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|
/*
** Error handling.
** Copyright (C) 2005-2022 Mike Pall. See Copyright Notice in luajit.h
*/
#define lj_err_c
#define LUA_CORE
#include "lj_obj.h"
#include "lj_err.h"
#include "lj_debug.h"
#include "lj_str.h"
#include "lj_func.h"
#include "lj_state.h"
#include "lj_frame.h"
#include "lj_ff.h"
#include "lj_trace.h"
#include "lj_vm.h"
/*
** LuaJIT can either use internal or external frame unwinding:
**
** - Internal frame unwinding (INT) is free-standing and doesn't require
** any OS or library support.
**
** - External frame unwinding (EXT) uses the system-provided unwind handler.
**
** Pros and Cons:
**
** - EXT requires unwind tables for *all* functions on the C stack between
** the pcall/catch and the error/throw. This is the default on x64,
** but needs to be manually enabled on x86/PPC for non-C++ code.
**
** - INT is faster when actually throwing errors (but this happens rarely).
** Setting up error handlers is zero-cost in any case.
**
** - EXT provides full interoperability with C++ exceptions. You can throw
** Lua errors or C++ exceptions through a mix of Lua frames and C++ frames.
** C++ destructors are called as needed. C++ exceptions caught by pcall
** are converted to the string "C++ exception". Lua errors can be caught
** with catch (...) in C++.
**
** - INT has only limited support for automatically catching C++ exceptions
** on POSIX systems using DWARF2 stack unwinding. Other systems may use
** the wrapper function feature. Lua errors thrown through C++ frames
** cannot be caught by C++ code and C++ destructors are not run.
**
** EXT is the default on x64 systems, INT is the default on all other systems.
**
** EXT can be manually enabled on POSIX systems using GCC and DWARF2 stack
** unwinding with -DLUAJIT_UNWIND_EXTERNAL. *All* C code must be compiled
** with -funwind-tables (or -fexceptions). This includes LuaJIT itself (set
** TARGET_CFLAGS), all of your C/Lua binding code, all loadable C modules
** and all C libraries that have callbacks which may be used to call back
** into Lua. C++ code must *not* be compiled with -fno-exceptions.
**
** EXT cannot be enabled on WIN32 since system exceptions use code-driven SEH.
** EXT is mandatory on WIN64 since the calling convention has an abundance
** of callee-saved registers (rbx, rbp, rsi, rdi, r12-r15, xmm6-xmm15).
** The POSIX/x64 interpreter only saves r12/r13 for INT (e.g. PS4).
*/
#if defined(__GNUC__) && (LJ_TARGET_X64 || defined(LUAJIT_UNWIND_EXTERNAL)) && !LJ_NO_UNWIND
#define LJ_UNWIND_EXT 1
#elif LJ_TARGET_X64 && LJ_TARGET_WINDOWS
#define LJ_UNWIND_EXT 1
#endif
/* -- Error messages ------------------------------------------------------ */
/* Error message strings. */
LJ_DATADEF const char *lj_err_allmsg =
#define ERRDEF(name, msg) msg "\0"
#include "lj_errmsg.h"
;
/* -- Internal frame unwinding -------------------------------------------- */
/* Unwind Lua stack and move error message to new top. */
LJ_NOINLINE static void unwindstack(lua_State *L, TValue *top)
{
lj_func_closeuv(L, top);
if (top < L->top-1) {
copyTV(L, top, L->top-1);
L->top = top+1;
}
lj_state_relimitstack(L);
}
/* Unwind until stop frame. Optionally cleanup frames. */
static void *err_unwind(lua_State *L, void *stopcf, int errcode)
{
TValue *frame = L->base-1;
void *cf = L->cframe;
while (cf) {
int32_t nres = cframe_nres(cframe_raw(cf));
if (nres < 0) { /* C frame without Lua frame? */
TValue *top = restorestack(L, -nres);
if (frame < top) { /* Frame reached? */
if (errcode) {
L->cframe = cframe_prev(cf);
L->base = frame+1;
unwindstack(L, top);
}
return cf;
}
}
if (frame <= tvref(L->stack))
break;
switch (frame_typep(frame)) {
case FRAME_LUA: /* Lua frame. */
case FRAME_LUAP:
frame = frame_prevl(frame);
break;
case FRAME_C: /* C frame. */
#if LJ_HASFFI
unwind_c:
