diff options
Diffstat (limited to '3rdparty/lua/src/ldo.c')
| -rw-r--r-- | 3rdparty/lua/src/ldo.c | 802 |
1 files changed, 0 insertions, 802 deletions
diff --git a/3rdparty/lua/src/ldo.c b/3rdparty/lua/src/ldo.c deleted file mode 100644 index 90b695f..0000000 --- a/3rdparty/lua/src/ldo.c +++ /dev/null @@ -1,802 +0,0 @@ -/* -** $Id: ldo.c,v 2.157 2016/12/13 15:52:21 roberto Exp $ -** Stack and Call structure of Lua -** See Copyright Notice in lua.h -*/ - -#define ldo_c -#define LUA_CORE - -#include "lprefix.h" - - -#include <setjmp.h> -#include <stdlib.h> -#include <string.h> - -#include "lua.h" - -#include "lapi.h" -#include "ldebug.h" -#include "ldo.h" -#include "lfunc.h" -#include "lgc.h" -#include "lmem.h" -#include "lobject.h" -#include "lopcodes.h" -#include "lparser.h" -#include "lstate.h" -#include "lstring.h" -#include "ltable.h" -#include "ltm.h" -#include "lundump.h" -#include "lvm.h" -#include "lzio.h" - - - -#define errorstatus(s) ((s) > LUA_YIELD) - - -/* -** {====================================================== -** Error-recovery functions -** ======================================================= -*/ - -/* -** LUAI_THROW/LUAI_TRY define how Lua does exception handling. By -** default, Lua handles errors with exceptions when compiling as -** C++ code, with _longjmp/_setjmp when asked to use them, and with -** longjmp/setjmp otherwise. -*/ -#if !defined(LUAI_THROW) /* { */ - -#if defined(__cplusplus) && !defined(LUA_USE_LONGJMP) /* { */ - -/* C++ exceptions */ -#define LUAI_THROW(L,c) throw(c) -#define LUAI_TRY(L,c,a) \ - try { a } catch(...) { if ((c)->status == 0) (c)->status = -1; } -#define luai_jmpbuf int /* dummy variable */ - -#elif defined(LUA_USE_POSIX) /* }{ */ - -/* in POSIX, try _longjmp/_setjmp (more efficient) */ -#define LUAI_THROW(L,c) _longjmp((c)->b, 1) -#define LUAI_TRY(L,c,a) if (_setjmp((c)->b) == 0) { a } -#define luai_jmpbuf jmp_buf - -#else /* }{ */ - -/* ISO C handling with long jumps */ -#define LUAI_THROW(L,c) longjmp((c)->b, 1) -#define LUAI_TRY(L,c,a) if (setjmp((c)->b) == 0) { a } -#define luai_jmpbuf jmp_buf - -#endif /* } */ - -#endif /* } */ - - - -/* chain list of long jump buffers */ -struct lua_longjmp { - struct lua_longjmp *previous; - luai_jmpbuf b; - volatile int status; /* error code */ -}; - - -static void seterrorobj (lua_State *L, int errcode, StkId oldtop) { - switch (errcode) { - case LUA_ERRMEM: { /* memory error? */ - setsvalue2s(L, oldtop, G(L)->memerrmsg); /* reuse preregistered msg. */ - break; - } - case LUA_ERRERR: { - setsvalue2s(L, oldtop, luaS_newliteral(L, "error in error handling")); - break; - } - default: { - setobjs2s(L, oldtop, L->top - 1); /* error message on current top */ - break; - } - } - L->top = oldtop + 1; -} - - -l_noret luaD_throw (lua_State *L, int errcode) { - if (L->errorJmp) { /* thread has an error handler? */ - L->errorJmp->status = errcode; /* set status */ - LUAI_THROW(L, L->errorJmp); /* jump to it */ - } - else { /* thread has no error handler */ - global_State *g = G(L); - L->status = cast_byte(errcode); /* mark it as dead */ - if (g->mainthread->errorJmp) { /* main thread has a handler? */ - setobjs2s(L, g->mainthread->top++, L->top - 1); /* copy error obj. */ - luaD_throw(g->mainthread, errcode); /* re-throw in main thread */ - } - else { /* no handler at all; abort */ - if (g->panic) { /* panic function? */ - seterrorobj(L, errcode, L->top); /* assume EXTRA_STACK */ - if (L->ci->top < L->top) - L->ci->top = L->top; /* pushing msg. can break this invariant */ - lua_unlock(L); - g->panic(L); /* call panic function (last