EXCODE_CHECK(rec->ExceptionCode)) { |
| 423 | /* Don't catch access violations etc. */ |
| 424 | return ExceptionContinueSearch; |
| 425 | } |
| 426 | /* Unwind the stack and call all handlers for all lower C frames |
| 427 | ** (including ourselves) again with EH_UNWINDING set. Then set |
| 428 | ** rsp = cf, rax = errcode and jump to the specified target. |
| 429 | */ |
| 430 | RtlUnwindEx(cf, (void *)((cframe_unwind_ff(cf2) && errcode != LUA_YIELD) ? |
| 431 | lj_vm_unwind_ff_eh : |
| 432 | lj_vm_unwind_c_eh), |
| 433 | rec, (void *)(uintptr_t)errcode, ctx, dispatch->HistoryTable); |
| 434 | /* RtlUnwindEx should never return. */ |
| 435 | } |
| 436 | } |
| 437 | return ExceptionContinueSearch; |
| 438 | } |
| 439 | |
| 440 | /* Raise Windows exception. */ |
| 441 | static void err_raise_ext(int errcode) |
| 442 | { |
| 443 | RaiseException(LJ_EXCODE_MAKE(errcode), 1 /* EH_NONCONTINUABLE */, 0, NULL); |
| 444 | } |
| 445 | |
| 446 | #endif |
| 447 | |
| 448 | /* -- Error handling ------------------------------------------------------ */ |
| 449 | |
| 450 | /* Throw error. Find catch frame, unwind stack and continue. */ |
| 451 | LJ_NOINLINE void LJ_FASTCALL lj_err_throw(lua_State *L, int errcode) |
| 452 | { |
| 453 | global_State *g = G(L); |
| 454 | lj_trace_abort(g); |
| 455 | setgcrefnull(g->jit_L); |
| 456 | L->status = 0; |
| 457 | #if LJ_UNWIND_EXT |
| 458 | err_raise_ext(errcode); |
| 459 | /* |
| 460 | ** A return from this function signals a corrupt C stack that cannot be |
| 461 | ** unwound. We have no choice but to call the panic function and exit. |
| 462 | ** |
| 463 | ** Usually this is caused by a C function without unwind information. |
| 464 | ** This should never happen on x64, but may happen if you've manually |
| 465 | ** enabled LUAJIT_UNWIND_EXTERNAL and forgot to recompile *every* |
| 466 | ** non-C++ file with -funwind-tables. |
| 467 | */ |
| 468 | if (G(L)->panic) |
| 469 | G(L)->panic(L); |
| 470 | #else |
| 471 | { |
| 472 | void *cf = err_unwind(L, NULL, errcode); |
| 473 | if (cframe_unwind_ff(cf)) |
| 474 | lj_vm_unwind_ff(cframe_raw(cf)); |
| 475 | else |
| 476 | lj_vm_unwind_c(cframe_raw(cf), errcode); |
| 477 | } |
| 478 | #endif |
| 479 | exit(EXIT_FAILURE); |
| 480 | } |
| 481 | |
| 482 | /* Return string object for error message. */ |
| 483 | LJ_NOINLINE GCstr *lj_err_str(lua_State *L, ErrMsg em) |
| 484 | { |
| 485 | return lj_str_newz(L, err2msg(em)); |
| 486 | } |
| 487 | |
| 488 | /* Out-of-memory error. */ |
| 489 | LJ_NOINLINE void lj_err_mem(lua_State *L) |
| 490 | { |
| 491 | if (L->status == LUA_ERRERR+1) /* Don't touch the stack during lua_open. */ |
| 492 | lj_vm_unwind_c(L->cframe, LUA_ERRMEM); |
| 493 | setstrV(L, L->top++, lj_err_str(L, LJ_ERR_ERRMEM)); |
| 494 | lj_err_throw(L, LUA_ERRMEM); |
| 495 | } |
| 496 | |
| 497 | /* Find error function for runtime errors. Requires an extra stack traversal. */ |
| 498 | static ptrdiff_t finderrfunc(lua_State *L) |
| 499 | { |
| 500 | cTValue *frame = L->base-1, *bot = tvref(L->stack); |
| 501 | void *cf = L->cframe; |
| 502 | while (frame > bot) { |
| 503 | lua_assert(cf != NULL); |
| 504 | while (cframe_nres(cframe_raw(cf)) < 0) { /* cframe without frame? */ |
| 505 | if (frame >= restorestack(L, -cframe_nres(cf))) |
| 506 | break; |