#endif
#if LJ_UNWIND_EXT
if (errcode) {
L->cframe = cframe_prev(cf);
L->base = frame_prevd(frame) + 1;
unwindstack(L, frame);
} else if (cf != stopcf) {
cf = cframe_prev(cf);
frame = frame_prevd(frame);
break;
}
return NULL; /* Continue unwinding. */
#else
UNUSED(stopcf);
cf = cframe_prev(cf);
frame = frame_prevd(frame);
break;
#endif
case FRAME_CP: /* Protected C frame. */
if (cframe_canyield(cf)) { /* Resume? */
if (errcode) {
hook_leave(G(L)); /* Assumes nobody uses coroutines inside hooks. */
L->cframe = NULL;
L->status = (uint8_t)errcode;
}
return cf;
}
if (errcode) {
L->cframe = cframe_prev(cf);
L->base = frame_prevd(frame) + 1;
unwindstack(L, frame);
}
return cf;
case FRAME_CONT: /* Continuation frame. */
#if LJ_HASFFI
if ((frame-1)->u32.lo == LJ_CONT_FFI_CALLBACK)
goto unwind_c;
#endif
/* fallthrough */
case FRAME_VARG: /* Vararg frame. */
frame = frame_prevd(frame);
break;
case FRAME_PCALL: /* FF pcall() frame. */
case FRAME_PCALLH: /* FF pcall() frame inside hook. */
if (errcode) {
if (errcode == LUA_YIELD) {
frame = frame_prevd(frame);
break;
}
if (frame_typep(frame) == FRAME_PCALL)
hook_leave(G(L));
L->cframe = cf;
L->base = frame_prevd(frame) + 1;
unwindstack(L, L->base);
}
return (void *)((intptr_t)cf | CFRAME_UNWIND_FF);
}
}
/* No C frame. */
if (errcode) {
L->cframe = NULL;
L->base = tvref(L->stack)+1;
unwindstack(L, L->base);
if (G(L)->panic)
G(L)->panic(L);
exit(EXIT_FAILURE);
}
return L; /* Anything non-NULL will do. */
}
/* -- External frame unwinding -------------------------------------------- */
#if defined(__GNUC__) && !LJ_NO_UNWIND && !LJ_ABI_WIN
/*
** We have to use our own definitions instead of the mandatory (!) unwind.h,
** since various OS, distros and compilers mess up the header installation.
*/
typedef struct _Unwind_Exception
{
uint64_t exclass;
void (*excleanup)(int, struct _Unwind_Exception *);
uintptr_t p1, p2;
} __attribute__((__aligned__)) _Unwind_Exception;
typedef struct _Unwind_Context _Unwind_Context;
#define _URC_OK 0
#define _URC_FATAL_PHASE1_ERROR 3
#define _URC_HANDLER_FOUND 6
#define _URC_INSTALL_CONTEXT 7
#define _URC_CONTINUE_UNWIND 8
#define _URC_FAILURE 9
#if !LJ_TARGET_ARM
extern uintptr_t _Unwind_GetCFA(_Unwind_Context *);
extern void _Unwind_SetGR(_Unwind_Context *, int, uintptr_t);
extern void _Unwind_SetIP(_Unwind_Context *, uintptr_t);
extern void _Unwind_DeleteException(_Unwind_Exception *);
extern int _Unwind_RaiseException(_Unwind_Exception *);
#define _UA_SEARCH_PHASE 1
#define _UA_CLEANUP_PHASE 2
#define _UA_HANDLER_FRAME 4
#define _UA_FORCE_UNWIND 8
#define LJ_UEXCLASS 0x4c55414a49543200ULL /* LUAJIT2\0 */
#define LJ_UEXCLASS_MAKE(c) (LJ_UEXCLASS | (uint64_t)(c))
#define LJ_UEXCLASS_CHECK(cl) (((cl) ^ LJ_UEXCLASS) <= 0xff)
#define LJ_UEXCLASS_ERRCODE(cl) ((int)((cl) & 0xff))
/* DWARF2 personality handler referenced from interpreter .eh_frame. */
LJ_FUNCA int lj_err_unwind_dwarf(int version, int actions,
uint64_t uexclass, _Unwind_Exception *uex, _Unwind_Context *ctx)
{
void *cf;
lua_State *L;
if (version != 1)
return _URC_FATAL_PHASE1_ERROR;
UNUSED(uexclass);
cf = (void *)_Unwind_GetCFA(ctx);
L = cframe_L(cf);
if ((actions & _UA_SEARCH_PHASE)) {
#if LJ_UNWIND_EXT
if (err_unwind(L, cf, 0) == NULL)
return _URC_CONTINUE_UNWIND;
#endif
if (!LJ_UEXCLASS_CHECK(uexclass)) {
setstrV(L, L->top++, lj_err_str(L, LJ_ERR_ERRCPP));
}
return _URC_HANDLER_FOUND;
}
if ((actions & _UA_CLEANUP_PHASE)) {
int errcode;
if (LJ_UEXCLASS_CHECK(uexclass)) {
errcode = LJ_UEXCLASS_ERRCODE(uexclass);
} else {
if ((actions & _UA_HANDLER_FRAME))
_Unwind_DeleteException(uex);
errcode = LUA_ERRRUN;
}
#if LJ_UNWIND_EXT
cf = err_unwind(L, cf, errcode);
if ((actions & _UA_FORCE_UNWIND)) {
return _URC_CONTINUE_UNWIND;
} else if (cf) {
_Unwind_SetGR(ctx, LJ_TARGET_EHRETREG, errcode);
_Unwind_SetIP(ctx, (uintptr_t)(cframe_unwind_ff(cf) ?
