server/liblua/src/lapi.c

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2022-03-05 12:44:06 +02:00
/*
** $Id: lapi.c,v 1.235a 2003/04/07 14:36:08 roberto Exp $
** Lua API
** See Copyright Notice in lua.h
*/
#include <assert.h>
#include <string.h>
#define lapi_c
#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_VERSION " " LUA_COPYRIGHT " $\n"
"$Authors: " LUA_AUTHORS " $\n"
"$URL: www.lua.org $\n";
#ifndef api_check
#define api_check(L, o) /*{ assert(o); }*/
#endif
#define api_checknelems(L, n) api_check(L, (n) <= (L->top - L->base))
#define api_incr_top(L) {api_check(L, L->top < L->ci->top); L->top++;}
static TObject *negindex (lua_State *L, int idx) {
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_GLOBALSINDEX: return gt(L);
default: {
TObject *func = (L->base - 1);
idx = LUA_GLOBALSINDEX - idx;
lua_assert(iscfunction(func));
return (idx <= clvalue(func)->c.nupvalues)
? &clvalue(func)->c.upvalue[idx-1]
: NULL;
}
}
}
static TObject *luaA_index (lua_State *L, int idx) {
if (idx > 0) {
api_check(L, idx <= L->top - L->base);
return L->base + idx - 1;
}
else {
TObject *o = negindex(L, idx);
api_check(L, o != NULL);
return o;
}
}
static TObject *luaA_indexAcceptable (lua_State *L, int idx) {
if (idx > 0) {
TObject *o = L->base+(idx-1);
api_check(L, idx <= L->stack_last - L->base);
if (o >= L->top) return NULL;
else return o;
}
else
return negindex(L, idx);
}
void luaA_pushobject (lua_State *L, const TObject *o) {
setobj2s(L->top, o);
incr_top(L);
}
LUA_API int lua_checkstack (lua_State *L, int size) {
int res;
lua_lock(L);
if ((L->top - L->base + size) > LUA_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;
lua_lock(to);
api_checknelems(from, n);
from->top -= n;
for (i = 0; i < n; i++) {
setobj2s(to->top, from->top + i);
api_incr_top(to);
}
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->top, L1);
api_incr_top(L);
lua_unlock(L);
lua_userstateopen(L1);
return L1;
}
/*
** basic stack manipulation
*/
LUA_API int lua_gettop (lua_State *L) {
return (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 = luaA_index(L, idx);
while (++p < L->top) setobjs2s(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 = luaA_index(L, idx);
for (q = L->top; q>p; q--) setobjs2s(q, q-1);
setobjs2s(p, L->top);
lua_unlock(L);
}
LUA_API void lua_replace (lua_State *L, int idx) {
lua_lock(L);
api_checknelems(L, 1);
setobj(luaA_index(L, idx), L->top - 1); /* write barrier */
L->top--;
lua_unlock(L);
}
LUA_API void lua_pushvalue (lua_State *L, int idx) {
lua_lock(L);
setobj2s(L->top, luaA_index(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 = luaA_indexAcceptable(L, idx);
return (o == NULL) ? 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 = luaA_indexAcceptable(L, idx);
return (o == NULL) ? 0 : iscfunction(o);
}
LUA_API int lua_isnumber (lua_State *L, int idx) {
TObject n;
const TObject *o = luaA_indexAcceptable(L, idx);
return (o != NULL && 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 TObject *o = luaA_indexAcceptable(L, idx);
return (o != NULL && (ttisuserdata(o) || ttislightuserdata(o)));
}
LUA_API int lua_rawequal (lua_State *L, int index1, int index2) {
StkId o1 = luaA_indexAcceptable(L, index1);
StkId o2 = luaA_indexAcceptable(L, index2);
return (o1 == NULL || o2 == NULL) ? 0 /* index out of range */
: 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 = luaA_indexAcceptable(L, index1);
o2 = luaA_indexAcceptable(L, index2);
i = (o1 == NULL || o2 == NULL) ? 0 /* index out of range */
: 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 = luaA_indexAcceptable(L, index1);
o2 = luaA_indexAcceptable(L, index2);
i = (o1 == NULL || o2 == NULL) ? 0 /* index out-of-range */
: luaV_lessthan(L, o1, o2);
lua_unlock(L);
return i;
}
LUA_API lua_Number lua_tonumber (lua_State *L, int idx) {
TObject n;
const TObject *o = luaA_indexAcceptable(L, idx);
if (o != NULL && tonumber(o, &n))
return nvalue(o);
else
return 0;
}