| 507 | if (cframe_errfunc(cf) >= 0) /* Error handler not inherited (-1)? */ |
| 508 | return cframe_errfunc(cf); |
| 509 | cf = cframe_prev(cf); /* Else unwind cframe and continue searching. */ |
| 510 | if (cf == NULL) |
| 511 | return 0; |
| 512 | } |
| 513 | switch (frame_typep(frame)) { |
| 514 | case FRAME_LUA: |
| 515 | case FRAME_LUAP: |
| 516 | frame = frame_prevl(frame); |
| 517 | break; |
| 518 | case FRAME_C: |
| 519 | cf = cframe_prev(cf); |
| 520 | /* fallthrough */ |
| 521 | case FRAME_CONT: |
| 522 | #if LJ_HASFFI |
| 523 | if ((frame-1)->u32.lo == LJ_CONT_FFI_CALLBACK) |
| 524 | cf = cframe_prev(cf); |
| 525 | #endif |
| 526 | case FRAME_VARG: |
| 527 | frame = frame_prevd(frame); |
| 528 | break; |
| 529 | case FRAME_CP: |
| 530 | if (cframe_canyield(cf)) return 0; |
| 531 | if (cframe_errfunc(cf) >= 0) |
| 532 | return cframe_errfunc(cf); |
| 533 | frame = frame_prevd(frame); |
| 534 | break; |
| 535 | case FRAME_PCALL: |
| 536 | case FRAME_PCALLH: |
| 537 | if (frame_ftsz(frame) >= (ptrdiff_t)(2*sizeof(TValue))) /* xpcall? */ |
| 538 | return savestack(L, frame-1); /* Point to xpcall's errorfunc. */ |
| 539 | return 0; |
| 540 | default: |
| 541 | lua_assert(0); |
| 542 | return 0; |
| 543 | } |
| 544 | } |
| 545 | return 0; |
| 546 | } |
| 547 | |
| 548 | /* Runtime error. */ |
| 549 | LJ_NOINLINE void lj_err_run(lua_State *L) |
| 550 | { |
| 551 | ptrdiff_t ef = finderrfunc(L); |
| 552 | if (ef) { |
| 553 | TValue *errfunc = restorestack(L, ef); |
| 554 | TValue *top = L->top; |
| 555 | lj_trace_abort(G(L)); |
| 556 | if (!tvisfunc(errfunc) || L->status == LUA_ERRERR) { |
| 557 | setstrV(L, top-1, lj_err_str(L, LJ_ERR_ERRERR)); |
| 558 | lj_err_throw(L, LUA_ERRERR); |
| 559 | } |
| 560 | L->status = LUA_ERRERR; |
| 561 | copyTV(L, top, top-1); |
| 562 | copyTV(L, top-1, errfunc); |
| 563 | L->top = top+1; |
| 564 | lj_vm_call(L, top, 1+1); /* Stack: |errfunc|msg| -> |msg| */ |
| 565 | } |
| 566 | lj_err_throw(L, LUA_ERRRUN); |
| 567 | } |
| 568 | |
| 569 | /* Formatted runtime error message. */ |
| 570 | LJ_NORET LJ_NOINLINE static void err_msgv(lua_State *L, ErrMsg em, ...) |
| 571 | { |
| 572 | const char *msg; |
| 573 | va_list argp; |
| 574 | va_start(argp, em); |
| 575 | if (curr_funcisL(L)) L->top = curr_topL(L); |
| 576 | msg = lj_str_pushvf(L, err2msg(em), argp); |
| 577 | va_end(argp); |
| 578 | lj_debug_addloc(L, msg, L->base-1, NULL); |
| 579 | lj_err_run(L); |
| 580 | } |
| 581 | |
| 582 | /* Non-vararg variant for better calling conventions. */ |
| 583 | LJ_NOINLINE void lj_err_msg(lua_State *L, ErrMsg em) |
| 584 | { |
| 585 | err_msgv(L, em); |
| 586 | } |
| 587 | |
| 588 | /* Lexer error. */ |
| 589 | LJ_NOINLINE void lj_err_lex(lua_State *L, GCstr *src, const char *tok, |
| 590 | BCLine line, ErrMsg em, va_list argp) |
| 591 | { |
| 592 | char buff[LUA_IDSIZE]; |
| 593 | const char *msg; |
| 594 | lj_debug_shortname(buff, src); |
| 595 | msg = lj_str_pushvf(L, err2msg(em), argp); |
| 596 | msg = lj_str_pushf(L, "%s:%d: %s" , buff, line, msg); |
| 597 | if (tok) |
| 598 | lj_str_pushf(L, err2msg(LJ_ERR_XNEAR), msg, tok); |
| 599 | lj_err_throw(L, LUA_ERRSYNTAX); |
| 600 | } |
| 601 | |
| 602 | /* Typecheck error for operands. */ |
| 603 | LJ_NOINLINE void lj_err_optype(lua_State *L, cTValue *o, ErrMsg opm) |
