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 | |