Aegisub/contrib/lua51/src/lapi.c
Amar Takhar 391219ea54 SVN Transition Step 5/7
1. svn mv assdraw csri hunspell lua51 contrib

* See r2749 for full description.

Originally committed to SVN as r2754.
2009-03-08 08:31:41 +00:00

1080 lines
22 KiB
C

/*
** $Id: lapi.c,v 2.55 2006/06/07 12:37:17 roberto Exp $
** Lua API
** See Copyright Notice in lua.h
*/
#include <assert.h>
#include <math.h>
#include <stdarg.h>
#include <string.h>
#define lapi_c
#define LUA_CORE
#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 "lstate.h"
#include "lstring.h"
#include "ltable.h"
#include "ltm.h"
#include "lundump.h"
#include "lvm.h"
const char lua_ident[] =
"$Lua: " LUA_RELEASE " " LUA_COPYRIGHT " $\n"
"$Authors: " LUA_AUTHORS " $\n"
"$URL: www.lua.org $\n";
#define api_checknelems(L, n) api_check(L, (n) <= (L->top - L->base))
#define api_checkvalidindex(L, i) api_check(L, (i) != luaO_nilobject)
#define api_incr_top(L) {api_check(L, L->top < L->ci->top); L->top++;}
static TValue *index2adr (lua_State *L, int idx) {
if (idx > 0) {
TValue *o = L->base + (idx - 1);
api_check(L, idx <= L->ci->top - L->base);
if (o >= L->top) return cast(TValue *, luaO_nilobject);
else return o;
}
else if (idx > LUA_REGISTRYINDEX) {
api_check(L, idx != 0 && -idx <= L->top - L->base);
return L->top + idx;
}
else switch (idx) { /* pseudo-indices */
case LUA_REGISTRYINDEX: return registry(L);
case LUA_ENVIRONINDEX: {
Closure *func = curr_func(L);
sethvalue(L, &L->env, func->c.env);
return &L->env;
}
case LUA_GLOBALSINDEX: return gt(L);
default: {
Closure *func = curr_func(L);
idx = LUA_GLOBALSINDEX - idx;
return (idx <= func->c.nupvalues)
? &func->c.upvalue[idx-1]
: cast(TValue *, luaO_nilobject);
}
}
}
static Table *getcurrenv (lua_State *L) {
if (L->ci == L->base_ci) /* no enclosing function? */
return hvalue(gt(L)); /* use global table as environment */
else {
Closure *func = curr_func(L);
return func->c.env;
}
}
void luaA_pushobject (lua_State *L, const TValue *o) {
setobj2s(L, L->top, o);
api_incr_top(L);
}
LUA_API int lua_checkstack (lua_State *L, int size) {
int res;
lua_lock(L);
if ((L->top - L->base + size) > LUAI_MAXCSTACK)
res = 0; /* stack overflow */
else {
luaD_checkstack(L, size);
if (L->ci->top < L->top + size)
L->ci->top = L->top + size;
res = 1;
}
lua_unlock(L);
return res;
}
LUA_API void lua_xmove (lua_State *from, lua_State *to, int n) {
int i;
if (from == to) return;
lua_lock(to);
api_checknelems(from, n);
api_check(from, G(from) == G(to));
api_check(from, to->ci->top - to->top >= n);
from->top -= n;
for (i = 0; i < n; i++) {
setobj2s(to, to->top++, from->top + i);
}
lua_unlock(to);
}
LUA_API lua_CFunction lua_atpanic (lua_State *L, lua_CFunction panicf) {
lua_CFunction old;
lua_lock(L);
old = G(L)->panic;
G(L)->panic = panicf;
lua_unlock(L);
return old;
}
LUA_API lua_State *lua_newthread (lua_State *L) {
lua_State *L1;
lua_lock(L);
luaC_checkGC(L);
L1 = luaE_newthread(L);
setthvalue(L, L->top, L1);
api_incr_top(L);
lua_unlock(L);
luai_userstatethread(L, L1);
return L1;
}
/*