| 604 | { |
| 605 | const char *tname = lj_typename(o); |
| 606 | const char *opname = err2msg(opm); |
| 607 | if (curr_funcisL(L)) { |
| 608 | GCproto *pt = curr_proto(L); |
| 609 | const BCIns *pc = cframe_Lpc(L) - 1; |
| 610 | const char *oname = NULL; |
| 611 | const char *kind = lj_debug_slotname(pt, pc, (BCReg)(o-L->base), &oname); |
| 612 | if (kind) |
| 613 | err_msgv(L, LJ_ERR_BADOPRT, opname, kind, oname, tname); |
| 614 | } |
| 615 | err_msgv(L, LJ_ERR_BADOPRV, opname, tname); |
| 616 | } |
| 617 | |
| 618 | /* Typecheck error for ordered comparisons. */ |
| 619 | LJ_NOINLINE void lj_err_comp(lua_State *L, cTValue *o1, cTValue *o2) |
| 620 | { |
| 621 | const char *t1 = lj_typename(o1); |
| 622 | const char *t2 = lj_typename(o2); |
| 623 | err_msgv(L, t1 == t2 ? LJ_ERR_BADCMPV : LJ_ERR_BADCMPT, t1, t2); |
| 624 | /* This assumes the two "boolean" entries are commoned by the C compiler. */ |
| 625 | } |
| 626 | |
| 627 | /* Typecheck error for __call. */ |
| 628 | LJ_NOINLINE void lj_err_optype_call(lua_State *L, TValue *o) |
| 629 | { |
| 630 | /* Gross hack if lua_[p]call or pcall/xpcall fail for a non-callable object: |
| 631 | ** L->base still points to the caller. So add a dummy frame with L instead |
| 632 | ** of a function. See lua_getstack(). |
| 633 | */ |
| 634 | const BCIns *pc = cframe_Lpc(L); |
| 635 | if (((ptrdiff_t)pc & FRAME_TYPE) != FRAME_LUA) { |
| 636 | const char *tname = lj_typename(o); |
| 637 | setframe_pc(o, pc); |
| 638 | setframe_gc(o, obj2gco(L)); |
| 639 | L->top = L->base = o+1; |
| 640 | err_msgv(L, LJ_ERR_BADCALL, tname); |
| 641 | } |
| 642 | lj_err_optype(L, o, LJ_ERR_OPCALL); |
| 643 | } |
| 644 | |
| 645 | /* Error in context of caller. */ |
| 646 | LJ_NOINLINE void lj_err_callermsg(lua_State *L, const char *msg) |
| 647 | { |
| 648 | TValue *frame = L->base-1; |
| 649 | TValue *pframe = NULL; |
| 650 | if (frame_islua(frame)) { |
| 651 | pframe = frame_prevl(frame); |
| 652 | } else if (frame_iscont(frame)) { |
| 653 | #if LJ_HASFFI |
| 654 | if ((frame-1)->u32.lo == LJ_CONT_FFI_CALLBACK) { |
| 655 | pframe = frame; |
| 656 | frame = NULL; |
| 657 | } else |
| 658 | #endif |
| 659 | { |
| 660 | pframe = frame_prevd(frame); |
| 661 | #if LJ_HASFFI |
| 662 | /* Remove frame for FFI metamethods. */ |
| 663 | if (frame_func(frame)->c.ffid >= FF_ffi_meta___index && |
| 664 | frame_func(frame)->c.ffid <= FF_ffi_meta___tostring) { |
| 665 | L->base = pframe+1; |
| 666 | L->top = frame; |
| 667 | setcframe_pc(cframe_raw(L->cframe), frame_contpc(frame)); |
| 668 | } |
| 669 | #endif |
| 670 | } |
| 671 | } |
| 672 | lj_debug_addloc(L, msg, pframe, frame); |
| 673 | lj_err_run(L); |
| 674 | } |
| 675 | |
| 676 | /* Formatted error in context of caller. */ |
| 677 | LJ_NOINLINE void lj_err_callerv(lua_State *L, ErrMsg em, ...) |
| 678 | { |
| 679 | const char *msg; |
| 680 | va_list argp; |
| 681 | va_start(argp, em); |
| 682 | msg = lj_str_pushvf(L, err2msg(em), argp); |
| 683 | va_end(argp); |
| 684 | lj_err_callermsg(L, msg); |
| 685 | } |
| 686 | |
| 687 | /* Error in context of caller. */ |
| 688 | LJ_NOINLINE void lj_err_caller(lua_State *L, ErrMsg em) |
| 689 | { |
| 690 | lj_err_callermsg(L, err2msg(em)); |
| 691 | } |
| 692 | |
| 693 | /* Argument error message. */ |