chance to jump out) */ - } - abort(); - } - } -} - - -int luaD_rawrunprotected (lua_State *L, Pfunc f, void *ud) { - unsigned short oldnCcalls = L->nCcalls; - struct lua_longjmp lj; - lj.status = LUA_OK; - lj.previous = L->errorJmp; /* chain new error handler */ - L->errorJmp = &lj; - LUAI_TRY(L, &lj, - (*f)(L, ud); - ); - L->errorJmp = lj.previous; /* restore old error handler */ - L->nCcalls = oldnCcalls; - return lj.status; -} - -/* }====================================================== */ - - -/* -** {================================================================== -** Stack reallocation -** =================================================================== -*/ -static void correctstack (lua_State *L, TValue *oldstack) { - CallInfo *ci; - UpVal *up; - L->top = (L->top - oldstack) + L->stack; - for (up = L->openupval; up != NULL; up = up->u.open.next) - up->v = (up->v - oldstack) + L->stack; - for (ci = L->ci; ci != NULL; ci = ci->previous) { - ci->top = (ci->top - oldstack) + L->stack; - ci->func = (ci->func - oldstack) + L->stack; - if (isLua(ci)) - ci->u.l.base = (ci->u.l.base - oldstack) + L->stack; - } -} - - -/* some space for error handling */ -#define ERRORSTACKSIZE (LUAI_MAXSTACK + 200) - - -void luaD_reallocstack (lua_State *L, int newsize) { - TValue *oldstack = L->stack; - int lim = L->stacksize; - lua_assert(newsize <= LUAI_MAXSTACK || newsize == ERRORSTACKSIZE); - lua_assert(L->stack_last - L->stack == L->stacksize - EXTRA_STACK); - luaM_reallocvector(L, L->stack, L->stacksize, newsize, TValue); - for (; lim < newsize; lim++) - setnilvalue(L->stack + lim); /* erase new segment */ - L->stacksize = newsize; - L->stack_last = L->stack + newsize - EXTRA_STACK; - correctstack(L, oldstack); -} - - -void luaD_growstack (lua_State *L, int n) { - int size = L->stacksize; - if (size > LUAI_MAXSTACK) /* error after extra size? */ - luaD_throw(L, LUA_ERRERR); - else { - int needed = cast_int(L->top - L->stack) + n + EXTRA_STACK; - int newsize = 2 * size; - if (newsize > LUAI_MAXSTACK) newsize = LUAI_MAXSTACK; - if (newsize < needed) newsize = needed; - if (newsize > LUAI_MAXSTACK) { /* stack overflow? */ - luaD_reallocstack(L, ERRORSTACKSIZE); - luaG_runerror(L, "stack overflow"); - } - else - luaD_reallocstack(L, newsize); - } -} - - -static int stackinuse (lua_State *L) { - CallInfo *ci; - StkId lim = L->top; - for (ci = L->ci; ci != NULL; ci = ci->previous) { - if (lim < ci->top) lim = ci->top; - } - lua_assert(lim <= L->stack_last); - return cast_int(lim - L->stack) + 1; /* part of stack in use */ -} - - -void luaD_shrinkstack (lua_State *L) { - int inuse = stackinuse(L); - int goodsize = inuse + (inuse / 8) + 2*EXTRA_STACK; - if (goodsize > LUAI_MAXSTACK) - goodsize = LUAI_MAXSTACK; /* respect stack limit */ - if (L->stacksize > LUAI_MAXSTACK) /* had been handling stack overflow? */ - luaE_freeCI(L); /* free all CIs (list grew because of an error) */ - else - luaE_shrinkCI(L); /* shrink list */ - /* if thread is currently not handling a stack overflow and its - good size is smaller than current size, shrink its stack */ - if (inuse <= (LUAI_MAXSTACK - EXTRA_STACK) && - goodsize < L->stacksize) - luaD_reallocstack(L, goodsize); - else /* don't change stack */ - condmovestack(L,{},{}); /* (change only for debugging) */ -} - - -void luaD_inctop (lua_State *L) { - luaD_checkstack(L, 1); - L->top++; -} - -/* }================================================================== */ - - -/* -** Call a hook for the given event. Make sure there is a hook to be -** called. (Both 'L->hook' and 'L->hookmask', which triggers