** basic stack manipulation
*/
LUA_API int lua_gettop (lua_State *L) {
return cast_int(L->top - L->base);
}
LUA_API void lua_settop (lua_State *L, int idx) {
lua_lock(L);
if (idx >= 0) {
api_check(L, idx <= L->stack_last - L->base);
while (L->top < L->base + idx)
setnilvalue(L->top++);
L->top = L->base + idx;
}
else {
api_check(L, -(idx+1) <= (L->top - L->base));
L->top += idx+1; /* `subtract' index (index is negative) */
}
lua_unlock(L);
}
LUA_API void lua_remove (lua_State *L, int idx) {
StkId p;
lua_lock(L);
p = index2adr(L, idx);
api_checkvalidindex(L, p);
while (++p < L->top) setobjs2s(L, p-1, p);
L->top--;
lua_unlock(L);
}
LUA_API void lua_insert (lua_State *L, int idx) {
StkId p;
StkId q;
lua_lock(L);
p = index2adr(L, idx);
api_checkvalidindex(L, p);
for (q = L->top; q>p; q--) setobjs2s(L, q, q-1);
setobjs2s(L, p, L->top);
lua_unlock(L);
}
LUA_API void lua_replace (lua_State *L, int idx) {
StkId o;
lua_lock(L);
/* explicit test for incompatible code */
if (idx == LUA_ENVIRONINDEX && L->ci == L->base_ci)
luaG_runerror(L, "no calling environment");
api_checknelems(L, 1);
o = index2adr(L, idx);
api_checkvalidindex(L, o);
if (idx == LUA_ENVIRONINDEX) {
Closure *func = curr_func(L);
api_check(L, ttistable(L->top - 1));
func->c.env = hvalue(L->top - 1);
luaC_barrier(L, func, L->top - 1);
}
else {
setobj(L, o, L->top - 1);
if (idx < LUA_GLOBALSINDEX) /* function upvalue? */
luaC_barrier(L, curr_func(L), L->top - 1);
}
L->top--;
lua_unlock(L);
}
LUA_API void lua_pushvalue (lua_State *L, int idx) {
lua_lock(L);
setobj2s(L, L->top, index2adr(L, idx));
api_incr_top(L);
lua_unlock(L);
}
/*
** access functions (stack -> C)
*/
LUA_API int lua_type (lua_State *L, int idx) {
StkId o = index2adr(L, idx);
return (o == luaO_nilobject) ? LUA_TNONE : ttype(o);
}
LUA_API const char *lua_typename (lua_State *L, int t) {
UNUSED(L);
return (t == LUA_TNONE) ? "no value" : luaT_typenames[t];
}
LUA_API int lua_iscfunction (lua_State *L, int idx) {
StkId o = index2adr(L, idx);
return iscfunction(o);
}
LUA_API int lua_isnumber (lua_State *L, int idx) {
TValue n;
const TValue *o = index2adr(L, idx);
return tonumber(o, &n);
}
LUA_API int lua_isstring (lua_State *L, int idx) {
int t = lua_type(L, idx);
return (t == LUA_TSTRING || t == LUA_TNUMBER);
}
LUA_API int lua_isuserdata (lua_State *L, int idx) {
const TValue *o = index2adr(L, idx);
return (ttisuserdata(o) || ttislightuserdata(o));
}
LUA_API int lua_rawequal (lua_State *L, int index1, int index2) {
StkId o1 = index2adr(L, index1);
StkId o2 = index2adr(L, index2);
return (o1 == luaO_nilobject || o2 == luaO_nilobject) ? 0
: luaO_rawequalObj(o1, o2);
}
LUA_API int lua_equal (lua_State *L, int index1, int index2) {
StkId o1, o2;
int i;
lua_lock(L); /* may call tag method */
o1 = index2adr(L, index1);
o2 = index2adr(L, index2);
i = (o1 == luaO_nilobject || o2 == luaO_nilobject) ? 0 : equalobj(L, o1, o2);
lua_unlock(L);
return i;
}
LUA_API int lua_lessthan (lua_State *L, int index1, int index2) {
StkId o1, o2;
int i;
lua_lock(L); /* may call tag method */