| 694 | LJ_NORET LJ_NOINLINE static void err_argmsg(lua_State *L, int narg, |
| 695 | const char *msg) |
| 696 | { |
| 697 | const char *fname = "?" ; |
| 698 | const char *ftype = lj_debug_funcname(L, L->base - 1, &fname); |
| 699 | if (narg < 0 && narg > LUA_REGISTRYINDEX) |
| 700 | narg = (int)(L->top - L->base) + narg + 1; |
| 701 | if (ftype && ftype[3] == 'h' && --narg == 0) /* Check for "method". */ |
| 702 | msg = lj_str_pushf(L, err2msg(LJ_ERR_BADSELF), fname, msg); |
| 703 | else |
| 704 | msg = lj_str_pushf(L, err2msg(LJ_ERR_BADARG), narg, fname, msg); |
| 705 | lj_err_callermsg(L, msg); |
| 706 | } |
| 707 | |
| 708 | /* Formatted argument error. */ |
| 709 | LJ_NOINLINE void lj_err_argv(lua_State *L, int narg, ErrMsg em, ...) |
| 710 | { |
| 711 | const char *msg; |
| 712 | va_list argp; |
| 713 | va_start(argp, em); |
| 714 | msg = lj_str_pushvf(L, err2msg(em), argp); |
| 715 | va_end(argp); |
| 716 | err_argmsg(L, narg, msg); |
| 717 | } |
| 718 | |
| 719 | /* Argument error. */ |
| 720 | LJ_NOINLINE void lj_err_arg(lua_State *L, int narg, ErrMsg em) |
| 721 | { |
| 722 | err_argmsg(L, narg, err2msg(em)); |
| 723 | } |
| 724 | |
| 725 | /* Typecheck error for arguments. */ |
| 726 | LJ_NOINLINE void lj_err_argtype(lua_State *L, int narg, const char *xname) |
| 727 | { |
| 728 | TValue *o = narg < 0 ? L->top + narg : L->base + narg-1; |
| 729 | const char *tname = o < L->top ? lj_typename(o) : lj_obj_typename[0]; |
| 730 | const char *msg = lj_str_pushf(L, err2msg(LJ_ERR_BADTYPE), xname, tname); |
| 731 | err_argmsg(L, narg, msg); |
| 732 | } |
| 733 | |
| 734 | /* Typecheck error for arguments. */ |
| 735 | LJ_NOINLINE void lj_err_argt(lua_State *L, int narg, int tt) |
| 736 | { |
| 737 | lj_err_argtype(L, narg, lj_obj_typename[tt+1]); |
| 738 | } |
| 739 | |
| 740 | /* -- Public error handling API ------------------------------------------- */ |
| 741 | |
| 742 | LUA_API lua_CFunction lua_atpanic(lua_State *L, lua_CFunction panicf) |
| 743 | { |
| 744 | lua_CFunction old = G(L)->panic; |
| 745 | G(L)->panic = panicf; |
| 746 | return old; |
| 747 | } |
| 748 | |
| 749 | /* Forwarders for the public API (C calling convention and no LJ_NORET). */ |
| 750 | LUA_API int lua_error(lua_State *L) |
| 751 | { |
| 752 | lj_err_run(L); |
| 753 | return 0; /* unreachable */ |
| 754 | } |
| 755 | |
| 756 | LUALIB_API int luaL_argerror(lua_State *L, int narg, const char *msg) |
| 757 | { |
| 758 | err_argmsg(L, narg, msg); |
| 759 | return 0; /* unreachable */ |
| 760 | } |
| 761 | |
| 762 | LUALIB_API int luaL_typerror(lua_State *L, int narg, const char *xname) |
| 763 | { |
| 764 | lj_err_argtype(L, narg, xname); |
| 765 | return 0; /* unreachable */ |
| 766 | } |
| 767 | |
| 768 | LUALIB_API void luaL_where(lua_State *L, int level) |
| 769 | { |
| 770 | int size; |
| 771 | cTValue *frame = lj_debug_frame(L, level, &size); |
| 772 | lj_debug_addloc(L, "" , frame, size ? frame+size : NULL); |
| 773 | } |
| 774 | |
| 775 | LUALIB_API int luaL_error(lua_State *L, const char *fmt, ...) |
| 776 | { |
| 777 | const char *msg; |
| 778 | va_list argp; |
| 779 | va_start(argp, fmt); |
| 780 | msg = lj_str_pushvf(L, fmt, argp); |
| 781 | va_end(argp); |
| 782 | lj_err_callermsg(L, msg); |
| 783 | return 0; /* unreachable */ |
| 784 | } |
| 785 | |
| 786 | |