lj_vm_unwind_ff_eh :
lj_vm_unwind_c_eh));
return _URC_INSTALL_CONTEXT;
}
#if LJ_TARGET_X86ORX64
else if ((actions & _UA_HANDLER_FRAME)) {
/* Workaround for ancient libgcc bug. Still present in RHEL 5.5. :-/
** Real fix: http://gcc.gnu.org/viewcvs/trunk/gcc/unwind-dw2.c?r1=121165&r2=124837&pathrev=153877&diff_format=h
*/
_Unwind_SetGR(ctx, LJ_TARGET_EHRETREG, errcode);
_Unwind_SetIP(ctx, (uintptr_t)lj_vm_unwind_rethrow);
return _URC_INSTALL_CONTEXT;
}
#endif
#else
/* This is not the proper way to escape from the unwinder. We get away with
** it on non-x64 because the interpreter restores all callee-saved regs.
*/
lj_err_throw(L, errcode);
#endif
}
return _URC_CONTINUE_UNWIND;
}
#if LJ_UNWIND_EXT
static __thread _Unwind_Exception static_uex;
/* Raise DWARF2 exception. */
static void err_raise_ext(int errcode)
{
static_uex.exclass = LJ_UEXCLASS_MAKE(errcode);
static_uex.excleanup = NULL;
_Unwind_RaiseException(&static_uex);
}
#endif
#else
extern void _Unwind_DeleteException(void *);
extern int __gnu_unwind_frame (void *, _Unwind_Context *);
extern int _Unwind_VRS_Set(_Unwind_Context *, int, uint32_t, int, void *);
extern int _Unwind_VRS_Get(_Unwind_Context *, int, uint32_t, int, void *);
static inline uint32_t _Unwind_GetGR(_Unwind_Context *ctx, int r)
{
uint32_t v;
_Unwind_VRS_Get(ctx, 0, r, 0, &v);
return v;
}
static inline void _Unwind_SetGR(_Unwind_Context *ctx, int r, uint32_t v)
{
_Unwind_VRS_Set(ctx, 0, r, 0, &v);
}
#define _US_VIRTUAL_UNWIND_FRAME 0
#define _US_UNWIND_FRAME_STARTING 1
#define _US_ACTION_MASK 3
#define _US_FORCE_UNWIND 8
/* ARM unwinder personality handler referenced from interpreter .ARM.extab. */
LJ_FUNCA int lj_err_unwind_arm(int state, void *ucb, _Unwind_Context *ctx)
{
void *cf = (void *)_Unwind_GetGR(ctx, 13);
lua_State *L = cframe_L(cf);
if ((state & _US_ACTION_MASK) == _US_VIRTUAL_UNWIND_FRAME) {
setstrV(L, L->top++, lj_err_str(L, LJ_ERR_ERRCPP));
return _URC_HANDLER_FOUND;
}
if ((state&(_US_ACTION_MASK|_US_FORCE_UNWIND)) == _US_UNWIND_FRAME_STARTING) {
_Unwind_DeleteException(ucb);
_Unwind_SetGR(ctx, 15, (uint32_t)(void *)lj_err_throw);
_Unwind_SetGR(ctx, 0, (uint32_t)L);
_Unwind_SetGR(ctx, 1, (uint32_t)LUA_ERRRUN);
return _URC_INSTALL_CONTEXT;
}
if (__gnu_unwind_frame(ucb, ctx) != _URC_OK)
return _URC_FAILURE;
return _URC_CONTINUE_UNWIND;