o1 = index2adr(L, index1);
o2 = index2adr(L, index2);
i = (o1 == luaO_nilobject || o2 == luaO_nilobject) ? 0
: luaV_lessthan(L, o1, o2);
lua_unlock(L);
return i;
}
LUA_API lua_Number lua_tonumber (lua_State *L, int idx) {
TValue n;
const TValue *o = index2adr(L, idx);
if (tonumber(o, &n))
return nvalue(o);
else
return 0;
}
LUA_API lua_Integer lua_tointeger (lua_State *L, int idx) {
TValue n;
const TValue *o = index2adr(L, idx);
if (tonumber(o, &n)) {
lua_Integer res;
lua_Number num = nvalue(o);
lua_number2integer(res, num);
return res;
}
else
return 0;
}
LUA_API int lua_toboolean (lua_State *L, int idx) {
const TValue *o = index2adr(L, idx);
return !l_isfalse(o);
}
LUA_API const char *lua_tolstring (lua_State *L, int idx, size_t *len) {
StkId o = index2adr(L, idx);
if (!ttisstring(o)) {
lua_lock(L); /* `luaV_tostring' may create a new string */
if (!luaV_tostring(L, o)) { /* conversion failed? */
if (len != NULL) *len = 0;
lua_unlock(L);
return NULL;
}
luaC_checkGC(L);
o = index2adr(L, idx); /* previous call may reallocate the stack */
lua_unlock(L);
}
if (len != NULL) *len = tsvalue(o)->len;
return svalue(o);
}
LUA_API size_t lua_objlen (lua_State *L, int idx) {
StkId o = index2adr(L, idx);
switch (ttype(o)) {
case LUA_TSTRING: return tsvalue(o)->len;
case LUA_TUSERDATA: return uvalue(o)->len;
case LUA_TTABLE: return luaH_getn(hvalue(o));
case LUA_TNUMBER: {
size_t l;
lua_lock(L); /* `luaV_tostring' may create a new string */
l = (luaV_tostring(L, o) ? tsvalue(o)->len : 0);
lua_unlock(L);
return l;
}
default: return 0;
}
}
LUA_API lua_CFunction lua_tocfunction (lua_State *L, int idx) {
StkId o = index2adr(L, idx);
return (!iscfunction(o)) ? NULL : clvalue(o)->c.f;
}
LUA_API void *lua_touserdata (lua_State *L, int idx) {
StkId o = index2adr(L, idx);
switch (ttype(o)) {
case LUA_TUSERDATA: return (rawuvalue(o) + 1);
case LUA_TLIGHTUSERDATA: return pvalue(o);
default: return NULL;
}
}
LUA_API lua_State *lua_tothread (lua_State *L, int idx) {
StkId o = index2adr(L, idx);
return (!ttisthread(o)) ? NULL : thvalue(o);
}
LUA_API const void *lua_topointer (lua_State *L, int idx) {
StkId o = index2adr(L, idx);
switch (ttype(o)) {
case LUA_TTABLE: return hvalue(o);
case LUA_TFUNCTION: return clvalue(o);
case LUA_TTHREAD: return thvalue(o);
case LUA_TUSERDATA:
case LUA_TLIGHTUSERDATA:
return lua_touserdata(L, idx);
default: return NULL;
}
}
/*
** push functions (C -> stack)
*/
LUA_API void lua_pushnil (lua_State *L) {
lua_lock(L);
setnilvalue(L->top);
api_incr_top(L);
lua_unlock(L);
}
LUA_API void lua_pushnumber (lua_State *L, lua_Number n) {
lua_lock(L);
setnvalue(L->top, n);
api_incr_top(L);
lua_unlock(L);
}
LUA_API void lua_pushinteger (lua_State *L, lua_Integer n) {
lua_lock(L);
setnvalue(L->top, cast_num(n));
api_incr_top(L);
lua_unlock(L);
}
LUA_API void lua_pushlstring (lua_State *L, const char *s, size_t len) {
lua_lock(L);
luaC_checkGC(L);
setsvalue2s(L, L->top, luaS_newlstr(L, s, len));
api_incr_top(L);
lua_unlock(L);
}
LUA_API void lua_pushstring (lua_State *L, const char *s) {
