diff options
Diffstat (limited to 'lua-5.1.4/src/ldo.c')
-rw-r--r-- | lua-5.1.4/src/ldo.c | 518 |
1 files changed, 0 insertions, 518 deletions
diff --git a/lua-5.1.4/src/ldo.c b/lua-5.1.4/src/ldo.c deleted file mode 100644 index 8de05f728..000000000 --- a/lua-5.1.4/src/ldo.c +++ /dev/null @@ -1,518 +0,0 @@ -/* -** $Id: ldo.c,v 2.38.1.3 2008/01/18 22:31:22 roberto Exp $ -** Stack and Call structure of Lua -** See Copyright Notice in lua.h -*/ - - -#include <setjmp.h> -#include <stdlib.h> -#include <string.h> - -#define ldo_c -#define LUA_CORE - -#include "lua.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" - - - - -/* -** {====================================================== -** Error-recovery functions -** ======================================================= -*/ - - -/* chain list of long jump buffers */ -struct lua_longjmp { - struct lua_longjmp *previous; - luai_jmpbuf b; - volatile int status; /* error code */ -}; - - -void luaD_seterrorobj (lua_State *L, int errcode, StkId oldtop) { - switch (errcode) { - case LUA_ERRMEM: { - setsvalue2s(L, oldtop, luaS_newliteral(L, MEMERRMSG)); - break; - } - case LUA_ERRERR: { - setsvalue2s(L, oldtop, luaS_newliteral(L, "error in error handling")); - break; - } - case LUA_ERRSYNTAX: - case LUA_ERRRUN: { - setobjs2s(L, oldtop, L->top - 1); /* error message on current top */ - break; - } - } - L->top = oldtop + 1; -} - - -static void restore_stack_limit (lua_State *L) { - lua_assert(L->stack_last - L->stack == L->stacksize - EXTRA_STACK - 1); - if (L->size_ci > LUAI_MAXCALLS) { /* there was an overflow? */ - int inuse = cast_int(L->ci - L->base_ci); - if (inuse + 1 < LUAI_MAXCALLS) /* can `undo' overflow? */ - luaD_reallocCI(L, LUAI_MAXCALLS); - } -} - - -static void resetstack (lua_State *L, int status) { - L->ci = L->base_ci; - L->base = L->ci->base; - luaF_close(L, L->base); /* close eventual pending closures */ - luaD_seterrorobj(L, status, L->base); - L->nCcalls = L->baseCcalls; - L->allowhook = 1; - restore_stack_limit(L); - L->errfunc = 0; - L->errorJmp = NULL; -} - - -void luaD_throw (lua_State *L, int errcode) { - if (L->errorJmp) { - L->errorJmp->status = errcode; - LUAI_THROW(L, L->errorJmp); - } - else { - L->status = cast_byte(errcode); - if (G(L)->panic) { - resetstack(L, errcode); - lua_unlock(L); - G(L)->panic(L); - } - exit(EXIT_FAILURE); - } -} - - -int luaD_rawrunprotected (lua_State *L, Pfunc f, void *ud) { - struct lua_longjmp lj; - lj.status = 0; - 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 */ - return lj.status; -} - -/* }====================================================== */ - - -static void correctstack (lua_State *L, TValue *oldstack) { - CallInfo *ci; - GCObject *up; - L->top = (L->top - oldstack) + L->stack; - for (up = L->openupval; up != NULL; up = up->gch.next) - gco2uv(up)->v = (gco2uv(up)->v - oldstack) + L->stack; - for (ci = L->base_ci; ci <= L->ci; ci++) { - ci->top = (ci->top - oldstack) + L->stack; - ci->base = (ci->base - oldstack) + L->stack; - ci->func = (ci->func - oldstack) + L->stack; - } - L->base = (L->base - oldstack) + L->stack; -} - - -void luaD_reallocstack (lua_State *L, int newsize) { - TValue *oldstack = L->stack; - int realsize = newsize + 1 + EXTRA_STACK; - lua_assert(L->stack_last - L->stack == L->stacksize - EXTRA_STACK - 1); - luaM_reallocvector(L, L->stack, L->stacksize, realsize, TValue); - L->stacksize = realsize; - L->stack_last = L->stack+newsize; - correctstack(L, oldstack); -} - - -void luaD_reallocCI (lua_State *L, int newsize) { - CallInfo *oldci = L->base_ci; - luaM_reallocvector(L, L->base_ci, L->size_ci, newsize, CallInfo); - L->size_ci = newsize; - L->ci = (L->ci - oldci) + L->base_ci; - L->end_ci = L->base_ci + L->size_ci - 1; -} - - -void luaD_growstack (lua_State *L, int n) { - if (n <= L->stacksize) /* double size is enough? */ - luaD_reallocstack(L, 2*L->stacksize); - else - luaD_reallocstack(L, L->stacksize + n); -} - - -static CallInfo *growCI (lua_State *L) { - if (L->size_ci > LUAI_MAXCALLS) /* overflow while handling overflow? */ - luaD_throw(L, LUA_ERRERR); - else { - luaD_reallocCI(L, 2*L->size_ci); - if (L->size_ci > LUAI_MAXCALLS) - luaG_runerror(L, "stack overflow"); - } - return ++L->ci; -} - - -void luaD_callhook (lua_State *L, int event, int line) { - lua_Hook hook = L->hook; - if (hook && L->allowhook) { - ptrdiff_t top = savestack(L, L->top); - ptrdiff_t ci_top = savestack(L, L->ci->top); - lua_Debug ar; - ar.event = event; - ar.currentline = line; - if (event == LUA_HOOKTAILRET) - ar.i_ci = 0; /* tail call; no debug information about it */ - else - ar.i_ci = cast_int(L->ci - L->base_ci); - luaD_checkstack(L, LUA_MINSTACK); /* ensure minimum stack size */ - L->ci->top = L->top + LUA_MINSTACK; - lua_assert(L->ci->top <= L->stack_last); - L->allowhook = 0; /* cannot call hooks inside a hook */ - lua_unlock(L); - (*hook)(L, &ar); - lua_lock(L); - lua_assert(!L->allowhook); - L->allowhook = 1; - L->ci->top = restorestack(L, ci_top); - L->top = restorestack(L, top); - } -} - - -static StkId adjust_varargs (lua_State *L, Proto *p, int actual) { - int i; - int nfixargs = p->numparams; - Table *htab = NULL; - StkId base, fixed; - for (; actual < nfixargs; ++actual) - setnilvalue(L->top++); -#if defined(LUA_COMPAT_VARARG) - if (p->is_vararg & VARARG_NEEDSARG) { /* compat. with old-style vararg? */ - int nvar = actual - nfixargs; /* number of extra arguments */ - lua_assert(p->is_vararg & VARARG_HASARG); - luaC_checkGC(L); - htab = luaH_new(L, nvar, 1); /* create `arg' table */ - for (i=0; i<nvar; i++) /* put extra arguments into `arg' table */ - setobj2n(L, luaH_setnum(L, htab, i+1), L->top - nvar + i); - /* store counter in field `n' */ - setnvalue(luaH_setstr(L, htab, luaS_newliteral(L, "n")), cast_num(nvar)); - } -#endif - /* 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++) { - setobjs2s(L, L->top++, fixed+i); - setnilvalue(fixed+i); - } - /* add `arg' parameter */ - if (htab) { - sethvalue(L, L->top++, htab); - lua_assert(iswhite(obj2gco(htab))); - } - return base; -} - - -static StkId tryfuncTM (lua_State *L, StkId func) { - const TValue *tm = luaT_gettmbyobj(L, func, TM_CALL); - StkId p; - ptrdiff_t funcr = savestack(L, func); - 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); - incr_top(L); - func = restorestack(L, funcr); /* previous call may change stack */ - setobj2s(L, func, tm); /* tag method is the new function to be called */ - return func; -} - - - -#define inc_ci(L) \ - ((L->ci == L->end_ci) ? growCI(L) : \ - (condhardstacktests(luaD_reallocCI(L, L->size_ci)), ++L->ci)) - - -int luaD_precall (lua_State *L, StkId func, int nresults) { - LClosure *cl; - ptrdiff_t funcr; - if (!ttisfunction(func)) /* `func' is not a function? */ - func = tryfuncTM(L, func); /* check the `function' tag method */ - funcr = savestack(L, func); - cl = &clvalue(func)->l; - L->ci->savedpc = L->savedpc; - if (!cl->isC) { /* Lua function? prepare its call */ - CallInfo *ci; - StkId st, base; - Proto *p = cl->p; - luaD_checkstack(L, p->maxstacksize); - func = restorestack(L, funcr); - if (!p->is_vararg) { /* no varargs? */ - base = func + 1; - if (L->top > base + p->numparams) - L->top = base + p->numparams; - } - else { /* vararg function */ - int nargs = cast_int(L->top - func) - 1; - base = adjust_varargs(L, p, nargs); - func = restorestack(L, funcr); /* previous call may change the stack */ - } - ci = inc_ci(L); /* now `enter' new function */ - ci->func = func; - L->base = ci->base = base; - ci->top = L->base + p->maxstacksize; - lua_assert(ci->top <= L->stack_last); - L->savedpc = p->code; /* starting point */ - ci->tailcalls = 0; - ci->nresults = nresults; - for (st = L->top; st < ci->top; st++) - setnilvalue(st); - L->top = ci->top; - if (L->hookmask & LUA_MASKCALL) { - L->savedpc++; /* hooks assume 'pc' is already incremented */ - luaD_callhook(L, LUA_HOOKCALL, -1); - L->savedpc--; /* correct 'pc' */ - } - return PCRLUA; - } - else { /* if is a C function, call it */ - CallInfo *ci; - int n; - luaD_checkstack(L, LUA_MINSTACK); /* ensure minimum stack size */ - ci = inc_ci(L); /* now `enter' new function */ - ci->func = restorestack(L, funcr); - L->base = ci->base = ci->func + 1; - ci->top = L->top + LUA_MINSTACK; - lua_assert(ci->top <= L->stack_last); - ci->nresults = nresults; - if (L->hookmask & LUA_MASKCALL) - luaD_callhook(L, LUA_HOOKCALL, -1); - lua_unlock(L); - n = (*curr_func(L)->c.f)(L); /* do the actual call */ - lua_lock(L); - if (n < 0) /* yielding? */ - return PCRYIELD; - else { - luaD_poscall(L, L->top - n); - return PCRC; - } - } -} - - -static StkId callrethooks (lua_State *L, StkId firstResult) { - ptrdiff_t fr = savestack(L, firstResult); /* next call may change stack */ - luaD_callhook(L, LUA_HOOKRET, -1); - if (f_isLua(L->ci)) { /* Lua function? */ - while ((L->hookmask & LUA_MASKRET) && L->ci->tailcalls--) /* tail calls */ - luaD_callhook(L, LUA_HOOKTAILRET, -1); - } - return restorestack(L, fr); -} - - -int luaD_poscall (lua_State *L, StkId firstResult) { - StkId res; - int wanted, i; - CallInfo *ci; - if (L->hookmask & LUA_MASKRET) - firstResult = callrethooks(L, firstResult); - ci = L->ci--; - res = ci->func; /* res == final position of 1st result */ - wanted = ci->nresults; - L->base = (ci - 1)->base; /* restore base */ - L->savedpc = (ci - 1)->savedpc; /* restore savedpc */ - /* move results to correct place */ - for (i = wanted; i != 0 && firstResult < L->top; i--) - setobjs2s(L, res++, firstResult++); - while (i-- > 0) - setnilvalue(res++); - L->top = res; - return (wanted - LUA_MULTRET); /* 0 iff wanted == LUA_MULTRET */ -} - - -/* -** 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) { - 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 */ - } - if (luaD_precall(L, func, nResults) == PCRLUA) /* is a Lua function? */ - luaV_execute(L, 1); /* call it */ - L->nCcalls--; - luaC_checkGC(L); -} - - -static void resume (lua_State *L, void *ud) { - StkId firstArg = cast(StkId, ud); - CallInfo *ci = L->ci; - if (L->status == 0) { /* start coroutine? */ - lua_assert(ci == L->base_ci && firstArg > L->base); - if (luaD_precall(L, firstArg - 1, LUA_MULTRET) != PCRLUA) - return; - } - else { /* resuming from previous yield */ - lua_assert(L->status == LUA_YIELD); - L->status = 0; - if (!f_isLua(ci)) { /* `common' yield? */ - /* finish