this -** function, can be changed asynchronously by signals.) -*/ -void luaD_hook (lua_State *L, int event, int line) { - lua_Hook hook = L->hook; - if (hook && L->allowhook) { /* make sure there is a hook */ - CallInfo *ci = L->ci; - ptrdiff_t top = savestack(L, L->top); - ptrdiff_t ci_top = savestack(L, ci->top); - lua_Debug ar; - ar.event = event; - ar.currentline = line; - ar.i_ci = ci; - luaD_checkstack(L, LUA_MINSTACK); /* ensure minimum stack size */ - ci->top = L->top + LUA_MINSTACK; - lua_assert(ci->top <= L->stack_last); - L->allowhook = 0; /* cannot call hooks inside a hook */ - ci->callstatus |= CIST_HOOKED; - lua_unlock(L); - (*hook)(L, &ar); - lua_lock(L); - lua_assert(!L->allowhook); - L->allowhook = 1; - ci->top = restorestack(L, ci_top); - L->top = restorestack(L, top); - ci->callstatus &= ~CIST_HOOKED; - } -} - - -static void callhook (lua_State *L, CallInfo *ci) { - int hook = LUA_HOOKCALL; - ci->u.l.savedpc++; /* hooks assume 'pc' is already incremented */ - if (isLua(ci->previous) && - GET_OPCODE(*(ci->previous->u.l.savedpc - 1)) == OP_TAILCALL) { - ci->callstatus |= CIST_TAIL; - hook = LUA_HOOKTAILCALL; - } - luaD_hook(L, hook, -1); - ci->u.l.savedpc--; /* correct 'pc' */ -} - - -static StkId adjust_varargs (lua_State *L, Proto *p, int actual) { - int i; - int nfixargs = p->numparams; - StkId base, fixed; - /* move fixed parameters to final position */ - fixed = L->top - actual; /* first fixed argument */ - base = L->top; /* final position of first argument */ - for (i = 0; i < nfixargs && i < actual; i++) { - setobjs2s(L, L->top++, fixed + i); - setnilvalue(fixed + i); /* erase original copy (for GC) */ - } - for (; i < nfixargs; i++) - setnilvalue(L->top++); /* complete missing arguments */ - return base; -} - - -/* -** Check whether __call metafield of 'func' is a function. If so, put -** it in stack below original 'func' so that 'luaD_precall' can call -** it. Raise an error if __call metafield is not a function. -*/ -static void tryfuncTM (lua_State *L, StkId func) { - const TValue *tm = luaT_gettmbyobj(L, func, TM_CALL); - StkId p; - if (!ttisfunction(tm)) - luaG_typeerror(L, func, "call"); - /* Open a hole inside the stack at 'func' */ - for (p = L->top; p > func; p--) - setobjs2s(L, p, p-1); - L->top++; /* slot ensured by caller */ - setobj2s(L, func, tm); /* tag method is the new function to be called */ -} - - -/* -** Given 'nres' results at 'firstResult', move 'wanted' of them to 'res'. -** Handle most typical cases (zero results for commands, one result for -** expressions, multiple results for tail calls/single parameters) -** separated. -*/ -static int moveresults (lua_State *L, const TValue *firstResult, StkId res, - int nres, int wanted) { - switch (wanted) { /* handle typical cases separately */ - case 0: break; /* nothing to move */ - case 1: { /* one result needed */ - if (nres == 0) /* no results? */ - firstResult = luaO_nilobject; /* adjust with nil */ - setobjs2s(L, res, firstResult); /* move it to proper place */ - break; - } - case LUA_MULTRET: { - int i; - for (i = 0; i < nres; i++) /* move all results to correct place */ - setobjs2s(L, res + i, firstResult + i); - L->top = res + nres; - return 0; /* wanted == LUA_MULTRET */ - } - default: { - int i; - if (wanted <= nres) { /* enough results? */ - for (i = 0; i < wanted; i++) /* move wanted results to correct place */ - setobjs2s(L, res + i, firstResult + i); - } - else { /* not enough results; use all of them plus nils */ - for (i = 0; i < nres; i++) /* move all results to correct place */ - setobjs2s(L, res + i, firstResult + i); - for (; i < wanted; i++) /* complete wanted number of results */ - setnilvalue(res + i); - } - break; - } - } - L->top = res + wanted; /* top points after the last result */ - return 1; -} - - -/* -** Finishes a function call: calls hook if necessary, removes CallInfo, -** moves current number of results to proper place; returns 0 iff call -** wanted multiple (variable number of) results. -*/ -int luaD_poscall (lua_State *L, CallInfo *ci, StkId firstResult, int nres) { - StkId res; - int wanted = ci->nresults; - if (L->hookmask & (LUA_MASKRET | LUA_MASKLINE)) { - if (L->hookmask & LUA_MASKRET) { - ptrdiff_t fr = savestack(L, firstResult); /* hook may change stack */ - luaD_hook(L, LUA_HOOKRET, -1); - firstResult = restorestack(L, fr); - } - L->oldpc = ci->previous->u.l.savedpc; /* 'oldpc' for caller function */ - } - res = ci->func; /* res == final position of 1st result */ - L->ci = ci->previous; /* back to caller */ - /* move results to proper place */ - return moveresults(L, firstResult, res, nres, wanted); -} - - - -#define next_ci(L) (L->ci = (L->ci->next ? L->ci->next : luaE_extendCI(L))) - - -/* macro to check stack size, preserving 'p' */ -#define checkstackp(L,n,p) \ - luaD_checkstackaux(L, n, \ - ptrdiff_t t__ = savestack(L, p); /* save 'p' */ \ - luaC_checkGC(L), /* stack grow uses memory */ \ - p = restorestack(L, t__)) /* 'pos' part: restore 'p' */ - - -/* -** Prepares a function call: checks the stack, creates a new CallInfo -** entry, fills in the relevant information, calls hook if needed. -** If function is a C function, does the call, too. (Otherwise, leave -** the execution ('luaV_execute') to the caller, to allow stackless -** calls.) Returns true iff function has been executed (C function). -*/ -int luaD_precall (lua_State *L, StkId func, int nresults) { - lua_CFunction f; - CallInfo *ci; - switch (ttype(func)) { - case LUA_TCCL: /* C closure */ - f = clCvalue(func)->f; - goto Cfunc; - case LUA_TLCF: /* light C function */ - f = fvalue(func); - Cfunc: { - int n; /* number of returns */ - checkstackp(L, LUA_MINSTACK, func); /* ensure minimum stack size */ - ci = next_ci(L); /* now 'enter' new function */ - ci->nresults = nresults; - ci->func = func; - ci->top = L->top + LUA_MINSTACK; - lua_assert(ci->top <= L->stack_last); - ci->callstatus = 0; - if (L->hookmask & LUA_MASKCALL) - luaD_hook(L, LUA_HOOKCALL, -1); - lua_unlock(L); - n = (*f)(L); /* do the actual call */ - lua_lock(L); - api_checknelems(L, n); - luaD_poscall(L, ci, L->top - n, n); - return 1; - } - case LUA_TLCL: { /* Lua function: prepare its call */ - StkId base; - Proto *p = clLvalue(func)->p; - int n = cast_int(L->top - func) - 1; /* number of real arguments */ - int fsize = p->maxstacksize; /* frame size */ - checkstackp(L, fsize, func); - if (p->is_vararg) - base = adjust_varargs(L, p, n); - else { /* non vararg function */ - for (; n < p->numparams; n++) - setnilvalue(L->top++); /* complete missing arguments */ - base = func + 1; - } - ci = next_ci(L); /* now 'enter' new function */ - ci->nresults = nresults; - ci->func = func; - ci->u.l.base = base; - L->top = ci->top = base + fsize; - lua_assert(ci->top <= L->stack_last); - ci->u.l.savedpc = p->code; /* starting point */ - ci->callstatus = CIST_LUA; - if (L->hookmask & LUA_MASKCALL) - callhook(L, ci); - return 0; - } - default: { /* not a function */ - checkstackp(L, 1, func); /* ensure space for metamethod */ - tryfuncTM(L, func); /* try to get '__call' metamethod */ - return luaD_precall(L, func, nresults); /* now it must be a function */ - } - } -} - - -/* -** Check