if (s == NULL)
lua_pushnil(L);
else
lua_pushlstring(L, s, strlen(s));
}
LUA_API const char *lua_pushvfstring (lua_State *L, const char *fmt,
va_list argp) {
const char *ret;
lua_lock(L);
luaC_checkGC(L);
ret = luaO_pushvfstring(L, fmt, argp);
lua_unlock(L);
return ret;
}
LUA_API const char *lua_pushfstring (lua_State *L, const char *fmt, ...) {
const char *ret;
va_list argp;
lua_lock(L);
luaC_checkGC(L);
va_start(argp, fmt);
ret = luaO_pushvfstring(L, fmt, argp);
va_end(argp);
lua_unlock(L);
return ret;
}
LUA_API void lua_pushcclosure (lua_State *L, lua_CFunction fn, int n) {
Closure *cl;
lua_lock(L);
luaC_checkGC(L);
api_checknelems(L, n);
cl = luaF_newCclosure(L, n, getcurrenv(L));
cl->c.f = fn;
L->top -= n;
while (n--)
setobj2n(L, &cl->c.upvalue[n], L->top+n);
setclvalue(L, L->top, cl);
lua_assert(iswhite(obj2gco(cl)));
api_incr_top(L);
lua_unlock(L);
}
LUA_API void lua_pushboolean (lua_State *L, int b) {
lua_lock(L);
setbvalue(L->top, (b != 0)); /* ensure that true is 1 */
api_incr_top(L);
lua_unlock(L);
}
LUA_API void lua_pushlightuserdata (lua_State *L, void *p) {
lua_lock(L);
setpvalue(L->top, p);
api_incr_top(L);
lua_unlock(L);
}
LUA_API int lua_pushthread (lua_State *L) {
lua_lock(L);
setthvalue(L, L->top, L);
api_incr_top(L);
lua_unlock(L);
return (G(L)->mainthread == L);
}
/*
** get functions (Lua -> stack)
*/
LUA_API void lua_gettable (lua_State *L, int idx) {
StkId t;
lua_lock(L);
t = index2adr(L, idx);
api_checkvalidindex(L, t);
luaV_gettable(L, t, L->top - 1, L->top - 1);
lua_unlock(L);
}
LUA_API void lua_getfield (lua_State *L, int idx, const char *k) {
StkId t;
TValue key;
lua_lock(L);
t = index2adr(L, idx);
api_checkvalidindex(L, t);
setsvalue(L, &key, luaS_new(L, k));
luaV_gettable(L, t, &key, L->top);
api_incr_top(L);
lua_unlock(L);
}
LUA_API void lua_rawget (lua_State *L, int idx) {
StkId t;
lua_lock(L);
t = index2adr(L, idx);
api_check(L, ttistable(t));
setobj2s(L, L->top - 1, luaH_get(hvalue(t), L->top - 1));
lua_unlock(L);
}
LUA_API void lua_rawgeti (lua_State *L, int idx, int n) {
StkId o;
lua_lock(L);
o = index2adr(L, idx);
api_check(L, ttistable(o));
setobj2s(L, L->top, luaH_getnum(hvalue(o), n));
api_incr_top(L);
lua_unlock(L);
}
LUA_API void lua_createtable (lua_State *L, int narray, int nrec) {
lua_lock(L);
luaC_checkGC(L);
sethvalue(L, L->top, luaH_new(L, narray, nrec));
api_incr_top(L);
lua_unlock(L);
}
LUA_API int lua_getmetatable (lua_State *L, int objindex) {
const TValue *obj;
Table *mt = NULL;
int res;
lua_lock(L);
obj = index2adr(L, objindex);
switch (ttype(obj)) {
case LUA_TTABLE:
mt = hvalue(obj)->metatable;
break;
case LUA_TUSERDATA:
mt = uvalue(obj)->metatable;
break;
default:
mt = G(L)->mt[ttype(obj)];
break;
}
if (mt == NULL)
res = 0;
else {
sethvalue(L, L->top, mt);
api_incr_top(L);
res = 1;
}
lua_unlock(L);
return res;
}
LUA_API void lua_getfenv (lua_State *L, int idx) {
StkId o;
lua_lock(L);
o = index2adr(L, idx);
api_checkvalidindex(L, o);
switch (ttype(o)) {
case LUA_TFUNCTION:
sethvalue(L, L->top, clvalue(o)->c.env);
break;
case LUA_TUSERDATA:
sethvalue(L, L->top, uvalue(o)->env);
break;
case LUA_TTHREAD:
setobj2s(L, L->top, gt(thvalue(o)));
break;
default:
setnilvalue(L->top);
break;
}
api_incr_top(L);
lua_unlock(L);
}
/*
** set functions (stack -> Lua)
*/
LUA_API void lua_settable (lua_State *L, int idx) {
StkId t;
lua_lock(L);
api_checknelems(L, 2);
t = index2adr(L, idx);
api_checkvalidindex(L, t);
luaV_settable(L, t, L->top - 2, L->top - 1);
L->top -= 2; /* pop index and value */
lua_unlock(L);
}
LUA_API void lua_setfield (lua_State *L, int idx, const char *k) {
StkId t;
TValue key;
lua_lock(L);
api_checknelems(L, 1);
t = index2adr(L, idx);
api_checkvalidindex(L, t);
setsvalue(L, &key, luaS_new(L, k));
luaV_settable(L, t, &key, L->top - 1);
L->top--; /* pop value */
lua_unlock(L);
}
LUA_API void lua_rawset (lua_State *L, int idx) {
StkId t;
lua_lock(L);
api_checknelems(L, 2);
t = index2adr(L, idx);
api_check(L, ttistable(t));
setobj2t(L, luaH_set(L, hvalue(t), L->top-2), L->top-1);
luaC_barriert(L, hvalue(t), L->top-1);
L->top -= 2;
lua_unlock(L);
}
LUA_API void lua_rawseti (lua_State *L, int idx, int n) {
StkId o;
lua_lock(L);
api_checknelems(L, 1);
o = index2adr(L, idx);
api_check(L, ttistable(o));
setobj2t(L, luaH_setnum(L, hvalue(o), n), L->top-1);
luaC_barriert(L, hvalue(o), L->top-1);
L->top--;
lua_unlock(L);
}
LUA_API int lua_setmetatable (lua_State *L, int objindex) {
TValue *obj;
Table *mt;
lua_lock(L);
api_checknelems(L, 1);
obj = index2adr(L, objindex);
api_checkvalidindex(L, obj);
if (ttisnil(L->top - 1))
mt = NULL;
else {
api_check(L, ttistable(L->top - 1));
mt = hvalue(L->top - 1);
}
switch (ttype(obj)) {
case LUA_TTABLE: {
hvalue(obj)->metatable = mt;
if (mt)
luaC_objbarriert(L, hvalue(obj), mt);
break;
}
case LUA_TUSERDATA: {
uvalue(obj)->metatable = mt;
if (mt)
luaC_objbarrier(L, rawuvalue(obj), mt);
break;
}
default: {
G(L)->mt[ttype(obj)] = mt;
break;
}
}
L->top--;
lua_unlock(L);
return 1;
}
LUA_API int lua_setfenv (lua_State *L, int idx) {
StkId o;
int res = 1;
lua_lock(L);
api_checknelems(L, 1);
o = index2adr(L, idx);
api_checkvalidindex(L, o);
api_check(L, ttistable(L->top - 1));
switch (ttype(o)) {
case LUA_TFUNCTION:
clvalue(o)->c.env = hvalue(L->top - 1);
break;
case LUA_TUSERDATA:
uvalue(o)->env = hvalue(L->top - 1);
break;
case LUA_TTHREAD:
sethvalue(L, gt(thvalue(o)), hvalue(L->top - 1));
break;
default:
res = 0;
break;
}
luaC_objbarrier(L, gcvalue(o), hvalue(L->top - 1));
L->top--;
lua_unlock(L);
return res;
}
/*
** `load' and `call' functions (run Lua code)
*/
#define adjustresults(L,nres) \
{ if (nres == LUA_MULTRET && L->top >= L->ci->top) L->ci->top = L->top; }
#define checkresults(L,na,nr) \
api_check(L, (nr) == LUA_MULTRET || (L->ci->top - L->top >= (nr) - (na)))
LUA_API void lua_call (lua_State *L, int nargs, int nresults) {
StkId func;
lua_lock(L);
api_checknelems(L, nargs+1);
checkresults(L, nargs, nresults);
func = L->top - (nargs+1);
luaD_call(L, func, nresults);
adjustresults(L, nresults);
lua_unlock(L);