}
#endif
#elif LJ_TARGET_X64 && LJ_ABI_WIN
/*
** Someone in Redmond owes me several days of my life. A lot of this is
** undocumented or just plain wrong on MSDN. Some of it can be gathered
** from 3rd party docs or must be found by trial-and-error. They really
** don't want you to write your own language-specific exception handler
** or to interact gracefully with MSVC. :-(
**
** Apparently MSVC doesn't call C++ destructors for foreign exceptions
** unless you compile your C++ code with /EHa. Unfortunately this means
** catch (...) also catches things like access violations. The use of
** _set_se_translator doesn't really help, because it requires /EHa, too.
*/
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
/* Taken from: http://www.nynaeve.net/?p=99 */
typedef struct UndocumentedDispatcherContext {
ULONG64 ControlPc;
ULONG64 ImageBase;
PRUNTIME_FUNCTION FunctionEntry;
ULONG64 EstablisherFrame;
ULONG64 TargetIp;
PCONTEXT ContextRecord;
void (*LanguageHandler)(void);
PVOID HandlerData;
PUNWIND_HISTORY_TABLE HistoryTable;
ULONG ScopeIndex;
ULONG Fill0;
} UndocumentedDispatcherContext;
/* Another wild guess. */
extern void __DestructExceptionObject(EXCEPTION_RECORD *rec, int nothrow);
#ifdef MINGW_SDK_INIT
/* Workaround for broken MinGW64 declaration. */
VOID RtlUnwindEx_FIXED(PVOID,PVOID,PVOID,PVOID,PVOID,PVOID) asm("RtlUnwindEx");
#define RtlUnwindEx RtlUnwindEx_FIXED
#endif
#define LJ_MSVC_EXCODE ((DWORD)0xe06d7363)
#define LJ_GCC_EXCODE ((DWORD)0x20474343)
#define LJ_EXCODE ((DWORD)0xe24c4a00)
#define LJ_EXCODE_MAKE(c) (LJ_EXCODE | (DWORD)(c))
#define LJ_EXCODE_CHECK(cl) (((cl) ^ LJ_EXCODE) <= 0xff)
#define LJ_EXCODE_ERRCODE(cl) ((int)((cl) & 0xff))
/* Win64 exception handler for interpreter frame. */
LJ_FUNCA EXCEPTION_DISPOSITION lj_err_unwind_win64(EXCEPTION_RECORD *rec,
void *cf, CONTEXT *ctx, UndocumentedDispatcherContext *dispatch)
{
lua_State *L = cframe_L(cf);
int errcode = LJ_EXCODE_CHECK(rec->ExceptionCode) ?
LJ_EXCODE_ERRCODE(rec->ExceptionCode) : LUA_ERRRUN;
if ((rec->ExceptionFlags & 6)) { /* EH_UNWINDING|EH_EXIT_UNWIND */
/* Unwind internal frames. */
err_unwind(L, cf, errcode);
} else {
void *cf2 = err_unwind(L, cf, 0);
if (cf2) { /* We catch it, so start unwinding the upper frames. */
if (rec->ExceptionCode == LJ_MSVC_EXCODE ||
rec->ExceptionCode == LJ_GCC_EXCODE) {
#if LJ_TARGET_WINDOWS
__DestructExceptionObject(rec, 1);
#endif
setstrV(L, L->top++, lj_err_str(L, LJ_ERR_ERRCPP));
} else if (!LJ_EXCODE_CHECK(rec->ExceptionCode)) {
/* Don't catch access violations etc. */
return ExceptionContinueSearch;
}
/* Unwind the stack and call all handlers for all lower C frames
** (including ourselves) again with EH_UNWINDING set. Then set
** rsp = cf, rax = errcode and jump to the specified target.
*/
RtlUnwindEx(cf, (void *)((cframe_unwind_ff(cf2) && errcode != LUA_YIELD) ?