appropriate error for stack overflow ("regular" overflow or -** overflow while handling stack overflow). If 'nCalls' is larger than -** LUAI_MAXCCALLS (which means it is handling a "regular" overflow) but -** smaller than 9/8 of LUAI_MAXCCALLS, does not report an error (to -** allow overflow handling to work) -*/ -static void stackerror (lua_State *L) { - if (L->nCcalls == LUAI_MAXCCALLS) - luaG_runerror(L, "C stack overflow"); - else if (L->nCcalls >= (LUAI_MAXCCALLS + (LUAI_MAXCCALLS>>3))) - luaD_throw(L, LUA_ERRERR); /* error while handing stack error */ -} - - -/* -** Call a function (C or Lua). The function to be called is at *func. -** The arguments are on the stack, right after the function. -** When returns, all the results are on the stack, starting at the original -** function position. -*/ -void luaD_call (lua_State *L, StkId func, int nResults) { - if (++L->nCcalls >= LUAI_MAXCCALLS) - stackerror(L); - if (!luaD_precall(L, func, nResults)) /* is a Lua function? */ - luaV_execute(L); /* call it */ - L->nCcalls--; -} - - -/* -** Similar to 'luaD_call', but does not allow yields during the call -*/ -void luaD_callnoyield (lua_State *L, StkId func, int nResults) { - L->nny++; - luaD_call(L, func, nResults); - L->nny--; -} - - -/* -** Completes the execution of an interrupted C function, calling its -** continuation function. -*/ -static void finishCcall (lua_State *L, int status) { - CallInfo *ci = L->ci; - int n; - /* must have a continuation and must be able to call it */ - lua_assert(ci->u.c.k != NULL && L->nny == 0); - /* error status can only happen in a protected call */ - lua_assert((ci->callstatus & CIST_YPCALL) || status == LUA_YIELD); - if (ci->callstatus & CIST_YPCALL) { /* was inside a pcall? */ - ci->callstatus &= ~CIST_YPCALL; /* continuation is also inside it */ - L->errfunc = ci->u.c.old_errfunc; /* with the same error function */ - } - /* finish 'lua_callk'/'lua_pcall'; CIST_YPCALL and 'errfunc' already - handled */ - adjustresults(L, ci->nresults); - lua_unlock(L); - n = (*ci->u.c.k)(L, status, ci->u.c.ctx); /* call continuation function */ - lua_lock(L); - api_checknelems(L, n); - luaD_poscall(L, ci, L->top - n, n); /* finish 'luaD_precall' */ -} - - -/* -** Executes "full continuation" (everything in the stack) of a -** previously interrupted coroutine until the stack is empty (or another -** interruption long-jumps out of the loop). If the coroutine is -** recovering from an error, 'ud' points to the error status, which must -** be passed to the first continuation function (otherwise the default -** status is LUA_YIELD). -*/ -static void unroll (lua_State *L, void *ud) { - if (ud != NULL) /* error status? */ - finishCcall(L, *(int *)ud); /* finish 'lua_pcallk' callee */ - while (L->ci != &L->base_ci) { /* something in the stack */ - if (!isLua(L->ci)) /* C function? */ - finishCcall(L, LUA_YIELD); /* complete its execution */ - else { /* Lua function */ - luaV_finishOp(L); /* finish interrupted instruction */ - luaV_execute(L); /* execute down to higher C 'boundary' */ - } - } -} - - -/* -** Try to find a suspended protected call (a "recover point") for the -** given thread. -*/ -static CallInfo *findpcall (lua_State *L) { - CallInfo *ci; - for (ci = L->ci; ci != NULL; ci = ci->previous) { /* search for a pcall */ - if (ci->callstatus & CIST_YPCALL) - return ci; - } - return NULL; /* no pending pcall */ -} - - -/* -** Recovers from an error in a coroutine. Finds a recover point (if -** there is one) and completes the execution of the interrupted -** 'luaD_pcall'. If there is no recover point, returns