}
/*
** Execute a protected call.
*/
struct CallS { /* data to `f_call' */
StkId func;
int nresults;
};
static void f_call (lua_State *L, void *ud) {
struct CallS *c = cast(struct CallS *, ud);
luaD_call(L, c->func, c->nresults);
}
LUA_API int lua_pcall (lua_State *L, int nargs, int nresults, int errfunc) {
struct CallS c;
int status;
ptrdiff_t func;
lua_lock(L);
api_checknelems(L, nargs+1);
checkresults(L, nargs, nresults);
if (errfunc == 0)
func = 0;
else {
StkId o = index2adr(L, errfunc);
api_checkvalidindex(L, o);
func = savestack(L, o);
}
c.func = L->top - (nargs+1); /* function to be called */
c.nresults = nresults;
status = luaD_pcall(L, f_call, &c, savestack(L, c.func), func);
adjustresults(L, nresults);
lua_unlock(L);
return status;
}
/*
** Execute a protected C call.
*/
struct CCallS { /* data to `f_Ccall' */
lua_CFunction func;
void *ud;
};
static void f_Ccall (lua_State *L, void *ud) {
struct CCallS *c = cast(struct CCallS *, ud);
Closure *cl;
cl = luaF_newCclosure(L, 0, getcurrenv(L));
cl->c.f = c->func;
setclvalue(L, L->top, cl); /* push function */
api_incr_top(L);
setpvalue(L->top, c->ud); /* push only argument */
api_incr_top(L);
luaD_call(L, L->top - 2, 0);
}
LUA_API int lua_cpcall (lua_State *L, lua_CFunction func, void *ud) {
struct CCallS c;
int status;
lua_lock(L);
c.func = func;
c.ud = ud;
status = luaD_pcall(L, f_Ccall, &c, savestack(L, L->top), 0);
lua_unlock(L);
return status;
}
LUA_API int lua_load (lua_State *L, lua_Reader reader, void *data,
const char *chunkname) {
ZIO z;
int status;
lua_lock(L);
if (!chunkname) chunkname = "?";
luaZ_init(L, &z, reader, data);
status = luaD_protectedparser(L, &z, chunkname);
lua_unlock(L);
return status;
}
LUA_API int lua_dump (lua_State *L, lua_Writer writer, void *data) {
int status;
TValue *o;
lua_lock(L);
api_checknelems(L, 1);
o = L->top - 1;
if (isLfunction(o))
status = luaU_dump(L, clvalue(o)->l.p, writer, data, 0);
else
status = 1;
lua_unlock(L);
return status;
}
LUA_API int lua_status (lua_State *L) {
return L->status;
}
/*
** Garbage-collection function
*/
LUA_API int lua_gc (lua_State *L, int what, int data) {
int res = 0;
global_State *g;
lua_lock(L);
g = G(L);
switch (what) {
case LUA_GCSTOP: {
g->GCthreshold = MAX_LUMEM;
break;
}
case LUA_GCRESTART: {
g->GCthreshold = g->totalbytes;
break;
}
case LUA_GCCOLLECT: {
luaC_fullgc(L);
break;
}
case LUA_GCCOUNT: {
/* GC values are expressed in Kbytes: #bytes/2^10 */
res = cast_int(g->totalbytes >> 10);
break;
}
case LUA_GCCOUNTB: {
res = cast_int(g->totalbytes & 0x3ff);
break;
}
case LUA_GCSTEP: {
lu_mem a = (cast(lu_mem, data) << 10);
if (a <= g->totalbytes)
g->GCthreshold = g->totalbytes - a;