interrupted execution of `OP_CALL' */ - lua_assert(GET_OPCODE(*((ci-1)->savedpc - 1)) == OP_CALL || - GET_OPCODE(*((ci-1)->savedpc - 1)) == OP_TAILCALL); - if (luaD_poscall(L, firstArg)) /* complete it... */ - L->top = L->ci->top; /* and correct top if not multiple results */ - } - else /* yielded inside a hook: just continue its execution */ - L->base = L->ci->base; - } - luaV_execute(L, cast_int(L->ci - L->base_ci)); -} - - -static int resume_error (lua_State *L, const char *msg) { - L->top = L->ci->base; - setsvalue2s(L, L->top, luaS_new(L, msg)); - incr_top(L); - lua_unlock(L); - return LUA_ERRRUN; -} - - -LUA_API int lua_resume (lua_State *L, int nargs) { - int status; - lua_lock(L); - if (L->status != LUA_YIELD && (L->status != 0 || L->ci != L->base_ci)) - return resume_error(L, "cannot resume non-suspended coroutine"); - if (L->nCcalls >= LUAI_MAXCCALLS) - return resume_error(L, "C stack overflow"); - luai_userstateresume(L, nargs); - lua_assert(L->errfunc == 0); - L->baseCcalls = ++L->nCcalls; - status = luaD_rawrunprotected(L, resume, L->top - nargs); - if (status != 0) { /* error? */ - L->status = cast_byte(status); /* mark thread as `dead' */ - luaD_seterrorobj(L, status, L->top); - L->ci->top = L->top; - } - else { - lua_assert(L->nCcalls == L->baseCcalls); - status = L->status; - } - --L->nCcalls; - lua_unlock(L); - return status; -} - - -LUA_API int lua_yield (lua_State *L, int nresults) { - luai_userstateyield(L, nresults); - lua_lock(L); - if (L->nCcalls > L->baseCcalls) - luaG_runerror(L, "attempt to yield across metamethod/C-call boundary"); - L->base = L->top - nresults; /* protect stack slots below */ - L->status = LUA_YIELD; - lua_unlock(L); - return -1; -} - - -int luaD_pcall (lua_State *L, Pfunc func, void *u, - ptrdiff_t old_top, ptrdiff_t ef) { - int status; - unsigned short oldnCcalls = L->nCcalls; - ptrdiff_t old_ci = saveci(L, L->ci); - lu_byte old_allowhooks = L->allowhook; - ptrdiff_t old_errfunc = L->errfunc; - L->errfunc = ef; - status = luaD_rawrunprotected(L, func, u); - if (status != 0) { /* an error occurred? */ - StkId oldtop = restorestack(L, old_top); - luaF_close(L, oldtop); /* close eventual pending closures */ - luaD_seterrorobj(L, status, oldtop); - L->nCcalls = oldnCcalls; - L->ci = restoreci(L, old_ci); - L->base = L->ci->base; - L->savedpc = L->ci->savedpc; - L->allowhook = old_allowhooks; - restore_stack_limit(L); - } - L->errfunc = old_errfunc; - return status; -} - - - -/* -** Execute a protected parser. -*/ -struct SParser { /* data to `f_parser' */ - ZIO *z; - Mbuffer buff; /* buffer to be used by the scanner */ - const char *name; -}; - -static void f_parser (lua_State *L, void *ud) { - int i; - Proto *tf; - Closure *cl; - struct SParser *p = cast(struct SParser *, ud); - int c = luaZ_lookahead(p->z); - luaC_checkGC(L); - tf = ((c == LUA_SIGNATURE[0]) ? luaU_undump : luaY_parser)(L, p->z, - &p->buff, p->name); - cl = luaF_newLclosure(L, tf->nups, hvalue(gt(L))); - cl->l.p = tf; - for (i = 0; i < tf->nups; i++) /* initialize eventual upvalues */ - cl->l.upvals[i] = luaF_newupval(L); - setclvalue(L, L->top, cl); - incr_top(L); -} - - -int luaD_protectedparser (lua_State *L, ZIO *z, const char *name) { - struct SParser p; - int status; - p.z = z; p.name = name; - luaZ_initbuffer(L, &p.buff); - status = luaD_pcall(L, f_parser, &p, savestack(L, L->top), L->errfunc); - luaZ_freebuffer(L, &p.buff); - return status; -} - - |