zero. -*/ -static int recover (lua_State *L, int status) { - StkId oldtop; - CallInfo *ci = findpcall(L); - if (ci == NULL) return 0; /* no recovery point */ - /* "finish" luaD_pcall */ - oldtop = restorestack(L, ci->extra); - luaF_close(L, oldtop); - seterrorobj(L, status, oldtop); - L->ci = ci; - L->allowhook = getoah(ci->callstatus); /* restore original 'allowhook' */ - L->nny = 0; /* should be zero to be yieldable */ - luaD_shrinkstack(L); - L->errfunc = ci->u.c.old_errfunc; - return 1; /* continue running the coroutine */ -} - - -/* -** Signal an error in the call to 'lua_resume', not in the execution -** of the coroutine itself. (Such errors should not be handled by any -** coroutine error handler and should not kill the coroutine.) -*/ -static int resume_error (lua_State *L, const char *msg, int narg) { - L->top -= narg; /* remove args from the stack */ - setsvalue2s(L, L->top, luaS_new(L, msg)); /* push error message */ - api_incr_top(L); - lua_unlock(L); - return LUA_ERRRUN; -} - - -/* -** Do the work for 'lua_resume' in protected mode. Most of the work -** depends on the status of the coroutine: initial state, suspended -** inside a hook, or regularly suspended (optionally with a continuation -** function), plus erroneous cases: non-suspended coroutine or dead -** coroutine. -*/ -static void resume (lua_State *L, void *ud) { - int n = *(cast(int*, ud)); /* number of arguments */ - StkId firstArg = L->top - n; /* first argument */ - CallInfo *ci = L->ci; - if (L->status == LUA_OK) { /* starting a coroutine? */ - if (!luaD_precall(L, firstArg - 1, LUA_MULTRET)) /* Lua function? */ - luaV_execute(L); /* call it */ - } - else { /* resuming from previous yield */ - lua_assert(L->status == LUA_YIELD); - L->status = LUA_OK; /* mark that it is running (again) */ - ci->func = restorestack(L, ci->extra); - if (isLua(ci)) /* yielded inside a hook? */ - luaV_execute(L); /* just continue running Lua code */ - else { /* 'common' yield */ - if (ci->u.c.k != NULL) { /* does it have a continuation function? */ - lua_unlock(L); - n = (*ci->u.c.k)(L, LUA_YIELD, ci->u.c.ctx); /* call continuation */ - lua_lock(L); - api_checknelems(L, n); - firstArg = L->top - n; /* yield results come from continuation */ - } - luaD_poscall(L, ci, firstArg, n); /* finish 'luaD_precall' */ - } - unroll(L, NULL); /* run continuation */ - } -} - - -LUA_API int lua_resume (lua_State *L, lua_State *from, int nargs) { - int status; - unsigned short oldnny = L->nny; /* save "number of non-yieldable" calls */ - lua_lock(L); - if (L->status == LUA_OK) { /* may be starting a coroutine */ - if (L->ci != &L->base_ci) /* not in base level? */ - return resume_error(L, "cannot resume non-suspended coroutine", nargs); - } - else if (L->status != LUA_YIELD) - return resume_error(L, "cannot resume dead coroutine", nargs); - L->nCcalls = (from) ? from->nCcalls + 1 : 1; - if (L->nCcalls >= LUAI_MAXCCALLS) - return resume_error(L, "C stack overflow", nargs); - luai_userstateresume(L, nargs); - L->nny = 0; /* allow yields */ - api_checknelems(L, (L->status == LUA_OK) ? nargs + 1 : nargs); - status = luaD_rawrunprotected(L, resume, &nargs); - if (status == -1) /* error calling 'lua_resume'? */ - status = LUA_ERRRUN; - else { /* continue running after recoverable errors */ - while (errorstatus(status) && recover(L, status)) { - /* unroll continuation */ - status = luaD_rawrunprotected(L, unroll, &status); - } - if (errorstatus(status)) { /* unrecoverable error? */ - L->status = cast_byte(status); /* mark thread as 'dead' */ - seterrorobj(L, status, L->top); /* push