else
g->GCthreshold = 0;
while (g->GCthreshold <= g->totalbytes)
luaC_step(L);
if (g->gcstate == GCSpause) /* end of cycle? */
res = 1; /* signal it */
break;
}
case LUA_GCSETPAUSE: {
res = g->gcpause;
g->gcpause = data;
break;
}
case LUA_GCSETSTEPMUL: {
res = g->gcstepmul;
g->gcstepmul = data;
break;
}
default: res = -1; /* invalid option */
}
lua_unlock(L);
return res;
}
/*
** miscellaneous functions
*/
LUA_API int lua_error (lua_State *L) {
lua_lock(L);
api_checknelems(L, 1);
luaG_errormsg(L);
lua_unlock(L);
return 0; /* to avoid warnings */
}
LUA_API int lua_next (lua_State *L, int idx) {
StkId t;
int more;
lua_lock(L);
t = index2adr(L, idx);
api_check(L, ttistable(t));
more = luaH_next(L, hvalue(t), L->top - 1);
if (more) {
api_incr_top(L);
}
else /* no more elements */
L->top -= 1; /* remove key */
lua_unlock(L);
return more;
}
LUA_API void lua_concat (lua_State *L, int n) {
lua_lock(L);
api_checknelems(L, n);
if (n >= 2) {
luaC_checkGC(L);
luaV_concat(L, n, cast_int(L->top - L->base) - 1);
L->top -= (n-1);
}
else if (n == 0) { /* push empty string */
setsvalue2s(L, L->top, luaS_newlstr(L, "", 0));
api_incr_top(L);
}
/* else n == 1; nothing to do */
lua_unlock(L);
}
LUA_API lua_Alloc lua_getallocf (lua_State *L, void **ud) {
lua_Alloc f;
lua_lock(L);
if (ud) *ud = G(L)->ud;
f = G(L)->frealloc;
lua_unlock(L);
return f;
}
LUA_API void lua_setallocf (lua_State *L, lua_Alloc f, void *ud) {
lua_lock(L);
G(L)->ud = ud;
G(L)->frealloc = f;
lua_unlock(L);
}
LUA_API void *lua_newuserdata (lua_State *L, size_t size) {
Udata *u;
lua_lock(L);
luaC_checkGC(L);
u = luaS_newudata(L, size, getcurrenv(L));
setuvalue(L, L->top, u);
api_incr_top(L);
lua_unlock(L);
return u + 1;
}
static const char *aux_upvalue (StkId fi, int n, TValue **val) {
Closure *f;
if (!ttisfunction(fi)) return NULL;
f = clvalue(fi);
if (f->c.isC) {
if (!(1 <= n && n <= f->c.nupvalues)) return NULL;
*val = &f->c.upvalue[n-1];
return "";
}
else {
Proto *p = f->l.p;
if (!(1 <= n && n <= p->sizeupvalues)) return NULL;
*val = f->l.upvals[n-1]->v;
return getstr(p->upvalues[n-1]);
}
}
LUA_API const char *lua_getupvalue (lua_State *L, int funcindex, int n) {
const char *name;
TValue *val;
lua_lock(L);
name = aux_upvalue(index2adr(L, funcindex), n, &val);
if (name) {
setobj2s(L, L->top, val);
api_incr_top(L);
}
lua_unlock(L);
return name;
}
LUA_API const char *lua_setupvalue (lua_State *L, int funcindex, int n) {
const char *name;
TValue *val;
StkId fi;
lua_lock(L);
fi = index2adr(L, funcindex);
api_checknelems(L, 1);
name = aux_upvalue(fi, n, &val);
if (name) {
L->top--;
setobj(L, val, L->top);
luaC_barrier(L, clvalue(fi), L->top);
}
lua_unlock(L);
return name;
}