lj_vm_unwind_ff_eh :
lj_vm_unwind_c_eh),
rec, (void *)(uintptr_t)errcode, ctx, dispatch->HistoryTable);
/* RtlUnwindEx should never return. */
}
}
return ExceptionContinueSearch;
}
/* Raise Windows exception. */
static void err_raise_ext(int errcode)
{
RaiseException(LJ_EXCODE_MAKE(errcode), 1 /* EH_NONCONTINUABLE */, 0, NULL);
}
#endif
/* -- Error handling ------------------------------------------------------ */
/* Throw error. Find catch frame, unwind stack and continue. */
LJ_NOINLINE void LJ_FASTCALL lj_err_throw(lua_State *L, int errcode)
{
global_State *g = G(L);
lj_trace_abort(g);
setgcrefnull(g->jit_L);
L->status = 0;
#if LJ_UNWIND_EXT
err_raise_ext(errcode);
/*
** A return from this function signals a corrupt C stack that cannot be
** unwound. We have no choice but to call the panic function and exit.
**
** Usually this is caused by a C function without unwind information.
** This should never happen on x64, but may happen if you've manually
** enabled LUAJIT_UNWIND_EXTERNAL and forgot to recompile *every*
** non-C++ file with -funwind-tables.
*/
if (G(L)->panic)
G(L)->panic(L);
#else
{
void *cf = err_unwind(L, NULL, errcode);
if (cframe_unwind_ff(cf))
lj_vm_unwind_ff(cframe_raw(cf));
else
lj_vm_unwind_c(cframe_raw(cf), errcode);
}
#endif
exit(EXIT_FAILURE);
}
/* Return string object for error message. */
LJ_NOINLINE GCstr *lj_err_str(lua_State *L, ErrMsg em)
{
return lj_str_newz(L, err2msg(em));
}
/* Out-of-memory error. */
LJ_NOINLINE void lj_err_mem(lua_State *L)
{
if (L->status == LUA_ERRERR+1) /* Don't touch the stack during lua_open. */
lj_vm_unwind_c(L->cframe, LUA_ERRMEM);
setstrV(L, L->top++, lj_err_str(L, LJ_ERR_ERRMEM));
lj_err_throw(L, LUA_ERRMEM);
}
/* Find error function for runtime errors. Requires an extra stack traversal. */
static ptrdiff_t finderrfunc(lua_State *L)
{
cTValue *frame = L->base-1, *bot = tvref(L->stack);
void *cf = L->cframe;
while (frame > bot && cf) {
while (cframe_nres(cframe_raw(cf)) < 0) { /* cframe without frame? */
if (frame >= restorestack(L, -cframe_nres(cf)))
break;
if (cframe_errfunc(cf) >= 0) /* Error handler not inherited (-1)? */
return cframe_errfunc(cf);
cf = cframe_prev(cf); /* Else unwind cframe and continue searching. */
if (cf == NULL)
return 0;
}
switch (frame_typep(frame)) {
case FRAME_LUA:
case FRAME_LUAP:
frame = frame_prevl(frame);
break;
case FRAME_C:
cf = cframe_prev(cf);
/* fallthrough */
case FRAME_VARG:
frame = frame_prevd(frame);
break;
case FRAME_CONT:
#if LJ_HASFFI
if ((frame-1)->u32.lo == LJ_CONT_FFI_CALLBACK)
cf = cframe_prev(cf);
#endif
frame = frame_prevd(frame);
break;
case FRAME_CP:
if (cframe_canyield(cf)) return 0;
if (cframe_errfunc(cf) >= 0)
return cframe_errfunc(cf);
cf = cframe_prev(cf);
frame = frame_prevd(frame);
break;
case FRAME_PCALL:
case FRAME_PCALLH:
if (frame_ftsz(frame) >= (ptrdiff_t)(2*sizeof(TValue))) /* xpcall? */
return savestack(L, frame-1); /* Point to xpcall's errorfunc. */
return 0;
default:
lua_assert(0);
return 0;
}
}
return 0;
}
/* Runtime error. */
LJ_NOINLINE void LJ_FASTCALL lj_err_run(lua_State *L)
{
ptrdiff_t ef = finderrfunc(L);
if (ef) {
TValue *errfunc = restorestack(L, ef);
TValue *top = L->top;
lj_trace_abort(G(L));
if (!tvisfunc(errfunc) || L->status == LUA_ERRERR) {
setstrV(L, top-1, lj_err_str(L, LJ_ERR_ERRERR));
lj_err_throw(L, LUA_ERRERR);
}
L->status = LUA_ERRERR;
copyTV(L, top, top-1);
copyTV(L, top-1, errfunc);
L->top = top+1;
lj_vm_call(L, top, 1+1); /* Stack: |errfunc|msg| -> |msg| */
}
lj_err_throw(L, LUA_ERRRUN);
}
/* Formatted runtime error message. */
LJ_NORET LJ_NOINLINE static void err_msgv(lua_State *L, ErrMsg em, ...)