LUA_API int lua_toboolean (lua_State *L, int idx) {
const TObject *o = luaA_indexAcceptable(L, idx);
return (o != NULL) && !l_isfalse(o);
}
LUA_API const char *lua_tostring (lua_State *L, int idx) {
StkId o = luaA_indexAcceptable(L, idx);
if (o == NULL)
return NULL;
else if (ttisstring(o))
return svalue(o);
else {
const char *s;
lua_lock(L); /* `luaV_tostring' may create a new string */
s = (luaV_tostring(L, o) ? svalue(o) : NULL);
luaC_checkGC(L);
lua_unlock(L);
return s;
}
}
LUA_API size_t lua_strlen (lua_State *L, int idx) {
StkId o = luaA_indexAcceptable(L, idx);
if (o == NULL)
return 0;
else if (ttisstring(o))
return tsvalue(o)->tsv.len;
else {
size_t l;
lua_lock(L); /* `luaV_tostring' may create a new string */
l = (luaV_tostring(L, o) ? tsvalue(o)->tsv.len : 0);
lua_unlock(L);
return l;
}
}
LUA_API lua_CFunction lua_tocfunction (lua_State *L, int idx) {
StkId o = luaA_indexAcceptable(L, idx);
return (o == NULL || !iscfunction(o)) ? NULL : clvalue(o)->c.f;
}
LUA_API void *lua_touserdata (lua_State *L, int idx) {
StkId o = luaA_indexAcceptable(L, idx);
if (o == NULL) return NULL;
switch (ttype(o)) {
case LUA_TUSERDATA: return (uvalue(o) + 1);
case LUA_TLIGHTUSERDATA: return pvalue(o);
default: return NULL;
}
}
LUA_API lua_State *lua_tothread (lua_State *L, int idx) {
StkId o = luaA_indexAcceptable(L, idx);
return (o == NULL || !ttisthread(o)) ? NULL : thvalue(o);
}
LUA_API const void *lua_topointer (lua_State *L, int idx) {
StkId o = luaA_indexAcceptable(L, idx);
if (o == NULL) return NULL;
else {
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_pushlstring (lua_State *L, const char *s, size_t len) {
lua_lock(L);
luaC_checkGC(L);
setsvalue2s(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);
cl->c.f = fn;
L->top -= n;
while (n--)
setobj2n(&cl->c.upvalue[n], L->top+n);
setclvalue(L->top, 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);
}
/*
** get functions (Lua -> stack)
*/
LUA_API void lua_gettable (lua_State *L, int idx) {
StkId t;
lua_lock(L);
t = luaA_index(L, idx);
setobj2s(L->top - 1, luaV_gettable(L, t, L->top - 1, 0));
lua_unlock(L);
}
LUA_API void lua_rawget (lua_State *L, int idx) {
StkId t;
lua_lock(L);
t = luaA_index(L, idx);
api_check(L, ttistable(t));
setobj2s(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 = luaA_index(L, idx);
api_check(L, ttistable(o));
setobj2s(L->top, luaH_getnum(hvalue(o), n));
api_incr_top(L);
lua_unlock(L);
}
LUA_API void lua_newtable (lua_State *L) {
lua_lock(L);
luaC_checkGC(L);
sethvalue(L->top, luaH_new(L, 0, 0));
api_incr_top(L);
lua_unlock(L);
}
LUA_API int lua_getmetatable (lua_State *L, int objindex) {
const TObject *obj;
Table *mt = NULL;
int res;
lua_lock(L);
obj = luaA_indexAcceptable(L, objindex);
if (obj != NULL) {
switch (ttype(obj)) {
case LUA_TTABLE:
mt = hvalue(obj)->metatable;
break;
case LUA_TUSERDATA:
mt = uvalue(obj)->uv.metatable;
break;
}
}
if (mt == NULL || mt == hvalue(defaultmeta(L)))
res = 0;
else {
sethvalue(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 = luaA_index(L, idx);
setobj2s(L->top, isLfunction(o) ? &clvalue(o)->l.g : gt(L));
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 = luaA_index(L, idx);
luaV_settable(L, t, L->top - 2, L->top - 1);
L->top -= 2; /* pop index and value */
lua_unlock(L);
}
LUA_API void lua_rawset (lua_State *L, int idx) {
StkId t;
lua_lock(L);
api_checknelems(L, 2);
t = luaA_index(L, idx);
api_check(L, ttistable(t));
setobj2t(luaH_set(L, hvalue(t), L->top-2), L->top-1); /* write barrier */
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 = luaA_index(L, idx);
api_check(L, ttistable(o));
setobj2t(luaH_setnum(L, hvalue(o), n), L->top-1); /* write barrier */
L->top--;
lua_unlock(L);
}
LUA_API int lua_setmetatable (lua_State *L, int objindex) {
TObject *obj, *mt;
int res = 1;
lua_lock(L);
api_checknelems(L, 1);
obj = luaA_index(L, objindex);
mt = (!ttisnil(L->top - 1)) ? L->top - 1 : defaultmeta(L);
api_check(L, ttistable(mt));
switch (ttype(obj)) {