error message */ - L->ci->top = L->top; - } - else lua_assert(status == L->status); /* normal end or yield */ - } - L->nny = oldnny; /* restore 'nny' */ - L->nCcalls--; - lua_assert(L->nCcalls == ((from) ? from->nCcalls : 0)); - lua_unlock(L); - return status; -} - - -LUA_API int lua_isyieldable (lua_State *L) { - return (L->nny == 0); -} - - -LUA_API int lua_yieldk (lua_State *L, int nresults, lua_KContext ctx, - lua_KFunction k) { - CallInfo *ci = L->ci; - luai_userstateyield(L, nresults); - lua_lock(L); - api_checknelems(L, nresults); - if (L->nny > 0) { - if (L != G(L)->mainthread) - luaG_runerror(L, "attempt to yield across a C-call boundary"); - else - luaG_runerror(L, "attempt to yield from outside a coroutine"); - } - L->status = LUA_YIELD; - ci->extra = savestack(L, ci->func); /* save current 'func' */ - if (isLua(ci)) { /* inside a hook? */ - api_check(L, k == NULL, "hooks cannot continue after yielding"); - } - else { - if ((ci->u.c.k = k) != NULL) /* is there a continuation? */ - ci->u.c.ctx = ctx; /* save context */ - ci->func = L->top - nresults - 1; /* protect stack below results */ - luaD_throw(L, LUA_YIELD); - } - lua_assert(ci->callstatus & CIST_HOOKED); /* must be inside a hook */ - lua_unlock(L); - return 0; /* return to 'luaD_hook' */ -} - - -int luaD_pcall (lua_State *L, Pfunc func, void *u, - ptrdiff_t old_top, ptrdiff_t ef) { - int status; - CallInfo *old_ci = L->ci; - lu_byte old_allowhooks = L->allowhook; - unsigned short old_nny = L->nny; - ptrdiff_t old_errfunc = L->errfunc; - L->errfunc = ef; - status = luaD_rawrunprotected(L, func, u); - if (status != LUA_OK) { /* an error occurred? */ - StkId oldtop = restorestack(L, old_top); - luaF_close(L, oldtop); /* close possible pending closures */ - seterrorobj(L, status, oldtop); - L->ci = old_ci; - L->allowhook = old_allowhooks; - L->nny = old_nny; - luaD_shrinkstack(L); - } - L->errfunc = old_errfunc; - return status; -} - - - -/* -** Execute a protected parser. -*/ -struct SParser { /* data to 'f_parser' */ - ZIO *z; - Mbuffer buff; /* dynamic structure used by the scanner */ - Dyndata dyd; /* dynamic structures used by the parser */ - const char *mode; - const char *name; -}; - - -static void checkmode (lua_State *L, const char *mode, const char *x) { - if (mode && strchr(mode, x[0]) == NULL) { - luaO_pushfstring(L, - "attempt to load a %s chunk (mode is '%s')", x, mode); - luaD_throw(L, LUA_ERRSYNTAX); - } -} - - -static void f_parser (lua_State *L, void *ud) { - LClosure *cl; - struct SParser *p = cast(struct SParser *, ud); - int c = zgetc(p->z); /* read first character */ - if (c == LUA_SIGNATURE[0]) { - checkmode(L, p->mode, "binary"); - cl = luaU_undump(L, p->z, p->name); - } - else { - checkmode(L, p->mode, "text"); - cl = luaY_parser(L, p->z, &p->buff, &p->dyd, p->name, c); - } - lua_assert(cl->nupvalues == cl->p->sizeupvalues); - luaF_initupvals(L, cl); -} - - -int luaD_protectedparser (lua_State *L, ZIO *z, const char *name, - const char *mode) { - struct SParser p; - int status; - L->nny++; /* cannot yield during parsing */ - p.z = z; p.name = name; p.mode = mode; - p.dyd.actvar.arr = NULL; p.dyd.actvar.size = 0; - p.dyd.gt.arr = NULL; p.dyd.gt.size = 0; - p.dyd.label.arr = NULL; p.dyd.label.size = 0; - luaZ_initbuffer(L, &p.buff); - status = luaD_pcall(L, f_parser, &p, savestack(L, L->top), L->errfunc); - luaZ_freebuffer(L, &p.buff); - luaM_freearray(L, p.dyd.actvar.arr, p.dyd.actvar.size); - luaM_freearray(L, p.dyd.gt.arr, p.dyd.gt.size); - luaM_freearray(L, p.dyd.label.arr, p.dyd.label.size); - L->nny--; - return status; -} - - |