{
const char *msg;
va_list argp;
va_start(argp, em);
if (curr_funcisL(L)) L->top = curr_topL(L);
msg = lj_str_pushvf(L, err2msg(em), argp);
va_end(argp);
lj_debug_addloc(L, msg, L->base-1, NULL);
lj_err_run(L);
}
/* Non-vararg variant for better calling conventions. */
LJ_NOINLINE void lj_err_msg(lua_State *L, ErrMsg em)
{
err_msgv(L, em);
}
/* Lexer error. */
LJ_NOINLINE void lj_err_lex(lua_State *L, GCstr *src, const char *tok,
BCLine line, ErrMsg em, va_list argp)
{
char buff[LUA_IDSIZE];
const char *msg;
lj_debug_shortname(buff, src);
msg = lj_str_pushvf(L, err2msg(em), argp);
msg = lj_str_pushf(L, "%s:%d: %s", buff, line, msg);
if (tok)
lj_str_pushf(L, err2msg(LJ_ERR_XNEAR), msg, tok);
lj_err_throw(L, LUA_ERRSYNTAX);
}
/* Typecheck error for operands. */
LJ_NOINLINE void lj_err_optype(lua_State *L, cTValue *o, ErrMsg opm)
{
const char *tname = lj_typename(o);
const char *opname = err2msg(opm);
if (curr_funcisL(L)) {
GCproto *pt = curr_proto(L);
const BCIns *pc = cframe_Lpc(L) - 1;
const char *oname = NULL;
const char *kind = lj_debug_slotname(pt, pc, (BCReg)(o-L->base), &oname);
if (kind)
err_msgv(L, LJ_ERR_BADOPRT, opname, kind, oname, tname);
}
err_msgv(L, LJ_ERR_BADOPRV, opname, tname);
}
/* Typecheck error for ordered comparisons. */
LJ_NOINLINE void lj_err_comp(lua_State *L, cTValue *o1, cTValue *o2)
{
const char *t1 = lj_typename(o1);
const char *t2 = lj_typename(o2);
err_msgv(L, t1 == t2 ? LJ_ERR_BADCMPV : LJ_ERR_BADCMPT, t1, t2);
/* This assumes the two "boolean" entries are commoned by the C compiler. */
}
/* Typecheck error for __call. */
LJ_NOINLINE void lj_err_optype_call(lua_State *L, TValue *o)
{
/* Gross hack if lua_[p]call or pcall/xpcall fail for a non-callable object:
** L->base still points to the caller. So add a dummy frame with L instead
** of a function. See lua_getstack().
*/
const BCIns *pc = cframe_Lpc(L);
if (((ptrdiff_t)pc & FRAME_TYPE) != FRAME_LUA) {
const char *tname = lj_typename(o);
setframe_pc(o, pc);
setframe_gc(o, obj2gco(L));
L->top = L->base = o+1;
err_msgv(L, LJ_ERR_BADCALL, tname);
}
lj_err_optype(L, o, LJ_ERR_OPCALL);
}
/* Error in context of caller. */
LJ_NOINLINE void lj_err_callermsg(lua_State *L, const char *msg)
{
TValue *frame = L->base-1;
TValue *pframe = NULL;
if (frame_islua(frame)) {
pframe = frame_prevl(frame);
} else if (frame_iscont(frame)) {
#if LJ_HASFFI
if ((frame-1)->u32.lo == LJ_CONT_FFI_CALLBACK) {
pframe = frame;
frame = NULL;
} else
#endif
{
pframe = frame_prevd(frame);
#if LJ_HASFFI
/* Remove frame for FFI metamethods. */
if (frame_func(frame)->c.ffid >= FF_ffi_meta___index &&
frame_func(frame)->c.ffid <= FF_ffi_meta___tostring) {
L->base = pframe+1;
L->top = frame;
setcframe_pc(cframe_raw(L->cframe), frame_contpc(frame));
}
#endif
}
}
lj_debug_addloc(L, msg, pframe, frame);
lj_err_run(L);
}
/* Formatted error in context of caller. */
LJ_NOINLINE void lj_err_callerv(lua_State *L, ErrMsg em, ...)