case LUA_TTABLE: {
hvalue(obj)->metatable = hvalue(mt); /* write barrier */
break;
}
case LUA_TUSERDATA: {
uvalue(obj)->uv.metatable = hvalue(mt); /* write barrier */
break;
}
default: {
res = 0; /* cannot set */
break;
}
}
L->top--;
lua_unlock(L);
return res;
}
LUA_API int lua_setfenv (lua_State *L, int idx) {
StkId o;
int res = 0;
lua_lock(L);
api_checknelems(L, 1);
o = luaA_index(L, idx);
L->top--;
api_check(L, ttistable(L->top));
if (isLfunction(o)) {
res = 1;
clvalue(o)->l.g = *(L->top);
}
lua_unlock(L);
return res;
}
/*
** `load' and `call' functions (run Lua code)
*/
LUA_API void lua_call (lua_State *L, int nargs, int nresults) {
StkId func;
lua_lock(L);
api_checknelems(L, nargs+1);
func = L->top - (nargs+1);
luaD_call(L, func, 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);
func = (errfunc == 0) ? 0 : savestack(L, luaA_index(L, errfunc));
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);
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);
cl->c.f = c->func;
setclvalue(L->top, cl); /* push function */
incr_top(L);
setpvalue(L->top, c->ud); /* push only argument */
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_Chunkreader reader, void *data,
const char *chunkname) {
ZIO z;
int status;
int c;
lua_lock(L);
if (!chunkname) chunkname = "?";
luaZ_init(&z, reader, data, chunkname);
c = luaZ_lookahead(&z);
status = luaD_protectedparser(L, &z, (c == LUA_SIGNATURE[0]));
lua_unlock(L);
return status;
}
LUA_API int lua_dump (lua_State *L, lua_Chunkwriter writer, void *data) {
int status;
TObject *o;
lua_lock(L);
api_checknelems(L, 1);
o = L->top - 1;
if (isLfunction(o) && clvalue(o)->l.nupvalues == 0) {
luaU_dump(L, clvalue(o)->l.p, writer, data);
status = 1;
}
else
status = 0;
lua_unlock(L);
return status;
}
/*
** Garbage-collection functions
*/
/* GC values are expressed in Kbytes: #bytes/2^10 */
#define GCscalel(x) ((x)>>10)
#define GCscale(x) (cast(int, GCscalel(x)))
#define GCunscale(x) (cast(lu_mem, x)<<10)
LUA_API int lua_getgcthreshold (lua_State *L) {
int threshold;
lua_lock(L);
threshold = GCscale(G(L)->GCthreshold);
lua_unlock(L);
return threshold;
}
LUA_API int lua_getgccount (lua_State *L) {
int count;
lua_lock(L);
count = GCscale(G(L)->nblocks);
lua_unlock(L);
return count;
}
LUA_API void lua_setgcthreshold (lua_State *L, int newthreshold) {
lua_lock(L);
if (cast(lu_mem, newthreshold) > GCscalel(MAX_LUMEM))
G(L)->GCthreshold = MAX_LUMEM;
else
G(L)->GCthreshold = GCunscale(newthreshold);
luaC_checkGC(L);
lua_unlock(L);
}
/*
** miscellaneous functions
*/
LUA_API const char *lua_version (void) {
return LUA_VERSION;
}
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 = luaA_index(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);
luaC_checkGC(L);
api_checknelems(L, n);
if (n >= 2) {
luaV_concat(L, n, L->top - L->base - 1);
L->top -= (n-1);
}
else if (n == 0) { /* push empty string */
setsvalue2s(L->top, luaS_newlstr(L, NULL, 0));
api_incr_top(L);
}
/* else n == 1; nothing to do */
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);
setuvalue(L->top, u);
api_incr_top(L);
lua_unlock(L);
return u + 1;
}
LUA_API int lua_pushupvalues (lua_State *L) {
Closure *func;
int n, i;
lua_lock(L);
api_check(L, iscfunction(L->base - 1));
func = clvalue(L->base - 1);
n = func->c.nupvalues;
luaD_checkstack(L, n + LUA_MINSTACK);
for (i=0; i<n; i++) {
setobj2s(L->top, &func->c.upvalue[i]);
L->top++;
}
lua_unlock(L);
return n;
}
static const char *aux_upvalue (lua_State *L, int funcindex, int n,
TObject **val) {
Closure *f;
StkId fi = luaA_index(L, funcindex);
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;
TObject *val;
lua_lock(L);
name = aux_upvalue(L, funcindex, n, &val);
if (name) {
setobj2s(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;
TObject *val;
lua_lock(L);
api_checknelems(L, 1);
name = aux_upvalue(L, funcindex, n, &val);
if (name) {
L->top--;
setobj(val, L->top); /* write barrier */
}
lua_unlock(L);
return name;
}