{
const char *msg;
va_list argp;
va_start(argp, em);
msg = lj_str_pushvf(L, err2msg(em), argp);
va_end(argp);
lj_err_callermsg(L, msg);
}
/* Error in context of caller. */
LJ_NOINLINE void lj_err_caller(lua_State *L, ErrMsg em)
{
lj_err_callermsg(L, err2msg(em));
}
/* Argument error message. */
LJ_NORET LJ_NOINLINE static void err_argmsg(lua_State *L, int narg,
const char *msg)
{
const char *fname = "?";
const char *ftype = lj_debug_funcname(L, L->base - 1, &fname);
if (narg < 0 && narg > LUA_REGISTRYINDEX)
narg = (int)(L->top - L->base) + narg + 1;
if (ftype && ftype[3] == 'h' && --narg == 0) /* Check for "method". */
msg = lj_str_pushf(L, err2msg(LJ_ERR_BADSELF), fname, msg);
else
msg = lj_str_pushf(L, err2msg(LJ_ERR_BADARG), narg, fname, msg);
lj_err_callermsg(L, msg);
}
/* Formatted argument error. */
LJ_NOINLINE void lj_err_argv(lua_State *L, int narg, ErrMsg em, ...)
{
const char *msg;
va_list argp;
va_start(argp, em);
msg = lj_str_pushvf(L, err2msg(em), argp);
va_end(argp);
err_argmsg(L, narg, msg);
}
/* Argument error. */
LJ_NOINLINE void lj_err_arg(lua_State *L, int narg, ErrMsg em)
{
err_argmsg(L, narg, err2msg(em));
}
/* Typecheck error for arguments. */
LJ_NOINLINE void lj_err_argtype(lua_State *L, int narg, const char *xname)
{
const char *tname, *msg;
if (narg <= LUA_REGISTRYINDEX) {
if (narg >= LUA_GLOBALSINDEX) {
tname = lj_obj_itypename[~LJ_TTAB];
} else {
GCfunc *fn = curr_func(L);
int idx = LUA_GLOBALSINDEX - narg;
if (idx <= fn->c.nupvalues)
tname = lj_typename(&fn->c.upvalue[idx-1]);
else
tname = lj_obj_typename[0];
}
} else {
TValue *o = narg < 0 ? L->top + narg : L->base + narg-1;
tname = o < L->top ? lj_typename(o) : lj_obj_typename[0];
}
msg = lj_str_pushf(L, err2msg(LJ_ERR_BADTYPE), xname, tname);
err_argmsg(L, narg, msg);
}
/* Typecheck error for arguments. */
LJ_NOINLINE void lj_err_argt(lua_State *L, int narg, int tt)
{
lj_err_argtype(L, narg, lj_obj_typename[tt+1]);
}
/* -- Public error handling API ------------------------------------------- */
LUA_API lua_CFunction lua_atpanic(lua_State *L, lua_CFunction panicf)
{
lua_CFunction old = G(L)->panic;
G(L)->panic = panicf;
return old;
}
/* Forwarders for the public API (C calling convention and no LJ_NORET). */
LUA_API int lua_error(lua_State *L)
{
lj_err_run(L);
return 0; /* unreachable */
}
LUALIB_API int luaL_argerror(lua_State *L, int narg, const char *msg)
{
err_argmsg(L, narg, msg);
return 0; /* unreachable */
}
LUALIB_API int luaL_typerror(lua_State *L, int narg, const char *xname)
{
lj_err_argtype(L, narg, xname);
return 0; /* unreachable */
}
LUALIB_API void luaL_where(lua_State *L, int level)
{
int size;
cTValue *frame = lj_debug_frame(L, level, &size);
lj_debug_addloc(L, "", frame, size ? frame+size : NULL);
}
LUALIB_API int luaL_error(lua_State *L, const char *fmt, ...)
{
const char *msg;
va_list argp;
va_start(argp, fmt);
msg = lj_str_pushvf(L, fmt, argp);
va_end(argp);
lj_err_callermsg(L, msg);
return 0; /* unreachable */
}
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